EPA
             Integrated Science Assessment for
             Paniculate Matter
                               '

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&EPA
United States                              December 2009
       Pr0tectl°nEPA/600/R-08/139F
  Integrated Science Assessment for
              Particulate  Matter
         National Center for Environmental Assessment-RTF Division
                Office of Research and Development
                U.S. Environmental Protection Agency
                  Research Triangle Park, NC

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                             Disclaimer
     This document has been reviewed in accordance with U.S. Environmental Protection Agency
policy and approved for publication. Mention of trade names or commercial products does not
constitute endorsement or recommendation for use.
December 2009

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                    Table of Contents
PM ISA PROJECT TEAM	XLII
AUTHORS, CONTRIBUTORS, REVIEWERS	XLV
CLEAN AIR SCIENTIFIC ADVISORY COMMITTEE FOR PARTICULATE MATTER NAAQS	LI
ACRONYMS AND ABBREVIATIONS	LIN
CHAPTER 1. INTRODUCTION	1-2
       1.1.  Legislative Requirements	1-4
1 .2. History of Reviews of the NAAQS for PM
1.3. ISA Development
1.4. Document Organization
1.5. EPA Framework for Causal Determination
1.5.1. Scientific Evidence Used in Establishing Causality
1.5.2. Association and Causation
1 .5.3. Evaluating Evidence for Inferring Causation
1 .5.4. Application of Framework for Causal Determination
1 .5.5. First Step— Determination of Causality
1 .5.6. Second Step— Evaluation of Response
1.5.6.1. Effects on Human Populations
1.5.6.2. Effects on Public Welfare
1 .5.7. Concepts in Evaluating Adversity of Health Effects
1.6. Summary
Chapter 1 References
1-5
1-9
1-13
1-14
1-15
1-15
1-15
1-19
1-20
1-22
1-22
1-24
1-24
1-24
1-26
CHAPTER 2. INTEGRATIVE HEALTH AND WELFARE EFFECTS OVERVIEW	2-28
2.1.
2.2.
2.3.
Concentrations and Sources of Atmospheric PM
2.1.1. Ambient PM Variability and Correlations
2. 1 . 1 . 1 . Spatial Variability across the U.S.
2. 1 . 1 .2. Spatial Variability on the Urban and Neighborhood Scales
2.1.2. Trends and Temporal Variability
2.1.3. Correlations between Copollutants
2.1.4. Measurement Techniques
2.1.5. PM Formation in the Atmosphere and Removal
2.1.6. Source Contributions to PM
2.1.7. Policy-Relevant Background
Human Exposure
2.2.1 . Spatial Scales of PM Exposure Assessment
2.2.2. Exposure to PM Components and Copollutants
2.2.3. Implications for Epidemiologic Studies
Health Effects
2.3.1. Exposure to PM9S
2.3.1.1. Effects of Short-Term Exposure to PM9S
2.3.1.2. Effects of Long-Term Exposure to PM2s
2-29
2-29
2-29
2-30
2-30
2-31
2-31
2-31
2-32
2-33
2-33
2-33
2-34
2-34
2-35
2-36
2-36
2-38
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              2.3.2.  Integration of PM25 Health Effects	2-40
              2.3.3.  Exposure to PM10.25	2-45
                     2.3.3.1.  Effects of Short-Term Exposure to PM10.25	2-45
              2.3.4.  Integration of PM10.25 Effects	2-46
              2.3.5.  Exposure to UFPs	2-48
                     2.3.5.1.  Effects of Short-Term Exposure to UFPs	2-48
              2.3.6.  Integration of UFP Effects	2-49

          2.4. Policy Relevant Considerations	2-50
              2.4.1.  Potentially Susceptible Populations	2-50
              2.4.2.  Lag Structure of PM-Morbidity and PM-Mortality Associations	2-51
                     2.4.2.1.  PM-Cardiovascular Morbidity Associations	2-51
                     2.4.2.2.  PM-Respiratory Morbidity Associations	2-51
                     2.4.2.3.  PM-Mortality Associations	2-52
              2.4.3.  PM Concentration-Response  Relationship	2-52
              2.4.4.  PM Sources and Constituents Linked to Health Effects	2-53

          2.5. Welfare Effects	2-54
              2.5.1.  Summary of Effects on Visibility	2-54
              2.5.2.  Summary of Effects on Climate	2-55
              2.5.3.  Summary of Ecological Effects of PM	2-56
              2.5.4.  Summary of Effects on Materials	2-57

          2.6. Summary of Health Effects and Welfare Effects Causal Determinations	2-58

          Chapter 2 References	2-61

CHAPTERS. SOURCE TO HUMAN EXPOSURE	3-1

          3.1. Introduction	3-1

          3.2. Overview of Basic Aerosol Properties	3-1

          3.3. Sources, Emissions and Deposition of Primary and Secondary PM	3-6
              3.3.1.  Emissions of Primary PM and Precursors to Secondary PM	3-8
              3.3.2.  Formation of Secondary PM	3-10
                     3.3.2.1.  Formation of Nitrate and Sulfate	3-10
                     3.3.2.2.  Formation of Secondary Organic Aerosol	3-10
                     3.3.2.3.  Formation of New Particles	3-12
              3.3.3.  Mobile Source Emissions	3-13
                     3.3.3.1.  Emissions from Gasoline Fueled Engines	3-13
                     3.3.3.2.  Emissions from Diesel Fueled Engines	3-13
              3.3.4.  Deposition of PM	3-14
                     3.3.4.1.  Deposition Forms	3-16
                     3.3.4.2.  Methods for Estimating Dry  Deposition	3-17
                     3.3.4.3.  Factors Affecting Dry Deposition Rates and Totals	3-18

          3.4. Monitoring of PM	3-20
              3.4.1.  Ambient Measurement Techniques	3-20
                     3.4.1.1.  PMMass	3-20
                     3.4.1.2.  PMSpeciation	3-23
                     3.4.1.3.  Multiple-Component Measurements on Individual Particles	3-28
                     3.4.1.4.  UFPs:  Mass, Surface Area,  and Number	3-29
                     3.4.1.5.  PM Size  Distribution	3-29
                     3.4.1.6.  Satellite Measurement	3-29
              3.4.2.  Ambient Network Design	3-30
                     3.4.2.1.  Monitor Siting Requirements	3-30
                     3.4.2.2.  Spatial and Temporal Coverage	3-31
                     3.4.2.3.  Network Application for Exposure Assessment with Respect to
                             Susceptible Populations	3-36

          3.5. Ambient PM Concentrations                                                          3-40
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               3.5.1.  Spatial Distribution	3-41
                     3.5.1.1. Variability across the U.S.	3-42
                     3.5.1.2. Urban-Scale Variability	3-60
                     3.5.1.3. Neighborhood-Scale Variability	3-85
               3.5.2.  Temporal Variability	3-91
                     3.5.2.1. Regional Trends	3-91
                     3.5.2.2. Seasonal Variations	3-96
                     3.5.2.3. Hourly Variability	3-97
               3.5.3.  Statistical Associations with Copollutants	3-100

          3.6. Mathematical Modeling of PM	3-104
               3.6.1.  Estimating Source Contributions to PM Using Receptor Models	3-104
                     3.6.1.1. Receptor Models	3-104
               3.6.2.  Chemistry Transport Models	3-109
                     3.6.2.1. Global Scale	3-111
                     3.6.2.2. Regional Scale	3-111
                     3.6.2.3. Local or Neighborhood Scale	3-113
               3.6.3.  Air Quality Model Evaluation for Air Concentrations	3-113
                     3.6.3.1. Ground-based Comparisons of Photochemical Dynamics	3-120
                     3.6.3.2. Predicted Chemistry for Nitrates and Related Compounds	3-120
               3.6.4.  Evaluating Concentrations and Deposition of PM Components with CTMs	3-126
                     3.6.4.1. Global CTM Performance	3-126
                     3.6.4.2. Regional CTM Performance	3-127

          3.7. Background PM	3-139
               3.7.1.  Contributors to PRB Concentrations of PM	3-139
                     3.7.1.1. Estimates of PRB Concentrations in Previous Assessments	3-140
                     3.7.1.2. Chemistry Transport Models for Predicting PRB Concentrations	3-142

          3.8. Issues in Exposure Assessment for PM and its Components	3-152
               3.8.1.  General Exposure Concepts	3-153
               3.8.2.  Personal and Microenvironmental Exposure Monitoring	3-155
                     3.8.2.1. New Developments in Personal Exposure Monitoring Instrumentation	3-155
                     3.8.2.2. New Developments in Microenvironmental Exposure Monitoring
                             Instrumentation	3-156
               3.8.3.  Exposure Modeling	3-157
                     3.8.3.1. Time-Weighted Microenvironmental Models	3-157
                     3.8.3.2. Stochastic Population Exposure Models	3-158
                     3.8.3.3. Dispersion Models	3-160
                     3.8.3.4. Land Use Regression and GIS-Based Models	3-160
               3.8.4.  Exposure Assessment  Studies	3-162
                     3.8.4.1. Micro-to-Neighborhood Scale Ambient PM Exposure	3-162
                     3.8.4.2. Ambient PM Exposure Estimates from Central Site Monitoring Data	3-165
                     3.8.4.3. Infiltration	3-168
               3.8.5.  Multicomponent and Multipollutant PM Exposures	3-170
                     3.8.5.1. Exposure Issues Related to PM Composition	3-170
                     3.8.5.2. Exposure to PM  and  Copollutants	3-175
               3.8.6.  Implications  of Exposure Assessment  Issues for Interpretation of Epidemiologic
                     Studies	3-176
                     3.8.6.1. Measurement Error	3-176
                     3.8.6.2. Model-Related Errors	3-177
                     3.8.6.3. Spatial Variability	3-179
                     3.8.6.4. Temporal Variability	3-181
                     3.8.6.5. Use of Surrogates for PM Exposure	3-183
                     3.8.6.6. Compositional Differences	3-184
                     3.8.6.7. Conclusions	3-184

          3.9. Summary and Conclusions	3-185
               3.9.1.  Concentrations and Sources of Atmospheric PM	3-185
                     3.9.1.1. PM Source Characteristics	3-185
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3.9.1.2. Measurement Techniques
3.9.1.3. Ambient PM Variability and Correlations
3.9.1.4. Temporal Variability
3.9.1.5. Correlations between Copollutants
3.9.1.6. Source Contributions to PM
3.9.1.7. Policy-Relevant Background
3.9.2. Human Exposure
3.9.2.1. Characterizing Human Exposure
3.9.2.2. Spatial Scales of PM Exposure Assessment
3.9.2.3. Multicomponent and Multipollutant PM Exposures
3.9.2.4. Implications for Epidemiologic Studies
Chapter 3 References
CHAPTER 4. DOSIMETRY
4.1. Introduction
4.1.1. Size Characterization of Inhaled Particles
4.1.2. Structure of the Respiratory Tract
4.2. Particle Deposition
4.2.1. Mechanisms of Deposition
4.2.2. Deposition Patterns
4.2.2. 1 . Total Respiratory Tract Deposition
4.2.2.2. Extrathoracic Region
4.2.2.3. Tracheobronchial and Alveolar Region
4.2.2.4. Localized Deposition Sites
4.2.3. Interspecies Patterns of Deposition
4.2.4. Biological Factors Modulating Deposition
4.2.4.1. Physical Activity
4.2.4.2. Age
4.2.4.3. Gender
4.2.4.4. Anatomical Variability
4.2.4.5. Respiratory Tract Disease
4.2.4.6. Hygroscopicity of Aerosols
4.2.5. Summary
4.3. Clearance of Poorly Soluble Particles
4.3.1 . Clearance Mechanisms and Kinetics
4.3.1.1. Extrathoracic Region
4.3.1.2. Tracheobronchial Region
4.3.1.3. Alveolar Region
4.3.2. Interspecies Patterns of Clearance and Retention
4.3.3. Particle Translocation
4.3.3.1. Alveolar Region
4.3.3.2. Olfactory Region
4.3.4. Factors Modulating Clearance
4.3.4.1. Age
4.3.4.2. Gender
4.3.4.3. Respiratory Tract Disease
4.3.4.4. Particle Overload
4.3.5. Summary
4.4. Clearance of Soluble Materials
4.4.1 . Clearance Mechanisms and Kinetics
4.4.2. Factors Modulating Clearance
4.4.2.1. Age
4.4.2.2. Physical Activity
4.4.2.3. Disease
4.4.2.4. Concurrent Exposures
3-185
3-186
3-187
3-188
3-188
3-189
3-189
3-189
3-190
3-191
3-191
3-193
4-1
4-1
4-2
4-3
4-5
4-6
4-7
4-8
4-9
4-10
4-10
4-11
4-11
4-12
4-13
4-14
4-14
4-15
4-16
4-16
4-17
4-17
4-17
4-18
4-19
4-19
4-20
4-21
4-22
4-23
4-23
4-24
4-24
4-25
4-25
4-26
4-26
4-27
4-28
4-28
4-28
4-29
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              4.4.3.  Summary	4-29

          Chapter 4 References	4-30

CHAPTER 5. POSSIBLE PATHWAYS/ MODES OF ACTION	5-1

          5.1. Pulmonary Effects	5-1
              5.1.1.  Reactive Oxygen Species	5-1
              5.1.2.  Activation of Cell Signaling Pathways	5-3
              5.1.3.  Pulmonary Inflammation	5-4
              5.1.4.  Respiratory Tract Barrier Function	5-6
              5.1.5.  Antioxidant Defenses and Adaptive Responses	5-6
              5.1.6.  Pulmonary Function	5-7
              5.1.7.  Allergic Disorders	5-8
              5.1.8.  Impaired Lung Defense Mechanisms	5-8
              5.1.9.  Resolution of Inflammation/Progression or Exacerbation of Disease	5-8
                     5.1.9.1.  Factors Affecting the Retention of PM	5-9
                     5.1.9.2.  Factors Affecting the Balance of Pro/Anti-lnflammatory Mediators,
                             Oxidants/Anti-Oxidants and Proteases/Anti-Proteases	5-9
                     5.1.9.3.  Pre-Existing Disease	5-10
              5.1.10. Pulmonary DMA Damage	5-10
              5.1.11. Epigenetic Changes	5-10
              5.1.12. Lung Development	5-11

          5.2. Systemic Inflammation	5-12
              5.2.1.  Endothelial Dysfunction and Altered Vasoreactivity	5-13
              5.2.2.  Activation of Coagulation and Acute Phase Response	5-14
              5.2.3.  Atherosclerosis	5-15

          5.3. Activation of the Autonomic Nervous System by Pulmonary Reflexes	5-16

          5.4. Translocation of UFPs or Soluble PM Components	5-17

          5.5. Disease of the Cardiovascular and Other Organ Systems	5-18

          5.6. Acute and Chronic Responses	5-19

          5.7. Results of New Inhalation Studies which Contribute to Modes of Action	5-19

          5.8. Gaps in Knowledge	5-22

          Chapter 5 References	5-23

CHAPTERS. INTEGRATED HEALTH EFFECTS OF SHORT-TERM PM EXPOSURE	6-1

          6.1. Introduction	6-1

          6.2. Cardiovascular and Systemic Effects	6-2
              6.2.1.  Heart Rate and Heart Rate Variability	6-2
                     6.2.1.1.  Epidemiologic Studies	6-2
                     6.2.1.2.  Controlled Human Exposure Studies	6-8
                     6.2.1.3.  lexicological Studies	6-10
              6.2.2.  Arrhythmia	6-13
                     6.2.2.1.  Epidemiologic Studies	6-13
                     6.2.2.2.  Toxicological Studies	6-18
              6.2.3.  Ischemia	6-20
                     6.2.3.1.  Epidemiologic Studies	6-20
                     6.2.3.2.  Controlled Human Exposure Studies	6-22
                     6.2.3.3.  Toxicological Studies	6-23
              6.2.4.  Vasomotor Function	6-24
                     6.2.4.1.  Epidemiologic Studies	6-24
                     6.2.4.2.  Controlled Human Exposure Studies	6-26
                     6.2.4.3.  Toxicological Studies	6-29
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               6.2.5.   Blood Pressure	6-33
                      6.2.5.1.  Epidemiologic Studies	6-33
                      6.2.5.2.  Controlled Human Exposure Studies	6-36
                      6.2.5.3.  Toxicological Studies	6-37
               6.2.6.   Cardiac Contractility	6-38
                      6.2.6.1.  Toxicological Studies	6-38
               6.2.7.   Systemic Inflammation	6-39
                      6.2.7.1.  Epidemiologic Studies	6-40
                      6.2.7.2.  Controlled Human Exposure Studies	6-44
                      6.2.7.3.  Toxicological Studies	6-46
               6.2.8.   Hemostasis, Thrombosis and Coagulation Factors	6-47
                      6.2.8.1.  Epidemiologic Studies	6-47
                      6.2.8.2.  Controlled Human Exposure Studies	6-48
                      6.2.8.3.  Toxicological Studies	6-50
               6.2.9.   Systemic and Cardiovascular Oxidative Stress	6-52
                      6.2.9.1.  Epidemiologic Studies	6-52
                      6.2.9.2.  Controlled Human Exposure Studies	6-53
                      6.2.9.3.  Toxicological Studies	6-54
               6.2.10. Hospital Admissions and Emergency Department Visits	6-56
                      6.2.10.1. All Cardiovascular Disease	6-60
                      6.2.10.2. Cardiac Diseases	6-64
                      6.2.10.3. Ischemic Heart Disease	6-64
                      6.2.10.4. Acute Myocardial Infarction	6-67
                      6.2.10.5. Congestive Heart Failure	6-68
                      6.2.10.6. Cardiac Arrhythmias	6-69
                      6.2.10.7. Cerebrovascular Disease	6-70
                      6.2.10.8. Peripheral Vascular Disease	6-72
                      6.2.10.9. Copollutant Models	6-72
                      6.2.10.10.   Concentration Response	6-75
                      6.2.10.11.   Out of Hospital Cardiac Arrest	6-76
               6.2.11. Cardiovascular Mortality	6-77
               6.2.12. Summary and Causal Determinations	6-78
                      6.2.12.1. PM25	6-78
                      6.2.12.2. PM10.25	6-81
                      6.2.12.3. UFPs	6-83

          6.3. Respiratory Effects	6-84
               6.3.1.   Respiratory Symptoms and Medication Use	6-84
                      6.3.1.1.  Epidemiologic Studies	6-84
                      6.3.1.2.  Controlled Human Exposure Studies	6-93
               6.3.2.   Pulmonary Function	6-94
                      6.3.2.1.  Epidemiologic Studies	6-95
                      6.3.2.2.  Controlled Human Exposure Studies	6-98
                      6.3.2.3.  Toxicological Studies	6-99
               6.3.3.   Pulmonary Inflammation	6-101
                      6.3.3.1.  Epidemiologic Studies	6-101
                      6.3.3.2.  Controlled Human Exposure Studies	6-104
                      6.3.3.3.  Toxicological Studies	6-106
               6.3.4.   Pulmonary Oxidative Responses	6-110
                      6.3.4.1.  Controlled Human Exposure Studies	6-111
                      6.3.4.2.  Toxicological Studies	6-112
               6.3.5.   Pulmonary Injury	6-114
                      6.3.5.1.  Epidemiologic Studies	6-114
                      6.3.5.2.  Controlled Human Exposure Studies	6-114
                      6.3.5.3.  Toxicological Studies	6-115
               6.3.6.   Allergic Responses	6-122
                      6.3.6.1.  Epidemiologic Studies	6-122
                      6.3.6.2.  Controlled Human Exposure Studies	6-122
                      6.3.6.3.  Toxicological Studies	6-123
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6.3.7. Host Defense
6.3.7.1. Epidemiologic Studies
6.3.7.2. Toxicological Studies
6.3.8. Respiratory ED Visits, Hospital Admissions and Physician Visits
6.3.8.1. All Respiratory Diseases
6.3.8.2. Asthma
6.3.8.3. Chronic Obstructive Pulmonary Disease
6.3.8.4. Pneumonia and Respiratory Infections
6.3.8.5. Copollutant Models
6.3.9. Respiratory Mortality
6.3.10. Summary and Causal Determinations
6.3.10.1. PM,,
6.3.10.2. PMm.9,
6.3.10.3. UFPs
6.4. Central Nervous System Effects
6.4.1. Epidemiologic Studies
6.4.2. Controlled Human Exposure Studies
6.4.3. Toxicological Studies
6.4.3.1. Urban Air
6.4.3.2. CAPs
6.4.3.3. Diesel Exhaust
6.4.3.4. Summary of Toxicological Study Findings of CMS Effects
6.4.4. Summary and Causal Determination
6.5. Mortality
6.5.1 . Summary of Findings from 2004 PM AQCD
6.5.2. Associations of Mortality and Short-Term Exposure to PM
6.5.2.1. PMin
6.5.2.2. PM,fi
6.5.2.3. Thoracic Coarse Particles (PMin-2s)
6.5.2.4. Ultrafine Particles
6.5.2.5. Chemical Components of PM
6.5.2.6. Source-Apportioned PM Analyses
6.5.2.7. Investigation of Concentration-Response Relationship
6.5.3. Summary and Causal Determinations
6.5.3.1. PM7,
6.5.3.2. PMin.?s
6.5.3.3. UFPs
6.6. Attribution of Ambient PM Health Effects to Specific Constituents or Sources
6.6.1. Evaluation Approach
6.6.2. Findings
6.6.2. 1 . Epidemiologic Studies
6.6.2.2. Controlled Human Exposure Studies
6.6.2.3. Toxicological Studies
6.6.3. Summary by Health Effects
6.6.4. Conclusion
Chapter 6 References
CHAPTER?. INTEGRATED HEALTH EFFECTS OF LONG-TERM PM EXPOSURE
7.1. Introduction
7.2. Cardiovascular and Systemic Effects
7.2.1. Atherosclerosis
7.2.1.1. Epidemiologic Studies
7.2.1.2. Toxicological Studies
7.2.2. Venous Thromboembolism
7.2.2. 1 . Epidemiologic Studies
6-129
6-129
6-129
6-132
6-133
6-137
6-142
6-143
6-147
6-149
6-149
6-149
6-152
6-153
6-154
6-154
6-155
6-155
6-155
6-156
6-156
6-157
6-157
6-158
6-158
6-159
6-160
6-174
6-184
6-190
6-191
6-196
6-197
6-200
6-200
6-201
6-202
6-202
6-202
6-203
6-203
6-206
6-206
6-210
6-211
6-213
7-1
7-1
7-1
7-2
7-2
7-4
7-6
7-7
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7.2.3. Metabolic Syndromes
7.2.3.1. Epidemiologic Studies
7.2.3.2. Toxicological Studies
7.2.4. Systemic Inflammation, Immune Function, and Blood Coagulation
7.2.4. 1 . Epidemiologic Studies
7.2.4.2. Toxicological Studies
7.2.5. Renal and Vascular Function
7.2.5.1. Epidemiologic Studies
7.2.5.2. Toxicological Studies
7.2.6. Autonomic Function
7.2.6.1. Toxicological Studies
7.2.7. Cardiac changes
7.2.7.1. Toxicological studies
7.2.8. Left Ventricular Mass and Function
7.2.9. Clinical Outcomes in Epidemiologic Studies
7.2.10. Cardiovascular Mortality
7.2.11. Summary and Causal Determinations
7.2.11. 1.PM,,
7.2.11.2. PMin.™
7.2.11.3. UFPs
7.3. Respiratory Effects
7.3.1 . Respiratory Symptoms and Disease Incidence
7.3.1.1. Epidemiologic Studies
7.3.2. Pulmonary Function
7.3.2.1. Epidemiologic Studies
7.3.2.2. Toxicological Studies
7.3.3. Pulmonary Inflammation
7.3.3.1. Epidemiologic Studies
7.3.3.2. Toxicological Studies
7.3.4. Pulmonary Oxidative Response
7.3.4.1. Toxicological Studies
7.3.5. Pulmonary Injury
7.3.5.1. Toxicological Studies
7.3.6. Allergic Responses
7.3.6.1. Epidemiologic Studies
7.3.6.2. Toxicological Studies
7.3.7. Host Defense
7.3.7.1. Epidemiologic Studies
7.3.7.2. Toxicological Studies
7.3.8. Respiratory Mortality
7.3.9. Summary and Causal Determinations
7.3.9.1. PM7,
7.3.9.2. PMin.?s
7.3.9.3. UFPs
7.4. Reproductive, Developmental, Prenatal and Neonatal Outcomes
7.4.1. Epidemiologic Studies
7.4.1.1. Low Birth Weight
7.4.1.2. Preterm Birth
7.4.1.3. Growth Restriction
7.4.1.4. Birth Defects
7.4.1.5. Infant Mortality
7.4.1.6. Decrements in Sperm Quality
7.4.2. Toxicological Studies
7.4.2.1. Female Reproductive Effects
7.4.2.2. Male Reproductive Effects
7.4.2.3. Multiple Generation Effects
7.4.2.4. Receptor Mediated Effects
7-7
7-7
7-7
7-8
7-8
7-8
7-9
7-10
7-11
7-12
7-12
7-12
7-12
7-13
7-13
7-17
7-18
7-18
7-19
7-19
7-20
7-20
7-20
7-26
7-26
7-30
7-32
7-32
7-32
7-34
7-34
7-35
7-35
7-38
7-38
7-39
7-40
7-40
7-40
7-41
7-42
7-42
7-43
7-44
7-44
7-44
7-45
7-48
7-51
7-52
7-53
7-58
7-58
7-59
7-60
7-62
7-63
December 2009

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7.4.2.5. Developmental Effects
7.4.3. Summary and Causal Determinations
7.4.3.1. PM,,
7.4.3.2. PMin.,,
7.4.3.3. UFPs
7.5. Cancer, Mutagenicity, and Genotoxicity
7.5.1. Epidemiologic Studies
7.5.1.1. Lung Cancer Mortality and Incidence
7.5.1.2. Other Cancers
7.5.1.3. Markers of Exposure or Susceptibility
7.5.2. Toxicological Studies
7.5.2.1. Mutagenesis and Genotoxicity
7.5.2.2. Carcinogenesis
7.5.2.3. Summary of Toxicological Studies
7.5.3. Epigenetic Studies and Other Heritable DMA mutations
7.5.4. Summary and Causal Determinations
7.5.4.1. PM,,
7.5.4.2. PMin.,,
7.5.4.3. UFPs
7.6. Mortality
7.6.1 . Recent Studies of Long-Term Exposure to PM and Mortality
7.6.2. Composition and Source-Oriented Analyses of PM
7.6.3. Within-City Effects of PM Exposure
7.6.4. Effects of Different Long-term Exposure Windows
7.6.5. Summary and Causal Determinations
7.6.5.1. PM,,
7.6.5.2. PMin.,,
7.6.5.3. UFPs
Chapter 7 References
CHAPTERS. POPULATIONS SUSCEPTIBLE TO PM-RELATED HEALTH EFFECTS
8.1. Potentially Susceptible Populations
8.1.1. Lifestaqe
8.1.1.1. Older Adults
8.1.1.2. Children
8.1.2. Pregnancy and Developmental Effects
8.1.3. Gender
8.1.4. Race/Ethnicity
8.1.5. Gene-Environment Interaction
8.1.6. Pre-Existing Disease
8. 1 .6. 1 . Cardiovascular Diseases
8.1.6.2. Respiratory Illnesses
8.1.6.3. Respiratory Contributions to Cardiovascular Effects
8.1.6.4. Diabetes and Obesity
8.1.7. Socioeconomic Status
8.1.8. Summary
Chapter 8 References
CHAPTER 9. WELFARE EFFECTS
9.1. Introduction
9.2. Effects on Visibility
9.2.1. Introduction
9.2.2. Backqround
9.2.2.1. Non-PM Visibility Effects
7-63
7-67
7-67
7-68
7-68
7-68
7-69
7-70
7-73
7-73
7-75
7-76
7-79
7-80
7-80
7-81
7-81
7-82
7-82
7-82
7-84
7-89
7-90
7-92
7-95
7-95
7-97
7-97
7-98
8-1
8-3
8-3
8-3
8-5
8-5
8-6
8-7
8-7
8-9
8-9
8-12
8-13
8-13
8-14
8-15
8-17
9-1
9-1
9-1
9-1
9-2
9-5
December 2009

-------
9.2.3.
9.2.4.
9.2.5.
9.3. Effects
9.3.1.
9.3.2.
9.3.3.
9.3.4.
9.3.5.
9.3.6.
9.3.7.
9.3.8.
9.3.9.
9.3.10.
9.2.2.2. PM Visibility Effects
9.2.2.3. Direct Optical Measurements
9.2.2.4. Value of Good Visual Air Quality
Monitoring and Assessment
9.2.3.1. Aerosol Properties
9.2.3.2. Spatial Patterns
9.2.3.3. Urban and Regional Patterns
9.2.3.4. Temporal Trends
9.2.3.5. Causes of Haze
Urban Visibility Valuation and Preference
9.2.4. 1 . Urban Visibility Preference Studies
9.2.4.2. Denver, Colorado Urban Visibility Preference Study
9.2.4.3. Phoenix, Arizona Urban Visibility Preference Study
9.2.4.4. British Columbia, Canada Urban Visibility Preference Study
9.2.4.5. Washington, DC Urban Visibility Preference Studies
9.2.4.6. Urban Visibility Valuation Studies
Summary of Effects on Visibility
on Climate
The Climate Effects of Aerosols
Overview of Aerosol Measurement Capabilities
9.3.2.1. Satellite Remote Sensing
9.3.2.2. Focused Field Campaigns
9.3.2.3. Ground-Based In Situ Measurement Networks
9.3.2.4. In Situ Aerosol Profiling Programs
9.3.2.5. Ground-Based Remote Sensing Measurement Networks
9.3.2.6. Synergy of Measurements and Model Simulations
Assessments of Aerosol Characterization and Climate Forcing
9.3.3.1. The Use of Measured Aerosol Properties to Improve Models
9.3.3.2. Intercomparisons of Satellite Measurements and Model Simulation of
Aerosol Optical Depth
9.3.3.3. Satellite-Based Estimates of Aerosol Direct Radiative Forcing
9.3.3.4. Satellite-Based Estimates of Anthropogenic Component of Aerosol
Direct Radiative Forcing
9.3.3.5. Aerosol-Cloud Interactions and Indirect Forcing
9.3.3.6. Remote Sensing of Aerosol-Cloud Interactions and Indirect Forcing
9.3.3.7. In Situ Studies of Aerosol-Cloud Interactions
Outstanding Issues
Concluding Remarks
Modeling the Effect of Aerosols on Climate
9.3.6.1. Introduction
9.3.6.2. Modeling of Atmospheric Aerosols
9.3.6.3. Calculating Aerosol Direct Radiative Forcing
9.3.6.4. Calculating Aerosol Indirect Forcing
9.3.6.5. Aerosol in the Climate Models
9.3.6.6. Impacts of Aerosols on Climate Model Simulations
9.3.6.7. Outstanding Issues
9.3.6.8. Conclusions
Fire as a Special Source of PM Welfare Effects
Radiative Effects of Volcanic Aerosols
9.3.8.1. Explosive Volcanic Activity
Other Special Sources and Effects
9.3.9.1. Glaciers and Snowpack
9.3.9.2. Radiative Forcing by Anthropogenic Surface Albedo Change: BC in
Snow and Ice
9.3.9.3. Effects on Local and Regional Climate
Summary of Effects on Climate
9-5
9-8
9-10
9-10
9-11
9-16
9-23
9-31
9-37
9-65
9-67
9-68
9-69
9-69
9-69
9-71
9-72
9-74
9-74
9-82
9-82
9-88
9-89
9-91
9-95
9-96
9-99
9-100
9-103
9-105
9-111
9-112
9-113
9-116
9-117
9-120
9-121
9-121
9-124
9-129
9-137
9-145
9-153
9-157
9-158
9-159
9-160
9-160
9-164
9-167
9-169
9-170
9-171
          9.4.  Ecological Effects of PM	9-172
December 2009                                        xii

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9.4.1. Introduction
9.4.1.1. Ecosystem Scale, Function, and Structure
9.4.1.2. Ecosystem Services
9.4.2. Deposition of PM
9.4.2. 1 . Forms of Deposition
9.4.2.2. Components of PM Deposition
9.4.2.3. Magnitude of Dry Deposition
9.4.3. Direct Effects of PM on Vegetation
9.4.3.1. Effects of Coarse-mode Particles
9.4.4. PM and Altered Radiative Flux
9.4.5. Effects of Trace Metals on Ecosystems
9.4.5.1. Effects on Soil Chemistry
9.4.5.2. Effects on Soil Microbes and Plant Uptake via Soil
9.4.5.3. Plant Response to Metals
9.4.5.4. Effects on Aquatic Ecosystems
9.4.5.5. Effects on Animals
9.4.5.6. Biomagnification across Trophic Levels
9.4.5.7. Effects near Smelters and Roadsides
9.4.5.8. Toxicity to Mosses and Lichens
9.4.6. Organic Compounds
9.4.7. Summary of Ecological Effects of PM
9.5. Effects on Materials
9.5.1. Effects on Paint
9.5.2. Effects on Metal Surfaces
9.5.3. Effects on Stone
9.5.4. Summary of Effects on Materials
Chapter 9 References
ANNEX A. ATMOSPHERIC SCIENCE
Annex A References
ANNEX B. DOSIMETRY
Annex B References
ANNEX C. CONTROLLED HUMAN EXPOSURE STUDIES
Annex C References
ANNEX D. TOXICOLOGICAL STUDIES
Annex D References
ANNEX E. EPIDEMIOLOGIC STUDIES
Annex E References
ANNEX F. SOURCE APPORTIONMENT STUDIES
Annex F References
9-172
9-173
9-174
9-174
9-175
9-175
9-179
9-182
9-182
9-183
9-183
9-185
9-186
9-189
9-192
9-192
9-193
9-194
9-196
9-196
9-199
9-201
9-202
9-202
9-203
9-203
9-204
A-1
A-353
B-1
B-7
C-1
C-14
D-1
D-172
E-1
E-524
F-1
F-11
December 2009                                          xiii

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                                       List  of  Tables
Table 1-1.         Summary of NAAQS promulgated for PM, 1971-2006.	1-6
Table 1 -2.         Aspects to aid in judging causality.	1 -20
Table 1-3.         Weight of evidence for causal determination.	1-22
Table 2-1.         Summary of causal determinations for short-term exposure to PM2 5.	2-36
Table 2-2.         Summary of causal determinations for long-term exposure to PM2 5.	2-38
Table 2-3.         Summary of causal determinations for short-term exposure to PM10.2.5.	2-45
Table 2-4.         Summary of causal determinations for short-term exposure to UFPs.	2-48
Table 2-5.         Summary of causality determination for welfare effects.	2-54
Table 2-6.         Summary of PM causal determinations by exposure duration and health outcome.	2-59
Table 2-7.         Summary of PM causal determinations for welfare effects	2-60
Table 3-1.         Characteristics of ambient fine (ultrafine plus accumulation-mode) and coarse particles.	3-4
Table 3-2.         Constituents of atmospheric particles and their major sources.	3-7
Table 3-3.         Proximity to PM2 5 and PM10 monitors for total population3 by city.	3-35
Table 3-4.         Proximity to PM2 5 and PM10 monitors for children age 0-4 yr, children  age 5-17 yr, and
                  adults age 65 yr and older.3 The figures presented here are cumulative for the 15
                  CSAs/CBSAs examined in Chapter 3.	3-37
Table 3-5.         Proximity to PM2 5 and PM10 monitors for adults age 65 yr and older3 by city.	3-38
Table 3-6.         Proximity to PM25 and PM10 monitors based on the population identified as white, black,
                  Hispanic, or non-Hispanic3.	3-39
Table 3-7.         Proximity to PM25 and PM10 monitors based on the population below or above the poverty
                  line, population over age 25 with less than high school education, population over 25 with
                  high school education, and population over 25 with college education  or more3.	3-40
Table 3-8.         PM25 distributions derived from AQS data (concentration in ug/m3).	3-44
Table 3-9.         PM10.2.5 distributions derived from AQS data (concentration in ug/m3).	3-47
Table 3-10.        PM10 distributions derived from AQS data (concentration in  ug/m3).	3-49
Table 3-11.        Inter-sampler comparison statistics for each pair of 24-h PM2 5 monitors reporting to AQS
                  for Boston, MA.	3-63
Table 3-12.        Inter-sampler comparison statistics for each pair of 24-h PM2 5 monitors reporting to AQS
                  for Pittsburgh, PA.	3-67
Table 3-13.        Inter-sampler comparison statistics for each pair of 24-h PM2 5 monitors reporting to AQS
                  for Los Angeles, CA.	3-69
Table 3-14.        Inter-sampler comparison statistics for each pair of 24-h PM10 monitors reporting to AQS for
                  Boston, MA.	3-75
Table 3-15.        Inter-sampler comparison statistics for each pair of 24-h PM10 monitors reporting to AQS for
                  Pittsburgh, PA.	3-78
Table 3-16.        Inter-sampler comparison statistics for each pair of 24-h PM10 monitors reporting to AQS for
                  Los Angeles, CA.	3-81
December 2009                                           xiv

-------
Table 3-1 7.
Table 3-1 8.
Table 3-1 9.
Table 3-20.
Table 3-21.
Table 3-22.
Table 3-23.
Table 3-24.
Table 4-1 .
Table 6-1 .
Table 6-2.
Table 6-3.
Table 6-4.
Table 6-5.
Table 6-6.
Table 6-7.
Table 6-8.
Table 6-9.
Table 6-10.
Table 6-11.
Table 6-1 2.
Table 6-1 3.
Table 6-1 4.
Table 6-1 5.
Example of emissions factors (ng/km) for trace elements under variable speed and steady
speed drivinq conditions for PM emitted bv diesel and qasoline engines.
Estimates of annual average natural background concentrations of PM2.5 and PM10 (ug/m3)
from Triionisetal. (1990, 157058).
Annual and quarterly mean PM2 5 concentrations (ug/m3) measured at IMPROVE sites in
2004.
Annual and quarterly mean PM2.5 concentrations (ug/m3) for the CMAQ "base case" at
IMPROVE sites in 2004.
Annual and quarterly mean PM2 5 concentrations (ug/m3) for the CMAQ PRB simulations at
IMPROVE sites in 2004.
Annual and quarterly mean of the CMAQ-predicted base case PM25 concentrations (ug/m3)
in the U.S. EPA CONUS reqions in 2004.
Annual and quarterly mean of the CMAQ-predicted PRB PM25 concentrations (ug/m3) in
the U.S. EPA CONUS reqions in 2004.
Examples of studies comparing near-road personal exposures with fixed site ambient
concentrations.
Breathing patterns with activity level in adult human male.
Characteristics of epidemiologic studies investigating associations between PM and
changes in HRV.
Epidemiologic studies of ventricular arrhythmia and ambient PM concentration, in patients
with implantable cardioverter defibrillators.
PM Concentrations reported in epidemiologic studies ECG changes suggestive of
ischemia.
PM concentrations reported in epidemioloqic studies of vasomotor function.
Mean PM concentrations reported in epidemioloqic studies of blood pressure.
PM concentrations reported in epidemiologic studies of inflammation, hemostasis,
thrombosis, coagulation factors and oxidative stress.
Description of ICD-9 and ICD-10 codes for diseases of the circulatory system.
Characterization of ambient PM concentrations in epidemiologic studies of hospital
admission and ED visits for cardiovascular diseases.
PM concentrations reported in studies of out-of-hospital cardiac arrest.
Characterization of ambient PM concentrations from epidemiologic studies of respiratory
morbidity and short-term exposures in asthmatic children and adults.
PAMCHAR PMm-?
-------
Table 6-17.        Effect modification of composition on the estimated percent increase in mortality with a 10
                  |jg/m3 increase in PM2.5.	6-194
Table 6-18.        Study-specific PM2.5 factor/source categories associated with health effects.	6-207
Table 7-1.         Characterization of ambient PM concentrations from studies of subclinical measures of
                  cardiovascular diseases and long-term exposure.	7-11
Table 7-2.         Characterization of ambient PM concentrations from studies of clinical cardiovascular
                  diseases and long-term exposure.	7-14
Table 7-3.         Characterization of ambient PM concentrations from studies of respiratory
                  symptoms/disease and long-term exposures.	7-22
Table 7-4.         Characterization of ambient PM concentrations from studies of FEVi and long-term
                  exposures.	7-27
Table 7-5.         Characterization of ambient PM concentrations from studies of reproductive,
                  developmental, prenatal and neonatal outcomes and long-term exposure.	7-46
Table 7-6.         Characterization of ambient PM concentrations from recent studies of cancer and long-term
                  exposures to PM.	7-70
Table 7-7.         Associations* between ambient PM concentrations from select studies of lung cancer
                  mortality and incidence.	7-72
Table 7-8.         Characterization of ambient PM concentrations from studies of mortality and long-term
                  exposures to PM.	7-83
Table 7-9.         Comparison of results from ACS intra-urban analysis of Los Angeles and New York City
                  using kriging or land use regression to estimate exposure.	7-91
Table 7-10.        Distribution of the effect of a hypothetical reduction of 10 ug/m3 PM10 in 2000 on all-cause
                  mortality 2000-2009 in Switzerland.	7-94
Table 8-1.         Definitions of susceptible and vulnerable in the PM literature.	8-2
Table 8-2.         Susceptibility factors evaluated.	8-3
Table 8-3.         Percent of the U.S. population with respiratory  diseases, cardiovascular diseases, and
                  diabetes.	8-11
Table 9-1.         Regional Planning Organization websites with visibility characterization and source
                  attribution assessment information.	9-17
Table 9-2.         Summary of urban visibility preference studies.	9-67
Table 9-3.         Top-of-atmosphere, cloud-free, instantaneous direct aerosol radiative forcing dependence
                  on aerosol and surface properties.	9-81
Table 9-4.         Summary of major satellite measurements currently available for the tropospheric aerosol
                  characterization and radiative forcing research.	9-83
Table 9-5.         List of major intensive field experiments that are relevant to aerosol research in a variety of
                  aerosol regimes around the globe conducted in the past two decades.	9-93
Table 9-6.         Summary of major U.S. surface in situ and remote sensing networks for the tropospheric
                  aerosol characterization and radiative forcing research.	9-94
Table 9-7.         Summary of approaches to estimating the  aerosol direct radiative forcing in three
                  categories: (1) satellite retrievals; (2) satellite-model integrations; and (3) model
                  simulations.	9-106
Table 9-8.         Summary of seasonal and annual average clear-sky DRF (W/m2) at the TOA and the
                  surface (SFC) over global OCEAN derived with different methods and data.	9-109
December 2009                                            xvi

-------
Table 9-9.


Table 9-10.


Table 9-11.

Table 9-12.

Table 9-13.


Table 9-14.
Summary of seasonal and annual average clear-sky DRF (W/m ) at the TOA and the
surface (SFC) over global LAND derived with different methods and data.	
Estimates of anthropogenic components of aerosol optical depth (Tant) and clear-sky DRF
at the TOA from model simulations.
Anthropogenic emissions of aerosols and precursors for 2000 and 1750.
Summary of statistics of AeroCom Experiment A results from 16 global models..
   , 2- .
S04   mass loading, MEE and AOD at 550 nm, shortwave radiative forcing at the top of the
atmosphere, and normalized forcing with respect to AOD and mass.	
Particulate organic matter (POM) and BC mass loading, AOD at 550 nm, shortwave
radiative forcing at the top of the atmosphere, and normalized forcing with respect to AOD
and mass.
_9-126

_9-127
                                                                                                            9-132
Table 9-1 5.
Table 9-1 6.
Table 9-1 7.
Table 9-1 8.
Table 9-1 9.
Table 9-20.
Table 9-21.
Table A-1 .
Table A-2.
Table A-3.
Table A-4.
Table A-5.
Table A-6.
Table A-7.
Table A-8.
Table A-9.
Table A-1 0.
Table A-1 1.
Table A-1 2.
Table A-1 3.
Table A-1 4.
Table A-1 5.
Differences in present day and pre-industrial outgoing solar radiation (W/m2) in the different
experiments.
Forcinqs used in IPCC AR4 simulations of 20th century climate chanqe.
Climate forcings (1880-2003) used to drive GISS climate simulations, along with the
surface air temperature changes obtained for several periods.
Overview of the different aerosol indirect effects and their sign of the net radiative flux
chanqe at the top of the atmosphere (TOA).
Overview of the different aerosol indirect effects and their implications for the global mean
net shortwave radiation of the surface Fsfc (columns 2-4) and for precipitation (columns
5-7).
Recent studies hiqhliqhtinq POP occurrence and fate in the maior arctic compartments.
Factors potentially important in estimatinq Hq exposure.
Summary of inteqrated and continuous samplers included in the field comparison.
Summary of PM?^ and PMm FRMand FEM samplers.
Measurement and analytical specifications for filter analysis of mass, elements, ions, and
carbon.
Measurement and analytical specifications for filter analysis of orqanic species.
Measurement and analytical specifications for continuous mass and mass surrogate
instruments.
Measurement and analytical specifications for continuous elements.
Measurement and analytical specifications for continuous N0r.
Measurement and analytical specifications for continuous Sd2".
Measurement and analytical specifications for ions other than NOf and Sd2".
Measurement and analytical specifications for continuous carbon.
Summary of mass measurement comparisons.
Summary of element and liquid water content measurement comparisons.
Summary of PM? ^ NOV measurement comparisons.
Summary of PM? ^ Sd2" measurement comparisons
Summary of PM? $ carbon measurement comparisons.
9-141
9-145
9-154
9-166
9-166
9-168
9-177
A-1
A-5
A-7
A-9
A-11
A-1 4
A-1 5
A-1 7
A-1 9
A-20
A-23
A-31
A-32
A-38
A-41
December 2009
                                                       XVII

-------
TableA-16.
TableA-17.
TableA-18.
TableA-19.
Table A-20.
Table A-21.
Table A-22.
Table A-23.
Table A-24.
Table A-25.
Table A-26.
Table A-27.
Table A-28.
Table A-29.
Table A-30.
Table A-31.
Table A-32.
Table A-33.
Table A-34.
Table A-35.
Table A-36.
Table A-37.
Table A-38.
Summary of particle mass spectrometer measurement comparisons.
Summary of key parameters for TD-GC/MS and pyrolysis-GC/MS.
Relevant Spatial Scales for PMm, PM^, and PMm-?<; Measurement
Maior routine operatinq air monitorinq networks3
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Atlanta, GA.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Birminqham, AL.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Boston, MA.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Chicaqo, IL.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Denver, CO.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Detroit, Ml.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Houston, TX.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for Los
Anqeles, CA.
Inter-sampler correlation statistics for each pair of PM25 monitors reporting to AQS for New
York, NY.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Philadelphia, PA.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Phoenix, AZ.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Pittsburgh, PA.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Riverside, CA.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
Seattle, WA.
Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for St.
Louis, MO.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Atlanta, GA.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Birminqham, AL.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Boston, MA.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Chicaqo, IL.
A-48
A-52
A-54
A-56
A-98
A-102
A-106
A-111
A-116
A-120
A-123
A-127
A-131
A-136
A-140
A-144
A-148
A-152
A-155
A-159
A-163
A-166
A-170
December 2009
                                                      XVIII

-------
Table A-39.
Table A-40.
Table A-41.
Table A-42.
Table A-43.
Table A-44.
Table A-45.
Table A-46.
Table A-47.
Table A-48.
Table A-49.
Table A-50.
Table A-51.
Table A-52.
Table A-53.
Table A-54.
Table A-55.
Table A-56.
Table A-57.
Table A-58.
Table A-59.
Table A-60.
Table A-61.
Table A-62.
Table A-63.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Denver, CO.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Detroit, Ml.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Houston, TX.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for Los
Anqeles, CA.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for New
York, NY.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Philadelphia, PA.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Phoenix, AZ.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Pittsburgh, PA.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Riverside, CA.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for
Seattle, WA.
Inter-sampler correlation statistics for each pair of PM10 monitors reporting to AQS for St.
Louis, MO.
Correlation coefficients of hourly and daily average particle number, surface and volume
concentrations in selected particle size ranges.
Different receptor models used in the Supersite source apportionment studies: chemical
mass balance.
Different receptor models used in the Supersites source apportionment studies: factor
analysis.
Different receptor models used in the Supersites source apportionment studies: tracer-
based methods.
Different receptor models used in the Supersites source apportionment studies:
meteorology-based methods.
Source Profiles: Part I
PM7^ receptor model results (pg/m3)
PMm receptor model results (mass percent)
Exposure Assessment Study Summaries
Examples of studies showing developments with UFP sampling methods since the 2004
PMAQCD.
Summary of in-vehicle studies of exposure assessment.
Summary of personal PM exposure studies with no indoor source during 2002-2008.
Summary of PM species exposure studies.
Summary of personal PM exposure source apportionment studies.
A-174
A-178
A-181
A-184
A-188
A-191
A-195
A-200
A-204
A-207
A-211
A-212
A-273
A-274
A-278
A-280
A-286
A-289
A-290
A-291
A-317
A-318
A-320
A-324
A-337
December 2009
                                                     XIX

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Table A-64.
Table A-65.
Table B-1 .
Table B- 2.
Table B- 3.
Table B-4.
Table B-5.
Table C-1.
Table C-2.
Table C- 3.
Table D-1.
Table D-2.
Table D-3.
Table D-4.
Table D-5.
Table D-6.
Table D-7.
Table D-8.
Table E-1
Table E-2.
Table E-3.
Table E-4.
Table E-5.
Table E-6.
Table E-7.
Table E-8.
Table E-9.
Table E-1 0.
Table E-1 1.
Table E-1 2.
Table E-1 3.
Table E-1 4.
Table E-1 5.
Table E-1 6.
Table E-1 7.
Summary of PM infiltration studies.
Summary of PM - copollutant exposure studies.
Ultrafine disposition in humans.
Ultrafine disposition in animals.
In vitro studies of ultrafine disposition.
Olfactory particle translocation.
Studies of respiratory tract mucosal and macrophaqe clearance as a function of aqe.
Cardiovascular effects.
Respiratory effects.
Central nervous system effects.
Cardiovascular effects.
Respiratory effects: in vitro studies.
Respiratory effects: in vivo studies.
Effects related to immunity and allerqy.
Effects of the central nervous system.
Reproductive and developmental effects.
Mutaqenic/qenotoxic effects in bacterial cultures.
Mutaqenicity and qenotoxicity data summary: In vitro and in vivo.
Short-term exposure - cardiovascular morbidity outcomes: PMm
Short-term exposure - cardiovascular morbidity studies: PMio-2.5.
Short-term exposure - cardiovascular morbidity studies: PlVhs (including PM
components/sources).
Short-term exposure-cardiovascular morbidity studies: Other size fractions.
Short-term exposure-cardiovascular: ED/HA PMm
Short-term exposure-cardiovascular-ED/HA - PMin.?^.
Short-term exposure - cardiovascular: ED/HA PM?^ (includinq PM components/sources)
Short-term exposure-cardiovascular-ED/HA-other size fractions.
Short-term exposure-respiratory morbidity outcomes -PMio.
Short-term exposure - respiratory morbidity outcomes - PMio-2.5.
Short-term exposure - respiratory morbidity outcomes - PM2 5 (including
components/sources).
Short-term exposure-respiratory-ED/HA-PMio.
Short-term exposure-respiratory-ED/HA-PMio-2.5.
Short-term exposure-respiratory-ED/HA-PMzs (includinq PM components/sources).
Short-term exposure-respiratory-ED/HA-Other Size Fractions.
Short-term exposure-mortality - PMio.
Short-term exposure-mortality - PMio-2.5.
A-339
A-350
B-1
B-2
B-3
B-3
B-5
C-1
C-9
C-1 3
D-1
D-31
D-81
D-1 16
D-1 55
D-1 57
D-1 63
D-1 66
E-1
E-1 9
E-21
E-79
E-85
E-1 04
E-1 07
E-1 30
E-1 34
E-1 69
E-1 73
E-230
E-256
E-262
E-284
E-293
E-343
December 2009                                        xx

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TableE-18.
TableE-19.
Table E-20.
Table E-21.
Table E-22.
Table E-23.
Table E-24.
Table E-25.
Table E-26.
Table E-27.
Table E-28.
Table E-29.
Table E-30.
Table E-31.
Table E-32.
Table E-33.
Table E-34.
Table F-1 .
Table F-2.
Table F-3.
Short-term exposure-mortality - PM^ (includinq PM components/sources).
Short-term exposure-mortality - other PM size fractions.
Lonq-term exposure - cardiovascular morbidity outcomes - PMm.
Lonq-term effects-cardiovascular- PMzs (includinq PM components/sources).
Lonq-term exposure - respiratory morbidity outcomes - PMm.
Lonq-term exposure - respiratory morbidity outcomes - PMm-zs.
Long-term exposure - respiratory morbidity outcomes - PMz.5 (including PM
components/sources).
Lonq-term exposure - respiratory morbidity outcomes - other PM size fractions.
Lonq-term exposure - cancer outcomes - PMm.
Lonq-term exposure - cancer outcomes - PMz.5 (includinq PM components/sources).
Lonq-term exposure - cancer outcomes - other PM size fractions.
Lonq-term exposure - reproductive outcomes - PMm.
Lonq-term exposure-mortality - PMm.
Lonq-term exposure-mortality - PMm.
Lonq-term exposure-mortality - PMio-2.5.
Lonq-term exposure-mortality - PMzs (includinq PM components/sources).
Lonq-term exposure - central nervous system outcomes - PM.
Epidemioloqic studies of ambient PM sources, factors, or constituents
Human clinical studies of ambient PM sources, factors, or constituents
Toxicoloqical studies of ambient PM sources, factors, or constituents
E-346
E-360
E-363
E-372
E-383
E-407
E-412
E-432
E-434
E-437
E-440
E-441
E-491
E-498
E-499
E-500
E-521
F-1
F-6
F-7
December 2009                                         xxi

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                List of Figures
Figure 1-1.
Figure 2-1 .
Figure 2-2.
Figure 2-3.
Figure 3-1 .
Figure 3-2.
Figure 3-3.
Figure 3-4.
Figure 3-5.
Figure 3-6.
Figure 3-7.
Figure 3-8.
Figure 3-9.
Figure 3-10.
Figure 3-11.
Figure 3-1 2.
Figure 3-1 3.
Figure 3-1 4.
Figure 3-1 5.
Figure 3-1 6.
Figure 3-1 8.
Identification of studies for inclusion in the ISA.
Summary of effect estimates (per 10 ug/m3) by increasing concentration from U.S. studies
examining the association between short-term exposure to PM25 and cardiovascular and
respiratory effects, and mortality
Summary of effect estimates (per 10 ug/m3) by increasing concentration from U.S. studies
examining the association between long-term exposure to PM25 and cardiovascular and
respiratory effects, and mortality
Summary of U.S. studies examining the association between short-term exposure to PM10.
?<; and cardiovascular morbidity/mortality and respiratory morbidity/mortality
Particle size distributions by number and volume.
X-ray spectra and scanning electron microscopy images of individual particles.
Detailed source categorization of anthropogenic emissions of primary PM2.5, PM10 and
gaseous precursor species S02, NOX, NH3 and VOCs for 2002 in units of million metric
tons (MMT).
Primary emissions and formation of SOA through gas, cloud and condensed phase
reactions.
Schematic of the resistance-in-series analogy for atmospheric deposition.
The relationship between particle diameter and Vri for particles.
PM?<; monitor distribution in comparison with population density, Boston CSA.
PMm monitor distribution in comparison with population density, Boston CSA.
Three-yr avg 24-h PM25 concentration by county derived from FRM or FRM-like data,
2005-2007.
Three-yr avg 24-h PM10.2.5 concentration by county derived from co-located low volume
FRM PMm and PM,^ monitors, 2005-2007.
Three-yr avg 24-h PM10 concentration by county derived from FRM or FEM monitors,
2005-2007.
Three-yr avg 24-h PM25 OC concentrations measured at CSN sites across the U.S., 2005-
2007.
Three-yr avg 24-h PM25 EC concentrations measured at CSN sites across the U.S., 2005-
2007.
Three-yr avg 24-h PM25 S042" concentrations measured at CSN sites across the U.S.,
2005-2007.
Three-yr avg 24-h PM25 N03" concentrations measured at CSN sites across the U.S.,
2005-2007.
Three-yr avg 24-h PM25 NH4+ concentrations measured at CSN sites across the U.S.,
2005-2007.
Seasonally-stratified 3-yr avg PM2 5 speciation estimates for 2005-2007 derived using the
SANDWICH method.
1-11
2-41
2-42
2-47
3-2
3-5
3-9
3-12
3-15
3-19
3-33
3-34
3-43
3-46
3-48
3-52
3-53
3-54
3-55
3-56
3-58
December 2009                  xxii

-------
Figure 3-1 9.
Figure 3-20.
Figure 3-21.
Figure 3-22.
Figure 3-23.
Figure 3-24.
Figure 3-25.
Figure 3-26.
Figure 3-27.
Figure 3-28.
Figure 3-29.
Figure 3-30.
Figure 3-31.
Figure 3-32.
Figure 3-33.
Figure 3-34.
Figure 3-35.
Figure 3-36.
Figure 3-37.
Figure 3-38.
Figure 3-39.
Figure 3-40.
Figure 3-41 .
Locations of PM,^ monitors and maior highways, Boston, MA.
Seasonal distribution of 24-h avq PM^ concentrations bv site for Boston, MA, 2005-2007.
Locations of PM?^ monitors and maior highways, Pittsburgh, PA.
Seasonal distribution of 24-h avg PM25 concentrations by site for Pittsburgh, PA, 2005-
2007.
Locations of PM? ^ monitors and maior highways, Los Angeles, CA.
Seasonal distribution of 24-h avg PM2 5 concentrations by site for Los Angeles, CA, 2005-
2007.
Inter-sampler correlations for 24-h PM2 5 as a function of distance between monitors in
Boston, MA.
Inter-sampler correlations for 24-h PM2 5 as a function of distance between monitors in
Pittsburgh, PA.
Inter-sampler correlations for 24-h PM2 5 as a function of distance between monitors in Los
Angeles, CA.
Seasonal distribution of 24-h avg PMm-?<; concentrations by site
Locations of PMm monitors and maior highways, Boston, MA.
Seasonal distribution of 24-h avg PMm concentrations by site for Boston, MA, 2005-2007.
Locations of PMm monitors and maior highways, Pittsburgh, PA.
Seasonal distribution of 24-h avg PM10 concentrations by site for Pittsburgh, PA, 2005-
2007.
Locations of PMm monitors and maior highways, Los Angeles, CA.
Seasonal distribution of 24-h avg PM10 concentrations by site for Los Angeles, CA, 2005-
2007.
Inter-sampler correlations for 24-h PM10 as a function of distance between monitors in
Boston, MA.
Inter-sampler correlations for 24-h PM10 as a function of distance between monitors in
Pittsburgh, PA.
Inter-sampler correlations for 24-h PM10 as a function of distance between monitors in Los
Angeles, CA.
Bin-wise Spearman correlation coefficients in aerosol particle number concentrations
between the Ift (urban background) and the Eisenbahn-strasse (city/urban center) sites in
Leipzig, Germany.
Dimensionless concentration as a function of height at windward and leeward locations and
street canyon aspect ratios (H/W).
Inter-sampler correlations for 24-h PM2 5 and PM10 as a function of distance between
monitors for samplers located within 4 km (neighborhood scale).
Particle size distributions measured at various distances from the 71 0 freeway in Los
3-61
3-62
3-65
3-66
3-68
3-69
3-71
3-71
3-72
3-73
3-74
3-75
3-76
3-77
3-80
3-81
3-82
3-83
3-83
3-84
3-86
3-87

                  Angeles, CA (top), and particle number concentration as a function of distance from the
                  710 freeway (bottom).	3-88

Figure 3-42.       Mass distributions for BaP at a high traffic urban center (HTC), high traffic urban periphery
                  (HTP), low traffic urban center (LTC), low traffic urban periphery (LTP), and low traffic
                  industrial urban periphery (LTIP) in Seville, Spain.	3-90
December 2009                                            xxiii

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Figure 3-43.        Mass distributions for 16 PAHs at a high traffic city center in Seville, Spain.	3-91

Figure 3-44.        Ambient 24-h PM2.5 concentrations in the U.S., 1999-2007, showing A) ambient
                  concentrations, B) number of trends sites above the 24-h NAAQSand C) trends by U.S.
                  EPA Region.	3-92

Figure 3-45.        Ambient annual PM2.5 concentrations in the U.S., 1999-2007, showing A) ambient
                  concentrations, B) number of trends sites above the annual NAAQS and C) trends by U.S.
                  EPA Region.	3-93

Figure 3-46.        Ambient 24-h PM10 concentrations in the U.S., 1988-2007, showing A) ambient
                  concentrations, B) number of trends sites above the 24-h NAAQSand C) trends by U.S.
                  EPA Region.	3-94

Figure 3-47.        Regional and seasonal trends in annual PM2 5 compostion from 2002 to 2007 derived using
                  the SANDWICH method.	3-95

Figure 3-48.        UFP size distribution at highway (site A) and background (site B) sites in Los Angeles, CA,
                  during summer and winter seasons, with winter broken into day and evening distributions.	3-97

Figure 3-49.        Diel plot generated from hourly FRM-like PM2.5 data ()4)/m3) stratified by weekday (left) and
                  weekend (right) for Pittsburgh, PA, and Seattle, WA, 2005-2007.	3-98

Figure 3-50.        Diel plots generated from hourly FEM PM10 data ()4)/m3) stratified by weekday (left) and
                  weekend (right) for Chicago, IL, and Phoenix,  AZ, 2005-2007.	3-99

Figure 3-51.        Average diel variation in total particle number  (ToN) and total particle volume (ToV) on
                  weekdays (left column) and Sundays (right column) from two sites in Denmark: one in a
                  busy street canyon (Jagtv) and one measuring urban background (HC0).	3-100

Figure 3-52.        Distribution of correlations between 24-h avg PM25 and co-located 24-h avg PM10, PM10.2.5,
                  S02, N02 and CO and daily max 8-h avg 03 for the U.S. stratified by season (2005-2007).	3-101

Figure 3-53.        Distribution of correlations between 24-h avg PM10 and co-located 24-h  avg PM25, PM10.2.5,
                  S02, N02 and CO and daily max 8-h avg 03 for the U.S. stratified by season (2005-2007).	3-102

Figure 3-54.        Schematic of organic composition of particulate emissions from gasoline-fueled vehicles.	3-105

Figure 3-55.        Source category contributions to PM2 5  at a number of sites in the East derived using PMF.	3-108

Figure 3-56.        Pearson correlation coefficients for source category contributions to PM2 5 between the 10
                  Regional Air Pollution Study/Regional Air Monitoring System  (RAPS/RAMS) monitoring
                  sites in St. Louis.	3-109

Figure 3-57.        Pearson correlation coefficients for source contributions to PM10.2.5 between the 10
                  Regional Air Pollution Study/Regional Air Monitoring System  (RAPS/RAMS) monitoring
                  sites in St. Louis.	3-109

Figure 3-58.        Eight km southeast U.S. CMAQ-UCD domain  zoomed over Tampa Bay, FL.	3-115

Figure 3-59.        Two km southeast U.S. CMAQ-UCD domain zoomed over Tampa Bay,  FL.	3-115

Figure 3-60.        Hourly average CMAQ-UCD predictions and measured observations of NO (top),  N02
                  (middle), and total NOX (bottom) concentrations for May 1 -31, 2002.	3-116

Figure 3-61.        CMAQ-UCD predictions and measured observations of ethene concentrations at Sydney,
                  FL for May 1-31, 2002.	3-117

Figure 3-62.        CMAQ-UCD predictions and measured observations of isoprene concentrations at Sydney,
                  FL for May 1-31, 2002.	3-118

Figure 3-63.        CMAQ-UCD predictions and measured observations of PM25 concentrations at Sidney, FL
                  for May 1 -31, 2002.	3-119
December 2009                                           xxiv

-------
Figure 3-64.
Figure 3-65.
Figure 3-66.
Figure 3-67.
Figure 3-68.
Figure 3-69.
Figure 3-70.
Figure 3-71.
Figure 3-72.
Figure 3-73.
Figure 3-74.
Figure 3-75.
Figure 3-76.
Figure 3-77.
Figure 3-78.
Figure 3-79.
Figure 3-80.
Figure 3-81.
Figure 3-82.
Figure 3-83.
Figure 3-84.
Figure 3-85.
Figure 3-86
Figure 3-87.
CMAQ-UCD predictions of HN03 concentrations and corresponding measured
observations at Sydney, FL, for May 1 -31 , 2002.
CMAQ-UCD predictions of NH3 concentrations and corresponding measured observations
at Sydney, FL, for May 1-31, 2002.
CMAQ-UCD predictions of pN03" concentrations and corresponding measured
observations at Sydney, FL, for 1-31 May, 2002.
CMAQ-UCD predictions of the ratio of HN03 to total N03 and corresponding measured
observations at Sydney, FL, for May 1 -31 , 2002.
CMAQ-UCD predicted size and chemical-form fractions of total N03" for days in May 2002
with measured observations.
Scatter plot of total nitrate (HN03 plus pN03") wet deposition (mg N/m2/yr) of the model
mean versus measurements for the North American Deposition Proqram (NADP) network.
Scatter plot of total S042" wet deposition (mg S/m2/yr) of the model mean versus
measurements for the National Atmospheric Deposition Proqram (NADP) network.
CMAQ modeling domains for the OAQPS risk and exposure assessments: 36 km outer
parent domain in black; 12 km western U.S. (WUS) domain in red; 12 km eastern U.S.
(EUS) domain in blue.
12-km EUS Summer sulfate PM.
12-km EUS Winter nitrate PM.
12-km EUS Winter total nitrate (HNCK + total pNOO.
12-km EUS annual sulfate wet deposition.
12-km EUS annual nitrate wet deposition.
CMAQ vs. measured air concentrations from east-coast sites in the IMPROVE, CSN
(labeled STN), and CASTNet sites in the summer of 2002 for sulfate (left) and ammonium
(riant).
Comparison of CMAQ-predicted and NADP-measured NH/ wet deposition
CMAQ-predicted (red symbols and lines) and 12-h measured (blue symbols and lines) NH3
and S042" surface concentrations at high and low concentration grid cells in North Carolina
in July 2004.
Surface grid cell (layer 1) analysis of the sensitivity of NHX deposition and transport to the
chanqe in NH3 Vri in CMAQ.
Total column analysis for NH3 (left) and NHX (right) showing modeled NH3 emissions,
transformation, and transport throuqhout the mixed layer and up to the free troposphere.
Range of influence (where 50% of emitted NH3 deposits) from the high concentration
Sampson County qrid cell in the June 2002 CMAQ simulation of Vri sensitivities.
Areal extent of the change in NHX range of influence as predicted by CMAQ for the
Sampson County high concentration grid cell (center of range circles) in June 2002 using
the base case and sensitivity case Vri.
IMPROVE monitorinq site locations.
12-km EUS Summer S042"PM.
12-km EUS Winter NOV PM.
12-km EUS Winter total nitrate (HN03 + total particulate N03").
3-121
3-122
3-123
3-124
3-125
3-127
3-127
3-128
3-129
3-130
3-131
3-132
3-133
3-134
3-134
3-135
3-136
3-136
3-137
3-138
3-141
3-144
3-145
3-145
December 2009                                        xxv

-------
Figure 3-88.
Figure 3-89.
Figure 3-90.
Figure 3-91 .
Figure 3-92.
Figure 3-93.
Figure 3-94.
Figure 3-95.
Figure 3-96.
Figure 3-97.
Figure 3-98.
Figure 3-99.
Figure 3-1 00.
Figure 3-1 01.
Figure 4-1 .
Figure 4-2.
Figure 4-3.
Monthly average of PM25 concentrations measured at IMPROVE sites in the East and
Midwest for 2004.
Monthly average of PM2.5 concentrations measured at IMPROVE sites in the West for
2004.
Distribution of PM2 5 concentrations measured at IMPROVE sites in the East and Midwest
for 2004.
Distribution of PM^ concentrations measured at IMPROVE sites in the West for 2004.
Model of total personal exposure to PM as a function of ambient and nonambient sources.
Distribution of time sample population spends in various environments, from the National
Human Activity Pattern Survey.
Total exposure to S042" as a function of measured ambient S042" concentration, from the
Vancouver study.
Estimated ambient exposure to PM2 5 as a function of measured ambient PM2 5
concentration, from the Vancouver study
Total exposure to PM2 5 as a function of measured ambient PM2 5 concentration, from the
Vancouver study.
Finf as a function of particle size.
Apportionment of aliphatic carbon, carbonyl, and S042" components of outdoor, indoor, and
personal PM?^ samples, for Los Anqeles (top), Elizabeth (center), and Houston (bottom).
Apportionment of infiltrated PM from mechanical generation (top), primary combustion
(center), and secondary combustion (bottom).
Results of the positive matrix factorization model showing differences in the mass of
outdoor PM and PM that has infiltrated indoors based on source category.
Grid resolution of the CMAQ model in Philadelphia compared with distribution of census
tracts in which exposure assessment is performed.
Diaqrammatic representation of respiratory tract regions in humans.
Structure of lower airways with progression from the large airways to the alveolus.
Comparison of total and regional deposition results from the ICRP and MPPD models for a
resting breathing pattern (VT = 625 ml, f = 12 min"1) and corrected for particle inhalability.
3-146
3-147
3-148
3-149
3-154
3-159
3-166
3-166
3-167
3-170
3-172
3-173
3-174
3-178
4-3
4-4
4-7
Figure 4-4.         Comparison of total and regional deposition results from the ICRP and MPPD models for a
                  light exercise breathing pattern (VT = 1250 ml, f = 20 min"1) and corrected for particle
                  inhalability.	4-8
Figure 4-5.         Total lung deposition measured in healthy adults (UF, 11 M, 11  F, 31 ± 4 yr; fine and
                  coarse, 11 M, 11 F, 25 ± 4 yr) during controlled breathing on a mouthpiece.	4-9
Figure 4-6.         Total deposition of hygroscopic sodium chloride and hydrophobic aluminosilicate aerosols
                  during  oral breathing (VT= 1.0 L; f = 15 min"1).	4-16
Figure 4-7.         Retention of poorly soluble particles (0.5-5 urn) in the alveolar region of the lung over time
                  in various mammalian species.	4-20
Figure 5-1.         PM oxidative potential.	5-2
Figure 5-2         PM stimulates pulmonary cells to produce ROS/RNS.	5-3
Figure 5-3.         PM activates cell signaling pathways leading to pulmonary inflammation.	5-5
Figure 5-4.         Potential pathways for the effects of PM on the respiratory system.	5-7
December 2009                                            xxvi

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Figure 5-5.         Potential pathways for the effects of PM on the cardiovascular system.	5-13
Figure 6-1.         Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.5, PM10.2.5, and PM10
                  concentration for CVD ED visits and HAs.                                                          6-62
Figure 6-2.         Excess risk estimates per 10 ug/m3 increase in 24-h avg (unless otherwise noted) PM2.5,
                  PM10.2.5, and PM10 concentration for Ml and IHD ED visits and HAs.	6-66

                  Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.5, PM10.2.5, and PM10
                  concentration for CHF ED visits and HAs.                                                          6-69
Figure 6-4.         Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2 5 and PM10 concentration for
                  CBVD ED visits and HAs.	6-72

Figure 6-5.         Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.5, and PM10.2.5 for
                  cardiovascular disease ED visits or HAs, adjusted for co-pollutants.	6-74

Figure 6-6.         Combined random-effect estimate of the concentration-response relationship between Ml
                  emergency hospital admissions and PM10, computed by fitting a piecewise linear spline,
                  with slope changes at 20 ug/m3 and 50 ug/m3.	6-76

Figure 6-7.         Respiratory symptoms and/or medication use among asthmatic children following acute
                  exposure to PM.	6-86

Figure 6-8.         Respiratory symptoms and/or medication use among asthmatic adults following acute
                  exposure to particles.	6-92

Figure 6-9.         Respiratory symptoms following acute exposure to particles and additional criteria
                  pollutants.	6-93

Figure 6-10.        Excess risk estimates per 10 ug/m3 24-h avg PM2.5, PM10.2.5, and PM10 concentration for
                  ED visits and HAs for respiratory diseases in children.	6-134

Figure 6-11.        Excess risks estimates per 10 ug/m3 increase in 24-h avg PM2.5, PM10.2.5, and PM10forED
                  visits and HAs for respiratory diseases among adults.	6-138

Figure 6-12.        Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.5, PM10.2.5, and PM10 for
                  asthma ED visits and HAs.	6-140

Figure 6-13.        Excess risks estimates per 10 ug/m3 increase in 24-h avg PM2.5, PM10.2.5, and PM10 for
                  COPD ED visits and HAs among older adults (65+ yr, unless other age group is noted).	6-143

 Figure 6-14.       Excess risks estimates per 10 ug/m3 increase in 24-h avg PM2.5, PM10.2.5, and PM10 for
                  respiratory infection ED visits* and HAs.	6-145

Figure 6-15.        Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.5, and PM10.2.5 for respiratory
                  disease  ED visits or HAs, adjusted for co-pollutants.	6-148

Figure 6-16.        National and regional estimates of smooth seasonal effects for PM10 at a 1 -day lag and
                  their sensitivity to the degrees of freedom assigned to the smooth function of time in the
                  updated NMMAPS data 1987-2000.	6-162

Figure 6-17.        Percent  increase in the daily number of deaths, for all ages, associated with a 10-ug/m3
                  increase in  PM10: lag 1  (A) and lags 0 and 1 (B) for all three centers.	6-166

Figure 6-18.        Effect modification by city characteristics in 20 U.S. cities.	6-168

Figure 6-19.        Percent  excess risk in mortality (all-cause [nonaccidental] and cause-specific) per
                  10 ug/m3increase in PM10by individual-level characteristics.	6-170

Figure 6-20.        Percent  excess risk in mortality (all-cause [nonaccidental] and cause-specific) per
                  10 ug/m3increase in PM10 by location of death and by season.	6-171
December 2009                                            xxvii

-------
Figure 6-21.        Percent increase in mortality (all-cause [nonaccidental] and cause-specific) per 10 ug/m3
                  increase in PM10 by contributing causes of death.	6-172
Figure 6-22.        Summary of percent increase in all-cause (nonaccidental) mortality from recent multicity
                  studies per 10 ug/m3 increase in PM10.	6-174
Figure 6-23.        Percent increase in all-cause (nonaccidental) and cause-specific mortality per 10 ug/m3
                  increase in the average of 0- and 1-day lagged PM25, combined by climatic regions.	6-177
Figure 6-24.        Empirical Bayes-adjusted city-specific percent increase in total (nonaccidental),
                  cardiovascular, and respiratory  mortality per 10 ug/m3 increase in the average of 0- and 1-
                  day lagged PM2.5 by decreasing mean 24-h avg PM2.5 concentrations.	6-178
Figure 6-25.        Summary of percent increase in all-cause (nonaccidental) mortality per 10 ug/m3 increase
                  in PM2.5 by various effect modifiers.	6-181
Figure 6-26.        Summary of percent increase in all-cause (nonaccidental) and cause-specific mortality per
                  10 ug/m3 increase in PM25from recent multicity studies.	6-183
Figure 6-28.        Percent increase in all-cause (nonaccidental) and cause-specific mortality per 10 ug/m3
                  increase in the average of 0- and 1-day lagged PM10.2.5, combined by climatic regions.	6-186
Figure 6-29.       Empirical Bayes-adjusted city-specific percent increase in total (nonaccidental),
                  cardiovascular, and respiratory mortality per 10 ug/m3 increase in the average of 0- and 1-
                  day lagged PM10.2.5 by decreasing 98th percentile of mean 24-h avg PM10.2.5 concentrations.	6-187
Figure 6-30.       Summary of percent increase in total (nonaccidental) and cause-specific mortality per
                  10 ug/m3 increase in PM10.2.5 for all U.S.-, Canadian-, and international-based studies.	6-190
Figure 6-31.       Percent increase in PM10 risk estimates (point estimates and 95% CIs) associated with a
                  5th-95th percentile increase in PM25 and PM25 chemical  components.	6-192
Figure 6-32.       Sensitivity of the percent increase in PM10 risk estimates  (point estimates and 95% CIs)
                  associated with an interquartile increase in Ni.	6-193
Figure 6-33.       Percent excess risk (Cl) of total (nonaccidental) mortality per IQR of concentrations.	6-196
Figure 6-34.       Relative risk and Cl of cardiovascular mortality associated with estimated PM25 source
                  contributions.	6-197
Figure 6-35.       Concentration-response curves (spline model) for all-cause, cardiovascular, respiratory and
                  other cause mortality from the 20 NMMAPS cities.	6-198
Figure 6-36.       Percent increase in the risk of death on days with PM10 concentrations in the ranges of
                  15-24, 25-34, 35-44, and 45 ug/m3 and greater, compared to a reference of days when
                  concentrations were below 15 ug/m3.	6-199
Figure 6-37.       Combined concentration-response curves (spline model) for all-cause, cardiovascular, and
                  respiratory mortality from the 22 APHEA cities.	6-200
Figure 7-1.         Risk estimates for the associations of clinical outcomes with long-term exposure to ambient
                  PM2.5and  PM10.	7-15
Figure 7-2.         Adjusted ORs and 95% CIs of symptoms and respiratory diseases associated with a
                  decline of  10 ug/m3 PM10 levels in Swiss Surveillance  Program of Childhood Allergy and
                  Respiratory Symptoms.	7-23
Figure 7-3.         Effect of PM2 5 on the association of lung function with asthma.	7-24
Figure 7-4.         Proportion of 18-yr olds with an FE\A below 80% of the predicted value plotted against the
                  average levels of pollutants from 1994 through 2000 in the 12 southern California
                  communities of the Children's Health Study.	7-28
December 2009                                           xxviii

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Figure 7-5.         Percent increase in postneonatal mortality per 10 ug/m3 in PM10, comparing risk for total
                  and respiratory mortality.	7-58

Figure 7-6.         Mortality risk estimates associated with long-term exposure to PM25 from the Harvard Six
                  Cities Study (SCS) and the American Cancer Society Study (ACS).	7-85

Figure 7-7.         Mortality risk estimates, long-term exposure to PM25 in recent cohort studies.	7-86

Figure 7-8.         Plots of the relative risk of death from cardiovascular disease from the Women's Health
                  Initiative study displaying the between-city and within-city contributions to the overall
                  association between PM25 and cardiovascular mortality windows of exposure-effects.	7-92

Figure 7-9.         The model-averaged estimated effect of a 10-ug/m3 increase in PM2 5 on all-cause mortality
                  at different lags (in years) between exposure and death.	7-93

Figure 7-10.       Time course of relative risk of death after  a sudden decrease in air pollution exposure
                  during the year 2000, assuming a steady  state model (solid line) and a dynamic model
                  (bold dashed  line).	7-94

Figure 7-11.       Experts' mean effect estimates and  uncertainty distributions for the PM2 5 mortality
                  concentration-response coefficient for a 1  ug/m3 change in annual average PM25.	7-96

Figure 9-1.         Important factors involved in seeing a scenic vista are outlined.	9-3

Figure 9-2.         Schematic of remote-area (top) and urban (bottom) nighttime sky visibility showing the
                  effects of PM  and light pollution.	9-4

Figure 9-3.         Effect of relative humidity on light scattering by mixtures of ammonium  nitrate and
                  ammonium sulfate.	9-6

Figure 9-4.         Estimated fractions of total particulate nitrate during each field campaign comprised of
                  ammonium nitrate, reacted sea salt  nitrate (shown as NaN03), and reacted soil dust nitrate
                  (shown  as Ca(N03)2).	9-12

Figure 9-5.         A scatter plot  of the original IMPROVE algorithm estimated  particle light scattering versus
                  measured particle light scattering.	9-15

Figure 9-6.         Scatter  plot of the revised algorithm estimates of light scattering versus measured light
                  scattering.	9-15

Figure 9-7.         IMPROVE network PM species estimated light extinction for 2000 (left) and for 2004 (right).	9-18

Figure 9-8.         Mean estimated light extinction from PM speciation measurements for the first  (top left),
                  second  (top right), third (bottom left), and  fourth (bottom right) calendar quarters of 2004.	9-18

Figure 9-9.         Percent contributions of ammonium nitrate (left column) and ammonium sulfate (right
                  column) to particulate light extinction for each calendar quarter of 2004 (first through fourth
                  quarter  arranged from top to bottom).	9-20

Figure 9-10.       Percent contributions of organic mass (left column) and EC (right column) to particulate
                  light extinction for each calendar quarter of 2004 (first through fourth quarter arranged from
                  top to bottom).	9-21

Figure 9-11.       Percent contributions of coarse mass (left column) and fine  soil (right column) to particulate
                  light extinction for each calendar quarter of 2004 (first through fourth quarter arranged from
                  top to bottom).	9-22

Figure 9-12.       IMPROVE Mean PM25 mass concentration determined by summing the major components
                  for the 2000-2004.	9-24

Figure 9-13.       IMPROVE and CSN (STN) mean PM25 mass concentration determined by summing the
                  major components for 2000-2004.	9-24

Figure 9-14.       IMPROVE mean ammonium nitrate  concentrations for 2000-2004.	9-25
December 2009                                           xxix

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Figure 9-1 5.
Figure 9-1 6.
Figure 9-1 7.
Figure 9-1 8.
Figure 9-1 9.
Figure 9-20.
Figure 9-21.
Figure 9-22.
Figure 9-23.
Figure 9-24.
Figure 9-25.
Figure 9-26.
Figure 9-27.
Figure 9-28.
Figure 9-29.
Figure 9-30.
Figure 9-31.
Figure 9-32.
Figure 9-33.
IMPROVE and CSN (STN) mean ammonium nitrate concentrations for 2000-2004.
IMPROVE mean ammonium sulfate concentrations for 2000-2004.
IMPROVE and CSN (STN) mean ammonium sulfate concentrations for 2000-2004.
IMPROVE monitored mean orqanic mass concentrations for 2000-2004.
IMPROVE and CSN (STN) mean orqanic mass concentrations for 2000-2004.
IMPROVE mean EC concentrations for 2000-2004.
IMPROVE and CSN (STN) mean EC concentrations for 2000-2004.
IMPROVE mean fine soil concentrations for 2000-2004.
IMPROVE and CSN (STN) fine soil concentrations, 2000-2004.
Regional and local contributions to annual average PM2 5 by particulate S042", nitrate and
total carbon (i.e., organic plus EC) for select urban areas based on paired IMPROVE and
CSN monitorinq sites.
IMPROVE mean coarse mass concentrations for 2000-2004.
Ten-year (1995-2004) haze trends for the mean of the 20% best annual haze conditions.
Ten-year (1995-2004) haze trends for the mean of the 20% worst annual haze conditions.
Ten-year trends in the 80th percentile particulate S042" concentration based on IMPROVE
and CASTNet monitoring and net S02 emissions from the National Emissions Trends
(NET) data base by reqion of the U.S.
Map of 1 0-yr trends (1 994-2003) in haze by particulate nitrate contribution to haze for the
worst 20% annual haze periods.
Contributions of the Pacific Coast area to the ammonium sulfate (ug/m3) at 84 remote-area
monitoring sites in western U.S. based on trajectory regression for all sample periods from
2000-2002
Shows the IMPROVE monitoring sites in the WRAP region with at least three years of valid
data and identifies the six sites selected to demonstrate the apportionment tools.
Particulate S042" (a) and nitrate (b) source attribution by region using CAMx modeling for
six western remote area monitorinq sites
Monthly averaged model predicted organic mass concentration apportioned into primary
PM and anthropogenic and biogenic secondary PM categories for the Olympic NP (top)
and San Gorqonio W (bottom) monitorinq sites.
9-25
9-26
9-26
9-28
9-28
9-29
9-29
9-30
9-30
9-32
9-33
9-34
9-35
9-36
9-37
9-39
9-41
9-43
9-44
Figure 9-34.        Monthly averaged model predicted organic mass concentration apportioned into primary
                  PM and anthropogenic and biogenic secondary PM categories for the Yellowstone NP (top)
                  and Grand Canyon (Hopi Point) (bottom) monitoring sites.	9-45

Figure 9-35.        Monthly averaged model predicted organic mass concentration apportioned into primary
                  PM and anthropogenic and biogenic secondary PM categories for the Badland NP (top)
                  and Salt Creek W (bottom) monitoring sites.	9-46

Figure 9-36.        Comparison of carbon concentrations between Seattle (Puget Sound site) and Mt. Rainer
                  (left) and between Phoenix and Tonto (right) showing the background site concentration
                  (gray) and the urban excess concentration (black) for total, fossil and contemporary carbon
                  during the summer and winter studies.	9-47

Figure 9-37.        Average contemporary fraction of PM2.s carbon for the summer (top) and winter (bottom),
                  estimated from IMPROVE monitoring data (June 2004-February 2006) based on  EC/TC
                  ratios.	9-48
December 2009                                           xxx

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Figure 9-38.        Results of the weighted emissions potential tool applied to primary OC emissions (top) and
                  EC emissions (bottom) for the baseline and projected 2018 emissions inventories for
                  Olympic NP.	9-50

Figure 9-39.        Results of the weighted emissions potential tool applied to primary OC emissions (top) and
                  EC emissions (bottom) for the baseline and projected 2018 emissions inventories for San
                  Gorgonio W.	9-51

Figure 9-40.        Results of the weighted emissions potential tool applied to primary OC emissions (top) and
                  EC emissions (bottom) for the baseline and projected 2018 emissions inventories for
                  Yellowstone NP.	9-53

Figure 9-41.        Results of the weighted emissions potential tool applied to primary OC emissions (top) and
                  EC emissions (bottom) for the baseline and projected 2018 emissions inventories for Grand
                  Canyon  NP.	9-54

Figure 9-42.        Results of the weighted emissions potential tool applied to primary OC emissions (top) and
                  EC emissions (bottom) for the baseline and projected 2018 emissions inventories for
                  Badlands NP.	9-55

Figure 9-43.        Results of the weighted emissions potential tool applied to primary OC emissions (top) and
                  EC emissions (bottom) for the baseline and projected 2018 emissions inventories for Salt
                  Creek W.	9-56

Figure 9-44.        BRAVO  study haze contributions for Big Bend NP, TX during a 4-mo period in 1999.	9-58

Figure 9-45.        Maps of spatial patterns for average annual particulate nitrate measurements (top), and for
                  ammonia emissions for April 2002 from the WRAP emissions inventory (bottom).	9-59

Figure 9-46.        Maps of spatial patterns of annual NO (left) and N02 (right) emissions for 2002 from the
                  WRAP emissions inventory.	9-60

Figure 9-47.        Midwest ammonia monitoring network.	9-61

Figure 9-48.        Upwind transport probability fields associated with high particulate nitrate concentrations
                  measured at Toronto, Canada; Boundary Water Canoe Area, MN; Shenandoah NP, VA;
                  Lye Brook, VT; and Great Smoky Mountains NP, TN.	9-62

Figure 9-49.        Trajectory probability fields for periods with high particulate S042" measured at Underbill,
                  VT and Brigantine, NJ (shown as white stars) associated with oil-burning trace components
                  (left) and with coal-burning trace components (right).	9-63

Figure 9-50.        Scatter plots of particulate S042" (left) and particulate S042" and organic mass (right)
                  versus nephelometer measured particle light scattering for Acadia NP, ME.	9-64

Figure 9-51.        CMAQ air quality modeling projections of visibility responses on the  20% worst haze days
                  at  Great Smoky Mountains NP, NC (top) and Swanquarter W, NC (bottom) to 30%
                  reductions.	9-65

Figure 9-52.        Aerosol radiative forcing.	9-76

Figure 9-53.        Global average radiative forcing (RF) estimates and uncertainty ranges in 2005, relative to
                  the pre-industrial climate.	9-78

Figure 9-54.        Probability distribution functions (PDFs) for anthropogenic aerosol and GHG RFs.	9-79

Figure 9-55.        The clear-sky forcing efficiency ET, defined as the diurnally averaged aerosol direct
                  radiative effect (W/m2) per unit AOD at 550 nm,  calculated at both TOA and the surface, for
                  typical aerosol types over different geographical regions.	9-80

Figure 9-56.        A composite of MODIS/Terra observed aerosol optical depth (at 550 nm, green light near
                  the peak of human vision) and fine-mode fraction that shows spatial  and seasonal
                  variations of aerosol types.	9-87
December 2009                                            xxxi

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Figure 9-57.        Oregon fire on September 4, 2003, as observed by MISR: (a) MISR nadir view of the fire
                  plume, with five patch locations numbered and wind-vectors superposed in yellow; (b)
                  MISR aerosol optical depth at 558 nm; and (c) MISR stereo height without wind correction
                  for the same region.	9-88

Figure 9-58.        Global maps at 18 km resolution showing monthly average (a) AOD at 865 nm and (b)
                  Angstrom exponent of AOD over water surfaces only for June, 1997, derived from radiance
                  measurements by the POLDER.	9-89

Figure 9-59.        A dust event that originated in the Sahara desert on 17 August 2007 and was transported
                  to the Gulf of Mexico.	9-91

Figure 9-60.        A constellation of five spacecraft that overfly the Equatorat about 1:30 p.m., the so-called
                  A-Train, carries sensors having complementary capabilities, offering unprecedented
                  opportunities to study aerosols from space in multiple dimensions.	9-92

Figure 9-61.        Geographical coverage of active AERONET sites in 2006.	9-95

Figure 9-62.        Comparison of the mean concentration (ug/m3) and standard deviation of the modeled
                  (STEM) aerosol chemical components with shipboard measurements during INDOEX,
                  ACE-Asia, and  ICARTT.	9-98

Figure 9-63.        Correlations between one-hour PMu surface measurements in the U.S. and southern
                  Canada reported to AIRNOW and MODIS satellite AOD values for the period between 4
                  July and 1 September 2009.	9-99

Figure 9-64.        Location of aerosol chemical composition measurements with aerosol mass spectrometers.	9-101

Figure 9-65.        Scatterplots of the submicrometer POM measured during  NEAQS versus A) acetylene and
                  B) iso-propyl nitrate.	9-102

Figure 9-66.        Comparison of annual mean aerosol optical depth (AOD).	9-104

Figure 9-67.        Percentage contributions of individual aerosol components.	9-105

Figure 9-68.        Geographical patterns of seasonally (MAM) averaged aerosol optical depth at 550 nm (left
                  panel) and the diurnally averaged clear-sky aerosol direct radiative (solar spectrum) forcing
                  (W/m2) at the TOA (right panel) derived from satellite (Terra) retrievals.	9-107

Figure 9-69.        Summary of observation- and model-based (denoted as OBS and MOD, respectively)
                  estimates of clear-sky, annual average DRF at the TOA and at the surface.	9-108

Figure 9-70.        Scatter plots showing mean cloud drop effective radius (re) versus aerosol extinction
                  coefficient (unit: km-1) for various liquid water path (LWP) bands on April 3,1998 at ARM
                  SGPsite.	9-115

Figure 9-71.        Sampling the Arctic Haze. Pollution and smoke aerosols can travel long distances, from
                  mid-latitudes to the Arctic, causing "Arctic Haze."	9-123

Figure 9-72.        Global annual averaged AOD (upper panel) and aerosol mass loading (lower panel) with
                  their components simulated by 15 models in AeroCom- A  (excluding one model which only
                  reported mass).	9-130

Figure 9-73.        Aerosol direct radiative  forcing in various climate and aerosol models.	9-134

Figure 9-74.        Aerosol optical thickness and anthropogenic shortwave  all-sky radiative forcing from the
                  AeroCom study.	9-135

Figure 9-75.        Radiative forcing from the cloud albedo effect (1st aerosol indirect effect) in the global
                  climate models used from IPCC (2007, 092765),  Chapter 2, Figure 2.14, of the IPCC AR4.	9-136
December 2009                                           xxxii

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Figure 9-76.       Anthropogenic impact on cloud cover, planetary albedo, radiative flux at the surface (while
                  holding sea surface temperatures and sea ice fixed) and surface air temperature change
                  from the direct aerosol forcing (top row), the first indirect effect (second row) and the
                  second indirect effect (third row).	9-139

Figure 9-77.       Global average present-day short wave cloud forcing at TOA (top) and change in whole sky
                  net outgoing shortwave radiation (bottom) between the present-day and pre-industrial
                  simulations for each model in each experiment.	9-140
Figure 9-78.
Figure 9-79.
Figure 9-80.
Figure 9-81.
Figure 9-82.
Figure 9-83.
Figure 9-84.
Figure 9-85.
Figure A-1 .
Figure A-2.
Figure A-3.
Figure A-4.
Figure A-5.
Figure A-6.
Figure A-7.
Figure A-8.
Figure A-9.
Figure A-1 0.
Figure A-1 1.
Figure A-1 2.
Figure A-1 3.
Figure A-1 4.
Figure A-1 5.
Figure A-1 6.
Figure A-1 7.
Figure A-1 8.
Direct radiative forcing by anthropogenic aerosols in the GISS model (including sulfates,
BC, OC and nitrates).
Percentage of aerosol optical depth in the GISS, left, based on Liu et al. (2006, 190422),
provided by A. Lads, GISS, and GFDL, riqht, from Ginoux et al. (2006, 190582).
Most probable aerosol altitude (in pressure, hPa) from the GISS model in January (top) and
July (bottom).
Time dependence of aerosol optical thickness (left) and climate forcing (right). Note that as
specified, the aerosol trends are all "flat" from 1990-2000.
Change in global mean ocean temperature (left axis) and ocean heat content (right axis) for
the top 3000 m due to different forcinqs in the GFDL model.
Visible (wavelength 0.55 urn) optical depth estimates of stratospheric S042" aerosols
formed in the aftermath of explosive volcanic eruptions that occurred between 1860 and
2000.
The transfer of POPs between the maior abiotic compartments of the Arctic.
Relationship of plant nutrients and trace metals with veqetation.
PM?^ monitor distribution in comparison with population density, Atlanta, GA.
PMm monitor distribution in comparison with population density, Atlanta, GA.
PM?^ monitor distribution in comparison with population density, Birminqham, AL.
PMm monitor distribution in comparison with population density, Birminqham, AL.
PM^ monitor distribution in comparison with population density, Boston, MA.
PMm monitor distribution in comparison with population density, Boston, MA.
PM?<; monitor distribution in comparison with population density, Chicaqo, IL.
PMm monitor distribution in comparison with population density, Chicaqo, IL.
PM?<; monitor distribution in comparison with population density, Denver, CO.
PMm monitor distribution in comparison with population density, Denver, CO.
PM?<; monitor distribution in comparison with population density, Detroit, Ml.
PMm monitor distribution in comparison with population density, Detroit, Ml.
PM?<; monitor distribution in comparison with population density, Houston, TX.
PMm monitor distribution in comparison with population density, Houston, TX.
PM?<; monitor distribution in comparison with population density, Los Anqeles, CA.
PMm monitor distribution in comparison with population density, Los Anqeles, CA.
PM? i monitor distribution in comparison with population density, New York, NY.
PMm monitor distribution in comparison with population density, New York, NY.
9-148
9-151
9-153
9-155
9-156
9-163
9-169
9-185
A-59
A-60
A-61
A-62
A-63
A-64
A-65
A-66
A-67
A-68
A-69
A-70
A-71
A-72
A-73
A-74
A-75
A-76
December 2009                                           xxxiii

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Figure A-1 9.
Figure A-20.
Figure A-21.
Figure A-22.
Figure A-23.
Figure A-24.
Figure A-25.
Figure A-26.
Figure A-27.
Figure A-28.
Figure A-29.
Figure A-30.
Figure A-31.
Figure A-32.
Figure A-33.
Figure A-34.
Figure A-35.
Figure A-36.
Figure A-37.
Figure A-38.
Figure A-39.
Figure A-40.
Figure A-41 .
Figure A-42.
Figure A-43.
Figure A-44.
Figure A-45.
Figure A-46.
Figure A-47.
PM^ monitor distribution in comparison with population density, Philadelphia, PA.
PMm monitor distribution in comparison with population density, Philadelphia, PA.
PM?^ monitor distribution in comparison with population density, Phoenix, AZ.
PMm monitor distribution in comparison with population density, Phoenix, AZ.
PM?^ monitor distribution in comparison with population density, Pittsburgh, PA.
PMm monitor distribution in comparison with population density, Pittsburgh, PA.
PM?^ monitor distribution in comparison with population density, Riverside, CA.
PMm monitor distribution in comparison with population density, Riverside, CA.
PM?<; monitor distribution in comparison with population density, Seattle, WA.
PMm monitor distribution in comparison with population density, Seattle, WA.
PM?<; monitor distribution in comparison with population density, St. Louis, MO.
PMm monitor distribution in comparison with population density, St. Louis, MO.
Three-yravg of 24-h PM25 Cu concentrations measured at CSN sites across the U.S.,
2005-2007.
Three-yr avg of 24-h PM25 Fe concentrations measured at CSN sites across the U.S.,
2005-2007
Three-yr avg of 24-h PM25 Ni concentrations measured at CSN sites across the U.S.,
2005-2007
Three-yr avg of 24-h PM25 Pb concentrations measured at CSN sites across the U.S.,
2005-2007
Three-yravg of 24-h PM25 Se concentrations measured at CSN sites across the U.S.,
2005-2007
Three-yr avg of 24-h PM25 V concentrations measured at CSN sites across the U.S., 2005-
2007
PM?<; monitor distribution and maior highways, Atlanta, GA.
Box plots illustrating the seasonal distribution of 24-h avg PM25 concentrations for Atlanta,
GA.
PM?<; inter-sampler correlations as a function of distance between monitors for Atlanta, GA.
PM?<; monitor distribution and maior highways, Birmingham, AL.
Box plots illustrating the seasonal distribution of 24-h avg PM25 concentrations for
Birmingham, AL.
PM25 inter-sampler correlations as a function of distance between monitors for
Birmingham, AL.
PM?<; monitor distribution and maior highways, Boston, MA.
Box plots illustrating the seasonal distribution of 24-h avg PM25 concentrations for Boston,
MA.
PM?<; inter-sampler correlations as a function of distance between monitors for Boston, MA.
PM?<; monitor distribution and maior highways, Chicago, IL.
Box plots illustrating the seasonal distribution of 24-h avg PM25 concentrations for Chicago,
IL.
A-77
A-78
A-79
A-80
A-81
A-82
A-83
A-84
A-85
A-86
A-87
A-88
A-89
A-90
A-91
A-92
A-93
A-94
A-96
A-97
A-99
A-1 00
A-1 01
A-1 03
A-1 04
A-1 05
A-1 07
A-1 08
A-1 10
December 2009                                        xxxiv

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Figure A-48.       PM2 5 inter-sampler correlations as a function of distance between monitors for Chicago, IL.	A-113
Figure A-49.       PM2.5 monitor distribution and major highways, Denver, CO.	A-114
Figure A-50.       Box plots illustrating the seasonal distribution of 24-h avg PM2 5 concentrations for Denver,
                  CO.	A-115
Figure A-51.       PM2.5 inter-sampler correlations as a function of distance between monitors for Denver, CO.	A-117
Figure A-52.       PM25 monitor distribution and major highways, Detroit, Ml.	A-118
Figure A-53.       Box plots illustrating the seasonal distribution of 24-h avg PM2 5 concentrations for Detroit,
                  Ml.	A-119
Figure A-54.       PM25 inter-sampler correlations as a function of distance between monitors for Detroit, Ml.	A-121
Figure A-55.       PM25 monitor distribution and major highways, Houston, TX.	A-122
Figure A-56.       Box plots illustrating the seasonal distribution of 24-h avg PM25 concentrations for Houston,
                  TX.	A-123
Figure A-57.       PM2 5 inter-sampler correlations as a function of distance between monitors for Houston,
                  TX.	A-124
Figure A-58.       PM2 5 monitor distribution and major highways, Los Angeles, CA.	A-125
Figure A-59.       Box plots illustrating the seasonal distribution of 24-h avg PM2 5 concentrations for Los
                  Angeles, CA.	A-126
Figure A-60.       PM2 5 inter-sampler correlations as a function of distance between monitors for Los
                  Angeles, CA.	A-127
Figure A-61.       PM2 5 monitor distribution and major highways, New York City, NY.	A-128
Figure A-62.       Box plots illustrating the seasonal distribution of 24-h avg PM2 5 concentrations for New
                  York, NY.	A-130
Figure A-63       PM2 5 inter-sampler correlations as a function of distance between monitors for New York,
                  NY.	A-133
Figure A-64.       PM2 5 monitor distribution and major highways, Philadelphia, PA.	A-134
Figure A-65.       Box plots illustrating the seasonal distribution of 24-h avg PM2 5 concentrations for
                  Philadelphia, PA.	A-135
Figure A-66.       PM2 5 inter-sampler correlations as a function of distance between monitors for
                  Philadelphia, PA.	A-137
Figure A-67.       PM25 monitor distribution and major highways, Phoenix, AZ.	A-138
Figure A-68.       Box plots illustrating the seasonal distribution of 24-h avg PM2 5 concentrations for Phoenix,
                  AZ.	A-139
Figure A-69.       PM2 5 inter-sampler correlations as a function of distance between monitors for Phoenix,
                  AZ.	A-141
Figure A-70.       PM25 monitor distribution and major highways, Pittsburgh, PA.	A-142
Figure A-71.       Box plots illustrating the seasonal distribution of 24-h avg PM2 5 concentrations for
                  Pitsburgh, PA.	A-143
Figure A-72.       PM2 5 inter-sampler correlations as a function of distance between monitors for Pittsburgh,
                  PA.	A-145
Figure A-73.       PM25 monitor distribution and major highways, Riverside, CA.	A-146
December 2009                                            xxxv

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Figure A-74.        Box plots illustrating the seasonal distribution of 24-h avg PM2 5 concentrations for
Figure A-75.
Figure A-76.
Figure A-77.
Figure A-78.
Figure A-79.
Figure A-80.
Figure A-81
Figure A-82.
Figure A-83.
Figure A-84.
Figure A-85.
Figure A-86.
Figure A-87
Figure A-88.
Figure A-89.
Figure A-90
Figure A-91.
Figure A-92.
Figure A-93.
Figure A-94.
Figure A-95.
Figure A-96.
Figure A-97.
Figure A-98.
Figure A-99.
Figure A-1 00.
Riverside, CA.
PM2 5 inter-sampler correlations as a function of distance between monitors for Riverside
CA.
PM?^ monitor distribution and maior highways, Seattle, WA.
Box plots illustrating the seasonal distribution of 24-h avg PM25 concentrations for Seattle,
WA.
PM?^ inter-sampler correlations as a function of distance between monitors for Seattle, WA.
PM?<; monitor distribution and maior highways, St. Louis, MO.
Box plots illustrating the seasonal distribution of 24-h avg PM25 concentrations for St.
Louis, MO.
PM2 5 inter-sampler correlations as a function of distance between monitors for St. Louis,
MO.
PMm monitor distribution and maior highways, Atlanta, GA.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Atlanta,
GA.
PMm inter-sampler correlations as a function of distance between monitors for Atlanta, GA.
PMm monitor distribution and maior highways, Birmingham, AL.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for
Birmingham, AL.
PM10 inter-sampler correlations as a function of distance between monitors for Birmingham,
AL.
PMm monitor distribution and maior highways, Boston, MA.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Boston,
MA.
PMm inter-sampler correlations as a function of distance between monitors for Boston, MA.
PMm monitor distribution and maior highways, Chicago, IL.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Chicago,
IL.
PMm inter-sampler correlations as a function of distance between monitors for Chicago, IL.
PMm monitor distribution and maior highways, Denver, CO.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Denver,
CO.
PMm inter-sampler correlations as a function of distance between monitors for Denver, CO.
PMm monitor distribution and maior highways, Detroit, Ml.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Detroit,
Ml.
PMm inter-sampler correlations as a function of distance between monitors for Detroit, Ml.
PMm monitor distribution and maior highways, Houston, TX.
A-1 47
A-1 49
A-1 50
A-1 51
A-1 52
A-1 53
A-1 54
A-1 56
A-1 57
A-1 58
A-1 60
A-1 61
A-1 62
A-1 64
A-1 65
A-1 66
A-1 67
A-1 68
A-1 69
A-1 71
A-1 72
A-1 73
A-1 75
A-1 76
A-1 77
A-1 78
A-1 79
December 2009                                            xxxvi

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Figure A-101.       Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Houston,
Figure A-1 02.
Figure A-1 03.
Figure A-1 04.
Figure A-1 05.
Figure A-1 06.
Figure A-1 07.
Figure A-1 08.
Figure A-1 09.
Figure A-1 10.
Figure A-1 11.
Figure A-1 12.
Figure A-1 13.
Figure A-1 14.
Figure A-1 15.
Figure A-1 16.
Figure A-1 17.
Figure A-1 18.
Figure A-1 19.
Figure A-1 20.
Figure A-1 21.
Figure A-1 22.
Figure A-1 23.
Figure A-1 24.
Figure A-1 25.
Figure A-1 26.
TX.
PMio inter-sampler correlations as a function of distance between monitors for Houston, TX.
PMm monitor distribution and maior highways, Los Anqeles, CA.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Los
Anqeles, CA.
PMio inter-sampler correlations as a function of distance between monitors for Los Angeles,
CA.
PMm monitor distribution and maior highways, New York, NY.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for New
York, NY.
PM10 inter-sampler correlations as a function of distance between monitors for New York,
NY.
PMm monitor distribution and maior highways, Philadelphia, PA.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for
Philadelphia, PA.
PM10 inter-sampler correlations as a function of distance between monitors for Philadelphia,
PA.
PMm monitor distribution and maior highways, Phoenix, AZ.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Phoenix,
AZ.
PMm inter-sampler correlations as a function of distance between monitors for Phoenix, AZ.
PMm monitor distribution and maior highways, Pittsburgh, PA.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for
Pittsburgh, PA.
PM10 inter-sampler correlations as a function of distance between monitors for Pittsburgh,
PA.
PMm monitor distribution and maior highways, Riverside, CA.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for
Riverside, CA.
PM10 inter-sampler correlations as a function of distance between monitors for Riverside,
CA.
PMm monitor distribution and maior highways, Seattle, WA.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for Seattle,
WA.
PMm inter-sampler correlations as a function of distance between monitors for Seattle, WA.
PMm monitor distribution and maior highways, St. Louis, MO.
Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations for St. Louis,
MO.
PM10 inter-sampler correlations as a function of distance between monitors for St. Louis,
MO.
A-1 80
A-1 82
A-1 83
A-1 84
A-1 85
A-1 86
A-1 87
A-1 88
A-1 89
A-1 90
A-1 91
A-1 92
A-1 94
A-1 97
A-1 98
A-1 99
A-201
A-202
A-203
A-205
A-206
A-207
A-208
A-209
A-210
A-212
December 2009                                            xxxvii

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Figure A-127.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Atlanta, GA.	A-213

Figure A-128.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Birmingham, AL.	A-214

Figure A-129.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Boston, MA.	A-215

Figure A-130.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Chicago, IL.	A-216

Figure A-131.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter, derived using the SANDWICH method in Denver, CO.	A-217

Figure A-132.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Detroit, Ml.	A-218

Figure A-133.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Houston, TX.	A-219

Figure A-134.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Los Angeles, CA.	A-220

Figure A-135.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in New York, NY.	A-221

Figure A-136.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Philadelphia, PA.	A-222

Figure A-137.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Phoenix, AZ.	A-223

Figure A-138.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Pittsburgh, PA.	A-224

Figure A-139.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Riverside, CA.	A-225

Figure A-140.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in Seattle, WA.	A-226

Figure A-141.      Seasonally averaged PM2 5 speciation data for 2005-2007 for a) annual, b) spring,
                 c) summer, d) fall and e) winter derived using the SANDWICH method in St. Louis, MO.	A-227

Figure A-142.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                 Atlanta, GA, 2005-2007.	A-228

Figure A-143.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                 Birmingham, AL, 2005-2007.	A-228

Figure A-144.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                 Boston, MA, 2005-2007.	A-229

Figure A-145.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                 Chicago, IL, 2005-2007.	A-229

Figure A-146.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                 Denver, CO, 2005-2007.	A-230

Figure A-147.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                 Detroit, Ml, 2005-2007.	A-230
December 2009                                         xxxviii

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Figure A-148.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  Houston, TX, 2005-2007.	A-231

Figure A-149.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  Los Angeles, CA, 2005-2007.	A-231

Figure A-150.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  New York, NY, 2005-2007.	A-232

Figure A-151.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  Philadelphia, PA, 2005-2007.	A-232

Figure A-152.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  Phoenix, AZ, 2005-2007.	A-233

Figure A-153.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  Pittsburgh, PA, 2005-2007.	A-233

Figure A-154.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  Riverside, CA, 2005-2007.	A-234

Figure A-155.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  Seattle, WA, 2005-2007.	A-234

Figure A-156.      Seasonal patterns in PM2 5 chemical composition from city-wide monthly average values for
                  St. Louis, MO, 2005-2007.	A-235

Figure A-157.      Diel plots generated from all available hourly FRM-like PM25 data, stratified by weekday
                  (left) and weekend (right), in Atlanta, GA.	A-235

Figure A-158.      Diel plots generated from all available hourly FRM-like PM25 data, stratified by weekday
                  (left) and weekend (right), in Chicago, IL.	A-236

Figure A-159.      Diel plots generated from all available hourly FRM-like PM25 data, stratified by weekday
                  (left) and weekend (right), in Houston, TX.	A-236

Figure A-160.      Diel plots generated from all available hourly FRM-like PM25 data, stratified by weekday
                  (left) and weekend (right), in New York, NY.	A-237

Figure A-161.      Diel plots generated from all available hourly FRM-like PM25 data, stratified by weekday
                  (left) and weekend (right), in Pittsburgh, PA.	A-237

Figure A-162.      Diel plots generated from all available hourly FRM-like PM25 data, stratified by weekday
                  (left) and weekend (right), in Seattle, WA.	A-238

Figure A-163.      Diel plots generated from all available hourly FRM-like PM25 data, stratified by weekday
                  (left) and weekend (right), in St. Louis, MO.	A-238

Figure A-164.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Atlanta, GA.	A-239

Figure A-165.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Chicago, IL.	A-239

Figure A-166.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Denver, CO.	A-240

Figure A-167.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Detroit, Ml.	A-240

Figure A-168.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Los Angeles, CA.	A-241
December 2009                                            xxxix

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Figure A-169.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Philadelphia, PA.	A-241

Figure A-170.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Phoenix, AZ.	A-242

Figure A-171.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Pittsburgh, PA.	A-242

Figure A-172.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Riverside, CA.	A-243

Figure A-173.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in Seattle, WA.	A-243

Figure A-174.      Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by weekday
                  (left) and weekend (right), in St. Louis, MO.	A-244

Figure A-175.      Correlations between 24-h PM2 5 and co-located 24-h avg PM10, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Atlanta, GA, stratified by season (2005-2007).	A-245

Figure A-176.      Correlations between 24-h PM2.5 and co-located 24-h avg PM10, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Birmingham, AL, stratified by season (2005-2007).	A-246

Figure A-177.      Correlations between 24-h PM2 5 and co-located 24-h avg PM10, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Boston, MA, stratified by season (2005-2007).	A-247

Figure A-178.      Correlations between 24-h PM2.5 and co-located 24-h avg PM10, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Chicago, IL, stratified by season (2005-2007).	A-248

Figure A-179.      Correlations between 24-h PM2 5 and co-located 24-h avg PM10, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03for Denver, CO, stratified by season (2005-2007).	A-249

Figure A-180.      Correlations between 24-h PM2.5 and co-located 24-h avg PM10, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03for Detroit, Ml, stratified by season (2005-2007).	A-250

Figure A-181.      Correlations between 24-h PM2 5 and co-located 24-h avg PM10, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Houston, TX, stratified by season (2005-2007).	A-251

Figure A-182.      Correlations between 24-h PM2.5 and co-located 24-h avg PM10, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Los Angeles, CA, stratified by season (2005-2007).	A-252

Figure A-183.      Correlations between 24-h PM2.5 and co-located 24-h avg PM10, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03for New York,  NY, stratified by season (2005-2007).	A-253

Figure A-184.      Correlations between 24-h PM2.5 and co-located 24-h avg PM10, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Philadelphia, PA, stratified by season (2005-2007).	A-254

Figure A-185.      Correlations between 24-h PM2 5 and co-located 24-h avg PM10, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Phoenix, AZ, stratified by season (2005-2007).	A-255

Figure A-186.      Correlations between 24-h PM2.5 and co-located 24-h avg PM10, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Pittsburgh, PA, stratified by season (2005-2007).	A-256

Figure A-187.      Correlations between 24-h PM2 5 and co-located 24-h avg PM10, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Riverside,  CA, stratified by season (2005-2007).	A-257

Figure A-188.      Correlations between 24-h PM2.5 and co-located 24-h avg PM10, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for St. Louis, MO, stratified by season (2005-2007).	A-258

Figure A-189.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Atlanta, GA, stratified by season (2005-2007).	A-259
December 2009

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Figure A-190.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Birmingham, AL, stratified by season (2005-2007).	A-260

Figure A-191.      Correlations between 24-h PM10 and co-located 24-h avg PM2 5, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Boston, MA, stratified by season (2005-2007).	A-261

Figure A-192.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Chicago, IL, stratified by season (2005-2007).	A-262

Figure A-193.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Denver, CO, stratified by season (2005-2007).	A-263

Figure A-194.      Correlations between 24-h PM10 and co-located 24-h avg PM2 5, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Detroit, Ml, stratified by season (2005-2007).	A-264

Figure A-195.      Correlations between 24-h PM10 and co-located 24-h avg PM2 5, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Houston, TX, stratified by season (2005-2007).	A-265

Figure A-196.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Los Angeles, CA, stratified by season (2005-2007).	A-266

Figure A-197.      Correlations between 24-h PM10 and co-located 24-h avg PM2 5, PM10.2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for New York, NY, stratified by season (2005-2007).	A-267

Figure A-198.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Philadelphia, PA, stratified by season (2005-2007).	A-268

Figure A-199.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Phoenix, AZ, stratified by season (2005-2007).	A-269

Figure A-200.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Pittsburgh, PA, stratified by season (2005-2007).	A-270

Figure A-201.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for Riverside, CA, stratified by season (2005-2007).	A-271

Figure A-202.      Correlations between 24-h PM10 and co-located 24-h avg PM2.5, PM10-2.5, S02, N02 and CO
                  and daily maximum 8-h avg 03 for St. Louis, MO, stratified by season (2005-2007).	A-272
December 2009                                           xli

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                       PM  ISA  Project Team
Executive Direction

Dr. John Vandenberg (Director)—National Center for Environmental Assessment-RTF Division, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Ms. Debra Walsh (Deputy Director)—National Center for Environmental Assessment-RTP Division, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Dr. Mary Ross (Branch Chief)—National Center for Environmental Assessment, U.S. Environmental
Protection Agency, Research Triangle Park, NC


Scientific Staff

Dr. Lindsay Wichers Stanek (PM Team Leader)—National Center for Environmental Assessment,
U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Jeffrey Arnold— National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC (now at Institute for Water Resources, U.S. Army Corps of
Engineers, Washington, D.C.)

Dr. Christal Bowman—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. James S. Brown—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Barbara Buckley—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Mr. Allen Davis—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Jean-Jacques Dubois—National Center for Environmental Assessment, U.S. Environmental
Protection Agency, Research Triangle Park, NC

Dr. Steven J. Dutton—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Erin Hines—National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. Douglas Johns—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Ellen Kirrane—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Dennis Kotchmar—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Thomas Long—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC
December 2009                                  xlii

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Dr. Thomas Luben—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Qingyu Meng—Oak Ridge Institute for Science and Education, Postdoctoral Research Fellow to
National Center for Environmental Assessment, U.S. Environmental Protection Agency, Research
Triangle Park, NC

Dr. Kristopher Novak—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Joseph Pinto—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Jennifer Richmond-Bryant—National Center for Environmental Assessment, U.S. Environmental
Protection Agency, Research Triangle Park, NC

Dr. Mary Ross—National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Mr. Jason Sacks—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. David Svendsgaard—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Lisa Vinikoor—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. William Wilson—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Lori White—National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC (now at National Institute for Environmental Health Sciences, Research
Triangle Park, NC)


Technical Support Staff

Mattie Arnold—Senior Environmental Employee Program, National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Laeda Baston—Senior Environmental Employee Program, National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Kimberly Branch—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Ken Breito—Senior Environmental Employee Program, National Center for Environmental Assessment,
U.S. Environmental Protection Agency, Research Triangle Park, NC

Eleanor Jamison—Senior Environmental Employee Program, National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Ryan Jones—Oak Ridge Institute for Science and Education, at National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Erica Lee—Oak Ridge Institute for Science and Education, at National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Barbara Liljequist—Senior Environmental Employee  Program, National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC
December 2009                                  xliii

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Ellen Lorang—National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Kelsey Matson—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Sandy Pham—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Olivia Phillpott—Senior Environmental Employee Program, National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Deborah Wales—National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Erica Wilson—Oak Ridge Institute for Science and Education, at National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Richard Wilson—National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Barbara Wright—Senior Environmental Employee Program, National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC
December 2009                                   xliv

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        Authors,  Contributors,  Reviewers
AUTHORS

Dr. Lindsay Wichers Stanek (PM Team Leader)—National Center for Environmental Assessment,
U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Jeffrey Arnold—National Center for Environmental Assessment,  U.S. Environmental Protection
Agency, Research Triangle Park, NC (now at Institute for Water Resources, U.S. Army Corps of
Engineers, Washington, D.C)

Dr. Christal Bowman—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. James S. Brown—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Barbara Buckley—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Mr. Allen Davis—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Jean-Jacques Dubois—National Center for Environmental Assessment, U.S. Environmental
Protection Agency, Research Triangle Park, NC

Dr. Steven J. Dutton—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Tara Greaver—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Erin Hines—National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. Douglas Johns—National Center for Environmental Assessment,  U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Ellen Kirrane—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Dennis Kotchmar—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Thomas Long—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Thomas Luben—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Qingyu Meng—Oak Ridge Institute for Science and Education, Postdoctoral Research Fellow to
National Center for Environmental Assessment, U.S. Environmental Protection Agency, Research
Triangle Park, NC

Dr. Kristopher Novak—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Joseph Pinto—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC
December 2009                                 xlv

-------
Dr. Jennifer Richmond-Bryant—National Center for Environmental Assessment, U.S. Environmental
Protection Agency, Research Triangle Park, NC
Dr. Mary Ross—National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC
Mr. Jason Sacks—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC
Dr. Timothy J. Sullivan—E&S Environmental Chemistry, Inc., Corvallis, OR
Dr. David Svendsgaard—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC
Dr. Lisa Vinikoor—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC
Dr. William Wilson—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC
Dr. Lori White— National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC (now at National Institute for Environmental Health Sciences, Research
Triangle Park, NC)
Dr. Christy Avery—University of North Carolina, Chapel Hill, NC
Dr. Kathleen Belanger —Center for Perinatal, Pediatric and Environmental Epidemiology, Yale
University, New Haven, CT
Dr. Michelle Bell—School of Forestry & Environmental Studies, Yale University, New Haven, CT
Dr. William D. Bennett—Center for Environmental Medicine, Asthma and Lung Biology, University of
North Carolina, Chapel Hill, NC
Dr. Matthew J. Campen—Lovelace Respiratory Research Institute, Albuquerque, NM
Dr. Leland B. Deck— Stratus Consulting, Inc., Washington, DC
Dr. Janneane F. Gent—Center for Perinatal, Pediatric and Environmental Epidemiology, Yale University,
New Haven, CT
Dr. Yuh-Chin Tony Huang—Department of Medicine, Division of Pulmonary Medicine, Duke University
Medical Center, Durham, NC
Dr. Kazuhiko Ito—Nelson Institute of Environmental Medicine, NYU School of Medicine, Tuxedo, NY
Mr. Marc Jackson—Integrated Laboratory Systems, Inc., Research Triangle Park, NC
Dr. Michael Kleinman—Department of Community and Environmental Medicine, University of
California, Irvine
Dr. Sergey Napelenok—National Exposure Research Laboratory, U.S. Environmental Protection Agency,
Research Triangle Park, NC
Dr. Marc Pitchford—National Oceanic and Atmospheric Administration, Las Vegas, NV
Dr. Les Recio—Genetic Toxicology Division, Integrated Laboratory Systems, Inc., Research Triangle
Park, NC
Dr. David Quincy Rich—Department of Epidemiology, University of Medicine and Dentistry of New
Jersey, Piscataway, NJ
Dr. Timothy Sullivan— E&S Environmental Chemistry, Inc., Corvallis, OR
Dr. George Thurston—Department of Environmental Medicine, NYU, Tuxedo, NY
December 2009                                   xlvi

-------
Dr. Gregory Wellenius—Cardiovascular Epidemiology Research Unit, Beth Israel Deaconess Medical
Center, Boston, MA

Dr. Eric Whitsel—Departments of Epidemiology and Medicine, University of North Carolina, Chapel
Hill, NC


CONTRIBUTORS

Dr. Philip Bromberg—Department of Medicine, University of North Carolina, Chapel Hill, NC

Mr. Michael Burr—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Mr. Turhan Carroll—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Ms. Rosana Datti—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Mr. Neil Frank—Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Mr. Jonathan Krug—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Ms. Katie Lane—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Mr. Phil Lorang—Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Ms. Christina Miller—National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Ms. Irina Mordukhovich—Oak Ridge Institute for Science and Education, at National Center for
Environmental Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Elizabeth Oesterling Owens—National Center for Environmental Assessment, U.S. Environmental
Protection Agency,  Research Triangle Park, NC

Dr. Adam Reff—Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Ms. Victoria Sandiford— Office of Air Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Mark Schmidt—Office of Air Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Ms. Angelina Schultz—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Ms. Kirsten Simmons—Student Services Contractor, National Center for Environmental Assessment,
U.S. Environmental Protection Agency, Research Triangle Park, NC

Ms. Genee  Smith—Oak Ridge Institute for Science and Education, at National Center for Environmental
Assessment, U.S. Environmental Protection Agency, Research Triangle Park, NC

Mr. Kurt Susdorf—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Dr. Barbara Turpin—Department of Environmental Sciences, Rutgers University, New Brunswick, NJ
December 2009                                   xlvii

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Ms. Lauren Turtle—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC
Ms. Rebecca Yang—Student Services Contractor, National Center for Environmental Assessment, U.S.
Environmental Protection Agency, Research Triangle Park, NC

PEER REVIEWERS
Dr. Sara Dubowsky Adar, Department of Epidemiology, University of Washington, Seattle, WA
Mr. Chad Bailey, Office of Transportation and Air Quality, Ann Arbor, MI
Mr. Richard Baldauf, Office of Transportation and Air Quality, Ann Arbor, MI
Dr. Prakash Bhave, National Exposure Research Laboratory, U.S. Environmental Protection Agency,
Research Triangle Park, NC
Mr. George Bowker, Office of Atmospheric Programs, U.S. Environmental Protection Agency,
Washington, D.C.
Dr. Judith Chow, Division of Atmospheric Sciences, Desert Research Institute, Reno, NV
Dr. Dan Costa, U.S. Environmental Protection Agency, Research Triangle Park, NC
Dr. Ila Cote, National Center for Environmental Assessment, U.S. Environmental Protection Agency,
Research Triangle Park, NC
Dr. Robert Devlin, National Health and Environmental Effects Research Laboratory, U.S. Environmental
Protection Agency, Research Triangle Park, NC
Dr. David DeMarini, National Health and Environmental Effects Research Laboratory, U.S.
Environmental Protection Agency, Research Triangle Park, NC
Dr. Neil Donahue, Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA
Dr. Aimen Farraj, National Health and Environmental Effects Research Laboratory, U.S. Environmental
Protection Agency, Research Triangle Park, NC
Dr. Mark Frampton, Department of Environmental Medicine, University of Rochester Medical Center,
Rochester, NY
Mr. Neil Frank, Office of Air Quality Planning and Standards, U.S. Environmental  Protection Agency,
Research Triangle Park, NC
Mr. Tyler Fox, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC
Dr. Jim Gauderman, Department of Environmental Medicine, Department of Preventive Medicine,
University of Southern California, Los Angeles, CA
Dr. Barbara Glenn, National Center for Environmental Research, U.S. Environmental Protection Agency,
Washington, D.C.
Dr. Terry Gordon, School of Medicine, New York University, Tuxedo, NY
Mr. Tim Hanley,  Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC
Dr. Jack Harkema, Department of Pathobiology and Diagnostic Investigation, Michigan State University,
East Lansing, MI
Ms. Beth Hassett-Sipple, Office of Air Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC
December 2009                                  xlviii

-------
Dr. Amy Herring, Department of Biostatistics, University of North Carolina, Chapel Hill, NC

Dr. Israel Jirak, Department of Meteorology, Embry-Riddle Aeronautical University, Prescott, AZ

Dr. Mike Kleeman, Department of Civil and Environmental Engineering, University of California, Davis,
CA

Dr. Petros Koutrakis, Exposure, Epidemiology and Risk Program, Harvard School of Public Health,
Boston, MA

Dr. Sagar Krupa, Department of Plant Pathology, University of Minnesota, St. Paul, MN

Mr. John Langstaff, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. Meredith Lassiter, Office of Air Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Mr. Phil Lorang, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. Karen Martin, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Ms. Connie Meacham, National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Mr. Tom Pace, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. Jennifer Peel, Department of Environmental and Radiological Health Sciences, College of Veterinary
Medicine and Biomedical Sciences,  Colorado State University, Fort Collins, CO

Dr. Zackary Pekar, Office of Air Quality  Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Mr. Rob Pinder, National Exposure Research Laboratory, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Mr. Norm Possiel, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. Sanjay Rajagopalan, Division of Cardiovascular Medicine, Ohio State University, Columbus, OH

Dr. Pradeep Rajan, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Mr. Venkatesh Rao, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Ms. Joann Rice, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Mr. Harvey Richmond, Office of Air Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Ms. Victoria Sandiford, Office of Air Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Stefanie Sarnat, Department of Environmental and Occupational Health, Emory University, Atlanta,
GA

Dr. Frances Silverman, Gage Occupational and Environmental Health, University of Toronto, Toronto,
ON
December 2009                                   xlix

-------
Mr. Steven Silverman, Office of General Council, U.S. Environmental Protection Agency, Washington,
D.C.

Dr. Barbara Turpin, Department of Environmental Sciences, Rutgers University, New Brunswick, NJ

Dr. Robert Vanderpool, National Exposure Research Laboratory, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. John Vandenberg (Director)—National Center for Environmental Assessment-RTP Division, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Dr. Alan Vette, National Exposure Research Laboratory, U.S. Environmental Protection Agency, Research
Triangle Park, NC

Ms. Debra Walsh (Deputy Director)—National Center for Environmental Assessment-RTP Division, U.S.
Environmental Protection Agency, Research Triangle Park, NC

Mr. Tim Watkins, National Exposure Research Laboratory, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. Christopher Weaver, National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Mr. Lewis Weinstock, Office of Air Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Ms. Karen Wesson, Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. Jason West, Department of Environmental Sciences and Engineering, University of North Carolina,
Chapel Hill, NC

Mr. Ronald Williams, National Exposure Research Laboratory, U.S. Environmental Protection Agency,
Research Triangle Park, NC

Dr. George Woodall, National Center for Environmental Assessment, U.S. Environmental Protection
Agency, Research Triangle Park, NC

Dr. Antonella Zanobetti, Department of Environmental Health, Harvard School of Public Health, Boston,
MA
December 2009

-------
 Clean Air Scientific Advisory Committee
             for Particulate Matter NAAQS
CHAIRPERSON
Dr. Jonathan Samet, Department of Preventive Medicine, Keck School of Medicine, University of
Southern California, Los Angeles, CA

MEMBERS
Dr. Lowell Ashbaugh, Crocker Nuclear Lab, University of California, Davis, CA
Dr. Ed Avol, Department of Preventive Medicine, Keck School of Medicine, University of Southern
California, Los Angeles, CA
Dr. Joseph Brain*, Department of Environmental Health, Harvard School of Public Health, Harvard
University, Boston, MA
Dr. Wayne Cascio, Brody School of Medicine, East Carolina University, Greenville, NC
Dr. Ellis B. Cowling*, Colleges of Natural Resources and Agriculture and Life Sciences, North Carolina
State University, Raleigh, NC
Dr. James Crapo*, Department of Medicine, National Jewish Medical and Research Center, Denver, CO
Dr. Douglas Crawford-Brown, Department of Environmental Sciences and Engineering, University of
North Carolina at Chapel Hill, Chapel Hill, NC
Dr. H. Christopher Frey*, Department of Civil, Construction and Environmental Engineering, College of
Engineering, North Carolina State University, Raleigh, NC
Dr. David Grantz, Botany and Plant Sciences and Air Pollution Research Center, Riverside Campus and
Kearney Agricultural Center, University of California, Parlier, CA
Dr. Joseph Helble, Thayer School of Engineering, Dartmouth College, Hanover, NH
Dr. Rogene Henderson**, Lovelace Respiratory Research Institute, Albuquerque, NM
Dr. Philip Hopke, Department of Chemical Engineering, Clarkson University, Potsdam, NY
Dr. Donna Kenski*, Lake Michigan Air Directors Consortium, Rosemont, IL
Dr. Morton Lippmann, Nelson Institute of Environmental Medicine, New York University School of
Medicine, Tuxedo, NY
Dr. Helen Suh Macintosh, Environmental Health, School of Public Health, Harvard University, Boston,
MA
Dr. William Malm, National Park Service Air Resources Division, Cooperative Institute for Research in
the Atmosphere, Colorado State University, Fort Collins, CO
Mr. Charles Thomas (Tom) Moore, Jr., Western Regional Air Partnership, Western Governors'
Association, Fort Collins, CO
December 2009

-------
Dr. Robert F. Phalen, Center for Occupation & Environment Health, College of Medicine, Department of
Community and Environmental Medicine, Air Pollution Health Effects Laboratory, University of
California Irvine, Irvine, CA

Dr. Kent Pinkerton, Center for Health and the Environment, University of California, Davis, CA

Mr. Richard L. Poirot, Air Pollution Control Division, Department of Environmental Conservation,
Vermont Agency of Natural Resources, Waterbury, VT

Dr. Armistead (Ted) Russell*, Department of Civil and Environmental Engineering, Georgia Institute of
Technology, Atlanta, GA

Dr. Frank Speizer, Channing Laboratory, Harvard Medical School, Boston, MA

Dr. Sverre Vedal, Department of Environmental and Occupational Health Sciences, School of Public
Health and Community Medicine, University of Washington, Seattle, WA

* Members of the statutory Clean Air Scientific Advisory Committee (CAS AC) appointed by the EPA
Administrator.

**As immediate past CASAC Chair, Dr. Henderson is invited to participate in CASAC advisory activities
for FY 2009.


SCIENCE ADVISORY BOARD STAFF

Dr. Holly Stallworth, Economist and Designated Federal Officer, Clean Air Scientific Advisory
Committee, Environmental Economics Advisory Committee, Washington, D.C.
December 2009

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             Acronyms  and Abbreviations








           a                alpha, ambient exposure factor



           a-HCH           alpha-hexachlorocyclohexane



           A                Angstrom



           A                surface albedo



           AAC             abdominal aortic calcium



           AAS             atomic absorption spectrophotometry



           AB               Alcian Blue stain



           ABC             Asian Brown Cloud



           ABI              ankle-arm or resting blood pressure index



           AC               air conditioning



           Ace              acenaphthene



           ACE-1            angiotensin converting enzyme-1



           ACEAsia          (Asian Pacific Regional) Aerosol Characterization Experiment



           ACGIH           American Conference of Governmental Industrial Hygienists



           ACh             acetylcholine



           Acl              acenaphthylene



           ACP             accumulation mode particle



           ACS             American Cancer Society



           Ad4BP           adrenal-4-binding protein



           ADEOS-1         Advanced Earth Observing Satellite-1



           A-DEP           automobile diesel exhaust particles



           ADM            angular distribution model(s), angular dependence model



           ADMA           asymmetric dimethylarginine



           AD-Net           Asian Dust Network



           Ae               AERONET



           AeroCom          Aerosol Comparisons between Observations and Models



           AERONET        NASA AERosol RObotic NETwork



           AF               atrial fibrillation



           AGA             appropriate for gestational age



           AGE             advanced glycation end product



           AHR             airway hyperresponsiveness, airway hyperreactivity



           AhR             arylhydrocarbon receptor
December 2009

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             AH SMOG



             AI



             AIC



             AIM



             AIOP



             AIRS



             Al



             ALI



             AM



             AM,AMF



             AMAP



             AMDP



             AMI



             AMS



             Angll



             ANOVA



             ANP



             ANS



             Ant



             AOD



             AP-1



             APC



             APCS



             APEX



             APHEA



             APO



             ApoE



             APS



             aPTT



             AQCD



             AQI



             AQM



             AQS



             Aqua



             AR4
California Seventh Day Adventist study



aerosol index



Akaike's information criterion



ambient ion monitor



2003 Aerosol Intensive Operating Period



Aerometric Information Retrieval System



aluminum



air liquid interface



alveolar macrophage(s)



arbuscular mycorrhizal



Arctic Monitoring and Assessment Programme



annual maximum of daily precipitation



acute myocardial infarction



aerosol mass spectrometry



angiotensin II



analysis of variance



atrial natriuretic peptide



autonomic nervous system



anthracene



aerosol optical depth



activator protein 1



antigen presenting cell(s)



Absolute Principal Components Scores



Air Pollutants Exposure Model



Air pollution and Health: a European Approach



apocynin



apolipoprotein E



aerodynamic particle sizer, aerosol polarimetry sensor



activated partial thromboplastin time



Air Quality Criteria Document



Air Quality Index



air quality model



U.S.  EPA Air Quality System database



NASA satellite



Fourth Assessment Report (AR4) from the IPCC
December 2009
                    liv

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             ARCTAS


             ARD

             ARDS

             ARI

             ARIC

             ARIES

             ARM

             ARQM


             ARS

             As

             ASDNN5


             ASOS

             ATOFMS

             ATP

             A- Train


             ATS

             AURA

             avg

             AVHRR

             B

             P-HCH

             3PHSD

             PTGF
             Ba

             BaA

             BAD

             BAL

             BALB/c
Arctic Research of the Composition of the Troposphere from Aircraft
and Satellites

Air Resources Division

adult respiratory distress syndrome

acute respiratory infection

Atherosclerosis Risk in Communities study

Aerosol Research and Inhalation Epidemiology Study

Atmospheric Radiation Measurement program

Air Quality Research Branch (Meteorological Service of Canada
Toronto)

Air Resource Specialists

arsenic

mean of the standard deviation in all 5-min segments of a EKG 24 h
recording

Automated Surface Observing System

aerosol time-of-flight mass spectrometry

adenosine triphosphate

a group  of 5 afternoon overpass satellites (Aura, PARASOL,
CALIPSO, CloudSat, Aqua)

American Thoracic Society

NASA satellite

average

Advanced Very High Resolution Radiometer

beta, beta coefficient, slope

beta-hexachlorocyclohexane(s)

3 p-hydroxysteroid dehydrogenase

P transforming growth factor

absorption by gases coefficient

absorption by particles coefficient

light extinction coefficient

scattering by gases coefficient

sum of light scattering by (aerosol) particles coefficient

barium

benz[a]anthracene

bronchial artery diameter

bronchoalveolar lavage

albino inbred mouse strain
December 2009

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             BALF              bronchoalveolar lavage fluid



             BALT              bronchus-associated lymphoid tissues



             BAM               beta attenuation monitor



             BaP                benzo[a]pyrene



             BASIC              Brain Attack Surveillance in Corpus Christi



             BASE-A            Burning Airborne and Spaceborne Experiment - Amazon and Brazil



             BbF                benzo[b]fluoranthene



             BC                 black carbon



             BCC-CMI           Beijing Climate Center - Carbon Mitigation Initiative



             BCCR              Bjerknes Centre for Climate Research



             BeP                benz[e]pyrene



             BghiP, BpPe         benzo[g,h,i]perylene



             BGT                beta-gauge technique



             BH4                tetrahydrobiopterin



             bhp                 brake horsepower



             BkF                benzo[k]fluoranthene



             BMI                body mass index



             BMP                bone morphogenetic protein



             BN/BR              Brown Norway rat strain



             BNP                brain natriuretic peptide, B-type natriuretic peptide



             BOSS              BYU Organic Sampling System



             BP                 blood pressure



             BPM                blowing PM2.5



             BpPe                benzo[ghi]perylene



             BPQ                benz(ayrene (BaP)-quinone



             Br                  bromine



             BRAVO             Big Bend Regional Aerosol and Visibility Observational (Study)



             BrdU               bromodeoxyuridine



             BS                 black smoke



             BUG                bucillamine (N-[2-mercapto-2-methylpropionyl]-L-cysteine)



             B VAIT              B-Vitamin Atherosclerosis Intervention Trial



             BYU                Brigham Young University



             C                   carbon



             C4                  Center of Clouds, Chemistry and Climate



             12C                 carbon-12
December 2009
Ivi

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             C60(OH)24

             Ca

             CAA

             CAAA

             CAAM

             CAC

             CaCO3

             CAD

             CALINE

             CALIOP

             CALIPSO

             CAM

             CAMM

             CAMP

             CAMx

             Ca(NO3)2

             CAP

             CAPMoN

             CASAC

             CaSO4

             CASTNet

             CATS

             CB

             CB-Fe

             CB(P)

             CBSA

             CB-V


             CBVD

             CC16

             CCCma

             CCM3

             CCN

             CCPM
carbon-13

carbon-14

water-soluble fullerene

calcium

Clean Air Act

1977 Clean Air Act Amendments

continuous ambient mass monitor

coronary artery calcification

calcium carbonate

coronary artery disease

California Line Source Dispersion Model

Cloud and Aerosol Lidar with Orthogonal Polarization

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations

Community Atmosphere Model

continuous ambient mass monitor

Childhood Asthma Management Program

comprehensive air quality model with extensions

calcium nitrate

concentrated ambient particle

Canadian Air and Precipitation Monitoring Network

Clean Air Scientific Advisory Committee

calcium sulfate

Clean Air Status and Trends Network

cumulative air toxics surface

carbon black, chronic bronchitis

carbon black particles artificially coated with Fe(II) salt.

carbon black (particles)

Core-Based Statistical Area

carbon black particles artificially coated with a targeted concentration
of Vanadium (IV) salt

cerebrovascular disease

Clara cell protein, Clara cell 16 protein

Canadian Centre for Climate Modeling and Analysis

Community Climate Model

cloud condensation nuclei

continuous coarse particle monitor
December 2009

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             CCSM3

             CCSP

             Cd

             CDC

             CDE

             CDNC

             CDPHE

             Ce

             CEN

             CenRAP

             CERES

             CERFACS


             CF

             CFA

             CFD

             CFR

             CGCM3.1

             cGMP

             CH2C12

             CH2O

             CH4

             CHAD

             CHD

             CHF

             CHL

             CHO

             Chr

             CHS

             CI

             GIF

             CUT

             CIMT

             Cl

             CL

             CLAMS
Community climate system model, version 3

Climate Change Science Program

cadmium

Centers for Disease Control and Prevention

conjugated diene

cloud droplet number concentration

Colorado Department of Public Health and Environment

cerium

European Committee for Standardization

Central Regional Air Planning Association

Clouds and the Earth's Radiant Energy System

European Centre for Research and Advanced Training in Scientific
Computation

coronary flow, cystic fibrosis

coal fly ash

cystic fibrosis disease

Code of Federal Regulations

Coupled global climate model

cyclic guanosine monophosphate

methylene chloride

formaldehyde

methane

Consolidated Human Activity Database

chronic heart disease

congestive heart failure

crown heel length

Chinese hamster ovary cells

chrysene

Children's Health Study

confidence interval

carbon-impregnated charcoal filter

Chemical Industry Institute of Toxicology

carotid intimal-medial thickness

chlorine

chemiluminescence

Chesapeake Lighthouse and Aircraft Measurements for Satellites
December 2009

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             CM



             CMAQ



             CMAR



             CMB



             CMD



             ONES



             CNP



             CNRM



             CNRM



             CNS



             Co



             CO



             C02



             COD



             COH, CoH



             CONUS
             COPD



             CoPP



             COX-2



             CPC



             CPZ



             Cr



             C-R



             CRP



             Cs



             137Cs



             CS



             CSA



             CSC



             CSE



             cSHMT



             CSIRO



             CSN



             CTM
conditioned medium, cell culture medium



Community Multi-scale Air Quality modeling system



CSIRO Marine and Atmospheric Research



chemical mass balance



count median diameter



Centre National d"Etudes Spatiales



carbon nano particle



Centre National de Recherches Meteorologiques



Center National Weather Research



central nervous system



cobalt



carbon monoxide



carbon dioxide



coefficient of divergence



coefficient of haze



continental United States



carboxyl group



chronic obstructive pulmonary disease



cobalt protoporphyrin



cyclooxygenase 2 enzyme



condensation particle counter



capsazepine



chromium



concentration-response (relationship)



C-reactive protein



cesium



cesium-137



cigarette smoke



Combined Statistical Area



cigarette smoke condensates



cigarette smoke extract



cytosolic serine hydroxymethyltransferase



Commonwealth Scientific and Industrial Research Organization



Chemical Speciation Network



chemistry-transport model, chemical transport model
December 2009
                    lix

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             Cu                  copper



             CuSO4               copper sulfate



             Cu/Zn SOD          Cu/Zn superoxide dismutase



             CUP                Current Use Pesticide



             CV                  cardiovascular, coefficient of variation



             CVD                cardiovascular disease(s)



             CVM                contingent valuation method



             GYP                cytochrome P450



             CYP 1A1            cytochrome P450 1A1



             A                   delta, change, difference



             AFEVj               change in forced expiratory volume in one second



             d50                  50 percent cut point or 50 percent diameter



             dae                  aerodynamic diameter of a particle



             D                   diameter



             Da                  Dalton



             DAAC               Distributed Active Archive Center



             DAASS             Dry Ambient Aerosol Size Spectrometer



             DABEX             Dust and Biomass-burning Experiment (in West Africa)



             DAR                denuded aortic ring



             DAX-1              x-chromosome gene-1



             DBA                dibenzo(a,hnthracene



             DBF                diastolic blood pressure



             DC                  dendritic cell



             DC                  diesel exhaust particles + cigarette smoke condensates



             DCS                Douglas aircraft



             DCF                direct climate forcing, 2',7'-dichlorofluorescin



             DDT                dichlorodiphenyltrichloroethane



             DE                  diesel exhaust



             DEE                diesel exhaust extract



             DEP                diesel exhaust particle



             DEPAL              diesel exhaust particles aliphatic (extract)



             DEPAR             diesel exhaust particles aromatic (extract)



             DEPE               diesel exhaust particles extract



             DEPM               diesel exhaust particles methanol (extract)



             DEPME             diesel exhaust particles methylene chloride extract
December 2009

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             DEPPO             diesel exhaust particles polar (extract)



             Dex                dexamethasone



             dF\d                change fold, unit change in property



             DFO                desferrioxamine (Desferral) an iron chelator



             DFX                deferasirox (Exjade) an oral iron chelator



             DHR               dihydrorhodamine 123



             DLCO              carbon monoxide diffusing capacity



             DMEM             Dulbecco's modified Eagle's medium (culture medium)



             DMSO              dimethyl sulfoxide



             DMT1              divalent metal transporter-1 protein



             DMTU              dimethylthiourea



             DNA               deoxyribonucleic acid



             DOE                U.S. Department of Energy



             dpc                 days post conception



             DPC                dodecylphosphocholine



             DPCC              1,2-dipalmitoyl-SN-glycero-3-phosphocholine



             DPI                diphenyleneiodonium



             DPM               diesel particulate matter



             DPPC              dipalmitoylphosphatidylcholine



             DRE                direct radiative effects



             DRF                direct radiative forcing



             DRUM              Davis Rotating Uniform size-cut Monitor



             DS                 diffusion screens



             DSP                daily sperm production



             DTMA              Dynamic mechanical thermal analysis



             DTPA              diethylene triamine pentaacetic acid



             DU                 dust



             dv                  deciview(s)



             DVT                deep vein thrombosis



             EAD                electrical aerosol detector



             EANET             Acid Deposition Monitoring Network in East Asia



             EARLINET         European Aerosol Research Lidar Network



             EarthCARE         Earth Clouds, Aerosols and Radiation Explorer



             EAST-AIRE         East Asian Study for Tropospheric Aerosols



             EBCT              electron beam computed tomography
December 2009
Ixi

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             EC

             ECE-1

             EGG, EKG

             ECHAM5

             ECHO-G

             ECRHS

             EC/TC

             ED

             EDGAR

             EDTA

             ED-XRF

             EGM

             EGU

             EHC-93


             EKG, EGG

             ELISA

             EMECAS


             EMEP

             eNO

             eNOS

             EOS

             EPA

             ER

             ERBS

             ERK1/2

             ESRL

             ESTR

             ET

             ET

             ET

             ETA

             ETB

             ETS

             EU
elemental carbon

endothelin converting enzyme-1

electrocardiogram

European Centre Hamburg with Hamburg Aerosol Module

(ECHAM4 + HOPE-G):

European Community Respiratory Health Survey

ratio of elemental carbon to total carbon

emergency room, emergency department

Emissions Database for Global Atmospheric Research

ethylenediaminetetraacetic acid

energy dispersive X-ray fluorescence

electrogram

electricity-generating unit

Ottawa dust; urban air particulate matter PMi0, collected in 1993 in
Ottawa, Canada

 electrocardiogram

enzyme-linked immunosorbent assay

Spanish Multi-centric Study on the Relation between Air Pollution
and Health

European Monitoring and Evaluation Programme

exhaled nitric oxide

endothelial nitric oxide synthase

Earth Observing System

U.S. Environmental Protection Agency

estrogen receptor

Earth Radiation Budget Satellite

ERK-1 (MAPK p42) and ERK-2 (MAPK p44)

Earth System Research Laboratory

expanded simple tandem repeat

forcing efficiency

extrathoracic region

endothelin

endothelin A receptor subtype

endothelin B receptor subtype

environmental tobacco smoke

endotoxin units
December 2009
                   Ixii

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             F                   breathing frequency

             f                    the ratio of ambient aerosol mass (wet) to dry aerosol mass M.

             fasp(RH)            total light scattering coefficient at given relative humidity(RH) values

             faf                  anthropogenic fraction of fine-mode fraction

             ff                   fine mode fraction

             f(RH)                the unitless water growth term that depends on relative humidity

             F                    fine particles

             F344                Fisher 344 strain of rats

             Fa                  adjusted forcings

             FA                  filtered air

             FAC                 ferric ammonium citrate

             FBI                 Federal Bureau of Investigation

             FBS                 fetal bovine serum

             PCS                 fetal calf serum

             FDMS               Filter Dynamics Measurement System

             FDMS-TEOM       Filter Dynamics Measurement System - Tapered Element Oscillating
                                  Microbalance

             Fe                  effective (Fe) forcings

             Fe                  iron

             Fe2(SO4)3            ferric sulfate

             FeCl3                ferric chloride

             FEF                 forced expiratory flow

             FEF25_75             mean forced expiratory flow over the middle half of the forced vital
                                  capacity

             FEF50o/0              mid-expiratory flow

             FEM                Federal Equivalent Method

             FeNO               fractional exhaled nitric oxide

             FERA               Fire and Environmental Research Applications (Team)

             FEV]                forced expiratory volume in one second

             FGA                one fibrinogen alpha chain

             FOB                 one fibrinogen beta chain

             FGOALS-gl.O       Flexible Global Ocean-Atmosphere-Land System Model

             Fi                  instantaneous forcing

             FID                 flame ionization detection

             FIMS                fast integrated mobility scanners

             Fjnf                 infiltration factors
December 2009
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             FKHR              Proapoptotic Factor FOXO1

             Fie                 fluorine

             Flu                 fluoranthene

             FMD               flow-mediated dilation

             FPG                formamidopyrimidine-DNA glycosylase

             f-PM, FPM          fine particulate matter

             FR                 Federal Register

             FRM               Federal Reference Method

             FROSTFIRE        The landscape-scale prescribed research burn in the boreal forest of
                                 interior Alaska, July 1999; conducted by FERA.

             Fs                  SST forcing(s), forcing driven by sea surface temperature (SST)

             Fsfc                mean net solar flux at the (Earth) surface

             FT                 free troposphere

             FTIR               Fourier transform infrared spectrometry

             F/UFP              mix of fine and ultrafine particles, all < 2.5 |im

             FVC                forced vital capacity

             yGCS               gamma glutamylcysteine sythetase

             Ga                 gallium

             GAM               generalized additive model

             GATOR             Gas, Aerosol, Transport, and Radiation model

             GATORG           Gas, Aerosol, Transport, Radiation, and General circulation model

             GAW               Global Atmospheric Watch network

             GBS                group B streptococcus

             GC                 gas chromatography

             GCM(s)             general circulation model(s), global climate model

             GCMOM           General Circulation, Mesoscale and Ocean Model

             GC/MS             gas chromatography/mass spectrometry

             GCS                gamma glutamylcysteine sythetase

             GD                 gestational day

             GDF                growth differentiation factor (e.g., GDF-9)

             GEE                generalized estimating equations, gasoline engine exhaust

             GEIA               Global Emissions Inventory Activity

             GEM               gaseous elemental mercury

             GEOS-Chem        Goddard Earth Observing System-CHEMistry

             GFAAS             graphite furnace atomic absorption spectrometry

             GFAP               glial fibrillatory acidic protein
December 2009
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             GFDL               Geophysical Fluid Dynamics Laboratory

             GFDL-CM2.X        GFDL Climate Models

             GFED               Global Fire Emission Database

             GGT                gamma-glutamyltranspeptidase

             GHG                greenhouse gas

             GIS                 Geographic Information System

             GISS                Goddard Institute for Space Studies

             GISS-AOM          GISS Atmosphere-Ocean Model climate prediction model

             GISS-EH            GISS AOM for sea ice model

             GIS S-ER            GIS S AOM for liquid sea model

             GLAS               Geoscience Laser Altimeter System

             GLM                generalized linear models

             GM                 geometric mean

             GM-CSF            granulocyte macrophage colony-stimulating factor

             GMD               Global Monitoring Division

             GMS                Greater Mekong Subregion

             GOCART            Goddard Chemistry Aerosol Radiation and Transport

             GOES               Geostationary Operational Environmental Satellite

             GoMACCS          Gulf of Mexico Atmospheric Composition and Climate Study

             GPS                Global Positioning System

             GSD                geometric standard deviation

             GSFC               NASA Goddard Space Flight Center

             GSH                glutathione

             GSFLGSSG          ratio of reduced glutathione to glutathione disulfide (oxidized
                                 glutathione)

             GSO, GSNO         S-Nitrosoglutathione

             GSSG               glutathione disulfide; oxidized glutathione

             GST                glutathione-S-transferase

             GSTM1             glutathione S-transferase polymorphism Ml

             GSTP1              glutathione-S-transferase polymorphism PI

             GSTT1              glutathione-S-transferase polymorphism Tl

             GWP                global warming potential

             h                   hour

             H                   atomic hydrogen, hydrogen radical, height, heart rate, high dose, high
                                 exposure

             H+                  hydrogen ion
December 2009
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             HR                 heart rate

             H2                  molecular hydrogen

             H2CO               formaldehyde

             H2O                water

             H2O2                hydrogen peroxide

             H2S                 hydrogen sulfide

             H2SO4              sulfuric acid

             H9c2                rat embryonic cardiomyocytes cell line

             HA                 hospital admission

             HAEC              Human Aortic Endothelial Cell

             HAPC              Harvard ambient particle concentrator

             HBE, HBEC         Human Bronchial Epithelial cells

             HC                 hydrocarbon(s); head circumference

             HCB                hexachlorobenzene

             HCH                hexachlorocyclohexane(s) (e.g. a-HCH, P-HCH)

             HDL                high density lipoprotein

             HEAPSS            Health Effects of Air Pollution among Susceptible Subpopulations
                                 study

             HEI                 Health Effects Institute

             HEPA               high efficiency particle air (filter)

             HERO              Health and Environmental Research Online, NCEA Database System

             HF                 heart failure, high frequency (HRV parameter), high (dose/exposure)
                                 filtered

             HFCD              High-Fat Chow Diet

             HFE                HFE gene, HFE protein

             Hg                 mercury

             Hg(0)               gaseous elemental mercury

             Hg(II)               gaseous divalent (oxidized) mercury

             HH                 hereditary hemochromatosis

             HNRS              Hans Nixdorf Recall Study

             HO-1                heme oxygenase-1

             hOGGl              8-hydroxyguanine DNA-glycosylase

             HOPE-G            Hamburg Atmosphere-Ocean Coupled Circulation Model

             hPA                 hectopascal

             hPAEC              human pulmonary artery endothelial cells

             hPBMC             human peripheral blood mononuclear cells
December 2009
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             HPLC

             HPMF

             hPMVEC

             HR

             HRV

             HSD

             HSP-70

             HSPH

             HSRL

             HUVEC

             hv

             HWS

             Hz

             1C

             ICAM-1

             ICARTT


             ICAS

             ICD

             ICD-9

             ICD-10

             ICESat

             ICP-AES

             ICP-MS

             ICR

             ICRP

             IDP

             IFN-y

             IPS

             Ig

             IGS

             IHD

             IIASA

             IL

             iMDDC
high pressure liquid chromatography

high particulate matter filtered

human pulmonary microvascular endothelial cells

heart rate, hazard ratio, high level DE

heart rate variability

17p-hydroxysteroid dehydrogenase

heat shock protein

Harvard School of Public Health

High Spectral Resolution Lidar

human umbilical vein endothelial cells

photon

hardwood smoke

hertz

ion chromatography

intercellular adhesion molecule-1

International Consortium for Atmospheric Research on Transport and
Transformation

Inner-City Asthma Study

implantable/implanted cardioverter defibrillator

International Classification of Disease 9th revision

International Classification of Disease 1 Oth revision

Ice, Cloud and land Elevation Satellite

inductively coupled plasma-atomic emission spectroscopy

inductively-coupled plasma-mass spectrometry

imprinting control region, mouse strain

International Commission on Radiological Protection

indenof 1,2,3-c,d]pyrene

interferon-gamma

Integrated Forest Study

immunoglobulin (e.g., IgE)

International Genetic Standard

ischemic heart disease

International Institute for Applied Systems Analysis

interleukin

immature monocyte-derived dendritic cells
December 2009
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             IMPACT             Interactive Modeling Project for Atmospheric Chemistry and
                                  Transport

             IMPROVE           Interagency Monitoring of Protected Visual Environment

             IN                  ice nuclei

             INAA               instrumental neutron activation analysis

             INCA               Interactions between Chemistry and Aerosol

             INDOEX            Indian Ocean Experiment

             INGV-SXG          Istituto Nazionale di Geofisica e Vulcanologia coupled to SINTEX-G

             INM-CM3.0         Institute of Numerical Mathematics climate model

             iNOS                inducible nitric oxide synthase

             INTEX              Intercontinental Chemical Transport Experiment

             I/O                  indoor-outdoor ratio

             IOM                Institute of Medicine

             i.p.                  intraperitoneal

             IP                   inhalable particle

             IPCC                Intergovernmental Panel on Climate Change

             IPSL-CM4           Institut Pierre Simon Laplace climate model

             IQR                 interquartile range

             Ir                   iridium

             IR                  incidence rate, infrared radiation

             IRE                 iron responsive element

             IRMS               isotope ratio mass spectrometer

             ISA                 Integrated Science Assessment

             ISO                 International Standards Organization

             ISO                 isoprene, 2-methyl analog of 1,3-butadiene

             IT                   intratracheal, intratracheally

             IUGG               International Union of Geodesy and Geophysics

             IUGR               intrauterine growth restriction, intrauterine growth retardation

             i.v.                  intravenous

             JNK                 c-jun N-terminal kinase

             KB                  kappa B

             K                   potassium

             KG                  local neutrophil chemoattractant protein

             kHz                 kilohertz

             kJ                   kilojoules

             KLH                keyhole limpet hemocyanin
December 2009
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             km                 kilometer



             km"1                inverse kilometer



             Kow                 octanol-water partition coefficient



             L, dL, mL, uL        Liter, deciLiter, milliLiter, microLiter



             L                   low



             La                 lanthanum



             LAC                light-absorbing carbon



             LACE98            Lindenberg Aerosol Characterization Experiment 1998



             LBA-SMOCC        Large-Scale Atmosphere-Biosphere Experiment in Amazon



             LEW               low birth weight



             LC                 lethal concentration



             LC50                median lethal concentration



             LDH                lactate dehydrogenase



             LDL                low-density lipoprotein



             LDLR              low-density lipoprotein receptor



             LDVP              left developing ventricular pressure



             LES                large eddy simulations model



             LF                 low frequency an HRV parameter



             LF/HF              ratio of LF to HF an HRV parameter



             LIBS                laser induced breakdown spectroscopy



             LIF                 leukemia inhibitory factor



             LITE                Lidar In-space Technology Experiment



             LMD               Laboratoire de Meteorologie Dynamique



             LMDz              LMD with Zoom



             LMDZ-INCA        LMDZ INteractive Chemistry and Aerosols model



             LMDZ-LOA         LMDZ with Laboratoire d'Optique Atmospherique model



             L-NAME            arginine analog; N(G)-nitro-L- arginine methyl ester



             L-NMMA           N(G)-mono-methyl-L-arginine



             LnRMSSD          natural log of RMSSD; measure of HRV



             InSDNN            natural log of the standard deviation of NN intervals in an EKG



             LOA                Laboratoire d'Optique Atmospherique



             LOESS             locally weighted scatterplot smoothing



             LOSU              level of scientific understanding



             Lpm                liters per minute (L/min)



             LPMF              low particulate matter filtered
December 2009
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             LPO                plasma lipid peroxides



             LPS                lipopolysaccharide



             LRAT               long range atmospheric transport



             LROT              long range oceanic transport



             LSCE               Laboratoire des Sciences du Climat et de l'Environnement



             LSDF               low-sulfur diesel fuel



             LTB4               leukotriene B4



             LTE4               leukotriene E4



             LUA NRW          The North Rhine-Westphalia State Environment Agency



             LUDEP             LUng Dose Evaluation Program



             LUR               land use regression



             LV                 left ventricle



             LVEDP             left-ventricular end-diastolic pressure,



             LVSP               left-ventricular systolic pressure, left ventricular developed pressure



             L/W                ratio of lumen to wall



             LWC               liquid water content



             LWDE              Low Whole Diesel Exhaust



             LWP               liquid water path



             jig                 microgram



             Hg/m3               micrograms per cubic meter



             |im                 micrometer, micron



             m, cm, \im, nm       meter(s), centimeter(s), micrometer(s), nanometer(s)



             M, mM, uM, nM, pM Molar, milliMolar, microMolar, nanoMolar, picoMolar



             M                  dry aerosol mass, medium dose/exposure



             ma                 moving average



             MAM               March-April-May



             MAN               Maritime Aerosol Network



             MANE-VU          Mid-Atlantic/Northeast Visibility Union



             MAP               mitogen-activated protein, mean arterial pressure



             MAPK              mitogen-activated protein kinase(s), MAP kinase



             MARAMA          Mid Atlantic Regional Air Management Association



             MATCH            Model of Atmospheric Transport and Chemistry



             max                maximum



             MBP               major basic protein



             MCAPS             Medicare Air Pollution Study
December 2009
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             Mch                methacholine

             MCN               mixed carbon nanoparticle

             MCP-1              monocyte chemoattractant protein 1

             MC V               mean corpuscular volume

             MD                 mineral dust

             MDA               malondialdehyde

             MDCT              multidetector computed tomography

             ME                 Multilinear Engine

             MEE               mass extinction efficiency

             MEF               maximal expiratory flow

             MEF50              maximum expiratory flow rate at 50% of vital capacity

             MeHg              methyl mercury

             MENTOR           Modeling Environment for Total Risk Studies

             MEP               motorcycle exhaust particulate(s)

             MEPE              motorcycle exhaust particulate extract (particle-free)

             MESA              Multi-Ethnic Study  of Atherosclerosis

             MFFSR             multifilter rotating shadowband radiometer

             mg/m3              milligrams per cubic meter

             Mg                 magnesium

             MI                 myocardial infarction

             MIROC3 .x          Model for Interdisciplinary Research on Climate

             MILAGRO          Megacity Initiative: Local and Global Research Observations, study
                                 of air pollution in Mexico City

             min                 minute(s), minimum

             MINOS             MPI Mediterranean INtensive Oxidant Study

             MIP-2              macrophage inflammatory protein-2

             MIRAGE            Megacities Impact on Regional and Global Environment program

             MIS                mullerian inhibiting substance

             MISR              Multi-angle Imaging SpectroRadiometer

             Mm                 megameter

             Mm"1               inverse megameter

             MM                monocyte-derived macrophages

             MM5               mesoscale model

             MMAD             mass median aerodynamic diameter

             MMD              mass median diameter

             MMEF              maximal mid-expiratory flow
December 2009
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             mmHg              millimeters of mercury



             MMP               mitochondria membrane potential



             MMP(2,9)           matrix metalloproteinase (2, or 9)



             MMT               million metric tons



             Mn                 manganese



             MN                 micronuclei



             MnSO4             manganese sulfate



             MnSOD             manganese superoxide dismutase



             MnTBAP           manganese tetrakis (4-benzoic acid) porphyrin



             mo                 month



             MOA               mode(s) of action



             MODIS             MODerate resolution Imaging Spectroradiometer



             MOUDI             Micro-Orifice Uniform Deposit Impactor



             MOZART           MOdel for Ozone and Related chemical Tracers



             MP                 mid polar, myelopeptide



             MFC               mean platelet component



             MPF               median power frequency



             MPG               N-(2-mercaptopropionyl) glycine



             MPI                Max Planck Institute for Meteorology



             MPLNET           Micro-Pulse Lidar Network



             MPO               myeloperoxidase



             MPPD              Multiple-Path Particle Dosimetry model



             MPV               mean platelet volume



             MRI                Meteorological Research Institute



             MRI-CGCM         MRI coupled general circulation model



             mRNA             messenger RNA



             MRPO              Midwest Regional Planning Organization



             ms                 millisecond



             MSA               metropolitan statistical area



             MSH               melanocyte stimulating hormone



             MSHA             Mount St. Helen ash



             MSU               monosodium urate crystals



             MT                 metric ton



             MTHFR             methylenetetrahydrofolate reductase



             MTT               methyl thiazol tetrazolium
December 2009
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             MV                motor vehicle

             MWNT             multiple-wall nanotube

             M/Z                mass-to-charge ratio

             N                  nitrogen

             N2O                nitrous oxide

             Na                 sodium

             Na2SO4             sodium sulfate

             NAAQS            National Ambient Air Quality Standards

             NAC               N-acetylcysteine, a thiol antioxidant

             NaCl               sodium chloride

             NADPH            reduced form of nicotinamide adenine dinucleotide phosphate

             NAG               N-acetyl-p-D-glucosaminidase

             Na,K-ATPase        sodium-potassium adenosine triphosphatase

             NAMS              National Ambient Monitoring Stations

             NaN3               sodium azide

             NaNO3              sodium nitrate

             nano-BAM          low pressure-drop ultrafine particle impactor coupled with a Beta
                                 Attenuation Monitor

             NAPAP             National Acid Precipitation Assessment Program

             NAPCA            National Air Pollution Control Administration

             NAS               National Academy of Sciences

             NASA              U. S. National Aeronautics and Space Administration

             NASDA            National Space Development Agency, Japan

             NATA              U. S. EPA's National Air Toxics Assessment

             2-NB               2-nitrobenzanthrone

             NC                 total (particle) number concentration

             NC AR              National Center for Atmospheric Research

             NCC-MPSP         negatively charged carboxylate-modified polystyrene particle(s)

             NCD               Normal Chow Diet

             NCEA              National Center for Environmental Assessment

             NCHS              National Center for Health Statistics

             NCICAS            National Cooperative Inner-City Asthma Study

             NCore              National Core

             Nd                 drop number concentration

             Nd: YAG            neodymium-doped yttrium aluminum garnet laser

             NDDN              National Dry Deposition Network
December 2009
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             NEAQS             NOAA New England Air Quality Study



             NEI                National Emissions Inventory



             NESCAUM         Northeast States for Coordinated Air Use Management



             NET                National Emissions Trends database



             NFicB               nuclear factor kappa-B



             NG                 neutrophil granulocytes



             NH                 northern hemisphere



             NH3                ammonia



             NH4+               ammonium ion



             NH4NO3            ammonium nitrate



             (NH4)2SO4          ammonium sulfate



             NHANES           National Health and Nutrition Examination Survey



             NHBE(C)            normal human bronchial epithelial cells



             NHPAE             normal human pulmonary artery endothelial cells



             NHS                Nurses' Health Study



             Ni                  nickel



             NIOSH             National Institute for Occupational Safety and Health



             NIST               National Institute of Standards and Technology



             NMHC             non-methane volatile hydrocarbon



             NMMAPS          U. S. National Morbidity, Mortality, and Air Pollution Study



             NO                 nitric oxide



             NO2, NO2           nitrogen dioxide, nitrogen dioxide radical



             NO3~               nitrate



             NOAA             National Oceanic and Atmospheric Administration



             NOAEL             no observed adverse effect level



             NOS                nitric oxide synthase



             NOS3               nitric oxide synthase 3



             NOx                nitrogen oxides, oxides of nitrogen (NO + NO2)



             NP                 National Park



             NPM               non-blowing PM2 5



             NPOESS            National Polar-orbiting Operational Environment Satellite System



             NFS                National Park Service, U.S. Department of the Interior



             NR                 not reported



             NR5A1             nuclear receptor subfamily 5, group A, member 1



             NRC                National Research Council
December 2009
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             NRPB

             NSA

             NT

             NWS

             NYHA

             O

             O2

             03

             OAQPS

             OC

             OCM

             OE

             OGG1

             OH, OH'

             8-OHdG

             OM

             OMI

             OMM

             OR

             OSM

             OSPM

             OVA

             oxLDL

             8-oxodG

             ox-PAPC

             P450

             P450cl7

             P450scc

             P90

             P

             P

             PA


             PAF

             PAH

             PAI
National Radiological Protection Board

North Slope Alaska

neurotrophin, nitrotyrosine

National Weather Service

New York Heart Association

oxygen

molecular oxygen

ozone

Office of Air Quality Planning and Standards

organic carbon

organic carbon mass

organic extracts

8 oxo-guanine repair enzyme

hydroxyl group, hydroxyl radical

8-hydroxydeoxyguanosine

organic matter

Ozone Monitoring Instrument

organic molecular marker

odds ratio(s)

oncostatin M, a cytokine

Operational Street Pollution Model

ovalbumin

oxidation of LDL, marker of oxidative stress

8-oxo-7-hydrodeoxyguanosine

oxidized l-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine

cytochrome P450

cytochrome P450 17-a-hydroxylase

cytochrome P450 cholesterol side chain cleavage enzyme

90th percentile; Printex 90

probability  value

phosphorus

photoacoustic analyzer, physical activity, plasminogen activator,
pulmonary arterial, alveolar pressure

platelet-activating factor

polycyclic aromatic hydrocarbon(s)

plasminogen activator inhibitor, (e.g. PAI-1)
December 2009
                    Ixxv

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             PALMS             NOAA Particle Analysis by Laser Mass Spectrometry instrument

             PAMCHAR         Chemical and Biological Characterisation of Ambient Air Coarse,
                                 Fine, and Ultrafine Particles for Human Health Risk Assessment in
                                 Europe

             PAMS              Photochemical Assessment Monitoring Stations network

             PAR                photosynthetically active radiation

             PAR(s)             Pulmonary Artery Rings

             PARASOL          Polarization and Directionality of the Earth's Reflectances, coupled
                                 with observations from a Lidar, a CNES satellite

             PARP              poly(ADP-ribose) polymerase

             PAS                Periodic Acid Schiff stain

             Pb                  lead

             207Pb               lead-207

             PBDE              polybrominated diphenyl ether

             PEL                planetary boundary layer

             PBMC              peripheral blood mononuclear cell

             PBMM             peripheral blood monocyte-derived macrophages

             PBP                primary biological particle(s)

             PBS                phosphate buffered saline

             PC                 synthetic carboxylate-modified particles

             PCA                principal component analysis

             PCA-MPSP         positively-charged amine modified polystyrene particle

             PCB                polychlorinated biphenyl(s)

             PCDD              polychlorinated dibenzo-p-dioxin

             PCIS               Personal Cascade Impactor Sampler

             PCM               NCAR Parallel Climate Model

             PCPSP             positively charged polystyrene particle

             PCR                polymerase chain reaction

             PDF                probability distribution functions

             pDR                personal DataRam

             PE                 post exposure, post exercise, phenylephrine

             PEACE             Pollution Effects on Asthmatic Children in Europe study

             PEC                particulate elemental carbon

             PEC AM-1           platelet endothelial cell adhesion molecule 1

             PEF                peak expiratory flow (L/min)

             PEFR              peak expiratory flow rate
December 2009
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              PEFT

              PEM

              PEM-West

              Penh

              Per

              PESA

              PFDE

              PGE2

              PGI2

              Phe

              PI

              PICT

              PILS

              PILS-IC

              PIXE

              PKA

              PLS

              PM

              PMx
              PMx-y




              FMo.i


              PM2.5


              PM10


              PM10.2.5
              PMA

              PMF
time to peak flow

personal exposure monitor

NASA Pacific Exploratory Missions in the western Pacific

enhanced pause

perylene

particle elastic scattering analysis

particle free diesel exhaust

prostaglandin E2

prostacyclin

phenanthrene

post instillation, posterior interval, pulmonary inflammation

pollution-induced community tolerance

Particle Into Liquid Sampler

Particle Into Liquid Sampler-Ion Chromatography

Particle Induced X-ray Emission

protein kinase A

partial least squares, projection to latent structures

particulate matter

particulate matter of a specific size range. X refers to the diameter at
which the sampler collects 50% of the particles and rejects 50% of the
particles. Collection efficiency increases for particles with smaller
diameters and decreases for particles with larger diameters.  The
variation of collection efficiency with size is given by a collection
efficiency curve. The definition of PMx is frequently abbreviated as
"particles with a nominal mean aerodynamic diameter less than or
equal to x |im.

particulate matter with a nominal mean diameter greater than x |im
and less than y |im where x and y are the numeric mean aerodynamic
or mobility diameters (|im).

particulate matter with a nominal mean mobility diameter less than or
equal to 0.1 |im (referred to as ultrafine PM)

particulate matter with a nominal mean aerodynamic diameter less
than or equal to 2.5  |im (referred to as fine PM)

particulate matter with a nominal mean aerodynamic diameter less
than or equal to 10 |im

particulate matter with a nominal mean aerodynamic diameter greater
than 2.5 [im and less than or equal to 10 [im (referred to as thoracic
coarse particulate matter or the course fraction of PM10)
Concentration may be measured with a dichotomous sampler or
calculated as the difference between measured PMi0 and measured
PM25 concentrations.

phorbol 12-myristate 13-acetate

particulate matter filtrate, positive  matrix factorization
December 2009
                    Ixxvii

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             PM-HD

             PM-LD

             PMN

             PN

             PNC

             PND, pnd

             PNMD

             PNN


             pNNSO


             PNNL

             pNO3

             POA

             POC

             POLDER

             POM

             POP

             PP

             PP

             ppb

             PPFL

             ppm

             ppt

             PRB

             PRE

             PRELC

             PRIDE

             PS

             PSAS

             PSO

             pS04

             PSS

             PSU

             PT

             PIT
participate matter at high concentration

participate matter at low concentration

polymorphonuclear leukocytes

particle number

particle number concentration, particle number count

 post-natal day

particle number median diameter

proportion of interval differences of successive normal-beat intervals
inEKG

proportion of interval differences of successive normal-beat intervals
greater than 50 ms in an EKG

Pacific Northwest National Laboratory

particulate nitrate

primary organic aerosol

particulate organic carbon

POLarization and Directionality of the Earth's Reflectance

particulate organic matter

persistent organic pollutant

particle density

pulse pressure

parts per billion

percent predicted lung function

parts per million

parts per trillion

policy-relevant background

AeroCom Experiment

Primary Rat Epithelial Lung Cells

Puerto Rico Dust Experiment

public school

The French National Program on Air Pollution Health Effects

Public Service Company  of Oklahoma

particulate sulfate

physiologic saline solution

Pennsylvania State University

prothrombin time

partial thomboplastin time
December 2009
                   Ixxviii

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             PTV                programmable temperature vaporization

             PVD                peripheral vascular disease

             Pyr                 pyrene

             <2                   cardiac output

             Q                   coronary flow of the heart

             QAI                Q A interval

             QBQ                backup quartz-fiber filter behind a quartz-fiber filter

             QEEG               quantitative electroencephalography

             Qext                the extinction coefficient (a function of particle size distribution and
                                  refractive index)

             r                    correlation coefficient

             R2                  coefficient of determination

             RAIN               Regional Aerosol Intensive Network

             RAMS              real-time total ambient mass sampler

             RANTES            regulated upon activation, normal T cell expressed and secreted

             RAPS/RAMS        Regional Air Pollution Study / Regional Air Monitoring Study

             RAR                rapidly activating receptor(s)

             RASMC             rat aortic smooth muscle cells

             RAW 264.7          mouse macrophage cell line

             RBC                red blood cell

             RD                 respiratory disease

             REALM             Regional East Atmospheric Lidar Mesonet

             RF                  radiative forcing(s)

             reff                  particle effective radius

             RFL                Fetal Lung Fibroblasts

             RH                 relative humidity

             RHMVE             rat heart micro-vessel endothelial cell

             RHR                Regional Haze Rule

             RLF                rat lung fibroblasts

             RMC                rat cardiomyocyte(s)

             RME                rapeseed oil methyl ester

             RMSSD             root mean squared differences of successive normal-beat to normal-
                                  beat (NN or RR) time intervals between each QRS complex in the
                                  EKG

             RMV                respiratory minute volume

             RNA                ribonucleic acid
December 2009
Ixxix

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             RNS

             RO

             ROCK

             ROFA

             ROFA-L

             ROI

             ROS

             RPO

             RR


             RS

             RSV

             RTI

             RTM

             RTF

             RV

             RVCFB

             RVCM


             a

             la

             °g

             s

             S

             SAB

             SAFARI

             SAGE

             SALIA


             SAM

             SAMUM

             SAP2.3

             Sb

             SB

             SBL

             SBP
reactive nitrogen species

residual oil

rho associated kinase

residual oil fly ash (particles)

residual oil fly ash leachate

reactive oxygen intermediates

reactive oxygen species

Regional Planning Organizations

risk ratio, relative risk, normal-to-normal (NN or RR) time interval
between each QRS complex in the EKG

resuspended soil

respiratory syncytial virus

respiratory tract infection

Radiative Transfer Model

Research Triangle Park, North Carolina

right ventricular

right ventricular cardio fibroblasts

right ventricular cardiomyopathy, rat ventricular cardiomyocytes,
reduced volume culture medium

sigma, standard deviation

one sigma; one standard deviation

sigma-g; geometric standard deviation

second

sulfur

(EPA) Science Advisory Board

South African Fire-Atmosphere Research Initiative

Stratospheric Aerosol and Gas Experiment

German study on the Influence of Air Pollution on Lung Function,
Inflammation, and Aging

Stratospheric Aerosol Measurement

Saharan Mineral Dust Experiment

Synthesis and Assessment Product 2.3

antimony

strand breaks

stable boundary layer

systolic blood pressure
December 2009
                    Ixxx

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             Sc                  scandium

             SC                 summer curbside particles

             SCAB              California South Coast Air Basin

             SCAR              Smoke/Sulfates, Clouds and Radiation

             SCARPOL          Swiss Study on Childhood Allergy and Respiratory Symptoms with
                                 Respect to Air Pollution

             sCD40L             soluble CD40 ligand

             SCE                sister chromatid exchange

             SCS                Harvard Six Cities Study

             SD                 standard deviation; Sprague-Dawley rat

             SDANN5           standard deviation of the average of normal to normal (N:N) intervals
                                 in all 5-min intervals in a 24-h period

             SDNN              standard deviation normal-to-normal (NN or RR) time interval
                                 between each QRS complex in the EKG

             SDNN24HR         standard deviation of the average of all normal to normal intervals in
                                 a 24-h period

             Se                  selenium

             se                  standard error

             SEARCH           Southeastern Aerosol Research and Characterization

             sem                standard error of mean

             SEM               scanning electron microscopy

             SES                socioeconomic status, sample equilibration system

             SF-1                steroidogenic factor -1

             SF-UFID           suspension, particle free ultrafine industrial exhaust

             SGA               small for gestational age

             sGC                soluble guanylate cyclase

             SGP                Southern Great Plains

             -SH                sulfhydryl group

             SH                 Mount Saint Helen's ash

             SH, SHR           spontaneously hypertensive disease model rat

             SHADE             Saharan Dust Experiment

             SHEDS             Stochastic Human Exposure and Dose Simulation model

             Si                  silicon

             sIC AM-1           soluble intercellular adhesion molecule

             SIDS               sudden infant death syndrome

             SiO2                silicone dioxide

             SIPS               State Implementation Plan
December 2009
Ixxxi

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              SJV                 San Joaquin Valley

              SLAMS             State and Local Air Monitoring Stations

              SME                soybean oil methyl ester

              SMOCC             Smoke Aerosols, Clouds, Rainfall and Climate

              SMOKE             Spare-Matrix Operator Kernel Emissions system

              SMPS               scanning mobility particle sizer

              SMPS-APS          scanning mobility particle sizer- aerodynamic particle sizer

              SMRA              small mesenteric rat arteries

              SNP                 single-nucleotide polymorphism,  sodium nitroprusside

              SNS                 sympathetic nervous system

              SO2                 sulfur dioxide

              SO3                 sulfur trioxide

              SO42~               sulfate

              SOA                secondary organic aerosol

              SOC                 semi-volatile organic compound

              SOD                superoxide dismutase

              SOPHIA             Study of Particulates and Health in Atlanta

              SOX                 sulfur oxides, oxides of sulfur

              SP                  surfactant protein (e.g., SPA, SPD)

              SPA                 surfactant protein A

              SPD                 surfactant protein D

              SPEW               Speciated Pollutant Emission Wizard

              SPG                 Southern Great Plains site

              SPM                suspended particulate matter

              SPPJNTARS         Spectral Radiation-Transport Model for Aerosol Species

              SRM-154b           NIST standard reference material 154b; (TiO2 Titanium dioxide)

              SRM1648           NIST standard reference material 1648; (urban particulate matter)

              SRM-1649           NIST standard reference material 1649 (Washington, D.C. urban air
                                  particulate matter, urban dust)

              SRM-1650           NIST standard reference material 1650 (diesel exhaust particulate
                                  matter)

              SRM-1879           NIST standard reference material 1859; (silicone dioxide, respirable
                                  cristobalite [respirable crystalline silica])

              SRM-2975           NIST standard reference material 2975 (diesel exhaust particulate
                                  matter)

              s-ROFA             soluble portion of residual oil fly  ash

              SS                  secondary sulfate, sea salt
December 2009
Ixxxii

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             SSA




             SSR




             SST




             STEM




             STN




             STP




             STZ




             SUB




             SURFRAD




             SVA




             sVCAM-1




             SVEB




             SWNT




             SXRF




             SZA




             T




             T




             TAR




             TARC




             TARFOX




             TAT




             TB




             TEA




             TBAP




             TEARS




             TBQ




                Tc




                Tc-DMTA




                Tc-DTPA




             Too



             TD




             TD-GC/MS




             TEAC




             TEOM




             TexAQS
99m.





99m.





99M.
single-scattering albedo



standardized sex ratio



sea surface temperature



Sulfur / Sulfate Transport Eulerian Model



EPA Speciation Trend Network



standard temperature and pressure



Streptozotocin



summer urban background particles



NOAA GMD Surface Radiation network



supraventricular arrhythmia



soluble vascular adhesion molecule 1



supraventricular ectopic beats



singlewalled nanotube



Synchroton X-ray fluorescence



solar zenith angle



photochemical lifetime



body temperature



IPCC 3rd Assessment Report



thymus and activation-regulated chemokine



Tropospheric Aerosol Radiative Forcing Observational Experiment



thrombin-anti-thrombin complexes



tracheobronchial



thiobarbituric acid



tetrakis(4-benzoic acid) porphyrin



thiobarbituric acid reactive substances



backup quartz-fiber filter behind a Teflon-membrane filter



Technetium-99m



99MTc Dynamic mechanical thermal analysis



99MTc-diethylenetriaminepentaacetic acid



core  temperature



thermal desorption, tire debris extracted in methanol



thermal desorption-gas chromatography/mass spectrometry



Trolox Equivalent Antioxidant Capacity assay



Tapered Element Oscillating Microbalance



Texas Air Quality Field Study
December 2009
                                       Ixxxiii

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             TF

             TFPI

             Tg

             TG

             TGF

             TGFP

             Th

             Thl

             Th2

             tHcy

             Ti

             TIA

             TiFe

             TIMP-2

             Ti02

             TK

             TM

             TM5

             TMTU

             TNF-a

             TOA

             TOP-SIMS

             TOMS

             TOT/GC


             TOYS

             tPA, t-PA

             TRACE

             TRP

             TRPV1

             TR-XRF

             TSA

             TSP

             TSS

             TVOC

             TWP
tissue factor

tissue factor pathway inhibitor

teragram

terminal ganglion (neurons)

transforming growth factor

P transforming growth factor

thorium

T helper cell type 1

T helper cell type 2

total homocysteine

titanium

transient ischemic attack

iron-loaded fine titanium oxide

tissue inhibitor of MMP

titanium dioxide

thymidine kinase

transition metals

Thematic Mapper, a sensor on LandsatS satellite

tetramethylthiourea

tumor necrosis factor alpha

top of the atmosphere

time-of-flight - secondary ion mass spectrometry

Total Ozone Mapping Spectrometer

thermal optical transmission analyzer coupled with gas
chromatography

TIROS-N Operational Vertical Sounder

tissue plasminogen activator

Transition Region and Coronal Explorer

transient receptor potential

transient receptor potential vanilloid-1 receptor

total reflection X-ray fluorescence

tricho statin A

total suspended particulate

WRAP Technical Support System website

total VOC

Tropical West Pacific island
December 2009
                   Ixxxiv

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             TXB2

             U

             UACR

             UAE2

             UAP

             UF

             UFAA

             HFC

             UfCB

             UFDG

             UFID

             UFP

             UFPM

             UFTiO2

             UIO

             U.K.

             UKMO

             ULAQ

             ULTRA


             UMI

             UNEP

             UP

             UPM

             UPSP

             URI

             URS

             U.S.

             U.S.C.

             UV

             V

             V, mV, \i

             VAQ

             VCAM-l

             Vd

             VEAPS
thromboxane B-2

uranium

urinary albumin / creatinine ratio

United Arab Emirates Unified Aerosol Experiment

urban ambient particle

ultrafine, uncertainty factor

ultrafine ambient air

ultrafine carbon

ultrafine carbon black

ultrafine diesel engine exhaust

ultrafine industrial exhaust

ultrafine particle

ultrafine particulate matter

ultrafine titanium dioxide

University of Oslo

United Kingdom

United Kingdom Meteorological Office

University of IL'Aquila.

Exposure and Risk Assessment for Fine and Ultrafine Particles in
Ambient Air

University of Michigan

United Nations Environmental Programme

urban particle

ultrafine particulate matter

unmodified polystyrene particle(s)

upper respiratory infection

upper respiratory symptoms

United States of America

U.S. Code

ultraviolet radiation

vanadium

volt, millivolt, microvolt

visual air quality

vascular adhesion molecule 1

deposition velocity

Vitamin E Atherosclerosis Progression Study
December 2009
                   Ixxxv

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             VEGF               vascular endothelial growth factor

             VIEWS              Visibility Information Exchange Web Site

             VISTAS             Visibility Improvement State and Tribal Association of the Southeast

             VOC                volatile organic compound

             VOSO4              vanadyl sulfate

             VPB                ventricular premature beat

             VR                  visual range

             VR1                 vanilloid receptor 1

             VSCC               very sharp cut cyclone

             VSMC               Vascular Smooth Muscle Cells

             VT                  tidal volume

             vWF                von Willebrand factor

             W                  Wilderness

             WACAP             Western Airborne Contaminates Assessment Project

             WBC                white blood cell(s)

             WC                 winter curbside particles

             WHI                Women's Health Initiative

             WHI OS             Women's Health Initiative Observational Study

             wk                  week(s)

             WKY                Wistar-Kyoto rat strain

             W/m2, W m"2         watts per square meter

             WMO               World Meteorological Organization

             Wnt                 wingless gene family

             WRAP               Western Regional Air Partnership

             WRF                Weather Research and Forecasting model

             WS                  wood smoke

             WSOC               water soluble organic carbon

             WUB                winter urban background particles

             XAD                polystyrene-divinyl benzene

             XPS                 X-ray photoelectron spectroscopy

             Y                   yttrium

             yr                   year

             Z                   radar reflectivity (measured in dBZ [decibels of Z, where Z represents
                                  the energy reflected back to the radar.])

             Zn                  zinc

             ZnO                 zinc oxide
December 2009
Ixxxvi

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             ZnS                 zinc sulfide



             ZnSO4               zinc sulfate



             Zr                   zirconium
December 2009                                        Ixxxvii

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                     Chapter  1. Introduction
      This Integrated Science Assessment (ISA) is a review, synthesis, and evaluation of the most
policy-relevant evidence, and communicates critical science judgments relevant to the National
Ambient Air Quality Standards (NAAQS) review. As such, the ISA forms the scientific foundation
for the review of the primary (health-based) and secondary (welfare-based) NAAQS for particulate
matter (PM). The ISA accurately reflects "the latest scientific knowledge useful in indicating the
kind and extent of identifiable effects on public health which may be expected from the presence of
[a] pollutant in ambient air" (42 U.S.C. 7408). Key  information and judgments formerly contained in
an Air Quality Criteria Document (AQCD) for PM are incorporated in this assessment. Additional
details of the pertinent  literature published since the last review, as well as selected older studies of
particular interest, are included in a series of annexes. This ISA thus serves to update and revise the
evaluation of the scientific evidence available at the time of the previous review of the NAAQS for
PM that was concluded in 2006.
      The Integrated Review Plan for the National Ambient Air Quality Standards for Paniculate
Matter identifies a series of policy-relevant questions that provide a framework for this assessment
of the scientific evidence (U.S. EPA, 2008, 157072). These questions frame the entire review of the
NAAQS for PM, and thus are informed by both science and policy considerations. The ISA
organizes and presents  the scientific evidence such that, when considered along with findings from
risk analyses and policy considerations, will help the EPA address these questions during the
NAAQS review for PM. In  evaluating the health evidence, the focus of this assessment will be on
scientific evidence that is most relevant to the following questions that have been taken directly from
the Integrated Review Plan:

       •   Has new information altered the body of scientific support for the occurrence of health
           effects following short- and/or long-term exposure to levels of fine and thoracic coarse
           particles found in the ambient air?

       •   Has new information altered conclusions from previous reviews regarding the
           plausibility of adverse health effects associated with exposures to PM2.5, PMi0, PMi0_2.5,
           or alternative PM indicators that might be considered?

       •   What evidence is available from recent studies focused on specific size fractions,
           chemical components, sources, or environments (e.g., urban and non-urban areas) of PM
           to inform our understanding of the nature of PM exposures that are linked to various
           health outcomes?

       •   To what extent is key scientific evidence becoming available to improve our
           understanding of the health effects associated with various time periods of PM
           exposures,  including not only short-term (daily or multi-day) and chronic (months to
           years) exposures, but also peak PM exposures (<24 hours)? To what extent is critical
           research becoming available that could improve our understanding of the relationship
           between various health endpoints and different lag periods (e.g., <1 day, single day,
           multi-day distributed lags)?

       •   What data are available to  improve our understanding of spatial and/or temporal
           heterogeneity of PM exposures considering different size fractions and/or components?

       •   At what levels of PM exposure do health effects of concern occur? Is there evidence for
           the occurrence of adverse health effects at levels of PM lower than those observed
           previously? If so, at what levels and what are the important uncertainties associated with
Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
December 2009                                  1-1

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           that evidence? What is the nature of the dose-response relationships of PM for the
           various health effects evaluated?

       •   What evidence is available linking particle number concentration with adverse health
           effects of UF particles?

       •   Do risk/exposure estimates suggest that exposures of concern for PM-induced health
           effects will occur with current ambient levels of PM or with levels that just meet the
           current standards? If so, are these risks/exposures of sufficient magnitude such that the
           health effects might reasonably be judged to be important from a public health
           perspective? What are the important uncertainties associated with these risk/exposure
           estimates?

       •   To what extent is key evidence becoming available that could inform our understanding
           of subpopulations that are particularly sensitive or vulnerable to PM exposures? In the
           last review, sensitive or vulnerable subpopulations that appeared to be at greater risk for
           PM-related effects included individuals with pre-existing heart and lung diseases, older
           adults, and children. Has new evidence become available to suggest additional sensitive
           subpopulations should be given increased focus in this review (e.g., fetuses, neonates,
           genetically susceptible subpopulations)?

       •   To what extent is key evidence becoming available to inform our understanding of
           populations that  are particularly vulnerable to PM exposures? Specifically, is there new
           or emerging evidence to inform our understanding of geographical, spatial, SES, and
           environmental justice  considerations?

       •   To what extent have important uncertainties identified in the last review been reduced
           and/or have new uncertainties emerged?

       •   To what extent is new information available to inform our understanding of non-PM-
           exposure factors that might influence the associations between PM levels and health
           effects being considered (e.g., weather-related factors; behavioral factors such as
           heating/air conditioning use; driving patterns; and time-activity patterns)?

      In evaluating evidence on welfare effects of PM, the focus will be on evidence that can help
inform these questions from the Integrated Review Plan:

       •   What new evidence is available on the relationship between PM mass/size fraction
           and/or specific PM components and visibility impairment and climate-related and other
           welfare effects?

       •   To what extent has key scientific evidence now become available to improve our
           understanding of the nature and magnitude of visibility, climate, and ecosystem
           responses to PM and the variability associated with those responses (including ecosystem
           type, climatic conditions, environmental effects and interactions with other
           environmental factors and pollutants)?

       •   Do the evidence, the air quality  assessment, and the risk/exposure assessment provide
           support for considering alternative averaging times?

       •   At what levels of ambient PM do visibility impairment and/or environmental effects of
           concern occur? Is there evidence for the occurrence of adverse visibility and other
           welfare-related effects at levels of PM lower than those observed previously? If so, at
           what levels and what are the important uncertainties associated with the evidence?

       •   Do the analyses suggest that PM-induced visibility impairment and/or other welfare-
           effects will occur with current ambient levels of PM or with levels that just meet the
           current standards? If so, are these effects of sufficient magnitude and/or frequency such
December 2009                                   1-2

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           that these effects might reasonably be judged to be important from a public welfare
           perspective? What are the uncertainties associated with these estimates?

           What new evidence and/or techniques are available to quantify the benefits of improved
           visibility and/or other welfare-related effects?

           To what extent have important uncertainties identified in the last review been reduced
           and/or have new uncertainties emerged?
1.1.   Legislative  Requirements
      Two sections of the United States (U.S.) Clean Air Act (CAA, the Act) govern the
establishment and revision of the NAAQS. Section 108 of the Act (42 U.S.C. 7408) directs the
Administrator to identify and list "air pollutants" that "in his judgment, may reasonably be
anticipated to endanger public health and welfare" and whose "presence... in the ambient air results
from numerous or diverse mobile or stationary sources" and to issue air quality criteria for those that
are listed (42 U.S.C. 7408). Air quality criteria are intended to "accurately reflect the latest scientific
knowledge useful in indicating the kind and extent of identifiable effects on  public health or welfare
which may be expected from the presence of [a] pollutant in ambient air..."  42 U.S.C. 7408(b).
      Section 109 of the Act (42 U.S.C. 7409) directs the Administrator to propose and promulgate
"primary" and  "secondary" NAAQS for pollutants listed under Section 108. 42 U.S.C. 7409(a).
Section 109(b)(l) defines a primary standard as one "the attainment and maintenance of which in the
judgment of the Administrator, based on such criteria and allowing an adequate margin of safety, are
requisite to protect the public health."! 42 U.S.C. 7409(b)(l). A secondary standard, as defined in
Section 109(b)(2), must "specify a level of air quality the attainment and maintenance of which, in
the judgment of the Administrator, based  on such criteria, is required to protect the public welfare
from any known or anticipated adverse effects associated with the presence of [the] pollutant in the
ambient air."2 42 U.S.C. 7409(b)(2).
      The requirement that primary standards include an adequate margin of safety was intended to
address uncertainties associated with inconclusive scientific  and technical information available at
the time of standard setting. It was also intended to provide a reasonable degree of protection against
hazards that research has not yet identified. See Lead Industries Association v. EPA, 647 F.2d 1130,
1154 (D.C. Cir 1980), cert, denied, 449 U.S.  1042 (\9%Q); American Petroleum Institute v. Costle,
665 F.2d 1176, 1186 (D.C. Cir. 1981), cert, denied, 455 U.S.  1034 (1982); American Farm Bureau
Federation v. EPA, 559 F. 3d 512, 533 (D.C. Cir. 2009).  Both kinds of uncertainties are components
of the risk associated with pollution at levels below those at which human health effects can be said
to occur with reasonable scientific certainty. Thus, in selecting primary standards that include an
adequate margin of safety, the Administrator is seeking not only to prevent pollution levels that have
been demonstrated to be harmful, but also to prevent lower pollutant levels that may pose an
unacceptable risk of harm, even if the risk is not precisely identified as to nature or degree.
      In selecting a margin of safety, the  EPA considers such factors as the nature and severity of the
health effects involved, the size of the sensitive population(s) at risk, and the kind and degree of the
uncertainties that must be addressed. The selection of any particular approach to providing an
adequate margin of safety is a policy  choice left specifically  to the Administrator's judgment. See
Lead Industries Association v. EPA, supra, 647 F.2d  1161-62.
      In setting standards that are "requisite" to protect public health and welfare, as provided in
Section 109(b), the Administrator's task is to establish standards that are neither more nor less
1 The legislative history of Section 109 indicates that a primary standard is to be set at "the maximum permissible ambient air
 level... which will protect the health of any [sensitive] group of the population," and that for this purpose "reference should be made to a
 representative sample of persons comprising the sensitive group rather than to a single person in such a group" [S. Rep. No. 91-1196,
 91st Cong., 2d Sess. 10 (1970)].

2 Welfare effects as defined in Section 302(h) [42 U.S.C. 7602(h)] include, but are not limited to, "effects on soils, water, crops, vegetation,
 man-made materials, animals, wildlife, weather, visibility and climate, damage to and deterioration of property, and hazards to
 transportation, as well as effects on economic values and on personal comfort and well-being."
December 2009                                    1-3

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stringent than necessary. In so doing, EPA may not consider the costs of implementing the standards.
See generally Whitman v. American Trucking Associations, 531 U.S. 457, 465-472, 475-76 (2001).
      Section 109(d)(l) requires that "not later than December 31, 1980, and at 5-yr
intervals thereafter, the Administrator shall complete a thorough review of the criteria
published under Section 108 and the national ambient air quality standards... and shall make such
revisions in such criteria and standards and promulgate such new standards as may be
appropriate... " 42 U.S.C. 7409(d)(l). Section 109(d)(2) requires that an independent scientific
review... committee "shall complete a review of the criteria and the national primary  and secondary
ambient air quality standards... and shall recommend to the Administrator any new standards and
revisions of existing criteria and standards as may be appropriate..." 42 U.S.C. 7409(d)(2).  Since the
early 1980s, this independent review function has been performed by the Clean Air Scientific
Advisory Committee (CASAC).



1.2.  History  of Reviews of the NAAQS for PM

      PM is the generic term for a broad class of chemically and physically diverse substances that
exist as discrete particles (liquid droplets or solids) over a wide range of sizes. Particles originate
from a variety of anthropogenic stationary and mobile sources, as well  as from natural sources.
Particles may be emitted directly or formed in the atmosphere by transformations of gaseous
emissions such as sulfur oxides (SOX), nitrogen oxides  (NOX), and volatile organic compounds
(VOC). The chemical and physical properties of PM vary greatly with time,  region, meteorology,
and source category, thus complicating the assessment of health and welfare effects. Table 1-1
summarizes the NAAQS that have been promulgated for PM to date. These reviews are briefly
described below, and further details are provided in the Integrated Review Plan (U.S. EPA, 2008,
157072).
      EPA first  established NAAQS for PM in 1971 (36 FR 8186, April 30,  1971), based on the
original criteria document (NAPCA, 1969, 014684). The reference method specified  for determining
attainment of the original standards was the high-volume sampler, which collects PM up to  a
nominal size of 25-45 micrometers ((irn) (referred to as total suspended particulates [TSP]). The
primary standards (measured by the indicator TSP) were 260 (ig/m3, 24-h avg, not to be exceeded
more than once  per year, and 75 (ig/m3, annual geometric mean. The secondary standard was
150 (ig/m3, 24-h avg, not to be exceeded more than once per year. In October 1979 (44 FR 56730,
October 2, 1979), EPA announced the first periodic review of the air quality  criteria and NAAQS for
PM, and significant revisions to the original standards were promulgated in 1987 (52 FR 24634,
July 1, 1987). In that decision,  EPA changed the indicator for particles from TSP to PMi0, the latter
including particles with a mean aerodynamic diameter1 < 10 (im, which delineated that subset of
inhalable particles small enough to penetrate to  the thoracic region (including the tracheobronchial
and alveolar regions) of the respiratory tract (referred to as thoracic particles). EPA also revised the
level and form of the primary standards by (1) replacing the 24-h TSP standard with a 24-h  PMi0
standard of 150 (ig/m with no more than one expected exceedence per year; and (2) replacing the
annual TSP standard with a PMi0 standard of 50 (ig/m3, annual arithmetic mean, averaged over 3 yr.
1 The more precise term is 50% cut point or 50% diameter (d50). This is the aerodynamic particle diameter for which the efficiency of
 particle collection is 50%. Larger particles are not excluded altogether, but are collected with substantially decreasing efficiency and
 smaller particles are collected with increasing (up to 100%) efficiency.
December 2009                                  1-4

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Table 1-1.    Summary of NAAQS promulgated for PM, 1971-2006.
Year (Final Rule) Indicator
TSP (Total
1971 (36 FR 81 86) Suspended
Particulates)
1987 (52 FR 24634) PM10
PM25
1997 (62 FR 38652)
Avg Time Level
94 h 260 pg/m3 (primary)
^4n 1 50 pg/m3 (secondary)
Annual 75 pg/m3 (primary)
24 h 150 pg/m3
Annual 50 pg/m3
24 h 65 pg/m3
Annual 15 pg/m3
o/i h -icn i i,wm3
Form
Not to be exceeded more than once per yr
Annual geometric mean
Not to be exceeded more than once per yr on average over a 3-yr period
Annual arithmetic mean, averaged over 3 yr
98th percentile, averaged over 3 yr
Annual arithmetic mean, averaged over 3 yr1
Initially promulgated 99th percentile, averaged over 3 yr; when 1997 standards
               PM,r
                            24 h
                                    150 pg/m
                         were vacated in 1999, the form of 1987 standards remained in place (not to be
                         exceeded more than once per yr on average over a 3-yr period)
                            Annual    50 pg/m
                         Annual arithmetic mean, averaged over 3 yr
2006 (71 FR 61144)
               PM25
                            24 h
                                                     98th percentile, averaged over 3 yr
Annual
        15 pg/rri
Annual arithmetic mean, averaged over 3 yr
               PM,,
                            24 h
        150 pg/m3
Not to be exceeded more than once per yr on average over a 3-yr period
Note: When not specified, primary and secondary standards are identical.


       The secondary standard was revised by replacing it with 24-h and annual standards identical in
all respects to the primary standards. The revisions also included a new reference method for the
measurement of PMi0 in the ambient air and rules for determining attainment of the new standards.
On judicial review, the revised standards were upheld in all respects. See Natural Resources Defense
Council v. Administrator, 902 F. 2d 962 (D.C. Cir. 1990),  cert, denied, 498 U.S.  1082 (1991).
       In April 1994, EPA announced its plans for the second periodic review of the air quality
criteria and NAAQS for PM,  and promulgated significant revisions to the NAAQS in  1997 (62 FR
38652, July 18, 1997). In that decision, EPA revised the PM NAAQS in several respects. Most
significantly, EPA determined that the fine and coarse3  fractions of PM10 should be considered
separately. The Administrator's decision to modify the  standards was based on evidence that serious
health effects were associated with short- and long-term exposure to fine particles in areas that met
the existing PMi0 standards. EPA accordingly added new standards, using PM2.5 as the indicator for
fine particles (with PM2.5 referring to particles with a nominal mean aerodynamic diameter
< 2.5 (im), and PMi0 as the  indicator for thoracic coarse particles or coarse-fraction particles
(generally including particles with a nominal mean aerodynamic diameter >2.5 (im and < 10 (im, or
PMio_2.5). The EPA established two new PM2.5 standards: an annual standard of 15 (ig/m3, based on
the 3-yr avg of annual arithmetic mean PM25 concentrations from single or multiple
community-oriented monitors; and a 24-h standard of 65 (ig/m3, based on the 3-yr avg of the 98th
percentile of 24-h PM2.5 concentrations at each population-oriented monitor within an area. Also,
EPA established a new reference method for measuring PM2 5 in the ambient air  and adopted
protocols for determining attainment of the new standards. To continue to address thoracic coarse
particles, EPA retained the annual PMi0 standard, while revising the form, but not the level, of the
1 The level of the 1997 annual PM2.5 standard was to be compared to measurements made at the community-oriented monitoring site
 recording the highest level, or, if specific constraints were met, measurements from multiple community-oriented monitoring sites could
 be averaged ("spatial averaging"). This approach was judged to be consistent with the short-term epidemiologic studies on which the
 annual PM2.5 standard was primarily based, in which air quality data were generally averaged across multiple monitors in an area or were
 taken from a single monitor that was selected to represent community-wide exposures, not localized "hot spots" (62 FR 38672). These
 criteria and constraints were intended to ensure that spatial averaging would not result in inequities in the level of protection afforded by
 the PM2.5 standards. Community-oriented monitoring sites were specified to be consistent with the intent that a spatially averaged annual
 standard provide protection for persons living in smaller communities, as well as those in larger  population centers.

 In the revisions to the PM NAAQS finalized in 2006, EPA tightened the constraints on the spatial averaging criteria by further limiting
 the conditions under which some areas may average measurements from multiple community-oriented monitors to determine compliance
 (71 FR 61165-61167, October 17, 2006).

3 See definitions of "fine" and "coarse" particles in Section 3.2.
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24-h PM10 standard to be based on the 99th percentile of 24-h PM10 concentrations at each monitor
in an area. The EPA revised the secondary standards by making them identical in all respects to the
primary standards.
      Following promulgation of the 1997 PM NAAQS, petitions for review were filed by a large
number of parties, addressing a broad range of issues. In May 1999, a three-judge panel of the U.S.
Court of Appeals for the District of Columbia Circuit issued an initial decision that upheld EPA's
decision to establish fine particle standards, holding that "the growing empirical evidence
demonstrating a relationship between fine particle pollution and adverse health effects amply
justifies establishment of new fine particle standards. "American Trucking Associations v. EPA (175
F. 3d 1027, 1055-56 (D.C. Cir. 1999); rehearing granted in part and denied in part, 195 F. 3d 4 (D.C.
Cir. 1999), affirmed in part and reversed in part, Whitman v. American Trucking Associations 531
U.S. 457 (2001). The panel also found "ample support" for EPA's decision to regulate coarse particle
pollution, but vacated the 1997 PMi0 standards, concluding that EPA had not provided a reasonable
explanation justifying use of PMi0 as an indicator for coarse particles (175 F. 3d at 1054-55).
Pursuant to the court's decision, EPA removed the vacated 1997 PMi0 standards from the Code of
Federal Regulations. The pre-existing 1987 PMi0 standards remained in place (65 FR 80776,
December 22, 2000). The Court also upheld EPA's determination not to establish more stringent
secondary standards for fine particles to address effects on visibility (175 F. 3d at 1027).
      More generally, the panel held (over one judge's dissent) that EPA's approach to establishing
the level of the standards in 1997, both for the PM and ozone (O3) NAAQS promulgated on the same
day, effected "an unconstitutional delegation of legislative authority" (Id. at  1034-40). Although the
panel stated that "the factors EPA uses in determining the degree of public health concern associated
with different levels of ozone and PM are reasonable," it remanded the rule to EPA, stating that when
EPA considers these factors for potential non-threshold pollutants "what EPA lacks is any
determinate criterion for drawing lines" to determine where the standards should be set. Consistent
with EPA's long-standing interpretation and D.C. Circuit precedent, the panel also reaffirmed its
prior holdings that in setting NAAQS EPA is "not permitted to consider the cost of implementing
those standards" (Id. at 1040-41).
      On EPA's petition for rehearing, the panel adhered to its position on these points. American
Trucking Associations v. EPA, 195 F. 3d 4 (D.C. Cir. 1999). The full Court of Appeals denied EPA's
suggestion for rehearing en bane, with five judges dissenting (Id. at 13).
      Both sides filed cross appeals on these issues to the U.S. Supreme Court, and the Court
granted certiorari. In February 2001, the Supreme Court issued  a unanimous decision upholding
EPA's position on both  the constitutional and cost issues. Whitman v. American Trucking
Associations, 531 U.S.  457, 464,  475-76. On the constitutional issue, the  Court held that the statutory
requirement that NAAQS be "requisite" to protect public health with an adequate margin of safety
sufficiently guided EPA's discretion, affirming EPA's approach of setting standards that are neither
more nor less stringent than necessary. The Supreme Court remanded the case to the Court of
Appeals for resolution of any remaining issues that had not been addressed in that court's earlier
rulings (Id. at 475-76).  In March 2002, the Court of Appeals rejected all remaining challenges to the
standards, holding under the traditional  standard of judicial review that PM2.5 standards were
reasonably supported by the administrative record and were not "arbitrary and capricious" American
Trucking Associations v. EPA, 283 F. 3d 355, 369-72 (D.C. Cir. 2002).
      In October 1997, EPA published its plans for the third periodic review of the air quality criteria
and NAAQS for PM (62 FR 55201). After CASAC and public review, EPA finalized the 2004 PM
AQCD (U.S. EPA, 2004, 056905) and 2005 Staff Paper (U.S. EPA, 2005, 090209). For the primary
fine particle standards,  most CASAC PM Panel members favored the option of revising the level of
the 24-h PM2.5 standard in the range of 35 to 30 (ig/m3 with a 98th percentile form, in concert with
revising the level of the annual PM2.5 standard in the range of 14 to 13 (ig/m3 (Henderson, 2005,
188316). Most of the members of the CASAC PM Panel also strongly supported establishing anew,
secondary PM2 5 standard to protect urban visibility and recommended establishing a sub-daily (4- to
8-h averaging time) PM25 standard within the range of 20 to 30  ug/m3 with a form within the range
of the 92nd to 98th percentile (Henderson, 2005, 188316). For thoracic coarse particles, there was
general concurrence among CASAC PM Panel members to revise the PMi0 standards by establishing
a primary standard specifically targeted to address particles in the size range of 2.5 to 10 um
(PMio_2.5). The CASAC PM Panel was also in general agreement "that coarse particles in urban or
industrial areas are likely to be enriched by anthropogenic pollutants that tend to be inherently more
toxic than the windblown crustal  material which typically dominates coarse particle mass in arid
December 2009                                  1-6

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rural areas." Based on its review of the Staff Paper, there was general agreement among the CASAC
PM Panel members that a 24-h PMi0_2.5 standard with a level in the range of 50 to 70 (ig/m3, with a
98th percentile form, was reasonably justified and that a PMi0_2.5 standard with an annual averaging
time was not warranted (Henderson, 2005, 156537). On January 17,  2006, EPA proposed to revise
the NAAQS for PM (71 FR 2620). For fine particles, EPA proposed  to retain PM2.5 as the indicator,
to retain standards for 24-h and annual exposures, and to revise the form of the annual standard to
tighten conditions for demonstrating compliance using spatially averaged monitoring. EPA also
proposed to revise the level of the 24-h PM25 standard to 35  (ig/m3 to provide increased protection
against health effects associated with short-term PM2 5 exposures, including premature mortality and
increased hospital admission and emergency room visits, but proposed to retain the level  of the
annual PM2.5 standard at 15 (ig/m3, continuing protection against health effects associated with
long-term exposure including premature mortality and development  of chronic respiratory disease.
With regard to the primary standards for thoracic coarse particles, EPA proposed to revise the 24-h
PMio standard in part by establishing a new indicator for thoracic coarse particles (particles generally
between 2.5 and 10 (im in diameter), qualified so as to include any ambient mix of PMi0_2.5 that was
dominated by resuspended dust from high density traffic on paved roads and PM generated by
industrial sources and construction sources, and proposed to  exclude any ambient mix of PMi0_2.5
that was dominated by rural windblown dust and soils and PMi0_2.s generated by agricultural and
mining sources. EPA also proposed a detailed monitoring regime in conjunction with this proposed
indicator (71 FR 2710, 2731-42). The EPA proposed to set a  24-h standard (using the proposed
indicator) at a level of 70 (ig/m  to continue to provide a level of protection against health effects
associated with short-term exposure (including hospital admissions for cardiopulmonary  diseases,
increased respiratory symptoms and possibly premature mortality) in those areas where the proposed
indicator was found, generally equivalent to the level of protection provided by the existing 24-h
PMio standard. Also, EPA proposed to revoke, upon finalization of a primary 24-h standard for
thoracic coarse particles, the 24-h PMio standard as well as the annual PMio standard.
      EPA proposed to revise the secondary standards by making them identical to the suite of
proposed primary standards for fine and coarse particles, providing protection against PM-related
public welfare effects including visibility impairment, effects on vegetation and ecosystems, and
materials damage and soiling. EPA also solicited comment on adding a new sub-daily PM2 5
secondary standard to address visibility impairment in urban areas.
      CASAC provided additional advice to EPA in a letter to the Administrator requesting
reconsideration of CASAC's recommendations for both the primary  and secondary PM25 standards,
as well as standards for thoracic coarse particles (Henderson, 2006, 156538).
      On September 21, 2006, EPA announced its final decisions to  revise the primary and
secondary NAAQS for PM to provide increased protection of public health and welfare, respectively
(71 FR 61144). With regard to the primary and secondary standards for fine particles, EPA revised
the level of the 24-h PM25 standard to 35 (ig/m3, retained the level of the annual PM25 standard at
15 (ig/m3, and  revised the form of the annual PM25 standard  by narrowing the constraints on the
optional use of spatial averaging. EPA established the secondary standard for fine particles identical
to the primary  standards. With regard to the primary and secondary standards for thoracic coarse
particles, EPA retained PMio as the indicator for coarse particles, retained the level and form of the
24-h PM10 standard (so the standard remains 150 (ig/m3 with a one expected exceedence form) and
revoked the annual standard because available evidence generally did not support a link between
long-term exposure to current ambient levels of coarse particles and  health or welfare effects.
      Following promulgation of the revised PM NAAQS in 2006, several parties filed petitions for
review with respect to: (1) selecting the level of the annual primary PM25  standard; (2) setting the
secondary PM2 5 standards identical to the primary standards; (3) retaining PMio as the indicator for
coarse particles and retaining the level and form of the PM10 24-h standard; and (4) revoking the
PMio annual standard. On judicial review, the D.C. Circuit remanded the annual standard for fine
particles to EPA because EPA failed to adequately explain why the annual PM2 5 standard provided
the requisite protection from both short- and long-term exposures to  fine particles including
protection for vulnerable subpopulations. With respect to protection  from short-term exposures, in
1997 EPA determined that the annual standard was the generally controlling standard for lowering
both short- and long-term PM2 5 concentrations and the 24-h  standard was set to "provide an
adequate margin of safety against infrequent or isolated peak concentrations that could occur in areas
that attain the annual standard" (62 FR 38676-77, July 18,  1997). In  the 2006 decision, the
Administrator  considered it appropriate to use a somewhat different  evidence-based approach from
December 2009                                  1-7

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that used in 1997 to set the level of the 24-h and annual PM2.5 standards. In that decision, the
Administrator relied upon evidence from the short-term exposure PM2.5 studies as the principal basis
for selecting the proposed level of the 24-h standard and relied upon evidence from the long-term
exposure PM2.5 studies as the principal basis for selecting the level of the annual standard. The court
found EPA failed to adequately explain this change in approach in light of CASAC and staff's
recommendations to do otherwise. The court also found that EPA had failed to adequately explain
why a short-term 24-h standard by itself would provide the protection needed from short-term
exposures. American Farm Bureau Federation v. EPA, 559 F. 3d 512, 520-24 (D.C. Cir. 2009). With
respect to protection from long-term exposure, the court found that EPA failed to adequately explain
how the current standard provided "an adequate margin of safety for vulnerable subpopulations, such
as children, the elderly, or those with conditions that exposure them to  greater risk from fine
particles". Specifically, EPA did not provide a reasonable explanation of why certain studies,
including a study of children in Southern California showing lung damage from long-term exposure,
did not call for a more stringent annual standard (Id. at 522-23).
      The court also remanded the secondary standard for fine particles, based on EPA's failure to
adequately explain why setting the secondary NAAQS equivalent to the primary standards provided
the required protection for public welfare including protection from visibility impairment. The court
found that EPA failed to identify a target level of visibility impairment that would be requisite to
protect public welfare. This was contrary to the statute and resulted in a lack of a reasoned basis for
the final decision. In addition, EPA's near exclusive reliance on a comparison of numbers of counties
that would be in nonattainment under various types of standards was an inadequate basis for making
a decision. It  did not take into account the relative visibility protection  of different standards, as well
as the failure  of a 24-h standard to address regional differences in humidity and its effect on visibility
(Id. at 528-31).
      The court upheld EPA's decision to retain the 24-h PMi0 standard to provide protection for
coarse particle exposures and to revoke the annual PMi0 standard. The  court found that EPA
reasonably included all coarse PM within the standard, both urban and non-urban, to provide
nationwide protection for exposure to coarse PM. It rejected arguments that the evidence showed
there are no risks from exposure to non-urban coarse PM (Id. at 531-33). The court further found that
EPA had a reasonable basis to not set separate standards for urban and non-urban coarse PM, namely
the inability to reasonably define what ambient mixes would be included under either "urban" or
"non-urban." In addition, the court found that record evidence supported EPA's cautious decision to
provide "some protection from exposure to thoracic coarse particles...  in all areas." The court also
upheld EPA's decision to use PMi0 as the indicator for coarse particles  and to retain the level of the
standard at 150 (ig/m3. EPA's final rule acknowledged that evidence of harm from urban-type coarse
PM is stronger than for other types, and targeted protection at areas where urban-type coarse PM is
most likely present. The targeting is done by using the indicator PMi0 for coarse particles. PM10
includes both coarse PM and fine PM.  Urban and industrial areas tend to have higher levels of fine
PM than rural areas, so that in those areas less coarse PM is allowed - the desired targeting.
Conversely, fine PM levels tend to be lower in rural areas, so more coarse particles are  allowed in
those areas -  again the desired targeting. Likewise, the court concluded that the EPA's choice of the
level for the PMi0 standard was reasonable for many of the same reasons (Id. at 533-36). The court
also upheld EPA's decision to revoke the annual PM10 standard (Id. at 537-38).
1.3.  ISA Development
      EPA initiated the current formal review of the NAAQS for PM on June 28, 2007 with a call for
information from the public (72 FR 35462). In addition to the call for information, publications were
identified through an ongoing literature search process that includes extensive computer database
mining on specific topics. Literature searches were conducted routinely to identify studies published
since the last review, focusing on publications from 2002 to May 2009. Search strategies were
iteratively modified in an effort to optimize the identification of pertinent publications. Additional
papers were identified for inclusion in several ways: review of pre-publication tables of contents  for
journals in which relevant papers may be published; independent identification of relevant literature
by expert authors; and identification by the public and CASAC during the external review process.
Generally, only information that had undergone scientific peer review and had been published or
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accepted for publication was considered. All relevant epidemiologic, controlled human exposure,
animal toxicological, and welfare effects studies published since the last review were considered,
including those related to exposure-response relationships, mode(s) of action (MOA), or susceptible
populations.
      In general, in assessing the scientific quality and relevance of health and environmental effects
studies, the following considerations have been taken into account when selecting studies for
inclusion in the ISA or its annexes. The selection process for studies included in this ISA is shown in
Figure 1-1.

        •   Are the study populations, subjects, or animal models adequately selected and are they
           sufficiently well defined to allow for meaningful comparisons between study or exposure
           groups?

        •   Are the statistical analyses appropriate, properly performed, and properly interpreted?
           Are likely covariates adequately controlled or taken into account in the study design and
           statistical analysis?

        •   Are the PM aerometric data, exposure, or dose metrics of adequate quality and
           sufficiently representative of information regarding ambient PM?

        •   Are the health or welfare effect measurements meaningful and reliable?

      In selecting epidemiologic studies, EPA considered whether a given study contained
information on associations with short- or long-term PM exposures at or near ambient levels of PM;
evaluated health effects of PM size fractions, components or source-related indicators; considered
approaches to evaluate issues related to potential confounding by other pollutants; assessed potential
effect modifiers; and evaluated important methodological issues (e.g., lag or time period between
exposure and effects, model specifications, thresholds, mortality displacement) related to
interpretation of the health  evidence. Among the epidemiologic studies selected, particular emphasis
was placed on those studies most relevant to the review of the NAAQS. Specifically, studies
conducted in the U.S. or Canada were discussed in more detail than those from other geographical
regions. Particular emphasis was placed on: (1) recent multicity studies that employ standardized
analysis methods for evaluating effects of PM and that provide overall estimates for effects based on
combined analyses of information pooled across multiple cities; (2) studies that help understand
quantitative relationships between exposure concentrations and effects; (3) recent studies (published
since the last PM NAAQS review) that provide evidence on effects in susceptible populations; and
(4) studies that consider and report PM as  a component of a complex mixture of air pollutants.
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         Continuous,
         comprehensive
         literature review
         of peer-reviewed
         journal articles
 Studies that do
 not address
 exposure and/or
 effects of air
 pollutant(s) under
 review are
 excluded.
                                    Studies added
                                    to the docket
                                    during public
                                    comment period.
            Studies identified
            during EPA
            sponsored kickoff
            meeting (including
            studies in
            preparation).
            KEY DEFINITIONS

 INFORMATIVE studies are well-designed,
 properly implemented, thoroughly described.

 HIGHLY INFORMATIVE studies reduce
 uncertainty on critical issues, may include
 analyses of confounding or effect modification
 by copollutants or other variables, analyses of
 concentration-response or dose-response
 relationships, analyses related to time
 between exposure and response, and offer
 innovation in method or design.

 POLICY-RELEVANT studies may include
 those conducted at or near ambient concen-
 trations and studies conducted in U.S. and
 Canadian airsheds.
V	J
           nformative
            studies
         are identified
                              Studies are
                          evaluated for inclusion
                             in the ISA and/
                              or Annexes.
                         Selection of
                         studies
                         discussed and
                         additional studies
                         identified during
                         CASAC peer
                         review of draft
                         document.
Policy relevant and highly informative studies discussed in the ISA text include
those that provide a basis for or describe the association between the criteria
pollutant and effects. Studies summarized in tables and figures are included
because they are sufficiently comparable to be displayed together. A study
highlighted in the ISA text does not necessarily appear in a summary table or
figure.
                                                      ANNEXES

                        All newly identified informative studies are included in the Annexes. Older, key
                        studies included in previous assessments may be included as well.
Figure 1 -1.     Identification of studies for inclusion in the ISA.
December 2009
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      Criteria for the selection of research evaluating controlled human exposure or animal
toxicological studies included a focus on studies conducted using relevant pollutant exposures. For
both types of studies, relevant pollutant exposures are considered to be those generally within one or
two orders of magnitude of ambient PM concentrations. Studies in which higher doses were used
may also be considered if they provide information relevant to understanding MO As or mechanisms,
as noted below.
      Evaluation of controlled human exposure studies focused on those that approximated expected
human exposure conditions in terms of concentration and duration. In the selection of controlled
human exposure studies, emphasis is placed on studies that: (1) investigate potentially susceptible
populations  such as people with cardiovascular diseases or asthmatics, particularly studies that
compare responses in susceptible individuals with those in age-matched healthy controls; (2) address
issues such as concentration-response or time-course of responses; (3) investigate exposure to PM
separately and in combination with other pollutants such as O3; (4) include control exposures to
filtered air; and (5) have sufficient statistical power to assess findings.
      For selecting toxicological studies for highlighting in the text, emphasis is placed on inhalation
studies conducted at concentrations <2 mg/m3 and those studies that approximate expected human
dose conditions in terms of concentration, size distributions, and duration, which will depend on the
toxicokinetics and biological sensitivity of the particular laboratory animals examined. Studies that
elucidated MOAs and/or susceptibility, particularly if the studies were conducted under
atmospherically  relevant conditions, were emphasized whenever possible. A limited number of
toxicological studies were included that employed intratracheal (IT) instillation techniques, mainly
for PMio_2.5 studies in rodents, that explored new emerging areas of investigation (e.g., vasomotor
function), or that evaluated specific potential MOA or mechanisms of response. The sources,
transport, and fate of fibers and unique nano-materials (viz., dots, hollow spheres, rods, fibers, tubes)
are not reviewed herein because the in vivo disposition of these unique nanomaterials is not
necessarily relevant to the behavior of ultrafme (UF) aerosols in the urban environment that are
created by combustion sources and photochemical formation of secondary organic aerosols. In
considering  the potential effects of different components  of PM, EPA has focused on studies that
have assessed effects for a range of PM sources or components, including those using source
apportionment methods or comparing effects for numerous PM components, and not on studies of
individual constituents or species. Studies of ubiquitous PM sources as part of a mixture (i.e.,  diesel
exhaust, gasoline exhaust, wood smoke) are included, provided they meet the other remaining
selection criteria. Those studies of mixtures that are not a significant source of ambient PM, such as
environmental tobacco smoke (ETS), are not included.
      These criteria provide benchmarks for evaluating various studies and for focusing on the
policy relevant studies in assessing the body of health and welfare effects evidence. Detailed critical
analysis of all PM health and welfare effects studies, especially in relation to the above
considerations, is beyond the scope of this document. Of most relevance for evaluation of studies is
whether they provide useful qualitative or quantitative information on exposure-effect or
exposure-response relationships for effects associated with current ambient air concentrations of PM
that can inform decisions on whether to retain or revise the standards.
      In developing the PM ISA, EPA began by reviewing and summarizing the evidence on (1)
atmospheric sciences and exposure; (2) the health effects evidence from in vivo and in vitro animal
toxicological, controlled human exposure,  and epidemiologic studies;  and (3) the welfare effects of
PM, including visibility, climate, and ecological effects. In June 2008, EPA held a workshop to
obtain review of the scientific content of initial draft materials or sections for the draft ISA and its
annexes, that primarily contain summary information. The purpose of the initial peer review
workshop was to ensure that the ISA is up to date and focused on the most policy-relevant findings,
and to assist EPA with integration of evidence within and across disciplines. Following the peer
review workshop, EPA addressed comments from the peer review workshop and completed the
initial integration and synthesis of the evidence.
      The integration of evidence on health or welfare effects involves collaboration between
scientists from various disciplines. As described in the section below, the ISA organization is based
on health or welfare effect categories. As an example, an evaluation of health effects evidence would
include summaries of findings from epidemiologic, controlled human exposure, and toxicological
studies, and integration of the results to draw conclusions based on the causal framework described
below. Using the causal framework described in Section 1.5, EPA scientists consider aspects such as
strength, consistency, coherence and biological plausibility of the evidence, and develop draft
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causality judgments on the nature of the relationships. The draft integrative synthesis sections and
conclusions are reviewed by EPA internal experts and, as appropriate, by outside expert authors. In
practice, causality determinations often entail an iterative process of review and evaluation of the
evidence. The draft ISA is released for review by the CASAC and the public. Comments on the
characterization of the science as well as the implementation of the causal framework are carefully
considered in revising and completing the ISA.
      PMio health studies are included in this assessment because they provide important evidence
regarding the health effects  of PM in general. However, the ISA draws no conclusions regarding
causality for short- or long-term exposure to PMi0, as PMi0 is comprised of both fine and thoracic
coarse particles. As a result, causality determinations are limited to PM2.5, PMi0_2.5, and UF particle
(UFP) size fractions. In the cases where it was determined that PMip is dominated by fine or thoracic
coarse PM in specific study locations, these health studies are used in supporting the causality
determinations for PM2.5 or PM10_2.5. Epidemiologic studies of short-term exposure to PM10 are also
relied upon to examine potential effect modifiers, potential confounding by copollutants, and the
influence of different modeling approaches on PM-mortality  risk  estimates, as well as the
concentration-response relationship between PM and mortality. Therefore, to the extent possible, the
findings of PMio studies  are considered insofar as they provide  information relevant to the review of
the NAAQS for fine and thoracic coarse particles.
1.4.  Document Organization
      This ISA is composed of nine chapters. This introductory chapter presents background
information, and provides an overview of EPA's framework for making causal judgments. Key
findings and conclusions for consideration in the review of the NAAQS for PM from the
atmospheric sciences, ambient air data analyses, exposure assessment, dosimetry, health and welfare
effects, including judgments on causality for the health and welfare effects of PM exposure, are
presented in Chapter 2. More detailed summaries, evaluations and integration of the evidence are
included in Chapters 3 through 9.
      Chapter 3 highlights key concepts or issues relevant to understanding the atmospheric
chemistry, sources, and exposure of and to PM following a "source-to-exposure" paradigm.
Chapter 4 summarizes key concepts and recent findings on the dosimetry of PM, and Chapter 5
discusses possible pathways and MOA for the effects of PM.  Chapters 6 and 7  evaluate and integrate
epidemiologic, controlled human exposure, and animal toxicological information relevant to the
review of the primary NAAQS for PM. Health effects related to short-term exposures (hours to days)
to PM are the focus of Chapter 6. Chapter 7 evaluates health  evidence related to long-term exposures
(months to years) to PM. Chapters 6 and 7 are organized by health outcome categories, such as
cardiovascular or respiratory effects, and each section includes effects of the various types of PM
studied. For each health outcome category, summary sections then integrate the findings to draw
conclusions on the evidence for the main size classes of PM (i.e.,  PM25, PMi0_2.5, and UFP).
Chapter 6 also includes a summary and synthesis of the recent health evidence that uses systematic
approaches to assess health effects of sources and constituents of  ambient PM; most such studies
have evaluated effects of short-term exposure. Chapter 8 evaluates evidence related to  populations
potentially susceptible to PM-related effects.
      Chapter 9 evaluates welfare effects evidence that is relevant to the review of the  secondary
NAAQS for PM. This chapter includes consideration of effects  of PM on visibility impairment,
materials damage, effects of PM on climate, and ecological effects of PM that were not addressed in
the Integrated Science Assessment for Oxides of Nitrogen and Sulfur—Ecological Criteria (NOXSOX
ISA) (U.S. EPA, 2008,  157074). The chapter also presents key conclusions and scientific judgments
regarding causality for welfare effects of PM. In 2008, EPA completed the NOXSOX ISA (U.S. EPA,
2008, 157074). that focused on ecological effects related to the  deposition of nitrogen (N)- and sulfur
(S)-containing compounds. The 2008 NOXSOX ISA included ecological effects from particle-phase
compounds (e.g., nitrates and sulfates), primarily effects from acidification and N-nutrient
enrichment and eutrophication. In this ISA, the focus is on recent  data for direct welfare effects of
particle-phase NOX and SOX in the ambient air - primarily visibility impairment, damage to
materials, and positive and negative climate interactions - not the welfare effects related to
deposition of particle-phase NOX and SOX.
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      A series of annexes supplement this ISA. The annexes provide additional details of the
pertinent literature published since the last review, as well as selected older studies of particular
interest. These annexes contain information on:

       •  atmospheric chemistry of PM, sampling and analytic methods for measurement of PM,
          concentrations, emissions, sources and human exposure to PM (Annex A);

       •  studies on the dosimetry of PM (Annex B);

       •  controlled human exposure studies of health effects related to exposure to PM (Annex
          C);

       •  toxicological studies of health effects related to exposure to PM in laboratory animals
          and cell cultures (Annex D);

       •  epidemiologic studies of health effects from short- and long-term exposure to PM
          (Annex E); and

       •  studies that evaluate PM-induced health effects attributable to specific constituents or
          sources (Annex F).

      Within Annexes B through F, detailed information about methods and results of health studies
is summarized in tabular format, and generally includes information about: concentrations of PM
and averaging times; study methods employed; results; and quantitative results for relationships
between effects and exposure to PM. As noted in the section above, the most pertinent results of this
body of studies are brought into the ISA.



1.5.  EPA Framework for Causal Determination

      The EPA has developed a consistent and transparent basis to evaluate the causal nature of air
pollution-induced health or environmental effects. The framework described below establishes
uniform language concerning causality and brings more specificity to the findings. It drew
standardized language from across the federal government and wider scientific community,
especially from the recent National Academy of Sciences (NAS) Institute of Medicine (IOM)
document, Improving the Presumptive Disability Decision-Making Process for Veterans (IOM, 2008,
156586). the most recent comprehensive work on evaluating causality.
      This introductory section focuses on the evaluation of health effects evidence; while focusing
on human health outcomes, the concepts are also generally relevant to causality determination for
welfare effects. This section:

       •  describes the kinds of scientific evidence used in establishing a general causal
          relationship between exposure and health effects;

       •  defines cause, in contrast to statistical association;

       •  discusses the sources of evidence necessary to reach a conclusion about the existence of
          a causal relationship;

       •  highlights the issue of multifactorial causation;

       •  identifies issues and approaches related to uncertainty; and

       •  provides a framework for classifying and characterizing the weight of evidence in
          support of a general causal relationship.

      Approaches to assessing the separate and combined lines of evidence (e.g., epidemiologic,
controlled human exposure, and animal toxicological studies) have been formulated by a number of
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regulatory and science agencies, including the IOM of the NAS (IOM, 2008, 156586). International
Agency for Research on Cancer (IARC, 2006, 093206). EPA Guidelines for Carcinogen Risk
Assessment (U.S. EPA, 2005, 086237). Centers for Disease Control and Prevention (CDC, 2004,
056384). and National Acid Precipitation Assessment Program (NAPAP, 1991, 095894). These
formalized approaches offer guidance for assessing causality. The frameworks are similar in nature,
although adapted to different purposes, and have proven effective in providing a uniform structure
and language for causal determinations. Moreover, these frameworks have supported
decision-making under conditions of uncertainty.


1.5.1.   Scientific Evidence Used in Establishing Causality

      Causality determinations are based on the evaluation and synthesis of evidence  from across
scientific disciplines; the type of evidence that is most important for such determinations will vary
by assessment. The most direct evidence of a causal relationship between pollutant exposures and
human health effects  comes from controlled human exposure studies. This  type of study
experimentally evaluates the health effects of administered exposures in human volunteers under
highly-controlled laboratory conditions.
      In most epidemiologic or observational studies  of humans, the investigator does not control
exposures or intervene with the study population. Broadly, observational studies can describe
associations between exposures and effects. These studies fall into several  categories:
cross-sectional, prospective cohort, and time-series studies. "Natural experiments" offer the
opportunity to investigate changes in health with a change in exposure; these include comparisons of
health effects before and after a change in population  exposures, such as the closure of a pollution
source.
      Experimental animal data can help characterize effects of concern, exposure-response
relationships, susceptible populations, MO As and enhance understanding of biological plausibility  of
observed effects. In the absence of controlled human exposure or epidemiologic data,  animal data
alone may be sufficient to support a likely causal determination, assuming  that similar responses are
expected in humans.


1.5.2.   Association and Causation

      "Cause" is a significant, effectual relationship between an agent and an effect on health or
public welfare. "Association" is the statistical dependence among events, characteristics, or other
variables. An association is prima facie evidence for causation; alone, however, it is insufficient
proof of a causal relationship between exposure and disease or health effect. Determining whether an
observed association  is causal rather than spurious involves consideration of a number of factors, as
described below. Much of the newly available health information evaluated in this ISA comes from
epidemiologic studies that report a statistical association between ambient  exposure and health
outcomes.
      Many of the health and environmental outcomes reported in these studies have complex
etiologies. Diseases such as asthma, coronary artery disease or cancer are typically initiated by a web
of multiple agents. Outcomes depend on a variety of factors, such as age, genetic susceptibility,
nutritional status, immune competence, and social factors (Gee and Payne-Sturges, 2004, 093070;
IOM, 2008, 156586). Effects on ecosystems are also multifactorial with a complex web of causation.
Further, exposure to a combination of agents could cause synergistic or antagonistic effects. Thus,
the observed risk represents the net effect of many actions and counteractions.


1.5.3.   Evaluating Evidence for Inferring Causation

      Moving from association to causation involves  elimination of alternative explanations for the
association. In estimating the causal influence of an exposure on health or  environmental effects, it is
recognized that scientific findings include uncertainty. Uncertainty can be  defined as a state of
having limited knowledge where it is impossible to exactly describe an existing state or future
outcome; the lack of knowledge about the correct value for a specific measure or estimate.
Uncertainty characterization and uncertainty assessment are two activities  that lead to different
degrees of sophistication in describing uncertainty. Uncertainty characterization generally involves a
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qualitative discussion of the thought processes that lead to the selection and rejection of specific
data, estimates, scenarios, etc. Uncertainty assessment is more quantitative. The process begins with
simpler measures (e.g., ranges) and simpler analytical techniques and progresses, to the extent
needed to support the decision for which the assessment is conducted, to more complex measures
and techniques. Data will not be available for all aspects of an assessment, and those data that are
available may be of questionable or unknown quality. In these situations, evaluation of uncertainty
can include professional judgment or inferences based on analogy with similar situations. The net
result is that the assessments will be based on a number of assumptions with varying degrees of
uncertainty. Uncertainties  commonly encountered in evaluating health evidence for the criteria air
pollutants are outlined below for epidemiologic and experimental studies. Various approaches to
characterizing uncertainty include classical statistical methods, sensitivity analysis, or probabilistic
uncertainty analysis, in order of increasing complexity and data requirements. The ISA generally
evaluates uncertainties qualitatively in assessing the evidence from across studies; in some situations
quantitative analysis approaches, such as meta-regression may be used.
      It is important to note here that, although the following discussion refers primarily to health
effect studies, many parallels exist with welfare effects studies. Controlled exposure studies have
been conducted in which plant species have been directly exposed to air pollutants, and the strengths
and limitations  of that body of studies mirror those of the controlled human exposure studies
discussed below. Ecological field or natural gradient studies are similar to epidemiologic studies, for
example, in the study of free-living populations  and in the challenges faced in distinguishing effects
of pollutants  within a mixture.
      Controlled human exposure studies evaluate the effects of exposures to a variety of pollutants
in a highly-controlled laboratory setting. Also referred to as human clinical studies, these
experiments allow investigators to expose subjects to fixed concentrations of air pollutants under
carefully regulated environmental conditions and activity levels. Controlled human exposures to PM
typically involve exposing subjects either at rest or while  engaged in intermittent exercise in a
whole-body exposure chamber, although mouthpiece and facemask systems can also be used. A
variety of different types of particles are used in these studies including ambient outdoor particles,
concentrated  ambient particles (CAPs), diesel exhaust (DE) from a diesel engine, wood smoke
generated in a wood stove, laboratory generated model particles (e.g., elemental carbon [EC] or zinc
oxide [ZnO]), or particles  collected on a filter, resuspended in saline, and administered either
through IT instillation or inhalation. The recovery of particles on filters is variable and some
components,  such as organics, may be too volatile to be collected. Exposures to artificially generated
particles may provide important information on the health effects of PM, but are not truly
representative of ambient air pollution particles. The direct exposure of humans to ambient air
pollution particles may be complicated by factors that cannot be controlled such as coexposures to
other air pollutants (e.g., O3, SO2, and NO2). In concentrating ambient particles, gaseous  copollutants
are not proportionately concentrated and interactions between PM and the copollutants cannot be
investigated unless the latter are re-introduced. These limitations as well as daily variability in
concentration and composition can make it difficult to compare the results from controlled human
exposure studies employing particles from different sources.
      In some instances, controlled human exposure studies can also be used to characterize
concentration-response relationships at pollutant concentrations relevant to ambient conditions.
Controlled human exposures are typically conducted using a randomized crossover design with
subjects exposed both to PM and a clean air control. In this way, subjects serve as their own controls,
effectively controlling for many potential confounders. However, controlled human exposure studies
are limited by a number of factors including a small sample size and short exposure times. These
laboratory studies are often conducted at PM concentrations much higher than those typically
observed under ambient conditions, which may result in an overestimate of the acute response to
exposure in the general population. Although the repetitive nature of ambient PM exposures  may
lead to cumulative health effects, this type of exposure is not practical to replicate in a laboratory
setting. In addition, while  subjects  do serve as their own controls, personal exposure to pollutants in
the hours and days preceding the controlled exposures may vary significantly between and within
individuals. Finally, controlled human exposure studies require investigators to adhere to stringent
health criteria for a subject to be included in the study, and therefore the results cannot necessarily be
generalized to an entire population. Although some controlled human exposure studies have included
health comprised individuals  such as asthmatics or individuals with chronic obstructive pulmonary
disease (COPD) or coronary artery disease, these individuals must also be relatively healthy  and do
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not represent the most sensitive individuals in the population. Thus, a lack of observation of effects
from controlled human exposure studies does not necessarily mean that a causal relationship does
not exist. While controlled human exposure studies provide important information on the biological
plausibility of associations observed between air pollutant exposure and health outcomes in
epidemiologic studies, observed effects in these studies may underestimate the response in certain
subpopulations.
      Epidemiologic studies provide important information on the associations between health
effects and exposure of human populations  to ambient air pollution. In the evaluation of
epidemiologic evidence, one important consideration is potential confounding. Confounding is "... a
confusion of effects. Specifically, the apparent effect of the exposure of interest is distorted because
the effect of an extraneous factor is mistaken for or mixed with the actual exposure effect (which
may be null)" (Rothman  and Greenland, 1998, 086599). One approach to remove spurious
associations from possible confounders is to control for characteristics that may  differ between
exposed and unexposed persons; this is frequently termed "adjustment." Appropriate statistical
adjustment for confounders requires identifying and measuring all reasonably expected confounders.
Deciding which variables  to control for in a statistical analysis  of the association between exposure
and disease or health outcome depends on knowledge about possible mechanisms and the
distributions of these factors in the population under study. In addition, scientific judgment is needed
regarding likely sources and magnitude of confounding, together with consideration of how well the
existing constellation of study designs, results, and analyses address this potential threat to
inferential validity. One key consideration in this review is evaluation of the potential contribution of
PM to health effects when it is a component of a complex air pollutant mixture. Reported PM effect
estimates in epidemiologic studies may reflect independent PM effects on respiratory and
cardiovascular health. Ambient PM may also be serving as an indicator of complex ambient air
pollution mixtures that share the same source as PM (i.e., combustion of S-containing fuels or motor
vehicle emissions). Alternatively,  copollutants may mediate the effects of PM or PM may influence
the toxicity of copollutants.
      Another important consideration in the  evaluation of epidemiologic evidence is effect
modification. "Effect-measure modification differs from confounding in several ways. The main
difference is that, whereas confounding is a bias that the investigator hopes to prevent or remove
from the effect estimate, effect-measure modification is a property of the effect under study ... In
epidemiologic analysis one tries to eliminate confounding but one tries to detect and estimate effect-
measure modification" (Rothman and Greenland, 1998, 086599). Examples of effect modifiers in
some of the studies  evaluated in this ISA include environmental variables (e.g.,  temperature or
humidity), individual risk  factors (e.g., education, cigarette smoking status, age), and community
factors (e.g., percent of population > 65 years old).  It is often possible to stratify the relationship
between health outcome and exposure by one or more of these  risk factor variables. Effect modifiers
may be encountered (a) within single-city time-series studies; or (b) across cities in a two-stage
hierarchical model or meta-analysis.
      Several statistical methods are available to detect and control for potential confounders, with
none of them being completely  satisfactory. Multivariable regression models constitute one tool for
estimating the association between exposure and outcome after adjusting for characteristics of
participants that might confound the results. The use of multipollutant regression models has been
the prevailing approach for controlling potential confounding by  copollutants in air pollution health
effects studies. Finding the pollutant likely  responsible for the health outcome from multipollutant
regression models is made difficult by the possibility that one or more air pollutants may be acting as
a surrogate for an unmeasured or poorly-measured pollutant or for a particular mixture of pollutants.
In addition, more than one pollutant may exert similar health effects, resulting in independently
observed associations for multiple pollutants.  Further, the correlation between the air pollutant of
interest and various copollutants may make it difficult to discern  associations between different
pollutant exposures and health effects. Thus, results of models  that attempt to distinguish gaseous
and particle effects must be interpreted with caution. The number and degree of diversity of
covariates, as well as their relevance to the  potential confounders, remain matters of scientific
judgment. Despite these limitations, the use of multipollutant models is still the prevailing approach
employed in most air pollution epidemiologic studies, and provides some insight into the potential
for confounding or interaction among pollutants.
      Adjustment for potential confounders can be influenced by differential exposure measurement
error. There are several components that contribute to exposure measurement error in epidemiologic
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studies, including the difference between true and measured ambient concentrations, the difference
between average personal exposure to ambient pollutants and ambient concentrations at central
monitoring sites, and the use of average population exposure rather than individual exposure
estimates. Previous AQCDs have examined the role of measurement error in time-series
epidemiologic studies using simulated data and mathematical analyses and suggested that "transfer
of effects" would only occur under unusual circumstances (i.e., "true" predictors having high
positive or negative correlation; substantial measurement error; or extremely negatively correlated
measurement errors) (U.S. EPA, 2004, 056905).
      Confidence that unmeasured confounders are not producing the findings is increased when
multiple studies are conducted in various settings using different subjects or exposures; each of
which might eliminate another source of confounding from consideration. Thus, multicity studies
which use a consistent method to analyze data from across locations with different levels of
covariates can provide insight on potential confounding in associations. Intervention studies, because
of their quasi-experimental nature, can be particularly useful in characterizing causation.
      In addition to controlled human exposure and epidemiologic studies, the tools  of experimental
biology have been valuable for developing insights into human physiology and pathology. Animal
toxicological studies explore the effects of pollutants on human health, especially through the study
of model systems in other species. These studies evaluate the effects of exposures to  a variety of
pollutants in a highly controlled laboratory setting, and allow exploration of MO As or mechanisms
by which a pollutant may cause effects.  Background knowledge of the biological mechanisms by
which an exposure might or might not cause disease can prove crucial in establishing, or negating, a
causal claim. There are, however, uncertainties  associated with quantitative extrapolations between
laboratory animals and humans on the pathophysiological effects of any pollutant. Animal species
can differ from each other  in fundamental aspects of physiology and anatomy (e.g., metabolism,
airway branching, hormonal regulation) that may limit extrapolation. The differences between
humans and rodents with regard to pollutant absorption and distribution profiles based on breathing
pattern, exposure dose, and differences in lung structure and anatomy all have to be taken into
consideration.
      A relatively new tool available for experimental studies of PM exposure is the  particle
concentrator. Particle concentrators enable human subjects, animals, or cell culture systems to be
exposed to atmospheric PM at concentrations greater than that observed under ambient conditions.
As ambient PM is just one component of a complex mixture that interacts with gases and other
aerosols, CAPs systems provide a method of exposing subjects to the particle phase.  There are
several instrument systems used to concentrate  ambient PM in controlled human or animal exposure
studies (Gordon et al, 1999,  001176: Maciejczyk  and Chen, 2005, 087456: Sioutas et al, 1995,
001629: Sioutas et al., 1999, 001633). Gases (such as  O3 and SO2) are not concentrated nor is
PM10_2.5 (except for the coarse particle concentrator) and  only certain systems are capable of
concentrating UFPs. In UF CAPs systems, increased number fraction of organic carbon and PAHs,
along with decreased relative percentage of EC particles have been reported in concentrated PM
compared to ambient PM (Su et al., 2006, 157021). These data suggest that for UF concentrators, the
CAPs do not accurately reflect atmospheric UFP composition.
      The ability to extrapolate between species has not generally changed since the 2004 PM
AQCD but some considerations related to coarse particles merit attention. The inhalability of
particles >2.5 um in diameter is considerably lower in rats than in humans; however, once inhaled,
deposition in the extrathoracic region is near 100% percent for particles >5 um for most laboratory
animal species (rat, mouse, hamster, guinea pig, and dogs).  By contrast, penetration of thoracic
coarse particles into the lower respiratory tract is greater in humans than rodents due to the
moderately less efficient nasal deposition of humans and oronasal breathing (especially during
exercise). The extent to which coarse particle deposition in the lower respiratory tract differs
between the species is highly dependent on the  activity level of the human  exposure scenario in
contrast with the resting exposure conditions common to rodent exposures. Endotracheal  exposures
of rodents may be needed to achieve coarse particle tissue doses in the lower respiratory tract of
rodents similar to those experienced by humans. For particles <1 urn, including UFPs, deposition is
expected to be relatively similar between the species.
      There are also differences between species in both the rates of particle clearance from and
retention in the lung. The clearance rate of particles from the ciliated airways of rats is considerably
greater than humans. There is also evidence of prolonged particle retention in the  smaller
bronchioles of humans that does not appear to exist or has not been observed in rats.  Under most
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circumstances, clearance from the alveolar region of rats is also more rapid than observed in humans.
Thus, these combined effects contribute to a greater particle burden in the lower respiratory tract of
humans relative to rats. An important consideration in studies where are rats chronically exposed to
high concentrations of insoluble particles, is the potential for "overload conditions." Rats, unlike
other laboratory animals or humans, may experience a reduction in their alveolar clearance rates and
an accumulation of interstitial particle burden and under these conditions, the relevance of tissue
burdens and responses to humans is questionable. Considering interspecies differences in both
deposition and clearance, greater exposure concentrations are required to achieve coarse particle
tissue doses in the lower respiratory tract of rodents similar to those experienced by humans.


1.5.4.   Application of Framework for  Causal Determination

      EPA uses a two-step approach to evaluate the scientific evidence on health or environmental
effects of criteria pollutants. The first step determines the weight of evidence in support of causation
and characterizes the strength of any resulting causal classification. The second step includes further
evaluation of the quantitative evidence regarding the concentration-response relationships and the
loads or levels, duration and pattern of exposures at which effects are observed.
      To aid judgment, various "aspects"  of causality have been discussed by many philosophers
and scientists. The most widely cited aspects of causality in epidemiology, and public health, in
general, were  articulated by Sir Austin Bradford Hill (1965, 071664) and have been widely used
(CDC, 2004, 056384; IARC, 2006, 093206; IOM, 2008, 156586; NRC, 2004, 156814; U.S. EPA,
2005, 086237). Several adaptations of the Hill aspects have  been used in aiding causality judgments
in the ecological sciences (Adams, 2003, 156192; Collier, 2003, 155736; Fox, 1991, 156444;
Gerritsen et al, 1998, 156465).
      These aspects  (Hill, 1965, 071664) have been modified (Table 1-2) for use in causal
determinations specific to health and  welfare effects or pollutant exposures.2 Some aspects are more
likely than others to be relevant for evaluating evidence on the health or environmental effects of
criteria air pollutants. For example, the analogy aspect does  not always apply and specificity would
not be expected for multi-etiologic health  outcomes such as  asthma or cardiovascular disease, or
ecological  effects related to acidification. Aspects that usually play a larger role in determination of
causality are consistency of results across  studies, coherence of effects observed in different study
types or disciplines, biological plausibility, exposure-response relationship, and evidence from
"natural" experiments.
      Although these aspects provide a framework  for assessing the evidence, they do not lend
themselves to  being considered in terms of simple formulas  or fixed rules of evidence leading to
conclusions about causality (Hill,  1965, 071664). For example, one cannot simply count the number
of studies reporting statistically significant results or statistically nonsignificant results and reach
credible conclusions about the relative weight of the evidence and the likelihood of causality. In
addition, it is important to note that the aspects in Table 1-2  cannot be used as a strict checklist, but
rather to determine the weight of the evidence for inferring causality. While these aspects are
particularly salient in this assessment, it is also important to recognize that no one aspect is either
necessary or sufficient for drawing inferences of causality.
1 The "aspects" described by Hill (1965, 071664) have become, in the subsequent literature, more commonly described as "criteria." The
original term "aspects" is used here to avoid confusion with 'criteria' as it is used, with different meaning, in the Clean Air Act.

2 The Hill aspects were developed for interpretation of epidemiologic results. They have been modified here for use with a broader array of
data, i.e., epidemiologic, controlled human exposure, and animal toxicological studies, as well as in vitro data, and to be more consistent
with EPA's Guidelines for Carcinogen Risk Assessment.
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Table 1-2.     Aspects to aid in judging causality.
            Aspect
                                                                     Description
CONSISTENCY OF THE
OBSERVED ASSOCIATION
                                An inference of causality is strengthened when a pattern of elevated risks is observed across
                                several independent studies, conducted in multiple locations by multiple investigators. The
                                reproducibility of findings constitutes one of the strongest arguments for causality. If there are
                                discordant results among investigations, possible reasons such as differences in exposure,
                                confounding factors, and the power of the study are considered.

COHERENCE                    An inference of causality from epidemiologic associations may be strengthened by other lines of
                                evidence (e.g., controlled human exposure and animal toxicological studies) that support a
                                cause-and-effect interpretation of the association. Causality is also supported when epidemiologic
                                associations are reported across study designs and across related health outcomes. Evidence on
                                ecological or welfare effects may be drawn from a variety of experimental approaches (e.g.,
                                greenhouse, laboratory, and field) and subdisciplines of ecology (e.g., community ecology,
                                biogeochemistry and paleological/ historical reconstructions). The coherence of evidence from
                                various fields greatly adds to the strength  of an inference of causality. The absence of other lines of
                                evidence, however, is not a reason to reject causality

                                An inference of causality tends to be strengthened by consistency with data from experimental
                                studies or other sources demonstrating  plausible biological mechanisms. A proposed mechanistic
                                linking between an effect, and exposure to the agent,  is an important source of support for causality,
                                especially when data establishing the existence and functioning of those mechanistic links are
                                available. A lack of biological understanding, however, is not a reason to reject causality.
BIOLOGICAL PLAUSIBILITY
BIOLOGICAL GRADIENT
(EXPOSURE-RESPONSE
RELATIONSHIP)
                                Awell characterized exposure-response relationship (e.g., increasing effects associated with greater
                                exposure) strongly suggests cause and effect, especially when such relationships are also observed
                                for duration of exposure (e.g., increasing effects observed following longer exposure times). There
                                are, however, many possible reasons that a study may fail to detect an exposure-respor
                                relationship. Thus, although the presence of a biological gradient may support causality,
                                absence of an exposure-response relationship does not exclude a causal relationship.
                                                                                                        Ionse
                                                                                                           the
STRENGTH OF THE
OBSERVED ASSOCIATION
                                The finding of large, precise risks increases confidence that the association is not likely due to
                                chance, bias, or other factors. However, given a truly causal agent, a small magnitude in the effect
                                could follow from a lower level of exposure, a lower potency, or the prevalence of other agents
                                causing similar effects. While large effects support causality, modest effects therefore do not
                                preclude it.

                                The strongest evidence for causality can be provided when a change in exposure brings about a
                                change in occurrence or frequency of health or welfare effects.

                                Evidence of a temporal sequence between the introduction of an agent and appearance of the effect
                                constitutes another argument in favor of causality.

                                As originally intended, this refers to increased inference of causality if one cause is associated with
                                a single effect or disease (Hill, 1965,071664). Based on the current understanding this is now
                                considered one of the weaker guidelines for causality; for example, many agents cause respiratory
                                disease and respiratory disease has multiple  causes. At the scale of ecosystems, as in
                                epidemiology, complexity is such that single agents causing single effects, and single effects
                                following single causes, are extremely unlikely. The ability to demonstrate specificity  under certain
                                conditions remains, however, a powerful  attribute of experimental studies. Thus, although the
                                presence of specificity may support causality, its absence does not exclude it.

ANALOGY                      Structure activity relationships and information on the agent's structural analogs can  provide insight
                                into whether an association is causal. Similarly, information on mode of action for a chemical, as one
                                of many structural analogs, can inform decisions regarding likely causality.
EXPERIMENTAL EVIDENCE
TEMPORAL RELATIONSHIP OF
THE OBSERVED ASSOCIATION

SPECIFICITY OF THE
OBSERVED ASSOCIATION
1.5.5.   First Step—Determination of Causality

       In the ISA, EPA assesses the results of recent relevant publications, building upon evidence
available during the previous NAAQS review, to draw conclusions on the causal relationships
between relevant pollutant exposures and health or environmental effects. This ISA uses a five-level
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hierarchy that classifies the weight of evidence for causation, not just association1. In developing this
hierarchy, EPA has drawn on the work of previous evaluations, most prominently the lOM's
Improving the Presumptive Disability Decision-Making Process for Veterans (IOM, 2008, 156586],
EPA's Guidelines for Carcinogen Risk Assessment (U.S. EPA, 2005, 086237) and the U.S. Surgeon
General's smoking reports (CDC, 2004, 056384). This weight of evidence evaluation is based on
various lines of evidence from across the health and environmental effects disciplines.  These
separate judgments are integrated into a qualitative statement about the overall weight  of the
evidence and causality. The five descriptors for causal determination are described in Table 1-3.
      For PM, this determination of causality step involved a rather complex evaluation of evidence
for different PM indices, different types of health or environmental effects, and for short- and long-
term exposure periods. There were insufficient data on peak (i.e., <24 h) exposures for any PM size
fraction with health effects to make causality determinations for this exposure category. Causality
determinations were made for the PM measure (PM2.5s PM10_2.5, and UFPs, to the extent evidence was
available for each measure), the overall effect category, and the exposure duration. As noted above,
to the extent possible, results of PMi0 studies are considered in causality determinations for PM2.5
and PM 10-2.5. In the evaluation of health effects findings in Chapter 6 (for short-term exposure) and
Chapter 7 (for long-term exposure), evidence was evaluated for health outcome categories, such as
cardiovascular effects, and then conclusions were drawn based upon the integration of evidence from
across disciplines  (e.g., epidemiology, controlled human exposure, and toxicology) and also across
the suite of related individual health outcomes. Chapters 6 and 7 initially summarize and evaluate
findings for individual health outcomes, then integrate the results in summary sections to draw
conclusions on causality for each PM indicator. The causality narratives present the weight of
evidence that highlights the quality and breadth of the data, including any limitations or
uncertainties. In the integrative synthesis and conclusions in Chapter 2, the ISA presents causality
determinations and a summary of the underlying basis for those determinations for the PM indicator
(e.g., PM2.5), for the exposure time period (e.g., short- and long-term exposure) and for the major
health effect categories.
1 It should be noted that the CDC and IOM frameworks use a four-category hierarchy for the strength of the evidence. A five-level
hierarchy is used here to be consistent with the EPA Guidelines for Carcinogen Risk Assessment and to provide a more nuanced set of
categories.
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Table 1-3.     Weight of evidence for causal determination.
  Determination
Health Effects
Ecological and Welfare Effects
CAUSAL           Evidence is sufficient to conclude that there is a causal
RELATIONSHIP     relationship with relevant pollutant exposures. That is, the
                   pollutant has been shown to result in health effects in
                   studies in which chance, bias, and confounding could be
                   ruled out with reasonable confidence. For example: a)
                   controlled human exposure studies that demonstrate
                   consistent effects; or b) observational studies that cannot
                   be explained by plausible alternatives or are supported by
                   other lines of evidence (e.g., animal studies or mode of
                   action information). Evidence includes replicated and
                   consistent high-quality studies by multiple investigators.
                                Evidence is sufficient to conclude that there is a causal
                                relationship with relevant pollutant exposures. That is, the
                                pollutant has been shown to result in effects in studies in
                                which chance, bias, and confounding could be ruled out
                                with reasonable confidence. Controlled exposure studies
                                (laboratory or small- to medium-scale field studies)
                                provide the strongest evidence for causality, but the scope
                                of inference may be limited. Generally, determination is
                                based on multiple studies conducted by multiple research
                                groups, and evidence that is considered sufficient to infer
                                a causal relationship is usually obtained from the joint
                                consideration of many lines of evidence that reinforce
                                each other.
LIKELY TO BE A    Evidence is sufficient to conclude that a causal
CAUSAL           relationship is likely to exist with relevant pollutant
RELATIONSHIP     exposures, but important uncertainties remain. That is,
                   the pollutant has been shown to result in health effects in
                   studies in which chance and bias can be ruled out with
                   reasonable confidence but potential issues remain. For
                   example: a) observational studies show an association,
                   but copollutant exposures are difficult to address and/or
                   other lines of evidence (controlled human exposure,
                   animal, or mode of action information) are limited or
                   inconsistent; or b) animal toxicological evidence from
                   multiple studies from different laboratories that
                   demonstrate effects, but limited or no human data are
                   available. Evidence generally includes replicated and
                   high-quality studies by multiple investigators.
                                Evidence is sufficient to conclude that there is a likely
                                causal association with relevant pollutant exposures. That
                                is, an association has been observed between the
                                pollutant and the outcome in studies in which chance, bias
                                and confounding are minimized, but uncertainties remain.
                                For example, field studies show a relationship, but
                                suspected interacting  factors cannot be controlled, and
                                other lines of evidence are limited or inconsistent.
                                Generally, determination is based on multiple studies in
                                multiple research groups.
SUGGESTIVE OF   Evidence is suggestive of a causal relationship with
A CAUSAL         relevant pollutant exposures, but is limited because
RELATIONSHIP     chance, bias and confounding cannot be ruled out. For
                   example, at least one high-quality epidemiologic study
                   shows an association with a given health outcome but the  other studies are inconsistent.
                   results of other studies are inconsistent.
                                Evidence is suggestive of a causal relationship with
                                relevant pollutant exposures, but chance, bias and
                                confounding cannot be ruled  out. For example, at least
                                one high-quality study shows an effect, but the results of
INADEQUATE TO   Evidence is inadequate to determine that a causal
INFER A CAUSAL   relationship exists with relevant pollutant exposures. The
RELATIONSHIP     available studies are of insufficient quantity, quality,
                   consistency or statistical power to permit a conclusion
                   regarding the presence or absence of an effect.
                                The available studies are of insufficient quality,
                                consistency or statistical power to permit a conclusion
                                regarding the presence or absence of an effect.
NOT LIKELY TO     Evidence is suggestive of no causal relationship with
BE A CAUSAL      relevant pollutant exposures. Several adequate studies,
RELATIONSHIP     covering the full range of levels of exposure that human
                   beings are known to encounter and considering
                   susceptible populations, are mutually consistent in not
                   showing an effect at any level of exposure.
                                Several adequate studies, examining relationships with
                                relevant exposures, are consistent in failing to show an
                                effect at any level of exposure.
1.5.6.   Second  Step—Evaluation of Response

       Beyond judgments regarding causality are questions relevant to quantifying health or
environmental risks based on our understanding of the quantitative relationships between pollutant
exposures and health or welfare effects.


1.5.6.1.   Effects  on Human Populations

       Once a determination is made regarding the causal relationship between the pollutant and
outcome category, important questions regarding quantitative relationships include:
December 2009
                    1-21

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       •   What is the concentration-response or dose-response relationship in the human
           population?

       •   What exposure conditions (dose or exposure, duration and pattern) are important?

       •   What subpopulations appear to be differentially affected (i.e., more susceptible to
           effects)?

      To address these questions, in the second step of the EPA framework, the entirety of
quantitative evidence is evaluated to best quantify those concentration-response relationships that
exist. This requires evaluation of pollutant concentrations and exposure durations at which effects
were observed for  exposed populations including potentially susceptible populations. This
integration of evidence results in identification of a study or set of studies that best approximates the
concentration-response relationships between health outcomes and PM indicators for the U.S.
population or subpopulations, given the current state of knowledge and the uncertainties that
surrounded these estimates.
      To accomplish this, evidence from multiple and diverse types of studies is considered. To the
extent available, the ISA evaluates results from across epidemiologic studies that use various
methods to evaluate the form of relationships between PM and health outcomes, and draws
conclusions on the most well-supported shape of these relationships. Controlled human exposure
studies can also provide data on the concentration-response relationship. Animal data may inform
evaluation of concentration-response relationships,  particularly relative to MOAs,  and characteristics
of susceptible populations. For some health outcomes, the probability and severity of health effects
and associated uncertainties  can be characterized. Chapter 2 presents the integrated findings
informative for evaluation of population risks.
      An important consideration in characterizing the public health impacts associated with
exposure to a pollutant is whether the concentration-response relationship is linear across the full
concentration range encountered, or if nonlinear relationships exist along any part  of this range. Of
particular interest is the shape of the concentration-response curve at and below the level of the
current standards. The shape of the concentration-response curve varies, depending on the type of
health outcome,  underlying biological mechanisms and dose. At the human population level,
however, various sources of variability and uncertainty tend to smooth and "linearize" the
concentration-response function (such as the low data density in the lower concentration range,
possible influence  of measurement error, and individual differences in susceptibility to air pollution
health effects). In addition, many chemicals and agents may act by perturbing naturally occurring
background processes that lead  to disease, which also linearizes population concentration-response
relationships (Clewell and Crump, 2005, 156359: Crump et al., 1976, 003192: Hoel, 1980,
These attributes of population dose-response may explain why the available human data at ambient
concentrations for some environmental pollutants (e.g., PM, O3, lead [Pb], ETS, radiation) do not
exhibit evident thresholds for health effects, even though likely mechanisms include nonlinear
processes for some key events. These attributes of human population dose-response relationships
have been extensively discussed in the broader epidemiologic literature (Rothman and Greenland,
1998. 0865991
      Publication bias is a source of uncertainty regarding the magnitude of health risk estimates. It
is well understood that studies reporting non-null findings are more likely to be published than
reports of null findings,  and publication bias can  also result in overestimation of effect estimate sizes
(loannidis, 2008,  188317). For example, effect estimates from single-city epidemiologic studies have
been found to be generally larger than those from multicity studies (Anderson et al., 2005, 087916).
      Finally, identification of the susceptible population groups contributes to  an understanding of
the public health impact of pollutant exposures. Epidemiologic studies can help identify susceptible
populations by  evaluating health responses in the study population. Examples include stratified
analyses for subsets of the population under study, or testing for interactions or  effect modification
by factors such as gender, age group, or health status. Experimental studies using  animal models of
susceptibility or disease can also inform the extent to which health risks are likely greater in specific
population subgroups. Further discussion of these groups is in Chapter 8.
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1.5.6.2.   Effects on Public Welfare

      Key questions for understanding the quantitative relationships between exposure (or
concentration or deposition) to a pollutant and risk to the public welfare (e.g., ecosystems, visibility,
materials, climate):

       •   What elements of the ecosystem (e.g., types, regions, taxonomic groups, populations,
           functions, etc.) appear to be affected, or are more sensitive to effects?

       •   Under what exposure conditions (amount deposited or concentration, duration and
           pattern) are effects seen?

       •   What is the shape of the concentration-response or exposure-response relationship?

      Evaluations of causality typically consider the probability of welfare effects changing in
response to exposure. A challenge to the quantification of exposure-response relationships for
ecological effects is the variability across ecosystems. Ecological responses are evaluated within the
range of observations, so a quantitative relationship may be determined for a given ecological system
and scale. However, there is great regional and local variability in  ecosystems. Thus, exposure-
response relationships are often  available site by site, rather than at the national or even regional
scale. For example, an ecological response to deposition of a given pollutant can differ greatly
between ecosystems. Where results from greenhouse or animal ecotoxicological studies are
available, they may be used to aid in characterizing exposure-response relationships, particularly
relative to mechanisms of action, and characteristics of sensitive biota.


1.5.7.   Concepts in Evaluating Adversity of Health Effects

      In evaluating the health evidence, a number of factors can be considered in determining the
extent to which health effects are "adverse" for health outcomes such as changes in lung function.
What constitutes an adverse health effect may vary between populations. Some changes in healthy
individuals may not be considered adverse while those of a similar type and magnitude are
potentially adverse in more susceptible individuals.
      The American Thoracic Society (ATS) published an official  statement titled What Constitutes
an Adverse Health Effect of Air Pollution? (ATS, 2000, 011738). This statement updated the
guidance for defining adverse respiratory health effects that had been published 15 years earlier
(ATS, 1985, 006522). taking into account new investigative approaches used to identify the effects
of air pollution and reflecting concern for impacts of air pollution on specific susceptible groups. In
the 2000 update, there was an increased focus on quality of life measures as indicators of adversity
and a more specific consideration of population risk. Exposure to air pollution that increases the risk
of an adverse effect to the entire population is viewed as adverse, even though it may not increase
the risk of any identifiable individual to an unacceptable level; estimated mean population effects do
not reflect more severe effects in individuals. For example, a population of asthmatics could have a
distribution of lung function such that no identifiable individual has a level associated with
significant impairment. Exposure to air pollution could shift the distribution such that no identifiable
individual experiences clinically-relevant effects; this  shift toward decreased lung function, however,
would be considered adverse because individuals within the population would have  diminished
reserve function and, therefore, would be at increased risk to further environmental insult.
1.6.  Summary
      This ISA is a review, synthesis, and evaluation of the most policy-relevant science, and
communicates critical science judgments relevant to the NAAQS review. It reviews the most
policy-relevant evidence from environmental effects studies and includes information on
atmospheric chemistry, PM sources and emissions, exposure, and dosimetry. This ISA incorporates
clarification and revisions based on advice and comments provided by EPA's CASAC (Samet, 2009,
190992; Samet, 2009, 199522). Annexes to the IS A provide additional details of the literature
published since the last review. A framework for making critical judgments concerning causality
December 2009                                  1-23

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appears in this chapter. It relies on a widely accepted set of principles and standardized language to
express evaluation of the evidence. This approach can bring rigor and clarity to current and future
assessments. This ISA should assist EPA and others, now and in the future, to accurately represent
what is presently known—and what remains unknown—concerning the effects of PM on human
health and public welfare.
December 2009                                  1-24

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                                  Chapter  1  References
Adams SM. (2003). Establishing causality between environmental stressors and effects on aquatic ecosystems. Hum Ecol
       Risk Assess, 9: 17-35. 156192

Anderson HR; Atkinson RW; Peacock JL; Sweeting MJ; Marston L. (2005). Ambient particulate matter and health effects:
       Publication bias in studies of short-term associations. Epidemiology, 16: 155-163. 087916

ATS. (1985). American Thoracic Society: Guidelines as to what constitutes an adverse respiratory health effect, with
       special reference to epidemiologic studies of air pollution. Am Rev Respir Dis, 131:  666-668. 006522

ATS. (2000). What constitutes an adverse health effect of air pollution? Official statement of the American Thoracic
       Society. Am J Respir Grit Care Med, 161: 665-673. 011738

CDC. (2004). The health consequences of smoking: A report of the Surgeon General. Centers for Disease Control and
       Prevention, U.S. Department of Health and Human Services. Washington, DC. 056384

Clewell HJ; Crump KS. (2005). Quantitative estimates of risk for noncancer endpoints. Risk Anal, 25: 285-289. 156359

Collier TK. (2003). Forensic ecotoxicology: Establishing causality between contaminants and biological effects in field
       studies. Hum Ecol Risk Assess, 9: 259 - 266. 155736

Crump KS; Hoel DG; Langley CH; Peto R. (1976). Fundamental carcinogenic processes and their implications for low
       dose risk assessment. Cancer Res, 36: 2973-2979. 003192

Fox GA. (1991). Practical causal inference for ecoepidemiologists. J Toxicol Environ Health, 33: 359-373. 156444

Gee GC; Payne-Sturges DC. (2004). Environmental health disparities: A framework integrating psychosocial and
       environmental concepts. Environ Health Perspect, 112: 1645-1653. 093070

Gerritsen J; Carlson RE; Dycus DL; Faulkner C; Gibson GR. (1998). Lake and reservoir bioassessment and biocriteria:
       Technical guidance document. US Environmental Protection Agency, Office of Water. Washington, DC. EPA 841-
       B-98-007. http://www.epa.gov/owow/monitoring/tech/lakes.html. 156465

Gordon T; Gerber H; Fang CP; Chen LC. (1999). A centrifugal particle  concentrator for use  in inhalation toxicology. Inhal
       Toxicol, 11: 71-87. 001176

Henderson R. (2005). Clean Air Scientific Advisory Committee (CASAC) review of the EPA staff recommendations
       concerning a Potential Thoracic Coarse PM standard in the Review of the National Ambient Air Quality Standards
       for Particulate Matter: Policy Assessment of Scientific and Technical Information. U.S. Environmental Protection
       Agency. Washington, DC. 156537

Henderson R. (2005). EPA's Review of the National Ambient Air Quality Standards for Particulate Matter (Second Draft
       PM Staff Paper, January 2005): A review by the Particulate Matter Review Panel of the EPA Clean Air Scientific
       Advisory Committee. U.S. Environmental Protection Agency. Washington D.C.. 188316

Henderson R. (2006). Clean Air Scientific Advisory Committee recommendations concerning the proposed National
       Ambient Air Quality Standards for particulate matter. U.S. Environmental Protection Agency. Washington, DC.
       156538

Hill AB. (1965). The environment and disease: Association or causation. J R Soc Med, 58: 295-300. 071664

Hoel DG. (1980). Incorporation of background in dose-response models. Fed Proc, 39: 73-75. 156555

IARC. (2006). IARC monographs on the evaluation of carcinogenic risks to humans: Preamble. International Agency for
       Research on Cancer. Lyon,France  . http://monographs.iarc.fr/ENG/Preamble/CurrentPreamble.pdf. 093206

loannidis JPA. (2008). Why most discovered true associations are inflated. Epidemiology, 19: 640-648. 188317
Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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IOM. (2008). Improving the Presumptive Disability Decision-Making Process for Veterans; Committee on Evaluation of
       the Presumptive Disability Decision-Making Process for Veterans, Board on Military and Veterans Health.
       Washington, DC: Institue of Medicine of the National Academies, National Academies Press. 156586

Maciejczyk P; Chen LC. (2005). Effects of subchronic exposures to concentrated ambient particles (CAPs) in mice: VIII
       source-related daily variations in in vitro responses to CAPs. Inhal Toxicol, 17: 243-253. 087456

NAPAP. (1991). The experience and legacy of NAPAP report of the Oversight Review Board. National Acid Precipitation
       Assessment Program. Washington, DC. 095894

NAPCA. (1969). Air quality criteria for particulate matter. National Air Pollution Control Administration. Washington, DC.
       014684

NRC. (2004). Research priorities for airborne particulate matter: IV Continuing research progress. National Academies
       Press. Washington, DC. 156814

RothmanKJ; Greenland S. (1998). Modern epidemiology. Philadelphia, PA: Lippincott-Raven Publishers. 086599

Samet JM. (2009). CASAC Review of integrated science assessment for particulate matter (second external review draft,
       July 2009). U.S. Environmental Protection Agency. Washington, D.C.. EPA-CASAC-10-001.199522

Samet JM. (2009). Review of EPA's Integrated Science Assessment for Particulate Matter (First External Review Draft,
       December 2008). Clean Air Scientific Advisory Committee (CASAC) and members of the CASAC Particulate
       Matter (PM) Review Panel, Science Advisory Board, U.S. Environmental Protection Agency. Washington, D.C..
       EPA-CASAC-09-008. 190992

Sioutas C; Kim S; Chang M. (1999). Development and evaluation of a prototype ultrafine particle concentrator. J Aerosol
       Sci, 30: 1001-1017.001633

Sioutas D; Koutrakis P; Ferguson ST; Burton RM. (1995). Development and evaluation of a prototype ambient particle
       concentrator for inhalation exposure studies. Inhal Toxicol, 7: 633-644. 001629

Su Y; Sipin MF; Spencer MT; Qin X; Moffet RC; Shields LG; Prather KA; Venkatachari P; Jeong C-H; Kim E; Hopke PK;
       Gelein RM; Utell MJ; Oberdorster G; Berntsen J; Devlin RB; Chen LC. (2006). Real-time characterization of the
       composition of individual particles emitted from ultrafine particle concentrators. Aerosol Sci Technol, 40: 437-455.
       157021

U.S. EPA. (2004). Air quality criteria for particulate matter. U.S. Environmental Protection Agency. Research Triangle
       Park, NC. EPA/600/P-99/002aF-bF. 056905

U. S. EPA. (2005). Guidelines for carcinogen risk assessment, Risk Assessment Forum Report. U. S. Environmental
       Protection Agency. Washington, DC. EPA/630/P-03/001F. http://cfpub.epa.gov/ncea/index.cfm. 086237

U.S. EPA. (2005). Review of the national ambient air quality standards for particulate matter: Policy assessment of
       scientific and technical information OAQPS staff paper. U.S. Environmental Protection Agency. Washington, DC.
       EPA/452/R-05-005a. http://www.epa.gov/ttn/naaqs/standards/pm/data/pmstaffpaper_20051221 .pdf. 090209

U.S. EPA. (2008). Integrated review plan for the national ambient air quality standards for particulate matter. U.S.
       Environmental Protection Agency, Office of Research and Development, National Center for Environmental
       Assessment. Research Triangle Park, NC. 157072

U.S. EPA. (2008). Integrated science assessment for oxides of nitrogen and sulfur: Ecological criteria. U.S. Environmental
       Protection Agency. Research Triangle Park, NC. EPA/600/R-08/082F. 157074
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          Chapter  2.  Integrative  Health  and
                  Welfare  Effects Overview
      The subsequent chapters of this ISA will present the most policy-relevant information related
to this review of the NAAQS for PM. This chapter integrates the key findings from the disciplines
evaluated in this current assessment of the PM scientific literature, which includes the atmospheric
sciences, ambient air data analyses, exposure assessment, dosimetry, health studies
(e.g., toxicological, controlled human exposure, and epidemiologic), and welfare effects. The EPA
framework for causal determinations described in Chapter 1 has been applied to the body of
scientific evidence in order to collectively examine the health or welfare effects attributed to PM
exposure in a two-step process.
      As described in Chapter 1, EPA assesses the results of recent relevant publications, building
upon evidence available during the previous NAAQS reviews, to draw conclusions on the causal
relationships between relevant pollutant exposures and health or environmental effects. This ISA
uses a five-level hierarchy that classifies the weight of evidence for causation:

       •  Causal relationship

       •  Likely to be a causal relationship

       •  Suggestive of a causal relationship

       •  Inadequate to infer a causal relationship

       •  Not likely to be a causal relationship

      Beyond judgments regarding causality are questions relevant to quantifying health or
environmental risks based on our understanding of the quantitative relationships between pollutant
exposures and health or welfare effects. Once a determination is made regarding the causal
relationship between the pollutant and outcome category, important questions regarding quantitative
relationships include:

       •  What is the concentration-response or dose-response relationship?

       •  Under what exposure conditions (amount deposited, dose or concentration, duration and
          pattern) are effects observed?

       •  What populations appear to be differentially  affected (i.e., more susceptible) to effects?

       •  What elements of the ecosystem (e.g., types, regions, taxonomic groups, populations,
          functions, etc.) appear to be affected, or are more sensitive to effects?

      To address these questions, in the second step of the EPA framework, the entirety of
quantitative evidence is evaluated to identify and characterize potential concentration-response
relationships. This requires evaluation of levels of pollutant and exposure durations at which effects
were observed for exposed populations including potentially susceptible populations.
      This chapter summarizes and integrates the newly available  scientific evidence that best
informs consideration of the policy-relevant questions that frame this assessment, presented in
Chapter 1. Section 2.1  discusses the trends in ambient concentrations and sources of PM and
provides a brief summary of ambient air quality.  Section 2.2 presents the evidence regarding
personal exposure to ambient PM in outdoor and indoor  microenvironments, and it discusses the
 Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
 Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
 developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
December 2009                                  2-1

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relationship between ambient PM concentrations and exposure to PM from ambient sources.
Section 2.3 integrates the evidence for studies that examine the health effects associated with short-
and long-term exposure to PM and discusses important uncertainties identified in the interpretation
of the scientific evidence. Section 2.4 provides a discussion of policy-relevant considerations, such
as potentially susceptible populations, lag structure, and the PM concentration-response relationship,
and PM sources and constituents linked to health effects. Section 2.5 summarizes the evidence for
welfare effects related to PM exposure. Finally, Section 2.6 provides all of the causal determinations
reached for each of the health outcomes and PM exposure durations evaluated in this ISA.



2.1.  Concentrations and Sources of Atmospheric PM
2.1.1.  Ambient PM Variability and Correlations

      Recently, advances in understanding the spatiotemporal distribution of PM mass and its
constituents have been made, particularly with regard to PM2.5 and its components as well as
ultrafme particles (UFPs). Emphasis in this ISA is placed on the period from 2005-2007,
incorporating the most recent validated EPA Air Quality System (AQS) data. The AQS is EPA's
repository for ambient monitoring data reported by the national, and state and local air monitoring
networks.  Measurements of PM2.5 and PMi0 are reported into AQS, while PMi0_2.5 concentrations are
obtained as the difference between PMi0 and PM2 5 (after converting PMi0 concentrations from STP
to local  conditions; Section 3.5). Note, however, that a majority of U.S. counties were not
represented in AQS because their population fell below the regulatory monitoring threshold.
Moreover, monitors reporting to AQS were not uniformly distributed across the U.S. or within
counties, and conclusions drawn from AQS data may  not apply equally to all parts of a geographic
region. Furthermore, biases  can exist for some PM constituents (and hence total mass) owing to
volatilization losses of nitrates and other semi-volatile compounds, and, conversely, to retention of
particle-bound water by hygroscopic species. The degree of spatial variability in PM was likely to be
region-specific and strongly influenced by local sources and meteorological and topographic
conditions.


2.1.1.1.   Spatial Variability across the U.S.

      AQS data for daily average concentrations  of PM25 for 2005-2007 showed considerable
variability across the U.S. (Section 3.5.1.1). Counties  with the highest average concentrations of
PM2.5 (>18 (ig/m3) were reported for several counties  in the San Joaquin Valley and inland southern
California as well as Jefferson County, AL (containing Birmingham) and Allegheny County, PA
(containing Pittsburgh). Relatively few regulatory monitoring sites have the appropriate co-located
monitors for computing PMi0_2.5, resulting in poor geographic coverage on a national scale
(Figure  3-10). Although the  general understanding of  PM differential settling leads to an expectation
of greater  spatial heterogeneity in the PMi0_2.s fraction, deposition of particles as a function of size
depends strongly on local meteorological conditions. Better geographic coverage is available for
PMio, where the highest reported annual average  concentrations (>50 (ig/m3) occurred in southern
California, southern Arizona and central New Mexico. The size distribution of PM varied
substantially by location, with a generally larger fraction of PMi0 mass in the PMi0_2.s size range in
western cities (e.g., Phoenix and Denver) and a larger fraction of PMi0 in the PM25 size range in
eastern U.S. cities (e.g., Pittsburgh and Philadelphia).  UFPs are not measured as part of AQS or any
other routine regulatory network in the U.S. Therefore, limited information is available regarding
regional variability in the spatiotemporal distribution  of UFPs.
      Spatial variability in PM2 5 components obtained from the Chemical Speciation Network
(CSN) varied considerably by species from 2005-2007 (Figures 3-12 through 3-18). The highest
annual average organic carbon (OC) concentrations were observed in the western and southeastern
U.S. OC concentrations in the western U.S. peaked in the fall and winter, while OC concentrations in
the  Southeast peaked anytime between spring and fall. Elemental carbon (EC) exhibited less
seasonality than OC and showed lowest seasonal  variability in the eastern half of the U.S. The
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highest annual average EC concentrations were present in Los Angeles, Pittsburgh, New York, and
El Paso. Concentrations of sulfate (SO42~) were higher in the eastern U.S. as a result of higher SO2
emissions in the East compared with the West.  There is also considerable seasonal variability with
higher SO42~ concentrations in the summer months when the oxidation of SO2 proceeds at a faster
rate than during the winter. Nitrate (NO3~) concentrations were highest in California and during the
winter in the Upper Midwest. In general, NO3~ was higher in the winter across the country, in part as
a result of temperature-driven partitioning and  volatilization. Exceptions existed in Los Angeles and
Riverside, CA, where high NO3~ concentrations appeared year-round. There is variation in both
PM2.5 mass and composition among cities, some of which might be due to regional differences in
meteorology, sources, and topography.


2.1.1.2.   Spatial Variability on the Urban  and Neighborhood Scales

      In general, PM2 5 has a longer atmospheric lifetime than PMi0_2.5. As a result, PM2 5 is more
homogeneously distributed than PMi0_2.5, whose concentrations more closely reflect proximity to
local sources (Section 3.5.1.2). Because PMi0 encompasses PMi0_2.5 in addition to PM25, it also
exhibits more spatial heterogeneity than PM2 5. Urban- and neighborhood-scale variability in PM
mass and composition was examined by focusing on 15 metropolitan areas, which were chosen
based on their geographic distribution and coverage in recent health effects studies. The urban areas
selected were Atlanta, Birmingham, Boston, Chicago, Denver, Detroit, Houston, Los Angeles, New
York, Philadelphia, Phoenix, Pittsburgh, Riverside, Seattle and St. Louis. Inter-monitor correlation
remained higher over long distances for PM25 as compared with PMi0 in these 15 urban areas. To  a
large extent, greater variation in PM2 5 and PMi0 concentrations within cities was observed in areas
with lower ratios of PM25 to PM10. When the data was limited to only sampler pairs with less than
4 km separation (i.e., on a neighborhood scale), inter-sampler correlations remained higher for PM2 5
than for PMi0. The average inter-sampler correlation was 0.93 for PM25, while it dropped to 0.70 for
PMio (Section 3.5.1.3). Insufficient data were available in the 15 metropolitan areas to perform
similar analyses for PMi0_2.5 using co-located, low volume FRM monitors.
      As previously mentioned, UFPs are not measured as part of AQS or any other routine
regulatory network in the U.S. Therefore, information about the spatial variability of UFPs is sparse;
however, their number concentrations are expected to be highly spatially and temporally variable.
This has been shown on the urban scale in studies in which UFP number concentrations drop off
quickly with distance from roads compared to accumulation mode particle numbers.


2.1.2.  Trends and Temporal Variability

      Overall, PM25 concentrations decreased  from 1999 (the beginning of nationwide monitoring
for PM2.5) to 2007 in all ten EPA Regions, with the 3-yr avg of the 98th percentile of 24-h PM2.5
concentrations dropping 10% over this time period. However from 2002-2007, concentrations of
PM25 were nearly constant with decreases observed in only some EPA Regions (Section 3.5.2.1).
Concentrations of PM25 components were only available for 2002-2007 using CSN data and showed
little decline over this time period.  This trend in PM2 5 components is consistent with trends in PM2 5
mass concentration observed after 2002 (shown in Figures 3-44 through 3-47). Concentrations of
PMi0 also declined from 1988 to 2007 in all ten EPA Regions.
      Using hourly PM observations in the  15  metropolitan areas, diel variation showed average
hourly peaks that differ by size fraction and region (Section 3.5.2.3). For both PM25 and PMi0, a
morning peak was typically observed starting at approximately  6:00 a.m., corresponding with the
start of morning rush hour. There was also an evening concentration peak that was broader than the
morning peak and extended into the overnight period, reflecting the concentration increase caused by
the usual collapse of the mixing layer after sundown. The magnitude and duration of these peaks
varied considerably by metropolitan area investigated.
      UFPs were found to exhibit similar two-peaked diel patterns in Los Angeles and the San
Joaquin Valley of CA and Rochester, NY as well as in Kawasaki City, Japan, and Copenhagen,
Denmark. The morning peak in UFPs likely represents primary source emissions, such as rush-hour
traffic, while the afternoon peak likely represents the combination of primary source emissions and
nucleation of new particles.
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2.1.3.  Correlations between Copollutants

      Correlations between PM and gaseous copollutants, including SO2, NO2, carbon monoxide
(CO) and O3, varied both seasonally and spatially between and within metropolitan areas
(Section 3.5.3). On average, PM2.5 and PMi0 were correlated with each other better than with the
gaseous copollutants. Although data are limited for PMi0_2.5, the available data suggest a stronger
correlation between PM10 and PM 10.2.5 than between PM2 5 and PM10_2.5 on a national basis.There was
relatively little seasonal variability in the mean correlation between PM in both size fractions and
SO2 and NO2. CO, however, showed higher correlations with PM2 5 and PMi0 on average in the
winter compared with the other seasons. This seasonality results in part because a larger fraction of
PM is primary in origin during the winter. To the extent that this primary component of PM is
associated with common combustion  sources of NO2 and CO, then higher correlations with these
gaseous copollutants are to be expected. Increased atmospheric stability in colder months also results
in higher correlations between primary pollutants (Section 3.5).
      The correlation between daily maximum 8-h avg O3 and 24-h avg PM2 5 showed the highest
degree of seasonal variability with positive correlations on average in summer (avg = 0.56) and
negative correlations on average in the winter (avg = -0.30). During the transition seasons, spring
and fall, correlations were mixed but on average were still positive. PM2 5 is both primary and
secondary in origin, whereas O3 is only secondary. Photochemical production of O3 and secondary
PM in the planetary boundary layer (PBL) is much slower during  the winter than during other
seasons. Primary pollutant concentrations (e.g.,  primary PM2 5 components, NO and NO2) in many
urban areas are elevated in winter as the result of heating emissions, cold starts and low mixing
heights. O3 in the PBL during winter is mainly associated with air subsiding from above the
boundary layer following the passage of cold fronts, and this subsiding air has much lower PM
concentrations than are present in the PBL. Therefore, a negative  association between O3 andPM25
is frequently observed in the winter. During summer, both O3 and secondary PM2 5 are produced in
the PBL and in the lower free troposphere at faster rates compared to winter, and so they tend to be
positively correlated.


2.1.4.  Measurement Techniques

      The federal reference methods (FRMs) for PM2 5 and PM10  are based on criteria outlined in the
Code of Federal Regulations. They are, however, subject to several limitations that should be kept in
mind when using compliance monitoring data for health studies. For example, FRM techniques are
subject to the loss of semi-volatile species such  as organic compounds and ammonium nitrate
(especially in the West). Since  FRMs  based on gravimetry use 24-h integrated filter samples to
collect PM mass, no information is available for variations over shorter averaging times from these
instruments. However, methods have  been developed to measure real-time PM mass concentrations.
Real-time (or continuous and semi-continuous)  measurement techniques are also available for PM
species, such as particle into liquid sampler (PILS) for multiple ions analysis and aerosol mass
spectrometer (AMS) for multiple components analysis (Section 3.4.1). Advances have also been
achieved in PM organic speciation. New 24-h FRMs and Federal Equivalent Methods (FEMs) based
on gravimetry and continuous FEMs for PMi0_2.5 are available. FRMs for PMi0_2.5 rely on calculating
the difference between co-located PM10 and PM2 5 measurements while a dichotomous sampler is
designated as an FEM.


2.1.5.  PM Formation in the Atmosphere  and Removal

      PM in the atmosphere contains  both primary (i.e., emitted directly by sources) and secondary
components, which can be anthropogenic or natural in origin. Secondary PM components can be
produced by the oxidation of precursor gases  such as SO2 and NOX to acids followed by
neutralization with ammonia (NH3) and the partial oxidation of organic compounds. In addition to
being emitted as primary particles, UFPs are produced by the nucleation of H2SO4 vapor, H2O vapor,
and perhaps NH3 and certain organic compounds. Over most of the earth's surface, nucleation is
probably the major mechanism forming new UFPs. New UFP formation has been observed in
environments ranging from relatively unpolluted marine and continental environments to polluted
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urban areas as an ongoing background process and during nucleation events. However, as noted
above, a large percentage of UFPs come from combustion-related sources such as motor vehicles.
      Developments in the chemistry of formation of secondary organic aerosol (SOA) indicate that
oligomers are likely a major component of OC in aerosol samples. Recent observations also suggest
that small but significant quantities of SOA are formed from the oxidation of isoprene in addition to
the oxidation of terpenes and organic hydrocarbons with six or more carbon atoms. Gasoline engines
have been found to emit a mix of nucleation-mode heavy and large poly cyclic aromatic
hydrocarbons on which unspent fuel and trace  metals can condense, while diesel particles are
composed of a soot nucleus on which sulfates and hydrocarbons can condense. To the extent that the
primary component of organic aerosol is overestimated in emissions from combustion sources, the
semi-volatile components are underestimated. This situation results from the lack of capture of
evaporated semi-volatile components upon dilution in common emissions tests. As a result, near-
traffic sources of precursors to SOA would be underestimated. The oxidation of these precursors
results in more oxidized forms of SOA than previously considered, in both near source urban
environments and further downwind. Primary organic aerosol can also be further oxidized to forms
that have many characteristics in common with oxidized SOA formed from gaseous precursors.
Organic peroxides constitute a significant fraction of SOA and represent an important class of
reactive oxygen species (ROS) that have high oxidizing potential. More information on sources,
emissions and deposition of PM are included in Section 3.3.
      Wet and dry deposition are important processes for removing PM and other pollutants from the
atmosphere on urban, regional, and global scales. Wet deposition includes incorporation of particles
into cloud droplets that fall as rain (rainout) and collisions with falling rain (washout). Other
hydrometeors (snow, ice) can also serve the same purpose. Dry deposition involves transfer of
particles through gravitational settling and/or by  impaction on surfaces by turbulent motions. The
effects of deposition of PM on ecosystems and materials are discussed in Section 2.5  and in
Chapter 9.


2.1.6.  Source Contributions to PM

      Results of receptor modeling calculations indicate that PM2.5 is produced mainly by
combustion of fossil fuel, either by stationary sources or by transportation. A relatively small number
of broadly defined source categories, compared to the total number of chemical species that typically
are measured in ambient monitoring source receptor studies, account for the majority of the observed
PM mass. Some ambiguity is  inherent in identifying source categories. For example, quite different
mobile sources  such as trucks, farm equipment, and locomotives rely on diesel engines and ancillary
data is often required to resolve these sources. A compilation of study results shows that secondary
SO42~ (derived mainly from SO2 emitted by Electricity Generating Units [EGUs]), NO3~ (from the
oxidation of NOX emitted mainly from transportation sources and EGUs), and primary mobile source
categories, constitute most of PM2.5 (and PMi0) in the East. PMi0_2.5 is mainly primary in origin,
having been emitted as fully formed particles derived from abrasion  and crushing processes, soil
disturbances, plant and insect fragments, pollens and other microorganisms, desiccation of marine
aerosol emitted from bursting bubbles, and hygroscopic fine PM expanding with humidity to coarse
mode. Gases such as HNO3 can also condense directly onto preexisting coarse particles. Suspended
primary coarse PM can contain Fe, Si, Al, and base cations from soil, plant and insect fragments,
pollen, fungal spores, bacteria, and viruses, as well as fly ash,  brake lining particles, debris, and
automobile tire fragments.  Quoted uncertainties in the source apportionment of constituents in
ambient aerosol samples typically range from 10 to 50%. An intercomparison of source
apportionment techniques indicated that the same major source categories of PM25 were consistently
identified by several independent groups working with the same data sets. Soil-, sulfate-, residual
oil-, and salt-associated mass  were most clearly identified by the groups.  Other sources with more
ambiguous signatures, such as vegetative burning and traffic-related emissions were less consistently
identified.
      Spatial variability in source contributions across urban areas is an important consideration in
assessing the likelihood of exposure error in epidemiologic studies relating health outcomes to
sources. Concepts similar to those for using ambient concentrations as surrogates for personal
exposures apply here. Some source attribution studies for PM2 5  indicate that intra-urban variability
increases in the following order: regional sources (e.g., secondary SO42~ originating from EGUs)
< area sources (e.g., on-road mobile sources) < point sources (e.g., metals from stacks of smelters).
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Although limited information was available for PM10_2.5, it does indicate a similar ordering, but
without a regional component (resulting from the short lifetime of PMi0_2.5 compared to transport
times on the regional scale). More discussion on source contributions to PM is available in
Section 3.6.
2.1.7.  Policy-Relevant Background
      The background concentrations of PM that are useful for risk and policy assessments, which
inform decisions about the NAAQS are referred to as policy-relevant background (PRB)
concentrations. PRB concentrations have historically been defined by EPA as those concentrations
that would occur in the U.S. in the absence of anthropogenic emissions in continental North America
defined here as the U.S., Canada,  and Mexico. For this document, PRB concentrations include
contributions from natural sources everywhere in the world and from anthropogenic sources outside
continental North America. Background concentrations so defined facilitated separation of pollution
that can be controlled by U.S. regulations or through international agreements with neighboring
countries from those that were judged to be generally uncontrollable by the U.S. Over time,
consideration of potential broader ranging international agreements may lead to alternative
determinations of which PM source contributions should be considered by EPA as part of PRB.
      Contributions to PRB concentrations of PM include both primary and secondary natural and
anthropogenic components. For this document, PRB concentrations of PM2.5 for the continental U.S.
were estimated using EPA's Community Multi-scale Air Quality (CMAQ) modeling system, a
deterministic, chemical-transport model (CTM), using output from GEOS-Chem a global-scale
model for CMAQ boundary conditions. PRB concentrations of PM2.5 were estimated to be less than
1 (ig/m3 on an annual basis, with maximum daily average values in a range from 3.1 to 20 (ig/m3 and
having a peak of 63 (ig/m3 at the nine national park sites across the U.S. used to evaluate model
performance for this analysis. A description of the models  and evaluation of their performance is
given in Section 3.6 and further details about the calculations of PRB concentrations are given in
Section 3.7.
2.2.  Human Exposure
      This section summarizes the findings from the recent exposure assessment literature. This
summary is intended to support the interpretation of the findings from epidemiologic studies and
reflects the material presented in Section 3.8. Attention is given to how concentration metrics can be
used in exposure assessment and what errors and uncertainties are incurred for different approaches.
Understanding of exposure errors is important because exposure error can potentially bias an
estimate of a health effect or increase the size of confidence intervals around a health effect estimate.
2.2.1.  Spatial Scales of PM Exposure Assessment

      Assessing population-level exposure at the urban scale is particularly relevant for time-series
epidemiologic studies, which provide information on the relationship between health effects and
community-average exposure, rather than an individual's exposure. PM concentrations measured at a
central-site ambient monitor are used as surrogates for personal PM exposure. However, the
correlation between the PM concentration measured at central-site ambient monitor(s) and the
unknown true community average concentration depends on the spatial distribution of PM, the
location of the monitoring site(s) chosen to represent the community average, and division of the
community by terrain features or local sources into several sub-communities that differ in the
temporal pattern of pollution. Concentrations of SO42~ and some components of SOA measured at
central-site monitors are expected to be uniform in urban areas because of the regional nature of their
sources. However, this is not true for primary components like EC whose sources are strongly
spatially variable in urban areas.
      At micro-to-neighborhood scales, heterogeneity of sources and topography contribute to
variability in exposure. This is particularly true for PMi0_2.5 and for UFPs, which have spatially
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variable urban sources and loss processes (mainly gravitational settling for PM10_2.5 and coagulation
for UFPs) that also limit their transport from sources more readily than for PM2 5. Personal activity
patterns also vary across urban areas and across regions. Some studies, conducted mainly in Europe,
have found personal PM2.5 and PMi0 exposures for pedestrians in street canyons to be higher than
ambient concentrations measured by urban central site ambient monitors. Likewise,
microenvironmental UFP  concentrations were observed to be substantially higher in near-road
environments, street canyons, and tunnels when compared with urban background concentrations.
In-vehicle UFP and PM2.5 exposures can also be important. As a result, concentrations measured by
ambient monitors likely do not reflect the contributions of UFP or PM25 exposures to individuals
while commuting.
      There is significant  variability within and across regions of the country with respect to indoor
exposures to ambient PM. Infiltrated ambient PM concentrations depend in part on the ventilation
properties of the building  or vehicle in which the person is exposed. PM infiltration factors  depend
on particle size, chemical  composition, season, and region of the country. Infiltration can best be
modeled dynamically rather than being represented by a single value.  Season is important to PM
infiltration because it affects the ventilation practices (e.g., open windows) used. In addition, ambient
temperature and humidity conditions affect the transport, dispersion, and size distribution of PM.
Residential air exchange rates have been observed to be higher in the summer for regions with low
air conditioning usage. Regional differences in air exchange rates (Southwest < Southeast
< Northeast < Northwest) also reflect ventilation practices. Differential infiltration occurs as a
function of PM size and composition (the latter of which is described below). PM infiltration is
larger for accumulation mode particles than for UFPs and PMi0_2 5.  Differential infiltration by size
fraction can affect exposure estimates if not accurately characterized.


2.2.2.  Exposure to  PM Components and Copollutants

      Emission inventories and source apportionment studies suggest that sources of PM exposure
vary by region. Comparison of studies performed in the eastern U.S. with studies performed in the
western U.S. suggest that  the contribution of SO42~ to exposure is higher for the East (16-46%)
compared with the West (-4%) and that motor vehicle emissions and secondary NO3~ are larger
sources of exposure for the West (-9%)  as compared with the East  (-4%). Results of source
apportionment studies of exposure to SO42~ indicate that SO42~ exposures are mainly attributable to
ambient sources.  Source apportionment  for OC and EC is difficult because they  originate from both
indoor and outdoor sources. Exposure to OC of indoor and outdoor origin can be distinguished by
the presence of aliphatic C-H groups generated indoors, since outdoor concentrations of aliphatic
C-H are low. Studies of personal exposure to ambient trace metal have shown significant variation
among cities and over seasons. This is in response to geographic and seasonal variability in sources
including incinerator operation, fossil fuel combustion, biomass combustion (wildfires), and the
resuspension of crustal materials in the built environment. Differential infiltration is also affected by
variations in particle composition and volatility. For example, EC infiltrates more readily than OC.
This can lead to outdoor-indoor differentials in PM  composition.
      Some studies have explored the relationship between PM and copollutant gases and suggested
that certain gases can serve as surrogates for describing exposure to other air pollutants. The findings
indicate that ambient concentrations  of gaseous copollutants can  act as surrogates for personal
exposure to ambient PM.  Several studies have concluded that ambient concentrations of O3, NO2,
and SO2 are associated with the ambient component of personal exposure to total PM25. If
associations between ambient gases and personal exposure to PM2 5 of ambient origin exist, such
associations are complex and vary by season and location.


2.2.3.  Implications for Epidemiologic Studies

      In epidemiologic studies, exposure may be estimated using various approaches, most of which
rely on measurements obtained using central site monitors. The magnitude and direction of the
biases introduced through error in exposure measurement depend on the extent to which the error is
associated with the measured PM concentration. In  general, when exposure error is not strongly
correlated with the measured PM concentration, bias is toward the null and effect estimates are
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underestimated. Moreover, lack of information regarding exposure measurement error can also add
uncertainty to the health effects estimate.
      One important factor to be considered is the spatial variation in PM concentrations. The degree
of urban-scale spatial variability in PM concentrations varies across the country and by size fraction.
PM2.5 concentrations are relatively well-correlated across monitors in the urban areas examined for
this assessment. The limited available evidence indicates that there is greater spatial variability in
PMio_2.5 concentrations than PM2.5 concentrations, resulting in increased exposure error for the larger
size fraction. Likewise, studies have shown UFPs to be more spatially variable across urban areas
compared to PM2.5. Even if PM2.5, PMi0_2.5, or UFP concentrations measured at sites within an urban
area are generally highly correlated, significant spatial variation in their concentrations can occur on
any given day. In addition, there can be differential exposure errors for PM components (e.g., SO42~,
OC, EC). Current information suggests that UFPs, PMi0_2.5s and some PM components are more
spatially variable than PM25. Spatial variability of these PM indicators adds uncertainty to exposure
estimates.
      Overall, recent studies generally confirm and build upon the key conclusions of the 2004 PM
AQCD: separation of total PM exposures into ambient and nonambient components reduces
potential uncertainties in the analysis and interpretation of PM health effects data; and ambient PM
concentration can be used as a surrogate for ambient PM exposure in community time-series
epidemiologic studies because the change in ambient PM concentration should be reflected in the
change in the health risk coefficient. The use  of the community average ambient PM25 concentration
as a surrogate for the community average personal exposure to ambient PM2 5 is not expected to
change the principal conclusions from time-series and most panel epidemiologic studies that use
community average health and pollution data. Several recent studies support this by showing  how
the ambient component of personal exposure to PM25 could be estimated using various tracer and
source apportionment techniques and by showing that the ambient component is highly correlated
with ambient concentrations of PM25. These studies show that the non-ambient component of
personal exposure to PM2 5 is largely uncorrelated with ambient PM2 5 concentrations. A few panel
epidemiologic studies have included personal as well as ambient monitoring data, and generally
reported associations with all types of PM measurements. Epidemiologic studies of long-term
exposure typically exploit the differences in PM concentration across space, as well as time, to
estimate the effect of PM on the health outcome of interest. Long-term exposure estimates are most
accurate for pollutants that do not vary substantially within the geographic area studied.



2.3.   Health  Effects

      This section evaluates the evidence from toxicological, controlled human exposure,  and
epidemiologic studies that examined the health effects associated with short- and long-term exposure
to PM (i.e., PM25, PMio_2.5 and UFPs). The results from the health studies  evaluated in combination
with the evidence from atmospheric chemistry and exposure assessment studies contribute to  the
causal determinations made for the health outcomes discussed in this assessment (a description of
the causal framework can be found in Section 1.5.4). In the following sections a discussion of the
causal determinations will be presented by PM size fraction and exposure duration (i.e., short- or
long-term exposure) for the health effects for which sufficient evidence was available to conclude a
causal, likely to be causal or suggestive relationship. Although not presented in depth in this chapter,
a detailed discussion of the underlying evidence used to formulate each causal determination  can be
found in Chapters 6 and 7.
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2.3.1.  Exposure to PM2.s
2.3.1.1.   Effects of Short-Term Exposure to PM2.5
Table 2-1.    Summary of causal determinations for short-term exposure to PM2.6.
      Size Fraction
             Outcome
          Causality Determination
                      Cardiovascular Effects
                                 Causal
         PM2
Respiratory Effects
Likely to be causal
                      Mortality
                                 Causal
      Cardiovascular Effects

      Epidemiologic studies that examined the effect of PM2.5 on cardiovascular emergency
department (ED) visits and hospital admissions reported consistent positive associations
(predominantly for ischemic heart disease [IHD] and congestive heart failure [CHF]), with the
majority of studies reporting increases ranging from 0.5 to 3.4% per 10 ug/m3 increase in PM25.
These effects were observed in study locations with mean1 24-h avg PM2.5 concentrations ranging
from 7-18 ug/m3 (Section 6.2.10). The largest U.S.-based multicity study evaluated, Medicare Air
Pollution Study (MCAPS), provided evidence of regional heterogeneity (e.g., the largest excess risks
occurred in the Northeast [1.08%]) and seasonal variation (e.g., the largest excess risks occurred
during the winter season [1.49%]) in PM2.5 cardiovascular disease (CVD) risk estimates, which is
consistent with the null findings of several single-city studies conducted in the western U.S. These
associations are supported by multicity epidemiologic studies that observed consistent positive
associations between short-term exposure to PM2 5 and cardiovascular mortality and also reported
regional and seasonal variability in risk estimates. The multicity studies evaluated reported
consistent increases in cardiovascular mortality ranging from 0.47 to 0.85% in study locations with
mean 24-h avg PM25 concentrations above 12.8 ug/m3 (Table 6-14).
      Controlled human exposure studies have demonstrated PM2 5-induced changes in various
measures of cardiovascular function among healthy and health-compromised adults. The most
consistent evidence is for altered vasomotor function following exposure to diesel exhaust (DE) or
CAPs with O3 (Section 6.2.4.2). Although these findings provide biological plausibility for the
observations from epidemiologic studies, the fresh DE used in the controlled human exposure
studies evaluated contains gaseous components (e.g., CO, NOX), and therefore, the possibility that
some of the changes in vasomotor function might be due to gaseous components cannot be ruled out.
Furthermore, the prevalence of UFPs in fresh DE limits the ability to conclusively attribute the
observed effects to either the UF  fraction or PM25 as  a whole. An evaluation of toxicological studies
found evidence for altered vessel tone and microvascular reactivity, which provide coherence and
biological plausibility for the vasomotor effects that have been observed in both the controlled
human exposure and epidemiologic studies (Section 6.2.4.3). However, most of these toxicological
studies exposed animals via intratracheal (IT) instillation or using relatively high inhalation
concentrations.
      In addition to the effects observed on vasomotor function, myocardial ischemia has been
observed across disciplines through PM2 5 effects on ST-segment depression, with toxicological
studies providing biological plausibility by demonstrating reduced blood flow during ischemia
(Section 6.2.3). There is also a growing body of evidence from controlled human exposure and
toxicological studies demonstrating PM2 5-induced changes on heart rate variability (HRV) and
1 In this context mean represents the arithmetic mean of 24-h avg PM concentrations.
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markers of systemic oxidative stress (Sections 6.2.1 and 6.2.9, respectively). Additional but
inconsistent effects of PM2.5 on blood pressure (BP), blood coagulation markers, and markers of
systemic inflammation have also been reported across disciplines. Toxicological studies have
provided biologically plausible mechanisms (e.g., increased right ventricular pressure and
diminished cardiac contractility) for the associations observed between PM2 5 and CHF in
epidemiologic studies.
      Together, the collective evidence from epidemiologic, controlled human exposure, and
toxicoiogicai studies is sufficient to conclude that a causal relationship exists between short-
term exposures to PM  and  cardiovascular effects.


      Respiratory  Effects

      The recent epidemiologic studies evaluated report consistent positive associations between
short-term exposure to PM2.5 and respiratory ED visits and hospital admissions for chronic
obstructive pulmonary disease (COPD) and respiratory infections (Section 6.3). Positive associations
were also observed for asthma ED visits  and hospital admissions for adults and children combined,
but effect estimates are imprecise and not consistently positive for children alone. Most studies
reported effects in the  range of ~1% to 4% increase in respiratory hospital admissions and ED visits
and were observed in study locations with mean 24-h avg PM2.5 concentrations ranging from
6.1-22 (ig/m3. Additionally, multicity epidemiologic studies reported consistent positive associations
between short-term exposure to  PM2 5 and respiratory mortality as well as regional and seasonal
variability in risk  estimates. The multicity studies evaluated reported consistent, precise increases in
respiratory mortality ranging from 1.67 to 2.20% in study locations with mean 24-h avg PM25
concentrations above 12.8 ug/m3 (Table 6-14). Evidence for PM25-related respiratory effects was
also observed in panel studies, which indicate associations with respiratory symptoms, pulmonary
function, and pulmonary inflammation among asthmatic children. Although not consistently
observed, some controlled human exposure studies have reported small decrements in various
measures of pulmonary function following controlled exposures to PM25 (Section 6.3.2.2).
      Controlled human exposure studies using adult volunteers have demonstrated increased
markers of pulmonary inflammation following exposure to a variety of different particle types;
oxidative responses  to DE and wood smoke; and exacerbations of allergic responses and allergic
sensitization following exposure to DE particles (Section 6.3). Toxicological studies have provided
additional support for  PM2 5-related respiratory effects through inhalation exposures of animals to
CAPs, DE, other traffic-related PM and wood smoke. These studies reported an array of respiratory
effects including altered pulmonary function, mild pulmonary inflammation and injury, oxidative
responses, airway hyperresponsiveness (AHR) in allergic and non-allergic animals, exacerbations of
allergic responses, and increased susceptibility to infections (Section 6.3).
      Overall, the evidence for an effect  of PM25 on respiratory outcomes is somewhat restricted by
limited coherence between some of the findings  from epidemiologic and controlled human exposure
studies for the specific health outcomes reported and the sub-populations in which those health
outcomes occur. Epidemiologic  studies have reported variable results among specific respiratory
outcomes, specifically in asthmatics (e.g., increased respiratory symptoms in asthmatic children, but
not increased asthma hospital admissions and ED visits) (Section 6.3.8). Additionally, respiratory
effects have not been consistently demonstrated following controlled exposures to PM2 5 among
asthmatics or individuals with COPD.  Collectively,  the epidemiologic, controlled human exposure,
and toxicoiogicai  studies evaluated demonstrate a wide range of respiratory responses, and although
results are not fully consistent and coherent across studies the evidence is sufficient to conclude that
a causal relationship  is likely to exist between short-term exposures to PM   and
respiratory effects.


      Mortality

      An evaluation of the epidemiologic literature indicates consistent positive associations
between short-term exposure to  PM2 5 and all-cause, cardiovascular-, and respiratory-related
mortality (Section 6.5.2.2.). The evaluation of multicity studies found that consistent and precise risk
estimates for all-cause (nonaccidental) mortality that ranged from 0.29 to 1.21% per 10 (ig/m3
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increase in PM2.5 at lags of 1 and 0-1 days. In these study locations, mean 24-h avg PM2.5
concentrations were 12.8 (ig/m3 and above (Table 6-14). Cardiovascular-related mortality risk
estimates were found to be similar to those for all-cause mortality; whereas, the risk estimates for
respiratory-related mortality were consistently larger (i.e., 1.01-2.2%) using the same lag periods and
averaging indices. The studies evaluated that examined the relationship between short-term exposure
to PM2.5 and cardiovascular effects (Section  6.2) provide coherence and biological plausibility for
PM2.5-induced cardiovascular mortality, which represents the largest component of total
(nonaccidental) mortality (~ 35%) (American Heart Association, 2009, 198920). However, as noted
in Section 6.3, there is limited coherence between some of the respiratory morbidity findings from
epidemiologic and controlled human exposure studies for the specific health outcomes reported and
the subpopultions in which those health outcomes occur, complicating the interpretation of the PM25
respiratory mortality effects observed. Regional and seasonal patterns in PM2 5 risk estimates were
observed with the greatest effect estimates occurring in the eastern U.S. and during the spring. Of the
studies evaluated only Burnett et al. (2004, 086247),  a Canadian multicity study, analyzed gaseous
pollutants and found mixed results, with possible confounding of PM2 5 risk estimates by NO2.
Although the recently evaluated U.S.-based multicity studies did not analyze potential confounding
of PM25 risk estimates by gaseous pollutants, evidence from the limited number of single-city
studies evaluated in the 2004 PM AQCD (U.S. EPA,  2004, 056905) suggest that gaseous
copollutants do not confound the PM2 5-mortality association. This is further supported by studies
that examined the PMio-mortality relationship. An examination of effect modifiers (e.g.,
demographic and socioeconomic factors), specifically air conditioning use as an indicator for
decreased pollutant penetration indoors, has  suggested that PM2 5 risk estimates increase as the
percent of the population with access to air conditioning decreases. Collectively, the epidemiologic
literature provides evidence that a causal relationship exists between short-term exposures
to PM2.5 and mortality.


2.3.1.2.   Effects of Long-Term Exposure to PM2.5
Table 2-2.    Summary of causal determinations for long-term exposure to PM2.6.
Size Fraction
PM2.5
Outcome
Cardiovascular Effects
Respiratory Effects
Mortality
Reproductive and Developmental
Cancer, Mutagenicity, and Genotoxicity
Causality Determination
Causal
Likely to be causal
Causal
Suggestive
Suggestive
      Cardiovascular Effects

      The strongest evidence for cardiovascular health effects related to long-term exposure to PM2 5
comes from large, multicity U.S.-based studies, which provide consistent evidence of an association
between long-term exposure to PM25 and cardiovascular mortality (Section 7.2.10). These
associations are supported by a large U.S.-based epidemiologic study (i.e., Women's Health Initiative
[WHI] study) that reports associations between PM2 5 and CVDs among post-menopausal women
using a  1-yr avg PM25 concentration (mean = 13.5 (ig/m3) (Section 7.2). However, epidemiologic
studies that examined subclinical markers of CVD report inconsistent findings. Epidemiologic
studies have also provided some evidence for potential modification of the PM25-CVD association
when examining individual-level data, specifically smoking status and the use of anti-
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hyperlipidemics. Although epidemiologic studies have not consistently detected effects on markers
of atherosclerosis due to long-term exposure to PM2.5, toxicological studies have provided strong
evidence for accelerated development of atherosclerosis in ApoE~'~ mice exposed to CAPs and have
shown effects on coagulation, experimentally-induced hypertension, and vascular reactivity (Section
7.2.1.2). Evidence from toxicological studies provides biological plausibility and coherence with
studies of short-term exposure and cardiovascular morbidity and mortality, as well as with studies
that examined long-term exposure to PM2.5 and cardiovascular mortality. Taken together, the
evidence from epidemiologic and toxicological studies is sufficient to conclude that 3 C3US3I
relationship exists between long-term exposures to PM   and  cardiovascular effects.


      Respiratory Effects

      Recent epidemiologic studies conducted in the U.S. and abroad provide evidence of
associations between long-term exposure to PM2.5 and decrements in lung function growth, increased
respiratory  symptoms, and asthma development in study locations with mean PM2.5 concentrations
ranging from 13.8 to 30 ug/m3 during the study periods (Section 7.3.1.1 and Section 7.3.2.1).  These
results are supported by studies that observed associations between long-term exposure to PMi0 and
an increase in respiratory symptoms and reductions in lung function growth in  areas where PMi0 is
dominated by PM2 5. However, the evidence to support an association with long-term exposure to
PM2 5 and respiratory mortality is limited (Figure 7-8). Subchronic and chronic toxicological studies
of CAPs, DE, roadway air and woodsmoke provide coherence and biological plausibility for the
effects observed in the epidemiologic studies. These toxicological studies have presented some
evidence for altered pulmonary function, mild inflammation, oxidative responses, immune
suppression, and histopathological changes including mucus cell hyperplasia (Section 7.3).
Exacerbated allergic responses have been demonstrated in animals exposed to DE  and wood smoke.
In addition, pre- and postnatal exposure to ambient levels of urban particles was found to affect lung
development in an animal model. This finding is important because impaired lung development is
one mechanism by which PM exposure may  decrease lung function growth in children. Collectively,
the evidence from epidemiologic and toxicological studies is sufficient to conclude that 3 C3US3I
relationship is likely to exist  between  long-term exposures to  PM25 and respiratory
effects.


      Mortality

      The recent epidemiologic literature reports associations between long-term PM2 5 exposure and
increased risk of mortality. Mean PM25 concentrations ranged from 13.2 to 29 (ig/m3 during the
study period in these areas  (Section 7.6). When evaluating cause-specific mortality, the strongest
evidence can be found when examining associations between PM2 5 and cardiovascular mortality,
and positive associations were also reported between PM2 5 and lung cancer mortality (Figure 7-8).
The cardiovascular mortality association has been confirmed further by the extended Harvard Six
Cities and American Cancer Society studies, which both report strong associations between long-
term exposure to PM2 5 and cardiopulmonary and IHD mortality (Figure 7-7). Additional new
evidence from a study that used the WHI cohort found a particularly strong association between
long-term exposure to PM2 5 and CVD mortality in post-menopausal women. Fewer studies have
evaluated the respiratory component of cardiopulmonary mortality, and, as a result, the evidence to
support an association with long-term exposure to PM2 5 and respiratory mortality is limited (Figure
7-8). The evidence for cardiovascular and respiratory morbidity due to short- and long-term exposure
to PM2 5 provides biological plausibility for cardiovascular- and respiratory-related mortality.
Collectively, the evidence is sufficient to conclude that 3 C3US3I relstionship exists between
long-term  exposures to PM25 and mortality.
December 2009                                 2-12

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      Reproductive and Developmental Effects

      Evidence is accumulating for PM2.5 effects on low birth weight and infant mortality, especially
due to respiratory causes during the post-neonatal period. The mean PM2.5 concentrations during the
study periods ranged from 5.3-27.4 ug/m3 (Section 7.4), with effects becoming more precise and
consistently positive in locations with mean PM2.5 concentrations of 15 ug/m3 and above
(Section 7.4). Exposure to PM2.5 was usually associated with greater reductions in birth weight than
exposure to PMi0. The evidence from a few U.S. studies that investigated PMi0 effects on fetal
growth, which reported similar decrements in birth weight, provide consistency for the PM2 5
associations observed and strengthen the interpretation that particle exposure may be causally related
to reductions in birth weight. The epidemiologic literature does not consistently report associations
between long-term exposure to PM and preterm birth, growth restriction, birth defects or decreased
sperm quality. Toxicological evidence supports an association between PM2 5 and PMi0 exposure and
adverse reproductive and developmental outcomes, but provide little mechanistic information or
biological plausibility for an association between long-term PM exposure and adverse birth
outcomes (e.g., low birth weight or infant mortality). New evidence from animal toxicological
studies on heritable mutations is of great interest, and warrants further investigation. Overall, the
epidemiologic and toxicological evidence is suggestive of a causal relationship between long-
term exposures to PM25 and reproductive and developmental outcomes.


      Cancer, Mutagenicity, and Genotoxicity

      Multiple epidemiologic studies have shown a consistent positive association between PM2 5
and lung  cancer mortality, but studies have generally not reported associations between PM2 5 and
lung cancer incidence (Section 7.5). Animal toxicological studies have examined the potential
relationship between PM and cancer, but have not focused on specific size fractions of PM. Instead
they have examined ambient PM, wood smoke, and DEP A number of studies indicate that ambient
urban PM, emissions from wood/biomass burning, emissions from coal combustion, and gasoline
and DE are mutagenic, and that PAHs are genotoxic. These findings are consistent with earlier
studies that concluded that ambient PM and PM from specific combustion sources are mutagenic and
genotoxic and provide biological plausibility for the results observed in the epidemiologic studies. A
limited number of epidemiologic and toxicological studies examined epigenetic effects, and
demonstrate that PM induces some changes in methylation. However, it has yet to be determined
how these alterations in the genome could influence the initiation and promotion  of cancer.
Additionally, inflammation and immune suppression induced by  exposure to PM  may confer
susceptibility to cancer. Collectively, the evidence from epidemiologic studies, primarily those of
lung cancer mortality, along with the toxicological studies that show some evidence of the mutagenic
and genotoxic effects of PM is suggestive of a causal relationship between long-term
exposures to PM25 and cancer.


2.3.2.  Integration of PM2.5 Health  Effects

      In epidemiologic studies, short-term exposure to PM2 5 is associated with a broad range of
respiratory and cardiovascular effects, as well as mortality.  For cardiovascular effects  and mortality,
the evidence supports the existence of a causal relationship with short-term PM2 5 exposure; while the
evidence indicates that a causal relationship is likely to exist between short-term PM2  5 exposure and
respiratory effects. The effect  estimates from recent and older U.S. and Canadian-based
epidemiologic studies that examined the relationship between short-term exposure to PM2 5 and
health outcomes with mean 24-h avg PM25 concentrations <17 ug/m3  are shown in Figure 2-1. A
number of different health effects are included in Figure 2-1 to provide an integration  of the range of
effects by mean concentration, with a focus on cardiovascular and respiratory effects and all-cause
(nonaccidental) mortality (i.e., health effects categories with at least a suggestive  causal
determination). A pattern of consistent positive associations with mortality and morbidity effects can
be seen in this figure. Mean PM25  concentrations ranged from 6.1 to 16.8 ug/m3.in these study
locations.
December 2009                                 2-13

-------
Study
Outcome
Mean3   98tha
Effect Estimate (95% Cl)
Chimonas & Gessner (2007.093261)
Lisabeth et al. (2008, 155939)
Slaughter et al. (2005, 073854)
Rabinovitch et al. (2006, 088031)
Chen etal. (2004.087262)
Chen etal. (2005,087555)
Fung etal. (2006, 089789)
Villeneuve et al. (2003, 055051)
Stieb etal. (2000.011675)
Villeneuve et al. (2006, 090191)
Lin etal. (2005. 087828)
Mar etal. (2004. 057309)
Rich etal. (2005. 079620)
Dockery etal. (2005, 078995)
Rabinovitch et al. (2004, 096753)
Pope etal. (2006.091246)
Slaughter etal. (2005. 073854)
Pope etal. (2008. 191969)
Zanobetti and Schwartz (2006, 090195)
Peters etal. (2001.016546)
Delfino etal. (1997. 082687)
Sullivan etal. (2005,050854)
Burnett etal. (2004.086247)
Bell etal. (2008. 156266)
Wilson etal. (2007,1 571 49f
Zanobetti & Schwartz (2009, 188462)
Burnett and Goldberg (2003, 042798)
Dominici et al. (2006, 088398)
Fairley (2003, 042850)
Zhang etal. (2009. 191970)
O'Connor et al. (2008, 156818)
Klemm and Mason (2003, 042801)
Franklin etal. (2008, 097426)
NYDOH (2006, 090132)
Ito etal. (2007. 156594)
Franklin etal. (2007,091257)
Rich etal. (2006.089814)
Symons etal. (2006,091258)
Sheppard (2003, 042826)
NYDOH (2006, 090132)
Burnett etal. (1997.084194)
b Study did not present mean; median presented.
Asthma HA 6.1
LRI HA 6.1
IschemicStroke/TIAHA 7.0°
Asthma Exacerbation 7.3°
Asthma Medication Use 7.4
COPD HA 7.7
Respiratory HA 7.7
Respiratory HA 7.7
Nonaccidental Mortality 7.9
CVD ED Visits 8.5
Respiratory ED Visits 8.5
Hemhrgc Stroke HA 8.5
Ischemic Stroke HA 8.5
TIAHA 8.5
RTI HA 9.6
Respiratory Symptoms (any) 9.8C
Respiratory Symptoms (any) 9.8°
Ventricular Arrhythmia 9.8°
Ventricular Arrhythmia 10.3°
Asthma Exacerbation 10.6°
IHDHA 10.7C
CVD HA 10.8
Respiratory ED Visits 10.8
CHFHA 10.8
Ml HA 11.1e
Pneumonia HA 11.1°
Ml 12.1
Respiratory HA (summer) 12.1
Ml 12.8
Nonaccidental Mortality 12.8
Respiratory HA 12.9"
CVD HA 12.9"
CVD Mortality 13.0.
Nonaccidental Mortality 13.2"
Nonaccidental Mortality 13.3
CBVDHA 13.3
PVDHA 13.3
IHDHA 13.3
Dysrhythmia HA 13.3
CHFHA 13.3
COPD HA 13.3
RTIHA 13.3
Nonaccidental Mortality 13.6
ST Segment Depression 13.9
Wheeze/Cough 14.0C.
Nonaccidental Mortality 14.7°''
Nonaccidental mortality 14.8
Asthma ED Visits 15.0"
Asthma HA 15.1
Non-accidental Mortality 15.6
Ventricular Arrhythmia 16.2°
CHFHA 16.5"
Asthma HA 16.7
Asthma ED Visits 167
Respiratory HA (summer) 1 6.8
CVD HA (summer) 16.8
' Averaged annual values for years in study
provided by study author.

23.6r -" — • 	
17.2r -*•-

07 Or L^^A 	
273'- (-^





t
on or" * *
29.6r — »~
29.6'. -»*•
*-•-
OP. of -.
38.0f »
34.2r *
34.2' »
rj-t p* t || 	 |__
-31 .O. I 1 1
34.3' »
38.9' »
34.8' *
34.8' *
34.8r fc
34.8' k
34.8' i*
34.8' k
34.8' *
59.0' L+-
37.6f -»-. —
39.09 	 *i 	
h
43.0' b
39.0f -•-
45.8' i.
50 1f » i
46.6r -+-
/I7/I' ) (
171' i t
rom data
1 ! 1 1 I 1 1 1 I 1
                      .
    Mean value slightly different from those reported in the published
study or not reported in the published study; mean was either provided
by study authors or calculated from data provided by study authors.
  s Mean value not reported in study; median presented.
    98th percentile of PM2 5 distribution was either provided by study
authors or calculated from data provided by study authors.
  3 98th estimated from data in study.
 Air quality data obtained from original study by  rt c
Schwartz et al. (1996, 077325)            u-°
J Mean PM2 5 concentration reported is for lag 0-2.
k Bronx; TEOM data.
' Manhattan; TEOM data.
m Study does not present an overall effect estimate; the
vertical lines represent the effect estimate for each of the
areas of Phoenix examined.
                      0.8       1.0        1.2
                          Relative Risk / Odds Ratio
                                                                                                            1.4
Figure 2-1.     Summary of effect estimates (per 10 ug/m3) by increasing concentration from U.S.
                  studies examining the association between short-term exposure to PM2.6 and
                  cardiovascular and respiratory effects, and mortality, conducted in locations
                  where the reported mean  24-h  avg PM2.6 concentrations were <17 ug/m3.
December 2009
                  2-14

-------
      Long-term exposure to PM2.5 has been associated with health outcomes similar to those found
in the short-term exposure studies, specifically for respiratory and cardiovascular effects and
mortality. As found for short-term PM2.5 exposure, the evidence indicates that a causal relationship
exists between long-term PM2.5 exposure and cardiovascular effects and mortality, and that a causal
relationship is likely to exist between long-term PM2.5 exposure and effects on the respiratory
system.
      Figure 2-2 highlights the findings of epidemiologic studies where the long-term mean PM2 5
concentrations were < 29 ug/m3. A range of health outcomes are displayed (including cardiovascular
mortality, all-cause mortality, infant mortaltiy, and bronchitis) ordered by mean concentration. The
range of mean PM25 concentrations in these studies was 10.7-29 ug/m3 during the study periods.
Additional  studies not included in this figure that focus on subclinical outcomes, such as changes in
lung function or atherosclerotic markers also report effects in areas with similar concentrations
(Sections 7.2 and 7.3). Although not highlighted in the summary figure, long-term PM2 5 exposure
studies also provide evidence for reproductive and developmental effects (i.e., low birth weight) and
cancer (i.e., lung cancer mortality) in  response to to exposure to PM2 5.
Study
Zeqeretal. (2008. 191951)
Zegeretal. (2008, 191951)
Eftimetal. (2008, 099104)
MrPnnnoll otal fOC\m ClAQAQCh
Zegeretal. (2008, 191951)
Krewski et al. (2009, 191193)
Eftimetal. (2008.099104)
Lipfertetal. (2006, 088756)
FVirkprv pt al f1QQfi n4R91Cfi
Woodruff et al. (2008, 098386)
Laden etal. (2006, 087605)
Wnnrlriiff ptal C9HHR HQR^RQ
Enstrom (2005. 087356)
Chen et al (2005 087942)


* Mean estimated from data in stu
Outcome
All-Cause Mortality, Central U.S.
All-Cause Mortality, Western U.S.
All-Cause Mortality, ACS Sites

All-Cause Mortality, Eastern U.S.
All-Cause Mortality
All-Cause Mortality, Harv 6-Cities
All-Cause Mortality
Infant Mortality (Respiratory)
All-Cause Mortality
All-Cause Mortality
PHD Mnrtalitv MalpQ

dy
Mearv
10.7
13.1 ~J
13.6
•10 Q
14.0
14.0
14.1
14.3
1/1 c
14.8 J
14.8*
10°
23.4
290
""10

1 1
0.7 0.9
Effect Estimate (95% Cl)
— •—
L
-

—~-
L_ 	
~


1 1 1 1 1 1
1.1 1.3 1.5 1.7 1.9 2.1
                                                                 Relative Risk
Figure 2-2.
Summary of effect estimates (per 10 ug/m3) by increasing concentration from U.S.
studies examining the association between long-term exposure to PM2.s and
cardiovascular and respiratory effects, and mortality conducted in locations
where the mean annual PM2.s concentration were <17 ug/m3.
      The observations from both the short- and long-term exposure studies are supported by
experimental findings of PM25-induced subclinical and clinical cardiovascular effects.
Epidemiologic studies have shown an increase in ED visits and hospital admissions for IHD upon
exposure to PM2 5. These effects are coherent with the changes in vasomotor function and ST-
segment depression observed in both toxicological and controlled human exposure studies. It has
been postulated that exposure to PM2 5 can lead to myocardial ischemia through an effect on the
autonomic nervous system or by altering vasomotor function. PM-induced systemic inflammation,
oxidative stress and/or endothelial dysfunction may contribute to altered vasomotor function. These
effects have been demonstrated in recent animal toxicological studies, along with altered
microvascular reactivity, altered vessel tone, and reduced blood flow during ischemia. Toxicological
studies demonstrating increased right ventricular pressure and diminished cardiac contractility also
provide biological plausibility for the associations observed between PM2 5 and CHF in
epidemiologic studies.
      Thus, the overall evidence from the short-term epidemiologic, controlled human exposure, and
toxicological studies evaluated provide coherence and biological plausibility for  cardiovascular
effects related to myocardial ischemia and CHF. Coherence in the cardiovascular effects observed
can be found in long-term exposure studies, especially for CVDs among post-menopausal  women.
December 2009
                              2-15

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Additional studies provide limited evidence for subclinical measures of atherosclerosis in
epidemiologic studies with stronger evidence from toxicological studies that have demonstrated
accelerated development of atherosclerosis in ApoE"" mice exposed to PM2.5 CAPs along with
effects on coagulation, experimentally-induced hypertension, and vascular reactivity. Repeated acute
responses to PM may lead to cumulative effects that manifest as chronic disease, such as
atherosclerosis. Contributing factors to atherosclerosis development include systemic inflammation,
endothelial dysfunction, and oxidative stress all of which are associated with PM2.5 exposure.
However, it has not yet been determined whether PM initiates or promotes atherosclerosis. The
evidence from both short- and long-term exposure studies on cardiovascular morbidity provide
coherence and biological plausibility for the cardiovascular mortality  effects observed when
examining both exposure durations. In addition, cardiovascular hospital admission and mortality
studies that examined the PMi0 concentration-response relationship found evidence of a log-linear
no-threshold relationship between PM exposure and cardiovascular-related morbidity (Section 6.2)
and mortality (Section  6.5).
      Epidemiologic studies have also reported respiratory effects related to short-term exposure to
PM2.5, which include increased ED visits and hospital admissions, as well as alterations in lung
function and respiratory symptoms in asthmatic children. These respiratory effects were found to be
generally robust to the  inclusion of gaseous pollutants in copollutant models with the strongest
evidence from the higher powered studies (Figure 6-9 and Figure 6-15). Consistent positive
associations were also reported between short-term exposure to PM2 5 and respiratory mortality in
epidemiologic studies.  However, uncertainties  exist in the PM2 5-respiratory mortality associations
reported due to the limited number of studies that examined potential  confounders of the PM25-
respiratory mortality relationship, and the limited information regarding the biological plausibility of
the clinical and subclinical respiratory outcomes observed in the epidemiologic and controlled
human exposure studies (Section 6.3) resulting in the progression to PM25-induced respiratory
mortality. Important new findings, which support the PM2 5-induced respiratory effects mentioned
above, include associations with post-neonatal  (between 1 mo and 1 yr of age) respiratory mortality.
Controlled human exposure studies  provide some support for the respiratory findings from
epidemiologic studies,  with demonstrated increases in pulmonary inflammation following short-term
exposure. However, there is limited and inconsistent evidence of effects in response to controlled
exposures to PM2 5 on respiratory  symptoms or pulmonary function among healthy adults or adults
with respiratory disease. Long-term exposure epidemiologic studies provide additional evidence for
PM2^-induced respiratory morbidity, but little evidence for an association with respiratory mortality.
These epidemiologic morbidity studies have found decrements in lung function growth, as well  as
increased respiratory symptoms, and asthma. Toxicological studies provide coherence and biological
plausibility for the respiratory effects observed in response to short and long-term exposures to PM
by demonstrating a wide array of biological responses including: altered pulmonary function, mild
pulmonary inflammation and injury, oxidative  responses, and histopathological changes in animals
exposed by inhalation to PM25 derived from a wide variety of sources. In  some cases, prolonged
exposures led to adaptive responses. Important evidence was also found in an animal model for
altered lung development following pre- and post-natal exposure to urban air, which  may provide a
mechanism to  explain the reduction in lung function growth observed in children in response to
long-term exposure to PM.
      Additional respiratory-related effects have  been tied to allergic responses. Epidemiologic
studies have provided evidence for increased hospital admissions for allergic symptoms (e.g.,
allergic rhinitis) in response to short- and long-term exposure to PM2 5. Panel studies also positively
associate long-term exposure to PM2 5 and PMip with indicators of allergic sensitization. Controlled
human exposure and toxicological studies provide coherence for the exacerbation of allergic
symptoms, by  showing that PM2 5 can promote allergic responses and intensify existing allergies.
Allergic responses require repeated  exposures to antigen over time and co-exposure to an adjuvant
(possibly DE particles or UF CAPs) can enhance this response. Allergic sensitization often underlies
allergic asthma, characterized by inflammation and AHR. In this way, repeated or chronic exposures
involving multifactorial responses (immune system activation, oxidative stress, inflammation) can
lead to irreversible outcomes. Epidemiologic studies have also reported evidence for increased
hospital admissions for respiratory infections in response to both short- and long-term exposures to
PM2 5. Toxicological  studies suggest that PM impairs innate immunity, which is the first line of
defense against infection, providing coherence for the respiratory infection effects observed in
epidemiologic studies.
December 2009                                  2-16

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      The difference in effects observed across studies and between cities may be attributed, at least
in part, to the differences in PM composition across the U.S. Differences in PM toxicity may result
from regionally varying PM composition and size distribution, which in turn reflects differences in
sources and PM volatility. A person's exposure to ambient PM will also vary due to regional
differences in personal activity patterns, microenvironmental characteristics and the spatial
variability of PM concentrations in urban areas. Regional differences in PM2.5 composition are
outlined briefly in Section 2.1 above and in more detail in Section 3.5. An examination of data from
the CSN indicates that East-West gradients exist for a number of PM components. Specifically, SO42"
concentrations are higher in the East, OC constitutes a larger fraction of PM in the West, and NO3"
concentrations are highest in the valleys of central California and during the winter in the Midwest.
However, the available evidence and the limited  amount of city-specific speciated PM2.5 data does
not allow conclusions to be drawn that specifically differentiate effects of PM in different locations.
      It remains a challenge to determine relationships between specific constituents, combinations
of constituents, or sources of PM25 and the various health effects observed. Source apportionment
studies of PM2.5 have attempted to decipher some of these relationships and in the process have
identified associations between multiple sources and various respiratory and cardiovascular health
effects, as well as mortality. Although different source apportionment methods have been used across
these studies, the methods used have been evaluated and found generally to identify the same
sources and associations between sources and health effects (Section 6.6). While uncertainty
remains, it has been recognized that many sources and components of PM2 5 contribute to health
effects. Overall, the results displayed in Table 6-17 indicate that many constituents of PM25 can be
linked with multiple health effects, and the evidence is not yet sufficient to allow differentiation of
those constituents or sources that are more closely related to specific health outcomes.
      Variability in the associations observed across PM2 5 epidemiologic studies may be due in part
to exposure  error related to the use of county-level air quality data. Because western U.S. counties
tend to be much larger and more topographically diverse than eastern U.S.  counties, the day-to-day
variations in concentration at one site, or even for the average of several sites, may not correlate well
with the day-to-day variations in all parts of the county. For example, site-to-site correlations as a
function of distance between sites (Section 3.5.1.2) fall off rapidly with distance in Los Angeles, but
high correlations extend to larger distances in eastern cities such as Boston and Pittsburgh. These
differences may be attributed to a number of factors including topography,  the built environment,
climate, source characteristics, ventilation usage, and personal activity patterns. For instance,
regional differences in climate and infrastructure can affect time spent outdoors or indoors, air
conditioning usage, and personal activity patterns. Characteristics of housing stock may also cause
regional differences in effect estimates because new homes tend to have lower infiltration factors
than older homes. Biases and uncertainties in exposure estimates resulting from these aspects can, in
turn, cause bias and uncertainty in associated health effects estimates.
      The new evidence reviewed in this ISA greatly expands upon the evidence available in the
2004 PM AQCD particularly in providing greater understanding of the underlying mechanisms for
PM2 5 induced cardiovascular and respiratory effects for both short- and long-term exposures. Recent
studies have provided new evidence linking long-term exposure to PM2 5 with cardiovascular
outcomes that has expanded upon the continuum of effects ranging from the more subtle subclinical
measures to cardiopulmonary mortality.
December 2009                                  2-17

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2.3.3.  Exposure to PMi0-2.5
2.3.3.1.   Effects of Short-Term Exposure to PM10.2.5
Table 2-3.    Summary of causal determinations for short-term exposure to PMi0.2.6-
      Size Fraction
Outcome
Causality Determination
                       Cardiovascular Effects
                    Suggestive
        PMi,
                       Respiratory Effects
                    Suggestive
                       Mortality
                    Suggestive
      Cardiovascular Effects

      Generally positive associations were reported between short-term exposure to PMi0_2.5 and
hospital admissions or ED visits for cardiovascular causes. These results are supported by a large
U.S. multicity study of older adults that reported PMi0_2.5 associations with CVD hospital
admissions, and only a slight reduction in the PMi0_2.5 risk estimate when included in a copollutant
model with PM2.5 (Section 6.2.10). The PMi0_2.5 associations with cardiovascular hospital admissions
and ED visits were observed in study locations with mean 24-h avg PMi0_2.5 concentrations ranging
from 7.4 to 13 (ig/m3. These results are supported by the associations observed between PMi0_2.5 and
cardiovascular mortality in areas with 24-h avg PM10_2.5 concentrations ranging from 6.1-16.4 (ig/m3
(Section 6.2.11). The results of the epidemiologic studies were further confirmed by studies that
examined dust storm events, which contain high concentrations of crustal material, and found an
increase in cardiovascular-related ED visits and hospital admissions. Additional epidemiologic
studies have reported PMi0_2.5 associations with other cardiovascular health effects including
supraventricular ectopy and changes in HRV (Section 6.2.1.1). Although limited in number, studies
of controlled human exposures provide some evidence to support the alterations in HRV observed in
the epidemiologic studies (Section 6.2.1.2). The few toxicological studies that examined the effect of
PMio_2.5 on cardiovascular health effects used IT instillation due to the technical challenges in
exposing rodents via inhalation to PMi0_2.5, and, as a result, provide only limited evidence on the
biological plausibility of PMi0_2.5 induced cardiovascular effects. The potential for  PMi0_2.5 to elicit an
effect is supported by dosimetry studies, which show that a large proportion of inhaled particles in
the 3-6 micron (dae) range can  reach and deposit in the lower respiratory tract, particularly the
tracheobronchial (TB) airways (Figures 4-3 and 4-4). Collectively, the evidence from epidemiologic
studies, along  with the more limited evidence from controlled human exposure and toxicological
studies is suggestive of a causal relationship between short-term exposures to PMi025 and
cardiovascular effects.


      Respiratory Effects

      A number of recent epidemiologic studies conducted in Canada and France found consistent,
positive associations between respiratory ED visits and hospital admissions and short-term exposure
to PMio_2.5in studies with mean 24-h avg concentrations ranging from 5.6-16.2 ug/m3 (Section 6.3.8)
In these studies, the strongest relationships were observed among children, with less consistent
evidence for adults and older adults  (i.e., > 65). In a large multicity study of older adults, PMi0_2.5
was positively associated with respiratory hospital admissions in both single and copollutant models
with PM25. In addition,  a U.S.-based multicity study found evidence for an increase in respiratory
mortality upon short-term exposure to PM10_2.5,  but these associations have not been consistently
December 2009
          2-18

-------
observed in single-city studies (Section 6.3.9). A limited number of epidemiologic studies have
focused on specific respiratory morbidity outcomes, and found no evidence of an association with
lower respiratory symptoms, wheeze, and medication use (Section 6.3.1.1). While controlled human
exposure studies have not observed an effect on lung function or respiratory symptoms in healthy or
asthmatic adults in response to short-term exposure to PMi0_2.5, healthy volunteers have exhibited an
increase in markers of pulmonary inflammation. Toxicological studies using inhalation exposures are
still lacking, but pulmonary injury has been observed in animals after IT instillation exposure
(Section 6.3.5.3). In some cases, PMi0_2.5 was found to be more potent than PM2.5 and effects were
not attributable to endotoxin. Both rural and urban PMi0_2.5 have induced inflammation and injury
responses in rats or mice exposed via IT instillation, making it difficult to distinguish the health
effects of PM 10-2.5 from different environments. Overall, epidemiologic studies, along with the
limited number of controlled human exposure and toxicological studies that examined PMi0_2.5
respiratory effects provide evidence that is suggestive of a causal relationship between short-
term exposures to PM 10-2.5 and respiratory effects.


      Mortality

      The majority of studies evaluated in this review provide some evidence for mortality
associations with PMi0_2.5 in areas with mean 24-h avg concentrations ranging from 6.1-16.4 ug/m3.
However, uncertainty surrounds the PMi0_2.5 associations reported in the studies evaluated due to the
different methods used to estimate PMi0_2.5 concentrations across studies (e.g., direct measurement of
PM10_2.5 using dichotomous samplers, calculating the difference between PM10 and PM2.5
concentrations). In addition, only a limited number of PMi0_2.5 studies have investigated potential
confounding by gaseous copollutants or the influence of model specification on PMi0_2.5 risk
estimates.
      Anew U.S.-based multicity study, which estimated PMi0_2.5 concentrations by calculating the
difference between the county-average PMi0 and PM2.5, found associations between PMi0_2.5 and
mortality across the U.S., including evidence for regional variability in PM10_2.5 risk estimates
(Section 6.5.2.3). Additionally, the U.S.-based multicity study provides preliminary evidence for
greater effects occurring during the warmer months (i.e., spring and summer). A multicity Canadian
study provides additional evidence for an association between short-term exposure to PMio-2.5 and
mortality (Section 6.5.2.3). Although consistent positive associations have been observed across both
multi-  and single-city studies, more data are needed to adequately characterize the chemical and
biological components that may modify the potential toxicity of PMio_2.s and compare the different
methods used to estimate exposure. Overall, the evidence evaluated JS Suggestive Of 3 Causal
relationship between short-term exposures to PM,,,   and mortality.


2.3.4. Integration of PM10.2.s Effects

Epidemiologic, controlled human exposure, and toxicological studies have provided evidence that is
suggestive for relationships between short-term exposure to PMi0_2.5 and cardiovascular effects,
respiratory effects, and mortality. Conclusions regarding causation for the various health effects and
outcomes were made for PMi0_2.5 as a whole regardless of origin, since PMi0_2.5-related effects have
been demonstrated for a number of different environments (e.g., cities reflecting a wide range of
environmental conditions). Associations between short-term exposure to PMi0_2.5 and cardiovascular
and respiratory effects, and mortality have been observed in locations with mean PMi0_2.5
concentrations ranging from 5.6 to 33.2 (ig/m3, and maximumPMi0_2.5 concentrations ranging from
24.6 to 418.0 (ig/m ) (Figure 2-3). A number of different health effects are included in Figure 2-3 to
provide an integration of the range of effects by mean concentration, with a focus on cardiovascular
and respiratory effects, and mortality (i.e., health effects categories with at least a suggestive causal
determination). To date, a sufficient amount of evidence does not exist in order to draw conclusions
regarding the health effects and outcomes associated with long-term exposure to PMi0_2.5.
      In epidemiologic studies, associations between short-term exposure to PMi0_2.5 and
cardiovascular outcomes (i.e., IHD hospital admissions, supraventricular ectopy,  and changes in
HRV) have been found that are similar in magnitude to those observed in PM2.5 studies. Controlled
human exposure studies have also observed alterations in HRV, providing consistency and coherence
December 2009                                  2-19

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for the effects observed in the epidemiologic studies. To date, only a limited number of toxicological
studies have been conducted to examine the effects of PMi0_2.s on cardiovascular effects. All of these
studies involved IT instillation due to the technical challenges of using PMi0_2.5 for rodent inhalation
studies. As a result, the toxicological studies evaluated provide limited biological plausibility for the
PMio_2.5 effects observed in the epidemiologic and controlled human exposure studies.
Study
Outcome
Chen etal. (2004.087262) COPDHA
Fung etal. (2006,089789) RDHA
Chen etal. (2005. 087942) RDHA
Villeneuve et al. (2003, 055051) Nonaccidental Mortality
Lipfert et al. (2000, 004088) CVD Mortality
Peters et al. (2001 , 016546) Ml
Tolbert et al. (2007, 090316) CVD ED Visits
RD ED Visits
Klemm et al. (2003, 042801) Nonaccidental Mortality
Metzger et al. (2007, 092856) Ventricular Arrhythmia
Peel et al. (2005, 056305) Asthma ED Visits
COPD ED Visits
RD ED Visits
Pneumonia ED Visits
URI ED Visits
Metzger etal. (2004,044222) CHF ED Visits
I HD ED Visits
Klemm et al. (2004, 056585) Nonaccidental Mortality
Mar et al. (2004, 057309) Symptoms (any)
Asthma Symptoms
Lin etal. (2005. 087828) RTI HA
Burnett et al. (2004, 086247) Non-accidental Mortality
Burnett et al. (1 997, 084194) CVD HA
Respiratory HA
Fairley (2003, 042850) Nonaccidental Mortality
Zanobetti & Schwartz (2009, 188462) Nonaccidental Mortality
Lin etal. (2002. 026067) Asthma HA (boys)
Lin et al. (2002, 026067; 2004, 056067) Asthma HA (girls)
Peng et al. (2008, 156850) RD HA
CVD HA
Burnett and Goldberg (2003, 042798) Nonaccidental Mortality
Ito (2003, 042856) Nonaccidental Mortality
CHF HA
IHDHA
COPD HA
Pneumonia HA
Thurston et al. (1 994, 043921) Respiratory HA
Sheppard (2003, 042826) Asthma HA
Ostro et al. (2003, 042824) CVD Mortality
Mar et al. (2003, 042841) CVD Mortality
b Study did not present mean; median presented.
Mean3
5.6
5.6
5.6
6.1
6.9d
7.4
9.0
9.0
9.0°
9.6
9.7
9.7
9.7
9.7
9.7
9.7"
9.7d
9.9
10.8°
10.8C
10.9
11.4
11.5"
11. 5d
11.7"
11.8
12.2
12.2
12.3d
12.3"
12.6
13.3"
13.3"
13.3d
13.3"
13.3d
14.4C
16.2
30.5
33.2
Max3
24.6
27.1
24.6
72.0
28.3
50.3
50.3
30.0
50.3
34.2e
•349°
34.2e
34.2°
34.2°
34.2e
34.2°
25.2
50.9°
en oe 	
45.0
151.0
56.1
56.1
55.2
88.3°
68.0
68.0
81.3°
81 .3e
99.0
50.0
50.0
50.0
50.0
50.0
33.0
88.0
418.0
158.6
\
0,75
Effect Estimate (95% Cl)
i •

Jm-
t
•*—
-Ł_
A 1
(
I ^
Ł Ł
fe
| ,
I »
1.
J*.
L*.
L*.
I
1 I I I 1
1,00 1,25 1.50 1.75 2.00
   Mean value slightly different from those reported in the published study; mean was either
provided by study authors or calculated from data provided by study authors.
  ' Maximum PMio-25 concentration provided by study authors or calculated from data provided by
study authors.
                                                                  Relative Risk / Odds Ratio
Figure 2-3.     Summary of U.S. studies examining the association between short-term
               exposure to PMi0-2.5 and cardiovascular morbidity/mortality and respiratory
               morbidity/mortality. All effect estimates have been standardized to reflect a
               10 ug/m  increase in mean 24-h avg PMi0.2.s concentration and ordered by
               increasing concentration.

      Limited evidence is available from epidemiologic studies for respiratory health effects and
outcomes in response to short-term exposure to PMi0_2.5. An increase in respiratory hospital
admissions and ED visits has been observed, but primarily in studies conducted in Canada and
Europe. In addition, associations are not reported for lower respiratory symptoms, wheeze, or
medication use. Controlled human exposure studies have not observed an effect on lung function or
respiratory symptoms in healthy or asthmatic adults, but healthy volunteers have exhibited
pulmonary inflammation. The toxicological studies (all IT instillation) provide evidence of
December 2009
2-20

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pulmonary injury and inflammation. In some cases, PM10_2.5 was found to be more potent than PM2.5
and effects were not solely attributable to endotoxin.
      Currently, a national network is not in place to monitor PMi0_2.5 concentrations. As a result,
uncertainties surround the concentration at which the observed associations occur. Ambient
concentrations of PMi0_2.5 are generally determined by the subtraction of PMi0 and PM25
measurements, using various methods. For example, some epidemiologic studies estimate PMi0_2.5
by taking the difference between collocated PM10 and PM2.5 monitors while other studies have taken
the difference between county average PMi0 and PM2.5 concentrations. Moreover, there are potential
differences among operational flow rates and temperatures for PMi0 and PM2.5 monitors used to
calculate PMio_2.5. Therefore, there is greater error in ambient exposure to PM 10-2.5 compared  to PM25.
This would tend to increase uncertainty and make it more difficult to detect effects of PMi0_2.5 in
epidemiologic studies. In addition, the various differences between eastern and western U.S. counties
can lead to exposure misclassification, and the potential underestimation of effects in western
counties (as discussed for PM25 in Section 2.3.2).
      It is also important to note that the chemical composition of PMi0_2.5 can vary considerably by
location, but city-specific speciated PMi0_2.5 data are limited. PMi0_2.5 may contain Fe, Si, Al, and
base cations from soil, plant and insect fragments, pollen, fungal spores, bacteria, and viruses, as
well as fly  ash, brake lining particles, debris,  and automobile tire fragments.
      The 2004 PM AQCD presented the limited amount of evidence available that examined the
potential association between exposure to PMi0_2.5 and health  effects and outcomes. The current
evidence, primarily from epidemiologic studies, builds upon the results from the 2004 PM AQCD
and indicates that short-term exposure to PMi0_2.5 is associated with effects on both the
cardiovascular and respiratory systems. However, variability in the chemical and biological
composition of PMi0_2.5, limited evidence regarding effects of the various components of PMi0_2.5,
and lack of clearly defined biological mechanisms for PM10_2.5-related effects are important sources
of uncertainty.


2.3.5.  Exposure to UFPs



2.3.5.1.   Effects of Short-Term Exposure to UFPs
Table 2-4.    Summary of causal determinations for short-term exposure to UFPs.


      Size Fraction                    Outcome                        Causality Determination

                      Cardiovascular Effects                  Suggestive
UFPs                  	
                      Respiratory Effects                    Suggestive
      Cardiovascular Effects

      Controlled human exposure studies provide the majority of the evidence for cardiovascular
health effects in response to short-term exposure to UFPs. While there are a limited number of
studies that have examined the association between UFPs and cardiovascular morbidity, there is a
larger body of evidence from studies that exposed subjects to fresh DE, which is typically dominated
by UFPs. These studies have consistently demonstrated changes in vasomotor function following
exposure to atmospheres containing relatively high concentrations of particles (Section 6.2.4.2).
Markers of systemic oxidative stress have also been observed to increase after exposure to various
particle types that are predominantly in the UFP size range. In addition, alterations in HRV
parameters have been observed in response to controlled human exposure to UF CAPs, with
inconsistent evidence for changes in markers of blood coagulation following exposure to UF CAPs
December 2009                                  2-21

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and DE (Sections 6.2.1.2 and 6.2.8.2). A few toxicological studies have also found consistent
changes in vasomotor function, which provides coherence with the effects demonstrated in the
controlled human exposure studies (Section 6.2.4.3). Additional UFP-induced effects observed in
toxicological studies include alterations in HRV, with less consistent effects observed for systemic
inflammation and blood coagulation. Only a few epidemiologic studies have examined the effect of
UFPs on cardiovascular morbidity and collectively they found inconsistent evidence for an
association between UFPs and CVD hospital admissions, but some positive associations for
subclinical cardiovascular measures (i.e., arrhythmias and supraventricular beats) (Section 6.2.2.1).
These studies were conducted in the U.S. and Europe in areas with mean particle number
concentration ranging from -8,500 to 36,000 particles/cm3. However, UFP number concentrations
are highly variable  (i.e., concentrations drop off quickly from the road compared to accumulation
mode particles), and therefore, more subject to exposure error than accumulation mode particles. In
conclusion, the evidence from the studies evaluated JS Suggestive Of 3 C3USal relationship
between short-term exposures to UFPs and cardiovascular effects.


      Respiratory Effects

      A limited number of epidemiologic studies have examined the potential association between
short-term exposure to UFPs and respiratory morbidity.  Of the studies evaluated, there is limited, and
inconsistent evidence for an association between short-term exposure to UFPs and respiratory
symptoms, as well  as asthma hospital admissions in locations a median particle number
concentration of-6,200 to a mean of 38,000 particles/cm3 (Section 6.3.10). The spatial and temporal
variability of UFPs also affects  these associations. Toxicological studies have reported respiratory
effects including oxidative, inflammatory, and allergic responses using a number of different UFP
types (Section 6.3). Although controlled human exposure studies have not extensively examined the
effect of UFPs on respiratory outcomes, a few studies have observed small UFP-induced
asymptomatic  decreases in pulmonary function.  Markers of pulmonary inflammation have been
observed to increase in  healthy  adults following controlled exposures to UFPs, particularly in studies
using fresh DE. However, it is important to note that for both controlled human exposure and animal
toxicological studies of exposures to fresh DE, the relative contributions of gaseous copollutants to
the respiratory effects observed remain unresolved. Thus, the current collective evidence JS
suggestive of a causal relationship between short-term exposures to UFPs and
respiratory effects.
2.3.6.  Integration of UFP  Effects
      The controlled human exposure studies evaluated have consistently demonstrated effects on
vasomotor function and systemic oxidative stress with additional evidence for alterations in HRV
parameters in response to exposure to UF CAPs. The toxicological studies provide coherence for the
changes in vasomotor function observed in the controlled human exposure studies. Epidemiologic
studies are limited because a national network is not in place to measure UFP in the U.S. UFP
concentrations are spatially and temporally variable, which would increase uncertainty and make it
difficult to detect associations between health effects and UFPs in epidemiologic studies. In addition,
data on the composition of UFPs, the spatial and temporal evolution of UFP size distribution and
chemical composition, and potential  effects of UFP constituents are sparse.
      More limited evidence is available regarding the effect of UFPs on respiratory effects.
Controlled human exposure studies have not extensively examined the effect of UFPs on respiratory
measurements, but a few studies have observed small decrements in pulmonary function and
increases in pulmonary inflammation. Additional effects including oxidative, inflammatory, and pro-
allergic outcomes have been demonstrated in toxicological studies. Epidemiologic studies have
found limited and inconsistent evidence for associations between UFPs and respiratory effects.
      Overall, a limited number of studies have examined the association between exposure to UFPs
and morbidity and mortality. Of the studies evaluated, controlled human exposure and toxicological
studies provide the most evidence for UFP-induced cardiovascular and respiratory effects; however,
many studies focus on exposure to DE. As a result, it is  unclear if the effects observed are due to
UFP, larger particles (i.e., PM2.s), or the gaseous components of DE. Additionally, UF CAPs systems
December 2009                                 2-22

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are limited as the atmospheric UFP composition is modified when concentrated, which adds
uncertainty to the health effects observed in controlled human exposure studies (Section 1.5.3).


2.4.  Policy Relevant Considerations
2.4.1.  Potentially Susceptible Populations

      Upon evaluating the association between short- and long-term exposure to PM and various
health outcomes, studies also attempted to identify populations that are more susceptible to PM (i.e.,
populations that have a greater likelihood of experiencing health effects related to exposure to an air
pollutant (e.g., PM) due to a variety of factors including, but not limited to: genetic or developmental
factors, race, gender, life stage, lifestyle (e.g., smoking status and nutrition) or preexisting disease; as
well as, population-level factors that can increase an individual's exposure to an air pollutant (e.g.,
PM) such as socioeconomic status [SES], which encompasses reduced access to health care,  low
educational attainment, residential location, and other factors). These studies did so by conducting
stratified analyses; by  examining effects in individuals with an underlying health condition; or by
developing animal models that mimic the pathophysiologic conditions associated with an adverse
health effect. In addition, numerous studies that focus on  only one potentially susceptible population
provide supporting evidence on  whether a population is susceptible to PM exposure. These studies
identified a multitude of factors  that could potentially contribute to whether an individual is
susceptible to PM (Table 8-2). Although studies have primarily used exposures to PM2.5 or PMi0, the
available evidence suggests that the identified factors may also enhance susceptibility to PMi0_2.5.
The examination of susceptible populations to PM exposure allows for the NAAQS to provide an
adequate margin of safety for both the general population and for susceptible populations.
      During specific  periods  of life (i.e., childhood and advanced age), individuals may be more
susceptible to environmental exposures, which in turn can render them more susceptible to PM-
related health effects. An evaluation of age-related health effects suggests that older adults have
heightened responses for cardiovascular morbidity with PM exposure. In addition, epidemiologic
and toxicological studies provide evidence that indicates children are at an increased risk of PM-
related respiratory effects.  It should be noted that the health effects observed in children could be
initiated by exposures  to PM that occurred during key windows of development, such as in utero.
Epidemiologic studies that focus on exposures during development have reported inconsistent
findings (Section 7.4), but a recent toxicological study suggests that inflammatory responses in
pregnant women due to exposure to PM could result in health effects in the developing fetus.
      Epidemiologic studies have also examined whether additional factors, such as gender,  race, or
ethnicity modify the association between PM and morbidity and mortality outcomes. Although
gender and race do not seem to modify PM risk estimates, limited evidence from two studies
conducted in California suggest that Hispanic ethnicity may modify the association between  PM and
mortality.
      Recent epidemiologic and toxicological studies provided evidence that individuals with null
alleles or polymorphisms in genes that mediate the antioxidant response to oxidative stress (i.e.,
GSTM1), regulate enzyme activity (i.e., MTHFR and cSHMT), or regulate levels of procoagulants
(i.e., fibrinogen) are more susceptible to PM exposure. However, some studies have shown that
polymorphisms in genes (e.g., HFE) can have a protective effect against effects of PM exposure.
Additionally, preliminary evidence suggests that PM exposure can impart epigenetic effects (i.e.,
DNA methylation); however, this requires further investigation.
      Collectively, the evidence from epidemiologic and toxicological, and to  a lesser extent,
controlled human exposure studies, indicate increased susceptibility of individuals with underlying
CVDs and respiratory  illnesses (i.e., asthma) to PM exposure. Controlled human exposure and
toxicological studies provide additional evidence for increased PM-related cardiovascular effects in
individuals with underlying respiratory health conditions.
      Recently studies have begun to examine the influence of preexisting chronic inflammatory
conditions, such as diabetes and obesity, on PM-related health effects. These studies have found
some evidence for increased associations for cardiovascular outcomes along with pathophysiologic
alterations in markers  of inflammation, oxidative stress, and acute phase response. However, more
December 2009                                  2-23

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research is needed to thoroughly examine the affect of PM exposure on obese individuals and to
identify the biological pathway(s) that could increase the susceptibility of diabetic and obese
individuals to PM.
      There is also evidence that SES, measured using surrogates such as educational attainment or
residential location, modifies the association between PM and morbidity  and mortality outcomes. In
addition, nutritional status, another surrogate measure of SES, has been shown to have protective
effects against PM exposure in individuals that have a higher intake of some vitamins and nutrients.
      Overall, the epidemiologic, controlled human exposure, and toxicological studies evaluated in
this review provide evidence for increased susceptibility for various populations, including children
and older adults, people with pre-existing cardiopulmonary diseases, and people with lower SES.


2.4.2.  Lag  Structure of PM-Morbidity and PM-Mortality Associations

      Epidemiologic studies have evaluated the time-frame in which exposure to PM can impart a
health effect. PM exposure-response relationships can potentially be influenced by a multitude of
factors, such as the underlying susceptibility of an individual (e.g., age, pre-existing diseases), which
could increase or decrease the lag times observed.
      An attempt has been made to identify whether certain lag periods are more strongly associated
with specific health outcomes. The epidemiologic evidence evaluated in the 2004 PM AQCD
supported the use of lags of 0-1 days for cardiovascular effects and longer moving averages or
distributed lags for respiratory diseases (U.S. EPA, 2004, 056905). However, currently, little
consensus exists as to the most appropriate a priori lag times to use when examining morbidity and
mortality outcomes. As a result,  many investigators have chosen to examine the lag structure of
associations between PM concentration and health outcome instead of focusing on a priori lag times.
This approach is informative because if effects are cumulative, higher overall risks may exist than
would be observed for any given single-day lag.


2.4.2.1.   PM-Cardiovascular Morbidity Associations

      Most of the studies evaluated that examined the association between cardiovascular hospital
admissions and ED visits report  associations with short-term PM exposure at lags 0- to 2-days, with
more limited evidence for snorter durations (i.e., hours) between exposure and response for some
health effects (e.g., onset of MI) (Section 6.2.10). However, these studies have rarely examined
alternative lag structures. Controlled human exposure and toxicological studies provide biological
plausibility for the health effects observed in the epidemiologic studies at immediate or concurrent
day lags. Although the majority of the evidence supports shorter lag times for cardiovascular health
effects, a recent study has provided preliminary evidence suggesting that longer lag times (i.e., 14-
day distributed lag model) may be plausible for non-ischemic cardiovascular conditions
(Section 6.2.10). Panel studies of short-term exposure to PM and cardiovascular endpoints have  also
examined the time frame from exposure to health effect using a wide range of lag times.  Studies of
ECG changes indicating ischemia show effects at lags from several hours to 2 days, while lag times
ranging from hours to  several week moving averages have been observed in studies of arrhythmias,
vasomotor function and blood markers of inflammation, coagulation and oxidative stress
(Section 6.2). The longer lags observed in these panel studies may be explained if the effects of PM
are cumulative. Although few studies of cumulative effects have been conducted, toxicological
studies have demonstrated PM-dependent progression of atherosclerosis. It should be noted that PM
exposure could also lead to an acute event (e.g., infarction or stroke) in individuals with
atherosclerosis that may have progressed in response to cumulative PM exposure. Therefore, effects
have been observed at a range of lag periods from a few hours to several  days with no clear evidence
for any lag period having stronger associations then another.


2.4.2.2.   PM-Respiratory Morbidity Associations

      Generally, recent studies of respiratory hospital admissions that evaluate multiple lags, have
found effect sizes to be larger when using longer moving averages or distributed lag models. For
example, when examining hospital admissions for all respiratory diseases among older adults, the
strongest associations were observed when using PM concentrations 2 days prior to the hospital
December 2009                                 2-24

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admission (Section 6.3.8). Longer lag periods were also found to be most strongly associated with
asthma hospital admissions and ED visits in children (3-5 days) with some evidence for more
immediate effects in older adults (lags of 0 and 1 day), but these observations were not consistent
across studies (Section 6.3.8). These variable results could be due to the biological complexity of
asthma, which inhibits the identification of a specific lag period. The longer lag times identified in
the epidemiologic studies evaluated are biologically plausible considering that PM effects on allergic
sensitization and lung immune defenses have been observed in controlled human exposure and
toxicological studies. These effects could lead to respiratory illnesses over a longer time course (e.g.,
within several days respiratory infection may become evident, resulting in respiratory symptoms or a
hospital admission). However, inflammatory responses, which contribute to some forms of asthma,
may result in symptoms requiring medical care within a shorter time frame (e.g., 0-1 days).


2.4.2.3.   PM-Mortality Associations

      Epidemiologic studies that focused on the association between short-term PM exposure and
mortality (i.e., all-cause, cardiovascular, and respiratory) mostly examined a priori lag structures of
either 1 or 0-1 days. Although mortality studies do not often examine alternative lag structures, the
selection of the aforementioned a priori lag days has been confirmed in additional studies, with the
strongest PM-mortality associations consistently being observed at lag 1 and 0-1-days (Section 6.5).
However, of note is recent evidence for larger effect estimates when using a distributed lag model.
      Epidemiologic studies that examined the association between long-term exposure to PM and
mortality have also attempted to identify the latency period from PM exposure to death
(Section 7.6.4). Results of the lag comparisons from several cohort studies indicate that the effects of
changes in exposure on mortality are  seen within five years, with the strongest evidence for effects
observed within the first two years. Additionally, there is evidence, albeit from one study, that the
mortality effect had larger cumulative effects spread over the follow-up year and three preceding
years.


2.4.3.  PM Concentration-Response Relationship

      An important consideration in characterizing the PM-morbidity and mortality association  is
whether the concentration-response relationship is linear across the full concentration range that is
encountered or if there are concentration ranges where there are departures from linearity
(i.e., nonlinearity). In this ISA studies have been identified that attempt to characterize the shape of
the concentration-response curve along with possible PM "thresholds" (i.e., levels which PM
concentrations must exceed in order to elicit a health response). The epidemiologic studies evaluated
that examined the shape of the concentration-response curve and the potential presence of a
threshold have focused on cardiovascular hospital admissions and ED visits and mortality associated
with short-term exposure to PMi0 and mortality associated with long-term exposure to PM2.5.
      A limited number of studies have been identified that examined the shape of the PM-
cardiovascular hospital admission and ED visit concentration-response relationship. Of these studies,
some conducted an exploratory analysis during model selection to determine if a linear curve most
adequately represented the concentration-response relationship; whereas, only one study conducted
an extensive analysis to examine the shape of the concentration-response curve at different
concentrations (Section 6.2.10.10). Overall, the limited evidence from the studies evaluated supports
the use of a no-threshold, log-linear model, which is consistent with the observations made in studies
that examined the PM-mortality relationship.
      Although multiple studies have previously examined the PM-mortality concentration-response
relationship and whether a threshold exists, more complex statistical analyses continue to be
developed to analyze this association. Using a variety of methods and models, most of the studies
evaluated support the use of a no-threshold, log-linear model; however, one study did observe
heterogeneity in the shape of the concentration-response curve across cities (Section 6.5). Overall,
the studies evaluated further support the use of a no-threshold log-linear model, but additional issues
such as the influence of heterogeneity in estimates between cities, and the effect of seasonal and
regional differences in PM on the concentration-response relationship still require further
investigation.
December 2009                                  2-25

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      In addition to examining the concentration-response relationship between short-term exposure
to PM and mortality, Schwartz et al. (2008, 156963) conducted an analysis of the shape of the
concentration-response relationship associated with long-term exposure to PM. Using a variety of
statistical  methods, the concentration-response curve was found to be indistinguishable from linear,
and, therefore, little evidence was observed to suggest that a threshold exists in the association
between long-term exposure to PM2.5 and the risk of death (Section 7.6).


2.4.4.  PM Sources and Constituents Linked to Health Effects

      Recent epidemiologic, toxicological, and controlled human exposure studies have evaluated
the health effects associated with ambient PM constituents and sources, using a variety of
quantitative methods applied to a broad set of PM constituents, rather than selecting a few
constituents a priori (Section 6.6). There is some evidence for trends  and patterns that link particular
ambient PM constituents or sources with specific health outcomes, but there is insufficient evidence
to determine whether these patterns are consistent or robust.
      For cardiovascular effects, multiple outcomes have been linked to a PM2 5 crustal/soil/road
dust source, including cardiovascular mortality and ST-segment changes. Additional studies have
reported associations between other sources (i.e., traffic and wood smoke/vegetative burning) and
cardiovascular outcomes (i.e., mortality and ED visits). Studies that only examined the effects of
individual PM2.5 constituents found evidence for an association between EC and cardiovascular
hospital admissions and cardiovascular mortality. Many studies have also observed associations
between other sources (i.e., salt, secondary SO4  "/long-range transport, other metals) and
cardiovascular effects, but at this time, there does not appear to be a consistent trend or pattern of
effects for those factors.
      There is less consistent evidence for associations between PM  sources and respiratory health
effects,  which may be partially due to the fact that fewer source apportionment studies have been
conducted that examined respiratory-related outcomes (e.g., hospital  admissions) and measures (e.g.,
lung function). However, there is some  evidence for associations between respiratory ED visits and
decrements in lung function with secondary SO42~ PM2.5. In addition, crustal/soil/road dust and
traffic sources of PM have been found to be associated with increased respiratory symptoms in
asthmatic  children and decreased PEF in asthmatic adults. Inconsistent results were observed in
those  PM2 5 studies that used individual constituents to examine associations with respiratory
morbidity and mortality, although Cu, Pb, OC, and Zn were related to respiratory health  effects in
two or more studies.
      A few studies have identified PM2 5 sources associated with total mortality. These studies
found an association between mortality and the PM2 5 sources: secondary SO4 /long-range transport,
traffic, and salt. In addition, studies have evaluated whether the variation in associations between
PM2 5 and mortality or PM10 and mortality reflects differences  in PM2 5 constituents. PM10-mortality
effect estimates were greater in areas with a higher proportion of Ni in  PM2 5, but the overall PMi0-
mortality association was diminished when New York City was excluded in sensitivity analyses in
two of the studies. V was also found to modify PMio-mortality effect estimates. When examining the
effect of species-to-PM2 5 mass proportion on PM2 5-mortality effect estimates, Ni, but not V, was
also found to modify the association.
      Overall, the results indicate that many constituents of PM can be linked with differing health
effects and the evidence is not yet sufficient to allow differentiation of those constituents or sources
that are  more closely related to specific health outcomes. These findings are consistent with the
conclusions of the 2004 PM AQCD (U.S. EPA, 2004, 056905) (i.e., that a number of source types,
including  motor vehicle emissions, coal combustion, oil burning, and vegetative burning, are
associated with health effects). Although the crustal factor of fine particles was not associated with
mortality in the 2004 PM AQCD (U.S. EPA, 2004, 056905). recent studies have suggested that PM
(both  PM2 5 and PMi0_2.5) from crustal, soil or road dust sources or PM tracers linked to these sources
are associated with cardiovascular effects. In addition, PM25 secondary SO42~has been associated
with both  cardiovascular and respiratory effects.
December 2009                                  2-26

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2.5.  Welfare  Effects

      This section presents key conclusions and scientific judgments regarding causality for welfare
effects of PM as discussed in Chapter 9. The effects of particulate NOX and SOX have recently been
evaluated in the ISA for Oxides of Nitrogen and Sulfur - Ecological Criteria (U.S. EPA, 2008,
157074). That ISA focused on the effects from deposition of gas- and particle-phase pollutants
related to ambient NOX and SOX concentrations that can lead to acidification and nutrient
enrichment.  Thus, emphasis in Chapter 9 is placed on the effects of airborne PM, including NOX and
SOX, on visibility and climate, and on the effects of deposition of PM constituents other than NOX
and SOX, primarily metals and carbonaceous compounds.  EPA's framework for causality, described
in Chapter 1, was applied and the causal determinations are highlighted.
Table 2-5.    Summary of causality determination for welfare effects.
                Welfare Effects
                Causality Determination
Effects on Visibility
Causal
Effects on Climate
Causal
Ecological Effects
Likely to be causal
Effects on Materials
Causal
2.5.1.  Summary of Effects on Visibility

      Visibility impairment is caused by light scattering and absorption by suspended particles and
gases. There is strong and consistent evidence that PM is the overwhelming source of visibility
impairment in both urban and remote areas. EC and some crustal minerals are the only commonly
occurring airborne particle components that absorb light. All particles scatter light, and generally
light scattering by particles is the largest of the four light extinction components (i.e., absorption and
scattering by gases and particles). Although a larger particle scatters more light than a similarly
shaped smaller particle of the same composition, the light scattered per unit of mass is greatest for
particles with diameters from -0.3-1.0 um.
      For studies where detailed data on particle composition by size are available, accurate
calculations of light extinction can be made. However, routinely available PM speciation data can be
used to make reasonable estimates of light extinction using relatively simple algorithms that multiply
the concentrations  of each of the major PM species by its dry extinction efficiency and by a water
growth term that accounts for particle size change as a function of relative humidity for hygroscopic
species (e.g., sulfate, nitrate, and sea salt). This permits the visibility impairment associated with
each of the major PM components to be separately  approximated from PM speciation monitoring
data.
      Direct optical measurement of light extinction measured by transmissometer, or by combining
the PM light scattering measured by integrating nephelometers with the PM light absorption
measured by an aethalometer, offer a number of advantages compared to  algorithm estimates of light
extinction based on PM composition and  relative humidity data. The direct measurements are not
subject to the uncertainties associated with assumed scattering and absorption efficiencies used in the
PM algorithm approach. The direct measurements have higher time resolution (i.e., minutes to
hours), which is more commensurate with visibility effects compared with calculated light extinction
using routinely available PM speciation data (i.e., 24-h duration).
      Particulate sulfate and nitrate have  comparable light extinction efficiencies (haze impacts  per
unit mass concentration) at any relative humidity value. Their light scattering per unit mass
concentration increases with increasing relative humidity, and at sufficiently high humidity values
(RH>85%) they are the most efficient particulate species contributing to haze. Particulate sulfate is
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the dominant source of regional haze in the eastern U.S. (>50% of the participate light extinction)
and an important contributor to haze elsewhere in the country (>20% of particulate light extinction).
Particulate nitrate is a minor component of remote-area regional haze in the non-California western
and eastern U.S., but an important contributor in much of California and in the upper Midwestern
U.S., especially during winter when it is the dominant contributor to particulate light extinction.
      EC and OC have the highest dry extinction efficiencies of the major PM species and are
responsible for a large fraction of the haze, especially in the northwestern U.S., though absolute
concentrations are as high in the eastern U.S.  Smoke plume impacts from large wildfires dominate
many of the worst haze periods in the western U.S. Carbonaceous PM is generally the largest
component of urban excess PM2.5 (i.e., the difference between urban and regional background
concentration). Western urban areas have more than twice the average concentrations of
carbonaceous PM than remote areas sites in the same region. In eastern urban areas PM2.5 is
dominated by about equal concentrations of carbonaceous and sulfate components, though the
usually high relative humidity in the East causes the hydrated sulfate particles to be responsible for
about twice as much of the urban haze as that caused by the carbonaceous PM.
      PM2.5 crustal material (referred to as fine soil) and PMi0_2.s are significant contributors to  haze
for remote areas sites in the arid southwestern U.S. where they contribute a quarter to a third of the
haze, with PMi0_2.s usually contributing twice that of fine soil. Coarse mass concentrations are as
high in the Central Great Plains as in the deserts though there are no corresponding high
concentrations of fine soil as in the Southwest. Also the relative contribution to haze by the high
coarse mass in the Great Plains is much smaller because of the generally higher haze values caused
by the high concentrations of sulfate and nitrate PM in that region.
      Visibility has direct significance to people's enjoyment of daily activities and their overall
sense of wellbeing. For example,  psychological research has demonstrated that people are
emotionally affected by poor VAQ such that their overall sense of wellbeing is diminished. Urban
visibility has  been examined in two types of studies directly relevant to the NAAQS review process:
urban visibility preference studies and urban visibility valuation  studies. Both types of studies are
designed to evaluate individuals' desire for good VAQ where they live, using different metrics.
Urban visibility preference studies examine individuals' preferences by investigating the amount of
visibility degradation considered unacceptable, while economic studies examine the value an
individual places on improving VAQ by eliciting how much the individual would be willing to  pay
for different amounts of VAQ improvement.
      There are three urban visibility preference studies and two additional pilot studies that have
been conducted to date that provide useful information on individuals' preferences for good VAQ in
the urban setting. The completed studies were conducted in Denver, Colorado, two cities in British
Columbia, Canada, and Phoenix, AZ. The additional studies were conducted in Washington, DC. The
range of median preference values for an acceptable amount of visibility degradation from the 4
urban areas was approximately 19-33  dv. Measured in terms of visual range (VR), these median
acceptable values were between approximately 59 and 20 km.
      The economic importance of urban visibility has been examined by a number of studies
designed to quantify the benefits (or willingness to pay) associated with potential improvements in
urban visibility. Urban visibility valuation research was described in the 2004 PM AQCD (U.S. EPA,
2004, 056905) and the 2005 PM Staff Paper (U.S. EPA, 2005, 090209). Since the mid-1990s, little
new information has become available regarding urban visibility valuation (Section 9.2.4).
      Collectively, the evidence is sufficient to conclude that 3 C3USal relationship exists
between  PM and visibility impairment.


2.5.2.  Summary of Effects on Climate

      Aerosols affect climate through direct and indirect effects. The direct effect is primarily
realized as planet brightening when seen from space because most aerosols scatter most of the
visible spectrum light that reaches them. The Intergovernmental  Panel on Climate Change (IPCC)
Fourth Assessment Report (AR4) (IPCC, 2007, 092765). hereafter IPCC AR4, reported that the
radiative forcing from this direct effect was -0.5 (±0.4) W/m2 and identified the level of scientific
understanding of this effect as 'Medium-low'.  The global mean direct radiative forcing effect from
individual components of aerosols was estimated for the first time in the IPCC AR4 where they were
reported to be (all in W/m2 units):  -0.4 (±0.2)  for sulfate, -0.05 (±0.05) for fossil fuel-derived organic
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carbon, +0.2 (±0.15) for fossil fuel-derived black carbon (BC), +0.03 (±0.12) for biomass burning,
-0.1 (±0.1) for nitrates, and -0.1 (±0.2) for mineral dust. Global loadings of anthropogenic dust and
nitrates remain very troublesome to estimate, making the radiative forcing estimates for these
constituents particularly  uncertain.
      Numerical modeling of aerosol effects on climate has sustained remarkable progress since the
time of the 2004 PM AQCD (U.S. EPA, 2004, 056905). PM AQCD, though model solutions still
display large heterogeneity in their estimates of the direct radiative forcing effect from
anthropogenic aerosols. The clear-sky direct radiative forcing over ocean due to anthropogenic
aerosols is estimated from satellite instruments to be on the order of-1.1 (±0.37) W/m2 while model
estimates are -0.6 W/m2. The models' low bias over ocean is carried through for the global average:
global average direct radiative forcing from anthropogenic aerosols is estimated from measurements
to range from -0.9 to -1.9 W/m2, larger than the estimate of-0.8 W/m2 from the models.
      Aerosol  indirect effects on climate are primarily realized as an increase in cloud brightness
(termed the 'first indirect' or Twomey effect), changes in precipitation, and possible changes in cloud
lifetime. The IPCC AR4 reported that the radiative forcing from the Twomey effect was -0.7 (range:
-1.1 to +4) and identified the level of scientific understanding of this effect as "Low" in part owing
to the very large unknowns concerning aerosol size distributions and important interactions  with
clouds. Other indirect effects from aerosols are not considered to be radiative forcing.
      Taken together, direct and indirect effects from aerosols increase Earth's shortwave albedo or
reflectance thereby reducing the radiative flux reaching the surface from the Sun. This produces net
climate cooling from aerosols. The current scientific consensus reported by IPCC AR4  is that the
direct and indirect radiative forcing from anthropogenic aerosols computed at the top of the
atmosphere, on a global  average, is about -1.3 (range: -2.2 to -0.5) W/m2. While the overall  global
average effect  of aerosols at the top of the atmosphere and at the surface is negative, absorption and
scattering by aerosols within the atmospheric column warms the atmosphere between the Earth's
surface and top of the atmosphere. In part, this is owing to differences in the distribution of aerosol
type and size within the vertical  atmospheric column since aerosol type and size distributions
strongly affect the aerosol scattering and reradiation efficiencies at different altitudes and
atmospheric temperatures. And,  although the magnitude of the overall negative radiative forcing at
the top of the atmosphere appears large in comparison to the analogous IPCC AR4 estimate of
positive radiative forcing from anthropogenic GHG of about +2.9 (± 0.3) W/m2, the horizontal,
vertical, and temporal distributions and the physical lifetimes of these two very different radiative
forcing agents  are not similar; therefore, the effects do not simply off-set one another.
      Overall, the evidence is sufficient to conclude that 3 C3USal relationship exists between
PM and effects on climate, including both direct effects on radiative forcing and indirect
effects that involve cloud feedbacks that influence precipitation formation and cloud
lifetimes.


2.5.3. Summary  of  Ecological Effects of PM

      Ecological effects  of PM include direct effects to metabolic processes of plant foliage;
contribution to total metal loading resulting in alteration of soil biogeochemistry and microbiology,
plant growth and animal growth and reproduction; and contribution to total organics loading
resulting in bioaccumulation and biomagnification across trophic levels. These effects were well-
characterized in the 2004 PM AQCD (U.S.  EPA, 2004, 056905). Thus, the summary below builds
upon the conclusions provided in that review.
      PM deposition comprises a heterogeneous mixture of particles differing in origin, size, and
chemical composition. Exposure to a given concentration of PM may, depending on the mix of
deposited particles, lead  to a variety  of phytotoxic responses and ecosystem effects. Moreover, many
of the ecological effects  of PM are due to the chemical constituents (e.g., metals, organics, and ions)
and their contribution to total loading within an ecosystem.
      Investigations of the direct effects of PM deposition on foliage have suggested little or no
effects on foliar processes, unless deposition levels were higher than is typically found  in the
ambient environment. However, consistent and coherent evidence of direct effects  of PM has been
found in heavily polluted areas adjacent to industrial point sources such as limestone quarries,
cement kilns, and metal smelters (Sections 9.4.3 and 9.4.5.7). Where toxic responses have been
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documented, they generally have been associated with the acidity, trace metal content, surfactant
properties, or salinity of the deposited materials.
      An important characteristic of fine particles is their ability to affect the flux of solar radiation
passing through the atmosphere, which can be considered in both its direct and diffuse components.
Foliar interception by canopy elements occurs for both up- and down-welling radiation. Therefore,
the effect of atmospheric PM on atmospheric turbidity influences canopy processes both by radiation
attenuation and by changing the efficiency of radiation interception in the canopy through
conversion of direct to diffuse radiation. Crop yields can be sensitive to the amount of radiation
received, and crop losses have been attributed to increased regional haze in some areas of the world
such as China (Section 9.4.4). On the other hand, diffuse radiation is more uniformly distributed
throughout the canopy and may increase canopy photosynthetic productivity by distributing radiation
to lower leaves. The enrichment in photosynthetically active radiation (PAR) present in diffuse
radiation may offset a portion of the effect of an increased atmospheric albedo due to atmospheric
particles. Further research is needed to determine the effects of PM alteration of radiative flux on the
growth of vegetation in the U.S.
      The deposition of PM onto vegetation and soil, depending on its chemical composition, can
produce responses within an ecosystem. The ecosystem response to pollutant deposition is a direct
function of the level of sensitivity of the ecosystem and its ability to ameliorate resulting change.
Many of the most important ecosystem effects of PM deposition occur in the soil. Upon  entering the
soil environment, PM pollutants can alter ecological processes of energy flow and nutrient cycling,
inhibit nutrient uptake, change ecosystem structure, and affect ecosystem biodiversity. The soil
environment is one of the most dynamic sites of biological interaction in nature. It is inhabited by
microbial  communities of bacteria, fungi, and actinomycetes,  in addition to plant roots and soil
macro-fauna. These organisms are essential participants in the nutrient cycles that make  elements
available for plant uptake. Changes in the soil environment can be important in determining plant
and ultimately ecosystem response to PM inputs.
      There is strong and consistent evidence from field and laboratory experiments that metal
components of PM alter numerous aspects of ecosystem structure and function. Changes in the soil
chemistry, microbial communities and nutrient cycling, can result from the deposition of trace
metals. Exposures to trace metals are highly variable, depending on whether deposition is by wet or
dry processes. Although metals can cause phytotoxicity at high concentrations, few heavy metals
(e.g., Cu, Ni, Zn) have been documented to cause direct phytotoxicity under field conditions.
Exposure to coarse particles and elements such as Fe and Mg  are more likely to occur via dry
deposition, while fine particles, which are more often deposited by wet deposition, are more likely to
contain elements such as Ca, Cr, Pb, Ni, and V. Ecosystems immediately downwind of major
emissions sources can receive locally heavy deposition inputs. Phytochelatins produced by plants  as
a response to sublethal concentrations of heavy metals are indicators of metal stress to plants.
Increased  concentrations of phytochelatins across regions and at greater elevation have been
associated with increased amounts of forest injury in the northeastern U.S.
      Overall, the ecological evidence is sufficient to conclude that a Causal relationship JS likely
to exist between deposition of PM and a variety of effects on individual organisms and
ecosystems, based on information from the previous review and limited new findings in
this  review. However, in many cases, it is difficult to characterize the nature and magnitude of
effects and to quantify relationships between ambient concentrations of PM and ecosystem response
due to significant data gaps and uncertainties as well as considerable variability that exists in the
components of PM and their various ecological effects.


2.5.4.  Summary of Effects on Materials

      Building materials (metals, stones, cements,  and paints) undergo natural weathering processes
from exposure to environmental elements (wind, moisture, temperature fluctuations, sunlight, etc.).
Metals form a protective film of oxidized  metal (e.g., rust) that slows environmentally induced
corrosion. However, the natural process of metal corrosion is enhanced by exposure to
anthropogenic pollutants. For example, formation of hygroscopic salts increases the duration of
surface wetness and enhances corrosion.
      A significant detrimental effect of particle pollution is the soiling of painted surfaces and other
building materials. Soiling changes the reflectance of opaque materials and reduces the transmission
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of light through transparent materials. Soiling is a degradation process that requires remediation by
cleaning or washing, and, depending on the soiled surface, repainting. Particulate deposition can
result in increased cleaning frequency of the exposed surface and may reduce the usefulness of the
soiled material.
      Attempts have been made to quantify the pollutant exposure levels at which materials damage
and soiling have been perceived. However, to date, insufficient data are available to advance the
knowledge regarding perception thresholds with respect to pollutant concentration, particle size, and
chemical composition. Nevertheless, the evidence is sufficient to conclude that 3 C3US3I
relationship exists between PM and effects on materials.



2.6.  Summary of Health  Effects  and Welfare Effects

Causal Determinations

This chapter has provided an overview of the underlying evidence used in making the causal
determinations for the health and welfare effects and PM size fractions evaluated. This review builds
upon the main conclusions of the last PM AQCD (U.S.  EPA, 2004, 056905):

       •   "A growing body of evidence both from epidemiological and toxicological studies...
           supports the general conclusion that PM2.5 (or one or more PM2.5 components), acting
           alone and/or in combination with gaseous copollutants, are likely causally related to
           cardiovascular and respiratory mortality and morbidity." (pg 9-79)

       •   "A much more limited body of evidence is suggestive of associations between short-term
           (but not long-term) exposures to ambient coarse-fraction thoracic particles... and various
           mortality and morbidity effects observed at times in some locations. This suggests that
           PMio_2.5, or some constituent component(s)  of PMi0_2.5, may contribute under some
           circumstances to increased human health risks...  with somewhat stronger evidence for...
           associations with morbidity  (especially respiratory) endpoints than for mortality." (pg
           9-79 and 9-80)

       •   "Impairment of visibility in rural  and urban areas is directly related to ambient
           concentrations of fine particles, as modulated by particle composition, size, and
           hygroscopic characteristics,  and by  relative humidity." (pg 9-99)

       •   "Available evidence, ranging from satellite to in situ measurements of aerosol effects on
           incoming solar radiation and cloud properties, is strongly indicative of an important role
           in climate for aerosols, but this role is still poorly quantified." (pg 9-111)


      The evaluation of the epidemiologic, toxicological, and controlled human exposure studies
published since the completion of the 2004 PM AQCD  have provided additional evidence for
PM-related health effects. Table 2-6 provides an overview of the causal determinations for all PM
size fractions and health effects. Causal determinations for PM and welfare effects, including
visibility, climate, ecological effects, and materials are included in Table 2-7. Detailed discussions of
the scientific evidence and rationale for these causal determinations are provided in the subsequent
chapters of this ISA.
December 2009                                  2-31

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Table 2-6.    Summary of PM causal determinations by exposure duration and health outcome.
Size Fraction Exposure Outcome
Cardiovascular Effects
Respiratory Effects
Central Nervous System
Mortality
PM2.5 Cardiovascular Effects
Respiratory Effects
Long-term Mortality
Reproductive and Developmental
Cancer, Mutagenicity, Genotoxicity
Cardiovascular Effects
Respiratory Effects
Central Nervous System
Mortality
PM-io-2.5 Cardiovascular Effects
Respiratory Effects
Long-term Mortality
Reproductive and Developmental
Cancer, Mutagenicity, Genotoxicity
Cardiovascular Effects
Respiratory Effects
Central Nervous System
Mortality
UFPs Cardiovascular Effects
Respiratory Effects
Long-term Mortality
Reproductive and Developmental
Cancer, Mutagenicity, Genotoxicity
Causality Determination
Causal
Likely to be causal
Inadequate
Causal
Causal
Likely to be Causal
Causal
Suggestive
Suggestive
Suggestive
Suggestive
Inadequate
Suggestive
Inadequate
Inadequate
Inadequate
Inadequate
Inadequate
Suggestive
Suggestive
Inadequate
Inadequate
Inadequate
Inadequate
Inadequate
Inadequate
Inadequate
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Table 2-7.     Summary of PM causal determinations for welfare effects
                  Welfare Effects
                   Causality Determination
Effects on Visibility
Causal
Effects on Climate
Causal
Ecological Effects
Likely to be causal
Effects on Materials
Causal
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Ostro BD; Broadwin R; Lipsett MJ. (2003). Coarse particles and daily mortality in Coachella Valley, California. Health
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Peel JL; Tolbert PE; Klein M; Metzger KB; Flanders WD; Knox T; Mulholland JA; Ryan PB; Frumkin H. (2005). Ambient
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Peters A; Dockery DW; Muller JE; Mittleman MA. (2001). Increased particulate air pollution and the triggering of
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    Chapter 3.  Source to  Human  Exposure
3.1.  Introduction

     This chapter describes basic concepts and new and established findings in atmospheric
sciences and human exposure assessment relevant to PM to establish a foundation for the health and
ecological effects discussed in subsequent chapters. Information in this chapter builds on previous
AQCDs for PM using new data and re-interpretations of extant studies as well. This includes new
knowledge of PM chemistry, the latest developments in monitoring methodologies, recent national
and local measurements and trends in PM concentrations as a function of size range and
composition, advances in receptor and chemistry-transport modeling, revised estimates of policy-
relevant background PM, and recent work on exposure assessment.
     The chapter and its associated annex material are organized as follows: Section 3.2 presents an
overview of basic information related to the size distribution  and composition of airborne particles.
Section 3.3 provides a brief description of the sources, emissions, and deposition of PM, including
discussions of possible mechanisms of secondary  PM formation from gaseous precursors and of the
atmospheric processes that deposit PM to the earth's surface.  Issues related to the measurement of
PM and its chemical components and to monitors and networks in the U.S. are covered in
Section 3.4; supplementary material on these topics is contained in Annex A, Section A. 1. Analyses
of data for ambient concentrations of PM and its components are characterized in Section 3.5, and
supplementary  information can be found in Annex A, Section A.2. Section 3.6 describes methods for
determining source contributions to ambient samples by receptor models and presents results from
recent receptor modeling studies. In addition, the  construction of chemistry-transport models
(CTMs) to determine pollutant concentrations is described in Section 3.6. Supplementary
information about receptor model methods and results is given in Annex A, Section A.3. Policy
relevant background concentrations of PM, i.e., those concentrations defined to result from natural
sources everywhere in the world together with anthropogenic sources outside of Canada, the United
States,  and Mexico, are presented in Section 3.7. Issues related to human exposure assessment
including sources of exposure and implications for epidemiologic studies are discussed in
Section 3.8. Supplementary information on exposure studies is included in Annex A, Section A.4.
Finally, the summary and conclusions from Chapter 3 are presented in Section 3.9.



3.2.  Overview of Basic Aerosol Properties

     Unlike gas-phase pollutants such as SO2, CO, H2CO and O3, which are well-defined chemical
entities, atmospheric PM varies in size, shape, and chemical composition. Atmospheric chemical and
microphysical processing of direct emissions of PM and its precursors together with mechanical
generation of particles tend to produce distinct lognormal modes (Whitby, 1978, 071181) as shown
in Figure 3-1. To the extent that information is available, discussions in this and subsequent chapters
will focus on particles in specific size ranges (i.e., PM2.5, PMi0_2.5 and PMi0). The subscripts after PM
Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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refer to the aerodynamic diameter1 (dae) in micrometers ((irn) of 50% cut points of sampling devices.
For example, EPA defines PMi0 as particles collected by a sampler with an upper 50% cut point of
10 (im dae and a specific, fairly sharp, penetration curve, as defined in the Code of Federal
Regulations (40 CFR Part 58). PM2.5 is defined in an analogous way. Ultrafme particles (UFPs),
defined here as particles with a diameter < 0.1 (im (typically based on physical size, thermal
diffusivity, or electrical mobility), will also be discussed.
      The terms "fine particles" and "coarse particles" have lost the precise meaning  as defined in
Whitby (1978, 071181). where "fine particles" refers to all particles in the nucleation, Aitken, and
accumulation modes; and "coarse particles" characterizes  all particles larger than these. UFPs
correspond loosely to the nucleation plus Aitken modes (in earlier literature, these modes were not
separated and the combination, unresolved by older instruments, was called the Aitken mode). Now,
the term "fine particles" is most often associated with the PM2.5 fraction, which includes the
nucleation, Aitken and accumulation modes and some particles from the lower-size tail of the coarse
particle mode between about 1 and 2.5 (im aerodynamic diameter. "Thoracic coarse"  is frequently
used in reference to PMi0_2.5, which does not include the low-end tail of the coarse particle mode.
With high relative humidity, larger particles in the accumulation mode could also extend into the 1 to
3 (im size range. These relationships can be seen in Figure 3-1, which shows the number distribution
for UPFs and the volume distribution (or mass distribution if particle density is constant across the
size  range) for fine and (thoracic) coarse particles. The figure is arranged this way because particle
number is most highly concentrated in the ultrafine (UF) size range but volume (or mass) is most
concentrated in the larger size ranges.
                                      Fine Particles
                                                                Coarse Particles
                                O.O1
                                            0.1           1           10
                                            Diameter (micrometers)
                                               Source:Reprinted with Permission of Cambridge University Press from Pandis (2004,1568381.

Figure 3-1.     Particle size distributions by number and volume. Dashed lines refer to values in
                individual modes and solid lines to their sum. Note that ultrafine particles are a
                subset of fine particles.
1 Aerodynamic diameter is the diameter of a unit density (1 g/cm3) sphere that has the same gravitational settling velocity as the particle of
 interest and is a useful metric for characterizing particles >~ 1 um. For sub-micron particles, forces other than gravity increase in
 importance in determining a particle's motion and air can no longer be considered a continuum. Aerodynamic diameter is frequently
 reported down to ~ 0.1 um where the assumptions used in its derivation no longer hold. A useful metric for characterizing particles <~
 0.5 um is the mobility diameter defined as the diameter of a particle having the same diffusivity or electrical mobility in air as the
 particle of interest. In the region between ~ 0.5-1.0 um, aerodynamic and mobility diameters are not necessarily the same. The question
 of how best to merge these diameters is unresolved and depends on the particle properties of interest.
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      Characterizing particle size is important because different size particles penetrate to different
regions of the human respiratory tract. Thoracic particles refer to particles that travel past the larynx
to reach the lung airways and the gas-exchange region of the lung, and respirable particles are those
that reach the gas-exchange region. The selection of PMi0 as an indicator of thoracic particles was
based in large part on dosimetry  (U.S. EPA, 1996, 079380). However, the selection of PM2.5 to
characterize respirable particles was driven mainly by considerations related to measurement
techniques available at the time rather than dosimetry. Currently, cut points other than 2.5 (im are
attainable and frequently put into use. For example, the American Conference of Governmental
Industrial Hygienists (ACGIH, 2005, 156188). the International Standards Organization, and the
European Standardization Committee have adopted a 50% cut point of 4 (im as an indicator of
respirable particles. Most commonly, however, PM2.5 is used as an indicator of respirable particles,
PMio_2.5 is used as an indicator of the thoracic component of coarse particles that is sometimes
referred to  as thoracic coarse (noting that it excludes some coarse particles below 2.5 (im and above
10 (im), and PMi0 is used as an indicator of thoracic particles.
      As can be seen from Table 3-1, particles in individual size modes are characterized by rather
distinct sources, composition, chemical properties, lifetimes in the atmosphere (T) and distances over
which they can travel. Whereas particles in the smaller size modes are formed  mainly by combustion
processes and by nucleation and condensation of gases, coarse particles are generated mainly by
mechanical activity, such as by the action of wind on either the ground or the sea surface or by
construction or by resuspension by traffic. Particles in the UF size range are either emitted directly to
the atmosphere or are formed by nucleation of gaseous constituents in the atmosphere. The
properties of fibers and engineered nano-objects and nanometer scale products (e.g., dots, hollow
spheres, rods, fibers, and tubes) are not reviewed in this chapter because these  classes of objects are
found mainly in certain occupational settings rather than in ambient air.
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Table 3-1.      Characteristics of ambient fine (ultrafine plus  accumulation-mode) and coarse  particles.
                                                       Fine
                                                                                                                     Coarse
                            Ultrafine
                                                     Accumulation
Formation
Processes
Combustion, high-temperature processes, and atmospheric reactions
                                                  Break-up of large solids/droplets
               Nucleation of atmospheric gases
               including H2S04, NH3 and some organic
Formed by      compounds
               Condensation of gases
                                     Condensation of gases
                                     Coagulation of smaller particles
                                     Reactions of gases in or on particles
                                     Evaporation of fog and cloud droplets in which gases
                                     have dissolved and reacted
                                                  Mechanical disruption (crushing, grinding,
                                                  abrasion of surfaces)
                                                  Evaporation of sprays
                                                  Suspension of dusts
                                                  Reactions of gases in or on particles
               Sulfate
               EC
Composed of    Metal compounds
               Organic compounds with very low
               saturation vapor pressure at ambient
               temperature
                                     Sulfate, nitrate, ammonium, and hydrogen ions
                                     EC
                                     Large variety of organic compounds
                                     Metals: compounds of Pb, Cd, V, Ni, Cu, Zn, Mn, Fe, etc.
                                                  Nitrates/chlorides/sulfates from
                                                  HN03/HCI/S02 reactions with coarse particles
                                                  Oxides of crustal elements (Si, Al, Ti, Fe)
                                                  CaC03, CaS04, NaCI, sea salt
                                                                                      Bacteria, pollen, mold, fungal spores, plant
                                     Particle-bound water                                and animal debris
                                     Bacteria, viruses
Solubility
               Not well characterized
                                     Largely soluble, hygroscopic, and deliquescent
                                                  Largely insoluble and nonhygroscopic
Sources
High temperature combustion
Atmospheric reactions of primary,
gaseous compounds.
Combustion of fossil and biomass fuels, and high
temperature industrial processes, smelters, refineries,
steel mills etc.
Atmospheric oxidation of N02, S02, and organic
compounds, including biogenic organic species
(e.g.,terpenes)
Resuspension of particles deposited onto
roads
Tire, brake pad, and road wear debris
Suspension from disturbed soil (e.g., farming,
mining, unpaved roads)
Construction and demolition
Fly ash from uncontrolled combustion of coal,
oil, and wood
Ocean spray
Atmospheric
half-life
Minutes to hours
                                     Days to weeks
                                                                                       Minutes to hours
Removal
Processes
Grows into accumulation mode
Diffuses to raindrops and other surfaces
Forms cloud droplets and rains out
Dry deposition
Dry deposition by fallout
Scavenging by falling rain drops
Travel distance  <1 to 10s of km
                                                    100s to 1000s of km
                                                                                      <1 to 10s of km (100s to 1,000s of km in dust
                                                                                      storms for the small size tail)
                                                 Source: Adapted with Permission of the Air & Waste Management Association from Wilson and Suh (1997, 077408)
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                                                                   Source: National Exposure Research Laboratory.

Figure 3-2.    X-ray spectra and scanning electron microscopy images of individual particles.
              These include: (1) an aluminum-silicate fly ash sphere emitted from a coal-fired
              power plant; (2) an iron oxide sphere emitted from a steel manufacturing facility;
              (3) an aluminum-silicate particle, probably of crustal origin; (4) a carbon soot
              aggregate from a diesel engine consisting of many sub-micron size carbon
              particles; (5) a sodium chloride crystal, potentially of marine origin; and (6) a
              partially collapsed pollen particle. The polycarbonate filter substrate used to
              collect the particles is visible in the background of each image and contributes to
              the carbon peak in each spectrum.

      Particles appear in a wide variety of shapes such as spheres, ellipsoids, cubes, and irregular or
fractal geometries. This is one reason why a standard metric such as aerodynamic diameter is useful
for describing the mechanical properties of the particles. The shape of particles is important for
determining the optical properties  of the particles. The directionality of sunlight scattered by certain
shapes of particles, such as plates, also depends strongly on their physical orientation while
suspended. The shape of particles also affects the surface area of the particles in contact with the
surface it is deposited on, including cell membranes.
      Images of six types of individual particles obtained using scanning electron microscope
(SEM) and their corresponding x-ray spectra showing their major  elemental composition are shown
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in Figure 3-2. The images show particles sitting on a thin polycarbonate film with pores and a 1 (im
scale bar for size reference. Air is pulled through the filter pores with a vacuum pump and the
particles are left behind on the surface. The metal dominated spherical particles (image 2) were
formed at high temperatures and were quickly cooled. Particles which are liquid such as sulfate are
also spherical. Sodium chloride (NaCl) crystals are cubic (image 5); this particular particle could be
marine sea salt due to the proximity to the ocean where the sample was collected. Other particles,
such as the carbon chain agglomerates from diesel engines have much more irregular and complex
shapes (image 4). Note that these particles were placed under vacuum resulting in volatilization of
water and other volatile components and partial collapse of the pollen grain (image 6). Changes in
composition and possibly morphology could occur during the sampling, collection and analysis of
aerosol samples.  For example, particles may be coated with semi-volatile material that evolves off
the particles under vacuum and under the electron beam. Similarly, particles in ambient air are
generally mixtures or agglomerates of particles coming from multiple sources and have a diverse
chemical make-up.



3.3.  Sources,  Emissions and Deposition  of Primary and

       Secondary PM

      PM is composed of both primary (derived directly from emissions) or secondary (derived from
atmospheric reactions involving gaseous precursors) components. Table 3-4 summarizes
anthropogenic and natural sources for the major primary and secondary aerosol constituents of fine
and coarse particles. Anthropogenic sources can be further divided into stationary and mobile
sources. Stationary sources include fuel combustion for electrical utilities,  residential space heating
and cooking; industrial processes; construction and demolition; metal, mineral, and petrochemical
processing; wood products processing; mills and elevators used in agriculture;  erosion from tilled
lands; waste disposal and recycling; and biomass  combustion. Biomass combustion encompasses
many emission activities including burning of wood for fuel, burning of vegetation to clear  land for
agriculture and construction, to dispose of agricultural and domestic waste, to control the growth of
animal or plant pests, and to manage forest resources (prescribed burning). Wildlands also burn due
to lightning strikes and arson. Mobile or transportation-related sources include direct emissions of
primary PM and  secondary PM precursors from highway vehicles and non-road sources as well as
fugitive dust from paved and unpaved roads. Also shown in Table 3-2 are sources for several
precursor gases, the oxidation of which can form secondary PM. An overview of estimates of
emissions of primary PM and precursors to secondary PM from major sources  is given in
Section 3.3.1. The transformations from gaseous precursors shown in Table 3-2 to secondary PM are
described in Section 3.3.2.
      In general, the sources of fine PM are very different from those of coarse PM.  Some of the
mass in the fine size fraction forms during combustion from material that has volatilized in
combustion chambers and then recondensed before emission to the atmosphere. Some ambient PM2.s
forms in the atmosphere from photochemical reactions involving precursor gases. Included  in this
category is the formation of new UFPs by (1) homogeneous nucleation of precursor gases and (2) the
condensation of gases on pre-existing particles. Biological material also exists in the fine fraction
including many types of microorganisms, especially viruses and bacteria and fragments  of pollens
and fungal spores. PMi0_2.5 is mainly primary in origin, as it is produced by surface abrasion or by
suspension of biological material and fragments of living things (e.g., plant and insect debris). In
addition, atmospheric reaction products condense on coarse particles. Because precursor gases
undergo mixing during transport from their sources and chemical reactions, and the oxidation of
different gases can produce the same  reaction products, it is difficult to identify individual sources of
secondary PM. Transport and transformation of precursors can occur over  distances of hundreds of
kilometers. PMi0_2.5 has a shorter lifetime in the atmosphere, so its effects tend to be more localized.
However, intercontinental transport of dust from African and Asian deserts occurs and some of this
material is in the PMi0_2.5 size range. Major intercontinental  dust events are highly episodic  but small
contributions can be present at other times (see Section 3.7).
December 2009                                  3-6

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Table 3-2.     Constituents of atmospheric particles and their major sources.
             Primary (PM <2.5 urn)
                             Primary (PM >2.5 urn)
                                          Secondary PM Precursors
                                               (PM<2.5um)
  Aerosol species      Natural     Anthropogenic
                           Natural
                         Anthropogenic
                            Natural
               Anthropogenic
    Sulfate (S042~)
Sea spray
Fossil fuel
combustion
Sea spray
Oxidation of reduced
sulfur gases emitted
by the oceans and   Oxidation of S02
wetlands and S02   emitted from fossil fuel
and H2S emitted by  combustion
volcanism and forest
fires
Nitrate (N03~)
Minerals
Ammonium (NH4*)
Organic carbon (00)
EC
Metals
Bioaerosols
Mobile source
exhaust
Fugitive dust from
paved and unpaved
Erosion and re- roads, agriculture,
entrainment forestry,
construction, and
demolition
Mobile source
exhaust
Prescribed burning,
wood burning,
\Ajwfiroc. mobile source
Wlldfires exhaust, cooking, tire
wear and industrial
processes
Mobile source
exhaust (mainly
Wildfires diesel), wood
biomass burning,
and cooking
Fossil fuel
combustion, smelting
Volcanicactivity Jg*",
processes, and
brake wear
Viruses and
bacteria
-
Erosion and re-
entrainment
-
Soil humic matter
-
Erosion, re-
entrainment, and
organic debris
Plant and insect
fragments, pollen,
fungal spores, and
bacterial
agglomerates
-
Fugitive dust, paved
and unpaved road
dust, agriculture,
forestry,
construction, and
demolition
-
Tire and asphalt
wear, paved and
unpaved road dust
Tire and asphalt
wear, paved and
unpaved road dust
-
-
Oxidation of NOX
produced by soils,
forest fires, and
lightning
-
Emissions of NH3
from wild animals,
and undisturbed soil
Oxidation of
hydrocarbons
emitted by
vegetation (terpenes,
waxes) and wild fires
-
.—
-
Oxidation of NOX
emitted from fossil fuel
combustion and in
motor vehicle exhaust
-
Emissions of NH3 from
motor vehicles, animal
husbandry, sewage,
and fertilized land
Oxidation of
hydrocarbons emitted
by motor vehicles,
prescribed burning,
wood burning, solvent
use and industrial
processes
-
-
-
Dash (—) indicates either very minor source or no known source of component.
                                                                                 Source: U.S. EPA (2004, 0569051.
      Only major sources for each constituent within each broad category shown at the top of Table
3-2 are listed. Not all sources are equal in magnitude. Chemical characterizations of primary
particulate emissions for a wide variety of natural and anthropogenic sources (as shown in Table 3-2)
were given in Chapter 5 of the 1996 PM AQCD (U.S.  EPA, 1996, 079380). Summary tables of the
composition of source emissions presented in the 1996 PM AQCD (U.S. EPA, 1996, 079380) and
updates to that information are provided in Appendix 3D to the 2004 PM AQCD (U.S. EPA, 2004,
056905).  Source composition profiles are archived by the EPA at
http://www.epa.gov/ttn/chief/software/speciate/. The profiles of source composition were based in
large measure on the results of studies that collected source signatures for use in source
apportionment studies.
December 2009
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      Natural sources of primary PM include windblown dust from undisturbed land, sea spray, and
biological material. The oxidation of a fraction of terpenes emitted by vegetation and reduced sulfur
species from anaerobic environments leads to secondary PM formation. Ammonium (NH4+) ions,
which play a major role in regulating the pH of particles, are derived from emissions of NH3 gas.
Source categories for NH3 have been divided into emissions from undisturbed soils (natural) and
emissions that are related to human activities (e.g., fertilized lands, domestic and farm animal waste).
There is ongoing debate about characterizing emissions from wildfires as either natural or
anthropogenic. Wildfires have been listed in Table 3-2 as natural in origin, but land management
practices and other human actions affect the  occurrence and scope of wildfires. For example, fire
suppression practices allow the buildup of combustible fuels and increase the susceptibility of forests
to more severe and infrequent fires from whatever cause, including lightning strikes. Similarly,
prescribed burning is listed as anthropogenic, but can be viewed as a substitute for wildfires that
would otherwise occur  eventually on the same land.


3.3.1.   Emissions of Primary PM and Precursors to Secondary PM

      U.S. national average emissions of primary PM2.5, PMi0 and gaseous precursor species (SO2,
NOX, NH3 and VOCs) from different source  categories are shown in Figure 3-3. Note that the entries
refer mainly to anthropogenic sources, with little information about natural sources. However, for
categories such as VOCs, the contribution from biogenic emissions of isoprene and terpenes can be
quite large. The entries  are continually undergoing revision and are subject to varying degrees of
uncertainty. For example, almost all of the sulfur in fuel is released as volatile components (SO2 or
SO3) during combustion. Hence, sulfur emissions can be calculated on the basis of sulfur content in
fuels to a greater accuracy than can be done for other pollutants like nitrogen oxides or primary PM.
There have been notable downward revisions to the inventories since 2002 in the emissions of dust
from roads. These have resulted in large measure from incorporation of emissions test data with
updated methods for measuring dust  emissions. Also, the spatial and temporal characterization of
wildfire emissions has improved since 2002  by integrating satellite-derived fire detection and state-
of-the-art fuels characterization and consumption models (Pouliot et al., 2008, 156883). Emission
measurements from high-temperature combustion sources are sensitive to the dilution, temperature,
and pre-treatment of dilution air (England  et al., 2007, 156420; England et al., 2007, 156421; Sheya
etal, 2008, 156977).
      To a large extent, especially with regard to the contribution of road dust to PM, refinements in
emission estimates have been guided by the use of receptor modeling. See Section 3.6.1 for a
description of receptor modeling techniques  and the 2004 PM AQCD (U.S. EPA, 2004, 056905) for
the role  of receptor models in refining emissions estimates. Note that since the estimates given in
Figure 3-3 are U.S. national averages, they may not accurately reflect the contribution of specific
local sources determining a person's  exposures to PM at any given time and location.
      As can be seen from a comparison of the total U.S. emissions (in million metric tons) shown in
Figure 3-3, estimates of total emissions of potential precursors to secondary PM formation including
SO2, NOX, NH3 and VOCs are considerably larger than those for primary PM sources. However,
translating the emissions of precursors into production rates of secondary PM or using these
emissions as a guide to estimate PM composition is highly problematic. A significant fraction of
gaseous precursors are lost before they could be converted to PM. Dry deposition and precipitation
scavenging of some of these gaseous precursors and their intermediate oxidation products occur
before they are transformed in the atmosphere, and most VOCs emitted are oxidized to carbon
dioxide (CO2) rather than to PM. Some of these precursors are also transported outside the United
States. Even if gaseous  precursors are converted to PM components, the effects of atmospheric
transformations must also be considered (discussed in  Section 3.3.2 below). As a result of these
transformations, ratios of masses of particle phase products to each other will not be the same as
those in the emissions inventories for their precursors.  For example, SO2, NOX and NH3 are
converted to secondary PM as SO42",  NO3" and NH4+. The ratios of molecular weights of PM
products (SO42~, NO3" and NH4+) to gaseous precursors (SO2, NOX and NH3) are 1.5, 1.35, and 1.07,
respectively. Estimating a conversion factor for carbon in VOCs is less straightforward. The
oxidation of VOCs leads to the formation of secondary OC in PM. As the result of atmospheric
transformations, nitrogen and oxygen are added to the carbon originally present in VOCs. Turpin and
Lim (2001, 017093) recommend adjustment factors ranging from 1.4 to 2.0 to account for the
presence of oxygen and nitrogen in organic compounds in OC in the aerosol phase.  Because of all
December 2009                                  3-8

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the above issues, the resultant mass and composition of ambient PM is quite different from what
might be inferred from examining the emissions inventories alone.
                                        Fertilizer &
                                        Lweslock
                                         0%
                                                        hdust/
                                                       CormVRes
                                                        Fuels
                                                                     Non-Road
                                                                       2%
                            PM25(5.4MMT)
                                      2%        1%
                                        PMm (19.9 MMT}
         Resdenlal
    On-R=ad  Woo
-------
3.3.2.   Formation of Secondary PM
      Precursors to secondary PM have natural and anthropogenic sources, just as primary PM has
natural and anthropogenic sources. A substantial fraction of the fine particle mass, especially during
the warmer months of the year, is secondary in nature, formed as the result of atmospheric reactions
involving both inorganic and organic gaseous precursors. The major atmospheric chemical
transformations leading to the formation of particulate nitrate (pNO3) and particulate sulfate (pSO4)
are relatively well understood; whereas those involving the formation of secondary organic aerosol
(SOA) are less well understood and are subject to much current investigation. A large number of
organic precursors are involved and many of the kinetic details still need to be determined. Also,
many of the products of the oxidation of hydrocarbons have yet to be identified. However, there has
been substantial progress made in understanding the chemistry of SOA formation in the past few
years.


3.3.2.1.   Formation of Nitrate and Sulfate

      The basic mechanism of the gas and aqueous phase oxidation of NO2 and SO2 has long been
studied and can be found in numerous texts on atmospheric chemistry, e.g., Seinfeld and Pandis
(1998, 018352). Finlayson-Pitts and Pitts (2000, 055565). Jacob (1999, 091122). and Jacobson
(2002, 090667). The reader is referred to the 2004 PM AQCD (U.S. EPA, 2004, 056905) as well as
the 2008 NOX and SOX ISAs (U.S. EPA, 2008, 157073: U.S. EPA, 2008, 157074: U.S.  EPA, 2008,
157075) where these processes are described in great detail.
3.3.2.2.   Formation of Secondary Organic Aerosol

      Some key new findings have altered perceptions of SOA formation since the 2004 PM AQCD
(see especially the reviews by Kroll and Seinfeld (2008, 155910) and Rudich et al. (2007, 156059)).
New measurement techniques for estimating the speciation and water solubility of organic aerosols
have noted the dominant contribution of oxygenated species in atmospheric particles. Recent
measurements show that the abundance of oxidized SOA exceeds that of more reduced hydrocarbon
like organic aerosol in Pittsburgh (Zhang et al., 2005, 157185) and in about 30 other cities across the
Northern Hemisphere (Zhang et al., 2007, 101119). Based on aircraft and ship-based sampling of
organic aerosols in coastal waters downwind of northeastern U.S. cities, de Gouw et al. (2008,
191757) reported that 40-70% of measured organic mass was water soluble and estimated that
approximately 37% of SOA is attributable to aromatic precursors, based on PM yields estimated for
NOx-limited conditions. However,  the remaining mass of estimated SOA (63%) was unexplained,
possibly due to oxidation of semivolatile precursors not measured by standard gas chromatography.
Aerosol yields from the oxidation of aromatic  compounds have been reported to be higher when
reactions with NOX are not dominant, suggesting that transport of less reactive compounds (e.g.,
benzene) out of source regions with high NOX levels could result in greater overall SOA yields than
previously estimated (Ng et al., 2007, 199528). Furthermore, Zhang et al. (2007, 189998) noted that
the most common mass spectrum of oxygenated OA measured in ambient air resembles mass  spectra
measured in irradiated diesel exhaust reported  by Robinson et al. (2007, 156053) and Sage et al.
(2008, 191758).
      Typical dilution sampling of combustion sources employ dilution rate, temperature, pressure,
and background aerosol concentrations that can differ substantially from ambient conditions. Lipsky
and Robinson (2006, 189891) and Robinson et al. (2007, 156053) showed that under higher dilution
conditions, the fraction of diesel engine organic emissions that volatilizes is higher than that
measured using common test methods.
      Murphy and Pandis (2009, 190095) pointed out the importance of characterizing the volatility
distribution of emissions of organic species from combustion sources for more  accurately predicting
the abundance and oxidation state of SOA in both urban and surrounding regional background
environments. They note that in urban areas, volatile emissions can be photochemically oxidized to
more non-volatile compounds which then condense, forming oxidized SOA. Braun (2009, 189997)
suggested that the weathering of diesel exhaust particles involves the desorption of semi-volatile
organic compounds followed by the decomposition and reaction  of the amorphous non-volatile
carbon. These reactions would result in the formation of a number of functional groups on the
December 2009                                 3-10

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surface of the carbon core including quinones, carbohydroxide and carboxyl groups as well as
sulfate. In general, all the above studies underscore the importance of accurately describing the
phase distribution of semivolatile organic compounds emitted by combustion sources under
atmospheric conditions, and of atmospheric photochemical reactions in modifying the composition
of emissions.
      Until a few years ago, the oxidation of terpenes and aromatic compounds were considered as
sources of SOA, and the oxidation of isoprene was not considered a source of SOA. However,
observations of 2-methyl tetrols in ambient samples from a number of different environments
suggest that small but not insignificant quantities of SOA are formed from isoprene oxidation
(Claeys et al, 2004, 058608). Laboratory studies also indicate the formation of 2-methyl tetrols from
isoprene oxidation (Edney et al., 2005, 155760; Kleindienst et al., 2006, 156650). Xia and Hopke
(2006, 179947) observed the seasonal variations for the two major diastereoisomers produced during
the oxidation of isoprene with highest concentrations occurring during summer and lowest
concentrations occurring during winter. During summer, the maximum contribution of these two
diastereoisomers to OC was 2.8%, however it is not clear if more SOA could have been produced
from isoprene oxidation.
      Kroll and Seinfeld (2008, 155910) and Rudich et al. (2007, 156059) noted that the
composition of SOA evolves from repeated cycles of volatilization and condensation of chemical
reaction products in both the particle and gas phases. Rudich et al. (2007, 156059) focused on the
oxidation of particle phase species by reaction with gas phase oxidants. Kroll and Seinfeld (2008,
155910) identified three factors that determine the SOA forming potential of organic compounds in
the atmosphere:

    1.  Oxidation reactions of gas-phase organic species. These species include alkanes, alkenes,
       aromatics, cyclic olefms, isoprene and terpenes. Note that oxidation reactions can either
       lower volatility by addition of functional groups or increase volatility by cleavage of
       carbon-carbon bonds;
   2.  Reactions in the particle, or condensed, phase that can change volatility either by oxidation
       or formation of high-molecular-weight species. These reactions can lead to the formation of
       oligomers, thereby decreasing volatility or to the formation of more volatile products; and
   3.  Ongoing reactions that result from the varied volatility of oxidation products.

      Other detailed work has focused on the formation of higher molecular weight particle-phase
oligomers (Gao et al., 2004, 156460; Kalberer et al., 2004, 156619; Tolocka et al., 2004, 087578).
the importance of cloud processing in the evolution of SOA (Blando  and Turpin, 2000,  155692;
Gelencser and Varga, 2005, 156463). and the role of acid  seeds in oligomer formation (Tolocka et
al., 2004, 087578). These results imply that ambient samples could contain mixtures of SOA from
different sources at different stages of processing, some with common reaction products making
source identification of SOA problematic. Figure 3-4 shows a schematic of processes  involved in the
formation of SOA.
December 2009                                 3-11

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          PRIMARY
            SECONDARY
        Organic
        Compounds
Gas phase

reactions
of alkanes,
aromatics, alkenes,
olefins, etc

and -OH, O3, NO2
                                 products
Aqueous

phase
reactions
of dicarbonyls,
organic acids
and -OH, -NO2, O3
                                                     Aerosol
                                                     phase
                                                     reactions
                                              products
                                                           products
                              Gas/particle partitioning
                              Nucleation, sorption, condensation/evaporation
Figure 3-4.    Primary emissions and formation of SOA through gas, cloud and condensed
              phase reactions.

      It should be noted that many of the products of terpene oxidation are oxidative in nature, and
are not merely nonreactive oxidation products. Organic peroxides represent an important class of
reactive oxygen species (ROS) that have high oxidizing potential and could cause oxidative stress in
cells on which these species deposit.  For example, Docherty (2005, 087613) found evidence for the
substantial production of organic hydroperoxides in secondary organic aerosol (SOA) resulting from
the reaction of monoterpenes with O3. Analysis of the SOA formed in their environmental chamber
indicated that the SOA was mainly organic hydroperoxides. In particular, they obtained yields of
47% and 85% of organic peroxides from the oxidation of a- and |3-pinene. The hydroperoxides then
react with aldehydes in particles to form peroxyhemiacetals, which can either rearrange to form other
compounds such as alcohols and acids or revert back to the hydroperoxides. The aldehydes are also
produced in large measure during the ozonolysis of the monoterpenes. Monoterpenes also react with
OH radicals resulting, however, in the production of more lower molecular weight products than in
their reaction with O3. Various terpenoid compounds are used in a number of household products and
can be oxidized by ozone that has infiltrated from outdoors. The oxidation of terpenoid compounds
indoors produces UFPs  as described in the 2006 O3 AQCD  (U.S. EPA, 2006,
3.3.2.3.   Formation of New Particles

      In addition to being emitted by high temperature combustion sources, new particles can form
by nucleation of atmospheric gases. New particle formation has been observed in environments
ranging from relatively unpolluted marine and continental environments to polluted urban areas
(Kulmala et al, 2004, 089159). These new, nucleation mode particles are formed from molecular
clusters. Competition between condensation of gases and clusters onto existing particles and
coagulation of clusters determines which process will dominate (McMurry et al., 2005, 191759).
Because of this competition, it is expected that particle number concentrations are dominated by
primary anthropogenic emissions in highly polluted settings  and by nucleation in remote continental
sites. However, nucleation still occurs in urban environments and can still be the major source under
certain conditions. The composition of UFPs will differ depending on the nature of their sources.
December 2009
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Nucleation is observed in the morning and extending into the afternoon, and occurs at higher rates
during summer than during winter, consistent with a photochemical process. New particle formation
events have been observed to occur over distances of several hundred kilometers in what have been
called regional nucleation events (Shi et al., 2007, 191760).
      The major gas phase nucleating species involved are sulfuric acid vapor and water vapor.
Kuang et al.  (2008, 191196) suggested that the rate of nucleation is second order with respect to
H2SO4 vapor depending on mechanism. However, other studies (e.g., Kulmala et al., 2007, 097838)
have suggested that the nucleation rate is first order with respect to H2SO4 vapor. These differences
imply that a number of mechanistic details still remain to be determined, including the interactions
with other species. However, this  disparity is small compared to classical thermodynamic binary
nucleation theory involving H2SO4 and water vapor, in which the nucleation rate is given by H2SO4
vapor to at least the 10th power (Kulmala et al., 1998, 129411). H2SO4 vapor is produced by the gas
phase oxidation of SO2 by OH radicals (U.S. EPA, 2008, 157075). Ammonia (Gaydos et al., 2005,
191762) and organic acids and bases  (amines) are also involved to some extent (Smith et al.,  2008,
199529). The formation of UFPs indoors from the oxidation of terpenoids by O3 as mentioned above
also indicates that nucleation occurs indoors as well (U.S. EPA, 2006, 088089).


3.3.3.   Mobile Source Emissions
3.3.3.1.   Emissions from Gasoline Fueled Engines

      PM emitted from gasoline fueled engines is a mix of OC, EC and small quantities of trace
metals and sulfates, with OC constituting anywhere from 26-88% of PM (Cadle et al., 1999, 007636:
Geller et al., 2006, 139644; Schauer et al., 2002, 035332). Most of the compounds in OC have yet to
be characterized. High molecular weight and large PAHs have been identified in gasoline fueled
vehicle emissions (Phuleria et al., 2006, 156867; Riddle et al., 2007, 115272). EPA exhaust emission
standards do not control PM from gasoline vehicles as stringently as diesel vehicles. PM emissions
from gasoline fueled vehicles decreased greatly as other exhaust emissions (primarily hydrocarbons
and carbon monoxide) were controlled by improvements in the catalytic converter and better control
of air-to-fuel mixture ratios for the  engine intake. When leaded gasoline was used in pre-1975 model
year vehicles, gasoline engine PM emissions were relatively large (about 300 mg/mile) and consisted
largely of lead salts from combustion of the lead additive. A current gasoline fueled vehicle emits far
lower PM, about 1-10 mg/mile. Emissions of gasoline PM increase at colder ambient temperatures
and recent rulemaking for air toxics will result in significant reduction of gasoline PM at colder
temperatures. Further details about the composition of motor vehicle emissions in the context of
source apportionment modeling can be found in Section 3.6.1.


3.3.3.2.   Emissions from Diesel  Fueled Engines

      Marti Maricq (2007, 155973) presents a conceptual model of diesel PM as a mix of
nucleation-mode SO42~ and hydrocarbons from unspent fuel and soot embedded with trace metals on
which SO42~ and hydrocarbons condense.  PM emissions from pre-2007  diesels consist largely of EC
(about 70% by mass) and OC (high molecular weight compounds derived from both diesel fuel and
lubricating oil) which is responsible for about 25% of the PM (Maricq, 2007, 155973). The EC is
non-volatile, while the organic material present exhibits temperature-dependent evaporation in
similar fashion to a mixture of C24-C32 alkanes (Sakurai et al., 2003, 113924). Sulfates constitute
about 5% of the PM. A small fraction of the diesel fuel sulfur (typically  about 1-2%) is oxidized to
sulfate. Trace elements (such as Zn and halogens, mainly from lubricating oil; and others) are also
present. Mass spectra of organic diesel particles from pre-2007 engines  appear to be largely similar
to engine lube oil with minor contributions from unburned diesel fuel.
      Effective with the 2007 model year for on-road diesel heavy-duty highway truck engines, the
new EPA PM standard (0.01 g per brake horsepower-hour [g/bhp-h]) reduced PM  emission limits by
90% from the prior standard (0.10 g/bhp-h). By comparison, uncontrolled heavy-duty diesels (pre-
1988 model years) emitted about 1-2 g/bhp-h of PM. The 2007 standard resulted in the introduction
of new emission control technology, mainly the diesel particulate filter (DPF).  Other elements of the
December 2009                                 3-13

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new control technology also include water-cooled exhaust gas recirculation (mostly for control of
NOX), a diesel oxidation catalyst (DOC) used in some vehicles and improved fuel injection systems.
      Besides the large reduction in diesel PM on a mass basis, the composition of diesel PM
changed greatly. EPA regulations required that diesel fuel for on-road vehicles contain no more than
15 ppm sulfur as of January 2007 (Lim et al., 2007, 155931). Prior to that, the limit on diesel fuel
sulfur established in 1995 for on-road vehicles was 500 ppm. The HEI-ACES  study characterizes
emissions from four engines and shows that PM emissions are about 0.001 g/bhp-h or 90% below
the level of the current (2007) emission standard (Shimpi et al., 2009, 189888). This study also
characterizes  the composition of the much lower mass of PM emitted with this new technology. PM
samples collected over a composite type test consisted of 53% sulfate, 30% OC, 13% EC and 4%
other  components, including metals. A substantial fraction of sulfur is converted to sulfate over the
diesel particulate filter resulting in the higher fractional content of sulfate emissions. However, due
to the much lower mass of PM being emitted (over a 90% reduction compared to earlier diesels) as
well as the low sulfur content of the fuel, the total mass of sulfate emitted is somewhat less than that
from earlier diesels. This work also shows that UFP number emissions are lower (about 90% lower)
and that a number of other emissions are also controlled, including PAHs, nitro-PAHs, carbonyls
(such as aldehdyes), and metals.
      Pre-2007 engines can be retrofitted with exhaust aftertreatment devices, including DPFs,
DOCs, and selective catalytic reduction (SCR) systems to reduce emissions (U.S. EPA, 2009,
189885). Hu et al. (2009, 189886) examined emissions of various metals (V, Pt) from various diesel
retrofit systems including those using V-SCR and a zeolite-based SCR with a DPF. Pakbin et al.
(2009, 189893) shows significant reductions in emissions  of various PAHs for diesels with SCR
retrofit systems for NOX control. Biswas et al. (2008, 189969) examined PM size distribution and
composition (including semi-volatiles and non-volatiles) from several advanced technology diesels
including those with SCR. They showed major reductions in PM number in most driving conditions
but did not show a reduction in PM number under cruise conditions. Biswas et al. (2009,  189880)
examined four heavy-duty diesel vehicles with various retrofits showing, in general, large reductions
in PM but, in  some cases, somewhat higher emissions (or smaller decreases than expected) for EC
andOC.
      In general, under light load conditions such as idle, diesel PM has a higher percentage of OC
emissions than at high load conditions. Under lighter loads, organic compounds  are not oxidized as
effectively as  under high loads. Under higher loads, PM contains more EC than under light loads.
Also,  newer model year diesels through the 2006 model year tend to have a higher fraction of PM
that is EC than older models.
      Emissions have been measured with the new technology engines under a number of driving
cycles besides the Federal Test Procedure. The HEI ACES study  examined emissions during a range
of test procedures. In general, the low-load test cycle resulted in lower exhaust temperatures and
higher emission than did the high-load cycles. Regeneration events also produced short-term
increases in particle emissions. However, particle emission measurements on the ACES engines were
consistently lower than those on a typical 2004 engine (Shimpi et al., 2009, 189888).
      EPA standards will result in non-road diesels also having technology like catalyzed diesel
particulate filters starting in 2012.  Similar standards have also been promulgated for locomotives
powered by diesel engines. Some work has been done with prototype SCR systems  for diesel NOX
control such as would be used for the 2010 diesel NOX standard.  This standard will  also result in
reductions for NOX similar to those seen for PM in the 2007 standard.
      There is no information on emissions from diesel engines with this new technology at
temperatures  of < 10° C. In general, the ratio of emissions under cold start conditions at low
temperatures to emissions at 24° C is significantly higher for diesel engines with new technology
compared to emissions from non-catalyst systems. Note that the engines with the newer technology
require time to allow the catalyst to reach normal operating temperatures for full emission
reductions. During the period of catalyst heating, particles will be trapped in the DPF, but volatile
components can pass through. As a result of this particle-trapping, post-2007 model year engines still
emit less than the older engines, even under cold start conditions.


3.3.4.   Deposition of PM

      Wet and dry deposition are important processes for removing PM and other pollutants from the
atmosphere on urban, regional, and global scales. The conceptual model for dry  deposition is to view
December 2009                                 3-14

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the flux deposited on a surface as the product of a concentration (mass or moles of a pollutant/m3)
times a deposition velocity (Vd) (m/s). Therefore, deposition has the units of mass per unit time per
unit area, or flux. The general approach used to estimate Vd for gases or very small particles is the
resistance-in-series method represented by Equation 3-1:
                                     Vd=l/(Ra+Rh+Rc)
                                                                                     Equation 3-1
where Ra, Rb, and Rc represent the resistance due to atmospheric turbulence, transport in the fluid
sublayer very near the elements of the surface, such as leaves or soil, and the resistance to uptake of
the surface itself, respectively. Typically, these resistances are empirically derived and can vary as a
function of wind speed, solar radiation, plant characteristics, precipitation/moisture, and soil/air
temperature. These processes are shown schematically in Figure 3-5. This approach works for a
range of substances, although it is inappropriate for species with substantial re-emissions from the
surface  or for species where deposition to the surface depends on concentrations at the surface itself.
The approach is also modified somewhat for aerosols where Rb  and Rc are replaced with a surface Vd
to account for gravitational settling.
    aerodynamic



laminar' sub-layer

       Rb
                                                    Atmospheric
                                                    Resistances
                      Canopy
                    Resistances
                    Resistance analogy for the deposition of atmospheric pollutants
                                                 Source: Courtesy of T. Pierce, USEPA/ ORD / NERL/Atmospheric Modeling Division.

Figure 3-5.     Schematic of the resistance-in-series analogy for atmospheric deposition.

      Wesley and Hicks (2000, 025018) listed several shortcomings of the then-current knowledge
of dry deposition. Among those shortcomings were difficulties in representing dry deposition over
December 2009
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varying terrain where horizontal advection plays a significant role in determining the magnitude of
Ra and difficulties in adequately determining Vd for extremely stable conditions such as those
occurring at night; see the discussion by Mahrt (1998, 048210). Under optimal conditions, when a
model is exercised over a relatively small area where dry deposition measurements have been made,
models still generally showed uncertainties on the order of ± 30% (e.g., Brook et al., 1996, 024023;
Massman et al., 1994, 043681: Padro, 1996, 052446: Wesely and Hicks, 2000, 025018). Wesley and
Hicks (2000, 025018) concluded that an important result of those comparisons was that the level of
sophistication of most dry deposition models was relatively low, and that deposition estimates,
therefore, must rely heavily on empirical data. Still larger uncertainties exist when the surface
features in the built environment are not well known or when the surface comprises a patchwork of
different surface types, as is common in the eastern U.S.


3.3.4.1.   Deposition Forms



      Wet Deposition

      Wet deposition results from the incorporation of atmospheric particles and gases into cloud
droplets and their subsequent precipitation as  rain or snow, or from the scavenging of particles and
gases by raindrops or snowflakes as they fall (Lovett, 1994, 024049). Wet deposition depends on
precipitation amount and ambient pollutant concentrations. Vegetation surface properties have little
effect on wet deposition, although leaves can retain liquid and solubilized PM.
      Landscape characteristics can affect wet deposition via orographic effects and by the closer
aerodynamic coupling to the atmosphere of tall forest canopies as compared to the shorter shrub and
herbaceous canopies. Following wet deposition, humidity and temperature conditions further affect
the extent of drying versus concentrating of solutions on foliar surfaces, which influence the rate of
metabolic uptake of surface solutes (Swietlik  and Faust, 1984, 046678). The net consequence of
these factors  on direct physical effects of wet  deposited PM on leaves is not known (U.S.  EPA, 2004,
056905).
      Rainfall introduces new wet deposition and also redistributes throughout the canopy
previously dry-deposited particles (Peters  and Eiden, 1992, 045277). The concentrations of
suspended and dissolved materials are typically highest at the onset of precipitation and decline with
duration of individual precipitation events  (Hansen et al., 1994, 046634). Sustained rainfall removes
much of the accumulation of dry-deposited particles from foliar surfaces, reducing direct foliar
effects and combining the associated chemical burden with the wet-deposited material (Lovett, 1994,
024049) for transfer to the soil. Intense rainfall may contribute substantial total particulate inputs to
the soil, but it also removes bioavailable or injurious pollutants from foliar surfaces. This  washing
effect, combined with differential foliar uptake and foliar leaching of different chemical constituents
from particles, alters the composition of the rainwater that reaches the soil and the pollutant burden
that is taken-up by plants. Once in the soil, these particle constituents may affect biogeochemical
cycles of major, minor, and trace elements. Low intensity precipitation events, in contrast, may
deposit significantly more particulate pollutants to foliar-surfaces than high intensity precipitation
events. Additionally, low-intensity events may enhance foliar uptake through the hydrating of some
previously dry-deposited particles (U.S. EPA, 2004, 056905)


      Dry Deposition

      Dry particulate deposition, especially of heavy metals, base cations, and organic contaminants,
is a complex and poorly characterized process. It appears to be controlled primarily by such
variables as atmospheric stability, macro- and micro-surface roughness, particle diameter, and
surface characteristics (Hosker  and Lindberg, 1982, 019118).  The range of particle sizes, the
diversity of canopy surfaces, and the variety of chemical constituents in airborne particles have made
it difficult to  predict and to estimate dry particulate deposition (U.S. EPA, 2004, 056905).
      Dry deposition of atmospheric particles to plant and soil surfaces affects all exposed surfaces.
Larger particles >5 um diameter are dry-deposited mainly by gravitational sedimentation  and inertial
impaction. Smaller particles, especially those with diameters between 0.2 and 2.0 um, are not readily
December 2009                                  3-16

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dry-deposited and may travel long distances in the atmosphere until their eventual deposition, most
often via precipitation. Plant parts of all types, along with exposed soil and water surfaces, receive
steady deposits of dry dusts, EC, and heterogeneous secondary particles  formed from gaseous
precursors (U.S. EPA, 1982, 017610).
      Estimates of regional particulate dry deposition infer fluxes from the product of variable and
uncertain measured or modeled parti culate concentrations in the atmosphere and even more variable
and uncertain estimates of Vd parameterized for a variety of specific surfaces (e.g., Brook et al,
1996, 024023). Even for specific sites and well-defined particles, uncertainties are large. Modeling
the dry deposition of particles to vegetation is at a relatively early stage of development, and it is not
currently possible to identify a best or most generally applicable modeling approach (U.S. EPA,
2004, 056905).


      Deposition from Clouds and Fog

      The occurrence of cloud and fog deposition tends to be geographically restricted to coastal and
high mountain areas. Several factors make it particularly  effective for the delivery of dissolved and
suspended particles to vegetation. Concentrations of particulate-derived  materials  are often many-
fold higher in cloud or fog water than in precipitation or ambient air due to orographic effects and
gas-liquid partitioning. In addition, fog and cloud water deliver particulate chemical species in a
bioavailable-hydrated form to foliar surfaces. This enhances deposition by sedimentation and
impaction of submicron aerosol particles that exhibit low Vd before fog droplet formation (Fowler  et
al., 1989, 002515). Deposition to vegetation in fog droplets is proportional to wind speed, droplet
size, concentration, and fog density.  In some areas, typically along foggy coastlines or at high
elevations, this deposition represents a substantial fraction of total deposition to foliar surfaces
(Fowler et al., 1991, 046630).


3.3.4.2.   Methods for Estimating Dry Deposition

      Methods for estimating dry deposition of particles  are more restricted than for gaseous species
and fall into two major categories: surface analysis methods, which include  all types of estimates of
contaminant accumulation on surfaces of interest, and atmospheric deposition rate methods, which
use measurements of contaminant concentrations in the atmosphere and  descriptions of surrounding
surface elements to estimate deposition rates (Davidson  and Wu, 1990, 036799). Surface extraction
or washing methods characterize the accumulation of particles on natural surfaces of interest  or on
experimental surrogate surfaces. These techniques rely on methods designed specifically to remove
only surface-deposited material. Total surface rinsate may be equated to  accumulated deposition or
to the difference in concentrations in rinsate between exposed and control (sheltered) surfaces and
may  be used to refine estimates of deposition. Foliar extraction techniques may underestimate
deposition to leaves because of uptake and translocation processes that remove pollutants from the
leaf surface (Garten and Hanson, 1990, 036803: Taylor et al., 1988, 019289). Foliar extraction
methods  also cannot distinguish gas from particle-phase sources (Bytnerowicz et al., 1987, 036493;
Dasch, 1987, 036496; Kelly, 1988, 037379; Lindberg and Lovett, 1985, 036530; Van Aalst, 1982,
036481).
      The National Dry Deposition Network was established in 1986 to  document the magnitude,
spatial variability, and trends in dry deposition across the United States.  Currently, the network
operates  as a component of the CASTNet (Clarke et al., 1997, 025022). A significant limitation on
current capacity to estimate regional effects of NOX and SOX deposition  is inadequate knowledge of
the mechanisms and factors governing particle dry deposition to diverse  surfaces (U.S. EPA, 2004,
056905).
      Collection and analysis of stem flow and throughfall  can  also provide useful estimates of
particulate deposition when compared to directly sampled precipitation.  The method is most precise
for particle deposition when gaseous deposition is a small component of the total dry deposition and
when leaching or uptake of compounds of interest out of or into the foliage is not a significant
fraction of the deposition because these lead to positive and negative artifacts in the calculated totals.
      Foliar washing, whether using precipitation or experimental lavage, is one of the best available
methods  to determine dry deposition to vegetated ecosystems. Major limitations include the site
specificity of the measurements and the restriction to elements that are largely conserved within the
December 2009                                  3-17

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vegetative system. Surrogate surfaces have not been found that can adequately replicate essential
features of natural surfaces, and therefore do not produce reliable estimates of particle deposition to
the landscape.
      Micrometeorological methods employ eddy covariance, eddy accumulation, or flux gradient
protocols for quantifying dry deposition. These techniques require measurements of particulate
concentrations and of atmospheric transport processes. They are currently well developed for ideal
conditions of flat, homogeneous, and extensive landscapes and for chemical species for which
accurate and rapid sensors are available. Additional studies are needed to extend these techniques to
more complex terrain and more chemical species.
      The eddy covariance technique measures vertical fluxes of gases and fine particles from
calculations of the mean covariance between the vertical component of wind velocity and pollutant
concentration (Wesely et al., 1982,  036564) using sensors acquiring concentration data at 5-20 Hz.
For the flux gradient or profile techniques, vertical fluxes are calculated from a concentration
difference and an eddy exchange coefficient determined at discrete heights (Erisman et al., 1988,
036510; Huebert et al., 1988, 036569). Most measurements of eddy transport of PM have used
chemical sensors (rather than mass  or particle  counting) to focus on specific PM components. These
techniques have not been well developed for generalized particles and may be less suitable for coarse
particles that are transported efficiently in high frequency eddies (Gallagher et al., 1988, 046631).


3.3.4.3.   Factors Affecting Dry Deposition Rates and  Totals

      In the size range of-0.1-1.0  um where Vd is relatively independent of particle diameter as
shown in Figure 3-6, parti culate deposition is controlled by roughness of the surface and by the
stability and turbulence of the atmospheric surface layer. Impaction and interception dominate over
diffusion as dry deposition processes, and the Vd is considerably lower than for particles that are
either smaller than ~0.1 um or larger than ~1.0 um.
      Deposition of particles between  1 and 10 um diameter is strongly dependent on particle size as
shown in Figure 3-6. Larger particles within this size range are collected more efficiently at typical
wind speeds than are smaller particles (Clough, 1975, 070850). suggesting the importance of
impaction. Impaction is related to wind speed, the square of the particle diameter, and the inverse of
the deposition surface cross-section. As a depositing particle's trajectory deviates from the
streamlines of the air in which it is  suspended, increasing either wind speed or the ratio of particle
size to the deposition surface cross-section increases the probability of collision.
      Empirical estimates of Vd for fine particles under wind tunnel and field conditions are often
several-fold greater than predicted by theory (Unsworth and Wilshaw,  1989, 046682). A large
number of transport phenomena, including streamlining of foliar obstacles, turbulence structure near
surfaces, and various phoretic transport mechanisms are not well characterized (U.S. EPA, 2004,
056905). The discrepancy between estimated and predicted values of Vd may  reflect model
limitations  or experimental limitations in the specification of the effective size and number of
deposition obstacles. Previous reviews (e.g., U.S. EPA, 1996, 079380: U.S. EPA, 2004,  056905)
suggest the following generalizations: (1) particles >10 urn exhibit  variable Vd between 0.5 and
1.1 cm/s depending on friction velocities, whereas a minimum particle Vd of 0.03 cm/s exists for
particles in the size range 0.1 to 1.0 um; (2) the Vd of particles is approximately a linear function of
friction velocity; and (3) deposition of particles from the atmosphere to a forest canopy is from 2 to
16 times greater than deposition in  adjacent  open terrain like grasslands or other low vegetation.
December 2009                                  3-18

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                   O
                   o
                   O
                   8
                   o.
                   CD
                   Q
1,000


 100


  10


   1 —


  0.1 —


 0,01 —


0.001
                        0.000
                                       ' Stokes Law
                                       » Bro^nian Diffusion
                                       • Peter* and Eiden
                                       • Little and Mfen (1677)
                            0.001
                        I
                       0.1
                                                        T
0.01      0.1       1       10
     Particle Diameter (Mm)
100
                                                                           Source: U.S. EPA (2004, 0569051.
Figure 3-6.    The relationship between particle diameter and Vd for particles. Values measured
              in wind tunnels by Little and Wiffen (1977, 070869) over short grass with wind
              speed of 2.5 mi/s closely approximate the theoretical distribution determined by
              Peters and Eiden (1992, 045277) for a tall  spruce forest. These distributions
              reflect the interaction of Brownian diffusivity (descending dashed line), which
              decreases with particle size and sedimentation velocity (ascending dotted line
              derived from Stokes Law), which increases with particle size. Intermediate-sized
              particles (0.1-1.0 urn) are influenced strongly by both particle size and
              sedimentation velocity, and deposition is relatively independent of size.
      Leaf Surface Effects on Vd

      The chemical composition of a particle is not usually considered to be a primary determinant
of its Vd. Rather, the plant leaf surface has an important influence on the Vd of particles, and
therefore on the flux of dry deposition to the terrestrial environment. Relevant leaf surface properties
include stickiness, microscale roughness, and cross-sectional area. These properties  affect the
probability of impaction and particle bounce. The efficiency of deposition to vegetation also varies
with leaf shape. Particles impact more frequently on the adaxial (upper) surface than on the abaxial
(lower) surface. Most particles accumulate in the midvein, central portion  of leaves. The greatest
particle loading on dicotyledonous leaves is frequently on the adaxial surface at the  base of the
blade, just above the petiole junction. Precipitation washing probably plays an important role in this
distribution pattern (U.S. EPA, 2004, 056905).
      Lead particles have been shown to accumulate to a greater extent on older as compared with
younger needles and twigs of white pine, suggesting that wind and rain may be insufficient to fully
wash the foliage. Fungal mycelia (derived from windborne spores) were frequently observed in
intimate contact with other particles on leaves,  which may reflect minimal re-entrainment of the
spore due to shelter by the particles, mycelia development near sources of soluble nutrients provided
by the particles, or simply co-deposition (Smith and Staskawicz,  1977, 046675).
      Leaves with complex shapes tend to collect more particles than do those with shapes that are
more regular. For example, conifer needles are  more efficient than broad leaves in collecting
particles by impaction as a result of the small cross-section of the needles relative to the larger leaf
laminae of broadleaves allowing for greater penetration of wind into conifer canopies than broadleaf
ones (U.S. EPA, 2004, 056905).
December 2009
                      3-19

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      Canopy Surface Effects on Vd

      Surface roughness increases particulate deposition, and Vd is usually greater for a forest than
for a nonforested area and greater for a field than for a water surface. Different size particles have
different transport properties and Vd. The upwind leading edges of forests, hedgerows, and
individual plants are primary sites of coarse particle deposition. Impaction at high wind speed and
the sedimentation that follows the reduction in wind speed and carrying capacity of the air in these
areas lead to preferential deposition of larger particles (U.S. EPA, 2004, 056905).
      Air movement is slowed in proximity to vegetated surfaces. Canopies of uneven age or with a
diversity of species are typically aerodynamically rougher and receive larger inputs of dry-deposited
pollutants than do smooth, low, or monoculture vegetation (Garner et al., 1989, 042085; U.S. EPA,
2004, 056905). Canopies on slopes facing the prevailing winds receive larger inputs of pollutants
than more sheltered, interior canopy  regions.
      All foliar surfaces within a forest canopy are not equally exposed to particle deposition. Upper
canopy foliage tends to  receive maximum exposure to coarse and fine particles, but foliage within
the canopy tends to receive primarily fine aerosol exposures. The dry deposition of fine-mode
particles and unreactive gases tends to be more evenly  distributed throughout the canopy.
      Both uptake and release of PM constituents can occur within the canopy. The leaf surface is a
region of leaching and uptake.  Exchange also occurs with epiphytic organisms and bark and through
solubilization of previously dry-deposited PM. Vegetation emits a variety of particles and particulate
precursor materials.
3.4.  Monitoring  of PM
3.4.1.   Ambient Measurement Techniques
3.4.1.1.   PMMass

      Federal reference methods (FRMs) and federal equivelance methods (FEMs) for PM were
discussed in detail in the 2004 PM AQCD (U.S. EPA, 2004, 056905). Issues discussed there include
the definition or description of FRMs and FEMs for PM2.5 and PMi0, and measurement methods for
PM^.2.5. Also included are detailed descriptions of the WINS impactor, virtual and cascade
multistage impactors for PMi0_2.5 measurement, high-volume and low-volume PMi0 samplers, and
real-time or continuous methods for PM2.5 and PMi0 including:
       •   Tapered Element Oscillating Microbalance (TEOM) operated at various temperatures;

       •   Sample Equilibration System (SES)-TEOM;

       •   Differential TEOM;

       •   (3-Gauge Techniques (BGT);

       •   Piezoelectric Microbalance;

       •   Real-Time Total Ambient Mass Sampler (RAMS);

       •   Continuous Ambient Mass Monitor (CAMM);

       •   Continuous Coarse Particle Monitor (CCPM);

       •   Micro-orifice Uniform Deposit Impactor (MOUDI);
December 2009                                 3-20

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       •  Multichannel diffusion denuder sampling system (BOSS); and

       •  Light scattering photometric instruments.

      In this section, FRMs and FEMs for PM2.5, PMi0_2.5, and PMi0 will be revisited and evaluated
based on the cumulative understanding of these methods with a focus on evaluations performed
following the 2004 PM AQCD (U.S. EPA, 2004, 056905). followed by the discussion of new
techniques under development or evaluation.


      Federal Reference Method and  Federal Equivalent Method

      FRM and FEM PM samplers are designed to measure the mass concentrations of ambient
particulate matter. The FRMs for measuring PM2 5, PMi0_2.5, and PMi0 are specified in CFR 40 Part
50, Appendices L, O and J, respectively. The FRM for PM2.5 is a hybrid-based method that specifies
certain aspects of the method (e.g., component dimensions and tolerances, sample handling and
analysis) by design specifications and other aspects (e.g., flow control) by performance
specifications (U.S. EPA, 2004, 056905).  The PM10 FRM is performance-based; particles are
inertially separated with a penetration efficiency of 50% at 10 ± 0.5 um aerodynamic diameter. The
required collection efficiency as a function of particle size larger and smaller than 10 um
aerodynamic diameter is explicitly specified by a penetration curve in the CFR. Particles larger than
10 um in aerodynamic diameter are collected on the filter with diminishing collection efficiency as
particle size increases. Likewise, particles smaller than 10 um in aerodynamic diameter are
collected on the filter with increasing collection efficiency as particle size decreases. The FRM for
PMio_2.5 concentration is computed as the  numeric difference between concurrent and co-located
PMio and PM2.5 concentrations obtained from low-volume FRM samplers of the same make and
model. It should be noted that while the FRM for PM2 5 and PMi0_2.5 reports data under local
conditions, the FRM for PMi0 reports data corrected to standard temperature (298 K) and pressure
(101.3 kPa)(STP).
      A very sharp cut cyclone (VSCC) was approved in 2004 as a Class II PM2.5 FEM method
(Kenny et al., 2004, 155895). The VSCC  provides superior performance over long sampling periods
under heavy loading and was also incorporated as an optional second-stage separator for the PM2 5
FRM (71 FR 61214, October 17, 2006). In 2006, EPA finalized new performance criteria (40 CFR
Part 53) for the approval of FEMs as Class II equivalent methods when based on integrated filter
sampling and as Class III equivalent methods when based on continuous technologies that can
provide at least hourly data reporting. The performance criteria include evaluating additive bias
(intercept) and multiplicative bias (slope)  as well as correlation with co-located candidate and FRM
methods at field studies covering multiple seasons and sampling locations. As a result of these new
performance criteria, EPA has recently approved two filter-based PM2.5 and two filter-based PMi0_2.s
Class II FEMs based on the virtual impactor techniques (dichotomous sampler), and five PM2 5 and
one PMio_2.5 Class III  continuous FEMs based on BGT or TEOM techniques. The most recent list of
FRMs  and FEMs can be found in Annex A, Table A-2 and on the following EPA web site:
http://www.epa.gov/ttn/amtic/files/ambient/criteria/reference-equivalent-methods-list.pdf
      Evaluations of FRMs and FEMs were conducted both in supersite studies and in other research
studies (Ayers, 2004, 097440: Brown et al., 2006, 097665: Butler et al., 2003, 156313: Cabada et al.,
2004, 148859: Chang  and Tsai, 2003, 155718: Charron et al., 2004, 053849: Grover et al., 2005,
090044: Hains et al., 2007, 091039: Hering et al., 2004,  155837: Jaques et al., 2004, 155878: Krieger
et al., 2007, 129657: Lee et al., 2005, 155925: Lee et al., 2005, 128139: Price et al., 2003, 098082:
Rees et al., 2004, 097164: Russell et al., 2004, 082453: Salminen and Karlsson, 2003, 156070:
Schwab et al., 2004, 098450: Schwab et al., 2006, 098449: Solomon et al., 2003, 156994: Tsai et al.,
2006, 098312: Vega et al., 2003, 105974:  Wilson et al., 2006, 091142: Yi et al., 2004, 156169: Zhu et
al., 2007, 098367) (see Annex A, Tables A-3, A-5 and A-ll). In general, the co-located FRMs
showed very good precision with coefficient of variation (CV) <5%. For different co-located FRMs,
the regression slope of one sampler on another is commonly  close to unity with R2 >0.95. The PM25
and PMio concentrations measured by dichotomous samplers were within 10% of the FRM methods,
and the differences can be attributed to the sampling artifacts of semi-volatile components; see
Section 3.4.1.2 for details. The precision of various TEOMs ranges from 10-30%. The concentration
measured by the TEOM operated at 50°C  was consistently lower than those measured by the TEOM
operated at 30°C. The differences between these monitors were also found to be a function of season
December 2009                                  3-21

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and location. BGTs were highly correlated with FRMs but BGT mass could be higher than the FRM
mass (30% higher at the Fresno supersite) (Chow et al., 2008, 156355). Additionally, a number of
techniques have been developed to reduce positive and negative sampling artifacts. These are
described in the ISA for NOX and SOX - Ecological Criteria (U.S. EPA, 2008, 157074).
      Several papers (Buser et al., 2007, 156310: Buser et al., 2007, 156311: Buser et al., 2007,
156312) published since the 2004 PM AQCD (U.S. EPA, 2004, 056905) claim that the EPA FRM
samplers for PM10 "oversample certain agricultural and other source emissions." These claims are
based on the erroneous assumption that the "true" PMi0 concentration is what would be given by a
PMio sampler that excluded all particles greater than 10 (im aerodynamic diameter and included all
particles less than 10 (im aerodynamic diameter. The legal definitions for PM2.5 and PMi0, as defined
in the CFR (40 CFR Part 58), include both a 50% cut-point and a penetration curve. For PMi0, the
50% cut-point of 10 ± 0.5 (im aerodynamic diameter means that 50% of particles with aerodynamic
diameter of 10 ± 0.5 (im are removed by the inlet and 50% pass through the inlet where they are
collected on the filter. The penetration curve specifies, as a function of particle size, the fraction of
particles larger than 10 (im that pass through the inlet and the fraction of particles less than 10 (im
that are intercepted by the inlet. No effort was made in the development of the FRM to have the
PMio sampler collect all particles  less than 10 (im and no particles greater than 10 (im since the
sampler was designed to collect a fraction of atmospheric particles similar to the "inhalable" or
thoracic fraction, i.e., those particles that would pass through the nose and throat and reach the lungs
(Miller et al.,  1979, 070577: U.S.  EPA, 2004, 056905). Thus, the FRM PM10 sampler correctly and
intentionally collects particles greater than 10 (im.
      For PM2.5 and PMio, it has long been known that FRMs are subject to sampling artifacts
including particle bounce on heavily-loaded impaction substrates and the loss of semi-volatile
components of PM (e.g., NH4NO3, and some organics). Although there are no standard reference
materials that provide a test of accuracy of the sampling method for airborne PM mass, in
comparison with other sampling techniques that can measure both semi-volatile and nonvolatile PM,
FRMs reported PM2.5 or PMio mass concentrations biased low by as much as 10-30% (Chow et al.,
2008, 156355). The bias of the FRMs depends on the composition of ambient PM and the sampling
conditions (e.g., ambient temperature and relative humidity), which vary from day to day and from
season to season. Another limitation of the current FRM sampling protocol is that filter samples are
typically collected every 3 or 6 days (only -150 of the 900+ PM2.5 FRMs operating in 2007 were
scheduled  to sample every day). Under this operating condition, the concentration-response
relationship in air pollution health studies (especially in time-series  studies) cannot be fully
evaluated in terms of lag structures and distributed lags between ambient concentration and health
outcome (Lippmann, 2009, 190083: Solomon  and Hopke, 2008, 156997).


      Development and Evaluation of New Techniques

      Several new innovations have recently emerged to measure both fine and coarse PM fractions
in the ambient air. These techniques include the Filter Dynamics Measurement System-TEOM
(FDMS-TEOM) (Grover et al., 2006, 138080) for real-time measurement of PM2.5 or PMi0 and
several new methods for measurement of PM 10.2.5. In addition, several new techniques exist for
measuring UFPs (discussed later in Section 3.4.1.4) and for estimating PM mass concentration
indirectly using particle size (discussed later in Section 3.4.1.5).

      Real-time Measurement of PM2.5 or PM10 using the FDMS-TEOM

      The FDMS-TEOM incorporates self-referencing capability to the traditional TEOM by
alternating measurement of ambient air and chilled clean air  (particles and semivolatile gases are
removed by filtration at 4°C after which the clean air is reheated to 30°C) in 6-min intervals. As
clean air flows over the sample filter, the semivolatile PM on the sample filter is evaporated. Thus,
the instrument provides  direct measurements of the nonvolatile particle mass and incorporates an
adjustment for the semivolatile NH4NO3 and organic material. In a comparison between the TEOM,
FDMS-TEOM, and FRM mass, the PM2.5 concentration measured by the TEOM operated at 50°C
was consistently lower than those measured by the TEOM operated at 30°C. The TEOM  operated at
30°C provided concentrations 50% lower than the FDMS-TEOM, and the FDMS-TEOM provided
concentrations 10-30% higher than the FRM mass (Chow et  al., 2008, 156355: Schwab et al., 2006,
098449).
December 2009                                  3-22

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      Techniques for Measurement ofPM10.2.s

      Methods developed to measure PM10_2.5 are based on three measurement techniques: (1) virtual
impactors using low-volume, high-volume, and real-time techniques; (2) cascade impactors; and
(3) passive samplers.
      A low-volume dichotomous sampler (operated at 16.7 L/min), based on virtual impaction, was
described in the 2004 PM AQCD (U.S. EPA, 2004, 056905). Since then, a high-volume dichotomous
sampler was developed to operate at 1,000 L/min (Sardar et al, 2006,  156071). The sampler was
evaluated in the field by comparison with a MOUDI sampler, and the measured PM10_2.5 mass
concentrations were within 10%. The high-volume dichotomous sampler provides sufficient mass
collection for comprehensive standard chemical analyses over short sampling intervals. Using the
virtual impactor technique in conjunction with a TEOM or BGT as the detector, continuous PMio_2.s
measurement techniques were developed (Misra et al., 2001, 018998; Misra et al., 2003, 195001;
Solomon and Sioutas, 2008, 190139). The TEOM method was highly correlated with the PMio_2.5
FRM, but mass concentrations measured by the TEOM were 20-30% lower (Solomon  and Sioutas,
2008, 190139). The BGT method also agreed well with the PM10_25 FRM (slopes = 0.88-1.17, and
R2>0.95) (Solomon and Sioutas, 2008, 190139).
      Case et al. (2008, 155149) evaluated a cascade PM sampler designed to collect PMi0_2.5 on a
foam impactor. Particle bouncing on impactors has long been a concern for PM collection. Porous
foam was used to serve as the impactor substrate to reduce particle bounce and to collect relatively
large amounts of particles (Demokritou et al., 2004, 186901; Demokritou et al., 2004, 190115;
Huang et al., 2005, 186991; Kuo et al., 2005, 186997). The sampler was operated at 5 L/min, and it
agreed with a low-volume dichotomous sampler within ±20%. The precision of the sampler was
20% as determined by the CV.
      An inexpensive passive sampler for PMi0_25 was also developed (Leith et al., 2007, 098241;
Ott et al., 2008, 195004; Wagner and Leith, 2001, 190153; Wagner and Leith, 2001, 190154).  The
passive sampler collects particles by gravity, diffusion, and convective diffusion onto a glass
coverslip, and then an image analysis is conducted on the collected particles to estimate mass flux as
a function of aerodynamic diameter. Leith et al. (2007, 098241) conducted a field evaluation of the
passive sampler, and the difference between a FRM and the co-located passive sampler was within
la of concentrations measured with PMi0_2.5 FRM samplers. Ott et al. (2008,  119394) reported the
precision of the sampler was 11.6% (CV), and the detection limit was 2.3  |j,g/m3 for a 5-day sample.


3.4.1.2.  PM Speciation

      The following sections describe recent developments regarding measurement techniques to
ascertain quantities of particle-bound water, cations and anions, elemental composition, carbon, and
organic species.


      Particle-Bound Water

      Particle-bound water is an important component of ambient PM (U.S. EPA, 2004, 056905).
Recently, a differential method was developed to measure particle-bound  water (Santarpia et al.,
2004, 156944; Stanier et al., 2004, 095955). The dry ambient aerosol size spectrometer (DAASS)
can measure particle-bound water in the particle size range from 3 nm-10 (im (Stanier et al., 2004,
095955). by alternatively measuring ambient PM size distribution at low relative humidity (RH) and
ambient RH. A comparison of the two size distributions provides information on the water
absorption and change in particle size due to RH. Khlystov et al. (2005, 156635) reported that the
particle-bound water, measured by DAASS, was underestimated for particles <200 nm and
overestimated for particles >200 nm compared with thermodynamic models.  The loss of
semi-volatile  components during measurement may bias the particle-bound water measurement
results. Methods and analytical specifications for particle-bound water are listed in Annex A,
Table A-12.
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      Cations and Anions

      The measurement of cations and anions including SO42~, NO3~, NH4+, Cl", Na+, and K+ still
relies primarily on filter-based collection, water based extraction and ion chromatography (1C) based
chemical speciation and quantification. In addition, denuders are frequently used in the sampling
system to adjust for sampling artifacts. These methods have been reviewed in the 2004 PM AQCD
(U.S. EPA, 2004, 056905). Filter-denuder based integrated sampling methods for SO42~, NO3~, and
NH4+ have been detailed in the 2008 SOX - Health ISA (U.S. EPA, 2008, 157075) and the 2008 NOX
and SOX - Ecological ISA (U.S. EPA, 2008, 1570741
      Recent developments in multiple ion measurements have focused on the coupling of 1C and a
sample dissolution system, represented by the Particle into Liquid  Sampler-Ion Chromatography
(PILS-IC) and the Ambient Ion Monitor (AIM) (Orsini et al., 2003, 156008; Weber et al., 2001,
024640). When ambient PM passes through the PILS-IC system, water droplets are generated by
mixing ambient PM with saturated water vapor and collected by impaction. The resulting liquid
stream is then introduced into the 1C system for ion speciation and quantification. Hourly
concentrations of multiple ions can be obtained with the system, with a CV of 10%. For the AIM
system, a parallel plate denuder is used to remove the interfering gases, and then particles enter a
super-saturation chamber to form droplets. The collected droplets are then introduced into the 1C for
analysis. The AIM system can provide hourly concentrations for multiple ions. The particle mass
spectrometer is another advance in multiple PM component measurements, but most of these types
of measurements are semi-quantitative and will be detailed later in Section 3.4.1.3. Note that
measurement and analytical specifications for ions other than SO42~ and NO3~ are listed in Annex A,
Table A-9.

      Sulfate

      Methods used for continuous (sampling interval of minutes) measurements of SO42~ include
Aerosol Mass Spectrometry (AMS) (Drewnick et al., 2003, 099160; Hogrefe et al., 2004, 156560).
PILS-IC (Weber et  al., 2001, 024640). flash volatilization techniques (Bae, 2007, 155669;
Stolzenburg  and Hering, 2000, 013289) and the Harvard School of Public Health (HSPH) tube
furnace to convert SO4 ~ to SO2 for detection by a SO2 analyzer (Allen et al., 2001,  156205). These
methods are  described in detail by Drewnick et al. (2003, 099160). along with an inter-sampler
comparison that found overall agreement within 2.9% for all continuous instruments with R2 of 0.87
or better. When compared with filter samples, Drewnick et al. (2003, 099160) showed differences
were less than 25% for the AMS, PILS, flash vaporization, and HSPH continuous SO42~ monitors.
The Thermo 5020 particulate sulfate analyzer (based on the HSPH technique) compared within 80%
of 24-h filter-based measurement at a rural site in New York (Schwab et al., 2006, 098449). Annex
A, Tables A-8 and A-14, list detailed methods and analytical specifications for sampling SO42~.

      Nitrate

      In addition to the nylon filter-based method and the new developments mentioned for SO42~,
methods based on flash volatilization-chemiluminescence analysis and catalytic
conversion-chemiluminescence analysis have also been developed for continuous NO3~
measurement (averaging time 30 s-10 min). For the flash volatilization system (Fine et al., 2003,
155775; Stolzenburg  and Hering, 2000, 013289; Stolzenburg et al., 2003,  156102). particles are
collected by  a humidified impaction process and analyzed in place by flash vaporization and
chemiluminescent detection of the evolved NOX. For the catalytic conversion-chemiluminescence
analysis system (Weber et al., 2003, 157129). NO3~ was measured by conversion of particle NO3~
into NO, and then detected with the chemiluminescence method. Field and lab comparisons were
conducted to compare the different instruments mentioned above. Although the R&P 8400N ambient
particulate NO3~ monitor, which is based on the Stolzenburg flash vaporization technique, could
provide 10-min resolution data and showed excellent precision (with a CV <10%) (Harrison et al.,
2004, 136787; Hogrefe et al., 2004, 156560; Long and McClenny, 2006, 098214; Rattigan et al.,
2006, 115897). it consistently reported NO3~ concentrations -30% lower than the denuder-filter
systems in both the Baltimore supersite and the multiyear field study in New York (Harrison et al.,
2004, 136787; Hogrefe et al., 2004, 156560; Rattigan et al., 2006,  115897). In the New York
measurement campaign, an AMS was also co-located with other instruments to obtain the real-time
NO3~ information. AMS did not always agree well with the denuder-filter system for reasons not
December 2009                                  3-24

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entirely apparent. However, Bae et al. (2007, 156244) reported that some organic compounds can
also produce signals at mass-to-charge ratio m/z = 30, which is one of the characteristic m/z for
NO3~. Therefore, the disagreement between the AMS and the filter-based method could be a result of
the interference of organic compounds using the AMS. Annex A, Tables A-7 and A-13, list methods
and analytical specifications for sampling NO3~.

      Ammonium

      Several continuous and semi-continuous instruments can be used to monitor ambient
ammonium concentrations (Al-Horr et al., 2003, 153951; Bae, 2007, 155669) including many listed
above for SO42~ and NO3~. Bae et al. (2007, 155669) conducted an inter-comparison of three
semi-continuous instruments during the New York multiyear air sampling campaign: a PILS-IC, an
AMS, and a wet scrubbing-long path absorption photometer. Bae et al. (2007, 155669) reported the
inter-sampler coefficients of determination (R2) between these instruments were above 0.75, and the
slopes (with zero intercept) were between 0.71 and 1.04. Annex A, Table A-9 describes measurement
of ions other than NO3~ and SO42~, including NH4+.


      Elemental Composition

      Techniques for measuring the elemental composition of PM samples were reviewed in the
2004 PM AQCD (U.S. EPA, 2004, 056905). These methods include:

       •   Energy dispersive X-ray fluorescence (ED-XRF);

       •   Synchrotron X-ray fluorescence (SXRF);

       •   Particle-induced X-ray emission (PIXE);

       •   Particle elastic scattering analysis (PESA);

       •   Total reflection X-ray fluorescence (TR-XRF);

       •   Instrumental neutron activation analysis (INAA);

       •   Atomic absorption spectrophotometry (AAS);

       •   Inductively-coupled plasma-atomic emission spectroscopy (ICP-AES);

       •   Inductively-coupled plasma-mass spectrometry (ICP-MS); and

       •   Scanning electron microscopy (SEM).

      Recent development in this  area focused on the semi-continuous measurement methods, in
which elements were analyzed in the lab using the methods mentioned above on time-resolved
and/or size resolved samples (Kidwell and Ondov, 2004, 155898). The concentrated slurry/graphite
furnace atomic absorption spectrometry (GFAAS) method collects ambient PM as a slurry using
impactors, and then the collected PM  is analyzed by AAS in the lab. Laser induced breakdown
spectroscopy (LIBS) was used to measure seven metals at the Pittsburgh supersite. LIBS
concentrates ambient PM using a virtual impactor into a sample cell, and then a Nd: YAG
laser-spectrometer is used to identify and quantify different elements. A full listing of measurement
techniques and analytical specifications for trace elements is provided in Annex A, Table A-6.


      Elemental and Organic Carbon

      The large variety of aspects of carbon analyses were reviewed in the 2004 PM AQCD
(U.S. EPA, 2004, 056905). Measurement and analytical specifications for carbon measurements are
listed in Annex A, Tables A-10 and A-15. Aspects of the measurements include sampling artifacts
December 2009                                 3-25

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associated with the integrated filter-based OC and EC sampling methods, the IMPROVE vs. CSN
thermal optical protocols (i.e., different thermal optical methods) and optical techniques to measure
light-absorption or BC. One significant change taking place in the CSN is that the method for carbon
measurements is being changed from the CSN method to a method designed to be consistent with
the IMPROVE carbon analysis protocol. This is a phased process that began in May of 2007 with the
conversion of 56 stations. Phase 2 of the carbon sampler conversion occurred in April of 2009 with
another 62 stations. The balance of the CSN is scheduled to be  converted to IMPROVE-like
sampling and IMPROVE analysis in late 2009 (Henderson, 2005, 156537). The CSN network was
implemented to support the PM2.5 NAAQS and provides data for PM2.5 mass, SO42~, NO3~, NH4+, Na,
K, EC, OC, and select trace elements (Al through Pb) at many sites across the U.S.  This conversion
will increase consistency between these two networks. Also, since the release of the 2004 PM AQCD
(U.S. EPA, 2004, 056905). more studies have been conducted to extend the understanding of
sampling artifact issues (Chow et al., 2008, 156355; Watson et  al., 2005, 157125). evaluate different
thermal and optical procedures (Chen et al., 2004, 199501; Chow et al., 2004, 156347; Chow et al.,
2005, 155728; Chow et al., 2007, 156354; Conny et al., 2003, 145948; Han et al., 2007, 155823;
Subramanian et al., 2004, 081203; Watson et al., 2005, 157125). develop reference  materials
(Klouda et al., 2005, 130382; Lee, 2007, 155926). create water soluble organic carbon (WSOC)
measurement techniques (Andracchio et al., 2002, 155657; Yang et al., 2003, 156167). develop
semi-continuous/continuous/real-time carbon measurement techniques (Chow et al., 2008, 156355;
Watson et al., 2005, 157125). and introduce isotope identification into the OC/EC measurement
(Huang et al., 2006, 097654).
      OC sampling artifact issues were further addressed in various studies (Arhami et al., 2006,
156224; Bae et al., 2004, 156243; Chow et al., 2005, 155728; Fan et al., 2003, 058628; Fan et al.,
2004, 155770; Grover et al., 2008, 156502; Lim et al., 2003, 037037; Mader et al., 2003, 155955;
Matsumoto et al., 2003, 124293; Muller et al., 2004, 097109; Offenberg et al., 2007, 098101; Olson
and Norris, 2005, 156005; Park et al., 2006, 098104; Rice, 2004, 156049; Subramanian et al., 2004,
081203; ten Brink et al., 2004, 097110; ten Brink et al., 2005, 156115; Viana et al.,  2006, 179987).
and were well summarized by Watson et al. (2005, 157125) and Chow et al. (2008,  156355). There
are two commonly used methods to  correct OC sampling artifacts: the filter with backup filter
system (TBQ: placing a backup quartz-fiber filter behind the front Teflon-membrane filter; QBQ:
placing a backup quartz-fiber filter behind the front quartz-fiber filter); and the
denuder-filter-adsorbent system. Subramanian et al. (2004, 081203) and Chow et al. (2006, 099031)
reported that during the Pittsburgh and Fresno supersite studies the positive artifact (organic gases
condensed on filters) from TBQ (24-34%, up to 4 (ig/m3 OC) was nearly twice that from QBQ
(13-17%). With the denuder-filter-adsorbent system, the negative artifact (OC evaporating from the
filter) was 5-10%. Watson and Chow (2002, 037873) reported that the XAD-coated denuder could
function as efficiently as a parallel plate denuder using carbon-impregnated charcoal filters (GIF)
with frequent denuder changes. Huebert and Charlson (2000, 156577) reported that using tandem
filter packs may hinder a quantitative analysis of the artifacts.
      Different temperature protocols and optical correction methods in thermal-optical analyses
were further evaluated by Watson et al.  (2005, 157125). Chow  et al. (2004, 156347; 2005, 155728;
2007, 156354). Subramanian et al. (2006, 156107). Conny et al. (2003, 145948). Han et al. (2007,
155823). Chen et al. (2004, 199501) and (Conny et al., 2009, 191999). Solomon et  al. (2003,
156994) reported a 20-50% difference for OC and a 20-200% difference for EC using  11 filter
samples and 4 different analytical protocols. In an assessment of the different thermal-optical
analysis protocols used around the world, Watson et al. (2005, 157125) reported that differences of a
factor of 2 to 7 in EC between different methods could be observed, and a factor of 2 was  common,
while the relative differences in OC  between different methods were small. As Watson et al. (2005,
157125) stated, there are 12 major differences among the thermal methods: (1) analysis atmosphere;
(2) temperature ramping rates; (3) temperature plateaus; (4) residence time at each plateau; (5)
optical pyrolysis monitoring configuration and wavelength; (6) standardization;  (7) oxidation and
reduction catalysts; (8) sample aliquot and size; (9) evolved carbon detection method; (10) carrier
gas flow through or across the sample; (11) location of the temperature monitor relative to the
sample; and (12) oven flushing conditions. Chow et al. (2004, 156347) and Chen et al. (2004,
199501) addressed the difference between optical transmission and optical reflectance methods for
charring correction, and they reported that the charring OC on the surface of or inside a filter
dominated the differences between these two correction methods. The differences between different
sampling and measurement methods are also applied to the in-situ/semi-continuous methods, since
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most of these methods are also based on thermal-optical analysis of collected filters. Most of these
methods agree with integrated filter methods within 30%.
      The differences observed between methods for OC and EC come largely from how OC and
EC are defined. They are defined on an operational basis, as there are no standard reference
materials. Initial efforts have been made to produce OC/EC reference materials at the National
Institute of Science and Technology (NIST) (Klouda et al., 2005, 130382: Lee, 2007, 155926).
Klouda et al. (2005, 130382) described the development of Reference Material 8785: Air Particulate
Matter on Filter Media. Each reference filter is uniquely identified by its air PM number and its
gravimetrically determined mass of fine Standard Reference Material (SRM) 1649a, and each filter
has values assigned for total carbon, EC, and organic carbon mass fractions measured according to
both IMPROVE and NIOSH protocols. Lee et al. (2007, 155926) reported a method to create a
reference filter with a known amount of OC (as potassium hydrogen phthalate), and EC (as carbon
black hydrosol).
      Measurement methods for WSOC have been developed recently (Miyazaki et al., 2006,
156767: Sullivan  and Weber, 2006, 157031: Sullivan et al., 2004, 157029: Sullivan et al., 2006,
157030: Sullivan et al., 2007, 100083: Yu et al., 2004, 156172). WSOC can be measured on
integrated filter samples, or in-situ measurement can be conducted by coupling with the PILS-IC
(Sullivan et al., 2004, 157029). For  integrated filter samples, filters are extracted with deionized
water and followed by oxidation of  total WSOC to CO2. CO2  can then be detected by either infrared
spectroscopy (IR) (Decesari et al., 2000, 155748: Kiss et al., 2002,  156646: Yang et al., 2003,
156167). FID (Yang et al., 2003, 156167). or pyrolysis gas chromatography/mass spectrometry
(GC/MS) (Gelencser et al., 2000, 155785). A correlation coefficient of 0.84 was reported by Sullivan
et al. (Sullivan et al., 2004, 157029) between in-situ and filter based measurement of WSOC.
      Further development and evaluation has been conducted on the measurement of BC with light
absorption instruments (Andreae and Gelencser, 2006, 156215: Amort et al., 2003, 037711: Bae et
al., 2004, 156243: Borak et al., 2003, 156284: Cyrys et al., 2003, 049634: Kurniawan and Schmidt-
Ott, 2006, 098823: Park et al., 2006, 098104: Saathoff et al., 2003,  156066: Sadezky et al., 2005,
097499: Slowik et al., 2007, 096177: Taha et al., 2007, 096277: Virkkula et al., 2007, 157098:
Wallace, 2000, 000803: Weingartner et al., 2003, 156149: Williams et al., 2006, 157148: Wu et al.,
2005, 157155). These instruments include the aethalometer, particle absorption photometer, and
photoacoustic analyzer. However, these instruments are subject to interferences by particle
scattering, interactions with the filter substrate, particle loading on filters, and other pollutants (e.g.,
NO2). Uncertainties of up to 50% were observed in the studies mentioned above by comparing these
methods with integrated filter methods and thermal analysis methods.
      Huang et al. (2006, 097654) reported the measurement  of a stable isotope,  13C, in OC and EC
with a thermal optical transmission  analyzer coupled with gas chromatography-isotope ratio mass
spectrometer (TOT-GC-IRMS). The ratio of 13C/ 2C in OC and EC can provide useful information on
OC/EC source categories and origin. The method was applied to Pacific2001 aerosol  samples from
the greater Vancouver area in Canada and produced a precision of-0.03%. Gustafsson et al. (2009,
192000) applied the radiocarbon measurement technique and  quantified the source contributions of
carbonaceous aerosols to the Indian Ocean "brown cloud," with particular relevance for
understanding and mitigating the climate effects of EC/BC.


      Organic Speciation

      Organic matter makes up a substantial  fraction of PM in all regions of the U.S.  (U.S. EPA,
2004, 056905). and 10-40% of the total organic matter is currently quantifiable at the individual
compound level (Poschl, 2005, 156882). Recent advancements in traditional solvent extraction
GC/MS and high pressure liquid chromatography (HPLC) as  well as application  of thermal
desorption (TD) techniques are helping to expand the understanding of the composition of organic
matter as well  as improving detection limits for quantification of organic molecular marker (OMM)
compounds (Robinson et al., 2006,  156918: Schnelle-Kreis et al., 2005, 112944:  Sheesley et al.,
2007, 112017: Shrivastava et al., 2007, 111594). In addition, information about organic functional
groups can be obtained with Fourier transform infrared spectrometry (FTIR) (Tsai and Kuo, 2006,
156127).
      Recent advancements in GC/MS technology including inert electron ionization sources and
improved instrument sensitivity and scan rates for better OMM quantification, have increased its
December 2009                                 3-27

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application in organic aerosol characterization studies (Cass, 1998, 155716; Dutton et al., 2009,
194887; Fraser et al., 2003, 042231; Graham et al., 2003, 156489; Hays et al., 2002, 026104;
Robinson et al., 2006, 156918; Schauer et al., 1996, 051162; Sheesley et al., 2007, 112017;
Subramanian et al., 2006, 156107; Watson et al., 1998, 012257; Zheng et al., 2002, 026100; Zheng et
al., 2006, 157189).  Incorporation of high volume injection using programmable temperature
vaporization (PTV) (Engewald et al., 1999, 155765) has further lowered detection limits for trace
level OMM compounds. High volume injection has the added benefit of preventing the loss of
semivolatile compounds (Swartz et al., 2003, 157035). and has been applied for analysis of PAHs
using low volume samplers (down to 5 L/min), allowing for smaller required mass loadings (Bruno
et al., 2007, 155706; Crimmins  and Baker, 2006, 097008). Since last review, HPLC analysis with
fluorescence detection has also been used frequently for quantification of semivolatile organic
compounds in both the particle and gas phase (Albinet et al., 2007, 154426; Barreto et al., 2007,
155676; Chow, 2007, 157209; Eiguren-Fernandez et al., 2003, 142609; Goriaux et al., 2006, 156484;
Murahashi, 2003, 096539; Ryno et al., 2006, 156065; Stracquadanio et al., 2005,  156104; Temime-
Roussel et al., 2004, 098530; Temime-Roussel et al., 2004, 098521). Lengthy extraction and analysis
times remain a limiting factor for these methods.
     TD techniques bypass one of the time consuming steps in traditional solvent extraction
analysis for nonpolar organic compounds (n-alkanes, branched alkanes, cyclohexanes, hopanes,
steranes, alkenes, phthalates and PAHs). This is achieved by vaporizing and analyzing organic
constituents directly from the collection substrate, thereby bypassing the extraction step (Chow,
2007, 157209). Methods exist for both off-line TD analysis of previously collected filter samples and
semi-continuous TD analysis. Annex A, Table A-17 is adapted from Chow et al. (2007, 157209) and
summarizes recent  TD-GC/MS studies. The most common off-line method is TD-GC/MS  (Hays  and
Lavrich, 2007, 155831).  Continuous or semi-continuous methods have been developed for direct
analysis of individual organic constituents by coupling TD with various forms of mass spectrometry
(Smith et al., 2004, 156090; Tobias and Ziemann, 1999, 157053; Tobias et al.,  2000, 156121; Voisin
et al., 2003, 156141; Williams et al., 2006, 156157). A comparison of measurement and analytical
specifications for filter analysis using solvent extraction and TD methods for organic speciation are
summarized in Annex A, Table A-17.


3.4.1.3.   Multiple-Component Measurements on Individual Particles

     The 2004 PM AQCD (U.S. EPA, 2004, 056905) discussed the aerosol time-of-flight mass
spectrometry (ATOFMS). Recently, the ATOFMS and several other aerosol mass spectrometry
methods have been further developed. Both lab and field comparisons have been  conducted to
evaluate the reliability of these types of instruments.
     There are four types of commonly used aerosol mass spectrometry: (1) particle analysis by
laser MS (PALMS; National Oceanic and Atmospheric Administration [NOAA]); (2) rapid single
particle mass spectrometer (RSMS; University of Delaware); (3) aerosol time-of-flight MS
(ATOFMS; TSI, Inc.); and (4) AMS  (Aerodyne) (Chow et al., 2008, 156355; Nash et al., 2006,
199502). The differences between these instruments primarily come from the particle sizing methods
of mass spectrometers, as shown in Annex A, Table A-16. Although the technique varies, the
underlying principle is to fragment each particle into ions, using either a high-power laser or a heated
surface, and then a  mass spectrometer to measure the mass to charge ratio of each ion fragment in a
vacuum.
     These instruments were evaluated at the Atlanta, Houston, Fresno, Pittsburgh, New York, and
Baltimore supersites (Bein et al., 2005, 156265; Drewnick et al., 2004, 155755; Drewnick et al.,
2004, 155754; Hogrefe et al., 2004, 156560; Jimenez et al., 2003, 156611; Lake et al., 2003, 156669;
Lake et al., 2004, 088411; Middlebrook et al., 2003, 042932; Phares  et al., 2003,  156866; Qin  and
Prather, 2006, 156895; Wenzel et al., 2003, 157139). Measurements of the gross composition and
abundance of particles by these instruments were generally semi-quantitative, with the exception of
AMS. Particles of similar composition (e.g., OC/SO42~, Na/K/SO4 ~,  soot/hydrocarbon, and mineral
particle types) were characterized by these instruments during the studies mentioned above. NO3~
and SO4 ~  concentrations measured with AMS were comparable with other continuous and
filter-based methods, as mentioned in Section 3.4.1.2. In addition, concentrations of different particle
types can be obtained by the co-location of these aerosol mass spectrometers and other particle
sizing instruments,  such as particle counters or the Micro-Orifice Uniform Deposit Impactor
(MOUDI).
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3.4.1.4.   UFPs: Mass, Surface Area, and Number

      Instruments for measuring UPFs developed during the past decade permit measurement of size
distributions of particles down to 3 nm in diameter with mobility particle sizers. Concentrations
down to this size range can be obtained by a MOUDI. The recently developed low pressure-drop
UFP impactor coupled with a (3 Attenuation Monitor (nano-BAM) can also provide UFP (<150 nm)
mass concentrations (Chakrabarti et al, 2004, 157426). A high correlation coefficient was observed
between MOUDIs and nano-BAMs, with a correlation of 0.96. A 50% cut point (d50) of 13-200 nm
can be achieved by a high-volume slot-type UFP virtual impactor (Middha and Wexler, 2006,
155982).
      Methods are also being developed to measure the surface area of UFPs. Particle surface area is
usually measured by attaching labeled (radioactive or electrical labeling) molecules to particles and
detecting the radioactive or electrical properties  of the attached molecules. Wilson et al. (2007,
098398) suggested that the electrical aerosol detector (BAD, based on diffusion charging)
measurement might be a useful indicator of the particle surface area deposited in the  lung. This
method can be potentially useful for examining the association between health effects and particle
surface areas.
      Developments involving the condensation particle counter include use of de-ionized water as a
condensation medium in lieu of butanol or n-propanol in condensation particle counters (Hering et
al., 2005, 155838: Hermann et al., 2007, 155840: Petaja et al., 2006, 156021). This development
makes the condensation particle counter (CPC) easier to use in field studies because water does not
have some of the same chemical properties (with respect to hazard and odor) as butanol or
n-propanol. The performance of this CPC was reported to be similar to the conventional butanol
based CPC (Hering et al., 2005, 155838). Use of a battery of water and butanol-based CPCs was
demonstrated to detect a range of solubilities in nucleation-mode particles (Kulmala et al., 2007,
155911). Additionally, CPCs have been used to measure particles in the smaller end of the UF scale
through adjustment of CPC cut-off diameters through tuning the temperature difference between the
CPC saturator and condenser (Kulmala et al., 2007, 155911) and improved charge reduction
techniques (Winkler et al., 2008, 156160). The latter method was effective in reducing the size of
particles detected by a CPC to <2 nm. These studies include assessment of errors related to these
developments with the CPC and generally show that counting efficiencies with these devices is
upwards of 95% (Hermann et al., 2007, 155840). Additionally, recent advancements have been made
in development of fast scanning methods for UFP size distributions, including diffusion screens (DS)
(Feldpausch et al., 2006, 155773) and fast integrated mobility scanners (FIMS) (Olfert et al., 2008,
156004).


3.4.1.5.   PM Size Distribution

      Along with particle density and shape (U.S. EPA, 2004, 056905). the particle size distribution
can be used to estimate PM mass concentrations. For particles >0.1 (im, several instruments,
including DRUM, MOUDIs, and aerodynamic particle sizer (APS), are available to measure
mass-based or count-based particle size distribution.  An APS incorporating very sharp cut points
between 0.1  and 10 urn is now available (Peters, 2006, 156860: Zeng, 2006, 098375). For particles
in this range, inertial forces are used to separate  particles based on impaction. For particles <0.1 (im,
particles can be separated by their electrical mobility, and as a result, electrical mobility diameter is
often used to describe UFP size distribution in lieu of aerodynamic diameter. It has been necessary to
develop techniques to convert mobility diameters, measured by the scanning mobility particle sizer
(SMPS) or the Engine Exhaust Particle Sizer (EEPS), to aerodynamic diameters, measured by the
APS, or vice versa, in order to merge the distributions spanning the UF, accumulation, and coarse
modes. A variety of techniques for combining SMPS and APS diameters have been reported in the
literature (Hand and Kreidenweis, 2002, 155824: Khlystov et al., 2004, 155897: Morawska et al.,
1999, 007609: Morawska et al., 2007, 155990: Shen et al., 2002, 156086: TSI, 2005, 157196).
However, each of these techniques incurs some uncertainty of which the user must be aware.


3.4.1.6.   Satellite Measurement

      Instruments sensing back scattered solar radiation on satellites have made it possible to derive
information about tropospheric aerosol properties on the global scale. The satellite borne instruments
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vary in their complexity and in the aerosol properties they can measure. Satellite instruments
measure radiance (or brightness temperature) that can then be used to provide information on the
aerosol column amount, or the aerosol optical depth (AOD). Depending on the wavelengths sampled
and the spectral resolution of the instruments, information about the composition of particles of
diameter <2 (im and particles of diameter >2\am can be obtained. Data from two main instruments,
the moderate resolution imaging spectroradiometer (MODIS) and the multiangle imaging
spectroradiometer (MISR) have been used to estimate surface PM in the U.S. MODIS measures the
intensity of back scattered sunlight at seven wavelengths through the visible to the near infrared at
one viewing direction; and MISR measures the intensity at four wavelengths (from the visible to the
near IR) and the same ground pixel at nine viewing angles. The spatial resolution of reported AOD is
17.6x17.6 km for MISR and either 10^10 or 1x1 km for MODIS, depending on retrieval algorithm.
Since both instruments are located on the same satellite, their times of overpass are the same, about
1330 local time. Due to precession of the satellite's orbit, the satellite does not pass over the same
path every day, and instruments cannot sense aerosol properties beneath cloud tops.
      The problem of using satellite data to retrieve properties of the atmospheric aerosol is complex
because the surface contribution to satellite measured reflectance must be separated from the aerosol
signal. Difficulties can arise when attempting to derive aerosol information over land surfaces
because of uncertainties in surface reflectivity, similarities between aerosol and surface composition,
and high signal-to-noise ratio when viewing AOD over reflective surfaces such as desert and snow.
To overcome this difficulty, data from MODIS have been applied over dark land surfaces and
ongoing improvements in retrieval algorithms are being developed. Instruments such as the MISR
that sense  at multiple viewing angles can better cope with the problems over land surfaces because
they can use the information on the angular dependence of reflection from the surface and the
atmosphere to  distinguish between their signals. Not only can total AODs be derived, but fractional
AODs that reflect external mixtures characterized by particle shape, effective radius, and single
scattering  albedo can also be derived. These properties can then be used to infer particle
composition. Retrievals over the oceans have had less difficulty because the optical  properties of
sunlight reflected from the sea surface are much better known, and reflectivities are low over most
zenith angles at less than gazing incidence.
      Kokhanovsky et al. (2007, 190009) examined the errors associated with MODIS, MISR, and a
number of other satellite instruments with respect to associated retrieval algorithms for retrievals
over Central Europe. They found a correlation coefficient between MODIS and MISR AOD of 0.62.
Both MODIS and MISR AOD tended to underestimate ground-based AOD measurements from
AERONET (NASA's AErosol RObotic NETwork) slightly with MODIS generally retrieving higher
AODs than MISR. Chu et al. (2003, 190049) found correlations between MODIS and AERONET
AODs ranging from 0.82-0.91; and Kahn et al. (2005, 189961) found correlations of 0.7-0.9 between
MISR and AERONET AODs.
      Further complexity is added when attempting to relate surface PM2 5 to aerosol optical depths.
The detailed comparisons of surface measurement and satellite measurements are given in Chapter 9.


3.4.2.  Ambient Network  Design



3.4.2.1.   Monitor Siting Requirements

      The EPA Air Quality System database (AQS) contains measurements of air pollutant
concentrations in the 50 states, plus the District of Columbia, Puerto Rico, and the Virgin Islands, for
the 6 criteria air pollutants as well as a more limited dataset of hazardous air pollutants. In 2007,
there were 4,693 PMi0 monitors and 2,194 PM2.5 monitors reporting values to the AQS. Where
SLAMS PMio  and PM25 monitoring is required, at least one of the sites must be a maximum
concentration site for that specific area. The appropriate spatial scales for PM2 5, PMi0_2.5, and PMi0
monitoring differ given the contrasting  spatial gradients of coarse PM relative to fine. The relevant
scales for  each size classification are provided in Annex A, Table A-18.
      Criteria for siting ambient monitors for PM at national monitoring networks are summarized
below by PM size, and details  are given in the CFR 40 Part 58 Appendix D, and
SLAMS/NAMS/PAMS Network Review Guidance (U.S. EPA, 1998, 093211). Table A-19 in Annex
A provides a summary of the number of sites and operating specifications of these networks.  Probing
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and monitoring path siting criteria for any specific monitoring site are given in CFR 40 Part 58
Appendix E, including horizontal and vertical placement, spacing from minor source, spacing from
obstructions, spacing from trees, and spacing from roadways.

      PM2.5

      The minimum number of PM2.5 monitors required in a metropolitan statistical area is
determined by the population and the air quality in the area, as specified in Appendix D of 40 CFR
Part 58. The required minimum number of PM25 monitors ranges from 0 to 3 in any given
metropolitan statistical area. Continuous PM2.5 monitors must be operated in no fewer than one-half
of the minimum required sites in each area. Most PM25 monitoring in urban areas should be
representative of a neighborhood scale (for trends and compliance with standards). Urban or regional
scale sites are located to characterize regional transport of PM25. In certain instances where
population-oriented micro- or middle-scale PM2 5  monitoring are determined by the Regional
Administrator to represent many such locations throughout a metropolitan area, these smaller scales
can be considered to represent community-wide air quality. PM2 5 measurements are obtained at local
temperature and pressure across the NAMS/SLAMS networks (40 CFR Part 58).
      PM25 chemical speciation monitoring  is currently conducted at 197 CSN sites
(http://www.epa.gov/ttn/amtic/specgen.html). Within the CSN network, 53 locations are recognized
as the Speciation Trends Network (STN) operating on a sample schedule of one in every three days,
while the rest of the CSN typically operates every sixth day.

      PMlO-2.5
      PM10_2.5  monitoring has not been required at SLAMS sites, but will be required at NCore1
Stations (which is a sub-set of the SLAMS) by January  1, 2011. Middle and neighborhood scale
measurements are the most important station classifications for PMi0_2.5 to assess the variation in
coarse particle concentrations that would be  expected across populated areas that are in proximity to
large emissions sources. PMi0_2.5 chemical speciation monitoring and analyses will also be required
at NCore sites by January 1, 2011. EPA has already approved FRMs and FEMs for PMi0_2.5 mass;
however, methods for PM10_2.5 speciation are still being developed (Henderson, 2009, 192001). PM10_
2.5 measurements are  obtained at local temperature and pressure by recalculating the co-located PMi0
for local conditions.
      PM
         10
      As for PM25, the minimum number of PMi0 monitors required in a metropolitan statistical area
is determined by the population and the air quality in the area, as specified in Appendix D of 40 CFR
Part 58. The required minimum number of PMi0 monitors ranges from 0 to 8 in any given
metropolitan statistical area. Except for some circumstances where microscale (<100 m, for
maximum PMi0 exposure) monitoring may be appropriate, the most important scales to characterize
the emissions of PMi0 effectively from both mobile and stationary sources are the middle scale (for
short-term public exposure) and neighborhood scale (for trends and compliance with standards).
PMio measurements are obtained at standard temperature and pressure across the NAMS/SLAMS
networks (40 CFR Part 58).


3.4.2.2.   Spatial and Temporal Coverage


      Locations of PM2.5 and PM10 Monitors in Selected Metropolitan Areas in the U.S.

      Fifteen metropolitan regions were chosen for closer investigation of monitor siting based on
their distribution across the nation and relevance to health studies analyzed in subsequent chapters of
this ISA. These regions were: Atlanta, Birmingham, Boston,  Chicago, Denver, Detroit, Houston, Los
Angeles, New York City, Philadelphia, Phoenix, Pittsburgh, Riverside, Seattle, and St. Louis. Core-
1 For more information on NCore, see the NCore web site at: http://www.epa.gov/ttn/amtic/ncore/index.html.
December 2009                                 3-31

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Based Statistical Areas (CBSAs) and Combined Statistical Areas (CSAs), as defined by the U.S.
Census Bureau (http://www.census.gov/), were used to determine which counties, and hence which
monitors, to include for each metropolitan region.1 Figure 3-7 and Figure 3-8 display PM2.s and PMi0
monitor density, respectively, with respect to population density in Boston. Annex A includes similar
information for all fifteen metropolitan regions (Figure A-l through Figure A-30).
1 A CBSA represents a county-based region surrounding an urban center of at least 10,000 people determined using 2000 census data and
 replaces the older Metropolitan Statistical Area (MSA) definition from 1990. The CSA represents an aggregate of adjacent CBSAs tied
 by specific commuting behaviors. The broader CSA definition was used when selecting monitors for the cities listed above with the
 exception of Los Angeles, Riverside and Phoenix. Los Angeles and Riverside are contained within the same CSA, so the smaller CBSA
 definition was used to delineate these two cities. Phoenix is not contained within a CSA, so the smaller CBSA definition was used for
 this city as well.
December 2009                                       3-32

-------
                   Boston Combined Statistical Area
                        i Kilometers
       0  5 10  20  30  40  50
       ol\
          r
      2005 Population Density
      [    | Boston PM2.5 Monitors (15km buffer)
      Population per Sq Km
      ^B 0-251
      ^H 252 - 502
           503 - 2508
           2509-5016
      ^B 5017-12539
      ^H 12540-50155
                           : Kilometers
       0 15 30  60  90  120  150
Figure 3-7.    PM2.s monitor distribution in comparison with population density, Boston CSA.
December 2009
3-33

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                  Boston Combined Statistical Area
                        i Kilometers
       0 5 10  20  30  40  50
       ol\
          r
      2005 Population Density
      [    | Boston PMio Monitors (15 km buffer)
      Population per Sq Km
      ^B 0-251
      ^H 252 - 502
           503 - 2508
           2509-5016
      ^B 5017-12539
      ^H 12540-50155
                          : Kilometers
       0 15 30  60  90  120  150
Figure 3-8.    PM10 monitor distribution in comparison with population density, Boston CSA.
December 2009
3-34

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Table 3-3.
Proximity to PM^and PMio monitors for total population3 by city.
Proximity to PM Monitors'5
Region
Total CSA/CBSA
N
<1km
N %
<5km
N %
<10km
N %
<15km
N %
PROXIMITY TO PM2.5 MONITORS
Atlanta
Birmingham
Boston
Chicago
Denver
Detroit
Houston
Los Angeles
New York
Philadelphia
Phoenix
Pittsburgh
Riverside
Seattle
St. Louis
5,316,742
1,166,100
7,502,707
9,754,262
2,952,039
5,553,465
5,503,320
13,061,361
22,050,940
6,388,913
3,818,147
2,515,383
3,781,063
3,962,434
2,869,955
23,461 0.44
12,925 1.11
185,457 2.47
177,076 1.82
40,601 1.38
54,997 0.99
11,586 0.21
115,477 0.88
717,094 3.25
117,389 1.84
37,133 0.97
40,574 1.61
43,739 1.16
13,723 0.35
37,329 1.30
581,461 10.94
240,383 20.61
1,877,180 25.02
3,091,573 31.69
649,953 22.02
1,174,733 21.15
213,708 3.88
2,579,809 19.75
8,107,764 36.77
1,878,373 29.40
490,072 12.84
587,148 23.34
723,829 19.14
287,373 7.25
563,176 19.62
1,990,477 37.44
666,926 57.19
3,356,019 44.73
6,473,463 66.37
1,548,976 52.47
2,791,555 50.27
905,007 16.44
7,544,466 57.76
13,493,867 61.19
3,517,321 55.05
1,099,069 28.79
1,331,230 52.92
1,855,296 49.07
931,630 23.51
1,338,349 46.63
3,179,844 59.81
848,447 72.76
4,641,175 61.86
8,185,010 83.91
2,252,657 76.31
3,845,190 69.24
1,599,079 29.06
10,792,727 82.63
16,571,764 75.15
4,393,136 68.76
1,739,542 45.56
1,883,301 74.87
2,344,394 62.00
1,561,792 39.41
1,760,985 61.36
PROXIMITY TO PM10 MONITORS
Atlanta
Birmingham
Boston
Chicago
Denver
Detroit
Houston
Los Angeles
New York
Philadelphia
Phoenix
Pittsburgh
Riverside
Seattle
St. Louis
5,316,742
1,166,100
7,502,707
9,754,262
2,952,039
5,553,465
5,503,320
13,061,361
22,050,940
6,388,913
3,818,147
2,515,383
3,781,063
3,962,434
2,869,955
30,973 0.58
23,943 2.05
63,614 0.85
55,642 0.57
38,449 1.30
14,050 0.25
36,795 0.67
52,052 0.40
19,842 0.09
23,988 0.38
99,520 2.61
65,906 2.62
61,356 1.62
4,851 0.12
27,872 0.97
416,440 7.83
251,310 21.55
1,090,172 14.53
844,714 8.66
521,201 17.66
309,623 5.58
832,767 15.13
1,404,389 10.75
292,105 1.32
376,966 5.90
1,255,430 32.88
706,413 28.08
895,615 23.69
220,539 5.57
380,411 13.25
1,090,497 20.51
473,054 40.57
2,087,770 27.83
2,374,972 24.35
1,146,286 38.83
748,971 13.49
2,227,314 40.47
4,899,254 37.51
592,631 2.69
1,091,532 17.08
2,615,738 68.51
1,291,700 51.35
2,360,272 62.42
709,887 17.92
891,695 31.07
1,837,983 34.57
638,472 54.75
2,939,870 39.18
3,844,297 39.41
1,799,187 60.95
1,300,995 23.43
3,141,150 57.08
9,075,863 69.49
773,962 3.51
2,238,309 35.03
3,416,682 89.49
1,705,451 67.80
2,922,799 77.30
1,211,430 30.57
1,212,543 42.25
3Based on 2005 population totals.
Percentages are given with respect to the total population per city provided.
December 2009
3-35

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      Table 3-3 shows the population density around PM2.5 and PM10 monitors for the total
population for each CS A/CBS A individually. Population totals within various distances of PM
monitors were calculated assuming equal internal population distribution for individual census
blocks. Between-city disparities in population density were large and were dependent primarily on
the location and number of PM monitoring sites per CSA/CBSA. For PM2.5, Los Angeles (83%) and
Denver (76%) had the largest proportion of the total population within 15 km of a monitor. Houston
(29%) had the least population coverage with their PM2.5 monitors. For PM10, Phoenix (89%) had the
largest proportion of the total population within 15 km of a monitor.  Detroit (23%), Boston (39%),
Seattle (31%), and Philadelphia (35%) had the smallest proportions of the population within 15 km
of a PMio monitor. Proximity to monitoring stations is considered further in Section 3.5 and Section
3.8 regarding spatial variability within cities. Figure 3-7 shows that the PM2.5 network more closely
samples near population centers in the Boston CSA compared with the PMi0 network shown in
Figure 3-8, although both PM2 5 and PM10 networks place at least one monitor in the city center.


3.4.2.3.   Network Application for Exposure Assessment with  Respect to Susceptible
          Populations


      Subject Age

      Table 3-4 breaks down the population density around PM2 5 and PMi0 monitors for
sub-populations of children age 0-4 yr, children age 5-17 yr, and elderly adults age 65 yr and over
cumulatively for the 15 CS As/CBS As examined.  Table 3-5 shows the distribution for adults age 65
years and over for each CSA/CBSA individually. This detail of information is not provided for the 0-
to 4-yr and 5- to 17-yr age groups because variation in percentage within a certain radius of the
monitor was generally fairly low for each city across the child age groups when compared to total
population. In the cases of Denver, Detroit, Phoenix, Riverside, and St. Louis for PM25 and
Birmingham, Denver, Riverside, and St. Louis for PMi0, the elderly population's distribution around
the samplers varied more from the total population compared to other age groups. When all
CS As/CBS As were considered cumulatively, the percentage of the population within 15 km of a
monitor was similar for all  age groups for both PM2 5 and PMi0. Between-city disparities in elderly
population density within a sampler radius were larger. For PM2 5, Chicago  (87%) and Denver (84%)
had the largest proportion of the elderly population within 15 km of a monitor. Houston (31%) had
the least population coverage with their PM2 5 monitors. For PMi0, Phoenix (90%) had the largest
proportion of the total population within 15 km of a monitor. New York (4%), Detroit (27%),  Seattle
(32%), and Philadelphia (39%) had the smallest proportions of the population within 15 km of a
PMio monitor. These differences may reflect overall density of the samplers within a given city, with
PM25 monitors more numerous than PM10 monitors in most of the CS As/CBS As, and retirement and
settlement trends among elderly adults.
December 2009                                 3-36

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Table 3-4.     Proximity to PM2.6 and PMio monitors for children age 0-4 yr, children age 5-17 yr, and
             adults age 65 yrand older.3 The figures presented here are cumulative for the 15
             CSAs/CBSAs examined in Chapter 3.

Age
Grouping

Proximity to PM Monitors'5
Total CSA/CBSA
N
<1
N
km
%
<5km
N
%
<10km
N
%
<15km
N
%
PROXIMITY TO PM2.s MONITORS
0-4
5-17
>65
6,400,785
17,212,825
10,391,023
109,466
275,427
175,113
1.71
1.60
1.69
1,603,000
4,164,132
2,570,909
25.04
24.19
24.74
3,361,922
8,814,179
5,483,776
52.52
51.21
52.77
4,462,403
11,813,997
7,288,049
69.72
68.63
70.14
PROXIMITY TO PM10 MONITORS
0-4
5-17
>65
6,400,785
17,212,825
10,391,023
44,384
110,882
68,367
0.69
0.64
0.66
695,120
1,756,246
1,056,375
10.86
10.20
10.17
1,725,419
4,441,239
2,631,243
26.96
25.80
25.32
2,636,782
6,942,001
4,041,802
41.19
40.33
38.90
  Based on 2000 population totals.
  Percentages are given with respect to the total population per city provided.


      Race and Hispanic Origin

      Table 3-6 shows the percent of the population self-identified as white or black and having a
Hispanic or non-Hispanic origin within 1,5, 10, or 15 km distances from PM25 and PMio monitors
cumulatively across the fifteen CSAs/CBSAs. For PM2.5, blacks and Hispanics had similar
percentages of the population within 15 km of a monitor (86% and 82%, respectively), while a
smaller proportion of whites and non-Hispanics were within that same distance (63% and 67%,
respectively), across the fifteen CSAs/CBSAs studied. For PM^ Hispanics (54%) represented the
subpopulation with the largest percentage of total population within 15 km of a monitor across the
fifteen CSAs/CBSAs studied. The percentage of blacks within that same distance was marginally
lower (48%), whereas the percentage of whites and non-Hispanics within 15 km of a monitor was
approximately two-thirds that of Hispanics (35% and 37%, respectively). Higher percentages of
individual ethnic subpopulations within 15 km of a PM2.5 monitor most likely represents the fact that
more PM2 5 monitors  are currently deployed compared with PMio monitors. While no ethnic
subpopulation appears to be well represented at the neighborhood scale, greater percentages of the
black and Hispanic populations (1% each) are within 1 km of a PMio monitor than the corresponding
white and non-Hispanic populations (0.5% each). Likewise, 2.5% of the black population and 2.8%
of the Hispanic population reside within 1 km of a PM25 monitor compared to 1.4% of the white
population and 1.5%  of the non-Hispanic population. Furthermore, it is notable that at any scale
shown in Table 3-6 for both PM25 and PMio monitors, those self-identified as black or Hispanic
actually have greater  representation by the monitors than those identified as white or non-Hispanic.
December 2009
3-37

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Table 3-5.
Proximity to PM2.eand PMio monitors for adults age 65 yr and older3 by city.
Proximity to PM Monitors'5
Age Grouping

Total CSA/CBSA
N
<1km
N

%
<5km
N

%
<10km
N

%
<15
N
km
%
PROXIMITY TO PM2.5 MONITORS
Atlanta
Birmingham
Boston
Chicago
Denver
Detroit
Houston
Los Angeles
New York
Philadelphia
Phoenix
Pittsburgh
Riverside
Seattle
St. Louis
362,201
145,905
945,790
1,018,983
232,974
626,216
377,586
1,207,436
2,710,675
834,110
388,150
449,544
342,334
390,372
358,747
1,757
1,619
18,821
18,539
3,891
5,765
1,010
9,653
78,918
13,323
2,738
8,933
3,024
1,721
5,401
0.49
1.11
1.99
1.82
1.67
0.92
0.27
0.80
2.91
1.60
0.71
1.99
0.88
0.44
1.51
36,772
29,952
224,628
348,656
59,625
138,672
14,911
229,893
921 ,599
251 ,459
39,833
111,050
50,901
29,429
83,528
10.15
20.53
23.75
34.22
25.59
22.14
3.95
19.04
34.00
30.15
10.26
24.70
14.87
7.54
23.28
136,179
84,223
438,920
713,194
140,523
345,808
66,741
688,844
1,619,177
487,003
90,304
249,269
129,836
101,223
192,532
37.60
57.72
46.41
69.99
60.32
55.22
17.68
57.05
59.73
58.39
23.27
55.45
37.93
25.93
53.67
207,122
106,488
606,231
883,112
196,361
469,462
117,661
984,889
2,048,842
605,663
142,084
347,711
170,933
156,562
244,929
57.18
72.98
64.10
86.67
84.28
74.97
31.16
81.57
75.58
72.61
36.61
77.35
49.93
40.11
68.27
PROXIMITY TO PM10 MONITORS
Atlanta
Birmingham
Boston
Chicago
Denver
Detroit
Houston
Los Angeles
New York
Philadelphia
Phoenix
Pittsburgh
Riverside
Seattle
St. Louis
362,201
145,905
945,790
1,018,983
232,974
626,216
377,586
1,207,436
2,710,675
834,110
388,150
449,544
342,334
390,372
358,747
2,115
3,663
6,852
7,619
3,675
1,555
2,085
4,693
2,463
2,740
8,605
13,302
4,181
503
4,316
0.58
2.51
0.72
0.75
1.58
0.25
0.55
0.39
0.09
0.33
2.22
2.96
1.22
0.13
1.20
35,448
35,628
124,911
107,540
43,658
41 ,833
57,413
126,696
37,580
49,413
119,306
133,285
65,499
22,333
55,833
9.79
24.42
13.21
10.55
18.74
6.68
15.21
10.49
1.39
5.92
30.74
29.65
19.13
5.72
15.56
93,903
66,839
262,854
291 ,705
107,548
99,680
166,715
422,725
80,222
154,535
267,456
243,723
182,615
72,979
117,743
25.93
45.81
27.79
28.63
46.16
15.92
44.15
35.01
2.96
18.53
68.91
54.22
53.34
18.69
32.82
139,240
86,299
385,046
441 ,771
168,447
167,760
219,615
810,078
104,951
322,700
348,464
314,941
236,900
123,054
172,535
38.44
59.15
40.71
43.35
72.30
26.79
58.16
67.09
3.87
38.69
89.78
70.06
69.20
31.52
48.09
+Based on 2000 population totals.
Percentages are given with respect to the
                                 total population per city provided.
December 2009
3-38

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Table 3-6.    Proximity to PM2.6 and PMio monitors based on the population identified as white, black,
            Hispanic, or non-Hispanic3. The figures presented here are cumulative for the 15
            CSAs/CBSAs examined in Chapter 3.

                                       Proximity to PM Monitors'5
Race or
Hispanic
Origin
Total CSA/CBSA
N
< 1 km < 5 km
N % N %
<10km <15km
N % N %
PROXIMITY TO PM2.5 MONITORS
White
Black
Hispanic
Non-Hispanic
61,936,855
12,668,004
15,916,208
74,611,962
863,823
320,447
445,126
1,135,999
1.39
2.53
2.80
1.52
12,257,978
4,780,620
5,782,482
16,553,574
19.79
37.74
36.33
22.19
27,553,900
9,241,172
10,661,947
36,318,474
44.49
72.95
66.99
48.68
39,030,037
10,906,346
13,094,618
49,629,054
63.02
86.09
82.27
66.52
PROXIMITY TO PM10 MONITORS
White
Black
Hispanic
Non-Hispanic
61,936,855
12,668,004
15,916,208
74,611,962
325,771
134,174
169,305
421,917
0.53
1.06
1.06
0.57
5,554,906
1,611,263
2,496,959
6,767,187
8.97
12.72
15.69
9.07
14,041,215
3,867,436
5,905,322
17,261,734
22.67
30.53
37.10
23.14
21,913,907
6,020,348
8,589,819
27,254,421
35.38
47.52
53.97
36.53
"Based on 2000 population totals
Percentages are given with respect to the total population per city provided.
      Socioeconomic Status

      Table 3-7 shows the percent of the population below and above the poverty level and the
percent of the population over age 25 years stratified by education level that reside within 1 km,
5 km, 10 km, and 15 km of a PM2.5 and PMi0 monitor cumulatively across the 15 CSAs/CBSAs. For
PM2.5, 80% of the population below poverty level and 77% of the population with less than high
school education are within  15 km of a monitor for the 15 CSAs/CBSAs studied. Populations of
those above the poverty line, those with a high school or more education, and those with a college
education within 15 km of a monitor were less than the low SES groups (67% for each). For PMi0,
47% of the population below the poverty level and  45% of the population with less than a high
school education are within  15 km of a monitor, whereas the percentage of those above the poverty
line (39%), those with a high school or more education (38%), and those with a college education
(35%) were slightly less. Higher percentages of individual SES subpopulations within a given
distance of PM2.5 monitors relative to PMi0 monitors likely reflect the fact that more PM2.5 monitors
are currently deployed within the 15 CSAs/CBSAs  studied compared with PMio monitors. Lower
SES  groups are not shown to be well-represented at the neighborhood scale, with 1.2% of the
population below the poverty level and 1.0% of the population with less than a high school education
residing within  1 km of a PMio monitor. Likewise,  3.1% of the population below the poverty level
and 2.4% of the population with less than high school education reside within 1 km of a PM25
monitor. However, the populations of low SES groups are more represented at the neighborhood
scale than those for higher SES groups. For example, only about 1.5-1.7% of those above the
poverty line, those with a high school or more education, or those with a college education are within
1 km of a PM2 5 monitor. Moreover, it is notable that at any scale shown in Table 3-7 and for both
PM2 5 and PMio, those living under the poverty line and those age 25 years and older with less than
high school education have greater representation by the monitors than those above the poverty line
or those age 25  and older with high school or college education.
December 2009
3-39

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Table 3-7.    Proximity to PM2.6 and PMio monitors based on the population below or above the
            poverty line, population over age 25 with less than high school education, population
            over 25 with high school education, and population over 25 with college education or
            more3. The figures presented here are cumulative for the 15 CSAs/CBSAs
            examined in Chapter 3.
Proximity to PM Monitors'5
SES
CSM2BSA *1km *5km
N N % N %
< 10 km < 15 km
N % N %
PROXIMITY TO PM2.s MONITORS
Below poverty line
Above poverty line
Less than HS
education
HS education
College education
10,645,411
85,551,420
11,606,042
30,583,598
16,433,811
330,970
1,297,591
276,942
444,262
280,810
3.11
1.52
2.39
1.45
1.71
3,951,549
19,094,985
3,806,208
6,940,261
3,451,717
37.12
22.32
32.80
22.69
21.00
7,107,192
41,736,460
7,225,291
15,152,047
7,776,218
66.76
48.79
62.25
49.54
47.32
8,528,731
57,070,312
8,930,174
20,489,904
11,000,917
80.12
66.71
76.94
67.00
66.94
PROXIMITY TO PM10 MONITORS
Below poverty line
Above poverty line
Less than HS
education
HS education
College education
10,645,411
85,551,420
11,606,042
30,583,598
16,433,811
132,979
485,874
112,901
185,439
59,892
1.25
0.57
0.97
0.61
0.36
1,626,694
8,171,398
1,544,594
2,975,200
1,229,885
15.28
9.55
13.31
9.73
7.48
3,504,957
21,096,615
3,537,414
7,580,000
3,447,148
32.92
24.66
30.48
24.78
20.98
5,024,714
33,034,279
5,186,441
11,747,653
5,722,347
47.20
38.61
44.69
38.41
34.82
"Based on 2000 population totals
Percentages are given with respect to the total population per city provided.
3.5.  Ambient PM Concentrations
      This section describes measurements of ambient PM mass and composition made since the
2004 PM AQCD (U.S. EPA, 2004, 056905) including analyses using AQS data as well as published
findings.  Emphasis is placed on the period from 2005-2007 which incorporates the most recent
validated AQS data available at the time this document was prepared.
      When the 2004 PM AQCD (U.S.  EPA, 2004, 056905) was written, the full nationwide PM2.5
compliance monitoring network had only recently been deployed, providing three years (1999-2001)
of completed measurements. Based on observations from these first three years, the 2004 PM AQCD
(U.S. EPA, 2004, 056905) found that PM2.5 in eastern cities was generally more highly correlated
across monitoring sites than in western cities. The higher spatial correlations  in the eastern cities
resulted from the more regionally  dispersed sources of PM25 in the East. Although PM2.5
concentrations at sites within an urban area can be highly correlated, significant differences in
concentrations can occur on any given day. The ratio  of PM25 to PMio was found to be higher in the
East than in the West in general, and values for this ratio are consistent with those found in numerous
earlier studies presented in the 1996 PM AQCD (U.S. EPA, 1996, 079380). Differences in the
composition of PM25 between eastern and western cities were also found to be consistent with
differences found in the 1996 PM AQCD (U.S. EPA,  1996, 079380). Much more limited data were
December 2009
3-40

-------
available for describing the spatial variability of coarse particulate mass measured as PM10_2 5, UFPs,
and PM composition. The 2004 PM AQCD (U.S. EPA, 2004, 056905) noted that components
produced by area (e.g., traffic) and point sources are more spatially variable than regionally
dispersed components (e.g., secondary SO42~). Spatial variability will affect estimates of community-
scale human exposure and caution should be exercised in extrapolating conclusions from one area to
another, particularly on a regional scale.
      For this PM ISA, the PM2.5 monitoring network has been active for 8 or 9 years depending on
location. Observations and analyses based on PM2.5 measurements reported to AQS are included in
this chapter. Furthermore, by selecting locations where PMi0 and PM2.5 measurements  are
co-located, information about the spatiotemporal distribution of the PMi0_2.5 size fraction is
investigated. Given the form of the current standard and the relative abundance of PMi0 monitors in
the AQS network, PMi0 mass concentrations are also included in this section with  the understanding
that PM10 includes mass contributions from the smaller size fractions and therefore overlaps with
PM2 5, PMio_2.5 and UFP mass concentrations. Although compliance monitoring does not apply for
UFPs because there is no ambient standard for them, new observational information is available
from detailed studies in several cities. Similarly, advancements have been made in understanding PM
composition from the CSN and IMPROVE networks. Descriptions of UFPs and speciated PM are
covered throughout this section where information is available.
      Unless otherwise specified, the PM2 5, PM10_2.5 and PM10 data utilized in this section comes
from the AQS. Based on the population and exposure requirements for monitor siting in 40 CFR Part
58 described in Section 3.4.2, monitors reporting to the AQS are not uniformly distributed across the
U.S. Monitors are far more abundant in urban areas than rural ones, so actual rural spatiotemporal
distributions may differ considerably from those reported here. Furthermore, biases exist for some
PM constituents (and hence, total mass) owing to volatilization losses of NO3~ and other
semi-volatile compounds and, conversely, retention of particle-bound water with hygroscopic
species. The magnitude of these effects is likely to be region-specific.
      Spatial distributions of PM across a range of geographic scales are covered in Section 3.5.1.
Temporal behavior including trends, seasonality and hourly variability are covered in Section 3.5.2.
Finally, statistical associations between different size fractions of PM and copollutants including CO,
NO2, O3 and SO2 are covered in Section 3.5.3.


3.5.1.   Spatial Distribution

      Spatial scales of interest for PM range from global and continental scales (>1000 km) down to
micro scale (-5-100 m). Variation in PM concentration depends on the spatial scale and magnitude
of PM sources,  formation and removal mechanisms, and transport and dispersion of PM. These
different sources and processes can cause substantial variation in particle size distribution and
chemistry. This section addresses the spatial variability of PM by focusing primarily on AQS data
across three different scales: variability across the U.S., urban-scale variability and neighborhood-
scale variability. These sections are further subdivided to the extent possible into PM size fractions
and composition.
December 2009                                  3-41

-------
3.5.1.1.   Variability across the U.S.
      PM;
         2.5
      Figure 3-9 shows the 3-yr mean of the 24-h PM2.5 concentrations by county across the U.S. for
2005-2007. The data used in generating this map are from FRM or FRM-like1 data obtained fromthe
AQS database after applying a completeness criterion of 75% per quarter (i.e., 11 out of 15 quarterly
measurements for a l-in-6 day sampling schedule).  Counties shown in white did not contain
sufficient PM2.5 data between  2005-2007 to meet the completeness criterion as a result of either a
lack of monitoring sites or a lack of adequate or complete data from existing monitoring sites within
the county. Of the 3,225 U.S.  counties, 540 (17%) had PM2.5 data meeting the completeness criterion
in all three years (2005-2007). These 540 counties represent roughly 63% of the U.S. population.
The fraction of the population residing within each county-average concentration range is shown on
the left-hand margin of Figure 3-9. Given the number of counties with no data, the varying size of
counties, and the non-uniform spacing of the monitors and population within each reporting county,
this should only be taken as a  rough estimate of the  relationship between population and average
ambient concentrations. As seen in Figure 3-9,Kern County, CA reported the highest 3-yr avg 24-h
PM2.5 concentration in excess  of 20 ug/m3. Average concentrations between 18 and 20 (ig/m were
reported for several counties in the San Joaquin Valley and inland southern California as well as
Jefferson County, AL containing Birmingham and Allegheny County, PA containing Pittsburgh.
1 FRM-like refers to PM2.5 concehntration data associated with the parameter code "88502 - Acceptable PM2.5 AQI and Speciation Mass"
 in the AQS. These data were collected by continuous instruments which are not approved as FRM or FEM, and consequently EPA does
 not use these data for regulatory purposes. These data are denoted as "FRM-like" because state and local monitoring agencies have
 individually decided that the continuous instruments reporting these data have a degree of agreement with FRM/FEM methods that is
 sufficient in their opinion for the data to be used in public advisories regarding current air quality. In some cases, these data include
 statistical adjustments by the state/local monitoring agency based on one-time or ongoing correlation analysis with co-located FRM/FEM
 monitors, intended to improve the "FRM-likeness" of the continuous concentration data (e.g., Bortnick et al., 2002, 156285). State/local
 monitoring agency decisions about whether to adjust continuous PM2.5 data and whether their raw or adjusted continuous PM2.5 data
 should be associated with parameter code 88502 were informed by non-binding EPA guidance issued in 2006 (Technical Note on
 Reporting PM2 5 Continuous Monitoring and Speciation Data to AQS
 http://www.epa.gov/ttn/amtic/files/ambient/pm25/datamang/contrept.pdf).
December 2009                                      3-42

-------
    Concentration Range
    • >20.1 Lig/m3[l county]
      18.1 - 20.0 ng/m3 [1 counties]
      15.1 - 18.1 Lig/m3 [53 counties]
    • 12.1 - 15.0 Lig/m3 [242 counties]
    • < 12.0 ng/m3 [237 counties]
    n No data
Figure 3-9.    Three-yr avg 24-h PM2.s concentration by county derived from FRM or FRM-like
              data, 2005-2007.  The population bar shows the number of people residing within
              counties that reported county-wide average concentrations within the specified
              ranges.

      Table 3-8 contains summary statistics for PM2.5 reported to AQS for the period 2005-2007. All
24-h FRM and 1-h FRM-like data reported to AQS and meeting the completeness criterion outlined
above are included in the table. The table provides a distributional comparison between annual, 24-h
and 1-h averaging times, calendar years (2005, 2006 and 2007) and seasons: winter (December-
February), spring (March-May), summer (June-August), and fall (September-November). In
addition, 15 CSAs/CBSAs were chosen for their importance in recent PM health studies, as
described in Section 3.4, and have been included individually in the table.
      The distribution of PM2.5 annual averages (calculated  without seasonal weighting and
presented in Table 3-8) was generated from 2,382 individual annual means reported by 794 24-h
FRM monitors reporting to AQS between 2005 and 2007. The mean of the annual averages was
12 (ig/m3, equivalent to the mean of the individual 24-h avg. The maximum annual average PM2.5
concentration calculated from 24-h FRM data over these 3 yr was 23 (ig/m3 in Bakersfield, CA (AQS
monitor ID: 060290010) during 2007. This site is located in the heavily populated portion of the San
Joaquin Valley where air pollution frequently becomes trapped at ground level due to local
topography. The distribution of the 24-h and 1-h avg, both generated from the same 1-h FRM-like
data, are  comparable up to the 90th percentile. The 1-h avg is 3  (ig/m3 higher than the 24-h avg at the
95th percentile and 7 (ig/m3 higher at the 99th percentile. This deviation between  1-h and 24-h
averaging times is a result of short duration spikes in PM2.5 mass lasting long enough to influence the
upper percentiles of the 1-h distribution but not necessarily the 24-h avg distribution. Exceptional
events were not removed from this data set and are responsible for at least some of the higher
December 2009
3-43

-------
concentrations observed. For example, the maximum 1-h reading of 828 (ig/m3 was reported by a
monitor in Boise, ID (AQS monitor ID: 160010011) on July 4, 2007. Nine of the top 12 1-h PM2.5
concentrations reported across the country also occurred on July 4th, implicating fireworks as the
common source for these high values.
Table 3-8. PM2.6 distributions derived from AQS data (concentration in ug/m3).

n Meai

1
Percentiles
5
10
25
50
75
90
95
99


2005-2007 PM2.S FOR DIFFERENT AVERAGING PERIODS
Annual avga (24-h FRM)
24-h avg (24-h FRM)
24-havg(1-hFRM-like)
1-havg(1-hFRM-like)
2,382 12
349,028 12
183,057 10
4,403,817 10
5
2
1
0
7
4
2
1
8
4
3
2
10
7
5
4
12
10
8
8
14
16
13
13
16
23
19
21
17
28
24
27
19
39
35
42
23
193
126
828
PM2.5 ANNUAL AND SEASONAL STRATIFICATION USING 24-H AVG FRM DATA
2005
2006
2007
Winter (December-February)
Spring (March-May)
Summer (June-August)
Fall (September-November)
2005-2007 PM2.5 IN INDIVIDUAL
Atlanta
Birmingham
Boston
Chicago
Denver
Detroit
Houston
Los Angeles
New York
Philadelphia
Phoenix
Pittsburgh
Riverside
Seattle
St. Louis
AIMSCSAs/CBSAs
Notinthe15CSAs/CBSAs
114,346 13
113,197 12
121,485 12
86,286 12
88,489 11
86,830 14
87,423 12
2
2
2
2
2
2
2
4
4
4
4
3
4
3
5
4
4
5
4
5
4
7
7
7
7
6
8
6
11
10
10
10
9
12
10
17
15
16
15
14
19
15
24
21
22
22
20
26
22
30
26
27
27
24
31
26
42
36
40
44
33
40
39
133
193
145
193
145
133
126
CSAS/CBSAS USING 24-H AVG FRM DATA
4,939 15
4,869 16
8,464 10
10,308 14
4,192 9
5,223 14
1,342 15
6,600 15
15,826 13
7,541 14
1,634 10
5,783 16
2,751 17
1,297 9
6,887 14
87,656 14
261,372 12
4
4
2
3
2
2
4
3
2
3
2
3
3
2
3
2
2
6
6
3
4
3
3
6
5
4
4
3
5
5
3
5
4
3
7
7
4
6
4
5
8
6
4
5
4
6
6
3
6
5
4
10
10
5
8
6
7
10
9
6
8
6
9
10
4
9
7
6
14
15
9
13
8
12
14
13
10
12
9
13
14
7
13
12
10
19
21
13
18
10
19
18
18
17
18
12
20
21
10
18
17
15
25
29
20
25
14
26
23
25
24
25
17
29
31
20
24
25
22
29
34
24
31
18
31
26
32
29
30
21
36
40
29
29
30
27
37
47
32
42
31
45
34
50
39
38
32
52
58
43
40
42
38
145
64
50
65
61
82
44
133
58
63
77
101
106
68
50
145
193
3Straight annual average without quarterly weighting.
December 2009
3-44

-------
      The distribution of the 24-h FRM PM2.5 data was similar across the 3 years (2005-2007)
investigated. Summer (June-August) had the highest mean and median relative to other seasons, but
only by a small margin. For the 99th percentile, winter (December-February) was slightly higher
than the other seasons. This is consistent with wintertime stagnation events resulting in short-term
elevated PM2.5 concentrations.  Of the 15 CS As/CBS As investigated, the highest mean of 24-h PM2.5
concentrations was reported for Riverside (17  (ig/m3), Birmingham (16 (ig/m3) and Pittsburgh
(16 (ig/m3); the lowest was reported for Denver (9 (ig/m3) and Seattle (9 (ig/m ).

      PMlO-2.5
      Since PMi0_2.5 is not routinely measured and reported to AQS, co-located PMi0 and PM2.5
measurements from the AQS network were used to investigate the spatial distribution in PMi0_2.5.
Only low-volume FRM or FRM-like samplers were considered in calculating PMi0_2.5 to avoid
complications with vastly different  sampling protocols (e.g., flow rates) between the independent
PMio and PM2.5 measurements. The same 11+ days per quarter completeness criterion discussed
above was applied to the PM10 and  PM2.5 measurements. The PM2 5 concentrations are reported to
AQS at local conditions whereas the PMi0 concentrations are reported at standard conditions.
Therefore, prior to calculating PMi0_2.5 by subtraction, the PMi0 AQS data were adjusted to local
conditions on a daily basis using temperature and pressure measurements from the nearest National
Weather Service station. Figure 3-10 shows the 3-yr mean of the 24-h PMi0_2.5 concentration by
county across the U.S. for 2005-2007. There is considerably less coverage for PMi0_2.5 than for PM25
or PM10 alone since only a small subset of PM monitors are co-located and low-volume. The 40
counties included in Figure 3-10 incorporate less than 5% of the U.S.  population. Of the 3,225 U.S.
counties, only 40 (1%) met the completeness and co-location criteria in all 3 yr (2005-2007), and
therefore the available measurements do not provide sufficient information to adequately
characterize regional-scale coarse PM spatial concentration distributions.
      Table 3-9 contains summary statistics for PMi0_2.5 for the period 2005-2007 similar to those
reported in Table 3-8 for PM25. Only six of the 15 CS As/CBS As had sufficient data for inclusion in
Table 3-9. Although fewer monitoring sites within these CSAs/CBSAs were used for PMi0_2.5 than
for PM25, Table 3-8 and Table 3-9 provide a rough comparison of the PM present in the fine and
thoracic coarse modes for these six  cities. The eastern cities including Atlanta, Boston, Chicago and
New York all had a higher fraction in the fine mode with the greatest ratio of fine to thoracic coarse
in Chicago (14 (ig/m3 PM25 5 (ig/m3 PMi0_2s ratio = 2.8). In contrast, Denver (9 (ig/m3 PM25,
20 (ig/myPM10_25, ratio = 0.45) and Phoenix (10 (ig/m3 PM25, 22 (ig/m3 PM10_25, ratio = 0.45) had a
higher fraction in the thoracic coarse mode. Given the limited information available from AQS for
PMio_2.5 and the current NAAQS for PMio, the next  section characterizes the more prevalent
data, acknowledging that PMio incorporates both thoracic coarse and fine particles.
December 2009                                  3-45

-------
     Concentration Range
       > 26 \igltt? [1 county]
     * 21 - 25 \ig/K? [3 counties]
       16 - 20 |Jg/m3 [3 counties]
       11 - 15^g/m3[17 counties]
     " < 10 Lig/m3 [16 counties]
     D No data
Figure 3-10.   Three-yr avg 24-h PM10.2.s concentration by county derived from co-located low
              volume FRM PM10 and PM2.6 monitors, 2005-2007. The population bar shows the
              number of people residing within counties that reported county-wide average
              concentrations within the specified ranges.
December 2009
3-46

-------
Table 3-9.    PMi0.2.6 distributions derived from AQS data (concentration in ug/m3).

n
IV

1
Percentiles
5 10
25
50
75
90
95
99
— Max

2005-2007 PM10-2.s FOR DIFFERENT AVERAGING PERIODS
Annual avga (low volume FRM)
24-h avg (low volume FRM)
130
12,027
12
13
PM10-2.s ANNUAL AND SEASONAL STRATIFICATION USING
2005
2006
2007
Winter (December-February)
Spring (March-May)
Summer (June-August)
Fall (September-November)
3,990
4,037
4,000
2,942
3,088
2,968
3,029
12
13
13
11
13
14
14
3
-3
5 6
1 2
9
6
11
10
14
17
19
26
23
33
39
54
43
246
24-H AVG LOW VOLUME FRM DATA
-5
-2
-2
-5
-2
-2
-2
0 2
1 2
1 3
-1 1
1 2
3 5
1 3
5
6
6
4
5
8
6
10
10
11
8
10
12
11
16
17
18
15
17
18
18
26
27
26
27
26
25
28
33
34
33
34
33
31
34
52
56
56
56
62
44
60
246
182
148
246
151
93
148
2005-2007 PM10-2.s IN INDIVIDUAL CSAS/CBSAS USING 24-H AVG LOW VOLUME FRM DATA"
Atlanta
Boston
Chicago
Denver
New York
Phoenix
All 6 CSAs/CBSAs
Not in the 6 CSAs/CBSAs
167
340
161
353
338
163
1,522
10,505
10
7
5
20
9
22
12
13
-4
-2
-8
0
-16
-3
-6
-2
1 2
1 2
-4 -3
4 6
-2 1
8 11
0 2
1 2
5
4
1
11
5
16
5
6
9
6
4
19
8
20
10
10
13
9
8
28
12
29
17
17
18
12
14
36
17
35
27
26
21
16
19
42
23
46
34
33
30
25
37
59
34
67
51
56
46
27
37
78
56
70
78
246
3Straight annual average without quarterly weighting.
bNo co-located low-volume FRM PM10and FRM-like PM25 monitors available for Birmingham, Detroit, Houston, Los Angeles, Philadelphia, Pittsburgh, Riverside, Seattle or St. I
      PM10

      Figure 3-11 shows the 3-yr mean of the 24-h PMi0 concentrations by county across the U.S.
for 2005-2007. Both FRM and FEM PMi0 data reported to AQS were included and the same
11+ days per quarter completeness criterion described above for PM2.5 was applied. The highest
3-yr avg for PMi0 (>50 (ig/m3) occurred in inland southern California and the populous counties of
southern Arizona and central New Mexico. Of the 3,225 U.S. counties, 676 (12%) contained PM10
data meeting the completeness criterion in all three years; these 676 counties incorporate
approximately 43% of the U.S. population.
December 2009
3-47

-------
    Concentration Range
    • > 51 \ig/m3 [1 counties]
    "41-50 ^g/m3 [15 counties]
      31-40 \ig/m3 [378 counties]
    • 21 - 30 >ig/m3[ 162 counties]
    *  < 20 \ig/m3 [114 counties]

    n No data
Figure 3-11.   Three-yr avg 24-h PM10 concentration by county derived from FRM or FEM
              monitors, 2005-2007.  The population bar shows the number of people residing
              within counties that reported county-wide average concentrations within the
              specified ranges.

      Table 3-10 contains summary statistics for PMi0 reported to AQS for the period 2005-2007.
Both 24-h FRM and 1-h FEM data are included in the table. To facilitate a distributional comparison
between averaging times, annual, 24-h and 1-h averaging times using the FRM and FEM data have
been included separately in Table 3-10. As in the earlier tables, the data is also stratified by year and
season and includes the 15 CSAs/CBSAs individually.
December 2009
3-48

-------
Table 3-10. PMio distributions derived from AQS data (concentration in

n
Mea

1
ug/m3).
Percentiles
5 10
25
50
75
90
95
99


2005-2007 PM10 FOR DIFFERENT AVERAGING PERIODS
Annual avga (24-h FRM and 1-h FEM)
24-havg(24-hFRMand1-hFEM)
24-h avg (24-h FRM)
24-h avg (1-h FEM)
1-h avg (1-h FEM)
2022
326,675
167,310
156,931
3,767,533
25
26
25
26
27
10
3
2
4
1
14 16
6 9
6 9
7 9
4 6
19
14
14
14
11
23
21
21
21
19
28
32
31
32
32
35
46
45
48
51
44
59
57
62
69
60
97
91
105
145
85
8299
8299
979
8540
PM10 ANNUAL AND SEASONAL STRATIFICATION USING 24-H AVG FRM AND FEM DATA
2005
2006
2007
Winter (December-February)
Spring (March-May)
Summer (June-August)
Fall (September-November)
2005-2007 PM10 IN INDIVIDUAL
Atlanta
Birmingham
Boston
Chicago
Denver
Detroit
Houston
Los Angeles
New York
Philadelphia
Phoenix
Pittsburgh
Riverside
Seattle
St. Louis
AIMSCSAs/CBSAs
Notinthe15CSAs/CBSAs
107,524
109,505
109,646
80,959
82,772
81,351
81,593
25
26
26
23
25
29
26
2
3
4
2
2
6
3
6 9
6 9
7 9
5 7
6 8
10 12
7 9
13
13
14
11
13
18
14
21
21
21
17
20
25
21
31
32
32
27
31
35
32
46
46
47
42
45
49
48
58
59
60
57
58
60
62
93
101
99
99
96
92
102
1441
8299
2253
8299
2253
1839
1212
CSAS/CBSAS USING 24-H AVG FRM AND FEM DATA
1,868
5,478
1,412
6,165
4,706
1,407
1,397
2,020
514
4,207
12,005
12,677
4,327
2,136
2,464
62,783
263,892
24
34
17
26
28
30
31
27
19
19
52
24
35
19
33
32
24
6
6
2
6
5
7
7
4
2
4
7
4
4
5
6
5
2
9 11
9 12
5 7
9 11
10 12
10 12
10 12
8 11
6 7
7 9
14 19
7 9
8 11
7 9
10 12
8 10
6 8
16
19
10
16
18
18
17
18
11
12
29
13
19
12
18
16
13
23
28
15
23
25
26
23
25
17
17
44
19
30
17
28
25
20
31
43
22
32
35
38
34
33
25
24
65
31
45
23
42
39
30
39
64
30
45
47
53
56
42
35
34
91
45
64
31
59
60
43
44
82
36
55
54
64
80
51
40
40
112
57
75
37
74
77
54
57
120
50
78
75
81
137
74
51
52
166
83
111
52
114
120
88
108
241
58
214
118
182
248
489
83
84
2253
157
1212
79
315
2253
8299
3Straight annual average without quarterly weighting
December 2009
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      The maximum annual average PM10 concentration calculated from 24-h FRM data over these
three years was 85 (ig/m3 in Stanfield, AZ (AQS monitor ID: 040213008) during 2007. Stanfield is a
small agricultural town (2007 population = 1074) approximately 64 km south of Phoenix and is in a
region heavily influenced by windblown dust. Many of the maximum 24-h and 1-h avg PMi0
concentrations in Table 3-10 exceed 1,000 (ig/m3, but these represent rare events given the much
lower 99th percentiles. Exceptional events were not removed from this data set and are responsible
for at least some of the higher concentrations observed.
      The distribution of the 24-h FRM and FEM PMi0 data was similar across the three years
(2005-2007) investigated. Summer (June-August) had the highest mean and median relative to other
seasons, consistent with PM2.5 observations. Of the 15 CSAs/CBSAs investigated, the highest mean
of 24-h PMio concentrations was reported for Phoenix (52 (ig/m3), considerably higher than the
means for the other CSAs/CBSAs investigated. The lowest was reported for Boston (17  (ig/m3) with
New York, Philadelphia and Seattle only slightly higher (19 (ig/m ).
      On average using the 2005-2007 data for PM2.5 in Table  3-8 and PMi0 in Table 3-10, the
distribution between fine and coarse PM varies substantially by location. A larger fraction of PM
mass is present in the thoracic coarse mode in Phoenix and Denver (3-yr mean PM2.5/PMi0 ratios of
0.19 and 0.32, respectively). In contrast, a larger fraction is present in the fine  mode in Philadelphia
(0.74), New York (0.68) and Pittsburgh (0.67). Comparisons of PM2.5 to PMi0  as reported to AQS
should be used with caution, however, since PM2 5 concentrations are reported for local conditions
while PMio concentrations are converted to STP before reporting. Nevertheless, these findings are
consistent with those in Table 3-9 for PMi0_2.5 in the subset of 6 cities with available co-located low-
volume PM data that have been properly adjusted for temperature and pressure. These findings are
also consistent with those reported in the 2004 PM AQCD (U.S. EPA, 2004, 056905) where ratios of
PM2 5 to PMio were observed to be highest in the northeast (0.70), southeast (0.70), and industrial
Midwest (0.70) and lower in the upper Midwest (0.53), northwest (0.50), southern California (0.47)
and southwest (0.38).

      UFPs

      Little is known about the spatiotemporal distribution or composition of UFPs  on a regional
scale. New particle formation has been observed in environments ranging from relatively unpolluted
marine and continental environments to polluted urban areas as an ongoing background  process and
during nucleation events (Kulmala et al, 2004, 089159). During nucleation events, which may last
for several hours, UFP number concentrations can exceed  104 per cm3 over distances of several
hundred kilometers (Kulmala et al., 2004, 089159; Qian et al.,  2007, 116435).  These events occur
throughout the year on 5-40% of days, depending on location (Qian et al., 2007, 116435). Cloud
condensation nuclei, with diameters between ~10 and -100 nm have been monitored for several
years  at a number of nonurban sites in the U.S. (http://cmdl.noaa.gov/aero/data/). Average particle
number counts at these sites in the U.S. range from several hundred to several  thousand per cm3. The
particles are formed by nucleation of atmospheric gases with additional contribution from primary
emissions  in these environments (Pierce and Adams,  2009, 191189).
      In an urban setting, a large percentage of UFPs  come from combustion-related emissions from
mobile sources (Sioutas et al., 2005, 088428). UFP number concentrations drop off quickly with
distance from the roadway  (Levy et al., 2003, 052661; Reponen et al., 2003, 088425; Zhu et  al.,
2005, 157191). and therefore concentrations can be highly heterogeneous in the near-road
environment depending on traffic, meteorological and topographic conditions (Baldauf et al., 2008,
190239). Studies characterizing spatial variability in UFPs are  currently limited to a handful  of close
proximity  locations and therefore are discussed in Sections 3.5.1.2 and 3.5.1.3 in the context of
urban- and neighborhood-scale variability. Further elaboration on the composition of UFPs is
included below.

      PM Constituents

      Only PM25 is collected routinely at CSN network sites so the majority of this  section on PM
constituents is devoted to PM2 5 composition. PM10_2.5 and  UFP composition is discussed to the
extent possible below. Figure 3-12 through Figure 3-16 contain U.S. concentration maps for OC, EC,
SO42~, NO3", and NH4+ mass from PM2 5 measurements taken as part of the CSN network for the
period 2005-2007. Data used in these figures are as reported to AQS: no correction was applied to
OC for non-carbon mass and NO3" represents total particulate nitrate. Figure 3-12 shows regions of
December 2009                                 3-50

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high PM2.5 OC mass concentration with annual average concentrations greater than 5 (ig/m3 in the
western and the southeastern U.S. Concentrations at the western monitors peak in the fall and winter
while those in the Southeast peak anywhere from spring through fall. The central and northeastern
portions of the U.S. generally contain lower measured OC. Bell et al. (2007, 155683) present a
similar map for estimated organic carbon mass (OCM) from 2000-2005 calculated by multiplying
the blank corrected OC measurement by 1.4 to account for non-carbon mass. There are a range of
estimates in the literature for suggested scaling factors (Turpin and Lim,  2001, 017093). depending
predominantly on how highly oxygenated the aerosol is (Pang et al., 2006, 156012). Fresh PM, more
common in urban regions, has undergone limited chemical transformation. As the aerosol is
transported to rural regions, it becomes more oxygenated. Turpin and Lim (2001, 017093)
recommended ratios of 1.6 ± 0.2 for urban and 2.1 ± 0.2 for non-urban aerosols. Estimates range
from 1.6 to 2.6 for rural IMPROVE monitors (El-Zanan et al., 2005, 155764). Therefore, applying
one correction factor of 1.4 across the entire U.S. will lead to an underestimate of the OCM in rural
regions. Therefore, the OC data in Figure 3-12 is presented as measured with a national blank
correction, but no adjustment to OCM.
      Figure 3-13 contains a similar map for PM2.5 EC mass concentration that exhibits smaller
seasonal variability than OC, particularly in the eastern half of the U.S. There are isolated monitors
spread throughout the country that measure high  annual average EC concentrations. These EC 'hot
spots' are primarily associated with larger metropolitan areas such as Los Angeles, Pittsburgh, and
New York, but El Paso, TX, also reported high annual average EC concentrations (driven by a
wintertime average concentration greater than 2 (ig/m3). In a similar analysis for EC by Bell et al.
(2007, 155683) for 2000-2005 data, there were also high wintertime EC concentrations in eastern
Kentucky  and western Montana. These particular locations do not stand out in the 2005-2007 data  in
Figure 3-13.
      Figure 3-14 contains a map for PM2.5 SO42~ mass concentration which shows that SO42~ is
more prevalent in the eastern U.S. owing to the strong west-to-east gradient in SO2 emissions. This
gradient is magnified in the summer months when more sunlight is  available for photochemical
formation of SO42~. In contrast, PM2 5 NO3~ mass concentration in Figure  3-15 is highest in the west,
particularly in California. There are also elevated concentrations of NO3~ in the upper Midwest. The
seasonal plots show generally higher NO3~ in the wintertime as a result of temperature driven
partitioning. Exceptions exist in Los Angeles and Riverside where high NO3~ readings appear year-
round. The PM25 NH4+ mass concentration maps in Figure 3-16 shows spatial patterns related to
both SO42~ and NOjT resulting from its presence in both (NH4)2SO4  and NH4NO3. Figure A-31
through Figure A-36 in Annex A show similar U.S. concentration maps for PM25 Cu, Fe, Ni, Pb, Se
and V mass concentrations as measured by XRF.  There is considerably less seasonal variation in the
concentration profile for these metals than OC or the ions.
      For the 15 metropolitan areas identified earlier, the  contribution of the major component
classes to total PM2 5 mass was  derived using the measured sulfate,  adjusted NO3~, derived water,
inferred carbonaceous mass approach (SANDWICH) (Frank, 2006, 098909). This approach uses the
measured  FRM PM2 5 mass and co-located CSN  chemical constituents to  perform a mass balance-
based estimation of the PM25 mass fraction attributed to SO42~, NO3~, EC, OCM, and crustal
material. SO42~ and NO3~ include associated NH4+ mass and estimated particle-bound water.
Furthermore, NO3~ is assumed to be fully neutralized as NH4NO3 and has been adjusted to represent
the amount retained by the FRM monitor. EC is taken as measured,  and the crustal component is
derived from common oxides contained in the Earth's crust (Pettijohn, 1957, 156862). but can also
include significant anthropogenic contributions, such as coal fly ash that are unrelated to soil
resuspension. Finally, OCM is estimated using mass balance by subtracting the sum of all other
constituents from the FRM PM2 5 mass. The SANDWICH method takes into account passive
collection of semi-volatile or handling-related mass on the FRM filters in the mass balance
calculation. The magnitude of this artifact is assigned a nominal value of 0.5 (ig/m3, which is derived
from limited analysis of FRM field blanks. Other constituents such  as salt and other metallic oxides,
however, are not included in these calculations and therefore the OCM fraction estimated by mass
balance represents an upper bound on the FRM retained OCM. The calculations and assumptions
that go into the SANDWICH method are discussed in detail in Frank (2006, 098909)with further
information available on EPA's AirExplorer web  site
http://www.epa.gov/cgi-bin/htmSOL/mxplorer/query  spe.hsql
December 2009                                 3-51

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                                          oc
                                        Annual
                                                tX^v^S

                                                Off)
                                                            «.o
                                               o
      Concentration (ng/m3):  <1.25    >1.25-2.5C    >2.50 -3.75   >3.75-5.jO   >5.00

                    Spring                                    Summer
                    Fall
                    Winter
Figure 3-12.   Three-yr avg 24-h PM2s OC concentrations measured at CSN sites across the
              U.S., 2005-2007.
December 2009
3-52

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                                          EC
                                        Annual

     Concentration (ng/m3): <0.5


                    Spring
                                             •         •        •
                              >0.5-1.G    M.0-1.5    >1.5-2.0    >2.0
                   Summer
                                                                 . •. "s° ^'^j.0
                                                         ••      ''   ,-&
                                                               .
                    Fall
                    Winter
    •  ,*
Figure 3-13.   Three-yr avg 24-h PM2s EC concentrations measured at CSN sites across the
             U.S., 2005-2007.
December 2009
3-53

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                                         so/
                                        Annual

       Concentration (ng/m3):  <2
                                  *
                                >2-4
   c
 >4-6
>B
                    Spring
                   Summer
                    Fall
                    Winter
Figure 3-14.   Three-yr avg 24-h PM2s S042~ concentrations measured at CSN sites across the
             U.S., 2005-2007.
December 2009
3-54

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                                          N03-
                                        Annual
      Concentration (ng/m3):  <1

                    Spring
                    Fall
 >2-3       >3-4       >4

                   Summer
                    Winter
Figure 3-15.   Three-yr avg 24-h PM2.s N0s~ concentrations measured at CSN sites across the
             U.S., 2005-2007.
December 2009
3-55

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                                          NH4+
                                         Annual

       Concentration (ng/m3): <1

                    Spring
 >2-3   .    X3-4        >4

                    Summer
                    Fall
                    Winter
                                                            *.  .
Figure 3-16.   Three-yr avg 24-h PM2.s NH4+ concentrations measured at CSN sites across the
              U.S., 2005-2007.
December 2009
3-56

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      Figure 3-17 shows the PM2.5 compositional breakdown for the 15 CSAs/CBSAs. All available
monitoring sites with co-located FRM PM2.5 and CSN speciation data reporting in all four seasons
for at least one calendar year from 2005-2007 were included. Furthermore, each season was required
to contain five reported values for mass and the major PM2.5 constituents. This resulted in a varying
number of sites (ranging from one to seven, as indicated in the caption to Figure 3-17) used to create
the averages shown in the figure. Variability in PM2.5 composition within each CSA/CBSA where
multiple monitors were available and trends in composition over time are discussed in subsequent
sections.
        Sulfate  f
        Nitrate
        EC
        OCM
        Crustal
Figure 3-17.   Three-yr avg PM2.s speciation estimates for 2005-2007 derived using the
              SANDWICH method. For the following 15 CSAs/CBSAs (with the number of sites
              per CSA/CBSA listed in parenthesis): Atlanta, GA (1); Birmingham, AL (3);
              Boston, MA (4); Chicago, IL (7); Denver, CO (2); Detroit, Ml (4); Houston, TX (1);
              Los Angeles, CA (1); New York City, NY (7); Philadelphia, PA (6); Phoenix, AZ (2);
              Pittsburgh, PA (4); Riverside, CA (1); Seattle, WA (4); and St. Louis, MO (3). S04*~
              and N0s~ estimates  include NH4+ and particle bound water and the circle area is
              scaled in proportion to FRM PM2.s mass as indicated in the legend.

      On an annual average basis, SO42~ is a dominant PM component in the eastern U.S. cities. For
the presented cities, this includes everything east of Houston where the SO42~ fraction of PM25
ranges from 42% in Chicago to 56% in Pittsburgh on an annual average basis. OCM is the next
largest component in the east ranging from 27% in Pittsburgh to 42% in Birmingham. In the west,
OCM is the largest constituent on an annual basis, ranging from 34% in Los Angeles to 58% in
Seattle. SO42~, NO3~ and crustal material are also important in  many of the included western cities. In
the west, fractional SO42~ ranges from 18% in Denver to 32% in Los Angeles while fractional NO3~
is relatively large in Riverside (22%), Los Angeles (19%) and  Denver (15%) and less important on
an annual basis in Phoenix (1%) and Seattle (2%). Crustal material is particularly prevalent in
Phoenix (28%). EC makes up a smaller fraction of the PM25 (4-11%), but it is consistently present in
all included cities regardless of region.
December 2009
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                      Spring
               Summer
Figure 3-18.   Seasonally-stratified 3-yr avg PM2 5 speciation estimates for 2005-2007 derived
              using the SANDWICH method. For the following 15 CSAs/CBSAs: Atlanta, GA;
              Birmingham, AL; Boston, MA; Chicago, IL; Denver, CO; Detroit, Ml; Houston, TX;
              Los Angeles, CA; New York City, NY; Philadelphia, PA; Phoenix, AZ; Pittsburgh,
              PA; Riverside, CA; Seattle, WA; and St. Louis, MO. S042" and N03~ estimates
              include NH4+ and particle bound water and the circle area is scaled in proportion
              to FRM PM2.s mass as indicated in the legend.

      The seasonal variation in PM2.5 composition across the 15 CSAs/CBSAs is shown in Figure
3-18 where the seasons are defined as before. SO42~ dominates in most metropolitan areas  in the
summertime, while NO3~ becomes important in the colder wintertime months. Notable exceptions
include Denver, Phoenix, Riverside, and Seattle where summertime SO42~ makes up a smaller
fraction of the PM2.5 mass compared with other regions. Likewise, NO3~ is less pronounced in the
wintertime in Atlanta, Birmingham, Houston, Phoenix, and Seattle compared with other regions. Los
Angeles and Riverside exhibit elevated NO3~ from fall through spring. Crustal material is a
substantial summertime component in Houston (26%), and is generally low elsewhere in the East in
all seasons. In the West, crustal material represents a substantial component year-round in  Phoenix
and Denver.
      The only PM size fraction routinely collected at CSN network sites is PM25, resulting in less
available information on speciated PM10_2.5. Edgerton et al.  (2005, 088686; 2009, 180385)  published
speciated measurements for PM2 5 and PMi0_2.5 obtained using dichotomous samplers from four
locations included in the Southeastern Aerosol Research and Characterization (SEARCH)  study:
Yorkville, GA, Centreville, AL, Birmingham, AL and Atlanta, GA. Samples were collected between
1999 and 2003 on  a l-in-3 day or l-in-6 day schedule, depending on site. Speciated measurements
for both PM25 and PMi0_2.5 included SO42~, NO3", NH4+, and major metal oxides (MMO). In addition,
OC and either black carbon (BC) or EC were reported for PM2 5 over the entire study period and for
PMio_2.5 for a subset of samples extending from April 2003 to April 2004.
      For the Atlanta and Birmingham SEARCH sites, the annual average NO3" mass fraction was
approximately equal for PM25 (5.6% and 5.0%, respectively, for Atlanta and Birmingham) and PMi0_
2.5 (4.9% and 3.3%). Likewise, the OC mass fraction was approximately equal for PM25 (26% and
 5%) and PMi0_25 (24% and 27%). MMO contributed an order of magnitude smaller mass fraction to
PM2.5 (2.6% and 4.7%) than PM10_2.5 (38% and 35%). In contrast, SO?" contributed an order of
December 2009
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magnitude greater mass fraction to PM25 (25.1% and 24.1%) than PM10_25 (2.8 and 2.1%). BC also
contributed a larger mass fraction of PM2.5 (8.6% and 10.5%) than EC did for PMi0.2.5 (2.9% and
2.4%). Based on these findings, MMO are present primarily in the thoracic coarse mode, while SO42~
and EC/BC are present primarily in the fine mode. NO3~ and OC are present in both modes in
approximately equal mass fractions. These results are specific to Atlanta and Birmingham and may
not represent other geographic regions.
      Information about the composition of ambient UFPs directly emitted by sources is still sparse
compared to that for the larger size modes. However, their composition is expected to reflect that of
their sources. As noted in Section 3.3 (and references therein), particle number emissions from motor
vehicles are dominantly in the UF size range. The composition of gasoline vehicle emissions consists
mainly of a mix of OC, EC and small quantities of trace metals and sulfates, with OC constituting
anywhere from 26-88% of PM. Diesel PM is generally comprised of an  EC and trace metal ash core
onto which organic material and nucleation-mode SO42~condense. With the introduction of new
diesel emissions standards in 2007, total emissions have decreased dramatically, particularly for
carbon. In areas where atmospheric nucleation is the dominant source of UFPs, sulfate along with
ammonium, and secondary organic compounds are the likely major components of UFPs.
      In a study conducted at several urban sites in Southern California, Cass et al. (2000 020680)
found that the composition of UFPs ranged from 32-67% OC, 3.5-17.5% EC, 1-18% SO4 , 0-19%
NO3~, 0-9% NH4+, 1-26% metal oxides, 0-2% Na, and 0-2% Cl.  Thus carbon, in various forms, was
found to be the major contributor to the mass of UFPs.  However, ammonium was found to contribute
33% of the mass of UFPs at one site in Riverside. Fe was the most abundant metal found in the
UFPs. Chung et al. (2001, 017105) found that carbon was the major component of the mass of UFPs
in a study conducted during January of 1999 in Bakersfield, CA. However,  in the study of Chung et
al. (2001, 017105). the contribution of carbonaceous species (OC and EC; typically 20-30%) was
much lower than that found in the cities in Southern California. They found that Ca was the
dominant cation, accounting for about 20% of the mass of UFPs in their samples. Sizable
contributions from Si (0-4%) and Al (6-14%) were also found. MOUDIs are used to collect size-
segregated filter samples in the UFP compositional analyses described above. Coarse particle bounce
is a concern when using MOUDIs and further studies, including scanning electron microscopy, may
be needed to quantify the effect of this sampling artifact on UFP compositional analyses.
      Herner et al. (2005, 135983) reported a gradual increase in OC mass fraction as particle size
decreases from 1 (im (20% OC) to 100 nm (80% OC) in the San Joaquin Valley of California.  Sardar
et al. (2005, 180086) found OC to be the major component of UFPs at four locations in California,
with higher OC mass fraction in the wintertime relative to summertime.  EC and SO42~ were also
present in the UFP samples, but at much smaller mass fractions.  EC was present year-round,
whereas SO42~had a summertime increase. More detailed chemical  characterization of the OC
fraction of ambient UFPs is extremely limited, but recent studies have identified specific organic
molecular markers affiliated with motor vehicle emissions including hopanes  and PAHs (Fine et al.,
2004, 141283; Ning et al., 2007, 156809; Phuleria et al., 2007, 117816).
      As noted in the 2004 PM AQCD (U.S. EPA, 2004,  056905). primary  biological aerosol
particles (PBAP), which include microorganisms, fragments of living things, and organic compounds
of miscellaneous origin in surface deposits on filters, are not distinguishable in analyses of total OC.
A clear distinction should be made between PBAP and primary OC  that  is produced by organisms
(e.g., waxes coating the surfaces of organisms)  and precursors to secondary OC such as isoprene and
terpenes.  Indeed, the fields of view of many photomicrographs of PM samples obtained by scanning
electron microscopy are often dominated by large numbers of pollen spores, plant and insect
fragments, and microorganisms. Bioaerosols such as pollen, fungal  spores, and most bacteria are
expected to be found mainly in the coarse size fraction (see Figure 3-2 for an illustrative example of
a pollen particle). However, allergens from pollens can also be found in  respirable particles
(Edgerton et al., 2009, 180385; Taylor, 2002, 025693).  Matthias-Maser et al. (2000, 155972)
summarized information about the size distribution of PBAP in and around Mainz, Germany in what
is perhaps the most complete study of this sort.  Matthias-Maser found that PBAP constituted up to
30% of total particle number and volume in the approximate size range from 0.35-50 (im on an
annual basis. Additionally, whereas the contribution of PBAP to  the total aerosol volume did not
change appreciably with season, the contribution of PBAP to total particle number ranged from
about 10% in December and March to about 25% in June and October. Bauer et al. (2008, 189986)
measured contributions of fungal spores to OC  at an urban and a suburban site in Vienna, Austria in
spring and summer. Fungal spores at the suburban site contributed on average 10% to OC in PMi0
December 2009                                 3-59

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and 5% at the urban site. At the suburban site, in summer, fungal spores accounted on average for
60% of the OC (0.56 (ig/m3) in PMi0_2.i (2.6 (ig/m3). The contribution to PM2.i was estimated to be
about 10% that in PMi0_21. Womiloju et al. (2003, 179954) estimated that fungal spores contribute
14-22% of OC in PM2 5 in and around Toronto.
      Edgerton et al. (2009, 180385) found that PBAP contributed 60-70% of OC (average
~1.7 (ig/m3) in PMi0_2.5 at an urban and a rural site in Alabama in fall of 2000 and spring of 2001.
The percentage contributions were similar at both sites and higher concentrations were found in
spring than in fall. Although results for the U.S. are more limited, they are broadly consistent with
the results of the other studies in illustrating the importance of PBAP, at least for fungal spores in
OC.


3.5.1.2.   Urban-Scale Variability


      PM2.5

      Data from the 15 CSAs/CBSAs were used to investigate urban-scale variability in PM
reported to AQS. PM2.5 has a longer residence time in the atmosphere compared to PMi0_2.5 resulting
from a slower Vd. As a result, PM2.5 exhibits increased spatial homogeneity with relatively less
localized influence from point sources. Maps of PM2.5 monitor locations and box plots of seasonal
PM2.5 mass concentration data are provided for Boston (Figure 3-19 and Figure 3-20), Pittsburgh
(Figure 3-21 and Figure 3-22), and Los Angeles (Figure 3-23 and Figure 3-24). Figures A-37 through
A-80 in Annex A contain similar information for all 15 CSAs/CBSAs under investigation. With very
few exceptions, the PM2 5 concentration is quite uniformly distributed across the monitors. Los
Angeles has one monitor (Site I) that reported noticeably less PM2 5 in all four seasons than the rest
of the monitors in the region. This monitor is located at Lancaster CA, separated from the rest of the
Los Angeles region by the San Gabriel Mountains. In general, however, PM2 5 varies approximately
the same magnitude between monitors as it does between seasons for the 15 selected cities.
      Table 3-11 through Table 3-13 contain pair-wise monitor site comparison statistics for PM25 in
Boston, Pittsburgh, and Los Angeles, respectively. Tables A-20 through A-34 in Annex A contain the
same statistics for PM25 measured within all 15 of the CSAs/CBSAs investigated. Comparison
statistics  shown include the Pearson correlation coefficient (R), the 90th percentile of the absolute
difference in concentrations (P90), the coefficient of divergence (COD) and the number of paired
observations (n). The COD provides an indication of the variability across the monitoring sites in
each CSA/CBSA and is defined as follows:
                                                                                   Equation 3-2

where X^ and X& represent observed concentrations averaged over some measurement averaging
period i (hourly, daily, etc.) at sites j and k, and/? is the number of paired observations. A COD of 0
indicates there are no differences between concentrations at paired sites (spatial homogeneity), while
a COD approaching 1 indicates extreme spatial heterogeneity.
      Temporal correlations between 24-h PM25 concentrations in Boston range from 0.61 to 0.97 in
Table 3-11. The lowest correlation in this CSA was between Site A located in Fall River, MA, 1 km
from the Narragansett Bay and Site L located in Nashua, NH, on the bank of the Merrimack River,
120 km north. The highest correlation was between Sites P and R, located less than a kilometer apart
in Providence, RI.
      In Pittsburgh, 24-h PM25 correlations range from 0.65 to 0.97. The lowest correlation in this
CSA was between Sites B and D, located diametrically opposite downtown Pittsburgh and 33 km
apart. The highest correlation was for Sites K and D, located 21 km apart and both west of
downtown. The prevailing wind in Pittsburgh is from the west, which explains  the higher correlation
between the two upwind sites.
      In Los Angeles, 24-h PM25 correlations range from 0.21 to 0.96. The lowest correlation was
between Sites I and J located 123 km apart and separated by the San Gabriel Mountains as discussed
December 2009                                 3-60

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earlier. The highest correlation was for sites G and H, located 3.7 km apart and both in Long Beach,
CA. Therefore, while distance between monitors plays an important role in how well any two
monitors correlate, other factors such as meteorology and topography can be important as well.
                      Boston Combined Statistical Area
           Ql
              r
                      Boston CSA
                   •  PMa.s Monitors
                   	 Interstate Highways
                    — Major Highways
                                           0 10 20
           40
60
80
 100
zzi Kilometers
Figure 3-19.   Locations of PM2.s monitors and major highways, Boston, MA.
December 2009
3-61

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ABCDEFGH J
Mean 9.1 9.1 8.9 9.4 9.6 11.7 11.6 10.5 12.1 10.7
Obs 341 350 342 355 357 349 398 349 1015 335
SD 6.0 6.5 6.3 6.6 6.6 7.0 6.8 6.9 6.9 7.2
40 -
AQSStelD
Site A 25-005-1004
SiteB 25-009-2006
SiteC 25-009-5005 .„
—. 30 -
SiteD 25-009-6001 ^
SiteE 25-023-0004 'g,
SiteF 25-025-0002 —
SiteG 25-025-0027 o
SiteH 25-025-0042 Ł 20 -
Sitel 25-025-0043 Ł
SiteJ 25-027-0016 JJ
c
0
1 <
...
1 1 1 1
1 ^winter P
2-spring
3=summer
-1-fall ^ ~





















1234 1234 1234 1234 1234 1234 1234 1234 1234 1234
KLMNOPQRS
Mean 11.4 7.2 10.0 9.7 8.9 10.1 11.9 10.5 9.7
Obs 345 183 361 362 362 1027 321 313 998
SD 7.4 5.3 6.7 6.0 5.8 6.6 6.9 6.5 6.5
40-
AQSSitelD
SiteK 25O27O023
SiteL 33001-2004
SiteM 33011-1015
30-
SiteN 33013-1006 "
SiteO 33O15O014 -^
O)
SiteP 44007O022 ^
SiteQ 44007O026 <=
O
SiteR 44007O028 '^20-
SiteS 44007-1010 Z
d
o
o I
0 | j ||
10-
1=winter
2=spring
3= summer
4=fall „.






















                            1234 1234 1234  1234  1234 1234 1234 1234  1234
Figure 3-20.   Seasonal distribution of 24-h avg PM2.s concentrations by site for Boston, MA,
             2005-2007. Box plots show the median and interquartile range with whiskers
             extending to the 5th and 95th percentiles at each site during (1) winter
             (December-February), (2) spring (March-May), (3) summer (June-August) and (4)
             fall (September-November).
December 2009
3-62

-------
Table 3-11.     Inter-sampler comparison  statistics for each pair of 24-h PM2.6 monitors reporting to

                    AQS for Boston, MA.


 Site        ABCDEFGH              I              J
  A	1.00	0.80	0.77	071	0.84	0.79	0.78	0.79	0.79	0.77
                        (6.6,0.21)	(6.2, 0.22)	(6.9, 0.23)	(4.8,0.19)	(8.1,0.23)	(7.7, 0.24)	(6.8, 0.22)	(7.9, 0.25)	(7.5, 0.24)
                          326	318	323	329	318	319	325	338	310
                          1.00	0.92	0.87	0.87	0.90	0.90	0.90	0.90	0.85
                                      (4.1,0.17)	(4.1,0.18)	(4.7,0.19)	(6.3, 0.21)	(6.2, 0.23)	(4.9,0.19)	(7.1,0.26)	(5.5, 0.21)
                                 	328	331	339	326	323	333	343	317
                                        1.00	0.90	0.85	0.90	0.89	0.90	0.88	0.86
                                      (0.0, 0.00)	(3.5,0.17)	(5.3,0.21)	(6.3, 0.23)	(6.3, 0.24)	(5.0, 0.20)	(6.8, 0.26)	(6.2,0.21)
                                        342           321            331           316           318            326           336           311
LEGEND
Pearson R
E (P90, COD)
n
(0.0, 0.00)
355


(5.6, 0.20)
336
1.00
(0.0, 0.00)
(5.8,0.21)
324
0.90
(5.9,0.19)
(5.8, 0.22)
329
0.90
(5.8,0.21)
(4.6,0.19)
332
0.89
(5.0,0.19)
(7.0, 0.26)
345
0.87
(6.9, 0.24)
(5.8,0.19)
313
0.87
(5.4, 0.20)
                                                                                  1.00           0.94            0.94           0.92           0.92
                                                                                              (3.8,0.14)	(3.5,0.15)	(4.5,0.17)	(5.4,0.18)
                                                                                   349            324            324            339            310
                                                                                                 1.00            0.94           0.94           0.89
                                                                                                            (4.0,0.16)	(4.3,0.15)	(5.7, 0.20)
                                                                                                               325            338            308
                                                                                                               1.00           0.93           0.89
                                                                                                                           (4.7,0.19)	(5.0,0.17)
                                                                                                               349            342            318
                                                                                                                             1.00           0.86
                                                                                                                             1015           330
                                                                                                                                           1.00
                                                                                                                                           335
December 2009                                                      3-63

-------
Site
A


B


C


D


E


F


G


H


1


J


K


L


M


N


0


P


Q


R


S
K
0.77
(8.1,0.23)
320
0.86
(6.6,0.21)
329
0.86
(6.9,0.21)
321
0.88
(6.4,0.19)
325
0.87
(6.3, 0.20)
333
0.91
(4.7,0.17)
323
0.90
(5.0,0.19)
320
0.90
(4.4,0.17)
327
0.87
(6.1,0.20)
341
0.95
(3.0,0.14)
316
1.00
(0.0, 0.00)
346






















L
0.61
(8.3, 0.29)
173
0.80
(6.2, 0.23)
175
0.89
(4.8, 0.23)
173
0.79
(5.7, 0.25)
174
0.72
(8.3, 0.27)
179
0.78
(9.6, 0.33)
168
0.77
(9.0, 0.33)
172
0.75
(9.4, 0.30)
175
0.75
(10.0,0.36)
181
0.73
(9.2, 0.28)
167
0.71
(10.3,0.31)
170
1.00
(0.0, 0.00)
183






LEGEND
Pearson R
(P90, COD)
n







M
0.71
(8.0, 0.23)
324
0.87
(5.3,0.19)
331
0.93
(4.4,0.17)
323
0.91
(3.5,0.16)
329
0.83
(5.8,0.17)
338
0.90
(5.3,0.18)
323
0.90
(5.3,0.19)
326
0.88
(4.9,0.18)
332
0.86
(6.7, 0.22)
352
0.87
(5.2,0.18)
314
0.88
(6.0,0.16)
326
0.89
(6.7, 0.24)
176
1.00
(0.0, 0.00)
361
















N
0.68
(7.9, 0.23)
334
0.83
(6.0, 0.21)
341
0.90
(4.6,0.19)
335
0.85
(4.7,0.19)
339
0.79
(6.3, 0.20)
347
0.85
(6.4, 0.20)
334
0.85
(6.3, 0.20)
335
0.83
(5.6, 0.21)
341
0.82
(7.2, 0.23)
356
0.84
(5.9, 0.20)
326
0.85
(6.5,0.19)
337
0.91
(5.9, 0.23)
181
0.94
(3.8, 0.13)
341
1.00
(0.0, 0.00)
362













0
0.73
(7.0, 0.22)
331
0.88
(4.7,0.18)
336
0.93
(3.8,0.18)
328
0.86
(4.2,0.18)
334
0.84
(4.8,0.18)
343
0.85
(7.5, 0.22)
330
0.87
(7.0, 0.22)
329
0.84
(6.8,0.21)
336
0.83
(8.2, 0.25)
357
0.80
(7.5, 0.22)
323
0.81
(8.2, 0.22)
332
0.90
(4.8,0.21)
177
0.90
(4.6,0.16)
336
0.90
(4.4,0.17)
346
1.00
(0.0, 0.00)
362










P
0.87
(5.3,0.18)
326
0.86
(5.6,0.19)
335
0.83
(5.9,0.21)
329
0.80
(6.2, 0.20)
342
0.91
(4.5,0.17)
343
0.89
(5.2,0.16)
336
0.88
(5.5,0.17)
383
0.89
(4.5,0.16)
335
0.88
(6.1,0.20)
957
0.90
(5.0,0.17)
321
0.89
(5.2,0.16)
331
0.68
(10.0,0.29)
181
0.83
(5.5,0.16)
345
0.77
(6.7,0.19)
347
0.80
(5.8,0.19)
348
1.00
(0.0, 0.00)
1027







Q
0.81
(7.2, 0.23)
292
0.80
(7.9, 0.26)
300
0.79
(7.8, 0.26)
290
0.75
(7.8, 0.25)
300
0.86
(6.3, 0.22)
306
0.86
(6.0,0.16)
295
0.86
(5.3,0.17)
296
0.86
(6.0,0.19)
299
0.84
(6.0, 0.16)
314
0.86
(5.9, 0.20)
283
0.86
(5.8, 0.18)
296
0.63
(12.1,0.35)
153
0.81
(7.4, 0.20)
300
0.75
(8.1,0.22)
309
0.75
(8.8, 0.25)
304
0.95
(3.6,0.14)
307
1.00
(0.0, 0.00)
321




R
0.85
(5.6, 0.20)
285
0.85
(5.7,0.21)
288
0.81
(6.2, 0.23)
281
0.79
(6.2,0.21)
287
0.88
(4.9, 0.18)
295
0.88
(4.9, 0.16)
281
0.87
(5.2, 0.17)
282
0.87
(4.5, 0.16)
289
0.85
(6.0,0.18)
306
0.87
(5.3, 0.17)
272
0.87
(5.5,0.16)
286
0.72
(9.1,0.30)
149
0.82
(5.8,0.17)
288
0.78
(6.4, 0.20)
297
0.79
(6.8,0.21)
292
0.97
(2.0, 0.09)
299
0.92
(3.1,0.13)
268
1.00
(0.0, 0.00)
313

S
0.86
(5.2,0.18)
306
0.85
(6.0,0.19)
314
0.82
(6.0,0.21)
309
0.80
(5.8, 0.20)
321
0.91
(3.9,0.17)
324
0.89
(5.5,0.17)
316
0.88
(5.7,0.19)
356
0.88
(5.1,0.17)
314
0.87
(6.3,0.21)
936
0.88
(5.2,0.18)
302
0.88
(5.5,0.18)
313
0.69
(9.8, 0.29)
164
0.84
(5.1,0.16)
326
0.78
(6.2,0.19)
327
0.80
(6.0,0.19)
330
0.97
(2.1,0.08)
943
0.94
(4.0,0.16)
290
0.94
(2.7,0.12)
280
1.00
(0.0, 0.00)
998
December 2009
3-64

-------
        A
      01
                Pittsburgh Combined  Statistical Area
                        Pittsburgh CSA
                     •  PM2.5 Monitors
                     	 Interstate Highways
                        Major Highways
                        0   10   20       40       60       80
                            100
                           —i Kilometers
Figure 3-21.  Locations of PM2.s monitors and major highways, Pittsburgh, PA.
December 2009
3-65

-------
Mean 15.1 19.8 13.2 13.6 15.1 16.4
Ots 1063 1066 306 165 332 337
SD 8.9 14.7 8.0 8.5 9.0 9.5
70-
AQS Site ID
Site A 42-003-0008
SteB 42-003-0064 60"
SiteC 42-003-0067
SiteD 42-003-0095 ~ 50_
SitEE 42-003-1008 -5
Cft
SteF 42-003-1301 .a
C 40 -
O
ro
Ł
3J
u
c
O
u
20 -
1 0 ™
1 ^winter
2=spring
3=summer
4=fall 0 -
















































1234 234 234 1234 1234 234
G H j K L
Mean 15.3 16.4 15.5 14.8 13.4 15.4
Obs 171 328 354 345 966 350
SD 8.3 9.3 8.6 8.0 8.6 8.7
70 -
AQS Site ID
SiteG 42-003-3007
SteH 42-007-0014 60 "
Sitel 42-125-0005
SiteJ 42-125-0200 ~ cn
F
SteK 42-125-5001 -C
cn
SteL 42-129-0008 ^
c 40 -
O
I 30-
u
c
O
u
20 -
1 -winter
3=summer
4=fall o -








































                                    1234  1234  1234  1234  1234  1234
Figure 3-22.   Seasonal distribution of 24-h avg PM2.s concentrations by site for Pittsburgh, PA,
             2005-2007. Box plots show the median and interquartile range with whiskers
             extending to the 5th and 95th percentiles at each site during (1) winter
             (December-February), (2) spring (March-May), (3) summer (June-August) and (4)
             fall (September-November).
December 2009
3-66

-------
 Table 3-12.     Inter-sampler comparison  statistics for each pair of 24-h  PM26 monitors reporting to

                      AQS for Pittsburgh, PA.


         ABCDEFGH             I            JKL
 A      1.00	0.79	0.95	0.92	0.93	0.95	0.95	0.85	0.90	0.93	091	0.88
      (0.0,0.00)     (15.9,0.19)     (5.6,0.13)     (4.7,0.11)     (4.7,0.11)      (4.9,0.10)      (3.8,0.10)      (6.4,0.13)      (6.4,0.13)      (5.0,0.12)     (6.0,0.13)     (5.6,0.12)
	1063	1035	298	164	323	329	170	319	344	337	934	340
_B	1.00	071	0.65	0.80	0.85	0.76	0.69	071	0.68	0.68	0.67
	(0.0,0.00)     (16.9,0.24)     (17.4,0.25)     (14.4,0.19)     (12.5,0.14)    (15.7,0.20)    (17.0,0.19)     (15.7,0.21)    (17.8,0.23)     (19.3,0.25)     (15.9,0.21)
	1066	303	165	329	335	171	324	350	341	938	346
_C	1.00	0.93	0.90	091	0.94	0.80	0.93	0.96	0.95	0.91
	(0.0,000)     (2.8,0.09)     (6.6,0.16)      (8.7,0.17)      (6.0,014)      (9.4,0.19)      (6.7,0.15)      (4.6,012)     (4.5,0.10)     (6.5,0.15)
	306	144	282	282	148	268	290	286	270	286
_D	1.00	0.84	0.87	091	0.79	0.89	091	0.97	0.85
	(0.0,0.00)     (6.4,0.15)      (8.5,0.16)      (5.8,0.13)      (9.2,0.17)      (5.9,0.13)      (4.6,011)     (3.1,0.08)     (6.5,0.15)
	165	153	161	158	156	158	155	146	157
_E	1.00	0.90	0.90	0.84	0.85	0.86	0.88	0.83
	(0.0,0.00)      (6.4,0.13)      (6.5,0.13)      (6.8,0.14)      (8.3,0.16)      (7.7,0.16)     (7.6,0.15)     (7.3,0.15)
                                                            332          313          157          295          320          315          290          318
                         LEGEND         	
                                         	1.00	0.91	0.82	0.88	0.88	0.89	0.86
                        Yearson K        	(0.0,0.00)      (6.7,0.13)      (7.4,0.14)      (7.1,0.15)      (7.9,0.15)     (8.8,0.17)     (7.0,0.14)
                        (P90, COD)        	337	yff	3Q2	327	319	296	322
                            n                                                         1.00          0.78          0.94          0.93          0.90          0.91
                                                                                                 (7.3,0.16)      (4.0,0.10)      (5.0,0.11)     (6.6,0.15)     (5.0,0.13)
                                                                                                   159          163          159           149
                                                                                                   1.00          0.80          0.78          0.82
                                                                                                              (8.4,0.15)      (8.2,0.17)     (9.0,0.18)     (9.2,0.18)
                                                                                                   328          317          309
                                                                                                                1.00          0.93
                                                                                                                           (5.0,011)     (7.2,0.16)
                                                                                                                354          334           310
                                                                                                                             1.00
                                                                                                                           (00,0.00)     (5.5,0.12)     (5.9,0.13)
                                                                                                                             345           302
                                                                                                                                        (0.0, 0.00)     (6.9, 0.15)
 December 2009                                                          3-67

-------
             Los Angeles Core Based  Statistical Area
        A
      Ql
          r
                  \,
                       | Los Angeles CBSA
                     •  PM2.5 Monitors
                    	 Interstate Highways
                        Major Highways
                            0  10  20      40      60      80
                           100
                           —i Kilometers
Figure 3-23.   Locations of PM2.6 monitors and major highways, Los Angeles, CA.
December 2009
3-68

-------
         SiteA
         SteB
         SiteC
         SteD
         SiteE
         SiteF
         SiteG
         SiteH
         Stel
         SteJ
         SteK
AQSSitelD
06-037-0002
06-037-1002
06-037-1103
06-037-1201
06-037-1301
06-037-2005
06-037^1002
06-037-4004
06-037-9033
06-059-0007
06-059-2022
                1=winter
                2=spring
                3=summer
                4=fall
ABCDEFGHI
Mean 16.1 17.0 16.7 13.3 16.7 14.3 14.7 14.2 8.2
Obs 862 308 1004 291 327 334 946 990 221
SD 10.8 10.2 9.8 7.5 9.3 8.9 8.4 7.7 3.8
60 -
50 -
IE
C
O
ro 30-
c
CJ
t=
O 20 -
1 0 -
o -









1 .
t ii











w

J K
14.4 10.9
999 318
8.5 6.4










!



















I11











|1

                            1234  1234 1234  1234 1234  1234 1234 1234  1234 1234  1234
Figure 3-24.    Seasonal distribution of 24-h avg PM2.s concentrations by site for Los Angeles,
               CA, 2005-2007. Box plots show the median and interquartile range with whiskers
               extending to the 5th and 95th percentiles at each site during (1) winter
               (December-February), (2) spring (March-May), (3) summer (June-August) and (4)
               fall (September-November).
Table 3-13.   Inter-sampler comparison statistics for each pair of 24-h PM2.6 monitors reporting to
             AQS for Los Angeles, CA.
A
A 1.00
(0.0, 0.00)
862
B


C


D


E


F


G


H


I


J


K
B
0.86
(9.0, 0.18)
252
1.00
(0.0, 0.00)
308










LEGEND
Pearson R
(P90, COD)
n











C D
0.87 0.81
(7.7,0.16) (9.0,0.19)
803 238
0.92 0.87
(5.5,0.11) (9.1,0.19)
293 250
1.00 0.80
(0.0, 0.00) (9.6, 0.20)
1004 274
1.00
(0.0, 0.00)
291



















E
0.80
(9.7,0.21)
262
0.83
(9.0,0.15)
278
0.89
(5.8,0.11)
315
0.69
(10.9,0.23)
263
1.00
(0.0, 0.00)
327
















F
0.88
(5.8,0.14)
269
0.88
(7.6,0.15)
279
0.92
(6.4,0.13)
319
0.77
(7.4,0.18)
263
0.79
(9.1,0.19)
301
1.00
(0.0, 0.00)
334













G
0.68
(11.5,0.22)
761
0.77
(9.8, 0.17)
268
0.84
(9.0, 0.15)
880
0.63
(11.3,0.22)
256
0.95
(5.9,0.11)
289
0.70
(10.5,0.18)
290
1.00
(0.0, 0.00)
946










H
0.64
(12.4,0.23)
793
0.73
(11.6,0.18)
282
0.79
(10.0,0.17)
913
0.60
(11.1,0.22)
268
0.92
(7.6, 0.13)
301
0.70
(9.2, 0.19)
302
0.96
(4.0, 0.09)
859
1.00
(0.0, 0.00)
990







I
0.30
(18.0,0.36)
179
0.31
(24.1,0.38)
177
0.29
(18.6,0.38)
213
0.41
(14.8,0.31)
164
0.34
(19.7,0.39)
192
0.33
(14.8,0.34)
184
0.23
(17.0,0.35)
194
0.26
(15.3,0.34)
208
1.00
(0.0, 0.00)
221




J
0.70
(10.5,0.21)
804
0.74
(11.9,0.19)
292
0.82
(9.4,0.16)
920
0.64
(9.6,0.21)
274
0.88
(8.2,0.15)
307
0.69
(9.8,0.19)
311
0.92
(5.4,0.12)
882
0.91
(5.9,0.12)
914
0.21
(18.3, 0.35)
205
1.00
(0.0, 0.00)
999

K
0.82
(11.4,0.23)
259
0.71
(15.0,0.27)
277
0.78
(13.2,0.25)
305
0.60
(11.6,0.23)
261
0.76
(13.7,0.27)
291
0.72
(9.9,0.21)
293
0.78
(11.0,0.21)
277
0.78
(9.5,0.21)
294
0.31
(9.7, 0.28)
180
0.84
(9.8, 0.19)
298
1.00
(0.0, 0.00)
318
      To further investigate the relationship between correlation and distance, Figure 3-25 through
Figure 3-27 plot inter-sampler correlation as a function of distance between monitors for PM2.5 in
December 2009
                                3-69

-------
Boston, Pittsburgh, and Los Angeles. These three cities were selected to illustrate how this
relationship varies across urban areas with different topography and climatology as well as different
PM2.5 sources, compositions and monitor densities. Plots are provided in Annex A for all 15
CSAs/CBSAs under investigation beginning with Figure A-39. The Boston data exhibit the strongest
relationship between inter-sampler correlation and distance, with average inter-sampler correlation
remaining higher than 80% when samplers are 95 km apart (R2 = 0.55). This small amount of
variability is expected given the consistency between distributions shown in the corresponding box
plots (Figure 3-20). The Pittsburgh data show some reductions in inter-sampler correlations at short
distances, with the samplers at Sites  B  and G having only 76% correlation with a  distance of less
than 4 km. Site B is located in Liberty, PA, a mountainous suburb of Pittsburgh where emissions
from steel manufacturing and frequent stable conditions in the planetary boundary layer cause
localized events of elevated concentration. In contrast, Site G is in the neighboring town of Clairton,
PA, located at a lower elevation on the bank of the opposite side of the Monongahela River from
Liberty. On average, inter-sampler correlation remained higher than 80% when samplers were
separated by 61 km, but in this case with much greater scatter (R2 = 0.22) than observed in the
Boston data. This scatter is driven by the measurements at Site B; Figure 3-22 shows an elevated
mean and variability for this site compared with other monitors situated around the Pittsburgh CSA.
When data from Site B are removed, the inter-sampler correlation vs. distance plot for Pittsburgh
PM2.5 resembles the one from Boston (with R2 increasing to 0.68). The Los Angeles data exhibit a
much steeper slope, with average inter-sampler correlation remaining higher than 80% when
samplers are 29 km apart (R2 = 0.74). This suggests that other factors, such as mountainous
topography separating monitors, the  distribution of traffic, re suspension of crustal components, and
occurrence of stable boundary layers, may cause more spatial variation in the PM2.5 concentration
profile within the Los Angeles region when compared with other parts of the country.  The Site I
monitor, separated from the rest of the  Los Angeles  region by the San Gabriel Mountains as
mentioned above, provides the low correlations grouped in the lower right portion of Figure 3-27. It
should also be noted in examining Figure 3-19, Figure 3-21, and Figure 3-23 that some monitors are
often  located close to major interstate highways while others in the same urban area are not. These
differences in proximity of monitors to nearby major roads may also result in lower inter-monitor
correlations.
December 2009                                  3-70

-------
          0.8
          0.6
                   10       20      30      40       50      60

                                        Distance Between Samplers (km)
                                                                 70      80      90      100
Figure 3-25.   Inter-sampler correlations for 24-h PM2.s as a function of distance between
               monitors in Boston, MA.
                           **
          0.8
          0.6
                                «»»««»   «
                   10      20      30      40       50      60

                                         Distance Between Samplers (km)
                                                                 70      80
                                                                                       100
Figure 3-26.   Inter-sampler correlations for 24-h PM2.s as a function of distance between
               monitors in Pittsburgh, PA.
December 2009
3-71

-------
       0.8 -
       0.6 -
     g
     8
       0.4 -
       0.2 -

                 10      20      30      40       50       60       70

                                       Distance Between Samplers (km)
                                                                        80
                                                                               90
                                                                                       100
 Figure 3-27.   Inter-sampler correlations for 24-h PM2.s as a function of distance between
               monitors in Los Angeles, CA.
      PMlO-2.5
      Given the limited number of co-located low-volume FRM PM10 and FRM PM2.5 monitors,
only a very limited investigation into the intra-urban spatial variability of PMi0_2.5 was possible using
AQS data. Of the 15 cities under investigation, only six (Atlanta, Boston, Chicago, Denver, New
York and Phoenix) contained data sufficient for calculating PMi0_2.5 according to the data
completeness and monitor specification requirements discussed earlier. Figure 3-28 contains box
plots of PMio_2.5 for one or two available sites per CSA/CBSA providing  adequate PMi0_2.5
concentration data. For Boston, the correlation between the two sites for  PM10_2.5 was 0.45 compared
with 0.73 for PM2 5  alone and 0.84 for PM10 alone (using the same two monitoring sites). For New
York, the correlation was slightly higher for the two sites: 0.74 for PMi0_2.5 compared with 0.93 for
PM2.5 alone and 0.82 for PMi0 alone. The COD for PMi0_2.5 also increases in both cities compared
with PM2 5 and PMi0 alone, suggesting less spatial homogeneity for thoracic coarse particles
compared with fine particles. Wilson and Suh (1997, 077408) reported PMi0_2.5 correlations between
eight sites in Philadelphia ranging from 0.14 to 0.63 with an average of 0.38. This was considerably
less than the corresponding average correlation for PM25 (r = 0.90) and PM10 (r = 0.87) from the
same study. Thornburg et al. (2009,  190999) also reported a high degree  of spatial variability in
PMio_2.5 in Detroit with between-monitor correlations ranging from 0.03 to 0.76.  These results
suggest that local sources can have a substantial impact on PMi0_2.5 concentrations, resulting in a
higher degree of spatial variability in PMi0_2.5 relative to PM25 or PMi0.
December 2009
3-72

-------
                Atlanta
                              Boston
                                           Chicago
                                                        Denver
                                                                     New York
                                                                                  Phoenix
                                                                   1234  123
Figure 3-28.   Seasonal distribution of 24-h avg PMi0.2.s concentrations by site for Atlanta, GA;
              Boston, MA; Chicago, IL; Denver, CO; New York City, NY; and Phoenix, AZ;
              2005-2007. Box plots show the median and interquartile range with whiskers
              extending to the 5th and 95th percentiles at each site during (1) winter
              (December-February), (2) spring (March-May), (3) summer (June-August) and (4)
              fall (September-November). Note the different concentration scales on the y-axes.
      PM10

      PM10 mass concentration has been shown to vary as much as a factor of five over urban-scale
distances of 100 km or less, and by a factor of 2 or more on scales as small as 30 km in an analysis
of California air quality (Alexis et al., 2001, 079886). This can be attributed to the rapid Vd and
resulting short atmospheric lifetime of the coarse-mode particles making up much of PMi0 mass. As
a result, local emission sources often dominate PMi0 annual average mass at certain monitors. Data
from the 15 CS As/CBS As were used to investigate urban variability in PMi0 reported to the AQS
database.
      Maps of PMio monitor locations and box plots of seasonal PMi0 mass concentration data are
provided for Boston (Figure 3-29 and Figure 3-30), Pittsburgh (Figure 3-31  and Figure 3-32), and
Los Angeles (Figure 3-33 and Figure 3-34)  similar to the PM2.5 maps and box plots shown earlier in
Figure 3-19 through Figure 3-24. Annex A,  Figures A-82 through A-125 incorporate similar
information for all 15 CSAs/CBSAs. Table  3-14 through Table 3-16 contain pair wise, within-city
comparison statistics (R, P90, COD and n, as defined above) for PMi0 measured at the available
monitors in Boston (Table 3-14), Pittsburgh (Table 3-15) and Los Angeles (Table 3-16); all 15
CSAs/CBSAs are included in Annex A, Tables A-35 through A-49.
      Boston is an example of a city with a wide range in  concentrations measured at different sites.
Inter-monitor variation in PMi0 is frequently larger than the seasonal variation measured at any given
site. Pairwise correlations between monitors in Boston range from 0.45 to 0.95  in Table 3-14.
Pittsburgh is an example of a city with a large number  of PMi0 monitors providing consistent values
with a select few reporting higher concentrations (sites D,  H, I and K in Figure  3-32). This illustrates
the potential influence of localized point or area sources or topography. Correlations between
monitors in Pittsburgh range from 0.47 to 0.97 in Table 3-15. Los Angeles shows a high degree of
between-season and within-season variability, which is on the order of the between-monitor
variation. Correlations between monitors in Los Angeles range from 0.29 to 0.93 in Table 3-16. Once
again, the lowest correlations are with the monitor separated from the other monitors by the San
Gabriel  Mountains (Site E in Figure 3-33).
December 2009
3-73

-------
                  Boston  Combined Statistical Area
        A
      01
                        Boston CSA
                    •   PMio Monitors
                    	 Interstate Highways
                        Major Highways
                                     0 10 20    40    60    80
                          100
                          ^Kilometers
Figure 3-29.    Locations of PM10 monitors and major highways, Boston, MA.
December 2009
3-74

-------
            Site A
            SiteB
            SiteC
            SiteD
            SiteE
            SiteF
            SiteG
            SiteH
AQS Site ID
25-025-0042
25-027-0023
33-011-0020
33-015-0014
44-003-0002
44-007-0022
44-007-0026
44-007-0027
                  1 ^winter
                  2=spring
                  3=summer
                  4=fall
ABCDEFGH
Mean 16.4 21,6 16.5 14.8 10.7 17.0 21.3 18.8
Obs 191 174 182 175 171 182 169 168
SD 7.7 11.9 9.2 8.2 7.0 8.7 10.8 9.4
60 -
50 -
40 -
30 -
20-
10-
o -































1
1







                                  1234  1234 1234 1234  1234  1234  1234
                                                                               234
Figure 3-30.    Seasonal distribution of 24-h avg PMi0 concentrations by site for Boston, MA,
               2005-2007. Box plots show the median and interquartile range with whiskers
               extending to the 5th and 95th percentiles at each site during (1) winter
               (December-February), (2) spring (March-May), (3) summer (June-August) and (4)
               fall (September-November).
Table 3-14.   Inter-sampler comparison statistics for each pair of 24-h PMio monitors reporting to AQS
             for Boston, MA.
Site A B
A 1.00 0.69
(0.0,0.00) (15.0,0.22)
191 169
B 1.00
(0.0, 0.00)
174
C


D


E LEGEND
Pearson R
(P90, COD)
F n


G

C
0.69
(12.0,0.20)
179
0.66
(17.0,0.24)
167
1.00
(0.0, 0.00)
182











D
0.73
(10.0,0.22)
173
0.56
(19.0,0.28)
161
0.72
(10.0, 0.22)
170
1.00
(0.0, 0.00)
175








E
0.71
(13.0,0.30)
171
0.45
(24.0, 0.39)
158
0.47
(17.0,0.33)
168
0.63
(11.0,0.29)
163
1.00
(0.0, 0.00)
171





F
0.84
(8.0, 0.14)
182
0.69
(15.0,0.21)
169
0.62
(12.0,0.21)
179
0.68
(10.0,0.23)
173
0.84
(13.0,0.29)
171
1.00
(0.0, 0.00)
182


G
0.70
(150,0.20)
169
0.77
(12.0,0.17)
156
0.64
(16.0,0.26)
166
0.59
(19.0,0.30)
161
0.58
(22.0, 0.38)
161
0.81
(11.0,0.16)
169
1.00
(0.0, 0.00)
H
0.79
(10.0,0.17)
167
0.65
(16.0,0.20)
154
0.59
(16.0,0.24)
164
0.69
(13.0,0.26)
158
0.80
(15.0,0.33)
157
0.95
(5.0,0.11)
167
0.79
(10.0,0.13)
169 154
H





1.00
(0.0, 0.00)
168
December 2009
                             3-75

-------
        A
      01
                Pittsburgh Combined  Statistical Area
                        0    10   20
  40       60
                        Pittsburgh CSA
                        PMio Monitors
                        Interstate Highways
                        Major Highways
80
 100
m Kilometers
Figure 3-31.  Locations of PM10 monitors and major highways, Pittsburgh, PA.
December 2009
3-76

-------
Mean 21.2 18.2 21.8 27.7 23.4 19.6 18.4 29.7 25.2
Obs 1077 1019 1083 1087 176 179 978 182 1022
SD 12.9 11.4 12.3 20.3 11. 9.9 11.7 16.8 19.3
90-
AQSStelD
SfcA 42-003-0002 80-
SitB 42-0034021
SiteC 42-OB-0031 70-
SiteD 42-003-0064 ~
SteE 42-003-0092 ^ 60"
Site F 42-003-0095 3
SiteG 42-003-0116 "^ 50"
SiteH 42-003-1301 ~
03 40-
c
S 30-
c
o
u 20-
10-
1=winter
2=spring 0 "
3=summer
4=fall _t o -
















1




















f




234 234 234 1234 234 234 234 234 1234
J K L M N O P Q
Wban 20.1 36,5 26.3 26.4 21,7 19.7 27.3 21.1
Obs 177 1061 1051 1069 1092 167 178 1079
SD 10.3 26,7 16.3 15,0 12,4 11.0 12.0 11,4
120-
AQS Site ID , , o .
Site I 42-003-3006
SiteJ 42-003-3007 10°"
SiteK 42-003-7004
--, 90 -
SteL 42-007-0014 "p
SiteM 42-073-0015 "g, 80-
SteN 42-125-0005 3
c 70-
SteO 42-125-5001 o
SiteP 42-1294007 S 60-
SteQ 42-129-0008 Ł
u
C
O 40-
30-
20-1
1=winter B
2=spring 1 0 - T
3 -summer
4=fall 0 -
















ill
i
F ff


                                 1234  1234 1234 1234  1234 123'
                                                             1234  1234
Figure 3-32.   Seasonal distribution of 24-h avg PMi0 concentrations by site for Pittsburgh, PA,
             2005-2007. Box plots show the median and interquartile range with whiskers
             extending to the 5th and 95th percentiles at each site during (1) winter
             (December-February), (2) spring (March-May), (3) summer (June-August) and (4)
             fall (September-November).
December 2009
3-77

-------
Table 3-15.     Inter-sampler comparison statistics for each pair of 24-h  PMio monitors reporting to AQS
                    for Pittsburgh,  PA.

 Site         ABODE               FGH                I
  A	1.00	0.93	0.93	0.80	0.92	0.89	0.93	0.79	0.86	
                                         (8.0,0.14)	(23.0, 0.21)	(8.0,0.12)	(14.0,0.18)	(8.0,0.14)	(16.0,0.17)	(18.0,0.18)
            1077	1002	1065	1070	175	178	960	181	1005
           	1.00	0.96	0.80	091	0.92	0.97	081	0.89
           	(0.0, 0.00)	(8.0,0.15)	(29.0, 0.24)	(11.0,0.20)	(6.0,0.16)	(5.0,0.10)	(25.0, 0.29)	(22.0, 0.20)
           	1019	1007	1012	163	166	911	169	954
           	1.00	081	0.94	0.93	0.94	0.77	0.87
           	(0.0, 0.00)	(23.0, 0.20)	(6.0,0.11)	(7.0,0.12)	(8.0,0.13)	(21.0,0.22)	(19.0,0.17)
           	1083	1075	173	176	966	179	1010
           	1.00	0.72	0.66	0.76	0.83	0.88
           	(0.0, 0.00)	(21.0,0.20)	(26.0, 0.24)	(27.0, 0.24)	(14.0,0.18)	(16.0,0.14)
           	1087	176	179	970	182	1014
           	1.00	0.90	0.90	0.78	0.77
           	(0.0, 0.00)	(10.0,0.14)	(10.0,0.17)	(20.0, 0.20)	(20.0,0.19)
                  LEGEND           	176	173	154	175	166
                  Pearson R           	1.00	0.94	0.70	0.74
                 (P90, COD)           	(0.0, 0.00)	(7.0,0.12)	(25.0, 0.27)	(25.0, 0.22)
                     n                                                                      179              157              178              168
                                                                                                            1.00              0.70             0.87
                                                                                                                          (22.0, 0.28)	(20.0,0.19)
                                                                                                            978              160              910
                                                                                                                                             0.76
                                                                                                                           (0.0, 0.00)	(17.0,0.20)
                                                                                                                             182              171
                                                                                                                                             1.00
                                                                                                                                             1022
December 2009                                                        3-78

-------
J
A 0.84
(14.0,0.20)
176
B 0.93
(7.0,0.16)
164
C 0.90
(8.0,0.13)
174
D 0.73
(24.0, 0.22)
177
E 0.86
(10.0,0.16)
171
F 0.90
(7.0,0.12)
174
G 0.92
(7.0,0.13)
156
H 0.74
(23.0, 0.26)
176
I 0.79
(22.0, 0.20)
166
J 1.00
(0.0, 0.00)
177
K


L


M


N


0


P


Q
K
0.76
(40.0, 0.30)
1044
0.76
(43.0, 0.36)
986
0.75
(39.0, 0.30)
1049
0.84
(24.0, 0.22)
1055
0.65
(36.0, 0.29)
169
0.57
(41.0,0.34)
172
0.73
(45.0, 0.35)
955
0.68
(26.0, 0.22)
175
0.83
(30.0, 0.25)
992
0.66
(44.5, 0.33)
170
1.00
(0.0, 0.00)
1061
















L
0.88
(15.0,0.18)
1033
0.88
(19.0, 0.23)
982
0.88
(14.0,0.17)
1039
0.80
(20.0,0.18)
1043
0.83
(16.0,0.16)
169
0.82
(20.0, 0.20)
172
0.87
(18.0,0.21)
938
0.77
(15.0,0.18)
175
0.82
(16.0,0.17)
978
0.79
(18.0,0.20)
170
0.74
(31.0,0.26)
1017
1.00
(0.0, 0.00)
1051













M
0.85
(16.0,0.19)
1052
0.81
(20.0, 0.26)
994
0.83
(15.0,0.19)
1057
0.78
(20.0, 0.20)
1061
0.80
(14.0,0.17)
172
0.75
(19.0,0.22)
175
0.78
(19.0,0.24)
952
0.78
(17.0,0.18)
178
0.78
(18.0,0.20)
998
0.72
(18.0,0.22)
173
0.75
(33.0, 0.24)
1035
0.87
(13.0,0.16)
1025
1.00
(0.0, 0.00)
1069










N
0.86
(11.0,0.16)
1074
0.91
(10.0,0.16)
1016
0.89
(9.0,0.12)
1080
0.76
(25.0, 0.20)
1084
0.84
(12.0,0.14)
176
0.86
(11.0,0.14)
179
0.89
(9.0,0.15)
975
0.74
(21.0,0.22)
182
0.81
(20.0, 0.17)
1019
0.88
(8.0,0.13)
177
0.70
(40.0, 0.30)
1058
0.85
(16.0,0.17)
1048
0.74
(18.0,0.21)
1067
1.00
(0.0, 0.00)
1092







0
0.77
(16.0,0.22)
166
0.76
(12.0,0.19)
157
0.78
(12.0,0.18)
164
0.57
(28.0, 0.26)
167
0.77
(14.0,0.19)
161
0.83
(9.0,0.15)
164
0.81
(11.0,0.17)
146
0.60
(27.0, 0.29)
167
0.66
(26.0, 0.24)
158
0.78
(11.0,0.17)
163
0.47
(44.0, 0.36)
160
0.70
(22.0, 0.24)
160
0.64
(19.0,0.26)
163
0.72
(13.0,0.18)
167
1.00
(0.0, 0.00)
167




P
0.78
(15.0,0.19)
177
0.83
(18.0,0.28)
165
0.88
(13.0,0.19)
175
0.64
(20.0, 0.25)
178
0.84
(13.0,0.16)
172
0.84
(16.0,0.22)
175
0.84
(17.0,0.26)
157
0.65
(19.0,0.22)
177
0.69
(21.0,0.25)
167
0.86
(16.0,0.21)
173
0.58
(34.0, 0.30)
171
0.74
(17.0,0.21)
171
0.67
(17.0,0.22)
174
0.86
(14.0,0.20)
178
0.75
(18.0,0.25)
163
1.00
(0.0, 0.00)
178

Q
0.86
(11.0,0.15)
1061
0.88
(10.0,0.18)
1003
0.90
(9.0,0.12)
1067
0.74
(26.0,0.21)
1071
0.85
(11.0,0.15)
174
0.86
(9.0,0.14)
177
0.86
(10.0,0.16)
967
0.76
(21.5,0.24)
180
0.78
(22.0, 0.19)
1009
0.86
(8.0,0.15)
175
0.68
(43.0, 0.30)
1048
0.80
(18.0,0.19)
1035
0.77
(18.0,0.19)
1053
0.86
(10.0,0.14)
1076
0.69
(14.0,0.19)
165
0.84
(15.0,0.21)
176
1.00
(0.0, 0.00)
1079
December 2009                                        3-79

-------
             Los Angeles Core Based Statistical Area
      01
         r
                        Los Angeles CBSA
                     •  PMio Monitors
                     	 Interstate Highways
                        Major Highways
                            0   10  20       40      60
                    80
 100
—i Kilometers
Figure 3-33.   Locations of PM10 monitors and major highways, Los Angeles, CA.
December 2009
3-80

-------
                 AQS Site ID
           Site A 06-037-0002
           SiteB 06-037-1103
           SiteC 06-037-4002
           SiteD 06-037-6012
           Site E 06-037-9033
           Site F 06-059-0007
           SiteG 06-059-2022
                             Mean   35.3
                              Obs   169
                               SD   19.8
c
o
                              90 -
   80 -
   70-
   60-
                              50 -
                           C  40-
                           01
                           u
                           030-
                              20 -
                     1=winter
                     2=spring
                     3=summer
                     4=fall
                              1 0 -
    0 -
               31.1
               175
               13.3
 C
31.5
178
19.6
 D
27.3
176
18.1
 E
23.7
985
12.1
 F
33.5
175
37.6
 G
21.6
162
9.4










1234 1234 1234 1234 1234 12





34 1234
Figure 3-34.    Seasonal distribution of 24-h avg PM10 concentrations by site for Los Angeles,
               CA, 2005-2007.  Box plots show the median and interquartile range with whiskers
               extending to the 5th and 95th percentiles at each site during (1) winter
               (December-February), (2) spring (March-May), (3) summer (June-August) and (4)
               fall (September-November).
Table 3-16.   Inter-sampler comparison statistics for each pair of 24-h PM10 monitors reporting to AQS
             for Los Angeles, CA.
Site A
A 1.00
(0.0, 0.00)
169
B


C
LEGEND
Pearson R
D (P90, COD)
n

E


F


G
B C
0.73 0.44
(17.0,0.17) (27.0,0.24)
153 154
1.00 0.61
(0.0,0.00) (14.0,0.14)
175 159
1.00
(0.0, 0.00)
178










D
0.73
(24.0, 0.22)
157
0.57
(21.0,0.24)
159
0.65
(27.0, 0.28)
158
1.00
(0.0, 0.00)
176







E
0.47
(28.0, 0.26)
169
0.52
(23.0, 0.23)
173
0.43
(22.0, 0.24)
176
0.70
(16.0, 0.20)
175
1.00
(0.0, 0.00)
985




F
0.41
(29.0, 0.24)
155
0.42
(15.0,0.16)
162
0.93
(11.0,0.11)
159
0.65
(26.0, 0.28)
161
0.29
(26.0, 0.25)
173
1.00
(0.0, 0.00)
175

G
0.65
(30.0, 0.28)
143
0.73
(20.0, 0.23)
149
0.73
(21.0,0.22)
148
0.57
(19.5,0.24)
150
0.38
(20.0, 0.24)
159
0.65
(21.5,0.22)
150
1.00
(0.0, 0.00)
162
December 2009
                   3-81

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      Figure 3-35 through Figure 3-37 illustrate the relationship between inter-sampler correlation
and distance between sites for PMi0 measurements obtained in Boston, Pittsburgh and Los Angeles.
Annex A contains similar plots for all 15 CS As/CBS As under investigation beginning with Figure A-
84. In each plot, substantially more scatter is observed when compared to those for PM2.5 (Figure
3-25 through Figure 3-27). This is consistent with the variability observed in the seasonal box plots
of concentration shown in Figure 3-30, Figure 3-32, and Figure 3-34. The Boston data exhibit the
strongest relationship between inter-sampler correlation and distance, with average inter-sampler
correlation remaining higher than 80% when samplers are 44 km apart (R2 = 0.61). The lowest
correlations on this plot originate from comparisons between Site B (rural Worcester, MA)  and
samplers located at Sites E (West Greenwich, RI) and G (Providence, RI). Boston is  subject to long
                                            i0
range transport of SO42~, which is a regional pollutant and is a major component of PM2.5 and PM
in the eastern U.S. The Pittsburgh data shows some lower inter-sampler correlations, with one
sampler pair having only 66% correlation within a distance of 2 km. On average, inter-sampler
correlation remained higher than 80% when samplers were also separated by 44 km, but in this case
with much greater scatter (R2 = 0.28) than observed in the Boston data. As seen for the Pittsburgh
PMio box plots in Figure 3-32, sites D, H, I, and K have elevated means and high variability that is
driving the observed scatter. These four sites are all located in mountainous suburbs of Pittsburgh
(North Braddock, PA, Liberty, PA, Lincoln Boro, PA, and Beaver Falls, PA, respectively), where
emissions from steel manufacturing and frequent stable conditions in the planetary boundary layer
cause localized events of elevated concentration. When those four sites are removed, scatter
decreases greatly (R2 = 0.56). The Los Angeles data exhibit a much steeper slope, with average
inter-sampler correlation remaining higher than 80% when samplers are only 30 km apart
(R2 = 0.56). The  lower inter-sampler correlations in part reflect the fact that some of these
monitoring sites  are separated from each other by hills or, in the case of one sited at Lancaster, CA
(Site I), by the San Gabriel Mountains. The Los Angeles data exhibit greater scatter than the
Pittsburgh data. However, the smallest inter-sampler separation distance is 23 km, and there are
relatively fewer PMi0 samplers. Given the present data, it is not possible to judge how data would
correlate on smaller spatial scales.
    0.8
    0.6
    0.4
    0.2
               10
                       20
                               30       40       50       60       70

                                      Distance Between Samplers (km)
                                                                        80
                                                                                 90
                                                                                         100
Figure 3-35.   Inter-sampler correlations for 24-h PM10 as a function of distance between
              monitors in Boston, MA.
December 2009
3-82

-------
    0.8
    0.6
    0.4
    0.2
                              V -   **  *
       0        10        20
                                30       40       50       60        70

                                       Distance Between Samplers (km)
                                                                           80       90       100
Figure 3-36.    Inter-sampler correlations for 24-h PMi0 as a function of distance between
               monitors in Pittsburgh, PA.
    0.8
    0.6
    0.4
    0.2
                                                             4>      4>


                                                            4>       4>
       0        10        20
                                30       40       50       60        70

                                       Distance Between Samplers (km)
                                                                           80       90       100
Figure 3-37.    Inter-sampler correlations for 24-h PMio as a function of distance between
               monitors in Los Angeles, CA.
December 2009
3-83

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      UFPs

      Relatively few studies compare UFP measurements at multiple locations within an urban
center. An early study by Buzorius et al. (1999, 081205) suggested spatial homogeneity in total
particle number concentrations between multiple locations in Helsinki, Finland. They found
correlations in 10-min average at three sites within the city as high as 0.84. The sites, however, were
relatively close together (2 km) and all near the same roadway. There was a high degree of
correlation between traffic intensity and total aerosol number concentrations, suggesting that traffic
was the primary source of the measured particles and the driving force behind the high correlations.
Weekend correlations (0.28-0.47) and correlations with a fourth monitor located 22 km outside the
city (0.05-0.64) were much lower.
      Tuch et al. (2006, 157060) found more spatial heterogeneity in UFP concentrations measured
for an entire year at two locations 1.5 km apart in Leipzig, Germany. Figure 3-38 shows the
correlation as a function of particle size (mobility diameter) dropping off as the particle size
decreases from 0.5 at 100 nm down to 0.2 at 3 nm. Table A-50 in Annex A contains correlation
coefficients of hourly and daily average particle number, surface area and volume concentrations as a
function of particle diameter adapted from the Tuch et al. (2006, 157060) study. For all days
(N = 5481 hourly observations), the correlation between UFPs (10-100 nm) measured at the two
sites was 0.31.
                          1.0
                        c
                        •8 0.6 H
                        1
                        o
                        o
                        c 0-6 -
                          0.4
                        O
                        c
                        05

                        c5
                        8.
                        w
0.2 -
                          0.0
                                     10               100
                                             diameter [nm]

                                           Source: Reprinted with Permission of Nature Publishing Group from Tuch et al. (2006,1570601
Figure 3-38.   Bin-wise Spearman correlation coefficients in aerosol particle number
              concentrations between the Ift (urban background) and the Eisenbahn-strasse
              (city/urban center) sites in Leipzig, Germany.

      The two sites represented in Figure 3-38 and Table A-44 were relatively close to each other,
but one was located in a mixed semi-industrial region while the other was in a street canyon in a
residential neighborhood near busy roadways. This suggests a high degree of spatial heterogeneity in
UFPs driven primarily by differences in nearby source characteristics. Sioutas et al. (2005, 088428)
reviewed studies of the distribution of UFPs and came to the similar conclusion that mobile sources
make a large contribution to UFPs and therefore UFP concentrations can exhibit substantial
variability in space and time. This is to be expected since UFP concentrations drop off much quicker
with distance from roadways than larger particle sizes (Levy et al., 2003, 052661; Reponen et al.,
2003, 088425; Zhu et al., 2005, 157191). Hagler et al. (2009, 191185) showed similar exponential
decreases in UFP number concentrations with distance from the road for multiple locations in the
U.S. Neighborhood-scale variability and near-roadway concentration gradients for UFPs are
discussed further in Section 3.5.1.3.
December 2009
                   3-84

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      PM Constituents

      The pie charts showing PM2.5 composition that were generated using the SANDWICH method
for the 15  CSAs/CBSAs presented earlier in Figure 3-17 and Figure 3-18 represent the average of all
available monitors within each region. Individual pie charts for each monitor are included in Figures
A-127 through A-141 in Annex A and provide an indication of the urban-scale spatial variability in
PM2.5 composition. In the instances where multiple monitors were available, there was a fair degree
of spatial homogeneity in PM2.5 bulk chemistry within each metropolitan area. Some notable
exceptions exist, however. Birmingham and Detroit show variation  in the amount of crustal material,
both spatially and seasonally. Denver exhibits some spatial variation in NO3~ during the winter, the
season with the highest measured PM2 5 mass. Several sites in New  York and one in Pittsburgh have
elevated fractions of EC relative to the other sites within the respective cities, and several sites in
New York have been shown to  have elevated Ni concentrations in PM2 5 samples when compared
with surrounding areas (Peltier and Lippmann, 2009, 197455: Peltier et al., 2008, 197452). In
Phoenix, high winter PM2 5 mass  is site specific and appears to be associated with high OC; the
crustal component also varies and is inversely proportional to total measured mass.


3.5.1.3.   Neighborhood-Scale Variability

      Neighborhood scale spatial variability in the particle concentration profile is  affected by land
and building topography, meteorology, particle size distribution, particle composition, and particle
volatility. Population density at the neighborhood scale is also an important determinant  of the
spatial distribution of PM concentration because population density impacts source prevalence,
source magnitude, topographical-driven ventilation, and heat island effects (Crist et al., 2008,
156372: Makar et al., 2006, 155959: Mfula et al., 2005, 123359: Rigby  and Toumi, 2008, 156050).
      A number of computational and wind tunnel modeling street canyon studies have
demonstrated the potential variability in pollutant concentrations within a street canyon (Borrego et
al., 2006, 155697: Chang and Meroney, 2003, 090298: Kastner-Klein and Plate, 1999, 001961: So
et al., 2005, 110746: Xiaomin et al., 2006, 156165). Influential parameters include street canyon
height to width ratio (H/W), source positioning, wind speed and direction, building shape and
upstream configuration of buildings. Figure 3-39 shows pollutant concentrations obtained from wind
tunnel and computational fluid dynamics simulations of transport and dispersion in an infinitely long
street canyon with a line source centered at the bottom of the canyon (Xiaomin et al., 2006, 156165).
When the  canyon height was equal to the street width (typical of moderate density suburban or urban
fringe residential neighborhoods) and lower background wind speed existed, concentrations on the
leeward canyon wall were four times those of the windward wall near ground level. When the
canyon height was twice the street width (typical of higher-density urban planning) and background
winds were somewhat higher, near ground level concentrations on the windward canyon wall were
roughly three times higher than those measured at the leeward wall. Baldauf et al. (2008, 191017:
2009, 191766) noted that the presence of noise barriers, vegetation, or changes in topography
adjacent to the road can also alter particle dispersion characteristics. Specifically, depressed road
segments, where the road bed is below the surrounding terrain, leads to increased air turbulence and
pollutant dispersion. These results suggest that micro- and neighborhood-scale variation  related to
urban topography may have a significant impact on pollutant concentrations at this scale.
December 2009                                 3-85

-------
                                       windward,      |
                                       measured
                                       windward,  _  _
                                       simulated
                                                     I     leeward,
                                                         measured
                                                     - -  leeward,
                                                          simulated
          1.2
          0.8
          0,4
          0.2
                                                 1.2
       to)
                  20    40     60    80
                  Dimensionless concentration
                                           100
                                                 0.8
                                                 0.6
                                                 0.4
                                                 0.2
                                                  0
     0   100   200   300  400   500  600

-------
        1.00
        0.90
        0.80



        0.70



        0.60
      c

      •3 0.50

      o
      o

        0.40



        0.30



        0.20



        0.10



        0.00
                                             •o- . .  o
                                           00       b- - .
                         RPM25 = -0.0163D+ 10
                          O R2 = 0.2178
       RPM10 = -0.0748D

          R2 = 0.0346
                     . O
o o
   <
•o- •
                    0.5
                                       1.5         2         2.5

                                       Distance Between Samplers (km)
                                                                             3.5
Figure 3-40.    Inter-sampler correlations for 24-h PM2.s and PMi0 as a function of distance
               between monitors for samplers located within 4 km (neighborhood scale).

      Isakov et al. (2007, 156588) compared PM2.s concentrations from a central monitoring site in
Wilmington, DE with PM0.3 measurements taken on a mobile platform driven through mostly quite
residential streets within a 4 km><4 km grid containing the central monitor. Correlations were
generally high (average r = 0.87) over all time periods and locations  monitored, consistent with the
range of correlations for PM2.5 shown in Figure 3-40.

      PMlO-2.5
      Neighborhood-scale variability in PMi0_2.s was  investigated by Chen et al.  (2007, 147318) in
the Raleigh/Durham area of NC. The average correlation between 26 residential  monitors located
throughout the region and a centrally located monitor representing a maximum inter-sampler range
of 60 km was found to be 0.75 for PMi0_2.5 compared  with 0.92 and 0.94 for PM2.5 and PMio,
respectively. Based on this study, neighborhood-scale variability is greater for PMi0_2.5 than for PM2.5
or PM10, matching the conclusion drawn above on the broader urban-scale.

      UFPs

      Moore et al. (2009, 191004) monitored UFP concentrations throughout the Ports of Los
Angeles and Long Beach, through which an interstate highway runs and found that concentrations
varied by a factor of 5-7 across sites with substantial  differences in the daily concentration time
series at each site.  Such variability reflects diversity of the sources (some near the Interstate, some
near the Port), and the influence of changing meteorology over an urban area. In a mobile platform
sampling study, Westerdahl et al. (2005, 086502) and Fruin et al. (2008, 097183) also reported
substantial peaks in UFP concentration when sampling at highways in comparison with a
background site (the University of Southern California) using the same data set.
      Near roadway environments can exhibit high concentration gradients, particularly for UFPs.
Ntziachristos et al. (2007, 089164) observed that the near-road particle size distribution was
December 2009
3-87

-------
substantially higher in the UF mobility diameter range and that these results were very sensitive to
meteorology (rain) and time of day. Baldauf et al. (2008, 190239) reported elevated UFP number
concentrations downwind of a highway in Raleigh, NC, when compared to measurements
approximately 100 m upwind of the road. Hagler et al. (2009, 191185) noted a 5-12% decrease in
number concentrations per 10m distance from the road for a number of studies in the U.S. with
unobstructed air flow.
      After initial emission from a motor vehicle, the evolution of the PM distribution within the
plume is a function of (1) the turbulence that dilutes the plume and (2) evaporation or condensation
of the volatile portion  of the aerosol that results from rapid cooling of the  exhaust. Figure 3-41
shows the size distribution measured by Zhu et al. (2002, 041553) at distances of 17-300 m away
from the roadway (in this case, Highway 710 in Los Angeles) and at an upwind site. It can be seen
that a mode originally measured around 9 nm increases in diameter and decreases in number
concentration as distance from the highway increases. Smaller secondary  modes appear around 30 m
from the roadway with multiple modes at some particle sizes. By 150 m away from the highway, the
size distribution flattens with a small mode around 50 nm. It is clear from the bottom figure that the
number concentration  of larger particles (i.e., 100-220 nm) does not vary as much as UFPs (<100
nm) with increasing distance downwind from the roadway.
                                          10            100

                                          Particle Diameter, Dp (nm)
                                       6-25 nm
                             25-50 nm
                                          50-100 nm
                                        V ----- V --
                             100-220 nm
                                0         100        200        300

                                   Distance down wind from the 710 freeway (m)
                                                 Source: Reprinted with Permission of Elsevier Ltd. From Zhu et al. (2002, 0415531.
Figure 3-41.   Particle size distributions measured at various distances from the 710 freeway in
              Los Angeles, CA (top), and particle number concentration as a function of
              distance from the 710 freeway (bottom).
December 2009
3-88

-------
      Zhou and Levy (2007, 098633) performed a meta-analysis of traffic-related air pollution
literature and found that background pollution and meteorology can have important impacts on the
size of the elevated concentration region around the highway. Zhu et al. (2002, 041553) and Zhang et
al. (2005, 157185) noted in field measurements of UFPs that small particles can be lost due to
evaporation or to coagulation during Brownian diffusion to form bigger particles, resulting in an
upward shift in mode diameter with distance from the roadway. Studies of particle sizes on roads
(Kittelson et al., 2006, 156649; Kittelson et al., 2006, 156648). in tunnels (Venkataraman et al.,
1994, 002475). and upwind and downwind of roads (Zhu et al., 2002, 041553) suggest that for well-
maintained spark-ignition vehicles, a large fraction of the mass of particles emitted from the vehicles
are in the nuclei mode (i.e., smaller than accumulation mode). High-speed highway driving may be
associated with a larger fraction of particle mass  being emitted in the UF size range, while lower
speed operation results in a higher mass fraction  in the accumulation mode (Cadle et al.,  2001,
017192). In situations in which the dilution rates are lower than in a short tunnel or downwind of a
road way, condensation of vapors can give rise to particles in the accumulation mode (Kittelson,
1998, 051098). Diesel engines, in particular, emit black carbon in the lower end of the accumulation
mode, with number emissions dominated by semi-volatile material in the nuclei mode (Kittelson,
1998, 051098: Kittelson et al., 2006, 156649: Kittelson et al., 2006, 156648). Sharp gradients in
black carbon mass have been observed along roadways with high diesel traffic (Zhu et al., 2002,
041553). As the traffic pollution moves downwind, the UFPs may grow into the accumulation mode
by coagulation or condensation. In addition to Gaussian dispersion and wind eddies caused by the
presence of natural and anthropogenic barriers, Sahlodin et al. (2007, 114058) demonstrated that
turbulence produced by vehicles can result in modification of the plume emanating from the
highway. Hence, on-road turbulence could potentially alter the aerosol size distribution. This added
turbulence could cause some evaporation of tiny  nucleation  particles that have not absorbed or
adsorbed onto soot nuclei, which may affect the rate of coagulation (Jacobson et al., 2005, 191187).
The roadway  configuration may also affect particle transport and dispersion. Depressed road
sections, where the road bed is below the surrounding terrain, leads to increased air turbulence and
mixing as air  flows up and out of the road depression. This configuration can result in lower
particulate concentrations and flatten concentration decay curves away from the road. On the other
hand, configurations with the road bed at-grade with surrounding terrain, or elevated above the
surrounding terrain with solid fill material resulted in the highest pollutant concentrations and
sharpest concentration gradients downwind from the road.

      PM Constituents

      The composition of PM will also vary on the neighborhood-scale in response to local sources
and differential dispersion, resulting in variable spatial distribution of individual  components.
Krudysz et al. (2008, 190064) investigated spatial variation in size-fractionated (<0.25 (im,
0.25-2.5 (im, >2.5 (im) PM composition data at four sites located within 3-6 km of each other in the
Long Beach, CA area. Inter-site R2 values in the  0.25-2.5 (im size range were higher for mass
(ranging from 0.56-0.91) than for EC (0.02-0.71) for pair wise site comparisons.  Spatial
heterogeneity in all size ranges investigated was  also  found for several elements associated with
motor vehicle emissions and resuspended road dust including Cu, Mg, Ba, Ca and Al. Viana et al.
(2008, 156135) observed higher concentrations of crustal elements in PM2.5 and PMi0 samples in
rural neighborhoods and higher concentrations of combustion-derived PM2.5 and PMi0, such as EC
and NO3~, in higher density urban areas. Gutierrez-Daban et al. (2005, 155818) examined the mass
distribution of various PAHs under different traffic and urban density conditions. Figure  3-42
displays the distributions for benz[a]pyrene (BaP) at high and low traffic sites at the urban center,
periphery, and industrial areas in Seville, Spain (Gutierrez-Daban et al., 2005, 155818).
Concentrations were nearly an order of magnitude lower for the low traffic urban periphery location
when compared with the high traffic or industrial locations.  Particles smaller than ~ 600 nm had
roughly an order of magnitude higher concentration than those at larger sizes and tended to have a
larger spread in concentrations among sampling sites. Figure 3-43 shows the distributions for sixteen
PAHs at a high traffic location at the city center in Seville, Spain (Gutierrez-Daban et al., 2005,
155818). PAH species varied in concentration by up to two orders of magnitude for each particle size
bin, and the highest concentrations of individual  PAHs were generally found for particles smaller
than approximately 600 nm.  Olson and McDow (2009, 191188) reported decreases by a factor of
1.04-2.37 in select PAH and organic source marker concentrations when comparing measurements
10m and 275 m from a highway in Raleigh, North Carolina. Phuleria et al. (2006, 156867) sampled
December 2009                                 3-89

-------
UFPs and PM2.5 concentrations and PAH species at the mouth of the Caldecott Tunnel in Orinda, CA
and found that the two size classes were highly correlated (R2 = 0.97). Given the size differentials of
each size bin presented in the Gutierrez-Daban et al. (2005, 155818) study, it is possible that the
PM2.5 sampled at the tunnel mouth in the latter study represented secondary PM2.5 that grew from
UFP emissions trapped within the tunnel.
        10000
        1000
         100
          10
                                                                         • HTC
                                                                         • HTP
                                                                         ALTC
                                                                         XLTP
                                                                         XLTIP
                 <0.6
                             1.3-0.6
                                         2.7-1.3         4.9-2.7        10-4.9          >10

                                             Size bin (urn)

                                            Source: Adapted with Permission of Springer-Verlag from Gutierrez-Daban et al. (2005,155818).
Figure 3-42.
Mass distributions for BaP at a high traffic urban center (HTC), high traffic urban
periphery (HTP), low traffic urban center (LTC), low traffic urban periphery (LTP),
and low traffic industrial urban periphery (LTIP) in Seville, Spain.
December 2009
                                3-90

-------
     10000 T
     1000
       10
                                        »Naph
                                        • Ace
                                        AAcey
                                        xFlu
                                        xPhen
                                        • Ant
                                        + Flua
                                        -Pyr
                                        -BaA
                                        oChry
                                        DBbF
                                        ABkF
                                         BaP
                                         InP
                                        ODbA
                                         Bper
              0.6
                         1.3-0.6
                                     2.7-1.3        4.9-2.7
                                         Size bin (urn)
                                                             10-4.9
                                            Source: Adapted with Permission of Springer-Verlag from Gutierrez-Daban et al. (2005,155818).
Figure 3-43.    Mass distributions for 16 PAHs at a high traffic city center in Seville, Spain.
3.5.2.   Temporal Variability
      Temporal variability is another important factor in characterizing PM. This section addresses
trends as well as seasonal and hourly variability. Trends in PM2.5 and PM10 are addressed in
Section 3.5.2.1 based on AQS data. Seasonality is coupled with spatial variability and has been
discussed in the regional context above. Section 3.5.2.2 below briefly investigates the seasonality on
a finer time scale, thereby addressing issues relating to the seasonal definitions used earlier.
Section 0 addresses hourly patterns, an issue particularly important to understanding the behavior of
PM concentrations in reference to sources, human activity patterns and exposure. Hourly patterns are
investigated using AQS data on a national basis for PM2.5 and PM10. Data for UFPs and PM
constituents are presented where available.

3.5.2.1.   Regional  Trends
      This section summarizes available information on trends in PM mass and composition. Mass
concentration trends are based on AQS data and incorporate 9 years (1999-2007) of PM2.5 data and
20 years (1988-2007) of PMi0 data. Composition trends are based  on six years of available CSN data
(2002-2007). Several monitoring sites were excluded from the following trend analyses to provide a
consistent basis for comparison over the desired years of monitoring. This included exclusion of sites
when there was no corresponding site in later or earlier years. Region-average trends were calculated
to facilitate presentation and extrapolation of the results. These region-averages, however, may not
necessarily represent the trends that are being observed at any individual monitor or geographical
location within the specified region.
December 2009
3-91

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      PM2.5

      Figure 3-44 shows trends in U.S. ambient 24-h PM2.5 concentrations from 1999-2007. In the
period 2005-2007, the 3-yr avg of the 98th percentile of 24-h PM2.5 concentrations fell 10% relative
to the 1999-2001 period (see Figure 3-44A). The number of sites reporting values greater than the
24-h NAAQS was shown to decline 40% in Figure 3-44B. Figure 3-44C illustrates the downward
trend in the 98th percentile of 24-h PM2.5 concentrations for three consecutive calendar years in all
U.S. EPA regions. This trend is most pronounced in Region 9 incorporating Arizona, California and
Nevada where this value dropped 25% from the 1999-2001 period to the 2005-2007 period.
        60
           A) Ambient Concentrations
    5 t
    s-s
        45
        30
 T5 ^±:
• I»
'§
      5 15
         0
          90% of sites have
          concentrations below this line
                              NAAQS = 35 jg/m:
         10% of sites have
         concentrations below this line
        '99-'01   '00'02  '01-'03  '02-'04  '03-'05   '04-'06  '05-'07
                      Averaging period
       400
           B) Number of Trend Sites Above NAAQS
  OJ
  a,
     8300
     -  .
   i a

 Ji
ro if:
s ° Ł
'? O) —
^ a> *r
SŁ^
       200
    o J> 100
  o S
          •99-01 '00-'02 '01-'03  '02-'04 '03-'05 '04-'06 '05-'07
                      Averaging period
                                                          C) Trends by EPA Region3
                                                 II
                                                 ro -—-
                                                 IS 45
                                                 CJ d>
                                                    s.
                                                  O. Oi
                                                  fee  o
                                                                        NAAQS . 35 ug/m3
             -R1
             -R2
             -R3
             -R4
             -R5
             -R6
              R7
              R8
             -R9
             -R10
             -Nat'l
                                                      '99-'01 'OG-'02 '01-'03 '02-P04 W05 '04-'06 '05-07
                                                                   Averaging period
                                                   'Coverage: 697 monitoring sites
                                                   in the EPA Regions (out of a total
                                                   of 831 sites measuring PM2.5 in
                                                   2007) that have sufficient data to
                                                   assess PM25 trends since 1999.
   EPA Regions
 ©          O °
O        °0

                                                                              Source: U.S. EPA (2008, 157076)
Figure 3-44.   Ambient 24-h PM2.s concentrations in the U.S., 1999-2007, showing A) ambient
               concentrations, B) number of trends sites above the 24-h NAAQS and C) trends
               by U.S. EPA Region.

      Figure 3-45 contains similar trend information for the annual PM2.5 NAAQS. The seasonally
weighted 3-yr avg PM2 5 concentrations for the years 2005-2007 were at the lowest since national
monitoring began in 1999 (Figure 3-45A). The seasonally weighted 3-yr avg fell 10% between the
1999-2001 averaging period and the 2005-2007 averaging period. The number of sites reporting
concentrations above the annual average PM2 5 NAAQS fell 56% over these same periods in Figure
3-45B. Figure 3-45C illustrates the annual trends in PM25 by U.S. EPA region. Declines were the
greatest in Region 9 again where annual PM25 concentrations fell 20% from the 1999-2001
averaging period to the 2005-2007 averaging period.
December 2009
                                             3-92

-------
 S1 s
 S --e
       20
         A) Ambient Concentrations
 03 ^
 !jk
 •5 s E
           90% of sites have concentrations below this line

       _NA_A_a_S_=_1_5_ug_/nr;
            10% of sites have concentrations below this line
      •99-01  '00-'02  -01-'03  '02-'04  '03-05  '04-06  '05-'07
                  Averaging period
       300
          B) Number of Trend Sites Above NAAQS
  ,.
 "
       250
t  §
C o ^
       200
   Ł Ł 150
IP
s i'
   g
       100
                 Inn
         '99-'01 '00-'02 '01-'03 '02-'04  '03-'05 "04-'06 '05-'07
                   Averaging period
20
||
ly weighted annu;
ration for three co
lendar years (pg/r
g t 3 •
1 i
00 «
C) Trends by EPA Region3


NAAQS = 15 U
g/m3

	 -031^^1^= 	


^

-.



- - —
— _

-R1
R2
R4
R5
R6
R7
R8
-R9
-R10
— Nat'l
                                                  '99-TJ1  '00-'02 '01-'03 '02-04 '03-TJ5 '04-'06 '05-'07
                                                            Averaging period
                                            ''Coverage: 697 monitoring
                                            sites in the EPA Regions (out
                                            of a total of 802 sites
                                            measuring PMj5 in 2007) that
                                            have sufficient data to assess
                                            PM2.5 trends since 1999.
                                                                     EPA Regions


                                                                           0
                                                                             i
                                                                     Source: U.S. EPA (2008, 157076).
Figure 3-45.   Ambient annual PM2.s concentrations in the U.S., 1999-2007, showing A) ambient
             concentrations, B) number of trends sites above the annual NAAQS and C)
             trends by U.S. EPA Region.
     PM10

     Figure 3-46 shows trends in U.S. ambient 24-h PMi0 concentrations from 1988-2007. In 2007,
the U.S. national average second highest PMi0 concentration was 37% lower than in 1988 (Figure
3-46A). Of 281 sites used in this trend analysis, the number reporting concentrations above the 24-h
PMio NAAQS (150 (ig/m3) fell from 23 in 1988 to 5 in 2007 with a max of 29 in 1989 (Figure
3-46B). Figure 3-46C shows trends in the second highest 24-h PM10 concentrations broken down by
U.S. EPA region. All regions exhibit an overall decrease from 1988-2007. Largest decreases occurred
in EPA Region 10, which incorporates Washington, Oregon, Idaho and Alaska. Most of the decrease
occurred between 1988-1995.
December 2009
                                        3-93

-------
          A) Ambient Concentrations
                                  = 150pg/m3
            90% of sites have concentrations below this line
             10% of sites have
             concentrations below this line
            '90  '92  '94   '96  '98  '00
                         Year
                                  02  '04   '06
  gS   35
          B) Number of Trend Sites Above NAAQS
       20
  Ł 11 10

  55 "    5
  |i
  3S    0
 llM^i^Ul
             '90  '92 '94  '96  '98  '00  '02  '04  '06
                         Year
                                          C) Trends by EPA Region
                                           '90  '92 '94  '96 '98 '00 '02 '04 '06
                                                      Year
                                   Coverage: 274 monitoring sites
                                   in the EPA Regions (out of a total
                                   of 879 sites measuring PMio in
                                   2007) that have sufficient data to
                                   assess PM-io trends since 1988.
EPA Regions
                                                                          Source: U.S. EPA (2008, 157076).
Figure 3-46.
Ambient 24-h PMio concentrations in the U.S., 1988-2007, showing A) ambient
concentrations, B) number of trends sites above the 24-h NAAQS and C) trends
by U.S. EPA Region.
      PM Constituents

      The SANDWICH method discussed in Section 3.5.1.1 for estimating PM2.5 composition from
FRM mass measurements and CSN bulk composition measurements was used to evaluate trends in
PM2.5 constituents. Figure 3-47 includes stacked bar charts of PM2.5 composition from 2002 to 2007
stratified by region and season. The regions used in Figure 3-47 were selected based on common
aerosol characteristics including trends, seasonality, size distributions and/or composition as
described in chapter 6 of the 1996 PM AQCD (U.S. EPA, 1996, 079380) and differ from the EPA
regions used in the preceding figures. Figure 3-47 is based on 42 monitoring locations reporting
complete CSN data with 2002 being the first year with sufficient speciation data. The Southwest
region incorporating Arizona, New Mexico and parts of Texas and Oklahoma did not contain any
complete data and therefore is not represented in this analysis. Two seasons representing different
temperature ranges-cool (October-April) and warm (May-September)-were considered in the
figure since many PM2.5 components exhibit strong seasonal dependence.
December 2009
                              3-94

-------
      Cool
                        Warm
  20-
  16-
          Northwest
              20-
              16-
              12-
  20-

 fl6-

 112
 *& 8
 CO
 S 4

   0
02 03 04 05 06 07   02 03 04 05 06 07

         North Central
              20-
              16-
              12-
    I
4-
               0
      02 03 04 05 06 07    02 03 04 05 06 07
                 Midwest
20-
F 16-
112-
S 8-
CO
5 4-
n-
20-
16-
-
-
-
1
-
12-
8-
4-
n -

— I
-
_
-

-



-
m
-
                                   Cool
Warm
Northeast
20-
I16:
% 8-
TO
5 4-
n -
20-
16-
.

—

—

Dn
n
=

8:
4-

=,
.

p.
-


-

==
-


—

.

                                   02 03 04 05 06 07    02 03 04 05 06 07
                                              Southeast
                                                 20-
                                                 16-
                                                 •12-
                                                  4-
                                                     20
                                                   E~16
                                                8-
                                                4
                                                0
                                                  02 03 04 05 06 07   02 03 04 05 06 07

                                                        Southern California
                                                                20-
                                                                16-
                                                                12-
                                                                       4-
                                                                       0
      02 03 04 05 06 07    02 03 04 05 06 07
                                                        02 03 04 05 06 07
                                                                         02 03 04 05 06 07
 I    I Sulfate  I  H Nitrate

      I	I Organic Carbon
                     Elemental Carbon

                     I Crustal
                                                  Northwest
                                            North Central
                                                     Midwest
                                                                       .*.'.'*
                                                                          f,    .  Northeast
                                                Southern •                       *
                                                California     Southwest          . •   .
                                                                            •
                                                                      Southeast

                                                                       Source: U.S. EPA (2008,1911901.

Figure 3-47.   Regional and seasonal trends in annual PM2.s compostion from 2002 to 2007
              derived using the SANDWICH method. Data from the 42 monitoring locations
              shown on the map were stratified by region and season including cool months
              (October-April) and warm months (May-September). S042" and N03~ estimates
              include NH4+ and particle bound water.

      Most of the components showed little discernable trend over the 6-yr period. SO42~ showed a
peak during the warm months of 2005 in the Southeast, Northeast and Midwest, partly due to
atypical weather conditions (U.S. EPA,  2008, 191190). However, no trend over the 6-yr time period
is present for SO42~ in any of the regions or seasons. The same is true for EC and crustal material. A
slight decline in OC was observed for the Northeast during warm months and in Southern California
year-round. The largest decline was for  NO3" in Southern California during both cool and warm
December 2009
                                    3-95

-------
months. A smaller decline in NO3" is also observed in the other regions with the exception of the
Northwest where no discernible trend is present. This analysis is limited in time and space by the
availability of CSN data so a high degree of uncertainty remains regarding PM2.5 compositional
trends. However, with the exception of NO3" concentrations in Southern California, no major
changes in PM2.5 composition are evident based on available CSN data from 2002-2007. This is
consistent with Figure 3-44 and Figure 3-45 where the downward trend in PM25 mass begins to level
off after 2002.


3.5.2.2.   Seasonal Variations

      Many of the figures and tables presented in the preceding sections have included a seasonal
break-down based on the following climatological seasons: winter (December-February), spring
(March-May), summer (June-August) and fall (September-November). Figures A-142 through A-156
in Annex A show bar charts of PM2.5 composition by individual month, illustrating intra-annual
variability on a finer time scale. The same 15  CS As/CBS As are investigated and included in these
plots; they are generated from the same data used in the seasonal and annual pie charts based on the
SANDWICH method discussed in Section 3.5.1.1 and illustrated in Figure 3-17 and Figure 3-18.
      Monthly plots for most of the areas reveal heterogeneity in PM composition within the
3-month long seasonal bins defined earlier. This is especially true in the spring and fall when daily
average weather conditions (e.g., temperature) are changing most rapidly, driving fluctuation in
PM2 5 composition on relatively short timescales in many cities. For example, the NO3~ mass in Los
Angeles (Figure A-129) and Riverside (Figure A-134) can vary from a small fraction to the most
prevalent fraction of PM25 mass in a month's time based on the 3-yr aggregate data. Therefore,
selecting a different delineation point for the seasons can have an influence on the seasonal
composition analysis, specifically for constituents that fluctuate rapidly (e.g., NO3~).
      Relatively little is known about the seasonal variability in UFPs. Kuhn et al. (2005, 129448)
and Zhu et al. (2004,  156184) found that the concentrations in the UF mode in Los Angeles, CA can
be much higher during winter, particularly during evenings, because atmospheric dilution is reduced
in response to lower mixing heights (Figure 3-48). Jeong et al. (2004,  180350) made similar
observations in Rochester, NY, suggesting an inverse relationship between temperature and UFP
formation in the 11-470 nm size range. Singh et al. (2006, 190136) reported higher particle number
concentrations during winter months, relative to summer and spring, at urban sites in Southern
California, and that afternoon particle number concentrations in warm months either occurred during
a peak in ozone concentrations or followed shortly thereafter, suggesting a role for photochemistry in
addition to meteorological changes in the formation of aerosols.  The study also reported increased
concentrations of 60-200 nm particles during a labor strike at the Port of Long Beach, suggesting
contributions from idling ships. Moore et al. (2009, 191004) also report higher particle number
concentrations during cooler months at 14 sites in Long Beach, San Pedro, and Wilmington, CA, a
location with diverse industrial and transportation sources. However, they noted substantial
heterogeneity in seasonal trends between sites with seasonal numerical size distributions not
generalizable across the study area with a maximum monitor separation of under 10 km.
December 2009                                 3-96

-------



, — ,
5
"^Q.
f
§
"O



180000
160000
140000
120000
100000
80000
60000
40000
20000
n
1 ' ' ' 	


/ ''"-, Site A Summer 	 -•-
-
i. / '"-_ —
V..,'""
o^— - ^~z % v^_ x^
r"^~""r^:^?^:
                                  10
                     20
30
50
100
    25000


—  20000
'1
^  15000


M-  10000


~°   5000
                                                   Site B Winter Even. 	—
                                                    Site B Winter Day	
                                                     Site B Summer	
                                  10       20    30    50       100
                                        Particle diameter dp [nm]

                                                 Source:Reprinted with Permission of Elsevier Ltd. from Kuhn et al. (2005,1294481.

Figure 3-48.   UFP size distribution at highway (site A) and background (site B) sites in Los
              Angeles, CA, during summer and winter seasons, with winter broken into day
              and evening distributions.

      Studies reporting higher cold-season particle number concentrations are consistent with
vehicle emission studies that found particle emission rates elevated during lower ambient
temperatures (Baldauf et al., 2005, 191184: Mathis et al., 2005, 155970: U.S. EPA, 2008, 191767).
Mathis et al. (2005, 155970) found that cold-start conditions produce roughly an order of magnitude
greater PM number emissions in gasoline engines and more than two orders  of magnitude higher PM
number emissions in diesel engines when compared with warm start conditions.


3.5.2.3.   Hourly Variability

      Hourly PM2.5 and PMi0 measurements are conducted at many sites using beta gauge or TEOM
monitors. Many of the hourly measurements for PM10 have FRM or FEM status. All available hourly
data from FRM, FEM and FRM-like monitors in the 15 CS As/CBS As discussed earlier were used to
investigate diel variation in PM. Of the 15 CS As/CBS As, Atlanta, Chicago, Pittsburgh, Seattle and
St. Louis had qualifying hourly PM2 5 and PMi0 data available. Houston and  New York had only
qualifying PM2.5 data. Denver, Detroit, Los Angeles, Philadelphia, Phoenix, and Riverside had only
qualifying hourly PMi0 data. Birmingham and Boston had no qualifying hourly PM2.5 or PMi0 data.
      Diel plots for PM25 stratified by weekdays and weekends for seven of the 15 CS As/CBS As
with available data between 2005 and 2007 are included in Annex A, Figures A-157 through A-163.
In most cities investigated, a morning PM25 peak is present starting at approximately 6:00 a.m.,
corresponding with the start of the morning rush hour just before the break-up of overnight
stagnation. In Pittsburgh, dispersion behavior during the night results in elevated PM2 5
December 2009
                       3-97

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concentrations throughout the night that blend in with any morning peak. With the exception of
Pittsburgh, all seven metropolitan areas show two distinct daily peaks on both the weekdays and
weekends. The evening PM2.5 concentration peak is broader than the morning peak and extends to
overnight hours, reflecting the concentration increase caused by a drop in boundary layer height at
night. Figure 3-49 compares the two-peak diel distribution in PM2.s for Seattle with the one-peak
distribution in PM2.5 for Pittsburgh Since these figures represent the distribution of hourly
observations over a 3-yr period, any fluctuations or changes in the timing of the daily peaks would
result in a broadening of the curves shown in the diel plot.
                                  Pittsburgh
               Weekday (N = 981)
                                          Weekend (N = 407)
    en
       77 -i
58 -
       38 -
       19 -
                                  77 -i
                                         58 -
                                  38 -
                                  19 -
                                                                               • Median
                                  	Mean

                                  	90th & 10th

                                  	95th & 5th
                      12     18     24
                                                 12     18     24
                                    Seattle
               Weekday (N = 5775)
                                          Weekend (N = 2332)
    Ł

    O)
    LO
    c\i
   ^
   CL
       77 i
       58 -
       38 -
19 -
77 -i


58


38


19 -
                                                                               • Median
                                                                    	Mean

                                                                    	90th & 10th

                                                                    	95th & 5th
                      12     18     24
                                                 12     18     24
Figure 3-49.   Diel plot generated from hourly FRM-like PM2s data (iig/m3) stratified by weekday
              (left) and weekend (right) for Pittsburgh, PA, and Seattle, WA, 2005-2007.
              Included are the number of monitor days (N) and the median, mean, 5th, 10th,
              90th and 95th percentiles for each hour of the day shown on the horizontal axis.
December 2009
                                     3-9

-------
      Annex A, Figures A-164 through A-174 show diel patterns for PM10 stratified by weekdays
and weekends for eleven of the 15 CSAs/CBSAs with available data between 2005 and 2007. All
cities show a gradual morning increase in mean PMi0 starting at approximately 6:00 a.m. on
weekdays, corresponding with the start of the morning rush hour before the break-up of overnight
stagnation. The magnitude and duration of this peak, however, varies considerably by area. Phoenix
shows the most pronounced morning PMi0 peak concentration, which drops off during the day and
reappears in the evening. In contrast, Chicago shows a less pronounced peak with the PM10
concentration remaining elevated throughout the day. Figure 3-50 shows the diel  plots of PMi0 for
Chicago and Phoenix. In both instances, the weekend diel pattern is similar in shape to the weekday
pattern with less pronounced peaks.  Once again, any fluctuations in the timing of the daily peaks
could result in a broadening of the peaks in the 3-yr composite diel figures.
                                     Chicago
                    Weekday (N = 1971)
   291 -


   218 -


   145 -


    73-
                                         291 -


                                         218 -


                                         145


                                          73
       Weekend (N = 793)
                             	Median

                             	Mean

                             	 90th & 1Oth

                             	 95th & 5th
                1
                          12    18    24
                                                      12    18    24
                                     Phoenix
                    Weekday (N = 1532)
       Weekend JN = 618)
             291 -,
"E 21S "
   145 -
          Ł  73-
291 -i


218 -


145


 73
                          12    18    24
                                                                      	Median

                                                                      	Mean

                                                                      	 90th & 1Oth

                                                                      	 95th & 5th
                                                      12    18    24
Figure 3-50.   Diel plots generated from hourly FEM PMi0 data (ng/m3) stratified by weekday
              (left) and weekend (right) for Chicago, IL, and Phoenix, AZ, 2005-2007. Included
              are the number of monitor days (N) and the median, mean, 5th, 10th, 90th and
              95th percentiles for each hour of the day shown on the horizontal axis.

      UFPs in urban environments have been shown to exhibit a similar two-peaked diel pattern in
Los Angeles (Moore et al, 2007, 122445; Sardar et al., 2005, 180086) and the San Joaquin Valley
(Herner et al., 2005, 135983) in CA, Rochester, NY (Jeong et al., 2004, 180350). Raleigh, NC
(Baldauf et al., 2008, 190239) as well as in Kawasaki City, Japan (Hasegawa et al., 2005, 157355)
and Copenhagen, Denmark (Ketzel et al., 2003, 131251). Figure 3-51 from the Denmark study
December 2009
   3-99

-------
shows a large peak in total particle number (dominated by UFPs) corresponding with the morning
rush hour. The morning peak is absent on Sundays, however. Many studies also show a broad
afternoon UFP concentration peak, which likely originates from a combination of evening rush-hour
traffic, decreased atmospheric dilution and formation of UFPs through nucleation involving products
of active photochemistry. Nucleation likely plays an important role since the afternoon peak is
present on weekends whereas the morning traffic related peak is absent. This is consistent with
observations of particle counts in Atlanta peaking during the mid-afternoon for particles <10 nm
(Woo et al., 2001, 011702) resulting from nucleation.
                     Weekdays
                                                     Sundays
    4CODO

    35C-D3

    30000

    26CDO

    20000

    •ŁCDO

    • 0000

    5CDO

       •3
  r*,
                      -Jagtv
_i	k.
                                 lOOQO
                                            Source: Adapted with Permission of Elsevier Science Ltd. From Ketzel et al. (2003,1312511

Figure 3-51.   Average diel variation in total particle number (ToN) and total particle volume
              (ToV) on weekdays (left column) and Sundays (right column) from two sites in
              Denmark: one in a busy street canyon (Jagtv) and one measuring urban
              background (HC0).

      Hourly variability in particle-phase OC and EC were investigated by Bae et al. (2004, 156243)
in the urban St. Louis atmosphere. OC diel patterns were similar during weekdays and weekends
with a broad morning and evening concentration peak most likely reflecting daily fluctuations in
atmospheric mixing height. Weekend EC diel patterns were similar to those for OC, but the weekday
patterns showed more abrupt EC concentration peaks in the morning and afternoon, coinciding with
rush-hour traffic. The divergent weekday patterns  between OC and EC suggests motor vehicles or
other EC sources with temporal profiles tracking traffic patterns are primarily responsible for the
daily fluctuations in EC concentrations in St. Louis.


3.5.3.   Statistical Associations with  Copollutants
      Associations between different PM size fractions and between PM  and other copollutants
including SO2, NO2, CO and O3  are investigated in this section. AQS data were obtained from all
available co-located monitors across the U.S.  after application of a completeness  criterion of 11 or
December 2009
                            3-100

-------
more observations per quarter. Pearson correlation coefficients (r) were calculated using 2005-2007
data. The results are displayed graphically in Figure 3-52 for correlations with PM2.5 mass
concentration and Figure 3-53 for correlations with PMi0 mass concentration. The different PM size
fractions are compared and contrasted in this section using temporal correlations which should not
be confused with average PM mass fraction (e.g., PM2.5/PMi0) comparisons discussed in
Section 3.5.1.1.
                                    Winter
                          Spring
         PM10 (daily avg) -

       PM10.25 (daily avg) -

          SO2 (daily avg) -

          NO2 (daily avg) -

          CO (daily avg) -

       O3 (daily max 8-h) -
                     -1.0-0.8-0.6-0.4-0.2 0.0 0.2 0.4 0.6 0.8 1.0   -1.0-0.8-0.6-0.4-0.2 0.0 0.2 0.4 0.6  0.8 1.0

                                    Summer                                 Fall
         PM10 (daily avg) -

       PM10.2.6 (daily avg)  -

          SO2 (daily avg) -

          NO2 (daily avg) -

          CO (daily avg) -

        O3 (daily max 8-h) -
                     -1.0-0.8-0.6-0.4-0.2 0.0 0.2 0.4  0.6 0.8 1.0   -1.0-0.8-0.6-0.4-0.2 0.0 0.2 0.4 0.6  0.8 1.0

                          correlation (r) with PM25 (daily avg)              correlation (r) with PM25 (daily avg)
Figure 3-52.    Distribution of correlations between 24-h avg PM2.s and co-located 24-h avg
                PMio-2.6, S02, N02 and CO and daily max 8-h avg 03 for the U.S. stratified by
                season (2005-2007). Statistics shown include the mean (green star), median (red
                line), inner quartile range (box), 5th/95th percentiles (whiskers) and outliers
                (black circles).
December 2009
3-101

-------
                                  Winter
                        Spring
        PM25 (daily avg) -

       PM10.25 (daily avg) -

         SO2 (daily avg) -

         NO2 (daily avg) -

          CO (daily avg) -

       O3 (daily max 8-h) -
                    -1.0-0.8-0.6-0.4-0.2 0.0 0.2 0.4 0.6 0.8  1.0  -1.0-0.8-0.6-0.4-0.2 0.0 0.2 0.4  0.6 0.8 1.0

                                 Summer                              Fall
        PM25 (daily avg) -

       PM10.25 (daily avg) -

         SO2 (daily avg) -

         NO2 (daily avg) -

          CO (daily avg) -

       O3 (daily max 8-h) -
                    -1.0-0.8-0.6-0.4-0.2 0.0 0.2 0.4 0.6 0.8  1.0  -1.0-0.8-0.6-0.4-0.2 0.0 0.2 0.4  0.6 0.8 1.0

                       correlation (r) with PM10 (daily avg)         correlation (r) with PM10 (daily avg)
Figure 3-53.    Distribution of correlations between 24-h avg PMi0 and co-located 24-h avg PM2.6,
               PMio-2.6, S02, N02 and CO and daily max 8-h avg 63 for the U.S. stratified by
               season (2005-2007). Statistics shown include the mean (green star), median (red
               line), inner quartile range (box), 5th/95th percentiles (whiskers) and outliers
               (black circles).

      For both PM2.5 and PMi0 national composite copollutant correlations, there is considerable
spread in the observed correlations in all four seasons. On average, PM2.5 and PMi0 correlate with
each other better than with the gaseous copollutants. The correlations between PM2.5 and PM10 are all
positive but span the range from just above zero to near one. This illustrates the wide variability in
correlation between these two PM metrics. Fewer points are available for correlation with PMi0_2.5
because only data from low-volume FRM/FRM-like samplers were used to calculate PMi0_2.5. The
available data suggest a stronger correlation between PMi0 and PMi0_2.5 than between PM2.5 and
PMio_2.5 on a national basis.
      Correlations among copollutants for individual CSAs/CBSAs are included in Annex A,
Figure A-175 through Figure A-188 for PM2.5 and Figure A-189 through Figure A-202 for PM10.
Each data point in these figures represents a co-located monitor pair. Seattle did not have sufficient
co-located data to be included with the other CSAs/CBSAs.  As can be seen from the individual
CSAs/CBSAs, there can be considerable variation in the correlations even  within an individual urban
area.  For example, correlations between 24-h average PM2.5 and PMi0 concentrations measured at
the five co-located monitor pairs in Boston between 2005 and 2007 ranged from 0.42 to 0.88 during
winter and reach as high as 0.98 during the summer (Figure A-177).
      Few locations within the 15 CSAs/CBSAs contained adequate data for calculating correlations
with PMio_2.s using low-volume PM data:  Boston and New York had two locations each, Atlanta,
Chicago, Denver and Phoenix had only one location and the remaining CSAs/CBSAs had no
locations. Correlations between PM2 5  and PMi0_2.5 varied substantially by  CSA/CBSA and season
and no general patterns were observed  in the limited data set analyzed here. In contrast, correlations
between PMi0 and PM10_2.5 did show some trends by location and season and were greater in all
locations than correlations  between PM2 5 and PMi0_2.5.  The highest correlations between PMi0 and
December 2009
3-102

-------
PM10_2.5 were observed in Denver and Phoenix with correlations above 0.88 during all seasons.
Atlanta, Boston, Chicago and New York all had lower correlations between PMi0 and PMi0_2.s
(0.30< r <0.88), particularly during the fall (0.30< r <0.56).  The lowest correlations between PMi0
and PMio_2.5 were observed in New York in the fall and Boston in the summer where they dropped to
0.30 and 0.38, respectively, at one of the two monitor locations in each city. In the four eastern
CSAs/CBSAs investigated, correlations between PMi0 and PMi0_2.5 were highest in the spring, in
agreement with the national averages shown in Figure 3-53. In Denver and Phoenix, there was less
seasonal dependence in the correlation.
      A similar analysis of correlations between PM size fractions by region was reported in Table
3-1 of the 2004 PM AQCD (U.S. EPA, 2004, 056905) and Figure 2-20 of the 2005 OAQPS Staff
Paper (U.S. EPA, 2005, 090209). In all regions, correlations between PMi0 and PMi0_2.5 were greater
than those for PM2.5 and PMi0_2.5. Correlations between PMi0 and PMi0_2.5 were found to be largest
in the southwest and the upper Midwest and smallest in the southeast and the northeast. While these
regional analyses used different data inclusion criteria for estimating PMi0_2.5 than the criteria used in
this analysis for the individual CSAs/CBSAs, the results are generally consistent:  higher
correlations between PMi0 and PMi0_2.5 mass concentrations compared with PM2.5 and PMi0_2.5 mass
concentrations in all regions and higher correlations between PMi0 and PMi0_2.5 mass concentrations
in the west compared to the east.
      The correlation between PM and the gaseous pollutants included in Figure 3-52 and Figure
3-53 also showed a large range in values based on the national composite data. There was little
seasonal variability in the mean correlation between PM and SO2. NO2 and CO, however, showed
higher correlations with PM on average in winter than in the other seasons. This is possibly driven
by meteorology with increased frequency of stagnation events in colder months  as well as potential
concurrent increases in emissions of these compounds from motor vehicles with colder temperatures.
The correlation between daily max 8-h avg O3 and 24-h avg PM showed the highest degree of
seasonal variability with positive correlations on average in summer (0.56 for PM2.5 and 0.39 for
PMio) and negative correlations on average in winter (-0.30 for PM2.s and -0.18 for PMi0). During
the transition seasons, spring and fall, correlations were mixed but on average were still positive.
PM2.5 is both primary and secondary in origin, whereas O3 is only secondary.  Photochemical
production of O3 and secondary PM in the planetary boundary layer (PBL) is much slower during
the winter than during other seasons. Primary pollutant concentrations (e.g., primary PM2.5
components, NO and NO2) in many urban areas are elevated in winter as the result of heating
emissions, cold starts and low mixing heights. O3 in the PBL during winter is mainly associated with
air subsiding from above the boundary layer following the passage of cold fronts, and this subsiding
air has much  lower PM concentrations than are present in the PBL. Therefore, a negative association
between O3 and PM is frequently observed in the winter. During summer, both O3 and secondary
PM2.5 are produced in the PBL and in the lower free troposphere at faster rates compared to winter,
and so they tend to be positively correlated. Bell et al. (2007, 093256) also observed wintertime
minima in same-day correlations between 24-h avg PM (both PM2.5 and PMio) and 24-h avg O3
using data from 98 U.S. urban communities. The average correlations were positive in winter, unlike
those shown in Figure 3-53. Furthermore, the highest national average correlations were in spring
and fall in the Bell et al.  (2007, 093256) analysis rather than summer as observed in Figure 3-52 and
Figure 3-53. This discrepancy could be a result of the different averaging times used for O3 or the
selection of different monitoring networks and/or time periods.
      For the PM2.5 city-specific correlations shown in Annex A, Figure A-175 through Figure A-
188, all selected cities with sufficient data showed negative correlations in the wintertime with daily
max 8-h avg O3 (including Birmingham, Boston, Chicago, Denver, Houston, Los Angeles,
Philadelphia, Phoenix, Pittsburgh, Riverside and St. Louis).  The remaining four CSAs/CBSAs had
insufficient data. In Baltimore, Sarnat et al. (2001, 019401) found a significant (at the p <0.05 level)
positive (0.67) and negative (-0.72) correlation between daily PM25 and O3 in the summer (June
19-August 23, 1998) and winter (February 2-March 13, 1999), respectively. For PMi0, the city-
specific correlations with max 8-h avg O3 shown in Annex A, Figure A-189 through Figure A-202
were more variable. Birmingham, Boston, and St. Louis all showed positive wintertime correlations
between PMio and daily  maximum 8-h avg O3 while Denver, Detroit, Houston, Los Angeles  and
Phoenix showed negative wintertime correlations. The remaining seven CSAs/CBSAs had
insufficient data. These copollutant correlations illustrate the importance of considering seasonality
when assessing temporal relationships between air pollutants, particularly PM and O3.
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3.6.  Mathematical  Modeling  of PM
      There are two main classes of models used to study atmospheric PM, receptor models and
CTMs. Receptor models are statistical models whereas CTMs are numerical models, i.e., they
approximate derivatives by finite difference approximations. Finite element models are also
numerical models but have not been used as extensively for applications described here, and so are
not discussed further.  Receptor models are diagnostic in their approach, in that they try to derive
source contributions at monitoring locations using either ambient data alone or in combination with
data for the chemical composition of sources or in combination with meteorological data. Three-
dimensional CTMs are formulated in a prognostic, or predictive manner, that is, they attempt to
predict species concentrations by solving a set of coupled, non-linear partial differential equations
(continuity  equations) for chemical species that include terms based on emissions inventories,
atmospheric transport, chemical transformations, and deposition. Monitoring data is used to evaluate
the performance of CTMs. Each of these approaches has its own advantages and disadvantages.


3.6.1.   Estimating  Source Contributions to PM Using  Receptor Models

      Methods for analyzing the composition of ambient PM samples in terms of contributions from
different sources are reviewed in this section.  Associations between exposures to ambient PM, as
represented by ambient monitors, and health outcomes have been extensively studied.  Some health
studies, described in Section 6.6, have used source apportionment modeling to evaluate relationships
between health outcomes and PM (mainly PM2.5) from different sources. This section is intended to
provide background concerning the uses of source apportionment techniques in such studies.
Understanding the contribution of different emissions sources to ambient PM has also  been used
extensively in evaluating air quality data for use in developing control strategies.


3.6.1.1.  Receptor  Models

      Receptor models have been used mainly as part of the development of air quality management
plans. However, there have been several publications relating apportioned source types based on
receptor models to human health effects. Discussions in this section will focus mainly  on those
methods that have been used to relate health outcomes to sources. More complete descriptions of a
large number of types of receptor models currently in use are given in Watson et al. (2008,  157128).
who summarize the properties of these methods, including the strengths and weaknesses. This
compilation of receptor models, broken down into different approaches (i.e., chemical  mass balance,
factor analysis, tracer-based, meteorology based) is included in Tables A-51 through A-54 in
Annex A.
      Receptor models such as the  chemical mass balance (CMB) model (Watson et al., 1990,
004848) relate source category contributions to ambient PM concentrations based on analyses of the
compositional profiles of ambient and source  emissions samples. It uses as its basis a mass balance
equation that represents all  chemical species in an aerosol sample as linear combinations of
contributions from a fixed number of independent sources plus an error term representing the portion
of the measurement that cannot be fit by the model.
      The compositional profiles used in receptor models can be extensive (see for example the
SPECIATE data base, http://www.epa.gov/ttnchiel/software/speciate/index.html) for a
comprehensive collection of results from a large number of studies. As an example, several studies
have identified EC and over 100 organic carbon compounds in gasoline PM emissions, including
alkanes, PAHs, oxy-PAHs, steranes, hopanes, and organic acids (Maricq, 2007,  155973; Schauer et
al., 1999, 010582; Schauer  et al., 2002,  035332). This breakdown in identifiable groups of organic
compounds is illustrated in Figure 3-54 and Table 3-17 shows emissions factors for trace elements.
Data for the compositional profiles  for several other important sources of PM that could be used for
CMB modeling are shown in Table A-55 in Annex A.
      Source categories are amenable to refinement and to analysis as information  on tracers
becomes available.  For example, PBAP have long been known to be significant constituents of the
atmospheric aerosol, but not many studies have evaluated their contributions, largely because of the
lack of suitable tracers and the  additional equipment needs for sampling and analysis of bioaerosols.
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Bauer et al. (2008, 189986) reviewed studies estimating the contribution of fungal spores to PM2.5
and PM 10-2.5 as fungal spores were expected to be major contributors to PBAP. They proposed the
use of arabitol and mannitol as unique tracers with an estimated accuracy of ± 50% to apportion the
contribution of fungal spores to OC in both PM2.s and PMi0_2.5. They estimated 24-h avg
contributions of- 40% to OC in PMi0_2.5 during spring and summer in Vienna, with a smaller
contribution to PM2.s.
Fine Organic Extractable and
Compounds Editable
142mg/l
Not Extractable
or Elutable
Extractable
and Elutable
/
11 8 mg/l
Unresolved
Resolved
                                              Resolved
                                              Organics
                                               18mg/l
                                              Identified
                                              Organics
                                               5 mg/l
                                                                     -Oxy-PAH
                                                                     s Steranes
                                                                     ~~ Hopanes
Figure 3-54.
                              Source: Reprinted with Permission of Elsevier Science Ltd. From Fraser et al. (1999, 0108191

Schematic of organic composition of participate emissions from gasoline-fueled
vehicles.
      One recently-identified concern in the application of CMB-based receptor models with
detailed organic marker compounds is the photochemical stability of those species. Robinson et al.
(2006, 156918) reported evidence of significant summertime photooxidation of hopanes and long-
chain alkenoic acids, low-volatility compounds often used as mobile source and cooking emissions,
respectively. Seasonal differences in hopanes/EC ratios differed in a manner consistent with
oxidation. Photochemical loss of particle-phase marker species mass complicates the interpretation
of model results, as long-range transport and photochemistry may result in the loss of markers for
distant sources. Furthermore, photochemical breakdown of organic marker species may cause losses
in CMB model performance criteria and possible bias in source contribution estimates. The
photooxidation of condensed-phase organic compounds also may affect the polarity and volatility of
these compounds.
      In other methods, various forms of factor analysis are used that rely on the varying mix of
species present in ambient observations of compositional data to derive the source contributions.
Standard factor analytic approaches such as Principal Component Analysis (PCA) have been  used,
but PCA alone can apportion only the variance, not the mass, in an aerosol composition data set.
Additional steps in particular the identification of source tracers is required in Absolute Principal
Components Scores (APCS) to apportion mass from PCA (Miller et al., 2002, 030661; Thurston and
Spengler, 1985, 056074). However, it can be difficult to find suitable tracers for some sources
because many elements are emitted by more than one source. In Positive Matrix Factorization (PMF)
(Paatero  and Tapper, 1994, 086998). the ambient compositional data matrix is decomposed into the
product of a matrix representing the source contributions and one representing the source profiles.
Solutions are obtained by minimizing an object function with respect to these two matrices, and
solutions are subject to non-negativity constraints. PMF also allows for the treatment of missing data
and data near or below detection limits by weighting elements inversely according to their
uncertainties. The PMF approach requires a large number of samples (n typically >50) and are most
often applied to time series data, whereas CMB can be applied to a single sample. Both the CMB
and the PMF  approaches find solutions based on least squares fitting and minimization of an  object
function. Both methods provide error estimates for the solutions based on estimates of the  errors in
the  input parameters. It should be noted, though, that the error estimates for both methods often
contain subjective judgments about the magnitude of the analytical and monitoring errors.
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Table 3-17.   Example of emissions factors (ng/km) for trace elements under variable speed and
             steady speed driving conditions for PM emitted by diesel and gasoline engines. Note
             that emissions are highly variable.
                             Diesel
                         Gasoline

Al
Ca
Fe
K
Mg
Na
Ba
Be
Cr
Cu
Li
Mn
Ni
Pb
S
Ti
V
Zn
Transient
9108 (5224)
69,443 (23,640)
22,910(21,448)
4672 (752)
3087 (461
7736(1751)
583 (349)
26(12)
634 (354)
1944(679)
13 (0.2)
368(183)
2310(656)
793 (593)
23,750 (5295)
2036 (320)
28 (9.4)
21,118(4422)
Steady State
2706
16,128
2036
1191
997
1945
73
23
93
627
7.9
76
644
79
6713
345
11
5620
Transient
2273 (545)
18,247(3044)
10,266(9928)
1935(558)
5183(1706)
2237(1125)
331 (55)
6.7(1.1)
138 (6.7)
1745(1803)
3.0(1.4)
152(85)
107 (0.7)
237 (2.3)
8705 (3375)
118(9.3)
15(11)
4650(1225)
Steady State
252
2324
138
117
183
321
4.8
1.5
8.6
16
0.9
3.4
21
11
349
24
1.8
198
Standard deviations are presented in parenthesis when multiple tests have been averaged.
                                                  Source: Adapted with Permission of Elsevier Ltd. from Geller et al. (2006,1396441
      The nature of the solutions in terms of source categories is different in the CMB and PMF
approaches. In the CMB approach, the composition of the source emissions is assumed to be known
based on measurements. These assumptions may or may not reflect the composition of emissions
affecting a particular site at any given time or place. However, there may be variations in the
composition of individual source categories (e.g., soils,  motor vehicle emissions) across  a given
airshed and even in the composition of the same source  with time. Source profiles can also be altered
between emission and receptor locations resulting from  atmospheric reactions, depending on the
source type and species under analysis. The CMB technique was developed for apportioning source
categories of primary PM and was not formulated to include sources of secondary PM. CMB might
not explain all the mass or produce a valid result unless  there is information for the composition of
all major sources affecting a given site, and there is confidence that the existing source profiles are
specific to those sources. For example, Volckens et al. (2008, 105465) describe PAH emission
profiles from hand-held gasoline lawn and garden equipment as found in some CMB source profiles
for motor vehicles.
      In PMF, the source solutions are more general in that they contain information about the
entrainment of emissions from additional sources during transport, the time dependence  of the
composition of emissions from particular sources, the formation of secondary species and local
differences in source compositions. PMF differs from CMB because it derives  the mix of factors
from measured data. However, the procedure used to find a solution results in some rotational
ambiguity (Paatero  and Tapper, 1994, 086998). The assignment of sources to PMF factors depends
largely on past experience and judgments. Judgments  are based to large extent on comparison with
data for source profiles and also on the factors that could modify the assignments. These issues are
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alleviated to some degree by incorporating information about local wind fields and other physical
parameters.
      The UNMIX model takes a geometric approach that exploits the covariance of the ambient
data to determine the number of independent sources, the composition and contributions of the
sources, and corresponding uncertainties (Henry, 1997, 020941). UNMIX uses PC A to find edges in
m-dimensional space, where m is the number of ambient species. Success of the UNMIX model
hinges on the ability to find these "edges" in the ambient data from which the number of source
types  and the source compositions are extracted. In simplest terms, the approach can be seen to be
similar to that for deriving ternary mixing diagrams, except there is extension to higher
dimensionality. Measurement errors in the ambient data "fuzz" the edges, making them difficult to
find. UNMIX employs an "edge-finding" algorithm to find the best edges in the presence of error.
UNMIX does not make explicit use of errors or uncertainties in the ambient concentrations, unlike
the methods outlined above. Rather they are implicitly incorporated into the analyses. PMF and
UNMIX have also used data for particle size distributions to obtain further information about
sources.
      Partial least squares (PLS) is another  mathematical model related to PCA which has been used
in a limited number of PM toxicology studies to establish a relationship between PM constituents
and health outcomes (McDonald et al., 2004, 087458: Seagrave et al, 2006, 091291: Veranth et al.,
2006,  087479). Although not really  a receptor model and not designed as such, PLS shares some
similarities with certain receptor models; and more importantly attempts to link PM components
with health outcomes. Unlike PCA and other receptor models discussed in this section, PLS
incorporates both predictor variables (e.g., PM component concentrations) and outcome variables
(e.g., toxicological responses) into one coupled regression model. Like PCA, PLS groups the
observable variables into a reduced number of latent variables, thereby reducing the dimensionality
of the model. Typically, PM toxicology studies have been limited to two-component models (two
latent  variables on the predictor side compared with two on the  outcome side), thereby producing a
2x2 loading plot revealing relationships between predictors and outcomes. PLS is particularly useful
when  there are more predictor variables than observations, which is a situation that other
multivariate factor analysis approaches do not handle well. However, since PLS  is a variance based
approach, it shares the same shortcomings discussed earlier for  PCA. PLS has also traditionally been
limited to two-component applications even though this is not a strict mathematical limitation.


      Results from Receptor Models

      Results from receptor modeling calculations indicate that PM2.5 is  most often produced mainly
by fossil fuel combustion. Fugitive dust, found mainly in the PM10_2.5 size range, represents the
largest source of measured ambient  PMi0 in many locations in the western U.S. Quoted uncertainties
in the source apportionment of constituents  in ambient aerosol samples typically range from 10 to
50%.  It is apparent that  a relatively small number of broadly defined  source categories, compared to
the total number of chemical species that typically are measured in ambient monitoring-source
receptor model studies,  are needed to account for the majority of the observed mass of PM in these
studies. Trying to be more specific about contributions from source categories could result in
ambiguity. For example, some stationary sources (e.g., agriculture use engines) and quite different
mobile sources (e.g., trucks and locomotives) rely on diesel power and ancillary data is required to
resolve contributions from these sources. Compilations of source attribution studies using CMB for
PMi0  have appeared in the 2004 PM AQCD (U.S. EPA, 2004, 056905) and using PMF for PM2 5 in
Engel-Cox and Weber (2007, 156419). Results of the compilation by Engel-Cox and Weber (2007,
156419) for the eastern  U.S. are shown in Figure 3-53. There are only three main source categories
in the figure constituting most of the PM2.5 mass (i.e., sulfate, nitrate, mobile). Two of these are
predominantly secondary and not identified by sources of precursors. Tables A-56 and A-57 in
Annex A list results of other receptor modeling studies for PM2 5 and  PMi0, many of which are in the
western U.S.
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                    TOTAL   Sulfitc
                                            Mobile    Lu

                                               Source
                                                           Industrial  CrustaktSalt   Othc
                               Source: Reprinted with Permission of Air & Waste Management Association from Engel-Cox and Weber (2007, 156419).

Figure 3-55.    Source category contributions to PM2.s  at a number of sites in the East derived
               using PMF.
      Spatial Variability in Source Contributions to PM Based on Receptor Models

      Spatial variability in source contributions across urban areas is an important consideration in
assessing the likelihood of exposure measurement error in epidemiologic studies relating health
endpoints to sources. Arguments similar to those for using ambient concentrations as surrogates for
personal exposures apply here. Studies for PM2.5 (Kim et al., 2005, 083181; Wongphatarakul et al.,
1998, 049281) indicate that intra-urban variability increases in the following order: regional sources
(e.g., secondary SO42~ originating from EGUs) < area sources (e.g., on-road mobile sources) < point
sources (e.g., stacks). This  point is illustrated in Figure 3-56. The only study available for PMi0_2.5
(Hwang et al., 2008, 134420) indicates a similar ordering, but without a regional component
(resulting from the short lifetime of coarse PM compared to transport times on the regional scale) as
shown in Figure 3-57.
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                          0.2
                          0.0
                          -0.2
                             Sec. -
                                                      Source: Reprinted with Permission of ACS from Kim et al. (2005, 083181)
Figure 3-56.   Pearson correlation coefficients for source category contributions to PM2.s
              between the 10 Regional Air Pollution Study/Regional Air Monitoring System
              (RAPS/RAMS) monitoring sites in St. Louis.
                        .c
                        JS 0.2
                                                    Source: Reprinted with Permission of ACS from Hwang et al. (2008,1945331
Figure 3-57.   Pearson correlation coefficients for source contributions to PMi0.2.s between the
              10 Regional Air Pollution Study/Regional Air Monitoring System (RAPS/RAMS)
              monitoring sites in St. Louis.
3.6.2.   Chemistry Transport Models

      CTMs are the prime tools used to compute the interactions among atmospheric pollutants and
their transformation products, the production of secondary aerosols, the evolution of particle size
distribution, and transport and deposition of pollutants. CTMs are driven by emissions inventories
for primary species such as NOX, SOX, NH3, VOCs, and primary PM, and by meteorological fields
produced by other numerical prediction models. Values for meteorological state variables such as
winds and temperatures are taken from operational analyses, reanalyses, or weather circulation
models. In most cases, these are off-line meteorological analyses, meaning that they are not modified
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by radiatively active species generated by the air quality model (AQM). Work to integrate
meteorology and chemistry was done in the mid-1990s by Lu et al. (1997, 048202 and references
therein; 1997, 191768) although limits to computing power prevented their wide-spread application.
More recently, new, integrated models of meteorology and chemistry are now available as well; see,
for example, Binkowski et al. (2007, 090563) and the Weather Research and Forecast model with
chemistry (WRF-Chem) (http://ruc.fsl.noaa.gov/wrf/WGll).
      CTMs have been developed for application over a wide range of spatial scales ranging up from
neighborhood to global. CTMs are used to: (1) obtain better understanding of the processes
controlling the formation, transport, and destruction of gas- and particle-phase criteria and hazardous
air pollutants; (2) understand the relations between concentrations of secondary pollutant products
and concentrations of their precursors; (3) understand relations among the concentration patterns of
various pollutants that may exert adverse effects; and (4) evaluate how changes in emissions
propagate through the atmospheric system to secondary products and deposition.
      Emissions of precursor compounds  can be divided into anthropogenic and natural source
categories. Natural sources can be further divided into biogenic from vegetation, microbes, and
animals, and abiotic from biomass burning, lightning, and geogenic sources. However, the
distinction between natural sources and anthropogenic sources is often difficult to make in practice,
as human activities affect directly  or indirectly emissions from what would have been considered
natural sources during the preindustrial era. Thus, emissions from plants and animals used in
agriculture have been referred to as anthropogenic or biogenic in different applications. Wildfire
emissions may be considered natural, except that forest management practices can lead to buildup of
fuels on the forest floor, thereby altering the frequency and severity of forest fires.
      The initial conditions, or starting concentration fields of all species computed by a model, and
the boundary conditions, or concentrations of species along the horizontal and upper boundaries of
the model domain throughout the simulation, must be specified at the beginning of the simulation.
Both initial and boundary conditions can be estimated from models or data or, more generally, model
+ data hybrids. Because data for vertical profiles of most species of interest are very  sparse, results
of model simulations over larger, usually global, domains are often used. As might be expected, the
influence of boundary conditions depends on the lifetime of the species under consideration and the
time scales for transport from the boundaries to the interior of the model.
      Each of the model components described above has associated uncertainties and the relative
importance of these uncertainties varies with the modeling application. The largest errors in
photochemical modeling are still thought to arise from the meteorological and emissions inputs to
the model (Russell and Dennis, 2000, 035563). While the effects of poorly specified boundary
conditions propagate through the model's domain, the effects of these errors remain undetermined.
Because many meteorological processes occur on spatial scales smaller than the model's vertical or
horizontal grid spacing and thus are not calculated explicitly, parameterizations of these processes
must be used. These parameterizations introduce additional uncertainty. Because the chemical
production and loss terms in the continuity equations for individual species are numerically coupled,
the chemical calculations must be  performed iteratively until calculated concentrations converge to
within some preset criterion. The number  of iterations and the convergence criteria chosen also can
introduce error.
      CTMs in current use mostly have one of two forms. The first, grid-based or Eulerian air
quality models subdivide the region to be  modeled, the modeling domain, into a three-dimensional
array  of grid cells. Spatial derivatives in the species continuity equations are cast in finite-difference
form over this grid and a system of equations for the concentrations of all the chemical species in the
model are solved numerically at each grid point. Time-dependent continuity or mass conservation
equations are solved for each species  including terms for transport, chemical production and
destruction, and emissions and deposition (if relevant), in each grid cell. Chemical processes are
simulated with ordinary differential equations, and transport processes are simulated with partial
differential equations. Because of a number of factors such as the different time scales inherent in
different processes, the coupled, nonlinear nature of the chemical process terms, and computer
storage limitations, not all  of the terms in the equations are solved simultaneously in three
dimensions. Instead, operator splitting, in which terms in the continuity equation involving
individual processes are solved sequentially, is used.
      In the second common CTM formulation, trajectory or Lagrangian models, a number of
hypothetical air parcels are specified as though following wind trajectories. In these models, the
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original system of partial differential equations is transformed into a system of ordinary differential
equations.
      A less common approach is to use a hybrid Lagrangian-Eulerian model, in which certain
aspects of atmospheric chemistry and transport are treated with a Lagrangian approach and others
are treaded in an Eulerian manner (e.g., Stein et al., 2000, 048341).
      Each approach has advantages and disadvantages. The Eulerian approach  is more general in
that it includes processes that mix air parcels and allows integrations to be carried out for long
periods during which individual air parcels lose their identity. There are, however, techniques for
including the effects of mixing in Lagrangian models such as FLEXPART (Zanis et al., 2003,
053423). ATTILA (Reithmeier and Sausen, 2002, 053447).  and CLaMS (McKenna et al., 2002,
053445). Because both the accuracy and the computational intensity of Eulerian models depend
strongly on the size of the horizontal and vertical grid spacing, speed and fidelity to actual
atmospheric conditions must sometimes be traded-off; that is to say, while finer  grid spacing will
often capture effects missed at larger grid intervals, models set up in this way require longer to solve.
In a similar manner, the accuracy of Lagrangian models depends on the number of air parcels
deployed;  thus they, too, become computationally intensive when higher-order accuracy is desired.
More detailed discussion of CTM applications appears in the 2008 ISA for NOX and SOX -
Ecological Criteria (U.S. EPA, 2008, 157074).


3.6.2.1.   Global Scale

      Global-scale CTMs are  used to address issues associated with climate change and
stratospheric O3 depletion to characterize long-range air pollution transport, and to provide boundary
conditions for the regional-scale models.  The CTMs include parameterizations of atmospheric
transport; the transfer of solar  radiation through the atmosphere; chemical reactions; and removal to
the surface by turbulent motions and precipitation for emitted pollutants. The upper boundaries of
the CTMs extend anywhere from the tropopause (~8 km at the poles to -16 km in the tropics) to the
mesopause at -80 km in order to obtain more realistic boundary conditions for problems involving
stratospheric dynamics and chemistry.
      Global simulations are typically conducted with a horizontal grid spacing of 200 km or more,
although some models such as GEOS-Chem have been run at grid spacings of about 100 km (e.g.,
Wu et al., 2008, 190039) and efforts are being made to achieve even higher spatial resolution.
Simulations of the effects of long-range transport at particular locations link multiple horizontal
resolutions from the global to  the local scale. Finer resolution can only improve scientific
understanding to the extent that the governing processes are  more accurately described at that scale.
Consequently, there is a crucial need for observations at the appropriate scales to evaluate the
scientific understanding represented by the models.


3.6.2.2.   Regional Scale

      Most major regional-scale air-related modeling efforts at EPA use the Community Multi-scale
Air Quality modeling system (CMAQ) (Byun and Ching, 1999, 156314; Byun  and Schere, 2006,
090560). A number of other modeling platforms using Lagrangian and Eulerian  frameworks were
reviewed in the 2006 O3 AQCD (U.S. EPA, 2006, 088089) and in Russell and Dennis (2000,
035563). The capabilities  of a number of CTMs designed to  study local- and regional-scale air
pollution problems were summarized by Russell and Dennis (2000, 035563). Evaluations of the
performance of CMAQ are given in Arnold et al. (2003, 087579). Eder and Yu (2005, 089229).
Appel et al. (2005, 089227). and Fuentes and Raftery (2005, 087580). CMAQ's horizontal domain
can extend from  a few hundred kilometers on a side to the entire hemisphere. CMAQ  is most often
driven by the MM5 mesoscale meteorological model (Seaman, 2000, 035562). though it may be
driven by other meteorological models including WRF and the Regional Atmospheric Modeling
System (RAMS); see http://atmet.com. Simulations of pollution episodes over regional domains
have been performed with a horizontal resolution as low as 1 km; see the application and general
survey results reported in  Ching et al. (2006, 090300). However, simulations at such high resolutions
require better parameterizations  of meteorological processes such as boundary layer fluxes, deep
convection and clouds (Seaman, 2000, 035562). Finer spatial resolution is necessary to resolve
features such as urban heat island circulation; sea, bay, and land breezes; mountain and valley
breezes; and the nocturnal low-level jet, all of which can affect pollutant concentrations.
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      The most common approach to setting up the horizontal domain is to nest a finer grid within a
larger domain of coarser resolution. However, there are other strategies such as the stretched grid
and the adaptive grid. In a stretched grid, the grid's resolution continuously varies throughout the
domain, thereby eliminating any potential problems with the sudden change from one resolution to
another at the boundary. Caution should be exercised in using such a formulation because certain
parameterizations like those for convection might be valid on a relatively coarse grid scale but may
not be valid on finer scales. Adaptive grids are not fixed at the start of the simulation, but instead
adapt to the needs of the simulation as it evolves. They have the advantage that they can resolve
processes at relevant spatial scales. However, they can be very slow if the situation to be modeled is
complex. Additionally, if adaptive grids are used for separate meteorological, emissions, and
photochemical models,  there is no reason a priori why the resolution of each grid should match, and
the gains realized from increased resolution in one model will be wasted in the transition to another
model. The use of finer horizontal resolution in CTMs will necessitate finer-scale inventories of land
use and better knowledge of the exact paths of roads, locations of factories, and, in general, better
methods for locating sources and estimating their emissions.
      The vertical resolution of these CTMs  is variable and usually configured to have more layers
in the PEL and fewer higher up. Because the height of the boundary layer is of critical importance in
simulations of air quality, improved resolution of the boundary layer height would likely improve air
quality simulations. Additionally, current CTMs do not adequately resolve fine-scale features such as
the nocturnal low-level jet in part because little is known about the nighttime boundary layer.
      CTMs require time-dependent, three-dimensional wind fields for the period of simulation. The
winds may be generated either by a model using initial fields alone or with four-dimensional data
assimilation to improve the model's performance; i.e., model equations can be updated periodically
to bring results into agreement with observations. Modeling series durations can range from
simulations of several days duration, the typical time scale for individual O3 episodes, to several
months or multiple seasons of the year. The current trend in modeling applications is towards annual
simulations. This trend is driven in part by the need to improve understanding of observations of
periods of high wintertime PM (Blanchard et al., 2002, 047598) and the need to simulate O3 episodes
occurring in spring, fall, and winter.
      Chemical kinetics mechanisms representing the important reactions occurring in the
atmosphere are used in  CTMs to estimate the rates of chemical formation and destruction of each
pollutant simulated as a function of time. Mechanisms that treat the reactions of all individual
reactive species explicitly are computationally too demanding to be incorporated into CTMs for
regulatory use. Similarly, very extensive "master mechanisms" (Derwent et al., 2001, 047912) that
include approximately 10,500 reactions involving 3,603 chemical species (Derwent et al., 2001,
047912) can be combined into mechanisms that group together compounds with similar chemistry.
Because of different approaches to the lumping of organic compounds into surrogate groups for
computational efficiency, chemical mechanisms can produce  different results under similar
conditions. The Carbon Bond chemical mechanisms starting with CB-IV (Gery et al., 1989, 043039),
the RADM II mechanism (Stockwell et al., 1990, 043095). the SAPRC (e.g., Carter, 1990, 042893:
Wang et al., 2000, 048357: Wang et al., 2000, 048365). and the RACM mechanisms can be used in
CMAQ. Jimenez et al. (2003, 156611) provided brief descriptions of the features of the main
mechanisms in use and  compared concentrations of several key species predicted by seven chemical
mechanisms in a box-model simulation over 24 h.
      CMAQ and other state-of-the-science CTMs incorporate processes and interactions of aerosol-
phase chemistry (Binkowski  and Roselle, 2003, 191769: Gaydos et al., 2007, 139738: Zhang and
Wexler, 2008, 191770). There have also been several attempts to study the feedbacks of chemistry on
atmospheric dynamics using meteorological models like MM5 and WRF (Grell et al., 2000, 048047:
Liu et al., 2001, 048201: Lu et al., 1997, 048202: Park et al., 2001, 044169). This coupling is
necessary to accurately  simulate feedbacks which may be caused by the heavy aerosol loading found
in forest fire plumes (Lu et al., 1997, 048202: Park et al., 2001, 044169) or in heavily polluted areas.
Photolysis rates in CMAQ can now be  calculated interactively with model produced O3, NO2, and
aerosol fields (Binkowski et al., 2007, 090563).
      Spatial and temporal characterizations of anthropogenic and biogenic precursor emissions
must be specified as inputs to a CTM. Emissions inventories have been compiled on grids of varying
resolution for many hydrocarbons, aldehydes, ketones, CO, NH3, and NOX. Emissions inventories
for many species require the application of algorithms for calculating the dependence of emissions
on physical variables, such as temperature, and to convert the inventories into formatted emission
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files which can be used by a CTM. For example, preprocessing of emissions data for CMAQ often is
done by the Spare-Matrix Operator Kernel Emissions (SMOKE) system (http://smoke-model.org).
For many species, information concerning the temporal variability of emissions is lacking, so long-
term annual averages are used in short-term, episodic simulations. Annual emissions estimates are
often modified by the emissions model to produce emissions more characteristic of the time of day
and season. Significant errors in emissions can occur if inappropriate time dependence is used.
Additional  complexity arises in model calculations because different chemical mechanisms can
include different species, and inventories constructed for use with one mechanism must be adjusted
to reflect these differences in another.


3.6.2.3.   Local or Neighborhood Scale

      The grid spacing in regional CTMs, usually between 1 and 12 km2, is usually too coarse to
resolve spatial variations on the neighborhood scale. The interface between regional scale models
and models of smaller exposure scales is provided by smaller scale dispersion models. Several
models could be used to simulate  concentration fields near roads, each with its own set of strengths
and weaknesses. The California Department of Transportation's most recent line dispersion model is
CALINE4; see http://www.dot.ca.gov/hq/env/air/pages/calinesw.htm. The CALINE family of
models is not supported by the California Department of Transportation for modeling of highway-
source PM, however, but only for roadway CO, although PM work with CALINE has been
performed for more than ten years; see Wu et al. (2009, 191773) and references therein.
      In addition, AERMOD (http://www.epa.gov/scram001/dispersionjrefrec.htm) is a steady-
state plume model formulated as a replacement to the ISC3 dispersion model. In the stable boundary
layer (SBL), it assumes the concentration distribution to be Gaussian in both the vertical and
horizontal dimensions. In  the convective boundary layer, the horizontal distribution is also assumed
to be Gaussian, but the vertical distribution is described with a bi-Gaussian probability density
function (pdf). AERMOD has provisions that can be applied to flat and complex terrain and multiple
source types (including, point, area and volume sources) in both urban and rural areas. It
incorporates air dispersion based on the structure of turbulence in the PEL and scaling concepts and
is meant to treat surface and elevated sources, in both simple and complex terrain in rural and urban
areas. The dispersion of emissions from line sources like highways in AEROMOD is handled as a
source with dimensions set using an area or volume source algorithm in the model; however, actual
emissions are usually not in  steady state and there are different functional relationships between
buoyant plume rise in point and line sources. Moreover, most simple dispersion models including
AERMOD  are designed without chemical mechanisms and so cannot produce secondary pollutants
from their primary emissions .
      There are also non-steady state models that incorporate plume rise explicitly from different
types of sources. For example, CALPUFF  (http://www.src.corn/calpuff/calpuff 1 .htm), which is
EPA's recommended dispersion model for transport in ranges >50 km, is a non-steady-state puff
dispersion model that simulates the effects of time- and space-varying meteorological conditions on
pollution transport, transformation, and removal and has provisions for calculating dispersion from
surface sources. However, CALPUFF was not designed to treat the dispersion of emissions from
roads, and like AERMOD does not include production of secondary pollutants.  The distinction
between a steady-state and time varying model could be unimportant for long time scales; however,
at short time scales, the temporal variability in traffic emissions could result in underestimation of
peak concentration and exposures.


3.6.3.   Air Quality Model  Evaluation for Air Concentrations

      Urban and regional  air quality is determined by a complex system of coupled chemical and
physical processes including emissions of pollutants and pollutant precursors, complex chemical
reactions, physical transport and diffusion, and wet and dry deposition. NOX in these systems has
long been known to (1) act nonlinearly in the production of O3 and other secondary pollutants
(Dodge, 1977, 038646): and (2) involve complicated cross-media environmental issues, such as
acidic or nutrient deposition to sensitive biota and degradation of visibility.
      NOY species emitted and transformed from emissions control the production and fate of both
O3 and aerosols by sustaining or suppressing OH cycling. Correctly characterizing the interrelated
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NOY and OH dynamics for O3 formation and fate in the polluted troposphere depends on new
techniques using combinations of several NOY species for diagnostically probing the complex
atmospheric dynamics in typical urban and regional airsheds.
      Evaluation results from a recent EPA exercise of CMAQ in the Tampa Bay, FL, airshed are
presented here as an example of the present level of skill of state-of-the-science AQMs for predicting
atmospheric concentrations of some of the relevant species for this PM NAAQS assessment.  This
modeling series exercised CMAQ version 4.4 and with the University of California at Davis (UCD)
sectional aerosol module in place of the standard CMAQ modal aerosol module and was driven by
meteorology from MM5 v3.6 and with NEI emissions as augmented by continuous emissions
monitoring data where available. The UCD size-segregated module was preferred for this application
because of the  importance of sea salt particles in the bay airshed. Testing of this new engineering
extension to CMAQ (termed CMAQ-UCD below) revealed that its performance was very similar to
that of CMAQ's standard modal module; hence, model behavior and performance reported here can
stand as a general indication of CMAQ's skill.
      The CTM was run with 21 vertical layers for the month of May 2002. For this evaluation,
CMAQ-UCD was run in a one-way nested series of three domains with 32 km, 8 km, and 2 km
horizontal grid spacings from the CONUS (32 km) to central Florida and the eastern Gulf of Mexico
(2 km). Depictions of the 8 km and 2 km domains used here zoomed over the central Tampa area are
shown in Figure 3-58 and Figure 3-59.
December 2009                                3-114

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                8KM RESOLUTION; ZOOME
Figure 3-58.  Eight km southeast U.S. CMAQ-UCD domain zoomed over Tampa Bay, FL.
                 KM RESOLUTION; ZOOMED2





                                 I
Figure 3-59.  Two km southeast U.S. CMAQ-UCD domain zoomed over Tampa Bay, FL.
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                       ST
                        012345678 91011121314151617181920212223
                                           Hours (EST)
                         012345
                                            10 11 12 13 14 15 16 17 18 19 20 21 22 23
                                            Hours (EST)
                         012345
                                            10 11 12 13 14 15 16 17 18 19 20 21 22 23
                                            Hours (EST)
Figure 3-60.   Hourly average CMAQ-UCD predictions and measured observations of NO (top),
              N02 (middle), and total NOX (bottom) concentrations for May 1-31, 2002.  Green
              squares = 8 km solution, red diamonds = 2 km solution, blue circles =
              observations.
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                          1 -May 2-May 3-May 4-May 5-May 6-May 7-May 8-May 9-May 10-
                                                                  May
                                        Hours (date mark = 0000 EST)
                          4-r
                          3--
                           11-  12-   13-  14-   15-  16-  17-   18-  19-  20-
                           May  May  May  May  May  May  May  May  May  May

                                        Hours (date mark = 0000 EST)
                          21-   22-  23-  24-  25-  26-  27-  28-  29-   30-  31-
                          May May  May  May  May  May  May  May May May May
                                        Hours (date mark = 0000 EST)
Figure 3-61.   CMAQ-UCD predictions and measured observations of ethene concentrations at
               Sydney, FLfor May 1-31, 2002.  Green squares = 8 km solution, blue circles =
               observations.
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                           6--
                         Ul M
                         E 4 - •
                           2--
                           1 -May 2-May 3-May 4-May 5-May 6-May 7-May 8-May 9-May 10-
                                                                    May
                                         Hours (date mark = 0000 EST)
                          11 -May 12-May 13-May 14-May 15-May 16-May 17-May 18-May 19-May 20-May
                                           Hours (date mark = 0000 EST)
                            4T
                             21-   22-   23-  24-  25-  26-  27-  28-  29-  30-  31-
                             May  May  May  May  May  May  May  May  May  May  May
                                            Hours (date mark = 0000 EST)
Figure 3-62.    CMAQ-UCD predictions and measured observations of isoprene concentrations
                at Sydney, FL for May 1 -31, 2002.  Green squares = 8 km solution, blue circles =
                observations.
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                           60 T
                           10
                           1 -May 2-May 3-May 4-May 5-May 6-May 7-May 8-May 9-May 10-
                                                                     May
                                         Hours (date mark = 0000 EST)
                           11 -May 12-May 13-May 14-May 15-May 16-May 17-May 18-May 19-May 20-May
                                            Hours (date mark = 0000 EST)
                           60 T
                         — 40 -


                         I
                         3.30 +
                           o I . i i i . i . i . i i i  . i . i . i . i i i . i . i . i i i . i . i . Y i I i I . I

                            21-  22-  23-  24-  25-  26-  27-  28-  29-  30-  31-
                            May  May  May  May  May  May  May  May  May  May  May
                                            Hours (date mark = 0000 EST)
Figure 3-63.    CMAQ-UCD predictions and measured observations of PIVk.e concentrations at
                Sidney, FLfor May 1-31, 2002. Green squares = 8 km solution, blue circles =
                observations.
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3.6.3.1.   Ground-based Comparisons of Photochemical Dynamics

      Errors in the NOX concentrations in the model, most likely from on-road emissions, affected
NOX predictions shown in Figure 3-60, but CMAQ-UCD's general responses were reasonable. The
model also replicated anthropogenic and biogenic VOC emissions well; see Figure 3-61 and Figure
3-62,  respectively. After initial errors leading to underprediction in the first 21 days, CMAQ-UCD's
predictions of hourly PM2.5 concentrations and trends over the whole month also replicated the
observed concentrations well (Figure 3-63).


3.6.3.2.   Predicted Chemistry for Nitrates and Related Compounds

      Particulate NO3~ (pNO3~) plays a crucial and complex role in the health of aquatic and
estuarine ecosystems and  human drinking water systems. Gas-phase NO3~ replacement of CPon sea
salt particles is often favored thermodynamically and the Vd of the coarse pNO3~ formed through this
replacement is more than  an order of magnitude greater than for fine pNO3~. Over open bodies of salt
water such as the Gulf of Mexico and Tampa Bay, FL, pNO3~ from this reaction dominates dry
deposition and is estimated to be of the same order as pNO3~ wet deposition.
      However, total NO3~ concentrations are driven, buffered, and altered by a wide range of
photochemical gas-phase  reactions, heterogeneous reactions, and aerosol dynamics, making them
especially difficult to model.  Because pNO3~ is derived  mostly from gas-phase HNO3 and will
interact with Na+, NH4+, Cl~,  and SO42~, all these species and the physical parameters governing their
creation, transport, transformation, and fate must be  accurately replicated to predict pNO3~ with high
fidelity. This has historically  been a difficult problem for numerical process models, owing in large
part to the pervasive dearth of reliable ambient measurements of NOjT in its various forms.
Normalized mean error (NME) for the large-scale Eulerian CTM-predicted pNO3~ has typically been
on the order of a factor of 3 greater than the NME for particulate SO42~ (pSO42~) (Odman et al, 2002,
092474: Pun et al 200+3,  047775).
      SO42~, NH4+, Na+, and Crwere all predicted to within a factor of 2 and with no significant bias
during the photochemical day in the 8 km CMAQ-UCD solution, although a significant bias in Na+
and CPwas evident in the 2 km solution for two near-water sites. This grid-size dependent bias is
still being explored.  Size segregation maxima were correct to within two size bins every day for
which there were observations for both SO42~and NH4+  (0.2  to 1.0  urn), and Na+ and Cl
(2.0-10.0 urn). Cl~ concentrations were greatly overpredicted during dark hours, but were nearer to
observed values during the photochemical day. CMAQ-UCD performance for HNO3 and NH3 are
shown in Figure 3-64 and Figure 3-65, respectively.
      Figure 3-66 shows that CMAQ-UCD systematically underpredicted the hourly time series of
measured pNO3~ concentrations at the Sydney supersite, the  only location with discrete pNO3~ data.
These time series data establish that CMAQ-UCD's  largest errors were on 4 days in the first 2 wk of
the month, but that the total peak pNO3~ concentrations  were nearly all underpredicted.
      Since pNO3~ is derived in large part from gas-phase HNO3, its underprediction may be due to
an underprediction of HNO3 concentrations or an underrepresentation of the gas- to aerosol-phase
change. At Sydney, FL, in fact, both these conditions held. Figure 3-64 depicts  the model's bias for
HNO3 underprediction in  both the 8 km and 2 km solutions,  except for four days of very large peak
overpredictions. This pattern of underpredictions was especially evident overnight. On 8 other days
the model overpredicted the one hour peak concentration as  well, though not so substantially, but the
chief effect was still one of an artificial and inappropriate N  limitation in the model.
      A time series molar equivalent ratio of HNO3 to total NO3 depicts which phase stores the NO3~
and how that storage ratio changes over time. Figure 3-67 shows that at Sydney, FL, CMAQ-UCD
stored too much NO3~ in the gas phase as HNO3 (and recall that the daytime HNO3 concentrations
were sometimes overpredicted by the model) and too little in the gas phase overnight, when the
model was regularly low against the measurements;  compare Figure 3-64 and Figure 3-65. Note
again here the similarity of the 8 km and 2 km solutions in this comparison.
      Interestingly, the 23-h integrated data did not reveal this important difference in NO3~ form
between the model and measurements as Figure 3-68 shows  in the  stacked bar percentage plots of
fine and coarse pNO3~ together with gas-phase HNO3. Both the 8 km (Figure 3-68, middle panel)
and the 2 km (Figure 3-68, bottom panel) solutions predicted distributions between the two general
ranges of aerosol size,  and between gas and aerosol phases, with good fidelity to the daily
observations (Figure 3-68, top panel) at Sydney, FL. This result illustrates  that while discrete time
December 2009                                 3-120

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series data are crucial for diagnosing model behavior, on the integrated total daily and longer basis
used for computing total annual N loads, CMAQ-UCD predicted approximately the correct
distributions for pNO3~, even though the total NO3~ concentration prediction was biased low.
                           1-May 2-May 3-May 4-May 5-May 6-May 7-May 8-May 9-May 10-
                                                                  May
                                         Hours (Date Mark = 0000 EST)
                           11-May 12-May 13-May 14-May 15-May 16-May 17-May 18-May 19-May 20-May
                                          Hours (Date Mark = 0000 EST)
                           21-May22-May23-May24-May25-May26-May27-May28-May29-May30-May31-May
                                          Hours (Date Mark = 0000 EST)
Figure 3-64.   CMAQ-UCD predictions of HMOs' concentrations and corresponding measured
               observations at Sydney, FL, for May 1-31, 2002.  Green x = 8 km solution, red
               diamonds = 2 km solution, blue circles = observations.
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                          1 -May 2-May 3-May 4-May 5-May 6-May 7-May 8-May 9-May  10-
                                                                    May
                                         Hours (date mark = 0000 EST)
                         22 T
                           11-   12-   13-   14-  15-   16-   17-  18-   19-  20-
                           May  May  May   May  May  May   May  May  May  May
                                         Hours (date mark = 0000 EST)
                          21 -May22-May23-May24-May25-May26-May27-May28-May29-May30-May31 -May
                                         Hours (date mark = 0000 EST)
Figure 3-65.   CMAQ-UCD predictions of NH3 concentrations and corresponding measured
               observations at Sydney, FL, for May 1-31, 2002. Green x = 8 km solution, red
               diamonds = 2 km solution, blue circles = observations.
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                          1-May 2-May 3-May 4-May 5-May 6-May 7-May 8-May 9-May


                                         Hours (date mark = 0000 EST)
                     10-
                     May
                         11-May 12-May 13-May 14-May 15-May 16-May 17-May 18-May 19-May 20-May
                                         Hours (date mark = 0000 EST)
                         21-May22-May23-May24-May25-May26-May27-May28-May29-May30-May31-May
                                         Hours (date mark = 0000 EST)
Figure 3-66.   CMAQ-UCD predictions of pN03" concentrations and corresponding measured
               observations at Sydney, FL, for 1-31 May, 2002.  Green x = 8 km solution, red
               diamonds = 2 km solution, blue circles = observations.
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                          1.Oi-
                           l-May  2-May 3-May 4-May 5-May 6-May  7-May 8-May 9-May 10-May
                                          Hours (date mark = 0000 EST)
                          0.0
                           11-May 12-May 13-May 14-May 15-May 16-May 17-May 18-May 19-May 20-May

                                           Hours (date mark = 0000 EST)
                          1.0 T
                          21-May22-May23-May24-May25-May26-May27-May28-May29-May30-May31-May

                                            Hours (date mark = 0000 EST)
Figure 3-67.    CMAQ-UCD predictions of the ratio of HN03 to total N03 and corresponding
                measured observations at Sydney, FL, for May 1-31, 2002. Green x = 8 km
                solution, red diamonds = 2 km solution, blue circles = observations.
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                                       MOUCH aerosol NO3 and ARA HNO3 (23 h daily mean)
                                 5/1  5/3  5/5 5/7 5/9 5/11 5/13 5/15 5/17  5/19 5/21 5/23 5/25 5/27 5/29 5/31

                                                     Date, 2002
                                            • <25un  125-IOuii  DHNO3
                                         CMAQ-UCD 8 km solution (23 h daily mean)
                                 5/1  5/3  5/5 5/7 5/9 5/11 5/13 5/15 5/I7  5/19 5/21 5/23 5/25 5/27 5/29 5/31

                                                     Date, 2002
                                            • < 2.5 mi  125-10 urn  DHNO3
                                          CMAQ-UCD 2 km solution (23 HOT Means)
                                 5/1  5/3  5/5 5/7 5/9 5/11 5/13 5/15 5/17  5/19 5/21 5/23 5/25 5/27 5/29 5/31

                                                     Date. 2002
                                            • <2.5 urn  •2.5-10UI11  BHNO3
Figure 3-68.   CMAQ-UCD predicted size and chemical-form fractions of total N03" for days in
                May 2002 with measured observations. Measured concentrations (top panel);
                8 km solution (middle panel); 2 km solution (bottom panel). Red bars = pN03" <2.5
                urn; blue bars = pN03" 2.5-10 urn; green bars = HN03.
December 2009
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      While inorganic aerosol anion totals were dominated by NO3 in the coarse fraction and by
SO42~ in the fine fraction, there was sufficient NHX (NHX = NH3 + NH4+) at Sydney, FL, to form fine
aerosol NH4NO3 in some circumstances. Figure 3-65 depicts the hourly mass concentration of NH3
at Sydney, FL, showing again the strong similarity of the 8 km and 2 km solutions. Each solution,
however, underpredicted the measured NH3 concentrations consistently, and especially for the nine
very large excursions of 10-20  ug/m3 during the month.
      Overall, CMAQ-UCD was found to be operationally sound in this evaluation of its 8 km and
2 km solutions for the Tampa Bay airshed using the ground-based and aloft data (not shown here)
from the May 2002 field intensive. Moreover, results from diagnostic tests of the model's
photochemical dynamics were generally in excellent agreement with results from the ambient
atmosphere. However, CMAQ-UCD was biased low in this application for total NO3 and for NO3
present as gas-phase HNO3. In  addition, the model was biased low for the HOX radical reservoir
species CH2O and H2O2 (not shown here), though this bias appeared to have been limited to these
species. Performance of the new UCD  aerosol module was judged to be entirely adequate, allocating
aerosols by chemical makeup to the appropriate size fractions. Model performance for fine-mode
aerosols was also judged to be fully adequate.


3.6.4.   Evaluating Concentrations and  Deposition  of PM  Components
         with CTMs
3.6.4.1.  Global CTM Performance

      The wet and dry deposition processes described in Section 3.3 are of necessity highly
parameterized in all CTMs. While all current models implement resistance schemes for dry
deposition, the Vd generated from different models can vary highly across terrain types (Stevenson et
al., 2006, 089222).The accuracy of wet deposition in global CTMs is tied to spatial and temporal
distribution of model precipitation and the treatment of chemical scavenging. Dentener et al. (2006,
088434) compared wet deposition across 23 models with available measurements around the globe.
Figure 3-69 and Figure 3-70 extract results of a comparison of the 23-model mean versus
observations over the eastern U.S.  for pNO3~ and pSO42~ deposition, respectively. The mean model
results were strongly correlated with the observations (r >0.8), and usually captured the magnitude of
wet deposition to within a factor of two over the eastern U.S. Dentener et al. (2006, 088434)
concluded that 60-70% of the participating models captured the measurements to within 50% in
regions with quality controlled observations.
December 2009                                 3-126

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                             600
                             400
                             200
                                          200         400         600

                                             Measurement

                                       Source: Adapted with Permission of American Geophysical Union from Dentener et al. (2006, 088434).
Figure 3-69.   Scatter plot of total nitrate (HN03 plus pN03") wet deposition (mg N/m2/yr) of the
              model mean versus measurements for the North American Deposition Program
              (NADP) network. Dashed lines indicate a factor of two. The gray line is a linear
              regression through zero.
                           1000
                           800
                           600
                           400
                           200
                                                        I *
                                        '   I      t'Jm    *
                                  •    / .    •   **"
                             0 C±
'''"•••|"j*i    ."
V V f*  •
\v  •     ',.
I  ** •  .    ^	
                                 >  ""'"
                                <*-'
                                    200
                                           400     600

                                            Measurement
                                                          800
                                                                1000
                                       Source: Adapted with Permission of American Geophysical Union from Dentener et al. (2006, 088434).
Figure 3-70.   Scatter plot of total S042" wet deposition (mg S/m2/yr) of the model mean versus
              measurements for the National Atmospheric Deposition Program (NADP)
              network.  Dashed lines indicate a factor of two. The gray line is a linear
              regression through zero.
3.6.4.2.   Regional CTM Performance

      Regional CTM performance for concentration and deposition of some of the most relevant PM
species is illustrated here with examples from CMAQ version 4.6.1 as configured and run for
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exposure and risk assessments reported in the Risk and Exposure Assessment for the Review of the
Secondary National Ambient Air Quality Standards for Oxides of Nitrogen and Oxides of Sulfur
(U.S. EPA, 2009, 191774); additional details on the model configuration and application are found
there. A map of the 36 km parent domain and two 12 km (east and west) progeny domains appears in
Figure 3-71.
Figure 3-71.   CMAQ modeling domains for the OAQPS risk and exposure assessments: 36 km
              outer parent domain in black; 12 km western U.S. (WUS) domain in red; 12 km
              eastern U.S. (EUS) domain in blue.

      Comparisons from the 2002 annual run of CMAQ for the exposure assessment are shown here
against measured concentrations and deposition totals from nodes in three networks: IMPROVE,
CSN (labeled STN in the plots) and CASTNet. Comparisons were made as model-observation pairs
at all sites having sufficient data for the seasonal or the 2002 annual time period in the two 12 km
east and west domains and were evaluated with the following descriptive statistics: correlation, root
mean square error, normalized mean bias, and normalized mean error.
      Summertime pSO42~ concentrations are well predicted by CMAQ, to within a factor of 2 at
nearly every point, and with R2 >0.8 across all three networks (Figure 3-72). This result tracks the
generally well-predicted SO42~ concentrations found in earlier CMAQ evaluations: see Eder and Yu
(2005, 089229). Mebust et al. (2003, 156749) and Tesche et al. (2006, 157050). Since pSO42~
concentrations are strongly  a function of precipitation, care must be taken to ensure that the
meteorological solution driving individual CMAQ chemical applications produces precipitation
fields with low bias as discussed by Appel et al. (2008, 155660).
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                         2002ac_met2v33_12kmE SO4 for June to August 2002
            CM _
        O
                 a  IMPROVE (2002ac_met2v33_12kmE)
                 A  STN(2002ac_met2v33_12kmE)
                    CASTNet (2002ac_met2v33_12kmE)
                                                              Monthly Average
                                                                SO4  ( ug/m3
                                                    2002ac met2v33 12kmE
                                                     CORR RMSE  NMB  NME
                                            IMPROVE  0.96  0.84  -11.7  17.2
                                              STN    0.83  1.57  0.4   20.1
                                            CASTNet  0.97  0.83  -8.6  12.5
Figure 3-72.
                            Observation

12-km EUS Summer sulfate PM. Each data point represents a paired monthly
averaged (June/July/August) observation and CMAQ prediction at a particular
IMPROVE, STN, and CASTNet site. Solid lines indicate a factor of two around the
1:1 line shown between them.
     Wintertime pNO3 (Figure 3-73) and total NO3 (HNO3+pNO3 ) (Figure 3-74) concentrations
are predicted less well by CMAQ, but NO3 is a pervasively difficult species to measure and model.
Still, at the CASTNet nodes where the total NO3 concentrations are higher than they are at all but a
few of the remote IMPROVE sites, CMAQ predicts concentrations for nearly every node to within a
factor of 2 and with an R2 >0.8.  These CMAQ-predicted concentrations, coupled with modeled cloud
and precipitation fields produce wet deposition fields for SO42~ and NO3~ in the east domain as
shown in Figure 3-75 and Figure 3-76, respectively.
December 2009
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-------
                     2002ac_met2v33_12kmE NO3 for December to February 2002
           oo -
           CD -
        O
           OJ -
                    IMPROVE (2002ac met2v33 12kmE)
                A   STN(2002ac_met2v33_12kmE)
                                                            Monthly Average
                                                             A NO3 ( ug/m3 )
                                                  2002ac met2v33 12kmE
                                                   CORR RMSE  NMB  NME
                                           IMPROVE  0.73  0.69   0.5  47
                                             STN    0.67  1.32  -6.9  35.7
                                        Observation


Figure 3-73.   12-km EUS Winter nitrate PM. Each data point represents a paired monthly
             averaged (December/January/February) observation and CMAQ prediction at a
             particular IMPROVE and STN site. Solid lines indicate a factor of two around the
             1:1 line shown between them.
December 2009
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                      2002ac_met2v33_12kmE TNO3 for December to February 2002
             CD -
          1  *
          O
             CO
             (M -
             o -I
                  n  CASTNet (2002ac met2v33 12kmE)
                                                             Monthly Average
                                                              TNO3 ( ug/m3 )
                                                    2002ac_met2v33_12kmE

                                                    CORR RMSE  NMB  NME
                                             CASTNet  0.85 0.88  -1.6  21.4
                                 \

                                2
3
       i
      4

Observation
5
6
7
Figure 3-74.   12-km EUS Winter total nitrate (HMOs + total pNCV). Each data point represents a
              paired monthly averaged (December/January/February) observation and CMAQ
              prediction at a particular CASTNet site. Solid lines indicate a factor of two around
              the 1:1 line shown between them.
December 2009
  3-131

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                        2002ac met2v33 12km E SO4 for 20020101 to 20021231
           co
           o
           CO
           LD
           C\]
           o
           C\]
       o
           o .
           LO -
Q   NADP_dep(2002ac_met2v33_12kmE)
IA
RMSE =
RMSEs =
RMSEu =
MB
ME
MdnB  =
MdnE  =
                                                           Period Accumulated
                                                                SO4 ( kg/ha
                                         Observation
Figure 3-75.   12-km EUS annual sulfate wet deposition. Each data point represents an annual
             average paired observation and CMAQ prediction at a particular NADP site. Solid
             lines indicate the factor of 2 around the 1:1 line shown between them.
December 2009
                          3-132

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                          2002ac met2v33 12kltlE NO3 for 20020101 to 20021231
           O
           O
                   n   NADP_dep(2002ac_met2v33_12kmE)
                                                           Period Accumulated
                                                                NO3 ( kg/ha
                                               15

                                           Observation
Figure 3-76.   12-km EUS annual nitrate wet deposition. Each data point represents an annual
              average paired observation and CMAQ prediction at a particular NADP site. Solid
              lines indicate a factor of two around the 1:1  line shown between them.

      Importantly, CMAQ captured the chief spatial patterns  and magnitudes of air concentrations
and wet deposition relevant to computing concentration and deposition budgets, as shown in Figure
3-77 for concentrations and Figure 3-78 for deposition. More specifically, CMAQ's predictions of
NH3 and SO42~ for both high and low concentration sites are well within the range of observed
measurements (Figure 3-79).
December 2009
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                           iv17 SO4 for June to August 2002
                                                        J4c_emisv17 NH4 for June to August 2001
                   MPROV= (J4c_emisv17
                   STN |J4c_.srnlsv17)
                   CASTNe: [J4c_emisv17)
                                        monthly average

                                       SO4 (ug/m3}

                                  HPQ - None
                                  Slate = All   Site = All
6    8   10

Observation
                                                            234

                                                              Observation
Figure 3-77.   CMAQ vs. measured air concentrations from east-coast sites in the IMPROVE,
              CSN (labeled STN), and CASTNet sites in the summer of 2002 for sulfate (left) and
              ammonium (right). Solid lines indicate a factor of 2 around the 1:1 line shown
              between them.
                      CMAQ Ammonium Ion Wet Deposition
                                                                 WET NH4 DEPOSITION (KG/HA)

                                                                      CMAQ (Ml

                                                                VS. NADP (2001-2003 AVERAGED)

                                                              LIMITED TO SITES IN THE EASTERN U.S.

                                                                      ANNUAL
                         __                    _                  01234567

                      NADP Ammonium Ion Wet Deposition                 NADP
                                                            LEGEND

                                                         REGRESSION THROUGH ORIGIN  ^—^—
                                                         RUNNING MEDIAN SMOOTH UNE
                                                         NADP SITES IN CHESAPEAKE BAY *
              200  2003200
Figure 3-78.   Comparison of CMAQ-predicted and NADP-measured NH4+ wet deposition : (top
              left) CMAQ prediction; (bottom left) NADP-measurements; (right) regression and
              smoothed median line through CMAQ predictions and NADP measurements with
              sites in the Chesapeake Bay watershed highlighted.
December 2009
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              Kenansville Ammonia July 2004
                   12-hour Averages: 6am-6pm
        184 186 188 190 192 194 196 198 200 202 204 206 208 210 212 214

                 Julian Day: TickMark at Midnight (July 2004)
                    -Kenansville NH3 -B-CMAQ-J4C NH3
             Kenansville Sulfate July 2004
                 12-hour Averages: 6am-6pm
       184 186 188 190 192 194 196 198 200 202 204 206 208 210 212 214

               Julian Day: TickMark at Midnight (July 2004)
                                                                 - Kenansville SO4 -•- CMAQ-J4C ASO4
           Millbrook (Raleigh) Ammonia July 2004
                   12-hour Averages: 6am-6pm
               190 192 194 196 198 200 202 204 206 208 210 212 214

                Julian Day: TickMark at Midnight (July 2004)
                              CMAQ-J4C NH3
          Millbrook (Raleigh) Sulfate July 2004
                 12-hour Averages: 6am-6pm
              190 192 194 196 198 200 202 204 206 208 210 212 214

               Julian Day: TickMark at Midnight (July 2004)
                                                                          CMAQ-J4C ASO4
Figure 3-79.   CMAQ-predicted (red symbols and lines) and 12-h measured (blue symbols and
               lines) NH3 and S042~ surface concentrations at high and low concentration grid
               cells in North Carolina in July 2004.  (top left) High concentration NH3 in
               Kenansville; (top right) high concentration S042~ in Kenansville; (bottom left) low
               concentration NH3 in Raleigh; (bottom right) low concentration S042~ in Raleigh.

      Deposition velocities are difficult to estimate for reasons described in Section 3.3.3. Recent
work in EPA's Atmospheric Modeling and Analysis Division with CMAQ showed that the original
Vd for NH3 was very likely too high and should be nearer to the values for SO2 deposition, or even
lower over some land use surface types. A sensitivity  study with the model was performed to test the
effects of changing Vd for NH3 on the fraction of NH3 available for transport away from grid cells
with high emissions concentrations. Comparisons were made for the surface grid cells and total
column NH3 concentrations.
      In the highest emissions grid cells during June 2002, the surface NHX budget was dominated
by turbulent transport or vertical mixing moving a majority of the surface NH3 emissions up and
away from the surface into the mixed layer. Figure 3-80 depicts the NHX budget  under the base case
(Base Vd) and the sensitivity case (SO2 Vd) for which the NH3 Vd was set equal to the SO2 Vd. Lower
NH3 Vd decreased NHX deposition to the surface from 15  to 8%, leaving more NHX for transport
horizontally, 22% up from 20% in the base case, and vertically, 69% up from 64% in the base case.
Typically, -67% of surface emissions were moved aloft where most was advected away from the
high emissions grid  cell, with a small fraction converted to pNH4+ and an even smaller fraction wet-
deposited to the surface. The total column analyses for NH3 and NHX are shown  in Figure 3-81.
December 2009
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                    	 0.04%
                    38m Gas to
                 Surface partiriP
                              69-64%.
                              Vertical
                              Diffusior
                                                     TTTlun*
                                        Free Troposphere
                                          Mixed Layer (-2km)
 22-20%
Horizontal
Advection
                                       8-15%
                                   Dry Deposition
                             NH3
                           Emissions

                         NH3 Layer 1 Analysis
                    Right Number: BaseVd
                    Left Number: SO2Vd
Figure 3-80.   Surface grid cell (layer 1) analysis of the sensitivity of NHX deposition and
              transport to the change in NH3 Vd in CMAQ.


2.1-2.2%
Gas to Particle
Conversion
(unusually
low)
N
Enii
NH3Cc


C

•fopoj Model - 16km
Free Troposphere
89-82%
Horizontal
'Advection Mixed Layer( -2km)
\ * 0.55-0.54%
1 Wet Deposition
TT T
n3 Dry Deposition
ssions 8-15%
lunin Analysis
Right Number: BaseVd
Left Number: SOjVd
N
Emi
NHX(.


\ \ v
H3 Dry
ssions
Column /

91-84%
Horizontal
"" Advection
~0.58-0.57%
i'et Deposition
Deposition
8-15%
Analysis
Figure 3-81.   Total column analysis for NH3 (left) and NHX (right) showing modeled NH3
              emissions, transformation, and transport throughout the mixed layer and up to
              the free troposphere.

      Local total deposition  (wet + dry) is a significant but not dominant loss pathway for surface
NH3 emissions. In these simulations, CMAQ deposited -25% of the NH3 emissions from the single
high concentration grid cell in Sampson County, NC, back into that grid cell. By far, the largest
contribution to the local deposition total was dry deposition. Dry-to-wet deposition ratios for the
Sampson County high emissions grid cell and surrounding surface grid cells ranged from 2 to 10.
      Deposition to grid cells farther away from the high concentration, immediately surrounding
grid cells, was significantly affected by the change in NH3 Vd tested in this case. Figure 3-82 depicts
December 2009
     3-136

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the range of influence of the high concentration grid cell, where that range is defined to be the
distance by which 50% of the emissions attributable to that grid cell have deposited. The range of
influence of the high concentration Sampson County grid cell was extended in the Vd sensitivity
tested here from -180 km in the base case to -400 km in the case using the lower, more  realistic V
for NH3. The areal extent of this difference in range of influence is mapped in Figure 3-83.
                June 2002 NHx Range of Influence: BaseVd vs. SO2Vd
                             Sampson County (single cell)
                                 Distance from Center (km)
                           - -•- -Wet+Dry Dep BaseVd — •
                           — o— Wet+Dry Dep SO2Vd — a
          Advection BaseVd
          Advection SO2Vd
Figure 3-82.   Range of influence (where 50% of emitted NH3 deposits) from the high
              concentration Sampson County grid cell in the June 2002 CMAQ simulation of Vd
              sensitivities. Base case and sensitivity case total deposition (blue symbols and
              lines); base case and sensitivity case advection totals (red symbols and lines).
December 2009
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Figure 3-83.   Areal extent of the change in NHX range of influence as predicted by CMAQ for
             the Sampson County high concentration grid cell (center of range circles) in June
             2002 using the base case and sensitivity case Vd.
December 2009
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3.7.  Background PM
      The background concentrations of PM that are useful for risk and policy assessments
informing decisions about the NAAQS are referred to as policy-relevant background (PRB)
concentrations. PRB concentrations have historically been defined by EPA as those concentrations
that would occur in the U.S. in the absence of anthropogenic emissions in continental North America
defined here as the U.S., Canada, and Mexico. For this document, PRB concentrations include
contributions from natural sources everywhere in the world and from anthropogenic sources outside
continental North America. Background concentrations so defined facilitated separation of pollution
that can be controlled by U.S. regulations or through international agreements with neighboring
countries from those that were judged to be generally uncontrollable by the U.S. Over time,
consideration of potential broader ranging international agreements may lead to alternative
determinations of which PM source contributions should be considered by EPA as part of PRB.


3.7.1.   Contributors  to  PRB Concentrations of PM

      Contributions to PRB concentrations  of PM include both primary and secondary natural and
anthropogenic components.  Natural sources include wind erosion of natural surfaces (Gillette and
Hanson, 1989, 030212); volcanic production of SO42~;  PBAP; wildfires producing EC, OC, and
inorganic and organic PM precursors; and SOA produced by oxidation of biogenic hydrocarbons
such as isoprene and terpenes. However, human intervention can be involved in the formation of
SOA, as production of natural SOA depends to a large  extent on the presence of anthropogenic NOX.
As described earlier in Section 3.3, prescribed fires are considered part of PRB. In addition to
emissions from forest fires in the U.S., emissions from forest fires in other countries can be
transported to the U.S. For example, Boreal forest fires in Canada (Mathur, 2008, 156742)  and
Siberia (Generoso et al., 2007, 155786) and tropical forest fires in the Yucatan Peninsula and Central
America (Wang et al., 2006, 157109) have affected PM concentrations in the U.S. PRB PM varies
across the contiguous Unites States  (CONUS) by region and season as a function of the complex
mechanisms of transport, dispersion, deposition, and reentrainment.
      Dust from the Sahara desert and the Sahel in North Africa (Chiapello et al., 2005, 156339)
affects mainly the eastern U.S.; dust from the Gobi and Taklimikan deserts in Asia (VanCuren and
Cahill, 2002, 157087; Yu et al.,  2008, 157168) have the largest effects in the western U.S. but also
affect air quality in the eastern U.S.  Husar et al. (2001, 024947) report that the average PMi0
concentration at 25 reporting stations throughout the northwestern U.S. reached 65 ug/m3 during an
episode in the last week in April 1998, compared to an average of 10-25 ug/m3 during the rest of
April and May. This was accompanied by visual reports of milky-white discoloration of the normally
blue sky in non-urban areas along the west coast.
      PRB contributions to PM2.5, PMi0_2.5,  and PMi0 can also be viewed as coming from two
conceptually separate components: a reasonably consistent "baseline" component and an episodic
component. The baseline component consists of contributions that are generally well characterized
by a reasonably consistent distribution of daily values each year, although there is variability by
region and season. The episodic component consists of infrequent, sporadic contributions from
natural high-concentration events occurring over shorter periods of time (e.g., hours to several days)
both within North America (e.g., volcanic eruptions, large  forest fires, dust storms) and outside
North America (e.g., transport related to dust storms from deserts in North Africa and China and
storms at sea). These episodic natural events, as well as events like the uncontrolled biomass burning
in Central America, are essentially uncontrollable and do not necessarily occur in all years.
      In-situ measurements provide evidence for the transport of anthropogenic PM from Asia on
Mt. Batchelor, OR (Jaffe et al., 2003, 052229). These data show sporadic but well correlated
increases in CO, O3, total Hg, and aerosol backscatter associated with air coming from Asia. The
ITCT-2K2 campaign also found evidence for the oxidation of SO2 to H2SO4 during trans-Pacific
transport of Asian emissions. If particulate SO42~ were to be formed in the polluted boundary layer
where it originated, it would likely be deposited prior to transport across the Pacific Ocean (Brock et
al., 2004, 156295). Thus, primary species emitted directly  and secondary species formed during
transport contribute to PRB  concentrations.  Satellite data have provided images to track clouds of
dust and pollution across the oceans and have been used for some quantitative estimation of the flux
of material leaving continents. Yu et al. (2008, 157168) used optical thickness data to estimate
December 2009                                 3-139

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column loadings from the MODIS along with satellite assimilated wind fields to estimate the
transport of PM from Asia. Three-dimensional, global-scale CTMs have also been used to estimate
intercontinental transport of PM pollution (UNCEC, 2007, 157078) and trans-Pacific transport of
mineral dust from Asian deserts (Fairlie et al., 2007, 141923) and the Sahara Desert (McKendry et
al., 2007, 156748).
      Estimates for the contribution of PBAP are highly problematic. Heald and Spracklen (2009,
190014) estimated the contribution of fungal spores to PM2.5 based on GEOS-Chem simulations of
mannitol, considered to be a unique tracer for fungal spores (Bauer et al., 2008, 189986).  They
estimated an annual mean contribution  of fungal spores to OC ranging from <0.1 (ig/m in the desert
Southwest to ~ 0.5 (ig/m3 in the more humid Southeast. It should be noted that these are model
derived estimates that still require evaluation against measurements in the U.S. They do, however,
provide the only quantitative estimates  of PBAP concentrations across the continental U.S.


3.7.1.1.   Estimates of PRB Concentrations in Previous Assessments

      Estimates of PRB concentrations reported in the 1996 PM AQCD (U.S. EPA, 1996, 079380)
and earlier PM AQCDs were based in large  measure on estimates by Trijonis et al. (1990, 157058)
for the National Acid Precipitation Assessment Program (NAPAP) as shown in Table 3-18. The
importance of different sources is likely to be quite different for natural background compared to
current conditions in the US, resulting in large changes in relations among different size fractions.
For example, PMi0_2.5 might be expected to  dominate under certain conditions in the absence of
primary and secondary PM2.5 from anthropogenic sources. Different approaches  for estimating PRB
concentrations in the western and eastern U.S. were taken in the 2004 PM AQCD (U.S. EPA, 2004,
056905).  Data obtained at IMPROVE monitoring sites in the western U.S. shown in Figure 3-84
were chosen as estimates of the distribution of daily average PRB concentrations in the West because
they were thought to be among the least likely influenced by regional pollution sources especially at
the upper end of the concentration distribution. This conclusion was  drawn from back trajectory
analyses and examination of the trace elemental composition at IMPROVE sites. Because of likely
unresolved contamination from pollution sources at other IMPROVE sites, it was recommended to
use averaged data from these sites throughout the West. Concentrations  distributions from 1988
through 2001 can be found in Appendix 3E  of the 2004 PM AQCD (U.S. EPA, 2004, 056905).
Median concentrations were ~3 (ig/m3.  Little interannual variability was observed below the 90th
percentile values. However, at the upper end of the concentration distribution substantial interannual
variability was observed due mainly to  forest fires and dust transport from Asian deserts. It was also
recognized that this method would likely overestimate PRB concentrations.
Table 3-18.   Estimates of annual average natural background concentrations of PM2.6 and P
            (ug/m3) from Trijonis et al. (1990, 157058). Estimates of PMi0.2.s were obtained
            subtraction.

                                 PM2.5                   PMlO                    PMlO-2.5
          East                     2-5                    5-11                    <1-9
         West                     1-4                     4-8                    <1-7
December 2009                                 3-140

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            Redwood  f
                fr*
                       C^nyotj'lan^s"}.
Figure 3-84.   IMPROVE monitoring site locations.

      Table 3-19 shows annual and quarterly average PM2.5 concentrations measured at the
IMPROVE sites shown in Figure 3-84 for 2004. Annual average concentrations tend to be slightly
higher in the East, particularly in Brigantine and Dolly Sods. When the data are broken down by
season, a more complex picture emerges. The highest concentrations in the East and Midwest are
found during the 3rd calendar quarter, whereas in the West highest quarterly averages can occur
during other quarters. As can also be seen from a comparison with values shown in Table 3-18, PM2.5
values measured in the East are much higher than the PRB concentration estimates by Trijonis et al.
(1990, 157058) for the NAPAP
December 2009
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Table 3-19.   Annual and quarterly mean PM26 concentrations (ug/m3) measured at IMPROVE sites in
            2004.

               Mean      January-March      April-June      July-September        October-December
EAST
Acadia
Brigantine
Dolly Sods
4.5
9.5
9.5
3.9
8.1
6.7
4.6
11.3
9.8
6.0
11.6
15.5
3.5
7.3
5.7
MIDWEST
Voyageurs
3.8
4.1
3.1
4.2
3.6
nor
Bridger
Canyonlands
Gila
Glacier
Redwood
2.1
2.6
2.9
4.8
3.5
1.2
2.2
2.0
4.6
2.7
3.1
3.2
4.0
4.2
3.6
2.8
2.9
3.8
5.3
3.7
1.3
2.1
1.8
5.0
3.9
      Thus, estimating daily average PRB concentrations in the eastern U.S. using observations is
highly problematic because of the widespread mixing of precursors and anthropogenic PM generated
in the East. Therefore, results from receptor modeling studies using PMF by Song et al. (2001,
036064) were used in the 2004 PM AQCD (U.S. EPA, 2004, 056905) for the East to separate
contributions from likely regional pollution sources from natural and imported pollution. The
"background" sources contribute about 7% to annual average PM2.5 concentrations at Underbill, VT
and about 12% at Brigantine, NJ, i.e., values between 1  and 2 ug/m3. These sites were chosen
because they were outside of urban areas making it easier to separate pollution from background
components. However, some contribution of regional anthropogenic pollution was still present.
      The PM Staff Paper (U.S. EPA, 2006, 157071) adopted a different approach for estimating
PRB concentrations. This approach separated out components mainly thought to be emitted by
regional pollution sources such as SO4 ~, which are obtained directly from observations at many
more IMPROVE sites than are shown in Figure 3-84, and to use the remaining PM components in
both the East and the West to estimate PRB. Removing regional pollution from data obtained at
IMPROVE sites is problematic as it involves assumptions about the relative contributions of regional
pollution and background sources. Although sulfate in the East is mainly produced by regional
pollution sources, it is not the only component with a regional pollution source. By comparison,
sulfate is a very minor component of PM2.5 in the West,  leading to substantial overestimates in
populated states like California. Annual mean estimates  in the continental U.S. ranged from
2.5  ug/m3 in the Central West (ID, MT, WY, ND, SD, CO, UT, NZ, AZ) to 5.2 ug/m3 for the
Southwest Coast (most of California), the latter value likely reflecting contributions from local, non-
sulfate pollution.
      In general, the methods outlined in both these documents are of limited utility for two reasons:
(1) they lack detailed spatial coverage across the whole  U.S.,  since both methods rely on monitoring
data that are limited both spatially and temporally; and (2) PM measurements from even the limited,
remote sites used in the previous estimates of PRB can not be completely devoid of contributions
from anthropogenic PM.  Because of these limitations, numerical modeling can provide superior PM
background estimates, as described just below.


3.7.1.2.   Chemistry Transport Models for Predicting PRB Concentrations

      CTMs can be used to estimate the PRB concentrations of atmospheric components including
PM using a "zero-out" approach in which anthropogenic emissions inside continental North America
are  set to zero while global biogenic emissions and anthropogenic emissions outside continental
December 2009                                3-142

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North America remain. Numerical modeling can provide more precision in the estimate of PRB PM
than measurements since even the most remote measurement sites like some of those in the
IMPROVE network (see the discussion in Section 3.7.1.1) will necessarily be affected by non-local
non-biogenic pollution, thereby confusing the contributions from these sources. Numerical models
are also capable of supplying estimates of PRB concentrations at much higher spatial and temporal
resolution than can be obtained by relying on measurements obtained at even the most remote
monitoring sites. In this approach, the monitoring data are used to evaluate the CTM's  performance.
      For this assessment, the global-scale circulation model GEOS-Chem was coupled with the
regional scale air quality model CMAQ (Section 3.6.2.2) to simulate one year of air quality data over
the CONUS in two series of runs, the first annual series with all anthropogenic and biogenic
emissions included and the second annual series with the zero-out approach employed.
      The global-scale scale circulation model was set up as follows.  GEOS-Chem, version 7, was
used, with modifications to include aromatic and biogenic SOA formation; emissions were computed
from a variety of sources including the Global Emissions Inventory Activity (GEIA) (Benkovitz et
al., 1996,  156267), and Emissions Database for Global Atmospheric Research, version 2 (EDGAR)
(Olivier et al., 1996, 156828: Olivier et al., 1999,  1568291
      Particularized emissions in specific areas used the European Monitoring and Evaluation
Program (EMEP) for Europe (Auvray and Bey, 2005, 156237). BRAVO (Kuhns and Knipping,
2005, 156663) for Mexico, and Streets et al. (2006, 157019) for Asia.  Emissions from these studies
were supplemented with data from Martin et al. (2002, 089380) for additional NOX emissions from
biofuels, lightning, and ship traffic, Bond et al.  (2004, 056389) for global primary organic aerosols,
and Cooke et al. (1999, 156365) and Park et al. (2003, 156842) for U.S. primary  organic aerosols.
Biomass burning emissions are not climatological, but were computed with GFEDv2 (Giglio et al.,
2006, 156469; van der Werf et al., 2006, 157084); monthly  values computed using active fire
observations from MODIS; global dust fields computed  off-line using GOCART (see emissions from
DEAD: http://dust.ess.uci.edu/dead/) to make annual adjustments to photolysis rates and
heterogeneous-phase chemistry.
      The regional CTM was set up as follows. CMAQ, version 4.7, (excluding the dynamic coarse
mode updates) was used with the SAPRC_99 chemical mechanism and AERO5 aerosol module;
emissions were processed through SMOKE (http://smoke-model.org). version 2.4, based on the 2004
projections from the NEI with specific CEM, biogenics,  and fire updates; MM5, version 3.7.4, was
used with the Asymmetric Convective Mixing,  version 2.2,  PEL scheme; and data nudging was used
to analyze fields for  winds and temperature.


      Model Evaluation

      Details from evaluations of the performance of a number of CMAQ applications are given in
Arnold et  al. (2003, 087579). Eder and Yu (2006,  142721). Appel et al. (2005, 089227). and Fuentes
and Raftery (2005, 087580).
      In an annual simulation series for 2002 using CMAQ, version 4.6.1, in two 12-km domains for
the CONUS (Figure 3-85), predicted concentrations of summertime particulate SO4, often a major
determinant of surface-layer PM concentrations, were well-predicted by CMAQ at a 12-km grid
spacing, to within a factor of 2 at nearly every point of comparison and with R2 >0.8 across all three
national networks (CASTNet, IMPROVE and CSN); a more detailed  description is included in the
2008 NOxSOx ISA (U.S. EPA, 2008, 157074). This result for CMAQ, version 4.6.1, for 2002 tracks
the generally well-predicted SO42~ concentrations found  in most earlier CMAQ evaluations: see
Mebust et al. (2003,  156749). Eder and Yu (2006, 142721).  and Tesche et al. (2006, 157050). Since
particulate SO42~ concentrations are strongly a function of precipitation, care must be taken to ensure
that the meteorological solution driving individual CMAQ chemical applications produces
precipitation fields with low bias as discussed by Appel et al. (2008, 155660).
December 2009                                3-143

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                                   2002ac m»l2«3 izkmE SCM lor June lo August 2002
                               a  IMPROVE (2002ac me12v33 lEkmE)
                               fl  STN(2002ac mat2v33 12
                                 CASTNet{2002ac me!2v33 I
                            Ctl
                            o .
                                                        Monthly Average
                                                          SO4 ( ug<'m3)

IMPROVE
STN
CASTNet
CQRfl HWSE
096 084
0,83 1 57
0.9? 0 83
NMB
-11 7
0,4
-86
NME
172
201
125
                                             Observation
Figure 3-85.   12-km EUS Summer S042~ PM.  Each data point represents a paired monthly
              averaged (June/July/August) observation and CMAQ prediction at a particular
              IMPROVE, STN, and CASTNet site. Solid lines indicate the factor of 2 around the
              1:1 line shown between them.

      Wintertime participate NO3~ (Figure 3-86) and total NO3 (HNO3 + participate NO3~) (Figure
3-87) concentrations are predicted as well by CMAQ; however, NO3~ is a pervasively difficult
species to measure and model. Still, at the CASTNet nodes where the total NO3~ concentrations are
higher than they are at all but a few of the remote IMPROVE sites, CMAQ predicts concentrations
for nearly every node to within a factor of 2 and with an R2 >0.8.
      A "base case" in which conditions for 2004 including all the anthropogenic and natural
sources both within and outside of continental North America was run for comparison with
measurements. APRB simulation was also run by shutting off the anthropogenic sources of primary
PM and precursors to secondary PM inside continental North America.
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Figure 3-86   12-km EUS Winter NOs" PM. Each data point represents a paired monthly
             averaged (December/January/February) observation and CMAQ prediction at a
             particular IMPROVE and STN site. Solid lines indicate the factor of 2 around the
             1:1 line shown between them.
                               20UZ»:_mcl2v33_12kmE TN03 (or Of cf mtwr to I rtmjarj ZOQ2
Figure 3-87.   12-km EUS Winter total nitrate (HN03 + total particulate N03~).  Each data point
             represents a paired monthly averaged (December/January/February) observation
             and CMAQ prediction at a particular CASTNet site. Solid lines indicate the factor
             of 2 around the 1:1 line shown between them.
December 2009
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      Figure 3-88 and Figure 3-89 show monthly average concentrations, and Figure 3-90 and
Figure 3-91 show 24-h avg concentration distributions for 2004 predicted by CMAQ for the base
case and for PRB. Measurements are also included for the five western and four eastern/midwestern
IMPROVE sites shown in Figure 3-84. Wildfires could have affected the grid cell containing the
midwestern Voyageurs site resulting in the high PRB values found for the July average compared to
the PRB values for the rest of the year. The "base case" simulations tend to underestimate
concentrations throughout most western sites as shown in Figure 3-89 and Figure 3-91. These
underestimates are still within the range of a few (ig/m3. However, the base case simulation also
greatly over-predicts PM2.5 concentrations at the upper end of the distribution at the Redwoods site
(Figure  3-91). This over-prediction results from emissions from wildfires in northern California that
are included in the grid cell containing the Redwoods site, but may not have affected the site.
However, wildfires indicated by MODIS would have affected other areas either close to these sites
or could have affected other locations in between the IMPROVE sites. The simulated monthly
average PRB concentrations in the east/midwest range from a minimum of 0.6 (ig/m3 at Acadia
National Park (NP) in July to 3.7 (ig/m3 at Voyageurs NP in July. However, most values are
<1 (ig/m3. The monthly average PRB concentrations calculated for the West tend to be lower than for
the East and range from 0.2 (ig/m3 at Bridger and Glacier NPs in January and February, respectively,
to 8.7 (ig/m3 at Redwoods NP in November. Excluding values at Redwoods NP which greatly exceed
measurements, the highest monthly average concentration was 3.7 (ig/m3 at Voyageurs NP in the
East/Midwest and 2.4 (ig/m3 at Gila NP in the West.
                      Acadia
                 Brigantine
          20

          16;

          12

           8
      20

      16

      12

       8

       4
              1  2 3  4 6  6 7  8  9 10 11 12
          1  2  3  4  5  6  7  8  9  10 11 12

                      Month
                     Dolly Sods
                 Voyageurs
          20

          16

          12

           8

           4

           0
              1  2  3  4  6 6  7  8  0  10 11 12

                          Month
      20

      16

      12

       8

       4

       0
                                             • Base
          1  2  3  4 E  6 7  8 9 10 11  12

                      Month

         ,-PRB
Figure 3-88.   Monthly average of PM2.s concentrations measured at IMPROVE sites in the East
              and Midwest for 2004. Also shown are distributions of PM2.s concentrations
              calculated by CMAQ for the base case and for PRB.
December 2009
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                         Bridgar
                                              Canyonlands
          I
12
10
8
6
4
2
0
 12
 10
 8
i
1 6


 2
                                                    1  2  3  4 5  6  7 8  9  10 11  12
                                                                Month
                         Gila
                                                 10
                                                 8
                                                 6
                                                 4
                                                 2
                1  2  3 4  5 6 7  8  9 10 11 12
                             Month
                                       1  2 3 4  6  6 7  8  8 10 11 12
                                                  Month
                            I
                  12]
                  10-
                  8
                  e
                  4
                  2
                                  1  2  3 4  E  8 7  8  8 10 11  12
                                             Month
                                       •Monltorcd -^•^Bws
                                                        PRB
Figure 3-89.   Monthly average of PM2.s concentrations measured at IMPROVE sites in the West
              for 2004. Also shown are distributions of PM2.s concentrations calculated by
              CMAQ for the base case and for PRB.
December 2009
                             3-147

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                    Aeadia
                                                           Brigantino
  *•••••
  I
40
35
30
25
20
16
10
 6
 0
        mln 10 20 30 40 60 60 70 60 90 86 88 m«
                                                   mlnlO 20 30 40 60 60 70 80 90 96 99mix
                                                               PnmUlt
                    Dolly So*
                                                           Voyigwra
        mln 10 20 30 40 60 60 70 90 90 86 88mm
                                                      10 20 30 40 60 60 70 80 90 86 99 m«
                                                                Pmindli
                                                    •PRB
Figure 3-90.   Distribution of PM2.s concentrations measured at IMPROVE sites in the East and
             Midwest for 2004. Also shown are distributions of PM2.s concentrations
             calculated by CMAQ for the base case and for PRB.
December 2009
                                    3-148

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                          Brldger
                                                               Canyonlindi
              mn 10 20 30 40 50 60 70 80 90 96 99 max
                                                       10 20 30 40 50 60 70 80 90 96 99
                           Oil!

              mln 10 20 30 40 60 60 70 80 80 86 89 mn
        mln 10 20 30 40 50 60 70 80 80 86 88 mix
                                 mln 10 20 30 40 60 80 70 60 90 96 99mm
                                      • Monitored —•— DIM
                                                       • PRB
Figure 3-91.   Distribution of PM2.s concentrations measured at IMPROVE sites in the West for
              2004. Also shown are distributions of PM2.s concentrations calculated by CMAQ
              for the base case and for PRB. Note the scale change on the y-axis for Redwoods
              NP.

      Table 3-20 gives the annual and quarterly average CMAQ predictions at IMPROVE sites for
the "base case" and the ratio of CMAQ predictions to the measured concentrations at those sites in
2004. CMAQ performance for the annual average concentrations and most of the seasonal averages
is very good in the East and Midwest, generally falling within 35%. In the West,  CMAQ's prediction
of PM2.5 mass averages at these remote sites is generally too low in all seasons, often by 50%. Air
quality model predictions in the mountainous West are often not as good as those over the flatter
December 2009
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terrain in the East and Midwest because the model's grid spacing (36 km in this case) smoothes over
significant variation at the surface that results in differences at such remote sites. However, the
model's trend relative to the geospatial difference is correct: the predicted PM2.5 concentrations are
lower at the western sites than they are at the eastern sites, just as the measurements are. Table 3-21
shows corresponding annual and quarterly mean PRB PM2 5 concentrations at IMPROVE sites.


Table 3-20.  Annual and quarterly mean PM2 6 concentrations (ug/m3) for the CMAQ "base case" at
            IMPROVE sites in 2004.

Annual; mod/obs
Jan-March; mod/obs
Apr-Jun; mod/obs
Jul-Sep; mod/obs
Oct-Dec; mod/obs
EAST
Acadia
Brigantine
Dolly Sods
4.7; 1.04
10.2; 1.07
9.8; 1.03
5.6; 1.44
10.9; 1.35
8.3; 1.24
4.0; 0.87
10.3; 0.91
8.6; 0.88
4.6; 0.77
10.2; 0.88
14.0; 0.90
4.6; 1.31
9.4; 1.29
8.0; 1.40
MIDWEST
Voyageurs
4.0; 1.05
4.9; 1.19
2.2; 0.71
3.9; 0.93
4.9; 1.36
nor
Bridger
Canyonlands
Gila
Glacier
Redwood
1.6; 0.76
1.6; 0.62
1.6; 0.55
2.2; 0.45
4.6; 1.31
1.3; 1.08
1.9; 0.86
1.4; 0.70
1.8; 0.39
4.0; 1.48
1.6; 0.52
1.4; 0.44
2.2; 0.55
2.1; 0.50
3.0; 0.83
1.8; 0.64
1.5; 0.52
1.7; 0.45
2.1; 0.40
2.9; 0.78
1.7; 1.30
1.6; .76
1.1; 0.61
2.8; 0.56
8.4; 2.15
      Table 3-22 illustrates CMAQ predictions of seasonal variation in the base case PM2.5
concentrations across regions of the CONUS, while Table 3-23 shows CMAQ predictions of the
seasonal variation in regional PRB PM2.5 concentrations. Highest base case PM2 5 concentrations
were observed for the Northeast, Southeast, and industrial Midwest, with highest concentrations
during the fall and winter (and comparably high concentrations in the summer for the Industrial
Midwest). PRB PM2 5 concentrations were highest on an annual basis in the Southeast, and peaking
during the winter. In the summer, PRB PM2 5 is roughly comparable for the Northwest and Southern
California and elevated, but slightly lower for the Southwest. These results also likely indicate the
influence of sources that are more strongly related to hot and dry  conditions such as wildfires and
dust suspension.
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Table 3-21.   Annual and quarterly mean PM26 concentrations (ug/m3) for the CMAQ PRB simulations
              at IMPROVE sites in 2004.

Annual
January -March
April-June
July-September
October-December
EAST
Acadia
Brigantine
Dolly Sods
0.70
0.77
0.79
0.76
0.86
0.88
0.76
0.91
0.83
0.65
0.70
0.75
0.65
0.63
0.66
MIDWEST
Voyageurs
1.2
0.83
0.91
2.0
0.93
nor
Bridger
Canyonlands
Gila
Glacier
Redwood
0.57
0.49
0.74
0.91
2.8
0.33
0.38
0.42
0.36
2.4
0.57
0.54
1.4
0.87
1.5
0.76
0.68
0.80
1.1
1.1
0.61
0.35
0.32
1.3
6.1

Table 3-22.   Annual and quarterly mean of the CMAQ-predicted base case PM2 5 concentrations
              (ug/m3) in the U.S. EPA CONUS regions in 2004.
                     Annual     January-March
 April-June
July-September
October-December
Northeast
                       9.76
                                    10.74
                                                     8.38
                                                                     9.55
                                                                                          10.38
Southeast
                      10.05
                                    12.28
                                                     7.72
                                                                     9.78
                                                                                          10.42
Industrial Midwest
                      11.38
                                    12.22
                                                     9.37
                                                                     11.8
                                                                                          12.00
Upper Midwest
                       6.70
                                     8.83
                                                     4.95
                                                                     5.34
                                                                                           7.67
Southwest
                       3.30
                                     4.08
                                                     2.77
                                                                     3.31
                                                                                           3.03
Northwest
                       2.72
                                     2.49
                                                     2.21
                                                                     2.71
                                                                                           3.44
Southern California
                       4.43
                                     4.64
                                                     3.93
                                                                     4.34
                                                                                           4.82
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Table 3-23.   Annual and quarterly mean of the CMAQ-predicted PRB PM2 5 concentrations (ug/m3) in
            the U.S. EPA CONUS regions in 2004.


                              Annual      January-March    April-June    July-September October-December

Northeast                         0.74           0.85          0.78          0.67          0.68

Southeast                         1.72           2.43          1.41          1.41          1.64

Industrial Midwest                    0.86           0.89          0.89          0.94          0.73

Upper Midwest                      0.84           0.79          0.93          0.99          0.66

Southwest                         0.62           0.61          0.76          0.70          0.40

Northwest                         1.01           0.48          0.81          1.42          1.32

Southern California                    0.84           0.54          0.92          1.21          0.67
3.8.  Issues in Exposure Assessment for PM and  its

Components

      The purpose of this section is to present the latest exposure assessment studies to characterize
the exposure of individuals and populations to PM of ambient origin. Such information will aid the
interpretation of epidemiologic studies described in subsequent chapters of this ISA. This
section includes descriptions of modeling and monitoring techniques used to capture personal PM
exposure, observations reported in the literature at various relevant spatial scales, observations
related to PM composition and PM in a mix of copollutants, and the effect of exposure estimates on
epidemiologic results. Attention is given to use of community-based monitors at urban spatial scales
and use of personal and microenvironmental exposure data to present how each metric can be used
in exposure assessment and what errors and uncertainties exist for each approach. Understanding of
exposure errors is important because exposure error can potentially bias an estimate of a health effect
endpoint, or increase the size of confidence intervals around a health effect estimate. Typically,
exposure error biases analyses of health effects towards the null (i.e., no relationship between
exposure and health effect).
      The information presented in this section builds upon the key findings of the 2004 PM AQCD
(U.S. EPA, 2004, 056905). One key finding was that separation of total PM exposures into ambient
and nonambient components reduces potential uncertainties in the analysis and interpretation of PM
health effects data. At the time of the 2004 PM AQCD (U.S. EPA, 2004, 056905). one study reported
that individual daily values of both the total and nonambient personal PM exposure were poorly
correlated with the daily ambient PM concentrations, while individual daily values of ambient PM
exposure and daily ambient PM concentrations were highly correlated. In pooled studies (different
subjects measured on different days), individual, daily values of the total PM exposure were
generally shown to be poorly correlated with the daily ambient PM concentrations. In longitudinal
studies (each  subject measured for multiple days), individual, daily values of the total PM personal
exposure and the daily ambient PM concentrations were found to be highly correlated for some, but
not all, subjects. Using the PTEAM study data, the 2004 PM AQCD (U.S. EPA, 2004, 056905) also
analyzed exposure measurement errors in the context of time-series epidemiology to show that the
error introduced by using ambient PM concentrations as a surrogate for ambient PM exposures
negatively biases the estimation of health risk coefficients by the ratio of ambient PM exposure to
ambient PM concentration. However, it was concluded that the health risk coefficient determined
using ambient PM concentrations provides the correct information on the change in health risks that
would be produced by a change in ambient concentrations.
      Personal exposure to PM can vary considerably depending on PM size and composition,
source strength and proximity, season, time of day, region of the country, population density of the
environment,  personal activity patterns, and ventilation of indoor environments. Table A-58 of
Annex A, which summarizes findings from U.S. panel studies of personal exposure to PM with no
December 2009                                 3-152

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indoor sources published between 2002 and 2008 broken down by region of the country, illustrates
this variability.  For example, Table A-58 presents 24-h personal PM2.s exposures that range from
roughly 1-55 ug/m3 with highest exposures in the southwest and northeastern regions of the country
and during the summer season. Section 3.8 is designed to present current theory and field results
regarding exposure to PM. To illustrate the concept of personal exposure within various
microenvironments, a general exposure model is presented in Section 3.8.1. New developments in
techniques for measuring personal and indoor PM are presented in Section 3.8.2, followed by
exposure modeling techniques in Section 3.8.3. In Section 3.8.4, exposure assessment field studies in
the literature are presented. Attention is given to ambient exposure over multiple spatial scales
including near-road, in-vehicle, and indoor environments. Section 3.8.5 presents issues related to PM
composition and PM in multipollutant mixtures. Finally, implications of exposure assessment issues
for epidemiologic studies are presented in Section 3.8.6.


3.8.1.    General Exposure Concepts

      A theoretical model of personal exposure is presented to highlight what is measurable and
what uncertainties exist in this framework. An individual's time-integrated total exposure to airborne
PM can be described based on a compartmentalization of the person's activities during a given time
period:

                                        ET  = \Csdt

                                                                                   Equation 3-3

where ET = total exposure over a time period of interest, C, = airborne PM concentration at
microenvironmentj, and dt = portion of the time-period spent in microenvironmentj. Equation 3-3
can be decomposed into a microenvironmental model that accounts for exposure to PM of ambient
(Ea) and nonambient (Ena) origin of the form:
                                                                                   Equation 3-4

      Figure 3-92 illustrates Equation 3-4. Examples of ambient PM sources include industrial and
mobile source emissions, resuspended dust, biomass combustion, and secondary formation.
Examples of nonambient sources include smoking, cooking, home heating, cleaning, and indoor air
chemistry. PM concentrations generated by ambient and nonambient sources are subject to spatial
and temporal variability that can affect estimates of exposure and resulting health effects. Exposure
factors affecting interpretation of epidemiology are discussed in detail in Section 3.8.6.
December 2009                                 3-153

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                  	in

                    Ambient
                   Exposure

                    Ambient
                  PM, C while
                    Outdoors

                    Ambient
                    PMthat
                    Infiltrates
                    Indoors
 Total Personal
Exposure to PM
             PEM
    I	

Nonambient
  Exposure

Indoor Sources
   (cooking,
   cleaning)
                       Personal Sources
                          (smoking,
                           hobby)
                                        Source: Adapted with permission of Nature Publishing Group from Wilson and Brauer (2006, 088933).

Figure 3-92.   Model of total personal exposure to PM as a function of ambient and nonambient
              sources.

      This assessment focuses on the ambient component of exposure because this is more relevant
to the NAAQS review. Ea can be decomposed into the fraction of time spent in various outdoor and
indoor microenvironments (Wallace et al., 2006, 089190: Wilson et al., 2000, 010288):
                                                                                   Equation 3-5

where/= fraction of the relevant time period (equivalent to dt in Equation 3-2), subscript o = index
of outdoor microenvironments, subscript / = index of indoor microenvironments, subscript o,i =
index of outdoor microenvironments adjacent to a given indoor microenvironment /', and F^j =
infiltration factor for indoor microenvironment z. Equation 3-5 is subject to the constraint S/0 +
1/i = 1, and each term on the right hand side of the equation has a summation because it reflects
various microenvironmental  exposures. Here, "indoors" refers to being inside any aspect of the built
environment, e.g., home, office buildings, enclosed vehicles (automobiles, trains, buses), and
recreational facilities (movies, restaurants, bars). "Outdoor" exposure can occur in parks or yards, on
sidewalks, and on bicycles or motorcycles.
      Finf represents the equilibrium fraction of the PM concentration outside the microenvironment
that penetrates inside the microenvironment and remains suspended. It is a function of the
microenvironmental air exchange characteristics and the particle properties. Assuming steady state
conditions, the infiltration factor is a function of the penetration, P, of PM (a fractional quantity
representing the portion of outdoor PM that passes through the building envelope), the air exchange
rate, a, of the indoor microenvironment, and the rate of PM loss, k, within the indoor
microenvironment: Fmf = Pal(a+K). Determination of Ea can be complicated by PM loss through
chemical and physical processes in microenvironments,  and the composition of PM can be modified
during infiltration of outdoor air into microenvironments (Meng et al., 2007, 194618:  Sarnat et al.,
2006, 089166).
      In the context of interpreting epidemiologic studies of the effects of ambient pollutants on
human health, the association between Ea and concentrations from a central site monitor, Ca, is more
relevant than the association between ET and Ca because nonambient PM is uncorrelated with Ca, as
discussed in Section 3.8.4. In ecologic studies of large panels  or cohorts, Ca is often used in lieu of
outdoor microenvironmental data to represent these exposures based on the availability of data. Thus
it is often assumed that C0 =  Ca and that the fraction of time spent  outdoors can be expressed
cumulatively as/0; the indoor terms still retain a summation because infiltration differs among
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different microenvironments. Under these assumptions, an individual's exposure to ambient PM,
first given in Equation 3-5, can be re-expressed as a function of Ca. The following approximation has
been employed in the literature to describe ambient exposure based on these assumptions (Wallace et
al., 2006, 089190: Wilson and Brauer, 2006, 088933: Wilson et al., 2000, 010288):
                                                                                 Equation 3-6

Particle size, particle composition, meteorology, urban and natural topography, and other factors
determine whether or not Equation 3-6 is a reasonable approximation for Equation 3-5. Errors and
uncertainties inherent in the use of Equation 3-6 in lieu of Equation 3-5 are described in
Section 3.8.6 with respect to implications for epidemiology. If concentration measured at a central
site monitor is used to represent ambient concentration, then a, the ratio between personal exposure
to ambient PM and the ambient concentration of PM, can be defined as:
                                                                                 Equation 3-7

If the assumptions forming the basis for Equation 3-6 are valid, then a is the proportionality factor in
Equation 3-6:
                                                                                 Equation 3-8

a varies between 0 and 1. If a person's exposure occurs in a single microenvironment, the ambient
component of a microenvironmental PM concentration can be represented as the product of the
ambient concentration and F-^. Wallace et al. (2006, 089190) note that time-activity data and
corresponding estimates of Finf for each microenvironmental exposure are needed to compute an
individual's a with accuracy. If significant local sources and sinks are not captured by central  site
monitors, then the ambient component of outdoor air must be estimated using dispersion models,
land use regression (LUR) models, receptor models, fine scale CTMs or some combination of these
techniques. Modeling methods are described in Section 3.8.3.


3.8.2.    Personal and Microenvironmental Exposure Monitoring

      The purpose of this section is to present new discoveries related to measuring
microenvironmental PM concentrations or personal exposure to PM. A review of over 100 personal
and microenvironmental PM exposure studies published since 2002 (see Table A-58 of Annex A)
reveals that the majority of the monitoring techniques in use were previously reviewed in the 2004
PM AQCD (U.S. EPA, 2004, 056905) for PM. Detailed descriptions of these methodologies are
provided in that document and therefore will not be repeated in this document. The following
sections will include only findings from 2002 or later regarding monitoring and modeling
methodologies in common use and significant advancements in understanding the capabilities and
limitations of these methods for assessment of PM exposure.


3.8.2.1.   New Developments in Personal Exposure Monitoring  Instrumentation

      Current personal exposure sampling methodology consists largely of integrated filter sampling
using a cyclone or personal exposure monitor (PEM) to achieve a cut point at a desired particle size.
This method of sampling facilitates speciation work because the filters can be archived for chemical
and gravimetric analysis. Additionally, light scattering aerosol detection  instruments, such as the
personal DataRam (pDR) and SidePak personal aerosol monitor have seen some use in personal
PM2.5, PMi0, and PMi monitoring (e.g., Lewne et al., 2006,  090556: Wallace et al., 2006, 088211).
Several researchers have noted that relative humidity causes overestimation of the particle mass in
December 2009                                 3-155

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light-scattering personal exposure monitors (e.g., Lowenthal et al., 1995, 045134; Ramachandran et
al., 2003, 195017); a correction factor has been applied to concentrations to address this issue. In the
DEARS, Williams et al. (2008, 191201) attempted to reduce humidity of the sample stream by
placing a drying column upstream of the pDR's detector. Although this addressed the humidity issue,
the drying column occasionally released particles and therefore caused artificial concentration peaks.
For this reason, Williams et al. (2008, 191201) determined that the humidity correction approach is
preferable.
      One area of further development  is in personal sampling of the thoracic and respirable particle
size distribution. Variations of the cascade impactor have been developed for personal sampling and
tested for use in field studies (Case et al., 2008, 155149; Lee et al., 2006, 098249; Singh et al., 2003,
156088). The model developed and tested by Lee et al. (2006, 098249) operates with a 1-um cut
point and therefore can characterize respirable particles well. The Case et al. (2008, 155149) two-
stage cascade impactor separated PM10_2.5 from PM2.5 for personal monitoring and sampled within ±
20% of a reference method. Hsiao et  al. (2009, 191001) developed a mini-cyclone with a 1 urn or
0.3 um cut point for sampling accumulation mode and UFPs. The Personal Cascade Impactor
Sampler (PCIS) has the capability to  sample down to a cut point of 250 nm (Singh et al., 2003,
156088). For PM2.5, the difference between the PCIS and the MOUDI cascade impactor was 11%,
while  the difference between the PCIS and the SMPS-APS was only 2%. Differences between the
PCIS and the MOUDI  for PM25 species compared with the MOUDI was generally higher:  11% for
SO42~, 22% for NO3~, 19% for EC, and  94% for OC. Mass was overestimated by 3%, 16%, and 31%
for PMi_o.5, PM0.5_o.25, and PM0.25, respectively, when compared with the SMPS-APS.  Similarly, Case
et al. (2008, 155149) found a mass difference ranging from -11 to +10% for PMi0_2.5 with the
Personal Respirable Particulate Sampler (PRPS), and Lee et al. (2006, 098249) found a mass
difference of-6 to 0%  for PM25 and -6  to -1% for PMi0 when comparing results from this device
with those from the PEM.  Leith et al. (2007, 098241) redesigned the Wagner-Leith passive sampler
for measuring PMi0_2.5. In this work, the difference between a PMi0_2.5 FRM and the co-located
passive sampler was within 1 standard deviation of concentrations measured by the FRM samplers.
      A number of personal PM monitors are under development as part of the National Institutes of
Health Genes, Environment, and Health Initiative (http://www.gei.nih.gov/exposurebiology/
program/sensor.asp). Funded projects for miniature personal monitors include a platform that records
real-time BC and PM concentrations  and archives PM for further analysis, a badge containing a
sensor array that detects several compounds found in diesel PM, a micro-nephelometer recording
PM and endotoxin exposure, a complementary metal-oxide-semiconductor (CMOS) fitting in the
nose to measure allergen PM, and a micro-thermofluidic nanoparticle sensor. The mini-cyclone cited
above was designed to operate upwind  of the micro-thermofluidic sensor (Hsiao et al., 2009,
191001). LeVine et al.  (2009, 192091) and Schwartz et al. (2008, 192094) described use of the
CMOS technology for real-time DNA detection. Mulchandani et al. (2001, 191003) reviewed
amperometric biosensors used for organophosphate pesticide detection that are the basis of the diesel
detection badge; several additional articles have been published by this group that describe
applications of amperometric sensors.


3.8.2.2.   New Developments in Microenvironmental Exposure Monitoring
          Instrumentation

      The majority of  developments  since the 2004 PM AQCD (U.S. EPA, 2004, 056905) regarding
microenvironmental PM characterization have involved real-time instrumentation in the UFP size
range. Because these methods  are also used for ambient sampling, they are described in Section 3.4
and in Annex Table A-59.
      New developments in microenvironmental sampling for exposure assessment have also
included construction,  testing, and implementation of mobile environmental sampling laboratories
for PM mass, particle count, and composition, as well as other criteria pollutants (CO, SO2, NO2,
O3). These mobile laboratories typically contain a suite of real-time equipment with short sampling
intervals (e.g., 1-10 min), such as an  SMPS with CPC, APS,  laser photometers, and aethalometers
for aerosols; monitors  for the gaseous criteria pollutants; a weather station for meteorological
variables; and a Global Positioning System (GPS) for position. Videotape or journal observations are
sometimes logged simultaneously to track local on-road sources of pollution. One key application of
mobile laboratory technology is assessment of the outdoor microscale environments and in-vehicle
microenvironments on roadways for determining exposure during on-road transportation (Pirjola et
December 2009                                 3-156

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al., 2004, 117564; Sabin et al, 2005, 087728; Weijers et al, 2004, 104186; Westerdahl et al, 2005,
086502). For instance, Sabin et al. (2005, 087728) used videotape records to determine whether BC
detected on a school bus was the result of local outdoor sources from other vehicles or
"self-pollution" from the school bus's own engine exhaust. Westerdahl et al. (2005, 086502) used the
GPS time series to determine that minima in the UFP time series corresponded to passage through
residential areas of Long Beach and Pasadena, in contrast to the pollution spikes observed along
highways. Studies have also shown that detection of PM from vehicle exhaust could be improved
through use of combined measurement results to improve statistical analysis (Ntziachristos  and
Samaras, 2006, 116722).
3.8.3.    Exposure Modeling
      This section describes a variety of techniques used to model PM exposure. Many of these
methods are used in combination to link ambient PM levels in the atmosphere or source
characteristics to human exposure among individuals or sample populations. Recent developments in
exposure modeling are described in this subsection, and errors and uncertainties of these approaches
are described in Section 3.8.6.2.


3.8.3.1.   Time-Weighted Microenvironmental Models

      An individual's exposure is dictated by his or her activity patterns, as modeled by/ and/ in
Equation 3-5. Anumber of panel studies have tracked subject exposures using questionnaires, time-
activity diaries, or global positioning systems(e.g., Cohen et al., 2009, 190639; Elgethun et al., 2003,
190640; Johnson et al.,  2000, 001660; Olson and Burke, 2006,  189951; Wallace et al., 2006,
089190). In many cases, the time-activity tracking is performed in conjunction with personal
exposure and/or indoor and outdoor PM concentration monitoring to estimate overall PM exposure.
Wu (2005, 086397) described a microenvironmental model of total personal exposure:

                                  ET=fohC0+foaCa+flCl
                                                                                  Equation 3-9

where/,;, = fraction of time spent outdoors at home,/a = fraction of time spent outdoors away from
home, C0 = PM concentration outside the home, and C, = indoor PM concentration. In Equation 3-9,
ET can be  calculated based on time-activity diary data and time-resolved PM concentration
measurements. ET can be expressed as a time-resolved value or cumulatively over a time period of
interest using this formulation. In this model, ambient and nonambient exposure cannot be separated
because it incorporates indoor concentrations that are a function of both ambient and nonambient
sources. Additionally, Equation 3-9 distinguishes ambient concentration measured at a monitor from
that measured immediately outside the home. Liu et al. (2003, 073841) found that this model
predicted elderly exposures adequately but was a poor predictor of PM2.5 exposure for asthmatic
children. Wu et al. (2005, 086397) point out that this may be due to lack of availability of the
children's time-activity  data in school where children spend a substantial portion of their day. In a
study of school children's exposure patterns, DeCastro et al. (2007, 190996) computed odds ratios of
a panel subject's  location within a given microenvironment using multivariate logistic models of the
indoor school, indoor home, and outdoor microenvironments. They found that (1) the city of
residence was a significant predictor of being indoors at school; (2) having an afterschool job was a
significant predictor of being indoors at home; and (3) age and having an afterschool job were
significant predictors of being outdoors. The results of the DeCastro et al. (2007, 190996) study were
designed to predict/ and/ in exposure modeling.
      A second approach proposed by Wu et al.  (2005, 086397) is similar in formulation to Equation
3-5 because it computes ambient PM exposure by considering the amount of outdoor PM infiltrated
indoors. This version also incorporates  C0 and Ca:
December 2009                                 3-157

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                                Ea=fohC0+foaCa+ftFMC0
                                                                                  Equation 3-10

Equation 3-10 differs from Equation 3-5 because it accounts for concentrations immediately outside
the building rather than considering all outdoor exposures to be a function of that measured at a
community monitor. Factors influencing the contribution of Ea to ET may include sample population
characteristics, location of a site for microenvironmental monitoring, seasonal trends in PM
concentration, and regional differences affecting ambient concentration and infiltration.
      Regression based approaches can also be incorporated into time-weighted microenvironmental
modeling. Chang et al. (2003, 053789) used data from the Scripted Activity Study and the Older
Adults Study, both conducted in Baltimore in  1998 and  1999, to compute total personal exposure
based on time-weighted microenvironmental exposures for each panel subject:
                            ET =
                                                                                  Equation 3-11
where ME = microenvironment (indoor or outdoor), /? = regression coefficient reflecting the
accuracy of the exposure estimate for a given microenvironment,^ = fraction of time performing an
activity k, and Ck = personal exposure while performing activity k. In this work, Chang et al. (2003,
053789) tested the models with hourly  personal exposure data, hourly ambient  concentration data,
and daily ambient concentration data. The study found that time-activity data improved  estimates of
24-h PM2.5  exposure in comparison with using 24-h ambient PM2.5 data, but the use of hourly
ambient data was comparable to personal microenvironmental data in estimating exposure. When
using ambient concentration data, /? reflected infiltration for the indoor microenvironmental
estimates for a sample population. Using a similar activity-based exposure modeling approach for a
panel study in Seattle from 1999-2002, Allen et al. (2004, 190089) found that subjects' PM
exposures were best represented by modeling ambient and nonambient exposures separately because
ambient PM personal exposure was well correlated with PM concentration at central site monitors,
while nonambient PM exposure was  not.


3.8.3.2.  Stochastic Population  Exposure Models

     Population-based methods, such  as the Air Pollution Exposure (APEX), Stochastic Human
Exposure and Dose Simulation (SHEDS), and EXPOLIS (exposure  in polis,  or cities) models,
involve stochastic treatment of the model input factors
(http://www.epa.gov/ttn/fera/human  apex.html; (Burke et al., 2001, 014050; Kruize et al., 2003,
156661). These are described in detail in Annex 3.7 of the 2008 NOX ISA (U.S. EPA, 2008, 157073).
Stochastic models utilize distributions of pollutant-related and individual-level  variables, such as
ambient and local PM concentration  source contributions and breathing rate, respectively, to
compute the distribution of individual exposures across the modeled population. Using distributions
of input parameters in the model framework rather than point estimates allows the models to
explicitly incorporate uncertainty and variability into  exposure estimates (Zidek et al., 2007,
190076). These models estimate time-weighted exposure for modeled individuals by summing
exposure in each microenvironment visited during the exposure period. The models also have the
capability to estimate received dose through a dosimetry model. The initial set of input data for
population  exposure models is ambient air quality data, which may come from  a monitoring network
or model estimates. Estimates of concentrations in a set of microenvironments are generated either
by mass balance methods  or microenvironmental factors. Microenvironments modeled include
residential indoor microenvironments;  other indoor microenvironments, such as schools, offices, and
public buildings; vehicles; and outdoor microenvironments. The sequence of microenvironments and
exertion levels during the  exposure period is determined from characteristics of each modeled
individual.  The APEX model does this  by  generating  a profile for each simulated individual by
sampling from distributions of demographic variables such as age, gender, and  employment;
physiological variables, such as height  and weight; and situational variables, such as living in a
house with  a gas stove or air conditioning. Activity patterns from  a database  such as Consolidated
Human Activity Database (CHAD) are assigned to the simulated individual using age, gender, and
December 2009                                 3-158

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biometric characteristics. Breathing rates are calculated for each activity based on exertion level, and
the corresponding received dose is then computed. For APEX, the PM dosimetry algorithm is based
on the International Commission on Radiological Protection's Human Respiratory Tract Model for
Radiological Protection (ICRP, 1994, 006988). and calculates the rate of mass deposition of PM in
the respiratory system (U.S. EPA, 2008, 191775). Summaries of individual- and population-level
metrics are produced, such as maximum exposure or dose, number of individuals exceeding a
specified exposure/dose threshold, and number of person-days at or above certain exposure levels.
The models also consider the non-ambient contribution to total exposure. Nonambient source terms
are added to the infiltration of ambient pollutants to calculate the total concentration in the
microenvironment. Output from model runs with and without nonambient sources can be compared
to estimate the ambient contribution to total exposure and dose.
      Recent larger-scale human activity databases, such as those developed for CHAD or the
National Human Activity Pattern Survey (NHAPS), have been designed to characterize exposure
patterns among much larger population subsets than can be examined during individual panel studies
(Klepeis et al, 2001, 002437; McCurdy et al, 2000, 000782). CHAD consists of a consolidation of
human activity  data obtained during several panel studies in which diary or retrospective activity
data were obtained, while NHAPS acquired sample population time-activity  data through surveys
about human activity (Klepeis et al., 2001, 002437). The complex human activity patterns across the
population (all ages) for NHAPS are illustrated in Figure 3-93 (Klepeis et al., 2001, 002437). This
figure is presented to illustrate the diversity  of daily activities among the entire population as well as
the proportion of time spent in each  microenvironment. Different patterns would be anticipated when
breaking down  activity patterns for subgroups, such as children or the elderly. With data for average
PM concentrations in each microenvironment, population exposures can be estimated from this
break-down of time-activity  data.
  B
  O
  S*
  C3
  ^

  0}
  O
  i-i
                                   CO
                                          O  -—i (Nl  i— i  
-------
      Stochastic and deterministic methods are often combined, as described below. Recently,
SHEDS has been linked with the Modeling Environment for Total Risk Studies (MENTOR) model
to expand population exposure assessment to individual risk assessment (Georgopoulos et al., 2005,
080269). In this formulation, CMAQ was used to predict initial concentrations at a coarse scale, and
then a spatiotemporal random field method (Vyas  and Christakos, 1997, 156142) was applied to
interpolate the concentration to census tract scale in which exposure estimates are made. CHAD can
also be incorporated into MENTOR so that estimates of exposure are related to dose and metabolic
distributions to estimate risk of specific health impacts.


3.8.3.3.   Dispersion Models

      Dispersion models have been used both for direct estimation of exposure and as inputs for
stochastic modeling systems, as  described above. Location-based exposures have been predicted
using models such as CALINE, AERMOD, CALPUFF, (all described in Section 3.6.2.3)  or the
Operational Street Pollution Model (OSPM) for estimation of street-level PM pollution coupled with
infiltration models to represent indoor exposure to ambient levels (Gilliam et al., 2005, 056749;
Mensink et al., 2008, 155980: Wilson and Zawar-Reza, 2006, 088292). For instance, CALPUFF
was used to model transport and dispersion in lower Manhattan following the  September  11, 2001
World Trade Center collapse to determine average location-based exposures (Gilliam et al., 2005,
056750). Wilson and Zawar-Reza (2006, 088292) used The Air Pollution Model (TAPM), which
integrated an emissions model with amesoscale meteorological driver, to assess PMi0 dispersion and
potential for exposure in Christchurch, New Zealand. Gulliver and Briggs (2005, 191079) used the
Atmospheric Dispersion Modeling System (ADMS) to model dispersion of "line-source" traffic
emissions in an urban environment. In a method similar to that employed by Georgopoulos et al.
(Georgopoulos et  al., 2005, 080269) with SHEDS, Wu et al. (2005, 058570) used CALINE to predict
street-level concentrations of pollutants and input the results of that dispersion model into an
individual exposure model that accounts for infiltration of specific building characteristics. Wu et al.
(2005, 058570) employed CHAD to estimate the time-basis of exposures from the CALINE
predictions. With an individualized exposure approach, the model is deterministic. However,
population exposures can be estimated by performing repeated simulations using various  housing
characteristics and then computing a posterior probability distribution function for exposure. Isakov
et al. (2009, 191192) developed  a methodology to link a CTM (used to compute regional  scale
spatiotemporally-varying concentration in an urban area) with stochastic population exposure
models to predict  annual and seasonal variation in urban population exposure within urban
mi croenvironments.


3.8.3.4.   Land Use Regression and CIS-Based Models

      LUR models have also been developed to describe pollution levels as a function of source
characteristics (Briggs et al., 1997, 025950: Gilliland et al., 2005, 098820: Ryan  and LeMasters,
2007, 156063). LUR is a regression derived from monitored concentration values as a function of
data from a combination of factors (e.g., land use designation, traffic counts, home heating usage,
point source strength, and population density). The regression is then computed for multiple
locations based on the independent variables at locations without monitors. At the census tract level,
a LUR is a multivariate description of pollution as a function of traffic, land use, and topographic
variables (Briggs et al., 1997, 025950). Originally, LUR was used for NO2 dispersion, but it was
adapted for PM2.5  exposure estimation by Brauer et al. (2003, 155702) for Stockholm, Sweden,
Munich, Germany, and throughout The Netherlands. This study found a measure of traffic density to
be the most significant variable predicting PM2.5 exposure. Ryan et al. (2008, 156064) reported on a
LUR model for childhood exposure to traffic-derived EC for the Cincinnati Allergy and Air Pollution
Study and also found traffic to be the most important determinant of diesel exhaust particle exposure.
In this case, wind  direction was also factored into the model as a determinant of EC mixing. Like
deterministic dispersion models, LUR can be performed over wide areas to develop a posterior
probability  distribution function of exposure at the urban scale. However, Hoek et al. (2008, 195851)
warn of several limitations of LUR, including distinguishing real associations between pollutants and
covariates from those of correlated copollutants, limitations in spatial resolution from monitor data,
applicability of the LUR model under changing temporal conditions,  and introduction of
confounding factors when LUR  is used in epidemiologic studies.
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      A GIS platform is typically used to organize the independent variable data and map the results.
The GIS software creates numerous lattice points for the regression of concentration as a function of
the covariates. For instance, Krewski et al. (2009, 191193) computed PM2.5 concentrations for the
New York City and Los Angeles metropolitan areas. For the Los Angeles analysis, the LUR was
applied at 18,000 points in the simulation domain, and an inverse distance weighting kriging method
was applied to interpolate the predicted concentration. In New York City, the LUR was applied at 49
monitors for a 3-yr model and 36 monitors for a model of winter 2000; kriging was employed only
for the purpose of visualizing the concentration between monitors. The models explained 69% and
66% of the variation in PM2.5 in Los Angeles and New York City, respectively.
      GIS-based spatial smoothing models can be used to estimate PM concentration levels where
monitors are not located. Yanosky et al. (2008, 099467) described an approach to estimate
concentrations using a combination of reported AQS data and GIS-based and meteorological
covariates. Temporally stationary covariates included distance to nearest road for different PM size
fractions, urban land use, population density, point source emissions within 1 and 10 km buffers, and
elevation above sea level. Time-varying covariates included area source emissions, precipitation, and
wind speed. In this analysis, the GIS-based covariates were temporally stationary, while the
meteorological and PM monitored concentration inputs were time-varying. This approach was
applied to estimate PM2.5, PMi0_2.5, and PMi0 exposures for the Nurse's Health Study and provided
estimates of concentration at approximately 70,000 nodes  with PM2.5 and/or PM10 data input from
more than 900 AQS sites with good validation of the PM25 and PMi0 models (Paciorek et al., 2009,
190090; Yanosky et al., 2008, 099467; Yanosky et al., 2009, 190114).
      GIS-based methods can also be  applied to integrate exposures over different
microenvironments. For example, Gulliver and Briggs (2005, 191079) described development of the
Space-Time Exposure Modeling System (STEMS) to model PMiq concentration.  STEMS is a
multipronged model that links traffic emissions estimates, dispersion, background PM estimates, and
time-activity data within a GIS framework to create exposure estimates. Traffic emissions estimates
and meteorological parameters are input into the ADMS dispersion model, which along with
background PM measurements, are used to create hourly point estimates of PM concentration. Based
on the time-activity data, the concentration estimates were then used to calculate exposures to traffic-
related PMio along a commuting path  while an individual is in transit. PMi0 was used by Gulliver
and Briggs (2005, 191079) because ADMS had not yet been validated for smaller PM size fractions.
In an analysis of the sensitivity of included variables, Gulliver and Briggs (2005,  191079) showed
the model to be most sensitive to fluctuations in local meteorology followed by sudden vehicle speed
reductions of 10 km/h. The STEMS model was primarily designed to model exposures during
transit, but the authors state that this technique can be applied to modeling other microenvironmental
exposures.
      Source proximity is sometimes used as a covariate in GIS-based regression models. For
instance, Baxter et al. (2007, 092725)  predicted indoor exposure to PM2 5, EC, and NOX based on
distance to roadways, indoor source characteristics, window opening, and ambient concentrations in
the Boston metropolitan area. In this effort, Baxter et al. examined a variety of factors estimated
using GIS including roadway density,  roadway length, average daily traffic, and population density
to determine which variables were significant predictors. They found that point estimates of PM25
were largely influenced by regional ambient PM2 5 while EC estimates were more influenced by
local mobile sources.  However, Baxter et al. (2008, 191194) found no association between distance
to a bridge toll booth  station and indoor EC concentration in Detroit homes when studying the
impact of diesel emissions from traffic on the Ambassador Bridge as  part of the Detroit Exposure
and Aerosol Research Study (DEARS). Being located downwind of the booth, however, was a
significant predictor of indoor EC concentration. Corburn (2007, 155738) tested two distinct
modeling approaches, the cumulative  air toxics surface (CATS) and the U.S. EPA's National Air
Toxics Assessment (NATA) to determine how these approaches can yield estimates of human
exposure to diesel exhaust and  33 air toxics for environmental impact assessment. The CATS
approach included an exposure term incorporating source density and distance to  source, and the
sources include traffic as well as bus depots and transfer stations, airports, and industrial point
sources. Corburn's results demonstrated that robust land use data can provide an approximation for
urban exposures, although he cautioned that such estimates should not supersede environmental
monitoring. In using these approaches, Huang and Batterman (2000,  156572) warn that geographic
divisions must be sufficiently small to avoid inter-zone variability in  source and exposure
characteristics. Moreover, the HEI Report on Traffic Related Health Effects (2009, 191009)
December 2009                                 3-161

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discourages use of source proximity as a surrogate for traffic exposure in epidemiologic studies
because it is not specific to particular pollutants and can be subject to confounding factors such as
SES.


3.8.4.    Exposure Assessment Studies

      Table A-61 in Annex A lists exposure assessment studies performed in the U.S. by region of
the country with personal, microenvironmental, and ambient mass concentrations presented (note
that chemical speciation data, where available,  are discussed below). The majority of urban-scale
studies focus on PM2.5 because PM2.5 concentrations are more homogeneously distributed. Studies of
microscale to neighborhood scale dispersion more commonly include data on UF and thoracic coarse
PM in addition to PM2.5 because they travel over shorter distances from the site of generation, as
described in Section 3.5. Some of these studies present the outdoor concentration measured outside
the test building, while others use ambient concentration obtained from a community site monitor.
As would be expected, there is considerable variability within and across regions of the country with
respect to indoor exposures  and ambient concentrations. Furthermore, some regions are represented
by only  one or two studies, while other regions have many studies. Most studies have been
conducted in only one or two metropolitan areas. Thus, the results presented may not be broadly
representative.
      Results of these studies highlight the uncertainties surrounding various estimates of the
ambient contribution to personal exposure. This variation can be attributed to a number of factors,
including PM size distribution, scope and magnitude of microenvironmental sources, proximity to
microenvironmental sources, ambient concentrations of PM, percentages of time spent in various
microenvironments, the age and condition of indoor microenvironments, natural and urban
topography, and outdoor meteorology. Errors in exposure estimation are linked to the spatial scale of
concentration measurements because pollutant  transport and dispersion varies over different spatial
scales as a function of the many factors mentioned in the previous sentence. Findings related to
identifying the ambient components of personal exposure and modes of PM infiltration indoors are
discussed in the subsequent subsections with respect to multiple spatial scales.


3.8.4.1.   Micro-to-Neighborhood Scale Ambient PM Exposure


      Near-Road Exposures

      Sections 3.3 and 3.5 describe the physical and chemical composition of traffic emissions as
well as characterization of the plume away from roads. Table 3-24 contains data from recent studies
comparing outdoor personal exposure to fixed site monitors. Only studies where samples were
obtained outdoors and compared with a community-based ambient monitoring site were included
because indoor microenvironments have penetration losses that affect the comparability of the
results. Note that some of these studies included enclosed transportation microenvironments (e.g.,
cars, buses, subways), but all studies examined personal exposure in the outdoor microscale
environment. Also note that studies must be reviewed cautiously because most used different
instrumentation for personal, microenvironmental, and ambient measurements, and measurement
artifacts related to each instrument may differ. The Violante et al. (2006, 156140) study showed that
outdoor personal exposure to PMi0 was significantly higher than fixed community-based ambient
PMio measurements in downtown Bologna, Italy.  Likewise, the Kaur et al. (2005,  088175). Kaur
et al. (2005, 086504). and Adams et al. (2001, 019350) studies showed PM2.5 measurements to be
significantly higher than fixed community-based ambient PM2 5 monitoring site measurements in
central London, U.K. Kinney et al. (2000, 001774) performed personal exposure monitoring on
study  volunteers on streets in Manhattan and showed that PM2 5 concentrations were not significantly
different from ambient PM2 5 measurements; this is more consistent with the urban-scale
homogeneity in concentration of PM25.
      Morwaska et al. (2008, 191006) stated that UFP number concentrations in the near-road
environment were roughly  18 times higher than in a non-urban background environment, while
measured concentrations in street canyons and tunnels were 27 and 64 times higher, respectively
December 2009                                 3-162

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than background. This suggests that trapping of sources in a semi-enclosed environment can lead to
higher UFP exposures. Additionally, fresh emission of short-lived UFPs would explain substantially
higher concentrations near the site of emission. By sampling UFP number concentrations at multiple
sites in Los Angeles, Moore et al. (2009,  191004) demonstrated five- to seven-fold differences
between concentrations measured directly next to a freeway and an oceanside site during morning
rush hour with substantial variability among sites throughout the day. When comparing sampling
campaign data for clear weather and rainy days next to the 1-710 freeway in Los Angeles,
Ntziachristos et al.  (2007, 089164) found that particle number concentration obtained with a CPC
was 2.4 times higher in clear weather than when raining; particle surface area was 3.7 times larger in
clear weather; and, black carbon concentration was 1.7 times higher in clear weather. However,
SMPS data reported for rainy day particle number concentrations were almost 29 times higher in this
study. Likewise, Zhou and Levy (2007, 098633) noted in a meta-analysis of near-road studies that
the concentrations are generally elevated within 300-400 m of a roadway for EC and UFPs. Kinney
et al. (2000, 001774) showed EC to increase linearly with increasing traffic counts and large spatial
variations in two sites that had concentrations significantly higher than ambient measurements.
These observations suggest caution should be taken regarding the representativeness of community
averaged monitoring data for assessing exposures.
      Particle chemistry is also an important consideration, because exposure may differ among PM
components. Farmer et al. (2003, 089017) found that exposure to particle-bound PAHs, including
benzo[a]pyrene, can be 2-3 times higher among those routinely exposed to outdoor traffic emissions
(e.g., police, bus drivers) compared with control subjects. Particle-bound  PAH exposure can also
vary with vehicle operation.  For example, Kinsey et al. (2007, 190073) estimated from continuous
idling and restart school bus operating conditions (without retrofitting) that over a 10-min period of
waiting at a bus stop, continuous idling resulted in exposure to 33% more particle-bound PAH than
in the case where the bus was restarted 2  min into the simulation and idled for 8 min. Continuous
idling produced approximately  34 times more particle-bound PAH than in another scenario where
the bus was off for 10 min then restarted.
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Table 3-24.   Examples of studies comparing near-road personal exposures with fixed site ambient
              concentrations.
Reference
and Site
Ambient
monitors
Personal monitors m^™.
arJabTeT'' Ambientv- Personal Association
Primary Findings
Violante et al.
(2006,
1561401
          Fixed PM10 and    Active pump with PM10
          benzene monitoring PEM, passive sample for
          station (method not benzene desorbed and
Bologna, Italy  specified).       analyzed by GC-MS.
                              Localized traffic density
                              (vehicles/h);

                              Meteorology (wind
                              speed, wind direction,
                              visibility, relative
                              humidity).
                                Personal: 185.10+ 38.52 pg/m3

                                Fixed: 43.56 ± 24.10 pg/m3 (p<0.0001)
                                           Fixed PMio correlated with
                                           multivariate model of traffic and
                                           meteorology, but not personal
                                           PMi0; relationship between
                                           benzene and PM10 not
                                           explored.
Kaur et al.
(2005,
0865041

London, U.K.
Fixed TEOM for
PM2 5 and fixed CO
monitor at ambient
and curbside sites.
High flow personal
samplers for PM2 5,
P-Trak monitors for UFP,
LanganT15andT15v
for CO.
Exposures stratified by
mode of transport
(walk, cycle, bus, car,
taxi).
                                                        Average PM25 sampled by TEOM was 3
                                                        times lower than average personal PM25
                                                        sample, and 8 times lower than maximum
                                                        personal PM25 sample.
PM2 5 exposures during walking
significantly lower than during
car and taxi rides, UFP
exposures during walking
significantly lower than bus and
car rides, cycling exposures to
PM2 5 and UFP not significantly
different from those on bus,
car, or taxi.
Kaur et al.
(2005,
0881751
London, U.K.
Fixed TEOM for
PM2 5 and fixed CO
monitor at ambient
and curbside sites.
High flow personal
samplers for PM2 5
analyzed post-sample
for reflectance for EC,
P-Trak monitors for UFP,
LanganT15andT15v
for CO.
Volunteers walking at
set times and directions
along Marylebone Rd in
London.
Fixed vs. personal PM25: slope = 0.29,
R = 0.6; personal PM25 measurements
were >2 times background levels and
more than 15 pg/m greater than curbsidi
Median values: (ug/m3)
Adams et al.


London, U.K.


Kinney et al.
(2000,
0017741
New York City,
NY (Harlem)
Fixed TEOM for
PM2 5 and fixed CO
monitor at ambient
and curbside sites.


Ambient site filter in
greased impactor
with pump for
PM25; absorbance
testing on filter for
EC.

High flow personal
samplers for PM2 5.




Three high traffic sites
filter in greased impactor
with pump; absorbance
testing on filter for EC.
Exposures stratified by
mode of transport
(cycle, bus, car,
subway).




Localized traffic density
(vehicles/h).
Cycle
Bus
Car
Subway
Fixed
Curb
Mean values

Sitel
Site 2
SiteS
Ambient
Summer
345
390
37 7
247.2
15
24
: (ug/m3)
PM,,
45.7(10.1)
47.1 (16.4)
36.6(10.8)
38.7(10.9)
Winter
235
389
337
157.3
13
37

EC
6.2(1.9)
3.7 (0.6)
2.3 (0.9)
1.5(0.5)
Pedestrian exposures were
measurements. Results
a indicate that exposure declined
" up to 10% from curbside to
building edge within a street
canyon.
Exposures were 2.3-16.5 times
higher than ambient and
1.4-10.3 times higher than
curbside during summer.
During winter, only subway
exposures were appreciably
higher (4.3 times) than
curbside.
PM2 5 at high traffic sites was
not significantly higher than
ambient; EC was significantly
higher than ambient at 2 sites.
EC increased linearly with
traffic counts.
      In-Vehicle and In-Transit Exposures


      In-vehicle pollution has been identified in various studies as a source of exposure to PM2 5,
     o and UFPs (Briggs et al., 2008,  156294; Diapouli et al., 2007, 156397; Fruin et al., 2008,
097183; Gomez-Perales et al., 2004,  054418; Gomez-Perales et al., 2007, 138816; Gulliver and
Briggs, 2004, 053238; Gulliver and Briggs, 2007, 155814; Rossner et al., 2008, 156927; Sabin et
al., 2005, 087728). Results from recent studies are provided in Table A-60 of Annex A. In many of
these studies, in-vehicle exposures are shown to be comparable to or less than that of walkers on the
same route. Typically, in-vehicle exposures were also higher than community-based ambient monitor
concentrations  for TSP and PMio (Diapouli et al.,  2008, 190119). Curbside measurements of UFPs
and PM2.5 obtained at a fixed site in the Kaur et al. (2005, 088175; 2005, 086504) studies were
generally lower than exposures during transit, including during walking and cycling. In contrast, the
Adams et al.  (2001, 019350) study demonstrated that fixed site PM2.5  concentrations were higher
than curbside during the summer and lower than curbside during the winter. As  particle size
decreased to the fine and UF range, less difference between in-vehicle and ambient concentrations
was observed for PM mass or count, with the exception of the Diapouli et al. (2008, 190119) study
where in-bus UFP concentrations were several times higher than indoor or outdoor residential and
school concentrations.
December 2009
                                       3-164

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      Fruin et al. (2008, 097183) and Westerdahl et al. (2005, 086502) observed that in-vehicle UFP
concentrations increased for freeways in comparison with arterial roads. They estimated that 36% of
exposure to UFPs occurred during a total daily commuting time of 1.5 h (6% of the day) in Los
Angeles; 22% of total exposure occurred during 0.5 h spent on freeways. Gong et al. (2009, 190124)
demonstrated that UFP deposition rate increased with decreasing particle size (down to ~30 nm) and
increasing surface area inside the vehicle, where deposited PM on the seats and dashboard can be
resuspended and then inhaled or ingested. UFP deposition rate also rose slightly with increased
number of passengers. Zhu et al. (2007, 179919) found that in-vehicle UFP counts were 85% lower
than outdoors when the fan was operating in recirculation mode. They estimated that a 1-h commute
(4% of the day) accounts for 10-50% of daily exposure to UFPs generated by traffic. Based on the
American Time Use Survey estimation of an average of 70.2 min spent in vehicles per person each
day (U.S. Bureau of Labor Statistics http://www.bis.gov/tus/), cumulative in-vehicle exposure can
become important.
      In a study of PM2.5 exposure on school buses, Adar et al. (2008, 191200) found that PM2.5 on
school buses was 2 times higher than on-road levels and 4 times higher than central site
measurements. Sabin et al. (2005, 087728) demonstrated for school buses that emission control
technologies had a significant impact on in-bus concentrations of black carbon mass, and Hammond
et al. (2007,  190135) demonstrated significant reductions of particle number concentration measured
for 0.02-1 um particles when comparing buses using clean diesel or retrofits compared with non-
retrofitted buses. Although not tested here for other vehicle types with respect to PM, these findings
suggest that a portion of in-vehicle concentrations are due to self-pollution, defined by Behrentz et
al. (2004, 155682) as the fraction of a vehicle's own exhaust entering the vehicle microenvironment.
Behrentz et al. (2004, 155682) tested self-pollution with school buses using SF6 tracer gas  and
demonstrated that 0.3% of in-vehicle air comes from self-pollution, and that this number was
roughly 10 times greater than in-vehicle concentrations related to self-pollution on newer buses. The
Behrentz et al. (2004, 155682) study also measured EC and particle-bound PAH and found that 25%
of the variability in EC concentration was related to self-pollution. Adar et al. (2008, 191200)
estimated that 35.5% of PM25 mass on school buses was from self-pollution.  These findings are
important for exposure estimation when partitioning local and ambient sources of pollution during
transport in vehicles.


3.8.4.2.  Ambient PM Exposure Estimates from Central Site Monitoring  Data

      The following paragraphs describe studies that estimate personal exposure to ambient PM
from central site monitoring data. As shown in Figure 3-93, the large majority of an individual's time
is spent indoors. Although calculation of infiltration and indoor personal exposure  is an important
part of this assessment,  such exposures are described with respect to central site monitors. Assessing
population-level exposure at the urban scale is particularly relevant for epidemiologic studies, which
typically provide information on the relationship between health effects and community-averaged,
rather than individual, exposure.
      Indoor or other nonambient sources could significantly affect assessment of a person's total
exposure to many pollutants. For this reason, many studies use PM components to estimate
infiltration of ambient PM to indoor environments. Wilson et al. (2000, 010288) first proposed that
SO42~ could be used as a tracer of the ambient PM25 infiltration rate. Sarnat et al. (2002, 037056)
also noted that it is reasonable to assume  that the size distribution of ambient SO4 ~ particles is
sufficiently similar to the size distribution of ambient PM2 5, and therefore that the  ambient SO42~ to
personal SO42~ ratio is an acceptable surrogate for the ratio of the ambient PM25 exposure to the
ambient PM25 concentration. Sulfate has  been used this way in several studies, including Ebelt et al.
(2005, 056907). Wallace and Williams (2005, 057485; 2006, 089190) and Wilson and Brauer (2006,
088933). For this method to be successful, indoor  or other nonambient sources of the tracer must be
small compared to ambient sources over the period of sampling. Wilson and Brauer (2006, 088933)
noted that environmental tobacco smoke and tap water used in showers or humidifiers are indoor
sources of SO42~. Other concerns in using SO42~ as a tracer for PM2 5 arise because  SO42~ tends  to be
concentrated in the accumulation mode and thus it might not capture any coarse PM found in the
upper end of the PM2 5 distribution, which can include larger particles in the tail end of the coarse
mode (Wallace  and Williams, 2005, 057485). Strand et al. (2007, 157018)  suggested that Fe be used
as an additional tracer to correct for the infiltration of larger PM25 particles. Their study took place in
Denver, where indoor sources of Fe were small. However, there could be more substantial
December 2009                                 3-165

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contributions from tracking iron in soil indoors in other locations. The spatial variability of Fe is also
larger than that of PM2.5 across urban areas. Volatilization of nitrate or organic compounds after
infiltration of PM2.5 indoors could lead to bias in exposure estimates (Sarnat et al., 2006, 089166).
This could be a large problem in areas in which PM contains a large semi-volatile component.
      Figure 3-94 shows total exposure to SO42~ as a function of measured ambient SO42~
concentration. Figure 3-95 shows estimated ambient exposure to PM2.5 as a function of measured
ambient PM2.5 concentration, where ambient personal exposure is calculated from the ambient
exposure factor for SO42~. Close agreement between these figures can be observed. Figure 3-96
shows total exposure to PM25 as a function of measured ambient PM25 concentration. However, the
total exposure to PM2 5 shows virtually no association with ambient PM2 5 because it contains
nonambient contributions to PM25.
                        LU
                                         *
                                         2345
                                Ambient Concentration, C50
-------
                                                           8-24
Figure 3-96.
                 0    5    '0    15    20    25    30
                    Ambient Concentration, C2 5 (pg/rn3)

                        Source: Reprinted with Permission of Nature Publishing Group from Wilson and Brauer (2006, 0889331

Total exposure to PM2.6 as a function of measured ambient PM2.6 concentration,
from the Vancouver study.  Vancouver, British Columbia, April-September 1998,
with 16 non-smoking subjects aged 54-86 yr.
      The estimated ambient exposure to PM2.5 is well correlated with measured ambient PM2.5
concentration with zero intercept, implying that nonambient sources were minor. This technique
works well in areas where SO4 " is a regional pollutant, because its spatial variability is small(Kim et
al., 2005, 083181; U.S. EPA, 2004, 056905). Wilson and Brauer (2006, 088933) reported that the
pooled Pearson correlation coefficient was 0.79 for personal ambient exposures (estimated by the
tracer element method) vs.  ambient concentrations of PM2.5, and it was 0.001 for personal
nonambient PM2.5 exposure vs. ambient concentrations. Strand et al. (2006, 089203) conducted an
exposure study in Denver (2002-2004) for 6-12 year-old school children. Up to 10 personal exposure
samples were collected on each day, and ambient concentrations were measured simultaneously at a
fixed site located at the school. The daily average personal SO42" exposure was strongly associated
with ambient SO42" concentration (r = 0.96, 120 > N > 100). Koutrakis et al. (2005, 095800) reported
the median Spearman correlation coefficients between personal SO42" exposure and ambient SO42"
concentration were above 0.60 during both winter and summer in Boston and Baltimore (15 subjects
with 12 consecutive measurements during each season in both Boston and Baltimore). For another
Baltimore cohort (15 senior subjects with up to 23 consecutive measurements for each person),
Hopke et al.  (2003, 095544) reported that the median Pearson correlation coefficient between
personal exposure to the SO42" factor and the ambient SO42" factor was 0.93 (ranging from 0.56 to
0.98 for different subjects), while the median Pearson correlation coefficients were 0.25 for the
crustal factor (ranging from -0.46 to 0.66) and 0.22 for a factor whose  origin was  not identified
(ranging from -0.19 to 0.88). The inferences  drawn from using the SO42~ component of PM25 as an
indicator for personal exposure to ambient PM2 5  may apply in areas where SO42~ is a minor
component of PM25 or in the absence of significant nonambient sources of SO42~  (Sarnat et al., 2001,
019401).
      Source apportionment techniques could also be used, in principle, to derive ambient personal
PM25 exposures. They would be especially useful in areas where the application of a tracer method
might be problematic.  Hopke et al. (2003, 095544) noted that four outdoor factors (NH4NO3~ and
(NH4)2SO4, secondary SO42", OC, motor vehicle exhaust) would constitute an estimate of the
personal ambient PM25 concentration. However, the data used in this portion of the analysis were
obtained only with fixed monitors and did not include measurements made by PEMs. They also used
the Multilinear Engine to derive factors that were required to contribute jointly to central indoor and
outdoor, individual apartment, and PEM samples  of a panel of residents. Hopke et al. (2003, 095544)
used PMF to derive source contributions to community, outdoor, and indoor PM exposures  at a
retirement facility in Towson, MD. Hopke et al. (2003, 095544) found three sources: SO42~,
unknown (perhaps combustion related, according to the authors), and soil, jointly contributing 46%,
13%, and 4% of PM25 to the PEM samples, respectively. Further source resolution was not possible
because there was a lack of data for a number of components in the PEM samples. The largest and
most clearly identified contribution to personal exposure was from the SO42" factor. This study also
December 2009
                              3-167

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determined that a few minor indoor and personal activity sources contributed <10% of the ambient
SO42" source to personal exposures.
     Wilson and Brauer (2006, 088933) presented an adaptation of the SO42~ method for estimating
exposure to PMi0_2.5. a is computed based on the SO42~ method as the ratio of exposure to ambient
SO42 (as measured by a personal monitor) to ambient SO42~ concentration. Then, knowing an
individual subjects' time diary and the penetration and loss properties of SO42~, the air exchange rate
for an individual location can be calculated from Equation 3-5 and Equation 3-7. Finally, the
penetration and loss rates of PMi0_2.5 from the PTEAM database  (Ozkaynak et al.,  1996, 073986) can
be input into the individual exposure model along with the individual activity pattern and residential
air exchange rate to compute the ambient PMi0_2.5 exposure factor and the ambient PMi0_2.5 exposure
if PM 10-2.5 concentration is measured; in the Wilson and Brauer (2006, 088933) paper, PMi0_2.5 was
estimated from ambient PMi0 and PM2 5 concentrations. Given that PMio-2.5 deposits more readily
and therefore disperses over a shorter distance than PM2.5, it is possible that use of ambient PM10_2.5
concentration may incur more error than in using this method for PM2 5. Ebelt et al. (2005, 056907)
observed in a Vancouver, Canada panel study that the correlation between ambient PMi0_2.5 exposure
and ambient PMi0 exposure (r = 0.72) was lower than the correlation between ambient PM25
exposure and ambient PMi0 exposure (r = 0.92). This is attributed to both a smaller Finf for PMi0_2.5
and PM25 comprising a greater fraction of the PMi0 for the Vancouver study. In this study, PMio_2.s
mass concentration was calculated from the difference between ambient PM10 and PM2 5 mass
concentration.
     Wilson and Brauer (2006, 088933) state that their methodology for computing the ambient
exposure factor based on the PM25 SO4 ~ method can be applied to PM in the 0.1-0.5 (im size range.
Little SO42~ mass is found below 0.1 (im, so the SO42~ tracer method would not be applicable for
UFPs. Given the short atmospheric lifetime of UFPs resulting  from particle growth and  evaporation
processes, primary UFPs are most prevalent at microscale rather than at an urban spatial scale
(Sioutas et al., 2005, 088428). Moore et al. (2009, 191004) found substantial spatial, hourly, and
daily variability in UFP concentration in a saturation study of Los Angeles. Moore et al. (2009,
191004) and Harrison and Jones (2005, 191005) also found that  UFPs and PM2 5 measurements were
poorly correlated at the monitoring sites.


3.8.4.3.   Infiltration

     Finf varies substantially given a vast array of conditions, and it can best be modeled
dynamically based on a distribution of air exchange and deposition or other UF, accumulation mode,
fine, and coarse PM loss rates rather than a single value (Bennett and Koutrakis, 2006, 089184;
Wallace et al., 2006, 089190). Given that air exchange rates within a building vary as a function of
ambient temperature and pressure, Fjnf is subject to seasonal and regional changes  (Meng et al.,
2005, 058595; Sarnat et al.,  2006, 089166; Wallace and Williams,  2005, 057485). These factors
make Finf a more accurate descriptor of infiltration than a simple I/O ratio because the I/O ratio also
includes contributions from indoor sources in addition to PM that infiltrates from outdoors. Wallace
et al. (2006, 089190)  identified several significant factors affecting Fjnf, including  window opening,
age of an indoor microenvironment, number of occupants, location on a dirt road,  dryer usage, and
air conditioning usage. This term becomes even more complex when one considers transformation of
the size distribution and chemical composition of the PM through chemical reactions on the particle
surface, agglomeration, growth, and evaporation given that Finf depends on particle size (Keller and
Siegmann, 2001, 025881). Finf for PM is influenced by physical mechanisms, such as Brownian
diffusion, thermophoresis, and impaction, all  of which are functions of particle size (Bennett and
Koutrakis, 2006, 089184: Tung et al.,  1999, 049003). These differential effects are summarized
below. Recent studies on infiltration are summarized in Table A-64 of Annex A. Fjnf and I/O are
listed where available, although it is recognized that I/O is not as meaningful a descriptor but
provides an approximation of Finf.
     A number of studies have examined the impact of season on PM infiltration. Season is
important because it affects  the ventilation practices used (e.g., open windows, air conditioning or
heating use) and ambient temperature and humidity conditions influence the transport, dispersion,
and size distribution of the PM. Pandian et al. (1998,  090552)  found that nationwide residential air
exchange rates vary by season as: summer > spring > winter > fall  with summer air exchange
roughly  1.5-2 times greater than average air exchange rate for  the entire year because the rates are
driven by home air conditioning and heating usage. Allen (2003, 053578) provided information on
December 2009                                 3-168

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the range and distribution of Finf for PM2.5 at 44 residences in Seattle. The mean F^ was calculated
using light scattering measurements in a recursive mass balance method with no species data.  For
all sampling days, F^f (± SD) was 0.65 ± 0.21. Differences in infiltration were observed for the
heating season (0.53 ± 0.16), when windows would be expected to be closed, and for the non-heating
season (0.79 ± 0.18). Residences with  open windows had a meanFinf of 0.69 vs. 0.58 for residences
with closed windows. The authors combined the light scattering results with indoor and outdoor
sulfur measurements to estimate that 79 ± 17% of indoor PM25 was generated outdoors. This study
provides important data on the distribution of residential Fjnf values and illustrates the magnitude of
the effect of season and window position on infiltration rates. Barn et al.  (2008, 156252) and Baxter
et al. (2007, 092725) also noted that window opening was an important variable. Barn et al. (2008,
156252) foundFjnf of 0.61 ± 0.27 for 13 homes during summer and 0.27  ± 0.18 for 19 homes during
winter in Canada for PM2.5 from forest fires and wood smoke.
      Likewise, location could impact residential ventilation practices and infiltration. Using the
SO42" method for estimating PM2.5 infiltration, Cohen et al. (2009, 190639) noted differences in
median infiltration among eight areas (including three comprising the Los Angeles region and two
comprising the New York City region). Indoor-outdoor SO42~ ratio was noted to be highest in New
York City (median: 0.85) and Los Angeles (median: 0.84) and lowest in St. Paul (median: 0.54).
Pandian et al. (1998, 090552) observed that residential air exchange rates vary by region as:
southwest > southeast > northeast > northwest, which reflects regional use of air conditioning.  Sarnat
et al. (2006, 089166) noted differences in PM2 5 infiltration between coastal and inland residences,
although these differences were not statistically significant.
      Differential Infiltration Related to PM Size

      Differential infiltration as a function of particle size has been observed to occur. Infiltration
factors for particle diameters ranging from 20 nm to 10 um were measured using continuous SMPS-
APS monitoring in Boston by Long et al. (2001, 011526) during summer and fall for nighttime
periods, when personal activity patterns would be less likely to generate indoor PM. The maximum
infiltration factor was reported for particles between 80 and 500 nm to range from 0.8 to 1.0.
Summer values were uniformly higher than fall values, consistent with higher observed air exchange
rates. The infiltration factor decreased with size above 500 nm, reaching 0.1-0.2 for 6-10 um
particles. Particles smaller than 80 nm also were reported to have lower infiltration factors. This
demonstrates the size dependence of PM infiltration, which has been further studied by recent
investigators. Sarnat et al. (2006, 089166) examined infiltration as a function of particle size and
found that I/O varies by particle diameter, as measured by a SMPS-APS system. Figure 3-97
presents I/O values for size fractions ranging from 0.02 to 10 urn. The maximum infiltration was
observed around the accumulation mode (0.1-0.5 um), with I/O = 0.7-0.8. Reduced infiltration was
observed for coarse-mode PM (0.1-0.2 for Dp = 5-10 urn) and, to a lesser extent, UFPs (0.5-0.7 for
Dp = 0.02-0.1 um). This is consistent with increased removal mechanisms for those size fractions.
Deposition is caused by settling for coarse-mode particles. Deposition of UFP can occur by diffusion
leading to agglomeration into larger particles and subsequent settling, as well as losses to walls.
December 2009                                 3-169

-------
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                                   Source: Reprinted with Permission of Air & Waste Management Association from Sarnat et al. (2006, 0891661.

Figure 3-97.   Finf as a function of particle size.



3.8.5.    Multicomponent and Multipollutant PM Exposures



3.8.5.1.   Exposure Issues Related to PM Composition

      Annex A presents exposure studies that include chemical speciation data in Table A-62. Some
of these studies focused on SO42~, NO3~, or carbonaceous aerosols (EC, OC, particle-bound PAHs),
while others measured concentrations of trace elements from crustal (Ca, Fe, Mn, K, Al, S, Cl in
salt), mobile (Al, Ca, Fe, K, Mg, Na, Ba, Cr, Cu, Mn, Ni, Pb, S, Ti, V, and Zn), or industrial
(particle-bound Hg, Cl, V, Zn, Ti, Cu, Pb) sources. A number of source apportionment studies have
been performed over the last five years to determine the contribution of outdoor sources to indoor
and personal PM constituents.
      Source apportionment studies by Kim et al. (2005, 083181). Hopke et al. (2003, 095544) and
Zhao et al. (2006, 156181) have shown that secondary SO4Z~ provides the largest ambient
contribution to personal and indoor exposures. These studies took place in Baltimore, MD and
Raleigh/Chapel Hill, NC. In a source apportionment study in Seattle, vegetative burning was the
most significant source of outdoor origin (Larson et al., 2004, 098145). Zhao et al. (2007,  156182)
performed a source apportionment study of personal exposure to PM2.s among residents in Denver
and also observed lower contributions  from secondary SO42~ in comparison with motor vehicle
emissions and secondary NO3~.  This suggests that personal exposure to SO42~ in parts of the West is
lower than in the Mid-Atlantic.  These observations are consistent with the composition distribution
shown in Figure 3-17 and Figure 3-18. Viana et al. (2008, 156135) selected 4  sites of varying
population density to represent exposures of pregnant subjects in an early childhood epidemiologic
study.  Viana et al. (2008, 156135) analyzed PM2.5 and PMi0 samples for  several species along
urban-to-rural gradients centered in Valencia, Spain and found gradients for both size fractions in
anthropogenically-generated SO42~, OC, EC, NO3", Fe, and NH4+, but not in mineral species.
December 2009
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Combined, these findings suggest urban- and regional-scale variation in species composition can
influence exposure estimates. Personal PM exposure studies including source apportionment analysis
along with chemical speciation are presented in Annex A, Table A-63.
      Source apportionment for carbonaceous aerosols is complicated by the fact that they can be
derived from indoor and outdoor combustion sources. Carbonaceous aerosols are difficult to trace to
specific indoor and outdoor sources because combustion is widespread. Sorensen et al. (2005,
089428). Ho et al. (2004, 056804). Larson et al. (2004, 098145). and Jansen et al. (2005, 082236) all
found that personal and microenvironmental exposure to total carbon or BC was lower than that
measured outdoors, while Sarnat et al. (2006, 089166)  showed significant associations between
personal and ambient measurements of EC for measurements taken during the fall for low and high
ventilation conditions (slope = 0.66-0.73) and during the summer for high ventilation conditions
(slope = 0.41). Wu et al. (2006, 179950). Delfmo et al.  (2006, 090745). Olson and Norris (2005,
156005) and Turpin et al. (2007, 157062) all demonstrated much higher levels of OC compared with
EC in personal samples, possibly due to  indoor sources of OC from cooking and home heating. Reff
et al. (2007,  156045) and Meng et al. (2007, 194618) both reported findings from the Relationships
between Indoor, Outdoor, and Personal Air (RIOPA) study  in Los Angeles, Houston, and Elizabeth,
NJ. Results from Reff et al. (2007, 156045) reveal significantly higher detection of aliphatic C-H
functional groups indoors and in personal samples compared with outdoors (Figure 3-98). This
information may help to distinguish carbonaceous compounds  of indoor and outdoor origin in future
source apportionment studies of PM exposure. Little regional variation in the aliphatic, carbonyl, or
SO42~ groups tested were reported in this study. In Meng et al. (2007, 194618). indoor exposures
were shown to decrease for secondary formation aerosols including SO4 ~ but not NO3~ (not tested)
when compared with outdoor concentrations. In this study, indoor exposures to mechanically
generated aerosols decreased in comparison with outdoors (Figure 3-99).
      Trace metal studies have shown variable results regarding personal exposure to ambient
constituents. For instance, Molnar et al.  (2006,  156773) found that personal exposure was higher
than outdoor and ambient concentrations for mostly crustal Cl, K, Ca, Ti, Fe, and Cu. However,
Adgate et al. (2007, 156196) found that  personal exposures were higher than ambient for Fe, Mg, K,
Zn, Cu, Pb, and Mn but lower than ambient for Al, Na, and Ti.  Larson et al. (2004, 098145) found
that personal  exposure to Ca and Cl were higher than concentrations measured at ambient (central
site) and residential outdoor monitors, lower for Fe, K, Mn, and As and the same for Al, Br, Cr, and
Cu. Source apportionment for trace metals can vary significantly among cities and over seasons. For
instance,  in a Baltimore source apportionment study, exposure  to Mn could be attributed nearly
equally to the Quebec wildfires, roadway wear, and soil, while Pb exposure was largely found to  be
due to a local incinerator (Ogulei et al., 2006, 119973). In this case, the Quebec wildfires  were a
transient episodic source, while roadway wear and incineration were continuous. However,  in Larson
et al. (2004, 098145). Mn and Pb exposures in Seattle were largely attributable to mobile  source and
stationary source emissions. For this reason, source composition behavior cannot be generalized for
characterizing exposures and resulting health effects across multiple locations or times.
December 2009                                 3-171

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Figure 3-98.   Apportionment of aliphatic carbon, carbonyl, and S042" components of outdoor,
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              Houston (bottom).
December 2009
3-172

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Figure 3-99.   Apportionment of infiltrated PM from mechanical generation (top), primary
              combustion (center), and secondary combustion (bottom).
December 2009
3-173

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      Differential Infiltration Related to PM Composition

      A number of chemical factors influence the tendency for differential infiltration in PM.
Lunden et al. (2003, 156718) studied infiltration of BC and OC aerosols and found that F^f can vary
substantially as a function of gas transport properties with differing air exchange rates. This study
and Sarnat et al. (2006, 089166) also showed that BC aerosol infiltration is considerably higher than
infiltration of OC,  and that carbonaceous aerosol infiltration differed substantially from NO3~ and
SO42~ aerosols under the same building air exchange conditions. These disparities are likely related
to differences in the particle size distribution of PM components, as described in Section 3.8.4.3. As
shown in Figure 3-100, the composition of indoor PM that has infiltrated from outdoors is different
from that of outdoor PM (Meng et al., 2007, 194618).  In this case, the particles containing
photochemical products (primarily accumulation mode) have a higher infiltration rate than the larger
(primarily coarse mode) mechanically generated particles or the smaller primary combustion
particles (likely to  consist mostly of UFPs  in the nucleation or Aitken nuclei mode).
                     7-
                     5-
                                             Photochemical
                                              Secondary
                                           •Accumulation Mode)
                                           Primary
                                         Combustion
                                           Particles
                                          ~ Ultrafine)
  Mechically
  Generated
(~ Coarse Mode)
                          Out     In
                     Out     In           Out      In

                             Source: Reprinted with Permission of ACS from Meng et al. (2007,1946181.
Figure 3-100.   Results of the positive matrix factorization model showing differences in the
               mass of outdoor PM and PM that has infiltrated indoors based on source
               category.

      PM species enriched in the accumulation mode, such as SO42~, will infiltrate more efficiently
than components with larger size distributions, such as iron (Strand et al., 2007, 157018). Lunden et
al. (2008, 155949) also compared I/O ratios for PM25, total carbon, OC, and BC in an unoccupied
house and found the lowest ratio for PM2.5 (0.41 ± 0.2), the highest for BC (0.61 ± 0.2), and
intermediate values for total carbon (0.50 ± 0.2) and OC (0.47 ± 0.2). The authors attributed the
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lower PM2.5 I/O ratio to indoor loss of NH4NO3 aerosol. The authors note that their BC I/O of 0.6 is
somewhat lower than BC ratios measured in occupied spaces (Polidori et al., 2007, 156877).
Conversely, indoor sources in occupied residences contribute to observed OC I/O ratios greater than
1 in other studies (Polidori et al., 2006, 156876; Sawant et al., 2004, 056798). Analytical results for
PM2.5 components from the Baxter et al. (2007, 092726) study found Fmf of 0.95 ± 0.07 for S and
0.60 ± 0.04 for V, the two components identified as having no indoor sources and which had I/O
ratios significantly less than 1 (Baxter et al., 2007, 092726). It is possible that association of V with
larger particles of lower penetration efficiency could contribute to a lower infiltration rate. Meng et
al. (2005, 058595) also noted that the lack of indoor sources of S and V result in much lower
variability in penetration and loss rates.
      Volatilization of PM during infiltration can cause differences between the composition of
indoor and outdoor PM. NO3~, a prevalent PM component year-round in the western U.S. and during
winter throughout the mid-western and northeastern states, has a decreased Finf due to volatilization
of NO3~ indoors. Sarnat et al. (2006, 089166) calculated Fmf values forNO3~, PM2.5, and BC, and
found the values to increase in that order. NO3~ was low (median = 0.18, IQR = 0.12-0.33), while BC
was high (median = 0.84, IQR = 0.70-0.96); the intermediate value of PM2.5 (median = 0.48,
IQR = 0.39-0.57) reflected its composition as a mixture of those two components (among others).
Indoor volatilization of NO3~ enriches indoor ambient PM in other components, creating differences
in toxicity between indoor and outdoor ambient PM. The high infiltration of non-volatile BC creates
additional sorption sites for organics, including indoor-generated compounds. Meng et al. (2007,
194618) found that secondary formation accounts for 55% of indoor PM of outdoor origin, while
primary combustion accounts for 43%, and mechanical generation accounts for 2%. Meng et al.
(2007, 194618) noted that secondary formation processes  often result in more accumulation mode
particles, so that diffusion losses are not as great as for primary combustion particles that are
composed primarily of nucleation and condensation size modes (Figure 3-100). Likewise, Polidori et
al. (2007, 156877) suggest that similarities in the EC and OC size distributions and infiltration
factors reflect low vapor pressure secondary organic aerosols in the  OC component. Sioutas et al.
(2005, 088428) suggest that volatilization of UFPs while crossing the building envelope may impede
infiltration in this size range. Variations in the presence of outdoor PM indoors, and resulting
changes in removal behavior once indoors, relate to the species composition of PM.


3.8.5.2.   Exposure to PM and Copollutants

      Analysis of personal exposure to multipollutant mixtures is an area of growing research.
Several multipollutant studies involving UF, fine, and coarse PM are presented in Table A-65. Sarnat
et al. (2001, 019401) found significant associations between personal exposure to PM25 and ambient
concentrations of O3, NO2, CO (significant only for winter), and SO2 in a panel study conducted in
Baltimore. Personal exposures to PM2 5 and personal exposures to the gases were not correlated in
this study. This result may have arisen in part because personal exposures to the gases were often
beneath detection limits of the personal monitoring devices. Schwartz et al.  (2007, 090220) also used
data from the Baltimore panel study to simulate distributions of personal exposures and ambient
concentrations of PM25, PM10, SO42~, NO2, and O3. They found that personal exposure to ambient
PM2 5 was significantly associated with ambient concentrations of PM2 5, NO2s and O3 (O3 in an
inverse relationship). They also reported that personal exposure to SO42~ was significantly positively
associated with ambient PM2 5 and O3 concentrations.
      There is evidence that associations between ambient gases and personal exposure to PM2 5 of
ambient origin exist but are complex and vary by season and region. Seasonality of the associations
could be a result of seasonal variability in photochemistry, source generation, and building
ventilation. Sarnat et  al. (2005, 087531) observed associations between personal exposure to total
PM2 5 and ambient concentrations of O3, NO2, and SO2 measured at  community-based monitors for
groups of healthy senior citizens and school children in Boston during the summer. In this study,
significant associations between personal exposure to ambient PM2 5 and personal O3 exposures were
observed in summer and between personal PM2 5 and personal NO2 in winter and summer, unlike the
Baltimore study in which only summertime personal PM2 5 and personal NO2 were associated
(Sarnat et al., 2001, 019401). In their study of personal exposure to ambient air pollutants in
Steubenville, OH, Sarnat et al. (2006, 090489) found low  but significant associations for ambient O3
with personal PM2 5, SO42~, and EC in the summer. Low but significant associations between ambient
SO2 and personal PM2 5, and between ambient NO2 and personal EC, were also observed. In the fall,
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ambient O3 had a weak but significant association with personal EC, and SO2 had a weak but
significant association with personal SO42~. Ambient NO2 was also significantly associated with
personal PM25, SO42~, and EC with somewhat higher coefficient of determination (R2 = 0.25-0.49) in
the fall.


3.8.6.   Implications of Exposure Assessment Issues for Interpretation of
         Epidemiologic Studies

      Environmental epidemiologic study designs vary by many factors, including study sample
size, measurement time interval, study duration, monitor type, and spatial distribution of the study
sample. A panel epidemiology study consists of a relatively small sample (typically tens) of study
participants followed over a period of days to months. Time-activity diary studies are examples of
panel studies (e.g., Cohen et al, 2009, 190639: Elgethun et al, 2003, 190640; Johnson et al., 2000,
001660; Olson and Burke, 2006, 189951). and a microenvironmental model might be applied to
represent exposure in this case. Community time-series studies may involve millions of people
whose exposure and health status is estimated over the course of a few years using a short
monitoring interval (hours to days). Because so many people are involved, community-averaged
concentration is typically used as a surrogate for exposure in community time-series studies.
Exposures and health effects are spatially aggregated over the time intervals of interest because they
are designed to examine health effects and their potential causes at the community level (e.g.,
Dominici et al., 2000, 005828; Peng et al., 2005, 087463). A longitudinal cohort epidemiology study
typically involves hundreds or thousands of subjects followed over several years or decades.
Concentrations are generally aggregated over time and by community to estimate exposures  (e.g.,
Dockery et al., 1993, 044457; Krewski et al., 2000, 012281). The importance of exposure
misclassification varies with study design based on the spatial and temporal aspects of the design.
Other factors that could influence exposure estimates in PM epidemiologic studies include source
characteristics, particle size distribution, and particle composition. Potential issues that could
influence estimates of PM exposure include measurement, modeling, spatial variability, temporal
variability, use of surrogates for PM exposure, and compositional differences. These are described in
detail in the following sections.


3.8.6.1.   Measurement Error
      Measurement Error at Community-Based Ambient Monitors and Exposure
      Assessment

      Community-based ambient monitors are employed for time-series and longitudinal studies,
although they can be used for panel studies as well. Section 3.4 discusses potential errors in
measuring ambient PM in detail. Because there will likely be some random component to
instrumental measurement error, the correlation of the measured PM mass with the true PM mass is
expected to be <1. Sheppard et al. (2005, 079176) indicate that instrument error in the hourly or
daily average concentrations has "the effect of attenuating the estimate of a."  Zeger et al. (2000,
001949) suggest that in order for this error to cause substantial bias in later estimation of a health
outcome, the measurement error must be strongly correlated with the measured concentrations.
Positive and negative artifacts resulting from sampling volatile PM may therefore lead to lack of
association with health endpoints in time-series and longitudinal studies. In multicity longitudinal
studies, where PM composition and associated artifacts may vary across cities, the cumulative
influence of such artifacts on exposure estimates is more difficult to predict.


      Measurement Error for Personal Exposure Monitors

      PEMs are primarily used in panel exposure studies to measure total exposure to PM (e.g.,
Cohen et al., 2009,  190639; Elgethun et al., 2003, 190640; Johnson et al., 2000, 001660;  Olson  and
Burke, 2006, 189951). PEMs are specialized monitors that, because people must carry them, have to
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be small, light, quiet, and battery operated or passive. As a result, they may have lower face
velocities across the filter and lower pressure drops than ambient-based filter measurements  of PM,
which typically sample at much higher flow rates, and consequently at much higher face velocities.
Light scattering measurements are biased when relative humidity is high and are sensitive to size
distribution (Lowenthal et al., 1995, 045134; Sioutas et al, 2000, 025223). Positive artifacts
resulting from adsorption of vapor-phase organic compounds and negative artifacts from evaporation
of semi-volatile PM also create challenges for interpreting personal exposure monitoring data (e.g.,
Pang et al., 2002, 030353). Olson and Norris (2005, 156005) attributed more OC particle mass
collection to face velocity differences when using PEMS compared with FRMs. Data quality of
PEMs is described in much greater detail in the 2004 PM AQCD (U.S. EPA, 2004, 056905). The
artifacts listed here could result in either negative or positive sampling bias.


3.8.6.2.   Model-Related Errors

     When models are used in lieu of or to supplement measurements of ambient PM exposure or
community-based ambient PM concentration, it is important to identify errors and uncertainties that
could affect estimates of PM-related health effects. Model-related errors are determined by four
factors: representativeness of the mathematical model,  accuracy of model inputs, scale of model
resolution, and model sensitivity. If verification errors related to these four factors are minimized,
then the model can be evaluated against physical data to determine how well the model truly
captures a real situation (Roache, 1998, 156915). Detail of the model design and inputs can have
significant impact on validation, as observed in Meng et al.(2005, 058595) and Hering (2007,
155839). Meng et al. (2005, 058595) demonstrated how use  of an increasingly more detailed
mathematical model decreases the variability of the results with respect to modeled indoor PM2.5
concentration of outdoor origin and to modeled infiltration factor. Hering (2007, 155839) compared
infiltration model results for PM-based EC, NO3~, and SO42~. Model inputs were from a central site
monitor only, central site monitor with air exchange data, and detailed inputs related to initial
outdoor (outside test building) and indoor concentrations. Use of more detailed inputs resulted in
significant reductions in error for indoor EC concentration, smaller improvements for indoor SO42~,
and negligible improvement in model results for indoor NO3~. This illustrates the impact of
differential infiltration discussed in Sections 3.8.4 and 3.8.5.
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                                                                36 km CMAQ grid
                                                                12km CMAQ grid
                                                                 4 km CMAQ grid
                                                               Census tract
                                                               centroids
                                                               in Philadelphia
                                                               county:
                                                               Tracts in each
                                                               4x4km
                                                               grid cells are shown
                                                               in different colors
           4405
             465   470
                      475
                           480   485  490   495   500
                               West-East distance (km)
                                                  505   510
                                                            515
                                                    Source: Reprinted with Permission of ACS from Isakov et al.(2007,195880).

Figure 3-101.  Grid resolution of the CMAQ model in Philadelphia compared with distribution of
              census tracts in which exposure assessment is performed.

      For any spatial interpolation models, grid resolution is another source of error. Isakov et al.
(2007, 195880) linked CMAQ with the Hazardous Air Pollutant Exposure Model for exposure
assessment in Philadelphia. Their simulation was implemented on a 4 km nested grid within 12 km
and 36 km grids to bring the scale of their model from national to urban. However, the census tracts
in which Isakov et al. (2007,  195880) sought to describe exposure were distributed on a much finer
scale (Figure 3-101). They supplemented the CMAQ model with an Industrial Source Complex
Short Term (ISCST) dispersion model to resolve the subgrid scale behavior. If concentrations were
averaged across the cell in lieu of a more detailed subgrid representation, Isakov et al. (2007,
195880) found that exposures were overestimated by a factor of 2. Appel et al. (2008, 155660) noted
that their 36 km simulations provided a closer estimate of SO42~ aerosol concentration than did their
12 km nested simulation, which overestimated concentrations. Hogrefe et al. (2007,  156561) also
noted overestimation of the CMAQ model at the 12 km scale, where multiple point interpolation was
used to obtain subgrid estimates. Model convergence theory would suggest that the 36 km simulation
is not actually more accurate but coincidentally closer  to the observed concentrations (Roache, 1998,
156915). It is possible that if secondary pollutants are more regionally dispersed, lower spatial
resolution would be required to attain a converged solution of the spatial concentration field.
However, higher spatial resolution in the simulation should produce very similar results if the
solution is convergent.
      Use of geospatial statistical methods for grid interpolation, as performed in the
SHEDS/MENTOR simulation by Georgopoulos et al. (2005, 080269). provides another
methodology for grid interpolation. Similar to Isakov et al.(2007,  195880). Georgopoulos et al.
(2005, 080269) linked CMAQ with an exposure model for estimation of neighborhood-scale
exposures using a 4 km resolution grid nested within 12 km and 36 km grids. The authors found that
CMAQ underestimated PM2.5 concentration at many times during the simulation. Kim et al. (2009,
188446) compared results from an exposure model using six different levels of spatial resolution.
The model predicted PM2.5 at monitor locations as a function of the  mean concentration and spatial
and random errors. The 6 levels of spatial resolution were simulated through assignment of the
spatial and random error terms and by defining the distance over which spatial errors are correlated.
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Between monitors, Kim et al. (2009, 188446) compared results from assigning nearest monitor
values and from kriging. They found that model prediction error and bias in health effects estimates
decreased with increased spatial resolution of the error terms, as well as with kriging over a nearest
monitor scheme.
      For GIS-based models designed to improve spatial resolution of exposure estimates, Yanosky
et al. (2008, 099467) described three sources from which they derived an estimate of total model
uncertainty: transient model components, stationary model components,  and residual spatial and
temporal components of variance. When analyzing relative contributions to uncertainty, they found
that unexplained local spatial variability was the largest contributor. With model inputs from PMi0
monitors for this study, poor model performance and high uncertainty were observed where monitors
were sparsely located. High uncertainties were also calculated in a few select urban areas (New York
City, Detroit, Cleveland, and Pittsburgh) where concentrations tend to be higher, although the latter
may have been related to the Taylor series approximation used for the residual uncertainty term.
Spatial and temporal uncertainties were also reduced when temporal resolution was increased in the
model implementation.
      In his review of various exposure assessment modeling techniques, Jerrett et al. (2005,
092864) reviewed source proximity and LUR for application to  exposure assessment.  The literature
contains mixed evidence of the association between health effects and source proximity (e.g.,
Langholz et al., 2002, 191771: Maheswaran and Elliott, 2003, 125271; Venn et al., 2000, 007895;
Venn et al., 2001, 023644). Jerrett et al.  (2005, 092864) contend that source proximity modeling is
limited because other confounding covariates, such as SES, may be related to source proximity.
Additionally, subjects' time-activity patterns may vary from locations modeled through source
proximity. Wind direction  and topography may  bring PM plumes away from a site located even in
very close proximity to the source, so that high  concentrations would be  found at distances far
downwind of a source. Jerrett et al. (2005, 092864) state that LUR is an adaptable framework
allowing adaptation to localized conditions, but they caution that LUR is limited to fairly
homogeneous spatial regions. They point to Briggs' (2000, 191772) simulation of Amsterdam as an
example of LUR surfaces produced with little spatial variability.
      LUR and kriging were both used in the ACS data reanalysis by Krewski et al. (2009,  191193)
to study mortality as a function of spatial variability in PM2 5 in New York and Los Angeles, as
described in Section 3.8.3.4.  The LUR solution produced some observed overpredictions near
freeways. Kriged results were compared with LUR for both cities. For New York City, kriging
produced slightly attenuated  mortality risk estimates, while for Los Angeles, kriging did not exhibit
as much spatial variability as LUR. The latter may be due to the fact that the monitoring network in
Los Angeles was not situated to capture spatial variability in PM2.5 concentration occurring near
areas of high traffic. Despite similarities in the LUR performance, health effects predictions  were
quite different for New York City and Los Angeles, with increased hazard ratios of 1.56 and 1.39,
respectively using the same LUR covariates. Krewski et al. (2009, 191193) noted that in New York
City, the healthiest (and wealthiest) segment of the population lived in the most polluted areas, while
in Los Angeles, there was  a strong association between pollution and mortality. This finding implies
that, because geographic regions may differ by multiple factors, such as building and power plant
fuel use, roadway design, traffic patterns, and building design, significant variables in an LUR
analysis may also differ by region.


3.8.6.3.   Spatial  Variability

      For PM, spatial and  temporal distribution as a function of particle size and composition also
plays a large role in the selection of an exposure model. For instance, use of Equation 3-6 might be
employed for a study of ambient PM2.5 exposure because spatial variability in PM2.5 concentration
can be low over urban to regional scales in comparison with more spatially variable PMi0_2.5 and
UFPs, as described in Section 3.8.4. Spatial issues leading to exposure misclassification are
discussed below.
      In panel studies, exposure error will be introduced if the ambient PM concentration measured
at the central site monitor is used as an exposure surrogate and differs from the actual ambient PM
concentration outside a subject's residence and/or worksite. Filleul et al.  (2006, 089862) computed
exposure based on varying contributions of community-based ambient monitors (deemed
background) and proximal monitors (to  represent a receptor) in Le Havre, France for black smoke
measurements. They found that using a weighted mean with increasing weight for proximal  monitors
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resulted in non-significant but increased mean exposure estimates. Moore et al.'s (2009, 191004)
finding of high variability in UFPs across Los Angeles also suggests that exposure error would occur
from using one or a few UFP monitors.  In an example using AQS data, PMi0 monitors in the
Chicago CSA are south of the most populated areas within Chicago (Figure A-8 in Annex A), where
intersampler correlations for urban scale PMi0 data for several monitor pairs are below 0.4 (Table A-
23 in Annex A). In another example from AQS data, PM2.5 and PMi0 monitor locations in the
Riverside CBSA are shown to correspond more closely with higher population density areas (Figures
A-25 and A-26 in Annex A), where urban scale intersampler correlations for both PM2 5 and PMi0 are
below 0.4 for several monitor pairs. For most cities, intersampler correlation is much higher for
PM2.5 than for PMi0. This is in accord with the findings of Sarnat et al. (2009, 180084) where, in an
Atlanta time-series study of the effect of spatial variation in concentration on epidemiologic
associations, spatially homogeneous PM2.5  and O3 were found to be consistently associated with
emergency room visits using any monitor within the study area, while associations were less
consistent across monitors for spatially heterogeneous CO and NO2 among the entire population
studied.  Considering results reported in the literature along with inter-sampler correlations (reported
in Annex A, Section A.2 for PM2 5 and PMi0, and their corresponding monitor locations shown in
Annex A, Section A. 1), the magnitude of spatial  exposure error likely depends on particle size as
well as monitor location, source location, and characteristics such as urban and natural topography
and meteorological trends.
     Spatial variability among various studies further suggests that use of a single or small number
of ambient monitors introduces uncertainty in exposure assessment panel studies. Violante et al.
(2006,  156140) studied personal exposures to traffic of parking police in Bologna, Italy to determine
how personal exposure to outdoor PMi0 and benzene compares with that measured at a
community-based monitor. This study found that personal exposures to PMi0 were significantly
higher than at the community-based monitor, although the authors were not able to demonstrate
significant effects of meteorology or traffic on those exposures. Nerriere et al. (2007, 156801)
observed spatial heterogeneity of personal exposures to metals in PM25 and PMi0, with higher levels
found near high-traffic and industrial areas. In a Bayesian hierarchical model analysis of personal
exposure and ambient PM2 5 data from the pilot Baltimore Epidemiology-Exposure Panel Study of
16 subjects, McBride et al. (2007, 124058) showed that community monitors overestimated personal
exposures for the panel subjects,  and that these results were not sensitive to model selection.
     For community time-series epidemiology,  the community-average concentration, not the
concentration at each fixed monitoring site, is the concentration variable of concern (Zeger et al.,
2000, 001949). Because variation in trends is of interest, bias  in the central site monitor data will not
affect health effects estimates unless the central site monitor is not correlated with the community-
average concentration. The latter condition will cause the health effect estimate to be biased towards
the null (Sheppard et al., 2005, 079176). The correlation between the concentration at a central
community ambient monitor and the community-average concentration depends on homogeneity of
the spatial distribution and representativeness of the central-site monitor location. Kim et al. (2005,
083181) noted that spatial variability among PM species can add uncertainty  to exposure estimates
in community time-series epidemiology studies exploring source contributions to health effects. The
monitoring site is selected to represent the community average of the PM characteristic (mass and/or
species) of interest. If the selected site is far from PM sources, then the average measurement may be
lower than actual ambient PM concentrations. Likewise, if the site is selected to measure a "hot
spot" or pollution from a nearby source, exposure estimates across the community could be skewed
upwards.
     Intra-urban spatial heterogeneity could affect health effects estimates derived from community
time-series studies if a community is divided by urban or natural topographic features or by source
locations into several sub-communities that differ in the temporal pattern of pollution. Intra-urban
spatial  heterogeneity is discussed in detail in Section 3.5. Community exposure may not be well-
represented when monitors cover large areas with several sub-communities having different sources
and topographies. This point is illustrated for Los Angeles in Figure 3-27 and Figure 3-37 where
intersampler correlation decreases with  respect to distance moreso than for other cities shown. Using
zip code classified mortality data in a study of SES and acute  cardiovascular mortality in Phoenix,
high risk ratios were computed when a small area near the monitoring site was studied (Mar et al.,
2003, 156731; Wilson et al., 2007, 157149). while  use of larger-area county-wide data produced
non-significant associations (Moolgavkar, 2000, 010305; Smith et al., 2000, 010335). At least part of
the heterogeneity found between cities in multicity studies may be due to the use of a large
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geographic area that is composed of several sub-communities that differ in the spatiotemporal
distribution of air pollutants. Note that when zip codes cover large areas (e.g., in western mountain
states) or when counties cover small areas (e.g., in the northeast), then assumptions change regarding
use of zip code- or county-level data for epidemiologic studies. For all metropolitan areas
investigated in this assessment, the PMi0 data have significantly more scatter than PM2.5. This
suggests that the uncertainty of the community  average concentration would increase in the coarse
PM range. Metrics have been developed and used to compare the spatial variability of air pollutants
(Wongphatarakul et al., 1998, 049281). These metrics are useful in assessing the potential for
exposure error in the epidemiologic studies, especially when different monitors are used on different
days to construct city-wide averages.
      Epidemiologic studies of long-term exposure rely on differences among communities in long-
term average ambient concentrations. If exposure errors are different in the different communities,
the differences in long-term ambient concentrations among communities may not represent the
differences in long-term average exposures (Dockery et al., 1993, 044457). Thus, in a regression of
health effects against average concentration as an indicator for average exposure, there could be a
different magnitude and direction of error in the exposure indicator for each spatial area. This could
bias the slope up or down. The following epidemiologic studies, described in detail in Section 7.6,
are cited here to illustrate the effect of spatial exposure error on health effects estimates. The Harvard
Six-City Study dealt with this issue by design, where the members of the cohort in each city were
located in a relatively small area near the monitor (Dockery et al., 1993, 044457).  In the ACS study,
the spatial area was the Metropolitan Statistical Area (MSA) (Krewski et al., 2000, 012281); other
studies have used counties as the spatial area (Enstrom, 2005, 087356; Lipfert et al., 2000, 004087).
In a comparison of several of the larger long-term cohort studies, those using county level spatial
areas (Enstrom, 2005, 087356; Lipfert et al., 2000, 004087) sometimes did not find significant
associations, whereas those using MSAs (Pope et al., 1995, 045159; Pope et al., 2002, 024689) or
cities (Dockery et al., 1993, 044457) did find significant associations. Jerrett et al. (2005, 189405)
used smaller zip code areas within Los Angeles County and found effects that were both significant
and largest in magnitude compared to those reported for other long-term cohort studies. Krewski et
al. (2009,  191193) suggested that significant associations between cardiovascular health effects
estimates and PM2.s observed in Los Angeles but not in New York City were related to spatial
homogeneity of PM2.5 concentration in New York City. The Nurses' Health Study examined
associations of mortality with PMi0 and found higher and more significant associations when using
estimated concentrations at subjects' individual residences (Puett et al., 2008,  156891) in lieu of
county-level concentrations (Fuentes et al., 2006, 097647). These considerations suggest that studies
that include large U.S. counties as spatial areas and find no significant associations of health effects
with pollution cannot be considered definitive, because the likelihood of exposure error increases in
this situation. Reducing the exposure error by using concentrations based on residence address or
small zip code areas is associated with larger relative risk than those obtained with county-wide
averages of concentrations.


3.8.6.4.   Temporal Variability


      Temporal Correlation

      Concentration time series analyzed for community time-series  epidemiologic studies can
include those averaged  over several monitors, a single monitor used as an estimate of the true
community average exposure, or a monitor used to represent nearby exposures. Within a city, lack of
correlation of relevant time series at various sites results in smoothing the exposure surrogate
concentration function over time and resulting loss of peak structure from the data series. Burnett
and Goldberg (2003,  042798) found that community time-series epidemiology results reflect actual
population dynamics only when five conditions are met: environmental covariates are fixed spatially
but vary temporally; the probability of the health effect estimate is small at any given time; each
member of the population has the same probability of the health effect estimate at any given time
after adjusting for risk factors; each member of the population is equally affected by environmental
covariates; and, if risk factors are averaged across members of the population, they will exhibit
smooth temporal variation. For this study, mortality was examined, but the temporal considerations
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are generalizable to other health outcomes. Dominici et al. (2000, 005828) note that ensuring
correlation between ambient and community-average exposure time series is made difficult by
limitations in availability and duration of detailed ambient concentration and exposure time series
data and, as a result, is often a source of uncertainty. Sheppard et al. (2005, 079176) also add that the
health effect estimate can be biased by time-dependent error in a in a time-series study if the spatial
variation in PM concentration is not significant. The direction of bias is related to seasonal
correlation between a and Ca.


      Seasonality

      Community time-series studies can be designed to investigate seasonal effects by
incorporating seasonal interaction terms for the exposure surrogate and/or meteorology (e.g.,
Dominici et al., 2000, 005828). Studies from Section 6.5  are briefly mentioned here to illustrate how
seasonal exposures can influence health effect estimates.  Bell et al. (2008, 156266) and Peng et al.
(2005, 087463) observed higher health effect estimates and stronger seasonal dependence  in the
northeast than in the rest of the country for PM2.5 and PMi0, respectively. Peng et al. (2005, 087463)
stated that these results generated three hypotheses. First, the PM composition and resulting toxicity
might vary with season. Bell et al. (2008, 156266) showed seasonal differences between respiratory
and cardiovascular effect estimates that the authors hypothesized related to seasonal differences in
dominance of a given PM species. Second, Peng et al. (2005, 087463) suggested that less  seasonality
in regions other than the northeast may  reflect regional tendencies for spending more or less time
outdoors. Exposure estimates for time spent outdoors may be less subject to exposure error because
uncertainties related to infiltration are not a factor during that time. At the same time, air
conditioning usage, which is more common in the  summer and in warm climates (Pandian et al.,
1998, 090552). has been associated with decreased association between PM2.5 and cardiovascular
morbidity (Bell et al., 2009, 191007). Third, infectious diseases are more prevalent during winter and
so may influence health outcomes. However, it would be expected that regions other than  the
northeast would be affected by influenza in winter. Uncertainty in sources of seasonal bias may also
indicate other unknown factors.


      Data Frequency

      Most panel and many time-series studies examine the associations of health outcomes only
with exposure (or exposure  surrogates)  on the  day  of exposure (lag 0). Zanobetti et al. (2000,
004133) and Lokken et al. (2009, 186774) suggest that health effects may not occur until subsequent
days or be distributed over several days. When PM measurements are obtained every three or six
days,  it is difficult to refine  the study lag structure  down to the day-level. In studies of the  effects of
short-term PM2.5 exposure on cardiovascular and respiratory hospitalization in >200 urban U.S.
counties, Bell et al. (2008, 156266) and Dominici et al. (2006, 088398) worked with a combination
of air  quality measurements obtained daily, those obtained every 3 days, and daily hospitalization
data. Time lags of 0, 1,  and  2 days were applied, such that PM2.5 data obtained only on day 0 would
be applied as lag 0 for the corresponding day's hospitalization record, as lag 1 for the next day's
hospitalization, and as lag 2 for the following day.  No lag 0 data would be available for day 1, and no
lag 0  or 1 data would be available for day 2 in this example. This analysis could be performed with
sufficient statistical power despite the reduction in days of PM data because a large number of
counties were analyzed. Single city studies using data obtained every three or six days could employ
the same approach but would lose statistical power compared with daily data because fewer data
points would exist for each lag. Likewise, Dominici et al. (2006, 088398) only applied distributed
lag analysis to the daily hospitalization  data where daily PM2 5 concentration data were also
available.
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3.8.6.5.   Use of Surrogates for PM Exposure


      Surrogates for Infiltration Tracers

      In panel studies, a tracer can be used for PM that infiltrates indoors, such as sulfate as a
surrogate for PM2.5, as described in Section 3.8.4. For this method to be successful, indoor or other
nonambient sources of the tracer must be small compared to ambient sources over the period of
sampling. Wallace and Williams (2005, 057485) observed that, because SO42~ particles are typically
smaller than other PM contributing to measurable PM2.5 mass, Finf may be biased by using this term
to describe PM2.5 infiltration. Other concerns in using SO42~ as a tracer for PM2.5 arise because SO42~
tends to be concentrated in smaller particles and thus it might be a better tracer for fine mode
particles than for the coarse fraction at the upper tail of the PM25 particle size distribution.
Volatilization of ammonium nitrate or organic compounds after infiltration of PM25 indoors results
in these components being poor surrogates for ambient PM in exposure estimates (Lunden et al.,
2003, 081201).


      Use  of Ambient PM Concentration in Lieu of Ambient PM Exposure

      Ambient PM concentration is often used as a surrogate for exposure to ambient PM in
epidemiologic studies. The ambient concentration may be based on measurements made just outside
the primary microenvironment, at the nearest community monitor, at a single community monitor, or
as the average of several community monitors. Based on the information presented in Section 3.8.4
related to urban-scale PM distribution, there is less exposure error for  accumulation mode PM
because it has a more homogeneous spatial distribution and higher infiltration indoors, compared
with coarse or UFPs. If appropriate measurements are made, it is also  possible to estimate the
ambient and nonambient components of total personal exposure and use four exposure surrogates in
panel epidemiologic studies: Ca, Er, Ea, and Ena (Ebelt  et al., 2005, 056907; Koenig et al., 2005,
087384; Strand et al., 2006, 089203; Wilson and Brauer, 2006, 088933). Results from Wilson and
Brauer (2006, 088933) showed that exposure error is introduced by 1) using Ca instead of Ea and 2)
assuming Ea and Ena have the same effects on health outcomes. There  was essentially no association
of the effect with ET or Ena. Wilson and Brauer (2006, 088933) noted that exposure to nonambient
PM will not affect the relationship between Ca and Ea,  but "the difference between ambient
concentration and ambient exposure will bias the relative risk derived  from epidemiologic studies."
Strand et al. (2006, 089203) also noted that inclusion of nonambient PM25 would not be expected to
change health effect estimates because ambient and nonambient PM2 5 calculations were not
correlated.
      Zeger et al. (2000, 001949) pointed out that for community time-series epidemiology, it is the
correlation of the daily community-average personal exposure to the ambient concentration with
daily community-average concentration that is important, not the correlation of each individual's
daily exposure with the daily community-average concentration. Thus, the low correlation of
individual daily exposure with the daily community-average concentration, as frequently found in
pooled panel exposure studies, is not relevant to error in community time-series  epidemiologic
analysis. Sheppard et al. (2005, 079176) also notes that an insufficient number of total personal
exposure samples used in a time-series design would introduce large classical measurement errors
related to high variability in Ena. Sheppard et al. (2005, 079176)  further maintain that these errors
can be minimized by using the average concentration measured at community-based ambient
monitors. However, overestimation of the community-average exposure by substituting Ca for Ea
leads to underestimation of the effect estimate per unit mass of ambient PM. City-to-city variations
in the indoor air exchange rate, related to differences in climate or housing stock, will cause city-to-
city differences in the health effect endpoint estimate obtained from the study using Ca even if the
endpoint remained the same using the community-average exposure.
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      Relationship between PM and Copollutants

      Uncertainties in the composition of multipollutant mixtures of gases and PM to which the
population is exposed can introduce uncertainties in health effects estimates. When copollutant
associations exist, as described in Section 3.8.5, the potential for one pollutant to act as a surrogate
for another pollutant or mix of pollutants introduces uncertainty into epidemiologic models  (Sarnat
et al., 2001, 019401). For example, O3 may be an indicator of photochemical oxidation products
including organic PM. SO2  may be an indicator of Ni emissions from smelters, V from oil fired
power plants, or As, Se or Hg from coal-fired power plants. In another example, the HEI Report on
traffic-related health effects (2009, 191009) lists CO, NO2, PM2.5 and PMi0 mass, UFP count, EC,
benzene, and traffic metrics (e.g., count, fuel consumption) all as potential surrogates for traffic or
for the mix of all PM and gaseous pollutants in traffic because all of these pollutants are found in
mobile source emissions. Furthermore, in a multipollutant model, transfer of association can occur
by an increase in the slope of a confounding copollutant and a concurrent decrease  in the slope of the
truly causal covariate. This  can occur when copollutants are highly correlated with  larger error for
the true copollutant, smaller error for the confounder, and correlation between the copollutant
measurement errors (U.S. EPA, 2004, 056905: Zeger et al., 2000, 001949; Zidek et al., 1996,
051879). For these reasons, this is an important area of uncertainty for interpretation of the
multipollutant models discussed in Chapter 6.


3.8.6.6.   Compositional Differences

      Differences between  the composition of ambient PM and the ambient PM that has infiltrated
indoors may affect exposure estimates. Numerous differential infiltration studies related to indoor-
outdoor changes in size distribution and chemical composition are cited in Sections 3.8.4 and 3.8.5,
respectively. If differential infiltration results in differences in PM size distribution  and chemical
composition between indoor-ambient PM and outdoor-ambient PM, then use of outdoor-ambient PM
could bias health effects estimates related to particular species. Baxter et al. (2007,  092726) showed
that V tends to have lower F^f, perhaps because metals exist more in the coarse range, while S has
Finf close to unity. Epidemiologic studies cited in Section 6.6  indicate that significant associations
between health effects estimates and PM trace metal exposures exist and may be modified by season.
Trace metal penetration efficiency estimates are thus relevant to those findings. Section 6.6  also
discusses significant associations between health effects endpoints and exposure to EC and  OC in
PM. After initial emission, traffic-related PM is generally in the accumulation mode with volatile
components; accumulation  mode PM tends to have the highest infiltration factors, but volatile
components may be lost during infiltration (Sarnat et al., 2006, 089166). If outdoor residential or
central-site measurements are used for an exposure surrogate, differences in indoor and outdoor PM
composition related to infiltration could introduce uncertainty into effects estimates.
      Ebelt et al. (2005, 056907) illustrated that exposure error occurs when the PM on one or more
days is not representative of the normal community PM. Section 6.3.2.1 discusses this COPD panel
study of the association between respiratory and cardiovascular measures (i.e., lung function, blood
pressure, heart rate, HRV, and ectopic beats) and PM2.5, PMi0_2.5,  and PMi0. In their analysis, one day
of dust from the Gobi Desert caused an increase in the concentration of fine and coarse PM. When
this day was deleted from the analysis, the associations of health effects estimates with PMi0 and
especially with PMi0_2.5 became larger and more significant. Similar peaks in PMi0  concentration
have been observed on the Iberian Peninsula as a result of high transport events carrying dust from
the Sahara Desert that could affect epidemiologic associations on given days (Artinano et al., 2001,
190099).


3.8.6.7.   Conclusions

      This section presents  considerations for exposure assessment and the exposure
misclassification issues that can potentially affect health effects estimates. These issues can  be
categorized into six areas: measurement, modeling, spatial variability, temporal variability, use of
surrogates for PM exposure, and compositional differences. Potential influences of each of these
sources on health effects estimates derived from panel, time-series, and longitudinal epidemiologic
studies are described above. Additionally, error sources often interact with each other and are driven
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by particle size distribution. For example, fresh diesel-generated PM is characterized by UFPs that
dynamically grow and change in chemical composition over short time and spatial scales, and lack
of spatial and temporal resolution in measurements or models can result in misclassifying this
exposure (Moore et al., 2009, 191004). For this reason, conclusions regarding UFP exposure cannot
be drawn from PM2.5 concentration data, in part because PM2.5 concentration is more spatially
homogeneous across a city. In most circumstances, exposure error tends to bias a health effect
estimate downward (Sheppard et al., 2005, 079176: Zeger et al., 2000, 001949). Insufficient spatial
or temporal resolution to capture true variability and correlation of PM with copollutants are
examples of sources of uncertainty that could widen confidence intervals and so potentially reduce
the significance of health effects estimates.
3.9.  Summary and Conclusions
3.9.1.   Concentrations and Sources of Atmospheric PM

      This section summarizes sources and concentrations of atmospheric PM. The following
summaries cover source characteristics from Section 3.3, measurement techniques from Section 3.4,
spacial and temporal variability and copollutant correlations from Section 3.5, source contributions
from Section 3.6 and policy relevant background concentrations from Section 3.7.


3.9.1.1.   PM Source Characteristics

      PM in the atmosphere contains both primary (i.e., emitted directly by sources) and secondary
components, which can be anthropogenic or natural in origin. Secondary components are produced
by the oxidation of precursor gases such as SO2 and NOX and reactions of acidic products with NH3
and organic compounds. Developments in the chemistry of formation of SOA indicate that oligomers
are likely a major component of OC in aerosol samples. Recent observations suggest that small, but
still significant quantities of SOA are formed from isoprene oxidation. Gasoline engines have been
found to emit a mix of OC, EC, and nucleation-mode heavy and large poly cyclic aromatic
hydrocarbons on which unspent fuel and trace metals condense, while diesel particles are composed
of a soot nucleus on which SO42~ and hydrocarbons condense. Data from standard emissions tests in
which there is insufficient dilution of fresh exhaust from combustion sources tend to overestimate
the primary component of organic aerosol at the expense of the semi-volatile components. These
semi-volatile components are precursors to secondary organic aerosol formation and their oxidation
results in more oxidized forms of SOA than previously  considered, both in near source urban
environments and further downwind.


3.9.1.2.   Measurement Techniques

      The federal reference methods for PM2.5 and PM10 are based on criteria outlined in the CFR.
They are, however, subject to several limitations that should be kept in mind when using compliance
monitoring data for health outcome studies. FRM methods are subject to the loss of semi-volatile
species such as organic compounds and ammonium nitrate (especially in the West). Since FRM
gravimetric methods involve 24-h integrated filter samples, no information is available for variations
over shorter averaging times. However, methods have been developed to measure real-time PM2 5 or
PM10 mass concentrations (e.g., FDMS-TEOM). New FRMs and FEMs are available for PM10_2.5 and
various methods (dichotomous samplers, cascade impactors, and passive sampling techniques) are
under evaluation to improve PMi0_2.5 measurements. Techniques are available to characterize UFP
mass, surface area, and number concentrations. Continuous and semi-continuous measurement
techniques are also available for PM species, such as PILS for multiple ion analysis and AMS for
multiple component analysis. Advances have also been achieved in PM organic speciation (e.g., TD-
GC/MS).
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3.9.1.3.   Ambient PM Variability and Correlations

      Advances in understanding the spatiotemporal distribution of PM mass and constituents have
recently been made, particularly with regard to PM2.5 mass and chemical composition and UFP
concentrations. Emphasis in this ISA was on the period 2005-2007 so that the most recent validated
EPA Air Quality System (AQS) data were used. Note, however, that a majority of U.S. counties were
not represented by AQS data since their population fell below the regulatory monitoring threshold
for PM. Moreover, monitors reporting to AQS were not uniformly distributed across the U.S. or
within counties, and conclusions drawn from AQS data may not apply equally to all parts of a
geographic region. Furthermore, biases can exist for some PM constituents (and hence total mass)
owing to volatilization losses of nitrates and other semi-volatile compounds, and, conversely, to
retention of particle-bound water by hygroscopic species. The degree of spatial variability in PM is
likely to be region-specific and strongly influenced by region-specific sources and meteorological
and topographic conditions.


      Spatial Variability across the U.S.

      County-scale, 24-h avg concentration data for PM2.5 between 2005-2007 showed considerable
variability across the U.S.. The highest reported 3-yr avg concentrations were for six counties within
the San Joaquin Valley and inland southern California, as well as Jefferson County, AL (containing
Birmingham) and Allegheny  County, PA (containing Pittsburgh). The lowest reported annual average
PM2.5 concentrations were contained within 237 counties distributed throughout many western and
northern states as  well as Florida and the  Carolinas. Of the 15 individual CSAs/CBSAs selected for
detailed investigation based on their geographic distribution and importance in recent health effect
studies, the highest mean 24-h PM2.5 concentrations were reported for Riverside (17 (ig/m3),
Birmingham (16 (ig/m3) and Pittsburgh (16 (ig/m3); the lowest were reported for Denver (9 (ig/m3)
and Seattle (9 (ig/m3).
      Since PM10_2.5 is not routinely measured and reported to AQS, co-located low-volume PM10
and PM2 5 measurements from the AQS network were used to investigate the spatial distribution in
PMio_2.5. Current data coverage (see Figure 3-10) and measurement errors limit the ability to draw
any meaningful conclusions regarding the large-scale spatial distribution of PMi0_2.5 in urban areas.
Only 6 of the 15 CSAs/CBSAs chosen for closer investigation had sufficient data for calculating
PMio_2.5. In general, in the eastern metropolitan areas including Atlanta, Boston, Chicago and New
York, most of the  mass of PM10 was in the PM25 size fraction, with the  highest ratio of PM25 to
PMio_25in Chicago (14 (ig/m3 PM25 5 (ig/m3 PMio_2s ratio = 2.8). In contrast, Denver (9 (ig/m3
PM2.5, 20 (ig/m3 PMio.2.5, ratio = 0.45) and Phoenix (10 (ig/m3 PM2.5, 22 (ig/m3 PM 10-2.5, ratio = 0.45)
contained most of PMi0 in the thoracic coarse mode.
      Given the limited information available from AQS for PMi0_2.5 and the current National
Ambient Air Quality Standard for PMi0, analyses were performed on the more prevalent PMi0 data
acknowledging that PM10 incorporates both thoracic coarse and fine particles. The highest reported
3-yr avg PMi0 concentrations (>51 (ig/m3) occurred in two counties in southern California and five
counties in southern Arizona and central New Mexico. The lowest reported annual average PMi0
concentrations (<  20 ug/m3) were within  114 counties  distributed fairly uniformly across the U.S. Of
the 15 CSAs/CBSAs investigated, the highest mean 24-h PMi0 concentrations was reported for
Phoenix (52 (ig/m3), considerably higher  than the means for the other CSAs/CBSAs investigated.
The lowest was reported for Boston (17 (ig/m3) with New York, Philadelphia and Seattle only
slightly higher (19 (ig/m3).
      Spatial variability in PM2 5 components obtained from the CSN varied considerably by
species. The highest annual average OC concentrations (>5 (ig/m3) were observed in the western and
southeastern U.S.  Concentrations in the West peaked in the fall and winter, while concentrations in
the Southeast peaked anytime between spring and fall. Of the 15 CSAs/CBSAs investigated, OC was
the dominant PM25 component on an annual basis in the western cities, ranging from 34% of PM25
mass in Los Angeles to 58% in Seattle. EC exhibited less seasonal variability than OC and was
particularly stable in the eastern half of the U.S. Annual average EC concentrations greater than
1.5 (ig/m3 were present in Los Angeles, Pittsburgh, New York and El Paso. Concentrations of SO42~
were higher in the eastern U.S. resulting from higher SO2 emissions in the East compared with the
West. There is also considerable seasonal variability with higher SO42~ concentrations in the summer
months when the oxidation of SO2 proceeds at a faster rate than during  the winter.  Of the 15
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CSAs/CBSAs selected, sulfate was the dominant PM2.5 component on an annual basis in the eastern
cities, ranging from 42% of PM2.5 mass in Chicago to 56% in Pittsburgh. NO3~ concentrations were
highest in California, with annual averages >4 (ig/m3 at many monitoring locations. There were also
elevated concentrations of NO3~ in the Midwest (>2 (ig/m3), with wintertime concentrations
exceeding 4 (ig/m3. In general, NO3~ was higher in the winter across the country, resulting from a
number of factors including: (1) lower temperatures which favor partitioning into particles; (2)
higher relative humidity, mainly in dry areas; (3) lower sulfate, allowing higher uptake of NO3~; and
(4) residential wood burning in specific areas of the U.S., especially in the Northwest. Exceptions
existed in Los Angeles and Riverside, where high NOjT readings appeared year-round. Crustal
material constituted a substantial fraction of PM2.5 year-round in Phoenix (28%) and Denver (16%),
and during the summer in Houston (26%).
      Clearly there are variations in both PM2.5 mass and composition by city resulting from
numerous controlling variables (e.g., meteorology, the nature of sources, proximity to sources,
topography). These variables  are frequently poorly characterized on a broad scale, making it
difficult to draw general conclusions regarding PM2 5 mass and composition across all cities within a
given geographic region.


      Spatial Variability on  the Urban and Neighborhood Scales

      In general, PM2 5 has a longer atmospheric lifetime than PMi0_2.5 because larger particles have
a higher gravitational settling  velocity. For PM2 5, most metropolitan areas exhibited high
correlations (generally >0.75)  between monitoring sites out to a distance of 100 km.  Notable
exceptions were Denver, Los Angeles and Riverside where correlations  dropped below 0.75
somewhere between 20 and 50 km. Insufficient data were available in the 15 metropolitan areas to
perform similar analyses for PMi0_2.s using co-located, low volume FRM monitors. More abundant
PMio data, however, showed larger declines in inter-monitor correlations as a function of distance
relative to PM2 5. Atlanta, Boston, Denver, Los Angeles, New York City, Philadelphia, Phoenix,
Pittsburgh and Riverside all showed an average correlation of 0.75 at 40 km or greater monitor
separation while Birmingham, Chicago, Detroit, Houston and St. Louis had correlations that dropped
off much more quickly with distance (average correlation of 0.75 at 6 km or less monitor separation).
Furthermore, correlations between PMi0 concentrations exhibited substantially more  scatter relative
to PM2 5. Shorter atmospheric  lifetimes for PMi0 can result in local emission sources dominating
PMio annual average mass concentrations at particular monitors. Although the general understanding
of PM differential settling leads to an expectation of greater spatial heterogeneity in the PMio_25
fraction relative to the PM25 fraction in urban areas, deposition of particles as a function  of size
depends strongly on local meteorological conditions, in particular on the degree of turbulence in the
mixing layer. Therefore, the findings from these 15 CSAs/CBSAs may not apply to all locations or at
all times.
      Population density and associated building density are also important determinants of the
spatial distribution of PM concentrations. Inter-sampler correlations as a function of distance
between monitors obtained for sampler pairs located less than 4 km apart (i.e., on a neighborhood
scale) showed a shallower slope for PM25 than for PM10. The average correlation was 0.93 for PM25,
but it dropped to 0.70 for PMi0.
      Few studies have performed direct comparisons  of UFP measurements at multiple  locations
within an urban area. A decrease in the number of UFPs was demonstrated with shifts from a
dominant mode at around 10 nm within 20 m of a freeway to a flattened dominant mode  at around
50 nm at a distance of roughly 100-150 m. At the  same time, accumulation mode particle number
concentration remained relatively constant to within -300 m from the freeway. These findings
suggest a high degree of spatial heterogeneity in UFPs compared with accumulation mode particles
on the urban scale.


3.9.1.4.   Temporal Variability

      A steady decrease in PM2 5 concentrations from 1999 (the beginning of nationwide monitoring
for PM2 5) to 2007 was observed in all 10 EPA Regions, with the 3-yr avg of the 98th percentile of
24-h PM25 concentrations dropping 10% over this time period.  Similar trends in PMio concentrations
show a steady decline from 1988 to 2007 in all 10 EPA Regions.
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      Using hourly PM observations in the 15 metropolitan areas, diel variation showed peaks that
differ by PM size fraction and region. For PM2.5, a morning peak was observed starting at
approximately 6:00 a.m., corresponding with the start of morning rush hour. There was also an
evening PM2 5 concentration peak that was broader than the morning peak and extended into the
overnight period, likely reflecting a combination of evening rush hour and the concentration increase
caused by the usual collapse of the mixed layer after sundown. PM2.5  concentrations in Pittsburgh
remained elevated throughout the night, obscuring the morning peak.  For PM1(j, all areas showed a
morning and afternoon peak in mean concentrations. The magnitude and duration of this peak varied
considerably by metropolitan area.
      Studies indicate that UFPs  in urban environments exhibit similar two-peaked diel patterns in
Los Angeles and the San Joaquin Valley as well as in Kawasaki City, Japan and Copenhagen,
Denmark. The afternoon peak in  UFPs likely represents the combination of primary source
emissions such as evening rush-hour traffic and photochemical formation of secondary organic
aerosol and sulfate. Comparison between weekdays and Sundays as well as an urban street canyon
site and an urban background site in this  figure suggest traffic is a major source of UFPs within a
street canyon during the morning rush hour. Any fluctuations or changes in the timing of the
individual daily peaks during the 3-yr period would result in a broadening of the distribution shown
in the diel plots.


3.9.1.5.   Correlations between Copollutants

      Correlations between PM size fractions and between PM and gaseous copollutants including
SO2, NO2, CO and O3 varied both seasonally and spatially between and within metropolitan areas.
On average, PM10 and PM2 5 were correlated with each other better than with the gaseous
copollutants. Correlations between PMi0 and PMi0_2.5 were greater in all locations than correlations
between PM2 5 and PMi0_2.5. Correlations between PMi0 and PMi0_2.5 were particularly high in
Denver and Phoenix (r > 0.88 in all seasons). There was relatively little seasonal variability in the
mean correlation between PM in  both size fractions and SO2and NO2. CO, however, showed higher
correlations  with PMi0 and PM2 5 on average in the winter compared with the other seasons. This
seasonality results in part because a larger fraction of PM is primary in origin during the winter. To
the extent that this primary component of PM is associated with common sources  of NO2 and CO,
then higher correlations with these gaseous copollutants are to be expected. Increased  atmospheric
stability in colder months would also reinforce these associations. The correlation between daily
maximum 8-h avg O3 and PM showed the highest degree of seasonal variability with positive
correlations  on average in the  spring, summer and fall, and negative correlations on average in the
winter. This situation arises as the result of seasonal differences in PM primary emissions and
photochemical production of secondary PM2 5 and O3
'3-
3.9.1.6.   Source Contributions to PM

      Results of receptor modeling calculations indicate that PM25 is produced mainly by
combustion of fossil fuel, either by stationary sources or by transportation. It is apparent that a
relatively small number of source categories, compared to the total number of chemical species that
typically are measured in ambient monitoring source receptor model studies, are needed to account
for the majority of the observed mass of PM in these studies. Trying to be more specific about
contributions from source categories could result in ambiguity. For example, quite different mobile
sources (e.g., trucks and locomotives) rely on diesel power and ancillary data is required to resolve
contributions from these sources. A compilation of study results shows that secondary sulfate
(mainly from EGUs), nitrate (from the oxidation of NOX emitted mainly from transportation and
EGUs), and primary mobile source categories constitute most of PM25 (and PMi0) in the East.
Fugitive dust, found mainly in the  PMi0_2.5 size range, represents the largest source of ambient PMi0
in many locations in the western U.S. Quoted uncertainties in the source apportionment of
constituents in ambient aerosol samples typically range from 10 to 50%. A comparison of source
apportionment techniques indicated that the same major source categories of PM25 were consistently
identified by several independent groups working with the same data sets. Soil-, sulfate-, residual
oil-, and salt-associated mass were most clearly identified by the groups. Other sources with more
ambiguous signatures, such as vegetative burning and traffic-related emissions were less consistently
identified.
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      Spatial variability in source contributions across urban areas is an important consideration in
assessing the likelihood of exposure error in epidemiologic studies relating health endpoints to
sources. Concepts similar to those for using ambient concentrations as surrogates for personal
exposures apply here. Studies for PM2.5 indicate that intra-urban variability increases in the
following order: regional (e.g., secondary SO42~ from EGUs) < area (e.g., on-road mobile sources)
< point (e.g., stacks) sources. Only one study was available for PMi0_2.5, indicating a similar
ordering, but without a regional component (resulting from the short lifetime of PM10_2.5 compared to
transport times on the regional scale).


3.9.1.7.   Policy-Relevant Background

      The background concentrations of PM that are useful for risk and policy assessments
informing decisions about the NAAQS are referred to as policy-relevant background (PRB)
concentrations. PRB concentrations have historically been defined by EPA as those  concentrations
that would occur in the U.S. in the absence of anthropogenic emissions in continental North America
defined here as the U.S., Canada, and Mexico. For this document, PRB concentrations include
contributions from natural sources everywhere in the world and from anthropogenic sources outside
continental North America. Background concentrations so defined facilitated separation of pollution
that can be controlled by U.S. regulations or through international agreements with neighboring
countries from those that were judged to be generally uncontrollable by the U.S. Over time
consideration of potential  broader ranging international agreements may lead to alternative
determinations of which PM source contributions should be considered by EPA as part of PRB.
Contributions to PRB concentrations of PM include both primary and secondary natural and
anthropogenic components. For this document, PRB concentrations for the continental U.S. were
estimated using EPA's CMAQ modeling system, a deterministic CTM  and with GEOS-Chem, a
global-scale model for CMAQ boundary conditions. PRB concentrations of PM2.5 were estimated to
be less than  1 (ig/m3 on an annual basis, with maximum daily average values in a range from 3.1 to
20 (ig/m3 and having a peak of 63 ug/m3 at the nine national park sites across the U.S. used to
evaluate model performance for this analysis. For further information on methods used in modeling
of PRB concentrations see Section 3.6, and for further information on the results of calculation of
PRB concentrations see Section 3.7.


3.9.2.   Human Exposure

      This section summarizes the findings from the recent exposure assessment literature, which
include the assessment of exposure to ambient PM, infiltration of ambient PM to indoor
environments, and source apportionment of PM exposure. This summary is intended to support the
interpretation of the findings from epidemiologic studies. For more detailed explication see
Section 3.8.


3.9.2.1.   Characterizing Human  Exposure

      A number of techniques have been applied in the literature to model human exposure to PM.
Several studies have used time-weighted microenvironmental models to  define total or ambient PM
exposure.  Time-activity diaries or global positioning systems have been employed to capture the
time-basis for those models. Stochastic population exposure models, such as APEX and SHEDS, are
applied for PM exposure risk assessment among the population. Concentrations from chemistry
transport models have also been used to provide input to the stochastic exposure models at particular
locations.  LUR models have been applied for individual exposures at the intra-urban scale to
examine exposure to pollution surrogates, such as traffic counts, land use, or topographic variables.
Source proximity and kriging have also been applied. GIS-based models have been  used to model
exposure over large regions (e.g., for the Nurse's Health Study) using spatial smoothing models of
AQS data and incorporating GIS-based and meteorological covariates. GIS approaches have also
been used for intra-urban scale exposure studies. These methods all have their own uses and caveats.
LUR is an adaptable framework allowing adaptation to localized conditions but might best be
applied in relatively spatially homogeneous areas. In a comparison of LUR with kriging, kriging
produced slightly attenuated mortality risk estimates for New York City,  while for Los Angeles,
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kriging did not exhibit as much spatial variability as LUR. Source proximity modeling is relatively
simple to apply but is limited because other confounding covariates, such as socioeconomic status,
may be related to source proximity. Additionally, source proximity models do not incorporate time-
activity data.
      New advancements in personal and microenvironmental monitoring techniques have been
reported. Personal monitoring developments include new models of cascade impactors and cyclones
to sample in the UF  size range and miniature monitors for species detection. Additionally, new work
on microenvironmental modeling using mobile platforms and GPS technology has been reported.
The reader is referred to the 2004 PM AQCD (U.S. EPA, 2004, 056905) for descriptions of most
real-time and filter-based personal and microenvironmental PM monitors currently available.


3.9.2.2.   Spatial Scales of PM Exposure Assessment

      Assessing population-level exposure at the urban scale is particularly relevant for time-series
epidemiologic studies, which provide information on the relationship between health effects and
community-average exposure, rather than variations in individual exposure. The correlation between
the PM concentration measured at a central-site community ambient monitor and the true community
average concentration depends on the spatial distribution of the PM, location of the monitoring site
chosen to represent the community average, and division of the community by terrain features or
source locations into several sub-communities that differ in the temporal pattern of pollution.
Concentrations of SO42~ and some components of SOA measured at central-site monitors are
expected to be uniform in urban areas given the regional nature of their sources. However, this is not
true for primary components like EC whose sources are strongly  spatially variable in urban areas.
Given that  roughly 90% of an individual's day is spent indoors, assessment of exposure  to infiltrated
ambient SO42~, whose formation and dispersion also occurs over urban-to-regional scales and whose
size distribution is in the accumulation mode, is  commonly used to assess ambient PM2.5 exposure.
This technique has also been applied to assess PMi0_2.5 exposure but likely with more error than for
PM2.5 because PMi0_2.5 is  more highly spatially variable than PM2 5. Source apportionment techniques
have also been applied to assess urban-scale PM2 5 exposures using community-based ambient
monitoring, outdoor, and indoor samples.
      At micro-to-neighborhood scales, heterogeneity of sources and topography may cause more
variability in exposure. This  is particularly true for PMi0_2.5 and for UFPs, both of which are more
highly spatially variable than PM2 5 Particle chemistry and source behavior also contribute to  spatial
heterogeneity of PM concentration. Some studies, conducted mainly in Europe, have found personal
PM2 5 and PMi0 exposures for pedestrians in street canyons to be higher than ambient concentrations
measured by urban background ambient monitors. Likewise, microenvironmental UFP
concentrations were observed to be substantially higher in near-road environments, street canyons,
and tunnels when compared with other environments in urban areas. In-vehicle UFP exposures can
also be important. As a result, ambient monitors  located at background, central urban, road side, or
near-residential sites might not reflect peak exposures to individuals who commute.
      PM infiltration factors, F^f, depend on particle size, chemical composition, season, and region
of the country. Infiltration can best be modeled dynamically based on a distribution of air exchange
and deposition PM loss rates rather than being represented by a single value. There is significant
variability within and across regions of the country with respect to indoor exposures to ambient PM.
Infiltrated ambient PM concentrations depend in part on the ventilation properties of the building or
vehicle in which the person is exposed.  Season is important to  PM infiltration because it affects the
ventilation  practices used, and ambient temperature and humidity conditions affect the transport,
dispersion, and size  distribution of PM. Residential air exchange  rates have been observed to be
higher in summer for regions with low air conditioning usage,  and regional differences in air
exchange rates (Southwest < Southeast < Northeast < Northwest) also reflect ventilation practices.
Differential infiltration occurs as a function of PM size and composition. PM infiltration is largest
for accumulation mode particles, and decreases for UFPs lost to diffusion and for coarse PM lost
through inertial impaction mechanisms. Differential infiltration by size fraction can affect exposure
estimates if not properly characterized.
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3.9.2.3.   Multicomponent and Multipollutant PM Exposures

      Emission inventories and source apportionment studies suggest that sources of PM exposure
vary by region. Comparison of studies performed in the eastern U.S. with studies performed in the
western U.S. suggest that the contribution of SO42~ to personal exposure is higher for the East
(16-46%) compared with the West (-4%) and that motor vehicle emissions and secondary NO3" are
larger sources of personal exposure for the West (-9%) as compared with the East (-4%). Results of
source apportionment studies of personal exposure to SO^ indicate that personal SO^ exposures
are mainly attributable to ambient sources. Source apportionment for OC and EC is difficult because
they originate from both indoor and outdoor sources. Exposure to OC of indoor and outdoor origin
can be distinguished by the presence of aliphatic C-H groups generated indoors, since outdoor
concentrations of aliphatic C-H are low. Trace metal studies have shown variable results regarding
personal  exposure to ambient constituents with significant variation among cities and over seasons
that can be related to incinerator operation, fossil fuel combustion, biomass combustion (wildfires),
and presence of crustal materials in the built environment, among other sources. Differential
infiltration is also affected by variations in particle composition and volatility. For example EC
infiltrates more readily than OC. This can lead to outdoor-indoor differentials in PM toxicity.
      A number of studies have  examined whether gaseous  copollutants could act as surrogates for
exposure to ambient PM. Several studies have concluded that ambient concentrations of O3, NO2,
and SO2 are associated with the ambient component of personal exposure to  total PM2.5 as opposed
to the ambient component of personal exposures to the gases. However, in some studies this result
may have arisen in part because  personal exposure to the gases was often beneath the detection
limits of the personal monitoring devices. Thus, the evidence that ambient gases can be considered
surrogates of PM2.5 exposure is mixed. It is likely that associations between ambient gases and
personal  exposure to PM2 5 of ambient origin exist, but they are complex and vary by season and
location.


3.9.2.4.   Implications for Epidemiologic Studies

      The importance of exposure error varies with study design based on the spatial and temporal
aspects of the design. For PM epidemiology  studies, source characteristics, particle size distribution,
and particle composition are also important factors in interpreting exposure error for an
epidemiology study. Potential sources of error that could influence estimates of PM exposure include
measurements, use of surrogates for PM exposure, modeling, spatial variability, temporal variability,
and compositional differences.
      PM exposure estimates are subject to monitoring and modeling errors. Ambient and personal
exposure monitoring errors can bias health effects estimates if the error is strongly correlated with
the measurements of concentration. This can be an issue for sampling semi-volatile organic
compounds in PM, especially where PM exposures in cities with different PM  composition are
compared. Ambient monitor height also affects estimates of exposure because PM concentration
varies as  a function of height. Within a street canyon, changes in wind direction and speed cause
significant variability over a small distance. Wind tunnel studies have shown street canyon effects
exist for suburban settings as well as for heavily urbanized settings. Additionally, model-based
exposure estimates are subject to errors related to the spatial resolution of the modeling technique
and the measurement-based inputs used.
      Variations in PM and its components could lead to errors in using ambient PM measures as
surrogates for PM exposure. PM2 5 concentrations are relatively well-correlated across monitors in
the urban areas examined. Correlation coefficients tend to be lower, and concentration differences
tend to be higher between PMi0 monitoring sites than between PM2 5 monitoring sites. Likewise,
studies have shown UFPs to be more spatially variable across urban areas. Even if PM25, PMi0_2.5,
and UFP  concentrations measured at sites within an urban area are highly correlated, significant
differences in their concentrations can occur on any given day. The degree of urban-scale spatial
variability in PM concentrations varies across the country and with size fraction. Current information
suggests that UFPs, PMi0_2.5s and many PM components are more spatially variable than PM2 5. These
factors should be considered in using data obtained from monitoring networks  to estimate
community-scale human exposure to ambient PM, and caution should be exercised in extrapolating
conclusions obtained from one urban area to another.
December 2009                                 3-191

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      Community time-series epidemiologic studies use the average community PM concentration
as a surrogate for the average personal exposure to ambient PM. The resulting health effect risk
estimate, based on the average community ambient concentration, differs from the risk that would be
estimated if the average community ambient exposure were used in the epidemiologic study.
However, the risk estimate based on the ambient concentration gives the change in health effects
resulting from a change in ambient PM concentration and is, therefore, an appropriate measure for
risk assessment and risk management. Variations in ambient concentrations across a community,
variations in individual ambient exposures around the community average, and seasonal or daily
variation in the ambient exposure estimate may increase standard errors of PM health effects
estimates, making it more difficult to detect a true underlying association between the correct
exposure metric and the health outcome studied. Likewise, sampling time interval and lag time
selection both determine whether an epidemiologic model captures the phenomena of interest with
sufficient resolution. The use of the community average ambient PM2.5 concentration as a surrogate
for the community average personal exposure to ambient PM2.5 is not expected to change the
principal conclusions from PM2 5 epidemiologic studies that use community average health and
pollution data. Several recent studies support this by showing how the ambient component of
personal exposure to PM2.5 could be estimated using various tracer and source apportionment
techniques and that it is highly correlated with ambient  concentrations of PM2 5. These studies also
show that the non-ambient component of personal exposure to PM25 is basically uncorrelated with
ambient PM2 5 concentrations. For long-term studies that use differences in long-term community
average ambient  PM concentrations as an exposure metric, the effect of possible community-to-
community differences in the average ambient exposure factor or in the average non-ambient
exposure are less understood. For panel  epidemiologic studies, the most appropriate exposure metric
may depend on the health outcome measured. However, sufficient information should be obtained to
enable determining the association of the health outcome with ambient concentration, ambient
exposure, non-ambient exposure, and total personal exposure.
      Exposure error may occur if a measured PM component acts as a surrogate for another PM
constituent. Differences between composition of outdoor and indoor ambient PM may also cause
error in exposure assessment related either to differential losses of UF or coarse PM from diffusion,
evaporation of semi-volatile PM, or impaction. The resulting differences in PM size distribution and
chemical composition between  indoor-ambient PM and outdoor-ambient PM are expected to cause
differences in toxicity that could affect health outcomes. Lack of information regarding these
relationships adds uncertainty to the health effects estimate.
December 2009                                 3-192

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                        Chapter  4.  Dos i me try
4.1.  Introduction

      Particle dosimetry refers to the characterization of deposition, translocation, clearance, and
retention of particles and their constituents within the respiratory tract and extrapulmonary tissues.
This chapter summarizes basic concepts presented in dosimetry chapters of the 1996 and 2004 PM
AQCDs (U.S. EPA, 1996,  079380: U.S. EPA, 2004, 056905). and updates the state of the science
based upon new literature  appearing since publication of these PM AQCDS. Although the basic
understanding of the mechanisms governing deposition and clearance of inhaled particles has not
changed, there is significant additional information on the role of certain biological determinants
such as gender, age and lung disease on deposition  and clearance. Additionally, new studies have
further characterized the retention and translocation of ultrafine particles (UFPs; also commonly
referred to as nanoparticles) following deposition in the respiratory tract.
      The dose from inhaled particles deposited and retained in the respiratory tract is governed by a
number of factors. These include exposure concentration and duration, activity and ventilatory
parameters, and particle properties  (e.g., particle size, hygroscopicity, and solubility in airway fluids
and cellular components).  The basic characteristics of particles as they relate to deposition and
retention, as well as anatomical and physiological factors influencing particle deposition and
retention, were  discussed in depth in Chapter 10 of 1996 PM AQCD  and updated in Chapter 6 of the
2004 PM AQCD.  Species  differences between humans and rats in particle exposures, deposition
patterns, and pulmonary retention were also reviewed in Brown et al. (2005, 089308). The current
review of PM dosimetry focuses mainly on issues that may affect the susceptibility of an individual
to adverse effects as well as issues that  affect our ability to extrapolate findings between studies
(e.g., in vitro to in vivo) and between species. Other than a brief overview in this introductory
section, the disposition (i.e., deposition, absorption, distribution, metabolism, and elimination) of
fibers and unique nano-objects (viz., dots, hollow spheres, rods, fibers, tubes) is not reviewed herein.
Substantial exposures to fibers and unique nano-objects generally occur in the occupational settings
rather than the ambient environment.
      The deposition by interception of micro-sized fibers was briefly  discussed in the 1996 and
2004 PM AQCD, but fiber retention in the respiratory tract was not addressed. Airborne fibers
(length/diameter ratio > 3), can exceed  150 um in length and appear to be relatively stable in air.
This is because their aerodynamic size is determined predominantly by their diameter, not their
length. Fibers longer than  10 um can deposit by interception and when aligned with the direction of
airflow may penetrate deep into the respiratory tract. Once deposited, macrophage mediated
clearance is the primary mechanism of removing micro-sized particles from the pulmonary region.
The length of fibers can, however, affect their phagocytosis and clearance. For example, fibers of
>17  um in length are too long to be fully engulfed by rat alveolar macrophages and can protrude
from macrophages (i.e., macrophage frustration) (Zeidler-Erdely et al., 2006, 190967). Further
discussion of the fiber disposition in the respiratory tract is beyond the scope of this chapter.
      The term "ultrafine particle" has traditionally been used by the aerosol research and
occupational and environmental health  communities to describe airborne particles or other laboratory
generated aerosols used in toxicological studies that are <100 nm in size (based on physical size,
diffusivity, or electrical mobility). Generally consistent with the definition of an UFP, the
International Organization for Standardization (ISO) recently defined a nanoparticle as an object
with all 3 external  dimensions in the nanoscale, i.e., from approximately 1 and 100 nm (ISO, 2008,
190066). The ISO  also defined a nano-object as a material with one or more external dimensions in
 Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
 Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
 developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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the nanoscale. The terms, nanoparticle and UFP, have been used rather synonymously in the recent
literature. However, the terms nanoparticle and nano-object are more commonly associated with
engineered materials that are created for consumer products and industrial applications. With the
current interest in nanotechnologies, many nano-objects have been created by manipulating materials
at the atomic or molecular scale for the purpose of forming new materials, structures, and devices
that exploit the unique physical and chemical properties associated with their nanoscale.
Toxicological studies are becoming available that evaluate in vivo translocation and heath effects
unique of nano-obj ects (viz., dots, hollow spheres, rods, tubes). The in vivo disposition of these
unique nano-objects is not, however, necessarily relevant to the behavior of UF aerosols in the urban
environment that are created by combustion sources and photochemical formation of secondary
organic aerosols. Therefore, the disposition of unique nano-objects (viz., dots, hollow spheres, rods,
fibers, tubes) is not considered in this chapter.


4.1.1.  Size Characterization of Inhaled  Particles

      Particle size is a major determinant of the fraction of inhaled particles  depositing in and
cleared from various regions of the respiratory tract. The distribution of particle sizes in an aerosol is
typically described by the lognormal distribution (i.e., the  situation in which the logarithms of
particle diameter are distributed normally). The geometric mean is the median of the distribution,
and the variability around the median is the geometric standard deviation (GSD or og) and is given
by:


                                GSD = o-   = ii% =^o%
                                               "50%    "16%
                                                                                    Equation 4-1

where: di6%, d50%, d84% are the particle diameters associated with the 16th, 50th (i.e., the median), and
the 84th percentiles from the cumulative frequency distribution of particle sizes. By definition, GSD
must be greater than one. The particle size associated with any percentile of the distribution, di, is
given by:

                                      d  = ^o% ff*(P)

                                                                                    Equation 4-2

where: z(P) is the normal standard deviate for a given probability. In most cases, the aerosols to
which people are naturally exposed are poly disperse. By contrast, most experimental studies of
particle deposition and clearance in the lung use monodisperse particles (GSD <1.15). Ambient
aerosols may also be composed of multiple size modes, each mode should be described by its
specific median diameter and GSD.
      Aerosol size distributions may be measured and described in various ways. When a
distribution is described by counting particles, the median is called the count median diameter
(CMD). On the other hand, the median of a distribution based on particle mass in an aerosol is the
mass median diameter (MMD). Impaction and sedimentation of particles in the respiratory tract
depend on a particle's aerodynamic diameter (dae), which is the size of a sphere of unit density that
has the same terminal settling velocity as the particle of interest. The size distribution is frequently
described in terms of dae as the mass median aerodynamic diameter (MMAD), which is the median
of the distribution of mass with respect to aerodynamic equivalent diameter. Alternative descriptions
should be used for particles with actual physical sizes below ~ 0.5 urn because, for these sized
particles, aerodynamic properties become less important and diffusion becomes ever more important.
For these smaller particles, their physical diameter or CMD are typically used since diffusivity  is not
a function of particle density. For small irregular shaped particles and aggregates, the diameter  of a
spherical particle that has the same diffusion  coefficient in air as the particle in question is
appropriate.
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4.1.2.  Structure of the Respiratory Tract

      The basic structure of the human respiratory tract is illustrated in Figure 4-1. In the literature,
the terms extrathoracic (ET) region and upper airways are used synonymously. The term lower
airways is used to refer to the intrathoracic airways, i.e., the combination of the tracheobronchial
(TB) region which is the conducting airways and the alveolar region which is the functional part or
parenchyma of the lung. A recent review of interspecies similarities and differences in the structure
and function of the respiratory tract is provided by Phalen et al. (2008, 156865). Although the
structure varies, the illustrated anatomic regions are common to all mammalian species with the
exception of the respiratory bronchioles. Respiratory bronchioles, the transition region between
ciliated and fully alveolated airways, are found in humans, dogs, ferrets, cats, and monkeys.
Respiratory bronchioles are absent in rats and mice and abbreviated in hamsters, guinea pigs, oxen,
sheep, and pigs. The branching structure of the ciliated bronchi and bronchioles also differs between
species from being a rather symmetric and dichotomous branching network of airways in humans to
a more monopodial branching network in other mammals.
            Extrathoracic
               Region
                Posterior
                Nasal Passage

              fNasal Part
       Pharynx-^  -. .....
           '   [  Oral Part
                                  Trachea
           Tracheobronchial
               Region
                Main Bronchi

                  Bronchi


               Bronchioles
                                                                      Bronchiolar Region

                                                                      Alveolar Interstitial
              Alveolar
               Region
                                                           Bronchioles
                                                             Terminal Bronchioles
                                                          Respiratory Bronchioles
                                                         Alveolar Duct +
                                                         Alveoli
                                                                         Source: Based on ICRP (1994,;
Figure 4-1.
Diagrammatic representation of respiratory tract regions in humans.  Structures
are anterior nasal passages, ETi; oral airway and posterior nasal passages, ET2;
bronchial airways, BB; bronchioles, bb; and alveolar interstitial, Al.
      Another species difference relevant to particle dosimetry is the route of breathing. For
instance, rodents are obligate nose breathers, whereas most humans are oronasal breathers who
breathe through the nose when at rest and increasingly through the mouth with increasing activity
December 2009
                                4-3

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level. There is inter-individual variability in the route by which people breathe. Most people, 87%
(26 of 30) in the Niinimaa et al. (1981, 071758) study, breathed through their nose until an activity
level was reached where they switched to oronasal breathing. Thirteen percent (4 of 30) of the
subjects, however, were oronasal breathers even at rest. These two subject groups are commonly
referred to in the literature (e.g. ICRP, 1994, 006988) as "normal augmenters" and "mouth
breathers," respectively. In contrast to healthy subjects, Chadha et al. (1987, 037365) found that the
majority (11 of 12) of patients with asthma or allergic rhinitis breathe oronasally even at rest.
                   a.
                           Bronchus
                                            Bronchiolus
                                                                Aveolus
                   b.
                             Air
                            Liquid
                            Tissue
 Air
Tr 11 n
Liquid
                                             Tissue
                                                                 Air
                                                                 Air
                                           Source: Panel (a) reprinted with permission from McGraw Hill (Fishman and Elias, 1980,156436)
Figure 4-2.     Structure of lower airways with progression from the large airways to the
               alveolus. Panel (a) illustrates basic airway anatomy.  Structures are epithelial
               cells, EP; basement membrane, BM; smooth muscle cells, SM; and
               fibrocartilaginous coat, FC. Panel (b) illustrates the relative amounts of liquid,
               tissue, and blood with distal progression.
December 2009
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      The site of particle deposition within the respiratory tract has implications related to lung
retention and surface dose of particles as well as potential systemic distribution of particles or their
constituents. Figure 4-2 illustrates the progressive change in airway anatomy with distal progression
into the lower respiratory tract. In the bronchi there is a thick liquid lining and mucociliary clearance
rapidly moves deposited particles toward the mouth. In general, in the bronchi, only highly soluble
materials moving from the air into the liquid layer will have systemic access via the blood. With
distal progression, the protective liquid lining diminishes and clearance rates slow.  Soluble
compounds and some poorly soluble UFPs may cross the air-liquid interface to enter the tissues and
the blood especially in the alveolar region.
4.2.  Particle  Deposition
      Inhaled particles may be either exhaled or deposited in the ET, TB, or alveolar region. A
particle becomes deposited when it moves from the airway lumen to the wall of an airway. The
deposition of particles in the respiratory tract depends primarily on inhaled particle size, route of
breathing (nasal or oronasal), tidal volume (VT), breathing frequency (f), and respiratory tract
morphology. The distinction between air passing through the nose versus the mouth is important
since the nasal passages more effectively remove inhaled particles than the oral passage. Respiratory
tract morphology, which affects particle transport and deposition, varies between species,  the size of
an animal or human, and health status.
      The fraction of inhaled aerosol becoming deposited in the human respiratory tract has been
measured experimentally. Studies, using light scattering or particle counting techniques to quantify
the amount of aerosol in inspired and expired breaths, have characterized total particle deposition for
varied breathing conditions and particle sizes. The vast majority of in vivo data on the regional
particle deposition has been obtained by scintigraphic methods where external monitors are used to
measure gamma emissions from radiolabeled particles. These scintigraphic data have shown highly
variable regional deposition with sites of highly localized  deposition or "hot spots" in the  obstructed
lung relative to the healthy lung. Even in the healthy lung, "hot spots" occur in the region of airway
bifurcations. Mathematical models aid in predicting the mixed effects of particle size, breathing
conditions, and lung volume on total and regional deposition. Experimentally, however, there is
considerable inter-individual variability in total and regional deposition even when inhaled particle
size and breathing conditions are strictly controlled. Section 4.2.4 on Biological Factors Modulating
Deposition provides more detailed information on factors  affecting deposition among individuals.
      In order to potentially become deposited  in the respiratory tract, particles must first be inhaled.
The inspirable particulate mass fraction of an aerosol is that fraction of the ambient airborne particles
that can enter the uppermost respiratory tract compartment, i.e., the head (Soderholm,  1985,
156992). The American Conference of Governmental Industrial Hygienists (ACGIH) and the
International Commission on Radiological Protection (ICRP) have established inhalability criteria
for humans (ACGIH, 2005, 156188: ICRP, 1994, 006988). These criteria are indifferent to route of
breathing and assume random orientation with  respect to wind direction. They are based on
experimental inhalability data for dae < 100 um at wind speeds of between 1 and 8 m/s. For the
ACGIH criterion, inhalability is 97% for an dae = 1 um, 87% for an dae = 5 um, 77% for an
dae = 10 um, and plateaus at 50% for dae above  -40 um. The ICRP criterion, which also plateaus at
50% for very large dae,  does not become of real importance until an dae = 5 um where inhalability is
97%. Dai et al.  (2006, 156377) reported slightly lower nasal particle inhalability in humans during
moderate exercise than rest (e.g., 89.2 versus 98.1% for 13 um particles, respectively). Nasal particle
inhalability is similar between an adult and 7-year-old child (Hsu and Swift, 1999, 155855).
Inhalability into the mouth from calm air in humans also becomes important for dae >10 um
(Anthony and Flynn, 2006, 155659; Brown, 2005, 156299). Unlike the inhalability from  high wind
speeds which plateaus at 50% for dae greater than ~40 um, particle inhalability from calm air
continues to decrease toward zero with increasing dae.
      Inhalability data in laboratory animals, such as rats, are only available for breathing from
relatively calm  air (velocity < 0.3 rn/s). For nasal breathing, inhalability  becomes an important
consideration for dae of above 1  um in rodents and 10 um  in humans (Menache et al., 1995, 006533).
The inhalability of particles having dae of 2.5, 5, and 10 um is 80, 65, and 44% in rats, respectively,
whereas it only decreases to 96% for an dae of 10 um in humans during nasal breathing (Menache et
December 2009                                  4-5

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al., 1995, 006533). Asgharian et al. (2003, 153068) suggested that an even more rapid decrease in
inhalability with increasing dae may occur in rats. Inhalability is a particularly important
consideration for rodent exposures. Section 4.2.3 provides additional discussion of interspecies
patterns of particle deposition.


4.2.1.  Mechanisms of Deposition

      Particle deposition in the lung is predominantly governed by diffusion, impaction, and
sedimentation. Most discussion herein focuses on these three dominant mechanisms of deposition.
Simple interception, which is an important mechanism of fiber deposition, is not discussed in this
chapter. Electrostatic and thermophoretic forces as mechanisms of deposition have not been
thoroughly evaluated and receive limited discussion.  Some generalizations with regard to deposition
by these mechanisms follows, but should not be viewed as absolute rules. Both experimental studies
and mathematical models have demonstrated that breathing patterns  can dramatically alter regional
and total deposition for all sized particles. The combined processes of aerodynamic and diffusive (or
thermodynamic) deposition are important for particles in the range of 0.1 um to 1 um. Aerodynamic
processes predominate above and thermodynamic processes predominate below this range.
      Diffusive deposition, by the process of Brownian diffusion,  is  the primary mechanism of
deposition for particles having physical diameters of less than 0.1  um. For particles having physical
diameters of roughly between 0.05 and 0.1 urn, diffusive deposition  occurs mainly in the small distal
bronchioles and the pulmonary region of the lung. However, with further decreases in particle
diameter below -0.05 um, increases in particle diffusivity shift more deposition proximally to the
bronchi and ET regions.
      Governed by inertial or aerodynamic properties, impaction and sedimentation increase with
dae. When a particle has sufficient inertia, it is unable to follow changes in flow direction and strikes
a surface thus depositing by the process of impaction. Impaction occurs predominantly at
bifurcations in the proximal airways, where linear velocities and secondary eddies are at their
highest. Sedimentation, caused by the gravitational settling of a particle, is most important in the
distal airways and pulmonary region of the lung. In these regions,  residence  time is the greatest and
the distances that a particle must travel to reach the wall of an airway are minimal.
      The electrical charge on some particles may result in an enhanced deposition over what would
be expected based on size alone. With an estimated charge of 10-50 negative ions per 0.5 um
particle, Scheuch et al. (1990, 006948) found deposition in humans (VT = 500 mL, f = 15 min"1) to
increase from 13.4% (no charge) to 17.8% (charged). This increase in deposition is thought to result
from image charges induced on the surface of the airway by charged particles. Yu (1985, 006963)
estimated a charge threshold level above  which deposition fractions would be increased of about 12,
30, and 54% for 0.3, 0.6, and 1.0 um diameter  particles, respectively. Electrostatic deposition is
generally considered negligible for particles below 0.01 um because so few of these particles carry a
charge at Boltzmann equilibrium. This mechanism is also thought  to be a minor contributor to
overall particle deposition, but it may be important in some laboratory studies due to specific aerosol
generation techniques such as nebulization. Laboratory methods such as passage of aerosols through
a Kr-85 charge neutralizer prior to inhalation are commonly used to mitigate this effect.
      The National Radiological Protection Board (NRPB) recently  evaluated the potential for
corona discharges from high voltage power lines to charge particles and enhance particulate doses
(NRPB, 2004, 156815). They concluded that electrostatic effects would be the most important for
particles in the size range from about 0.1-1 um, where deposition may theoretically increase by a
factor of three to ten. However, given that only a small fraction of ambient particles would pass
through the corona to become charged, the small range of relevant particle sizes (0.1-1  um), and the
subsequent required transport of charged particles to  expose individuals;  the NRPB concluded that
effects, if any, of electric fields on particle deposition in the human respiratory tract would likely be
minimal.
      Thermophoretic forces on particles occur due to temperature differences between respired air
and respiratory tract surfaces. Temperature gradients  of around 20°C are thought to produce
sufficient thermophoretic force to oppose diffusive and electrostatic deposition during inspiration
and to perhaps augment deposition by these mechanisms during expiration (Jeffers, 2005, 156608).
Thermophoresis is only relevant in the extrathoracic and large bronchi airways and reduces to zero
as the temperature gradient decreases deeper in the lung. Theoretical analysis of thermophoresis has
been done for smooth walled tubes and is important over distances that are several orders of
December 2009                                  4-6

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magnitude smaller than the diameter of the trachea. The alteration of the flow patterns by airway
surface features such as cartilaginous rings may affect particle transport and deposition over far
greater distances than thermophoretic force.
4.2.2.  Deposition Patterns
      Knowledge of sites where particles of different sizes deposit in the respiratory tract and the
amount of deposition therein is necessary for understanding and interpreting the health effects
associated with exposure to particles. Particles deposited in the various respiratory tract regions are
subjected to large differences in clearance mechanisms and pathways and, consequently, retention
times. Deposition patterns in the human respiratory tract were described in considerable detail in
dosimetry chapters of prior PM AQCD (U.S. EPA, 1996, 079380: U.S. EPA, 2004, 056905): as such,
they are only briefly described here.
      Predicted total and regional deposition for an adult male during rest and light exercise are
illustrated in Figure 4-3 and Figure 4-4, respectively. Note that a large proportion of inhaled coarse
particles in the 3-6 um (dae) range can reach and deposit in the lower respiratory tract, particularly
the TB airways. Although these figures were provided in Chapter 6 of the 2004 PM AQCD, they are
reproduced here to illustrate changes in deposition as a function of particle size and breathing
conditions. The predictions were based on two publicly available particle deposition models, the
ICRP (1994, 006988) and the Multi-Path Particle Dosimetry model (MPPD; Version 1.0, ©2002).
The ICRP (1994, 006988) model was implemented by Lung Dose Evaluation Program (LUDEP;
Version 2.07, June 2000). The MPPD1 model was developed by the CUT Centers for Health
Research with support from the Dutch National Institute of Public Health and the Environment.
                       0.1          1
                         Diameter, |jm
               0.1           1
                 Diameter, |jm
Figure 4-3.    Comparison of total and regional deposition results from the ICRP and MPPD
              models for a resting breathing pattern (VT = 625 ml, f = 12 min"1) and corrected
              for particle inhalability. Regions are extrathoracic,  ET; tracheobronchial, TB; and
              alveolar, A. Panels a-b are for nose breathing; panels c-d are for mouth breathing.
1 For more information about this model, the reader is referred to: http://www.ara.com/products/mppd capabilities.htm.
December 2009
4-7

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           1.0
                         Diameter,
                  Diameter, \im
Figure 4-4.    Comparison of total and regional deposition results from the ICRP and MPPD
              models for a light exercise breathing pattern (VT = 1250 ml, f = 20 min"1) and
              corrected for particle inhalability. Regions are extrathoracic, ET;
              tracheobronchial, TB; and alveolar, A. Panels a-b are for nose breathing; panels
              c-d are for mouth breathing.
4.2.2.1.   Total Respiratory Tract Deposition

      The efficiency of deposition in the respiratory tract may generally be described as a
"U-shaped" curve on a plot of deposition efficiency versus the log of particle diameter. Total
deposition shows a minimum for particle diameters in the range of 0.1 to 1.0 um, where particles are
small enough to have minimal sedimentation or impaction and sufficiently large so as to have
minimal diffusive deposition. Total deposition does not decrease to zero for any sized particle, in
part, because of mixing between particle laden tidal air and residual lung air. The particles mixed
into residual air remain in the lung following a breath and are removed on subsequent breaths or
gradually deposited. Total deposition approaches 100% for particles of roughly 0.01  um (physical
diameter) due to diffusive deposition and for particles of around 10 um (dae) due to the efficiency of
sedimentation and impaction.
      Total human lung deposition, as a function of particle size, is depicted in Figure 4-5. These
experimental data were obtained by using monodisperse spherical test particles in healthy adults
during controlled breathing on a mouthpiece. Despite the control of inhaled particle size and
breathing conditions, this figure illustrates variability in deposition efficiencies due to inter-
individual differences in lung size and anatomical variability in airway dimensions and branching
patterns.
December 2009
4-8

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   c
   o
   c
   o
   o
   Q.
               0.04
                       0.06
                 0.08     0.10                1           3

                        Particle Diameter (|im)

                                              * = p < 0.05
                                Male
                                Female
Vt = 500 ml
Q = 250 mUs
                                                 Source: Data from Kim and Hu (1998, 0860661 and Kim and Jaques (2000, 0128111.
Figure 4-5.
Total lung deposition measured in healthy adults (UF, 11 M, 11 F, 31 ± 4 yr; fine
and coarse, 11 M, 11 F, 25 ± 4 yr) during controlled breathing on a mouthpiece.
Deposition calculated from aerosol bolus measurements between 50 and 500 ml
into a breath with 50 ml increments. Illustrated data are means and standard
errors. Asterisk indicates significantly greater total deposition in females versus
males.
4.2.2.2.   Extrathoracic Region

      The first line of defense for protecting the lower respiratory tract from inhaled particles is the
nose and mouth. Particle deposition in the ET region, especially the nasal passages, reduces the
amount available for deposition in the TB and alveolar regions. Recent data have become available,
but are largely derived from computational fluid dynamics (CFD) modeling and experimental
measurements in casts. As most of these studies do not substantially improve our understanding of
deposition in the ET region they are not reviewed here.
      For particles >1 um dae, deposition efficiency in the oral and nasal passages has been generally
described as a function of an impaction  parameter (Stokes number) with the addition of a flow
regime parameter (Reynolds number) for the oral  passages (Finlay and Martin, 2008, 155776; Grgic
et al, 2004,  155810; Kelly et al,  2005,  155894; Schroeter et al., 2006, 156076). For an adult male,
the CFD  simulations of Schroeter et al. (2006, 156076) predicted nasal deposition of 10 um dae
particles  was 90%, and 100% for a VE of 7.5 L/min (rest) and 15 L/min (light activity), respectively.
Thus, relatively few large coarse  particles will pass through the nasal passages into the lungs. Since
the nasal passages are more efficient at removing  inhaled particles than the oral passage, an
individual's  mode of breathing (i.e., oral versus nasal) influences the quantity of particles penetrating
to the lung.
      In  limited studies, it has been shown that children tend to have more oral breathing both at rest
and during exercise and also displayed more variability than adults (Becquemin et al., 1999,  155679;
Bennett et al., 2008, 156269; James et al., 1997, 042422). In contrast to adults, there is little data on
the uptake of particles for oral or nasal breathing in children. Theoretical calculations by Xu and Yu
(1986, 072697) predict enhanced deposition of particles (>2 um) in the head region for children
when compared to adults. Studies of fine particle  deposition in physical models of the nose, scaled to
adult versus  children sizes, predict that deposition efficiency in the nose is a function of pressure
drop across the nose (Phalen et al., 1989, 156023). Consequently, these model analyses suggest that,
when properly scaled physiological flows are used in the calculation of nasal deposition, children,
who have higher nasal resistance than adults, should have higher nasal deposition compared to
adults. Surprisingly, the few studies reporting measures of nasal deposition in children, found lower
nasal deposition efficiencies for fine particles (1-3 um dae) as compared to adults, despite their higher
nasal resistances (Becquemin et al., 1991, 009187; Bennett et al., 2008, 156269). These findings of
lesser nasal versus oral breathing and less efficient nasal deposition suggest that children's lower
respiratory tract (i.e., the TB and  alveolar regions) may receive a higher dose of ambient PM
December 2009
                               4-9

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compared to adults. Normalized to lung surface area, the dose rate to the lower airways of children
versus adults is increased further because children breathe at higher minute ventilations relative to
their lung volumes (see Section 4.2.4.2 on age as a factor modulating deposition).


4.2.2.3.   Tracheobronchial and Alveolar Region

      Inhaled particles passing the ET region enter and may become deposited in the lungs. For any
given particle size, the pattern of particle deposition influences clearance by partitioning deposited
material among lung regions. Deposition in the tracheobronchial airways and alveolar region cannot
be directly measured in vivo. Much of the available deposition data for the TB  and alveolar regions
have been obtained from experiments with radioactively labeled, poorly soluble particles (U.S. EPA,
1996, 079380) or by use of aerosol bolus techniques (U.S. EPA, 2004, 056905). In general, the
ability of these experimental data to define specific sites of particle deposition is limited to
anatomically large regions of the respiratory tract such as the  head, larynx, bronchi, bronchioles, and
alveolar region. Mathematical modeling can provide more refined predictions of deposition sites.
Comparisons of the modeling results obtained with two  publicly available models were provided in
Figure 4-3 and Figure 4-4. Highly localized sites of deposition within the bronchi are described in
Section 4.2.2.4. Both experimental and modeling techniques are based on many assumptions that
may be relatively good for the healthy lung but not for the diseased lung. For discussion of these
issues, the reader is referred to Sections 4.2.4.4 and 4.2.4.5.


4.2.2.4.   Localized Deposition Sites

      From a toxicological perspective, it is important to realize that not all epithelial cells in an
airway will receive the same dose of deposited particles. Localized deposition in the vicinity of
airway bifurcations has been analyzed using experimental and mathematical modeling techniques. In
the 1996 PM AQCD, experimental data were available illustrating the peak deposition of coarse
particles  (3, 5, and 7 um dae) in daughter airways during inspiration and the parent airway during
expiration, but always near the carinal ridge (Kim and Iglesias, 1989, 078539; Kim et al., 1989,
078538). In the 2004 PM AQCD, mathematical models  predicted distinct "hot spots" of deposition
in the vicinity of the carinal ridge for both coarse (10 um) and UF (0.01 um) particles (Heistracher
and Hofmann, 1997, 047514; Hofmann et al., 1996, 047515). In a model of lung generations 4-5
during inspiration, hot spots occurred at the carinal ridge for 10 um dae  particles due to inertial
impaction and for 0.01 um particles  due to secondary flow patterns formed at the bifurcation. During
expiration, preferential sites of deposition for both particle sizes occurred 1) approaching the
juncture of daughter airways on the walls forming and across the lumen from the carinal ridge; and
2) the top and bottom (visualizing the Y-shaped geometry laying horizontal) of the parent airway
downstream of the bifurcation.
      Recent studies further support these findings (Balashazy et al., 2003, 155671; Farkas  and
Balashazy, 2008,  157358; Farkas et al., 2006, 155771; Isaacs  et al., 2006, 155861). Most of these
studies quantified localized deposition in terms of an enhancement factor. Typically, the
enhancement factor is the ratio of the deposition in a pre-specified surface area (e.g., 100 x 100 um
which corresponds to -10 x 10 epithelial cells) to the average deposition density for the whole
airway geometry. These enhancement factors are very sensitive to the size of the surface considered
(Balashazy et al., 1999, 043201). The studies by Farkas  et al.  (2006, 155771) and Farkas and
Balashazy (2008, 157358) investigated the phenomena of localized deposition down to 0.001 um
particles. The deposition of 0.001 um was rather uniform, however,  the deposition pattern became
increasingly less uniform with increasing particle size. These studies indicate that, for particles
greater than -0.01 um, some cells located near the carinal ridge of bronchial bifurcations may
receive hundreds  to thousands times the average dose (particles per unit surface area) of the parent
and daughter airways. Furthermore, the inertial impaction of particles > 1 um dae at the carinal ridge
of large bronchi will increase with increasing inspiratory flows. In a comparison of constricted
versus healthy airways, Farkas et al. (2006, 155771) also reported that the overall deposition
efficiency of 10 um dae particles at bifurcations downstream of a constriction may be increased by
18 times. Given these considerations, Phalen and Oldham (2006, 156024) noted that substantial
doses of particles (> 1 um dae) may be justified for in vitro studies using tracheobronchial epithelial
cell cultures.
December 2009                                  4-10

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4.2.3.  Interspecies Patterns of Deposition

      The primary purpose of this document is to assess the health effects of particles in humans. As
such, human dosimetry studies have been stressed in this chapter. Such studies avoid the
uncertainties associated with the extrapolation of dosimetric data from laboratory animals to humans.
However, animal models have been and continue to be used in evaluating PM health effects because
of ethical considerations regarding the types of studies that can be performed with human subjects.
Thus, there is a considerable need to understand dosimetry in animals and dosimetric differences
between animals and humans. Limited new data are becoming available. Similar deposition
efficiencies have been reported in nasal casts of human and rhesus monkey for 1-10 um dae for
inspiratory flows mimicking resting breathing patterns (Kelly et  al, 2005, 155894). Oldham and
Robinson (2007, 156003) recently provided morphological data  and predicted particle deposition in
an asthma mouse model.
      Interspecies similarities and differences in  deposition were described in detail in the last two
PM AQCDs (U.S. EPA, 1996, 079380; U.S. EPA, 2004, 056905). It was concluded that the general
pattern of total particle deposition efficiency was similar between laboratory animals and humans:
deposition increases on both sides of a minimum that occurs for  particles of 0.2-1 um. There are,
however, marked interspecies differences in uptake into the respiratory tract and regional deposition.
For instance, the nasal inhalability of 10 urn dae particles is predicted to be 96% in humans, whereas
it is only 44% in rats (Menache et al., 1995, 006533). In most laboratory animal species (rat, mouse,
hamster, guinea pig, and dogs), deposition in the  ET region is near 100% for particles >5 um dae
(Raabe et al.,  1988, 001439). indicating greater efficiency than that seen in humans. Detailed
presentation of dosimetric difference between rats and humans are available elsewhere (Brown et al.,
2005, 089308: Jarabek et  al., 2005, 056756).
      Brown et al. (2005, 089308) conducted a thorough evaluation of extrapolations between rats
and humans in relation to PM exposures. One of  many factors they considered was the choice of a
dose metric appropriate for comparison between  species. For example, deposited mass may be an
appropriate PM indicator  for health effects associated with soluble PM constituents. For health
effects associated with insoluble PM, the particle number, surface area, or mass may be appropriate
indicators. Given interspecies differences in deposition patterns and clearance rates, the question of
retained versus deposited  dose was also discussed. It was concluded that for acute  effects, the
incremental dose may  be the appropriate type of  dose metric. For chronic effects, long-term burden
may be more appropriate. For various dose metrics, estimates of particle concentration and exposure
duration required for a rat to receive the same dose as received by a human were obtained with
consideration of activity levels, mode of breathing, and particle size distributions. It was noted that
high PM exposures over the period of months can lead to particle overload in rats (see
Section 4.3.4.4). Exposure regimes were derived  as a function of particle size and exposure duration
that should avoid overwhelming macrophage mediated clearance achieving particle overload in rats
(see Table 12 in Brown et al., 2005, 089308). The dosimetric calculations indicated that to achieve
nominally similar acute doses per surface area in rats, relative to humans undergoing moderate to
high exertion, PM exposure concentrations for rats  would need to be somewhat higher than for
humans.  Since particle clearance from the lungs of rats is faster than humans, much higher exposure
concentrations are required for the rat to simulate retained burdens of humans.  Illustrating the
complexity of such analyses, in some cases, rats were found to require lower exposures  than humans
to have comparable doses (generally when considering a scenario of humans at rest).


4.2.4.  Biological Factors Modulating  Deposition

      Evaluation of factors affecting particle deposition is important to help understand potentially
susceptible subpopulations.  Differences in biological response following pollutant exposure may be
caused by dosimetry differences as well as by differences in innate sensitivity. The effects of
different biological factors on deposition were discussed in the 2004 PM AQCD (U.S. EPA, 2004,
056905) and are summarized briefly here.
December 2009                                 4-11

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4.2.4.1.   Physical Activity
      The activity level of an individual is well recognized to affect their minute ventilation and
route of breathing. Changes in minute ventilation during exercise are accomplished by increasing
both VT and f (Table 4-1). Humans are oronasal breathers tending to breathe through the nose when
at rest and increasingly through the mouth with increasing activity level. There is considerable inter-
individual variability in both the route by which people breathe and the way breathing pattern
changes occur.


Table 4-1.    Breathing  patterns with activity level in adult human male.
Activity
Breaths/min
Tidal volume, mL
Minute ventilation, L/min
Awake
Rest3
12
625
7.5
Slow
Walk3
16
813
13
Light
Exertion
19
1000
19
Moderate
Exertion 3
28
1429
40
Heavy
Exertion
26
1923
50
                                              Sources: 'Winter-Sorkina and Cassee (2002, 043670): bICRP (1994, 006988)


      Individuals typically breathe through their nose while at rest, switching to oronasal breathing
as ventilation increases (Bennett et al., 2003, 191977; Niinimaa et al, 1981, 071758). The role of the
nose in filtering particles is diminished as airflow is diverted from the nose to the mouth during
exercise, bringing more particles to the lower respiratory tract. A recent study in adults (Bennett et
al., 2003, 191977) found that nasal ventilation during exercise varied as a function of both race and
gender. African-Americans possessed a greater nasal contribution to breathing during exercise than
Caucasians. At similar exercise efforts (i.e., normalized to a % maximum work capacity) the females
also had  a greater nasal contribution to breathing during exercise than males.
      In  addition, when individuals increase their ventilation with activity the total number of
particles  inhaled per unit time (i.e., exposure rate) increases, but the fractional deposition of particles
in each breath also changes with breathing pattern. Figure 4-3 and Figure 4-4 illustrate predicted
deposition fractions in the respiratory tract during rest versus light exercise, respectively. During
exercise, both VT and f increase. Fractional deposition for all particles increases with increased VT.
Increasing the f, however, decreases the fractional deposition of fine and UFPs due to decreased time
for gravitational and diffusive deposition. For particles larger than a dae of roughly 3 um, increasing f
can increase the deposition fraction due to increased impaction in the extrathoracic and TB  airways.
Thus, it should be expected that the change in deposition fraction with activity will vary among
individuals depending on the relative influences of these two variables (i.e., VT and f) in a given
subject and the particle size to which they are exposed. Experimentally, the lung deposition fractions
of fine particles during moderate exercise and mouth breathing are unchanged between rest and
exercise  (Bennett et al.,  1985, 190034: Morgan et al., 1984, 190035). Kim (2000, 013112) evaluated
differences in deposition of 1, 3, and 5 um (MMAD) particles under varying breathing patterns
(simulating breathing conditions of sleep, resting, and mild exercise). Total lung deposition increased
with increasing VT at a given flow rate and with increasing flow rate at a given breathing period.
These experimental studies suggest that the total deposited dose rate (i.e., deposition per unit time)
of particles will generally increase in direct proportion to the increase in minute ventilation
associated with exercise.
      The changes in ventilation, i.e., breathing pattern and flow rate, may also  alter the regional
deposition of particles. Coarse particle deposition increases in the TB and  ET regions during exercise
due to the increased flow rates and associated impaction. A rapid-shallow breathing pattern  during
exercise  may result in more bronchial airway versus alveolar deposition, while a slow-deep pattern
will shift deposition to deeper lung regions (Valberg et al., 1982, 190019). Bennett et al. (1985,
190034)  showed for 2.6 urn particles that moderate exercise shifted deposition from the lung
periphery towards ET and larger, bronchial airways.  Similarly, Morgan et al. (1984, 190035) showed
that even for fine particles (0.7  um) TB deposition was enhanced with exercise.  This shift in
deposition toward the bronchial airways results in a much greater dose per unit surface area of tissue
in those regions. Morgan et al. (1984, 190035) also found that the apical-to-basal distribution of fine
December 2009                                   4-12

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particles increased with exercise, i.e., a shift towards increased deposition in the lung apices. This
shift may be less likely for larger particles, however, whose deposition in large airway bifurcations
may preclude their transport to these more apical regions (Bennett et al., 1985, 190034).


4.2.4.2.   Age

      Airway structure and respiratory conditions vary with age, and these variations may alter the
amount and site of particle deposition in the respiratory tract. It was concluded in the 2004 PM
AQCD (U.S. EPA, 2004, 056905) that significant differences between adults and children had been
predicted by mathematical models and observed in experimental studies. Studies generally indicated
that ET and TB deposition was greater in children and that children received greater doses of
particles per lung surface area than adults. Deposition studies in the elderly are still quite limited.
      A few studies have attempted to measure oronasal breathing in children as compared to adults
(Becquemin et al., 1999,  155679; Bennett et al., 2008, 156269; James et al., 1997,  042422). This is
important since particles deposit with greater efficiency in the nose relative to the mouth, thereby
affecting exposure of the lower respiratory tract. James et al. (1997, 042422) found that children (age
7-16 yr, n = 10) displayed more variability than adults with respect to their oronasal pattern of
breathing with exercise. However, it was not possible to predict the pattern of the partitioning of
ventilation during exercise based on age, gender, or nasal  airway resistance. Further, in a limited
number of children (age 8-16 yr, n = 10), Becquemin et al. (1999, 155679) found that the children
tended to display  more oral breathing both at rest and during exercise than the  adults. The highest
oral fractions were also found in the youngest children. None of these studies,  however, was able to
show a relationship between nasal resistance and the relative contribution of nasal  breathing in
children. Bennett et al. (2008, 156269) made preliminary measurements of the relative contributions
of oral versus nasal breathing at rest and during incrementally graded submaximal  exercise on the
cycle ergometer for children (age 6-10 yr, n = 12) and adults (age 18-27 yr, n = 11). There was a
trend for children to have a lesser nasal contribution to breathing at rest and during exercise, but the
differences from adults were not statistically significant.
      Breathing patterns are well recognized to change with increasing age, i.e., VT increase and
respiratory rates decrease (Tabachnik et al., 1981, 157036; Tobin et al., 1983, 156122). Bennett and
Zeman (1998, 076182) measured the deposition fraction of inhaled, fine particles (2 um dae) in
children (age 7-14 yr, n=16) and adults (age 19-35 yr, n=12) as they breathed the aerosol with their
natural, resting  breathing pattern. Among the children, variation in deposition fractions, measured by
photometry at the mouth, was highly dependent on intersubject variation in VT. On the other hand,
they found no difference in deposition fractions between children versus adults for these fine
particles. This finding and the modeling predictions (Hofmann et al., 1989, 006922) are explained in
part by the smaller VT and faster breathing rate of children relative to  adults for natural breathing
conditions. Bennett et al.  (2008, 156269) also recently reported measures of fine particle (1 and 2 um
dae) deposition at ventilation rates typical of light exercise in children  (age 6-10 yr, n=12) and adults
(age 18-27 yr, n=ll) and  showed that, like with resting breathing, deposition fractions were
predicted by breathing pattern and did not differ or tended to be less in children compared to adults.
On the other hand, because children breathe at higher minute ventilations relative to their lung
volumes, the rate  of deposition of fine particles normalized to  lung surface area may be greater in
children versus  adults (Bennett  and Zeman, 1998, 076182).
      Bennett and Zeman (2004, 155686) expanded their  measures of fine particle deposition during
resting breathing to a larger group of healthy children (6-13 yr; 20 boys, 16 girls) and found  again
that the variation in total deposition was best predicted by VT (r = 0.79, p < 0.001). But both VT and
resting minute ventilation increased with both height and body mass index (BMI) of the children.
Interestingly, these data suggest that for a given height and age, children with higher BMI have
larger minute ventilations and VT at rest than those with lower BMI. These differences in breathing
patterns as a function of BMI translated into increased deposition of fine particles in the heaviest
children. The rate of deposition (i.e., particles depositing per unit time) in the overweight children
was 2.8 times that of the leanest children (p < 0.02). Among all children, the rate of deposition was
significantly correlated with BMI (r = 0.46, p < 0.004). Some of the increase in deposition fractions
of heavier children may be due to their elevated VT, which was well correlated with BMI (r = 0.72,
p< 0.001).
      In 62 healthy adults with normal lung function aged 18-80 yr, Bennett et al. (1996, 083284)
showed there was no effect of age on the whole lung deposition fractions of 2-um particles under
December 2009                                  4-13

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natural breathing conditions. Across all subjects, the deposition fractions were found to be
independent of age, depending on breathing period (r = 0.58, p < 0.001) and airway resistance
(r = 0.46, p < 0.001). In the same adults breathing with a fixed pattern (360 mL VT, 3.4 sec breathing
period), there was a mild decrease in deposition with increasing age, which could be attributed to
increased peripheral airspace dimensions in the elderly.


4.2.4.3.   Gender

      Males and females differ in body size, conductive airway size, and ventilatory parameters;
therefore, gender differences in deposition might be expected. In some of the controlled studies,
however, the men and women were constrained to breathe at the same VT and f Since women are
generally smaller than men, the increased minute ventilation of women compared to their normal
ventilation could affect deposition patterns. This may help explain why gender related effects on
deposition have been observed in some studies.
      Kim and Hu (1998, 086066) assessed the regional deposition patterns of 1-, 3-, and 5-um
MMAD particles in healthy adult males and females using controlled breathing. The total fractional
deposition in the lungs was similar for both genders with the 1-um particle size, but was greater in
women for the 3- and 5-um particles. Deposition also appeared to be more localized in the lungs of
females compared to those of males. Kim and Jaques (2000, 012811) measured deposition in healthy
adults using sizes in the UF mode (0.04-0.1  um). Total fractional lung deposition was greater in
females than in males for 0.04- and 0.06-um particles. The region of peak fractional deposition was
shifted closer to the mouth and peak height was slightly greater for women than for men for all
exposure conditions. The total lung deposition data from these studies are illustrated in Figure 4-5.
These differences were generally attributed to the smaller size of the upper airways, particularly of
the laryngeal structure, in females.
      In another study (Bennett et al,  1996, 083284). the total respiratory tract deposition of 2-um
particles was examined in adult males and females aged 18-80 yr who breathed with a normal resting
pattern. There was a tendency for greater deposition fractions in females compared to males.
However, since males had greater minute  ventilation, the deposition rate (i.e., deposition per unit
time) was greater in males than in females. More recently, Bennett and Zeman (2004, 155686) found
no difference in the deposition of 2-um particles in boys versus girls aged 6-13 yr (n = 36).


4.2.4.4.   Anatomical Variability

      Anatomical variability, even in the absence of respiratory disease, can affect deposition
throughout the respiratory tract. The ET region is the first exposed to inhaled particles and, therefore,
deposition within this region would reduce the amount of particles available for deposition in the
lungs. Variations in relative deposition within the ET region will, therefore, propagate through the
rest of the respiratory tract, creating differences in calculated doses among individuals.
      The influence of variations in nasal airway geometry on  particle deposition has been
investigated. Cheng et al. (1996, 047520)  examined nasal airway deposition in healthy adults using
particles ranging in size from 0.004 to 0.15 um and at 2 constant inspiratory flow rates, 167 and
333 mL/s. Inter-individual variability in deposition was correlated with the wide variation of nasal
dimensions; in that, greater surface area, smaller cross-sectional area, and increasing complexity of
airway shape were all associated with enhanced deposition. Bennett and Zeman (2005, 155687) have
also shown that nasal anatomy influences  the efficiency of particle uptake in the noses of adults.  For
light exercise breathing conditions in adults, their study demonstrated that nasal deposition
efficiencies for both 1- and 2-um monodisperse particles were  significantly less in African
Americans versus Caucasians. The lesser nasal efficiencies in African-Americans were associated
with both lower nasal resistance and less elliptical nostrils compared to Caucasians.
      Within the lungs, the branching structure of the airways may also differ between individuals.
Zhao et al. (2009, 157187) recently examined the bronchial anatomy of the left lung in patients
(132 M, 84 W; mean age 47 yr) that underwent conventional thoracic computed tomography scans
for various reasons. At the level of the segmental bronchus in the upper and lower lobes,  a
bifurcation occurred in the majority  of patients. A trifurcation, however, was observed in 23% of the
upper and 18% of the lower lobes. Other more unusual findings were also reported such as four
bronchi arising from the left upper lobe bronchus. As described in Section 4.2.2.4, deposition can be
highly localized near the carinal ridge of bifurcations. The effect of a bifurcation versus other
December 2009                                  4-14

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branching patterns on airflow patterns and particle deposition has not been described in the literature.
Martonen et al. (1994, 000847) showed that a wide blunt carinal ridge shape dramatically affected
the flow stream lines relative to a narrower and more rounded ridge shape. Specifically, there were
high flow velocities across the entire area of the blunt carinal ridge versus a smoother division of the
airstream in the case of the narrow rounded ridge shape. The implication may be that localized
particle deposition on the carinal ridge would increase with ridge width. A similar situation might be
expected for a trifurcation versus a bifurcation. These differences in branching patterns provide a
clear example of anatomical variability among individuals that might affect both air flow patterns
and sites of particle deposition.


4.2.4.5.   Respiratory Tract Disease

      The presence of respiratory tract disease can affect airway structure and ventilatory
parameters, thus altering deposition  compared to that occurring in healthy individuals. The effect of
airway diseases on deposition has been studied extensively, as described in the 1996 and 2004 PM
AQCD (U.S.  EPA, 1996, 079380: U.S. EPA, 2004,  056905). Studies described therein showed that
people with chronic obstructive pulmonary disease  (COPD) had very heterogeneous deposition
patterns and differences in regional deposition compared to healthy individuals. People with
obstructive pulmonary diseases tended to have greater deposition in the TB region than did healthy
people. Furthermore, there tended to be an inverse relationship between bronchoconstriction and the
extent of deposition in the alveolar region, whereas total respiratory tract deposition generally
increased with increasing degrees of airway obstruction.
      The vast majority of deposition studies in individuals with respiratory disease have been
performed during controlled breathing, i.e., all subjects breathed with the same VT and f However,
although resting VT is similar or elevated in people  with COPD compared to healthy individuals, the
former tend to breathe at a faster rate, resulting in higher than normal tidal peak flow and resting
minute ventilation. Thus, given that  breathing patterns differ between healthy and obstructed
individuals, particle deposition data  for controlled breathing may not be appropriate for estimating
respiratory doses from ambient PM exposures.
      Bennett et al. (1997, 078839) measured the fractional deposition of insoluble 2-um particles in
moderate-to-severe COPD patients (n = 13; mean age 62 yr) and healthy older adults (n =  11; mean
age 67 yr) during natural resting breathing. COPD patients had about a 50% greater deposition
fraction and a 50% increase in resting minute ventilation relative to the healthy adults. As a result,
the patients had an average deposition rate of about 2.5 times that of healthy adults. Similar to
previously reviewed studies (U.S. EPA, 1996, 079380: U.S. EPA, 2004, 056905). these investigators
observed an increase in deposition with an increase in airway resistance, suggesting that deposition
increased with the severity of airway disease.
      Brown et al. (2002, 043216) measured the deposition of an UF aerosol (CMD = 0.033 um)
during natural resting breathing in 10 patients with moderate-to-severe COPD (mean age 61 yr) and
9 healthy adults (mean age 53 yr). The COPD group consisted of 7 patients with chronic bronchitis
and 3 patients with emphysema. The total deposition fraction in the bronchitic patients (0.67) was
significantly (p < 0.02) greater than in either the patients with emphysema (0.48) or the healthy
subjects (0.54). Minute ventilation increased with disease severity (healthy, 5.8 L/min; chronic
bronchitic, 6.9 L/min; emphysema, 11 L/min). Relative to the healthy subjects, the average dose rate
was  significantly (p < 0.05) increased by 1.5 times in the COPD patients, whereas the average
deposition fraction only tended to be increased by 1.1 times. These data further demonstrate the need
to consider dose rates (which depend on minute ventilation) rather than just deposition fractions
when evaluating the effect of respiratory disease on particle deposition and dose.
December 2009                                  4-15

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                            0.8
                        .2   0.6
                            0.4
                        Q
                            0.2
                            0.0
                                                           Hygroscopic
                                                           Hydrophobic
                              0.03          0.1            0.4
                                Inhaled particle diameter (|jm)
                                                                  Source:DatafromTu and Knutson (1984, 0728701.
Figure 4-6.    Total deposition of hygroscopic sodium chloride and hydrophobic
              aluminosilicate aerosols during oral breathing (VT= 1.0 L; f = 15 min"1).
4.2.4.6.   Hygroscopicity of Aerosols

      Experimental and modeling studies of hygroscopic aerosol growth and deposition in the lung
were extensively discussed in Section 10.4.3.1 of the 1996 PM AQCD (U.S. EPA, 1996, 079380).
Hygroscopic ambient aerosols include sulfates, nitrates, some organics, and aerosols laden with
sodium or potassium. The high relative humidity in the lungs contributes to rapid growth of
hygroscopic particles and dramatically alters the deposition characteristics of ambient hygroscopic
aerosols relative to nonhygroscopic aerosols. Nonhygroscopic particles in the range of 0.3  um have
minimal intrinsic mobility and low total deposition in the lungs. However, a 0.3 um salt particle
(dry) will grow in vivo to nearly 2 um and deposit to a far greater extent (Anselm et al., 1990,
156217). The hygroscopic growth of particles in the respiratory tract decreases diffusive deposition
and increases aerodynamic deposition as illustrated in Figure 4-6.


4.2.5.  Summary

      Particle deposition in the respiratory tract occurs predominantly by diffusion, impaction, and
sedimentation. Deposition is minimal for particle diameters in the range of 0.1 to 1.0  um, where
particles are small enough to have minimal sedimentation or impaction and sufficiently large so as to
have minimal diffusive deposition. In humans, total respiratory tract deposition approaches 100% for
particles of roughly 0.01 um (physical diameter) due to diffusive deposition and for particles of
around 10 um dae due to the efficiency of sedimentation and impaction.
      The first line of defense for protecting the lower respiratory tract from inhaled particles is the
nose and mouth. Nasal deposition approaches 100% in the average human for 10 um  dae particles.
Experimental studies show lower nasal particle deposition in children than adults. Relative to adults,
children also tend to breathe more through their mouth which is less efficient for removing inhaled
particles than the nose. These findings suggest that the lower respiratory tract of children may
receive a higher dose of ambient PM compared to adults. Since children breathe at higher minute
ventilations relative to their lung volumes, the rate of particle deposition normalized to lung surface
area may be further increased relative to adults.
      People with COPD generally have greater total deposition and more heterogeneous  deposition
patterns compared to healthy individuals. The observed increase in deposition correlates with
increases in airway resistance, suggesting that deposition increases with the severity of airway
disease. COPD  patients also have  an increased resting minute ventilation relative to the healthy
adults. This demonstrates the need to consider dose rates (which depend on minute ventilation)
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rather than just deposition fractions when evaluating the effect of respiratory disease on particle
deposition and dose.
      Modeling studies indicate that, for particles greater than -0.01 um, some cells located near the
carinal ridge of bronchial bifurcations may receive hundreds to thousands times the average dose
(particles per unit surface area) of the parent and daughter airways. The inertial impaction of
particles > 1 um dae at the carinal ridge of large bronchi increases with increasing inspiratory flows.
Airway constriction can further augment the overall deposition efficiency of coarse particles at
downstream bifurcations. These findings suggest that substantial doses of particles (> 1 urn dae) may
be justified for in vitro studies using tracheobronchial epithelial cell cultures.
      Our ability to extrapolate between species has not generally changed since the 2004 PM
AQCD (U.S. EPA, 2004, 056905). However, some considerations related to coarse particles warrant
comment. The inhalability of particles having dae of 2.5, 5, and 10 um is 80, 65, and 44% in rats,
respectively, whereas it remains near 100% for a dae of 10 um in humans. In most laboratory animal
species (rat, mouse, hamster, guinea pig, and dogs), deposition in the extrathoracic region is near
100% for particles greater than 5 um dae. By contrast, in humans nasal deposition approaches 100%
for 10 um dae. Oronasal breathing versus obligate nasal  breathing further contributes to greater
penetration of coarse particles into the lower respiratory tract of humans than rodents.



4.3.  Clearance of Poorly Soluble Particles

      This section discusses the clearance and translocation of poorly soluble particles that have
deposited  in the respiratory tract. The term "clearance" is used here to refer to the processes by
which deposited particles are removed by mucociliary action or phagocytosis from the respiratory
tract. "Translocation" is used here mainly to refer to the movement of free particles across cell
membranes and to extrapulmonary sites. In the literature, translocation may also refer to the extra-
and intracellular dissolution of particles and the subsequent transfer of dissociated material to the
blood through extra- and intracellular fluids and across the various cell membranes and lung tissues.
The clearance and  distribution of soluble particles and soluble constituents of particles are discussed
in Section 4.4.
      A basic overview of biological mechanisms and clearance pathways from various regions of
the respiratory tract are presented in the following sections. Then regional kinetics of particle
clearance  are addressed. Subsequently, an update on interspecies patterns and rates of particle
clearance is provided. The translocation of UFPs is also  discussed. Finally, information on biological
factors that may modulate clearance is presented.


4.3.1.  Clearance Mechanisms and Kinetics

      For any given particle size, the deposition pattern of poorly soluble particles influences
clearance by partitioning deposited material between lung regions. Tracheobronchial clearance of
poorly soluble particles in humans, with some  exceptions, is thought (in general) to be complete
within 24-48 h through the action of the mucociliary escalator. Clearance of poorly soluble particles
from the alveolar region is a much slower process which may  continue from months to years.


4.3.1.1.   Extrathoracic Region

      Particles deposited in either the nasal or  oral passages are cleared by several mechanisms.
Particles depositing in the mouth may generally be assumed to be swallowed or removed by
expectoration. Particles deposited in the posterior portions of the nasal passages are moved via
mucociliary transport towards the nasopharynx and swallowed. Mucus flow in the most anterior
portion of the nasal passages is forward, toward the vestibular region where removal occurs by
sneezing, wiping,  or nose blowing.
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4.3.1.2.   Tracheobronchial Region

      Mucociliary clearance in the TB region has generally been considered to be a rapid process
that is relatively complete by 24-48 h post-inhalation in humans. Mucociliary clearance is frequently
modeled as a series of "escalators" moving material proximally from one generation to the next. As
such, the removal rate of particles from an airway generation increases with increasing tracheal
mucus velocity. Assuming continuity in the amount of mucus between airway generations, mucus
velocities decrease and transit times within an airway generation increase with distal progression.
Although clearance from the TB region is generally rapid, experimental evidence discussed in the
1996 and 2004 PM AQCD (U.S. EPA, 1996, 079380: U.S. EPA, 2004, 056905) showed that a
fraction of material deposited in the TB region is retained much longer.
      The slow-cleared TB fraction (i.e., the fraction of particles deposited in the TB region that are
subject to slow clearance) was thought to increase with decreasing particle size. For instance, Roth et
al. (1993, 156928) showed approximately 93% retention of UFPs (30 nm median diameter) thought
to be deposited in the TB region at 24 h post-inhalation. The slow phase clearance of these UFPs
continued with an estimated half-time (ti/2) of around 40 days. Using a technique to target inhaled
particles (monodisperse 4.2 urn MMAD) to the conducting airways, Moller et al. (2004, 155987)
observed that 49 ± 9% of particles cleared rapidly (ti/2 of 3.0 ±1.6 h), whereas the remaining fraction
cleared considerably slower (ti/2 of 109 ± 78 days). The ICRP (1994, 006988) human respiratory
tract model assumes particles < 2.5 urn (physical diameter) to have a slow-cleared TB fraction of
50%. The slow-cleared fraction assumed by the ICRP (1994, 006988) decreases with increasing
particle  size to <1% for 9 urn particles. Considering the UF data of Roth et al.  (1993, 156928) in
addition to data considered by the ICRP (1994, 006988). Bailey et al. (1995, 190057) estimated a
slow-cleared TB fraction of 75% for UFPs. At that time, they (Bailey et al. 1995) also estimated the
slow-cleared fraction to decrease with increasing particle size to 0% for particles > 6 urn. Recent
experimental evidence from the same group (Smith et al., 2008, 190037) showed no difference in TB
clearance among humans for particles with geometric sizes of 1.2 versus 5  urn, but the same dae (5
urn) so as to deposit similarly in the TB airways. For at least micron-sized particles, these recent
findings do not support the particle size dependence of a slow-cleared TB fraction. As discussed
further below, much of the apparent slow-cleared TB fraction may be accounted for by differences in
deposition patterns, i.e., greater deposition in the alveolar region than expected.
      A portion of the slow cleared fraction from the TB region appears to be associated with small
bronchioles. For large particles (dae = 6.2 urn) inhaled at a very slow rate to theoretically deposit
mainly in small ciliated airways, 50% had cleared by 24 h post-inhalation.  Of the remaining
particles, 20% cleared with ati/2 of 2.0 days and 80% with ati/2 of 50 days (Falk et al., 1997,
086080). Using the same techniques, Svartengren et al. (2005,  157034) also reported the existence of
long-term clearance in humans from the  small airways. It should be noted that the clearance rates for
the slow-cleared TB fraction still exceeds the clearance rate of the alveolar region in humans.
Kreyling et al. (1999, 039175) targeted inhaled particle (dae = 2.2 and 2.5 urn)  deposition to the TB
airways  of adult beagle dogs and subsequently quantified particle retention using scintigraphic and
morphometric analyses. Despite the use of shallow aerosol bolus inhalation to a volumetric lung
depth of less than the anatomic dead space, 2.5-25% of inhaled particles deposited in alveoli. At 24
and 96 h post-inhalation, more than 50% of the retained particles were in alveoli. However, 40% of
particles present at 24 and 96 h were localized to small TB airways of between 0.3  and 1 mm in
diameter. Collectively, these studies suggest that although mucociliary clearance is fast and effective
in healthy large airways, it is less effective and sites of longer retention exist in the smaller TB
airways.
      The underlying sites and mechanisms of long-term TB retention in the smaller airways remain
largely unknown.  Several factors may contribute to the existence or experimental artifact of slow
clearance from the smaller TB airways. Even when inhaled to very  shallow lung volumes, some
particles reach the alveolar region (Kreyling et al., 1999, 039175). Therefore, experiments utilizing
bolus techniques to target inhaled particle deposition to the TB airways may have had some
deposition in the alveolar region. This may occur due to variability  in path  length and the number of
generations to the alveoli (Asgharian et al., 2001,  017025) and/or differences in regional ventilation
(Brown  and Bennett, 2004, 190032). Nonetheless, the experimentally measured clearance rates
measured for the slow cleared TB fraction are faster than that of the alveolar region in both humans
and canines. Thus, although experimental artifacts likely occur, they do not discount the existence of
a slow cleared TB fraction. To some extent, it is possible that the slow cleared TB fraction may be
due to bronchioles that do not have a continuous ciliated epithelium as in the larger bronchi. Neither
December 2009                                  4-18

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path length, ventilation distribution, nor a discontinuous ciliated epithelium explains an apparently
slow cleared TB fraction with decreasing particle size below 0.1 urn. As discussed in Section 4.3.3
on Particle Translocation, UFPs cross cell membranes by mechanisms different from larger (~1 urn)
particles. Based on that body of literature, particles smaller than a micron may enter epithelial cells
resulting in their prolonged retention, particularly in the bronchioles where the residence time is
longer and distances necessary to reach the epithelium are shorter compared to that in the bronchi.


4.3.1.3.   Alveolar Region

      The primary alveolar clearance mechanism is macrophage phagocytosis and migration to
terminal bronchioles where the cells are cleared by the mucociliary escalator. Alveolar macrophages
originate from bone marrow, circulate briefly as monocytes in the blood, and then become
pulmonary interstitial macrophages before migrating to the luminal surfaces. Under normal
conditions, a small fraction of ingested particles may also be cleared through the lymphatic system.
This may occur by transepithelial migration of alveolar macrophage following particle ingestion or
free particle translocation with subsequent uptake by interstitial macrophages. Snipes et al. (1997,
156092) have also demonstrated the importance of neutrophil phagocytosis in clearance of particles
from the alveolar region. Rates of alveolar clearance of poorly soluble particles vary between species
and are briefly discussed in Section 4.3.2. The translocation of particles from their site of deposition
is discussed in Section 4.3.3.
      The efficiency of macrophage phagocytosis is thought to be greatest for particles between 1.5
and 3 urn (Oberdorster, 1988, 006857). The decreased efficiency of alveolar macrophage for
engulfing UFPs increases the time available for these particles to be taken up by epithelial cells and
moved into the interstitium (Ferin et al., 1992, 044401). Consistent with this supposition
(i.e., translocation increases with time), an increase in titanium dioxide (TiO2) particle transport to
lymph nodes has been reported following inhalation of a cytotoxin to macrophages (Greenspan et al.,
1988, 045031). Interestingly, the long-term clearance kinetics of the poorly soluble UF (15-20 nm
CMD) iridium (Ir) particles were found to be similar to the kinetics reported in the literature for
micrometer-sized particles (Semmler et al., 2004, 055641; Semmler-Behnke et al., 2007, 156080).
Semmler-Behnke et al.  (2007, 156080) concluded that UF Ir particles are less phagocytized by
alveolar macrophage than larger particles, but are effectively removed from the airway surface into
the interstitium. Particles are then engulfed by interstitial macrophages which then migrate to the
airway lumen and are removed by mucociliary clearance to the larynx. The major role of
macrophage-mediated clearance was supported by lavage of relatively few free particles versus
predominantly phagocytized particles at time-points of up to 6 mo. It is also possible that some free
particles as well as particle-laden macrophages were carried from interstitial sites via the lymph flow
to bronchial and bronchiolar sites, including bronchial-associated lymphatic tissue, where they were
excreted again into the airway lumen.


4.3.2.  Interspecies  Patterns of Clearance and  Retention

      There are differences between species in both the  rates of particle clearance from the lung and
manner in which particles are retained in the lung. For instance, based on models of mucociliary
clearance from un-diseased airways, >95% of particles deposited in the tracheobronchial airways of
rats are predicted to be cleared by 5 h post deposition, whereas it takes nearly 40 h for comparable
clearance in humans (Hofmann and Asgharian, 2003, 055579). As noted in Section 4.3.1.2,
however, there is considerable evidence that a sizeable fraction of particles deposited at the
bronchiolar level of the ciliated airways in humans (as well as canines) are cleared at a far slower
rate. The slow cleared TB fraction appears to increase with decreasing particle size.
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                  1.00
               
-------
4.3.3.1.   Alveolar Region

      Numerous studies have examined the translocation of UFPs from their site of deposition in the
lung. Traditionally viewed as a relatively inert particle type, UF TiO2 has received the most study. At
the time the 2004 PM AQCD was released, there were conflicting results regarding the rate and
magnitude of UF carbon translocation from the human lung. Since that time, it has become well-
established that the transport of UF carbon particles from the human lung is far slower than that of
soluble materials. However, it has also been shown in animal studies (primarily of rats) that UFPs
cross cell membranes by mechanisms different from larger (~1 um) particles and that a small
fraction of these particles enter capillaries and may distribute systemically. Described in brief below,
details of selected new studies investigating the disposition of poorly soluble particles are provided
in Annex B.
      There has been some contention regarding ability of UF carbon particles to rapidly diffuse
from the lungs into the systemic circulation. Based on their study of 5 healthy volunteers, Nemmar et
al. (2002, 024914) suggested that UF carbon particles (<100 nm) pass rapidly into the systemic
circulation. However, Brown et al. (2002, 043216) found that the majority of UF carbon particles
(CMD, 33 ± 2 nm) were still in the lungs of healthy human adult volunteers (n = 9; aged 40-67 yr)
and COPD patients (n = 10; 45-70 yr) at 24 h post-inhalation. Brown et al.  (2002, 043216) and
Burch (2002,  056754) contended that the findings reported by Nemmar et al. (2002, 024914) were
consistent with soluble pertechnetate clearance, but not insoluble UF carbon particles. Highly
soluble in normal saline, pertechnetate clears rapidly from the lung with a half-time of-10  min and
accumulates most notably in the bladder, stomach, thyroid, and salivary glands. Three recent studies
have confirmed that the majority (>95%) of UF carbon particles deposited in the lungs of human
volunteers are retained at 24 h post-inhalation  (Mills et al., 2006, 088770; Wiebert et al., 2006,
157146; Wiebert et al., 2006, 156154). Wiebert et al. (2006, 157146) modified their aerosol
generation system to reduce leaching of the 99mTc radiolabel from carbon particles. Except for a
small amount of radiotracer leaching from particles (1.0 ± 0.6% of initially deposited activity in
urine by 24 h), these investigators found negligible radiolabel and associated particle clearance from
the lungs by 70 h. The available data show that there is not a rapid or significant amount of UF
carbon particle migration into circulation (Brown et al., 2002, 043216; Burch, 2002, 056754; Mills et
al., 2006, 088770; Moller et al., 2008, 156771: Wiebert et al., 2006, 157146: Wiebert et al., 2006,
156154).
      Although human studies show that the vast majority of UF carbon particles are retained in the
lungs until at least 24 h post-inhalation, both in vitro and in vivo studies support the rapid (< 1 h)
translocation of free UF TiO2 particles across pulmonary cell membranes (Churg et al., 1998,
085815: Ferin et al., 1992, 044401: Geiser et al., 2005, 087362). Peculiar to TiO2 aerosols, there is
evidence that particle aggregates may disassociate once deposited in the lungs. This disassociation
makes inhaled aggregate size the determinant of deposition amount and site, but primary particle size
the determinant of subsequent clearance (Bermudez et al., 2002, 055578: Ferin et al., 1992, 044401:
Takenaka et al., 1986, 046210). Following disaggregation, the UF TiO2 particles are cleared more
slowly and cause a greater inflammatory response (neutrophil influx) than fine TiO2 particles
(Bermudez et al., 2002, 055578: Ferin et al., 1992, 044401:  Oberdorster et al., 1994, 046203:
Oberdorster et al.,  1994, 056285; Oberdorster  et al., 2000, 039014). The differences in inflammatory
effects and possibly lymph burdens between fine and UF TiO2 in many studies appear related to lung
burden in terms of particle surface area and not particle mass or number (Oberdorster, 1996, 039852:
Oberdorster et al.,  1992, 045110: Oberdorster et al., 2000, 039014: Tran et al., 2000, 013071). More
recently, others have noted that particle surface area is not an appropriate metric across all particle
types (Warheit et al., 2006, 088436). Surface characteristics such as roughness can also affect protein
binding and potentially clearance kinetics, with smoother TiO2 surfaces being more hydrophobic
(Sousa et al., 2004, 089866).
      Geiser et al.  (2005, 087362) conducted a detailed examination of the disposition of inhaled UF
TiO2 in 20 healthy adult rats. They found that distributions of particles among lung tissue
compartments appeared to follow the volume fraction of the tissues and did not significantly differ
between 1 and 24 h post-inhalation. Averaging 1- and 24-h data, 79.3 ± 7.6% of particles were on the
luminal  side of the airway surfaces, 4.6 ± 2.6% were in epithelial or endothelial cells, 4.8 ± 4.5%
were in connective tissues, and 11.3 ± 3.9% were within capillaries. Particles within cells were not
membrane bound. It is not clear why the fraction of particles identified in compartments such as the
capillaries did not differ between 1  and 24 h post-inhalation. These findings were consistent with the
smaller study of 5 rats by Kapp et al. (2004, 156624) who reported identifying TiO2 aggregates in a
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type II pneumocyte; a capillary close to the endothelial cells; and within the surface-lining layer
close to the alveolar epithelium immediately following a 1-h exposure. These studies effectively
demonstrate that some inhaled UF TiO2 particles, once deposited on the pulmonary surfaces, can
rapidly (< 1 h) translocate beyond the epithelium and potentially into the  vasculature.
      Extrapulmonary translocation has also been described for poorly soluble UF gold and Ir
particles. In male Wistar-Kyoto rats exposed to UF gold particles (5-8 nm), Takenaka et al. (2006,
156110) reported a low but significant fraction (0.03 to 0.06% of lung concentration) of gold in the
blood from 1 to 7 days post-inhalation. Semmler et al. (2004, 055641) also found small but
detectable amounts of poorly soluble Ir particle (15 and 20 nm CMD) translocation from the lungs of
male Wistar-Kyoto rats to secondary target organs like the liver, spleen, brain, and kidneys. Each of
these organs contained about 0.2% of deposited Ir. The peak levels in these organs were found 7 days
post-inhalation. The translocated particles were largely cleared from extrapulmonary organs by 20
days and Ir levels were near background at 60 days post-inhalation. Particles may have been
distributed systemically  via the gastrointestinal tract. Immediately after the 6-h inhalation exposure,
18 ± 5% of the deposited Ir particles had already cleared into the gastrointestinal tract. After 3 wk,
31 ± 5% of the deposited particles were retained in the lung. By 2 and 6 mo post-inhalation, lung
retention was 17 ± 3 and 7 ± 1%, respectively. The particles appeared to be cleared predominantly
from the peripheral lung via the mucociliary escalator into the GI tract and were found in feces.
      A few recent studies have characterized differences in the behavior of fine and UF particles in
vitro. Geiser et al. (2005, 087362) found that both UF and fine (0.025 (im gold, 0.078  (im TiO2, and
0.2 (im TiO2) particles cross cellular membranes by non-endocytic (i.e., involving vesicle formation)
mechanisms such as adhesive interactions and diffusion, whereas the phagocytosis of larger 1 (im
TiO2 particles is ligand-receptor mediated. Edetsberger et al. (2005, 155759) found that UFPs
(0.020 um polystyrene) translocated into cells by first measurement (~1 min after particle
application). Intracellular agglomerates of 88-117 nm were seen by 15-20 min and of 253-675 nm by
50-60 min after particle  application. These intracellular aggregates were thought to result from
particle incorporation into endosomes or similar structures since Genistein or Cytochalasin treatment
generally blocked aggregate formation. Interestingly, particles did not translocate into dead cells,
rather they attached to the outside of the cell membrane. Amine- or carboxyl-modified surfaces (46
nm polystyrene) did not affect translocation across  cultures  of human bronchial epithelial cells with
about 6% regardless of the surface characteristics (Geys et al., 2006, 155789).


4.3.3.2.   Olfactory  Region

     Numerous studies have demonstrated the translocation of soluble and poorly soluble particles
from the olfactory mucosa via the axons to the olfactory bulb of the brain. The vast majority of these
studies were conducted in rodents. However, DeLorenzo (1970, 156391) observed the rapid (within
30-60 min) movement of 50 nm silver-coated colloidal gold particles instilled on the olfactory
mucosa into the olfactory bulb of squirrel monkeys. The specifics of this  and other key studies that
have investigated the translocation of particles to the olfactory bulb are provided in Annex B.
      Two recent studies reported the movement of UFPs deposited in the olfactory region of the
nose along the olfactory nerve and into the olfactory bulb of the brain in rats. Oberdorster et al.
(2004, 055639) exposed rats to UF carbon particles (36 nm CMD, 1.7 og) containing 13C in a whole-
body chamber for 6 h. The distribution of1 C was followed for 7  days postexposure. There was a
significant increase in 13C in the olfactory bulb on Day 1 with persistent and continued increase
through Day 7. Elder et  al. (2006, 089253) exposed rats to manganese (Mn) oxide (~30 nm
equivalent sphere with 3-8 nm primary particles) via whole-body inhalation exposure for 12 days  (6
h/day,  5 days/wk) with both nares open or Mn oxide for 2 days  (6 h/day)  with right nostril blocked.
After the 12 days exposure via both nostrils, Mn in the olfactory bulb increased 3.5-fold. After the
2-day exposure with the right nostril blocked, Mn was found mainly in the left olfactory bulb (2.4-
fold increase). These studies suggest the neuronal uptake and translocation of UFPs  without particle
dissolution and in the  absence of mucosal injury.
      Elder et al.  (2006, 089253) also addressed the issue of whether solubilization of particles was
requisite for translocation along the olfactory nerve and into the brain. Similar amounts of soluble
manganese chloride (MnCl2) and poorly soluble Mn oxide were instilled  onto the left naris of
anesthetized rats.  At 24 h post-instillation,  similar amounts of Mn were found in the left olfactory
bulb of rats instilled with MnCl2 (8.2 ± 3.6% of instilled) and Mn oxide (8.2 ± 0.7% of instilled). If
solubilization were required for translocation, then a lower amount of Mn oxide than MnCl2 should
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have reached the olfactory bulb. Following 14 consecutive days of aerosol exposure, Dorman et al.
(2001, 055433) demonstrated that more soluble Mn sulfate reaches the olfactory bulb and striatum of
rat brains than the poorly soluble form of Mn tetroxide. Nonetheless, the Mn levels were statistically
increased in both the olfactory bulb and striatum following exposure to Mn tetroxide relative to
filtered air. In a subsequent 13-wk exposure study, Dorman et al. (2004, 155752) also demonstrated
that more soluble manganese sulfate (MnSO4) reached the olfactory bulb than was observed for the
less soluble Mn form (hureaulite). Both the soluble and less soluble forms of Mn resulted in
statistically increased levels of Mn in the olfactory  bulb relative to air exposed controls. The soluble
MnSO4 was also observed to reach the striatum and cerebellum. In addition, Yu et al. (2003, 156171)
demonstrated increased Mn levels in the brains of rats exposed to welding-fumes for 60 days,
however, the role of transport via the blood is less clear in this study.
      The translocation of zinc (Zn) and TiO2 to the olfactory bulb has also been reported in the
literature. Persson et al. (2003, 051846) observed the translocation of Zn to the olfactory bulbs
following instillation in both rats and freshwater pike. Wang et al. (2007, 156146) reported the
translocation of both fine (155 nm) and UF (21 and 71 nm) TiO2 particles in mice. Interestingly, a
qualitative analysis of the data showed that more of the fine TiO2 than UF TiO2 reached the olfactory
bulb. Wang et al. (2007,  156146) suggested that a strong hydrophilic character and propensity for
aggregation reduced the translocation of the UF TiO2.
      The importance of particle translocation to the  brain is not yet understood. Translocation via
the axon to the olfactory bulb has been observed for numerous  compounds of varying composition,
particle size, and solubility. Although the rate of translocation is rapid, perhaps less than an hour, the
magnitude of transport remains poorly characterized. With regard to the magnitude of transport,
Elder et al.  (2006, 089253) found that as much as 8% of both soluble and insoluble forms of Mn
were translocated to the olfactory bulb in rats following intranasal instillation. It is also still unclear
to what extent translocation to the olfactory bulb and other brain regions may vary between species.
The olfactory mucosa covers approximately 50% of the nasal epithelium in rodents versus only
about 5% in primates (Aschner et al., 2005, 155663). Additionally, a greater portion of inhaled air
passes through the olfactory region of rats relative to  primates (Kimbell, 2006, 155902). These
differences may predispose rats, more so than humans, to deposition of particles in the olfactory
region with subsequent particle translocation to the olfactory bulb.


4.3.4.  Factors Modulating Clearance



4.3.4.1.   Age

      It was previously concluded that there appeared to be no clear evidence for any age-related
differences in clearance from the lung or total respiratory tract, either from child to adult, or young
adult to elderly (U.S. EPA, 1996, 079380; U.S. EPA,  2004, 056905). Studies showed either no
change or some slowing in mucus clearance with age after maturity. Although some differences in
alveolar macrophage function were reported between mature and senescent mice, no age-related
decline in macrophage function had been observed in humans. A comprehensive review of the recent
and older literature supports a decrease in mucociliary clearance with increasing age beyond
adulthood in humans and animals. Limited animal data also suggest macrophage-mediated alveolar
clearance may also decrease with age.
      Studies addressing the  effects of age on respiratory tract clearance are provided in Annex B.
Ho et al. (2001, 156549) demonstrated that nasal mucociliary clearance rates were about 40% lower
in old (age >40-90 yr) versus young (age 11-40 yr) men and women. Tracheal mucus velocities in
elderly (or aged) humans and beagle dogs are about 50% that of young adults (Goodman et al., 1978,
071130; Whaley et al., 1987, 156153).  Several human studies have demonstrated decreasing rates of
mucociliary particle clearance from the large and small bronchial airways with increasing age
(Puchelle et al., 1979, 006863; Svartengren et al., 2005, 157034; Vastag et al., 1985, 157088). Linear
fits to the data show that rapid clearance (within 1 h)  from large bronchi and prolonged clearance
(between 1-21 days) from the small bronchioles in  an 80-year-old is only about 50% of that in a
20-year-old (Svartengren et al., 2005, 157034; Vastag et al., 1985,  157088). One study reported that
alveolar particle clearance rates decreased by nearly 40% in old versus young rats (Muhle et al.,
1990, 006853). Another study has reported that older rats have an increased susceptibility to
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pulmonary infection due to altered alveolar macrophage function and slowed bacterial clearance
(Antonini et al., 2001, 156219). Although data are somewhat limited, they consistently show a
depression of clearance throughout the respiratory tract with increasing age from young adulthood in
humans and laboratory animals.


4.3.4.2.   Gender

      Gender was not found to affect clearance rates in prior reviews (U.S. EPA, 1996, 079380;
U.S. EPA, 2004, 056905). Studies not included in those reviews also show that human males and
females have similar nasal mucus clearance rates (Ho et al., 2001, 156549). tracheal mucus
velocities (Yeates et al., 1981, 095391). and large bronchial airway clearance rates (Vastag et al.,
1985. 157088).


4.3.4.3.   Respiratory Tract Disease

      At the time of the last two reviews (U.S. EPA, 1996, 079380: U.S. EPA, 2004, 056905). it was
well recognized that obstructive airways disease may influence both the site of initial deposition and
the rate of mucociliary clearance from the airways. When deposition patterns are matched,
mucociliary clearance rates are reduced in patients with COPD relative to healthy controls. The
effects of acute bacterial/viral infections and cough on mucociliary clearance were briefly
summarized in Section 10.4.2.5 (EPA, 1996, 079380) and Section 6.3.4.4 (EPA, 2004, 056905) of
past reviews. While cough is generally a reaction to some inhaled stimulus, in some cases, especially
respiratory disease, it can also serve to clear the upper bronchial  airways of deposited substances by
dislodging mucus from the airway surface. One of the difficulties in assessing effects on infection on
mucociliary clearance is that spontaneous coughing increases during acute infections. Cough has
been shown to supplement mucociliary  clearance of secretions, especially in patients with
obstructive lung disease and primary  ciliary dyskinesia.
      Using a  bolus technique to target specific lung regions, Moller et al. (2008, 156771) examined
particle clearance from the ciliated airways and alveolar region of healthy subjects, smokers, and
patients with COPD. Airway retention after 1.5 hours was significantly lower in healthy subjects
(89 ± 6%) than smokers (97 ± 3%) or COPD patients (96 ± 6%). At 24 and 48 h, retention remained
significantly higher in COPD patients (86 ± 6% and 82 ± 6%, respectively) than healthy subjects
(75 ± 10% and 70 ± 9%, respectively). However, these findings are confounded by  the more central
pattern of deposition in the healthy subjects than in the smokers and COPD patients. Alveolar
retention of particles was similar between the groups at 48 h post-inhalation.
      The effect of asthma on lung clearance of particles may depend  on disease status. Lay et al.
(2009, 190060) found significantly (p < 0.01) more rapid particle (0.22 (im) mucociliary clearance
over a 2-h period post-inhalation in mild asthmatics than in healthy volunteers. Although the pattern
of deposition tended to be more central  in the asthmatics, there was not a statistically significant
difference from healthy controls. In vivo uptake by airway macrophages in mild asthmatics was also
enhanced relative to healthy volunteers  (p < 0.01). In an ex vivo  study, airway macrophages from
individuals with more severe asthma had impaired phagocytic capacity relative to less severely
affected asthmatics and healthy volunteers (Alexis et al.,  2001, 190013). Lay et al. (2009, 190060)
concluded that enhanced uptake and processing of particulate antigens could contribute to the
pathogenesis and progression of allergic airways disease in asthmatics and may contribute to an
increased risk  of exacerbations with parti culate exposure.
      Chen et  al. (2006,  147267) investigated the effect of endotoxin on the disposition of particles.
Healthy rats and those pretreated with endotoxin (12 h before particle  instillation) were instilled with
UF (56.4 nm) or fine (202 nm) particles. In healthy rats, there were no marked differences in lung
retention or systemic distribution between the UF and fine particles. In healthy animals, UFPs were
primarily retained in lungs (72 ± 10% at 0.5-2 h; 65 ± 1% at 1  day; 62 ± 5% at 5 days). Particles
were also detected in the blood (2 ± 1% at 0.5-2 h; 0.1  ± 0.1% at 5 days) and liver (3 ± 2% at 0.5-2
h; 1 ± 0.1% at  5 days) of the healthy animals. At 1 day post-instillation, about 13%  of the  particles
were excreted  in the urine or feces of the healthy animals. In rats pretreated with endotoxin, by  2 h
post-instillation, the UFPs accessed the blood (5 versus 2%) and liver  (11  versus 4%) to a
significantly greater extent than fine particles. The endotoxin-treated rats also had significantly
greater amounts of UFPs in the blood (5% versus 2%) and liver (11%  versus 3%) relative to the
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healthy control rats. This study demonstrates that acute pulmonary inflammation caused by
endotoxin increases the migration of UFPs into systemic circulation.
      Adamson and Preditis (1995, 189982) investigated the possibility that particle deposition into
an already injured lung might affect particle retention and enhance the toxicity of "inert" particles.
Bleomycin was instilled into mice to induce epithelial necrosis and subsequent pulmonary fibrosis.
Instilled 3 days following bleomycin treatment, while epithelial permeability was compromised,
carbon black particles in treated mice were translocated to the interstitium and showed increased
pulmonary retention relative to untreated mice. When instilled 4 wk post-bleomycin treatment, after
epithelial integrity was restored, carbon black particle retention was similar between treated and
untreated mice with minimal translocation to the interstitium. The instillation  of carbon particles did
not appear to increase lung injury in the bleomycin treated mice at either time point. This study
shows that integrity of the epithelium affects particle retention and translocation into interstitial
tissues.


4.3.4.4.   Particle Overload

      Unlike other laboratory animals, rats appear susceptible to "particle overload" effects  due to
impaired macrophage-mediated alveolar clearance. Numerous reviews have discussed this
phenomenon and the difficulties it poses for the extrapolation of chronic effects in rats to humans
(International, 2000, 002892; Miller, 2000, 011822; Morrow, 1994, 006850; Oberdorster, 1995,
046596; Oberdorster, 2002, 021111). Large mammals have slow pulmonary particle clearance and
retain particles in interstitial tissues under normal conditions, whereas rats have rapid pulmonary
clearance and retain particles in alveolar macrophages (Snipes, 1996, 076041). With chronic high
doses of PM there is a shift in the pattern of dust accumulation and response from that observed at
lower doses in rat lungs (Snipes, 1996, 076041; Vincent  and Donaldson,  1990, 002462). Rats
chronically exposed to high concentrations of insoluble particles experience a reduction in their
alveolar clearance rates and an  accumulation of interstitial particle burden (Bermudez et al, 2002,
055578; Bermudez et al.,  2004, 056707; Ferin et al., 1992, 044401; Oberdorster et al., 1994, 046203;
Oberdorster et al., 1994, 056285; Warheit et al., 1997, 086055). With continued exposure, some rats
eventually develop pulmonary fibrosis and both benign and malignant tumors(Lee et al., 1985,
067628; Lee et al.,  1986, 067629; Warheit et al., 1997, 086055). Oberdorster (1996, 039852; 2002,
021111) proposed that high-dose effects observed in rats may be associated with two thresholds. The
first threshold is the pulmonary dose that results in a reduction in macrophage-mediated clearance.
The second threshold, occurring at a higher dose than the first, is the dose at which antioxidant
defenses are overwhelmed and  pulmonary tumors  develop. Intrapulmonary tumors  following TiO2
exposures are exclusive to rats  and are not found in mice or hamsters (Mauderly, 1997, 084631).
Moreover, Lee et al. (1985, 067628)  noted that the squamous cell carcinomas  observed with
prolonged high concentration TiO2 exposures developed from the alveolar lining cells adjacent to the
alveolar ducts, whereas squamous cell  carcinomas in humans which are generally linked with
cigarette smoking are thought to arise from basal cells of the bronchial epithelium.  Quoting  Lee et al.
(1986, 067629). "Since the lung tumors were a unique type of experimentally induced tumor under
exaggerated exposure conditions and have not usually been seen in man or animals, their relevance
to man in questionable."
4.3.5.  Summary
      For any given particle size, the pattern of poorly soluble particle deposition influences
clearance by partitioning deposited material between regions of the respiratory tract. Particles
depositing in the mouth may generally be assumed to be swallowed or removed by expectoration.
Particles deposited in the posterior portions of the nasal passages or the TB airways are moved via
mucociliary transport towards the nasopharynx and swallowed. Although clearance from the TB
region is generally rapid, there appears to be fraction of material deposited in the TB region of
humans that is retained much longer. The underlying sites and mechanisms of long-term TB
retention are not known. The primary alveolar clearance mechanism is macrophage phagocytosis and
migration to terminal bronchioles where the cells are cleared by the mucociliary escalator. Clearance
from both the TB and alveolar region is more rapid in rodents than humans. Mucociliary and
macrophage-mediated clearance decreases with age beyond adulthood.
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      Human data show that there is not a rapid or significant amount of UF carbon particle
migration into circulation. However, both in vitro and in vivo animal studies support the rapid
(< 1 h) translocation of free UF TiO2 particles across pulmonary cell membranes. Extrapulmonary
translocation has also been described in rats for poorly soluble UF gold and Ir particles. A low, but
statistically significant, fraction (0.03-0.06% of lung concentration) of UF gold particles has been
observed in the blood of rats from 1 to 7 days post-inhalation. The translocation in detectable
amounts (<1% of deposited material) of poorly soluble Ir particles (15 and 20 nm CMD) from the
lungs of rats to secondary target organs like the liver, spleen, brain, and kidneys has also been
reported. However, the systemic distribution of particles may have  occurred via normal clearance
from the lungs to the gastrointestinal tract.
      Although the importance of particle translocation to the brain is not yet understood,
translocation from the olfactory mucosa via the axon to the olfactory bulb has been reported in
primates, rodents, and freshwater pike  for numerous compounds of varying composition, particle
size, and solubility. The rate of translocation is rapid, perhaps less than an hour. In rats, as much as
8% of material may become translocated to the olfactory bulb following intranasal instillation. It is
unclear to what extent translocation to  the olfactory bulb and other  brain regions may vary between
species. Interspecies differences may predispose rats, more so than  humans, to the deposition of
particles in the olfactory region with subsequent translocation to the olfactory bulb.



4.4.  Clearance of Soluble  Materials

      Soluble particles and soluble constituents of particles may be absorbed through the epithelium
and distributed systemically or retained in the lung. The rate of dissolution depends on a number of
factors, including particle surface area and  chemical structure.  Some dissolved materials bind to
proteins or other components in the airway surface liquid layer. In the ciliated airways, solutes are
cleared by mucociliary transport and diffuse into underlying tissues and the blood. In the alveolar
regions, the thin barrier between the air and blood allows for rapid transport of solutes into the blood.
The movement of soluble materials depends on the site of deposition in the lung, the rate of material
dissolution from particles, and the molecular weight of the solute. The rate of soluble material
clearance from the lungs depends on epithelial permeability which  may be affected by age,
respiratory disease, and concurrent exposures. While enhanced clearance of insoluble particles acts
to reduce dose to airway tissue, increased transport of soluble matter into the blood stream may
enhance effects on extra-pulmonary organs.


4.4.1.  Clearance  Mechanisms and Kinetics

      The rate of absorption across the epithelium for materials that dissolve in the airway or
alveolar lining fluid is fairly rapid (minutes to hours) and is a function of their molecular size and
their water or lipid solubility (Enna and Schanker, 1972, 155767; Huchon et al, 1987, 024923;
Oberdorster, 1988, 006857; Schanker et al., 1986, 005100). Huchon et al.  (1987, 024923) studied the
clearance of a variety of aerosolized solutes from the lungs of dogs. Solute clearance was inversely
related to molecular weight. Negligible clearance of the largest molecular weight solute (transferrin
mol wt -76,000 daltons) in their study  was found over a 30-min observation period. At the other
extreme, free pertechnetate (mol wt -163 daltons) had a clearance rate of 6% per min. Clearance of
hydrophilic solutes is diffusion limited by pore sizes associated with intercellular tight junctions
(estimated at 0.6-1.5 nm). Absorption of lipophilic compounds that pass easily through cell
membranes is perfusion limited and thus generally occurs  very rapidly. However, if lipophilic
materials are adsorbed onto insoluble particles their retention in the lung may  be prolonged (Creasia
et al., 1976, 059713). In addition to diffusion through intercellular junctions, transcellular transport
of large solutes by pinocytosis into epithelial cells has also been observed (Chinard, 1980, 156341).
      A portion of poorly soluble particles  may become dissolved with subsequent solute clearance.
More rapid dissolution of poorly soluble nano- or UF particles relative to micro-sized particles
occurs due to an increasing surface-to-volume ratio with decreasing particle size. Kreyling et al.
(2002, 037332) examined the dissolution of poorly soluble UF Ir particle agglomerates (15-80 nm
CMD) composed  of 5 nm primary particles. After 7 days, <1% of the particles were dissolved in
buffered saline, whereas 6% dissolved in 1  N hydrochloric acid after 1 day. Thus, the high surface-
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to-volume ratio of UFPs should not be misconstrued to imply rapid dissolution of poorly soluble
particles following deposition in the respiratory tract. However, poorly soluble particles that become
phagocytosed may slowly dissolve in the acidic (pH of 4.3-5.3) environment of the phagolysosome
to be released in their solubilized form from the cell and potential move across the epithelium into
the bloodstream. The dissolution rate is inversely related to particle size and directly related to
specific surface area (Kreyling and Scheuch, 2000, 056281) and facilitated by the acidic
environment of the macrophage (Kreyling, 1992, 067243).
      There is considerable evidence that soluble particles depositing in the bronchial airways are
cleared by dual mechanisms (Bennett and Ilowite, 1989, 000835; Lay et al., 2003, 155920; Matsui
et al., 1998, 040405; Sakagami et al., 2002, 156936; Wagner  and Foster, 2001, 156143). The relative
contribution of their removal by transepithelial absorption versus mucociliary clearance is likely a
function of both the molecular size and water or lipid solubility of the material (Enna and Schanker,
1972, 155767; Huchon et al., 1987, 024923; Oberdorster, 1988, 006857; Sakagami et al., 2002,
156936). Furthermore, the rate of mucociliary transport for soluble particles may be less than that of
insoluble particles (Lay et al., 2003,  155920). Consequently, non-permeating hydrophilic solutes
may remain in contact with the airway epithelium for a longer period than insoluble particles. This
may be due to diffusion of a greater portion of the solute into the periciliary sol layer which may be
transported less efficiently than the mucus layer during mucociliary clearance.  Bronchial blood flow
has also been shown to modulate airway retention of soluble particles (Wagner and Foster, 2001,
156143). i.e., decreasing blood flow increases airway retention of soluble particles.
      As an example of how transport of soluble components of PM may clear the lung by
transepithelial absorption, Wallenborn et al. (2007, 156144) measured elemental content of lungs,
plasma, heart,  and liver of healthy male WKY rats (12-15 wk old) 4 or 24 h following a single
intratracheal (IT)  instillation of saline or 8.33 mg/kg of oil combustion PM containing a variety of
transition metals with differing water and acid solubility. Metals with high water solubility and
relatively high concentration in oil combustion PM  were increased in extrapulmonary organs.
Elements with low water or acid solubility, like silicon and  aluminum, were not detected in
extrapulmonary tissues despite decreased levels in the lung suggesting they cleared the lung
primarily by mucociliary clearance. Thus, PM-associated metals deposited in the lung may be
released into systemic circulation at different rates depending on their water/acid solubility.
      The amount and type of water soluble or leachable metals associated with PM varies with
location and by source. Furthermore some metals such as Zn, Cu, and Fe are essential to body
function while others such as vanadium and nickel are nonessential metals. Consequently the body
and the lung have different ways of dealing with excesses in inhaled soluble metals associated with
PM. Bioavailability, and potentially the toxicity, of leachable metals may be altered by protein
binding within the lung and blood as well as the affinities of these binding sites. For  example Zn is
tightly regulated by a variety of metal binding proteins, including metallothionein and a family of Zn
specific transporters. In the plasma, Zn binds to many proteins, including a2-macroglobulin and
albumin. Zn is an example of a common abundant water soluble metal in ambient air that may
contribute to increased respiratory and cardiovascular disease risk associated with PM exposure.
Wallenborn et al.  (2009, 191172) recently showed that soluble Zn sulfate (in the form of °Zn,  a rare
isotope of Zn) introduced into the lungs by instillation not only reaches, but accumulates in
extrapulmonary organs, including the heart and liver, following pulmonary exposure. However, the
retention of greater than 50% of  Zn in the lung at 4 h post-instillation suggested that the
transepithelial absorption of soluble Zn was indeed  slowed  by binding to proteins in the lungs. While
it could not be ascertained if 70Zn measured in the heart was replacing endogenous Zn pools, any
accumulation in cardiac Zn levels could lead to mitochondrial dysfunction and ion channel
disruption, possibly explaining adverse cardiac effects from inhalation of Zn-rich PM. Effects of Zn
instillation on  epithelial integrity were not evaluated.
4.4.2.  Factors Modulating Clearance
      A number of studies have evaluated the epith
99mTc-diethylenetriaminepentaacetic acid (99mTc-Dl
0.57 nm). These studies are the basis for much of the discussion in this section.
      A number of studies have evaluated the epithelial permeability by measuring the clearance of
99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA), a small hydrophilic solute (492 daltons,
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4.4.2.1.   Age

      In humans, the clearance of water-soluble particles (99mTc-DTPA) from the alveolar epithelium
generally slows with increasing age (Braga et al., 1996, 156289; Pigorini et al., 1988, 156027).
However, Tankersley et al. (2003, 096363) recently showed enhanced permeability of soluble
particles (99mTc-DTPA) in terminally senescent mice just before death, suggesting that a
disintegration of the epithelial barrier may be a feature of lung homeostatic loss during this period of
terminal senescence.


4.4.2.2.   Physical Activity

      The transepithelial transport rates of soluble particles, 99mTc-DTPA, have also been found to
increase during exercise (Hanel et al., 2003, 155826; Lorino et al., 1989, 155946; Meignan et al.,
1986, 156752). This enhancement was  linked to increases in VT associated with exercise (Lorino et
al., 1989, 155946). Regionally, this effect was dominated by increased apical lung clearance and
attributed to an increase in apical blood flow (Meignan et al., 1986, 156752). The increased
permeability with exercise appears to resolve to baseline after a short period post exercise, i.e.,
within a couple hours (Hanel et al., 2003, 155826).


4.4.2.3.   Disease

      Because the integrity of the epithelial surface lining of the lungs may be damaged from lung
disease, particles (either insoluble or soluble) may gain greater access to the interstitium, lymph, and
blood stream. Damage to the epithelial barrier is most likely to acutely affect transepithelial transport
rates of soluble particles. From bronchial biopsies, Laitinen et al. (1985, 037521) found various
degrees of epithelial damage, from loosening of tight junctions to complete denudation of the airway
epithelium, in asthmatics. Consistent with these findings, Ilowite et al. (1989, 156584) found that
asthmatics had increased permeability of the bronchial mucosa to the hydrophilic solute
99mTc-DTPA. On the other hand, a more recent study in a sheep model showed that the presence of
bronchial edema could slow the uptake of soluble DTPA into the blood and enhanced retention in the
airways, likely within the expanded interstitial barrier (Foster and Wagner, 2001, 155778). Both a
leaky epithelial barrier and expanded interstitial barrier associated with asthma may result in
enhanced exposure of submucosal immune and smooth muscle cells to xenobiotic substances.
      Alveolar epithelial permeability was also shown to be affected by the presence of lung
inflammation. The most common finding has been a clear increase in alveolar permeability induced
by cigarette smoking (Jones et al., 1980, 155883). This effect appears to be dependent on the  recent
cigarette smoke exposure as indexed by carboxyhaemoglobin (Jones et al., 1983, 155884) and is
rapidly reversible within a week of smoking cessation  (Mason et al., 1983, 013169). In fact, Huchon
et al. (1984, 156576) demonstrated that COPD patients who have stopped smoking have normal
clearance of 9ymTc-DTPA.
      In general, increased alveolar permeability to 99mTc-DTPA has been found to be associated
with any lung syndrome characterized by pulmonary edema. While the trans-alveolar transport of a
small solute like DTPA is very sensitive to even mild acute lung  injury (such as that associated with
even mild cigarette smoking), increased transport rates of larger molecules (>100K daltons) across
the alveolar epithelium require more severe damage like that seen in adult respiratory distress
syndrome (ARDS) (Braude et al., 1986, 155701; Peterson et al.,  1989, 024922). Interstitial lung
disease and pulmonary fibrosis are also characterized by increased alveolar permeability (Antoniou
et al., 2006, 156220; Bodolay et al., 2005, 156280; Watanabe et al., 2007, 157115). Interestingly,
these recent studies have also shown that the increased permeability in these patients could be
corrected with immunosuppressive/steroid treatments (Bodolay et al., 2005,  156280; Watanabe et al.,
2007, 157115). Furthermore, studies of DTPA clearance in bleomycin injured dogs, a model of
pulmonary fibrosis, suggest that the enhanced permeability is associated with the initial acute phase
of the lung damage, with clearance rates returning to normal as chronic fibrosis developed over time
(Sugaetal., 2003,157024).
      Finally, as evidence of lung complications associated with non-insulin dependent diabetes
(type 2), Lin et al. (2002, 155932) found impairment of alveolar integrity as  shown by increased
transport rates  of both hydrophilic and lipophilic solutes from the lungs  in these patients. By
contrast, a number of other studies have found epithelial permeability reduced, i.e., slower transport
December 2009                                 4-28

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rates, in diabetes (Caner et al., 1994, 156320; Mousa et al, 2000, 156786; Ozsahin et al., 2006,
156833)  that may be related to disease duration and metabolic control (Ozsahin et al., 2006,
156833) . These findings are consistent with thickening of alveolar basement membrane detected in
autopsies of diabetes patients (Weynand et al., 1999,  157140).


4.4.2.4.   Concurrent Exposures

     The integrity of the alveolar epithelium may be disrupted by co-pollutants such that soluble
components of inhaled particles can more easily enter the interstitium and blood stream. Like active
cigarette smoking discussed previously, Beadsmoore et al. (2007, 156259) showed clearance half-
times in healthy passive smokers to be shorter compared with healthy non-smokers but still longer
than in healthy smokers. These findings show a progressive increase in epithelial permeability with
exposure to cigarette smoke. Similarly, acute exposure of humans to 0.4 ppm ozone for 2 h with
intermittent exercise has been shown to alter epithelial integrity and increase clearance of soluble
hydrophilic particles from the alveolar surfaces of the lung (Kehrl et al., 1987, 040824). This effect
persists to at least 24 h post-exposure even following lower exposure levels (0.24 ppm average for
130 min) of ozone (Foster  and Stetkiewicz,  1996, 079920). Similarly,  0.8 ppm O3 exposure for 2 h
in rats caused increased permeability to macromolecules at all levels of the respiratory tract (Bhalla
et al., 1986, 040407) that persisted in the alveolar region beyond 24 h post-exposure. Cohen et al.
(1997,  009213) may have best illustrated the competing effects of mucociliary and trans epithelial
transport by showing that coexposure to ozone affected the retention of inhaled chromium in rats
differently depending on its solubility. In its soluble potassium  chromate form, ozone decreased the
retention of chromium, but when chromium was inhaled as insoluble barium chromate, its retention
in the lung was increased by ozone coexposure. Similarly, a study that showed decreased clearance
of insoluble cesium oxide particles following influenza infection also showed a virus-induced
enhancement of clearance for a soluble cesium chloride (Lundgren et al., 1978, 155950). Chang et
al. (2005, 097776) also recently showed that UF carbon black acts through a reactive oxygen species
(ROS)  dependent pathway to increase epithelial permeability in mice.
     Chronic exposure to other particulate or gaseous pollutants does not always led to increased
epithelial permeability.  Studying subjects with a variety of occupational exposures, Kaya et al.
(2006,  156632) showed that nonsmoking welders  actually have decreased epithelial permeability
relative to nonsmoking control subjects, and occupational exposure of painters to isocyanates has no
effect on bronchoalveolar epithelial permeability (Kaya et al., 2003,  156631).


4.4.3.  Summary

     The healthy airway and alveolar epithelium is generally impermeable to very large insoluble
macromolecules and particles. Water and acid soluble particles may more rapidly move through the
epithelium as they dissolve on the airway surface  or within the  phagolysomes of macrophages.  The
presence of airway inflammation in a variety of airway diseases (e.g., asthma, fibrosis, ARDS,
pulmonary edema, inflammation from smoking) alters epithelial integrity to  allow more rapid
movement of these solutes into the bloodstream. While diabetics are another group recently shown to
have increased susceptibility to particulate air pollution (Zanobetti and Schwartz, 2002, 034821). it
is unclear whether transport of soluble particles across the epithelium is affected in these patients. In
general, it appears that coexposure to irritant pollutants results in a disruption of epithelial integrity
and macrophage function which, on the one hand, retards mucociliary  and alveolar clearance, but
also allows for a more rapid movement of soluble constituents across the epithelial surface into the
interstitium and blood stream. Alterations in epithelial permeability by disease, pollutant exposure,
or infection may partially explain increased susceptibility to PM associated with these co-conditions.
December 2009                                  4-29

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             Chapter 5.  Possible  Pathways/
                           Modes  of Action
     The mechanisms underlying pulmonary effects of inhaled PM have been well-studied in the
laboratory and there is general agreement regarding the key roles played by cellular injury and
inflammation. These pathways are initiated following the deposition of inhaled particles on
respiratory tract surfaces. Since most of these studies were conducted at concentrations of PM much
higher than ambient levels, there is some question regarding the relevance of these responses and
mechanisms to ambient exposures.
     Interestingly, inhaled PM may also affect the cardiovascular, hematopoietic and other systems.
Mechanisms underlying these extra-pulmonary effects are incompletely understood. However,
pulmonary inflammation can lead to systemic inflammation and pulmonary reflexes can activate the
autonomic nervous system (ANS). These latter responses may mediate cardiovascular and other
systemic effects, as will be discussed below. In addition, it has been proposed that PM or soluble
components of PM reach the circulation by translocating across the epithelial and endothelial
barriers  of the respiratory tract. In this way, PM or its components may interact directly with cells in
the vasculature and blood and be transported to the heart and other organs. At this time, evidence
clearly supports the translocation of small solutes following inhalation exposures and the
translocation of soluble components of PM following some high dose exposures involving
intratracheal (IT) instillation. However, there is insufficient evidence to support translocation of
appreciable amounts of intact particles following inhalation exposures at lower concentrations
(Section 4.3.3.1). Future studies will be required to resolve these issues.
     The following sections discuss biological pathways which comprise proposed modes of action
for the pulmonary and extra-pulmonary effects of inhaled PM. Overall themes are emphasized and
supportive evidence from new in vitro and in vivo animal studies is cited. The characterization of
evidence here is for PM in general, since most of the potential pathways or modes of action do not
appear to be specific to a particular size class of PM. However, characteristics of ultrafine particles
(UFPs) may allow for unique modes of action or effects disproportionate to their mass, as will be
described below. Recent studies suggest an enhanced potential of this size class of PM to cause
adverse  effects; however evidence supporting this hypothesis is limited. Finally, a compilation of
results from new inhalation studies which are relevant to ambient PM exposures and which confirm
and extend these proposed mechanisms is found at the end of this chapter. Detailed descriptions of
these key new studies are found in Chapters 6 and 7.
5.1.  Pulmonary  Effects
5.1.1.  Reactive Oxygen Species
     A great deal of research interest has focused on the role of reactive oxygen species (ROS) in
the initiation of pulmonary injury and inflammation following exposure to PM. Numerous studies
have demonstrated PM oxidative potential in in vitro and in vivo assay systems (Ayres et al., 2008,
155666: Cho et al., 2005, 087937: Shi et al., 2003, 088248: Tao et al., 2003, 156111). Both redox
active surface components, such as metals and organic species, and the surface characteristics of
crystal structures have been shown to contribute to oxidative potential (Jiang et al., 2008, 156609:
Tao et al., 2003, 156111: Warheit et al., 2007, 090482). In this way, PM may be a direct  source of
ROS in the respiratory tract (Figure 5-1).
 Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
 Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
 developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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               Redox Active
           Surface Components
             Metals, Organics
       Surface Characteristics
        of Crystal Structures
                                  PM Oxidative
                                     Potential
                                Cell-free assay or
                            oxidation of components
                               in a cellular system
Figure 5-1.    PM oxidative potential.

      PM may also act as an indirect source of ROS in the respiratory tract by stimulating cells to
produce ROS (Ayres et al, 2008, 155666: Tao et al., 2003, 156111) (Figure 5-2). This may explain
the observation that the oxidative potential of isolated PM does not always correlate with cellular or
tissue oxidative stress induced by PM exposure.  Exposure to PM increases intracellular production
of ROS by a variety of mechanisms. For example, PM interaction with cell surfaces results in
stimulation of NADPH oxidase in macrophages  (i.e., the respiratory burst) (Dostert et al., 2008,
155753) and in epithelial cells (Amara et al., 2007, 156212; Becher et al., 2007, 097125; Tamaoki et
al., 2004, 157040). Absorption of PM soluble components (e.g., PAH, transition metals) by
respiratory tract cells can occur (Penn et al., 2005, 088257) and be followed by microsomal
transformation of PAHs to quinones or by redox cycling of transition metals with production of
intracellular ROS (Molinelli et al., 2002, 035347; Xia et al., 2004, 087486).  Disruption of
intracellular iron homeostasis with the subsequent generation of ROS has also been demonstrated
following PM exposure (Ohio and Cohen, 2005, 088272). In some cases, mitochondria serve as the
source of ROS in response to PM (Huang et al., 2003, 156573; Risom and Loft, 2005, 089070;
Soberanes et al., 2006, 156991; Soberanes et al., 2009, 190483). Furthermore, PM interaction with
cells can lead to the induction of nitric oxide synthase (Becher et al., 2007, 097125; Lindbom et al.,
2007, 155934; Xiao et al., 2005, 156164; Zhao et al., 2006, 100996) and the production of nitric
oxide and other reactive nitrogen species (RNS).
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            Iron Sequestration
             Redox Cycling
         Altered iron homeostasis
NADPH
Oxidase


rf-

Binding to Cell Surfaces
Phagocytosis
Cytoskeletal Interactions
          Mitochondria!
        Electron Transport
           Nitric Oxide
            Synthase
                                Cellular Sources
                                   ofROS/RNS
                 Soluble metals
                  Microsomal
                  Metabolism
                (PAH/Quinones)
                                 ROS/RNS Assay
                        Oxidation of Cellular Components
                         Lipid Peroxidation, Nitrotyrosine
                                  HO-1 Induction
Figure 5-2     PM stimulates pulmonary cells to produce ROS/RNS.

      Although all size fractions of PM may contribute to oxidative and nitrosative stress, UFPs may
contribute disproportionately to their mass due to their large surface/volume ratio. The relative
enrichment ofredox active surface components, such as metals and organics, per unit mass may
translate to  a relatively greater oxidative potential of UFPs compared with larger particles with
similar surface components. In addition, the greater surface per unit volume could potentially deliver
relatively more adsorbed soluble components to cells. These components may undergo intracellular
redox cycling following cellular uptake. Furthermore, per unit mass, UFPs may have more
opportunity to interact with cell surfaces due to their greater surface area and their greater particle
number compared with larger PM. These interactions with cell surfaces can lead to ROS generation,
as described above. Recent studies have also demonstrated that UFPs have the capacity to cross
cellular membranes by non-endocytotic mechanisms involving adhesive interactions and diffusion
(Geiser et al., 2005, 087362).  as described in Chapter 4. This may allow UFPs to interact with or
penetrate intracellular organelles.
      In general, high levels of intracellular ROS/RNS can lead to irreversible protein modifications,
loss of cellular membrane integrity, DNA damage and cellular toxicity. Lower levels of ROS/RNS
may cause reversible protein modifications that trigger intracellular signaling pathways and/or
adaptive responses. Thus PM-dependent generation of ROS may be responsible for a continuum of
responses from cell signaling to cellular injury.


5.1.2.  Activation  of Cell Signaling Pathways

      Activation of cell  signaling pathways by ROS/RNS has received increasing attention by
numerous investigators over the years. An early example was provided by Kaul and Forman (1996,
155892) who demonstrated that respiratory burst-derived H2O2 activates the transcription factor
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nuclear factor kappa-light-chain-enhancer of activated B cells (NF-KB). Numerous studies since then
have demonstrated that PM, which serves as both a direct and indirect source of ROS/RNS, activates
cell signaling pathways by this mechanism.
      PM also has the potential to activate cell signaling by mechanisms that are independent of
ROS/RNS. For example, PM delivers water-soluble components, such as endotoxin and zinc (Zn), to
cell surfaces. Endotoxin binds to toll-like receptors on alveolar macrophages and other cells,
resulting in the upregulation of cytokines (Becker et al., 2002, 052419). Zn, a transition metal which
does not redox cycle, inhibits protein tyrosine phophatases in airway epithelial cells resulting in a
cascade of cell signaling events (Tal et al., 2006, 108588). Similarly, PM-mediated delivery of lipid
soluble components  such as PAH results in binding and activation of the arylhydrocarbon receptor
(AhR). AhR is a transcription factor responsible for the upregulation of CYP1A1, a cytochrome
oxidase involved in PAH biotransformation to metabolites capable of forming DNA adducts or
eliciting oxidative stress  responses (Rouse et al., 2008, 156930). In addition, interaction of PM with
cell surfaces may activate cell signaling by perturbation of the cytoskeleton, adherence,
internalization, or receptor-mediated pathways.
      Recent studies involving PM exposures have focused on intracellular pathways involving
protein kinases, such as mitogen-activated protein kinase (MAPK) (Bayram et al., 2006, 088439;
Lee et al., 2005, 156682: Roberts et al., 2003, 156051: Soberanes et al., 2009, 190483): AKT (Ahsan
et al., 2005, 156200): src (Cao et al., 2007, 156322) and epidermal growth factor receptor (Blanchet
et al., 2004, 087982: Cao et al., 2007, 156322: Tamaoki et al., 2004, 157040). as well as ras
(Tamaoki et al., 2004,  157040). toll-like receptors (Becker et al., 2002, 052419: Becker et al., 2005,
088590). protein tyrosine phosphatases (Tal et al., 2006, 108588). phospholipases A2 (Lee  et al.,
2003, 156678). calcium (Agopyan et al., 2003, 155649: Brown et al., 2004,  155705: Brown et al.,
2004, 088663: Geng et al., 2005, 096689: 2006, 097026: Sakamoto et al., 2007, 096282). caspases
(Soberanes et al., 2006, 156991: Zhang et al., 2007, 156179). poly (ADP-ribose) polymerase family
member 1 (PARP-1) (Zhang et al., 2007, 156179) and histone acetylation (Gilmour et al., 2003,
096959). The transcription factors regulated by these pathways, including NF-KB (Bayram et al.,
2006, 088439: Lee et al., 2005, 156682: Takizawa et al., 2003, 157039). activator protein 1 (AP-1)
(Donaldson et  al., 2003, 156408). signal transducers and activators of transcription protein (STAT)
(Cao et al., 2007, 156322). antioxidant response element (ARE) (Li  and Nel, 2006, 156694). and
AhR (Rouse et al., 2008, 156930) have also been studied following PM exposures. Activation of
these intracellular pathways and transcription factors leads to the upregulation of genes responsible
for inflammatory, immune and acute phase responses  as well as genes responsible for antioxidant
defense and xenobiotic metabolism.
5.1.3.   Pulmonary Inflammation
      Following PM exposure, transcription factor activation in macrophages and epithelial cells
stimulates the synthesis and release of soluble mediators involved in inflammatory and immune
responses including cytokines, chemokines, proteases and eicosanoids (Figure 5-3). These
substances play a role in recruiting inflammatory cells such as neutrophils, monocytes, mast cells
and eosinophils to the lung. Interactions between macrophages and epithelial cells enhance these
responses (Tao  and Kobzik, 2002, 157044).
December 2009                                 5-4

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                                                                 Cell Surface
                                                                 Interactions
                                         Endotoxin
                                           Zinc
                                           PAH
• * *
Cell Signaling/
Transcription
Factor Activation

),
/
Cytokines
Chemokines
Proteases
Mediators
                                         Cell Injury
                                   Influx of Leukocytes
                                 Pulmonary Inflammation
Figure 5-3.    PM activates cell signaling pathways leading to pulmonary inflammation.

      Inflammatory cells can serve as a source of extracellular ROS which, along with soluble
mediators derived from the inflammatory cells, amplify the inflammatory response. Unchecked
inflammation may cause cellular and tissue injury through the generation of excess amounts of ROS
and soluble mediators. In some cases the oxidative potential of PM is well-correlated with the degree
of inflammation (Dick et al., 2003, 036605). suggesting that the inflammation is a direct
consequence of PM-generated ROS. However, in other cases the oxidative potential of PM is not
well-correlated with the degree of inflammation (Beck-Speier et al., 2005, 156262). suggesting that
the inflammation is a consequence of the ROS-independent mechanisms by which PM activates
intracellular signaling pathways. Particle surface area has been identified as a key determinant of the
extent of inflammation in the case of low-toxicity, low-solubility particles (Donaldson et al., 2008,
December 2009
5-5

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190217). Moreover, UFPs may cause inflammation disproportionately to their mass compared with
PM of larger sizes given their large surface/volume ratio compared with other PM fractions.
      PM exposure often results in neutrophilic inflammation in laboratory studies (Tao et al., 2003,
156111). Neutrophilic inflammation is also associated with acute lung injury in humans as well as
chronic lung diseases such as COPD and certain forms of asthma (Barnes,  2007, 191139; Cowburn
et al., 2008, 191142). Circulating neutrophils respond to chemotactic factors in the lung such as
leukotriene B4 and IL-8 (Barnes, 2007, 191139). They migrate into the lung parenchyma across the
pulmonary capillary network and into the airways from the bronchial circulation (Cowburn et al.,
2008, 191142). As  a consequence of priming by inflammatory mediators or contact with
extracellular matrix components, neutrophils become hyperresponsive to activating signals and
insensitive to chemotactic signals (Cowburn et al., 2008, 191142). Activation results in neutrophil
degranulation, respiratory burst responses and soluble mediator release (Cowburn et  al., 2008,
191142). Neutrophils eventually undergo apoptosis and are phagocytized by inflammatory
macrophages (Cowburn et al., 2008, 191142). This is accompanied by the release of anti-
inflammatory mediators such as IL-10 and transforming growth factor-|3 (TGF- |3) (Cowburn et al.,
2008, 191142). These steps are key to the resolution of inflammation and prevent unregulated release
of toxic neutrophil products such as neutrophil elastase  (Cowburn et al., 2008, 191142). Thus,
circumstances leading to the decreased ingestion of apoptotic neutrophils by macrophages may lead
to tissue injury. Impairment of macrophage function may serve as an important mechanism by which
PM contributes to disease.


5.1.4.   Respiratory Tract Barrier Function

      Epithelial injury can lead to an increase in permeability of the airway epithelial and
alveolar-capillary barriers (Braude et al., 1986, 155701). Enhanced transport of soluble and possibly
of insoluble PM components into the circulation may occur under these conditions. Increased
epithelial permeability is also associated with enhanced immune responses to proteins, including
allergens, on the epithelial surface, presumably due to the greater availability of antigens to
underlying immune cells (Wan et al., 1999, 191903). Furthermore, endothelial injury can
compromise the integrity of the alveolar-capillary barrier resulting in transvascular fluid and solute
flux (Braude et al., 1986, 155701). Soluble mediators derived from inflammatory and lung cells
(Chang et al., 2005, 097776) and peptides released by some nerve cells (Widdicombe and Lee,
2001, 019049) can increase the permeability of the alveolar-capillary barrier and result in alveolar
edema. Compromised barrier function in the airways may lead to airway edema. Edema occurring
secondarily to nerve cell stimulation is  one component of the process termed neurogenic
inflammation.
      Given the small size of UFPs, modest changes in  epithelial permeability may particularly
affect the disposition of this fraction. Enhanced translocation to interstitial  compartments or to the
circulation may be important sequelae.  A recent study described in Section 4.3.4.3 demonstrated
greater translocation of UFPs compared with PM^sinto the circulation of rodents treated with
endotoxin to induce acute lung injury prior to IT instillation of PM (Chen et al., 2006, 147267).
Furthermore, epithelial injury in another model resulted in greater translocation of UFPs into the
interstitial compartment (Adamson and Prieditis, 1995, 189982).


5.1.5.   Antioxidant Defenses  and Adaptive  Responses

      Antioxidant defenses and adaptive responses are important modulators of oxidative stress and
other cellular stresses resulting from PM exposure. Antioxidants are present in the epithelial lining
fluid in all regions  of the respiratory tract. In addition, they are present in cells of the lung
parenchyma and inflammatory cells found in airways and alveoli. Some antioxidants act directly
against oxidant species (e.g., glutathione, ascorbate, superoxide dismutase) while others act
indirectly (e.g., gamma-glutamylcysteine synthetase [yGCS], glutathione reductase). Furthermore,
some antioxidants (e.g., Phase 2 enzymes heme oxygenase-l[HO-l], NADPH quinone
oxidoreductase 1 [NQO1], glutathione-S-transferase [GST]) are inducible via activation of the
nuclear factor (erythroid-derived 2)- related factor 2 (Nrf2)-ARE pathway,  which occurs as an
adaptive  response to stress (Cho et al., 2006, 156345; Li and Nel, 2006, 156694). Antioxidants play
December 2009                                  5-6

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an important role in reducing the oxidative potential of those PM species that directly generate ROS.
They also inhibit responses due to generation of intracellular ROS.
     Recently a three-tier response to oxidative stress was proposed (Li  and Nel, 2006, 156694). In
this scheme, mild oxidative stress enhances antioxidant defenses by upregulating Phase 2 and other
antioxidant enzymes (Tier 1). Further increase in oxidative stress induces inflammation (Tier 2) and
cell death (Tier 3). Experimental evidence is supportive of this scheme. Numerous studies have
demonstrated that enhancement  of lung and cellular antioxidant defenses inhibits inflammation,
cytotoxicity and other responses following exposure to PM (Ahsan et al, 2005, 156200; Bachoual et
al., 2007, 155667; Bayram et al., 2006, 088439; Chang et al., 2005,  097776; Imrich et al., 2007,
155859; Koike and Kobayashi,  2005, 088303; Koike et al., 2004, 058555; Li et al., 2007, 155929;
Ramage and Guy, 2004, 055640; Rhoden et al., 2004, 087969; Steerenberg et al., 2004, 087981;
Takizawa et al., 2003, 157039; Tao et al., 2003, 156111; Upadhyay et al., 2003, 097370; Wan and
Diaz-Sanchez, 2006, 097399; Wan and Diaz-Sanchez, 2007, 156145; Yin et al., 2004, 087983).
     Cellular and tissue exposure to xenobiotics carried by PM  can lead to induction of Phase 1 and
Phase 2 detoxifying enzymes following the activation of cell signaling pathways and transcription
factors  AhR and ARE, respectively (Rengasamy et al., 2003, 156907; Rouse et al., 2008, 156930;
Zhao et al., 2006, 100996).
    AHR and
      Airway
   Remodeling
Allergic Asthma
   And Other
    Allergic
   Disorders
  Impaired
Host Defense
and Infections
Progression of
 Pre-existing
    Lung
   Disease
DMA Damage
    and
    Lung
   Cancer
      Death or Hospitalization for Asthma, Pneumonia, COPD and Lung Cancer
Figure 5-4.    Potential pathways for the effects of PM on the respiratory system.
December 2009
                         5-7

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5.1.6.   Pulmonary Function

      PM exposure may alter pulmonary function by a variety of different mechanisms (Figure 5-4).
In the short-term, airway hyperresponsiveness (AHR) may ensue due to the influence of
inflammatory mediators. In the long-term, morphological changes may occur, in some cases leading
to mucus hypersecretion and airway remodeling. Activation of irritant receptors and stimulation of
the ANS in the respiratory tract is another mechanism by which PM exposure may alter pulmonary
function (Section 5.4).


5.1.7.  Allergic Disorders

      PM exposure sometimes leads to the development of allergic immune responses (Figure 5-4).
These responses are predominately mediated by T helper 2 cells (Th2). Thl responses, characterized
by IFN-y and classical macrophage activation, are inflammatory; in excess they can lead to tissue
damage. Alternatively, Th2 responses are associated with allergy and asthma and are characterized
by IL-4, IL-5, IL-13, influx of eosinophils, B-lymphocyte production of IgE, and alternative
macrophage activation. PM exposure can also lead to the exacerbation of airway allergic responses,
such as antigen-specific IgE production and AHR.
      Due to soluble mediators and immune cell trafficking, pulmonary exposure may result in
systemic immune alterations. Not only  do macrophages ingest PM, but they are also antigen
presenting cells whose level of activation dictates costimulation and thus subsequent T cell
responses. These cells are highly mobile and can transport PM to other sites such as lymph nodes.
Dendritic cells (DC) also play a key role as antigen presenting cells and in modulating T and B cell
activity. A cell culture model of the human epithelial airway wall was used to demonstrate that DC
extended processes between epithelial cells through the tight junctions, collected particles in the
lumenal space and transported them across the epithelium (Blank et al., 2007, 096521). DC also
transmigrated through the epithelium to take up particles on the epithelial surface (Blank  et al., 2007,
096521). Furthermore, DC  interacted with particle-loaded macrophages on top of the epithelium and
with other DC within or beneath the epithelium to transfer particles (Blank et al., 2007, 096521). In
vitro studies also demonstrated that the adjuvant activity of diesel exhaust particles (DEPs) involved
stimulation of immature monocyte-derived dendritic cells (iMDDC) to undergo maturation in
response to an altered airway epithelial cell-derived microenvironment (Bleck et al., 2006, 096560).
Additionally, DEP directly  influenced the profile of cytokines secreted by DC and caused a
predisposition toward Th2-mediated or allergic responses (Chan et al., 2006,  097468). Thus PM can
negatively affect both innate immunity through effects on macrophage pathogen handling
(Section 5.1.8) as well as adaptive immunity by altering macrophage or DC antigen presenting
activity and subsequent T cell responses.
      Moreover, recent studies have demonstrated that ambient PM can act as an adjuvant for
allergic sensitization with UFPs having a greater effect than fine particles (de Haar et al.,  2006,
144746; Li et al., 2009, 190457). This has  been attributed to higher oxidative potential of the UFPs
compared with the same mass of particles of larger size (Li et al., 2009, 190457). although the larger
surface area and particle number per unit mass as well as the propensity of UFPs for trans-epithelial
movement may also contribute to this effect.


5.1.8.   Impaired Lung  Defense  Mechanisms

      PM exposure may impair lung defense mechanisms and result in frequent or persistent
infections (Figure 5-4). Potential targets include mucociliary transport, surfactant function and
pathogen clearance. Pathogen clearance is dependent on the integrity of macrophages and their
migration, phagocytosis and respiratory burst functions. PM-mediated cytotoxicity of macrophages
with the concomitant release of lysosomal contents may affect pathogen clearance and cause damage
to nearby cells and tissues.  IT instillation and cell culture experiments have demonstrated
PM-dependent impairment of lung defense mechanisms (Jaspers et al., 2005, 088115; Kaan and
Hegele, 2003, 095753: Long et al., 2005, 087454: Moller et al., 2005, 156770: Monn et al., 2003,
052418: Roberts et al., 2007, 097623: Yin  et al., 2004, 087983).
December 2009                                 5-8

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5.1.9.   Resolution of Inflammation/Progression or Exacerbation of

Disease

      Resolution of pulmonary inflammation and injury has been demonstrated in many
experimental models using higher than ambient concentrations of PM. Factors contributing to this
complex process are likely to include the uptake and clearance of PM by macrophages; the retention
of PM in parenchymal cells and tissues; the balance of pro/anti-inflammatory soluble mediators,
oxidants/antioxidants and proteases/anti-proteases; and the presence of pre-existing disease. These
factors may also influence the resolution of pulmonary responses to ambient PM exposures (Figure
5-4). The long-term consequences of prolonged inflammation are not likely to be beneficial and may
lead to remodeling of the respiratory tract and to the progression or exacerbation of disease.


5.1.9.1.   Factors Affecting the Retention of PM

      Clearance of poorly soluble particles from ET, TB and alveolar regions is extensively
discussed in Section 4.3. While clearance from ET and TB regions generally occurs over hours to
days, clearance from the alveolar compartment is much slower, occurring over months to years
depending on the species. Phagocytosis by alveolar macrophages and transport by the mucociliary
escalator is the primary mechanism of clearance from the alveolar  compartment although neutrophil
phagocytosis also plays a role (Snipes et al, 1997, 156092). Pre-existing disease can alter the extent
and localization of PM deposition as discussed in Section 4.2.4.5. In addition, mechanisms of
clearance may be altered in cases of pre-existing disease as discussed in Section 4.3.4.3. While mild
asthma was associated with enhanced mucociliary clearance, acute lung injury was associated with
enhanced particle translocation to the circulation and the interstitial compartment.  Whether retained
particles are localized in alveolar macrophages or parenchymal tissue also differs according to
species (Snipes, 1996, 076041).
      UFPs may have a special propensity for retention given the decreased efficiency of alveolar
macrophages for phagocytosis of this size particle (Oberdorster, 1988, 006857) and the
demonstration that UFPs can readily cross cellular membranes (Geiser et al., 2005, 087362). Some
studies suggest that UFPs are taken up by epithelial cells and move to the interstitum where they are
cleared by other pathways (Semmler-Behnke et al., 2007, 156080); however clearance mechanisms
are not entirely  understood.
      Enhanced deposition of particles in "hot spots" may influence retention. For example,
deposition in the centriacinar or proximal alveolar region, where clearance is slow, may result in
accumulated particle dose in this region and the potential for prolonged inflammation at the site
leading to the development of pulmonary fibrosis or emphysema (Donaldson et al., 2008, 190217). A
recent study suggests an important role for retained particles in the progression of disease.
Complexation of endogenous iron by retained particles resulted in  retained particles growing larger
over time. The authors suggested that redox cycling of complexed  iron may be responsible for
disease progression (Ohio  and Cohen, 2005, 088272: Ohio et al., 2004, 155790).


5.1.9.2.   Factors Affecting the Balance of Pro/Anti-Inflammatory Mediators,
Oxidants/Anti-Oxidants and Proteases/Anti-Proteases

      Inflammation can be enhanced by pro-inflammatory mediators or dampened by anti-
inflammatory mediators. Production of anti-inflammatory mediators normally occurs at several steps
of the inflammation pathway, such as the release of IL-10 and TGF-(3 during phagocytosis of
apoptotic neutrophils by macrophages (Cowburn et al., 2008,  191142). Dsyregulation of the
inflammatory process may prevent the resolution of inflammation. PM exposure may result in the
production of pro-inflammatory mediators as well as decrease the production of anti-inflammatory
mediators by impairing macrophage function.
      An unfavorable balance of oxidants to antioxidants in the lung is associated with inflammatory
lung diseases including asthma and COPD (Rahman et al., 2006, 191165). PM is likely to contribute
to an unfavorable balance through its oxidative potential and capacity to promote cellular production
of ROS. Exacerbations of asthma and COPD resulting from bacterial and viral infections are also
associated with increased oxidative stress (Barnes, 2007, 191139).  Conversely, antioxidants may
reduce neutrophilic inflammation associated with oxidative stress (Barnes, 2007, 191139).
December 2009                                  5-9

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      Protease/anti-protease balance has long been tied to the pathogenesis of emphysema and other
forms of COPD (Owen, 2008, 191162). Key steps include the release of proteinases by inflammatory
cells which degrade the extracellular matrix components of alveolar walls. Destruction of alveolar
walls and airspace enlargement ensues. Endogenous anti-protease defenses in the lung modulate this
response but may be insufficient to prevent it during prolonged inflammation. Proteases also play a
role in pathologies which lead to small airway fibrosis (Owen, 2008, 191162). Oxidative stress has
been linked to both activation of proteases and inactivation  of anti-proteases (Owen, 2008, 191162).
PM may contribute to an unfavorable protease/anti-protease balance through the generation  of ROS.
      Although there are numerous inflammatory cell-derived proteases and lung anti-proteases,
many recent studies have focused on matrix metalloproteinases (MMPs). MMPs are a family of Zn-
containing enzymes normally found in an inactive pro-enzyme form. Activation involves proteolytic
cleavage or oxidation of the "cysteine switch" (Pardo  and Selman, 2005, 191163).  Inhibitors include
tissue inhibitors of metalloproteinases (TIMPs) (Pardo  and Selman, 2005, 191163). In particular,
MMP-1 is well-studied and found to play an important role in physiological processes such  as
development and wound repair as well as in diseases such as pulmonary emphysema, fibrosis,
asthma and bronchial carcinoma (Li et al., 2009, 190424; Pardo and Selman, 2005, 191163). In
addition to its activity in degrading collagenase, MMP-1 also acts on non-matrix substrates and cell
surface molecules suggesting that it may influence cell signaling (Pardo and Selman, 2005,  191163).
MMP-2 and MMP-9 are thought to be involved in the pathogenesis of disease through their
gelatinase activity. Interestingly, recent in vitro studies have demonstrated upregulation of MMP-1
by hydrogen peroxide, cigarette smoke and DEPs (Amara et al., 2007, 156212; Li et al., 2009,
190424; Mercer et al., 2004, 191180). and up-regulation of MMP-12 following instillation of PM
collected from the Paris subway (Bachoual et al.,  2007, 155667). These considerations suggest that
particulate air pollution may act via MMP to mediate progression or exacerbation of lung disease.


5.1.9.3.   Pre-Existing Disease

      In addition to its effects on deposition, retention and clearance of PM described above, pre-
existing disease may also alter the balance of the aforementioned factors. For example, acute
exacerbations of COPD are characterized by a rapid influx of neutrophils into the airways (Owen,
2008, 191162). However, clearance  of apoptotic neutrophils by macrophages is impaired in  COPD
leading to greater release of neutrophil-derived inflammatory mediators, oxidants and proteases
(Owen, 2008, 191162). Thus, exacerbation of disease may occur as a result of unchecked
inflammation.


5.1.10. Pulmonary DMA Damage

      Pulmonary DNA damage can occur primarily or secondarily to  PM exposure. Primary effects
include oxidative DNA injury or DNA adduct formation due directly to  PM while secondary effects
occur due to PM-mediated inflammation (De Kok et al., 2005, 088656;  Gabelova et al., 2007,
156457; Gallagher et al., 2003, 140171; Schins and Knaapen, 2007, 156074). These responses may
lead to chromosomal aberrations or DNA strand breaks. PM effects on cell cycle arrest, proliferation,
apoptosis, and DNA repair mechanisms may also influence  the genotoxic, mutagenic or carcinogenic
potential of DNA damage as reviewed by Schins et al. (2007, 156074).


5.1.11. Epigenetic Changes

      Epigenetic mechanisms regulate the transcription of genes without altering the nucleotide
sequence of DNA. These mechanisms generally involve DNA methylation and histone
modifications, leading to alterations which may have long-term consequences or are heritable (Jones
and Baylin, 2007, 191153; Keverne and Curley, 2008, 191154). DNA methylation  and histone
modifications, which include methylation, acetylation, phosphorylation, ubiquitylation and
sumoylation, are known to be linked (Hitchler and Domann, 2007, 191151; Jones  and Baylin, 2007,
191153). Numerous studies have identified epigenetic processes in the control of cancer (Foley et al.,
2009, 191144; Gopalakrishnan et al., 2008, 191147; Jones and Baylin, 2007, 191153; Valinluck et
al., 2004, 191170). embryonic development (Foley et al., 2009, 191144; Gopalakrishnan et al., 2008,
December 2009                                  5-10

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191147; Keverne and Curley, 2008, 191154) and inflammation and other immune system functions
(Adcock et al., 2007, 191178).
      Epigenetic modifications resulting in decreased expression of tumor suppressor genes and
increased expression of transforming genes have been observed in human tumors (Valinluck et al.,
2004, 191170). In general, transcription repression is associated with DNA methylation in promoter
regions of genes. Cytosine methylation in CpG dinucleotides has emerged as an important, heritable
epigenetic modification which can result in chromatin remodeling and decreased gene expression
(Valinluck et al., 2004, 191170). Global changes in DNA methylation are also seen in cancer and
hypomethylation is associated with genomic instability  (Gopalakrishnan et al., 2008, 191147).
      Embryonic development is characterized by several phases of epigenetic modifications. DNA
methylation is very dynamic following fertilization, with demethylation and re-methylation of egg
and sperm genomes occurring immediately (Foley et al., 2009, 191144). Imprinted genes, however,
retain the methylation profile of the parent of origin (Foley et al., 2009,  191144). Epigenetic changes
accumulated through a life course may be passed from parent to offspring in the germline (i.e.,
germline transmission of epimutation) if they survive the epigenetic remodeling that occurs during
gametogenesis and early embryogenesis (Foley et al., 2009, 191144).  Early development is
characterized by the process of cell differentiation, which produces different cell types and involves
the selective activation of some sets of genes and the silencing of others in a temporal pattern (Foley
et al., 2009, 191144; Gopalakrishnan et al., 2008, 191147). DNA methylation is postulated to provide
a basis for cell differentiation (Gopalakrishnan et al., 2008, 191147).
      In the lung, histone acetylation and methylation have been linked to inflammatory gene
expression, T cell differentiation, and the regulation of macrophage function following pathogen
challenge (Adcock et al., 2007, 191178). Furthermore, altered patterns of methylation and
acetylation have been reported in inflammatory diseases (Adcock et al., 2007, 191178). Reduced
expression and activity of histone deacetylase have been demonstrated in lung and inflammatory
cells in COPD and asthma (Adcock et al., 2007,  191178; Barnes, 2007,  191139).  Consequently,
histone deacetylase has been identified as a potential therapeutic target for epigenetic therapy
(Adcock et al., 2007, 191178; Jones and Baylin, 2007,  191153).
      Epigenetic mechanisms have been identified as potential targets for gene-environment
interactions and recent studies have demonstrated that diet, cigarette smoking, endocrine disrupters,
heavy metals and bacterial infection can alter the epigenetic profile in animals and humans (Foley et
al., 2009, 191144). A role for PM in promoting epigenetic changes has been proposed and new
studies, discussed in later chapters,  provide some evidence for this pathway (Baccarelli et al., 2009,
192155; Liu et al., 2008, 156709; Reed et al., 2008, 156903; Tarantini et al., 2009, 192010; Tarantini
et al., 2009, 192153; Yauk et al., 2008, 157164).
      Early life exposures may be especially important in this regard since periods of rapid cell
division and epigenetic remodeling are likely to occur at this time (Foley et al., 2009, 191144;
Keverne  and Curley, 2008, 191154; Wright and Baccarelli, 2007, 191173). This may provide a basis
for fetal origins of adult disease.
      It has been suggested that DNA methylation is regulated by oxygen gradients and redox status
(Hitchler and Domann, 2007, 191151). While this is of particular importance during development
where oxygen gradients and redox status are linked to cellular differentiation, these processes are
also important for cell signaling during all stages of life. A common metabolic precursor for both
methylation reactions and glutathione availability (involved in  redox status) is methionine (Hitchler
and Domann, 2007, 191151). Methionine availability regulates the cell's ability to generate
S-adenosyl methionine which is directly involved in DNA and histone methylation and the cell's
ability to generate homocysteine/cysteine which is involved in  glutathione biosynthesis (Hitchler
and Domann, 2007, 191151). Furthermore, the folate cycle is a key determinant of methionine
bioavailability (Hitchler and Domann, 2007, 191151). In this way, cellular intermediary metabolism
is linked to epigenetic processes,  with oxidative stress necessitating a metabolic shift resulting in
decreased DNA methylation and increased glutathione production.


5.1.12. Lung Development

      Lung development is a multi-step process which begins in embryogenesis and continues to
adult life (Pinkerton  and Joad, 2006, 091237). This allows for  a long  period of potential
vulnerability to environmental and other stressors. Furthermore, enzymatic systems responsible for
detoxification of xenobiotic compounds are not fully developed until the postnatal period (Pinkerton
December 2009                                  5-11

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and Joad, 2006, 091237). Disruption of cell signaling during development could affect cellular
differentiation, branching morphogenesis and overall lung growth, possibly leading to life-long
consequences. Although very little is known about the effects of maternal exposure to PM on the
fetus or the effects of exposure during childhood, recent animal studies demonstrate respiratory and
immune system effects of perinatal exposure to sidestream cigarette smoke (Pinkerton and Joad,
2006, 091237: Wang and Pinkerton, 2007, 1799751
5.2.  Systemic Inflammation
      Pulmonary inflammation resulting from PM exposure may trigger systemic inflammation
through the action of cytokines and other soluble mediators which leave the lung and enter the
circulation (Figure 5-5). Epithelial permeability may exert an important influence on this process
(Section 5.1.4). Cytokines released by alveolar macrophages can stimulate bone marrow production
of leukocytes resulting in an increased number of total and immature leukocytes in the circulation
(Van  and Hogg, 2002, 088111: Van Eeden et al, 2001, 019018). They also can activate neutrophils
and promote their sequestration in microvascular beds (Van Eeden et al., 2001, 019018). The time
course of these responses varies according to the acute or chronic nature of the PM exposure
(van Eeden et al., 2005, 157086).
      Systemic inflammation is seen under conditions of mild pulmonary inflammation  - and
sometimes under conditions of no measurable pulmonary inflammation - following PM exposure.
The time-dependent nature of pulmonary and systemic inflammatory responses may in part explain
these findings since biomarkers of inflammation are frequently measured only at one time point.
Furthermore, chronic exposures may lead to adaptive responses. In general, systemic inflammation is
associated with changes in circulating white blood cells, the acute phase response, pro-coagulation
effects, endothelial dysfunction and the development of atherosclerosis (Figure 5-5). Adverse effects
on the cardiovascular and  cerebrovascular systems such as thrombosis, plaque rupture, MI and stroke
may result.  Systemic inflammation may affect other organ systems such as the liver or the CNS.
      One recent study demonstrated that alveolar macrophage-derived IL-6 mediated
pro-coagulation effects in  mice exposed by IT instillation to PMi0 (Mutlu et al., 2007, 121441). This
study  provides a clear link between lung cytokines and systemic responses in one model system.
Whether this mechanism or others account for the majority of extra-pulmonary effects following
inhalation of PM at concentrations relevant to ambient exposures is not yet known.
December 2009                                 5-12

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                Pulmonary
             Oxidative Stress
             and Inflammation
               Direct Effects ?
           Translocation/Absorption
            of Soluble Components
                                       Pulmonary Reflexes
                                        Other Reflexes ?
                                                                  Autonomic
                                                                Nervous System
           Liver
          Acute
          Phase
         Response
                                                               Altered Sympathetic/
                                                                Parasympathetic
                                                                     Tone
                            Atherosclerosis
                       Plaque Destabihzation
                           Or Rupture
            Death or
         Hospitalization
          for Throm bo-
         Em bolic Disease
Death or Hospitalization
     for Stroke
  Death or Hospitalization for Coronary
Heart Disease or Congestive Heart Failure
Figure 5-5.     Potential pathways for the effects of PM on the cardiovascular system.
5.2.1.   Endothelial  Dysfunction and Altered Vasoreactivity
      The lumenal surface of blood vessels is lined by endothelial cells which, in addition to
providing a barrier function, are key regulators of vascular homeostasis. Endothelial cells synthesize
and release vasodilators such as nitric oxide (NO) and prostacyclin and vasoconstrictors such as
endothelin (ET), which act on neighboring smooth muscle cells. ET also stimulates endothelial NO
synthesis through a feedback mechanism. Inhalation of high concentrations of PM has been reported
to increase ET levels in the circulation (Thomson et al, 2005, 087554). ET has also been proposed to
play a role in hypoxia-induced MI (Caligiuri et al.,  1999, 156318). However, the role of ET in
mediating cardiovascular  effects following ambient PM exposures is unclear (Section 6.2.4.3).
December 2009
                      5-13

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      Endothelial dysfunction can lead to or follow endothelial activation under conditions of
systemic inflammation and/or vascular oxidative stress. Both systemic inflammation and vascular
oxidative stress have been associated with PM exposure (Nurkiewicz et al., 2006, 088611;
Van Eeden et al., 2001, 019018). Cytokines activate endothelial cells and upregulate endothelial cell
adhesion molecules. They also promote the sequestration of neutrophils in microvascular beds.
Neutrophil sequestration is sometimes associated with the deposition of myeloperoxidase (MPO) on
endothelial cell surfaces (Nurkiewicz et al., 2006, 088611).  ROS-derived from neutrophils, MPO,
other adhered inflammatory cells and/or other sources can perturb the balance of vasodilator and
vasoconstrictor species produced by endothelial cells. Oxidative stress can result in decreased
synthesis of NO due to limitation of the redox-sensitive essential cofactor tetrahydrobiopterin and in
decreased bioavailability  of NO due to reaction with superoxide.  Prostacyclin synthesis is also
decreased by oxidative stress. Importantly, these processes can affect vasoreactivity such that blood
vessels may be unable to  respond to vasoconstrictor stimuli with  compensatory vasodilation.
      Loss of NO and prostacyclin synthesis  due to PM-dependent vascular oxidative stress may
have other consequences  since both exert negative influences on platelet and neutrophil activation.
While endothelial surfaces normally are anti-thrombotic, endothelial dysfunction can contribute to
thrombus formation.  Furthermore, inflammation and oxidative stress associated with endothelial
dysfunction can contribute to the development or progression of atherosclerosis (van Eeden et al.,
2005, 157086).


5.2.2.   Activation of Coagulation  and Acute Phase Response

      The primary function of the coagulation cascade is to stop the loss of blood after vascular
injury by forming a fibrin clot. However in some cases, activation of coagulation can promote
intravascular thrombosis (Karoly et al., 2007, 155890). It has been proposed that air pollution-
associated PM can activate clotting pathways and enhance the likelihood of an obstructive cardiac
ischemic event (e.g.,  MI)  or cerebral event (e.g., stroke) (Seaton et al., 1995,  045721).
      Coagulation is regulated by intrinsic and extrinsic pathways. The intrinsic pathway occurs
following activation of Factor XII and does not require the addition of an exogenous agent
(Mackman, 2005, 156722).  On the other hand, the extrinsic pathway is an inducible signaling
cascade that can be activated by tissue factor  (TF) produced in response to inflammation or
endothelial injury (Karoly et al., 2007, 155890).
      In general, platelets, red blood cells (RBCs)  and endothelial cells are effector cells for
inducing a pro-coagulant  state in the vasculature. Circulating factors may enhance coagulation or
promote activation of platelets. Cytokines formed during tissue damage and inflammation lead to TF
induction. TF is the initiating stimulus for coagulation following vascular injury or plaque erosion.
Complexes of TF:Factor Vila form on endothelial  cell surfaces and play a key role in thrombin
generation by initiating the extrinsic blood coagulation pathway (Gilmour et al., 2005, 087410).
Thrombin generates fibrin from fibrinogen and amplifies the intrinsic pathway (Karoly et al., 2007,
155890). TF and thrombin also have pro-inflammatory actions independent of coagulation functions
(Chu, 2005,  155730); thus activation of coagulation may lead to or potentiate inflammation.
Endothelial cell-derived von Willebrand factor also contributes to coagulation.
      The fibrinolytic system opposes these processes by facilitating the removal of a clot.  The
fibrinolytic pathway is regulated by the ratio  of tissue plasminogen activator  (tPA) and plasminogen
activator inhibitor (PAI). Furthermore, the endothelial cell surface has anti-thrombotic properties due
to the expression of tissue factor pathway inhibitor (TFPI) and thrombomodulin (Mackman, 2005,
156722).
      Inhibition of the fibrinolytic pathway, along  with increased plasma viscosity and increased
concentrations of plasma  fibrinogen and Factor VII, contributes to a pro-thrombotic state (Gilmour et
al., 2005, 087410). In acute lung injury, vascular cells have  enhanced pro-coagulant activity and
impaired fibrinolytic activity (Gilmour et al.,  2005, 087410). In arterial atherosclerosis, TF
expression is increased within plaques. As a result, spontaneous plaque rupture may trigger
intravascular clotting (Karoly et al., 2007, 155890).
      Acute phase responses also play a role  in hemostasis by exerting pro-coagulant effects.
Cytokines such as IL-6 stimulate the liver to produce acute phase proteins including C-reactive
protein (CRP), fibrinogen and antiproteases (van Eeden et al., 2005, 157086). To date, there is
limited evidence supporting a role for ambient PM in stimulating acute phase responses (Ruckerl et
al., 2007, 156931 and reviewed therein) (also Section 6.2.7  and 6.2.8 in this ISA).
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5.2.3.   Atherosclerosis

      Atherosclerosis is a chronic progressive disease which contributes greatly to cardiovascular
morbidity (Libby, 2002, 192009).  Mainly a disease of the large arteries, it is characterized by the
accumulation of lipid and fibrous tissue in atheromas, or swellings of the vessel wall (Libby, 2002,
192009). Although a strong link is known to exist between hypercholesterolemia and atherogenesis,
there is growing appreciation of the key role played by inflammation in the initiation and progression
of atherosclerosis (Libby, 2002, 192009). Furthermore, inflammation has the potential to promote
thrombosis which can complicate  this disorder and lead to MI and stroke (Libby, 2002, 192009). As
discussed above, PM exposure is associated with systemic inflammation, potentially contributing to
the development of atherosclerosis.
      Atheroma formation in experimental animals fed a high fat diet begins with the accumulation
of modified lipoprotein particles in the arterial intima, as reviewed by Libby (2002, 192009). The
modification of lipoprotein particles often involves oxidation. As discussed above, PM exposure is
associated with oxidative stress, suggesting a potential role for PM in the modification of lipoprotein
particles. Endothelial dysfunction  may also be key to these early events (Halvorsen et al., 2008,
191149). Recent studies, which are discussed in later chapters, demonstrate PM-dependent
endothelial dysfunction (Nurkiewicz et al., 2009, 191961). As described by Libby (2002, 192009).
oxidative stress leads to lipid modification and uptake by endothelial cells and initiates an
inflammatory response by activating NF-KB. As a result, cell adhesion molecules such  as vascular
cell adhesion molecule-1 (VCAM-1) are upregulated and expressed  in endothelial cells. Pro-
inflammatory cytokines associated with systemic inflammation may also contribute to adhesion
molecule upregulation. Subsequently, monocytes and T cell lymphocytes adhere to the activated
endothelium, then migrate into the tunica intima directed by chemokines such as monocyte
chemoattractant protein-1 (MCP-1) and IL-8. Monocytes undergo transformation to tissue
macrophages and later to foam cells. As a part of this transformation, monocyte/macrophages
express scavenger receptors and bind to and internalize the modified lipoprotein particles. These
cells secrete growth factors  and cytokines, produce ROS, replicate within the lesion and contribute to
further lesion progression. Macrophage colony-stimulating factor (M-CSF) and granulocyte-
macrophage colony-stimulating factor (GM-CSF) are thought to be involved in these latter steps
which eventually lead to the formation of a fatty streak.  T cell lymphocytes also become activated in
the atheroma and secrete pro- or anti-inflammatory cytokines. Degranulation of mast cells found in
the atheroma may also contribute to the lesion.
      Atheroma progression involves the proliferation of smooth muscle cells,  which is stimulated
by macrophage-derived growth factors (Libby, 2002, 192009). This  results in smooth muscle
accumulation in the lesion, the elaboration of extracellular matrix material and the formation of a
more bulky lesion which can occlude the arterial lumen. Matrix proteins contribute to the evolution
of the lesion from a fatty streak to a fibrous plaque. Mechanisms which trigger plaque disruption,
including endothelial erosions and plaque rupture,  can result in thrombosis as well as in further
expansion of the lesion. Resident T cells, mast cells and circulating platelets may also play a role in
destabilizing plaques (Halvorsen et al., 2008, 191149). It is thought that most atheromatous lesions
progress  in a discontinuous  manner due to cycles of disruption, expansion and repair.
      A major factor regulating plaque disruption is the thickness of the fibrous cap, with more
stable plaques  characterized by a thick fibrous cap (Libby, 2002, 192009). Collagen in the fibrous
cap can be degraded by proteases, especially MMPs. Inflammation in the intima reduces collagen
production by  smooth muscle cells and promotes the expression and activation  of MMPs. ROS may
mediate MMP upregulation (Lund et al., 2009, 180257). Both macrophages and smooth muscle cells
produce MMPs in the lesion areas (Halvorsen et al., 2008, 191149):  fully differentiated macrophages
selectively upregulate certain MMPs with more destructive potential (Newby, 2008,  191161).
Rupture of the fibrous cap allows pro-thrombotic factors within the plaque (e.g., TF) to come into
contact with coagulation factors in the blood possibly resulting in the formation of an occlusive
blood clot. However in some cases, blood fibrinolytic mechanisms minimize clot formation and
repair processes ensue. The result  is a more fibrous plaque and/or an expanded lesion. The proposed
role of PM in activating coagulation pathways, which was discussed above, may influence the
outcome of plaque disruption.
      In this manner oxidative stress, inflammation and pro-coagulant activity in the blood are
involved in the initiation and progression of atheromatous lesions as well as plaque disruption and
occlusive blood clot formation. PM exposure may  contribute to these pathways and in fact, studies
December 2009                                  5-15

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described in later chapters demonstrate PM-dependent effects on atherosclerosis progression (Araujo
et al, 2008, 156222; Chen  and Nadziejko, 2005, 087219; Sun et al., 2005, 087952; Ying et al,
2009, 190111).



5.3.  Activation  of the Autonomic Nervous System  by

Pulmonary Reflexes

     Chemosensitive receptors, including rapidly adapting receptors (RARs) and sensory C-fiber
receptors, are found at all levels of the respiratory tract and are sensitive to irritant particles as well
as to irritant gases (Alarie, 1973, 070967; Coleridge and Coleridge, 1994,  156362; Widdicombe,
2006, 155519). Activation of trigeminal afferents in the nose causes CNS reflexes resulting in
decreases in respiratory rate through a lengthened expiratory phase, closure of the glottis, closure of
the nares with increased nasal airflow resistance and effects on the cardiovascular system such as
bradycardia, peripheral vasoconstriction and a rise in systolic arterial blood pressure (Alarie, 1973,
070967). Sneezing, rhinorrhea and vasodilation with subsequent nasal vascular congestion are also
nasal reflex responses involving the trigeminal nerve (Sarin et al., 2006, 191166). Activation of vagal
afferents in the tracheobronchial and alveolar regions of the respiratory tract causes CNS reflexes
resulting in bronchoconstriction, mucus secretion, mucosal vasodilation, cough, apnea followed by
rapid shallow breathing and effects on the cardiovascular system such as bradycardia and
hypotension or hypertension (Coleridge and Coleridge, 1994, 156362; Widdicombe, 2003, 157145;
2006, 155519; Widdicombe and Lee, 2001, 019049). Some evidence suggests that cardiovascular
responses may be mediated primarily by the C-fiber receptors (Coleridge  and Coleridge, 1994,
156362) and that irritants in the lower respiratory tract cause more pronounced cardiovascular
responses than irritants in the upper respiratory tract (Widdicombe and Lee, 2001, 019049).
     Early experiments demonstrated that sectioning of the trigeminal nerve abrogated irritant
effects on respiratory rate, heart rate and systolic arterial blood pressure (Alarie, 1973, 070967).
These nasal reflexes were attributed to the ophthalmic branch of the trigeminal nerve since they were
identical to reflex responses following diving or immersion of the face in water (Alarie, 1973,
070967). Early experiments also demonstrated that non-nasal reflexes  were mediated by cholinergic
parasympathetic pathways involving the vagus nerve and inhibited by  atropine (Grunstein et al.,
1977, 071445; Nadel et al., 1965, 014846). More recent experiments have shown that noncholinergic
mechanisms may also be involved. For example, stimulation of C-fiber receptors can activate local
axon reflexes. These local axon pathways are responsible for secretion of neuropeptides and the
development of neurogenic inflammation (Widdicombe and Lee, 2001, 019049). It has been
proposed that, in some cases, neurogenic pulmonary responses can switch from their normally
protective function to one that perpetuates pulmonary inflammation (Wong et  al., 2003, 097707).
Differences in respiratory tract innervation between rodents and humans suggest that C-fiber
mediated neurogenic inflammation may be more important in rodents than in humans (Groneberg et
al., 2004, 138134; Widdicombe, 2003, 157145; Widdicombe  and Lee, 2001, 019049) However, the
role of neurogenic inflammation in mediating pulmonary responses in humans is an active area of
investigation.
     VR1 receptors represent a subset of neuropeptide and acid-sensitive irritant receptors which
belong to the transient receptor potential (TRP) family. They are located on the sensory C-fibers
which lie underneath and between lung epithelial cells and on immune and non-immune airway
cells. Some investigators have focused on the role played by these receptors in mediating
inflammation following exposure to PM (Veronesi  and Oortgiesen, 2001, 015977). Exposure of
bronchial epithelial cells and neurons to PM in vitro has been shown to result in an immediate
increase in intracellular calcium followed by the release of neuropeptides and  inflammatory
cytokines (Veronesi et al.,  1999, 048764; Veronesi et al., 2000, 017062). In one study, this response
was found to be due to an intrinsic property of the particle core  and was not metal-dependent
(Oortgiesen et al.,  2000, 013998).  while in another study electrostatic charge was found to activate
VR1 receptors (Veronesi et al., 2003, 094384). PM-mediated activation of VR1 receptors which
results  in increases in intracellular calcium and apoptosis in epithelial cells has also been
demonstrated (Agopyan et al., 2003, 155649). New studies, discussed  in later  chapters, provide
evidence for the involvement of TRP VI irritant receptor involvement in PM-dependent responses
(Ghelfi et al.,  2008, 156468; Rhoden et al., 2005, 087878).
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      Recently it has been proposed that pulmonary reflex responses may be modulated by CNS
plasticity (Bonham et al, 2006, 191140; Sekizawa et al., 2008, 191167). Plasticity is a property of
neurons or synapses which allows change in response to previous events. In the case of the
respiratory tract, visceral afferent inputs to the CNS are integrated primarily in the nucleus tractus
soltarius (NTS) region of the brain (Bonham et al., 2006, 191140). Inputs from local networks,
higher brain regions and circulating mediators contribute to the reflex output (Bonham et al., 2006,
191140). This integration allows for plasticity in that repeated or prolonged exposure to  a particular
stimuli may lead to altered reflex responses to the same or subsequent stimuli. An exaggerated reflex
response was recently observed in guinea pigs exposed to ETS for an extended period of time
(Sekizawa et al., 2008, 191167). It is not known whether CNS plasticity influences responses
following  acute and chronic exposure to ambient PM, but it is a mechanism that may possibly
explain hyperresponsiveness and/or adaptation of reflex-related responses.
      At this time, it is not clear how activation of the ANS by pulmonary reflexes contributes to the
kinds of altered conduction and/or repolarization  properties of the heart which may be linked to
arrhythmias  (Figure 5-5). Pulmonary reflexes, as  they are currently understood, initially lead to
increases in parasympathetic tone. However, decreased heart rate variability appears to be reflective
of decreased parasympathetic tone and/or increased sympathetic tone. A PM-dependent sympathetic
stress response mediated by cytokines has been postulated (Godleski et al., 2000,  000738). but there
is little new information to support this mechanism. Thus, activation of the autonomic nervous
system by mechanisms other than pulmonary reflexes seems likely in response to PM. Very little is
known about putative alternative mechanisms leading to sympathoexcitatory responses although one
study demonstrated a role for the olfactory bulb-NTS pathway in regulating cardiovascular functions
following  smoke exposure (Moffitt et al., 2002, 191160). In addition, sympathoexcitatory responses
occur during myocardial ischemia, mediated by the release of adenosine or the production of ROS
by the myocardium (Longhurst et al., 2001, 191158). Hence, PM-dependent effects leading to
myocardial ischemia may stimulate sympathoexcitatory responses.  Furthermore, the effects of
pre-existing  alterations in the ANS due to disease processes (e.g., increased sympathetic tone
observed in cardiac diseases) on PM responses are not understood.  Possibly, integration of neural
signals resulting from pulmonary and cardiac reflexes at the level of the NTS may have  an influence
on ANS responses to PM. Further investigation will be required to clarify these mechanisms.



5.4. Translocation  of UFPs or Soluble PM Components

      UFPs can translocate across cell membranes by non-endocytotic mechanisms involving
adhesive interactions and diffusion (Geiser et al.,  2005, 087362). as described in Section 4.3.3.1. In
this study, there was no measurable loss of PM from the lung over 24 h despite the rapid
translocation of inhaled UFPs into alveolar epithelial cells and capillary endothelial  cells. In another
study, UFPs  were  localized in macrophage mitochondria as demonstrated by electron microscopy (Li
et al., 2003, 042082). Other studies found extrapulmonary translocation of poorly soluble UFPs, but
the process was slow and resulted in only a small amount leaving the lung. It is possible that in these
studies PM gained access to the circulation after initial transport to the lymph nodes or the
gastrointestinal system. Hence, there is limited evidence to date that UFPs or other PM  size
fractions access the circulation by traversing the epithelial barrier of the respiratory tract.
      However, soluble components from all size fractions of PM have the potential to translocate
across the airway  epithelium into the bronchial circulation or across the alveolar epithelium into the
systemic circulation as depicted in Figure 5-5. Absorption across nasal epithelium may also occur
(Ilium, 2006, 191205). Factors affecting this process include the rate of dissolution of the solute
from the particle and the molecular weight of the solute (Section 4.4). More rapid dissolution of
soluble components may occur in the case of UFPs due to the higher surface/volume ratios compared
with larger particles.
      Several interesting studies investigated the  translocation of water-soluble metals from the  lung.
Gilmour et al. (2006, 156472) demonstrated the rapid appearance of Zn in the plasma of rats
following  IT instillation of zinc sulfate (ZnSO4). Similarly, Wallenborn et al.  (2007, 156144)
demonstrated the rapid appearance of water-soluble metals in the blood, heart and liver following IT
instillation of oil combustion PM in rats. Using a more sensitive technique, these same investigators
demonstrated the accumulation of 70Zn, a rare isotope of Zn, in blood, heart and liver following IT
December 2009                                 5-17

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instillation of ZnSO4 (Wallenborn et al., 2009, 191172). In three other studies, soluble Zn and Cu
were associated with cardiac effects following IT instillation of rats with different forms of Zn- and
Cu-containing PM (Gilmour et al., 2006, 088489; Gottipolu et al., 2008, 191148; Kodavanti et al.,
2008, 155907). These results suggest the possibility that PM-derived soluble Zn and Cu translocated
across the alveolar-capillary barrier into the circulation and exerted effects on the heart. However, in
the two studies in which barrier function was measured it was found to be compromised (Gilmour et
al., 2006, 088489; Gottipolu et al., 2008, 191148) suggesting an acute lung injury response to IT
instillation of high concentrations of metal. Acute lung injury is not likely to occur in healthy
individuals exposed to PM at concentrations relevant to ambient levels. Cardiac effects were also
observed following subchronic inhalation exposure to low concentrations of aerosolized ZnSO4
(Wallenborn et al., 2008, 191171).  Since it was not possible to  measure extra-pulmonary Zn in this
study, it remains unclear whether cardiac effects were a direct effect of translocated Zn or an indirect
effect of exposure to Zn-containing PM. Nonetheless, translocation of soluble components derived
from inhaled PM remains a viable hypothesis to explain some extra-pulmonary effects.
      Epithelial permeability is a key determinant of translocation and is discussed in detail in
Section 4.4.2. In brief, a number of studies have measured clearance of 99mTc-DTPA as an index of
alveolar epithelial membrane integrity and permeability of alveolar-capillary barrier (Braude et al.,
1986, 155701). Endothelial integrity also contributes to the alveolar-capillary barrier and is measured
by transvascular protein flux but is not discussed here (Braude et al.,  1986, 155701). In laboratory
animals, increased alveolar permeability was shown  in terminally senescent mice (Tankersley et al.,
2003, 096363).  In human volunteers, epithelial permeability was transiently increased following 3 h
of moderate  exercise but not following 24-h exposure to particle-rich urban  air (Brauner et al., 2009,
190244). A previous study found that the exercise-induced increase in epithelial permeability was
transient and suggested that it was  due to increased ventilation and elevated vascular pressure which
altered the properties of tight junctions (Hanel et al.,  2003,  155826). Smokers (Jones et al., 1983,
155884) and individuals with acute respiratory distress syndrome (Braude et al., 1986, 155701) or
interstitial lung disease (Rinderknecht et al., 1980, 191965) also exhibited increased alveolar
epithelial permeability. The changes in smokers were reversible upon cessation of smoking.
Increased airway epithelial permeability was found in asthmatics when  99mTc-DTPA clearance was
used to measure the permeability of the bronchial mucosa (Ilowite et al., 1989, 156584). These
studies demonstrate that epithelial permeability is increased following moderate exercise and in lung
syndromes associated with inflammation and suggest that compromised epithelial barrier functions
in the lung may contribute to PM-mediated effects.
      Interaction of circulating PM or soluble PM components with vascular endothelial cells,
platelets, and other leukocytes is a potential mechanism underlying the cardiovascular and systemic
effects of inhaled PM.  A role for PM-derived ROS and/or cellular-derived ROS has been proposed.
Furthermore, soluble metals that do not redox-cycle may activate cell signaling pathways without the
generation of ROS. In  this way, PM may promote adverse cardiovascular effects such as endothelial
dysfunction, atherosclerosis and thrombosis. Circulating PM or soluble PM  components also have
the potential to impact other organ systems. However, convincing evidence that this occurs to an
appreciable extent in healthy individuals following inhalation of PM at concentrations relevant to
ambient exposures is lacking.



5.5. Disease  of the Cardiovascular and Other Organ

Systems

      As discussed above, deposition of PM in the lung may lead not only to pulmonary disease but
also to diseases of other systems (Figure 5-5). In the  cardiovascular system,  myocardial ischemia and
MI may occur as a result of the above proposed effects of PM on atherosclerosis, plaque instability,
thrombosis, plaque rupture and/or altered vasoreactivity of coronary vessels. Myocardial ischemia
and MI may  alter the conduction and depolarization properties of the heart and lead to arrhythmic
events. In addition, thrombosis may lead to stroke and/or thromboembolic disease. Many of these
processes may be  interlinked and responses to ambient PM exposures may involve multiple
mechanisms simultaneously with some variability depending on PM composition. Furthermore, it is
not clear at this time whether PM initiates cardiovascular disease or whether it perturbs existing
disease.
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      In addition, recent studies which are discussed in later chapters have demonstrated PM-
dependent effects on the CNS (Campbell et al., 2005, 087217; Kleinman et al, 2008, 190074;
Sirivelu et al., 2006, 111151; Veronesi et al., 2005, 087481; Win-Shwe et al., 2008, 190146). At this
time, it is not known whether this is a direct or indirect consequence of PM exposure. Translocation
of soluble and poorly soluble particles from the olfactory mucosa via the axons to the olfactory bulb
of the brain has been proposed as a possible mechanism by which PM or its components may
directly access the CNS. Evidence for this pathway is discussed in Section 4.3.3.2. Alternative
mechanisms proposed for PM-mediated CNS effects involve systemic inflammation and autonomic
responses. These are new and intriguing possibilities which warrant further investigation.
      PM-dependent effects on the reproductive system, reproductive outcomes and perinatal
development have also been identified and are discussed in a later chapter. Mechanisms involved in
these responses have not been determined. However, it seems possible that systemic inflammation
and/or oxidative stress may play a role. Developmental windows of susceptibility may also be an
important consideration. Furthermore, it has been hypothesized that oxygen gradients and redox
status are key to cell differentiation and epigenetic processes occurring during development
(Section 5.1.11) (Hitchler and Domann, 2007, 191151).



5.6.  Acute  and  Chronic  Responses

      In general, repeated acute responses may lead to cumulative effects which manifest as chronic
disease. Several examples relevant to the modes of action discussed in this chapter are that of
allergic responses, atherosclerosis and lung development. Allergic responses require repeated
exposures to antigen over time. Co-exposure to an adjuvant, possibly DEP or ultrafme concentrated
ambient particles (CAPs), can enhance this response. Furthermore,  the presence of oxidative stress,
as may occur in response to PM, can contribute to allergic responses. Allergic sensitization often
underlies allergic asthma, characterized by inflammation and AHR. In this way, repeated or chronic
exposures involving multifactorial responses (immune system activation, oxidative stress,
inflammation) can lead to irreversible outcomes. Similarly, the development of atherosclerosis
involves inflammation and remodeling of the blood vessel wall. Factors contributing to this process
include systemic inflammation, endothelial dysfunction, oxidative stress and high levels of
circulating lipids. PM exposure is associated with three out of four  of these processes. The role of
PM in initiating, promoting or complicating this disease or its outcomes has yet to be determined.
Critical windows of susceptibility during development also provide an opportunity for repeated
exposures to injurious agents to lead to irreversible changes in organ structure and function. The
extended period of postnatal lung development in humans and other species heightens this
vulnerability. PM may serve as such  an injurious agent as has been  demonstrated previously for
hyperoxia (Randell et al., 1990, 191956).
      Furthermore, adverse outcomes may be precipitated by acute events superimposed on chronic
disease states. In the case of allergic  asthma, acute PM exposure may provoke asthmatic responses
through oxidative stress and inflammatory pathways. Additionally,  PM can act as  a carrier of
aeroallergens and other biological materials which can potentially trigger asthma attacks. Similarly,
PM exposure may  provoke inflammatory or thrombotic responses leading to rupture of an
atherosclerotic plaque which subsequently results in acute MI. In this way, the outcome of an acute
exposure to PM may be drastically worsened by the underlying chronic disease.



5.7.  Results of New Inhalation Studies  which Contribute

to Modes of Action

      Prior to this  review, much of the evidence for the proposed modes of action was obtained from
animal studies involving IT instillation or inhalation of high concentrations of PM and from cell
culture experiments. In many cases, the types of PM used were of questionable relevance to ambient
exposures (i.e., high concentrations of ROFA, metals and ambient PM collected on filters). Since
then, many inhalation studies have been conducted using CAPs, combustion-derived PM, urban air
December 2009                                 5-19

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and carbon black, generally using concentrations of PM lower than 1 mg/m3. Much of this research
has been conducted in animal models of disease. These key new studies, described in detail in
Chapters 6 and 7, add to the understanding of modes of action which are relevant to ambient PM
exposure. A compilation of pertinent results is found below.

       •   Altered lung function including changes in respiratory frequency and AHR following
           short-term exposures to CAPs and combustion-derived PM (Section 6.3.2.3)

       •   Mild pulmonary inflammation in response to short-term exposures to CAPs, urban air,
           combustion-derived PM and carbon black (Section 6.3.3.3)

       •   Mild pulmonary injury in response to short-term exposure to CAPs and combustion-
           derived PM (Section 6.3.5.3)

       •   Inhibition of cell proliferation in the proximal alveolar region of neonatal animals
           following short-term exposure to iron-soot (Section 6.3.5.3)

       •   Pulmonary oxidative stress in response to short-term exposure to CAPs, urban air,
           combustion-derived PM, carbon black and iron-soot; pulmonary nitrosative stress in
           response to titanium dioxide (TiO2) (Section 6.3.4.2)

       •   Antioxidant intervention which ameliorates PM effects on oxidative stress, allergic
           responses, and AHR (Sections 6.3.4.2 )

       •   Allergic sensitization and exacerbation of allergic responses in response to CAPs and
           combustion-derived PM (Section 6.3.6.3)

       •   Altered methylation of promoter regions of IFN-y and IL-4 genes suggestive of pro-
           allergic Th2 gene activation following short-term exposure to combustion-derived PM in
           an allergy model (Section 6.3.6.3)

       •   Increased susceptibility to respiratory infection following exposure to combustion-
           derived PM (Section 6.3.7.2)

       •   Effects on nasal epithelial mucosubstances, airway morphology  and airway
           mucosubstances following chronic exposure to urban air-derived PM and woodsmoke
           (Section 7.3.5.1)

       •   Worsening of papain-induced emphysema following chronic exposure to urban air-
           derived PM (Section 7.3.5.1)

       •   Effects on lung development following chronic exposure to urban air-derived PM
           (Sections 7.3.2.2 and 7.3.5.1)

       •   Prolonged exposure to CAPs and combustion-derived PM leading sometimes to mild
           pulmonary inflammation, oxidative stress and injury and sometimes to loss of
           inflammatory, oxidative stress and AHR responses which were observed after short-term
           exposures (Sections 7.3.2.2, 7.3.3.2, 7.3.4.1, 7.3.5.1 and 7.3.6.2)

       •   Hypermethylation of lung DNA following chronic exposure to combustion-derived PM
           (Section 7.3.5.1)

       •   A role for TRPV1 irritant receptors in activating local axon and  CNS reflexes following
           short-term exposure to CAPs and combustion-derived  PM (Section 6.2.9.3)
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           A role for TRPV1 irritant receptors in mediating lung and heart oxidative stress through
           increased parasympathetic and sympathetic activity in response to CAPs
           (Sections 6.2.9.3 and 6.3.4.2)

           Altered heart rate variability in response to CAPs, combustion-derived PM and carbon
           black (Section 6.2.1.3)

           Arrhymthmic events in response to CAPs and combustion-derived PM (Section 6.2.2.2)

           Altered cardiac contractility following short-term exposure to CAPs and carbon black
           (Section 6.2.6.1)

           Enhanced myocardial ischemia following short-term exposure to CAPs (Section 6.2.3.3)

           Endothelial dysfunction and altered vascular reactivity following short-term exposure to
           CAPs, combustion-derived PM and TiO2 (Section 6.2.4.3)

           Increases in blood pressure following short-term exposure to CAPs and carbon black
           (Section 6.2.5.3)

           Changes in blood leukocyte counts following short-term exposure to CAPs and carbon
           black (Section 6.2.7.3)

           Increased levels of blood coagulation factors following short-term exposure to CAPs and
           on-road highway aerosols (Section 6.2.8.3)

           Systemic and cardiovascular oxidative stress in response to short-term exposure to CAPs,
           road dust and combustion-derived PM (Section 6.2.9.3)

           Progression of atherosclerosis, induction of TF in aortic plaques, vascular oxidative
           stress and altered vasomotor function following long-term exposure to CAPs in a
           susceptible animal model (Section 7.2.1.2)

           Vascular remodeling following chronic exposure to urban air-derived PM
           (Section 7.2.1.2).

           Enhanced angiotensin II-induced hypertension accompanied by vascular oxidative stress
           and altered vasoreactivity in response to chronic exposure to CAPs (Section 7.2.5.2)

           Exaggerated insulin resistance, visceral adiposity and systemic inflammation in response
           to chronic exposure to CAPs and a high-fat diet (Section 7.2.3.1)

           CNS responses following short- and long-term exposures to CAPs and combustion-
           derived PM (Section 6.4.3)

           Effects on the reproductive system, reproductive outcomes and developmental outcomes
           following chronic exposure to urban-air derived PM (Section 7.4.2)

           DNA adducts in nose, lung and liver following chronic exposure to urban air
           (Section 7.5.2.1)

           Germ line mutations, DNA strand breaks and global hypermethylation in sperm
           following chronic exposure to urban air-derived PM (Section 7.5.3)
December 2009                                  5-21

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5.8.  Gaps in Knowledge
      The new studies highlighted in Section 5.7 confirm and extend findings from older studies.
However, this increasing body of evidence does not provide a complete picture of the biological
pathways involved in mediating PM effects. For example, a lack of information regarding the time-
dependence of many responses makes it difficult to understand the underlying biological
mechanisms. Existing gaps in knowledge include:

       •  The spatial distribution of retained particles in the lung and its impact

       •  The deposition, uptake and clearance of UFPs in the lung

       •  Effects of ambient PM exposures on epithelial barrier function in the lung

       •  Time dependence of responses

       •  The putative modulation of neural reflexes by pre-existing disease or other factors

       •  The putative role of neural reflexes besides those involving pulmonary irritant receptors

       •  The putative role of ET in altering vasomotor tone following PM exposure

       •  The putative translocation of PM or soluble components across the epithelial barrier of
          the lung into the circulation

       •  The putative translocation of PM from olfactory epithelium to the olfactory bulb and
          other brain regions

      Additional studies will be required to clarify the biological  mechanisms underlying the health
effects of PM.
December 2009                                  5-22

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             Chapter 6.  Integrated  Health  Effects
                     of Short-Term  PM Exposure
6.1.  Introduction

      This chapter reviews, summarizes, and integrates the evidence of relationships between short-
term exposures to PM and a variety of health-related outcomes and endpoints. Cardiovascular and
respiratory health effects of short-term exposure to various size fractions and sources of PM have
been examined in numerous epidemiologic, controlled human exposure and toxicological studies. In
addition, there is a large body of literature evaluating the relationship between mortality and short-
term exposure to PM. The association between PM exposure and central nervous system function
has also been assessed, although far fewer studies are available. The research approaches used to
evaluate health effects of PM exposure are described in Section 1.5 along with advantages and
limitations of the various study types. Chapter 5 provides an overview of the potential
pathophysiological pathways and modes of action underlying the PM-induced health effects
observed in animal and human studies. Evidence from the scientific literature of specific
cardiovascular and systemic effects, respiratory effects, and central nervous system (CNS) effects
associated with exposure to PM are presented in Sections 6.2, 6.3, and 6.4, respectively. Evidence of
associations between short-term exposure to PM and mortality are described in Section 6.5. The
chapter concludes with an evaluation of PM-induced health effects attributable to specific
constituents or sources (Section 6.6). More detailed descriptions of each study evaluated for this
assessment  are presented in Annexes C, D, E, and F.
      Findings for cardiovascular and respiratory effects are presented by specific endpoint or
measure of effect, leading from more subtle health outcome measures (e.g., heart rate variability
[HRV]) to the more severe, such as hospitalization and mortality for cardiovascular disease.
Conclusions from the 2004 PM AQCD (U.S. EPA, 2004, 056905) are briefly  summarized at the
beginning of each section, and the evaluation of evidence from recent studies builds upon what was
available during the previous review. For each health outcome, results  are summarized for studies
from the specific scientific discipline, i.e., epidemiologic, controlled human exposure, and
toxicological studies. The sections conclude with summaries of the evidence on the various health
outcomes and integration of the findings that leads to conclusions regarding causality based  upon the
framework  described in Chapter 1. Determination of causality is made for the overall health effect
category, such as cardiovascular effects, with coherence,  consistency and biological plausibility
being based upon the evidence from across disciplines and also across  the suite of related health
outcomes ranging from the more subtle health outcomes to cause-specific mortality.  In the summary
sections for cardiovascular and respiratory effects and all-cause mortality, the evidence is
summarized and independent conclusions drawn for relationships with PM2.5, PMi0_2.5, and ultrafine
particles (UFPs) (Sections 6.2.12, 6.3.10, and 6.5.3, respectively). Evidence of central nervous
system effects is also divided by scientific discipline; however, the lack of data does not allow for
informative summaries of effect by PM metric in discussing CNS effects (Section 6.4.4).
 Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
 Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
 developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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6.2.  Cardiovascular and Systemic Effects
6.2.1.  Heart Rate and  Heart Rate Variability

      Heart rate (HR), HRV, and BP are all regulated, in part, by the sympathetic and
parasympathetic nervous systems. Changes in one or more may increase the risk of cardiovascular
events (e.g., arrhythmias, MI, etc.). Decreases in HRV have been associated with cardiovascular
mortality/morbidity in older adults and those with significant heart disease (TFESC, 1996, 003061).
In addition, decreased HRV may precede some clinically important arrhythmias, such as atrial
fibrillation, as well as sudden cardiac death, in high risk populations (Chen and Tan, 2007, 197461;
Sandercock and Brodie, 2006, 197465; Thong  and Raitt, 2007, 197462).
      HRV is measured using electrocardiograms (ECG) and can be analyzed in the time domain
(e.g., standard deviation of all NN intervals [SDNN], square root of the mean squared successive NN
interval differences [rMSSD]), and/or the frequency domain measured by power spectral analysis
(e.g., high frequency [HF], low frequency [LF], ratio of LF to HF [LF/HF]). SDNN generally
reflects the overall modulation of HR by  the autonomic nervous system (ANS), whereas rMSSD and
frequency  variations in HR generally reflect parasympathetic activity. Thus, rMSSD is generally well
correlated  with HF, which also reflects the parasympathetic modulation of HR.  LF is predominately
determined by both sympathetic parasympathetic tone and increased LF/HF indicates
sympathoexcitation, which correlates with decreased overall HRV (SDNN, rMSSD). Thus LF/HF is
thought to estimate the ratio of sympathetic influences on HR to parasympathetic influences.
      While HRV is commonly described as being a reflection of vagal and adrenergic input to the
heart, there is clearly a more complex phenomenon reflected in HRV parameters. Rowan et al. (2007,
191911) provide a review of HRV and its use and interpretation with respect to  air pollution studies.
To summarize, HRV indices are excellent measures of extrapulmonary effects from inhaled
pollutants, but the characterization of the acute, reversible responses to air pollution as being either
parasympathetic or sympathetic in origin, much less predictive of some adverse outcomes such as
ventricular arrhythmia, is relatively unsupported by the clinical literature. This is consistent with the
2004 PM AQCD (U.S. EPA, 2004, 056905) which  stated that there is inherent variability in the
minute-to-minute  spectral measurements, but long-term HRV measures demonstrate excellent
day-to-day reproducibility.
      The 2004 PM AQCD (U.S. EPA, 2004, 056905) presented limited evidence of PM-induced
changes in HRV. However, findings from epidemiologic, controlled human exposure and
toxicological studies demonstrated both decreases and increases in HRV following PM exposure.
Recent epidemiologic studies have demonstrated a more consistent decrease in  HRV (SDNN and
rMSSD), which is supported by several controlled human exposure studies published since 2003. In
these studies, decreases in HRV were observed among healthy adults following short-term exposures
to PM2.5 and PMi0_2.5 CAPs. It is interesting to note that these effects were not observed in adults
with asthma or COPD. The effect of PM  on HRV observed in animal toxicological studies continues
to vary greatly, which may be due in part to strain differences in baseline HRV.


6.2.1.1.   Epidemiologic Studies

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) reviewed several  studies of PM exposure and
HR or HRV and described mixed findings across studies.  Several additional studies have
investigated the association between acute changes in multiple HRV parameters and ambient air
pollutant concentrations in the U.S., Canada, Europe, Mexico, and Asia.  Features and results of these
studies are presented in Table 6-1, and are summarized below.
      In a multicity study, Liao and colleagues (2004, 056590) used data from the  fourth cohort
evaluation of the Atherosclerosis Risk in  Communities (ARIC)  Study (1996-1998). The 6,784
subjects were 45-64 yr of age and lived in Washington County, MD, Forsyth County, NC, or the
suburbs of Minneapolis, MN. Linear regression models were used to examine the change in HRV
associated with PMi0, O3, SO2, CO, and NO2 concentrations in the  1-3 days prior to ECG
measurement. Among all subjects, each 11.5 (ig/m3 increase in mean daily PMi0 concentration 1 day
before the  ECG measurement was associated with a 0.06 ms2 decrease in log-transformed HF (95%
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CI: -0.10 to -0.02) and a 1.03 ms decrease in SDNN (95% CI: -1.64 to -0.42). A smaller
non-significant decrease was also observed for log transformed LF. This reduction in cardiac
autonomic control was larger among hypertensive subjects, suggesting that this group may be
susceptible to the effects of PM.
      In a study of randomly selected participants in the Women's Health Initiative (WHI), a
multicity U.S.  study, Whitsel et al. (2009,  191980) found decreases in rMMSD and SDNN in
association with PM10 concentration. The associations were stronger among participants with
diabetes. For example, in subjects with impaired fasting glucose, the reduction in rMSSD was 8.3%
(-13.9, -2.4)  among those with high levels of insulin and 0.6% (-2.1, 1.6) among those with low
levels of insulin.  Similar results  were observed comparing high and low levels of insulin resistance.
      Timonen et al. (2006, 088747) conducted a multicity panel study of elderly  subjects with
stable coronary heart disease who lived in 3 European cities (Amsterdam, the Netherlands; Erfurt,
Germany; or Helsinki, Finland). They collected ECGs biweekly for six months in each subject. This
analysis, done as part of the ULTRA Study, examined changes in HRV (resting, paced breathing,
supine, and 5-min beat-to-beat NN intervals) associated with changes in fixed monitor particulate
concentrations (PM2.5, PMi0_2.5) with an emphasis on counts of UFPs (0.01-0.1 (im particles) and
accumulation mode particles (ACP; 0.1-1.0 (im particles). Mixed models were first fit to estimate the
change in HRV associated with PM (UFP, ACP, PM2.5, and PMi0_2.s) concentrations on the same and
previous 4 days in each city. In pooled analyses, the most consistent results identified were for
LF/HF (Table 6-1). Estimates for PM2.5, however,  differed across cities. PM2.5 was associated with
decreased HF power and increased LF/HF in Helsinki, increased HF power and decreased LF/HF in
Erfurt, and not associated with any HRV metric in Amsterdam. In a subsequent analysis, de Hartog
et al. (2009,  191904) investigated whether exposure misclassification, effect modification by
medication use, or particle composition differences across the three cities could explain the result
observed. These authors found that PM2.5 apportioned from traffic, long-range transported PM2.5 and
outdoor PM2 5 were associated with reduced HRV most strongly among those not taking beta-
blockers (Table 6-1). Indoor and personal PM25 were not associated with decreased HRV in this
study. Therefore, the authors concluded that effect modification by medication use and particle
composition differences across the three cities may, in part, explain the heterogeneous PM2 5 findings
in the previous analysis.
      The association between HRV and short-term increases in PM2 5, PM10_2.5, PM10, other size
fractions and components was also examined in single-city studies conducted in the U.S. or Canada
(Table 6-1). Among U.S. and Canadian cities, increases in PM25 were generally associated with
decreased SDNN and/or decreased HF power but not in all studies. However, studies also reported
increased SDNN associated with PM25 concentrations (Riediker  et al., 2004, 056992; Wheeler et
al., 2006, 088453). In addition, Yeatts et al. (2007, 091266) reported increased rMSSD and HF
power with increased PM25 concentrations as well as SDANN5 (standard deviation of the average of
normal to normal intervals in all 5-min intervals in a 24-h period), and SDNN24HR (standard
deviation of the average of all normal to normal intervals in a 24-h period).
      Other  size  fractions (e.g. coarse PM and UFPs) were also associated with decreases in HRV
metrics in several single-city studies conducted  in the U.S. or Canada. Lipsett et al. (2006, 088753)
reported significantly decreased SDNN associated with increases in 2- and 6-h mean PMi0 and
PM10_2.5 concentrations. Yeatts et al. (2007, 091266) reported decreased rMSSD, SDNN24HR,
SDANN5, ASDNN5 (mean of the standard deviation in all 5-min segments of a 24-h recording),
proportion of NN intervals <50 m apart (pNN50) (7 min and  24 h), and HF power associated with
increased PMi0_25 concentration. Of those studies examining  HRV associations with particle counts
(Adar  et al., 2007, 001458: Park et al., 2005, 057331). only  Adar et al. (2007, 001458) found clear
evidence of such effects (e.g., decreased SDNN, LF, HF). Decreased HRV was also associated with
increases in ambient mean  SO42~ concentration (Luttmann-Gibson et al., 2006, 089794). ambient
mean BC concentration (Park et al., 2005, 057331; Schwartz et al., 2005, 074317). and traffic
generated particles/pollution (Adar  et al.,  2007, 001458; Riediker et al., 2004, 056992) in these
single-city studies.
      Studies in Asia, Europe, and Mexico have also reported decreases in one or several HRV
metrics (Table 6-1) associated with increases in PM25 concentration or other size fractions. However,
a study conducted in Scotland reported no PM-HRV associations (Barclay et al., 2009, 179935).
Riojas-Rodriguez et al.  (2006, 156913) reported significantly decreased LF and HF power associated
with each 1 ppm increase in CO concentration, but only small non-significant decreases associated
with PM2.5.
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      Summary of Epidemiologic Studies of Heart Rate and HRV

      HRV studies investigated lagged pollutant concentrations from 2 h-5 days before ECG
measurement, reporting effects associated with mean pollutant concentrations lagged as short as
1-2 h, and more consistently with lags of 24-48 h. Taken together, these international and
U.S./Canadian studies show decreases in HRV associated with PM25 in most studies that use SDNN,
rMSSD or HF power. The effects of PMi0_2.5, UFPs, and components were evaluated in fewer studies
but associations with decreased HRV (e.g., both time and frequency measures) were observed. PMi0
studies also found evidence for PM-induced alterations in HRV, however, it is difficult to determine
which size fraction of PMi0 (e.g., PMi0_2.5, PM25 or UFPs) imparts the effects observed. As a result,
PM10 studies provide supportive evidence for the overall effect of PM on HRV, but not for a specific
size fraction. The proportion of studies reporting decreases in HRV may be inflated by publication
bias (i.e., studies showing little or no effects are not submitted for publication).


      HRV Studies Investigating Specific Mechanisms

      Panel studies investigating PM-HRV associations have also been useful in investigating
potential mechanistic pathways by which PM may elicit a cardiovascular response. A series of
analyses using data from the Normative Aging Study, a cohort of older men living in the Boston
metropolitan area, has also provided mechanistic insights into the PM-HRV association (Baccarelli
et al, 2008, 191959: Chahine  et al, 2007, 156327: Park et al, 2005, 057331: Park et al, 2006,
091245: Park et al., 2008, 156845: Schwartz  et al., 2005, 086296).
      Park et al. (2005, 057331) studied the association between short-term increases in ambient air
pollution and changes in HRV using males enrolled in the Normative Aging Study. Using linear
regression models, the association between HRV metrics and PM2.5, O3, NO2, SO2, CO, BC, and
particle number count (PNC) moving averages (ma)  in the previous 4, 24, and 48 h were examined.
The modifying effects of hypertension, diabetes, ischemic heart disease (IHD), and use of
hypertensive medications were also estimated. Of the pollutants examined, only PM25 and O3 were
associated with reductions in HRV, and each pollutant's effect appeared independent of the other.
Each 8 (ig/m3 increase in mean PM25 concentration in the previous 48 h was associated with a 20.8%
decrease in HF power (95% CI: -34.2 to -4.6), with larger effects among subjects with hypertension,
IHD, and diabetes. The authors state that since BC concentrations were also associated with adverse
changes in HRV, this suggests that traffic pollution may be partially responsible for the HRV
changes.
      Schwartz et al. (2005, 086296) examined the hypothesis that adverse changes in HRV due to
PM2 5 are mediated by an oxidative stress response among participants in the Normative Aging
Study. They examined whether the change in HF power associated with each 10 (ig/m3 increase in
48-h mean PM25 was modified by the presence or absence of the allele for glutathione S-transferase
Ml (GSTM1), use of statins, obesity, high neutrophil counts, higher blood pressure (BP), and/or
older age. In subjects without the GSTM1 allele and its protection against oxidative stress, each
10 (ig/m3 increase in 48-h mean PM25 concentration was associated with a 34%  decrease in HF
power (95% CI: -52 to -9). There was no association among those with at least one copy of the
allele. Obesity and high neutrophil counts also worsened the effect of PM on HRV regardless of
allele.
      Park et al. (2006, 091245) investigated whether transition metals may be responsible for
cardiorespiratory effects that are observed in association with PM2 5. Again using the Normative
Aging Study cohort, they investigated whether subjects with two hemochromatosis (HFE)
polymorphisms associated with increased iron uptake had a smaller decrease in HF power associated
with PM than those subjects without either variant. Each 10 (ig/m3 increase in 48-h mean PM25 was
associated with a 31.7% decrease in HF (95% CI: -48.1 to -10.3) among subjects without either
polymorphism, but not among those with the 2 protective HFE alleles.
      Chahine et al. (2007, 156327) reported a 10.5% reduction in SDNN (95% CI: -18.2 to -2.2)
associated with each 10 (ig/m3 increase in the mean 48-h PM25 concentration among Normative
Aging Study participants without the GSTM1 allele, but only a 2.0% SDNN decrease
(95% CI: -11.3, 8.3) in those with the allele. This supports the PM-HF power findings of Schwartz
et al. (2005, 086296). Further, subjects with the long repeat polymorphism in the HO-1 promoter had
a greater decline in SDNN associated with each 10 (ig/m3 increase in the mean 48-h PM25
December 2009                                  6-4

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concentration (-8.5% [95% CI: -14.8 to -1.8) than those with the short repeat polymorphism in HO-1
(7.4 % increase [95% CI: -8.7 to 26.2). Again, this suggests that PM-HRV changes are mediated, in
part, by oxidative stress.
      Baccarelli et al. (2008, 191959) investigated whether the PM2.5-HRV association was modified
by dietary intakes of methyl nutrients (folate, vitamins B6 and B12, and methionine) and related
gene polymorphisms thought to either confer increased or decreased risk of CVD among men
enrolled in the Normative Aging Study. Each 10 (ig/m3 increase in PM2 5 in the previous 48 h was
associated with -8.8% (95% CI: -16.7 to -0.2) and -11.8% (95% CI: -20.8 to -1.8) decreases in
SDNN, among those with CC/TT genotypes of the C677T methylenetetrahydrofolate reductase
(MTHFR) polymorphism, and the CC genotype  of the C1420T cytoplasmic serine
nydroxymethyltransferase (cSHMT) polymorphism, respectively. There were no changes among
those with CC MTHFR and CC/TT cSHMT. Further, there were similar HRV reductions in those
subjects with lower intakes of B6, B12, and/or methionine, but no decreases in those with high
intakes. Thus these genetic and nutritional variations in the methionine cycle may modify the PM-
HRV association.
      Finally, among those Normative Aging Study subjects with high chronic lead exposure as
measured using X-ray fluorescence of the tibia, each 7 (ig/m3  increase in mean PM2.5 concentration
in the previous 48 h  was associated with a 22% decrease in HF power (95% CI: -37.4 to -1.7) (Park
et al., 2008, 093027). Decreases in HF HRV were also associated with each 2.5 (ig/m3 increase in
mean SO42~ concentration in the previous 48 h (22% decrease [95% CI: -40.4 to 1.6). The authors
suggest that these findings are consistent with an oxidative stress response. Although this series of
studies suggest a role of oxidative stress and perhaps methyl nutrients and related polymorphisms in
these short-term associations of PM2.5 with HRV, replication by  other investigators in other cities and
in other populations  will aid interpretations  of these findings.
      Using data from a randomized controlled trial in Mexico City, Romieu et al. (2005, 086297)
investigated whether omega-3 fatty acids in fish oil supplements would mitigate the adverse effects
of acute PM exposure on HRV. Residents of a Mexico City nursing home were randomized to either
2 g/day offish oil or 2 g/day of soy oil. They used random-effects regression models to estimate the
change in HRV associated with mean PM2 5 concentration in the pre-supplementation and
supplementation phases. In the group receiving the fish oil supplement, each 8 (ig/m3 increase in 24-
h mean total PM25 exposure (weighted average of indoor and outdoor PM25 based on time activity
diaries) was  associated with a 54% reduction (95% CI: -72 to -24) in log transformed HF power in
the pre-supplementation phase. However, in the  supplementation phase of the trial, each 8  (ig/m3
increase in 24-h mean total PM2 5 concentration was associated with only a 7% reduction in log
transformed HF power (95% CI: -20 to 7). Decreases  in other HRV parameters associated with PM25
were also muted in the supplementation phase. In the group receiving the soy oil supplement, the
reduction in HF power was also smaller in magnitude during the supplementation phase. However,
among those receiving the soy oil supplement, the differences between the pre-supplementation
PM2 5-HF change and the supplementation PM2 5-HF change were smaller compared to those
receiving the fish oil, and were not statistically significant. Romieu et al. (2008, 156922)also report
that omega-3 polyunsaturated fatty acids appear to modulate the adverse effect of PM25 based on
measured biomarkers of oxidative response (Section 6.2.9.1).
      Summary of HRV Studies Investigating Specific Mechanisms

      In summary, several analyses of data from the Normative Aging Study have provided evidence
that effect of PM25 on HRV is modulated by genetic polymorphisms related to oxidative stress
(Chahine  et al., 2007, 156327; Park  et al., 2006, 091245; Schwartz et al., 2005, 086296) or dietary
methyl nutrients or related genetic polymorphisms (Baccarelli  et al., 2008, 191959). In addition,
preexisting conditions such as diabetes, IHD, and hypertension (Park et al., 2005, 057331; Whitsel
et al., 2009, 191980). beta-blocker use (Folino  et al., 2009, 191902; Park et al., 2005, 057331).
chronic lead exposure (Park et al., 2008, 093027) and omega-3 fatty acid (Romieu  et al., 2005,
086297) are reported to modulate the effect of PM25 on HRV.
December 2009                                 6-5

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Table 6-1.

Characteristics of epidemiologic studies investigating associations between PM and
changes in HRV.
PM Type, Exposure
Lag
Study Subjects
Ambient Concentration Recording CRMM i c HF,
(ug/m3)* Length SDNN LF rMSSD
LF/HF
MUL77C/rYSrUD/ES
Liao et al. (2004,
056590)
Whitsel et al.
(2009, 1919801
Timonen et al.
(2006, 0887471
De Hartog et al.
(2009, 1919041
PM,o, 24-h, lag 1-day
PM10, 24-h, 3-d avg
within 5 days preceding
exam
UFP, lags 0-2 days
AC, lags 0-2 days
PM25, lags 0-2 days
PM10.25, 2-day lag
24 h PM25 outdoor, PM25
traffic, long-range
transported PM25
N=6784 (mean age = 62 yrs),
ARIC study: MD, NC, MN
N=4295 randomly selected
participants in the WHI Trial
Stable IHD patients (65+ yr)
Amsterdam, Netherlands
(N=37)
Erfurt, Germany (N=47)
- Helsinki, Finland (N=47)
Stable IHD patients (65+)
Amsterdam, Netherlands
(N=37)
Erfurt, Germany (N=47)
Helsinki, Finland (N=47)
(Effects strongest among those
NOT taking beta-blockers)
24.3 5-min [ I I
28 visit 1
27 visit 2 10 second [ I
27 visit 3
Amsterdam:
17,300 particles/cm3
Erfurt:
21, 100 particles/cm3 i T
Helsinki:
17,000 particles/cm3
Amsterdam:
21 00 particles/cm3 5-min
Erfurt: (Pooled
1800 particles/cm3 estimates ^ 1
,,,.,. during paced
Helslnkl: 3 breathing
1400 particles/cm presented to
Amsterdam: 20.0 Inerl9n"
Erfurt: 23.1 [ t
Helsinki: 12.7
Amsterdam: 15.3
Erfurt: 3.7
Helsinki: 6.7
Median Outdoor:
Amsterdam: 16.7
5min I I
Erfurt: 16.3
Helsinki: 10.6


1
1
1
1

U.S. AND CANADIAN STUDIES
Park etal. (2005,
0573311
Riediker et al.
(2004, 056992)
Schwartz et al.
(2005, 0743171
Yeatts et al. (2007,
0912661
PM25, 48-h avg
PNC, 48-h avg
BC, 48-h avg
In-vehicle PM25 (mass)
9-h avg
BC, 24-h
PM25, 24-h
Secondary PM
(estimated), 1-h
PM,o.2.5, 24-h
PM25,24-h
N=497 men (mean age = 73
yr), Normative Aging Study
Boston, MA
N=9 healthy state police
N=28 older adults (61 -89 yr),
- 1 2 wk follow-up, Boston, MA
N=12 adult asthmatics, Chapel
Hill, NC
24-h: 11. 4
98th: 30.58
24-h: 28, 942 (13, 527) 4-min
particles/cm3
24-h: 0.92 [ [ [
9-h in-vehicle: 23 10-min t ~» t
24-h Median: 1.0 [ I
24-h Median: 10 23.mjn 1 |
1-h Median: -1.7 [ I
24-h: 5.3 [ [ [
24-h: 12.5 t 1 t
t
i
r
i
r
r
r


December 2009
6-6

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Wheeler et al.
(2006, 0884531
Dales 2004 (2004,
099036)
Luttmann-Gibson
et al. (2006,
0897941
Adaretal. (2007,
0014581
Pope et al. (2004,
055238)
Sullivan et al.
(2005, 1094181
Lipsett et al. (2006,
0887531
Ebelt et al. (2005,
0569071
Baccarelli et al.
(2008, 1919591
Fan et al. (2008,
1919791
PM Type, Exposure
Lag
PM25, 4-h avg
PM25, 4-h avg
EC, 4-h avg
EC, 4-h avg
PM25, 24-h avg
(personal)
PM25, lag 1-day
Sulfate, lag 1-day
Nonsulfate PM, lag 1-day
EC, lag 1-day
PM25, 24-h avg
BC, 24-h avg
PNC fine
PNC course
PM25(FRM), 24-h, lag
1-day
PM25, 1,2, 24-h avg
PM,0,
PM,0-2.5
PM25
PM10, 24 h
PM,0-2.5
PM25, 24-h
PM25 Sulfate, 24-h
outdoor
PM25, 48 h
PM2 5 personal, 1 h
Study Subjects
N=18 COPD, Atlanta, GA
N=1 2 Ml, Atlanta, GA
N= 18 COPD, Atlanta, GA
N=1 2 Ml, Atlanta, GA
N=36 IHD patients, Toronto,
Canada
N=32 (65+ yr)
Steubenville, OH
N=44 (60+ yr), diesel bus riders
St. Louis, MO
N=88 (65+ yr; 250 p-days),
Utah Valley
N=21 (65+ yr) with CVD,
Seattle WA
N=13 (65+ yr) w/out CVD,
Seattle WA
N=19IHD (65+yr), 12wkfu,
Coachella Valley, CA
N=16COPD, Vancouver,
Canada
N=549 Normative Aging Study
and residents of Boston
metropolitan area
N=11 crossing guards in New
Jersey
Ambient Concentration
(ug/m3)*
4-h: 17.8
• 4-h: 2.3
24-h personal: 19.9
24-h: 19.7
24-h: 6.9
24-h: 10.0
24-h: 1.1
24-h: 10.17
98th: 22. 43
330 ng/m3
42 particles/cm3
0.02 particles/cm3
23.7
• Median:10.7
31.0 and 46.1
None given
14 and 23. 2
17
5.6
11.4
98th: 23
2.0
Geometric mean (95%
confidence interval)
10.5(10.0,10.9)
Only change in 1-h PM25
reported
Morning shift: 35.2
Afternoon shift: 24.1
Recording CRMM i c HF,
Length SDNN LF rMSSD
t t t
on-min
r
i
Not described -> -> ->
1 1 1

1 1 1
r i
i i i
5-min III
1 1 1
r r r
24-h 1 |


5-min III
domain; 2-h, 1 1 ->
24-h Time
domain lit
1 1
r
24-h i i
i
7min I
24 h |
LF/HF
r
i


->




r
r
r
i












INTERNATIONAL STUDIES
Chan et al. (2004,
0873981
Chuang et al.
(2005, 0879891
NCo.02-1, 1-4 h
PMi.o-o.3, 1-4 h
PM2.5-i.o, 1-4 h
PM,o.2.5, 1-4 h
N=9 adults (1 9-29 yr) with lung
function impairment, Taipei,
Taiwan
N=10 adults (42-79 yr) with
lung function impairment,
Taipei, Taiwan
N=16, Patients with IHD/
hypertension , Taipei, Taiwan
23,407(19,836)
particles/cm
25,529 (20,783)
particles/cm3
37.2
12.6
14.0
1 1 1
1 1 1
5-min III
1 1 1
1 1 1
i
i
r
r
r
December 2009
6-7

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Holguin et al.
(2003, 0573261
Romieu et al.
(2005, 0862971
Riojas-Rodriguez
et al. (2006,
156913)
Barclay et al.
(2009, 1799351
Cardenas et al.
(2008, 1919001
Folino et al. (2009,
1919021
Min et al. (2008,
1919011
PM Type, Exposure
Lag
PM,,-o.3, 1-4 h
PM2.5-i.o, 1-4 h
PM,0-2.5, 1-4 h
PM25, 24-h
P M2 .5, 24-h (outdoor and
indoor)
Personal PM25
PM10, daily
PNC, daily
Estimated PM25 and PNC
PM25-outdoor
PM25-indoor
PM10,24h
PM25,24h
PM025,24h
PM,o, 12 h
Study Subjects
N=10 IHD, Taipei, Taiwan
N=21 without hypertension
(60-96 yr), Mexico City
N=13with hypertension (60-88
yr), Mexico City
N=50 nursing home residents
65+ yr, Mexico City
N=30 IHD patients, Mexico City
N=132, stable coronary heart
failure
Aberdeen, Scotland
N=52 (31 women, 21 men; 20-
40 yr), southeast of Mexico City
N=39 (36 male, 3 female;
mean age = 60 yr)
Padua, Italy
N=1349 (596 males; mean age
= 44 yr), Korea
Ambient Concentration
(ug/m3)*
26.8
10.9
16.4
•37.2
Outdoor: 19.4
Indoor: 18.3
Geometric mean: 46.8
Range of daily means: 7.4
to 68
Median PM25 outdoor:
28.3 pg/m3
Median PM25 indoor: 10.8
PM10
Summer: 46.4
Winter:73.0
Spring: 38.3
PM25
Summer: 33.9
Winter: 62.1
Spring: 30.8
PM0.25
Summer: 17.6
Winter: 30.5
Spring: 18.8
1-havg:33.2
Recording CRMM i c HF,
Length SDNN LF rMSSD
1 1 1
1 1 1
1 1 1
1 1
1 1
6-min
(Indoor PM25,
pre-supplement II 1
phase
presented)
5-min I I
24 h ->
15min I I
24 h |
5min III
LF/HF
->
1
r
r
r



i


Notes: Increases (|), decreases (J.) and no effects (-*) in HRV associated with PM concentration are indicated. Statistical significance was not necessary to categorize an effect as an increase or decrease.
For time domain measures moving average lags up to 24-h were explored. For frequency domain measures lags of 2-h, 4-h and 24-h were explored.
** All concentrations are means measured in u/m3, unless otherwise noted.


6.2.1.2.  Controlled Human Exposure Studies

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) cited one study in which HRV indicators of
parasympathetic activity increased relative to filtered  air control following a 2-h exposure with
intermittent exercise to PM2.5 CAPs (avg concentration 174 ug/m3) in both healthy and asthmatic
volunteers (Gong et al., 2003, 042106). This effect was observed immediately following exposure
and at 1 day post-exposure, but not at 4 h post-exposure. Although not statistically significant, HRV
(total power) increased following exposure to filtered air and decreased  following exposure to CAPs.
More recent controlled human exposure studies are described below.


      CAPs

      Two new studies have evaluated the effect of PM2 5 CAPs (2-h exposures to concentrations of
20-200 ug/m3) on HRV in elderly subjects (Devlin  et al., 2003, 087348: Gong  et al., 2004, 087964).
In both studies, subjects experienced significant decreases in HRV  following exposure to CAPs
relative to filtered air exposures. Interestingly, Gong et al. (2004, 087964) found that decreases in
HRV were more pronounced in healthy older adults than in those with COPD. In another study,
December 2009
6-8

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healthy and asthmatic adults were exposed to PM10_2.5 CAPs (avg concentration 157 ug/m3) for 2 h
with intermittent exercise (Gong et al., 2004, 055628). HRV was not affected immediately following
the exposure, but decreased in both groups at 4 and 22 h after the end of the exposure, with greater
responses observed in non-asthmatics. In a recent study among healthy adults exposed for 2 h with
intermittent exercise to PMi0_25 CAPs (avg concentration 89 ug/m3, MMAD 3.59 um, Chapel Hill,
NC), Graff et al. (2009, 191981) observed a significant decrease in overall HRV (SDNN) at 20 h
post-exposure, although no other measures of HRV were affected. Using a similar study design, the
same laboratory also evaluated the effect of ultrafme CAPs (avg concentration 49.8 ug/m3, <0.16 um
in diameter) on various HRV parameters (Samet et al., 2009, 191913) Relative to filtered air, both
HF and LF power increased 18 h following exposure to UF CAPs (36-42% increase per 105
particles/cm3). Exposure to UF CAPs, expressed as mass concentration, was not associated with
changes in HF power, and time domain parameters of HRV did not differ between CAPs and filtered
air in the 24 h following  exposure. Gong et al. (2008,  156483) also recently evaluated changes in
HRV following controlled human exposures to UF CAPs and reported a small and transient decrease
in LF power (p < 0.05) among healthy (n = 17) and asthmatic (n = 14) adults 4 h after the completion
of a 2-h exposure with intermittent exercise in Los Angeles (avg concentration 100 ug/m3, avg
PNC 145,000/cm3). No other measure of HRV was shown to be significantly affected by exposure to
UF CAPs. In one of the largest studies of controlled human exposures to CAPs conducted to date,
Fakhri et al. (2009, 191914) evaluated changes in HRV among 50 adult volunteers during 2-h
exposures to PM2.5 CAPs (127 ug/m3) and O3 (114 ppb), alone and in combination. Neither exposure
to CAPs nor O3 resulted in any significant changes in HRV relative to filtered air. However, trends
were observed suggesting a negative  concentration-response relationship between CAPs
concentration and SDNN, rMSSD, HF power and LF  power when subjects were concomitantly
exposed to O3.


     Diesel Exhaust

     In a double-blind, crossover, controlled-exposure study, Peretz et al. (2008, 156855) exposed
three healthy adult volunteers and 13 adults with metabolic syndrome while at rest to filtered air and
two levels of diluted DE (PM2.5 concentrations of 100 and 200  ug/m3) in 2-h sessions. HRV
parameters were assessed prior to exposure, as well as at 1, 3, 6 and 22 h following the start of
exposure, and included both time domain (SDNN and rMSSD) and frequency domain parameters
(HF  power, LF power, and the LF/HF ratio). In an analysis including all 16 subjects, the authors
observed an increase in HF power and a decrease in LF/HF 3 h after the start of exposure to
200 ug/m3 relative to filtered air. Although these changes were  statistically  significant (p < 0.05) the
effects were not consistent among the study subjects. No other significant effect of DE on HRV was
observed at either concentration  or time point. The authors attributed the lack of consistent effects to
the small and non-homogeneous population and the timing of measurement. There was no difference
in either baseline or diesel-induced changes in HRV parameters between normal individuals and
patients with  metabolic syndrome, although the number of normal individuals was quite small. It is
unclear if patients with metabolic syndrome were taking any medications.


     Model Particles

     Several additional  recent controlled human exposure studies have evaluated the effect of
laboratory generated particles on HRV in healthy and health-compromised individuals. In a random
order crossover controlled human exposure study, Routledge et al. (2006, 088674) examined the
effects of UF elemental carbon (EC) particles (50 ug/m3) alone and in combination with 200 ppb
SO2  on HRV  among 20 healthy older adults (age 56-75 yr), as well as 20 older adults with coronary
artery disease (age 52-74 yr). Five minute recordings of HRV data were obtained prior to and
immediately following the 1-h exposure, as well as 3 h post-exposure. In healthy subjects, exposure
to EC particles resulted in small  increases in RR-interval, SDNN, rMSSD, and LF power
immediately following exposure compared to filtered air control. At  3 h post-exposure, there were no
significant differences in HRV measures between EC particle and filtered air exposures. Conversely,
SO2-induced  decreases in HRV were  observed at 3 h, but not immediately following exposure.
Concomitant exposure to EC particles and  SO2 followed a pattern similar to that observed with SO2
December 2009                                 6-9

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alone, but did not reach statistical significance. Subjects with coronary artery disease did not
experience any significant changes in HRV following exposure to either pollutant. The authors
postulated that this lack of effect may be due to differences in medication between the two groups, as
70% of subjects with stable angina reported using (3 blockers, which are known to increase cardiac
vagal control. The lack of any significant effects on HRV following exposure to EC particles is an
important finding, as it provides evidence to suggest that the health effects observed following
exposure to PM may be due to particle constituents other than carbon, or to reactive species found on
the surface of the particle. These findings are in agreement with those of Zareba et al. (2009,
190101) who reported small and variable changes in HRV among a group of healthy adults
following exposure to UF EC. While exposure both at rest and during exercise to 10 ug/m3 UF EC
resulted in an increase in time domain parameters (rMSSD and SNDD), no such effect was observed
following exposure to a higher concentration of UF EC (25  ug/m3) in the same subjects. A recent
pilot study reported no effect of exposure to EC and ammonium nitrate particles (250-300 ug/m3)  on
HRV parameters in five adults with allergic asthma (Power  et al., 2008, 191982). However, when
the exposure occurred concomitantly with O3 (0.2 ppm), subjects were observed to experience
significant changes in both time and frequency HRV parameters. These observations should be
considered very preliminary as the study was limited by a small sample size (n = 5) and did not
evaluate the effect of exposure to O3 without particles. However, these findings are in agreement
with the previously described study of CAPs and O3 conducted by Fakhri et al. (2009, 191914). In
addition to the studies of laboratory generated carbon described above, Beckett et al. (2005, 156261)
used ZnO as a model particle and exposed twelve resting, healthy adults for 2 h to filtered air and
500 ug/m3 in the ultrafine (40.4 ± 2.7 nm) and fine (291.2 ± 20.2 nm) modes. Neither ultrafine nor
fine ZnO produced a significant change in any time or frequency domain parameter of HRV.


     Summary of Controlled Human Exposure Study Findings for Heart Rate Variability

     The results of several new controlled human exposure studies provide limited evidence to
suggest that acute exposure to near ambient levels of PM may be associated with small changes in
HRV. Changes in HRV parameters, however, are variable with some showing increased
parasympathetic activity relative to sympathetic activity and others showing the opposite. Although a
direct comparison between younger and older adults has not been made, PM exposure appears to
result in a decrease in HRV more consistently in healthy older adults (Devlin  et al., 2003, 087348;
Gong et al.. 2004. 087964).
6.2.1.3.   lexicological Studies

      Toxicological studies that examined HR and HRV are presented in the 2004 PM AQCD
(U.S. EPA, 2004, 056905) and overall demonstrated differing responses, which were collectively
characterized as providing limited evidence for PM-related cardiovascular effects. The studies
described that reported HR or HRV effects following PM exposure were conducted with a variety of
particle types (CAPs, diesel, ROFA, metals),  exposure methods (inhalation and IT instillation), and
doses (100-3,000 ug/m3 for inhalation; up to  8.3 mg/kg for IT instillation).


      CAPs

      Two groups of SH rats exposed to CAPs in Tuxedo, NY for 4 h (single-day mean PM2.5
concentrations 80 and 66 ug/m3; February 2001 and May 2001, respectively) demonstrated
decreased HR when exposure groups were combined that returned to baseline values when exposure
ceased (Nadziejko et al., 2002, 087460). Fine or UF H2SO4 exposure (mean concentration 225 and
468 ug/m3) did not induce any HR effects. Another study demonstrated a trend toward increased HR
in WKY rats following a 1- or 4-day PM2.5 CAPs exposure in Yokohama City, Japan (4.5 h/day; May
2004, November 2004, and September 2005), but the correlation between change in HR and
cumulative PM mass collected was not significant  (Ito  et al., 2008, 096823). Increased HR was
observed in SH rats exposed to PM2.5 CAPs for two 5-h periods during the spring (mean mass
concentration 202 ug/m3) in a suburb of Taipei, Taiwan (Chang et al., 2004, 055637). The response
December 2009                                  6-10

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was less prominent in the summer (mean mass concentration 141 ug/m3), despite the number
concentrations being similar for the two seasons (2.30><105 and 2.78x10 particles/cm3, respectively).
      For HRV, decreased SDNN was observed in SH rats exposed to PM2.5 CAPs (mean mass
concentration 202 ug/m3; mean number concentration 2.30><105 particles/cm3) for two 5-h periods
separated by 24 h (Chang et al., 2005, 088662).  Each of the four animals served as their own control
and the estimated mean PM effects for the SDNN decreases during exposure were 85-60% of
baseline. CAPs effects on rMSSD were less remarkable. In a study of Tuxedo, NY PM2.5 CAPs, no
acute changes in rMSSD or SDNN were observed in either ApoE~'~ or C57 mice when the 48-h time
period postexposure was evaluated (6 h/dayx5 day/wk; mean mass concentration over 5-mo period
110 ug/m3) (Chen and Hwang, 2005, 087218).


      Diesel Exhaust

      Anselme et al. (2007, 097084) used a MI model of congestive heart failure (CHF) where the
left anterior descending coronary artery of WKY rats was occluded to induce ischemia. After 3 mo of
recovery, rats were exposed to diesel emissions for 3 h (PM concentration 500 ug/m3; mass mobility
diameter 85 nm; NO2 1.1 ppm; CO 4.3 ppm) and decreases in rMSSD were observed during the first
2 h of the exposure, which returned to baseline values for the last hour of exposure. Healthy rats also
demonstrated decreased rMSSD when measured over the entire exposure period.


      Model Particles

      In WKY rats exposed to UF carbon particles (mass concentration 180 ug/m3; mean number
concentration 1.6x107 particles/cm3) for 24 h, HR increased and SDNN decreased during particle
inhalation (Harder  et al., 2005, 087371). These measures returned to baseline values during the
recovery period. This study provides evidence that ultrafine carbon exerts its effects through changes
in ANS mediation, as the HR and HRV responses occurred quickly after exposure started and
pulmonary inflammation was only  observed at the 24-h time point (and not at 4 h). SH rats exposed
to ultrafine carbon particles under the same conditions (mass concentration 172 ug/m3; mean number
concentration 9.0xl06 particles/cm3) demonstrated similar responses, albeit not until recovery days 2
and 3 (Upadhyay et al., 2008, 159345).
      A model of premature senescence has been developed by Tankersley  et al. (2003, 053919).
using aged AKR mice whose body weight abruptly declines ~5 wk prior to  death and is accompanied
by deficiencies in other vital physiological function including HR and temperature regulation. When
exposed to carbon black ([CB]; mean concentration 160 ug/m3; 3 h/dayx3 day), terminal senescent
mice responded with robust cardiovascular effects, including bradycardia and increased rMSSD and
SDNN (Tankersley et al., 2004, 094378). SDNN and LF/HF were also increased in healthy
senescent mice exposed to CB. These studies indicate that HR regulatory mechanisms are  altered in
susceptible mice exposed to PM (sympathetic and parasympathetic changes in healthy senescent
mice and increased parasympathetic influence in terminally senescent mice), which may translate
into lowered homeostatic competence in these animals. Results from the near-terminal group should
be interpreted with caution, as only three mice were in this group.
      Subsequent research with a similar exposure protocol (mean CB concentration 159 ug/m3)
used C57BL/6J and C3H/HeJ mice to determine whether an acute PM challenge can modify HR
regulation in two mice strains with differing baseline HR (Tankersley et al., 2007, 097910). There
were no CB-specific effects on HR or HRV in C3H/HeJ compared to C57BL/6J mice (average HR
-80 bpm lower than C3H/HeJ at baseline). Administration of a sympathetic antagonist (propanolol)
to C57BL/6J mice prior to CB exposure resulted in elevated HR and decreased rMSSD compared to
air during the last 2 h of exposure, indicating withdrawal of parasympathetic tone. There may be
differences in regional particle deposition based on strain-specific breathing patterns that may affect
HR and HRV responses. However, this study revealed that inherent autonomic tone, which is
genetically varied between these mouse strains, may affect cardiovascular responses  following PM
exposure. In extrapolating these results to humans, individual variation in genetic factors likely plays
some role in PM-induced adjustments in HR control via the ANS.
      A recent study in mice  (C3H/HeJ, C57BL/6J, and C3H/HeOuJ) examined the effects of a 2-h
O3 (mean concentration 0.584 ppm) pretreatment followed by a 3-h exposure to CB (mean
December 2009                                  6-11

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concentration 536 ug/m3) on HR and HRV measures (Hamade  et al., 2008, 156515) HR decreased
to the greatest extent during O3 pre-exposure for all strains that were then exposed to CB. The
percent change in SDNN and rMSSD were increased in C3H mice during O3 pre-exposure and CB
exposure compared to the filtered air group; however, these HRV parameters gradually decreased
over the duration of the experiment and appeared to be O3 dependent. Together, these findings
indicate that increases in parasympathetic tone and/or decreases in sympathetic input may explain
the observed bradycardia. In a subset of all mice pre-exposed to O3, rMSSD remained significantly
elevated during the CB  exposure compared to filtered air. The results from this study confirm what
was observed in Tankersley et al. (2007, 097910) in that genetic determinants affect HR regulation in
mice with exposure to air pollutants.


      Summary of lexicological  Study Findings for Heart Rate and Heart Rate Variability

      Both increases and decreases in HR have been observed in rats or mice following PM
exposure. Fine or UF  H2SO4 did not result in HR changes in SH rats. Similarly, decreased SDNN
was reported for UF CAPs exposure and lowered rMSSD was observed with diesel exposure. In
near-terminal senescent mice, HRV responses were robust following CB exposure and represented
increased parasympathetic influence. Strain differences in baseline HR and HRV likely contribute to
PM responses. HRV changes with preexposure to O3 and CB appeared to be O3 dependent, although
rMSSD remained elevated during PM exposure.


      Source Apportionment and PM Components

      An additional analysis of CAPs data (Chen and Hwang, 2005, 087218; Hwang et al., 2005,
087957) was conducted to link short-term HR and HRV effects to major PM  source categories using
source apportionment methodology (Lippmann et al., 2005, 087453).
      The source categories were: (1) regional secondary SO4Z~ comprised of high S, Si, and OC
(mean 63.41 ug/m3); (2) resuspended soil  characterized by high concentrations of Ca, Fe, Al, and Si
(mean concentration 5.88 ug/m3); (3) fly ash emissions from power plants burning residual oil in the
eastern U.S. and containing high levels  of V,  Ni, and Se (mean concentration 1.53 ug/m3); and (4)
motor vehicle traffic and other unknown sources (34.92 ug/m3) (Lippmann et al., 2005, 087453).
Exposures occurred from 9:00 a.m. to 3:00 p.m., 5 days/wk for 5 mo. PM2.5 mass was associated
with a daily interquartile change of -4.1 beat/min HR during exposure in ApoE"7" mice1 and a similar
magnitude of effect was observed with resuspended soil (-4.5 beat/min).  Resuspended soil was also
associated with a HR increase in the afternoon post-exposure (2.6 beat/min);  the secondary SO42~
factor was linked to lowered HR in the same period (-2.5 beat/min). A 6.2% increase in rMSSD
collected in the afternoon post-exposure was associated with the residual oil factor, compared to a
5.6% and 2.4% decrease in rMSSD at night for secondary SO42~ and PM2 5 mass,  respectively.
Resuspended soil was associated with a 4.3% increase in rMSSD the night following CAPs
exposure. The residual oil and secondary SO42~ categories showed similar statistically significant
parameter estimates for SDNN as rMSSD.
      Recent studies of ECG alterations in mice have indicated  a role for PM-associated Ni in
driving the cardiovascular effects. Lippman et al.  (2006, 091165) presented a posthoc analysis of
daily variations in PM2.5 CAPs (mean concentration: 85.6 ug/m3; 7/21/ 2004-1/12/2005; Tuxedo,
NY) and changes in cardiac dynamics in ApoE"7" mice. On the 14 days that the exposed mice had
unusually elevated HR, Ni, Cr, and Fe comprised 12.4% of the PM mass, compared to only 1.5% on
 Atherosclerosis and related pathways have been studied primarily in the Apolipoprotein E (ApoE) knockout mouse. Developed by
Nobuyo Maeda's group in 1992 (Piedrahita et al., 1992, 156868; Zhang et al., 1992, 157180). the ApoE-/- mouse and related models have
become the workhorse of atherosclerosis research over the past 15 years. The ApoE molecule is involved in the clearance of fats and
cholesterol. When ApoE (or the LDL receptor) is deleted from the genome, mice develop severely elevated lipid and cholesterol profiles;
ApoE"'" mice on a high-fat ("Western") diet exhibit cholesterol levels exceeding 1000 mgdL (normal is —150 mgdL) (Huber et al., 1999,
156575; Moore et al., 2005, 156780). As a result, the lipid uptake into the vasculature is increased and the atherosclerotic process is
dramatically hastened. Furthermore, the LDLs in ApoE" mice are highly susceptible to oxidation (Hayek et al., 1994, 156527). which may
be a crucial event in the air pollution-mediated vascular changes. However it should be noted that this model is primarily one of peripheral
vascular disease rather than coronary artery disease.
December 2009                                   6-12

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the other 89 days. Back trajectory analyses indicated high-altitude winds from the northwest that did
not traverse population centers and industrial areas except the Sudbury Ni smelter in Ontario,
Canada. On the 14 days that high HR was observed, the HR elevation lasted for two days, but only
the current day CAPs concentration was statistically significant. SDNN decreases were statistically
significant for all three lags (0, 1,2 days). The GAM regression analysis showed that only Ni
produced a statistically significant effect for HR and  SDNN.


6.2.2.   Arrhythmia

      Epidemiologic and toxicological studies presented in the 2004 PM AQCD (U.S. EPA, 2004,
056905) provided some evidence of arrhythmia following exposure to PM. However, a positive
association between PM and ventricular arrhythmias  among patients with implantable cardioverter
defibrillators was only observed in  one study conducted in Boston, MA, while toxicological studies
reported arrhythmogenesis in rodents following exposure to ROFA, DE, or metals. Recent
epidemiologic studies have confirmed the findings of PM-induced ventricular arrhythmias in Boston,
MA, and have also reported increases in ectopic beats in studies conducted in the Midwest and
Pacific Northwest regions of the U.S. In addition, two studies from Germany have demonstrated
positive associations between traffic and combustion particles and changes in repolarization
parameters among patients with IHD. Findings of recent toxicological studies are mixed, with both
demonstrated decreases and increases in frequency of arrhythmia following exposure to CAPs.


6.2.2.1.   Epidemiologic Studies


      Studies of Arrhythmias Using Implantable Cardioverter Defibrillators

      One study reviewed in the 2004 PM AQCD assessed  the effect of short-term fluctuations in
PM2.5 on ventricular arrhythmias  and several recent studies  examining this relationship have been
conducted. Ventricular ectopy and arrhythmia include ventricular premature beats (VPBs),
ventricular tachycardia (VT), and ventricular fibrillation (VF). VPBs are spontaneous beats
originating from either the right or left ventricles. VT refers to three or more VPBs in succession at a
rate of 100 beats per minute or greater, while VF is characterized by rapid and disorganized
ventricular electrical activation incapable  of generating an organized mechanical contraction or
cardiac output. AF is the most common  type of arrhythmia.  In this condition, ectopic electrical
impulses arising in the atria or pulmonary veins, i.e.,  outside their normal anatomic origin (the
sinoatrial node), can result in atrioventricular dilatation, dysfunction, and/or thromboembolism.
Despite being  common, clinical and subclinical forms of AF are associated with reduced functional
status and quality of life. Moreover, the  arrhythmia accounts for a large proportion of ischemic
stroke (Laupacis et al., 1994, 190901; Prystowsky et al., 1996, 156031) and is a strong risk factor
for CHF (Roy  et al., 2009,  190902). contributing to both cardiovascular disease (CVD) and all-
cause mortality (Kannel  et al., 1983,  156623).
      Ventricular arrhythmia is commonly associated with myocardial infarction, heart failure,
cardiomyopathy, and other forms of structural (e.g., valvular) heart disease. Pathophysiologic
mechanisms underlying this established cause of sudden cardiac death include activators and
facilitators of arrhythmia, such as electrolyte abnormalities, modulation of the ANS, membrane
channels, gap junctions, oxidant stress, myocardial stretch and ischemia.
      Previously, Peters et al. (2000, 011347) conducted a pilot study in Boston, MA to examine the
association between short-term changes in ambient air pollutant concentrations and increased risk of
ventricular arrhythmias, among a cohort of patients with implantable cardioverter defibrillators
(ICD). ICDs continuously monitor cardiac rhythm and upon detection of an abnormal rhythm (i.e.,
rapid HR), they can be programmed to deliver pacing and/or shock therapy to restore normal sinus
rhythm. Those abnormal rhythms that are most severe or rapid are assumed to be due to VT or VF
(i.e., life-threatening arrhythmias), and are thus treated with electric shock. These ICD devices also
store information on each abnormal rhythm detected, including the date, time, and therapy given.
Thus, using the date and time of those arrhythmias resulting in electric shock, Peters et al. (2000,
011347) reported an increased risk of ICD shock associated with mean NO2 concentration in the
December 2009                                  6-13

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previous two days. Among subjects with frequent events (10 or more during 3 yr of follow-up) an
increased risk of ICD shock was also associated with interquartile range increases in CO, NO2,
PM2.5, and BC in the previous 2 days. Several studies were conducted to confirm these findings. The
study characteristics, as well as the reported effect estimates and 95% CI associated with each PM
metric, are shown in Table 6-2.
      Dockery et al. (2005, 078995: 2005, 090743) conducted a follow-up study of ICD patients
living in eastern Massachusetts and followed subjects for a longer period of time (up to 7 yr). They
were the first to review the ECG, classify each ICD-detected arrhythmia (e.g., ventricular
arrhythmia, VF, atrial tachycardia, sinus tachycardia, etc.), and include only ventricular arrhythmias
(VF or VT; excluding supraventricular arrhythmias). In single-pollutant models using generalized
estimating equations, increased risks of confirmed ventricular arrhythmias were associated with IQR
increases in every pollutant (PM2.5, BC, SO42~, NO2, SO2,  O3, and PNC). Among those with a prior
ventricular arrhythmia in the past three days, interquartile  range increases in 2-calendar-day mean
PM2 5, NO2, SO2, CO, O3,  SO42~, and BC concentrations were all associated with significant and
markedly higher risks of ventricular arrhythmia than among those without a prior arrhythmia. The
pollutants associated with  increased risk of ventricular  arrhythmia implicate traffic pollution.
      Rich et al. (2005, 079620) conducted a case-crossover analysis of these same data to
investigate moving average pollutant concentrations lagged <48 h. They reported an increased risk
of ventricular arrhythmia associated with mean PM25 and  O3 concentrations in the 24 h before the
arrhythmia. Each pollutant effect appeared independent in two pollutant models. In single-pollutant
models, NO2 and SO2 were associated with increased risk, but when included in two pollutant
models with PM2 5, only PM2 5 remained associated with increased risk. They did not, however, find
evidence of a more acute arrhythmic response to pollution (i.e., larger risk estimates associated with
moving averages <24 h before arrhythmia detection). In an ancillary case-crossover analysis of data
from the Boston ICD study, Rich et al. (2006, 088427)  identified 91 confirmed episodes of
paroxysmal AF among 29  subjects. In single pollutant models, they reported a significantly increased
risk of AF associated with mean O3 and PM25 concentrations in the hour before the arrhythmia and
BC concentration in the 24 h before the arrhythmia.
      Rich et al. (2006, 089814) conducted another case-crossover study in the St. Louis, MO
metropolitan  area.  Using the same methods as in Boston, they reported increased risk of ventricular
arrhythmia associated with mean SO2 concentration in  the 24 h before the arrhythmia, but not PM2 5
(in  single-pollutant models). Again, they found no evidence of an arrhythmic response with moving
average pollutant concentrations <24 h before the arrhythmia.
      In Vancouver, Canada, Vedal et al. (2004, 055630) did not find increased risk of ICD shocks
associated with increases in any pollutant concentration (PMi0, O3, SO2, NO2, and CO). Secondary
analyses among those subjects with two or more discharges per year, and analyses stratified by
season were also null for PMi0, although an association with SO2 (lag 2 days) was observed. A case
crossover analysis  of these same data examining additional particle pollutant concentrations
available for a shorter time frame (e.g., PM2 5, SO42~, EC, and OC) also found no increased risk of
ICD shock associated with any pollutant (Rich et al., 2004, 055631).
      The largest ICD study to date examined the risk of ventricular arrhythmias associated with
increases in the daily concentration of numerous PM and gaseous pollutants in Atlanta,  GA (Metzger
et al., 2007, 092856) (see Table 6-2 for specific pollutants  evaluated). Similar to Vedal et al. (2004,
055630). they did not find significant or consistently increased risk of a ventricular arrhythmia
associated with any IQR increase in mean daily PM or  gaseous pollutant concentration at any lag
examined.
      Ljungman et al. (2008, 180266) conducted a similar study, using case-crossover methods, on
ICD patients in Gothenburg and Stockholm, Sweden. They investigated the triggering of confirmed
ventricular arrhythmias by ambient PMi0 and NO2 concentrations, and reported increased relative
odds of ventricular arrhythmia associated with each 10 (ig/m3 increase in the 2-h ma PMi0
concentration (OR = 1.22  [95% CI: 1.00-1.51]), with a smaller non-significant risk associated with
each 10.3 ug/m3 increase in the 24-h ma PMi0 concentration (OR = 1.23 [95%  CI: 0.87-1.73]). The
NO2 and PM2 5 effect estimates were much smaller and not statistically significant. Effect estimates
were larger for events occurring near the air pollution monitors in Gothenburg (compared to
Stockholm).
      Albert et al.  (2007, 156201). although not investigating associations with ambient pollution,
conducted a case-crossover study of the association between ventricular arrhythmia and traffic
exposure in the hours before the arrhythmia. They reported an increased risk of ventricular
December 2009                                  6-14

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arrhythmia associated with traffic exposure or driving in the previous hour. They hypothesized that
this increased risk was due to either a stress response from being in a car in heavy traffic, or from
traffic-generated air pollution, or a combination of both.
Table 6-2.
Reference
Dockery et al.
(2005, 078995;
2005, 0907431
Eastern MA
Rich et al. (2005,
0796201
Eastern MA
Rich et al. (2006,
0898141
St. Louis metro
area
Vedal et al.
(2004, 0556301
Vancouver, BC,
Canada
Ljungman et al.
(2008, 1802661
Gothenburg and
Stockholm,
Sweden
Rich et al. (2004,
0556311
Vancouver, BC,
Canada
Epidemiologic studies of ventricular arrhythmia and ambient PM concentration, in
patients with implantable cardioverterdefibrillators.
Outcome and
Sample Size
N=670 days with >1
confirmed ventricular
arrhythmias among
n=84 subjects
N=798 confirmed
ventricular
arrhythmias among
n=84 subjects
N=139 confirmed
ventricular
arrhythmias among
n=56 subjects
N=257 days with >1
ICD shock among
n=50 subjects
N=114 ventricular
arrhythmias among
73 subjects. 211 total
subjects were
followed.
N=77 to 98 days with
> 1 ICD shock
among n=34
subjects
Study Design and r*nnnii,,tnnt* PM
Analytic Method c°P°llutants Metric
Generalized estimating
equations Ng2] cc, Sg2]
Lags Evaluated: 2 calendar ^3
day means
Time-stratified case--
crossover study. NQ CQ SQ
Conditional logistic regres- 0 ' ' '
sion. Lags evaluated: 3, 6, 3
24, 48-h ma
Time-stratified
case-crossover study.
Conditional logistic N°2> co> s°2>
regression. Lags 3
Evaluated: 6, 12, 24, 48-h
ma
Generalized estimating
equations NC,2] co, S02,
Lags Evaluated: 0, 1,2, 3 °3
daily ma
Conditional logistic
regression NC,2
Lags evaluated: 2 h, 24 h
Am bi-directional
case-crossover study.
Conditional logistic
regression N02, CO, S02,
03
Lags Evaluated: 0, 1, 2,
and 3 day ma
PM25
BC
Sulfate
PNC
PM25
BC
PM25
EC
Organic
Carbon
PM10
PM,0,
PM25
PM25
PM10
EC
Organic
Carbon
Sulfate
Ambient
Concentration
Daily Median:
10.3|jg/m3
Daily Median:
0.98 pg/m3
Daily Median:
2.55 pg/m3
Daily Median:
29,300 particles/cm3
Daily Median:
9.8 pg/m
Daily Median:
0.94 pg/m3
Daily Median:
16.2|jg/m3
Daily Median:
0.6 pg/m3
Daily Median:
4.0 pg/m
Daily Median:
11.6|jg/m3
Median Gothenburg
2h:18.95|jg/m3
24 h: 19.92 pg/m3
Stockholm
2 h: 14.62 pg/m3
24 h: 15.23 pg/m3
Median
Stockholm pg/m3
2 h: 9.17
24 h: 9.49 pg/m3
Daily Mean:
8.2 pg/m3
Daily Mean:
13. 3 pg/m3
Daily Mean:
0.8 pg/m3
Daily Mean:
4.5 pg/m3
Daily Mean:
1.3 pg/m3
Lag and its
Increment
Units
2 day
6.9 pg/m3
2 day
0.74 pg/m
2 day
2.04 pg/m3
2 day
19,120
particles/cm3
24-h ma
7.8 pg/m3
24-h ma
0.83 pg/m3
24-h ma
9.7 pg/m3
24-h ma
0.5 pg/m3
24-h ma
2.3 pg/m3
Lag Day 0
5.6 pg/m3
2-hma:14.16
pg/m3
24-h ma: 11:49
pg/m3
2-h ma: 6.69
pg/m3
24-h ma: 5.27
pg/m3
Lag Day 0
5.2 pg/m3
Lag Day 0
7.4 pg/m3
Lag Day 0
0.4 pg/m3
Lag Day 0
2.2 pg/m3
Lag Day 0
0.9 pg/m
OR
1.08
1.11
1.05
1.14
1.19
0.93
0.95
1.18
1.08
1.00*
2h:
1.31
24 h:
1.24
2h:
1.23
24 h:
1.28
LOT
0.9t
1.1T
1.1T
0.9t
95%
Confidence
Interval
0.96,
0.95,
0.92,
0.87,
1.02,
0.74,
0.72,
0.93,
0.81,
0.82,
1.00,
0.87,
0.84,
0.90,
0.9,1
0.5,1
0.9,1
0.9, 1
0.7, 1
1.22
1.28
1.20
1.50
1.38
1.18
1.27
1.50
1.43
1.19*
1.72
1.76
1.80
1.84
•1T
•5T
•3T
•3T
•2T
December 2009
6-15

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"-— r?Ł TagES
Generalized estimating
Metzgeretal. N=6287 confirmed equations
(2007, 092856) ventricular
arrhythmias among Lags Evaluated:
Atlanta, GA n=51 8 subjects
0, 1, and 2 day ma
<*— • A
PM25
PM10
PM,0-2.5
NO* «>. SO* PM25EC
PM25 OC
PM25
S042"
PM25 water
soluble
elements
Ambient
Concentration
Daily Median:
16.2|jg/m3
Daily Median:
26.4 pg/m3
Daily Median:
8.7 pg/m
Daily Median:
1.4|jg/m3
Daily Median:
3.9 pg/m3
Daily Median:
4.1 pg/m3
Daily Median:
0.022 pg/m3
Units
24-h ma
10|jg/m3
24-h ma
10|jg/m3
24-h ma
5 pg/m3
24-h ma
1 pg/m3
24-h ma
2 pg/m3
24-h ma
5 pg/m3
24-h ma
0.03 pg/m3
OR
1.00
1.00
1.03
1.01
1.01
0.99
0.95
95%
Confidence
Interval
0.95, 1.0
0.97, 1.03
1.00, 1.07
0.98, 105
0.98, 1.03
0.93, 1.06
0.90, 1.00
Estimated from Figure 3 Vedal et al. (2004, O556301.t Estimated from Figure 3 Rich et al. (2004, 05563H
      Summary of Epidemiologic Studies of Arrhythmias using ICDs

      Since 2004, only two studies (in Boston and Sweden), reported adverse associations of PM2.s,
other size fractions and components with ICD-detected ventricular arrhythmias (Dockery et al.,
2005, 078995: Dockery  et al., 2005, 090743; Ljungman  et al., 2008, 180266; Rich et al., 2005,
079620). Studies of ICD-detected ventricular arrhythmias conducted elsewhere did not report
associations (Dusek et al., 2006, 155756; Metzger et al., 2007, 092856; Rich et al., 2004, 055631;
Vedal et al., 2004, 055630) nor was an association observed in a study of PMi0 and ICD shock in
Vancouver, Canada (Vedal et al., 2004, 055630). A range in exposure lags was evaluated in the
Boston study  (3 h-3 days) (Dockery et al., 2005, 078995; Dockery et al., 2005, 090743; Rich et al.,
2005, 079620) and Sweden study (2 h and 24 h) (Ljungman  et al., 2008, 180266). Reasons for the
inconsistent findings may include differing degrees of exposure misclassification within each study
or city due to differences in PM composition and pollutant mixes (e.g., less transition metals and
sulfates in the Pacific Northwest than the Northeast U.S.), and differences in the size of study areas
(Boston: within 40 km of PM2.5 monitoring site; Vancouver: Lower Mainland of British Columbia 90
km east of Vancouver). In addition, Rich et al. (2005, 079620) reported that use of the mean
pollutant concentration from the specific 24 h before the arrhythmia rather than just the day of the
arrhythmia, resulted in less exposure misclassification and less bias towards the null, possibly
explaining the lack of association when using just the  day of ICD discharge and daily PM
concentrations.


      Ectopy Studies Using ECG Measurements

      A few panel studies have used ECG recordings to evaluate associations between ectopic beats
(ventricular or supraventricular) and mean PM concentrations in the previous hours and/or days
(Berger et al., 2006, 098702;  Ebelt  et al., 2005, 056907; Liao  et al., 2009,  199519; Sarnat et al.,
2006, 090489).
      Ectopic beats are defined as heart beats that originate at a location in the heart outside of the
sinus node. They are the most common disturbance in heart rhythm. Ectopic beats  are usually
benign, and may present with or without symptoms, such as palpitations or dizziness. Such beats can
arise in the atria, AV node, conduction system or ventricles. When the  origin is in the atria the beat  is
called an atrial or supraventricular ectopic beat. When such a beat occurs earlier than expected it is
referred to as a premature supraventricular or atrial premature beat. Likewise, when the origin is in
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the ventricle the beat is defined as a ventricular ectopic beat, or when early a premature ventricular
beat. When three or more occur ectopic beats occur in succession, this is called a non-sustained run
of either supraventricular (atrial) or ventricular origin. When the rate of the run is greater than 100
beats per minute it is defined as a tachycardia. Sustained VT are the arrhythmias investigated in the
ICD studies described above.
      Using data from the WHI done in 59 U.S. exam sites in 24 cities,  Liao et al. (2009, 199519)
estimated mean PM2.5 and PM^ concentrations at the addresses of 57,422 study subjects undergoing
ECG monitoring. They then estimated the risks of ventricular and supraventricular ectopy during that
10-s ECG recording associated with increases in mean PMi0 and PM2.5 concentrations on the same
day and previous 2 days, as well as over the previous 30 days. Mean PM2.5 and PMi0 concentrations
during the study period were 13.8  and 27.5 (ig/m3, respectively. Using a 2-stage random effects
model, they reported that among smoking subjects, each 10 (ig/m3 increase in PM2.5 concentration on
lag day  1 was associated with a significantly increased risk of ventricular ectopy (OR = 2.0 [95% CI:
1.32-3.3]). Similarly, each 10  (ig/m3  increase in lag 1 PMi0 concentration was associated with an
increased risk of ventricular ectopy (OR = 1.32 [95% CI: 1.07-1.65]). The lag day 2 PM2.5 risk
estimate was similar in size, but not statistically significant. There were no associations between
PMio, PM2 5 and supraventricular ectopy among smokers or non-smokers, and no association with
any PM metric and ventricular ectopy among non-smokers.
      Sarnat et al. (2006, 090489) conducted a panel study among 32 nonsmoking older adults
residing in Steubenville, OH. In this  study, the median daily PM2 5, SO42~, and EC concentrations
were 17.7, 5.7, and 1.0 (ig/m3, respectively They used logistic regression models to examine lagged
effects of 1- to 10-day ma concentrations of PM25, SO42~, EC, O3, NO2,  and SO2. Supraventricular
ectopy and ventricular ectopy were measured using Holter monitors during a 30-minute protocol  of
alternating rest in the supine position, standing, walking and paced breathing. In single-pollutant
models, each 10.0 (ig/m increase in  5-day mean PM25 concentration was associated with increased
risk of supraventricular ectopy (OR = 1.42 [95% CI: 0.99-2.04]), but not ventricular ectopy
(OR = 1.02 [95% CI: 0.63-1.65]).  Similarly, increased risk of supraventricular ectopy, but not
ventricular ectopy, was associated with each interquartile range increase in 5-day mean SO42~ and O3
concentration.
      Ebelt et al. (2005, 056907) conducted a repeated measures panel study of 16 patients with
COPD in Vancouver, British Columbia. Their goal was to evaluate the relative impact of ambient
and non-ambient exposures to PM25, PMi0, and PMi0_2.5 on several health measures. Subjects wore
an ambulatory ECG monitor for 24 h to record heart rhythm data and ascertain supraventricular
ectopic beats. The mean PM25 concentration during this study was 11.4  ug/m3. Using mixed models
with random subjects effects to investigate only same-day PM concentrations,  an increase in
supraventricular ectopic beats was associated with same day ambient exposures to each PM size
fraction.
      Berger and colleagues (2006, 098702) conducted a panel study of 57 men with coronary heart
disease living in Erfurt, Germany.  Using 24-h ECG measurements made once every 4 wk, they
studied associations between runs  of supraventricular and ventricular tachycardia and lagged
concentrations of PM2.5, UFP (0.01-0.1 (im), ACP (0.1-1.0 (im), SO2, NO2, CO, and NO. Using
GAMs,  as well as Poisson and linear regression models, they reported increases in supraventricular
tachycardia and the number of runs of ventricular tachycardia associated with 5-day mean PM25,
UFP counts, and ACP counts.  They found these associations at all lags evaluated (during ECG
recording, 0-23  h before, 24-47 h before, 48-71 h before, 72-95 h before, and 5-day mean), but the
largest effect estimates were generally associated with the 24- to 47-h mean and the 5-day mean.
      Summary of Ectopy Studies Using ECG Measurements

      Four studies of ectopic beats and runs of supraventricular and ventricular tachycardia, captured
using ECG measurements, all report at least one positive association. Further, they report findings in
regions other than Boston and Sweden (i.e., Midwest U.S., Pacific Northwest, 24 U.S. cities, and
Erfurt, Germany). A range of lags and/or moving averages were investigated (0-30 days) with the
strongest effects observed for either the 5-day mean, same day, or 1-day lagged PM concentrations.
Taken together, these ICD studies and ectopy studies provide evidence of an arrhythmic response to
PM, although further study is needed to understand the variable ICD study findings.
December 2009                                  6-17

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      ECG Abnormalities Associated with the Modulation of Repolarization

      No reported investigations of the relationship of PM concentration and ECG abnormalities
indicating arrhythmia were conducted prior to 2002 and thus were not included in the 2004 PM
AQCD (U.S. EPA, 2004, 056905). Abnormalities in the myocardial substrate, myocardial
vulnerability, and resulting repolarization abnormalities are believed to be key factors contributing to
the development of arrhythmogenic conditions such as those discussed above. These abnormalities
include ECG measures of repolarization such as QT duration (time for depolarization and
repolarization of the ventricles), T-wave complexity (a measure of repolarization morphology), and
T-wave amplitude (height of the T-wave). Abnormalities in repolarization may also identify subjects
potentially at risk of more serious events such as sudden cardiac death (Atiga et al., 1998, 156231;
Berger et al., 1997, 155688; Chevalier et al., 2003, 156338; Okin  et al., 2000, 156002; Zabel et al.,
1998, 156176). Recent studies of changes in these measures following acute increases in air
pollution are described below.
      Two studies conducted in Erfurt, Germany, (Henneberger  et al., 2005,  087960; Yue  et al.,
2007, 097968) examined the association between measures of repolarization  (QT duration, T-wave
complexity, T-wave amplitude, T-wave amplitude variability) and particulate  air pollution.
Henneberger et al. (2005, 087960) conducted a panel study of 56 males with  IHD. Each subject was
measured every 2 wk for 6 mo. During the study, the median daily PM2.5, EC, and OC concentrations
were 14.9, 1.8, and 1.4 ug/m3,respectively. The median count of UFP was 11,444 particles/cm3,
while the median count of ACP (0.1-1.0 (im) was 1,238 particles/cm3. They examined the change in
these ECG parameters associated with the mean pollutant (UFP, ACP, PM2.5,  OC, and EC)
concentrations 0-5, 6-11, 12-17, 18-23, and 0-23 h before, and 2-5 days before the ECG
measurement. Significant decreases in T-wave  amplitude were associated with PM2.5 mass, UFP, and
ACP. Each 16.4 (ig/m3 increase in the mean PM2.5  concentration in the previous 5 h was associated
with a 6.46 (iV decrease in T-wave amplitude (95% CI: -10.88 to -2.04). Each 0.7 (ig/m3 increase in
the mean OC concentration in the previous 5 h was associated with a 4.15 ms increase in QT interval
(95%  CI: 0.22-8.09). There was a similar sized effect for 24-h mean OC concentration. Significant
increases in the variability of T-wave complexity were also associated with acute increases in EC and
OC concentration.

      Yue et al. (2007, 097968) then used positive matrix factorization to identify 5 sources of
ambient PM (airborne soil, local traffic-related UFP, combustion-generated aerosols, diesel traffic-
related particles, and secondary aerosols). Using similar statistical models, they examined the
association between these same repolarization changes and incremental increases in the mean
concentration of each particle source in the 24 h before the ECG measurement. They also examined
associations with CRP and vWF concentrations in the blood. Both UFP from local traffic and diesel
particles from traffic had the strongest associations with repolarization parameters.
      Summary of Epidemiologic Studies of ECG Abnormalities Associated with the
      Modulation of Repolarization

      These two analyses demonstrate associations between PM pollution and repolarization
changes, at lags of 5 h to 2 days. Moreover, the findings from the Yue et al. (2007, 097968) study
demonstrate a potential role of traffic particles/pollution.


6.2.2.2.   lexicological Studies
      The ECG of animal research models frequently exhibit different characteristics than that of
humans. Mice and rats are notable in this regard, as they do not have an isoelectric ST-segment
typical of larger species, likely owing  to their rapid heart rates (-600 and -350 bpm, respectively)
and repolarizing currents. However, the ultimate function of the pumping heart is conserved and
reflected by the ECG in a remarkably  consistent manner across  species. Thus, atrial depolarization
causes an electrical inflection represented by the P-wave, ventricular depolarization elicits the QRS
complex, and the T-wave represents repolarization of the ventricles.
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      The earliest indication that there may be cardiovascular system effects of PM came from ECG
studies in susceptible animal models (rats with pulmonary hypertension and dogs with coronary
occlusion), which were summarized in the 2004 PM AQCD (U.S. EPA, 2004, 056905). However, a
study of dogs exposed to ROFA did not demonstrate ECG changes, perhaps due to differences in
disease state, as these were the oldest dogs in the colony with signs of preexisting, naturally
occurring heart disease (Muggenburg et al., 2000, 189163). Much of the research conducted since
the release of the last PM AQCD has been focused on exploring susceptibility or varying exposure
methodologies, with little new evidence into the mechanisms for ECG changes of inhaled PM.


      CAPS

      Wellenius et al. (2004, 087874) used a susceptible model that was previously shown to
produce significant results with exposures to ROFA (Wellenius  et al., 2002, 025405) to examine
ECG-related PM2.5 effects.  Using an anesthetized model of post-infarction myocardium sensitivity,
Wellenius and colleagues tested the effects of Boston, MA CAPs on the induction of spontaneous
arrhythmias in SD rats (1 h; mean mass concentration 523.11  ug/m3; range of mass concentration
60.3-2202 ug/m3). Decreased (67.1%) VPB frequency was observed during the post-exposure period
in rats with a high number of pre-exposure VPB. No interaction was observed with coexposure to
CO (35 ppm). CAPs number concentration or the mass concentration of any single element did not
predict VPB frequency. In a follow-up publication, a decreased number of supraventricular ectopic
beats (SVEB) was reported with CAPs (mean mass concentration 645.7 ug/m3) (Wellenius et al.,
2006, 156152). Furthermore, an increase in CAPs number concentration of 1,000 particles/cm3 was
associated with a 3.3% decrease in SVEB frequency. The findings of decreased ventricular
arrhythmia differ from those observed following ROFA exposure in the same animal model in that
an increased frequency of premature ventricular complexes was observed with ROFA, albeit the
ROFA exposure concentration was >3,000 ug/m3 (Wellenius et al., 2002, 025405). It is difficult to
directly compare the results of these studies due to differences in exposure  concentrations and
particle type, but collectively they may  suggest an important role for the soluble components of PM,
including transition metals, as only ROFA induced increases in ventricular  arrhythmia occurrence.
      In older rats (Fisher 344;  -18 months) exposed to PM2.5 CAPs in Tuxedo, NY (4 h; mean
concentration 180 ug/m3; August 2000), the frequency of delayed beats was greater than in rats
exposed to air (Nadziejko et al., 2004, 055632). The majority of these beats were characterized as
pauses (a delay of 2.5 times the adjacent interbeat intervals) rather than premature beats. When the
same animals were exposed to generated UF carbon particles (single-day concentrations 500 and
1280 ug/m3) or SO2 (1.2 ppm), no significant differences were observed in arrhythmia frequency
between air controls and  exposed animals. The authors also report using the same protocol for young
WKY rats (concentration 215 ug/m3) and very few arrhythmias were  observed, thus precluding
statistical analysis. The results of this study indicate (1) involvement of the sino-atrial node, as the
observed arrhythmias were mostly of a delayed nature; and (2) particle size and PM25 constituents
may play a role in these effects.


      Diesel and Gasoline Exhaust

      Anselme and colleagues (2007, 097084) exposed rats with and without induced CHF to DE for
3 h (PM concentration 500 ug/m3; mass mobility diameter 85  nm; NO2 1.1  ppm; CO 4.3 ppm).
While no dramatic change was noted in HR, prominent increases in the incidence of VPB were
observed in CHF rats, which lasted at least 4-5 h after exposure ceased. The duration  of VPB
attributable to diesel exposure in CHF rats lasted much longer than the rMSSD change (>5 h
post-exposure), indicating that the HRV response was not driving the increased arrhythmia
incidence. It is interesting to contrast the work of Anselme with the studies by Wellenius et al. (2002,
025405; 2004, 087874; 2006, 156152). as the  arrhythmia incidence in the acute infarction model was
greatest with ROFA, while the CHF model demonstrated sensitivity to DE  exposure. However,
several differences in the research designs preclude strong comparisons.
      Using ApoE"7" mice on a high-fat diet as a model of pre-existing coronary insufficiency
(Caligiuri  et al., 1999, 156318). Campen and  colleagues studied the impact of inhaled diesel and
gasoline exhaust and road dust (6 h/day><3 day) on ECG morphology  (Campen et al., 2005, 083977;
December 2009                                 6-19

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2006, 096879). Moreover, a high efficiency particle filter was used to compare the whole exhaust
with an atmosphere containing only the gaseous components. For gasoline exhaust, the
PM-containing atmosphere (PM mean concentration 61 ug/m3; PNMD 15 nm; NOX mean
concentration 18.8 ppm; CO mean concentration 80 ppm) induced T-wave morphological alterations,
while the PM-filtered atmosphere did not (Campen et al., 2006, 096879). Resuspended road dust
(PM25), at up to 3500 ug/m3 had no impact on ECG. For DE (PM mean concentration 512, 770, or
3,634 ug/m3; MMD 100 nm, CMD 80 nm; NOX mean concentration 19, 105, 102 ppm for low whole
exhaust, high PM filtered, and high whole exhaust, respectively), dramatic bradycardia, decreased
T-wave area, and arrhythmia (atrioventricular-node block and VPB) were only observed in mice
exposed to high filtered and high whole exhaust (Campen et al., 2005, 083977). These effects
remained after filtration of PM, suggesting that the gaseous components of the whole DE drove the
cardiovascular findings. The diesel- and gasoline-induced ECG changes contrast, in that the gasoline
exhaust required particles to induce T-wave changes, whereas the DE did not require PM to cause an
effect on ECG. However, the differing responses could be attributable to higher PM concentrations in
the whole DE.


      Summary of lexicological Study Findings for ECG Abnormalities

      The above toxicological studies demonstrate mixed results for arrhythmias, which may be
somewhat attributable to the different disease models used. Wellenius et al. (2004, 087874; 2006,
156152) showed decreased frequency of VPB and SVEB following PM2.5 CAPs exposure in rats
with induced MI (>12 h prior to exposure). One study reported increased frequency of premature
beats in older rats exposed to CAPs, which were not observed with UF carbon particles (Nadziejko
et al., 2004, 055632).  Rats with a MI model of CHF (3-mo recovery) had increased incidence of
VPB with DE exposure (Anselme et al., 2007, 097084). As for ECG morphology changes, T-wave
alterations were reported for gasoline exhaust that were absent when the PM was filtered (Campen
et al., 2006, 096879).  However, for DE, increased atrioventricular-node block, VPB, and decreased
T-wave area were observed with whole exhaust and remained after filtration of PM, indicating that
the gases were responsible for the effects (Campen et al., 2005, 083977).


6.2.3.  Ischemia

      Although no evidence from epidemiologic or controlled human exposure studies of PM-
induced myocardial ischemia was included in the 2004 PM AQCD (U.S.  EPA, 2004, 056905). one
toxicological study was cited that observed ST-segment changes in dogs following a 3-day exposure
to CAPs. In epidemiologic studies published since the 2004 PM AQCD (U.S. EPA, 2004, 056905).
associations have been demonstrated between PM and ST-segment depression, and one new
controlled human exposure study reported significant increases in exercise-induced ST-segment
depression among men with prior MI following a controlled exposure to DE. Results from recent
toxicological studies confirm the findings presented in the 2004 PM AQCD (U.S. EPA, 2004,
056905) and provide coherence and biological plausibility for the effects observed in epidemiologic
and controlled human exposure studies.


6.2.3.1.   Epidemiologic Studies


      ECG Changes Suggestive of Increased Ischemia

      The ST-segment duration is typically in the range of 0.08-0.12 s (80-120 ms). The direction of
the ST change is influenced by the extent of the acute myocardial injury.  If the ischemia or infarction
is transmural, i.e., penetrates the entire thickness of the ventricular wall, it usually causes ST-
segment elevation, while ischemia confined primarily to the ventricular endocardium often causes
ST-segment depression. Clinical ischemia is typically defined to include a downsloping ST segment
depression of >0.1 mV (ECG voltages are calibrated such that 1 mV equals 10 mm in the vertical
direction). The studies described below evaluate a range of ECG changes  suggestive of increased
December 2009                                 6-20

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ischemia including subclinical ST segment depressions (e.g. less than 0.1 mV or 1 mm) in relation to
ambient PM concentration.
      In a large study of the WHI Trial, Zhang et al. (2009, 191970) examined the change and risk of
subclinical ST-segment abnormalities, T-wave abnormalities, and T-wave amplitude associated with
ambient PM25 concentrations on the same and previous 6 days. Using logistic regression, each  10
(ig/m3 increase in the mean PM2 5, on lag days 0-2, was associated with a 4% (95% CI: -3 to 10)
increase in the relative odds of a ST-segment abnormality, and a 5% (95% CI: 0-9) increase in the
relative odds of a T-wave abnormality.
      Gold et al. (2005, 087558) studied 24 elderly residents of Boston, MA (aged 61-88 yr) residing
at or near an apartment complex that was -0.5 km from an air pollution monitoring station. A
protocol of continuous Holter monitoring including 5 min of rest, 5 min of standing, 5 min of
outdoor exercise, 5 min of rest, and then 20 cycles of paced breathing was done up to 12 times  for
each subject (n = 269 ECG measurements for analysis). From these ECG measurements, they
identified occurrences of ST-segment depression and examined whether mean BC, CO, and PM2 5
concentrations in the previous 5 and 12 h were associated with ST-segment depression. The median
5-h and 12-h mean BC concentrations were 1.28 and 1.14 (ig/m3, respectively (PM2.5 concentrations
are in Table 6-3). The mean BC concentrations in the 5 and 12 h before testing predicted ST-segment
depression in most portions of the protocol. However, these effects were strongest in the
post-exercise periods. For example, during the post-exercise rest period, each 10th-90th percentile
increase (1.59 (ig/m3) in the mean 5-h BC concentration was  associated with a -0.11 mm ST-segment
depression (95% CI: -0.18 to -0.05). In two pollutant models, CO did not appear to confound this
association. PM2 5 was not associated with ST-segment depression in this study. These findings
suggest traffic-generated particulate pollution may be associated with ST-segment depression.
      Previously, Pekkanen et al. (2002, 035050) conducted a panel study of 45 subjects with stable
coronary heart disease living in Helsinki, Finland. Each subject had biweekly sub-maximal exercise
testing for 6 mo (n = 342 exercise tests with 72 exercise-induced ST-segment depressions). The
median daily count of ACP (ACP: 0.1-1.0 (im) was 1,200 particles/cm3 (PM25  concentrations are
found in Table 6-3). They examined the risk of ST-segment depression associated with mean
pollutant concentrations (UFP, ACP, PMb PM2.5, PMi0_2.5, NO2, CO) in the previous 24 h, and the 3
previous  lagged 24-h periods. Each 7.9 (ig/m3 increase in mean PM25 concentration, lagged 2 days,
was associated with significantly increased risk of ST-segment depression >0.1 mV (OR: 2.84 [95%
CI: 1.42-5.66]). Each 760 particles/cm3 increase in the count of ACP, lagged 2  days, was also
associated with significantly increased risk of ST-segment depression >0.1 mV (OR: 3.29 [95%
CI: 1.57-6.92]). Similarly sized increased risks of ST-segment depression were also found for other
particulate pollutants, including PMi0_2.5, PMi, and UFP counts.
      This same research group, then conducted a principal components analysis to identify five
PM25 sources (crustal, long range transport, oil combustion, salt, and local traffic) (Lanki et al.,
2006, 088412). Using similar statistical models, each 1 (ig/m3 increase in "local traffic" particle
concentration, lagged 2 days, was associated with increased risk of ST-segment depression (OR: 1.53
[95% CI: 1.19-1.97]). Similarly, each 1 (ig/m3 increase in "long-range transport" particle
concentration was also associated with increased risk of ST-segment depression (OR: 1.11 [95%
CI: 1.02-1.20]). No significant associations for other sources were reported for any lag time.
      In Boston, Chuang et al. (2008, 155731) studied 48 patients with a prior percutaneous
intervention following MI, acute  coronary syndrome (ACS) without MI, or stable coronary artery
disease without ACS,. Each patient had a 24-h ECG measurement up to four times during study
follow-up. Using logistic regression, they estimated the risk of ST-segment depression of >0.1 mm,
during 30-min segments, associated with increases in the mean PM2 5, BC, CO, NO2, O3, and SO2
concentration in the previous 24 h. Each 6.93 (ig/m3 increase in mean PM25 concentration was
associated with a significantly increased risk of ST-segment depression (OR =  1.50 [95% CI:
1.19-1.89]). Using linear additive models to estimate the change in ST level associated with the same
PM2.5 change, they observed a significant -0.031 mm change (95% CI: -0.042 to -0.019). In single
pollutant models, risk estimates were of similar magnitude and statistically significant for BC, NO2,
and SO2.  In two pollutant models, however, PM25 risk estimates were reduced to 1.0 in all models
with BC, NO2, and SO2. In contrast, the risk estimates for BC, NO2,  and SO2 remained elevated and
statistically significant when modeled with PM2 5.
      In a panel study of 14 Helsinki resident, non-smoking,  elderly subjects with coronary artery
disease, Lanki et al. (2008, 191984) used logistic regression to report that  each 10 (ig/m3 increase in
personal PM2 5 concentration in the previous hour was associated with a significantly increased risk
December 2009                                  6-21

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of ST-segment depression (OR = 3.26 [95% CI: 1.07-9.98]). In addition, each 10 ug/m3 increase in
outdoor mean PM2 5 concentration in the previous 4 h was also associated with an increased risk (OR
= 2.47 [95% CI: 1.05-5.85]). Last, the risk estimates for all time lags examined (1, 4, 8, 12, and 22 or
24 h) for all PM size fractions were increased, but none other than those described above were
statistically significant.


      Summary of Epidemiologic Study Findings for Ischemia

      These studies demonstrate associations between PM2.5 pollution and ST-segment depression at
lags of 1 h-2 days. Moreover, these findings demonstrate a potential role for traffic (Chuang  et al.,
2008, 155731: Gold et al., 2005, 087558) and long-range transported PM2.5 (Lanki  et al., 2006,
089788). Mean and upper percentile concentrations reported in these studies are found in Table 6-3.
Table 6-3.    PM Concentrations reported in epidemiologic studies ECG changes suggestive of
             ischemia.
           Author
      Location
 Mean Concentration (ug/m3)
     Upper Percentile
   Concentrations (ug/m3
PM2.5
Zhang etal. (2009,191970)
PMiO-2.5
Mulitcity, US:WHI Clinical Trial NR
                                                                      NR
Pekkanen et al. (2002, 035050) Helsinki, Finland
Gold et al. (2005. 087558) Boston, MA
Chuang et al. (2008, 155731) Boston, MA
Lanki et al. (2008, 191984) Helsinki, Finland
24-havg: 10.6 (median)
5-havg:9.5 (median)
12-havg:9.8 (median)
12-havg:9.91 (median)
24-havg: 9.20 (median)
Personal
1-havg:11.5(median)
4-havg: 10.1 (median)
22-havg:9.3 (median)
Outdoor
24-havg: 12.5
75th: 16.0
Max: 39.8
5-havg 90th: 25.6 Max: 41.0
12-havg 90th: 25.9 Max: 35.6
12-havg75th:13.18
24-havg max: 40. 38
Personal
1-havg 75th: 17.2; Max: 746.3
4-havg 75th: 15.7; Max 189.6
22-havg 75th: 13.2; Max 52.9
Outdoor
24-havg 75th: 17.7; Max: 30.5
Pekkanen et al. (2002, 035050)
Helsinki, Finland
24-havg:4.8 (median)
75th:8.5

Max: 37.0
6.2.3.2.   Controlled Human Exposure Studies
      Diesel Exhaust

      Among a group of 20 men with prior MI, Mills et al. (2007, 091206) found that DE
(300 ug/m3 particle concentration, median particle diameter 54 nm) significantly increased
exercise-induced ischemic burden during exposure, calculated as the product of exercise duration
and change in ST-segment amplitude. The mechanism by which DE induced the exacerbation of
ischemic burden remains unclear, and appears to be unrelated to impaired vasodilation. However, the
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authors suggest that this discrepancy may be due to the timing of the vascular assessment, as
measures of blood-flow were taken 5 h after the observed increase in ischemic burden. Although it is
reasonable to assume that the observed increase in ST-segment depression during exercise represents
an increased magnitude of ischemia, it is important to note that there are other potential explanations
for the ST change. For example, it is possible that the ST-segment depression could be secondary to
heterogeneity of electrophysiological responses of particle exposure on the myocardium that is
enhanced by the metabolic and ionic conditions associated with ischemia or increased HR.  It is also
important to note that the effects observed in this study cannot be conclusively attributed to the
particles per se, as subjects were also exposed relatively high levels of NO (3.45 ppm), NO2
(1.01 ppm), CO (2.9 ppm), and total hydrocarbons (2.8 ppm).


6.2.3.3.   lexicological Studies



      CAPs

      A study that examined ECG changes in dogs (female; retired mongrel breeder dogs) following
PM2.5 CAPs exposure in Boston, MA (mean mass concentration 345 ug/m3; 9/2000-3/2001) and left
anterior descending coronary artery occlusion as an indicator of myocardial ischemia reported
changes in ST-segment (Wellenius  et al., 2003, 055691). The experimental protocol was a  6-h
exposure to CAPs via tracheostomy, followed by a preconditioning occlusion (5 min), rest interval
(20 min), and the experimental occlusion (5 min). Increased ST-segment elevation was observed
following PM2.5 during the experimental occlusion period compared to filtered air. Furthermore,
peak ST-segment elevation attributable to CAPs was reported with the experimental occlusion,
which remained elevated 24 h post-exposure.  Ventricular arrhythmias were rarely observed during
occlusion and when observed, were unrelated to CAPs exposure. The results from this study support
those previously observed (Godleski et al., 2000, 000738) and provides greater support that
enhanced myocardial ischemia occurs relatively quickly (within hours) following PM exposure.
      The Wellenius et al. (2003, 055691) study also attempted to link ST-segment changes with
four CAPs elements (Si, Ni, S, and BC) as tracers of PM2.5 sources in Boston. In the multivariate
regression analyses, peak ST-segment elevation and integrated ST-segment change were significantly
associated with only the mass  concentration of Si (Si mean concentration 8.17 ug/m3; Si
concentration 2.31-13.93 ug/m3). In the univariate regression analyses, Pb also demonstrated a
significant association for both ST-segment measures,  although the p-value was greater than that
observed with Si.
      A recent study in dogs (female mixed-breed canines) evaluated myocardial blood flow during
myocardial ischemia following 5-h PM2 5 Boston CAPs exposures  (daily mean mass concentration
94.1-1556.8 ug/m3; particle number concentration 3-69.3><103 particles/cm3; BC concentration
1.3-32.0 ug/m ) (Bartoli et al., 2009, 179904). Similar methods were used for the coronary
occlusion and exposure method as Wellenius et al. (2003,  055691). Immediately following  exposure,
microspheres were injected (15 urn diameter) into the left atrium after 3 min of ischemia during the
second occlusion. Post-mortem analysis of cardiac tissue and blood samples allowed for
quantification of microspheres. CAPs-exposed dogs had decreased total myocardial blood flow and
increased coronary vascular resistance during occlusion that was greatest in tissue within or near the
ischemic zone. The rate-pressure product (product of HR and SBP) during occlusion was unchanged
in animals exposed to CAPs, indicating that cardiac metabolic demand was not altered. The
multilevel linear mixed models demonstrated that myocardial blood flow and coronary vascular
resistance during occlusion were inversely and significantly associated with CAPs mass
concentration, particle number concentration, and BC concentration, with the strongest effects
observed with particle number concentration.  The results of this study provide evidence that
exacerbation of myocardial ischemia following PM exposure is due to reduced myocardial  blood
flow, perhaps via dysfunctional collateral vessels.
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      Intratracheal Instillation

      Cozzi et al. (2006, 091380) exposed ICR mice to UF PM (100 (ig IT instillation), followed by
ischemia/reperfusion injury to the left anterior coronary artery 24 h later. The area-at-risk (the region
of tissue perfused by the left anterior descending coronary artery) and the infarct size were measured
2 h following reperfusion, and while the area-at-risk was not affected by PM exposure, the infarct
size was nearly doubled in mice who received UF PM. Increases in infarct size were associated with
increased myocardial neutrophil density in the infarct zone and lipid peroxidation in the
myocardium.


      Summary of lexicological Study Findings for Ischemia

      The studies described above provide evidence that PM can induce greater myocardial
responses following ischemic events, as demonstrated by, enhanced ischemia, decreased myocardial
blood flow and increased coronary vascular resistance, and increased infarct size.


6.2.4.  Vasomotor Function

      The most noteworthy new cardiovascular-related revelation in the past six years with regards
to PM exposure is that the systemic vasculature may be a target organ. The vasculature of all tissues
is lined  with endothelial cells that will naturally encounter any systemically absorbed toxin. The
endothelium (1) maintains barrier integrity to ensure fluid compartmentalization; (2) communicates
dilatory and constrictive stimuli to vascular smooth muscle cells; and (3) recruits inflammatory cells
to injured regions. Smooth muscle cells lie within the layer of endothelium and are crucial to the
regulation of blood flow and pressure. In states of injury and disease, both cell types can exhibit
dysfunction and even pathological responses.
      Endothelial dysfunction is a factor in many diseases and may contribute to the origin and/or
exacerbation of perfusion-limited diseases, such as MI or IHD, as well as hypertension. Endothelial
dysfunction is also a characteristic feature of early  and advanced atherosclerosis. A primary outcome
of endothelial dysfunction is impaired vasodilatation, frequently due to uncoupling of NOS. It is this
uncoupling that appears central to impaired vasodilation and thus endothelial dysfunction.
      One controlled human exposure study cited in the 2004 PM AQCD (U.S. EPA, 2004, 056905)
reported a decrease in bronchial artery diameter (BAD) among healthy adults following exposure to
CAPs in combination with O3. Conclusions based on this finding were limited due to the
concomitant exposure to O3 as well as a lack of published results from epidemiologic and
toxicological studies. Recent controlled human exposure studies have provided support to the
findings described in the 2004 PM AQCD (U.S. EPA, 2004, 056905). with changes  in vasomotor
function observed following controlled exposures to DE and EC particles. In addition, epidemiologic
studies have observed associations between PM and decreases in BAD and flow  mediated dilatation
(FMD) in healthy adults and diabetics. These findings are further supported by a large body of new
toxicological evidence of impaired vasodilation following exposure to PM.


6.2.4.1.   Epidemiologic Studies

      O'Neill et al. (2005, 088423) examined the association between 2 measures of vascular
reactivity, non-endothelium dependent nitroglycerin mediated reactivity and endothelium-dependent
flow-mediated reactivity,  and ambient mean particulate pollutant concentration (PM2.5, SO42~, BC,
PNC) on the same and previous few days. They studied a panel of 270 subjects with diabetes or at
risk for  diabetes, who lived in the greater Boston metropolitan area. Using linear regression models,
the change in vascular reactivity associated with moving average pollutant concentrations across the
same and previous 5 days was estimated. Interquartile range (values not reported) increases in mean
PM2.5 concentration, BC concentration, and PNC over the previous  6 days were associated with
decreased vascular reactivity among diabetics, but not among subjects at risk for diabetes. For SO42~,
the mean concentration on lag day 0, lag day 1, and the 3-day, 4-day, and 5-day ma all were
associated with similarly sized reductions in both metrics of vascular reactivity. Among diabetics,
each interquartile range increase in the mean SO42~ concentration over the previous 6 days was
December 2009                                  6-24

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associated with a 5.4% decrease in nitroglycerin-mediated reactivity (95% CI: -10.5 to -0.1) and
flow-mediated reactivity (-10.7% [95% CI: -17.3 to -3.5]). Also among diabetics, each interquartile
range increase in the mean PM2.5 concentration over the previous 6 days was associated with a 7.6%
decrease in nitroglycerin-mediated reactivity (95% CI: -12.8 to -2.1) and anon-significant 7.6%
decrease in flow-mediated reactivity (95% CI: -14.9 to 0.4). Each interquartile range increase in the
mean BC concentration over the previous 6 days was associated with a 12.6% decrease in flow
mediated reactivity (95% CI: -21.7 to -2.4), but not nitroglycerin-mediated reactivity. PNC  was
associated with non-significant decreases in both measures. Effect estimates were larger for type 2
diabetics than type 1 diabetics.
      Dales et al. (2007, 155743) conducted a panel study of 39 healthy volunteers who sat at 1 of 2
bus stops in Ottawa, Canada for 2 h. FMD of the brachial artery was measured immediately after the
bus stop exposure, but not before. They examined the association between FMD and 2-h mean
PM2.5, PMi, NO2, and traffic density at the bus stop (vehicles/h). The authors report that each
30 ug/m3 increase in 2-h mean PM2.5 concentration was associated with a significant 0.48%
reduction in FMD. This represented a 5% relative change in the maximum ability to dilate.
      This same research group conducted a panel study of 25 type 1 or 2 diabetic subjects living in
Windsor, Ontario (aged 18-65 yr) (Liu et al., 2007, 156705). For each subject, personal PMi0
concentrations were measured for 24 h before measurements of BAD, FMD, and other biomarkers.
Each 10 ug/m3 increase in personal 24-h mean PM10 concentration was associated with a 0.20%
increase in end-diastolic FMD (95% CI:  0.04-0.36) and a 0.38% increase in end-systolic FMD (95%
CI: 0.03-0.73), but decreases in end-diastolic basal diameter (-2.52 urn [95% CI: -8.93 to 3.89]) and
end-systolic basal diameter (-9.02 urn [95% CI: -16.04 to -2.00]).
      Rundell et al.  (2007, 156060) examined the change in FMD associated with high and low PMi
(0.02-1.0 urn) pollution in a panel of 16 young intercollegiate athletes (mean age = 20.5±2.4 yr) in
Scranton, PA, who were non-smokers, non-asthmatics, and free of cardiovascular disease (Rundell
et al., 2007,  156060). Each subject had FMD of the brachial artery measured 10-20 min before and
20-30 min after each of two 30-min exercise tests (85-90% of maximal HR). The exercise tests were
done outside either on an inner campus location free of automobile and truck traffic (low PMi;
mean = 5,309±1,942 particles/cm3) or on a soccer field adjacent to a major highway (high PMi;
mean = 143,501±58,565 particles/cm3). The order of the exercise test locations was chosen
randomly. Using paired t-tests for analysis, they reported FMD was impaired after high PM:
exposure (pre-exercise: 6.8±3.58%; post-exercise:  0.30±2.74%), but not low PMi exposure
(pre-exercise: 6.6±4.04%; post-exercise: 4.89±4.42%). Further, they found basal brachial artery
vasoconstriction (4%; pre-exercise BAD: 4.66±0.61 mm; post-exercise BAD: 4.47±0.63 mm) after
the 'high PM/ exposure, but not the 'low PMi' exposure (-0.3% pre-exercise BAD: 4.66±0.63 mm;
post-exercise BAD:  4.68±0.61 mm).
      In a prospective panel study of 22 type 2 diabetics (aged 61 ± 8 yr), Schneider et al. (2008,
191985) examined the change in FMD, BAD, small artery elasticity index, larger artery elasticity
index, and systemic vascular resistance associated  with ambient PM2 5 as measured in Chapel Hill,
NC (November 2004-December 2005). Using additive mixed models with a random subject effect,
each 10 ug/m3 increase in PM25 in the previous 24 h was associated with a decrease in FMD (-
17.3% [95% CI: -34.6 to 0.0]). Similarly, each 10 ug/m3 increases in PM25 was associated with a
decrease in small artery elasticity index lagged 1 day (-15.1% [95% CI: -29.3 to -0.9]), and lagged 3
days (-25.4% [95% CI: -45.4 to -5.3]). Significant  decreases in larger artery elasticity index and
increases in  systemic vascular resistance lagged 2 and 4 days were also reported. Further, effects
were greatest among those with high BMI, high glycosylated hemoglobin Ale, low adiponectin, or
the null GSTM1 polymorphism. However, high myeloperoxidase (MPO) levels were associated with
greater PM2 5 effects on these measures.
      In a similar study done in Paris, France, Briet (2007, 093049) similarly reported that  each
increase in PM25 was associated with a -0.32% decrease in FMD (95% CI: -1.10 to 0.46). Significant
FMD reductions were associated with increased SO2, NO2, and CO concentrations. Each 1  standard
deviation increase (units not given) in PM25 in the previous 2 wk was associated with a 15.68%
(95% CI: 7.11-23.30) increase in small artery reactive hyperemia. Each 1 standard deviation increase
(units not given) in PMi0 in the previous 2 wk was associated with a 15.91% (95% CI: 7.74-24.0)
increase in small artery reactive hyperemia.
December 2009                                  6-25

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      Summary of Epidemiologic Study Findings for Vasomotor Function

      Vasomotor function has been evaluated using several metrics in the studies described above,
including FMD, small artery elasticity index, larger artery index, systemic vascular resistance, BAD,
end diastolic basal diameter, and nitroglycerin-mediated reactivity. The most common measures
evaluated were BAD, a measure of the relatively static, anatomic/physiological baseline vasomotor
function, and FMD, the dynamic measure of post- minus pre-occlusion BAD. Each study
demonstrated an acute association between these measures of vascular function and ambient PM25
concentrations (Briet et al., 2007, 093049: Dales  et al., 2007, 155743: Liu  et al., 2007, 156705:
O'Neill  et al., 2005, 088423: Rundell et al., 2007, 156060: Schneider et al., 2008, 191985). An
association with PM10 was observed in a study conducted in Windsor Ontario (Liu et al., 2007,
156705). Three studies evaluated effects on diabetics (Liu et al., 2007, 156705: O'Neill et al., 2005,
088423: Schneider et al., 2008, 191985). and three evaluated PM-related changes in vasomotor
function on young healthy subjects (Briet et al., 2007, 093049: Dales  et al., 2007, 155743: Rundell
et al., 2007, 156060). Only two studies investigated multiple lags (lag days 0 to 6) (O'Neill et al.,
2005, 088423: Schneider  et al., 2008, 191985).  with one reporting the strongest association with the
6-day mean PM concentration (O'Neill et al., 2005,  088423). and the other with lag day 0. In other
studies, responses were observed in as short as 30 min after the exposure (Rundell et al., 2007,
156060). The Rundell et al. (2007, 156060) findings are consistent with other studies showing an
adverse response to ambient particulate pollution emitted from vehicular traffic (Adar et al., 2007,
098635: Adar et al., 2007, 001458: Riediker  et al., 2004, 056992: Riediker  et al., 2004, 091261).
Mean and upper percentile concentrations reported in these studies are found in Table 6-4.
Table 6-4.     PM concentrations reported in epidemiologic studies of vasomotor function.
Author
Location
Mean Concentration (ug/m3)
Upper Percentile
Concentrations (ug/m )
PM2.5
Briet (2007, 093049)
Dales (2007, 155743)
O'Neill (2005, 088423)
Schneider (2008. 191 985)
Paris, France
Ottawa, Canada (bus stops)
Boston, MA
Chapel Hill, NC
NR
Bus stop 1 : 40
Bus stop 2: 10
11.5
13.6
NR
NR
Range: 1.1 -20.0
NR
PM10
Briet (2007, 093049)
Liu (2007. 156705)
Paris, France
Windsor, Ontario
NR
24h (personal): 25.5
NR
5th to 95th: 9.8 -133
6.2.4.2.   Controlled Human Exposure Studies

      Some evidence of a PM-induced increase in brachial artery vasoconstriction is presented in the
2004 PM AQCD (U.S. EPA, 2004, 056905). Brook et al. (2002, 024987) exposed 24 healthy adults
to PM2.5 CAPs (150 ug/m3) along with 120 ppb O3 for a period of 2 h. A significant decrease in BAD
was observed immediately following exposure compared with filtered air control. No significant
changes were observed in either endothelial-dependent or endothelial-independent vasomotor
function, as determined by FMD and nitroglycerin-mediated dilatation, respectively. As described
below, many more recent studies have evaluated the effects of various types of particles on
vasomotor function following controlled exposures among healthy and health-compromised
individuals.
December 2009
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      CAPS

      A subsequent analysis of the CAPs constituents from the Brook et al. (2002, 024987) study
revealed a significant negative association between the post-exposure change in BAD and both the
OC and EC concentrations of CAPs (Urch  et al., 2004, 055629). However, the observed vasomotor
effects cannot conclusively be attributed to PM2.5, as subjects were exposed concurrently to PM2.5
and O3. Mills et al. (2008,  156766) evaluated the effect of fine and UF CAPs on vasomotor function
in a group of 12 males with stable coronary heart disease (average age 59 yr), as well as in 12
healthy males (average age 54 yr). Relative to filtered air exposure, exposure to PM (average
concentration 190 ug/m3) did not significantly affect vascular function in either group. The authors
attributed the lack of response in endothelial function to  the composition of the CAPs used in the
study, which were low in combustion-derived particles and consisted largely of sea salt.


      Urban Traffic Particles

      The effect of exposure to urban traffic particles on vasomotor function has recently been
evaluated among a group of adult volunteers (Brauner et al., 2008,  191966). In this study, healthy
young adults  (average age 27 yr) exposed for 24 h to urban traffic particles (average PM2.5
concentration 10.5 ug/m )  were not observed to experience any change in microvascular function
after 6 or 24 h of exposure relative to filtered air.


      Diesel Exhaust

      Mills et al. (2005, 095757) exposed 30 healthy men (20-38 yr) to both diluted DE (300 ug/m3)
and filtered air control for  1 h with intermittent exercise. Half of the subjects underwent vascular
assessments at 6-8 h following exposure to DE or filtered air, while in the other 15 subjects, vascular
assessments were performed at 2-4 h post-exposure. DE attenuated forearm blood flow increase
induced by bradykinin, acetylcholine (ACh), and sodium nitroprusside (SNP) infusion measured 2
and 6 h after exposure.  The authors postulated that the effect of DE on vasomotor function may be
the result of reduced NO bioavailability in the vasculature stemming from oxidative stress induced
by the nanoparticulate fraction of DE. A DE-induced decrease in the release of tPA was also
observed at 6 h post-exposure, which may provide additional mechanistic evidence supporting the
observed association between air pollution and MI. As presented in Tornqvist et al. (2007, 091279).
changes in vascular function were also evaluated 24 h following exposure in 15 of the 30 subjects.
Compared with filtered air, exposure to DE significantly reduced endothelium-dependent (ACh)
vasodilation at 24 h post exposure. Bradykinin-induced vasodilation was marginally attenuated by
DE, while no effects of diesel on endothelium-independent vasodilation (SNP) were observed.
Although the release of tPA was not affected by DE 24 h following exposure, the authors  suggest
that the persistent association  between diesel  exposure and vasomotor function observed in this study
provides supporting mechanistic evidence of increases in cardiovascular events occurring 24 h after
a peak in PM concentration.
      To further investigate the effects of DE on vasomotor function, Mills et al.  (2007, 091206)
exposed 20 men (avg age 60 yr) with previous MI on two separate occasions to dilute DE
(300 ug/m3; mean particle  size 54 nm) or filtered air for  1 h with intermittent exercise. Contrary to
previous findings in younger,  healthy adults (Mills et al., 2005, 095757). DE was found not to affect
vasomotor function in peripheral resistance vessels at 6 h post-exposure as measured by
endothelium-dependent (ACh) and endothelium-independent (SNP) vasodilation (forearm blood
flow).  However, vascular assessments were not performed at 2 h post-exposure in this study. The
same laboratory evaluated the effect of exposure to DE with slightly higher particle concentrations
(330 ug/m3, particle number 1.26xl06/cm ) on arterial stiffness among healthy adults (Lundback et
al., 2009, 191967). Using radial artery  pulse wave analysis, significant increases in augmentation
pressure and augmentation index, as well as a significant reduction in the time to wave  reflection
were observed 10 and 20 min  following exposure to DE relative to filtered air. This finding of a DE-
induced reduction in arterial compliance provides additional evidence to suggest that exposure to
particles may adversely affect vasomotor function.
December 2009                                  6-27

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      Peretz et al. (2008, 156854) exposed both healthy adults (n = 10) and adults with metabolic
syndrome (n = 17) for 2 h to filtered air and two concentrations of diluted DE (PM2.5 concentrations
of 100 and 200 ug/m3). Compared with filtered air, DE at 200 ug/m3 elicited a statistically significant
decrease in BAD (0.11 mm [95% CI: 0.02-0.18 mm]) immediately following exposure. A smaller
DE-induced decrease in BAD (0.05 mm) was observed following exposure to 100 ug/m3. Although
this latter decrease was not statistically significant, the average decrease was approximately 50% of
the decrease at the higher particle concentration, which provides suggestive evidence of a linear
concentration response in this range of concentrations. Exposure to DE was not shown to
significantly affect endothelium-dependent FMD. Plasma levels of endothelin-1 (ET-1) were
observed to increase relative to filtered air exposure approximately 1 h after exposure to 200 ug/m3
DE (p = 0.01). Samples collected following the 100 ug/m3 exposure session were not assayed for
ET-1. The results of this study provide evidence of an acute endothelial response and arterial
vasoconstriction resulting from short-term exposure to DE. DE-induced changes in vasoconstriction
and ET-1 release were more pronounced in the healthy subjects than in the subjects with metabolic
syndrome. The authors postulated that subjects with metabolic syndrome may have stiffer vessels
that are not as responsive to vasoconstrictor stimuli. In a study utilizing a similar exposure protocol,
Lund et al. (2009, 180257) observed a significant increase in ET-1 in healthy adults following a 2-h
exposure to DE with a particle concentration of 100 ug/m3.
      In the previously described studies by Mills et al. (2005, 095757; 2007, 091206). Peretz et al.
(2008, 156854). Tornqvist et al. (2007, 091279) and Lund et al. (2009, 180257). subjects were
exposed to DE, which, in addition to PM, includes DE gases such as NOX, CO, and hydrocarbons.
Therefore, it is possible that the observed effects may be due in part to exposure to non-particle
components of DE. While the majority of these DE exposures have contained relatively high levels
of gaseous emissions including NO2 concentrations >2 ppm, the concentrations of these gases were
much lower in the Peretz et al. (2008, 156854) study (NO2 concentrations ~ 20 ppb) which used a
newer diesel engine (2002 Cummins B-series) operating under load at 75% of rated capacity. In this
study, an apparent linear concentration response relationship was observed between increasing DE
exposure and decreases in BAD at particle concentrations between 100 and 200 ug/m3.


      Gasoline Emissions

      Rundell and Caviston (2008, 191986) exposed 15 college athletes to particles generated using
a 2.5 hp gasoline engine, as well as a clean air control during 6-min periods of maximal exercise on a
cycle ergometer. Subjects were exposed twice under each condition, with the two clean air exposures
occurring first, separated by 3 days. The 2 exposures to gasoline emissions were also separated by
3 days, with the first exposure occurring 7 days after the second clean air exposure. During
exposures to gasoline emissions, average PNC of PM <1.0 urn were reported as 336,730 and
396,200 particles/cm3  during the first and second  exposures, respectively, with an average CO
concentration of 6.3 ppm. There were no differences observed in total work done (kJ) over the 6-min
exercise periods between the two clean air exposures or between the clean air exposures and the first
exposure to gasoline exhaust. However, the second gasoline exhaust exposure was demonstrated to
significantly decrease  work accumulated over the 6-min exercise period compared with either of the
other exposure conditions. The results of this  study provide limited evidence to suggest that a very
short term exposure to gasoline emissions may affect exercise performance in healthy adults. The
authors speculated that the observed effect of exposure on work accumulated during maximal
exercise could be due to vasoconstriction and decrease in blood flow in the skeletal muscle
microcirculation. However, the effect of exposure on vasoreactivity was not explicitly assessed.


      Model Particles

      The results of a recent study by Shah et al. (2008, 156970) provides evidence that exposure to
UF EC particles (50 ug/m3) without coexposure to organics, metals, or gaseous copollutants may
alter vasomotor function in healthy adults. In  this study, venous occlusion plethysmography was
used to measure reactive hyperemia of the forearm prior to exposure, immediately following
exposure, and 3.5 h, 21 h, and 45 h following a 2-h exposure with intermittent exercise. Peak
December 2009                                  6-28

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forearm blood flow was observed to increase after exposure to filtered air, but not following
exposure to UF EC at 3.5 h post-exposure (p = 0.03).


      Summary of Controlled Human Exposure Study Findings for Vasomotor Function

      Taken together, the two studies by Mills et al. (2005, 095757; 2007, 091206) along with the
studies by Peretz et al. (2008, 156854). Lund et al. (2009,  180257) and Tornqvist et al. (2007,
091279) suggest that, in healthy subjects, DE exposure inhibits endothelium-dependent and
endothelium-independent vasodilation acutely (within 2-6 h), and that the suppression of
endothelium-dependent vasodilation may remain up to 24  h following exposure. In patients with
coronary artery disease, vasodilator function does not appear to be affected 6-8 h following
exposure; however, vascular assessments were not performed at earlier time points. In addition, the
use of medications in these patients may have blunted the  response to PM. The findings of Shah
et al. (2008,  156970) suggest that UFP carbon core may be sufficient to produce small changes in
systemic vascular function, but the mechanisms remain obscure. The authors demonstrated a
decrease in nitrate levels following exposure to UF EC; however, venous nitrite level, which more
closely reflects NO production, was unchanged. Exposure to urban traffic particles was not
demonstrated to alter vasomotor function among healthy adults.


6.2.4.3.   lexicological Studies

      Vascular dysfunction is a function of altered production of vasoconstrictors and vasodilators.
In the 2004 PM AQCD (U.S. EPA, 2004, 056905). studies examining ET as an activator of
vasoconstriction were limited to those conducted by Bouthiller et al. (1998, 087110) and Vincent
et al. (2001,  021184). in which increased plasma ET levels were observed in rats exposed to high
concentrations (40 or 5 mg/m3) of resuspended Ottawa (EHC-93) or diesel PM, respectively. The
authors postulated that PM altered vasoconstriction via elevated ET. No studies were cited in the
2004 PM AQCD (U.S. EPA, 2004, 056905) that looked at direct measures of vasoreactivity.
      As this area is newly emerging, some studies are included below that utilize IT exposure or
high concentrations; the studies that exposed vessels directly to particles ex vivo are included in
Annex D only, as their relevance is questionable. There is  clearly a need for more toxicological
research examining the relationship between vascular measurements and PM exposures using
ambient particles at lower concentrations. Furthermore, no new studies have advanced the
knowledge in regards to ET as a biomarker of PM-induced vasoconstriction since the last PM
review.


      CAPS

      SD rats were exposed to PM2.5 CAPs (5 h/day><3 days; daily mean mass concentration
73.5-733 ug/m3; Boston, MA; 3/1997-6/1998) then the pulmonary arterial vasculature was evaluated
(Batalha et al., 2002, 088109).  Some animals were repeatedly exposed to SO2 (5 h/day><5
days/wk><6 wk) to induce chronic bronchitis. Morphometric measurements indicated that the
pulmonary artery lumen-to-wall (L/W) ratio (an indicator  of arterial narrowing) was decreased for
the  both CAPs groups compared to the normal/air group. Furthermore, decreased L/W ratio in
CAPs-exposed animals (regardless of pre-treatment) was significantly associated with particle mass
and composition when the mean concentrations from the second and third exposure days were used
in a univariate linear regression. These results indicate a change in vascular tone following acute
exposure to PM. Univariate analyses were conducted that regressed log L/W on differential exposure
concentrations of tracer elements  determined using principal components analysis (Batalha et al.,
2002, 088109). For CAPs exposure (regardless of pretreatment), CAPs mass, Si, Pb, SO42~, EC, and
OC were all negatively correlated with L/W ratio. Si and SO42~ were negatively correlated with L/W
ratio in normal rats and Si and OC were negatively correlated with L/W ratio in bronchitic rats.
When a multivariate analysis was conducted using normal and bronchitic animals, only the
association with Si remained significant. V was not associated with L/W ratio in any analysis.
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      Diesel Exhaust

      The venous circulation plays a prominent role in heart failure exacerbation (Gehlbach and
Geppert, 2004, 155784). In heart failure, patients are often volume overloaded and are subsequently
placed on diuretics to alleviate symptoms of pulmonary congestion and chest pain. Knuckles et al.
(2008, 191987) hypothesized that if veins constrict in a manner similar to arteries, then patients with
severe CHF may have temporary shunting of fluid to the pulmonary circulation, which may elicit
signs and symptoms of CHF. Using mesenteric vessels from mice (C57BL/6) exposed to DE
(350 ug/m  x4 h;  MMD 100 nm, CMD 80 nm), the authors reported a significant enhancement of
ET-1-induced vasoconstriction in veins with much weaker responses in arteries. In an ex vivo
experiment, venous constriction was blocked by the  arginine analog, L-NAME, which eliminates the
feedback NOS activation via endothelial ETB receptors; this is indicative of impaired or uncoupled
eNOS. The authors hypothesized that volatile organic compounds might be responsible these effects,
but no significant effects were observed for acetaldehyde, formaldehyde, acetone, hexadecane, or
pristane.


      Model Particles

      A study by Nurkiewicz et al. (2008,  156816) compared the arteriole dilation responses in the
spinotrapezius muscle with inhalation exposure to fine or UF TiO2 (1 urn and 21 nm, respectively;
mean mass concentration 3-16 and 1.5-12 mg/m3, respectively) for durations of 4-12 h in SD rats.
Both size fractions of TiO2 induced impaired dilation with a NO-dependent Ca2+ ionophore in a
dose-dependent manner. When fine and UF TiO2 were compared at similar mass doses, the systemic
microvascular dysfunction was greater with the UFPs. Furthermore, three exposures of differing
durations and concentrations that produced equal calculated pulmonary deposition of UF TiO2
(30 ug) demonstrated similar dilation responses, indicating that impairment is dependent upon the
timexconcentration product. No effects on dilation were observed with a dose of 4 ug UF TiO2
(1.5  mg/m3 for 4 h) or 8 ug fine TiO2 (3 mg/m3 for 4 h).
      In a follow-up study, Nurkiewicz et al. (2009,  191961)  examined the effect of pulmonary fine
and UF TiO2  exposure on endogenous microvasculature NO production in SD rats. The exposure
concentrations and durations were selected to produce -50% impairment of microvascular reactivity
(67 and 10 ug for fine1 and UF2 TiO2, respectively).  Similar to the study above (Nurkiewicz et al.,
2008, 156816). impaired endothelium-dependent arteriolar dilation was observed 24 h post-exposure
with infusion of a Ca2+ ionophore. Earlier studies that used residual oil fly ash (ROFA) or TiO2 via
IT instillation reported similar findings, regardless of particle type (Nurkiewicz  et al., 2004, 087968;
Nurkiewicz et al., 2006, 088611). There was no difference in arteriolar dilation between sham and
TiO2 exposed groups with direct administration of the NO donor SNP to the exterior arteriolar wall
and this response was  consistent with that observed following ROFA administered intratracheally
(Nurkiewicz  et al., 2004, 087968). The lack of response to SNP indicates that vascular smooth
muscle sensitivity to NO is not altered after particle  exposure. The amount of ROS in the
microvascular wall was increased following exposure to either TiO2 size. Local  ROS may consume
endothelial-derived NO and generate peroxynitrite radicals, as microvascular nitrotyrosine (NT)
formation (the end product of peroxynitrite reactions) was demonstrated after TiO2 exposure. NO
production was compromised in a dose-dependent manner following particle exposure (8-90 ug for
fine  and 4-38 ug for UF TiO2), and was partially restored with agents for radical scavenging or
enzyme inhibition for NADPH oxidase and MPO.


      Intratracheal Instillation

      Nurkiewicz et al. (2004, 087968: 2006, 088611) have shown impairment of
endothelium-dependent dilation in the systemic microvasculature of SD rats following ROFA or
TiO2 exposure (0.1 or  0.25 mg/rat). NO-independent arteriolar dilation was also impaired by ROFA,
1 Produced by a 300-min exposure to 16 mg/m3 of fine TiO2

2 Produced by a 240-min exposure to 6 mg/m3 of ultrafine TiO2



December 2009                                 6-30

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but arteriole adrenergic sensitivity to phenylephrine (PHE) was not affected by 0.25 mg ROFA,
indicating that contractile activity was unchanged. In addition, increased venular leukocyte rolling
and adhesion in the spinotrapezius muscle was also observed following ROFA exposure (Nurkiewicz
etal.. 2004. 0879681
      Further characterization of the leukocyte adherence and "rolling" effects for both ROFA and
TiO2 were indicative of an activated endothelium (Nurkiewicz  et al., 2006, 088611). Vascular
deposition of MPO was observed in the spinotrapezius muscle 24 h post-exposure and the authors
suggested that the adherent leukocytes may have deposited the MPO to be taken up by endothelial
cells (Nurkiewicz  et al., 2006, 088611). However, this is in contrast to another study (Cozzi  et al.,
2006, 091380) that did not find changes in blood neutrophil MPO release in ICR mice exposed to
UF PM (100 ug from Chapel Hill, NC; assessed 24 h post-exposure), although this finding may be a
reflection of differing protocols. Increased oxidative stress in the arteriolar wall was also reported
with exposure to 0.25 mg ROFA. TiO2 and ROFA induced varying degrees of pulmonary
inflammation in these animals, but elicited very similar vascular effects, indicating that the vascular
responses may be due to PM presence in the lung rather than its physiochemical properties or
intrinsic pulmonary toxicity.

      PM10

      Tamagawa et al. (2008, 191988) reported reduced ACh-stimulated relaxation in carotid arteries
from rabbits (New Zealand White) exposed to PMi0 (EHC-93) via intrapharyngeal instillation for 5
days or 4 wk (total doses 8 and 16 mg/kg, respectively). Endothelium-dependentNO-mediated
vasorelaxation correlated with increased serum IL-6 levels in the acute study and during wk 1 and 2
of the 4-wk exposure, which may indicate a role for systemic inflammation in the response. Maximal
SNP-induced dilation was not affected by PM exposure, indicating that the dilatory response was not
acting via endothelium-independent NO-mediated mechanisms. This finding is consistent with that
by Nurkiewicz et al. (2004, 087968) and suggests that the arteriolar smooth muscle is not involved in
the PM-impaired dilatation response.
      Vasoreactivity of aortic rings was measured in SH rats following exposure to 10 mg/kg PMi0
(EHC-93),  with an increase in ACh-induced vasorelaxation observed (Bagate et al., 2004, 087945).
This endothelium-dependent response was greatest at 4 h and was still present at 24 h. Similarly,
vasorelaxation induced by SNP 4-h post-PM exposure was enhanced. The vasorelaxation response
was attenuated after denudation of the aortic rings, suggesting that the effect was endothelium
dependent. The findings of enhanced dilation with PM exposure contrast with those reported by
Nurkiewicz et al. (2004, 087968; 2006, 088611). Tamagawa et al. (2008, 191988). and Cozzi et al.
(2006, 091380) and may be attributable to differences in PM type, animal species, or disease models.
The authors attribute their findings to the SH rat as a well-documented model of sympathetic
hyperactivity (increased affinity of aortic smooth muscle a-adrenergic receptors) that demonstrates
upregulation of NO formation and/or release (Safar et al., 2001, 156068). No change in
vasoconstriction was observed with PM with PHE or potassium chloride.
      Consistent with the impaired vasodilatory responses observed in the microvasculature and
aortic rings following PM exposure, Courtois et al. (2008, 156369) demonstrated less relaxation to
ACh in intrapulmonary arteries of Wistar rats exposed to a high dose (5 mg) of ambient PM
(SRM1648). This response was only observed 12 h after PM exposure and not at shorter (6 h) or
longer (24 or 72 h) time points. Fine TiO2 did not alter ACh-induced relaxation.

      Ultrafine PM

      Cozzi et al. (2006, 091380) used ICR mice to examine the effects of UF PM exposure (100 ug
collected from Chapel Hill, NC) on vascular reactivity following PM exposure and
ischemia/reperfusion injury. Aortic rings were evaluated for their contractile and dilatory responses
24 h post-exposure and following the ischemia/reperfusion protocol. Maximum ACh-induced
relaxation was impaired in UF PM-exposed vessels, as well as a rightward shift in sensitivity to
ACh. There was  no difference in constriction to PHE between aortic rings from control and
PM-exposed mice. The reduced ACh-induced relaxation may be important for reperfusion of critical
vascular beds following occlusion, potentially leading to a greater area of infarction (as in this
study). A new study in dogs supports the results observed in the above study and provides evidence
of reduced  myocardial blood flow following PM exposure (Bartoli et al., 2009, 179904). and is
discussed in more detail in Section 6.2.3.3.
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      Summary of Toxicological Study Findings for Vasoreactivity

      The toxicological findings with respect to vascular reactivity are generally in agreement and
demonstrate impaired dilation following PM exposure that is likely endothelium dependent. These
effects have been demonstrated in varying vessels (right spinotrapezius muscle, carotid arteries, and
aortic rings) and in response to different PM types (ROFA, TiO2, EHC-93, UF ambient PM). The
work by Nurkiewicz et al. (2004, 087968; 2006, 088611; 2008, 156816; 2009,  191961) supports a
role for increased ROS and RNS production in the microvascular wall that leads to altered NO
bioavailability and dysfunction following particle exposure.  Only one study showed enhanced
dilation with PM exposure, but the authors attributed the conflicting results to the SH rat. No
constriction changes in response to PHE were observed following PM exposure. The responses
observed in the pulmonary circulation after PM exposure include pulmonary vasoconstriction,
decreased L/W ratio, and impaired vasodilation in intrapulmonary arteries. These results are
consistent and indicate altered vascular tone. Enhancement of vasoconstriction  in mesenteric veins
following DE is the first study of its kind to report on venous circulatory effects.


      Endothelin

      In addition to studies that look at vascular reactivity, three recent studies  have examined
plasma ET levels following exposure to vehicle emissions and a few studies examined the mRNA
expression of ET-1 and ET receptors in the hearts of rodents following PM exposure.

      CAPs

      The upregulation of mRNA expressions of ET-1 and the ETA receptor in  WKY rats exposed to
CAPs (1 or 4 days; 4.5 h/day; mean mass concentration range 1,000-1,900 ug/m3; Yokohoma City,
Japan) was correlated with increasing PM cumulative mass collected on chamber filters (Ito et al.,
2008, 096823). Furthermore, relative cardiac mRNA expressions of ET-1  and ETA receptor were
significantly correlated with CYP1B1 and HO-1 expression, indicating a possible relationship
between ET-1 metabolism and oxidative stress.
      Another plasma mediator of vasomotor tone is asymmetric dimethylarginine (ADMA), which
is an endogenous inhibitor of NOS that is associated with impaired vascular function and increased
cardiovascular events. Dvonch et al.  (2004, 055741) assessed levels of ADMA  in Brown Norway
rats 24 h following a 3-day PM2.5 CAPs exposure in southwest Detroit (8 h/day; July 2002). CAPs
(mean mass concentration 354 ug/m3) resulted in increased plasma ADMA compared to air controls,
although the levels reported were well below the 2 uM range associated with increased CVD risk  in
humans in chronic studies. Therefore, the preliminary results identified anew potential biomarker of
vascular tone that had not previously been used in air pollution toxicological studies.

      Traffic-Related Particles

      A study of old rats (21  mo; F344) exposed to on-road highway aerosols (number concentration
range 0.95-3.13><105 particles/cm3; Interstate 90 between Rochester and Buffalo, NY) for 6 h
demonstrated decreased plasma ET-2 (18 h post-exposure) and unchanged levels of ET-1  and ET-3
(Elder et al., 2004, 0873541

      Gasoline Exhaust

      In contrast to the study above,  circulating levels of ET-1 (measured 18 h  post-exposure) were
elevated in animals exposed to gasoline exhaust and filtration of particles did not reduce this effect
(study details in Section 6.2.2.2) (Campen et al., 2006,  096879). The results of Campen et al. (2006,
096879) are consistent with those observed by  Bouthillier et al. (1998, 087110) following a very
high exposure to EHC-93, but it is difficult to attribute the effects to PM alone, as Campen et al.
(2006, 096879) showed that the gaseous components of the gasoline mixture were required for the
ET-1 increase.
      Aorta ET-1 mRNA expression was increased with a 7-day gasoline  exhaust exposure (60
ug/m3) in ApoE"" mice, but was not changed following a single-day exposure (Lund et al.,  2009,
180257).  The expression and activity of MMP-2 and -9  and oxidative stress in aortas of exposed
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mice were also elevated. The ET-1 and MMP-9 mRNA expressions were attenuated with the addition
of an ETA receptor antagonist (but not a radical scavenger), indicating that ET-1 may mediate the
expression of MMP-9 through the ETA receptor.

      Model Particles

      Another study examined the effects of UF carbon particles (mass concentration 172 ug/m3;
mean number concentration 9.0xl06 particles/cm3) and there was no difference in ET-1, ETA or ETB
receptor mRNA expression between air- and particle-exposed SH rats 1 or 3 days post-exposure
(Upadhyay et al, 2008, 159345). In lung homogenates, ET-1, ETA and ETB receptor mRNA
expressions were elevated 3 days after exposure to UF carbon particles (Upadhyay et al., 2008,
159345).


      Summary of lexicological Study Findings for Endothelin

      The ET responses were mixed, with one study demonstrating ET-1 increases after exposure to
gasoline emissions that were particle  independent and another reported decreased ET-2, but no
change in ET-1 or ET-3 with on-road  highway exposure. Elevated levels of ET-1  and ETA receptor
mRNA expression were noted in hearts of rats exposed to CAPs, but not in rats exposed to  UF
carbon particles. However, ET-1, ETA and ETB receptor mRNA expressions were increased in lung
homogenates  of rats following UF carbon exposure. The ETA receptor was  found to be involved in
the ET-1 and MMP-9 responses in the aortas of mice exposed to gasoline exhaust. A relatively novel
marker, ADMA, was used to evaluate vasomotor tone in rats and was found to be elevated following
exposure to CAPs, although the results are preliminary  and have not been confirmed.


6.2.5.   Blood Pressure

      One of the potential outcomes of air pollution-mediated alterations in vascular tone is its
impact on variable BP or hypertension. BP is tightly regulated by autonomic (central and local),
cardiac, renal, and regional vascular homeostatic mechanisms with changes in arterial tone being
countered by changes in cardiac  contractility, HR, or fluid volume. The evidence of PM-induced
changes in BP presented in the 2004 PM AQCD (U.S. EPA, 2004, 056905) is limited and
inconsistent. Recent epidemiologic, controlled human exposure, and toxicological studies have
similarly reported conflicting results regarding the effect  of PM on BP. However, the majority of
these studies have evaluated changes  in BP at some point following exposure to PM. Significant
increases in DBP have been observed in  controlled human exposure studies that evaluated BP during
exposure (concomitant exposure to CAPs and O3). In addition, evidence from toxicological studies
suggests that the effect of PM on BP may be modified by health status, as PM-induced increases in
BP have been more consistently  observed in SH rats.


6.2.5.1.   Epidemiologic Studies

      Increased BP was associated with PM concentration in two of three studies reviewed in the
2004 PM AQCD (U.S. EPA, 2004, 056905). Increases in  left ventricular BP (systolic and diastolic)
are well established risk factors for cardiovascular mortality/morbidity (Welin et al., 1993, 156151).
Changes in HR and BP both reflect changes in autonomic tone, and have been examined following
short-term increases in PM pollution  in several recent studies.
      Ibald-Mulli et al. (2004, 087415) examined associations between BP and ambient PM2.5
concentrations, UFP counts, and  ACP counts in a multicity panel study (Amsterdam, the
Netherlands; Helsinki, Finland; Erfurt, Germany) of 131 adults with coronary heart disease.
Although based on the same ULTRA Study (Timonen et  al., 2006, 088747) with study methods  as
described previously in Section 6.2.1.1, the study period was different. They investigated changes in
BP (SBP and DBP) associated with mean PM2.5, UFP, and ACP concentration/counts (lag days 0, 1,
and 2, as well as the 5-day mean) in each city and then generated a pooled estimate across the cities.
The median PM2.5 concentration  for each city is  provided in Table 6-5. Pooled analyses across all 3
cities showed small, but statistically significant decreases in SBP and DBP  associated with various
single day lagged concentrations/counts of each particulate pollutant. Each 10 (ig/m3 increase in the
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mean PM25 concentration over the previous 5 days was associated with a 0.36 mmHg decrease in
SBP (95% CI: -0.99 to 0.27) and a 0.39 mmHg decrease in DBF (95% CI: -0.75 to -0.03). Each
10,000 particles/cm3 increase in UFP was associated with a 0.72 mmHg decrease in SBP (95%
CI: -1.92 to 0.49), and a 0.70 mmHg decrease in DBF (95% CI: -1.38 to -0.02). Each
1,000 particles/cm3 increase in 5-day avg ACP was associated with a 1.11 mmHg decrease in SBP
(95% CI: -2.12 to -0.09) and a 0.95 mmHg decrease in DBP (95% CI: -1.53 to -0.37). The authors
concluded that these findings do not support previous findings of an increase in BP associated with
increases in particulate pollutant concentrations.
     Single-city studies examining the association between BP and particulate air pollution have
been done in several U.S.  and Canadian cities. Dales et al. (2007, 155743) conducted a panel study
of 39 healthy volunteers who sat outside at two different bus stops for 2-h in Ottawa, Canada. The
median PM2.5 concentrations measured at the bus stops during each 2-h exposure session were 40
and 10 (ig/m . Post-exposure SBP and DBP were not associated with the mean PM2.5 concentration
measured at the bus stops during the 2-h exposure session. The change in BP from pre- to
post-exposure was not evaluated, as health measurements were only made after the 2-h exposure
sessions.
     Jansen et  al. (2005,  082236) studied changes in BP among 16 older subjects (aged 60-86 yr)
with asthma or COPD in Seattle, Washington, associated with indoor, outdoor, and personal PMi0,
PM2.5, and BC concentrations on 12 consecutive days. The study authors reported that no
associations were observed between BP and daily mean PMi0, PM2.5, or BC concentrations.
     Zanobetti et al. (2004, 087489) examined the association between BP (SBP, DBP, and mean
arterial BP) and mean PM25 concentrations in the previous 24, 48, 72, 96, and 120 h in 62 elderly,
cardiac rehabilitation patients in Boston, MA (Zanobetti et al., 2004, 087489). Each 10.4  (ig/m3
increase in mean PM25 concentration in the previous 120 h was associated with significant increases
in resting DBP (2.82 mmHg [95%  CI: 1.26-4.41]), SBP (2.68  mmHg [95% CI: 0.04-5.38]), and
mean arterial BP (2.76 mmHg [95% CI:  1.07-4.48]).
     Mar et al. (2005, 087566) studied this same PM25-BP association in 88 subjects aged >57 yr in
Seattle, WA. Among healthy subjects taking medications (bronchodilators, inhaled corticosteroids,
anti-hypertensives, |3-blockers, calcium channel blockers, and/or cardiac glycosides), each 10 (ig/m3
increase in mean outdoor PM2 5 concentration on the same day as the BP measurement was made
was associated with small increases in SBP and DBP. However, among all subjects,  each 10 (ig/m3
increase in same day mean PM2 5 concentration was associated with non-significant  decreases in SBP
(-0.81 mmHg [95% CI: -2.34 to 0.73]) and DBP (-0.46 mmHg [95% CI: -1.49 to 0.57]).
     As described earlier, Ebelt et al. (2005, 056907) conducted a repeated measures panel study of
16 patients with COPD in the summer of 1998 in Vancouver, British Columbia to  evaluate the
relative impact of ambient and non-ambient exposures to PM25, PMi0, and PMi0_2.5 on multiple
health outcomes including ectopy and BP. Using the  same analytic methods, pollutant
concentrations, and lags, they reported decreased SBP associated with same day ambient exposures
to each PM size fraction.
     Two similar studies were done in Incheon,  South Korea (Choi et al., 2007, 093196) and
Taipei, Taiwan (Chuang et al., 2005, 156356). Choi et al. (2007, 093196) reported significantly
increased SBP and DBP associated with the mean PMi0 concentration over the same and previous 2
days in the warm season only (July to September). Chuang et  al. (2005, 156356) reported significant
increases in SBP and DBP associated with the mean UFP count (0.01-0.1 (im particles) 1-3 h before
the BP measurement.


     Summary of Epidemiologic Studies of Blood Pressure

     These studies (Choi et al., 2007, 093196; Chuang  et al., 2005, 156356; Dales et al., 2007,
155743; Ibald-Mulli et al., 2004, 087415; Mar et al., 2005, 087566; Zanobetti et al., 2004, 087489)
are not entirely consistent with regard to their BP-PM associations. Most have reported increases in
SBP and DBP associated with increases in either PM25, PMi0, or UFP (Choi et al., 2007,  093196;
Chuang et al., 2005,156356; Mar et al.. 2005. 087566; Zanobetti  et al.. 2004. 087489). However.
two studies reported small decreases  in BP associated with multiple particulate pollutants  (Ibald-
Mulli et al., 2004, 087415; Mar et al., 2005, 087566). Dales et al. (2007, 155743) reported no
change in BP associated with a 2-h exposure to bus stop PM2 5 and Jansen at al. (2005, 082236)
reported null findings among older adults in Seattle, WA. Exposure lags ranging from 1-3 h (Chuang
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et al, 2005, 156356). to the same day(Ebelt et al., 2005, 056907; Mar  et al., 2005, 087566). to the
mean across the previous 5 days (Zanobetti  et al., 2004, 087489) were  reported as having the
strongest associations with BP.  Mean and upper percentile concentrations for PM from these studies
are presented in Table 6-5.

Table 6-5.     Mean PM concentrations reported in epidemiologic studies of blood pressure.
          Author
         Location
 Mean Concentration (ug/m
      Upper Percentile
   Concentrations (ug/m3
PM2.5
Dales (2007,155743)
Ottawa, Canada (bus stops)
Bus stop 1:40
Bus stop 2:10
                                                                               NR
Ebelt (2005.056907)
Ebelt (2005,056907)
Vancouver, Canada
Ambient (measured): 11.4
Personal (estimated): 7.9
Personal (measured): 18.5
Ambient (measured) range:
4.2-28.7
Personal (estimated) range:
0.9-21.3
Personal (measured) range:
2.2-90.9
Amsterdam, Netherlands
Ibald-Mulli (2004, 087415) Erfurt, Germany
Helsinki, Finland
Jansen (2005, 082236) Seattle, WA
Mar (2005, 087566) Seattle, WA
Zanobetti (2004, 087489) Boston, MA
20
23.1
12.7
10.47
Healthy: Personal- 9.3
Indoor- 7.4
Outdoor- 9
CVD: Personal- 10.8 Indoor- 9.5
Outdoor- 12.6
COPD: Personal- 10.5
Indoor- 8.5
Outdoor- 9.2
Median: 8.8
50th: 16. 9
75th: 23.9
Max: 82.2
50th: 16. 3
75th: 27.4
Max: 118.1
50th: 10. 6
75th: 16
Max: 39.8
NR
NR
90th: 17. 6
PMiO-2.5
Vancouver, Canada
Ambient (calculated): 5.6
Personal (estimated): 2.4
Ambient (calculated) range: -1.2 to
11.9
Personal (estimated) range: -0.4 to
7.2
PMu
Choi (2007, 093196)
Incheon, South Korea
July-Sept: 42.1
Oct.-Dec: 53.5
July-Sept.: 75%: 52.2
Max: 136.7
Oct.-Dec.: 75%: 64.5
Max: 209.6
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Author Location
Chuang (2005, 156356) Taipei, Taiwan
Ebelt (2005, 056907) Vancouver, Canada
Jansen (2005. 082236) Seattle, WA
Mar (2005. 087566) Seattle, Washington
Mean Concentration (ug/m3)
54.1
Ambient (calculated): 17
Personal (estimated): 10.3
13.47
Healthy: 14.5
CVD:18
COPD:14.3
Upper Percentile
Concentrations (ug/m3)
Range: 10.3-1 39.8
Ambient (calculated) range: 7-36
Personal (estimated) range:
1.5-23.8
NR
NR
      Right Ventricular Pressure

      Several recent studies, summarized in the section on hospital admissions and emergency
department (ED) visits for CVD causes, have reported increased risk of hospital admissions for CHF
associated with increased PM concentration on the same day (Wellenius  et al., 2005, 087483; 2006,
088748). As a possible mechanism for these reported associations, Rich et al. (2008, 156910)
hypothesized that these hospital admissions for decompensation of heart failure would be preceded
by more subtle increases in pulmonary arterial (PA) and right ventricular (RV) diastolic pressures.
They used passively monitored PA and RV pressures on 5,807 person-days, among 11 subjects
implanted with the Chronicle Implantable Hemodynamic Monitor [Medtronic, Inc. Medtronic,
MN]). Using a two-stage modeling process, they examined the change in daily mean right heart
pressures associated with mean PM2.5 concentration on the same and previous 6 days. Each
11.62 ug/m3 increase in same day mean PM2.5 concentration was associated with small, but
statistically significant increases in estimated PA diastolic pressure (0.19 mmHg [95% CI: 0.05-
0.33]) and RV diastolic pressure (0.23 mmHg [95% CI: 0.11-0.34]). These effects were not
attenuated when controlling for all lags simultaneously. Thus, PM induced right heart pressure
increases may mark another potential pathway between PM exposure and incidence of
cardiovascular events, but further studies on this same hypothesis are needed for confirmation.
      Wellenius et al. (2007, 092830) conducted a panel study of 28 subjects living in the greater
Boston metropolitan area, each with chronic  stable heart failure and impaired systolic function. They
hypothesized that circulating levels of B-type natriuretic peptide (BNP), measured in whole blood  at
0, 6, and 12 wk, were associated with acute changes in ambient air pollution, as a possible
mechanistic explanation for the observed association between hospital admissions for CHF and
ambient PM concentration (Wellenius et al.,  2005, 087483; 2006, 088748). During the study the
mean PM2.5 concentration was 10.9 ug/m3, while the mean BC concentration was  0.73 ug/m .  Using
linear mixed models, they reported no association between any pollutant (PM2.5, CO, SO2, NO2, O3,
and BC) and BNP at any lag (e.g., each 10 ug/m3 increase in mean daily  PM25 concentration [0.8%
increase in BNP (95% CI: -16.4 to 21.5)]) (Wellenius  et al.,  2007, 092830).  However, BNP the
active peptide has a very short half-life and might not be the best biomarker  for such a study. Thus
the absence of a correlation between PM and BNP may not suggest that PM  does not have an impact
on RV or LV function in individuals with impaired cardiac mechanics.


6.2.5.2.   Controlled Human Exposure Studies

      Only one controlled human exposure study cited in the 2004 PM AQCD (U.S. EPA, 2004,
056905) reported any PM-induced changes in BP. Gong et al. (2003, 042106) found that exposure  to
PM2.5 (174 ug/m3) decreased SBP in asthmatics, but increased SBP in healthy subjects. Among
healthy adults, BP was not affected following 2-h exposures  to 200 ug/m3 diesel PM (Nightingale  et
al., 2000 011659). 150 ug/m3 PM25 CAPs with 120 ppb O3 (Brook et al., 2002, 024987). or
10 ug/m  UF carbon particles (Frampton, 2001, 019051). The effect of PM on BP has been further
investigated in several recent controlled human exposure studies, which are described below.
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      CAPS

      One recent study demonstrated a significant increase (9.3%) in DBF among healthy adults
immediately prior to the end of a 2-h exposure to  150 ug/m3 PM25 CAPs in combination with
120 ppb O3 (Urch et al., 2005, 081080). The authors also found that the magnitude of change in BP
was significantly associated with PM2.5 carbon content, but not total PM2.5 mass. It was postulated
that the disparity between these findings and those of a similar study by the same group (Brook et
al., 2002, 024987) could be due to differences in experimental methods. The Brook et al. (2002,
024987) study measured post-exposure BP approximately 10 min following exposure, while the
study by Urch et al. (2005, 081080) measured BP during exposure. In a follow up study that
evaluated changes in BP during a 2-h exposure to PM2 5 CAPs, Fakhri et al. (2009, 191914) reported
a significant increase in DBP with exposure to CAPs with, but not without, coexposure to O3.


      Diesel Exhaust

      Several recent studies have assessed BP  changes  following a 1-h exposure to DE with a
particle concentration of 300 ug/m3. Mills et al. (2005,  095757) evaluated changes in BP 2 h
following exposure to DE and found a 6 mmHg increase in DBP of marginal statistical significance
(p = 0.08) compared to filtered air control. In this  same group of subjects, Tornqvist et al. (2007,
091279) did not observe any such changes in BP 24 h following DE exposure. At lower particle
concentrations in diluted DE (100-200 ug/m3 PM2.5), Peretz et al. (2008, 156854) did not observe
any changes in systolic or DBP in either healthy adults  or adults with metabolic syndrome
immediately following a 2-h exposure. Further, although Lundback et al. (2009, 191967) reported an
increase in arterial stiffness following exposure to DE with a particle concentration of 330 ug/m3
among healthy young adults, no changes in systolic or diastolic BP were observed during or
following exposure relative to filtered air.


      Model Particles

      Routledge et al. (2006, 088674) did not observe any changes in BP among healthy older adults
and older adults with stable angina following a 1-h exposure to UF EC  (50 ug/m3), with or without
coexposure to 200 ppb SO2. Similarly, neither Shah et al. (2008, 156970). nor Beckett et al. (2005,
156261) reported any changes in BP among healthy adults following exposure to UF EC (50 ug/m3)
or ZnO (500 ug/m3 fine and ultrafine), respectively.


      Summary of Controlled Human Exposure Study Findings for BP

      The findings of these new studies do not provide convincing evidence of an association
between PM exposure and an increase in BP; however, they do suggest that there is a need for
additional investigations of PM-induced changes in BP at various time points following exposure.


6.2.5.3.  lexicological Studies

      In healthy animal models, little evidence exists for significant BP changes following inhalation
exposure to environmentally-relevant concentrations of PM. Only one animal toxicological study is
mentioned in the 2004 PM AQCD (U.S. EPA, 2004, 056905) that examined BP with PM exposure
and no effect was observed (Vincent et al., 2001,  021184).


      CAPs

      In a recent study of dogs, exposure to PM2 5 CAPs from Boston (mean mass concentration
358.1 ug/m3; mass concentration 94.1-1557 ug/m3) for  5 h resulted in increased SBP (2.7 mmHg),
DBP (4.1 mmHg), mean arterial pressure (3.7 mmHg),  and lowered pulse pressure (1.7 mmHg)
when measured upstream of the femoral artery (Bartoli et al., 2009, 156256). Administration of an
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a-adrenergic antagonist (prazosin) prior to CAPs attenuated the BP responses. These findings
indicate that CAPs exposure may have activated a-adrenergic receptors and increased peripheral
vascular resistance. Baroreflex sensitivity was measured immediately before and after exposure
during a transient elevation of arterial pressure that was induced by PHE; increased baroreflex
sensitivity was observed in subgroup of dogs exposed to CAPs, which is consistent with an
upregulation of vagal reflexes.
      Chang et al. (2004, 055637) noted slight increases in SH rat BP (5-10 mmHg) when exposed
to PM2.5 CAPs (mean mass concentration 202 ug/m3) during spring months. However, during
summer months, when the CAPs exposure level was less (140 ug/m3), this effect was not observed.
It was unclear, therefore, whether the effects were seasonal or dose-related. In a preliminary study of
SH rats exposed to CAPs during a dust storm event, mean BP was elevated the third and fourth hour
of a 6-h exposure, although interpretation of this finding is difficult due to few animals in the
exposure group (n = 2) (Chang et al., 2007, 155719). In another study, the increased change in mean
BP measured using the tail cuff method following CAPs exposure weakly correlated with PM mass
accumulated on chamber filters over the entire exposure duration (Section 6.2.4.3 for details) (Ito  et
al., 2008, 096823). Furthermore, ETA receptor mRNA expression in cardiac tissue was positively
correlated with the change in mean BP.


      Model Particles

      In WKY rats, 24-h exposure to UF carbon particles (mass concentration 180 ug/m3; mean
number concentration 1.6x107 particles/cm3) did not alter mean BP during exposure or the recovery
periods (Harder et al., 2005,  087371). SH rats exposed to UF carbon particles for 24 h (mass
concentration 172 ug/m3; mean number concentration (9.0xl06 particles/cm3) resulted in elevated
mean BP (by 6 mmHg) on the first and second days of recovery following exposure that was
attributable to increases in both SBP and DBP (Upadhyay et al., 2008, 159345). Increased plasma
renin concentrations were observed in CB-exposed rats on the first and second days of recovery,
although renin activity and angiotensin (Ang) I and II concentrations were not affected by particle
exposure.


      Summary of lexicological Study Findings for Blood Pressure

      Limited toxicological evidence provides support for elevated BP in dogs or compromised rats
with CAPs, UF CAPs, CAPs  during a dust storm event, or UF carbon particle exposure. However,
most of the CAPs studies were conducted outside of the U.S.
6.2.6.  Cardiac Contractility

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) did not include any toxicological studies that
evaluated cardiac contractility either directly or indirectly following exposure to PM. Two recent
animal toxicological studies have demonstrated reductions in cardiac fractional shortening,
diminished ejection shortening, or changes in the QA interval following PM exposure. The results of
these studies provide some evidence of PM-induced changes in cardiac contractility in animal
models.


6.2.6.1.   Toxicological Studies

      The strength of the contracting heart is reflected by its contractility. In heart failure,
contractility wanes significantly and the heart cannot compensate during periods of increased
physical activity. Measuring true contractility in a whole animal is difficult, requiring extensive
surgical instrumentation and monitoring.
December 2009                                 6-38

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      CAPS

      Using radiotelemetry to indirectly measure cardiac contractility through the QA interval, SH
rats were repeatedly and alternately exposed to UF CAPs in Taiwan on separate days in spring or
summer (details provided in Section 6.2.5.3) (Chang et al., 2004, 055637). The QA interval was
calculated as the time duration between the Q wave in the ECG and point A (upstroke in aortic
pressure) in the pressure trace and is not as reliable as other measures, such as echocardiography.
During the spring exposure, QA interval decreased by 1.6 ms (as demonstrated by fixed effects in
linear mixed-effects modeling), which indicates an increase in cardiac contractility. There were no
changes in QA interval observed for the summer months, which may be attributable to lower UF PM
concentrations (mean mass concentration 140 ug/m3) or differing PM compositions.


      Model  Particles

      A recent study using old (18-28-mo) mice (C57BL/6, C3H/HeJ, and B6C3F1) demonstrated
significant reductions in cardiac fractional shortening (due to increased left ventricular end-diastolic
and end-systolic diameters) following a 4-day (3 h/day) exposure to CB (PM2.5 mean concentration
401 ug/m ; PMi0 mean concentration 553 ug/m3) using echocardiography (Tankersley et al., 2008,
157043). Hemodynamic measurements of diminished ejection fraction and maximum change in
pressure over time further supported lowered myocardial contractility. Furthermore, increased right
ventricular pressure associated with elevated right atrial and pulmonary vascular pressures and
resistance, was indicative of pulmonary vasoconstriction in CB-exposed mice. Heart tissue and
isolated cardiomyocytes from exposed animals demonstrated enhanced ROS that was partially
attributable to NO S3-uncoupling and elevated MMP-2 and MMP-9 levels, which may implicate
myocardial remodeling. The combined results from this study suggest that cellular mechanisms
involving NOS-uncoupled ROS generation likely mediate PM-induced cardiac effects. Furthermore,
mRNA expression for atrial and brain natriuretic peptides was increased in hearts from exposed mice
compared to control, which is consistent with pulmonary congestion. There were no reported
strain-related  differences in any response.


      Intratracheal Instillation

      Similar to the responses observed by Tankersley et al. (2008, 157043). decreases in fractional
shortening and increases in left  ventricular end  diastolic diameter measured by echocardiography
were also reported for SD rats at 24 h post-IT exposure to DE particles (250 ug)  (Yan et al., 2008,
098625). A subset of rats received isoproterenol to induce myocardial injury prior to IT instillation of
DE particles and these animals demonstrated lowered fractional shortening at baseline, which was
decreased to an even greater extent with DE particle exposure; left  ventricular end diastolic diameter
was not affected by DE particles in these rats.


      Summary of lexicological Study Findings for Cardiac Contractility

      The studies above provide some evidence that cardiac contractility may be altered
immediately following PM exposure in animal  models. Results from the Tanksersley (2008, 157043)
and Yan (2008, 098625) studies provide the strongest support for PM-induced contractility changes
with inhalation exposure, as echocardiography  and hemodynamic measurements are well-established
for examining cardiac function.
6.2.7.  Systemic Inflammation
      The evidence presented in the 2004 PM AQCD (U.S. EPA, 2004, 056905) of increases in
markers of systemic inflammation associated with PM was limited and not sufficient to formulate a
definitive conclusion. Recent controlled human exposure and toxicological studies continue to
provide mixed results for an effect of PM on markers of systemic inflammation including cytokine
December 2009                                  6-39

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levels, C-reactive protein (CRP), and white blood cell (WBC) count. While results from recent
epidemiologic studies have also been inconsistent across studies, there is some evidence to suggest
that PM levels may have a greater effect on inflammatory markers among populations with
preexisting diseases.


6.2.7.1.   Epidemiologic Studies

      Several studies reviewed in the 2004 PM AQCD (U.S. EPA, 2004, 056905) investigated the
association of short-term fluctuations in PM concentration with markers of inflammation. These
studies were found to offer limited support for mechanistic explanations of the associations between
PM concentration and heart disease outcomes. Recent studies, published since 2002, are reviewed
below. CRP was measured in multiple studies, allowing the consistency of findings across
epidemiologic studies to be evaluated. Several other markers were examined in only a few studies, in
relation to a wide range PM size fractions and components. These markers included IL-6, TNF-a,
vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), soluble
CD40 ligand (sCD40L), WBCs, and soluble adhesion molecules  (sP-selectin and e-selectin).
      Diez-Roux et al. (2006, 156400) examined whether CRP increased in  response to changes in
the mean ambient PM2.5 concentrations in the prior day, prior 2 days, prior week, prior 30 days, and
prior 60 days among participants in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort.
Subjects (n = 5,634) lived in either Baltimore City or County, MD, Chicago, IL, Forsyth County,
NC, Los Angeles County, CA, Northern Manhattan and the Bronx, NY, or St. Paul, MN. The authors
report finding no evidence of a short-term  effect of PM2.5 on CRP in their population-based sample.
Of the five exposure measures examined, only the 30-day and 60-day mean  exposures showed
positive associations with PM2.5 (3% [95% CI: -2 to 10] and 4% [95% CI: -3 to 11] per 10 (ig/m3,
respectively).
      Ruckerl et al. (2007, 156931) conducted a multicity  longitudinal study to examine whether
changes in markers of inflammation were associated with short-term increases in particulate
concentrations (PMi0, PM2.5, PNC) and gaseous pollutant (NO2, SO2,  CO, O3). Study subjects were
MI survivors (n= 1,003) living in either Athens, Greece; Augsburg, Germany; Barcelona,  Spain;
Helsinki, Finland; Rome, Italy; or Stockholm, Sweden. Repeated measurements of IL-6 and CRP
were made during the study. Fibrinogen was also measured in this study and results are discussed in
Section 6.2.8.1.  The mean city-specific pollutant concentrations during the study are shown below in
Table 6-6. In pooled analyses, each interquartile range (not provided)  increase in PNC in the  12-17 h
before the health measurement was  associated with  a 2.7% increase in the geometric mean IL-6
levels (95% CI:  1.0-4.6). None of the pollutants, at any lag, were associated  with CRP levels in these
subjects. There did not appear to be effect modification of these results by smoking, diabetes, or
heart failure. Ljungman et al. (2009, 191983) studied the modification of the IL-6 association with
several PM size fractions (PMi0, PM2 5, PNC) by three IL-6 SNPs, one fibrinogen a  chain (FGA)
single-nucleotide polymorphism (SNP) and one fibrinogen (3 chain (FGB) SNP The associations of
PM25 and PMi0 with plasma level of IL-6 were stronger among those with the homozygous minor
allele genotype of FGB rs!800790 and among those homozygous for  the major allele genotype of
IL-6 rs2069832. Gene-environment interactions were most pronounced for CO. Modification the
PNC-IL-6 association by genotype was not apparent in these data, nor was modification of the PM-
IL-6 associations by FBA.
      Single-city studies of systemic inflammation have also been conducted in the U.S. and
Canada. Delfmo et al. (2008, 156390) measured CRP, IL-6, TNF-a, sP-selectin, sVCAM-1 and
sIC AM-1 in blood during a period of 12 wk. Associations of these markers with average PM
concentration (PM0.25, PM0.25_2.5, PM10_2.?, PNC, EC, OC, BC, primary OC, secondary OC) 24 h to 9
days prior to the blood draw were examined.  Subjects included residents of two downtown Los
Angeles nursing homes who were >65 yr old with a history of coronary artery disease. Both 24-
h avg and multiday average concentrations of PM0.25, EC, primary OC, BC,  PNC and gaseous
pollutants were associated with CRP, IL-6  and sP-selectin.
      Pope et al. (2004, 055238) conducted a panel study of 88 non-smoking, elderly subjects
residing in the Salt Lake City, Ogden, and  Provo metropolitan area of Utah.  Each 100 (ig/m3  increase
in same day mean PM25 concentration was associated with a 0.81 mg/dL increase in CRP (95%
CI: 0.48-1.14), but not WBCs. However, when excluding 1 influential subject, each  100 ug/m3
increase in same day mean PM25 concentration was associated with only a 0.19 mg/dL increase in
December 2009                                 6-40

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CRP (95% CI: -0.01 to 0.39). Several markers of coagulation were examined in this study and are
discussed in Section 6.2.8.1.
      Zeka et al. (2006, 157177) studied 710 elderly members of the VA Normative Aging Study to
examine changes in CRP, sediment rate and WBCs with acute changes in PM concentrations in the
previous 48 h, 1 wk, and 4 wk. Results for fibrinogen are discussed in Section 6.2.8.1. They did not
find consistent or significant associations with any pollutant and CRP or WBC  count. Sediment rate
was significantly increased with PNC, BC and PM2 5 concentration averaged over the previous 4 wk
period. Modification of these PM effects by obesity, GSTM1 genotype and statin use was suggested
in this study.
      O'Neill et al. (2007, 091362) conducted a cross-sectional study of 92 Boston residents with
type 2 diabetes, to examine the association between plasma levels of 1C AM-1,  VCAM-1 and PM
concentrations. Results for markers of coagulation measured in this study are discussed in
Section 6.2.8.1. PM2.5, BC, and SO42" concentrations were measured 0.5 km from the patient exam
site. For all moving averages examined (1-6 days), increases in mean PM25 and BC concentration
were associated with increased ICAM-1 and VCAM-1 concentrations. Each 7.6 (ig/m3 increase in
the mean PM25 concentration over the previous 6  days was associated with a 11.76 ng/mL increase
in VCAM-1  (95% CI:  3.48-20.70), and each 0.6 (ig/m3 increase in the mean BC concentration over
the previous 6 days was associated with a 27.51 ng/mL increase in VCAM-1 (95% CI:  11.96-45.21).
There were no consistent associations between mean SO42" concentration and any marker at any lag.
      Sullivan et al. (2007, 100083) conducted a panel study of 47 subjects (aged >55 yr) either with
COPD (n = 23) or without COPD (n = 24) in Seattle, WA. They examined the association between
levels of CRP and mean daily PM2 5 concentration. Most values for IL-6 and TNF-a were below the
limit of detection, so these cytokines were not included in the analyses. Results for fibrinogen and
D-dimer are discussed in Section 6.2.8.1. They did not find any associations between 24-h mean
PM2 5 concentrations and levels of CRP in individuals with or without COPD.
      In the study by Liu et al. (2006, 192002; 2007, 156705). conducted in Toronto, Ontario,
neither CRP (0.11 (ig/mL [95% CI: -0.03 to 0.25]) nor TNF-a (0.03 pg/mL [95% CI: -0.07 to 0.13])
was associated with personal exposure to PMi0 (24-h averaging time).
      Similarly, there was no association with IL-6. However, significant positive associations with
markers of oxidative stress, FMD and BP were found and are discussed in Sections 6.2.9.1, 6.2.4.1,
and 6.2.5.1, respectively.
      In the St. Louis Bus Study, each 5.4 (ig/m3 increase in the mean PM2 5 concentration over the
previous week was associated with 5.5% increase in WBCs (95% CI: 0.10-11)  (Dubowsky et al.,
2006, 088750). Each 6.1 (ig/m3 increase in the mean PM2 5 concentration over the previous 5 days
was associated with a 14% increase in CRP among all subjects (95% CI: -5.4 to 37), but an 81%
increase in CRP (95%  CI: 21-172) among subjects with diabetes, obesity, and/or hypertension.
Associations between PM2 5 and IL-6 were only observed among those with diabetes, obesity, and/or
or hypertension. In another study of in-vehicle PM2 5, each 10 (ig/m3  increase during a work-shift
was associated with decreased lymphocytes, increased mean corpuscular volume, neutrophils, and
CRP over the next 10-14 h among 9 healthy North Carolina state troopers (Riediker  et al., 2004,
056992). Associations  of roadside and ambient PM25 with systemic inflammatory markers were
weaker and non-significant in this population.
      International studies of the effect of air pollution on markers of inflammation have been
conducted with mixed  results. Two studies conducted among 57 male patients with coronary heart
disease in Erfurt, Germany, found associations of UFP, ACP and PMi0 with CRP (Ruckerl et al.,
2006, 088754) and UFP and ACP with sCD40L, a marker for platelet activation (Ruckerl  et al.,
2007, 156931). In a large cross-sectional study of healthy  subjects in Tel Aviv,  Steinvil et al. (2008,
188893) examined biological markers of inflammation (CRP and WBCs) collected as part of routine
health examinations for 3,659 individuals. Associations with air pollutants (including PM10)
measured at local monitoring sites for the day of the examination and up to 7 days prior were
examined. No significant associations were found between pollutant  levels and indications of
enhanced inflammation. By contrast, PMi0, PM25, SO42~ and nitrate (3-day avg concentrations) were
associated with increases in hs-CRP in healthy students in Taiwan (Chuang  et  al., 2007, 091063).
PMio, PM25 and PM0.2s were not associated with CRP in a study of MI patients in Italy, although
associations with autonomic dysregulation and more severe arrhythmias were observed (Folino et
al., 2009, 191902). Kelishadi et al. (2009, 191960) reports that CRP,  as well as  markers of insulin
resistance and oxidative stress (discussed in Section 6.2.9.1), were associated with PMi0 in a cross-
December 2009                                 6-41

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sectional study of a population-based sample of children 10-18 yr old in Iran (mean PM
concentration 122.08 (ig/m3).
                                                  10
      Summary of Epidemiologic Study Findings for Systemic Inflammation

      The most commonly measured marker of inflammation in the studies reviewed was CRP. CRP
was not consistently associated with short-term PM concentrations (PM2.5, PMi0, SO^, EC, OC,
PNC). A multicity study of MI survivors in Europe (Ruckerl et al., 2007, 156931) failed to provide
evidence  of an effect of PM (e.g., PMi0, PM2.5, PNC) on CRP and no effect was observed by Diez-
Roux et al. (2006, 156400) in a population-based study when concentrations were averaged over
periods less than 30 days. Several other markers of inflammation have been examined in relation to
several PM size fractions and components, but the number of studies examining the same
marker/PM metric combination is too few to allow results to be compared across epidemiologic
studies. Mean and upper percentile concentrations for those epidemiologic studies that evaluated
systemic  inflammation are included in Table 6-6.
Table 6-6.     PM concentrations reported in epidemiologic studies of inflammation, hemostasis,
            thrombosis, coagulation factors and oxidative stress.
        Author
Location
Mean Concentration (ug/m
Upper Percentile Concentrations
        (ug/m3)
PM2.5
Chuang (2007, 091063)
Diez-Roux (2006, 156400)
Dubowsky (2006, 088750)
Folino (2009, 191902)
O'Neill (2007, 091362)
Park (2008, 156845)
Peters (2009, 191992)
Taipei, Taiwan
Chicago, IL
Baltimore, MD
Forsyth County, NC
Los Angeles, CA
New York City, NY
St. Paul, MN
St. Louis (bus stops)
Padua, Italy
Boston, MA
Boston, MA
Helsinki, Finland
Stockholm, Sweden
Augsburg, Germany
Rome, Italy
Barcelona, Spain
1-dayavg:31.8
2-dayavg:36.4
3-dayavg:36.5
Prior day (median): 14.3
Prior 2 days (median): 14.4
Prior 7 days (median): 15.24
Prior 30 days (median): 15.69
Prior 60 days (median): 15.9
16
Summer: 33.9
Winter: 62.1
Spring: 30.8
11.4
12
Helsinki: 8.2
Stockholm: 8.8
Augsburg: 17.4
Rome: 24.5
Barcelona: 24.2
Total: 16.4
1-day avg (range): 16.2-50.1
2-day avg (range): 15-53.4
3-day avg (range): 12. 7-59. 5
Prior day (75th): 20.9
Prior 2 days (75th): 20.35
Prior 7 days (75th): 19.7
Prior 30 days (75th): 19.22
Prior 60 days (75th): 19.08
75th: 22
100th: 28
NR
Range: 0.07-33.7
Range: 2-62
Helsinki (range): 1-28
Stockholm (range): 0-27
Augsburg (range): 6-39
Rome (range): 4-95
Barcelona (range): 3-95
Total (range): 0-95
December 2009
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Author
Pope (2004, 055238)
Riediker (2004, 056992)
Ruckerl (2007, 156931)
Ssrensen (2003, 157000)
Sullivan (2007, 100083)
Zeka (2006. 157177)
Location
Salt Lake City, Ogden, Provo Utah
North Carolina State Troopers
Helsinki, Finland
Stockholm, Sweden
Augsburg, Germany
Rome, Italy
Barcelona, Spain
Athens, Greece
Copenhagen, Denmark
Seattle, WA
Boston, MA
Mean Concentration (ug/m3)
FRM-Filled:23.7
Not filled: 25.8
TEOM:18.9
RAMS/PC-BOSS: 26. 5
Light Scatter: 24.1
Mass: 23
Ambient: 32.3
Roadside: 32.1
8.2(19.4)
8.8(19.1)
17.4(29.3)
24.5(54.1)
24.2 (64.7)
23 (46)
Personal (median): 16.1
Urban background (median): 9.2
Outdoor (median): 7.7
Indoor (median): 7.7
48h (median): 9.39
Upper Percentile Concentrations
(ug/m3)
FRM-Filled (range): 1.7-74
Not filled (range): 1.7-74
TEOM (range): 2.2-61 .5
RAMS/PC-BOSS (range): 5.6-72.4
Light Scatter (range): 4.5-54.4
Mass (range): 7.1-38.7
Ambient (range): 9.9-68.9
Roadside (range): 8.9-62.2
NR
NR
NR
NR
NR
NR
Personal (025-075): 10-24.5
Urban background (025-075): 5.3-14.8
Outdoor: 75th- 11. 5
90th- 19.9
Max- 33.9
Indoor: 75th- 12.1
90th- 16
Max- 81 .4
75th: 14.57
90th: 21 .48
PMiO-2.5
Delfino (2008, 156390)
Peters (2009, 191992)
Los Angeles, CA
Helsinki, Finland
Stockholm, Sweden
Augsburg, Germany
Rome, Italy
Barcelona, Spain
Outdoor: 10.04 (4.07)
Indoor: 4.1 2 (4.76)
Helsinki: 8.9
Stockholm: 9
Augsburg: 15.8
Rome: 16.8
Barcelona: 16.5
Total: 13.3
Outdoor (range): 1.76-22.38
Indoor (range): 0.1 2-37.63
Helsinki (range): 1-38
Stockholm (range): 0-40
Augsburg (range) :-1 to 35
Rome (range): -33 to 65
Barcelona (range): 1-102
Total (range): -33 to 102
PM10
Baccarelli (2007. 090733)
Baccarelli (2007. 091310)
Chuang (2007, 091063)
Lombardia Region, Italy
Lombardia Region, Italy
Taipei, Taiwan
Sep-Nov(median):51.2
Dec-Feb (median): 68.5
Mar-May (median): 64.1
Jun-Aug (median): 44.3
Median: 34.1
1-dayavg:49.2
2-dayavg:55.3
3-day avg: 54.9
Sep-Nov (max): 148.9
Dec-Feb (max): 238.3
Mar-May (max): 158.5
Jun-Aug (max): 94.7
Maximum: 390
1 -day avg (range): 29. 5-83. 4
2-day avg (range): 25. 5-85.1
3-day avg (range): 22.2-87.2
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         Author
Location
Mean Concentration (ug/m
Upper Percentile Concentrations
         (ug/m3)

Folino (2009, 191902) Padua, Italy


Kelishadi (2009, 191960) Isfahan, Iran
Summer: 46.4
Winter: 73
Spring: 38.3

122.08

NR

75th: 153
100th: 191
                       Washington County, MD
                       Forsyth County, NC
                       Minneapolis, MN (suburbs)
               29.9
                                       Q4:47.3
                       Windsor, Ontario, Canada
               Personal (median):
               0-24 h before clinical visit: 25.5
               0-6 h before clinical visit: 15.3
               7-12 h before clinical visit: 17
               13-18 h before clinical visit: 28.5
               19-24 h before clinical visit: 30.5
                      Personal (5th to 95th):
                      0-24 h before clinical visit: 9.8-133
                      0-6 h before clinical visit: 5.3-83.2
                      7-12 h before clinical visit: 7.1-186.3
                      13-18 h before clinical visit: 11.4-167
                      19-24 h before clinical visit: 10.1-148.2



Peters (2009, 191992)





Ruckerl (2007, 156931)



Steinvil (2008, 188893)

Helsinki, Finland
Stockholm, Sweden
Augsburg, Germany
Rome, Italy
Barcelona, Spain

Helsinki, Finland
Stockholm, Sweden
Augsburg, Germany
Rome, Italy
Barcelona, Spain
Athens, Greece
Tel Aviv, Israel
Helsinki: 17.1

Stockholm: 17.8
Augsburg: 33.1
Rome: 42.1

Barcelona: 40.7
Total: 30.3
17.1
17.8
33.1
42.1
40.7
38.5
64.5
Helsinki (range): 4-53

Stockholm (range): 0-57
Augsburg (range): 7-71
Rome (range): 15-91

Barcelona (range): 6-194
Total (range): 0-1 94
NR
NR
NR
NR
NR
NR
75th: 60.7
6.2.7.2.   Controlled Human Exposure Studies
      Several controlled human exposure studies were included in the 2004 PM AQCD (U.S. EPA,
2004, 056905) which evaluated markers of systemic inflammation following exposure to PM. Salvi
et al. (1999, 058637) exposed 15 healthy volunteers (21-28 yr) for 1 h to DE (300 ug/m3 particle
concentration) and observed a significant increase in neutrophils in peripheral blood 6 h post-
exposure compared with filtered  air control. However, Ohio et al. (2003, 087363) reported no
changes in plasma cytokine levels (e.g., IL-6 and TNF-a), WBC count, or CRP 0 or 24 h following a
2-h exposure to PM2.5 CAPs (120 ug/m3). Gong et al. (2003, 042106) did not observe any  effect of
PM2.5 CAPs (174 ug/m3) on serum amyloid A, while Frampton  (2001, 019051) reported no change in
leukocyte  activation following exposure to a low concentration (10 ug/m ) of UF carbon. The results
of studies published since the completion of the 2004 PM AQCD (U.S. EPA, 2004, 056905) are
discussed below.
December 2009
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      CAPS

      Several controlled human exposure studies have reported no change in plasma CRP levels
0-24 h after exposure to UF (avg concentration 50-100 ug/m3), PM25 (avg concentration 190 ug/m3),
or PM10_25 (avg concentration 89 ug/m3) CAPs (Gong et al., 2008, 156483; Graff et al, 2009,
191981; Mills  et al., 2008, 156766; Samet et al., 2009,  191913). In a study  of exposures to PM2.5
CAPs (200 ug/m3), Gong et al. (2004, 087964) observed increased peripheral basophils 4 h
following a 2-h exposure in a group of healthy older adults, which provides limited evidence of a
CAPs-induced systemic inflammatory response.


      Urban Traffic  Particles

      In a recent investigation of controlled exposures (24 h) to urban traffic particles, Brauner et al.
(2008, 191966) observed no effect of PM concentration  (avg PM2.5 concentration 10.5 ug/m3) on
markers of inflammation including CRP, IL-6 and TNF- a in peripheral venous blood.


      Diesel Exhaust

      Recent controlled human exposure studies have observed no effect of DE on plasma CRP
concentrations or peripheral blood cell counts (Blomberg  et al., 2005,  191991; Carlsten et al., 2007,
155714; Mills  et al., 2005, 095757; Mills et al., 2007, 091206; Tornqvist et al., 2007, 091279).
Mills et al. (2005,  095757) found no effect of DE (300 ug/mj) on serum IL-6 or TNF-a among
healthy adult volunteers 6 h after exposure. However, as reported by Tornqvist et al. (2007, 091279).
a significant increase  in these cytokines was observed 24 h after exposure. Although the
physiological significance of this finding is unclear, this study does provide evidence of a mild
systemic inflammatory response induced by exposure to DE. In an effort to better understand the
inflammatory response of exposure to PM, Peretz et al. (2007,  156853) conducted a pilot study in
which gene expression in peripheral blood mononuclear cells (PBMCs) of healthy human volunteers
was evaluated following a 2-h controlled exposure to DE (200  ug/m3 PM2 5). Adequate RNA samples
for microarray  analysis from both pre- and 4 h post-exposure to filtered air and DE were available in
4 of the 11 subjects enrolled. The authors found differential expression of 10 genes involved in the
inflammatory response when comparing DE exposure (8 upregulated, 2 downregulated) to filtered
air. Two participants had paired samples from 20 h post-exposure which were adequate for analysis.
At this time point, DE was associated with 4 differentially expressed genes (1 upregulated, 3
downregulated). However, this study is limited by a small  sample size with limited statistical power.


      Wood Smoke

      Barregard et al. (2006, 091381) recently reported an increase in serum amyloid A at 0, 3, and
20 h following a 4-h exposure to wood smoke (PM2 5 concentrations of 240-280  ug/m3) among a
group of 13 healthy adults (20-56 yr).


      Model Particles

      Frampton et al.  (2006, 088665) evaluated the effect of varying concentrations (10-50 ug/m3) of
UF EC on blood leukocyte expression of adhesion molecules in healthy and  asthmatic adults.
Healthy subjects (n = 40) were exposed for 2 h to filtered air and UF EC under three separate
protocols: 10 ug/m3 at rest (n = 12), 10 and 25 ug/m3 with  intermittent exercise (n = 12), and
50 ug/m3 with intermittent exercise (n = 16). Asthmatics (n = 16) were exposed at a single
concentration (10  ug/m3) for 2 h with intermittent exercise. Leukocyte expression of surface markers
were quantified using flow cytometry on peripheral venous blood samples collected prior to and
immediately following exposure, as well as at 3.5 and 21 h post-exposure. Among healthy resting
adults, UF EC exposure at a concentration of 10 ug/m3 had no effect on blood leukocytes. The
expression of adhesion molecules CD54 and CD 18 on monocytes, and CD 18 on PMNs was shown
December 2009                                  6-45

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to decrease with UF EC exposure in healthy exercising adults. In exercising asthmatics, expression
of CD lib on monocytes and eosinophils, as well as CD54 on PMNs were reduced following
exposure to UF EC. In both asthmatics and healthy adults, a UF EC-induced decrease in eosinophils
and basophils was observed 0-21 h following exposure. Although the clinical significance of these
findings is unclear, the authors concluded that their findings of UF EC-induced changes in leukocyte
distribution and expression were consistent with increased retention of leukocytes in the pulmonary
vasculature, which may be due to an increase in pulmonary vasoconstriction. Other studies have
reported no changes in plasma cytokine levels, peripheral blood counts, or CRP following exposure
to ZnO or UF EC (Beckett et al., 2005, 156261; Routledge  et al., 2006, 088674).


      Summary of Controlled Human Exposure Study Findings for Systemic
      Inflammation

     New studies involving controlled exposures to various particle types have provided limited
and inconsistent evidence of a PM-induced increase in markers of systemic inflammation.


6.2.7.3.   lexicological Studies

      There has been limited evidence that enhanced hematopoiesis may occur in animals exposed
to PM. Two studies in the 2004 PM AQCD (U.S. EPA, 2004, 056905) provided support for this
effect, with one study measured stimulated release of PMNs from bone marrow and another
examined peripheral blood PMN and blood cell counts; however, one study did not find associations
between CAPs and peripheral blood counts. Thus, it was concluded that consistent evidence of
PM-induced hematopoiesis remained to be demonstrated. However, in a study of humans exposed to
biomass burning during the 1997 Southeast Asian smoke-haze episodes, PMi0 demonstrated the best
relationship with blood PMN band cell counts expressed as a percentage of total PMN at lag 0 and 1,
indicating a relatively quick response (Tan  et al., 2000, 002304).


      CAPs

      A 2-day CAPs study employing SH rats did not report increased WBCs 18-20 h post-exposure
(Kodavanti et al., 2005, 087946). A study utilizing fine and/or UF CAPs demonstrated decreased
WBCs in SH rats 18 h after a 2-day (6 h/day) exposure (Kooter et al., 2006, 097547).  The decrease
was largely attributable to lowered neutrophils in the fine CAPs-exposed rats and reduced
lymphocytes in the fine+UF  CAPs-exposed animals.


      Model  Particles

      In a study of fine and UF CB particles (WKY rats; 7 h; mean mass concentration 1,400 and
1,660 ug/m3 for fine and UF CB, respectively; mean number concentration 3.8><103 and 5.2><104
particles/cm3, respectively), only UF CB induced elevated blood leukocytes at 0 and 48 h
post-exposure compared to the control  rats and no effect  was observed at 16 h (Gilmour et al., 2004,
054175). In another study of SH  rats exposed to UF carbon particles for 24 h (mass concentration
172 ug/m3; mean number concentration 9.0xl06 particles/cm3), the percent neutrophils and
lymphocytes were increased on the first recovery day, but not the third day (Upadhyay et al., 2008,
159345); CRP was unchanged. In another study, blood neutrophils were decreased in SH rats
exposed to UF CB for 6 h and no effects were observed in old F344 rats (Elder et al., 2004,
055642). Plasma IL-6 levels were unchanged (Elder et al., 2004, 055642).


      Coal Fly Ash

      Smith et al. (2006, 110864) examined the hematology parameters in SD rats following a 3-day
inhalation exposure (4 h/day) to coal fly ash (mean mass concentration 1,400 ug/m3) and reported
increased blood neutrophils and reduced blood lymphocytes at 36 h but not 18 h post-exposure.
December 2009                                 6-46

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      Intratracheal Instillation

      Elevated systemic IL-6 and TNF-a levels were observed following PMi0 instillation in mice
(details provided in Section 6.2.8.3) (Mutlu et al., 2007, 121441). IL-6 was decreased with PM
exposure in macrophage-depleted mice, indicating that some of the IL-6 release originated from
macrophages. For mice (male C57B1/6J) exposed to PMi0_2.5 derived from coal fly ash (200 ug),
increased plasma IL-6 levels were only observed in animals that also received 100 ug of LPS
(Finnerty  et al., 2007, 156434) and this response was not observed with LPS alone, indicating a role
for PM 10.2.5.


      Summary of lexicological Study Findings for Systemic Inflammation

      Overall, these studies provide evidence of time-dependent responses of systemic inflammation
induced by PM exposure. Alterations in WBCs have been reported generally as elevations
immediately (0 h) or <36 h post-exposure and no change or reductions are noted from 18-24 h.


6.2.8.   Hemostasis,  Thrombosis  and Coagulation Factors

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) presented limited and inconsistent evidence
from epidemiologic, controlled human exposure, and toxicological studies of PM-induced changes in
blood coagulation markers. The body of scientific literature investigating hemostatic effects of PM
has grown significantly since the publication of the 2004 PM AQCD (U.S. EPA, 2004, 056905). with
a limited number of epidemiologic studies demonstrating consistent increases in von Willebrand
factor (vWf) associated with PM and less consistent associations with fibrinogen. Recent controlled
human exposure and toxicological studies have also observed changes in blood coagulation markers
(e.g., fibrinogen, vWf, factor VII, t-PA) following exposure to PM. However, the findings of these
studies are somewhat inconsistent, which may be due in part to differences in the post-exposure
timing of the assessment.


6.2.8.1.   Epidemiologic Studies

      Several studies investigating the association of short-term fluctuations in PM concentration
with markers of coagulation (e.g., blood viscosity and fibrinogen) were included in the 2004 PM
AQCD (U.S. EPA, 2004, 056905). These preliminary studies offered limited support for mechanistic
explanations of the associations of PM concentration with heart disease outcomes. New studies,
published since 2002, are reviewed in this section. Only vWF and fibrinogen were measured in
enough comparable studies to allow the consistency of findings to be evaluated across epidemiologic
studies. Other markers of coagulation studied included D-dimer, prothombin time, Factor VII/VIII
and tPA.
      Liao et al. (2005, 088677) used a cross-sectional  study to examine the association between
short-term increases in air pollutant concentrations (mean PMi0, NO2, CO, SO2, and O3 over the
previous 3 days) and several plasma hemostatic markers (fibrinogen, factor VIII-C, vWF, albumin).
Study subjects were middle aged participants in the ARIC (Atherosclerosis Risk in Communities)
study  (n = 10,208), and were residents of Washington County, MD, Forsyth County, NC, selected
suburbs  of Minneapolis, MN, or Jackson, MS. Each 12.8 ug/m3 increase in the mean PMi0
concentration 1 day before the health measurements were made was associated with a 3.93%
increase in vWF (95% CI: 0.40-7.46) among diabetics,  but not among non-diabetics (-0.54% [95%
CI: -1.68 to 0.60]). Each 12.8 ug/m3 increase in the mean PMi0 concentration 1 day before the health
measurements were made was also associated with a 0.006 g/dL decrease in serum albumin
(95%  CI: -0.012 to 0.000) among those with cardiovascular disease (CVD), but not among those
without CVD (0.029 g/dL increase [95% CI:  -0.004 to 0.062]). The mean CO concentration on the
previous day was also associated with a significant decrease in serum albumin. The authors reported
significant curvilinear associations between PMi0 and factor VIII-C, which may indicate a threshold
effect. Similar curvilinear associations were observed between O3 with fibrinogen, and vWF, and
SO2 with factor VIII-C, WBC, and serum albumin (Liao et al., 2005, 088677). No significant
associations  with fibrinogen and PM10 or gaseous pollutants were observed.
December 2009                                  6-47

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      In the European multicity study described in Section 6.2.7.1, Ruckerl et al. (2007, 156931)
found that each 13.5 (ig/m3 increase in the mean PMi0 concentration over the previous 5 days was
associated with a 0.6% increase in the arithmetic mean fibrinogen level (95% CI: 0.1-1.1). Further
these investigators found that promoter polymorphisms within FGA and FGB modified the
association of 5-day avg PMi0 concentration with plasma fibrinogen levels (Peters  et al., 2009,
191992). This association was 8-fold higher among those homozygous for the minor allele genotype
of FGB rs!800790 compared with those homozygous for the major allele.
      Several smaller studies have been conducted in the U.S.  and Canada. Delfino et al. (2008,
156390) measured fibrinogen and D-dimer in blood of subjects who resided at two downtown Los
Angeles nursing homes. As described in Section 6.2.7.1, measurements were made over a period of
12 wk and subjects were >65 yr old with a history of coronary  artery disease. These markers were
not associated with the broad array PM metrics studied (e.g., PM0.25, PM0.25-2.5, PMi0_2.5, EC, OC,
primary OC, BC). In the study of 92 Boston residents with type 2 diabetes described previously,
O'Neill et al.  (2007, 091362) found that increases in mean PM2 5 and BC concentration were
associated with vWF concentrations for all moving averages examined (1-6 days). Reidiker et al.
(2004, 056992) reported that in-vehicle PM2.5 was associated with increased vWF over the next
10-14 h among nine police troopers. Sullivan et al. (2007, 100083) did not observe associations with
fibrinogen, or D-dimer in  individuals with or without  COPD. Red blood cells (RBCs), platelets,  nor
blood viscosity were associated with PM2 5 concentration in  a panel study of 88 non-smoking elderly
subjects residing in the Salt Lake City, Ogden and Provo metropolitan area of Utah (Pope et al.,
2004, 055238). Although Zeka et al. (2006, 157177) did not  observe an association with CRP in the
analysis of the Normative Aging Study population in Boston (Section 6.3.7.1), increased fibrinogen
level was associated with  increases in the number of particles/cm3 over the previous 48 h and 1 wk,
and an incremental increase in BC concentration over the previous 4 wk. There were no consistent
findings for lagged PM2.5  or sulfates (Zeka et al., 2006, 157177).
      Several studies of coagulation markers were conducted outside the U.S. and Canada. In a
study of healthy individuals in Taiwan, associations were observed for PM25, PMi0, nitrate, and
SO4 ~ concentrations with fibrinogen and plasminogen activator fibrinogen inhibitor-1 (PAI-1)
(Chuang  et al., 2007, 091063). In a large cross-sectional study of healthy subjects in Tel-Aviv,
Steinvil et al.  (2008, 188893) examined fibrinogen collected as part of routine health examinations
for 3,659 individuals. No  significant associations were found between pollutant levels (lagged
1-7 days) and fibrinogen.  Finally, Baccarelli and colleagues reported associations between PMi0 and
prothrombin time  among normal subjects (Baccarelli  et al.,  2007, 090733).


      Summary of Epidemiologic Study Findings for Hemostasis, Thrombosis and
      Coagulation

      The most commonly measured markers of coagulation in the studies  reviewed were fibrinogen
and vWF. Associations of PM10 (Liao et al., 2005, 088677) and PM2.5 (O'Neill  et al., 2007, 091362;
Riediker  et al., 2004, 056992) with increased vWF were observed across the limited number of
studies examining this association among both diabetics and healthy state troopers state troopers
(Liao et al., 2005, 088677: Riediker et al., 2004, 056992). Results for fibrinogen were not
consistent across epidemiologic studies. Positive associations with fibrinogen were reported in older
adults residing in Boston (Zeka et al., 2006, 157177)  and in the multicity European study of MI
survivors. Liao et  al. (2005, 088677) in a population based multicity study and Sullivan et al. (2007,
100083) did not observe associations of PMip or PM25 with fibrinogen. Several other markers have
been examined (e.g., D-dimer, prothrombin time), but not in adequate numbers of studies to allow
comparisons across epidemiologic studies. Mean and  upper percentile concentrations of the studies
discussed in this section are listed in Table 6-6.


6.2.8.2.   Controlled Human Exposure Studies

      In two separate studies conducted by Ohio and colleagues, controlled exposures (2 h) to fine
CAPs (Chapel Hill, NC) at concentrations between  15 and 350 ug/m3 were shown to increase blood
fibrinogen 18-24 h following exposure among healthy adults (Ohio et al., 2000, 012140; Ohio  et
al., 2003, 087363). Increases in blood fibrinogen or factor VII would suggest an increase in blood
coagulability, which could result in an increased risk of coronary thrombosis. However, a similar
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study conducted in Los Angeles observed a PM2.5 CAPs-induced decrease in factor VII blood levels
in healthy subjects and found no association between PM2.5 CAPs and blood fibrinogen among
healthy and asthmatic volunteers (Gong et al., 2003, 042106). Since the publication of the 2004 PM
AQCD (U.S. EPA, 2004, 056905). several new controlled human exposure studies have evaluated
the effects of PM on blood coagulation markers.


      CAPs

      Two studies of controlled human exposures to Los Angeles CAPs among older adults with
COPD (PM2.5 CAPs) and adults with and without asthma (UF CAPs) reported no significant
association between exposure and blood coagulation markers at 0, 4, or 22 h post-exposure (Gong  et
al., 2004, 087964: 2008, 156483). Graff et al. (2009, 191981) observed a decrease in the
concentration of D-dimer of marginal statistical significance in healthy adults (11.3% decrease per
10 ug/m3, p = 0.07) following exposure to PMi0_2.5 CAPs (89  ug/m3). At 20 h post-exposure, levels  of
tPA in plasma were shown  to decrease by 32.9% from baseline per 10  ug/m3 increase in CAPs
concentration. No other markers of hemostasis or thrombosis were affected by exposure to PMi0_2.5
CAPs. However, in a similar study from the same laboratory, Samet et al. (2009, 191913) reported  a
statistically significant increase in D-dimer immediately following, as well as 18 h, after a 2-h
exposure to UF CAPs (49.8 ug/m3; 120,662 particles/cm3) in  a group of healthy adults (18-35 yr).
Plasma concentrations of PAI-1 were also reported to increase 18 h after exposure to UF CAPs,
although this increase was  not statistically significant (p = 0.1). No changes in fibrinogen, tPA, vWF,
plasminogen, or factor VII  were observed. The finding of an increase in D-dimer following exposure
to UF CAPs provides potentially important information in elucidating the relationship between
elevated concentrations of  PM and cardiovascular morbidity and mortality observed in
epidemiologic studies. Whereas many coagulation markers provide evidence of an increased
potential to form clots (e.g., an increase in fibrinogen or a decrease in tPA), D-dimer is a degradation
product of a clot that has formed.


      Urban Traffic Particles

      In a study of controlled 24-h exposures to urban traffic particles (avg PM2.5 concentration
10.5 ug/m3) among 29 healthy adults, Brauner et al.  (2008, 191966) did not observe any particle-
induced change in plasma fibrinogen, factor VII, or platelet count after 6  or 24 h of exposure.
Similarly, Larsson et al. (2007, 091375) observed no change in PAI-1 or fibrinogen in peripheral
blood of healthy adult volunteers 14 h after a 2-h exposure to road tunnel traffic with a PM2.5
concentration of 46-81 ug/m3.


      Diesel Exhaust

      Mills and colleagues have recently demonstrated a significant effect of DE (particle
concentration 300 ug/m3) on fibrinolytic function both in healthy men (n  = 30) and in men with
coronary heart disease (n = 20) (Mills et al., 2005, 095757; 2007, 091206). In both groups of
volunteers, bradykinin-induced release of tPA was observed to decrease 6 h following exposure to
DE compared to filtered air exposure. The same laboratory did not observe an attenuation of tPA
release 24 h after a 1-h exposure to DE (300 ug/m3)  in a group of health adults (Tornqvist  et al.,
2007, 091279).  or observe  any change in markers of hemostasis or thrombosis 6 or 24 h following
DE exposure at the same particle concentration among a  group of older adults with COPD
(Blomberg et al., 2005, 191991). Carlsten et al. (2007, 155714) conducted a similar study involving
exposure of healthy adults  to DE with a PM2.5 concentration of 200 ug/m3. Although the authors
observed an increase in D-dimer, vWF, and platelet count 6 h following exposure to DE, these
increases did not reach statistical significance. In a subsequent study with a similar study design, the
same laboratory found no effect of a 2-h exposure to DE  (100 and 200 ug/m3 PM25) on
prothrombotic markers in a group (n = 16) of adults  with metabolic syndrome (Carlsten et al., 2008,
156323). The authors postulated that the lack  of significant findings could be due to a relatively
small sample size. In addition, Carlsten et al. (2007,  155714;  2008, 156323) exposed subjects at rest
December 2009                                 6-49

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while Mills et al. (2005, 095757) exposed subjects to a higher concentration (300 ug/m3) with
intermittent exercise. A more recent study of DE which exposed healthy adults to a slightly higher
particle concentration (330 ug/m3) evaluated the effect of DE on thrombus formation using an ex
vivo perfusion chamber (Lucking et al., 2008, 191993). Thrombus formation, as well as in vivo
platelet activation, was observed to significantly increase 2 h following exposure to DE relative to
filtered air, thus providing some evidence of a potential physiological mechanism which may explain
in part the associations between PM and cardiovascular events observed in epidemiologic studies.


      Wood Smoke

      Barregard et al. (2006, 091381) recently evaluated the effect of wood smoke on markers  of
coagulation, inflammation, and lipid peroxidation. Subjects (n = 13) were healthy males and females
(20-56 yr) and were exposed for 4 h to PM2.s concentrations of 240-280 ug/m3. The authors reported
an increase in the ratio of factor VIII/vWF, which is an indicator of an increased risk of venous
thromboembolism, at 0, 3, and 20 h following exposure to wood smoke.


      Model Particles

      Routledge et al. (2006, 088674) did not observe any changes in fibrinogen or D-dimer
following a 1-h  exposure to UF carbon among a group of resting healthy older adults and older
adults with stable angina. Similarly, Beckett et al. (2005, 156261) found no changes in hemostatic
markers (e.g., factor VII, fibrinogen, and vWF) following exposure to UF and fine ZnO  (500 ug/m3).


      Summary of Controlled Human Exposure Study Findings for Hemostasis,
      Thrombosis and Coagulation

      Taken together, these new studies have provided some additional evidence that short-term
exposure to PM at near ambient levels may have small, yet statistically significant effects on
hemostatic markers in healthy subjects or patients with coronary artery disease.


6.2.8.3.   lexicological Studies

      In general, the limited toxicological studies reviewed in the 2004 PM AQCD (U.S. EPA,  2004,
056905) reported positive and negative findings for plasma fibrinogen levels or other factors
involved in the coagulation cascade. Rats exposed to New York City  CAPs did not have any
exposure-related effects on any measured coagulation markers (Nadziejko et al., 2002, 050587).
whereas rats exposed to a high concentration of ROFA demonstrated increased plasma fibrinogen
(Kodavanti et al., 2002, 025236).


      CAPs

      APM2.5 CAPs exposure conducted for 2 days (4 h/day; mean mass concentration
144-2,758 ug/m3; 8-10/2001; RTP, NC) in SH rats induced plasma fibrinogen increases (measured
18-20 h post-exposure) in 5 of 7 separate studies (Kodavanti  et al., 2005, 087946). Fibrinogen  was
not different from the air control group on the two days with the highest CAPs concentrations (1,129
and 2,758 ug/m3), indicating that the response was likely not attributable to mass alone.
      In SH rats exposed to PM2.5 CAPs for 6 h in one of three locations in the Netherlands (mean
mass concentration range 270-2,400; 335-3,720; and 655-3,660 ug/m3), plasma fibrinogen was
increased 48 h post-exposure when all CAP-exposed animals were combined in the analysis (Cassee
et al., 2005, 087962). In WKY rats  pre-exposed to O3 (8 h; 1,600 ug/m3) and CAPs for 6 h, increases
in RBCs, hemoglobin, and hematocrit were observed 2 days after CAPs exposure. For SH rats
exposed to CAPs only, decreased mean corpuscular hemoglobin concentration were reported.
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      A similar study conducted by the same group (Kooter et al., 2006, 097547) reported no
changes in plasma fibrinogen measured 18 h after a 2-day exposure (6 h/day) to PM2.5 or PM2.5+UF
CAPs (mean mass concentration range 399.0-1,067.5 and 269.0-555.8 ug/m , respectively; 1/2003-
4/2004). However, elevated vWF was observed in SH rats exposed to the highest concentration of
PM2.5 CAPs. Decreases in mean corpuscular volume (MCV), and elevations in mean platelet volume
(MPV) and mean platelet component (MPC) were reported in SH rats 18 h following a 2-day
exposure to PM2.5+UF CAPs in a freeway tunnel.


      Traffic-Related Particles

      Plasma fibrinogen  levels were elevated 18 h following a single 6-h exposure to on-road
highway aerosols when groups of rats pretreated with saline or influenza virus were combined
(i.e., there was a significant effect of particles) (Elder et al., 2004, 087354).


      Model  Particles

      The coagulation effects of inhaled UF CB at a concentration of 150 ug/m3 (number count not
provided) for 6 h were evaluated 24 h post-exposure in two aged rat models (11-14 mo SH and 23
mo F344), some of which received LPS via intraperitoneal injection prior to particle exposure (Elder
et al., 2004, 055642). LPS has been shown to induce the expression of molecules involved in
coagulation, inflammation, oxidative stress, and the acute-phase response. In those animals only
exposed to CB, SH rats demonstrated increased thrombin-anti-thrombin complexes (TAT) and
decreased fibrinogen. For F344 rats, TAT complexes and fibrinogen were elevated only in those that
received LPS and CB. Whole-blood viscosity was not altered in either rat strain with particle
exposure.
      In another study of SH rats exposed to UF carbon particles for 24 h (mass concentration 172
ug/m3; mean number concentration 9.0xl06 particles/cm ), the number of RBCs and platelets  and
hematocrit percent, were unchanged 1 and 3 days following exposure (Upadhyay et al., 2008,
159345). Fibrinogen levels were similar in both air and UF carbon-exposed groups. However,
mRNA expression of PAI-1 and TF in lung homogenates (but not in heart) was increased on
recovery day 3 after  exposure. A study of similar design that employed SH rats did not report any
effect on plasma fibrinogen 4 or 24 h following UF carbon exposure (mass concentration 180 ug/m3;
mean number concentration 1.6><107 particles/cm3) (Harder  et al., 2005, 087371). Similarly, clotting
factor Vila and thrombomodulin, PAI-1, and tPA mRNA expression were not affected by UF carbon
exposure at 24 h post-exposure.


      Coal Fly Ash

      One study that employed coal fly ash (mean mass concentration 1,400 ug/m3; 4 h/day><3 days)
demonstrated increases in hematocrit and MCV in SD rats at 36 h but not 16 h post-exposure (Smith
etal, 2006, 110864).


      Intratracheal Instillation

      Mutlu et al. (2007, 121441) used a PM10 sample collected from Dusseldorf, Germany, in mice
(C57BL/6) with and without the gene coding for IL-6. The authors report using a moderate IT
instillation dose (10  ug/mouse; roughly equivalent to 400-500 ug/kg); the PM sample had previously
been characterized as having significant Fe, Ni, and V content (Upadhyay et al., 2003, 097370).  In
C57BL/6 mice, the Dusseldorf PM shortened bleeding (32%), prothrombin  (13%), and activated
partial thromboplastin (16%) times and increased platelet count, fibrinogen, and Factors II, VIII,  and
X activities 24 h following exposure. The authors further demonstrated accelerated coagulation by a
reduction in the left carotid artery occlusion time (experimentally-derived by direct application of
FeCl3). Additional experiments demonstrated that IL-6"7" or macrophage-depleted mice showed
dramatically attenuated effects of PMi0 on hemostatic indices, thrombin generation, and occlusion
December 2009                                  6-51

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time. In IL-6"7" mice, there was no change in total cell counts or differentials in BALF compared to
the wild-type mice, despite the lack of IL-6. In contrast, the model of macrophage depletion had
reduced levels of macrophages and IL-6 in BALF, following PM exposure. These studies suggest
that instillation of Dusseldorf PMi0 activates clotting through an alveolar macrophage-dependent
release of IL-6; however, other factors may also be involved in the prothrombotic response
(i.e., activation of neutrophils, other inflammatory cells, or alterations in the levels of other
cytokines).
      In a study employing PMi0_2.5 collected from six European locations with contrasting traffic
profiles, fibrinogen increases were observed in SH rats exposed to 10 mg/kg via IT instillation at 24
h post-exposure and similar responses were observed with PM2.5  (Gerlofs-Nijland et al, 2007,
097840). PMio_2.5 and PM2.5 samples from Prague or Barcelona administered intratracheally to SH
rats (7 mg/kg) resulted in elevated plasma fibrinogen levels 24 h post-exposure compared to rats
instilled with water (Gerlofs-Nijland et al., 2009, 190353). No changes were observed in vWF  for
whole particle suspensions, but Barcelona PMi0_2.5 organic extract induced greater levels of vWF
than Barcelona PMio-2.5-


      Summary of lexicological Study Findings for Hemostasis, Thrombosis and
      Coagulation

      Increases in coagulation and thrombotic markers were observed in some studies of rats or mice
exposed to PM. Plasma TAT complexes were increased in CB-exposed SH rats and shortened
bleeding, prothrombin, and activated partial thromboplastin times were  observed in mice exposed
via IT instillation to PMi0. Furthermore, the latter study also reported increased levels of Factors II,
VIII, and X activities in mice. Another study demonstrated increased vWF in response to PM2.5
CAPs. As for plasma fibrinogen, these studies provide some evidence that increased levels are
observed 18-48 h post-exposure to PM, although one study reported no  change and another reported
a decrease in this biomarker. Alterations in platelet measurements have also been observed with PM
exposure, including increased platelet number, mean platelet volume, and mean platelet component.
The toxicological results of RBC-related measurements are limited and  inconsistent following PM
exposure, which may be attributable to different exposure protocols, time of analysis, or rat strain.


6.2.9.   Systemic and Cardiovascular Oxidative  Stress

      Very little information on systemic oxidative stress associated with PM was available for
inclusion in the 2004 PM AQCD (U.S. EPA, 2004, 056905). However, recent epidemiologic studies
have provided consistent evidence of PM-induced increases in markers  of systemic oxidative stress
including plasma thiobarbituric acid reactive substances (TEARS), CuZn-super oxide dismutase
(SOD),  8-oxo-7-hydrodeoxyguanosine (8-oxodG), and total homocysteine. This is supported by a
limited number of controlled human exposure studies that observed PM-induced increases in free-
radical mediated lipid peroxidation, as well as upregulation of the DNA repair gene hOGGl. In
addition, recent toxicological studies have demonstrated an increase in cardiovascular oxidative
stress following PM exposure in  rats.


6.2.9.1.  Epidemiologic Studies

      No studies of markers of oxidative stress were reviewed in the 2004 PM AQCD (U.S. EPA,
2004, 056905). Since 2002, numerous studies have examined whether short-term increases in mean
PM concentrations are associated with changes in systemic markers of oxidative stress.
      In an analysis of the randomized trial of omega-3 fatty acid supplementation in Mexico City
nursing home residents described previously (Section 6.2.1.1), Romieu  et al. (2008,  156922)
investigated the effect of this intervention on markers of systemic oxidative stress (Cu/Zn SOD
activity, LPO in plasma and GSH in plasma). A significant decrease of Cu/Zn SOD was associated
with a 10 ug/m3 increase of PM2.5 in both groups (Fish oil: (3 = -0.17 [SE = 0.05], p = 0.002; Soy oil:
(3 = -0.06 [SE = 0.02], p <0.001). A decrease in GSH was associated with a 10 ug/m3 increase in
PM2.5 in the fish oil group ((3 = -0.09  [SE = 0.04], p = 0.017).
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      Two studies evaluated plasma homocysteine levels in relation to PM. Baccarelli et al. (2007,
091310) investigated fasting and post-methionine load total homocysteine (tHcy) among 1,213
normal subjects in Lombardia, Italy. Plasma homocysteine is a risk factor for CVD and a marker for
oxidative stress. Among smokers, average PMi0 level during the 24 h preceding the measurement
was associated with 6.3% (95% CI: 1.3-11.6) and 4.9% (95% CI: 0.5-9.6) increases in fasting and
post-methionine load tHcy, respectively. No associations were observed among non-smokers. Park
et al. (2008, 156845) investigated the association of BC, OC, SO42~ and PM2.5 with tHcy among 960
male participants of the Normative Aging Study. Effect modification by folate and vitamins B6 and
B12 was also examined. BC and OC were associated with increases in tHcy and associations were
more pronounced in those with lower plasma folate and vitamin B12.
      In smaller studies with 25-50 healthy or diseased participants, several markers of oxidative
stress have been associated with PM size fractions or components. These associations include
TEARS with 24-h PMi0 (Liu et al., 2006, 192002); Cu/Zn-SOD with several PM metrics (e.g., UF,
PMio-zs, EC, OC, BC and PNC) (Delfino et al., 2008,  156390): PM2.5, BC, V and Cr with plasma
proteins (Sorensen  et al., 2003, 157000); DNA damage assessed by 8-oxodG in lymphocytes
(Sorensen et al., 2003, 157000). and 8-OHdG with sulfates (Chuang et al., 2007, 091063). In
addition, a cross-sectional study of children (10-18 yr) in Iran showed an association of PMi0 with
oxidized LDL (oxLDL), malondialdehyde (MDA) and conjugated diene (CDE) (Kelishadi  et al.,
2009, 191960).


      Summary of Epidemiologic Study Findings for Systemic and Cardiovascular
      Oxidative Stress

      Oxidative stress responses measured by one or more markers (plasma tHcy, CuZn-SOD,
TEARS, 8-oxodG, oxLDL and MDA) have been consistently observed (Baccarelli et al.,  2007,
091310: Chuang et al., 2007, 091063: Delfino et al., 2008, 156390: Kelishadi et al., 2009, 191960:
Liu et al., 2007, 156705: Romieu et al., 2008, 156922: Sorensen et al., 2003, 157000). In addition,
a series of analyses examining the modification the PM-HRV association by genetic polymorphisms
related to oxidative stress has provided insight into the possible mechanisms of CVD observed in
association with PM concentrations (Section 6.2.1.1). Mean and upper percentile concentrations of
the epidemiologic studies of systemic oxidative stress are included in Table 6-6.
6.2.9.2.   Controlled Human Exposure Studies


      Urban Traffic Particles

      Brauner et al. (2007, 091152) recently investigated the effect of urban traffic particles on
oxidative stress-induced damage to DNA. Healthy adults (20-40 yr) were exposed to low
concentrations of urban traffic particles as well as filtered air for periods of 24 h, with and without
two 90-min periods of exercise. Exposures took place in an exposure chamber above a busy road
with high traffic density in Copenhagen. Non-filtered air was pumped into the chamber from above
the street, with avg PM25 and PMi0_2.5 mass concentrations of 9.7 ug/m3 and 12.6 ug/m3,
respectively. The UF/PM2.5 (6-700 nm) particle number concentration was continuously monitored
throughout the exposure (avg PNC 10,067 particles/cm3). The PM2.5 fraction was rich in sulfur, V,
Cr, Fe, and Cu. PBMCs were isolated from blood samples collected at 6 and 24 h. DNA damage, as
measured by strand breaks (SB) and formamidopyrimidine-DNA glycosylase (FPG) sites, was
evaluated using the Comet assay. The activity and mRNA levels of the DNA repair enzyme
7,8-dihydro-8-oxoguanine-DNA glycosylase (OGG1) were also measured. The authors observed
increased levels of DNA strand breaks and FPG sites following 6 and 24 h of exposure to PM. Using
a mixed-effects regression model, the particle concentration at the 57 nm mode was found to be the
major contributor of these measures of DNA damage. The results of this study suggest that short-
term (6-24 h) exposure to  ambient levels of UFPs cause systemic oxidative stress resulting in
damage to DNA.
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      Diesel Exhaust

      Tornqvist et al. (2007, 091279) reported an increase in plasma antioxidant capacity in a group
of healthy volunteers 24 h after a 1-h exposure to DE with a particle concentration of 300 ug/m3. The
investigators suggested that systemic oxidative stress occurring following exposure may have caused
this up-regulation in antioxidant defense. Peretz  et al. (2007, 156853) observed some significant
differences in expression of genes involved in oxidative stress pathways between exposure to DE
(200 ug/m3 PM25) and filtered air. However, the conclusions of this investigation are limited by a
small number of subjects (n = 4).


      Wood Smoke

      In a controlled human exposure study of controlled exposure to wood smoke, Barregard et al.
(2006, 091381) found an increase in urinary excretion of free 8-iso-prostaglandin2a among healthy
adults (n = 9) approximately 20 h following a 4-h exposure to PM2 5 (mass concentration of
240-280 ug/m3). This finding provides evidence of a PM-induced increase in free-radical mediated
lipid peroxidation. From the same study, Danielsen et al. (2008, 156382) reported an increase in the
mRNA levels of the DNA repair gene hOGGl in peripheral mononuclear cells 20 h after exposure to
wood smoke relative to filtered air.


      Summary of Controlled Human Exposure Study Findings for Systemic and
      Cardiovascular Oxidative Stress

      Based on the results of these studies, it appears that exposure to PM at or near ambient levels
may increase systemic oxidative stress in human subjects.


6.2.9.3.   Toxicological Studies

      Very little information was available for inclusion in the 2004 PM AQCD (U.S. EPA, 2004,
056905) on oxidative stress in the cardiovascular system. A few new studies have evaluated ROS in
blood or the heart following PM exposure. Some studies have used chemiluminescence (CL), which
is measured using the decay of excited states of molecular oxygen, and may also be prone to artifact.


      CAPS

      Gurgueira et al. (2002,  036535) measured oxidative stress in SD rats immediately following a
5-h CAPs  exposure (PM2.5 mean mass concentration 99.6-957.5 ug/m3; Boston, MA; 7/2000-2/2001)
and reported increased in situ CL in hearts of CAPs-exposed animals. CL evaluated after 1- and 3-h
CAPs exposure did not demonstrate changes from the filtered air group, although a 5-h exposure
resulted in increased CL in hearts. When animals were allowed to recover for 24 h, oxidative stress
returned to control values. To compare potential  particle-induced differences in CL, rats were
exposed to ROFA (1.7 mg/m3 for 30 min) or CB (170 ug/m3 for 5 h) and only the ROFA-treated
animals exhibited increased CL in cardiac tissue. Additionally, levels of antioxidant enzymes in the
heart (Cu/Zn-SOD and MnSOD) were increased in CAPs-exposed rats. Individual PM component
concentrations were linked to CL levels in rat heart tissue using separate  univariate linear regression
models, with total PM mass, Al, Si, Ti, and Fe having p-values < 0.007 (Gurgueira et al., 2002,
036535). The highest R2 value in the regression analyses was for Al (0.67) and its concentration
ranged from 0.000 to 8.938 ug/m3.
      Recently, Rhoden et al. (2005, 087878) tested the role of the ANS in driving CAPs-induced
cardiac oxidative stress in heart tissues of SD rats. At PM2.5 mass concentrations of 700 ug/m3
(Boston, MA), pretreatment with an antioxidant, a Pi-receptor antagonist, or a muscarinic receptor
antagonist attenuated the CL and TEARS effects observed in the heart following a 5-h PM2.5
exposure. The wet/dry ratio (edema) of cardiac tissue also returned to control  values in animals
treated with the antioxidant prior to CAPs. These combined results indicate involvement of both the
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sympathetic and parasympathetic pathways in the cardiac oxidative stress response observed
following PM exposure.
      More recently, a type of irritant receptor, the transient receptor potential vanilloid receptor 1
(TRPV1), was identified as central to the inhaled CAPS-mediated induction of cardiac tissue CL and
TEARS in SD rats (Ghelfi  et al., 2008, 156468). In these studies (PM2.5 mean mass concentration
218 ug/m3; Boston, MA), capsazapine (aTRPVl inhibitor) abrogated cardiac CL, TEARS, edema,
and QT-interval shortening when measured at the end of the 5-h exposure. These studies provide
some evidence that the ANS may be involved in producing cardiac oxidative stress following
exposure to CAPs. Furthermore, this response could be acting, at least in part, via TRPV receptors.
      In WKY rats exposed to PM2.5 CAPs in Japan, relative mRNA expression of HO-1 was
increased in cardiac tissue and was also significantly correlated with the cumulative mass of PM
collected on chamber filters throughout the exposure (Ito  et al.,  2008, 096823).


      Road Dust

      A composite of PM2.5 road dust samples obtained from New York City, Los Angeles, and
Atlanta induced cardiac ROS as measured by CL in the low exposure group (306 ug/m3) and TEARS
in the high exposure group (954 ug/m3); thus, the CL and TEARS methods provided different results
for the various source types (Seagrave et al., 2008, 191990).


      Gasoline and  Diesel Exhaust

      Gasoline exhaust exposure also resulted in increased ROS (measured by TEARS) in aortas of
ApoE"7" mice, as discussed in Section 6.2.4.3 (Lund et al., 2009, 180257).  Similarly, a 6-h exposure
to gasoline exhaust (PM mass concentration 60  ug/m3, CMD 15-20 nm; MMD 150 nm; CO
concentration 104 ppm, NO concentration 16.7 ppm, NO2 concentration 1.1 ppm, SO2 concentration
1.0 ppm) in SD rats demonstrated increased CL in the heart, but no change in TEARS and the CL
response was not duplicated when the particles were filtered (Seagrave et al., 2008, 191990).
Increased lipid peroxides in the serum of male SH rats exposed to gasoline exhaust (PM mass
concentration 59.1 ug/m3; NO concentration 18.4 ppm; NO2 concentration 0.9 ppm; CO
concentration 107.3 ppm; SO2 concentration 0.62 ppm) was observed following a 1-wk exposure to
gasoline exhaust and this effect was attenuated with particle filtration (Reed et al., 2008, 156903).
An IT instillation study of diesel particles in mice demonstrated increased myocardial MPO activity
12 and 24 h post-exposure to the residual particle component that remained after extraction with
dichloromethane (Yokota et al., 2008, 190109).


      Model Particles

      Other studies previously presented also demonstrated ROS (via CL) and NT expression (via
ELISA) in the left ventricle with CB exposure (Tankersley et al., 2008, 157043) and oxidative stress
in the systemic microvasculature following TiO2 inhalation (Nurkiewicz et al., 2009, 191961) or
ROFA IT instillation exposure (Nurkiewicz  et al., 2006, 088611). Decreased HO-1 mRNA
expression in hearts of SH rats exposed to UF carbon particles was observed 3 days following
exposure (Upadhyay  et al., 2008, 159345) and there was  a trend toward increased HO-1 mRNA
expression 1 day post-exposure.


      Summary of lexicological Study Findings for Systemic and Cardiovascular
      Oxidative Stress

      When considered together, the above studies provide evidence that PM exposure results in
oxidative stress as measured in cardiac tissue by CL, TEARS, HO-1 mRNA expression, and NT
expression.  However, the PM concentration/dose and method of ROS measurement could also affect
the response. Cardiac oxidative stress may have resulted from PM stimulation of the ANS, although
these studies have only been conducted in one laboratory. Multiple studies from two different
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laboratories provide support for vascular oxidative stress as demonstrated in aortas following
gasoline exhaust exposure and in the microvasculature after TiO2 inhalation or ROFA IT exposure.


6.2.10. Hospital Admissions and Emergency Department Visits

      The 1996 PM AQCD (U.S. EPA, 1996, 079380) considered just two time-series studies
regarding the association between daily variations in PM levels and the risk of CVD morbidity as
measured by the number of daily hospitalizations with primary discharge diagnoses related to CVD
(Burnett et al., 1995, 077226; Schwartz and Morris,  1995, 046186). In contrast, the 2004 PM
AQCD (U.S. EPA, 2004, 056905) reviewed more than 25 publications relating PM and risk of CVD
hospitalizations.  Results from a handful  of larger multicity studies were emphasized, with the
greatest emphasis placed on findings from the U.S. National Morbidity, Mortality, and Air Pollution
Study (NMMAPS) (Samet et al., 2000, 010269) and a subsequent reanalysis (Zanobetti and
Schwartz, 2003,  157174). The NMMAPS study evaluated the effect of daily changes in ambient PM
levels on total CVD hospitalizations among elderly Medicare beneficiaries in  14 U.S. cities and
found a ~1% excess risk per 10 (ig/m3 increase in PMi0. The 2004 PM AQCD concluded that these
results, along with those of the other single- and multicity studies reviewed "generally appear to
confirm likely excess risk of CVD-related hospital admissions for U.S. cities in the range of
[0.6-1.7% per 10 (ig/m3] PM10, especially among the elderly" (U.S. EPA, 2004, 056905). The 2004
PM AQCD (U.S. EPA, 2004, 056905) also concluded that there was some evidence from single-city
studies suggesting an excess risk specifically for hospitalizations related to IHD and heart failure.
Furthermore, the 2004 PM AQCD (U.S. EPA, 2004, 056905) found that "insufficient data exist  from
the time-series CVD admissions studies  [... ] to provide clear guidance as to which ambient PM
components, defined on the basis of size or composition, determine ambient PM CVD effect
potency" (U.S. EPA, 2004, 056905). The key studies reviewed in the 2004 PM AQCD (U.S. EPA,
2004, 056905) on this topic included those by Burnett and colleagues (1997, 084194; 1999, 017269).
Lippman and colleagues (2000, 011938). Ito (2003, 042856). and Peters et al.  (2001, 016546).
      Recent large studies conducted in the U.S., Europe, and Australia and New Zealand have
confirmed these  findings for PMi0, and have also observed consistent associations between PM2.5
and cardiovascular hospitalizations. However, findings from single-city studies have demonstrated
regional heterogeneity in effect estimates. It is apparent from these recent studies that the observed
increases in cardiovascular hospitalizations are largely due to admissions for IHD and CHF rather
than CBVDs (such as stroke). The new literature on hospitalizations and ED visits for cardiovascular
causes published since 2002 is reviewed in the following sections. First, the specific CVD outcomes
captured using ICD codes from hospital  admissions databases are discussed. Second, the methods
used in the large and multicity studies are described. For each outcome considered, evidence from
large/multicity studies is emphasized and results from U.S.  and Canadian single-city studies are also
discussed. Although the single-city studies may lack statistical power needed to  evaluate interactions
and detect some  of the subtle effects of air pollution, they inform the interpretation of the
heterogeneous effect estimates that have been observed across North America.


      Cardiovascular Disease ICD Codes

      When the 2004 PM AQCD (U.S. EPA, 2004, 056905) was written, few  studies had evaluated
the link between ambient PM and specific CVD outcomes such as CHF, IHD or ischemic stroke. In
contrast, the majority of recent studies have focused on specific CVD outcomes. This trend is
justified by the fact that the short-term exposure effects of PM may be very different for different
cardiovascular outcomes. For example, given the current putative biological pathways involved in
the acute response to PM exposure, there is no a priori reason why short-term fluctuations in PM
levels would have similar effects on the risk of acute MI, chronic atherosclerosis of the coronary
arteries, and hemorrhagic stroke.
      Almost all of the published time-series studies of cardiovascular hospitalizations and ED  visits
identified cases based on administrative  discharge diagnosis codes as defined by the International
Classification  of Disease 9th revision (ICD-9) or 10th revision (ICD-10) (NCHS, 2007, 157194). A
complicating factor in interpreting the results of these studies is the lack of consistency in both
defining specific health outcomes and in the nomenclature used.
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Table 6-7.     Description of ICD-9 and ICD-10 codes for diseases of the circulatory system.
Description
All Cardiovascular Disease
IHD
Acute Ml
Diseases Of Pulmonary Circulation
CHF
Arrhythmia
CBVD
Ischemic Stroke And Transient Ischemic Attack (TIA)
Hemorrhagic Stroke
Peripheral Vascular Disease (PVD)
ICD-9 Codes
390-459
410-414
410
415-417
428
427
430-438
430-432
433-435
440-448
ICD-10 Codes
IOO-I99
I20-I25
121
I26-I28
ISO
I47, I48, I49
I60-I69
I63
I60-I62
I70-I79
      Table 6-7 shows major groups of diagnostic codes used in air pollution studies for diseases of
the circulatory system. The codes ICD-9: 390-459 are frequently used to identify all CVD morbidity.
Note that this definition of CVD includes diseases of the heart and coronary circulation, CBVD, and
peripheral vascular disease. In contrast, the term cardiac disease specifically excludes diseases not
involving the heart or coronary circulation. While this distinction is conceptually straightforward, the
implementation of the definition of cardiac disease in terms of ICD-9 or ICD-10 codes varies among
authors. Even greater heterogeneity can be found among studies in the implementation of definitions
related to CBVD.


      Design and Methods of Large and Multicity Hospital Admission and ED Visit
      Studies

      Recently, multiple research groups in the U.S., Europe, and Australia have created large
datasets to evaluate specific CVD and respiratory endpoints using more detailed and relevant
measures of PM concentration. In the U.S., the MCAPS analyses of Dominici et al. (2006,  088398).
Bell et al. (2008, 156266) and Peng et al. (2008, 156850) are large, comprehensive and informative
studies based on Medicare hospitalization data. Likewise, the Atlanta-based SOPHIA study (Metzger
et al., 2004, 044222;  Peel et al., 2005,  056305; Tolbert et al., 2007, 090316) is the largest  and most
comprehensive study of U.S. cardiovascular and respiratory ED visits. In Europe, the APHEA
initiative (Le  et al., 2002, 023746; Le  et al., 2003, 042820) the more recent HEAPSS study (Von  et
al., 2005, 088070). and the French PSAS program (Host et al., 2008, 155852; Larrieu et al., 2007,
093031) are similarly noteworthy for their large sample size, geographic diversity, and consideration
of specific CVD and/or respiratory endpoints. These studies contain adequate data to examine
interactions by season and region; the effects of different size fractions, components and sources of
PM; or the  effect of PM on susceptible populations. The following section provides a detailed review
of the study design and methods used by each of the large studies. A discussion of the results of each
study can be found later in Section 6.2.10.

      MCAPS; Medicare Air Pollution  Study

      Dominici et al. (2006, 088398) created a database of daily time-series of hospital admission
rates (1999-2002) for a range of cardiovascular and respiratory outcomes among Medicare
beneficiaries aged >65 yr, ambient PM2.5 levels, and meteorological variables for 204 U.S.  urban
counties. The specific CVD outcomes considered were: CBVD (ICD-9:  430-438), peripheral
vascular disease (440-448), IHD (410-414, 429), heart rhythm disturbances (426, 427), and CHF
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(428). Injuries (800-849) were evaluated as a control outcome. Gaseous and other particulate
pollutant size fractions were not considered.
      Data on PM2.5 were obtained from the AQS database of the U.S. EPA. Within each county,
associations between cause-specific hospitalization rates and same-day PM2.5 levels were evaluated
using Poisson regression models controlling for long-term temporal trends and meteorologic
conditions with natural cubic splines. County-specific results were subsequently averaged using
Bayesian hierarchical models. In addition to evaluating single-day lags, 3-day distributed lag models
(lags 0,  1, and 2 days) were also considered in a subset of 90 U.S. counties with daily PM2.5 data
available during the study time period.
      Subsequently, Peng et al. (2008, 156850) and Bell et al. (2008,  156266) extended the database
of daily time-series of hospital admissions, PM25, and other covariates for 202 U.S. counties through
2005. Importantly, Peng et al.  (2008, 156850) added data on PMi0.2.5 to this database for 108 U.S.
counties with one or more co-located PM25 and PM10 monitors. Analyses with PM10_25 were carried
out using similar methods to those of Dominici et al.  (2006, 088398). Peng et al. (2008, 156850)
evaluated the robustness of PM25 associations to adjustment for PMi0_2.5 (Peng et al., 2008, 156850).
Gaseous pollutants were not considered in these analyses.

      SOPHIA: Study of Particulates and Health in Atlanta

      SOPHIA investigators (Metzger et al.. 2004. 044222: Peel et al., 2005, 056305; Tolbert et
al., 2000, 010320) compiled data on 4,407,535 ED visits between 1993 and 2000 to 31 hospitals in
the Atlanta metropolitan statistical area (20 counties). Specific cardiovascular outcomes considered
were: IHD (ICD-9: 410-414),  acute MI (410), cardiac dysrhythmias (427), cardiac arrest (427.5),
CHF (428), peripheral vascular and CBVD (433-437, 440, 443-444, 451-453), atherosclerosis (440),
and stroke (436). Finger wounds (883.0) were evaluated as a control outcome.
      The air quality data included measurements of criteria pollutants (PM and gaseous pollutants)
for the entire study period, as well as detailed measurements of mass concentrations for PM25 and
PM10_2.5 and several physical and chemical characteristics of PM25 for the final 25 mo of the study
using data from the ARIES monitoring station. Rates of ED visits for specific causes were assessed
in relation to the 3-day ma (lags 0-2 days) of daily measures of air pollutants using Poisson
generalized linear models (GLMs) controlling for long-term temporal trends and meteorologic
conditions with cubic splines.  Tolbert et al. (2007, 090316) published interim results of this study in
relation to both cardiovascular and respiratory disease visits, Metzger et al. (2004, 044222)
published the main results for CVD visits, and Peel et al. (2005, 056305) published the main results
for respiratory conditions. An  analysis of co-morbid conditions that may make individuals more
susceptible to PM-related cardiovascular risk was carried out by Peel  et al. (2007, 090442). Tolbert
et al. (2007, 090316) extended the available data through 2002 and compared results from single and
multipollutant models, while Sarnat et al. (2008, 097972) evaluated the risk of ED visits for
cardiovascular and respiratory diseases in relation to  specific sources  of ambient PM using the
extended dataset.

      APHEA andAPHEA-2: Air Pollution and Health: a European Approach

      APHEA-2 investigators compiled daily data on cardiovascular (Le  et al., 2002, 023746; 2003,
042820) and respiratory  (Atkinson  et al., 2001, 021959; 2003, 042797) disease hospital admissions
in the following 8 European locations: Barcelona, Birmingham, London, Milan, the Netherlands
(considered a "city" for this study, due to its small size and dense population), Paris,  Rome, and
Stockholm. (The publications  on respiratory diseases were reviewed in the 2004 PM AQCD). The
specific CVD outcomes  considered in each city were: cardiac diseases (ICD-9: 390-429), IHD
(410-413) and CBVDs (430-438). Routine registers in all cities provided daily data on
hospitalizations. Only emergency hospitalizations were considered, except in Milan, Paris, and
Rome where only general admissions data were available.
      Ambient PMi0 levels were available in all cities except Paris  (PMi3 used), and Milan  and
Rome (TSP used). Data on gaseous pollutants (NO2, SO2, CO, and O3) were also available in most
cities. Five of the eight cities provided data on black smoke (BS). The length of the available
time-series varied by city but generally spanned from the early to mid-1990s.
      Within each city, associations between cause-specific hospitalization rates and same-day PM2 5
levels were evaluated using Poisson GAMs controlling for long-term temporal trends and
meteorologic conditions. City-specific results were subsequently averaged using standard
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meta-analytic methods. The original analyses (Atkinson et al., 2001, 021959; Le  et al., 2002,
023746) were carried out using general additive models (GAM) and LOESS smoothers. Following
reports of problems associated with using the default convergence criteria in the standard S-plus
GAM procedure (Dominici et al., 2002, 030458). study authors reanalyzed the data on cardiac
admissions using GAMs and stricter convergence criteria,  and GLMs with natural splines and
penalized splines (Atkinson et al., 2003, 042797: Le et al., 2003, 042820). The authors found that
the results of the original analyses were insensitive to the choice of convergence criteria and that the
use of GLMs with penalized splines yielded very similar results.

      HEAPSS: Health Effects of Air Pollution among Susceptible Subpopulations

      HEAPSS investigators collected data on patients hospitalized for a first MI in five European
cities between 1992 and 2000. Patients were identified from MI registers in Augsburg and
Barcelona,  and from hospital discharge registers in Helsinki, Rome and Stockholm. Data on daily
levels of PMio, were measured at central monitoring sites in each city. Particle number concentration
was measured  for a year in each city and then modeled retrospectively  for the whole study period.
Associations of outcomes with gaseous criteria pollutants were also evaluated.
      Von Klot et al. (2005, 088070) identified 22,006 survivors of a first MI in the five participating
European cities and collected data on  subsequent first cardiac  re-hospitalizations between 1992 and
2001. Readmissions of interest were those with primary diagnoses of acute MI, angina pectoris, or
cardiac disease (which additionally includes dysrhythmias  and CHF). Within each city, associations
between cause-specific hospitalization rates  and same-day  levels of PMi0 were evaluated using
Poisson GAMs controlling for long-term temporal trends and  meteorologic conditions using
penalized splines. City-specific results were combined using standard meta-analytic methods.
Subsequently, Lanki et al. (2006, 089788) used HEAPSS data from 26,854 patients to evaluate the
association between daily PMio and particle number concentrations and the risk of hospitalization  for
first MI.

      PSAS: The French National Program on Air Pollution Health Effects

      Larrieu et al. (2007, 093031) evaluated the association between PM10 and the risk of
hospitalization in eight French cities between 1998 and 2003.  The cities examined were: Bordeaux,
Le Havre, Lille, Lyon, Marseille, Paris, Rouen and Toulouse. The specific CVD outcomes
considered  in each  city included:  total CVD  (ICD-10: 100-199), cardiac disease (100-152), IHD
(120-125) and stroke (160-164, G45-G46). The available data did not differentiate between emergency
and non-emergency hospitalizations. Daily mean PMio and NO2 levels  as well as 8-h max O3 levels
were obtained  from a network of monitors in each city.
      Within each city, associations between cause-specific hospitalization rates and 2-day ma (lag
0-1 days) levels of PMio were evaluated using Poisson GAMs controlling for long-term temporal
trends and meteorologic conditions using penalized splines. City-specific results were combined
using standard meta-analytic methods. Host  et al.  (2008, 155852) used a subset of these data (6
cities, 2000-2003) to compare the effects of PM2.5 and PMi0_2.5 on the risk of cardiovascular and
respiratory  admissions. CVD outcomes assessed in this analysis were all CVD (ICD-10 100-199),
cardiac disease (100-152) and IHD (120-125). PM2.5 levels were obtained from the same network of
background monitors described above. PMi0_2.s was calculated by subtracting PM2 5 levels from PMio
levels. Gaseous pollutants and hospital admissions for stroke were not  considered in this analysis.

      Multicity Studies in Australia and New Zealand

      Barnett et al. (2006, 089770) collected data on daily  CVD emergency hospital admissions
among older adults and pollution data between 1998 and 2001 in five Australian cities (Brisbane,
Canberra, Melbourne, Perth, Sydney)  and two cities in New Zealand (Auckland, Christchurch). In
2001, these cities covered 53% of the  Australian population and 44% of the New Zealand
population. The specific outcomes considered in each city  were: all circulatory diseases (ICD-9
390-429, ICD-10 100-199 with exclusions); CHF (ICD-9 428,  ICD-10 150); arrhythmia (ICD-9 427
ICD-10 146-49); cardiac disease (ICD-9 390-429, ICD-10 100-152,197.0, 197.1,198.1); IHD (ICD-9
410-413, ICD-10 120-24,125.2); acute MI (ICD-9 410, ICD-10 121-22); and stroke (ICD-9 430-438,
ICD-10 160-66,167,168,169, G45-46  with exclusions).
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      Air pollutants considered were 24-h avg PM10, 24-h avg PM2.5, BSP and gaseous pollutants.
Within each city, associations between cause-specific hospitalization rates and 2-day ma (lags
0-1 days) of PMio were evaluated using the time-stratified case-crossover approach which controls
for long-term and seasonal time trends by design rather than analytically. City-specific results were
combined using random effects meta-analytic methods.

      EMECAS: Spanish Multicentric Study on the Relation between Air Pollution and Health

      Ballester et al. (2006, 088746) collected data on daily cardiovascular emergency hospital
admission and air pollution data between approximately 1995 and 1999 in 14 cities in Spain. The
specific outcomes considered in each city were: total CVD (ICD-9: 390-459) and heart diseases
(410-414, 427, 428). Air pollutants considered were PMio, TSP, BS, SO2, NO2 (24-h avg), CO and
O3 (8-h max).
      Within each city, associations between cause-specific hospitalization rates and daily levels of
each pollutant metric were evaluated using Poisson GAMs with strict convergence criteria. In all
models, pollutants were entered as linear continuous variables and included control for confounding
by meteorological variables, influenza rates, long-term time trends, and unusual events. The authors
considered both distributed lag models (lags 0-3 days) and the 2-day ma of pollution (lags 0-1 days).
City-specific results were combined using standard meta-analytic methods.


6.2.10.1. All Cardiovascular Disease

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) incorporated the results of a large number of
time-series studies in the U.S. and elsewhere relating ambient PM levels and risk of hospitalization
for CVD. The 2004 PM AQCD (U.S. EPA, 2004, 056905) noted that the strongest evidence for this
association came from the NMMAPS study (Samet  et al., 2000, 010269) and the subsequent
reanalysis by Zanobetti and Schwartz (2003, 157174).
      Since then, the U.S. MCAPS study evaluated the association between PM2.5 and risk of CVD
hospitalization in 202 U.S. counties between 1999 and 2005 and found a 0.8% (95% posterior
interval (PI): 0.6-1.0) increase in risk per 10 (ig/m3 increase in PM25 on the same day (Bell  et al.,
2008, 156266: Peng et al., 2008, 156850). In 108 U.S. counties with co-located PMi0 and PMi0.2.5
monitors, Peng et al. found a 0.4% (95% PI, 0.1- 0.7, lag 0) increase in risk per 10  (ig/m3 PMi0_2.5
and no associations at lags of 1 and 2 days (Peng et al., 2008, 156850). In a two-pollutant model
adjusted for PM25, the association between PMi0_25 and CVD hospitalization lost precision (0.3%
[95% PI: -0.1 to 0.6, lag 0]). Bell et al. (2008, 156266) found evidence of substantial and
statistically significant variability in the effects of PM25 on cardiovascular hospitalizations by season
and region, with the highest national average estimates occurring in the winter and the highest
regional estimates in the northeastern U.S. (1.08% [95% PI: 0.79-1.37, lag 0, per 10 (ig/m3 increase
in PM2.5]). Estimates  for the nation (1.49% [95% PI:  1.09-1.89, lag 0]) and northeast (2.01% [95%
PI: 1.39-2.63, lag 0]) were highest in the winter.
      Bell et al. (2009, 191997) and Peng et al. (2009, 191998) used data from the MCAPS study
and the EPA's Speciation Trends Network (STN) to identify the components of PM2 5 that are most
strongly associated with hospitalizations for CVD. Peng et al. (2009, 191998) focused on the
components that make up the majority of PM25 mass (SO42~, NO3~, Si, EC, OC, Na+ and NH4+) and
found that in multipollutant models, only EC and OC were significantly associated with risk of
hospitalization for CVD. Bell et al. (2009, 191997) used data from 20 PM2 5 components and found
that EC, Ni, and V were most positively and significantly associated with the risk of cardiovascular
hospitalizations. These results suggest that the observed associations between PM2 5 and CVD
hospitalizations may be primarily due to particles from oil combustion and traffic.
      Additional evidence is provided  by several large multicity studies conducted outside of the
U.S. The European APHEA2 study (Le et al.,  2002,  023746) looked at admissions for CVD among
those aged >65 and found a 0.7% (95% CI: 0.4-1.0,  lag 0-1 day avg) increase in risk per 10 (ig/m3
PMio. The Spanish EMECAS study (Ballester  et al., 2006, 088746) looked at admissions for CVD
and found a 0.9% (95% CI: 0.4-1.5, lag 0-1 day avg) increase in risk per 10 (ig/m3  PMi0. The French
PSAS program looked at CVD hospitalizations among the elderly and found a 1.9% (95% CI:
0.9-3.0, lag 0-1 day avg) increase in risk with a 10 ug/m3 increase in PM25 and a 1.1% (95% CI: 0.5-
1.7) increase in risk with PM10 (Host et al., 2008, 155852; Larrieu  et al., 2007, 093031).
Non-significant increases in CVD hospital admissions association with PMi0_2.5 were reported (1.0%
December 2009                                  6-60

-------
[95% CI: -1.0 to 3.0]) (Host et al., 2008, 155852). In multiple cities across New Zealand and
Australia, Barnett et al. (2006, 089770) found a 1.3% (95% CI: 0.6-2.0, lag 0-1 day avg) increase in
risk per 10  (ig/m3 increase in PM25.
      The Atlanta-based SOPHIA study found a 3.3% (95% CI: 1.0-5.6, lag 0-2 day avg) and a 0.9%
(95% CI: -0.2 to 1.9, lag 0-2 day avg) increase in risk with a 10 (ig/m3 increase in PM2.5 and PMi0,
respectively (Metzger et al., 2004, 044222). In a more recent analysis from this study with an
additional four years of data, ED visits for CVD were not significantly associated with PM10 or
PM25, but were significantly associated with total carbon (1.6% [95% CI: 0.5-2.6, per IQR
increase]), EC (1.5% [95% CI: 0.5-2.5, per IQR increase]) and OC (1.5% [95% CI: 0.5-2.6, per IQR
increase]) components of PM25 (2007, 090316). A weak non-significant association PMi0_25 was
observed in these data (Tolbert  et al., 2007, 090316) More recently, Sarnat et al. (2008, 097972)
used multiple source-apportionment methods to evaluate the association between all CVD ED visits
and specific PM2 5 sources and found consistent positive associations with sources related to motor
vehicles and biomass combustion. These results were insensitive to the source-apportionment
technique used. It is noteworthy that other traffic-related gaseous pollutants were associated with
CVD ED visits in the SOPHIA study (Metzger et al., 2004, 044222).
      Using meta-regression techniques and the reported association between PMi0 and CVD
hospitalizations from the 14 cities included in the NMMAPS analysis, Janssen et al. (2002, 016743)
examined whether the between-city variability in relative risk estimates were related to the local
contribution of a number of PM sources. The authors found that in multivariate analyses PMi0
coefficients increased significantly with increasing percentage of PMi0 emissions from highway
vehicles/diesels and oil combustion.
      A small number of additional single-city studies have been published showing positive
associations between hospital admissions and ambient PM in Copenhagen, Denmark (Andersen et
al., 2007, 093201). weak nonsignificant associations in Spokane, WA (Schreuder et al., 2006,
097959; Slaughter et al., 2005,  073854), and no associations in two small counties in Idaho (Ulirsch
et al., 2007, 091332). Schreuder et al. (2006, 097959) performed a source apportionment analysis
using seven years of daily  speciation data from the same residential monitor in  Spokane, WA used by
Slaughter et al. (2005, 073854). These authors related daily levels of four sources (wood smoke, an
As-rich source, motor vehicle emissions, and airborne soil) to the excess risk of cardiovascular ED
visits. During the heating season, the only notable association for CVD-related ED visits was with
wood smoke, while in the non-heating season the only notable association was  with airborne soil.
While neither of these associations reached statistical significance, the study likely lacked the
statistical power to find effects of the expected magnitude. In fact, it is doubtful that studies
conducted outside of large metropolitan areas have sufficient statistical power to detect associations
of the expected magnitude. Delfino et al. (2009,  191994) evaluated the effects of the 2003 California
wildfires and observed a slightly larger excess risk of total CVD admissions during the wildfire
period compared to the period prior to the wildfire, although excess risk estimates were generally
weak and non-significant.
      Studies in  several cities in Australia have investigated the association of CVD admissions with
PM concentration and sources. A study from Sydney, Australia found a 1.8% (95% CI: 0.4-3.2) and
0.3% (95% CI: -0.8 to 1.4) excess risk per 10 (ig/m increase in the 2-day ma (lags 0-1 days) in
PM2.5 and PM10, respectively (Jalaludin et al., 2006, 189416).  Johnston et al. (2007, 155882) and
Hanigan et al. (2008, 156518) studied the association between PMio and cardiovascular and
respiratory  hospitalizations in Darwin, Australia, where the predominant source of PM is from
biomass combustion. The authors found little or no evidence of an  association between PMi0 and
CVD hospital admissions in the general population.
      Crustal material has also been investigated in an  effort to explain associations of PM
concentration with CVD admissions. Studies of a dust storm in the Gobi desert that transported PM
across the Pacific Ocean reaching the western U.S. in the spring of 1998 have been conducted. An
analysis of the health impacts of this event on the population of British Columbia's (Canada) Lower
Fraser Valley found no excess risk of cardiac or respiratory hospital admissions despite hourly PMi0
levels >100 (ig/m3 (Bennett et al., 2006, 088061). On the other hand, a number of studies in Asia
and eastern Europe have reported associations between CVD hospital admissions and dust storm
events. Middleton et al. (2008, 156760) found that dust storms in Cyprus were associated with a
4.7% (95% CI: 0.7-9.0) and 10.4% (95% CI: -4.7 to 27.9) increase in risk of hospitalization for all
causes and  CVD, respectively. Chan et al. (2008,  093297) studied the effects of Asian dust storms on
cardiovascular hospital admissions in Taipei, Taiwan and also found significant adverse effects
December 2009                                  6-61

-------
during 39 Asian dust events with high PM10 levels (daily PM10 >90 (ig/m3). Bell et al. (2008,
091268) analyzed these data independently and concluded that Asian dust storms were positively
associated with risk of hospitalization for IHD.
Study
Bell etal. (2008,156266)
Hostetal. (2008, 155852)
Barnett etal. (2006. 089770)
Metzger et al. (2004, 044222)
Tolbert etal. (2007,090316)
Slaughter etal. (2005. 073854)
Delfino etal. (2009, 191994)
Location
202 Counties, US
6 Cities, France
7 Cities, Australia/NZ
Atlanta, GA
Atlanta, GA
Spokane, WA
CA
Lag
0
0
0
0
0-1
0-1
0-2
0-2
1
0-1
Covariates Effect Estimate (95% Cl)
65+ Overall
65+ NE
65+, Winter
65+ NE Winter
65+
65+
All Ages
All Ages _
All Ages
*. PM2.5
-*-
U —
All Ages, Wildfires J_i —

Peng etal. (2008. 156850)
Hostetal. (2008, 155852)
Tolbert etal. (2007, 09031 6)
108 Counties, US
6 Cities, France
Atlanta, GA
0
1
2
0-1
0-2
65+ [*- PMio-2.5
65+ -f
65+ -•-
All Ages 	

Zanobetti & Schwartz (2003, 043119)
Metzger et al. (2004, 044222)
Tolbert etal. (2007. 09031 6)
Ballester etal. (2006, 088746)
Ulirsch etal. (2007.091332)
Slaughter et al. (2005, 073854)
LeTertre etal. (2002, 023746)
10 Cities, US
Atlanta, GA
Atlanta, GA
14 Cities, Spain
Pocatello, Chubbuck, ID
Spokane, WA
8 Cities, Europe
0-1
0-2
0-2
0-1
0
1
0-1
65+
All ages
All Ages
65+
	 •

1 * PMio
.T
50-r « 1
All dgeb 	 *
65+
+
iii iii
-0-4-20 2 4 6
                                                         Excess Risk Estimate

Figure 6-1.    Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.s, PMio. 2.5, and
              concentration for CVD ED visits and HAs. Studies represented in the
              figure include all multicity studies, as well as single-city studies conducted in the
              U.S. or Canada.

      The effect estimates from multicity studies and single-city studies conducted in the U.S. and
Canada are included in Figure 6-1. Information on PM concentrations during the relevant study
period is presented in Table 6-8. In summary, large studies from the U.S., Europe, and Australia/New
Zealand published since the 2004 PM AQCD (U.S. EPA, 2004, 056905) provide support for an
association between short-term increases in ambient levels of PM2.5 and PMio and increased risk of
hospitalization for total CVD. The evidence for an association of CVD hospitalization with PMi0_2.5
is relatively limited. Peng et al. (2008, 156850) reported that their PM10_2.5 estimate was not robust to
adjustment for PM2.5 and estimates from the other studies are imprecise. The average excess risk
among the U.S. elderly is likely in the range of 0.5-1.0% per 10 (ig/m3 increase in PM25, although
substantial variability by region of the country and season has been demonstrated. An excess risk of
ED visits for CVD of a similar magnitude appears  likely. The excess risk of CVD hospitalization
may be somewhat greater in Europe and Australia/New Zealand than in the U.S. Sources including
wood burning, oil burning, traffic and crustal material have been associated with increases in
cardiovascular hospitalization or ED visits, but the best evidence suggests that in the U.S., oil
combustion, wood burning, and traffic are likely the sources of PM25 most strongly associated with
cardiovascular hospitalizations or ED visits.
December 2009
6-62

-------
Table 6-8. Characterization of ambient
admission and ED visits for
Pollutant
Study
PM concentrations in epidemiologic studies of hospital
cardiovascular diseases.
Location
Mean Concentration
(ug/m3)
Upper Percentlle
Concentration (ug/m3)
PM2.5
















Barnett et al. (2006, 089770)
Bell et al. (2008, 1562661
Burnett etal. (1999, 017269)
Dominic! et al. (2006, 088398)
Delfino et al. (2009, 191994)
Host et al. (2008, 1558521
Ito et al. (2003, 0428561: Lippman (2000, 0119381
Lisabeth et al. (2008, 1559391
Metzger etal. (2004,044222)
Pope et al. (2006, 0912461
Slaughter etal. (2005, 0738541
Sullivan et al. (2005, 0508541
Symons et al. (2006, 091258)
Tolbertetal. (2007, 090316)
Villenueve et al. (2006, 0901911
Zanobetti and Schwartz (2005, 0880691
7 cities in Australia
202 counties in the U.S.
Toronto Canada
204 counties in the U.S.
6 counties CA
6 cities in France
Detroit, Ml

Atlanta, GA
Wasatch Front, Utah
Spokane, WA
King County, WA
Baltimore, MD
Atlanta, GA
Edmonton, Canada
Boston, MA
8.1-11.0
12.92
18
13.4
18.4-32.7
13.8-18.8
18
7
17.8
10.1-11.3
NR
12.8
16
17.1
8.5
11.1 (median)
NR
34.16
95th: 34.0, Max: 90
NR
45.3-76.1 (wildfire period)
95th: 25-33
98th: 55.2
75th: 10
90th: 32.3
98th: 39.8
Max: 82-1 44
90th: 20.2
90th 27.3, Max: 147
Max: 69.2
98th: 38.7
75th: 11
95th: 26.31
98th: 55.2
PM10-2.5









Burnett etal. (1999, 0172691
Host et al. (2008, 1558521
Ito et al. (2003, 042856): Lippman (2000, 011938)
Le Tertre et al. (2002, 023746)
Metzger etal. (2004, 0442221
Peng et al. (2008, 1568501
Peters etal. (2001,0165461
Slaughter etal. (2005, 073854)
Tolbertetal. (2007, 090316)
Toronto, Canada
6 cities in France
Detroit, Ml
8 cities in Europe
Atlanta, GA
204 cities in the U.S.
Boston, MA
Spokane, WA
Atlanta, GA
12.2
7-11
13
NR
9.1
9.8 (Median)
7.4
NR
9
Max: 68
95th: 12.5-21.0
Max: 50
NR
90th: 16.2
75th: 15.0
95th: 15.2
NR
Max: 50.3
PM10







Ballester et al. (2006, 088746)
Barnett et al. (2006, 0897701
Burnett et al. (1999, 0172691
Ito et al. (2003, 042856): Lippman (2000, 011938)
Jalaludin et al. (2006, 1894161
Larrieu et al. (2007, 093031)
Le Tertre et al. (2002, 023746)
14 cities in Spain
7 cities in Australia and New
Zealand
Toronto, Canada
Detroit, Ml
Sydney, Australia
8 cities in France
8 cities in Europe
32.8-43.2
16.5-20.6
30.2
31
16.8
21.0-28.9
Range: 15.5-55.7
90th: 50.3-62.6
NR
95th: 56.0
NR
75th: 19.9
Max: 103.9
NR
Range 75th: 19. 9-66
December 2009
6-63

-------
Pollutant Study
Linn et al. (2000, 0028391
Metzgeretal. (2004, 044222)
Morris etal. (1998, 0249241
Peters etal. (2001,0165461
Schwartz et al. (1995, 0461861
Slaughter etal. (2005, 073854)
Tolbertetal. (2007, 090316)
Ulirsch et al. (2007, 0913321*
Wfellenius et al. (2005, 0874831
Wfellenius et al. (2005, 0886851
Wfellenius et al. (2006, 088748)
Zanobetti and Schwartz (2005, 088069)
Location
Los Angeles, California
Atlanta, GA
Chicago, Illinois
Boston, MA
Detroit, Ml
Spokane, WA
Atlanta, GA
2 cities in southeast Idaho
Pittsburgh, PA
9 cities in the U.S.
7 cities in the U.S.
Boston, MA
Mean Concentration
(ug/m3)
45
26.3
41
19.4
48
NR
26.6
24.2/23.2
31.1
28.4 (median)
28.3 (median)
28.4 (median)
Upper Percentlle
Concentration (ug/m3)
78 (summer) -132 (fall)
90th: 44.7
75th: 51
Max: 117
95th: 37.0
90th: 82
90th: 41. 9
Max: 98.4
90th: 40.7/37.4
95th: 70.5
90th: 57.9
90th: 57
90th: 53.6
*Results presented separately for 2 separate time series
6.2.10.2.  Cardiac Diseases

      Cardiac disease represents a subset of CVD which specifically excludes hospitalizations for
CBVD, peripheral vascular disease, and other circulatory diseases not involving the heart or
coronary circulation. Only a small number of studies published since the 2004 PM AQCD
(U.S. EPA, 2004, 056905) have evaluated the association between ambient PM and hospitalizations
for cardiac diseases, as most investigators have focused instead on more narrowly defined outcomes.
      The French PSAS program found a 2.4% (95% CI: 1.2-3.7, lag 0-1) and 1.5% (95% CI:
0.5-2.2, lag 0-1) excess risk among the elderly per 10 (ig/m3 increase in PM25 and PMi0,
respectively (Host et al., 2007,  155851: Larrieu et al., 2007, 093031). Host et al. (2008, 155852)
also found a positive less precise association with PMi0_2.5, (excess relative risk per 10 ug/m3: 1.6%
[95% CI: -0.8 to 4.1]). The European HEAPSS study looked at cardiac readmissions among
survivors of a first MI and found a 2.1% (95% CI:  0.4-3.9, lag 0) excess risk per 10 (ig/m3 increase
in PM10 (Von et al., 2005, 088070). A 1.9% (95% CI: 1.0-2.7, lag 0-1) excess risk per 10 ug/m3
increase in PM2.5 was observed in several cities in Australia and New Zealand (Barnett et al., 2006,
089770). Single-city studies of hospital admissions from Kaohsiung and Taipei, Taiwan, and an ED
visit study from Sydney, Australia also reported statistically significant positive associations(Chang
et al., 2005, 080086: Jalaludin  et al., 2006, 189416: Yang et al., 2004, 094376). On the other hand,
Slaughter et al.  (2005, 073854) found no association between either PM2.5 or PMi0 and risk of
cardiac hospitalization in Spokane, Washington.
      In summary, although relatively few studies have focused on all cardiac diseases, large studies
from Europe and Australia/New Zealand published since the 2004 PM AQCD (U.S. EPA, 2004,
056905) report positive associations between short-term increases in ambient levels of PM2.5,
PM10_2.5, and PM10and increased risk of hospitalization for cardiac disease. The results from small
single-city studies are less consistent. The excess risk for cardiac hospitalizations may be somewhat
larger than for total CVD hospitalizations.


6.2.10.3.  Ischemic Heart Disease

      IHD represents a subset of all cardiac disease hospitalizations and typically includes acute MI
(ICD 9: 410), other acute and subacute forms of IHD (411), old MI (412), angina pectoris (413), and
other forms of chronic IHD (414). Some authors term this category coronary heart disease. Published
studies evaluating IHD as a single outcome are considered first, followed by consideration of studies
looking at acute MI, a specific form of IHD.
      In one of the first studies to evaluate IHD, Schwartz and Morris (1995, 046186) reported a
0.6% (95% CI:  0.2-1.0) excess risk of hospitalization for IHD per 10 (ig/m3 increase in mean PMi0
December 2009
6-64

-------
levels over the previous two days among elderly Medicare beneficiaries living in Detroit between
1986 and 1989. As reviewed in the 2004 PM AQCD (U.S. EPA, 2004, 056905). similar associations
were subsequently observed in many single-city studies including: London, England (Atkinson et
al., 1999, 007882). Toronto, Canada (Burnett et al., 1999, 017269). and Seoul, Korea (Lee et al.,
2003, 095552). Studies in Hong Kong (Wong et al., 1999, 009172: Wong et al., 2002, 023232).
Birmingham, England (Anderson et al., 2001, 017033). and London, England (Wong et al., 2002,
023232) yielded positive point estimates of a similar magnitude, but did not reach statistical
significance.
      The positive associations between short-term changes in PM and IHD hospitalizations
observed in the early single-city studies have been confirmed in several large multicity studies. The
U.S. MCAPS study (Dominici et al., 2006, 088398) found a 0.4% (95% CI: 0.0-0.8) excess risk of
hospitalization for IHD per 10 ug/m increase in PM25 two days earlier. The European APHEA-2
study (Le et al., 2002, 023746) considered PM10 and found a 0.8% (95% CI: 0.3-1.2, lag 0-1) excess
risk among those aged >65 yr. Among the elderly in 5 cities in Australia and New Zealand (Barnett
et al., 2006, 089770) there was a 4.3% (95% CI: 1.9-6.4, lag 0-1) excess risk per 10 ug/m3 increase
in PM25. Among the elderly in several French cities there was a 4.5% (95% CI: 2.3-6.8, lag 0-1),
6.4% (95% CI:  1.6-11.4, lag 0-1) and 2.9% (95% CI: 1.5-4.3, lag 0-1) excess risk per 10 ug/m3
increase in PM25  PMi0_25 (Host et al., 2008, 155852). and PMi0, respectively (Larrieu et al., 2007,
093031).
      With regard to ED visits, the Atlanta-based SOPHIA study  (Metzger et al., 2004, 044222)
found positive associations with PM25 and PMi0 (ranging from 1.1 to 2.3%), but the effect estimates
did not reach statistical significance. Similarly, associations of EC and OC with IHD were increased
but not significant. In 6 cities across Canada, Szyszkowicz (2009, 191996) observed a 2.4% (95%
CI: 1.2-3.6) and 1.4% (95% CI: 0.7-2.0) excess risk of ED visits for angina per 10 ug/m3 increase in
same-day PM25 and PM10, respectively. Although excess risks were generally weak and non-
significant, Delfmo et al. (2009, 191994) observed  a slightly larger excess risk of IHD during
wildfires compared to the pre-wildfire period. In Sydney, Australia, Jalaludin et al.  (2006, 189416)
found a 2.6% (95% CI: 0.1-5.2) and 0.8% (95% CI: -1.2 to 2.8) excess risk of ED visits for IHD per
10 ug/m3 increase in 2-day ma of PM25 and PMi0, respectively. A recent study in Helsinki, Finland,
found no evidence of an association of IHD hospital admissions with UFP, ACP, PM25, PMi0_25, or
source-specific PM2.5 (Halonen et al., 2009, 180379).
      To explore this link further, Pope et al. (2006, 091246) used data from an ongoing registry of
patients undergoing coronary angiography at a single referral center in Salt Lake City, UT, between
1994-2004. The authors found a 4.8% (95% CI: 1.0-8.8, lag 0) excess risk of acute MI or unstable
angina per  10 ug/m3 increase in PM25 among 4,818 patients. These results were robust to changes in
the definition of the outcome. The results of this study are particularly noteworthy given the high
specificity of the outcome definition.
      In  summary, large studies from the U.S., Europe, and Australia/New Zealand published since
the 2004 PM AQCD (U.S.  EPA, 2004, 056905) provide support for an association between
short-term increases in ambient levels of PMi0 and  PM25 and increased risk of hospitalization or ED
visits for ischemic heart diseases. Although estimates are less precise for PMi0_2.5, most results from
single pollutant models provide evidence of a positive association between PMi0_2.5 and IHD.
Moreover, Host et al. (2008, 155852) found that the effect estimates for the association of PM25 and
PMio_2.5 with IHD were very similar when scaled to the IQR of each metric. Estimates of the excess
risk vary considerably between studies, but as was the case for total CVD hospitalizations, the excess
risk appears to somewhat greater in Europe and Australia/New Zealand. Results from multicity
studies and U.S. and Canadian single-city studies are presented in Figure 6-2.
December 2009                                 6-65

-------
Study
         Location
Lag   Age
Effect Estimate (95% Cl)
ISCHEMIC HEART DISEASE
Ito (2003, 042856)
Popeetal (2006 091246)
Hostetal. (2007, 155851)
Metzgeretal (2004 044222)*
Barnettetal (2006 089770)
Dominici et al. (2006, 088398)
Barnettetal. (2006.089770)
Hostetal. (2007. 155851)
Burnett etal. (1999. 01 7269)
Delfinoetal. (2009. 191994)

Mpt7npr pt ai or\r\A 044999^


Burnett etal. (1999. 01 7269)
Ito (2003. 042856)
Le Tertre et al. (2002, 023746)
Metzger et al. (2004, 044222)*
Larrieu etal. (2007. 09X31)
Burnett etal. (1999.017269)
Le Tertre etal. (2002. 023746)
Jalaludin etal. (2006. 189416)*
Larrieu etal. (2007, 09X31)
MYOCARDIAL INFARCTION
Peters etal (2001 016546)

Sullivan et al (2005 050854)



Zanobetti & Schwartz (2006, 090195)
pptprcptai nnm mfi^di^

Linn etal. (2000.002839)

Zanobetti & Schwartz (2005, 088069)
Detroit, Ml
Utah Valley UT
6 Cities, France
Atlanta GA
Australia/NZ
204 Counties, US
Australia/NZ
6 Cities, France
Toronto, Can
6 Counties, CA
(Wildfires)

Atlanta flA


Toronto, Can
Detroit, Ml
8 Cities, Europe
Atlanta, GA
8 Cities, France
Toronto, Can
8 Cities, Europe
Sydney, Australia
8 Cities, France
Boston MA

King County WA



Boston, MA


Los Angeles, CA

21 Cities, US
1
o
0-1
0-3
0-1
0
1
2
0-2 DL
0-1
0-1
0,1
0,1

n ?


0
1
0-1
0-2
0-1
0-1
0-1
0-1
0-1
2h
24 h
1 h
2h
4h
24 h
0
9 h
94 h
0
9 h
94 h
0
65+ -
All
All J
All
15-64
65+
65+ i
65+
65+ n
65+
65+
All
All -

All f •


All
65+
<65
All
All
All
65+
65+ —i
65+
61 6 Mean
61 6 Mean
21-98
9 1-98
0 1-98
9 1-98
65+
R1 R Mmnf

>x
fi1 fi Mpan
R1 R Mpan
65+
-. 	 PM2.5
1 — • —

t-
•-
»-
•-
-• —



*
-•-
-t— PMio
••
-• —
-•-
h-» 	
PM2.5

*
*
_
*
	 • 	
PMlO-2.5

^ PMio
*
•»
                                                 i  r
                                                -6
                                          o
                      n  i   r
                            6
                                                                                 \  r
                    12
18
~  i   i
24   28
  * ED Visits
 DL Distributed Lag


Figure 6-2.
                                  Excess Risk (%)
Excess risk estimates per 10 ug/m  increase in 24-h avg (unless otherwise noted)
PM2.6, PMio-2.5, and PMio concentration for Ml and IHD ED visits and HAs. Studies
represented in the figure include all multi-city studies as well as single-city
studies conducted in U.S. or Canada.
December 2009
                               6-66

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6.2.10.4.  Acute Myocardial Infarction

      Because even IHD refers to a heterogeneous collection of diseases and syndromes, several
authors have evaluated the association between short-term fluctuations in ambient PM and acute MI,
a specific form of IHD.
      In 2001, Peters et al. (2001, 016546) published their study evaluating the effects of PM on the
risk of MI among 772 Boston-area participants in the Determinants of MI Onset Study. The authors
found that a 10 ug/m3 increase in the 2-h or 24-h avg levels of PM25 was associated with a 17%
(95% CI: 4-32) and 27% (95% CI: 6-53) excess risk of MI, respectively. An imprecise, non-
significant association between PMi0_2.5 and onset of MI was observed in Boston. In contrast, a study
among 5793 patients in King County, WAthat used similar methods, found no association with PM25
with lag times of 1, 2, 4, or 24 h (Sullivan et al., 2005, 050854). Among 852 hospitalized patients in
Augsburg, Germany, Peters et al. (2005, 087759) also found no association between PM2 5 and MI
risk within this time frame, although they did find a positive and statistically significant association
with time spent in traffic (Peters  et al., 2004, 087464).
      These three studies are particularly important because in each one: (1) cases were
prospectively identified based on clinical criteria rather than retrospectively based on discharge
diagnoses; and (2) time of MI symptom onset was used for exposure assessment rather than date of
hospital admission. Whether the discrepant results among these studies are  due to regional
differences in population characteristics and/or air pollution sources remains unclear. The King
County study suggests that differences in statistical approaches are unlikely to account for the
discrepant results (Sullivan et al., 2005, 050854). Analyses from the U.S. MCAPS study suggest
that substantial heterogeneity of effects are to be expected  across regions of the country (Bell et al.,
2008, 156266)
      Several studies have assessed the association between acute exposure to ambient PM and  MI
using administrative databases. In the U.S., MI was not one of the specific endpoints evaluated in the
MCAPS study (Dominici  et al., 2006, 088398) or in the Atlanta-based SOPHIA study of ED visits
(Metzger  et al., 2004, 044222). However, Zanobetti and Schwartz (2005, 088069) found a 0.7%
(95% CI: 0.3-1.0) excess risk of MI per 10  ug/m3 increase in same-day PM10 among elderly
Medicare beneficiaries in 21 cities. Subsequently, the same authors found that among elderly
Medicare beneficiaries living in the Boston metropolitan region, a 10 ug/m3 increase in PM25 was
associated with a 4.9% (95% CI:  1.1-8.2) excess risk on the same day (Zanobetti and Schwartz,
2006, 090195).
      This body  of evidence may implicate traffic-related pollution generally as a risk factor for MI.
In the study described above, Peters et al. (2001, 016546) found positive associations between risk of
hospitalization for MI and potential markers of traffic-related pollution measured at a central monitor
including BC, CO and NO2. However, none of these associations were statistically significant in
models adjusting for season, meteorological variables, and day of week. Zanobetti and Schwartz
(2006, 090195) examined the association between traffic-related pollution and risk of hospitalization
for MI among Medicare beneficiaries in the Boston area and found that  MI risk was positively and
significantly associated with measures of PM2 5, BC, NO2,  and CO, but not with levels of
non-traffic-related PM25. Peters et al. (2004, 087464) interviewed  691 subjects with MI who
survived at least  24-h  after the event and found a strong positive association between self-reported
exposure to traffic and the onset of MI within 1 h (OR: 2.9 [95% CI: 2.2-3.8]). The association was
somewhat stronger among subjects traveling by bicycle or public transportation in the hour prior to
the event.  Of note, however, this study did not directly measure traffic-related pollution.
      Similar studies with administrative databases have been conducted in Europe, Australia, and
New Zealand. Barnett et al. (2006, 089770) observed that in five cities in Australia and New
Zealand, a 10 ug/m3 increase in PM25 was associated with a 7.3%  (95% CI: 3.5-11.4, lag 0-1 day)
excess risk. In Rome,  D'Ippoliti et al. (2003, 074311) carried out a case-crossover study and found a
statistically significant positive association between TSP and the risk of hospitalization for MI. In
contrast, the HEAPSS study found no evidence of an association between PMi0 and risk of
hospitalization for a first MI in five European cities (Lanki  et al., 2006, 089788). although there is
some indication that among survivors of a first MI, risk of re-hospitalization for MI may be related
to transient elevations in PMi0 (Von  et al., 2005, 088070).
      In summary, large studies from the U.S., Europe, and Australia/New Zealand published since
the 2004 PM AQCD (U.S. EPA, 2004, 056905) provide support for an association between
short-term increases in ambient levels of PM25 and PMi0and increased risk of hospitalization for MI.
Some of the heterogeneity of results is likely explained by  regional differences in pollution sources,
December 2009                                  6-67

-------
components, and measurement error. One study of the effect of 2- and 24-h avg PM10_2.5
concentration on admissions for MI produced effect estimates that were positive, but imprecise
(Peters et al., 2001, 016546). These results need to be interpreted together with those studies
evaluating hospitalization for IHD since Mis make up the majority of hospitalizations for IHD. U.S.
studies of MI are included in Figure 6-2.


6.2.10.5.  Congestive Heart Failure

      Perhaps the first suggestion of an association between ambient PM and hospitalization for
CHF was provided by the study of Schwartz and Morris (1995, 046186). These authors reported that
among elderly Medicare beneficiaries living in Detroit between 1986-1989, a 10  ug/m3 increase in
mean PM10 levels over the previous two days was associated with a 1.0% (95% CI: 0.4-1.6) increase
in risk of hospitalization for CHF. As reviewed in the 2004 PM AQCD (U.S. EPA, 2004,  056905).
using similar approaches, statistically significant positive associations with PM2.5 or PMi0 were
subsequently reported in single-city studies looking at hospitalizations for CHF in Toronto (Burnett
et al., 1999, 017269). Hong Kong (Wong et al., 1999, 009172). and Detroit (Ito,  2003, 042856). but
not Los Angeles (Linn et al., 2000, 002839) or Denver (Koken et al., 2003,  049466). Burnett et al.
(1999, 017269) reports a significantly increased risk of CHF hospitalization with PM10_25 while
Metzger et al. (2004, 044222) and Ito et al.  found (2003, 042856) less precise associations.
      Subsequent multicity  studies support the presence of a positive association between PM
concentration and CHF hospitalization. In the U.S., the MCAPS study found a  1.3% (95%: 0.8-1.8)
excess risk per 10 ug/m3 increase in same-day PM25 (Dominici et al., 2006,  088398). In  addition,
Wellenius et al.  (2006, 088748) reported a 0.7% (95% CI: 0.4-1.1) excess risk of hospitalization for
CHF per 10 ug/m3 increase in same-day PM10 among elderly Medicare beneficiaries in seven cities.
In Australia and New Zealand, Barnett et al. (2006, 089770) found a 9.8% (95% CI: 4.8-14.8, lag 0-1
day) and 4.6% (95% CI:  2.8-6.3, lag 0-1 days) excess risk of hospitalization for CHF associated with
a 10 ug/m3 increase in PM25 and PMi0, respectively. Results from more recent  single-city studies in
Pittsburgh (Wellenius et al., 2005, 087483). Utah's Wasatch Front (Pope et al., 2008, 191969).
Kaohsiung, Taiwan (Lee et al., 2007, 093271) and Taipei, Taiwan (Yang, 2008, 157160)  have also
reported positive associations between PM  and CHF hospital admissions. In  addition, Yang et al.
(2009, 190341) found that hospitalizations for CHF were elevated during or immediately following
54 Asian dust storm events (while single day lags 0-3 were evaluated, maximum  excess risk
occurred at lag 1:  11.4% [95% CI: -0.7 to 25.0]). Delfino et al. (2009, 191994)  observed a slightly
larger excess risk of total CHF  during wildfires occurring in California compared to the period
before the wildfires.
      While most studies suggest an association at very short lags (0-1 days), the study by Pope
et al. (2008,  191969) failed to find such short term associations and instead suggested that PM2 5
levels averaged over the  past 2-3 wk may be more important. Pope et al. (2008, 191969)  observed a
13.1% (95% CI: 1.3-26.2) increase in CHF  hospitalization per 10 ug/m3 increase in PM25 (imputed
values used in analysis).  Whether findings at longer lags in this population represent true cumulative
effects of PM or are due to misclassification of symptom onset times remains to be determined.
      Findings from the Atlanta-based SOPHIA study (Metzger  et al., 2004, 044222) also support
the presence of a positive association between PM and CHF ED visits. Specifically, the SOPHIA
study found a 5.5% (95% CI: 0.6-10.5, lag 0-2 days) excess risk of ED visits for CHF per 10 ug/m3
increase in the 3-day ma of PM25. Positive  associations were also observed for CHF and  EC and OC
components of PM25. No associations were observed with PMi0and a weak, imprecise increase was
observed in association with PMi0_2.5.
      Only one published study has attempted to evaluate the effects of ambient particles on CHF
symptom exacerbation using data which was not derived from administrative databases. Symons
et al. (2006, 091258) interviewed 135 patients with prevalent CHF hospitalized for symptom
exacerbation in Baltimore, MD. The authors found a 7.4% (95% CI: -7.5 to 24.2) excess  risk of
hospitalization per 10 ug/m3 increase in PM25 two days prior to symptom onset. This finding did not
reach statistical significance and may be attributable to the lack of statistical  power needed to find an
effect of the expected magnitude.
      In summary, large  studies from the U.S., Europe, and Australia/New Zealand published since
the 2004 PM AQCD (U.S. EPA, 2004, 056905) provide support for an association between
short-term increases in ambient levels of PM25 and PMi0 and increased risk of  hospitalization and
ED visits for CHF. Although the number of studies is fewer (and only Metzger  et al., 2004,  044222
December 2009                                 6-68

-------
is new since the 2005 AQCD), elevated risks of hospitalization or ED visits for CHF in association
with PMio_2.5 have been observed. The excess risks associated with CHF hospitalizations and ED
visits are consistently greater than those observed for other CVD endpoints. The results of multicity
studies and U.S. and Canadian single-city studies are summarized in Figure 6-3.
Study
Burnett etal. (1999.017269)
Ito (2003, 042856)
Metzger et al. (2004, 044222)*
Barnett etal. (2006.089770)
Symons et al. (2006, 091258)
Dominici et al. (2006, 088398)
Barnett etal. (2006.089770)
Delfino etal. (2009. 191994)
Pope etal. (2008, 191969)
Burnett etal. (1999.017269)
Ito (2003, 042856)
Metzger et al. (2004, 044222)*
Burnett etal. (1999.017269)
Linn etal. (2000,002839)
Ito etal. (2003.042856)
Metzger et al. (2004, 044222)*
Barnett etal. (2006. 089770)
Schwartz & Morris (1995, 046186)
Morris & Naumova (1998, 086857)
Wellenius etal. (2005. 087483)
Wellenius etal. (2006. 088748)
Barnett etal. (2006.089770)
Location
Toronto, Canada
Detroit, Ml
Atlanta, GA
Australia/NZ
Baltimore, MD
204 U.S counties
Australia/NZ
CA wildfires
Utah
Toronto, Canada
Detroit, Ml
Atlanta, GA
Toronto, Canada
Los Angeles, CA
Detroit, Ml
Atlanta, GA
Australia/NZ
Detroit, Ml
Chicago, IL
Pittsburgh, PA
7 Cities, U.S.
Australia/NZ
Lag
0-2
1
0-2
0-1
2
0
0-1
0-1
14dDL
0-2
0
0-2
0-2
0
0
0-2
0-1
0-1
0
0
0
0-1
Age Effect Estimate (95% Cl)
All Ages
65+
All Ages
1c; GA
AIIAg°s 	
65+"
65+
All Anno
All Ages
All Ages
R^I
All Anr-
AIIAges
>30
65+

1^ R4
65+
65+
65+
65+
65+
1 1 i 1 I
	 * 	 PM2.5









— *— PMio
-•-


-»

I I I i I I I I
                                         -8  -6   -4-20
                                                        6   8
  * ED Visits
Figure 6-3.
                                                    Excess Risk Estimate
Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.6, PMi0.2.5, and
concentration for CHF ED visits and HAs. Studies represented in the
figure include all multicity studies as well as single-city studies conducted in the
U.S. and Canada.
6.2.10.6.  Cardiac Arrhythmias

      A number of studies based on administrative databases have sought to evaluate the association
between short-term fluctuations in ambient PM levels and the risk of hospitalization for cardiac
arrhythmias (also known as dysrhythmias). Typically in these studies a primary discharge diagnosis
of ICD-9 427 has been used to identify hospitalized patients. However, ICD-9 427 includes a
heterogeneous group of arrhythmias including paroxysmal ventricular or supraventricular
tachycardia, atrial fibrillation and flutter, ventricular fibrillation and flutter, cardiac arrest, premature
beats, and sinoarterial node dysfunction. One study in the Netherlands found that the positive
predictive value of ICD-9 codes related to ventricular arrhythmias and sudden cardiac death was
82% (De et al., 2005, 155746). The positive predictive value of other codes related to cardiac
arrhythmias is unknown, but likely to be lower.
      The results from early studies of arrhythmia-related hospitalizations have been inconsistent,
with positive findings in Toronto (Burnett et al., 1999, 017269) and null findings in Detroit
(Schwartz  and Morris, 1995, 046186). Los Angeles (Linn et al., 2000, 002839). and Denver (Koken
et al., 2003, 049466). The U.S. MCAPS study found a statistically significant 0.6% (95% CI:
0.0-1.2) excess risk of hospitalization for the combined outcome of cardiac arrhythmias and
conduction disorders (ICD-9: 426, 427) per 10 (ig/m3 increase in same-day PM2.5 (Dominici  et al.,
2006, 088398). A multicity study in Australia and New Zealand found no evidence of an association
between arrhythmia hospitalizations and either PM2.5 or PMio (Barnett et al., 2006, 089770). A study
in Helsinki, Finland, found no evidence of an association between either PM2.s or PMi0_2.5 and risk of
hospitalization for arrhythmias (Halonen et al., 2009, 180379). although there was an association
with smaller particles  (0.03-0.1 (im).
December 2009
                               6-69

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      With regard to ED visits, the Atlanta-based SOPHIA study found no evidence of an
association between any measure of ambient PM and the rate of ED visits for cardiac arrhythmias
(Metzger  et al, 2004, 044222). However, in Sao Paulo, Brazil, Santos et al. (2008, 192004) found a
3.0% (95% CI: 0.5-5.4) excess risk of ED visits for arrhythmias per 10 ug/m increase in PMio on
the same day.
      In summary, the current evidence does not support the presence of a consistent association
between short-term increases in ambient levels of PM25, PM10_2.5, or PM10and increased risk of
hospitalization for cardiac arrhythmias. However, it should be noted that studies of hospital
admissions or ED visits are ill-suited to the study of cardiac arrhythmias since most arrhythmias do
not lead to hospitalization. Studies in patients with implanted defibrillators, human panel studies
with ambulatory ECG recordings, and animal toxicological studies provide a more appropriate
setting for evaluating this endpoint. Results of these studies are described in Section 6.2.2.


6.2.10.7.  Cerebrovascular Disease

      Time-series studies evaluating the hypothesis that short-term increases in ambient PM2.5 or
PMio levels are associated with increased risk of hospitalization for CBVD have been inconsistent,
with few studies reporting positive associations (Chan  et al., 2006, 090193; Dominici et al., 2006,
088398; Metzger  et al., 2004, 044222; Wordley et al., 1997, 082745). and several studies reporting
null or negative associations (Anderson et al., 2001, 017033; Barnett et al., 2006, 089770; Burnett
et al., 1999, 017269; Halonen et al., 2009, 180379; Jalaludin  et al., 2006, 189416; Larrieu et al.,
2007, 093031; Le et al., 2002, 023746; Peel et al., 2007, 090442; Villeneuve et al., 2006, 090191;
Wong et al.,  1999, 009172).
      The U.S. MCAPS study found a 0.8% (95% CI: 0.3-1.4) excess risk of hospitalization for
CBVD per 10 ug/m3 increase in same-day PM25 (Dominici et al., 2006, 088398). The association
showed regional variability with the strongest associations  observed in the eastern U.S. The
Atlanta-based SOPHIA study found a 5.0% (95% CI: 0.8-9.3, lag 0-2 days) excess risk of ED visits
for cerebrovascular and peripheral vascular disease combined (excluding hemorrhagic strokes) per
                                                                                     10
10 ug/nf increase in PM2 5 and a 2.0% (95% CI: -0.1 to 4.3, lag 0-2 days) excess risk for PM
(Metzger  et al., 2004, 044222). Delfino et al. (2009,  191994) observed a weak association between
excess risk of CBVD admissions before and during a wildfire occurring in California and slightly
higher risks after the wildfire period.
      Large multicity studies conducted outside of North America have failed to observe an
association between PM and CBVD hospitalizations. The APHEA study found no excess risk (0.0%
[95% CI: -0.3 to 0.3]) of hospitalization for CBVD per 10 ug/m3 increase in the 2-day ma of PMio in
8 European cities (Le  et al., 2002, 023746). Investigators from the French PSAS program reported a
0.8% (95% CI: -0.9 to 2.5, lag 0-1 days) excess risk per 10 ug/m3 increase in PMio among patients
aged >65 yr and a 0.2% (95% CI: -1.6 to 1.9, lag 0-1  days) excess risk among all patients (Larrieu et
al., 2007, 093031). Although neither estimate was statistically significant, the estimated excess risk
among the elderly is very similar to that observed in the U.S. MCAPS study. Barnett et al. (2006,
089770) examined this hypothesis in New Zealand and Australia and reported no association.
      All of the above studies have identified cases of CBVD based on ICD-9 or ICD-10 codes
(most commonly ICD-9  430-438). However, the range of ICD codes commonly used in these studies
includes ischemic strokes, hemorrhagic strokes, transient ischemic attacks (TIAs) and several poorly
defined forms of acute neurological events (e.g., seizures from a vascular cause) (Table 6-7). It is
plausible that ambient PM has different effects on each of these disparate outcomes.


      Ischemic Strokes and  Transient Ischemic Attacks

      An increasing number of studies have specifically evaluated the association between PMio and
PM25 and the risk of ischemic stroke (Chan et al., 2006, 090193; Henrotin et al., 2007, 093270;
Linn  et al., 2000, 002839; Lisabeth et al., 2008, 155939; Low  et al., 2006, 090441; Szyszkowicz,
2008, 192128; Tsai  et al., 2003, 080133; Villeneuve  et al., 2006, 090191; Wellenius et al., 2005,
087483). Linn et al. (2000, 002839) found a 1.3% (95% CI: 1.0-1.6 per 10 ug/m3, PM10 lag 0) excess
risk of hospitalization for ischemic stroke in the Los Angeles metropolitan area. Wellenius et al.
(2005, 087483) reported a statistically significant 0.4% (95% CI:  0.0-0.9) excess risk per  10 ug/m3
increase in same-day PMio among elderly Medicare beneficiaries in nine U.S. cities. Low et al.
December 2009                                 6-70

-------
               reported an absolute increase of 0.08 (95% CI; 0.002-0.16) ischemic stroke
hospitalizations per 10 ug/m3 increase in PMi0 in New York City. In Kaohsiung, Taiwan, Tsai et al.
(2003, 080133) found a 5.9% (95% CI: 4.3-7.4, lag 0-2 days) excess risk of hospitalization for
ischemic stroke per 10 ug/m3 increase in PMi0 after excluding days with mean daily temperature
<20°C. Meanwhile, in Taipei, Taiwan, Chan et al. (2006, 090193) found a 3.0% (95% CI: -0.8 to 6.6,
lag 3) and 1.6% (95% CI: -0.8 to 3.9, lag 3) excess risk per 10 ug/m3 increase in PM25and PMi0,
respectively. Villeneuve et al. (2006, 090191) and Szyszkowicz et al. (2008, 192128) found no
association between either PM2.5 or PMi0 and ED visits for acute ischemic stroke in Edmonton,
Canada.
      Two recent studies are particularly noteworthy given the high specificity of the outcome
definition. Henrotin et al. (2007, 093270) used data on 1432 confirmed cases of ischemic stroke
from the French Dijon Stroke Register and found 0.9% (95% CI: -7.0 to 9.4) excess risk of ischemic
stroke per 10 ug/m  increase in PM10 on the same day and a 1.1% (95% CI: -0.2 to 9.4) excess risk
on the previous day (lag 1 day). Lisabeth et al. (2008, 155939) used data on 2,350 confirmed cases
of ischemic stroke and 1,158 cases of TIA from the Brain Attack Surveillance in Corpus Christi
Project (BASIC), a population-based stroke surveillance project designed to capture all strokes in
Nueces County, Texas. The authors found a 6.0% (95% CI: -0.8 to 13.2) and 6.0%  (95% CI: -1.8 to
14.4)  excess risk of ischemic stroke/TIA per 10 ug/m3 increase in PM2.5 on the previous day and the
same  day, respectively.
      Only the study by Villeneuve et al. (2006, 090191) specifically evaluated the association
between  ambient PM and the risk of TIAs. This study failed to find any evidence of an association
with either PM2 5 or PMi0.
      A limitation of all of these studies is that they have assessed exposure based  on the date of
hospital admission or ED presentation rather than the date and time of stroke symptom onset. It  has
been shown that this can bias health effect estimates towards the null by up to 60% (Lokken  et al.,
2009, 186774). Therefore, if there is a causal link between PM and the risk of stroke, it is likely  that
the existing studies underestimate the true effects. Moreover, most of these studies  have evaluated
only very short-term effects (lags of 0-2 days) and none have considered lags longer than 5 days. It is
possible that the lag structure of the association between PM and stroke differs from that of other
CVDs and it might even differ by stroke type.


      Hemorrhagic Strokes

      Most of the studies in the preceding section also evaluated the association between ambient
PM and the risk of hemorrhagic stroke (Chan et al., 2006, 090193: Henrotin  et al., 2007, 093270:
Tsai  et al., 2003, 080133: Villeneuve et al., 2006, 090191: Wellenius et al., 2005, 087483). In
Kaohsiung, Taiwan, Tsai et al. (2003, 080133) noted a 6.7% (95% CI: 4.2-9.4, lag 0-2 days) excess
risk of hospitalization for hemorrhagic stroke per 10  ug/m3 increase in PMi0, after  excluding days
where the mean temperature was <20°C. However, in the U.S., Wellenius et al. (2005, 088685)
failed to  find any association between ambient PMi0 levels and risk of hemorrhagic stroke among
Medicare beneficiaries in nine U.S. cities. Similarly,  Villeneuve et al. (2006, 090191) found no
evidence of an association between ED visits for hemorrhagic stroke and either PM25 or PM10 levels
in Edmonton, Canada. Henrotin et al. (2007, 093270) found no evidence of an association between
risk of hospitalization and PMi0 levels in Dijon, France, and Chan et al. (2006, 090193) found no
evidence of an association between risk of hospitalization and either PM25 or PMi0levels in Taipei,
Taiwan.
      In  summary, large studies from the U.S., Europe, and Australia/New Zealand published since
the 2004 PM AQCD (U.S. EPA, 2004, 056905) provide inconsistent support for an association
between  short-term increases in ambient levels of PM25 and PMi0 and risk of hospitalization and ED
visits  for CBVD (Figure 6-4). Studies of PMi0_2.5 and CBVD or stroke have not been conducted. The
heterogeneity in results is likely partly attributed to: (1) differences in the sensitivity and specificity
of the various outcome definitions used in the studies; (2) lag structures between PM exposure and
stroke onset which may vary by stroke type and patient characteristics; and (3) exposure
misclassification due to the use of hospital admission date rather than stroke onset  time, which may
vary by region, population characteristics, and stroke type. Effect estimates from multicity studies
and single-city U.S. and Canadian studies are included in Figure 6-4.
December 2009                                  6-71

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6.2.10.8.  Peripheral Vascular Disease

      In the U.S., the large MCAPS study Dominici et al. (2006, 088398) evaluated the association
between mean daily PM25 levels and the risk of hospitalization among elderly Medicare
beneficiaries in 204 urban counties and found that a 10 ug/m3 increase in PM2.5 was not significantly
associated with risk of hospitalization for peripheral vascular disease 0-2 days later. An earlier study
in Toronto (Burnett et al., 1999, 017269) found a negative association with PM25 (point estimate
and confidence intervals not reported), a positive statistically significant association with PMi0_25
(2.2% [95% CI: 0.1-4.3]), and a positive non-significant association with PM10 (0.5% [95% CI: -0.5
to 1.6]). The Atlanta-based SOPHIA study (Metzger et al., 2004, 044222) of ED visits grouped
visits for PVD with those for CBVD, making interpretation of these results challenging.
Study
Dominici et al. (2006, 088398)
Metzger et al. (2004, 044222)*
Delfinoetal. (2009. 191994)
Metzger et al. (2004, 044222)*
LeTertreetal. (2003, 042820)
Larrieuetal. (2007, 093031)
Villeneuve et al* (2006, 090191)
Welleniusetal. (2005. 088685)
Lisabethetal. (2008. 155939)
Villeneuve et al. (2006, 090191)*
Linn etal. (2000.002839)
Villeneuve et al. (2006, 090191)*
Wellenius et al. (2005, 088685)
Villeneuve et al. (2006, 090191)'
Age Location Lag
65+ 204 counties, U.S. 0
Northeast, U.S. 0
Southeast, U.S. 0
Midwest, U.S. 0
South, U.S. 0
All Ages Atlanta, GA 0-2
All Ages 6 counties, CA 0-1
All Ages Atlanta, GA 0-2
8 Cities, Europe 0-1
65+ 8 Cities, France 0-1
All Ages 8 Cities, France 0-1
65+ Edmonton, Canada 0-2
0-2
0-2
0-2
65+ 9 Cities, U.S. 0
All Ages Nueces County, TX 1
0
65+ Edmonton, Canada 0-2
0-2
0-2
0-2
>X Los Angeles, CA 0
65+ Edmonton, Canada 0-2
0-2
65+ 9 Cities, U.S. 0
65+ Edmonton, Canada 0-2
0-2
Outcome Effect Estimate (95% CI)
CBVD
CBVD
CBVD -I
CBVD
CBVD
CBVD/PVD
CBVD, Wildfire
CBVD/PVD
CBVD 4
CBVD -I
CBVD —I
IS roo\ c •

TIA Cool < *

IS
IS/TIA
IS/TIA
IS Cool •
iq \Afarm 	 I


IS
H° CYinl f

HS 	 1
HS Cool <
HS Warm

-* PM2.5
L-»
*•
_,_
. PMio
\
-t—
t_
PM"r



* PMio





••
PM2.5
*
— PMio
_ '

i i i \ \ i i i t i i i \ i i i
-12 -8 -4 0 4 8 12 16 20
  * ED Visits
Figure 6-4.
                                                              Excess Risk Estimate
Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.s and
concentration for CBVD ED visits and HAs. Studies represented in the
figure include all multicity studies as well as single-city studies conducted in the
U.S. and Canada.
      In summary, there is insufficient published data to determine whether or not there may be an
association between short-term increases in ambient levels ofs PM2 5, PM10_2.5s or PM10 and increased
risk of hospitalization and ED visits for PVD.


6.2.10.9.  Copollutant Models

      Relatively few studies have evaluated the effects of PM25 and PM10_2.5 on the risk of hospital
admissions and ED visits in the context of two-pollutant models. Generally, results for health effects
of both size fractions are similar even after controlling for SO2 or O3 levels (Figure 6-5). However,
December 2009
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controlling for NO2 or CO has yielded mixed results. Among the large multicity studies, the Atlanta-
based SOPHIA study found that the association between PM2.5 (total carbon) and risk of
cardiovascular ED visits was somewhat attenuated in two-pollutant models additionally controlling
for either CO or NO2 (Tolbert et al, 2007, 090316). Barnett et al. (2006, 089770) found that the
associations they observed between PM2.5 and cardiac hospitalizations in Australia and New Zealand
were attenuated after control for 24-h NO2, but not after control for CO.
      Only a few studies have attempted to evaluate the effects of one PM size fraction while
controlling for another PM size fraction. The large U.S. MCAPS study evaluating the effects of
PMio_2 5 on cardiovascular hospital admissions lost precision after controlling for PM2 5, but did not
consider gaseous pollutants (Peng  et al., 2008, 156850). Andersen et al. (2008, 189651) found that
associations between both PMi0 and PM2 5 and cardiovascular hospitalizations  in Copenhagen were
not attenuated by control for particle number concentration.
      A number of studies have also evaluated PMi0 effects in the context of two-pollutant models
with inconsistent results. The multicity Spanish EMECAS study (Ballester et al., 2006, 088746)
found that the statistically significant positive associations observed between PMi0 and cardiac
hospitalizations were robust to control for other pollutants in two-pollutant models. Jalaludin et al.
(2006, 189416) found that the effects of PMi0 as well as PM25 on cardiovascular ED visits in Sydney
Australia were attenuated by additional control for either NO2 or CO. Wellenius et al. (2005,
087483)  found that the PM10-related risk of hospitalization for CHF in Allegheny County, PA, was
attenuated in two-pollutant models controlling for either CO or NO2. In contrast, Chang et al. (2005,
080086)  examined CVD hospitalizations in Taipei and found attenuation of PMi0 effects by control
for NO2 or CO, but only during warm days. In Kaohsiung, Taiwan, Tsai et al. (2003,  080133) found
that the association between PMi0 and ischemic stroke hospitalizations was not materially  attenuated
in two-pollutant models controlling for either NO2 or CO.
      The inconsistent findings after controlling for gaseous pollutants or other size fractions are
likely due to differences in the correlation structure among pollutants, as  well as differing degrees of
exposure measurement error.
December 2009                                  6-73

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Study
Tolbertetal. (2007.090316)


Barnettetal (2006 089770)


Villeneuve et al (2006 090191)





Burnett etal (1997 084194)




Ito (2003 042856)









Moolgavkar (2003, 051316)
Jalaludin etal. (2006. 189416)

Peng etal. (2008. 156850)
Andersen etal (2008 189651)

Ito (2003 042856)









Burnett etal (1997 084194)




Peng etal. (2008. 156850)

Outcome
CVD


Heart Disease






TIE

Heart Disease




CHF




IHD




CVD
CVD

CVD
CVD

IHD




CHF









CVD

Pollutant
PM25 —I
PM25TC

PM25TC+N02
PM25

PM25+CO
PM-- <

PH-r

PH-- <

PM'r

pu"4.Mn
pM^ioV
pu'J+rn'
PM25
pM,,+n,
PM25+S02
PM25+N02
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PM25
PM25+CO J
PM25
PM25+N02
PM25+N02
PM25+N02
PM25
PM25+PM10-25
py,.
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PM |0 2r+CO
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I I I
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Effect Estimate (95% Cl)
PM2 5 Adjusted for Gases and Other Size Fractions
u —


^
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X
_
PMm ; Adjusted for Gases and Other Size Fractions
_




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*
I I I I I I I I
) 2 4 6 8 10 12 14 16
                                                 Excess Risk (%)
Figure 6-5.    Excess risk estimates per 10 ug/m  increase in 24-h avg PM2.6, and PMi0.2.s for
              cardiovascular disease ED visits or HAs, adjusted for co-pollutants.
December 2009
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6.2.10.10. Concentration Response

      The concentration-response relationship has been extensively analyzed primarily through
studies that examined the relationship between PM and mortality. These studies, which have focused
on short- and long-term exposures to PM have consistently found no evidence for deviations from
linearity or a safe threshold (Daniels et al., 2004, 087343; Samoli et al., 2005, 087436; Schwartz,
2004, 078998; Schwartz  et al., 2008, 156963) (Sections 6.5.2.7 and 7.1.4). Although on a more
limited basis, studies that have examined PM effects on cardiovascular hospital admissions and ED
visits have also analyzed the PM concentration-response relationship, and contributed to the overall
body of evidence which suggests a log-linear, no-threshold PM concentration-response relationship.
      The evaluation of cardiovascular hospital admission and ED visit studies in 2004 PM AQCD
(U.S. EPA, 2004, 056905) found no evidence for a threshold in the dose-response relationship
between short-term exposure to  PMi0and IHD hospital admissions (Schwartz  and Morris, 1995,
046186). An evaluation of recent single- and multicity studies of hospital admission and ED visits
for CVD further supports this  finding.
      Ballester et al. (2006, 088746) examined the linearity of the relationship between air
pollutants (including PM10) and  cardiovascular hospital admissions in 14 Spanish cities within the
EMECAM project. In this exploratory analysis, the authors examined the models used when
pollutants were added in either a linear or non-linear way (i.e., with a spline smoothing function) to
the model. Although the study does not present the results for each of the pollutants evaluated
individually, overall Ballester et al. (2006, 088746) found that the shape of the pollutant-
cardiovascular hospital admission relationship was most compatible with a linear curve. Wellenius
et al. (2005, 087483) conducted a similar analysis when examining the relationship between PM10
and CHF hospital admissions  among Medicare beneficiaries. The authors examined the assumption
of linearity using fractional polynomials and linear splines. The results of both approaches
contributed to Wellenius et al. (2005, 087483) concluding that the assumption of linearity between
the log relative risk of cardiovascular hospital  admissions and PM concentration was reasonable.
      Unlike the aforementioned studies that examined the linearity in the concentration-response
curve as part of the model selection process (i.e., to determine the most appropriate model to use to
examine the relationship between PM and cardiovascular hospital admissions and ED visits),
Zanobetti and Schwartz (2005, 088069) conducted an extensive analysis of the shape of the
concentration-response curve  and the potential presence of a threshold when examining the
association between PMi0 and MI hospital admissions among older adults in 21 U.S. cities. The
authors examined the concentration-response curve by fitting a piecewise linear spline with slope
changes at 20 and 50 ug/m3. This approach resulted in an almost linear concentration-response
relationship between PMi0 and MI hospital admissions with a steeper slope occurring below
50 ug/m3 (Figure 6-6). Additionally, Zanobetti and Schwartz (2005, 088069) found no evidence for a
threshold.
December 2009                                  6-75

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                         7.0


                      i6-"
                      •- 5.0
                      05
                      Cfl
                      | 4.0
                      o
                      .= 3.0

                      8 2.0

                      <2 1,0

                         0.0
0
10
 I
20
 I
30
     1
    40
                                                       I
                                                      50
80   70    80
                                                                   Source: Zanobetti and Schwartz (2005, 0880691.

Figure 6-6.    Combined random-effect estimate of the concentration-response relationship
              between Ml emergency hospital admissions and PMi0, computed by fitting a
              piecewise linear spline, with slope changes at 20 ug/m3 and 50 ug/m3.

      Overall, the limited evidence from the studies that examined the concentration-response
relationship between PM and cardiovascular hospital admissions and ED visits supports a no-
threshold, log-linear model, which is consistent with the observations made in studies that examined
the PM-mortality relationship (Section 6.5.2.7).


6.2.10.11. Out of Hospital Cardiac Arrest

      One study of out of hospital cardiac death conducted in Seattle, WA (Checkoway et al., 2000,
015527). which reported no association with PM was included in the 2004  PM AQCD (U.S. EPA,
2004, 056905). In the U.S., the survival rate of sudden cardiac arrest is less than 5%. In addition, as
discussed in Section 6.5, Zeka et al. (2006, 088749) found that the estimated mortality risk due to
short-term exposure to PM10 was much higher for out-of-hospital cardiovascular deaths than for
in-hospital cardiovascular deaths. The analysis of studies that examine the association between PM
and cardiac arrest could provide evidence for an important link between the morbidity and mortality
effects attributed to PM.
      Sullivan et al. (2003, 043156) examined the association between the  incidence of primary
cardiac arrest and daily measures of PM2.5 (measured by nephelometry) using a case-crossover
analysis of 1,206 Washington State out-of-hospital cardiac arrests (1985-1994) among persons with
(n = 774) and without (n = 432) clinically recognized heart disease. The authors examined PM
associations at 0- through 2-day lags using the time-stratified referent sampling scheme (i.e., the
same day of the week and month of the same year). The estimated relative risk for a 13.8-ug/m3
increase in 1-day lag PM2.5 (nephelometry: IQR = 0.54 10"1 km"1 bsp) was 0.94 (95% CI:  0.88-1.02),
or 0.96 (95% CI: 0.91-1.0) per 10 ug/m3 increase. Similar estimates were reported for 0- or 2-day
lags. The presence or absence of clinically recognized heart disease did not alter the result. This
finding is consistent with the previous study of cardiac arrest in Seattle (Levy et al., 2001, 017171)
that reported no PM association. It is also consistent with the Sullivan et al. (2005,  050854) analysis
of PM and onset of MI, and the Sullivan et al. (2007, 100083) analysis of PM and blood markers of
inflammation in the elderly population, both of which were conducted in Seattle. Note also that the
analysis of the NMMAPS data for the years 1987-1994 also found no PMi0 association for all-cause
mortality in Seattle. Overall, the results of studies conducted in Seattle consistently found no
association between PM and cardiovascular outcomes or all-cause mortality.
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      Rosenthal et al. (2008, 156925) examined associations between PM2.5 and out-of-hospital
cardiac arrests in Indianapolis, Indiana for the years 2002-2006 using a case-crossover design with
time-stratified referent sampling. Using all the cases (n = 1,374), they found no associations between
PM2.5 and cardiac arrest in any of the 0- through 3-day lags or multiday averages thereof (e.g., for
0-day lag, OR =1.02 [CI: 0.94-1.11] per 10 (ig/m3 increase in PM2.5). However, for cardiac arrests
witnessed by bystanders (n = 511), they found a significant association with PM25 exposure (by
TEOM, corrected with FRM measurements) during the hour of the arrest (OR =1.12 [CI: 1.01-1.25]
per 10 (ig/m3 increase in PM25), and even larger risk estimates for older adults (age 60-75) or those
that presented with asystole. There have been  very few PM studies that used hourly PM
measurements, and further studies are needed  to confirm associations at such time scales.
      In Rome, Forastiere et al.  (2005, 086323) examined associations between air pollution (PNC,
PMio, CO, NO2, and O3) and out-of-hospital coronary deaths (n = 5,144) for the study period of
1998-2000. A case-crossover design with the time-stratified referent sampling was used to examine
the pollution indices at lag 0- through 3 days and the average of 0-1 lags. They found associations
between deaths and PNC (lag 0 and 0-1), PMi0 (lag 0,  1, and 0-1), and CO (lag 0 and 0-1) but not
with NO2 or O3. The risk estimate for 0-day lag PMi0 was 1.59% (CI: 0.03-3.18) per 10 ug/m3
increase. The older adults (65-74 and >75 age groups)  showed higher risk estimates than the younger
(35-64) age group. Because PNC is considered to be associated with UFPs, and CO was also
associated with out-of-hospital cardiac arrests, combustion sources were implicated.
      In summary, only a few studies have examined out-of-hospital cardiac arrest or deaths. The
two studies from Seattle, WA consistently found no association (also consistent with other cardiac
effects and mortality studies conducted in that locale);  a study in Indianapolis, IN found an
association with hourly PM2 5 but not daily PM2 5; and  a study in Rome found an association with
PMio, but also with PNC and CO. Because multicity mortality studies examining this association
found heterogeneity in PM risk estimates across regions, future studies of out-of-hospital cardiac
arrest will need to consider location and the air pollution mixture during their design. Mean and
upper percentile concentrations are found in Table 6-9.
Table 6-9.    PM concentrations reported in studies of out-of-hospital cardiac arrest.
         Author
        Location
 Mean Concentration (ug/m3
PM2.5
Sullivan et al. (2003, 043156)
Washington State
Nephelometry:0.71 x10"1 km"1 bsp Maximum: 5.99 x 10"1 km"1 bsp
Rosenthal et al. (2008,156925)    Indianapolis, Indiana
                                             NR
                                                                    NR
PM,,
Sullivan et al. (2003, 043156)
Washington State
                                             28.05
                                                                    89.83
Zeka et al. (2006, 088749)
                       Range in Means: 15.9 (Honolulu) -  MR
                       37.5 (Cleveland)            INK
Forastiere etal. (2005,086323)    Rome, Italy
                                             52.1
                                                                    75th: 65.7
6.2.11. Cardiovascular Mortality
      An evaluation of studies that examined the association between short-term exposure to PM2 5
and PMio_2.5 and mortality provides additional evidence for PM-related cardiovascular health effects.
Although the primary analysis in the majority of mortality studies evaluated consists of an
examination of the relationship between PM2 5 or PMi0_2.5 and all-cause (nonaccidental) mortality,
some studies have examined associations with cause-specific mortality including cardiovascular-
related mortality.
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      Multicity mortality studies that examined the PM2 5-cardiovascular mortality relationship on a
national scale (Franklin et al. (2007, 091257) - 27 U.S. cities; Franklin et al. (2008, 155779) - 25
U.S. cities; and Zanobetti and Schwartz (2009, 188462) - 112 U.S. cities) have found consistent
positive associations between short-term exposure to PM2 5 and cardiovascular mortality ranging
from 0.47 to 0.85% per 10(ig/m3 at lag 0-1 (Section 6.5).  The associations observed on a national
scale are consistent with those presented by Ostro et al. (2006,  087991) in a study that examined the
PM2 ^-mortality relationship in nine California counties (0.6% [95% CI: 0-1.1] per 10 (ig/m3). Of the
multicity studies evaluated, one examined single day lags and found evidence for slightly larger
effects at lag 1 compared to the average of lag days 0 and 1 for cardiovascular mortality (94%
[95% CI: -0.14 to 2.02] per 10 ug/m3) (Franklin  et al., 2007, 091257). Although the overall effect
estimates reported in the multicity studies evaluated are consistently positive,  it should be noted that
a large degree  of variability exists between cities when examining city-specific effect estimates
potentially due to differences between cities and regional differences in PM2 5 composition  (Figure
6-24). Only a limited number of studies that examined the PM2 5-mortality relationship have
conducted analyses of potential  confounders, such as gaseous copollutants, and none examined the
effect of copollutants on PM25 cardiovascular mortality risk estimates. Although the recently
evaluated multicity studies did not extensively examine whether PM2 5 mortality risk estimates are
confounded by gaseous copollutants, evidence from the limited number of single-city studies
evaluated in the 2004 PM AQCD (U.S. EPA, 2004, 056905) suggests that gaseous copollutants do
not confound the PM2 5-cardiovascular mortality association. This is further supported by studies that
examined the PMi0-mortality relationship in both the 2004 PM AQCD (U.S. EPA, 2004, 056905)
and this review. The evidence from epidemiologic, controlled human exposure, and toxicological
studies that examined the association between short-term exposure to PM2 5 and cardiovascular
morbidity provide coherence and biological plausibility for the cardiovascular mortality effects
observed. Overall, the cardiovascular mortality PM2 5 effects were similar to those reported for all-
cause (nonaccidental) mortality  (Section 6.5), and are consistent with the effect estimates observed
in the single- and multicity studies evaluated in the 2004  PM AQCD (U.S. EPA, 2004, 056905).
      Zanobetti and Schwartz (2009, 188462) also examined PMi0_2.5 mortality associations in 47
U.S. cities and found evidence for cardiovascular mortality effects (0.32% [95% CI: 0.00-0.64] per
10 (ig/m at lag 0-1) similar to those reported for all-cause (nonaccidental) mortality (0.46% [95% CI:
0.21-0.67] per 10 (ig/m). In addition, Zanobetti and Schwartz (2009, 188462)  reported seasonal (i.e.,
larger in spring and summer) and regional differences in PMi0_2.5 cardiovascular mortality risk
estimates. A few single-city studies evaluated also reported associations, albeit somewhat larger than
the multicity study, between PMi0_25 and cardiovascular mortality in Phoenix, AZ (Wilson  et al.,
2007, 157149) (3.4-6.6% at lag  1) and Vancouver, Canada (Villeneuve et al.,  2003, 055051) (5.4%
at lag 0). The difference in the PMi0_2.5 risk estimates observed between the multi- and single-city
studies could be due to a variety  of factors including differences between cities and compositional
differences in PMi0_2.5 across regions (Figure 6-29). Only  a small number of studies have examined
potential confounding by gaseous copollutants or the influence of model specification on PMi0_2.s
mortality risk estimates, but the effects are relatively consistent with those studies evaluated in the
2004 PM AQCD (U.S.  EPA, 2004, 056905).


6.2.12. Summary and Causal  Determinations



6.2.12.1.  PM2.5

      Several studies cited in the 2004 AQCD reported positive associations between short-term
PM2 5 concentrations and hospital admissions or ED visits for CVD, although  few were statistically
significant. In addition, U.S. and Canadian-based studies  (both multi- and single-city) that examined
the PM2 ^-mortality relationship reported associations for cardiovascular mortality consistent with
those observed for all-cause (nonaccidental) mortality and relatively stronger than those for
respiratory mortality. Significant associations were also observed between MI and short-term PM2 5
concentrations (averaged over 2 or 24 h), as well as decreased HRV in association with PM2 5.
Several controlled human exposure and animal toxicological studies demonstrated HRV effects from
exposure to PM2 5 CAPs,  as well as changes in blood coagulation markers. However, the effects in
these studies were variable. Arrhythmogenesis was reported for toxicological  studies and generally
December 2009                                  6-78

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these results were observed in animal models of disease (SH rat, MI, pulmonary hypertension)
exposed to combustion-derived PM2.5 (i.e., ROFA, DE, metals). One study demonstrated significant
vasoconstriction in healthy adults following controlled exposures to CAPs, although this response
could not be conclusively attributed to the particles as subjects were concomitantly exposed to
relatively high levels of O3. The results reported for systemic inflammation in toxicological studies
were mixed.
     A large body of evidence from studies of the effect of PM2.5 on hospital admissions and ED
visits for CVD has been published since the 2004 PM AQCD. Associations with PM2 5 are
consistently positive with the majority of studies reporting increases in hospital admissions or ED
visits ranging from 0.5 to 3.4% per 10 ug/m3 increase in PM25 (Section 6.2.10). The largest U.S-
based multicity study, MCAPs, reported excess risks in the range of approximately 0.7% with the
largest excess risks in the Northeast (1.08%) and in the winter (1.49%), providing evidence of
regional and seasonal heterogeneity (Bell et al., 2008, 156266; Dominici et al, 2006,  088398).
Weak or null findings for PM2 5 have been observed in two single-city studies both conducted in
Washington state (Slaughter et al.,  2005, 073854; Sullivan et al., 2007, 100083) and may be
explained by this heterogeneity. Weak associations were also reported in Atlanta for PM2 5 and CVD
ED visits, with PM2 5 traffic components being more strongly associated with CVD ED visits than
other components (Tolbert et al., 2007, 090316).  Multicity studies conducted outside the U.S.  and
Canada have shown positive associations with PM2 5. Studies of specific CVD outcomes indicate that
IHD and CHF may be driving the observed associations (Sections 6.2.10.3 and 6.2.10.5,
respectively). Although estimates from studies of cerebrovascular diseases are less precise and
consistent, ischemic diseases appear to be more strongly associated with PM2 5 compared to
hemorrhagic stroke (Section 6.2.10.7). The available evidence  suggests that these effects occur at
very short lags (0-1 days), although effects at longer lags have  rarely been evaluated. Overall, the
results  of these studies provide support for associations between short-term PM25 exposure and
increased risk of cardiovascular hospital admissions in areas with mean concentrations ranging from
7 to 18 ug/m3.
     Epidemiologic studies that examined the association between PM2 5 and mortality provide
additional evidence for PM25-related cardiovascular effects (Section 6.2.11). The multicity studies
evaluated found consistent, precise positive associations between short-term exposure to PM2 5 and
cardiovascular mortality ranging from 0.47 to 0.85% at mean 24-h avg PM25 concentrations above
13 ug/m3. These associations were reported at short lags (0-1 days), which is consistent with the
associations observed in the hospital admission and ED visit studies discussed above. Although only
a limited number of studies examined potential confounders of the PM2 5-cardiovascular mortality
relationship, the studies evaluated in both this review and the 2004 PM AQCD (U.S. EPA, 2004,
056905) support an association between short-term exposure to PM2 5  and cardiovascular mortality.
     Recent studies that apportion ambient PM2 5 into sources and components suggest that
cardiovascular hospital admissions  associated with PM2 5 may be attributable to traffic-related
pollution and, in some cases, biomass burning (Section 6.2.10). Further supporting evidence is
provided by studies that have used PMi0 collection filters (median diameter generally <2.5 um) to
identify combustion- or traffic-related sources associated with cardiovascular hospital admissions.
Metals have also been implicated in these effects (Bell et al., 2009,  191997). A limited number of
older publications have reported that particle acidity of PM25 is not more strongly associated with
CVD hospitalizations or ED visits than other PM  metrics.
     Changes in various measures of cardiovascular function have been demonstrated by multiple
independent laboratories following controlled human exposures to different types of PM2 5. The most
consistent effect is changes in vasomotor function, which has been demonstrated following exposure
to CAPs and DE. The majority of the new evidence of particle-induced changes in vasomotor
function comes from studies of exposures to DE (Section 6.2.4.2). None of these studies have
evaluated the effects of DE with and without a particle trap. Therefore, the changes in vasomotor
function cannot be conclusively attributed to the particles in DE as subjects are also concomitantly
exposed to relatively high levels of NO2, NO, CO, and hydrocarbons. However, it is important to
note that a study by Peretz et al. (2008, 156854) used a newer diesel engine with lower gaseous
emissions and reported significant DE-induced decreases in BAD. In addition, increasing the particle
exposure concentration from 100 to 200 ug/m3, without proportional increases in NO, NO2, or CO,
resulted in an approximate 100% increase in response. An additional consideration is that, while
fresh DE used in these studies contains relatively high concentrations of PM25, the MMAD is
typically < 100 nm, which makes it difficult to determine whether the observed effects are due to
December 2009                                  6-79

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PM2.5 or, more specifically, due to the UF fraction. Further evidence of a particle effect on vasomotor
function is provided by significant changes in BAD demonstrated in healthy adults following
controlled exposure to CAPs with O3 (Brook et al., 2002, 024987). These findings are consistent
with epidemiologic studies of various measures of vasomotor function (e.g., FMD and BAD were
the most common), which have demonstrated an association with short-term PM2.5 concentration in
healthy and diabetic populations (Section 6.2.4.1). A limited number of epidemiologic studies
examined multiple lags and the strongest associations were with either the 6-day mean concentration
(O'Neill et al., 2005, 088423) or the concurrent day (Schneider et al., 2008, 191985).
      The toxicological findings with respect to vascular reactivity are generally in agreement and
demonstrate impaired dilation following PM2 5  exposure that is likely endothelium dependent
(Section 6.2.4.3). These effects have been demonstrated in varying vessels and in response to
different PM2.5 types, albeit using IT instillation exposure in most studies. Further support is
provided by IT instillation studies of ambient PM10 that also demonstrate impaired vasodilation and a
PM25 CAPs study that reported decreased L/W ratio of the pulmonary artery. An inhalation study of
Boston PM2 5 CAPs reported increases in coronary vascular resistance during ischemia, which
indicated a possible role for PM-induced coronary vasoconstriction. The mechanism behind impaired
dilation following PM exposure may include increased ROS and RNS production in the
microvascular wall that leads to altered NO bioavailability and endothelial dysfunction. Despite the
limited number of inhalation studies conducted with concentrations near ambient levels, the
toxicological studies  collectively provide coherence and biological plausibility for the myocardial
ischemia observed in controlled human exposure and epidemiologic studies.
      Consistent with the observed effects on vasomotor function, one recent controlled human
exposure study reported an increase in exercise-induced ST-segment depression (a potential indicator
of ischemia) during exposure to DE in a  group  of subjects with prior MI (Mills  et al., 2007,
091206). In addition, toxicological studies from Boston that employed CAPs provide further
evidence for PM2 5 effects  on ischemia, with changes in ST-segment and decreases in total
myocardial blood flow reported (Section 6.2.3.3). These findings from toxicological and  controlled
human exposure studies provide coherence and biological plausibility for the associations observed
in epidemiologic studies, particularly those of increases in hospital admissions and ED visits for
IHD. Several epidemiology studies have reported associations between short-term PM2 5
concentration (including traffic sources or components such as BC) and ST-segment depression or
abnormality (Section 6.2.3.1).
      Toxicological studies provide biological plausibility for the PM2 5 associations with CHF
hospital admissions by  demonstrating increased right ventricular pressure and diminished cardiac
contractility in rodents  exposed to CB  and DE (Section 6.2.6.1). Similarly, increased coronary
vascular resistance was observed following PM2 5 CAPs exposure in dogs with
experimentally-induced ischemia. Further, a recent epidemiology  study reported small but
statistically significant decreases in passively monitored diastolic pressure and right ventricular
diastolic pressure (Rich et al., 2008, 156910).
      In addition to the effects of PM on vasomotor response, there is a growing body of evidence
that demonstrates changes in markers of systemic oxidative stress following controlled human
exposures to DE, wood smoke, and urban traffic particles. However, these effects may be driven in
part by the UF fraction of PM25. Toxicological  studies provide evidence of increased cardiovascular
ROS following PM2 5 exposure to CAPs, road dust, CB, and TiO2, as well as increased systemic ROS
in rats exposed to gasoline exhaust (Section 6.2.9.3). Epidemiologic studies of markers of oxidative
stress (e.g., tHcy, CuZn-SOD, TEARS, 8-oxodG, oxLDL and MDA) are consistent with these
toxicological findings (Section 6.2.9.1).
      A few epidemiologic studies of ventricular arrhythmias recorded on ICDs that were conducted
in Boston and Sweden (Table 6-2) found associations with short-term PM2 5 concentration (also BC
and sulfate). While Canadian and U.S. studies conducted outside of Boston  did not find positive
associations between PM2 5 and ICD recorded ventricular arrhythmias, several such studies observed
associations with ectopic beats and runs  of supraventricular or ventricular tachycardias (Section
6.2.2.1). Toxicological  studies also provide limited evidence of arrhythmia,  mainly in susceptible
animal models (i.e., older rats, rats with CHF) (Section 6.2.2.2).
      Most epidemiologic studies of HRV have reported decreases in SDNN, LF, HF, and rMSSD
(Section 6.2.1.1). While there are also  a significant number of controlled human exposure studies
reporting PM-induced changes in HRV, these changes are often variable and difficult to interpret
(Section 6.2.1.2). Similarly, HRV increases and decreases have been observed in animal
December 2009                                  6-80

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toxicological studies that employed CAPs or CB (Section 6.2.1.3). In a study in mice, resuspended
soil, secondary sulfate, residual oil, and motor vehicle/other sources, as well as Ni were implicated in
HRV effects (Lippmann et al., 2006, 091165). Further, cardiac oxidative stress has been implicated
as a consequence of ANS stimulation in response to CAPs. Modification of the PM-HRV association
by genetic polymorphisms related to oxidative stress has been observed in a series of analyses of the
population enrolled in the Normative Aging Study. Changes in HRV measures (whether increased  or
decreased) are likely to be  more useful as indicators of PM exposure rather than predictive of some
adverse outcome. Furthermore, the HRV result may be reflecting a fundamental response of an
individual that is determined in part by a number of factors including age and pre-existing
conditions.
      Although not consistently observed across studies, some investigators have reported
PM2.5-induced changes in BP, blood coagulation markers, and markers of systemic inflammation in
controlled human exposure studies (Sections 6.2.5.2, 6.2.8.2, and 6.2.9.2, respectively). Findings
from epidemiologic studies, which are largely  cross-sectional and measure a wide array markers of
inflammation and coagulation, are not consistent; however, a limited number of recent studies of
gene-environment interactions offer insight into potential individual susceptibility to these effects
(Ljungman et al., 2009, 191983: Peters  et al., 2009, 191992). Similarly, toxicological studies
demonstrate mixed results  for systemic inflammatory markers and generally indicate relatively little
change at 16-20 h post-exposure (Section 6.2.7.3).  Increases in BP have been observed in
toxicological studies (Section 6.2.5.3), with the strongest evidence coming from dogs exposed to
PM2.5 CAPs. For blood coagulation parameters, the most commonly reported change in animal
toxicological studies is elevated plasma fibrinogen levels following PM2 5 exposure, but this
response is not consistently observed (Section  6.2.8.3).
      In summary,  associations of hospital admissions or ED visits with PM2.5 for CVD
(predominantly  IHD and CHF) are consistently positive with the majority of studies reporting
increases ranging from 0.5 to 3.4% per 10 ug/m increase in PM25. Seasonal and regional variation
observed in the large multicity study of Medicare recipients is consistent with null findings reported
in several single city studies conducted in the Western U.S. The results from the hospital admission
and ED visit studies are  supported by the associations  observed  between  PM2 5 and cardiovascular
mortality, which also provide additional evidence for regional and seasonal variability in PM2 5 risk
estimates. Changes in  various measures of cardiovascular function that may explain these
epidemiologic findings have been demonstrated by multiple independent laboratories following
controlled human exposures to different types  of PM25. The most consistent PM25 effect is for
vasomotor function, which has been demonstrated  following exposure to CAPs and DE.
Toxicological studies finding reduced myocardial blood flow during ischemia and altered vascular
reactivity provide coherence and biological plausibility for the myocardial ischemia that has been
observed in both controlled human exposure and epidemiologic studies. Further, PM2 5  effects on ST-
segment depression have been observed across disciplines. In addition to ischemia, PM2 5 may act
through several other pathways. Plausible biological mechanisms (e.g., increased right ventricular
pressure and diminished cardiac contractility) for the associations of PM25 with CHF have also been
proposed based on toxicological findings. There is  a growing body of evidence from controlled
human exposure, toxicological and epidemiologic studies demonstrating changes in markers of
systemic oxidative  stress with PM2 5 exposure. Inconsistent effects of PM on BP, blood coagulation
markers and markers of systemic inflammation have been reported across the disciplines. Together,
the collective evidence is sufficient to conclude that a causal relationship exists between
short-term  PM25 exposures and cardiovascular effects


6.2.12.2.  PM10.2.5

      There was little  evidence in the 2004 AQCD regarding PMi0_2.5 cardiovascular health effects.
Two single-city epidemiologic studies found positive associations of PMi0_25 with cardiovascular
hospital admissions in Toronto (Burnett  et al., 1999, 017269) and Detroit, MI (Ito, 2003, 042856;
Lippmann, 2000, 024579)  and the effect estimates  were of the same general magnitude as for PMi0
and PM2 5. Both studies reported positive associations  and estimates appeared robust to adjustment
for gaseous copollutants in two-pollutant models. An imprecise, non-significant association between
PMio_2.5 and onset of MI was observed in Boston (Peters et al., 2001, 016546). No controlled human
exposure or toxicological studies of PMi0_2.5 were presented in the 2004 AQCD.
December 2009                                  6-81

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      Several recent epidemiologic studies of the effect of ambient PM10_2.5 concentration on hospital
admissions or ED visits for CVD were conducted (Section 6.2.10). In a study of Medicare patients in
108 U.S. counties, Peng et al. (2008,  156850) reported a significant association between PMi0_2.5 and
CVD hospitalizations in their single pollutant model. In a study of six French cities, Host et al.
(2008, 155852) reported a significant increase in IHD hospital admissions in association with PMi0_
25. In contrast, associations of cardiovascular outcomes with PMi0_25 were weak for CHF and null
for IHD in the Atlanta-based SOPHIA study (Metzger  et al., 2004, 044222). Results from single-city
studies are generally positive, but effect sizes are heterogeneous and estimates are imprecise
(Section 6.2.10). Crustal material from a dust storm in the Gobi desert that was largely coarse PM
(generally indicated using PMi0) was associated with hospitalizations for CVD, including IHD and
CHF in most studies (Section 6.2.10). Mean PMi0_2.5 concentrations in the hospital admission and
ED visit studies ranged from 7.4-13 ug/m3. A few epidemiologic studies that examined the
association between short-term exposure to PM10_2.5 and cardiovascular mortality (Section 6.2.11)
provide supporting evidence for the hospital admission and ED visit studies at similar 24-h avg
PMio_2.5 concentrations (i.e., 6.1-16.4 ug/m3). Amulticity study reported risk estimates for
cardiovascular mortality of similar magnitude to those for all-cause (nonaccidental) mortality
(Zanobetti  and Schwartz, 2009, 188462). However, the single-city studies evaluated (Villeneuve  et
al., 2003, 055051;  Wilson et al., 2007, 157149) reported substantially larger effect estimates, but this
could be due to differences between cities and compositional differences in PM10_2.5 across regions.
Of note is the lack of analyses within the studies evaluated that examined potential confounders of
the PMio_2.5-cardiovascular mortality  relationship.
      The U.S. study of Medicare patients (Peng et al., 2008, 156850) and the multicity study that
examined the association between PMi0_2.5 and mortality (Zanobetti and Schwartz, 2009, 188462)
were the only studies to adjust PMi0_2.5 for PM2.5. Peng, et al. (2008, 156850) found that the PMi0_2.5
association with CVD hospitalizations remained, but diminished slightly after adjustment for PM2.5.
These results are consistent with those reported by Zanobetti and Schwartz (2009, 188462). which
found PMio_2.5-cardiovascular mortality risk estimates remained relatively robust to the inclusion of
PM2.5 in the model. Because of the greater spatial heterogeneity of PMi0_2.5, exposure measurement
error is more likely to bias health effect estimates towards the null for epidemiologic studies of
PMio_2.5 versus PMi0 or PM2.5, making it more difficult to detect an effect of the coarse size fraction.
In addition, models that include both  PM10_2.5 and PM2.5 may suffer from instability due to
collinearity. Further, the lag structure of PMi0_2.5 effects on risk of cardiovascular hospital admissions
and ED visits, as well as mortality, has not been examined in detail.
      Several epidemiologic studies of cardiovascular endpoints including HRV, BP, ventricular
arrhythmia, and ECG changes indicating ectopy or ischemia were conducted since publication of the
2004 PM AQCD.  Supraventricular ectopy and ST-segment depression were associated with PMi0_2.5
(Section 6.2.3.1), and the only study to examine the effect of PM10_25 on BP reported a decrease in
SBP (Ebelt et al., 2005, 056907) (Section 6.2.5.1). HRV findings were mixed across the
epidemiologic studies (Section 6.2.1.1). A limited number of studies have evaluated the effect of
controlled exposures to PMi0_2.5 CAPs on cardiovascular endpoints in human subjects. These studies
have provided some evidence of decreases in HRV (SDNN) and tPA concentration among healthy
adults approximately 20 hours following exposure (Section 6.2.1.2). However, it is important to note
that no other measures of HRV (e.g.,  LF, HF, or LF/HF), nor other hemostatic  or thrombotic markers
(e.g., fibrinogen) were significantly affected by particle exposure in these studies.
      There are very few toxicological studies that examined the effect of exposure to PMi0_2.5 on
cardiovascular endpoints or biomarkers in animals. The few studies that evaluated cardiovascular
responses were comparative studies of various size fractions, and only blood or plasma parameters
were measured (Sections 6.2.7.3 and  6.2.8.3). These studies used IT instillation methodologies, as
there are challenges to exposing rodents via inhalation to PM 10.2,5, due to near  100% deposition in
the ET region for particles >5 urn (Raabe et al., 1988, 001439) and only 44%  nasal inhalability of a
10 urn particle in the rat (Menache et al., 1995, 006533). These studies also employed relatively
high doses of PMi0_2.s. Despite these shortcomings, increased plasma fibrinogen was observed and
the response was similar to that observed with PM2.5. At this time, evidence of biological plausibility
for cardiovascular morbidity effects following PMi0_2.5 exposure is sparse, due to the small number
of studies, few endpoints examined, and the limitations related to the interpretation of IT instillation
exposures.
      In summary, several epidemiologic studies report associations with cardiovascular endpoints
including IHD hospitalizations,  Supraventricular ectopy, and changes in HRV.  Further, dust storm
December 2009                                  6-82

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events resulting in high concentrations of crustal material are linked to increases in cardiovascular
disease hospital admissions or ED visits for cardiovascular diseases. A large proportion of inhaled
coarse particles in the 3-6 urn (dae) range can reach and deposit in the lower respiratory tract,
particularly the TB airways (Figures 4-3 and 4-4). The few toxicological and controlled human
exposure studies examining the effects of PMi0_2.5 provide limited evidence of cardiovascular effects
and biological plausibility to support the epidemiologic findings. Therefore the available evidence is
suggestive of a causal relationship between PM,,,  exposures and cardiovascular
effects


6.2.12.3.  UFPs

      There was very little evidence available in the 2004 PM AQCD (U.S. EPA, 2004, 056905) on
the cardiovascular effects of UFPs. Findings from one study presented in the 2004 PM AQCD
(U.S. EPA, 2004, 056905) of controlled exposures to UF EC suggested no particle-related effects on
various cardiovascular endpoints including blood coagulation, HRV, and systemic inflammation. No
epidemiologic studies of short-term UFP concentration and cardiovascular endpoints were included
in the 2004 AQCD and there were no relevant toxicological studies reviewed in the 2004 PM AQCD
(U.S. EPA, 2004, 056905) that exposed animals to UFPs.  A small number of new epidemiologic
studies, as well as several controlled human exposure and toxicological studies have been conducted
in recent years, but substantial uncertainties remain as to the cardiovascular effects of UFPs. For a
given mass, the enormous number and large surface area of UFPs highlight the importance of
considering the size of the particle in assessing response.  For example, UFPs with a diameter of
20 nm, when inhaled at the same mass concentration, have a number concentration that is
approximately six orders of magnitude higher than for a 2.5-um diameter particle. Particle surface
area is also greatly increased with  UFPs. Many studies suggest that the surface of particles or
substances released from the surface (e.g., transition metals, organics) interact with biological
substrates, and that surface-associated free radicals or free radical-generating systems may be
responsible for toxicity, resulting in greater toxicity of UFPs per particle surface area than larger
particles. Additionally, smaller particles may have greater potential to cross cell membranes and
epithelial barriers.
      Controlled human exposure studies are increasingly being utilized to evaluate the effect of
UFPs on cardiovascular function. While the number of studies of exposure to UFPs is still limited,
there is a relatively large body of evidence from exposure to fresh DE, which is typically dominated
by UFPs. As described under the summary for PM2.s, studies of controlled exposures to DE (100-300
ug/m3) have consistently demonstrated effects on vasomotor function among adult volunteers
(Section 6.2.4.2). In addition, exposure to UF EC (50 ug/m3, 10.8xl06 particles/cm3) was  recently
shown to attenuate FMD (Shah  et al., 2008, 156970). Changes in vasomotor function have been
observed in animal toxicological studies of UFPs, although very few studies have been conducted
(Section 6.2.4.3). Inhaled UF TiO2 impaired arteriolar dilation when compared to fine TiO2 at similar
mass doses (Nurkiewicz et al., 2008, 156816). This response may have been due to ROS  in the
microvascular wall, which may have led to consumption of endothelial-derived NO and generation
of peroxynitrite radicals. Support for an UFP effect on altered vascular reactivity is also provided by
studies of DE and IT instillation exposure to ambient PM. The response to DE did not appear to be
due to VOCs. One epidemiologic study showed that PNC was associated with a nonsignificant
decrease in flow- and nitroglycerine-mediated reactivity as measures of vasomotor function in
diabetics living in Boston (O'Neill et al., 2005, 088423).
      New studies have reported increases in markers of systemic oxidative stress in humans
following controlled exposures to different types of PM consisting of relatively  high concentrations
of UFPs from sources including  wood smoke, urban traffic particles, and DE (Section 6.2.9.2).
Increased cardiac oxidative stress has been observed in mice and rats following gasoline exhaust
exposure and it appeared the effect was particle-dependent (Section 6.2.9.3).
      The associations between  UFPs and HRV measures in epidemiologic studies include increases
and decreases (Section 6.2.1.1),  providing some evidence for an effect. Exposure to UF CAPs has
been observed to alter parameters of HRV in controlled human exposure studies, although this effect
has been variable between studies  (Section 6.2.1.2). Alterations in HR, HRV, and BP were reported
in rats exposed to <200 ug/m3 UF  CB (<1.6xl07 particles/cm3) (Sections 6.2.1.3 and 6.2.5.3). The
effects of UFPs on BP have been mixed in epidemiologic studies (Section 6.2.5.1).
December 2009                                 6-83

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      There is some evidence of changes in markers of blood coagulation in humans following
controlled exposure to UF CAPs, as well as wood smoke and DE; however, these effects have not
been consistently observed across studies (Section 6.2.8.2). Toxicological studies demonstrate mixed
results for systemic inflammation and blood coagulation as well (Sections 6.2.7.3 and 6.2.8.3).
      Few time-series studies of CVD hospital admissions have evaluated UFPs. The SOPHIA study
found no association between any outcome studied (all CVD, dysrhythmia, CHF, IHD, peripheral
vascular and cerebrovascular disease) and 24-h mean levels of UFP (Metzger et al.  2004). The
median UF particle count in Atlanta during the study period was 25,900 particles/cm3. UFP were not
associated with CVD hospitalizations in the elderly in Copenhagen, Denmark, but were associated
with cardiac readmission or fatal MI in the European HEAPSS study (Section 6.2.10). In the
Copenhagen study, the mean count  of particles with a 100 nm mean diameter was 0.68*104
particles/cm3, whereas the PNC range was approximately  1.2-7.6*104 particles/cm3 in HEAPSS
study. Spatial variation in UFP concentration, which diminishes within a short distance from the
roadway, may introduce exposure measurement error, making it more difficult to observe an
association if one exists.
      A limited number of epidemiologic studies have evaluated subclinical cardiovascular measures
and a number of these were conducted in Boston. UFPs have been linked to ICD-recorded
arrhythmias in Boston and supraventricular ectopic beats in Erfurt, Germany (Section 6.2.2.1). One
study reported no UFP association with ectopy (Barclay et al., 2009, 179935). ST-segment
depression in subjects with stable coronary heart disease was  associated with UFPs in Helsinki
(Section 6.2.3.1). The limited number of studies that examine this size fraction makes it difficult to
draw conclusions about these cardiovascular measures.
      In summary, there is a relatively large body  of evidence from controlled human exposure
studies of fresh DE, which is typically dominated by UFPs, demonstrating effects of UFP on the
cardiovascular system. In addition,  cardiovascular effects have been demonstrated by a limited
number of laboratories in response to UF CB, urban traffic particles and CAPs. Responses include
altered vasomotor function, increased systemic oxidative stress and altered HRV parameters. Studies
using UF CAPs, as well as wood smoke and DE, provide some evidence of changes in markers of
blood coagulation, but findings are  not consistent. Toxicological studies conducted with UF  TiO2,
CB, and DE demonstrate changes in vasomotor function as well as in HRV. Effects on systemic
inflammation and  blood coagulation are less consistent. PM-dependent cardiac oxidative stress was
noted following exposure to gasoline exhaust. The few epidemiologic studies of UFPs conducted do
not provide strong support for an association of UFPs with effects on the cardiovascular system.
Based on the above findings, the evidence is suggestive of a causal relationship between
ultrafine PM exposure and cardiovascular effects.
6.3.  Respiratory Effects
6.3.1.  Respiratory Symptoms and Medication Use

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) presented evidence from epidemiologic
studies of increases in respiratory symptoms associated with PM, although this was not supported by
the findings of a limited number of controlled human exposure studies. Recent epidemiologic studies
have provided evidence of an increase in respiratory symptoms and medication use associated with
PM among asthmatic children, with less evidence of an effect in asthmatic adults. The lack of an
observed effect of PM exposure on respiratory symptoms in controlled human exposure studies does
not necessarily contradict these findings, as very few studies of controlled exposures to PM have
been conducted among groups of asthmatic or healthy children.


6.3.1.1.   Epidemiologic Studies

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) concluded that the effects of PMi0 on
respiratory symptoms in asthmatics tended to be positive, although they were somewhat less
consistent than PMi0 effects on lung function. Most studies showed increases in cough, phlegm,
December 2009                                 6-84

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difficulty breathing, and bronchodilator use, although these increases were generally not statistically
significant for PMi0. The results from one study of respiratory symptoms and PMi0_2.5 (Schwartz  and
Neas, 2000, 007625) found a statistically significant association with cough with PMi0_2.5. The
results of two studies examining respiratory symptoms and PM25 revealed slightly larger effects for
PM2.5 than for PMi0.


      Asthmatic Children

      Two large, longitudinal studies in urban areas of the U.S. investigated the effects of ambient
PM on respiratory symptoms and/or asthma medication use with similar analytic techniques (i.e.,
multistaged modeling and generalized estimating equations [GEE]): the Childhood Asthma
Management Program (CAMP) (Schildcrout et al, 2006, 089812) and the National Cooperative
Inner-City Asthma Study (NCICAS) (Mortimer et al., 2002,  030281). A number of smaller panel
studies conducted in the U.S. evaluated the effects of ambient PM concentrations on respiratory
symptoms and medication use among asthmatic children (Delfmo et al., 2002, 093740; 2003,
090941: 2003, 050460: Gent  et al., 2003, 052885: 2009, 180399: 2006, 088031: Slaughter et al.,
2003, 086294).
      In the CAMP study, the association between ambient air pollution and asthma exacerbations in
children (n = 990) from eight North American cities was investigated (Schildcrout et al., 2006,
089812). In contrast to  several past studies (Delfmo  et al., 1996, 080788:  1998, 051406). no
associations were observed between PMi0 and asthma exacerbations or medication use. PMi0
concentrations were measured on less than 50% of study days in all cities  except Seattle and
Albuquerque. While PMi0 effects were not observed  for the entire panel of children, they were
observed in recent reports on the children participating at the Seattle center (Slaughter  et al., 2003,
086294: Yu et al., 2000, 013254). In a smaller panel  study of asthmatic children (n = 133) enrolled
in the CAMP study, daily particle concentrations averaged over three central sites in Seattle was used
as the exposure metric (Slaughter  et al., 2003, 086294). Children were followed for 2 months, on
average. Daily health outcomes included both a 3-category measure of asthma severity  based on
symptom duration and frequency, and inhaled albuterol use. In single-pollutant models, an increased
risk of asthma severity  was associated with a 10 (ig/m3 increase  in lag 1 PM25 (OR 1.20 [95% CI:
1.05-1.37]) and with a 10 ug/m3 increase in lag 0 PM10 (OR 1.12 [95% CI: 1.05-1.22]). In
copollutant models with CO, the associations remained (OR for  PM2.5 1.16 [95% CI: 1.03-1.30]; OR
for PMio 1.11 [95% CI: 1.03-1.19]). Associations between inhaler use and PM were positive in
single-pollutant models (RR lag 1  PM2.5 1.08 [95% CI:  1.01-1.15]; RR lag 0 PM10 1.05 [95% CI:
1.00-1.09]), but attenuated and no longer statistically significant in copollutant models.
      The eight cities included in the NCICAS (Mortimer  et al., 2002, 030281) were all in the East
or Midwest: New York City (Bronx, E. Harlem), Baltimore, Washington DC, Cleveland, Detroit, St.
Louis, and Chicago. In  this study, 864 asthmatic children, aged 4-9 yr, were followed daily for four
2-wk periods over the course of nine months. Morning and evening asthma symptoms (analyzed as
none vs. any) and peak flow were recorded. For the three urban areas with air quality data, each
10 (ig/m3 increase in the mean of the previous 2 days (lag 1-2) PMio, increased the risk for morning
asthma symptoms (OR 1.12 [95% CI: 1.00-1.26]). This effect was robust to the inclusion of O3 (OR
1.12 [95% CI: 0.98-1.27]). In a related study, O'Connor et al. (2008, 156818) examined the
relationship between short-term fluctuations in outdoor air pollutant concentrations and changes in
pulmonary function and respiratory symptoms among children with asthma in seven U.S. inner-city
communities. PM2 5 concentration was not statistically associated with respiratory symptoms in this
study.
December 2009                                  6-85

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Study
Mar etal. (2004.057309)

Rodriguez etal. (2007, 092842)
Ranzi etal. (2004. 089500)
Aekplakorn et al. (2003, 089908)
Gent etal. (2009. 180399)
Mar etal. (2004,057309)
Rodriguez etal. (2007, 092842)
Gent etal. (2009. 180399)

OConnor et al. (2008, 156818)
Mar etal. (2004. 057309)

Rodriguez etal. (2007, 092842)
Gent etal. (2009. 180399)
Mar etal. (2004, 057309)
Aekplakorn et al. (2003, 089908)

Mar etal. (2004, 057309)
Gent etal. (2009. 180399)
Rabinovitch et al .(2006, 088031)
Slaughter etal. (2003. 086294)
Rabinovitch et al. (2004, 096753)
Slaughter et al. (2003, 086294)

Mar etal. (2004. 057309)

Aekplakorn et al. (2003, 089908)
Mar etal. (2004. 057309)



Aekplakorn et al. (2003, 089908)

Mar etal. (2004.057309)

Mar etal. (2004.057309)

Aekplakorn et al. (2003, 089908)
Just etal. (2002. 035429)
Jalaludin et al. (2004, 056595)
Mar etal. (2004. 057309)
Jalaludin etal. (2004. 056595)
Andersen et al. (2008, 096150)
Mar etal. (2004.057309)

Delfino etal. (2003. 050460)
Mortimer et al. (2002, 030281)
Rabinovitch et al. (2004, 096753)

Mar etal. (2004,057309)
Delfino etal. (2002. 093740)


Schildcroutetal. (2006, 089812)
Aekplakorn et al. (2003, 089908)

Just etal. (2002.035429)
Mar etal. (2004,057309)
Rabinovitch et al. (2004, 096753)
Jalaludin et al. (2004, 056595)
Slaughter et al. (2003, 086294)
Schildcrout et al. (2006, 089812)
Rabinovitch et al. (2004, 096753)
Just etal (2002 035429)
Slaughter etal. (2003. 086294)
ORs and 95% CIs standardized to increments of 10 (jg/m3

Location
Spokane, WA

Perth, Australia
Emilia-Romagna, Italy
Thailand
New Haven, CT
Spokane, WA
Perth, Australia
New Haven, CT

Multicity, US
Spokane, WA

Perth, Australia
New Haven, CT
Spokane, WA
Thailand

Spokane, WA
New Haven, CT
Denver, CO
Seattle, WA
Denver, CO
Seattle, WA

Spokane, WA

Thailand
Spokane, WA



Thailand

Spokane, WA

Spokane, WA

Thailand
Paris, France
Australia
Spokane, WA
Australia
Copenhagen, Den
Spokane, WA

California
Multicity, US
Denver, CO

Spokane, WA
CA, 1-hMax
CA, 8-h Max
CA 24-h Avg
US and Can
Thailand

Paris, France
Spokane, WA
Denver, CO
Australia
Seattle, WA
US and Can
Denver CO
Paris France
Seattle, WA


Lag
0
0
0-5
0-3
0
0-2
0
0-5
0-2
0-2
0-4
0
0
0-5
0-2
0
0
0
0
0-2
1
1
0-2
1

0
0
0
0
0
0
0
0
0
0

0
0
0
0-4
0-5
0
0-5
2-4
0
0
0
1-2
0-3
0-3
0
0-2
0-2
0-2
0-2
0
0
0-4
0
0-3
0-5
0
0-2
0-3
0-4
0


Endpoint
Phlegm
+ Runny Nose

Cough




Wheeze
+Shortness of Breath





Chest Tightness
Any Symptoms
+ URS
+ LRS
+ LRS
Med Use


Asthma Exacerbation


Phlegm
+ Runny Nose
Cough

Wheeze
+Shortness of Breath
Any Symptoms
+ URS
+ LRS
+ LRS

Phlegm
+ Runny Nose
Cough



Wheeze


+Shortness of Breath
Any Symptom
+ Score >1
+ Current Day

+ Previous Night





+ URS
+ LRS


+ LRS
Med U^e <Ł




s
^
Asthma Exacerbation
0.1 0.6

Effect Estimate (95% Cl)



t
0
i-«-
-0-
i A

*
—0—
— '-t —
-0!—

|


t

i — • 	
t«-
+0 —
i 	 • 	
-*-
'»
-!0-
	 + 	
— • 	
i

i — • —
-t-0 —
i 0
-i — • 	
— 10 —
-L0 —
— 10 	
1 ^ 	
—10 	
I

-p-0 	
|0-


-10-
1-0-
10-
J 	 0 	
. 1

ft
1
| *




|_ft_
1 ft

1 ft
1 Ł
^
V
'ft
1


1
-0-
*-
*

«,
i .
1 j
1.1 1.6 2.1
Odds Ratio

PM2.5























PMl 0-2.5










PMio














^ *s^













•w
r

2.6

Figure 6-7.    Respiratory symptoms and/or medication use among asthmatic children
             following acute exposure to PM.
December 2009
6-86

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Table 6-10. Characterization of ambient PM concentrations from epidemiologic studies of
respiratory morbidity and short-term exposures in asthmatic children and adults. All
concentrations are for the 24-h avg unless otherwise noted.
Study
Location
Mean Concentration
(ug/m3)
Upper Percentile
Concentrations (ug/m3)
PM2.5
Adamkiewicz et al. (2004, 0879251
Adaretal. (2007, 0014581
Aekplakorn et al. (2003, 089908)

Allen et al. (2008, 1562081
Barraza-Villarreal et al. (2008, 1562541
Bourotte et al. (2007, 150040)
de Hartog et al. (2003, 001061)
Delfino et al. (2006, 090745)
DeMeo et al. (2004, 0873461
Ebelt et al. (2005, 0569071
Ferdinands et al. (2008, 156433)
Fischer et al. (2007, 156435)
Gent et al. (2003, 0528851
Gent et al. (2009, 180399)
Girardot et al. (2006, 088271)
Hogervorst et al. (2006, 156559)
Hong et al. (2007, 0913471
Jansen et al. (2005, 0822361
Johnston et al. (2006, 091386)
Koenig et al. (2003, 156653)
Lagorio et al. (2006, 0898001
Lee et al. (2007, 0930421
Lewis etal. (2004, 097498)
Liu et al. (2009, 1920031
Mar etal. (2004, 0573091
Mar etal. (2005, 0887591
McCreanor et al. (2007, 092841)
Moshammer et al. (2006, 090771)
Murata et al. (2007, 1891591
O'Connor etal. (2008, 1568181
Steubenville, OH
St. Louis, MO
North Thailand
Seattle, WA
Mexico City
Sao Paulo, Brazil
Multicity, Europe
Southern CA
Boston, MA
Vancouver, Canada
Atlanta, GA
The Netherlands
CTSMA
New Haven, CT
Smoky Mountains
The Netherlands
Incheon City, Korea
Seattle, WA
Darwin, Australia
Seattle, WA
Rome, Italy
Seoul, South Korea
Detroit, Ml
Wndsor, Ontario
Spokane, WA
Seattle, WA
London, England
Linz, Austria
Tokyo, Japan
Multicity, U.S.
20.43
10.13

11.2
8-h max: 28.9
11.9
12.8-23.4
3.9-6.9
10.8
11.4
27.2
56
13.1
17.0
13.9
19.0
20.27
14.0
11.1
13.3
27.2
51.15
15.7-17.5
7.1
8.1-11.0
5-26
1-h avg: 11. 9-28.3
8-h avg: 15.70
39.0
14
75th: 23
98th: 51. 79
Max: 51. 79
98th: 22.43
Max: 23.24
Max: 24.8-26.3
Max: 40.38
Max: 102.8
Max: 26.6
Max: 39.8-118.1
Max: 8.8-11. 6
NR
98th: 23
Max: 28.7
Max: 34.7
75th: 187
60th: 12.1
80th: 19.0
NR
Max: 38.4
NR
Max: 36.28
Max: 44
Max: 36.5
Max: 40.4
Max: 100
75th: 87.54
Max: 92.71
Max: 56.1
95th: 19.0
98th: 19.0.
NR
NR
1-h max: 55. 9-76.1
Max 24-h avg: 76. 39
Max 1-h avg: 120
Max: 35
December 2009
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Study
Peled et al. (2005, 1560151
Penttinen et al. (2006, 0879881
Rabinovitch et al. (2004, 0967531
Rabinovitch et al. (2006, 0880311
Ranzi et al. (2004, 0895001
Rodriguez et al. (2007, 0928421
Slaughter etal. (2003,086294)
Strand et al. (2006, 089203)
Timonen et al. (2004, 087915)
Trenga et al. (2006, 1552091
von Klot et al. (2002, 0347061
Ward et al. (2002, 025839)
Location
Multicity, Israel
Helsinki, Finland
Denver, CO
Denver, CO
Emilia-Romagna, Italy
Perth, Australia
Seattle, WA
Denver, CO
Multicity, Europe
Seattle, WA
Erfurt, Germany
Birmingham and Sandwell, U.K.
Mean Concentration
(ug/m3)
23.9-29.2
8.37
10.8
10.8
Urban: 53.07
Rural: 29.11
1-havg:20.8
24-h avg: 8.5
7.3a
12.7
12.7-23.1
8.6-9.6a
30. 3b
12.3-12.7
Upper Percentile
Concentrations (ug/m3)
NR
75th: 11.15
Max: 33.53
98th: 29.3
Max: 53.5
98th: 23.4
NR
Max 1-h avg: 93.4
Max 24-h avg: 39. 4
75th: 11. 3
Max: 32.3
Max: 39.8-118.1
75th: 13.1-14.8
Max: 40. 4-41. 5
75th: 41. 3b
Max: 133.8b
Max: 28-37
PMiO-2.5
Aekplakorn et al. (2003, 089908)

Bourotte et al. (2007, 150040)
Ebelt et al. (2005, 056907)
Lagorio et al. (2006, 0898001
Mar etal. (2004, 0573091
von Klot et al. (2002, 0347061
North Thailand
Sao Paulo, Brazil
Vancouver, Canada
Rome, Italy
Spokane, WA
Erfurt, Germany
NR
21.7
5.6
15.6
8.7-13.5
10.3
NR
Max: 62.0
Max: 11.9
Max: 39.6
NR
75th: 14.6
Max: 64.3
PUn
Aekplakorn et al. (2003, 089908)

Andersen et al. (2008, 096150)
Boezen et al. (2005, 087396)
de Hartog et al. (2003, 0010611
Delfino et al. (2002, 0937401
Delfino et al. (2003, 050460)
Delfino et al. (2004, 0568971
Delfino et al. (2006, 0907451
Desqueyroux et al. (2002, 0260521
Ebelt et al. (2005, 056907)
Hong et al. (2007, 091347)
Jalaludin et al. (2004, 0565951
Jansen et al. (2005, 0822361
North Thailand
Copenhagen, Denmark
The Netherlands
Multicity, Europe
Alpine, CA
Los Angeles, CA
Alpine, CA
Southern CA
Paris, France
Vancouver, Canada
Incheon City, Korea
Sydney, Australia
Seattle, WA
31.9-37.5
25.1
26.6-44.1
19.6-36.5
20
59.9
29.7
35.7-70.8
23-28
17
35.3
22.8
18.0
Max: 113.3-153.3
75th: 30.2
Max: 89.9-242.2
Max: 67.4-112.0
90th: 32
Max: 42
90th: 86/0/Max: 126
90th: 40.9
Max: 50.7
Max: 105.5-154.1
Max: 63-84
Max: 36
Max: 124.87
75th: 122.8
Max: 51
December 2009
6-88

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Study
Johnston et al. (2006, 0913861
Just et al. (2002, 035429)
Lagorio et al. (2006, 089800)
Laurent et al. (2008, 1566721
Lee et al. (2007, 0930421
Maretal. (2004, 057309)
Mortimer etal. (2002, 030281)
Moshammer et al. (2006, 0907711
Odajima et al. (2008, 1920051
Peacock etal. (2003, 0420261
Peled et al. (2005, 156015)
Preutthipan et al. (2004, 055598)
Rabinovitch et al. (2004, 0967531
Segala et al. (2004, 0904491
Schildcrout et al. (2006, 0898121
Slaughter etal.(2003, 086294)
Steinvil et al. (2008, 1888931
von Klot et al. (2002, 0347061
Location
Darwin, Australia
Paris, France
Rome, Italy
Strasbourg, France
Seoul, South Korea
Spokane, WA
Multicity, U.S.
Linz, Austria
Fukuoka, Japan
Southern England
Multicity, Israel
Bangkok, Thailand
Denver, CO
Paris, France
Multicity, U.S.
Seattle, WA
Tel Aviv, Israel
Erfurt, Germany
Mean Concentration
(ug/m3)
20
23.5
42.8
20.8
71.40
16.8-24.5
53
8-h avg: 24.85
3-havg: 32.6-41. 5
21.2
31.0-67.1
111.0
28.1
24.2
17.7-32.43
21. Oa
64.5
45.4
Upper Percentile
Concentrations (ug/m3)
Max: 43.3
Max: 44.0
Max: 123
Max: 106.3
75th: 87.54
Max: 148.34
NR
NR
Max 24-h: 76.39
Max 3-havg: 126.0-191. 3
Max: 87.9
NR
Max: 201
Max: 102.0
Max: 97.4
75th: 26.2-42.7
90th: 32.5-53.9
75th: 29.3
75th: 60.7
75th: 59.7
Max: 172.4
3Median
Includes UFP, for complete information on number concentration from this study, please see corresponding table in Annex E.


      Mar et al. (2004, 057309) studied asthmatic children (n = 9) in Spokane, WA. Increases in 0-,
1- or 2-day lags of each of the PM size classes studied were associated with cough. When all lower
respiratory tract symptoms (wheeze, cough, shortness of breath, sputum production) were grouped
together, positive associations were reported for each 10 (ig/m3 increase in same-day PMi0 (OR 1.07
[95% CI:  1.00-1.14]), or lag 0 or lag 1 PM25 (OR 1.18 [95% CI: 1.00-1.38]; OR 1.21 [95% CI:
1.00-1.46], respectively), and 10 (ig/m3 increase in lag 0 and lag 1 PM10 (OR 1.21 [95% CI:
1.01-1.44]; OR 1.25 [95% CI: 1.01-1.55], respectively). No associations were reported for PM10_2.5
and grouped lower respiratory tract symptoms (Mar  et al., 2004, 057309).
      Gent et al. (2003, 052885) reported on daily symptom and medication use during one  summer
for 271 asthmatic children living in southern New England. In single-pollutant models  for users of
maintenance medication (n = 130), PM2.5 >19 (ig/m3 lagged by 1 day was associated with a 10-25%
increase in risk of symptoms compared to PM25 <6.9 (ig/m3: OR for persistent cough 1.12 (95% CI:
1.02-1.24); OR for chest tightness 1.21 (95% CI: 1.00-1.46); OR for shortness of breath 1.26
(95% CI:  1.02-1.54). Effects were attenuated in models including O3 (OR for persistent cough 1.00
[95% CI:  0.88-1.15]; OR for chest tightness 0.91 [95% CI: 0.71-1.17]; OR for shortness of breath
1.20 [95% CI: 0.94-1.52]). No statistical associations between ambient particle exposure and
respiratory health were found for  asthmatic children not on maintenance medication.
      Annual PM2 5 levels at monitoring sites in New Haven, CT exceed the annual standard of
15 (ig/m3. Gent et al. (2009,  180399) conducted a study here to examine the associations between
daily exposure to PM2 5 components and sources  identified through source apportionment, and daily
symptoms and medication use in asthmatic children. Asthmatic children (n = 149) aged 4-12 yr were
enrolled in the study between 2000 and 2003. Factor analysis was used to identify six sources of
PM2 5 (motor vehicle,  road dust, sulfur, biomass burning, oil, and sea salt). Total PM2 5 was not
associated with any symptoms or medication use; however trace elements originating from motor
vehicle, road dust, biomass burning and oil sources were associated with symptoms and/or
December 2009                                  6-89

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medication use. For example, an increased risk of wheeze, shortness of breath, chest tightness or
short-acting inhaler use was associated with increasing EC mass concentration. Risks remain in
models that include all six PM2.5 sources as well as NO2, which may be considered a marker for
traffic. NO2 was found to be an independent risk factor for increased wheeze.
      Two panel studies were conducted over the course of three winters at a school in Denver
(Rabinovitch  et al., 2004, 096753: 2006, 088031). In the first report, approximately 86 different
children contributed data on asthma symptoms and medication use over three consecutive winters
(Rabinovitch  et al., 2004, 096753). The exposure metric was the 3-day average concentration of
PM2 5 measured at a site located next to the school for the first two winters and from a central site
located 4.8 km (3 miles) away for the third. A strong correlation was observed during the first two
winters between PM2 5 values measured locally and at a downtown monitoring station (Pearson
product-moment correlation = 0.93) and between PMi0 values measured locally and at a downtown
monitoring station (correlation = 0.84). Therefore, in year 3, all ambient data were collected from
nearby community monitoring stations. No statistical associations were found between asthma
symptoms or medication use and PM. Rabinovitch et al. (2006,  088031) enrolled a panel of 73
children and evaluated associations with morning maximum PM2 5 measured at the central site. PM
measurements were available hourly from two co-located monitors, an FRM and a TEOM monitor.
Each 10 (ig/m3 increase in morning maximum 1-h PM25 concentration was associated with an
increased likelihood of rescue medication use (OR for FRM 1.02 [95% CI: 1.01-1.03]; OR for
TEOM 1.03 [95% CI: 1.00-1.6]). Interestingly, the association between inhaler use and particle
exposure was not evident when the 24-h avg PM2 5 was used in the model.
      Two smaller panel studies enrolling asthmatic children conducted by Delfino et al. (2002,
093740: 2003, 050460) in southern California examined the health effects  of different averaging
times for PMi0 (1-h, 8-h, 24-h) (Delfino et al., 2002,  093740). and 24-h avg of two PMio
components (EC and OC) (Delfino  et al., 2003, 050460). In the first study, 22 children living in a
"lower" pollution area were followed daily for two months in spring.  In contrast with Gent et al.
(2003, 052885). positive statistical associations with asthma symptoms (measured on a 6-point
severity scale) were found only for the  children not taking anti-inflammatory medication. For these
12 children, in single-pollutant models  each 10 (ig/m3 increase in lag 0 1-h max PMio nearly doubled
the risk of clinically meaningful symptoms (i.e., an asthma symptom score >3)  (OR 1.14 [95% CI:
1.04-1.24]) and each  10  ug/m3 increase in 3-day avg 24-h PM10 increased the risk by 1.25 (95% CI:
1.06-1.48). No statistical associations were found between exposure to ambient particles and
symptoms in the ten children who were taking anti-inflammatory medication. No multipollutant
models were reported. The second study enrolled 22 asthmatic children living in an area of higher
pollution.  For children living in this community, each 10 (ig/m3 increase in lag 0, 24-h PMio was
associated with  an increased risk of asthma symptom score >1: OR 1.10, (95%  CI: 1.03-1.19)
(Delfino et al., 2003, 050460). The correlation among PM10, EC and OC was substantial: 0.80
between PMio and either EC or OC, and 0.94 between EC and OC. Associations between EC or OC
and asthma symptoms were very similar to those for PMi0: each 3 (ig/m3 increase in lag 0, 24-h EC
or 5 (ig/m3 increase in lag 0, 24-h OC was associated with an increased risk of asthma symptoms
(OR 1.85 [95%  CI: 1.11-3.08] or OR 1.88 [95% CI: 1.12-3.17], respectively) (Delfino  et al., 2003,
050460).
      The association between incident wheezing symptoms and air pollution was assessed in the
Copenhagen Prospective Study of Asthma in Children among a birth cohort of 205 children in
Copenhagen, Denmark.  In addition to  PMio  and other gaseous air pollutants, the study examined
UFP concentrations collected from a central background monitoring station. This is the only study
identified that examined the association between UFPs and respiratory symptoms in children. There
were strong adverse effects for PMio and UFPs, as well as for NO2, NOX, and CO for wheezing
symptoms in infants which attenuated after the age of 1 yr (lag 2-4 PM10 OR 1.21 (95% CI 0.99-
1.48); lag 2-4 UFP OR 1.92 (95% CI: 0.98-3.76)). These associations remained in copollutant
models including NO2, NOX and CO.
      Studies from Australia (Rodriguez  et al., 2007, 092842).  Europe (Andersen et al., 2008,
096150: Laurent et al., 2008, 156672:  Laurent et al., 2009,  192129: Ranzi et al., 2004, 089500).
and Asia (Aekplakorn et al., 2003, 089908) provide additional evidence of an association between
ambient PM and respiratory symptoms and/or medication use among asthmatic children. Two studies
(Jalaludin  et al., 2004, 056595; Just  et al., 2002, 035429) found no association between ambient PM
levels and these health endpoints.
December 2009                                 6-90

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      Asthmatic Adults

      Since the 2004 PM AQCD (U.S. EPA, 2004, 056905). one U.S. and several European studies
have investigated the effects of ambient PM levels on respiratory symptoms and medication use
among asthmatic adults. The respiratory symptom and medication use results from these studies are
summarized by particle size and displayed in Table 6-10 and Figure 6-8. Relatively few studies
examined these effects in healthy adults, and they did not identify a relationship between ambient
PM levels and respiratory symptoms or medication use. These studies of healthy adults are
summarized in Annex E, but will not be described in detail in this section.
      Mar et al. (2004,  057309) studied asthmatic adults (n = 16) in Spokane, WA over a 3-yr time
period. No associations were found between PM and respiratory symptoms among the adults.
      Several panel studies conducted in Europe have examined effects of daily exposures to air
pollution on adults with asthma, including studies in the Pollution Effects on Asthmatic  Children in
Europe (PEACE) study (Boezen et al., 2005, 087396). Exposure and Risk Assessment for Fine and
UFPs in Ambient Air (ULTRA) study (De et al., 2003, 001061). in Germany (Von  et al., 2002,
034706). and in Paris (Desqueyroux et al., 2002, 026052: 2004, 090449). Boezen et al.  (2005,
087396) enrolled 327 elderly adults in the Netherlands to examine the role of airway
hyperresponsiveness (AHR) and IgE levels in susceptibility to air pollution. For subjects with both
AHR (defined as > 20% FEVi decline at < 2 mg cumulative methacholine [Mch]) and high total IgE
(>20 kU/L), each 10 (ig/m3 increase in lag 2 PMi0 concentration was associated with an increased
risk of upper respiratory symptoms (URS) among males (OR 1.06 [95% CI: 1.02-1.10]), and at lag 0
with increased cough among females (OR 1.04 [95% CI: 1.00-1.08]). Each 10 (ig/m3 increase in BS
at lag 0, lag 1,  and the 5-day mean was associated with URS and cough among males. The strongest
association in both cases was for the 5-day mean (OR for URS 1.43 [95% CI:  1.20-1.69]; OR for
cough 1.16 [95% CI: 1.05-1.29]). The authors suggest that the sex differences observed  may be
explained by differential daily exposure to traffic exhaust experienced by men compared to women
(Boezen  et al.. 2005. 087396).
      As part of the multicenter ULTRA study, de Hartog et al. (2003, 001061) enrolled 131 older
adults with coronary artery disease in three cities (Amsterdam, Erfurt [Germany], and Helsinki).
Pooling data from all 3  cities, associations were observed between PM2.5 and shortness of breath and
phlegm: each 10 ug/m3  increase in the 5-day avg PM25 was associated with an increased risk of
symptoms (OR for shortness of breath 1.12 [95% CI: 1.02-1.24]; OR for phlegm 1.16 [95% CI:
1.03-1.32]). Unlike fine particles, UFPs were not consistently associated with symptoms.
      In a study that took place in  Erfurt, Germany, von Klot et al. (2002, 034706) examined daily,
winter time exposure to ambient PM10_2.5, PM2.5_0.oi and PM0.i_0.oi and respiratory health effects in 53
adult asthmatics. The authors examined associations between wheeze, use of inhaled, short-acting
p2-agonists or inhaled corticosteroids and exposure to particles in single and multipollutant models.
Particle exposure metrics examined included same-day, 5-day and 14-day average concentrations.
No effects were observed for wheeze and exposure to PMi0_2.5 for any averaging time. The strongest
association between wheeze and exposure to UFPs was for a 14-day avg: each 7,700 increase in the
NCooi-o i increased the risk of wheeze by 27% (OR 1.27 [95% CI: 1.13-1.43]). The effect was
attenuated in copollutant models that also included PM25 001 (OR 1.12 [95% CI: 1.01-1.24]), NO2
(OR 1.12 [95% CI: 0.99-1.26]), CO (OR 1.05 [95% CI: 0.92-1.19])  or SO2 (OR 1.14 [95% CI:
1.04-1.26]). The correlations between UFPs and two gaseous pollutants, NO2 and CO, were high:
0.66 for each.
December 2009                                 6-91

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Study
Location     Lag   Endpoint
Effect Estimate (95% Cl)
de Hartog et al. (2003,001061)   Netherlands
Mar et al. (2004,057309)       Spokane, WA
de Hartog et al. (2003,001061)   Netherlands
Mar et al. (2004,057309)       Spokane, WA

Johnston et al. (2006,091386)    Australia
Mar et al. (2004,057309)       Spokane, WA
Mar et al. (2004,057309)       Spokane, WA

von Klotetal. (2002.034706)    Germany
Mar et al. (2004,057309)       Spokane, WA
von Klotetal. (2002.034706)    Germany
Mar et al. (2004,057309)       Spokane, WA

Mar et al. (2004,057309)       Spokane, WA

Boezen et al. (2005,087396)    Netherlands
Segala et al. (2004,090449)     Paris, France
Mar et al. (2004,057309)       Spokane, WA
Desqueyroux et al. (2002,026052) Paris, France
Johnston et al. (2006,091386)    Australia
Mar et al. (2004,057309)       Spokane, WA
Boezen et al. (2005,087396)     Netherlands
Mar et al. (2004,057309)       Spokane, WA
           0-4  Phlegm
            0
            0      + Runny Nose
            0  Cough
           0-4  Wheeze
            0  Shortness of breath
            0
           0-5  Asthma Symptoms
            0
            0      +LRS

            0  Phlegm
            0      + Runny Nose
           0-4  Wheeze
            0
            0  Shortness of breath
            0  Cough
            0  Any Symptom
           0-4  Medication Use
            0  Asthma Symptoms

            0  Phlegm
            0      + Runny Nose
           0-4  Cough
            0
            0
            0  Wheeze
            0  Shortness of breath
           3-5  Asthma Symptoms
           0-5
            0
           0-4      + URS
            0      +LRS
                                PMZ5
         1 •
                                                                                            PM«
                                PM«
                                                     0.50    0.75    1.00     1.25

                                                                  Odds Ratio
                                                              1.50
                               1.75
Figure 6-8.    Respiratory symptoms and/or medication use among asthmatic adults following
               acute exposure to particles.  Summary of studies using 24-h avg of PMio, PM2.5,
               PMio-2.6- ORs and 95% CIs were standardized to increments of 10 ug/m3.

      In the same study, no association was found between exposure to PMi0_2.5,, PM2 5, or UFPs and
use of short-acting inhalers, though there was an association with maintenance medication. Increased
likelihood of maintenance medication was significantly associated with PM of all sizes and all
averaging times (same-day, 5- and 14-day avg) and gaseous copollutants in single or copollutant
models. The strongest effects were seen for 14-day avg of PMi0_25 (for each 10 ug/m3 increase OR
1.43 [95% CI: 1.28-1.60]), PM25.001 (for  each 20 ug/m3 increase OR 1.54 [95% CI: 1.43-1.66]),
NCo.oi-o.1 (for each 7,700 increase OR 1.45 [95% CI: 1.29-1.63]). For PM2.5.0.0i, effects were
unchanged in copollutant models, including a model with UFPs. The authors conclude that this is
evidence for independent effects of PM2.5 and UFPs (Von et al., 2002, 034706).
      In Paris, Segala et al. (2004, 090449) recruited 78 adults from an otolaryngology clinic  and
followed them for three months. Both PM10 and BS (which were highly correlated [r =.88]) were
associated with cough: OR 1.24 (95% CI: 1.01-1.52) for a 10  ug/m  increase in mean 0-4 day PMi0
and OR 1.18 (95% CI: 1.02-1.39) for a 10 ug/m3 increase in BS.
      Also in Paris, 60 severe asthmatics were followed for 13 months and the relationship between
daily air quality (including 24-h PMi0 as measured at the site nearest to the subject's home) and
asthma attack (defined as the need to increase rescue medication use and one or more positive signs
on clinical exam of wheezing, expiratory brake, thoracic distention, hypertension with tachycardia,
polypnea) were examined with GEE models (Desqueyroux  et al., 2002, 026052). Each 10 ug/m3
increase in PMi0 increased the risk of asthma attack, but only  after lags of 3-5  days. The strongest
effect was seen for the mean lag of days 3-5 (OR 1.21  [95% CI: 1.04-1.40]). Effect sizes were larger
among patients not on regular oral steroid therapy: for PMi0 lag 3-5  (OR 1.41  [95% CI: 1.15-1.73]).
This effect persisted  in copollutant models for winter time levels of PMi0 and SO2 (OR 1.51 [95%
December 2009
                         6-92

-------
CI: 1.20-1.90]) or NO2 (OR 1.43 [95% CI: 1.16-1.76]), but not in summer time models with O3 (OR
1.09 [95% CI: 0.71-1.67]).


      Copollutant Models

      A limited number of respiratory symptoms studies reported results of copollutant models.
Generally, the associations between respiratory symptoms and PM were robust to the inclusion of
copollutants (Figure 6-9), though Desqueyroux et al. (2002, 026052) indicate the effects of PM may
be potentiated by NO2 and SO2 during the winter months. Gent et al. (2003, 052885) also reported
the results of copollutant models, though the categorical  exposure groups used in the analysis did not
allow these  results to be included in Figure 6-9. As reported above, the investigators found that
effects were attenuated in models including O3.
Study
Outcome
Pollutant
Effect Estimate (95% CI)
Slaughter et al. (2003,086294)

Aekplakorn et al. (2003,089909)
Asthma Severity

Cough
Aekplakorn et al. (2003,089909)   Cough
PM25
PM25+CO
PM25
PM2.5+S02

PM1(>2.5
PM10.2.5+S02
Slaughter et al. (2003,086294)

Mortimer et al. (2002,030281)

Aekplakorn et al. (2003,089909)

Andersen et al. (2008,096150)
Asthma Severity     PMm
               PMm+CO
AM Asthma Symptoms PM10
               PM10+03
Cough           PM10
               PM10+S02
Wheeze          PM10
               PM10+N02
               PMm+CO
Andersen et al. (2008,096150)    Wheeze
Desqueyroux et al. (2002,026052) Asthma Attack
               UFP
               UFP+ PM10
               UFP+ N02
               UFP+CO

               PM10
               PM10+N02
               PM10+03
               PM10+S02
                                                 I
                                                0.5
                  PM2.5 Asthmatic Children
                                                                                 PMi0-2.5 Asthmatic Children
                                                                                  PMio Asthmatic Children
                                                                                  UFP Asthmatic Children
                                                                                   PMio Asthmatic Adults
                                     \           I            I
                                     1.0         1.5         2.0
                                              Odds Ratio
                                                                                             2,5
Figure 6-9.    Respiratory symptoms following acute exposure to particles and additional
               criteria pollutants. Circles represent single pollutant effect estimates and
               squares represent copollutant effect estimates.
6.3.1.2.   Controlled Human Exposure Studies
      CAPs

      Neither new controlled human exposure studies nor studies cited in the 2004 PM AQCD
(U.S. EPA, 2004, 056905) have found significant effects of CAPs on respiratory symptoms among
healthy or asthmatic adults, or among older adults with COPD (Gong et al., 2000, 155799; 2003,
042106; 2004, 087964; 2004, 055628; 2005, 087921; 2008, 156483; Petrovic  et al., 2000, 004638).
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      Urban Traffic Particles

      One new study reported an increase in respiratory symptoms (upper and lower airways) among
healthy volunteers (19-59 yr) during a 2-h exposure to road tunnel traffic (PM25 concentration 46-
81 ug/m3) (Larsson et al., 2007, 091375). However, information on specific respiratory symptoms
(e.g., throat irritation, wheeze or chest tightness) was not provided. In addition, this study only
evaluated respiratory symptoms pre- versus post-exposure, and did not compare response with a
filtered air control exposure.


      Diesel Exhaust

      Respiratory symptoms including mild nose and throat irritation have been reported following
controlled exposure to DE; however, other symptoms such as cough, wheeze and chest tightness
have not been observed (Mudway et al., 2004, 180208).


      Model Particles

      Pietropaoli et al. (2004, 156025) found no association between exposure to UF carbon
particles and respiratory symptoms in healthy adults at concentrations between  10 and 50 ug/m3, or
asthmatics at a concentration of 10 ug/m3. Beckett et al. (2005, 156261) exposed healthy subjects to
UF and fine ZnO (500 ug/m3) and observed no difference in respiratory symptoms compared to
filtered air control 24 h following exposure. In a study evaluating respiratory effects of exposure to
ammonium bisulfate or aerosolized H2SO4 (200 and 2,000 ug/m  ) among healthy and asthmatic
adults, Tunnicliffe et al. (2003, 088744) observed no change in respiratory symptoms with either
particle type or concentration relative to filtered air. This finding is in agreement with many similar
older studies which have generally reported no increase in respiratory symptoms following exposure
to acid aerosols at concentrations <1,000 ug/m3 (U.S. EPA, 1996, 079380; 2004, 056905).


      Summary of Controlled Human Exposure Study Findings for Respiratory
      Symptoms

      These new studies  confirm previous reports that have found no association between PM
exposure and respiratory  symptoms.


6.3.2.   Pulmonary  Function

      Epidemiologic studies cited in the 2004 PM AQCD (U.S. EPA, 2004, 056905) observed small
decrements in pulmonary function associated with both PM25 and PMi0 (U.S. EPA, 2004, 056905).
The majority of controlled human exposure studies reported no effect of PM on pulmonary function,
while the results from toxicological studies were mixed, with some evidence of changes in tidal
volume and respiratory rate following exposure to CAPs. Epidemiologic studies published since the
2004 PM AQCD  (U.S. EPA, 2004, 056905) have reported an association between PM2.5
concentration and decrements in forced expiratory volume in one second (FEVi), particularly among
asthmatic children. These findings are coherent with recent toxicological evidence of AHR
following CAPs exposure. Results from recent controlled human exposure studies have been
inconsistent, with some studies demonstrating small decreases in arterial oxygen saturation, FEVi or
maximal  mid-expiratory flow following exposure to CAPs or EC. It is interesting to note that these
effects appear to be more pronounced among healthy adults than adults with asthma or COPD. A
number of recent animal toxicological studies demonstrated  alterations in respiratory frequency
following short-term exposure to CAPs.
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6.3.2.1.   Epidemiologic Studies

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) concluded that both PM2.5 and PMi0 appeared
to affect lung function in asthmatics. A limited number of studies evaluated UFPs and found them to
be associated with a decrease in peak expiratory flow (PEF). Few analyses were able to clearly
distinguish the effects of PM2.5 and PMi0 from other pollutants. Results for PMi0 PEF analyses in
non-asthmatic studies were inconsistent, with fewer studies reporting strong associations.


      Asthmatic Children

      Several recent panel studies have been conducted in the U.S. examining the association of
exposure to ambient PM and lung function in asthmatic children (Allen et al., 2008, 156208 in
Seattle; Lewis et al.,  2003, 088413 in Southern California; 2004, 097498: Lewis et al., 2005,
081079 in Detroit; O'Connor et al., 2008, 156818: Rabinovitch  et al., 2004, 096753 in Denver).
Mean concentration data from these studies are summarized in Table 6-10. In the Inner-City Asthma
Study (ICAS), FEVi and PEF tidal were statistically related to the 5-day avg of PM2.5 but not to the
1-day avg concentration (O'Connor et al., 2008, 156818). The risk of experiencing a percent-
predicted FEVi more than 10% below personal best was related to the 5-day avg concentration of
PM25 (1.14 [95% CI:  1.01-1.29]). The risk of experiencing a percent-predicted PEF rate more than
10% below personal best was related to PM2.5 (1.18  [95% CI: 1.03-1.35]). This effect remained
robust in copollutant models with O3 and NO2 for the FEVi effect, but not the PEF rate effect.
      The Denver study (Rabinovitch et al., 2004, 096753), described in  Section 6.3.1.1, also
examined daily FEVi and PEF in 86 asthmatic children over the course of three  winters (some
subjects participated in more than one winter). Lung function measurements were performed under
supervision daily at the elementary school where all subjects attended, and without supervision every
evening and on nonschool days. As described above, the authors chose to  use a 3-day moving
average of 24-h PM25 or PMi0 as the exposure metric. No statistical associations were observed
between morning or afternoon FEVi or PEF and particle exposure. The same group of researchers
(Strand et al., 2006, 089203) used regression calibration to estimate personal exposures to ambient
PM2.5 and found that a 10 (ig/m3 increase in PM2.5 was associated with a 2.2% (95% CI: 0.0-4.3)
decrease in FEVi at a 1-day lag as compared with the estimate of a 1.0% decrease in FEVi using
ambient PM25 concentrations from fixed monitors. These results underscore the effects of exposure
error on epidemiologic study results; the effect estimate using an estimate of personal exposure to
ambient PM2 5 was twice that for  central site PM2 5.
      From winter 2001 to the spring of 2002, the same number (n = 86)  of primary school-age
asthmatic children participated in six 2-wk seasonal  assessments of lung function in Detroit (Lewis
et al., 2005, 081079).  Using a protocol similar to that used in Rabinovitch et al. (2004, 096753).
morning lung function measurements (FEVi, PEF) were self-administered at school under
supervision by research staff. Evening and weekend measurements were recorded by subjects at
home, without supervision from research staff. Community-level exposure was assessed using
monitors placed on a  school rooftop of both of the communities. Most of the subjects (82 of 86)
lived within 5 km of their respective community monitors. In single-pollutant models using GEE and
only among children reporting the use of maintenance medication (corticosteroids), each 10 (ig/m3
increase in lag 2 PMi0 was associated with a decrease in the lowest daily percent predicted FEVi (a
reduction of 1.15%, [95% CI: -2.1 to -0.25]). Among children reporting presence of URI on the day
of lung function measurement, increases in the average of lag 3-5 of either PM25 or PMi0 resulted in
a decrease in the lowest daily FEVi (for a 10 (ig/m3 increase in PM25 the  reduction was 2.24% [95%
CI; -4.4 to -0.25]; and for a 10 ug/m3 increase in PMi0 the reduction was 2.4% [95% CI: -4.5 to
-0.3]). In copollutant  models that included one particle pollutant and O3, and among children using
maintenance medication, lag 3-5 PM25 continued to be associated with lowest daily FEVi as well as
diurnal FEVi variability: each 10 (ig/m3 increase was associated with a 2.23% decrease in FEVi
(95% CI: -3.92 to -0.57) and a 2.22% increase in FEVi variability (95% CI: 1.0 to 3.50). Increases in
lag 1 or lag 2 of PMi0 were associated with FEVi and FEVi diurnal variability in copollutant models.
The strongest association was with lag 2 for diurnal variability (for each 10 (ig/m3 increase
variability increased by 7.0% [95% CI: 4.2-9.6). It is unclear what role the lack of supervision during
the evening and weekend measures may have had on these diurnal results.
      Two panel studies in southern California examined the association of PM  exposure on lung
function in asthmatic  children (Delfino et al., 2003, 050460: 2004, 056897). In Delfino et al. (2003,
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050460). described above, no association between exposure to particles and PEF was found for 22
Hispanic, asthmatic children living in an area of relatively high pollution. In Delfino et al. (2004,
056897)  19 asthmatic children, aged 9-17 yr, were followed for 2 weeks and daily, self-administered
FEVi measurements were taken. Particle exposures studied included central-site PMi0 in addition to
personal  PM (in the range of 0.1-10 (im range, with the highest response in the fine PM range), and
home stationary measurements of both PM2.5 and PMi0. The authors report inverse associations
between percent expected FEVi and PM indicators. The strongest association for exposure to
personal  PM was for a 5-day moving average of 12-h daytime PM: for each 10 (ig/m3 increase, FEVi
decreased by 7.1% (95% CI: -9.9 to -2.9). Effects for all stationary sites (inside and outside of
residence, central site) for PM2.5 were on the order of 1-2% reductions in FEVi, with the strongest
associations for the 5-day moving average (presented in figures only). Likewise for PMi0 measured
at stationary sites, the strongest effects were for the 5-day moving average and ranged from
approximately 3.8% reduction associated with indoor monitors to about 1.5% for both the outdoor
and central site monitors (presented in figures only). A helpful comparison among all 24-h measures
is given for 10 (ig/m3 increases in personal PM and PM2.5 associated with decreases in percent
predicted FEVi: an increase of 10 (ig/m3 personal PM is associated with a decrease in FEVi of 3.0%
(95% CI: -5.6 to -0.5); 10 (ig/m3 increase in indoor PM with 2.4% decrease (95%  CI: -4.2 to -0.6);
10 (ig/m3 increase in outdoor PM with 1.5% decrease (95% CI: -3.4 to 0.1); 10 ug/m3 increase in
central site PM with 0.9% decrease (95% CI: -2.6 to 0.5).
      Trenga et al. (2006, 155209) reported associations among personal, residential, and central site
PM2.5 and lung function in 17 asthmatic children in Seattle. The only statistical association with
decline in FEVi was with indoor measurements of PM25: each 10 (ig/m3 increase in lag 1 indoor
PM2.5 was associated with a decline in FEVi of 64.8 mL (95% CI: -111.3 to 18.3) (a 3.4% decline
from the  mean of 1.9 L). Indoor PM25 (lag  1) was also associated with declines in PEF (by 9.2 L/min
[95% CI: -17.5 to  -0.9], a 3.6% decline from the 254 L/min avg) and in maximal mid-expiratory
flow (MMEF) for the six  subjects not taking anti-inflammatory medication (by 12.6 L/min [95% CI:
-20.7 to -4.6], a 13.7% decline from the 92 L/min avg). Personal PM25 (lag 1) was only statistically
associated with PEF for the six subjects not on anti-inflammatory medication: each 10 (ig/m3
increase resulted in a 10.5 L/min  ([95% CI: -18.7 to -2.3], a 4.5% decline from the 233 L/min avg)
reduction in PEF. Anti-inflammatory medication use attenuated associations with PM2 5.
      Also in Seattle, Allen et al.  (2008, 156208) evaluated the effect of different PM2 5 exposure
metrics in relation to lung function among children in wood smoke-impacted areas. The authors
found that the ambient-generated component of PM25 exposure was associated with decrements in
lung function only among children not using inhaled corticosteroids, whereas no association was
reported with the nonambient exposure component. All of the ambient concentrations were
associated with decrements in both PEF and maximal expiratory flow (MEF). There were no
associations between any  exposure metrics  and forced vital capacity  (FVC). The authors suggest that
lung function may be especially sensitive to the combustion-generated component of ambient PM2 5,
whereas airway inflammation may be more closely related to some other source.
      In a longitudinal study, Liu et al. (2009,  192003) examined the association between acute
increases in ambient air pollutants and pulmonary function among children (ages 9-14 yr) with
asthma. FEVi and FEF25_75o/0 exhibited a consistent trend of negative associations with PM25 across
lag days 0,  1, 0-1, and 0-2, with the strongest effects for FEF25.75o/0 on lag day 0 (-1.12% [95% CI:
-2.06 to -0.18]) and lag days 0-1 (-1.18% [95% CI: -2.24 to -0.12]). Copollutant models including
O3, SO2 or NO2 did not result in marked changes in the PM2 5 risk estimates for FEVi or FEF25_75o/0.
      Moshammer and Neuberger (2003, 041956) used a novel technique for assessing exposure to
PM in a study they conducted in Austria. They employed a diffusion charging particle sensor (model
LQ 1-DC, Matter Engineering AG, Wohlen, Switzerland) and a photoelectric aerosol sensor (model
PAS 2000 CE, EcoChem Analytics, League City, TX) to relate the spirometry scores of Upper
Austrian  children, aged 7-10 yr, to particle surface area and particle-bound PAH concentration,
respectively. Details on these methods for measuring surface area and PAH can be found in Shi et al.
(2001, 078292) and Burtscher (2005, 155710). respectively. By measuring the surface area
distribution, it was possible to understand potential for contact area with respiratory tract cells. The
authors found that acute decrements of pulmonary function (FVC, FEVi, MEF50) were related to the
active surface of particles after adjustment for PMi0. For short-term lung impairments, this indicates
that active particle surface is a better index of exposure than PM mass.
      A number of additional panel studies conducted outside of the  U.S. and Canada also examined
lung function using more  traditional exposure metrics. Several European and Asian studies reported
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associations with PM measurements and decrements in pulmonary function (FEVi, FVC, FEF, MEF,
PEF rate) (Hogervorst et al., 2006, 156559; Hong et al., 2007, 091347; Moshammer et al, 2006,
090771; Odajima et al., 2008, 192005; Peacock  et al., 2003, 042026; Peled et al., 2005, 156015).
Others found little evidence for a relationship between PM and daily changes in PEF after correction
for the confounding effects of weather, trends in the data, and autocorrelation (Fischer et al., 2002,
025731; Holguin et al., 2007, 099000; Just et al., 2002, 035429; Preutthipan et al., 2004, 055598;
Ranzi  et al., 2004, 089500; Ward,  2003, 157111).


      Adults

      Trenga et al.  (2006, 155209) examined personal, residential, and central site monitoring of
particles and the relationship with  lung function in Seattle.  In models controlling for gaseous
copollutants (CO, NO2), adults, regardless of COPD status, experienced a decline in FEVi associated
only with measurements of PM2.5 at the  central site: each 10 ug/m3 increase in lag 0 PM2.5 was
associated with a 35.3 mL (95% CI: -70 to -1.0) decrease in FEVi. This represents a 2.2% decline in
mean  FEVi (mean  1.6 L during the study). Results for personal, indoor and outdoor measures of
PM2.5  were inconsistent. No statistical associations were reported with outdoor PMi0_2.5.
      Girardot et al. (2006, 088271) assessed the effects of PM25 on the pulmonary function of adult
day hikers in the Great Smoky Mountains National Park. Hikers performed spirometry both before
their hike and when they returned from their hike. The authors reported no statistically significant
responses in pulmonary function with an average of five hours of outdoor exercise at ambient PM25
levels that were below the current NAAQS. Specifically, post-hike percentage changes in FVC,
FEVi, FEVi/FVC, FEF25_75, and PEF were not associated with PM25 exposure.
      Ebelt et al. (2005, 056907) developed an approach to separately estimate exposures to PM of
ambient and non-ambient origin based on a mass balance model. These exposures were linked with
respiratory and cardiovascular health endpoints for 16 patients with COPD in Vancouver, Canada
(mean age 74 yr). Effect estimates  for estimated ambient exposure were generally equal to or larger
than those for the respective ambient concentration levels for post-FEV and AFEVi, and were
statistically significant for all AFEVi comparisons (estimated from figure).
      Several studies outside of the U.S. and Canada examined the relationship between PM
concentrations and lung function and all reported a decrease in lung function in adults (FEVi, FVC,
PEFR) associated with PM exposure (Boezen  et al., 2005,  087396; Bourotte et al., 2007,  150040;
Lagorio et al., 2006,  089800; Lee  et al., 2007, 093042; McCreanor  et al., 2007, 092841;  Penttinen
etal,  2006, 087988).

      Measures of Oxygen Saturation

      Oxygen  saturation measures the percentage of hemoglobin binding sites in the bloodstream
occupied by oxygen. DeMeo et al.  (2004, 087346) estimated the change in oxygen saturation and
mean  PM25 concentration in the previous 24 h in a panel of elderly subjects. They used the same
panel  of elderly Boston residents (n = 28) and study protocol and analytic methods  (12 wk of
repeated oxygen saturation measurements) as  Gold et al. (2005, 087558) and Schwartz et al. (2005,
074317) in studies of ST-segment depression and HRV, respectively. At each clinic  visit, subjects had
5 min each of rest,  standing, post-exercise rest, and 20 cycles of paced breathing. The median PM25
concentration during the study period was  10.0 (ig/m3 (Schwartz et al., 2005, 074317). Each
10 (ig/m3 increase in the mean PM25 concentration in the previous 6 h was associated with a 0.15%
decrease in oxygen saturation (95% CI:  -0.22 to 0.0) during the baseline rest period. Each  10 (ig/m3
increase in mean 6-h PM2 5 concentration was also associated with a decline in oxygen saturation
during the post-exercise period (-0.15%  [95% CI: -0.22 to 0.0]), and post-exercise paced breathing
period (-0.07% [95% CI: -0.22 to 0.0]), but not during the exercise period.  The authors suggest that
these  oxygen saturation reductions may  result from pulmonary vascular and inflammatory changes.
      In a similar study, Goldberg  et al.  (2008, 180380) examined the association between oxygen
saturation, pulse rate, and ambient PM25, NO2, and SO2 concentrations in a panel of 31 subjects in
Montreal, with NYHA Class II or III heart failure who were aged 50-85 yr. Although each 10 (ig/m3
increase in PM25 on lag day 0 was associated with a -0.119 (95% CI = -0.196 to -0.042) change in
oxygen saturation in unadjusted models, once adjusted for temperature and barometric pressure, the
estimated change was smaller and  no longer significant (-0.077 [95% CI = -0.160 to 0.007). Only
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SO2 was significantly associated with reduced oxygen saturation in copollutant models. None of the
pollutants examined, including PM2.5, were associated with a change in pulse rate.


6.3.2.2.   Controlled Human Exposure Studies

      As with respiratory symptoms, there is little evidence from controlled human exposure studies
of PM-induced changes in pulmonary function. One study cited in the 2004 PM AQCD (U.S. EPA,
2004, 056905) noted a significant decrement in thoracic gas volume in healthy adults following a 2-h
exposure to PM2.5 CAPs (92 ug/m3); however, no significant changes were observed in spirometric
measurements, diffusing capacity (DLCO), total lung capacity, or airways resistance (Petrovic et al.,
2000, 004638). Other studies found no significant changes in pulmonary function in healthy adults
following exposure to inhaled iron oxide particles (Lay et al., 2001,  020613) or UF EC (Frampton,
2001, 019051). or in healthy and asthmatic adults following exposure to CAPs (Ohio et al., 2000,
012140; Gong et al., 2000, 155799; 2003, 087365). Rudell et al. (1996, 056577) reported a
significant increase in specific airways resistance following exposure to DE, an effect that was not
attenuated by reducing the particle number by 46% (2.6xlO6particles/cm3 compared with 1.4xl06
particles/cm ) using a particle trap. The particle trap did not affect the concentrations of other
measured diesel emissions including NO2, NO, CO, or total hydrocarbons. As described below, more
recent controlled human exposure studies provide limited and inconsistent evidence  of changes in
lung function following exposure to particles from various sources.


      CAPs

      Among a group of healthy and asthmatic adults exposed to UFPs (Los Angeles, mean
concentration 100 ug/m3), Gong et al. (2008, 156483) observed small, yet statistically significant
decrements in arterial oxygen saturation immediately following exposure, 4 h post-exposure, and
22 h post-exposure (0.5% mean decrease relative to filtered air across all time points, p < 0.05). A
statistically significant decrease in FEVi was also  observed, but only at 22 h post-exposure (2%
decrease relative to filtered air, p < 0.05). The responses demonstrated in this study were not affected
by health status. No such effects were observed in a similar study conducted in Chapel Hill, NC
which exposed healthy adults to a lower concentration of UF  CAPs (49.8 ug/m3) (Samet et al.,
2009, 191913). In addition, two studies evaluating effects of exposure to PMi0_2.5 CAPs (average
concentration 89-157 ug/m3) on lung function observed no changes in spirometric measurements,
DLCO or arterial oxygen saturation 0-22 h post-exposure in asthmatic or healthy adults (Gong et al.,
2004, 055628: Graff et al., 2009, 191981). While Gong et al. (2004,  087964) did not observe a
significant association between exposure to PM25  CAPs and spirometry in older subjects (60-80 yr),
the investigators did report a decrease in oxygen saturation immediately following CAPs exposure.
This effect was observed more consistently in healthy older adults than in older adults with COPD.
These findings were confirmed by a subsequent study conducted by the same laboratory (Gong et
al., 2005, 087921). The authors also observed a small decrease in MMEF following a 2-h exposure
to PM2 5 CAPs (200 ug/m3) which was more pronounced in healthy subjects.


      Urban Traffic Particles

      Neither short-term exposure to relatively high levels of urban traffic particles nor longer
exposures to lower concentrations of urban particles have been observed to alter pulmonary function
in controlled exposures among healthy adults. Larsson et al. (2007, 091375) exposed 16 adults for
2 h to PM25 concentrations of 46-81 ug/m3 in a room adjacent to a busy road tunnel, with
concomitant exposure to NO2(0.12 ppm), NO (0.71 ppm), and CO (5 ppm). Although respiratory
effects in this study were not compared to filtered  air control, no difference in lung function was
observed 14 h after exposure to traffic particles relative to lung function measured on a day
following typical activities that did not include transit though a road tunnel. In a study of 24-h
exposures to urban traffic particles (PM25 9.7 ug/m3), no change in lung function was reported at
2.5 h after the start of exposure relative to filtered air (Brauner et al., 2009, 190244).
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      Diesel Exhaust

      Mudway et al. (2004  180208) exposed 25 healthy adults to DE with an average particle
concentration of 100 ug/m and observed mild bronchoconstriction (airways resistance) immediately
following exposure relative to filtered air. No changes were observed in FEVi or FVC following DE
exposure in these subjects, or in a group of 15 asthmatics exposed using the same protocol (Mudway
et al., 2004, 180208; Stenfors  et al., 2004, 157009).


      Model Particles

      Pietropaoli et al. (2004,  156025) observed a reduction in MMEF and DLCO in healthy adults
21 h after a 2-h exposure to UF carbon particles (50 ug/m3). This reduction in DLCO may reflect a
PM-induced vasoconstrictive effect on the pulmonary vasculature. Tunnicliffe et al. (2003, 088744)
did not observe any significant change in lung function following exposure to ammonium bisulfate
or aerosolized H2SO4 (200 and 2,000 ug/m3) in healthy or asthmatic adults, which is consistent with
findings of the majority of studies of controlled exposures to acid aerosols presented in the last two
PM AQCDs (U.S. EPA, 1996, 079380; 2004, 056905).


      Summary of Controlled Human Exposure Study Findings for Pulmonary Function

      Taken together, the majority of controlled human exposure studies do not provide evidence of
PM-induced changes in pulmonary function; however, some investigators have observed  slight
decreases in DLCO, MMEF, FEVi, oxygen saturation, or increases in airways resistance following
exposure to CAPs, DE, or UF  EC.


6.3.2.3.   lexicological Studies

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) included three animal  toxicological studies
which measured  pulmonary  function following multiday short-term inhalation exposure to CAPs. A
decreased respiratory rate was noted in the one study involving dogs. Increased tidal volume was
observed in one study involving rats while no changes were observed in the other rat study. AHR
was found in four studies of mice, healthy rats or SH rats exposed to ROFA by IT instillation or
inhalation. Studies conducted since the last review are discussed below.


      CAPs

      SH rats exposed to Tuxedo, NY CAPs via nose-only inhalation for 4 h  (mean concentration
73 ug/m3; single-day concentrations 80 and 66 ug/m3; 2/2001 and 5/2001, respectively) had a
statistically significant decreased respiratory rate  compared with air-exposed  controls (Nadziejko  et
al., 2002, 087460). This measure was obtained from BP fluctuations using radiotelemetry. The
decrease in respiratory rate of 25-30 breaths/min was an immediate response  to CAPs, beginning
shortly after the exposure began and ceasing with the end of exposure. It was accompanied by a
decrease in HR (Section 6.2.1.3). Rats were also exposed to fine (MMAD 160 nm; 49-299 ug/m3)
and UF H2SO4(MMAD 50-75 nm; 140-750 ug/m3) (Nadziejko et al., 2002, 087460) because H2SO4
aerosols have the potential to activate irritant receptors. Irritant receptors, found at all levels of the
respiratory tract, include rapidly-adapting receptors and sensory C-fiber receptors (Alarie, 1973,
070967; Bernardi et al., 2001, 019040; Coleridge and Coleridge, 1994, 156362; Widdicombe, 2003,
157145; Widdicombe, 2006, 155519). Activation of trigeminal afferents in the nose causes CNS
reflexes resulting in decreases in respiratory rate through a lengthened expiratory  phase, closure of
the glottis, closure of the nares with increased nasal airflow resistance and effects on the
cardiovascular system such as bradycardia, peripheral vasoconstriction and a rise  in systolic arterial
blood pressure. Sneezing, rhinorrhea and vasodilation with subsequent nasal vascular congestion are
also nasal reflex  responses involving the trigeminal nerve (Sarin et al., 2006,  191166). Activation of
vagal afferents in the tracheobronchial and alveolar regions of the respiratory tract causes CNS
reflexes resulting in bronchoconstriction, mucus secretion, mucosal vasodilation,  cough, and apnea
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followed by rapid shallow breathing. Besides effects on the respiratory system, effects on the
cardiovascular system can also occur including bradycardia and hypotension or hypertension. Fine
H2SO4 induced an overall decrease in respiratory rate, with UF H2SO4 resulting in elevated
respiratory rate compared to control (Nadziejko et al., 2002,  087460). The authors suggested that
both CAPs and fine H2SO4 aerosols activated sensory irritant receptors in the upper airways,
resulting in a decreased respiratory rate. The response to UF H2SO4 aerosols differed from the other
responses and was thought to be due to deposition of UFPs deeper into the lung with the subsequent
activation of pulmonary irritant receptors which trigger an increase in respiratory rate. Since irritant
receptors in nasal, tracheobronchial and alveolar regions act via trigeminal- and vagal-mediated
pathways, this study indicates a role for neural reflexes in respiratory responses to CAPs.
      Kodavanti et al. (2005, 087946) measured respiratory frequency  1 day after a 2-day exposure
of SH and WKY rats to CAPs from RTP, NC (mean mass concentration range 144-2,758 (ig/m3;
<2.5 (im in size;  8/27-10/24/2001) for 4 h/day. Increases in inspiratory  and expiratory times were
seen in SH, but not WKY rats, exposed to CAPs compared with filtered air controls.
      Effects of CAPs on pulmonary function were also investigated in a rat model of pulmonary
hypertension using SD rats pre-treated with monocrotaline (Lei et al., 2004, 087999). In this study,
rats were exposed to CAPs from an urban high traffic area in Taiwan (mean mass concentration
371 (ig/m3) for 6 h/day on three consecutive days and pulmonary function was evaluated 5 h
post-exposure using whole-body plethysmography. A statistically significant decrease in respiratory
frequency and an increase in tidal volume were observed following CAPs  exposure, along with an
increase in airway responsiveness (measured as Penh) following Mch challenge.
      In many animal studies changes in ventilatory patterns  are assessed using whole body
plethysmography, for which measurements are reported as enhanced pause (Penh). Some
investigators report increased Penh as an indicator of AHR, but these are inconsistently correlated
and many investigators consider Penh solely an indicator of altered ventilatory timing in the absence
of other measurements to confirm AHR. Therefore use of the terms AHR or airway responsiveness
has been limited  to instances in which the terminology has been similarly applied by the study
investigators.


      Diesel Exhaust

      Li et al. (2007, 155929) exposed BALB/c and C57BL/6 mice to clean air or to low dose DE
(containing 100 (ig/m3 particles) for 7 h/day and 5 days/wk for 1, 4 and 8 wk. Average gas
concentrations were reported to be 3.5 ppm CO, 2.2 ppm NO2, and <0.01 ppm SO2. AHR was
evaluated by whole-body plethysmography at day 0 and after 1, 4 and 8 wk of exposure. Exposure to
DE for 1  wk resulted in an increased sensitivity of airways to Mch, measured as Penh, in C57BL/6
but not BALB/c, mice. Other short-term responses  of this study are discussed in Sections 6.3.3.3 and
6.3.4.2.
      McQueen et al. (2007, 096266) investigated the role of vagally-mediated pathways in
respiratory responses to PM. Respiratory minute volume (RMV) was increased in anesthetized
Wistar rats 6 h after treatment with 500 (ig DE particles (SRM2975) by IT instillation. This response
was blocked by severing the vagus nerve or pretreatment with atropine. The absence of a respiratory
response with vagotomy or atropine indicated that the increase in RMV following DE particle
exposure involved a neural reflex acting via vagal afferents. No statistically significant changes in
mean BP, HR or HRV were observed in response to DE particles in this study. Vagally-mediated
inflammatory responses to DEP were also observed in this study and are discussed in
Section 6.3.3.3.


      Model Particles

      In a study by Last et al. (2004, 097334). BALB/c mice were exposed to 250 (ig/m3
laboratory-generated iron-soot (size range 80-110 nm; about 200 (ig/m3 as soot) for 4 h/day and
3 days/wk for 2 wk. Pulmonary function was measured by whole-body plethysmography after
challenge with Mch. No AHR, as measured by Penh, was observed following 2-wk exposure to
iron-soot. Other findings of this study are reported in Sections 6.3.3.3 and 6.3.5.3.
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      Summary of Toxicological Study Findings for Pulmonary Function

      Several recent studies demonstrated alterations in respiratory frequency and in airway
responsiveness following short-term exposure to CAPs and DE. Two studies provide evidence for
the involvement of irritant receptors and vagally-mediated neural reflexes in mediating changes in
respiratory functions.


6.3.3.  Pulmonary Inflammation

      The discussion of the effects of PM on pulmonary inflammation in the 2004 PM AQCD
(U.S. EPA, 2004, 056905) was limited by a relative lack of information from controlled human
exposure and toxicological studies. Although no epidemiologic studies of pulmonary inflammation
were described in the 2004 PM AQCD (U.S.  EPA, 2004, 056905). several recent studies have
observed a positive association between PM concentration and exhaled NO (eNO). New controlled
human exposure and toxicological studies have also generally observed an increase in markers of
inflammation in the pulmonary compartment following exposure to PM.


6.3.3.1.  Epidemiologic Studies

      No epidemiologic studies of pulmonary inflammation were described in the 2004 PM AQCD
(U.S. EPA, 2004, 056905).


      Exhaled Nitric Oxide -Asthmatic Children

      Exhaled NO, a biomarker for airway inflammation, was the outcome studied in panels of
asthmatic children in southern California (Wu et al, 2006, 157156) and Seattle (Allen et al., 2008,
156208: Koenig  et al., 2003, 156653: 2005, 087384: Mar  et al., 2005, 088759). Mean concentration
data from these studies are summarized in Table 6-10. Delfino et al. (2006, 157156) followed 45
asthmatic children for ten days with offline fractional eNO and examined the associations with
exposures to personal PM2.5 and 24-h PM2.5, EC and OC as well as ambient PM2.5, EC and OC. The
strongest associations were between eNO and 2-day avg pollutant concentrations: for a 10 (ig/m3
increase in personal PM2.5, eNO increased by 0.46 ppb (95% CI: 0.04-0.79); for 0.6 (ig/m3 personal
EC, eNO increased by 0.7 ppb (95% CI: 0.3-1.1). An association with exposure to ambient PM25
was only statistically significant in 19 subjects taking inhaled corticosteroids: for each 10 (ig/m
increase in PM2.5, eNO increased by 0.77 ppb (95% CI: 0.07-1.47).
      In a panel of 19 asthmatic children in Seattle, effects were observed only among the ten
non-users of inhaled corticosteroids. For each 10 (ig/m3 increase in personal, outdoor, indoor, or
central site PM25, eNO increased from 3.82 ppb (associated with central site, 95% CI: 1.22-6.43) to
4.48 ppb (with personal PM2.5, 95% CI: 1.02-7.93) (Koenig et al., 2003, 156653).  Further analysis
examining the association between eNO and  outdoor and indoor-generated particles suggested that
eNO was associated more strongly with ambient particles,  but only for non-users of medication: each
10 (ig/m3 increase in estimated ambient PM25 results in an increase in eNO of 4.98 ppb (95% CI:
0.28-9.69) (Koenig et al., 2005, 087384).
      Also in Seattle, WA, Mar et al. (2005, 088759) examined the association between eNO and
ambient PM25 concentration among children (aged 6-13 yr) recruited from an asthma/allergy clinic.
Fractional exhaled nitric oxide (FeNO)  was associated with hourly averages of PM25 up to 10-12 h
after exposure. Each 10 (ig/m3 increase in 1-h mean PM25  concentration was associated with a 6.99
ppb increase in eNO (95% CI: 3.43-10.55) among children not taking inhaled corticosteroids, but
associated with only a 0.77 ppb decrease in eNO (95% CI: -4.58 to 3.04) among those taking inhaled
corticosteroids.
      Allen et al. (2008, 156208). in a reanalysis of data from Koenig et al. (2005, 087384).
evaluated the effect of different PM2 5 exposure metrics in relation to airway inflammation among
children in wood smoke-impacted areas of Seattle. The authors found that for the nine non-users of
inhaled corticosteroids,  the ambient-generated component  of PM2 5 exposure was associated with
respiratory responses, both airway inflammation and decrements in lung function, whereas the non-
ambient PM2 5 exposure component was not.  They did note, however, different relationships for
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airway inflammation and decrements in lung function, with the former significantly associated with
total personal PM2 5, personal light-absorbing carbon (LAC), and ambient generated personal PM2.5
and the latter related to ambient PM2 5 and its combustion markers. The different results between
FeNO and lung function were not unexpected; epidemiologic data show that airway inflammation
indicated by FeNO does  not correlate strongly with either respiratory symptoms or lung function
(Smith and Taylor, 2005, 192176). The authors conclude that lung function decrements may be
associated with the combustion-generated component of ambient PM2.5, whereas airway
inflammation may be related to some other component of the ambient PM25 mixture.
     In a longitudinal study, Liu et al. (2009, 192003) examined the association between acute
increases in ambient air pollutants and FeNO among children (ages 9-14 yr) with asthma. FeNO had
a trend of positive associations with PM25, with the strongest association on lag day 0 (3.12% [95%
CI: -2.12 to 8.82]). Copollutant models including O3, SO2 or NO2 did not result in marked changes in
the PM2 5 risk estimates for FeNO.
     A few studies outside of the U.S. examined eNO in relation to PM exposure among children.
Fischer et al. (2002, 025731) and Murata et al. (2007, 189159) found a statistical association
between increases in PM and increases in the percent of eNO. Holguin et al. (2007, 099000) found
no association between exposure to PM and eNO. However, they did see statistical associations
between increases in eNO for the 95 asthmatic subjects and measures of road density of roads 50-
and 75-m from the home.


     Exhaled Nitric Oxide -Adults

     Three recent panel studies examined the effects of particle exposure on eNO measured in older
adults (Adamkiewicz et al., 2004, 087925 in Steubenville, OH; Adar et al.. 2007. 001458; Jansen et
al., 2005, 082236 in Seattle). Mean concentration data from these studies are characterized in Table
6-10. Breath samples were collected weekly for 12 weeks from a group of 29 elderly adults in
Steubenville, OH (Adamkiewicz  et al., 2004, 087925). In single-pollutant models, each 10 (ig/m3
increase in 24-h ambient PM2.5 increased eNO by 0.82 ppb (95% CI: 0.19-1.45), a change of 15%
compared to mean eNO (9.9 ppb). Effects were essentially unchanged in copollutant models that
included ambient and/or indoor NO. The effect estimates for the seven COPD subjects were higher
than for normal subjects  (2.20 vs. 0.45 ppb, p = 0.03) (Adamkiewicz  et al., 2004, 087925).
     In the Seattle panel of older adults (aged 60-86 yr), seven subjects were asthmatic and nine
had a diagnosis of COPD (five with asthma and four without) (Jansen et al., 2005, 082236). Exhaled
NO was measured daily for 12 days, along with personal, indoor, outdoor and central site PMi0,
PM2 5 and BC. The strongest associations between 24-h avg PM and eNO were found for the
asthmatic subjects: 10 (ig/m3 increases in outdoor levels (measured outside the subjects' homes) of
PM25 or PMio were associated with increases in eNO of 4.23 ppb (95% CI: 1.33-7.13), an increase
of 22% above the group  mean of 19.2 ppb, and 5.87 ppb (95% CI: 2.87-8.88), an increase of 31%,
respectively. BC  measured indoors, outdoors or personally was also associated with increases in
eNO (of 3.97, 2.32, and  1.20 ppb, respectively) (Jansen et al., 2005, 082236).
     Adar et al.  (2007, 001458) conducted a panel study of 44 non-smoking senior citizens residing
in St. Louis, MO. As part of the study, subjects were taken on group trips to a theater performance,
Omni movie, outdoor band concert, and a Mississippi River boat cruise. Subjects were driven to and
from each event aboard a diesel bus. Before and after each bus trip, eNO was measured on each
subject. Two carts containing continuous air pollution monitors were used to measure group-level
micro-environmental exposures to PM25, BC, and size-specific particle counts (0.3-2.5 (im and
2.5-10  (im) on the day of each trip. Each 10 ug/m3 increase in 24-h mean PM2 * concentration was
associated with a 36% increase in eNO pre-trip (95% CI: 5-71). Each 10 (ig/m  increase in
micro-environmental PM25 concentration (i.e., during the bus ride) was associated with a 27%
increase in eNO post-trip (95% CI: 17-38).
     These studies all demonstrated an association between increased levels of eNO and increases
in PM in the previous 4-24 h. Further, three studies  demonstrated effects in elderly populations
(Adamkiewicz et al.. 2004. 087925: Adar et al.. 2007. 001458: Jansen et al., 2005, 082236) while
four others reported a similar acute increase in eNO among children (Delfino et al., 2006, 090745;
Koenig et al.,  2003, 156653; 2005, 087384; 2005, 088999).
     Outside of the U.S., one study examined eNO in a panel of 60 adult asthmatic subjects in
London. McCreanor et al. (2007, 092841) reported that 1 (ig/m3 increase in personal exposure to EC
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was associated with increases of approximately 1.75-2.25% in eNO (results were presented
graphically only) for up to 22 h post-exposure.


      Other Biomarkers of Pulmonary Inflammation and Oxidative Stress

      Other biomarkers of respiratory distress that have been examined in recent panel studies
include urinary leukotriene E4 (LTE4) in asthmatic children (Rabinovitch  et al., 2006, 088031); two
oxidative stress markers: TEARS and 8-isoprostane in asthmatic children (Liu et al., 2009, 192003)
and breath acidification in adolescent athletes (Ferdinands et al., 2008, 156433). Mean concentration
data from these studies are characterized in Table 6-10.
      In Rabinovitch et al. (2006, 088031). LTE4, an asthma-related biological mediator, was used to
study the response to short-term particle exposure. In the second winter of their 2-yr study of
asthmatic children (described above in Section 6.3.1.1), urine samples were collected at
approximately the same time of day from 57  subjects for eight consecutive days. Controlling for
days with URI symptoms, each 10 (ig/m3 increase in morning maximum PM25 (measured by
TEOM), was associated with an increase in LTE4 levels by 5.1% (95% CI:  1.6-8.7). No statistically
significant effects were observed on the same day or up to 3 days later based on 24-h averaged
concentrations from the TEOM monitor or from the FRM central site monitor.
      In a longitudinal study conducted in Windsor, Ontario, Liu et al. (2009, 192003) examined the
association between acute increases in ambient air pollutants and TEARS and 8-isoprostane among
children (ages 9-14 yr) with asthma. TEARS, but not 8-isoprostane, was positively associated with
PM2.5 (percent change in TEARS 40.6% [95% CI: 11.8-81.3], lag 0-2 days). The association with
TEARS persisted for at least three days.  Adverse changes in pulmonary function (Section 6.3.2.1)
were consistent with those of TEARS in response to PM2.5 with  a similar lag structure, suggesting a
coherent outcome for small airway function and oxidative stress.
      The effects of vigorous outdoor exercise during peak smog season in Atlanta, GA on breath
pH, a biomarker of airway inflammation, in adolescent athletes (n = 16, mean age = 14.9 yr) were
examined by Ferdinands et al.  (2008, 156433). Median pre-exercise breath pH was 7.58 (range
4.39-8.09) and median post-exercise breath pH was 7.68 (range  3.78-8.17). The authors observed no
significant association between ambient PM and post-exercise breath pH. However both pre- and
post-exercise breath pH were strikingly low in these athletes when compared to 14 relatively
sedentary healthy adults  and to published values of breath pH in healthy subjects. The authors
speculate that repetitive vigorous exercise may induce airway acidification.


      Effect of Measurement Location on Studies  of Pulmonary Function and
      Inflammation

      A number of studies examining exposure to PM2.5 and pulmonary function and inflammation
have compared the results of exposure assessment based on concentrations recorded from personal,
indoor, outdoor, and/or ambient monitors (Allen et al., 2008,  156208; Delfmo et al., 2004, 056897;
Delfmo et al., 2006, 090745; Koenig  et al., 2005, 087384; Trenga et al., 2006, 155209).  Two
investigations evaluated  PM2 5 concentrations from indoor, outdoor, personal and central site
monitors and the relationship with FEVi. Delfmo et al. (2004, 056897) reported that personal
exposure estimates showed a stronger association with FEVi than  any of the stationary exposures,
and that indoor exposure estimates were associated with a stronger effect than either outdoor or
central site  exposure estimates. However, Trenga et al. (2006, 155209) reported the largest declines
in FEVi associated with central site exposure estimates, though the most consistent association with
declines in FEVi came from the exposure estimates measured by indoor monitors. Delfmo et al.
(2006, 090745) used personal and ambient exposure estimates in a study of FeNO among asthmatic
children and found that the personal exposure estimates were more robust than the  ambient exposure
estimates. Two studies conducted in Seattle, WA partitioned personal  exposure to PM2 5 into its
ambient-generated and indoor-generated components. Koenig et al. (2005, 087384) reported that
ambient-generated PM2 5 was consistently associated with an increase in FeNO, while the  indoor-
generated component of PM25 was less strongly  associated with FeNO. This could  reflect the
difference in composition of indoor-generated PM25 as compared to ambient-generated PM25
Similarly, Allen et al. (2008, 156208) found that FeNO was associated with the ambient-generated
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component of personal PM2.5 exposure, but not with ambient PM2.5 concentrations measured by
central site monitors. Overall, these studies provide a unique perspective on how measurement
location influences the findings of epidemiologic studies. This small group of studies indicates that
effects are associated with all types of PM measurement, suggesting health effects of both ambient-
generated and indoor-generated particles. It is likely that variability in season, meteorology,
topography, geography, behavior and exposure patterns contribute to the observed differences.


6.3.3.2.   Controlled Human  Exposure Studies

      Studies of controlled human exposures presented in the 2004 PM AQCD (U.S. EPA, 2004,
056905) provided evidence of pulmonary inflammation induced by exposure to PM. Lay et al.
(1998, 007683) found that instillation of iron oxide particles (2.6 urn) produced an increase in
alveolar macrophages and neutrophils in bronchoalveolar lavage fluid (BALF) collected 24 h
post-instillation. Ohio and Devlin (2001, 017122) evaluated the inflammatory response following
bronchial instillation of particles extracted from filters collected in the Utah Valley both prior to and
after the closure of an area steel mill. Subjects who underwent pulmonary instillation of particles
(500 ug) collected while the steel mill was operating (n = 16) had significantly higher levels of
neutrophils 24 h post-instillation compared with either saline instillation or with subjects (n = 8) who
were instilled with the same mass of PM collected during the mill's closure. This finding indicates
that metals may be an important PM component for this health outcome. In an inhalation study of
exposure to PM2.5 CAPs (23-311 ug/m3) from Chapel Hill, NC, Ohio et al. (2000, 012140) observed
an increase in airway and alveolar neutrophils 18 h after the 2-h exposure. A similar finding was
reported by Rudell et al. (1999, 001964) following exposure to DE among healthy adults. In this
study, reducing the particle number from 2.6x106particles/cm3 to 1.3x10 particles/cm3 while
maintaining the concentration of gaseous diesel emissions was not observed to attenuate the
response. One study of controlled exposures to UF EC among healthy adults did not report particle-
related effects on eNO (Frampton, 2001, 019051). As summarized below, several recent studies of
controlled exposures have provided some additional evidence of pulmonary inflammation associated
with PM.


      CAPS

      A series of exposures to UF, PM2.5, and PMi0_2.5 CAPs from Los Angeles with average particle
concentrations between 100 and 200 ug/m3 have not been shown to have a significant effect on
markers of airway inflammation in healthy or health-compromised adults (Gong et al., 2004,
087964; 2004, 055628; 2005, 087921; 2008, 156483). However, two recent studies conducted in
Chapel Hill, NC reported significant increases in percent PMNs and concentration of IL-8 in BALF
among healthy adults 18-20 h following controlled  exposures to PMi0_25 (89 ug/m3) and UF (49.8
ug/m3) CAPs, respectively (Graff et al., 2009,  191981; Samet et al., 2009, 191913). As discussed
above, the same laboratory previously reported a mild inflammatory response in the lower
respiratory tract following exposure to PM25 CAPs (Ghio et al., 2000, 012140). In a follow-up
analysis, Huang et al. (2003, 087377) found the increase in BALF neutrophils demonstrated by Ghio
et al. (2000, 012140) to be positively associated with the Fe, Se, and SO4 ~ content of the particles.
      Alexis et al. (2006, 154323) recently evaluated the effect of PMi0_2.5 on markers  of airway
inflammation, specifically focusing on the impact of biological components of PMi0_2.s. Healthy men
and women (n = 9) between the ages of 18 and 35 inhaled nebulized saline (0.9%) as well as
aerosolized PMi0_2.5 collected from ambient air. Subjects were exposed to PM10_2.s on two separate
occasions, once using PMi0_2.5 that had been heated to inactivate biological material and once using
non-heated PMi0_2.5. Approximately 0.65 mg PMi0_2.5 was deposited in the respiratory tract of
subjects during the exposures. Markers of inflammation and immune function were analyzed in
induced sputum collected 2-3 h after inhalation of saline or PMi0_2.5. Both heated and non-heated
PMio_2.5 were observed to increase the neutrophil response compared with saline. Exposure to
non-heated PM10_2.5 was found to increase levels of monocytes, eotaxin, macrophage TNF-a mRNA,
and was also associated with an upregulation of macrophage cell surface markers. No such effects
were observed following exposure to biologically inactive PMi0_2.s. These results suggest that while
PMio_2.5-induction of neutrophil response is not dependent on biological components, heat sensitive
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components of PM10_2.5 (e.g., endotoxin) may be responsible for PM-induced alveolar macrophage
activation.


      Traffic Particles

      Larsson et al. (2007, 091375) exposed 16 healthy adults to air pollution in a road tunnel for 2 h
during the afternoon rush hour in Stockholm, Sweden. The median PM2.5 and PMi0 concentrations
during the road tunnel exposures were 64 ug/m3 and 176 ug/m3, respectively. Bronchial biopsies
were obtained and bronchoscopy and BAL were performed 14 h after the exposure. The results were
compared with a control exposure which consisted of exposure to urban air during normal activity.
The authors reported significant BALF increases in percentage of lymphocytes, total cell  number,
and alveolar macrophages following exposure to road tunnel exposure versus control. These results
provide evidence of a significant association between exposure to road tunnel air pollution and
airway inflammation. However, unlike other controlled exposure studies, the control exposure was
not a true clean air control, but  only a lower exposure group with no characterization of personal
exposure. In addition, it is not possible to separate out the contributions of each air pollutant,
including PM, on the observed  inflammatory response.


      Diesel Exhaust

      In a recent study evaluating the effect of DE exposure on markers of airway inflammation,
Behndig et al.  (2006, 088286) exposed healthy adults (n = 15) for 2 h with intermittent exercise to
filtered air or DE with a reported PM10 concentration of 100 ug/m3. Eighteen hours after exposure to
DE, the authors found significant increases in neutrophil and mast cell numbers in bronchial tissue,
as well as significant increases in neutrophil numbers and IL-8 in BALF compared with filtered air
control. Similarly, Stenfors et al. (2004, 157009) observed an increase in pulmonary inflammation
(e.g., airways neutrophilia and an increase in IL-8 in BALF) among healthy  adults 6 h following
exposure to DE (PMi0 average concentration 108 ug/m3). It is interesting to note, however, that no
such inflammatory effects were observed in a group of mild asthmatic subjects in the same study.
The DE-induced neutrophil response in the airways of healthy subjects observed in these  two studies
(Behndig  et al., 2006, 088286;  Stenfors et al., 2004, 157009) is qualitatively consistent with the
findings of Ohio et al. (2000, 012140) who exposed healthy subjects to Chapel Hill PM2.5 CAPs. In a
group of healthy volunteers, Bosson et al. (2007, 156286) demonstrated that exposure to O3 (2 h at
0.2 ppm) may  enhance the  airway inflammatory response of DE relative to clean air (1-h  exposure to
300 ug/m3). Exposure to O3 was conducted 5 h after exposure to DE, and resulted in an increase in
the percentage of neutrophils in induced sputum collected 18 h after exposure to O3. In a  subsequent
study using a similar protocol at the same concentrations, prior exposure to DE was  shown to
increase the inflammatory effects of O3 exposure, demonstrated as an increase in neutrophil and
macrophage numbers in bronchial wash (Bosson et al., 2008, 196659).


      Wood Smoke

      Barregard  et al. (2008, 155675) examined the effect of a short-term exposure (4 h)  to wood
smoke (240-280  ug/m3) on markers of pulmonary inflammation in a group of healthy adults.
Exposure to wood smoke increased alveolar NO compared to filtered air (2.0 ppb versus  1.3 ppb) 3 h
after exposure. Although these results provide some evidence of a PM-induced increase in
pulmonary inflammation, the physiological significance of the relatively small increase in alveolar
NO is unclear.


      Model Particles

      Pietropaoli et al. (2004, 156025) observed a lack of airway inflammatory response  21 h after
exposure to UF EC particles (10-50 ug/m3) among healthy and asthmatic adults. The same laboratory
reported no effect of exposure to UF or fine ZnO (500 ug/m3) on total  or differential sputum cell
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counts 24 h after exposure in a group of healthy adults (Beckett  et al., 2005, 156261). Tunnicliffe
et al. (2003, 088744) measured levels of eNO as a marker of airway inflammation following 1-h
controlled exposures to ammonium bisulfate or aerosolized H2SO4 (200 and 2,000 ug/m3) in a group
of healthy and asthmatic adults. While exposure to ammonium bisulfate increased the concentration
of eNO immediately following exposure in asthmatics, no such effect was observed in healthy
adults, or in either healthy or asthmatic adults following exposure to aerosolized H2SO4.


      Instillation

      Schaumann et al. (2004, 087966) investigated the inflammatory response of human subjects
instilled with PM2.5 (100 ug) collected from two different cities in Germany, Hettstedt and Zerbst.
Although endobronchial instillation of PM from both cities were shown to induce airway
inflammation, instillation of PM from the  more industrial area (Hettstedt) resulted in greater influxes
of BALF monocytes compared to PM collected from Zerbst. The authors postulated that the
difference in response between PM from the two cities may be due to the higher concentration of
transition metals observed in the samples collected from Hettstedt. Another study reported no change
in inflammatory markers in nasal lavage fluid 4 and 96 h following intranasal instillation of DEP
(300 ug/nostril) in asthmatics and healthy  adults (Kongerud et al., 2006,  156656). Pre-exposure of
DEP to O3 was not shown to have any effect on the response. Although not a cross-over design, these
findings suggest that exposure to DEP without the gaseous component of DE may have little effect
on inflammatory responses in human subjects.


      Summary of Controlled Human  Exposure Study Findings for Pulmonary
      Inflammation

      These new studies strengthen the evidence of PM-induced pulmonary inflammation; however,
the response appears to vary significantly  depending on the source and composition of the particles.


6.3.3.3.   lexicological Studies

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) discussed numerous studies investigating
pulmonary inflammation in response to CAPs, ROFA, DEPs, metals and acid aerosols. A wide
variety of responses was reported depending on the type of PM and route of administration. In
general, IT instillation  exposure to fly ash and metal PM resulted in notable pulmonary
inflammation. In contrast, inhalation of sulfates and acid aerosols had minimal, if any, effect on
pulmonary inflammation. More recent animal toxicological studies using CAPs, DE and other
relevant PM types are summarized below.


      CAPs

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) found that exposure to PM2.5 CAPs at
concentrations of 100-1,000 ug/m3 for 1-6 h/day and 1-3 days generally resulted in minimal to mild
inflammation in rats and dogs. Somewhat enhanced inflammation was observed in a model  of
chronic bronchitis. Since the last review, numerous studies have investigated inflammatory  responses
to PM2 5 and UF CAPs in both healthy and compromised animal models.
      In one study of healthy animals, SD rats were exposed to CAPs for 4 h/day on 3 consecutive
days in Fresno, CA, in fall 2000 and winter 2001 (PM25 mean mass concentration 190-847  ug/m3)
(Smith et al., 2003, 042107). The particle concentrator used in these studies was capable of
enhancing the concentration of UF as well as fine particles. Immediately after exposure on the third
day, BALF was collected and analyzed for total cells and neutrophils. Statistically significant
increases were observed in numbers of neutrophils during the first week of the fall exposure period
and in numbers  of total cells, neutrophils and macrophages during the first week of the winter
exposure period. CAPs concentrations were >800 ug/m during both of those weeks.
      Two studies were conducted using CAPs in Boston. In a study by Godleski et al. (2002,
156478), healthy SD rats were exposed for 5 h/day for 3 consecutive days to CAPs ranging  in
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concentration from 73.5-733.0 (ig/m3. BALF and lung tissue were collected for analysis 1 day later.
Neutrophilic inflammation was indicated by a statistically significant increase in percent neutrophils
in BALF. Microarray analysis of RNA from lung tissue and BALF cells demonstrated increased gene
expression of pro-inflammatory mediators, markers of vascular activation and enzymes involved in
organic chemical detoxification. This study overlapped in part with previously described studies by
Saldiva et al. (2002, 025988) and Batalha et al. (2002, 088109) (Section 6.2.4.3). In another study
(Rhoden  et al., 2004, 087969). healthy SD rats were exposed for 5 h to CAPs (mean  mass
concentration 1228 fig/m3; June 20-August 16, 2002). A statistically significant increase in BALF
neutrophils was observed 24 h following CAPs exposure. Histological analysis confirmed the influx
of inflammatory cells (Section 6.3.5.3). Inflammation was accompanied by injury which is discussed
in Section 6.3.5.3.
      Kodavanti et al. (2005, 087946) reported two sets of studies involving PM2.5 CAPs  exposure
during fall months in RTP, NC. In the first study, SH rats were exposed to filtered air  or CAPs (mean
mass concentration range 1,138-1,765 (ig/m3; <2.5 (im) for 4 h and analyzed  1-3 h later. No increase
in BALF inflammatory cells or other measured parameter was observed. In the second study, SH and
WKY rats were exposed to filtered air or CAPs (mean mass concentration range  144-2,758 (ig/m3;
<2.5 (im) for 4 h/day on 2 consecutive days and analyzed 1 day afterward. Differences in  baseline
parameters were noted for the two rat strains since SH rats had greater numbers of BALF  neutrophils
than WKY rats. Following the 2-day CAPs exposure, increased BALF neutrophils were observed in
the WKY rats but not in the SH rats compared with filtered air controls. Inflammation was not
accompanied by increases in BALF markers of injury (Section 6.3.5.3).
      Two CAPs studies involving SH rats were conducted in the Netherlands. In the first, SH rats
were exposed by nose-only inhalation to CAPs (ranging in concentration from 270-3,660  (ig/m3 and
in size from 0.15-2.5 (im) from three different sites in the Netherlands  (suburban, industrial and
near-freeway) for 6 h (Cassee et al., 2005, 087962). Increased numbers of neutrophils were
observed in BALF 2 days post-exposure compared to air controls. When CAPs exposure was used as
a binary term, the relationship between CAPs concentration and number of PMN in BALF was
statistically significant. In contrast, Kooter et al. (2006, 097547) reported no changes  in markers of
pulmonary inflammation measured 18 h after a 2-day exposure (6 h/day) of SH rats to PM2.5 or
PM2.5+UFP CAPs from sites in the Netherlands (mean mass concentration range 399-3613 and
269-556 ug/m3, respectively; PM2.5 CAPs site in Bilthoven and PM2 5+UF CAPs  site in freeway
tunnel in Hendrik-Ido-Ambacht).
      Pulmonary inflammation was investigated in two studies using a rat model of pulmonary
hypertension (i.e., SD rats pre-treated with monocrotaline). In the first study,  rats were exposed to
PM25 CAPs from an urban high traffic area in Taiwan (mean mass concentration of 371 (ig/m3) (Lei
et al., 2004, 087999) for  6 h/day on 3 consecutive days and BALF was collected 2 days later. A
statistically significant increase in total cells and neutrophils was observed in BALF. Levels of TNF-
a and IL-6 in the BALF were not altered by CAPs exposure. In the second study, rats were exposed
to PM25 CAPs (mean mass concentration 315.6 and 684.5 ug/m3 for 6 and 4.5 h, respectively;
Chung-Li area, Taiwan) during a dust storm event occurring March 18-19, 2002 (Lei  et al., 2004,
087884). Only one animal served as control during the 6-h exposure (from 2100-300  on the first
exposure day) so results from that one animal were combined with that of three control animals from
the 4.5-h exposure (from 300-730) on the second exposure day. A statistically significant increase in
total cells and neutrophils in BALF occurred in both CAPs-exposed groups. In addition, increases in
BALF IL-6 and markers  of injury (Section 6.3.5.3) were observed as a function of CAPs exposure.
      In summary, pulmonary inflammation was noted in all three studies involving multiday
exposure of healthy rats to CAPs from different locations. No pulmonary inflammation was seen in
one study of SH rats exposed to CAPs for 4 h and analyzed 1-3 h later. In studies involving multiday
exposure of SH rats, one demonstrated pulmonary inflammation while two did not. In the rat
monocrotaline model of pulmonary hypertension, both single-day and multiday exposures to CAPs
resulted in mild pulmonary inflammation.


      On-Road Exposures

      In a study by Elder et al. (2004, 087354) old rats  (21 mo) were exposed to  on-road highway
aerosols (particle concentration range 0.95-3.13xl05 particles/cm3; mass concentration estimated to
be 37-106 (ig/m3; Interstate 90 between Rochester and Buffalo, NY) for 6 h on one or three
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consecutive days. No increase in BALF inflammatory cells was observed 18 h post-exposure in any
of the treatment groups.


      Urban Air

      To evaluate inflammatory responses to ambient particles from vehicles, Wistar rats were
exposed to ambient urban air from a high traffic site (concentration range 22-225 (ig/m3 PMi0; Porto
Alegre, Brazil) or to the same air which was filtered to remove the PM (Pereira et al, 2007,
156019). Concentrations of gases were not reported. Compared with controls exposed to filtered
urban air, a significant increase in total number of BALF cells was observed 24 h following the 20 h
continuous exposure, but not following the 6 h of exposure to unfiltered urban air.


      Diesel Exhaust

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) summarized findings of the 2002  EPA Diesel
Document regarding the health effects of DE. Short-term inhalation exposure to low levels of DE
results in the accumulation of diesel PM in lung tissue, pulmonary inflammation and alveolar
macrophage aggregation and accumulation near the terminal bronchioles. More recent studies are
summarized below.
      Pulmonary inflammatory responses were investigated in C57BL/6 mice exposed to DE
7 h/day for 6 consecutive days (Harrod et al., 2003, 097046). Compared with controls, inflammatory
cell counts in BALF were increased in mice exposed to the higher concentration of DE (1,000 (ig/m
PM) but not in mice exposed to the lower concentration  of DE (30 (ig/m3 PM). Concentrations of
gases present in the higher dose DE were reported to be  43 ppm NOX, 20 ppm CO and 364 ppb SO2.
      In a second study evaluating DE effects on BALF inflammatory cells, no increases in numbers
of neutrophils, lymphocytes or eosinophils were observed in BALB/c mice exposed by inhalation to
500 or 2,000 (ig/iri  DE particles for 4 h/day on 5 consecutive days (Stevens et al., 2008, 1570101
Concentrations of gases reported in this study were  4.2 ppm CO, 9.2 ppm NO, 1.1 ppm NO2, and
0.2 ppm SO2 for the higher concentration of DE. Transcriptional microarray analysis demonstrated
upregulation of chemokine and inflammatory cytokine genes, as well as genes involved in growth
and differentiation pathways, in response to the higher concentration of DE. No gene expression
results were reported for the lower concentration of DE.  Sensitization and challenge with ovalbumin
(OVA) significantly altered these findings (Section 6.3.6.2). These results demonstrate that changes
in gene expression can occur in the absence of measurable pulmonary inflammation or injury
markers (Section 6.3.5.3).
      Li  et al. (2007, 155929) exposed mice to clean air or to low dose DE (100 (ig/m3 PM) for
7 h/day and 5 days/wk for 1, 4 and 8 wk as described in  Section 6.3.2.3. Analysis of BALF and
histology of lung tissues was carried out at day 0 and after 1, 4 and 8 wk of exposure. Total numbers
of cells and macrophages in BALF were significantly increased in C57BL/6 mice, but not in
BALB/c  mice, after 1-wk exposure to DE compared with 0 day controls. Neutrophils and
lymphocytes were increased after 1-wk exposure to DE in both strains compared with 0 day controls.
Differences in BALF cytokines were also noted between the two strains after 1-wk exposure to DE.
No changes were observed by histological analysis. Pulmonary function  and oxidative responses
were also evaluated (Sections 6.3.2.3 and 6.3.4.2). Long-term exposure responses are discussed in
Sections  7.3.2.2, 7.3.3.2 and 7.3.4.1.
      Healthy F344 rats and A/J mice were exposed to DE containing 30, 100, 300 and 1,000 (ig/m3
PM by whole body inhalation for 6 h/day, 7 days/wk for either 1 wk or 6 months in a study by Reed
et al. (2004, 055625). Concentrations of gases were reported to be from 2.0-45.3 ppm NO,
0.2-4.0 ppmNO2, 1.5-29.8 ppm CO and 8-365 ppb for SO2 in these exposures. One week of
exposure resulted in no measurable effects on pulmonary inflammation. Long-term exposure
responses are discussed in Section 7.3.3.2.
      In a study by Wong et al. (2003, 097707).  also reported by Witten et al. (2005, 087485).
F344/NH rats were exposed nose-only to filtered room air or to DE at concentrations of 35.3 (ig/m3
and 669.3 (ig/m3 PM  (particle size range 7.2-294.3 nm) for 4 h/day and 5 days/wk for 3 wk. Gases
associated with the high dose exposure were  reported to be 3.59 ppm NO, 3.69 ppm NOX, 0.1 ppm
NO2, 2.95 ppm CO, 518.96 ppm CO2 and 0.031 ppm total hydrocarbon. The focus of this study was
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on the possible role of neurogenic inflammation in mediating responses to DE. Neurogenic
inflammation is characterized by both the influx of inflammatory cells and plasma extravasation into
the lungs following the release of neuropeptides from bronchopulmonary C-fibers. Pulmonary
inflammation was evaluated by histological analysis of lung tissue at the end of the 3-wk exposure
period. Following high, but not low, concentration exposure to DE, a large number of alveolar
macrophages was found in the lungs. Small black particles, presumably DE particles, were found in
the cytoplasm of these alveolar macrophages. Perivascular cuffing consisting of mononuclear cells
was also observed in high dose-exposed animals. Influx of neutrophils or eosinophils was not seen,
although mast cell number was increased in high-dose exposed animals. Pulmonary plasma
extravasation was measured by the 99mTechnecium-albumin technique and found to be
dose-dependently increased in the bronchi and lung parenchyma. Alveolar edema was also observed
by histology in high concentration-exposed animals. A significant decrease in substance P content in
lung tissue was reported in DE-exposed rats. These responses initially suggested that DE resulted in
stimulation of C-fibers and activation of a local axon reflex resulting in the repeated release of the
stored neuropeptide substance P. Subsequent experiments were conducted using capsaicin
pretreatment, which inhibits neurogenic inflammation by activating C-fibers and causing the
depletion of neuropeptide stores. Pretreatment with capsaicin was found to reduce the influx of
inflammatory cells, but not plasma extravasation, in response to DE. Hence, DE is unlikely to act
through bronchopulmonary C-fibers to  cause neurogenic edema in this model, although there may be
a different role for bronchopulmonary C-fibers in mediating the inflammatory cell influx.
     Stimulation of bronchopulmonary C-fibers can result in activation of both local and CNS
reflexes through vagal parasympathetic pathways. McQueen et al. (2007, 096266) investigated the
role of vagally-mediated pathways in acute inflammatory responses to DE particles. A statistically
significant increase in BALF neutrophils was observed 6 h after IT instillation treatment of
anesthetized Wistar rats with 500 ug DE particles (SRM2975). This response was blocked by
severing the vagus nerve or pretreatment with atropine (McQueen et al., 2007, 096266). Similarly,
atropine treatment blocked the increase in BALF neutrophils seen 6 h after DE particle  exposure in
conscious Wistar rats. These results provide evidence for the involvement of a pulmonary vagal
reflex in the inflammatory response to DE particles.
     In summary, several studies demonstrate that short-term inhalation exposure to DE
(100-1,000 ug/m  PM) causes pulmonary inflammation in rodents. No attempt was made in these
studies to determine whether the responses were due to PM components or to gaseous components.
However, PM from DE  was found to be capable of inducing an inflammatory response, as
demonstrated by the one IT instillation  study described above.  Evidence was presented  suggesting
that DEP may act through bronchopulmonary C-fibers to stimulate pulmonary inflammation.


     Gasoline Emissions and Road Dust

     Healthy male Swiss mice were exposed to gasoline exhaust (635 ug/m3 PM and associated
gases) or filtered air for 15 min/day for 7, 14, and 21 days (Sureshkumar et al., 2005, 088306).
BALF was collected for analysis 1  h after the last exposure. Histological analysis was also carried
out at 7, 14, and 21 days. The number of leukocytes in BALF was increased after exposure to
gasoline exhaust, but this increase did not achieve statistical significance. However, levels of the
pro-inflammatory cytokines TNF-a and IL-6 were significantly increased in BALF following 14 and
21 days of exposure. Furthermore, inflammatory cell infiltrate  in the peribronchiolar and alveolar
regions were observed by histology. Evidence of lung injury was also found (Section 6.3.5.3). In this
study, BALF analysis of inflammatory cells was a less sensitive indicator of pulmonary
inflammation than BALF  analysis of cytokines and histological analysis of lung tissue.  Results of
this study cannot entirely be attributed to the presence of PM in the gasoline exhaust since
0.11 mg/m3 SOX, 0.49 mg/m3 of NOX and 18.7 ppm of CO were also present during exposure.
     Using ApoE"7" mice on  a high-fat  diet, Campen et al. (2006, 096879) studied the impact of
inhaled gasoline emissions and road dust (6 h/day><3 day) on pulmonary inflammation.  For gasoline
emissions, the PM-containing atmosphere (PM mean concentration 61 ug/m3; NOX mean
concentration 18.8 ppm; CO mean concentration 80 ppm) failed to increase numbers  of
inflammatory cells in BALF collected 18 h after the last exposure. However, a statistically
significant increase in total cells  and macrophages was observed in response to resuspended road
dust (PM25) at 3,500 ug/m3, but not at 500 ug/m3.
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      Model Particles

      In a study by Elder et al. (2004, 055642). pulmonary inflammation was investigated in two
compromised, aged animal models (11-14 mo old SH and 23 mo old F344) exposed by inhalation to
UF CB (count median diameter = 36 nm) at a relevant concentration (150 ug/m3). No changes in
BALF cells were seen 24 h post-exposure in either model.
      An increase in BALF neutrophils was observed at 24 h, but not at 4 h, in WKY rats exposed to
UF carbon particles (median particle size 38 nm; mass concentration 180 ug/m3; mean number
concentration 1.6xl07 particles/cm3) for up to 24 h (Harder et al., 2005, 087371). Changes in HR
and HRV demonstrated in this study (Section 6.2.1.3) occurred much more rapidly than the
inflammatory response.
      No evidence of pulmonary inflammation was found by analysis of BALF or histology one or
three days following 24-h exposure of SH rats to UF carbon particles under similar conditions
(median particle size 31 nm; mass concentration  172 ug/m3; mean number concentration 9.0xl06
particles/cm3) (Upadhyay  et al., 2008, 159345). However increased expression of HO-1, ET-1, ETA
and ETB, tPA and, plasminogen activator-1 was found in lung tissue three days following exposure.
      In a study by Gilmour et al.  (2004, 054175), adult Wistar rats were exposed for 7 h to fine  and
UF CB particles (mean mass concentration 1,400 and 1,660 ug/m3 for fine and UF CB, respectively;
mean number concentration 3.8><103 and 5.2><104 particles/cm , respectively; count median
aerodynamic diameter 114 nm and 268 nm, respectively). Both treatments resulted in increased
BALF neutrophils 16 h post-exposure, with the UFPs having the greater response. UFPs also
increased total BALF leukocytes and macrophage inflammatory protein-2 (MIP-2) mRNA in BALF
cells. Although these exposures may not be relevant to ambient exposures, this study demonstrated
the greater propensity of UF CB particles to cause a pro-inflammatory response compared with fine
CB particles.
      In a study by Last et al. (2004, 097334).  mice were exposed to 250 ug/m3 laboratory-generated
iron-soot over a 2-wk period as described in Section 6.3.2.3. BALF was collected 1-h after the last
exposure and analyzed for total cells. No increase in total cell number was observed following
iron-soot exposure. Other findings of this study are described in Sections 6.3.2.3 and 6.3.5.3.
      Pinkerton et al. (2008, 190471) exposed young adult male  SD rats to filtered air, iron, soot or
iron-soot for 6 h/day for 3 days. The iron particles were mainly less than 100 nm aerodynamic
diameter, while the soot particles were initially 20-40 nm in diameter but formed clusters of 100-
200 nm in diameter. The size-distribution of iron-soot particles was bimodal over 10-250 nm and
averaged 70-80 nm in diameter. Rats were exposed to 45, 57 and 90 ug/m3 iron or to 250 ug/m3 soot
alone or in combination with 45 ug/m3 iron. Increased levels of the pro-inflammatory cytokine IL-1J3
were observed in lung tissue of rats exposed for 6 h/day for 3 days to 90 ug/m3, but not 57 ug/m3,
iron. No change in BALF  inflammatory cells was observed after exposure to 57 ug/m3 or 90 ug/m3
iron. Exposures to 250 ug/m3 soot in combination with 45 ug/m3 iron also resulted in increased
levels of lung IL-1(3 and activation of the transcription factor NF-KB. Levels of lung IL-1(3 were
increased in neonatal rats exposed to 250 ug/m3 soot in combination with  100, but not 30, ug/m3
iron. Other endpoints of this study are described in Section 6.3.4.2.


      Summary of lexicological Study Findings for Pulmonary Inflammation

      New studies involving short-term exposures to CAPs and urban air strengthen the evidence of
PM-induced pulmonary inflammation. In addition, several studies  demonstrated pulmonary
inflammation in response to diesel and gasoline exhaust;  however it is not known whether PM or
gaseous components of the exhaust were responsible for these effects. Mixed results were obtained
in studies using model particles such as CB and iron-soot.
6.3.4.  Pulmonary Oxidative Responses
      The results of a small number of controlled human exposure and toxicological studies
presented in the 2004 PM AQCD (U.S. EPA, 2004, 056905) provided some initial evidence of an
association between exposure to PM and pulmonary oxidative stress. Recent controlled human
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exposure studies have provided support for previous findings of an increase in markers of pulmonary
oxidative stress following exposure to DE, and one new study has observed a similar effect
following controlled exposure to wood smoke. New findings from toxicological studies provide
further evidence that oxidative species are involved in PM-mediated effects. No epidemiologic
studies have evaluated the association between PM concentration and pulmonary oxidative response.


6.3.4.1.  Controlled Human Exposure Studies

      Two studies cited in the 2004 PM AQCD (U.S. EPA, 2004, 056905) observed effects on
markers of airway oxidative response in healthy adults following controlled exposures to fresh DE or
resuspended DE particles (Blomberg et al., 1998, 051246: Nightingale  et al, 2000, 011659).
Several recent studies are described below which have further evaluated the oxidative response
following exposure to particles in human  volunteers.


      Diesel Exhaust

      Pourazar et al. (2005, 088305)  exposed 15 adults (11 males  and four females) for 1 h to air or
DE (PMio concentration 300 ug/m ) in a controlled cross-over study. Bronchoscopy with airway
biopsy was performed 6 h after exposure.  The expression of NF-KB, AP-1 (c-jun and c-fos), p38, and
JNK in bronchial epithelium was quantified using immunohistochemical staining. DE was observed
to significantly increase nuclear translocation of NF-KB, AP-1, phosphorylated p38, and
phosphorylated JNK; however, the findings of this study require confirmation with more quantitative
methods such as Western blot analysis. The observed activation of redox-sensitive transcription
factors by DE may result in the induction  of pro-inflammatory cytokines. There is some evidence to
suggest that this bronchial response to DE is mediated through the epidermal  growth factor receptor
signaling pathway (Pourazar et al., 2008, 156884). Behndig et al.  (2006, 088286) evaluated the
upregulation of endogenous antioxidant defenses following exposure to DE (100 ug/m3 PMi0) in a
group of 15 healthy adults. Increases  in urate and reduced GSH were observed in alveolar lavage,
but not bronchial wash, 18 h after exposure. In a study utilizing the same exposure protocol,
Mudway et al. (2004, 180208) observed an increase in GSH and ascorbate in  nasal lavage fluid 6 h
following exposure to DE in a group  of 25 healthy adults.


      Wood Smoke

      Barregard et al. (2008, 155675) observed a significant increase in malondialdehyde levels in
breath condensate of healthy volunteers (n =  13) immediately following and 20 h after a 4-h
exposure to wood smoke (240-280 ug/m  PM).


      Endobronchial Instillation

      Schaumann et al. (2004, 087966) demonstrated an increased oxidant radical generation of
BALF cells following endobronchial instillation of urban particles compared  with instillation of
particles collected in a rural area. The authors suggested that this difference was likely due to the
greater concentration of transition metals  found in the urban particles.


      Summary of Controlled Human  Exposure Study Findings for Pulmonary Oxidative
      Responses

      Taken together, these studies suggest that short-term exposure to PM at near ambient levels
may produce mild oxidative stress in the lung. Limited data suggest that proximal and  distal lung
regions may be subject to different degrees of oxidative  stress during exposures to different pollutant
particles.
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6.3.4.2.   Toxicological Studies
      The 2004 PM AQCD (U.S. EPA, 2004, 056905) reported one study which provided evidence
that ROS were involved in PM-mediated responses. This particular study used pre-treatment with the
antioxidant DMTU to block the neutrophilic response to ROFA. More recently, several studies
evaluated the effects of PM exposure on pulmonary oxidative stress. Oxidative stress can be directly
determined by measuring ROS or oxidation products of lipids and proteins. An indirect assay
involves measurement of the  enzyme HO-1 or of the antioxidant enzymes SOD or catalase, all of
which can be induced by oxidative stress. Antioxidant interventions which inhibit or prevent
responses are a further indirect measure of oxidative stress playing a role in the pathway of interest.


      CAPS
      Gurgueira et al. (2002, 036535) measured oxidative stress as in situ CL. Immediately
following a 5-h PM2.5 CAPs exposure (mean mass concentration range 99.6-957.5 ug/m3; Boston,
MA) increased CL was observed in lungs of CAPs-exposed SD rats. CL evaluated after CAPs
exposure durations of 3 h was also increased but did not achieve statistical significance compared to
the filtered air group. When animals were allowed to recover for 24 h following the 5-h CAPs
exposure, CL levels returned to control values. Interestingly, a decrease in lung CL was observed in
rats breathing filtered air for three days compared with rats breathing room air for the same duration.
To compare potential particle-induced differences in in situ CL, rats were exposed to ROFA (1.7
mg/m3 for 30 min) or CB (170 ug/m3 for 5 h). Only the ROFA-treated animals exhibited increased
CL in lung tissue.  Additionally, levels of antioxidant enzymes in the lung (MnSOD and catalase)
were increased in  CAPs-exposed rats. A CAPs-associated increase in CL was also seen in the heart
(Section 6.2.9.3), but not the liver.
      In a similar  study, Rhoden et al. (2004, 087969) exposed SD rats for 5 h to  PM2.5 CAPs from
Boston (mean mass concentration 1,228 ug/m3) or to filtered air. Significant increases in TEARS
and protein carbonyl content (a measure of protein oxidation) were observed 24 h post-exposure to
CAPs. Pretreatment with the thiol antioxidant NAC (50 mg/kg i.p.) 1-h prior to exposure prevented
not only the lipid and protein oxidation observed in response to CAPs, but also the increase in BALF
neutrophils and pulmonary edema in this model (Sections 6.3.3.3 and 6.3.5.3). Results of this study
demonstrate the key role played by oxidative stress in these CAPs-mediated effects.
      A later study by  Rhoden et al. (2008, 190475) investigated the role of superoxide in mediating
pulmonary inflammation following exposure to ambient air particles. In this study, adult SD rats
were exposed by IT instillation to 1 mg of SRM1649. Two hours prior to exposure, half of the rats
were pretreated with the membrane-permeable SOD mimetic MnTBAP (10 mg/kg, i.p.). MnTBAP
abrogated the inflammatory response, measured by increased BALF inflammatory cells, and the
increase in lung superoxide, measured by CL, observed 4 h following exposure to urban air particles.
      Kooter et al. (2006, 097547) reported an increase in HO-1 in BALF and lung tissue measured
18 h after a 2-day  exposure (6 h/day) of SH rats to PM2.5 or PM2.5+UF CAPs (mean mass
concentration range 399-3613 and 269-556 ug/m3, respectively; PM25 CAPs site in Bilthoven and
PM2 5+UF site in freeway tunnel in Hendrik-Ido-Ambacht, the Netherlands). This occurred in the
absence of any measurable pulmonary inflammation (Section 6.3.3.3).


      Urban Air

      To  evaluate oxidative stress responses to ambient particles from vehicles, Wistar rats were
exposed to ambient urban air from a high traffic site (concentration range 22-225  ug/m3 PMi0; Porto
Alegre, Brazil) or to the same air which was filtered to remove the PM (Pereira et al., 2007,
156019).  Several exposure regimens were carried out: 6- and 20-h continuous exposures or to
intermittent exposures of 5 h/day for four consecutive days. A significant increase in lipid
peroxidation (measured as malondialdehyde) was seen in lung tissue immediately following the 20-h
continuous exposure, but not following the 6-h exposure or the intermittent exposures.
Inflammation-related endpoints are described in Section 6.3.3.3.
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      Diesel Exhaust

      Li et al. (2007, 155929) exposed mice to clean air or to low dose DE (100 (ig/m3 PM) for
7 h/day and 5 days/wk for 1, 4 and 8 wk as described in Section 6.3.2.3. HO-1 mRNA and protein
were increased in lung tissues of both mouse strains after 1 wk of DE exposure. In addition, AHR
and changes in BALF cells and cytokines were observed (Sections 6.3.2.3 and 6.3.3.3). Pretreatment
with the thiol antioxidant NAC (320 mg/kg, i.p.) on days 1-5 of DE exposure greatly attenuated the
AHR  and inflammatory response seen after 1 wk of DE exposure. Long-term responses are
discussed in Sections 7.3.2.2, 7.3.3.2 and 7.3.4.1.
      A study by Whitekus et al. (2002, 157142) investigated the adjuvant effects of DE particles in
an allergic animal model and is discussed in detail below (Section 6.3.6.3). Intervention with the
thiol antioxidants bucillamine and NAC inhibited the increases in allergen-specific IgE and IgGi as
well as the increases in protein carbonyl and lipid hydroperoxides in the lung following DE particle
exposure.


      Gasoline Exhaust

      Pulmonary oxidative stress was evaluated by measurement of CL and TEARS following
exposure of SD rats to gasoline engine exhaust (Seagrave et al., 2008, 191990). Animals were
exposed for 6 h in a nose-only inhalation exposure system. PM mass concentration was reported to
be 60  ug/m3;  count median diameter 20 nm; mass median diameter 150 nm; while the concentrations
of gaseous copollutants were 104 ppm CO, 16.7 ppmNO, 1.1 ppmNO2 and 1.0 ppm SO2. A
statistically significant increase in lung CL was observed without a concomitant increase in lung
TEARS. Discordant results were also observed for road dust exposures in the heart (Section 6.2.9.3).
The discrepancy between oxidative stress indicators suggests that the responses may follow different
time courses. Furthermore, no CL was seen when the gasoline exhaust was filtered to remove the
particulate fraction.


      Model Particles

      Increased expression of HO-1 was observed in lung tissue three days following 24-h exposure
of SH rats to UF carbon particles (median particle size  31 nm; mass concentration 172 ug/m3; mean
number concentration 9.0x106 particles/cm3) despite no evidence of pulmonary inflammation
(Section 6.3.3.3) (Upadhyay  et al., 2008, 159345)
      In a study conducted by Pinkerton et al.  (2008, 190471). young adult male SD rats  were
exposed to filtered air, soot, iron or iron-soot for 6 h/day for three days as described in Section
6.3.3.3. A statistically significant decrease in total antioxidant power and a statistically significant
increase in glutathione-S-transferase activity were observed in lung tissue from rats exposed to 90
(ig/m3 iron. This high concentration iron exposure also  resulted in increased levels of ferritin protein
in lung tissue, indicating the  presence of free iron which has the potential to redox cycle and cause
oxidative stress. Lung tissue  total antioxidant power was decreased and glutathione redox ratio was
increased by the combined exposure to 250 (ig/m3 soot and 45 (ig/m3 iron. The iron-soot exposure
also increased oxidized glutathione in BALF and lung tissue. These results demonstrate that co-
exposure to soot enhanced iron-mediated oxidative stress. Furthermore, co-exposure to soot and iron
resulted in increased expression of cytochrome P450 isozymes CYP1A1  and CYP2E1 in lung tissue,
an effect not observed in response to either agent alone. Inflammation-related endpoints observed in
this study are described in Section 6.3.3.3.
      In a parallel study, Pinkerton et al. (2008, 190471) exposed neonatal male SD rats to iron-soot
or filtered air 6 h/day for three days during the second and fourth week of life. Both 30 (ig/m3 and
100 (ig/m3 iron in combination with 250 (ig/m3 soot resulted in increased BALF oxidized
glutathione, glutathione redox ratio and glutathione-S-transferase activity and decreased total
antioxidant power. The higher concentration exposure resulted in increased ferritin expression in
lung tissue. Effects on cellular proliferation in specific regions of the lung were also noted as
described in Section 6.3.5.3.
      Nurkiewicz et al. (2009, 191961) exposed SD rats to fine (count median diameter 710 nm) and
UF (count median diameter 100 nm) TiO2 particles via aerosol inhalation at concentrations of 1.5-16
December 2009                                 6-113

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mg/m3 for 240-720 min. These exposures were chosen in order to produce deposition of 4-90 ug/rat,
which was demonstrated in a previous study to result in different degrees of impaired microvascular
function (Nurkiewicz et al., 2008, 156816). Histological analysis of lung tissue did not find any
significant inflammation, although particle accumulation in alveolar macrophages and a frequent
association of alveolar macrophage with the alveolar wall was observed 24 h following exposure
(Nurkiewicz  et al., 2008, 156816). Although the main focus of the more recent study was on effects
of TiO2 on NO production and microvascular reactivity in the spinotrapezius muscle
(Section 6.2.4.3), the presence of nitrotyrosine was determined in both lung tissue and spinotrapezius
muscle as a measure of peroxynitrite formation. Peroxynitrite formation occurs mainly as a result of
the rapid reaction of NO with superoxide and suggests an increase in local superoxide production.
The area of lung tissue containing nitrotyrosine immunoreactivity increased three-fold 24 h
following exposure to 10 ug UF TiO2. Nitrotyrosine immunoreactivity was localized in
inflammatory cells found in the alveolar region of the lung.


      Summary of lexicological Study  Findings for Pulmonary Oxidative Responses

     New studies involving short-term exposure to CAPs, urban air, diesel and gasoline exhaust,
and model particles such as CB, iron-soot and TIO2 consistently demonstrate pulmonary oxidative
responses. Furthermore, antioxidant treatment ameliorated effects observed in response to CAPs,
DE and DE particles.
6.3.5.   Pulmonary Injury

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) presented evidence from several toxicological
studies of small PM-induced increases in markers of pulmonary injury including thickening of
alveolar walls and increases in BALF protein. These findings are consistent with the results of recent
toxicological and controlled human exposure studies demonstrating mild pulmonary injury
accompanying inflammatory responses to CAPs and wood smoke. One recent epidemiologic study
has also observed a positive association between PM and urinary concentrations of lung Clara cell
protein.


6.3.5.1.   Epidemiologic Studies

      One epidemiologic study examined biomarkers of pulmonary injury. The mean concentration
data from this study are characterized in Table 6-10. Timonen et al. (2004, 087915) enrolled subjects
with coronary heart disease in Amsterdam (n = 37), Erfurt, Germany (n = 47) and Helsinki (n = 47)
to study daily variation in PM and urinary concentrations of lung Clara cell protein (CC16). No
associations were seen between the PNC of the smallest particles (NC0.oi-o.i) and CC16. Significant
associations with NC0.i-i and PM25 (which were strongly correlated with each other [r = 0.8]) were
seen only for Helsinki subjects: same day, lag 3 and 5-day mean NC0.i-i increases of 1000
particles/cm3 were associated with increases in In (CC16/creatinine) of 15.5% (95% CI: 0.001-30.9),
17.4% (95% CI: 3.4-31.4),  and 43.2% (95% CI: 17.4-69.0), respectively. Similar associations were
seen for 10 (ig/m3 increases in PM25: lag 0 and 5-day mean PM25 were associated with increases in
In (CC16/creatinine) of 23.3% (95% CI: 6.3-40.3) and 38.8% (95% CI: 15.8-61.8), respectively.


6.3.5.2.   Controlled Human Exposure Studies

      No studies of controlled human exposures presented in the 2004 PM AQCD (U.S. EPA, 2004,
056905) specifically examined the effect of PM on pulmonary injury. However, several recent
studies have evaluated changes in markers of injury and increased alveolar permeability following
exposures to various types  of particles.
December 2009                                 6-114

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      Urban Traffic Particles

      Brauner et al.(2009 190244) evaluated the effect of exposure to urban traffic particles (24-h
exposure, PM2.5 9.7 ug/m ) on the integrity of the alveolar epithelial membrane in a group of 29
healthy adults, with and without exercise. Following 2.5 h of exposure, alveolar epithelial
permeability was assessed by measuring the pulmonary clearance of 99mTc-DTPA, which was
administered as  an aerosol during 3 min of tidal breathing. While pulmonary clearance of
99mTc-DTPA was observed to increase following exercise, there was no significant difference in
clearance between exposure to urban traffic particles and filtered air. In addition, PM exposure was
not observed to  affect the level of CC16 in plasma or urine at 6 or 24 h after the start of exposure.


      Diesel Exhaust

      Relative to filtered air, exposure for 1 h to DE (300 ug/m3 PM) was not observed to affect the
plasma CC16 concentration at 6 or 24 h post exposure in a group of 15 former smokers with COPD
(Blomberg  et al., 2005, 191991).


      Wood Smoke

      In a study examining the respiratory effects of wood smoke, Barregard et al. (2008, 155675)
exposed two groups  of healthy adults in separate 4-h sessions to wood smoke with median particle
concentrations of 243 and 279 ug/m3. At 20 h post-exposure, the mean serum CC16 concentration
was significantly higher after exposure to wood smoke when compared with filtered air. However,
when the analysis was stratified by exposure session, a statistically significant effect of wood smoke
on serum CC16  was observed in the subjects in session 1 but not those in session 2. It is interesting
to note that while the mean particle concentration was  only slightly higher in session 1, the mean
particle number in session 1 was almost 90% higher than the particle number in session 2, with
geometric mean particle diameters of 42 and 112 nm, respectively.


      Summary of Controlled Human Exposure Study Findings for Pulmonary Injury

      The findings from these studies provide limited  evidence to suggest that exposures to particles
may increase markers of pulmonary injury in healthy adults.


6.3.5.3.  lexicological Studies

      The 2004  PM AQCD (U.S.  EPA, 2004, 056905) reported mild increases in BALF protein, a
marker of pulmonary injury, in several studies involving inhalation exposure to CAPs. In addition,
histological analysis demonstrated that the bronchoalveolar junction was the site of the greatest
inflammation following CAPs exposure. Low level  exposure to DE was associated with Type 2 cell
proliferation and thickening of alveolar walls near alveolar macrophages according to the 2002 EPA
Diesel Document (U.S. EPA, 2002, 042866). In addition, IT instillation of fly ash and
metal-containing PM generally caused pulmonary injury as measured by increases in BALF  protein,
LDH  and albumin. Proliferation of bronchiolar epithelium was also noted. More recent studies of
BALF markers of pulmonary injury  and histological analysis of lung tissue are summarized below.


      BALF Markers of Pulmonary Injury and Increased Permeability


      CAPs

      Kodavanti et al.  (2005, 087946) exposed SH and WKY rats to filtered air or PM2.5  CAPs from
RTP, NC as described in Section 6.3.3.3. Differences in baseline parameters were noted for the two
rat strains since  SH rats had greater levels of protein and lower levels of LDH, NAG, ascorbate and
December 2009                                 6-115

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uric acid in the BALF compared with WKY rats. One day after the 2-day CAPs exposure, increased
levels of GGT were observed in BALF (a marker of epithelial injury) of SH rats, but not WKY rats,
compared with filtered air controls. Injury was not accompanied by inflammation (Section 6.3.3.3).
      In a study by Cassee et al. (2005, 087962). SH rats were exposed for 6 h by nose-only
inhalation to CAPs from three different sites in the Netherlands as described in Section 6.3.3.3. The
pulmonary injury marker CC16 was increased in BALF two days following CAPs exposure.
Inflammation was also observed (Section 6.3.3.3).
      Gurgueira et al. (2002, 036535) exposed SD rats to Boston, MA CAPs as described in
Section 6.3.4.2 and reported a small but statistically significant increase in lung wet/dry ratios after 3
and 5 h of exposure, indicating the presence of mild edema. This response was accompanied by
increased oxidative stress as measured by in situ CL (Section 6.3.4.2). In a similar study, Rhoden
et al. (2004, 087969) reported an increase in lung wet/dry ratio in rats 24 h following a 5-h exposure
to Boston CAPs which was diminished by pre-treatment of the antioxidant NAC (Section 6.3.4.2).
      Pulmonary injury was investigated in two studies using a rat model of pulmonary hypertension
(SD rats pre-treated with monocrotaline) which is described in greater detail in Section 6.3.3.3 (Lei
et al., 2004, 087999). Significant increases in BALF LDH and protein were observed in response to
CAPs. Pulmonary inflammation was observed in both of these studies (Section 6.3.3.3).

      Diesel Exhaust

      In a study evaluating the effects of DE, no changes were observed in BALF  protein and LDH
in mice exposed by inhalation to concentrations of 50 and 2000 (ig/m3 DE particles for 4 h/day on 5
consecutive days as described in Section 6.3.3.3 (Stevens  et al., 2008, 157010). Changes in gene
expression were observed in the higher exposure group. This  study demonstrates that changes in
gene expression can occur in the absence of measurable markers of injury or pulmonary
inflammation.
      In a study by Wong et al. (2003, 097707). also reported by Witten et al. (2005, 087485). rats
were exposed nose-only to filtered room air or to DE over a 3-wk period. This study, focusing on
neurogenic inflammation, is described in greater detail in Section 6.3.3.3. Pulmonary plasma
extravasation was measured by the 99mTechnecium-albumin technique and found to be
dose-dependently increased in the bronchi and lung. Pretreatment with capsaicin, which inhibits
neurogenic inflammation by activating C-fibers and causing the depletion of neuropeptide stores, did
not reduce plasma extravasation following DE exposure. Hence, DE  is unlikely to act through
bronchopulmonary C-fibers to cause neurogenic edema in this model. Inflammatory responses
measured in this study are discussed in Section 6.3.3.3.

      Gasoline Exhaust

      Healthy male Swiss mice were exposed to gasoline exhaust (635 ug/m3 PM and associated
gases) or filtered air for 15 min/day for 7,  14, and 21 days as  described in Section 6.3.3.3
(Sureshkumar et al.,  2005, 088306). BALF was collected for analysis 1-h after the last exposure.
Statistically significant increases in BALF markers of lung injury, alkaline phosphatase,
gamma-glutamyl transferase and LDH, were observed at all time points studied. Alveolar edema was
noted following 14 and 21 days of exposure. Other findings of this study, including inflammation
and histopathological changes, are discussed in Section 6.3.3.3 and below.


      Histopathology


      CAPs

      Histopathological changes were demonstrated in rats exposed for 5 h to Boston CAPs as
described in Section 6.3.3.3 (Rhoden  et al., 2004, 087969). Slight bronchiolar inflammation and
thickened vessels at the bronchiole were observed 24 h post-exposure, consistent with the influx of
polymorphonuclear leukocytes observed in BALF (Section 6.3.3.3).
December 2009                                 6-116

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      Diesel Exhaust

      In a study by Wong et al. (2003, 097707). also reported by Witten et al. (2005, 087485). rats
were exposed nose-only to filtered room air or to DE over a 3-wk period. This study, focusing on
neurogenic inflammation, is described in greater detail in Section 6.3.3.3. Pulmonary inflammation
was evaluated by histological analysis of lung tissue.  Following high, but not low,
concentration-exposure to DE, a large number of alveolar macrophages was found in the lungs.
Small black particles, presumably DE particles, were found in the cytoplasm of these alveolar
macrophages. Perivascular cuffing consisting of mononuclear cells was also observed in the high
exposure animals. Influx of neutrophils or eosinophils was not seen although mast cell number was
increased. Other indices of injury demonstrated in this study are described above.

      Gasoline Exhaust

      Another study, which is described in greater detail in Section 6.3.3.3, demonstrated
histopathological responses to gasoline exhaust in mice exposed to gasoline exhaust or filtered air
for 15 min/day for 7, 14, and 21 days (Sureshkumar et al., 2005, 088306). Histological observations
showed inflammatory cell infiltrate in the peribronchiolar and alveolar region, alveolar edema and
thickened alveolar septa at 14 and 21 days post-exposure. Levels of pro-inflammatory cytokines and
marker enzymes of lung damage were also increased  in BALF. The numbers of inflammatory cells in
BALF was increased but not significantly, demonstrating that BALF analysis of inflammatory cells
was a less sensitive indicator of pulmonary inflammation in this study than histological analysis.
Other indices of injury found in this study are described above.

      Model Particles

      In a study investigating the effects of iron-soot, mice were exposed to 250 (ig/m3
laboratory-generated iron-soot as described in Sections 6.3.2.3 and 6.3.3.3 (Last et al., 2004,
097334). Analysis of airway collagen content was conducted by histology and by biochemical
analysis of microdissected airways. No increases in airway collagen content were found by either
method in mice exposed to iron-soot for two weeks. Furthermore, no goblet cells were observed in
airways of air or iron-soot exposed  animals. Other findings of this study are described in Sections
6.3.2.3 and 6.3.3.3.
      One study demonstrating histopathological responses to PM in neonatal rats was reported by
Pinkerton et al. (2004, 087465). Rat pups (10 days old) were exposed to soot and iron particles
(mean mass concentration of 243 (ig/m ; iron concentration 96 (ig/m3; size range 10-50 nm) for
6 h/day on 3 consecutive days. Cell proliferation in different lung regions was evaluated following
bromodeoxyuridine injection 2 h prior to necropsy. The rate of cell proliferation in the proximal
alveolar region (immediately beyond the terminal bronchioles) was significantly reduced in iron-soot
exposed animals compared to controls. This was a region-specific response since the rate of cell
proliferation was not altered in the terminal bronchioles or the general lung parenchyma. However
alveolar septation, the process by which alveoli are formed during development, and alveolar growth
were not altered by iron-soot exposure. Decreased cell viability and increased LDH was also noted
in BALF of neonatal rats (Pinkerton et al., 2008, 190471). The authors suggest the possibility of
greater susceptibility to air pollution during the critical postnatal lung development period which
occurs in animals and humans and that neonatal exposure to PM may contribute to impaired lung
growth seen in children.


      Summary of lexicological Study Findings for Pulmonary Injury

      New studies involving short-term exposure to CAPs and diesel and gasoline exhaust
demonstrate mild pulmonary injury, including enhanced BALF markers of injury, pulmonary edema
and histopathology.  In general, injury responses were accompanied by inflammatory responses.  In
addition, altered cellular proliferation in the proximal alveolar region was observed in neonatal rats
exposed to iron-soot, suggesting the possibility of greater susceptibility to PM during postnatal lung
development.
December 2009                                 6-117

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      Relative Toxicity of PM Size Fractions


      Ambient PM Studies

      A recently undertaken multinational project entitled "Chemical and biological characterization
of ambient thoracic coarse (PMi0_2.5), fine (PM2.5_o.2), and UFPs (PM0.2) for human health risk
assessment in Europe" (PAMCHAR) takes a systematic approach to expanding the present
knowledge about the physiochemical and toxicological effects of these three PM size fractions. Six
European cities were selected that represented contrasting ambient PM profiles: Helsinki, Duisburg,
Prague, Amsterdam, Barcelona, and Athens. For PM collected at all sites, PMi0_2.5 induced the
greatest pulmonary effects in C57BL/6J mice IT instilled with 1, 3, or 10 mg/kg of particles (Happo
et al., 2007, 096630). Dose-response relationships in BALF parameters measured 24 h post-IT
instillation exposure, including cell number and protein, were observed for all sites following
PMio_2.5, and neutrophils were the predominant cell type present in the BALF (Happo  et al., 2007,
096630). Prague PMi0_2.s exposure resulted in decreased macrophages in BALF at 12 h,  and
Amsterdam, Barcelona, and Athens PMi0_2.5 induced lymphoplasmacytic cells in BALF  (Happo et
al., 2007, 096630). No inflammatory responses were observed for UFPs measured 12-h after
exposure. Protein was elevated for PMi0_2.5 for all locations with the 10 mg/kg dose; Athens UFPs
induced protein release only at the two lowest doses 12 h post-exposure. For TNF-a and IL-6, the
greatest response was observed with PMi0_2.5 4 h following exposure (Happo et al., 2007, 096630).
Exposure to UFPs from Duisburg resulted in elevated TNF-a for the 1 and 3 mg/kg doses. Only the
Helsinki sample appeared to induce the same level of IL-6 release for PMi0_2.5 and PM0.2 at 10
mg/kg, albeit the collection times differed. In vitro TNF-a and IL-6 responses did not always  reflect
in vivo effects (Table 6-11), as the Duisburg PMi0_2.5 sample was the most potent in vivo compared
to the other sites and elicited  much lower cytokine release compared to other cities (except Helsinki)
in vitro (Happo et al., 2007, 096630; Jalava  et al., 2006, 155872; Jalava et al., 2008, 098968).
Helsinki PM was collected in the spring and generally had the lowest in vivo and in vitro activity for
PMio_2.5 compared to the other cities (Happo  et al., 2007, 096630; Jalava et al., 2006, 155872;
Jalava et al., 2008, 098968).  Spring-time samples were collected because episodes of resuspended
road dust occur frequently during this season (Pennanen  et al., 2007, 155357). There was a high
correlation between EC content in PM2 5 and PM10_2.5, indicating that traffic impacted both size
fractions (Sillanpaa  et al., 2005, 156980). Duisburg PM collected in fall had the greatest amounts of
Mn and Zn compared to PM samples from other locations (Pennanen  et al., 2007, 155357). Metals
industries in Duisburg are likely contributors to the observed PM metals concentrations. For the
Prague winter PM samples, the As content was higher than at any other location (Pennanen et al.,
2007, 155357). Prague also had the highest PAH levels in all three size fractions, possibly
attributable to stable atmosphere conditions and incomplete combustion of coal and biomass in
residential heating (Pennanen et al., 2007, 155357). High levels of ammonium and nitrate in  PM
samples from Amsterdam suggest traffic as a large source of air pollution (Pennanen et  al., 2007,
155357). Approximately one-third of PMi0_2.5 mass from Amsterdam was comprised of sea salt
(Sillanpaa et al., 2005, 156980). double that of any other city.  In Barcelona and Athens, high
calcium or Ca2+ contents in spring and summer PM25 and PMi0_2.5 are indicative of resuspended
soil-derived particles (Pennanen et al., 2007,  155357).
December 2009                                 6-118

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Table 6-11.   PAMCHAR PMi0.2.6 inflammation results with ambient PM.
City and Season

Helsinki spring
Duisburg fall
Prague winter
Amsterdam winter
Barcelona spring
Athens summer
BALF protein
+10
+10
+10
+10
+10
+10
BALF TNF-a
+10
+10
[+310]
+10
+10
[+310]
In Vivo3 (mg/kg)
BALF IL-6
+10
+10
+10
+10
[+310]
[+310]
BALF KC
[+310]
+10
[+310]
+10
+10
[+310]
BALF PMN
+10
+10
+10
+10
+10
+10
In
BALF AM TNF-a
+150,300
+150,300
+10 +150,300
+150
+150,300
+150,300
Vitro" (ug/mL)
IL-6
+150,300
+150,300
+150,300
+150,300
+150,300
+150,300
MIP-2
+150,300
+300
+150,300
+150,300
+150,300
+150,300
                                                "Source: Happo et al. (2007, 096630): 2 cell lines used for in vitro study were RAW264.7
                 bSource: Jalava et al. (2006,155872): + indicates increased response and numbers that follow indicate at which dose the response was observed


      Schins et al. (2004, 054173) employed PM from two cities in Germany, Duisburg and Borken,
in another study. In contrast to the PAMCHAR study where animals were administered PM
suspended in pathogen-free water (Happo et al., 2007, 096630). animals received PM via IT
instillation suspended in  saline at a dose of 320 ug (Schins  et al., 2004, 054173). In female Wistar
rats, neutrophils in BALF were significantly elevated for PMi0_2.5 from Duisburg and Borken (Table
6-12), albeit the percent of neutrophils with the PMi0_2.5 from Borken was nearly double that of
Duisburg. The responses with PM2.5 were much smaller. When these PM10_2.5 particles were
introduced into whole blood to determine overall inflammogenic capacity, IL-8 and TNF-a were
released in greater quantities than in response to PM2.5. Furthermore, PMi0_2.5 from Borken induced
higher cytokine responses than Duisburg PMi0_2.5.
      An in vivo study involving SH rats was conducted  using PMio_2.5 and PM2 5 from six different
European locations with  varying traffic densities (3 or 10 mg/kg IT instillation; UFPs were not
collected) (Gerlofs-Nijland  et al., 2007, 097840). It was reported that PM10_2.5  generally induced
greater responses than PM25. IT instillation of PMi0_2.s from a location with high traffic influence in
Munich, Germany, demonstrated the greatest response in terms of LDH activity, protein, total cells,
neutrophils, and lymphocytes in BALF 24 h post-exposure. PMi0_2.5 collected from a low traffic site
in Munich induced the greatest cytokine response for TNF-a and MIP-2. Some correlations were
observed between PMi0_2 5 components (Ba and Cu) and BALF parameters, but were largely driven
by one location (Gerlofs-Nijland  et al., 2007, 097840).


Table 6-12.    Other ambient PM - in vivo PMi0-2.6 studies - BALF results, 18-24 h post-IT exposure.
Location
Germany, Borken; rural Feb-May 2000
Germany, Duisburg; heavy industry
Feb-May 2000
USA, Seattle, WA
Feb-March 2004
USA, Salt Lake City, UT
Apr-May 2004
USA, South Bronx, NY
Dec 2003-Jan 2004
USA, Sterling Forest, NY
Dec 2003-Jan 2004
Endotoxin Dose Cell n/tnUno
(-Values) (mg/kg) Differentials °yiOKme
6.6 EU/mg 0.58-0.91 t*%PMN t TNF-a
5.0 EU/mg 0.58-0.91 t % PMN t MIP-2
6.0 EU/mg 1.25,5.0
6.3 EU/mg 1.25,5.0
2.8 EU/mg 1.25,5.0 fPMN t MIP-2
2.9 EU/mg 1.25,5.0
Injury
s Biomarkers e erence
Schins et al. (2004, 054173)
Schins et al. (2004, 0541731
Gilmour, et al. (2007, 0964331
t protein Gilmour, et al. (2007, 0964331
Gilmour, et al. (2007, 0964331
Gilmour, et al. (2007, 0964331
December 2009
6-119

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        Location
Endotoxin    Dose        Cell
(~ Values)   (mg/kg)    Differentials
<***"»•   Bio'Sers
Reference
USA, RTP, NC

Oct-Nov1996

Germany, Munich Ost Bahnhof; high
traffic A
Aug 2002


Netherlands, Hendrik-ldo-Ambacht;
high traffic
Sept 2002


Italy, Rome; high traffic
Apr 2002


Netherlands, Dordrecht; moderate
traffic
Apr 2002


Germany, Munich Grosshadern
Hospital; low traffic
Jun-Jul 2002


Sweden, Lycksele; low traffic
Feb-March 2002


0.96EU/mg 0.5,2.5,5.0 tt PMN

tf total cells
ttAM
2.9EU/mg 3,10
tt*PMN
tt* Lymph
tt total cells
tt*AM
3,10
6.5 EU/mg tt PMN
tt Lymph
t total cells
ttAM
1.5 EU/mg 3,10
ttPMN
tt Lymph
tt total cells
tAM
0.6 EU/mg 3,10
ttPMN
t Lymph
t total cells
ttAM
2.9 EU/mg 3,10
ttPMN
tt Lymph
tt total cells
tAM
0.9 EU/mg 3,10
ttPMN
t Lymph

tlL-6


tt MIP-2
tt TNF-a


t MIP-2
tt TNF-a


tt MIP-2
tt TNF-a





tt* MIP-2
tt* TNF-a








tt*LDH
t* protein


ttLDH
t protein


ttLDH


ttLDH
t protein


tt*LDH
t protein


ttLDH
t protein


Dick (2003, 088776)


Gerlofs-Nijland, et al.


Gerlofs-Nijland, et al.


Gerlofs-Nijland, et al.


Gerlofs-Nijland, et al.


Gerlofs-Nijland, et al.


Gerlofs-Nijland, et al.





(2007, 0978401


(2007, 0978401


(2007, 0978401


(2007, 0978401


(2007, 0978401


(2007, 0978401

For Gerlofs-Nijland study, composition data were averaged across seasons. | significant only at highest dose.
tt Significant at lowest and highest dose.
* Greatest potency for that endpoint and study. Gilmour et al. (2007, 096433)exposure was via aspiration.


      A more recent study by these investigators (Gerlofs-Nijland et al., 2009, 190353) compared
responses to PM from three different European cities based on size fraction and content of metals
and PAH. SH rats were IT instilled with 7 mg/kg PM, and markers of toxicity and inflammation were
measured in BALF 24 h later. Blood markers of coagulation were also measured and are described in
Section 6.2.8.3. In the first part of the study, both PM2.5 and PMi0_2.5 from Duisburg were found to
have dramatic effects on inflammatory  cell influx and activation as well as  on the injury markers
LDH, protein and albumin in the BALF. The antioxidant species uric acid was increased in BALF
from rats exposed to both size fractions and was interpreted as an adaptive  response to oxidative
stress. Statistical analysis demonstrated that PMi0_2.5 was more potent in eliciting these responses
than PM2.s. In the  second part of the study, responses to metal-rich PM from Duisburg and metal-
poor PM from Prague were determined. A statistically significant greater enhancement of BALF
markers of inflammation and injury was observed for the Duisburg PM compared with the Prague
PM. Furthermore, responses to PAH-rich PMi0_2.5 from Prague and PAH-poor PMi0_2.5 from
Barcelona were determined. PMi0_2.5 from Prague was found to have statistically significant greater
effects compared with PMi0_2.5 from Barcelona. However, organic extracts  of these PMi0_2.5 fractions
had very little capacity  to produce inflammation or toxicity in this  model. These findings suggest an
important role for specific components  associated with PMi0_2.5 in mediating the pro-inflammatory
effects.
December 2009
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      In another study investigating specific components of PM10_2.5, BALB/c mice were IT instilled
with 25 and 50 ug PMio-2.5 from a rural area of the San Joaquin Valley, California (Wegesser and
Last, 2008, 190506). Inflammatory cell influx into BALF began at 6 h and peaked at 24 h following
IT instillation with 50 ug PM, with the increase in neutrophils preceding the increase in
macrophages. Pro-inflammatory effects were found to be mainly due to insoluble components of
PM. Furthermore, heat-treatment, which was capable of inactivating endotoxin, had no effect on
inflammation. Numbers of neutrophils in the BALF were found to correlate with the content of MIP-
2, a known neutrophil chemoattractant released from macrophages and epithelial cells. Taken
together, these results demonstrate that the pro-inflammatory effect of this PMi0_2.5 was associated
with insoluble components and not with endotoxin.
      In an in vivo study that employed ambient PM collected in fall 1996 from RTP, NC,
neutrophilic influx was observed in BALF of female GDI mice 18 h post-IT instillation (10, 50 or
100 ug) of coarse PM (3.5-20 um), although a dose-response relationship was not evident (Dick et
al., 2003, 088776). Mice were also exposed to fine (1.7-3.5 um) and fine/ultrafme (<1.7 um) PM
fractions. Only the two highest doses of PM for the smaller size fractions induced elevated
neutrophils. Significant responses in albumin and TNF-a were only observed for the fine PM
(1.7-3.5 um) exposure group. Total protein, LDH and NAG responses were unchanged from control
levels for all PM size fractions. Levels of IL-6 were elevated in mice exposed to 100 ug for coarse,
fine, and fine/ultrafme (<1.7 um) PM. When dimethylthiourea (DMTU) was administered
intravenously prior to exposure, the neutrophil response was attenuated in all groups to levels below
control.
      Another study compared PMi0_25, PM25, and UFPs collected in Seattle, WA, Salt Lake City,
UT, South Bronx, NY, and Sterling Forest, NY (Gilmour et al., 2007, 096433). In female BALB/c
mice, the 100 ug dose of PMi0_2.5 (approximately 5 mg/kg) from Salt Lake City induced a significant
increase in protein in BALF, and the level released was almost as high as that observed after LPS
exposure. PMi0_2.5 from the South Bronx resulted in dose-related increases in neutrophil number and
MIP-2 levels in BALF. In contrast, no effects were observed with PMi0_2.5 from Sterling Forest. The
greatest amount of LPS was observed in the Salt Lake City and Seattle PMi0_2.s samples. There was a
less discernable pattern of response with fine and UFPs.

      Coal Fly Ash

      Coal fly ash of differing size fractions and composition was administered to female GDI mice
via oropharyngeal aspiration (25 or 100 ug) to assess lung inflammation and injury 18 h following
exposure (Gilmour et al., 2004, 057420). Montana (low-sulfur subbituminous; 0.83% sulfur, 11.72%
ash content) or western Kentucky (high-sulfur bituminous; 3.11% sulfur, 8.07% ash content) coal
was combusted using a laboratory-scale down-fired furnace. Interestingly, no significant effects on
BALF neutrophils, TNF-a, MIP-2, albumin, total protein, LDH activity, or NAG activity were
observed 18 h post-exposure to PMi0_2.5 from either coal fly ash.  However, the UF fraction (PM0.2)
of combusted Montana coal induced greater numbers of neutrophils than PM10_2.5 or PM25 at both
doses. TNF-a was only elevated in animals exposed to 100 ug of the Montana UFPs; MIP-2 was also
increased at both doses. The PM2 5 western Kentucky coal fly ash caused increased BALF
neutrophils, MIP-2, albumin, and protein (Gilmour et al., 2004, 057420).
      In a similar study employing Montana subbituminous coal fly ash particles >2.5 um,
C57BL/6J mice were IT instilled with PM alone or PM+LPS and BALF  was obtained 18 h
post-exposure (Finnerty et al., 2007, 156434). TNF-a and IL-6 in lung homogenates were only
elevated in the animals exposed to PM+100 ug LPS, although it appeared that there was a
greater-than additive effect. Total cells and cell differentials were not measured.


      Summary of lexicological Study Findings for Relative Toxicity of PM Size Fractions

      Biomarkers of injury and inflammation were measured in in vivo and in vitro studies
comparing the toxicity of different size fractions of ambient PM from various locations. Responses
were measured in BALF from rodents following IT instillation or aspiration of PM. In general, the
PMio_2.5 size fraction was more potent than PM2 5 or UFPs and endotoxin levels did not appear
responsible. In one study,  rural PMi0_2.5 from Germany induced a greater inflammatory and cytokine
response than PM10_2.5 from an industrial location. In contrast, PM10_2.5 from Sterling Forest, NY did
not lead to any change in BALF inflammation or injury markers. A study that employed coal fly ash
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indicated that the UF fraction was the most inflammogenic. All of these studies were conducted
using high doses of PM (0.58-10 mg/kg) and it is unclear if similar effects would be observed at
lower doses.


6.3.6.  Allergic Responses

      A large number of toxicological and controlled human exposure studies cited in the 2004 PM
AQCD (U.S. EPA, 2004, 056905) reported an exacerbation of existing allergic airway disease
following exposure to laboratory-generated and ambient particles. In addition, numerous studies
have demonstrated that PM can alter the immune response to challenge with specific antigens and
suggest that PM may act as an adjuvant to promote allergic sensitization. Recent toxicological
studies have provided evidence of enhanced allergic responses and allergic sensitization following
exposure to CAPs and DE that is consistent with the findings presented in the 2004 PM AQCD. PM
can enhance allergic responses by facilitating delivery of allergenic material and promoting
subsequent immune reactivity. The initiation or exacerbation of allergic responses has important
implications for allergic asthma, the most common form of asthma. Additionally, PM has been
shown to alter ventilatory measures in non-allergic animal  models, suggesting a possible role in
other forms of asthma.


6.3.6.1.   Epidemiologic Studies

      Allergy contributes to a number of respiratory morbidity outcomes, including asthma.
However, relatively few epidemiologic studies of PM have specifically examined indicators of
allergy. The 2004 PM AQCD (U.S. EPA, 2004,  056905) presented one study (Hajat  et al., 2001,
016693) showing an association between doctor visits for allergic rhinitis and PM10 among children
in London. This association was strongest at a lag of 3 or 4 days.  Similar results were obtained  in a
new study by  Tecer et al. (2008, 180030), which found significant associations between PM2.5,
PMio_2.5, and PMi0  with hospital admissions for allergic rhinitis in Turkish children, particularly at
lag day 4. While exacerbation of allergic symptoms may occur relatively rapidly, repeated or longer
exposures may be required for allergic sensitization to develop; a number of studies associating long-
term exposure to PM with specific indicators of allergic sensitization are described in Chapter 7.


6.3.6.2.   Controlled Human  Exposure Studies



      Exacerbation of Allergic Responses


      Diesel Exhaust and Diesel Exhaust Particles

      Exposure to DE particles was shown to increase the  allergic response among atopic
individuals in several controlled human exposure studies cited in  the 2004 PM AQCD (U.S. EPA,
2004, 056905).  Nordenhall et al.  (2001, 025185) found that exposure to DE significantly decreased
the concentration of Mch required to induce a 20% decrease in FEVi in a group of atopic asthmatics
24 h post-exposure. In addition,  Diaz-Sanchez et al. (1997, 051247) demonstrated an increase in
allergen-specific IgE following exposure via intranasal spray to ragweed plus DE particles (0.3 mg)
relative to ragweed allergen alone. Decreases in IFN-y and IL-2, as well as increases in IL-4, IL-5,
IL-6, IL-10, and IL-13 were also observed when ragweed allergen was administered with DE
particles. It should be noted that the DE particles used in this study were collected during a cold start
of a light-duty Isuzu diesel engine, and thus contained relatively high levels of incomplete
combustion materials and semi-volatiles organics (e.g., PAHs). One new study using the same source
of DE particles  (Bastain  et al., 2003,  098690) also observed an increase in IL-4 and allergen specific
IgE, as well as a decrease in IFN-y following intranasal administration of ragweed allergen with DE
particles (0.3 mg) in atopic adults. The protocol was repeated in this study for all subjects, and the
enhancement  of allergic response by coexposure to DE particles was observed to be highly
reproducible within individuals. In addition, Gilliland et al. (2004, 156471) demonstrated that GST
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polymorphisms may alter the adjuvant effects of DE particles on allergic response, with individuals
with GSTM1 null or GSTP1 1105 wild type genotypes showing the largest effects.


      Allergic Sensitization


      Diesel Exhaust Particles

      One controlled human exposure study has demonstrated that de novo sensitization to a
neoantigen can be induced by exposure to DE particles. In this  study, Diaz-Sanchez et al. (1999,
011346) dosed 25 atopic adults intranasally with 1 mg keyhole limpet hemocyanin (KLH), followed
by two biweekly challenges with 100 ug KLH. In 15 of the 25 subjects, cold-start DE particles (0.3
mg) were administered intranasally 24 h prior to each KLH exposure, while in the other ten subjects,
no DE particles were administered. No KLH-specific IgE was observed in the nasal lavage fluid of
any of the subjects exposed to KLH without exposure to DE particles. However, KLH-specific IgE
was present in the nasal lavage fluid of 9 out of 15 subjects 28-32 days after the initial KLH
immunization when exposures were preceded by administration of DE particles.

      CAPs

      Increased levels of eotaxin, a marker of allergic activation, were observed in healthy adult
volunteers after inhalation of nebulized ambient Chapel Hill PMi0_2.5 (Alexis  et al., 2006, 154323).
This particular effect was found to be due to endotoxin, based on its elimination by heat-inactivation;
study details are provided in Section 6.3.3.2.


6.3.6.3.   lexicological Studies



      Exacerbation of Allergic Responses

      Increased use of actual ambient air particle mixes in toxicological studies since the 2004 CD
has greatly expanded evidence relevant to assessing these and other immunotoxic effects. A number
of studies have also included ambient-level concentrations, although many still include relatively
high doses of questionable relevance compared to the doses inhaled by humans. Recent dosimetric
models reveal that a small fraction of epithelial cells located at  the carinal ridges of airway
bifurcations can receive massive doses that may be even a few hundred times higher than the
average dose for the whole airway (Chapter 4). These areas, coincidentally, are locations of bronchus
associated lymphoid tissues (BALT) which are sites at which interaction of T and B lymphocytes
with antigen presenting cells (APC) occurs. Hence the deposited particles are in near-ideal proximity
to immunologically active tissues. Doses used for assessing PM immunotoxicity should be viewed
with this perspective. In many animal studies, changes in ventilatory patterns are assessed using
whole body plethysmography, for which measurements are reported as enhanced pause (Penh).
Some investigators report increased Penh  as an indicator of AHR, but these are inconsistently
correlated and many investigators consider Penh solely an indicator of altered ventilatory timing in
the absence of other measurements to confirm AHR. Therefore use of the terms AHR or airway
responsiveness has been limited to instances in which the terminology has been similarly applied by
the study investigators.

      CAPs

      Existing allergic sensitization confers susceptibility to the effects of PM in rodent models. For
example, studies in allergic rats (Harkema et al., 2004, 056842; Morishita et al., 2004, 087979)
suggest that allergic sensitization enhances the retention of PM in the airways. Recovery of
anthropogenic trace elements (La, V, Mn,  S) from lung tissue was greater for Detroit  PM2.5 CAPs
exposed OVA sensitized/challenged BN rats than for air exposed or non-allergic CAPs exposed
controls (24 h post-exposure for 4 or 5 consecutive 10-h days during July or September; time
weighted avg mass concentration of 676 ± 288 or 313 ± 119 (ig/m3, respectively) (Harkema et al.,
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2004, 056842). Interestingly, despite lower avg mass concentration, increases in these elements were
observed in September, when the avg number concentration of UFPs was nearly double that of July
(10,879 ± 5,126 vs. 5,753 ± 2,566 particles/cm3). September CAPs was associated with eosinophil
influx and BALF protein content, as well as significantly increased airway mucosubstances, and the
authors speculated that the high concentration of UFPs facilitated particle penetration into the
alveolar region of the lungs. IT instillation of fractionated insoluble PM2.5 collected from this period
resulted in a mild pulmonary neutrophilic inflammation in healthy BN rats, but no differential effects
were obtained after IT instillation of total, soluble, or insoluble PM2.5 in allergic rats.
      Research has also been conducted to determine the effect of proximity to the roadway on
exacerbation of existing allergic disease.  OVA-allergic BALB/c mice were exposed to PM2.5 or UF
(<0.15 um) CAPs, (avg total concentration 400 ug/m3) for five 4-h days a week over 2 wk at 50 or
150 m downwind of a heavily trafficked road (Kleinman et al., 2005, 087880). Markers of allergy
(serum OVA-specific IgE and IgGl, lung IL-5  and eosinophils) were significantly higher in mice
exposed to CAPs (PM2.5 or UF) than in air-exposed mice after OVA challenge. IL-5, IgGl, and
eosinophils were higher in mice closer to the roadway (50 m) than in mice 150 m downwind. The
authors suggest that the enhanced responses closer to the roadway may reflect a greater proportion of
UFPs in this vicinity, given that the concentrations of sub-25-nm particles decrease rapidly with
distance from the roadway and the PM2 5 CAPs closer to the roadway contained a greater number  of
particles for a similar mass, a portion of which were UF. Animal-to-animal variability among the
biomarkers tested made it necessary to combine values from two exposures spanning two years for
statistical power (determined prior to the start of the experiment). A subsequent publication
(Kleinman  et al., 2007, 097082) included a third exposure regimen as well as compositional
analysis. PM2 5 CAPs mass concentration was intentionally adjusted to an avg concentration of
approximately 400 ug/m3, ranging from 163 to 500 ug/m3, with an estimated particle number of
2.1*105 particles/cm  at 50 m and 1.6xl05 particles/cm3 at 150 m. UFPs ranged from 146 to
430 ug/m3, with particle counts of 4.9 ± 1.4xl05particles/cm3 at 50 m, and 4.4 ± 2.1xl05
particles/cm3 at 150 m. Analysis of results from the three exposures indicated that OVA-sensitized
mice exposed 50 m downwind of the roadway  exhibited increased levels of IL-5 and IgGi compared
to mice exposed 150 m downwind or exposed to air. No markers of allergy-related responses were
observed in the 150 m exposure groups, and very little difference was seen between PM25 and UF
CAPs responses, perhaps because PM2 5 contained 20-32% UF components. The strongest
associations between component concentrations and biological markers of allergy (IL-5 and IgGl)
were with EC and OC. These studies demonstrate that CAPs can enhance allergic responses, and that
proximity to a source may be an important factor.
      In a BN rat model for allergic asthma (Heidenfelder et al., 2009, 190026). thirteen 8-h days of
exposure to Grand Rapids, MI PM2 5 CAPs alone did not result in differential gene expression or
indicators of asthmatic pathology in the lung, but the combination of CAPs and OVA resulted in
differential expression of genes predominantly related to inflammation and airway remodeling, along
with significant increases in IgE, mucin, and total protein in BALF.  Consistent with these changes in
gene expression and BALF markers, OVA with CAPs also induced a more severe allergic
bronchopneumonia (distribution and severity of bronchiolitis and alveolitis) and increased mucus
cell metaplasia/hyperplasia and mucosubstances, indicating exacerbation of allergic or asthmatic
disease. CAPs was collected in July and characterized as having an average mass of 493±391,  OC
244±144, EC 10±4, SO42~ 79±131 (13 day avg was only about 10% of the CAPs, but a spike
occurred during the first week), nitrate 39±67  ammonium 39±59, and urban dust (estimated from
Fe, Al, Ca, and Si) 18±6 (mean ± SD in ug/m3).

      Diesel Exhaust Particles

      Resuspended DE particles influences airway responses in mice with existing allergic
sensitization. A single 5-h nose-only exposure to 870 ug/m3 aerosolized filter-collected DE particles
(PM2 5) increased Mch-induced increases in ventilatory timing (Penh) in OVA sensitized/challenged
C57BL/6J mice (Farraj et al., 2006, 088469). Intranasal pretreatment with an antibody against the
pan neurotrophin receptor p75 attenuated the DE particle-induced increase in airflow obstruction,
indicating a role for neurotrophins. Neurotrophins are expressed by various structural, nerve and
immune cells within the respiratory tract and are linked to the etiology of asthma in both humans  and
animal models. DE particles alone in unsensitized mice caused a significant increase in lung
macrophages; this response was also inhibited  by anti-p75, which may suggest mediation of
macrophage influx by neurotrophin or alternatively may reflect anti-p75 dependent depletion of
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macrophages due to expression of the p75 receptor. Aside from increased macrophages, the single
exposure to DE particles had little effect on other markers of airway inflammation. In a similar
subsequent study, these authors demonstrate neurotrophin-mediated DE particle-induced airflow
obstruction in OVA sensitized and challenged BALB/c mice (Farraj  et al., 2006, 141730). in this
case using a  higher 2000 ug/m3 single 5-h exposure to aerosolized filter-collected PM2.5. Differences
between whole body plethysmography and tracheal ventilation measurements indicated that airflow
obstruction may have originated in the nasal passages. Again, very few indices of inflammation were
increased; however, similar neurotrophin-dependent increases in lung macrophages were observed
after DE particle exposure alone, and BALF IL-4 protein levels were increased 5-fold in sensitized,
challenged, DE particle-exposed mice. This neurotrophin-dependent IL-4 response was not evident
in the first study, and may be related to the higher dose used in the second study or the characteristic
allergic/Th2  bias of the BALB/c strain. Airflow obstruction in the absence of airway inflammation in
OVA-sensitized animals seen in both studies by Farraj et al. (2006, 088469; 2006, 141730) may
reflect DE particle-induced acute enhancement of neurogenic as opposed to immunologic
inflammation.

      Diesel Exhaust

      Exposure to relatively low doses of DE has been shown to exacerbate asthmatic responses in
OVA sensitized/challenged BALB/c mice (Matsumoto et al., 2006, 098017). Mice were intranasally
challenged one day prior to chamber exposure to DE (100 ug/m3 PM; CO, 3.5 ppm; NO2, 2.2 ppm;
SO2 <0.01 ppm) for 1 day or 1, 4, or 8 wk (7h/day, 5 days/wk, endpoints 12-h post-DE  exposure).
Results from the 8 wk study are described in Section 7.3.6.2. It should be noted that control mice
were left in a clean room as opposed to undergoing chamber exposure to filtered air. Significant
AHR upon Mch challenge was  observed after 1 and 4 wk of exposure, and airway sensitivity
(provocative concentration of Mch causing a 200% increase in Penh) was significantly  increased
after 1 wk of exposure but not 4 wk. DE had no effect on total cells in BALF, but transiently
increased expression of IL-4, IL-5, and IL-13  after 1 day of exposure, MDC after 1 wk, and
RANTES after 2 and 3 wk. Eotaxin, TARC, and MCP-1 were elevated without statistical
significance  after short-term (1  day or wk) exposure. Statistical power may have been lacking due to
few animals  in the exposure group (n=3). Protein levels of IL-4 and  RANTES were significantly
elevated after one day  of DE exposure. DE had no effect on OVA challenge-induced peribronchial
inflammatory or mucin positive cells. Therefore DE-induced AHR was observed in the absence of
neutrophilic  inflammation, similar to the responses described for aerosolized or nebulized DE
particles by Farraj et al. (2006,  088469; 2006, 141730) and Hao et al. (2003, 096565).

      Gasoline Exhaust

      Acute  exposure to fresh gasoline engine exhaust PM does not appear to exacerbate allergic
responses (Day  et al.,  2008, 190204). BALB/c mice were exposed to whole exhaust diluted 1:10
(H), 1:15 (M), or 1:90 (L), filtered exhaust at the 1:10 (HF),  or clean air for 6 h/day over three days.
Analytes for the high (H) and high filtered (HF) concentrations were: PM mass (ug/m3) 59.1±28.3
(H) and 2.3±2.6 (HF), PM number (particles/cm3) 5.0xl05 and l.lxlO4; CO (mg/m3) 102.8±33.0 and
99.5±1.6; NO (nig/m3) 18.4±2.8 and 17.2±1.9; NO2 (mg/m3) 1.4±0.3 and 1.7±0.2; SO2  (ug/m3)
1366.8±56.0 and 1051.1±43.0; NH3 (ug/m3) 1957.7±8.1 and 1241.5±6.1; NMHC (mg/m3) 15.9 and
25.9. Particles represented only 0.04% of the total exposure mass and particle size in the H exposure
ranged from 5.5 to  150 nm with the majority between 5-20 nm (MMD 150 nm) (McDonald et al.,
2008, 191978). Although particles were filtered out, it should be noted that NMHC (non-methane
volatile organics) increased by 62%. Mice were exposed with or without prior sensitization to OVA,
after one aerosol challenge and with or without secondary challenge. Acute gasoline engine exhaust
exposure had variable  effects on inflammatory and allergic markers  depending on the exposure
protocol, but there were no statistically significant differences between the H and HF exposure
results, suggesting that the PM fraction of gasoline engine exhaust does not appear to contribute
significantly to observed health effects.

      Hardwood Smoke

      One study indicated that hardwood smoke exposure only minimally exacerbated  indices of
allergic airway inflammation in an OVA-sensitized BALB/c mouse model and did not alter Thl/Th2
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cytokine levels (Barrett et al., 2006, 155677). Trend analysis indicated increasing BALF eosinophils
with increasing dose of hardwood smoke, becoming significantly elevated at 300 (ig/m3 (CO,
1.6±0.3 ppm; total vapor hydrocarbon, 0.6±0.2 ppm; NOX, below limit of quantitation, PM MMAD
0.35±2.0 (im), and increasing, but not significantly, OVA-specific IgE levels with hardwood smoke
up to 1,000 ug/m3.

      Model Particles

      Exposures to an aerosol of soot and iron oxide generated from ethylene (0.235 mg/m3 PM2.5)
were conducted to test whether the sequence of exposure to OVA aerosol challenge and PM affected
the observed response of OVA sensitized BALB/c mice (Last  et al., 2004, 097334). Though called
PM2.5, the authors characterized the PM material as UF, 80-110 nm, with the iron oxide crystals often
spatially segregated from the soot (200 (ig/m3 soot, remainder iron oxide, CO <0.8 ppm, NOX
<0.4 ppm, PAH below detection). Mice were exposed to PM via chamber inhalation for 2 wk
(4h/day, 3 days/wk) before or after 4 wk of OVA inhalation, or simultaneously to PM and OVA for
6 wk. Among endpoints (BALF cells, Penh, airway collagen, and goblet cells) only goblet cell
counts were significantly increased with PM exposure in any combination with OVA. There was a
trend toward increased Penh responses with exposure to PM alone or with OVA, particularly when
PM exposure immediately preceded Mch challenge (after or during OVA challenge). Results from
this study are difficult to interpret due to the varied elapsed times between cessation of PM or OVA
treatment and endpoint determination. The mild responses to  PM may be related to the
intraperitoneal sensitization protocol used, reputed to generate a highly allergic mouse  in which any
additive effects of PM may be obscured by maximal responses to antigen challenge (Deurloo et al.,
2001, 156396; Hao et al.. 2003. 096565).

      Res/cfua/0;7F/y/\s/7

      Arantes-Costa and colleagues (2008, 187137) estimated that 60 (ig of ROFA would be inhaled
by a mouse during one day of exposure to Sao Paulo air. This dose, given intranasally every other
day for 4 days, increased AHR in both nonsensitized and OVA sensitized/challenged BALB/c mice
upon Mch challenge 2 days after the last exposure. ROFA had no significant impact on eosinophil or
macrophage numbers in the lung, nor did it increase the chronic lung inflammation or thickening
induced by OVA. In many studies, particular effects such as airway obstruction are only evident
when allergic sensitization precedes exposure, but this study and a few others demonstrate allergen-
independent AHR after exposure to PM including CAPs (Lei et al., 2004, 087999) and DE or DE
particles (Hao et al., 2003, 096565; Li et al., 2007,155929).


      Allergy in Pregnancy or Early Life

      Pregnancy or in utero exposure may confer susceptibility to PM-induced asthmatic responses.
Exposure of pregnant BALB/c mice to aerosolized ROFA leachate by inhalation or to DE particles
intranasally increased asthma susceptibility in their offspring (Fedulov et al., 2008, 097482;
Hamada et al., 2007, 091235). The offspring from dams exposed for 30 min to 50 mg/mL ROFA 1,
3, or 5 days prior to delivery responded to OVA immunization and aerosol challenge with AHR and
increased antigen-specific IgE and IgGl antibodies. AHR was also observed in the offspring of dams
intranasally instilled with 50 (ig of DE particles or TiO2, or 250 (ig CB, indicating that  the same
effect could be demonstrated using relatively "inert" particles. Pregnant mice were particularly
sensitive to exposure to DE particles or TiO2 particles, and genetic analysis indicated differential
expression of 80 genes in response to TiO2 on the pregnant background. Thus pregnancy  may
enhance responses to PM, and exposure to even relatively inert particles may result in offspring
predisposed to asthma.


      Allergic Sensitization

      A large number of in vivo animal studies and in vitro studies have demonstrated  that particles
can alter the immune response to challenge with specific antigens and suggest that PM acts as an
adjuvant to promote allergic sensitization. This phenomenon was introduced in the 2002 Diesel
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Document, and has been noted in multiple animal and human studies by the 2004 PM AQCD
(U.S. EPA, 2004, 056905). Adjuvants enhance the immune response to antigens through various
means, including chemoattraction, cytokines, or enhanced antigen presentation and costimulation,
and may act on a number of cell types. Importantly, adjuvants may be major contributors to the
development of inappropriate immune responses. These immune responses, mediated by T helper
cells, fall along a continuum from T helper type 1  (Thl) to T helper type 2 (Th2). Thl responses,
characterized by IFN-y, are inflammatory and in excess can lead to tissue damage. Alternatively, Th2
responses  are characterized by IL-4, IL-5, IL-13, eosinophils, and IgE, and are associated with
allergy and asthma. Autoimmune diseases may be driven by Thl, Th2, or mixed responses, but
allergic diseases are predominantly Th2 mediated, and many of the immunologic effects observed
for PM fall into the Th2 category.
      It has been suggested that the capacity of particles to enhance allergic sensitization is
associated more strongly with particle number and surface area than particle mass, and several
studies comparing size fractions of the same material show greater adjuvant activity for an
equivalent mass dose of smaller particles (de Haar et al., 2006, 144746; Inoue et al., 2005, 088625;
Nygaard et al., 2004, 058558). This is particularly true of inert or homogeneous materials, such as
carbon, polystyrene, and TiO2, which vary little in composition with size fraction. Studies using
CAPs have also observed that adjuvancy and allergic exacerbation are more strongly associated with
the UF fraction, possibly due to greater oxidative potential (Kleinman et al., 2005,  087880;
Kleinman et al., 2007, 097082; Li et al., 2009, 190457). In some studies of ambient PM, however,
PMio_25 or PMio have demonstrated equal or greater adjuvancy compared to PM25 (Nygaard et al.,
2004, 058558; Steerenberg et al., 2004, 096024; Steerenberg et al., 2005, 088649). More inhalation
studies to compare size fractions are needed in order to elucidate the role of particle size in
mediating adjuvancy, but this may prove difficult given the influence of composition, e.g.,
combustion related materials (Steerenberg et al., 2006, 088249) and metal content (Gavett et al.,
2003, 053153). which differs among various size fractions and sources.

      CAPs

      As little  as 0.1 (ig of UF Los Angeles CAPs administered intranasally with OVA was able to
significantly boost allergic antibody responses in BALB/c mice (Li et al., 2009, 190457). A
comparison of UFPs (aerodynamic diameter <0.15 um) with a mix of sub-2.5  urn particles
(PM2.5/UFP) collected 200 m from a major freeway delivered intranasally five times over the course
of nine days showed that UFP but not PM2.5/UFP were associated with significant adjuvant effects.
0.5 ug of UFP  with OVA (but not alone) led to an increase in BALF eosinophils, allergic cytokines,
inflammatory mediators, and serum OVA-specific IgE/IgGl, as well as allergic tissue inflammation
in the upper and lower airways. Adjuvant effects of UFP were observed with two independently
collected samples (1/2007 and 9/2006) and could not be replicated by administering the same
amount of endotoxin measured in the particles, indicating that the effects were not unique to the
sampling period nor mediated by contaminating endotoxin. UFP had  a greater OC and PAH content
than PM2.5/UFP, and induced greater oxidative stress in vitro. Partial blocking of the adjuvant effects
by antioxidant administration implicates redox potential as  a key factor in mediating these effects.
The authors suggest that the lack of adjuvancy for UF carbon particles (being  mostly EC) is due to a
lack  of redox cycling compounds, but this was not tested. In contrast, UF (30-50 nm) CB particles
have demonstrated intranasal adjuvant activity in other studies (de  et al., 2005, 097872) when
administered with OVA over three consecutive days. A 200-ug dose increased serum OVA-specific
IgE,  local  lymph node dendritic cells and OVA-specific Th2 lymphocytes in the lung draining lymph
nodes and lung, as well as post-challenge airway eosinophilia. Doses as low as 20 ug were able to
activate adoptively transferred OVA-specific T cells.

      Diesel Exhaust Particles

      Resuspended DE particles have been shown to enhance OVA-specific IgGl and IgE in
BALB/c mice exposed via inhalation to doses as low as 200 and 600  ug/m3, respectively (Whitekus
et al., 2002, 157142). Mice were exposed to DE particles (200, 600 and 2,000 ug/m3) for 1 h daily
for 10 days prior to aerosol OVA challenge. Compared with responses to OVA alone, antibody levels
were increased by all OVA+DE particle exposures. Statistical significance was reached for IgGl at
all DE particle exposure levels, whereas OVA specific IgE was significantly increased at the 600 and
2,000 ug/m3 doses and total IgE was significantly elevated  at 2,000 ug/m3. Although strong adjuvant
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 effects were observed, no general markers of inflammation such as eosinophils, IL-5, GM-CSF,
 mucin, morphological changes, or eosinophilic major basic protein (MBP) deposition in the airways
 were observed in exposed mice. In vitro experiments using the RAW 264.7 macrophage-like cell line
 indicated a DE particle-induced lipid peroxidation and protein oxidation, which could be inhibited
 by a variety of antioxidants. Also observed was a decrease in the GSH:GSSG ratio and an increase in
 HO-1 expression, both of which were inhibited only by the thiol antioxidants NAC and BUG. These
 same thiol antioxidants were able to completely block DE particle-related increases in IgE and IgGl,
 as well as lipid peroxides and oxidized proteins recovered from BALF at the 2,000 (ig/m3 dose. Thus
 solid correlations between in vivo and in vitro antioxidant activities were found, and the reversal of
 adjuvant effects by antioxidants in vivo clearly indicates a link between oxidative stress and DE
 particle adjuvancy. However, the intranasal adjuvant activity of Ottawa, Canada, dust (EHC-93) in
 the same strain of mice was not inhibited by NAC pretreatment (Steerenberg et al., 2004, 087981).
 suggesting that disparate pathways may be utilized by different materials to exert immune
 stimulation.

      Diesel Exhaust

      DE inhalation during allergen exposure has been shown to augment IgE production and alter
 methylation of T helper genes in BALB/c mice (Liu et al., 2008, 156709) Animals were exposed to
 DE (1280 (ig/m3 PM) over a 3-wk period, 5 h per day, concurrent with periodic intranasal
 sensitization to the common fungus Aspergillus fumigatus. Gas concentrations were not reported.
 Total IgE and BALF  eosinophils were elevated with A. fumigatus sensitization and further increased
 by concomitant DE exposure. Greater methylation of the IFN-y promoter was observed following
 DE and A. fumigatus exposure (but not DE alone) compared to A. fumigatus alone, indicating that
 combined DE and allergen exposure might induce methylation and thus suppress expression of Thl
 genes. Furthermore, hypomethylation of the IL-4 promoter was detected after exposure to A.
fumigatus and DE compared with exposure to A. fumigatus or DE alone, suggesting pro-allergic Th2
 gene activation upon combined exposure to allergen and DE. The changes  in methylation status of
 these genes were associated with alterations in IgE levels in individual animals, indicating that
 modifications at the genetic level could result in predicted downstream effects. This study shows for
 the first time that DE exposure can exert pro-allergic in vivo effects on the mouse immune system at
 the epigenetic level.
      A toxicogenomic approach to investigate early response mechanisms of DE adjuvancy was
 taken by Stevens et al. (2008, 157010). BALB/c mice were chamber exposed to filtered air, 500 or
 2,000 (ig/m3 PM in DE for 4 h/day over 5  consecutive days and intranasally exposed to OVA on each
 of the first 3 days. In the low (500 (ig/m3) vs. high (2,000 (ig/m3) DE exposures, CO, NO, NO2, and
 SO2 were <0.1 versus 4.3, <2.5 vs. 9.2, <0.25 vs. 1.1 and <0.06 vs. 0.2 ppm; particle number median
 diameters were 80 and 86 nm, and volume median diameters were  184 and 195 nm, respectively.
 Lung tissues were assessed for alterations in global gene expression (n = 4) 4 h after the last DE
 exposure on day 4. Mice were intranasally challenged with OVA or saline on day 18 and then with
 OVA on day 28.  Post-challenge results demonstrated mild adjuvancy with antigen and DE exposure
 as evidenced by significant increases in eosinophils, neutrophils, lymphocytes, and IL-6 in the
 BALF. Antibody responses were not significantly affected by DE exposure, although a slight
 increase in IgE after high concentration exposure was observed. DE alone only increased
 neutrophils, indicating the need for combined exposure to DE and antigen in the development of
 allergic outcomes.  Comparison of low DE /OVA vs. air/OVA resulted in no significant changes  in
 gene sets associated with this treatment. Comparison of the high DE/OVA versus air/OVA, however,
 showed significant changes in 23 gene sets, including neutrophil homing and other chemokines,
 inflammatory cytokines, numerous interleukins and TNF subtypes, and growth/differentiation
 pathways.


      Summary of lexicological  Study Findings for Allergic Responses

      Studies conducted since the last review confirm and extend the 2004 PM AQCD's  (U.S. EPA,
 2004, 056905) finding that PM can modulate immune reactivity in both humans and animals to
 promote allergic sensitization and  exacerbate allergic responses. Numerous forms of PM, including
 inert materials, have been shown to function as adjuvants, and although toxicological studies of
 relatively homogeneous materials  demonstrate greater adjuvancy for smaller particles, some analyses
 December 2009                                 6-128

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of ambient PM do not. Recent toxicological studies comparing size fractions of well-characterized
ambient PM for adjuvant activity in a direct, controlled fashion via inhalation exposure suggest a
role for oxidative potential, but thus far the relative contributions of size and composition are not
entirely clear. Although epidemiologic studies examining specific allergic outcomes and short-term
exposure PM are relatively rare, the available studies, conducted primarily in Europe, positively
associate various PM size fractions with allergic rhinitis. Similar findings from a number of long
term studies are described  in Chapter 7.


6.3.7.   Host Defense

      The normal and very important role of respiratory immune defense is  the detection and/or
destruction of pathogens that enter the lung via inhalation and removal of damaged, transformed
(cancerous), or infected cells. Innate immune defenses of the respiratory tract include mucociliary
clearance, release of toxic  antimicrobial proteins into airway surface liquid,  and  activation of
alveolar macrophages. The innate immune system is the earliest responder to irritation or infection,
initiating the normal inflammatory response including the majority of detrimental inflammatory
processes discussed. Activated macrophages and epithelial cells release cytokines and chemokines
that can bring into play the adaptive immune system, which in turn can produce  long-lasting
pathogen-specific immune responses critical for resolving and preventing infections.


6.3.7.1.   Epidemiologic Studies

      Collectively, results  from multicity studies of hospital admissions and ED visits for respiratory
infection as well as single-city studies conducted in the U.S. and Canada (summarized in Figure
6-14) show a positive association between PM and respiratory infections. Lag structure was not
investigated in most studies and effects have been observed in association with current day
concentration (Zanobetti and Schwartz, 2006, 090195) as well as with concentrations modeled using
a 14-day  distributed lag function (Peel et al., 2005, 056305). Of studies examining multiple lag
times, associations with increasing lag times were observed (Dominici et al., 2006, 088398; Peel  et
al., 2005, 056305; Peng  et al., 2008, 156850). Although no significant positive associations were
reported, Slaughter et al. (2005,  073854) observed a trend of increasing association with increasing
lag for acute respiratory infection ED visits with PMb PM2.5, PMi0 and PMi0_2.5.  This delay in the
onset of disease may reflect the time necessary for an infection to become established and
symptomatic. The majority of toxicological  evidence, described below and in the 2004 PM AQCD
(U.S. EPA, 2004, 056905). suggests that PM impairs innate immunity, the first line of defense in
preventing infection.


6.3.7.2.   Toxicological  Studies

      Several toxicological studies were cited in the 2004 PM AQCD (U.S.  EPA, 2004, 056905) that
demonstrated increased susceptibility to infectious agents following exposure to PM. A limited
number of new studies have evaluated the effect of PM on host defense in rodents. Two recent
studies have observed an increase in susceptibility to influenza infection and respiratory syncytial
virus in mice. However, one new study found that wood smoke had no effect on bacterial clearance
in rodents.


      Bacterial Infection

      Several studies included in the 2004 PM AQCD (U.S. EPA, 2004, 056905) demonstrated
increased susceptibility to  infectious agents following exposure to various forms of PM. CAPs
exposed aged rats demonstrated increased S. pneumoniae burdens when a 24-h exposure (65 (ig/m3)
followed infection (Zelikoff et al., 2003, 039009). In another study, IT instillation exposure to
ROFA was found to affect  bacterial clearance (Antonini et al., 2002, 035342). Examinations of
mechanisms related to PM interference with host defenses have demonstrated impaired mucociliary
clearance and modified macrophage phagocytosis and chemotaxis. Prolonged exposure to  inhaled
particles at sufficiently high concentrations can lead to diminished clearance of PM from the alveolar
December 2009                                 6-129

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region of the lung, resulting in the accumulation of retained particles and an accompanying chronic
alveolar inflammation. Diminished clearance of PM may also increase susceptibility to pulmonary
infection by impeding clearance of pathogens. Impaired phagocytosis by alveolar macrophages may
contribute to a decrease in the lung's capacity to deal with increased particle loads (as occurs during
high-pollution episodes) or infections and affect the local and systemic responses through the release
of biologically active compounds (cytokines, ROS, NO, isoprostanes).

      Diesel Exhaust

      Since the last review, several additional studies have reported impairment of pathogen
clearance following exposure to various sources of PM. All levels of DE (30, 100, 300 or 1,000
ug/m3) decreased lung bacterial clearance in C57BL/6 mice exposed for 1 wk (7 days/wk, 6 h/day)
prior to infection with Pseudomonas aeruginosa (Harrod et al., 2005, 088144). This  effect appeared
concentration dependent up to 100 ug/m3 and was not enhanced at higher concentrations. Lung
inflammation was not induced by DE in the absence of infection, but infection-induced inflammation
was exacerbated by DE at all concentrations without apparent concentration dependency. Measures
of histopathology in infected animals were increased by DE exposure in a concentration-dependent
manner, peaking at 100 ug/m3 and leveling off or decreasing with higher concentrations. Particle
deposition was readily apparent in the lungs after exposure to the lowest concentration of 30 ug/m3.
A loss of ciliated cells was observed  at 30 ug/m3 and 100 ug/m3 in large airways and in small
airways at the higher concentration. Alterations in Clara cell morphology and function were
observed at both concentrations as well. Concentrations of gases were reported to be  2.0-45.3 ppm
NO, 0.2-4.0 ppm NO2, 1.5-29.8 ppm CO and 8-365 ppb for SO2 (McDonald  et al., 2004, 055644).
PM mass median diameter was -100-150 nm at all exposure levels (>90% below 1 urn in
aerodynamic diameter), with lower exposure concentrations having a slightly smaller size
distribution (Reed et al., 2004, 055625).

      Gasoline Exhaust

      In a study by Reed et al. (2008, 156903). short or long-term exposure to fresh gasoline exhaust
(6h/day, 7day/wk for 1 wk or 6 mo) did not affect clearance of P. aeruginosa from the lungs of
C57BL/6 mice. Atmospheric characterizations are described above for the Day et al. (2008, 190204)
and McDonald et al. (2008, 191978) studies in Section 6.3.6.3.

      Hardwood Smoke

      Similar to gasoline exhaust, hardwood smoke does not appear to have significant impact on
pathogen clearance.  C57BL/6 mice were exposed to 30-1,000 ug/m3 hardwood smoke by whole-
body inhalation for 1 wk and 6  months (Reed  et al., 2006, 156043). Long-term responses are
discussed in Sections 7.3.3.2 and  7.3.7.2. Concentrations of gases ranged from 229.0-14,887.6
mg/m3 for CO, 54.9-139.3 ug/m3  for ammonia, and 177.6-3,455.0 ug/m3 for nonmethane volatile
organic carbon in these exposures. Bacterial clearance of instilled P. aeruginosa was unaffected by
hardwood smoke.

      Intratracheal Instillation

      Studies demonstrate that  ROFA impairs host defenses and that soluble metals are important
contributors. Antonini et al. (2004, 097199) compared sources of ROFA in SD rats. Precipitator
ROFA induced an inflammatory response and diminished pulmonary clearance of L. monocytogenes
while air heater ROFA had no effect  on lung bacterial clearance at the same IT dose of 1 mg/lOOg
body weight. Precipitator ROFA generated a metal-dependent hydroxyl radical suggesting that
differences in metal  composition were a determinant of the immunotoxicity of ROFA. Subsequent
studies using soluble extracts of ROFA with or without a chelating agent confirmed that soluble
metals were responsible for weakening defenses against bacterial infection and impairing both innate
and adaptive lung immune responses (Roberts et al., 2004, 196994; Roberts  et al., 2007, 097623)
ROFA has also been shown to result in ciliated cell loss in BALB/c mice after intranasal
administration of 60 ug every other day for 4 days (Arantes-Costa  et al., 2008, 187137).
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      Viral Infection
      Diesel Exhaust

      Viral respiratory infections in early life are associated with increased incidence of childhood
asthma and other pulmonary diseases. DE exposure can enhance the progression of influenza
infection. BALB/c mice that were chamber exposed to DE 4 h/day for 5 days and subsequently IT
instilled with influenza A/Bangkok/1/79 virus had increased susceptibility to influenza infection
(Ciencewicki et al, 2007, 096557). Exposures to two concentrations of DE were conducted:
500 ng/m3 (0.9 ppm CO, O.25 ppmNO2, <2.5 ppmNO, and 0.06 ppm SO2) and 2,000 (ig/m3
(5.4 ppm CO, 1.13 ppmNO2, 10.8 ppm NO, and 0.32 ppm SO2). Responses were greater for animals
exposed to 500 (ig/m DE than to 2,000 (ig/m3, and were associated with a significant increase in
IL-6 protein and mRNA expression and IFN-J3 expression. The authors present the possibility that
damage to the epithelium at the higher exposure prevented viral infection and replication. After
exposure to 500 (ig/m3 DE alone or prior to infection, decreased expression of surfactant proteins
(SP) A and D was observed. These proteins are part of the IFN-independent defense against
influenza.
      Similarly, Harrod et al. (2003, 097046) demonstrated decreased SP-A expression in the lungs
following DE exposure and linked it to increased susceptibility to respiratory syncytial virus (RSV),
the most common cause of respiratory infection in young children. C57BL/6 mice, a relatively
RSV-resistant strain, were exposed via inhalation to DE at a concentration of 30 or 1,000 (ig/m3 PM
6h/day for 7 consecutive days prior to intratracheal viral inoculation. Gaseous copollutants ranged
from 2.0-43.3 ppm for NOX (~ 90% NO), 0.94-29.0 ppm CO, and 8.3-364.9 ppb SO2. Exposure to
30 (ig/m3 DE did not induce a statistically significant increase in BALF cell numbers compared to
air-treated, infected animals. However, distinct consolidated inflammatory infiltrates were observed
in the peribronchial regions of RSV-infected animals  exposed to this concentration, along with
alterations in Clara cell morphology, decreased CCSP production by these cells, and occasional
regional myofibril layer thickening. These changes were more pronounced in RSV-infected animals
exposed to 1000 (ig/m3, and the higher concentration  also resulted in significant increases in
inflammatory cells, predominantly macrophages, in both uninfected and infected mice compared to
air-exposed controls. Both doses elicited significant levels of TNF-a and IFN-y in the lungs of
infected animals, but decreased levels of SP-A. Consistent with this study's finding of decreased
SP-A and increased viral gene and inflammatory cytokine expression after DE  exposure, SP-A"7"
mice demonstrate decreased clearance of RSV concordant with increased lung  inflammation (Levine
et al., 1999, 156687). Thus, DE may enhance susceptibility to  respiratory viral  infections by
reducing the expression and production of SP (Ciencewicki et al., 2007, 096557; Harrod et al.,
2003, 097046). although the contribution of gaseous copollutants, in some instances concentrated
1,000 times, should be considered for both studies. SP are also essential for clearance of other
pathogens, including group B Streptococcus (GBS), Haemophilus influenzcte, and P. aeruginosa
(LeVine and Whitsett, 2001, 155928).
      A reduction in host defense molecules and an increase in viral entry sites was observed by
Gowdy et al. (2008,  097226) after BALB/c mice were exposed to HEPA filtered room air or DE at
0.5 or 2.0 mg/m3 for 4hr/day for one or five consecutive days [O2 (%) 21.0±0.10 or 20.7±0.09, CO
(ppm) 1.7±0.15 or 5.4±0.07, NOX (ppm) 2.0±0.36 or  7.4±0.61, SO2 (ppm) 0.0±0.0 or 0.4±0.3,
number median (nm) 96.2±2 or 97±2, volume median (nm) 238±2 or 249±2, OC/EC (wt ratio)
0.4±0.04 or 0.4±0.07 for the 0.5 or 2.0 mg/m3 exposures, respectively]. One of the more notable
features of this study was the observation that effects  of extended exposure to the lower
concentration (0.5 mg/m3 for 5 days) tended to persist beyond 18 h post-exposure. Exposure to  DE
significantly increased BALF neutrophils in the higher exposure group, and this response persisted
beyond 18 h only after the five day exposure. An increase in ICAM-1 expression (a viral entry site)
was observed in both exposure groups, and was persistent in the lower  concentration group after a
5-day exposure. Persistently elevated expression of pro-inflammatory cytokines IL-6 and TNF-a and
pro-allergic cytokine IL-13 was observed after five days of low concentration exposure. Non-
statistically significant effects of either concentration or exposure regimen included increased IFN-y
and MIP-2. Host defense molecules CCSP, SP-A and SP-D were decreased after either exposure
regimen, persisting beyond  18 h in the low concentration group.
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      Taken together, these data suggest that exposure to DE can weaken host defenses, in some
cases persistently. A role for PM in these responses is supported by studies demonstrating changes in
host defense molecules and viral entry sites in vitro consistent with those observed in vivo. In lung
epithelial cells, DE particles increased the mRNA expression of 1C AM-1, LDL and
platelet-activating factor (PAF) receptors, which can act as receptors for viruses or bacteria (Ito et
al., 2006, 096648). DE particles may therefore enhance the susceptibility to infection by the
upregulation of bacterial and viral invasion sites in the lungs. Expression of the (3-defensin-2 gene,
which is one antimicrobial mechanism of host defense in the airway, was significantly inhibited by V
and not Ni or Fe in airway epithelial cells incubated with aqueous leachate of ROFA (Klein-Patel et
al., 2006, 097092).


      Immunosuppressive Effects of PM


      Diesel Exhaust

      DE may affect systemic immunity. Decreased thymus weight was observed in female F344
rats exposed to 300 ug/m3 DE for  1 wk by Reed et al. (2004, 055625). Concentrations of gases for
this PM concentration were reported to be approximately 16.1 ppm for NO, 0.8 ppm for NO2,
9.8 ppm for CO, and 115 ppb for SO2. Long-term responses are discussed in Section 7.3.8.


      Summary of lexicological Study Findings for Host Defense

      Toxicological studies demonstrate that short-term inhalation exposures to CAPs and DE, but
not gasoline exhaust or wood smoke,  can increase susceptibility to infection by bacterial and viral
pathogens. While gaseous  copollutants may be contributing factors, a role for particles is
demonstrated by studies utilizing IT instillation exposure and in vitro studies of PM where
biomarkers parallel those observed in vivo. Although ethical considerations limit controlled exposure
studies in humans, epidemiologic evidence reflects an association between most PM size fractions
and hospital admissions for respiratory infections. Importantly, toxicological studies demonstrate
impaired host defense against the etiological agents of influenza, pneumonia (S. pneumoniae), and
bronchiolitis (RSV), which are commonly reported respiratory morbidities associated with PM.


6.3.8.  Respiratory  ED  Visits, Hospital Admissions and  Physician Visits

      The epidemiologic evidence presented in the 2004 PM AQCD (U.S. EPA, 2004, 056905)
linking short-term increases in PM concentration with respiratory hospitalizations and ED visits was
consistent across studies. Recent investigations  provide further support for this relationship, with
larger effect estimates observed among children and older adults. However, effect estimates are
clearly heterogeneous, with evidence  of both regional and seasonal differences at play.
      Excess risk estimates for hospitalizations or ED visits for all respiratory diseases combined,
reported in studies reviewed in the 2004 PM AQCD (U.S. EPA, 2004, 056905) fell within the range
of approximately 1-4% per 10 ug/m3 increase in PMi0. On average,  excess risks for asthma were
higher than excess risks for COPD and pneumonia. Associations with PM2.5  (including PMi) and
PM10_2.5 were also reported in the limited body of evidence reviewed in the 2004 AQCD. Excess  risk
estimates fell within the range of approximately 2.0-6.0% per 10 ug/m3 increases in PM2.5 or PMi0_2.5
for all respiratory  diseases combined as well as  COPD admissions. Larger estimates were reported
for asthma admissions. Many of the associations of respiratory admissions and ED visits with
short-term PM2 5 concentration were statistically significant. The associations with PMi0_2.5 were less
precise with fewer reaching statistical significance (U.S. EPA, 2004, 056905). Finally, several
studies reviewed in the 2004  AQCD reported associations of PM with outpatient physician visits,
suggesting that the population impacted by short-term increases in PM is not restricted to  those
admitted to the hospital or seeking medical attention through an ED.
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Table 6-13.   Description of ICD-9 and ICD-10 codes for diseases of the respiratory system.
       Description
             ICD 9 Codes
ICD 10 Codes
Diseases of the Respiratory System  460-519
                                                            JOO-J99
Asthma
                       493
                                                            J45
COPD and allied conditions
490-496 (asthma, chronic bronchitis, emphysema,
bronchiectasis, extrinsic allergic alveolitis)
Chronic lower respiratory diseases
                                     J40-J47 (bronchitis, emphysema, other COPD, asthma, status
                                     asthmaticus, bronchiectasis)
Acute Respiratory Infections
460-466 (common cold, sinusitis, pharyngitis, tonsillitis,
laryngitis & tracheitis, bronchitis & bronchiolitis)
Acute Upper Respiratory Infections
                                     JOO-J06 (common cold, sinusitis, pharyngitis, tonsillitis,
                                     laryngitis & tracheitis, croup & epiglottitis)
Acute bronchitis and bronchiolitis
                       466
                                                            J20-J22
Allergic Rhinitis
                       477
                                                            J30.1
Pneumonia
                       480-486
                                                            J13-J18
Wheezing
                       786.09
      Hospital admissions or ED visits for respiratory diseases and ambient concentrations of PM
have been the subject of more than 90 peer-reviewed research publications since 2002 (Annex E).
Included among these new publications are several large single-city and multicity studies. These new
studies complement those reviewed in the 2004 AQCD by examining the effect of several PM size
fractions and components on increasingly specific disease endpoints, as well as evaluating the
presence of effect modification by factors such as season and region.
      Specific design and methodological considerations of the large and multicity studies included
in this review were discussed previously (Section 6.2.10). Like the  CVD endpoints discussed, the
respiratory endpoints examined in these studies were heterogeneous and approaches to selecting
cases for inclusion in the studies were varied. ICD codes commonly used in hospital admission and
ED visits studies for diseases of the respiratory system are found in Table 6-13.


6.3.8.1.   All Respiratory Diseases

      Findings from new studies  of PM and respiratory hospitalization and ED visits among children
are summarized in Figure 6-10. Results from new studies of adults are summarized in Figure 6-11.
Information on the PM concentrations during the relevant study periods is found in Table 6-14.


      Children

      Barnett et al. (2005, 087394) used a case-crossover design to study respiratory hospital
admissions (ICD-9 460-519) of children (age groups 0, 1-4, and 5-14 yr) in seven cities in Australia
and New Zealand from 1998 to 2001. All respiratory diseases (ICD 10 JOO-J99) except Mendelson's
Syndrome, post-procedural disorders, asphyxia and  certain other symptoms (ICD 10 codes
J95.4-J95.9, R09.1, R09.8) were included in the study. In addition, scheduled admissions and
transfers from other hospitals were excluded.  Using an a priori lag (0- to 1-day avg), increases in
respiratory hospital admissions of 2.0% (95% CI: -0.13 to 4.3) among infants <1 yr old, 2.3%
(95% CI:  1.9-7.3) among children 1-4 yr old and 2.5% (95% CI: 0.1-5.1) among children 5-14 yr old
per 10 ug/m3 increase in 24-h avg PM10 were  observed. Increases of 6.4% (95% CI: 2.7-10.3) among
infants <1 yr and 4.5% (95% CI:  1.9-7.3) among children 1-4 yr per 10  ug/m3 increase in PM2.5 were
observed.
      Ostro et al. (2009,  191971) studied the effect of PM2.5 and components on respiratory disease
(ICD9 460-519) hospitalizations among children <19 yr from 2000 to 2003 in six  counties in
California. The nine components  examined (EC,  OC, nitrates, sulfates, Cu, Fe, K, Si and Zn), were
chosen because they made up relatively large proportion of PM2.5, had a signal to noise ratio >2, or
December 2009
                        6-133

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the majority of their values were greater than the level of detection. Single day lags of 0-3 days were
evaluated. The largest risks were observed at lag 3 days for PM25 (2.8% [95%CI: 1.2-4.3] per 10
(ig/m3), EC (5.4% [95% CI: 0.8-10.3] per IQR) and Fe (4.7% [95% CI: 2.2-7.2] per IQR increase).
Although not as great, positive associations were also observed for OC, SO42~, nitrate, Cu and Zn.
      In a study of PM2.5 from wildfires in California during 2003, Delfino et al. (2009, 191994)
evaluated conducted stratified analyses comparing PM2.5 associations pre-, post- and during the
wildfires. Four age groups (0-4, 5-19, 20-64 and >65 yr) were considered in these analyses. Authors
found increased respiratory disease admissions in the periods before (2.6% [95%CI: -5.4 to 11.3])
and during (2.7% [95%CI: -1.6 to 7.6]) the wildfires among children 5-19 yr old, but not after the
wildfire period. Among younger children (0-4 yr), hospital admissions were increased during fire
periods (4.5% [95% CI: 1-8.2]), but not before or after the wildfire period. Estimated zip code level
PM2.5 concentrations were 90 (ig/m3 and 75 (ig/m3 during  heavy and light smoke conditions,
respectively, compared to 20 (ig/m3 during non-fire periods.
      In the study of six cities in France described previously (PSAS), investigators report a change
of 0.4% (95%CI:  -1.2  to 2) per 10 ug/m3 increases in PM25 for all respiratory diseases combined
(ICD-10: JOO-J99) among children from 0-14 yr old (Host et al., 2008, 155852). The same study
reported a larger increase associated with PMi0_2.5 of 6.2% (95% CI: 0.4-12.3, 0-1 day  avg) per
10 ug/m3 increase among children. A relatively large effect for PMio_2.s (31% [95% CI: -4.7 to 80])
was also observed in a single-city study of children <3 yr  in Vancouver (Yang  et al., 2004, 087488).
The non-significant PM2 5 effect estimates were  not presented in the publication. Luginaah et al.
(2005, 057327) did not observe significant increases in respiratory hospitalizations with increasing
PMio concentrations among male or female children in Ontario Canada, while Ulirsch et al. (2007,
091332) reported increased admissions for respiratory hospitalizations, ED and urgent care visits
combined among children <17 yr in association  with PMi0.
      As shown in Figure 6-10, studies of respiratory hospitalizations or ED visits reported
increased risks to children in association with all size fractions. However, increased risk among boys
was not observed in Ontario (Luginaah et al., 2005, 057327). Estimates are imprecise and it is not
clear if associations with PM2 5, PMi0_2.5, or both are driving associations observed with PMi0.
Study
                   Location
Lag    Age
Effect Estimate (95% CI)
Barnettetal. (2005.087394) Australia/NZ 0-1
Host et al. (2008, 1 55852) 6 Cities France 0-1
Ostro etal. (2009,191971) 6 Counties CA 3
Delfino etal. (2009. 190254) 6 Counties, CA 0-1
(wildfires)
Host et al. (2008, 1 55852) 6 Cities France 0-1
Yang etal. (2004, 087488) Vancouver
Barnettetal. (2005.087394) Au/NZ 0-1
0-1
0-1
Ulirsch et al. (2007, 091332)* 2 Cities, SE Idaho 0
Luginaah et al. (2005. 057327) Windsor, Can 1
2
3
1
2
3
"Hospital admissions, ED and urgent care visits combined
1-4
C -I / 	

0-19
0-4
5-19
14
<3 (31% (-4.7 to 80)^
1-4 J
5-14
0-17
0-1 4 Females
D-1 4 Females

0-1 4 Males •
014 Male" 4 	 »



_ "
_



PMio
_



^





i i I i i i i
-4 -2 Q 2 4 6 8
Excess Risk (%)
Figure 6-10.   Excess risk estimates per 10 ug/m3 24-h avg PM2.5, PM10.2.5, and PM10
              concentration for ED visits and HAs for respiratory diseases in children. Studies
              represented in the figure include all multicity studies as well as single-city
              studies conducted in the U.S. or Canada.
December 2009
6-134

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      Adults and All Ages Combined

      In the study of four million ED visits from 31 hospitals in Atlanta described previously,
SOPHIA investigators reported an excess risk of 1.3% (95% CI: 0.4-2.1, lag 0-2) per 10 ug/m3
increase in 24-h avg PM10 for ED visits for respiratory causes combined (ICD-9: 460-466, 477,
480-486, 491-493, 496, 786.09) among all ages during January 1993-August 2000 (Peel et al., 2005,
056305). PM2.5, PMio_2.5, UF number count and PM2 5 components (SO42~, acidity, EC, OC, and an
index of water-soluble transition metals) were available for inclusion in analyses beginning August
1, 1998. Excess risks of 1.6% (95% CI: -0.003 to 3.5) per 10 ug/m3 increase in 24-h avg PM2.5 and
0.6% (95% CI: -3.6 to 5.1) per 10 ug/m3 increase in PMio-2.5 were reported. Weaker, less precise
associations with components were reported and no increase with UF PNC was observed.
      Analyses with four additional years of data were conducted and more recently reported by
SOPHIA investigators (Tolbert  et al., 2007, 090316). Single-pollutant results are included in Figure
6-11. The effect of PMi0 remained with the additional years of data, while the effect of PM2.5 was
diminished and a decrease in ED visits with PMi0_2.5 was observed. The association of PMi0 with
respiratory disease ED visits was robust to adjustment for O3, CO and NO2. In another recent
analysis using SOPHIA data from 1998 through 2002 to compare source apportionment methods,
Sarnat et al.  (2008, 097972) reported that PM2 5 from mobile sources, PM2 5 from biomass burning
and SO42~-rich secondary PM2 5 were associated with respiratory ED visits and associations were
robust to the choice of the method. Excess risks were statistically significant, ranging from
approximately 2-4%, depending on the method.
      In a French multicity study, larger increases were observed in association with 24-h avg
PMio_2.5 concentration compared to PM2 5 concentration among adults as well as children. Among
adults 15-64 yr, investigators reported increases in respiratory hospitalizations of 0.8% (95%CI:
-0.7 to 2.3) and 2.6% (95%CI: -0.5 to 5.8) per 10 ug/m3 for PM25 and PM10_25, respectively (lag
0-1 days) (Host et al., 2008, 155852).
      In a study of respiratory hospital admission and ED visits (ICD-9 Codes 460-519) among all
ages conducted in Spokane, Washington, no associations were observed with any size fraction of PM
considered (e.g., PMi, PM25, PM10_2.5, PM10) (Slaughter  et al., 2005, 073854). Furthermore, several
of the same investigators conducted a source apportionment analysis using daily PM25 filter samples
from the same residential monitor in Spokane (Schreuder et al., 2006, 097959). In this investigation,
PM2 5 from vegetative burning in the previous day (lag 1) was associated with respiratory hospital
admissions (2.3% [95% CI: 0.9-3.8] per interquartile range increase in the source marker). In a study
of PM25 from wildfires in California during 2003, associations with respiratory hospitalizations were
generally stronger relative to associations in the periods before and after the fires (Delfino  et al.,
2009, 191994). Among adults 20-64 yr, an increase  of 2.4% (95% CI: 0.5-4.4 per 10 ug/m3) was
reported during the wildfire period compared to 0.9% (95%CI: -0.1 to 1.8 per 10  ug/m ) for all
periods combined (pre-, post- and during wildfires).
      Luginaah et al. (2005,  057327) examined respiratory hospital admissions in relation to PMi0
concentration across strata for age and gender and compared time series to case-crossover
approaches.  The results for all ages combined, which were relatively precise, stratified by gender and
all lags are presented in Figure 6-11; the largest estimates for PMi0 were for adult males (15-64 yr
old). Fung et al. (2005, 093262) did not report evidence of an association between respiratory
admissions and 24-h PMi0 concentration among adults <65 yr, in a study in Ontario, Canada, while
Ulirsch et al. (2007, 091332) reported a significant positive association among all ages and adults
(18-64 yr) in two Southeast Idaho cities for hospitalizations, ED and urgent care visits combined.
This estimate was robust to adjustment for gaseous pollutants.


      Older Adults

      Among older adults, MCAPS investigators observed largely null findings for PM25 and
respiratory hospitalizations (ICD-9: 490-492, 464-466, 480-487) for the U.S. as a whole, but
reported heterogeneity in effect estimates across the country that were explained by regional and
seasonal factors (Bell  et al., 2008, 156266). The nationwide excess risk of respiratory admissions
with PM2.5 was 0.22% (95% PI: -0.12 to 0.56, lag 0) (Bell  et al., 2008, 156266). The largest increase
was observed during the winter in the Northeast (1.76% [95% PI: 0.60-2.93], lag 0). Significant
increases in  respiratory admissions were also observed at lag 2. In an analysis of PMi0_2.5, MCAPS
December 2009                                 6-135

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investigators observed small imprecise increases in respiratory admissions with 24-h PM10 25
concentration (0.33% [95% PI: -0.21 to 0.86, per 10 ug/m3, lag 0]) (Peng et al, 2008, 156850).
which decreased after adjustment for PM25 (0.26% [95% PI: -0.32 to 0.84 per 10 ug/mj lag 0]).
Associations with PM2.5 increased (0.7% [95% PI: 0-1.5, lag 0]) or persisted (0.6% [95% PI: -0.2 to
1.25, lag 2]), after adjustment for PMi0_2.5.
     Two recent MCAPS analyses evaluate the effect of PM25 components on respiratory hospital
admissions. Bell et al. (2009, 191997) analyzed a subset of MCAPS  data restricted to 106 counties
with data available for both long-term average concentrations of PM25 components (Bell et al.,
2007, 155683) and PM25 total mass (1999-2005). The components evaluated included 20 chemicals
with demonstrated toxicity or that contribute a large proportion of PM25 mass (Al, NH4+, As, Ca, Cl,
Cu, EC, OCM, Fe, Pb, Mg, Ni, NO3", K, Si, Na+, Ti, V, Zn). Increases in effect estimates of 511%
(95% PI: 80.7-941) for EC, 223% (95% PI: 36.9-410) for Ni and 392% (95% CI: 46.3-738) for V per
IQR increases in county-specific component fraction were observed. Associations were somewhat
reduced and non-significant in two-pollutant models. When Queens or New York County were
excluded, the association of V with hospital admissions lost significance. Associations were also
diminished when alternative lag structures were considered.
     Peng et al. (2009, 191998) linked data on hospital admissions for respiratory causes among
older adults from 2000-2006 to daily air levels from the  STN in 119  counties in which both sets of
data were available. Chemical constituents  evaluated were SO42~, nitrate, Si, EC, OCM, sodium and
ammonium ions. Single-day lags of 0-2 days were considered. These investigators found a 0.82%
increase (95% PI: 0.22-1.44) per IQR increase in same day OCM. After adjustment for the other
components, a 1.01% (95% PI: 0.04-1.98, lag 0) increase in respiratory admissions per IQR increase
OCM was observed.
     French PSAS investigators reported a non-significant increase in hospitalizations for
respiratory diseases (ICD-10 JOO-J99) with 24-h avg PMi0_2.5 among older adults. PM25 estimates
were also not significant (Host et al., 2008, 155852). Adjusted estimates from two-pollutant models
were not presented. Positive associations of first hospitalization, overall hospitalizations and
readmission for respiratory diseases and PMi0_2 5 were also reported among older adults in Vancouver
(Chen  et al., 2005, 087555). PMi0.2.5 was associated with an increase of 15% (95% CI: 4.8-22.8) in
overall admissions per 10 ug/m3. Increases  associated with PMi0_2.s were larger for readmissions
compared to overall admissions. The association for PM25 with overall admissions was 5.1% (95%
CI: -4.9 to 13) and the association with readmissions was not larger.  In this study, effect estimates for
PMio_2.5 and PMi0lost precision, but were robust to adjustment for gaseous pollutants, while the
estimate for PM2 5 was null after adjustment for gaseous pollutants. In Vancouver, Fung et al. (2006,
089789) report increased admissions of 1.8% (95% CI: -2.5 to 5.8) per 10 ug/m  increase in PM2
                                                                                       2.5
and 3.8% (95% CI: 0-7.6) per 10 ug/m  increase in PMi0_2.5 (lag 0-1 day avg) among adults >65 yr.
      In a multicity Australian study, Simpson et al. (2005, 087438) examined the association
between PM25 measured by nephelometry and respiratory hospital admissions (ICD-9 460-519)
among older adults (>65 yr) and reported significant associations (1.055 [95% CI: 1.008-1.1045], lag
0-1 day avg) from a meta-analysis combining effect estimates from all cities. Results from three
statistical models were considered, including standard GAM, which produced similar results.
      Delfino et al. (2009, 191994) reported that PM2 5 from wildfire in California was associated
with respiratory hospital admissions among older adults (3% 95% CI: 1.1-4.9 per 10 ug/m3). In two
analyses of data collected in Copenhagen, Denmark between 1999 and 2004, several size fractions
including UF and accumulation mode (Andersen et al., 2008, 189651) and PMi0 sources (Andersen
et al., 2007, 093201) were investigated in relation to respiratory hospitalizations (J41-42, J43,
J44-46) among adults >65 yr of age. Of the size fractions examined (NC total, NC median diameter
of 12 nm [NCai2], NCa23, NCa57, NCai00, NCa2i2, PMi0, PM2.5) NCa2i2, typically aged secondary
long-range transported, NCa57 and PM10 were significantly associated with respiratory
hospitalizations (Andersen et al., 2008, 189651). PMi0 sources including biomass combustion,
secondary inorganic compounds, oil combustion, and crustal were associated with respiratory
hospitalizations (excess risks ranged from 3.5% to 5.4% per interquartile range, respectively)
(Andersen et al., 2007, 093201). PMi0 associations were diminished somewhat in two-pollutant
models (Andersen  et al., 2007, 093201: 2008, 189651): the authors note that it was difficult to
separate the effects of PM10 and NCa2i2, which were highly correlated in these data.  PM2 5 was not
associated with respiratory hospitalizations in these data.
      Results from other single-city studies offer somewhat consistent evidence for the effect of
     on respiratory admissions among older age groups. Ulirsch et al. (2007, 091332) found
December 2009                                 6-136

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increases in hospitalizations, ED and urgent care visits combined among this age group in two cities
of Southeast Idaho. Two studies in Vancouver report increased admissions for respiratory causes
with the largest effects observed for a 3-day ma (0-2 days) (Chen et al., 2005, 087555; Fung et al.,
2006, 089789). Fung et al. (2005, 093262) observed non-significant increases in admissions with
PMio among older adults in Ontario, Canada, while another study conducted in Ontario (Luginaah et
al., 2005, 057327) did not provide compelling evidence for an effect that was robust to method
selection, although some increases among males were observed. Finally, a study of hospital
admissions for cardiopulmonary conditions combined among older adults (>65 yr) in Allegheny
County, PA found a positive association with PMi0 at lag 0 (Arena et al., 2006,  088631).
      Effect estimates for adults (and combined age groups) as well as older adults are found in
Figure 6-11. Effects observed in single-city studies are generally imprecise but most studies report
positive associations. Regional and seasonal variation was observed with the largest effect estimate
reported by Bell et al. (2008, 156266) in the Northeast during the winter. Although the number of
studies examining components or sources was limited, EC, OC, Ni, V, and PM2.5 from mobile
sources were associated with increased respiratory admissions.  Several additional studies conducted
outside the U.S. and Canada reported  positive associations of respiratory hospitalizations with PMi0
for different age groups and lags (Bedeschi et al., 2007, 090712: Chen  et al., 2005, 087555: Chen
et al., 2006, 087947: Hanigan et al., 2008,  156518: Lai and Cheng, 2008, 180301: Larrieu  et al.,
2009, 180294; Middleton et al., 2008, 156760; Oftedal et al., 2003, 055623), PM25 (Hinwood et
al., 2006, 088976; Neuberger et al., 2004, 093249; Vigotti et al., 2007, 090711). BS (Bartzokas et
al., 2004, 093252; Tecer et al., 2008,  180030) and with PM10.2.5 (Tecer  et al., 2008, 180030). Other
studies reported no associations with PMi0 (Vegni and Ros, 2004, 087448) or TSP (Llorca et al.,
2005, 087825).


6.3.8.2.   Asthma

      Results from multicity studies of hospital admissions and ED visits for asthma as well as
single-city  studies conducted in the U.S. and Canada are summarized in Figure 6-12. Studies
reviewed in the 2004 AQCD are included for continuity. Concentrations of PM for the relevant study
period are found in Table 6-14.


      Children

      SOPHIA investigators (Peel et al., 2005, 056305) reported that, of the PM mass indicators
examined, the  largest effect estimate observed using the a priori lag (0- to 2-day avg) was the
association of  PMi0 with pediatric (2-18 yr) asthma ED visits (1.6% [95% CI: -0.2 to 3.4]). ED visits
for both asthma (ICD-9: 493) and wheezing (ICD-9: 786.09) were included in their study. New York
State DOH (2006, 090132)  conducted a study comparing effect estimates for ED visits for asthma
and 24-h PM25 and 1-h PM25 across two communities in New York City (the Bronx and Manhattan).
No associations with 24-h PM25 were reported for either borough for age categories 0-4 or 5-18 yr.
Non-significant increases with 1-h maximum PM2 5 were reported for the Bronx. Asthma hospital
admissions (ICD-10 J45, J46, J44.8) in children <14 yr were examined in the Australia/New Zealand
multicity study (Barnett et al., 2005, 087394). In this study, associations for asthma hospital
admissions with PM2 5 and PMio were increased but imprecise.
      Lin et al. (2002, 026067) used both time series and case-crossover approaches to investigate
the influence of PM on  asthma hospitalization in children,  6-12 yr old, in Toronto from 1981 to
1993. These authors report relatively small  differences in results obtained through bi-directional case
crossover and time series approaches, but indicate that unidirectional case-crossover methods may
overestimate the relative risks.  Single- to 7-day avg lags were investigated and estimates appeared to
increase and then  level off at the longer lags (0- to 2-day and 0- to 5-day lags are shown in Figure
6-12). Effect estimates for PM2 5 are not easily distinguished from the null, but PMi0_2.5 is
significantly associated with asthma admissions among boys and among girls. These associations
were imprecise, but robust to adjustment for gaseous  pollutants, among all children combined.
December 2009                                 6-137

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Study

Location Lag Age Gender
Effect Estimate (95% Cl)
ADULTS OR ALL AGES COMBINED
Peel etal. (2005.056305)*
Tolbertetal. (2007,090316)*
Slaughter et al. (2005, 073854)*
Host etal. (2008, 155852)
Delfino etal. (2009. 191994)
Peel etal. (2005.056305)*
Tolbertetal. (2007, 09031 6)*
Slaughter et al. (2005, 073854)*
Host etal. (2008, 155852)
Peel etal. (2005.056305)*
Tolbertetal. (2007, 09031 6)*
Luginaah et al. (2005, 057327)
Slaughter et al. (2005, 073854)*
Ulirsch etal. (2007. 091 332)**
Fung etal. (2005.093262)
Atlanta GA 0-2 All
Atlanta, GA 0-2 All -i
Spokane WA 1 All 	
6 Cities, France 0-1 15-64 — J
California Wildfires 0-1 20-64
Atlanta GA 0 ° All
Atlanta GA 0-° All 	 * 	
Spokane, WA 1 All — i
6 Cities France 0-1 15-64 — i
Atlanta, GA 0-2 All
Atlanta, GA 0-2 All
Windsor Can 1 All Female 	 i
? All Female ,......J
3 All Female
1 All Male
0 All MalP
3 All Male
Spokane, WA 1 All _i
2 All _j
3 All _i
Idaho 0 All
0 18-64
Ontarin,r.an n 
-------
       Although Ostro et al. (2009, 191971) presented estimates for all respiratory diseases
combined, these authors note that PM2.5 and its components were associated with asthma
hospitalizations among the children in six counties of Los Angeles studied. Delfino et al. (2009,
191994) examined the association of PM25 before, during, and after wildfires in California with
asthma hospitalizations among age and gender subgroups. Associations were observed for children
0-4 yr among children during the wildfire period (8.3% [95% CI: 2.1-14.9] per 10 ug/m3), but not
before or after the wildfire period. For older children, 5-19 yr, non-significant increases  in asthma
hospitalizations were found before the wildfire period,  but not during or after the fires.
      Hirshon et al. (2008, 180375) studied hospital admissions and ED visits by children 0-17 yr
old in Baltimore, MD from June 2002-November 2002, in relation to Zn as a component in PM2.5.
Single day lags from 0-2 days were tested with the highest estimates observed for the previous day.
A 23% (95% CI: 7-41) increase in admissions was observed comparing medium (8.63-20.76 ng/m3)
concentrations on the previous day to low concentrations (<8.63 ng/m ) on the previous  day.
Previous day high concentration (>20.76 ng/m3) was associated with an increase in admissions of
16% (95% CI: -3 to 39) compared to previous day low  concentration. Zinc associations  were robust
to adjustment for EC, CO, NO2, Ni, and Cr. However, evidence of effect modification by EC and
NO2 at lags 1 and 2 was observed.
      Mohr et al. (2008, 180215) used measurements of EC, O3, SO2, and total NOX from the EPA
supersite in St. Louis for June 2001-May 2003, to examine the association of EC, temperature and
season with asthma ED visits among children 2-17 yr old. The association of EC with asthma ED
visits varied by age, season and weekday versus weekend. The largest associations were observed for
2-5 yr olds during the fall weekends (3% [95% CI: 1-5] per 0.1 ug/m3) and 11-17 yr olds during
winter weekdays (3% [95% CI: 0-5] per 0.1 ug/m3) and summer weekends (9% [95% CI: 2-17] per
0.1  ug/m3). Investigators also report that temperature modified the effect of EC after adjusting for
gaseous copollutants, such that the association of ED visits with EC increased  with increasing
temperature during the summer and increased with decreasing temperature during the winter.
Authors attribute the temperature modification to time-activity patterns among this age group.
      Sinclair and Tolsma (2004, 088696) investigated respiratory ambulatory care visits using
ARIES data in Atlanta, GA (also used by SOPHIA investigators) and health insurance records. These
authors evaluated three 3-day ma lags (0-2, 2-5 and 6-8 days) and reported relative risks, with no
confidence intervals, for significant results only (not included in Figure 6-12).  For childhood asthma
outpatient visits, OHC, PMi0_2.5, PMi0, EC and OC were significantly associated with ambulatory
care visits at lags 0-2 or 2-5 days.
      A study in Anchorage used medical records to examine effects of particle exposure on
pediatric asthma outpatient visits, inpatient visits and prescriptions for short-acting inhalers
(Chimonas  and Gessner, 2007, 093261). Authors examined Medicaid claims for asthma-related and
lower respiratory infection visits among children less than 20 yr of age for 5 yr (approximately
25,000 children were enrolled in Medicaid each year between 1999 and 2003). Citing work done in
the  mid-1980's, the authors describe their city's particles as arising primarily from natural, geologic
sources (PMi0), and to a lesser extent from local automotive emissions (PM2 5) (Pritchett and
Cooper, 1985, 156886). Using GEE in a time-series analysis of daily and weekly effects of particle
exposure on health outcomes, the authors  found that each 10 ug/m3 increase in 24-h avg PMi0 was
associated with a 0.6% increase (95% CI:  0.1-1.3) in outpatient visits for asthma. The same increase
in weekly PMi0 concentration resulted in a 2.1% increase (95% CI: 0.4-3.8) in asthma visits, after
adjustment for gaseous pollutants. No meaningful associations were observed for PM25.
      In Copenhagen, Denmark, Anderson et al. (2007, 093201) found an association between PMi0
attributed to vehicle emissions  and asthma hospitalizations among children 5-18 yr (5.4% 95% CI:
0.57-22.9 per 10 ug/m3, 0- to 5-day avg). In an analysis of size distribution and number
concentration, accumulation mode particles were most  strongly associated with asthma admissions
(8% [95% CI: 0-17] per 495  particles/cm3, lag 0-5). (Andersen et al., 2008, 189651). In Helsinki,
Halonen et al. (2008, 189507) examined the association of various size fractions of PM  (e.g., Aitken,
accumulation mode, PM2 5, PMi0_2.5) with  ED visits for asthma among children <15 yr. These  authors
evaluated lags 0-5 and noted a different lag structure depending on age with children experiencing
greater effects at lags 3-5 days  compared to adults  at lag 0. Aitken, accumulation mode particles and
traffic-related PM were significantly and most strongly associated with asthma visits among
children, while no association with PMi0_2.5 was observed in this age group.
December 2009                                 6-139

-------
Sti












c
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15
.0
o
and All Ages C
M
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idy
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nplfinnptal f9nDQ 1Q1QQ41


093261)
NYS DOH (2006 090132) *



Linetal (2002 026067)



Barnettetal (2006 089770)

Peel etal. (2005, 056305)*
Linetal (2002 026067)



Chirnonas & Gessner (2007
093261)
Peel etal. (2005, 056305)*
Ito etal. (2007.091262)*
^lannhtprptal (TTfK flTWiai*


nplfinnptal f9nDQ 1Q1QQ41

Sheppard et al. (2003, 042826)
MY^ now f9nnfi noniTO*

pppiptai nnnR rww^*
Slaughter et al. (2005, 073854)*
Sheppard et al. (2003, 042826)
NYS DOH (2006 090132)*

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Jaffe etal. (2003. 041 957)*

Slaughter et al. (2005, 073854)*
Sheppard etal. (2003. 042826)
Location










Bronx NY

Manhattan NY





Australia/NZ

Atlanta, GA





Atlanta, GA
New York, NY




(wildfire)
Seattle, WA
RrnnY MY
Manhattan MY
Atlanta I^A
Spokane, WA
Seattle, WA
Bronx NY
Manhattan NY
Atlanta, GA
3 Cities, OH

Spokane, WA
Seattle, WA
Lag
n 1
0-1
0-2
n ^
n 9
0-5
n 1
0-1
o
o
0-4
0-4
0-4
0-4
0-2
0-5
0-2
n ^
0-1
0-1
0-2
0-2
0-5
0-2
0-5
o
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0-2
0-1
0-1
0-1
1
2
•t
n 1
0-1
0
n 4
n 4
n 9
1
2
3
0
0-4
0-4
0-2
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3
3
2
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1
2
3
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Covariates, Age
1 A
5 14
Boy 6 1°

Pirl- R 1°
Girl" 61°
n.4
5 19 i

Outpatient 019 •
0 1
518 *
Q /\ <; t
5 18 <«
Boys 6-12 —I
Boys 6-12
Girls 6-12 	
Rirk fi 19
1-4 -J
5-1/1 	
2-18 J
Boys 61°
Boys 61° 	
Girls 612 	
Girls 6-1°
Inpatient 019
Outpatient, 0-19
All Ages 	 1
All Year, All
Cool Season, All
nil 	
All
All
9n ftd J
65+
<65
All
All
All •
All J
All — I
All 	 «i
<65 —I
All
All
All J
All
All cities, 5-34 — i
Columbus, 5-34
Columbus 5-34 	 '
All J
All — I
All 	 i
<65
Effect Estimate (95% Cl)
• PMl r

||


—




L,



f PMl'-r
9 v.


* PMm

L_» 	




L*.
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—
^ 	


^
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L_. 	
l» 	
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  * ED Visits
 DL Distributed Lag


Figure 6-12.
                                    i   I  I   i  i   i  I   i   i  i   I  i   i  i   I  i   i
                                    -8-40    4     8    12    16    20   24
                                         Excess Risk (%)
Excess risk estimates per 10 ug/m increase in 24-h avg PM2.6, PMi0.2.5, and
for asthma ED visits and HAs. Studies represented in the figure include all
multicity studies as well as single-city studies conducted in the U.S. or Canada
     Adults and All Ages Combined

     Results from the Atlanta SOPHIA study based on the a priori models examining a 3-day ma
(lag 0-2 days) revealed no statistically significant associations with asthma (ICD-9 493, 786.09)
December 2009
                             6-140

-------
among all ages for any of the PM metrics studied (e.g., PM2.5, PM10_2.5, PM10, UF PNC, PM
components) (Peel et al., 2005, 056305). However, the 14-day unconstrained distributed lag model
produced an excess risk of 9.9% (95% CI: 6.5-13.5 per 10 ug/m3 PMi0). The authors note that
associations of PM25 and OC with asthma tended to be stronger during the warmer months. Sinclair
and Tolsma (2004, 088696) report a significant association between adult outpatient visits for asthma
and UFPs, but not other PM size fractions (not included in Figure 6-12 because only significant
results were presented).
      Jaffe et al. (2003, 041957) examined the effects of ambient pollutants (PMi0, O3, NO2 and
SO2) during the summer months (June through August) on the daily number of ED visits for asthma
among Medicaid recipients aged 5-34 yr from 1991 to 1996 in Cincinnati, Columbus, and Cleveland.
Lags 1 to 3 were tested and only statistically significant lags were presented. For all cities combined,
the overall effect estimate for 24-h avg PM10 was 1.0% (95% CI: -1.44 to 3.54 per 10 ug/m3
increase). The effect estimate for Cleveland was the only significantly elevated estimate (2.3%
[95% CI: 0.0-4.9] per 10 ug/m3 increase) when the cities were examined independently. The authors
reported results from analyses indicating a possible concentration response for O3, but no consistent
effects for PMi0.
      In New York City, Ito et al. (2007, 156594) examined numbers of ED visits for asthma among
all ages (ICD-9 493) in relation to pollution levels from 1999 to 2002; several weather models were
evaluated. Although the association with NO2 was the strongest, PM2 5 was significantly associated
with asthma ED visits in each weather model (strongest during the warm months) and remained
significant after adjustment for O3, NO2, CO and SO2. Slaughter et al. (2005, 073854) reported  no
associations with ED visits or hospitalizations for asthma, among all ages, in Spokane, Washington
for the PM size fractions studied (PMb PM2 5, PMi0, PMi0_2.5). An association with CO, which the
authors attribute to combustion related pollution  in general,  was observed. The effect of 24-h avg
and 1-h max PM25, PM10_2.5, EC and OC on ED visits for asthma among all ages combined,
comparing two communities in New York City was investigated (ATSDR, 2006, 090132). In the
Bronx, an increase in visits of 3.1% (95% CI: 0.6-6.2 per  10 (ig/m3) was observed in relation to 24-h
avg PM25. For PMi0_2.5, an increase of 2.7% (95% CI:  0.0-5.4) was observed in the Bronx.  Smaller,
less precise estimates were observed for Manhattan. Increased asthma visits were observed with OC,
EC and total metals. In the Bronx, the association of 1-h max PM25 with ED visits was larger than
the association with 24-h PM2 5 when standardized to the mean concentration for both communities
and was generally robust to adjustment for copollutants.
      Delfmo et al. (2009,  191994) examined the association of PM25 before, during and after
wildfires in California with asthma hospitalizations among age and gender subgroups. The increase
among older adults >65 yr of 10% (95% CI:  3-17.8 per 10 (ig/m3) was larger than the increase
among adults 20-64 yr of 4.1% (95% CI: -0.5 to 9 per 10 (ig/m3). For older adults, the association
was stronger during the wildfire period compared to the pre-wildfire period and did not diminish
during the post-wildfire period.
      Effect estimates from studies of hospital admissions and ED visits for asthma are summarized
in Figure 6-12. Associations with PM25  concentration among children are imprecise and not
consistently positive across different age groups and lags. Findings from two studies of PMi0_2.s
(Sinclair and Tolsma, 2004, 088696). as well as PMi0 studies both show positive associations,
although estimates lack precision. Among adults  and adults  and children combined, associations of
asthma hospital admissions and ED visits with PM25 concentration were observed in most studies.
Positive, non-significant associations of PMio_25 concentration with asthma admissions and ED visits
were observed in some studies of adults. Again, PMi0 estimates are more consistently positive and
precise compared to other size fractions. Associations were observed with several PM2 5 components
(e.g., EC, OC and Zn) and  sources (e.g., traffic, wildfires). Many factors (e.g., the underlying
distribution of individual sensitivity and severity, medication use and other personal behaviors) can
influence the lag time observed in observational studies (Forastiere  et al.,  2008, 186937). Excess
risk estimates for asthma were generally sensitive to choice  of lag and increase with longer or
cumulative lags times. Most additional single-city studies conducted in Europe, South America and
Asia, have investigated the associations of asthma hospitalizations, ED visits or doctor visits and
most have reported evidence of an association with TSP (Arbex  et al., 2007, 091637; Migliaretti
and Cavallo, 2004, 087425; 2005, 088689). PM10 (Bell et al., 2008, 156266; Bell et al., 2008,
091268; Chardon et al.,  2007, 091308; Chen et al., 2006, 087947; Erbas  et al., 2005, 073849;
Galan  et al., 2003, 087408; Jalaludin et al., 2004,  056595; Kim et al., 2007, 092837; Ko  et al.,
2007. 091639; Kuo  et al.. 2002. 036310; Lee et al.. 2002. 034826; Lee et al., 2006, 090176) and
December 2009                                 6-141

-------
PM2.5 (Chardon et al., 2007, 091308; Ko et al, 2007, 091639)) (Ko  et al., 2007, 196606) while a
few have not shown an association with PMi0 (Larrieu et al., 2009, 180294; Masjedi  et al., 2003,
052100; Tsai et al., 2006, 089768; Yang and Chen, 2007, 092847; Yang et al., 2007, 092848).
6.3.8.3.   Chronic Obstructive Pulmonary Disease

      Results from multicity studies of hospital admissions and ED visits for COPD as well as
single-city studies conducted in the  U.S. and Canada are summarized in Figure 6-13. Studies
reviewed in the AQCD are included in the figure for continuity. Concentrations of PM for the
relevant study period are found in Table 6-14.
      In a study of Medicare recipients in 204 U.S. counties, Dominici et al. (2006, 088398)
reported an overall increase of about 1% in COPD hospitalizations (ICD-9 490-492) associated with
24-h avg PM2.5, with the largest effects at lags 0 and 1. In this study effect estimates were
heterogeneous across the U.S.  with  a significant increase of about 4% observed in the Southeast at
lag 0. In another study using Medicare data in 36 U.S. cities (1986-1999) short-term exposure to
PMio was associated with an increase in COPD hospital admissions (ICD-9 490-496, excluding 493)
of 1.47% (95% CI: 0.93-2.01,  lag 1) during the warm season (Medina-Ramon et al., 2006, 087721).
A smaller effect was observed during the cold season.
      In Atlanta, SOPHIA investigators  reported a comparably sized effect estimate for COPD
(ICD-9 491, 492, 496) and 24-h avg PM25 (1.5% [95% CI: -3.1 to 6.3], 0- to 2-day avg]). The
association of PMi0 with COPD reported by Peel et al. (2005, 056305) was 1.8% (95% CI: -0.6 to
4.3). No associations were observed for  PMi0_2.5, UF or PM2.5 components. Slaughter et al. (2005,
073854) reported no associations between any size fraction of PM in  Spokane, Washington (PM25,
PM10_25, PM10) and COPD (ICD-9 491, 492,  494, 496). In contrast, Chen et al. (2004, 087262)
reported increases in COPD admissions  (ICD-9 490-492, 494, 496) for PM25 (17.1% [95% CI:
4.6-31.0], 0- to 2-day avg), PM10_25  (10.0% [95% CI: -1.2  to 22.8, 0- to 2-day  avg]), and PM10
(16.5% [95% CI: 6.88-27.02],  0- to  2-day avg]). However, the estimates  for PM metrics were
diminished after adjustment for NO2.
      Delfmo et al. (2009, 191994)  examined the association of PM25 from the wildfires  of 2003 in
California with COPD hospitalizations among age and gender subgroups. Among older adults (>65
years), associations were similar across pre-, post- and wildfire periods with none reaching
significance. The increase for all periods combined in this age group was 1.9% (95% CI:  -0.6 to 4.4,
per 10 (ig/m3). Michaud et al. (2004, 188530) reported an  association for asthma and COPD ED
visits combined with PMi (lag 1) in Hilo, Hawaii in a study designed to investigate the effect of
volcanic fog.
      Halonen et al. (2008, 189507) conducted a study of ED visits for COPD and asthma combined
(J41, J44-J46) among adults 15-64 yr and older adults >65 yr. These authors examined  the effects of
Aitken mode particles, accumulation mode particles, PM2  5 and PMi0_2.5 as well as several sources of
PM2 5 (traffic, long range transported particles, road dust and coal/oil  combustion). Concentrations,
lagged from 0-5 days, were examined and the largest effects among older adults were observed in
association with concurrent day PM2 5, PM10_2.5, accumulation mode particles,  NO2, and CO
concentrations. The PM25 association was diminished with adjustment for UFPs, NO2and CO. A
similar diminishment was observed  when PMi0_2.5 was adjusted for PM2 5, NO2 and CO. However,
traffic related particles and long range transported particles (e.g., accumulation mode particles such
as carbon compounds, sulfates and nitrates from central Europe and Russia) were associated with
COPD and asthma among older adults. This same research group conducted additional analyses of
hospital admissions using the same  PM metrics focusing on older adults  (>65 yr) (Halonen  et al.,
2009, 180379). The PM2 5 results and lag structure were similar to the earlier ED visit study. The
strongest effect was for accumulation mode particles with  COPD/asthma admissions. Traffic related
PM2 5 was associated with COPD/asthma admissions at lag 1 while no effect was observed with
concurrent day concentration. Long range transported particles and road  dust were also associated
with admissions for asthma and COPD.
      With the exception of one study conducted in Spokane Washington (Slaughter et al., 2005,
073854). associations have been consistently observed for PM2 5 and PMio with COPD in multicity
and single-city studies conducted in the  U.S.  and Canada.  Associations with PMi0_2.5 are fewer and
less consistent. A study that examined seven  single-day lags in association with pooled COPD and
asthma ED visits in Finland reported that PM2 5, PMi0_2.5, traffic sources as well as gaseous pollutants
December 2009                                 6-142

-------
had a more immediate effect in older adults (lags 0 and 1) compared to children experiencing asthma
(3- to 5-day lags) (Halonen  et al., 2008, 189507). Larger estimates at shorter lags were not observed
consistently across other studies. Most single-city studies conducted outside of the U.S. or Canada
focused on PMi0 (Chiu et al., 2008, 191989: Hapcioglu et al., 2006, 093263: Ko et al., 2007,
091639: Ko et al.. 2007. 092844: Martins et al.. 2002. 035059: Masjedi  et al.. 2003. 052100:
Sauerzapf et al., 2009, 180082: Yang and Chen, 2007, 092847).
Study
Location
Lag     Age/Climate
Effect Estimate (95% Cl)
Dominici et al. (2006, 088398)



Chen (2004 087262)



Delfinoetal. (2009, 191994)
Ito (2003 042856)
Moolgavkar (2003, 051316)
Slaughter et al (2005 073854)*


Chen (2004 087262)



Ito (2003 042856)
Zanobetti & Schwartz (2003, 043119)
Medina-Ramon (2006, 087721)
Peel (2005. 056305)*
Slaughter et al (2005 073854)*

Chen (2004 087262)



Ito (2003 042856)
Moolgavkar (2003, 051316)
* ED Visits
204 Counties, US







6 Counties, CA
Detroit Ml
Los Angeles, CA
Atlanta ft A



Vancouver Can



Detroit Ml
14 Cities, US
36 Cities, US
Atlanta, GA
Spokane WA





Detroit Ml
Los Angeles, CA
Cook County, I L

0 '-*•
1 '-•-
2 -"•—
0-2 DL «-•-
1 * '

3 *
1 65+ '
0 i


0-1 avg 65* -J — » 	
0 6S4- b
0 65+ «-«_
1 '•
i 	 « 	 i 	
3 ' •
1 1
0 1 ,
T. 1
^ =wn i
0 ' »
0-1 avg i -*-
0 Warm U-
1 Warm i _»..
0 Cold -*-
1 Cold Jo.
0 1 3 DL '
1 k
2 .------^----^
1
?
^
0-2 avg
0 •
o u-
0 L«,
1
1 1 1 1 1 1 1 1 I
-12 -8-40 4
Excess Risk (%)
A
PM2.5





—



10-2.5





^

PMio



*




i 1 I 1 I 1 I I 1
8 12 16 20 24
              for COPD ED visits and HAs among older adults (65+ yr, unless other age group
              is noted). Studies represented in the figure include all multicity studies as well as
              single-city studies conducted in the U.S. or Canada.
6.3.8.4.   Pneumonia and Respiratory Infections

      Results from multicity studies of hospital admissions and ED visits for respiratory infection as
well as single-city studies conducted in the U.S. and Canada are summarized in Figure 6-14. The
figure includes studies of respiratory infection reviewed in the 2004 AQCD. Concentrations of PM
for the relevant study period are found in Table 6-14.
December 2009
                     6-143

-------
      Children

      In the study of seven cities in Australia and New Zealand, associations of PM25 with
pneumonia and acute bronchitis (ICD-10 J12-J17, J18.0, J18.1, J18.8, J18.9, J20, J21) were observed
among infants <1 yr old (4.54% [95% CI: 0.00-9.20]) and children 1-4 yr old (6.44% [95% CI:
0.26-12.85]) (Barnett  et al, 2005, 087394). Although quantitative results were only presented for all
respiratory diseases combined, Ostro et al. (2009, 191971) examined several specific respiratory
diseases including acute bronchitis and pneumonia. They reported that PM2.5 and its components
were more strongly associated with these endpoints compared to other respiratory diseases. Delfino
et al. (2009, 191994) reports imprecise increases in admissions among children during wildfire
periods for acute bronchitis and bronchiolitis, as well as pneumonia.
      Inpatient and outpatient visits for lower respiratory tract infections among children in
Anchorage, Alaska, were not associated with PM25 or PMi0 (Chimonas and Gessner, 2007, 093261).
Lin et al. (2005, 087828) observed associations of respiratory infections (ICD-9 464, 466, 480-487)
with PM 10-2.5 and PMi0 that persisted after adjustment for gaseous pollutants among subjects <15  yr
old living in Toronto. Analyses were stratified by gender and both single and multiple day lags were
examined (4- and 6-day avg were presented). The largest significant effect estimates were for
PMio_2.5. The size of the PM2.5 estimate varied by gender and was sensitive to the choice of lag. PM2.5
results were not generally robust to adjustment for gases.


      All Ages and Older Adults

      SOPHIA investigators examined ED visits for upper respiratory tract infections (URI) (ICD-9
460-466, 477) and pneumonia (ICD-9 480-486) among all ages. An excess risk of 1.4% (95% CI:
0.4-2.5 per 10 ug/m3, lag 0- to 2-day avg) for PMi0 was associated with URI visits. With the
exception of a small increase in risk for OC of 2.8% (95% CI: 0.4-5.3 per 2 ug/m3, 0- to 2-day avg)
with pneumonia visits, Peel et al. (2005, 056305) reported no association with other PM size
fractions or components evaluated. However, Sinclair and Tolsma (2004, 088696). who also used
ARIES data in their analysis, reported significant associations with outpatient visits for LRI. These
associations were generally observed for 3- to 5-day ma lags, in association with PMi0_2.5, PMi0, EC,
OC, and PM2 5 water soluble metals (not pictured in figure because only significant lags were
reported). No associations  with pneumonia for any size fractions were observed among all ages in a
study  conducted in Spokane, Washington (effect estimates were not reported) (Slaughter et al.,
2005, 073854).
      French PSAS investigators examined the effect of PM25 and PMi0_25 on hospital  admissions
for respiratory infection (ICD-10: J10-22) among all ages. Increases of 2.5% (95% CI:  0.1-4.8) and
4.4% (95%CI: 0.9-8.0) per 10 ug/m3 were observed in association with PM2.5 and PMi0_2.5,
respectively (Host  et al., 2008,  155852). In a multicity study of older adults (>65 yr) Medina-Ramon
et al. (2006, 087721) examined hospital admissions for pneumonia (ICD-9 480-487) in 36 U.S. cities
in relation to 24-h avg PM10 concentration. An increase in pneumonia admissions of 0.84% (95% CI:
0.50-1.19 per 10 ug/m3, lag 0) was reported by these investigators during the warm season.  Cold
season associations were weaker (0.30% [95% CI: 0.07-0.53] per 10 ug/m3, lag 0) as were lag 1
associations. Dominici et al. (2006, 088398) investigated hospital admissions for all respiratory
infections including pneumonia (ICD-9 464-466, 480-487) among older adults in 204 urban U.S.
counties in relation to  PM2 5 and reported a significant increased risk only at lag 2. Heterogeneity  in
effect estimates was observed across the U.S. with the largest associations reported for the South  and
Southeast.
      In Boston, excess risks of pneumonia hospitalization in association with PM25, BC, and CO
were observed among older adults (Zanobetti and Schwartz, 2006, 090195). A measure of
non-traffic PM, e.g., the residuals from the regression of PM25 on BC,  was not associated with
pneumonia hospitalization in these data. In a California study (Delfino et al., 2009, 190254). effect
estimates were of similar magnitude for pneumonia admissions associated with PM2 5 from wildfires
among all ages combined and older adults (2.8% [95% CI: 0.7-5.0] per 10 ug/m3, all ages
combined). The PM2 5 association with acute bronchitis and bronchiolitis admissions during the
wildfire period for all  age groups showed an approximately 10% increase (9.6%  95% CI: 1.8-17.9,
per 10 ug/m3). The increase was not larger during the wildfire period compared to the pre-fire period
for either outcome.
December 2009                                 6-144

-------
      In a study of four cities in Australia, statistically significant associations of pneumonia and
acute bronchitis with particles measured by nephelometry (but not PM2 5 mass) and NO2 were
observed among older adults (Simpson et al, 2005, 087438). Halonen et al. (2009, 180379)
examined pneumonia among older adults (ICD10 J12-J15) in their most recent analysis. Associations
of PM2.5 (5.0% [95% CI: 1.0-9.3] per 10 (ig/m3, lag 5-day mean), as well as accumulation mode
particles, with pneumonia admissions were observed.
      Although the body of literature is small, several studies of children reported associations  of
PM2.5, PMio_2.5 and PMi0 with respiratory infections but the outcomes studied are heterogeneous and
effect estimates are imprecise. Studies of adults  show a similar pattern of increased risk for each of
these size fractions. Several other single-city studies  conducted outside the U.S. and Canada reported
associations for PMi0 (Cheng  et al.. 2007. 093034; Hwang and Chan, 2002, 023222; Nascimento et
al., 2006, 093247) and PM2.5 (Hinwood  et al., 2006,  088976) with hospitalization or ED visits for
respiratory infections.
Study
                          Location
                                         Lag   Age Outcome
              Effect Estimate (95% CI)
CHILDREN
Barnettetal. (2006.089770)
                          7 Cities, Australia/NZ

Chimonas & Gessner (2007,093261) Anchorage, AK

Delfino et al. (2009,191994)       6 Counties, S. CA
Lin etal. (2005.087828)
Lin etal. (2005.087828)
Barnettetal. (2006.089770)
                          Ontario, Can
                          Ontario, Can
                          7 Cities, Australia/NZ
Chimonas & Gessner (2007,093261) Anchorage, AK

Lin etal. (2005.087828)          Ontario, Can
ALL AGES COMBINED OR OLDER ADULTS
Dominici et al. (2006,088398)      204 Counties, US
                                         0-1
                                         0-1
                                         0
                                         0
                                         0-1
                                         0-1
                                         0-1
                                         0-3
                                         0-3
                                         0-1
                                         0-1
                                         0
                                         0-1
                                         0-3
Dominici et al. (2006,088398)
Zanobetti & Schwartz (2006,09019

Peel etal. (2005,056305)*

Host etal. (2008.155852)
Delfino etal. (2009.191994)

Ito (2003.042856)
Peel etal. (2005.056305)*
                          90 Counties, US
                          Boston, MA

                          Atlanta, GA

                          6 Cities, France
                          6 Counties, S.CA

                          Detroit, Ml
                          Atlanta, GA
Host et al. (2008,155852)         6 Cities, France
Ito (2003,042856)              Detroit, Ml
Medina-Ramon et al. (2006,087721) 36 Cities, US
Peel etal. (2005.056305)*
Zanobetti (2003.043119)
Ito (2003.042856)
                          Atlanta, GA
                          14 Cities, US
                          Detroit, Ml
                                                1-4
                                                0-19
                                                0-19
                                                0-4
                                                0-4
                                                5-19
                                                1-4
                                                0-19
                                                0-19
Pneumonia
Pneumonia
LRI
LRI
0
1
2
0-2 DL
0
0-1
0-3
0-3
0-1
0-1
0-1
0
0-3
0-3
0-1
0
0
1
0
1
0-3
0-1 SDL
0-3
0-1 SDL
0-1
0
65+
65+
65+
65+
65+
65+
All
All
All
All
All
65+
All
All
All
65+
65+
65+
65+
65+
All
All
All
All
65+
65+
RTI
RTI
RTI
RTI
Pneumonia
Pneumonia
URI
Pneumonia
RTI
Pneumonia
Bronchiolitis
Pneumonia
Pneumonia
URI
RTI
Pneumonia
Pneumonia
Pneumonia
Pneumonia
Pneumonia
URI
URI
Pneumonia
Pneumonia
Pneumonia
Pneumonia
                                                    PM2.5
Bronchitis, Bronchiolitis
Pneumonia          —
Pneumonia
RTI
RTI
Pneumonia, Acute Bronchitis
Pneumonia, Acute Bronchitis
LRI
LRI
RTI
                      i Outpatient
                      i— Inpatient
                                    -Wildfire
                                                                                -Wildfire
                                                                                	Wildfire
                       - Outpatient
                       •—Inpatient
                                                   PM1025
                                                    PM10
                                                                                                        PM2.
                                                                             -Wildfire
                                                                                       -Wildfire
                                                                         '•Warm
                                                                         i*Warm
                                                                         i»Cold
                                                                                                      PM1(>
                                                                                                        PM,<
*ED Visits
DL = Distributed Lag


 Figure 6-14.
                                                               -10
                                                                                        20      30
                                                                   Excess Risk (%)
                Excess risks estimates per 10 ug/m  increase in 24-h avg PM2.6, PMi0.2.5, and PMi0
                for respiratory infection ED visits* and HAs. Studies represented in the
                figure include all multicity studies as well as single-city studies conducted in the
                U.S.
December 2009
                                                  6-145

-------
Table 6-14. PM concentrations in epidemiologic studies of respiratory diseases.
Study
Location
Mean Concentration
(ug/m3)
Upper Percentile
concentrations (ug/m )
PMts
Andersen et al. (2007, 093201)
Barnett et al. (2005, 087394)
Bell et al. (2008, 156266)
Chardonetal. (2007, 091308)
Chen et al. (2004, 087262; 2005, 087555)
Chimonas and Gessner (2007, 093261)
Delfino et al. (2009, 191994)
Dominici et al. (2006, 088398)
Funq et al. (2006, 089789)
Halonen et al. (2008, 189507)
Host et al. (2008, 155852)
Itoetal. (2007, 091262)
Lin et al. (2002, 026067)
Lin et al. (2005, 087828)
Moolqavkar (2003, 051316)
New York State DOH (2006, 090132)
Peel et al. (2005, 056305)
Sinclair and Tolsma (2004, 088696)
Sheppard et al. (2003, 042826)
Slaughter etal. (2005, 073854)
Tolbertetal. (2007, 090316)
Yanq et al. (2004, 087488)
Zanobetti and Schwartz (2006, 090195)
Copenhagen, Denmark
7 Cities Australia, NZ
202 U.S. counties
Paris, France
Vancouver, Canada
Anchoraae, AK
6 counties, CA
204 U.S. counties
Vancouver, Canada
Helsinki, Finland
6 Cities France
New York, NY
Toronto Canada
Ontario, Canada
LosAnaeles, CA
Bronx/Manhattan
Atlanta, GA
Atlanta, GA
Seattle, WA
Spokane, WA
Atlanta, GA
Vancouver, Canada
112 U.S. cities
10
8.1-11
12.92
14.7
7.7
6.1
18.4-32.7
13.4
7.72
NR; Median = 9.5
13.8-18.8
All vr: 15.1
17.99
9.59
22 (median)
15.0/16.7
19.2
17.62
16.7
NR
17.1
7.7
11.1 (Median)
99th: 28
Max: 29.3-122.8
98th: 34. 16
75th: 18.2
Max: 32
Max: 69.8
45.3-76.1 (mean durina wildfire period)
75th: 15.2
Max: 32
Max: 69.5
95th: 25.0-33.0
All vr: 95th: 32
Max: 89.59
Max: 73
Max: 86
NR
90th: 32.3; 98th: 39.8
NR
98th: 46.6
Max: 20.2 (usina 90% of concentrations)
90th: 28.8; 98th: 38.7
Max: 32.0
95th: 26.31
PMw-u
Chen et al. (2004, 087262; 2005, 087555)
Funa et al. (2006, 089789)
Halonen et al. (2008, 189507)
Hostetal. (2008, 155852)
Lin et al. (2002, 026067)
Lin et al. (2005, 087828)
New York State DOH
Peel et al. (2005, 056305)
Pena et al. (2008, 156850)
Sinclair and Tolsma (2004, 088696)
Sheppard et al. (2003, 042826)
Slaughter etal. (2005, 073854)
Tolbertetal. (2007, 090316)
Yana et al. (2004, 087488)
Vancouver, Canada
Vancouver, Canada
Helsinki, Finland
6 Cities France
Toronto, Canada
Ontario, Canada
Bronx/Manhattan
Atlanta, GA
108 U.S. counties
Atlanta, GA
Seattle, WA
Spokane, WA
Atlanta, GA
Vancouver, Canada
5.6
5.6
NR; Median: 9.9
7.0-11.0
12.17
10.86
7.69/7.10
9.7
NR; Median: 9.8
9.67
16.2
NR
9
7.7
Max: 24.6
Max: 27.07
Max: 101.4
95th: 12.5-21.0
Max: 68.00
Max: 45
NR
90th: 16.2
75th: 15.0
NR
Max: 88
NR
90th: 15.1: Max: 50.3
Max: 24.6
PM10
Andersen et al. (2007, 093201)
Barnett et al. (2005, 087394)
Chardonetal. (2007, 091308)
Chen et al. (2004, 087262; 2005, 087555)
Chimonas and Gessner (2007, 093261)
Funa et al. (2005, 093262)
Funa et al. (2006, 089789)
Gordian and Choudhurv (2003, 054842)
Jaffeetal. (2003, 041957)
Copenhaaen, Denmark
7 Cities, Australia, NZ
Paris, France
Vancouver, Canada
Anchoraae, AK
Ontario, Canada
Vancouver, Canada
Anchoraae, AK
Cincinnati, OH
25/24
16.5-20.6
23
13.3
27.6
38
13.3
36.11
43
75th: 30 /99th: 72
Max: 50.2-156.3
Max: 97.3
Max: 52.2
Max: 421
Max: 248
Max: 52. 17
Max: 210.0
Max: 90
December 2009
6-146

-------
              Study
    Location
Mean Concentration
     (ug/m3)
  Upper Percentile
concentrations (ug/m
Jalaludin et al (2004 056595)
Lin et al. (2002, 026067)
Lin et al. (2005, 087828)
Luainaah et al. (2005, 057327)
Medina-Ramon et al. (2006, 087721)
Moolaavkar (2003, 051316)
Moolaavkar (2003, 051316)
Peel et al. (2005, 056305)
Sinclair and Tolsma (2004, 088696)
Slaughter etal. (2005, 073854)
Tolbertetal. (2007, 090316)
Ulirschetal. (2007, 091332)
Yana et al. (2004, 087488)
Zanobetti (2003, 043119);Sametetal. (2000, 010269)
Svdnev Australia
Toronto, Canada
Ontario, Canada
Ontario, Canada
36 U.S. Cities
LosAnaeles, CA
Cook Countv, IL
Atlanta, GA
Atlanta, GA
Spokane, WA
Atlanta, GA
Idaho
Vancouver, Canada
14 U.S. Cities
228
30.16
20.41
50.6
15.9-44.0
22 (median)
35 (median)
27.9
29.03
NR
26.6
23.2
13.3
24.4-45.3
May 44 9
Max: 116.20
Max: 73
Max: 349
NR
Max: 86
Max: 365
Max: 44.7
NR
Max: 41.9 (using 90% of concentrations)
90th: 42.8
Max: 183.0
Max: 52.2
Max 94.8-605.8
UFP
 Andersen et al. (2008,1896511
Copenhagen, Denmark  Mean particles/cm : 6847
                  99th: 19,895 particles/cm3
 Halonen et al. (2008,1895071
               NR: Median particles/cm3: 8,203 Max: 50,990 particles/cm3
6.3.8.5.   Copollutant Models

      Some studies have investigated potential confounding by copollutants through the application
of multipollutant models (Figure 6-15). Several Canadian studies of respiratory hospital admissions
reported larger effects for PMi0 2 5 compared to PM2 5 that were robust to adjustment for gaseous
pollutants (Chen et al., 2005, 087555; Lin  et al., 2002, 026067; Yang et al., 2004, 087488). The
COPD associations between PM2.5 and PMi0_2.5 reported by Chen et al. (2004, 087262) remained
positive but were diminished slightly after adjustment for NO2. The associations reported by Ito et al.
(2003, 042856) of PM25 and PMi0_2.5 with pneumonia hospital admissions remained after adjustment
for gases, while  the association of PM10_25 with COPD admissions was not robust to adjustment for
O3. Associations reported by Burnett et al. (1997, 084194). Moolgavkar et al. (2003, 042864) and
Delfino et al. (1998, 093624) were not consistently robust to adjustment for gaseous copollutants. In
the MCAPS study, the effect of PM2.5 was robust to adjustment for PMi0_2.5, while the PMi0_2.5 effect
on respiratory admissions was diminished after adjustment for PM25 (Peng  et al., 2008,  156850).
Effect estimates  for PMi0 were robust to adjustment for gases in several recent studies (Andersen et
al., 2007,  093201;  Tolbert et al., 2007, 090316; Ulirsch  et al., 2007, 091332).
      Multiple pollutant analyses for other size fractions and components have been conducted in a
some additional  studies. PMi0  associations with respiratory disease did not change in models also
containing total  PNC, nor did the association of ACP diminish after adjustment for UFP
concentration(Andersen  et al., 2008, 189651). Peng et al. (2009, 191998) reports an OCM effect that
was robust to adjustment for other  components while the associations with Ni, V, and EC were
somewhat diminished in models containing multiple components.
      Inconsistency across these study findings is likely due to differences in the correlation
structure among pollutants as well  as differing degrees of exposure measurement error.
December 2009
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Study
Peng etal. (2008, 1568501
Lin etal. (2005, 0878281
Chen etal. (2005, 0875551
Chen etal. (2004, 0872621
Ito (2003, 0428561
Moolgavkar (2003, 0428641
Sheppard (2003, 0428261
Lin etal. (2002. 0260671
Delfinoetal. (1998, 0936241
Burnett etal. (1997,0841941
Thurstonetal. (1994, 0439211
Peng etal. (2008, 1568501
Lin etal. (2005,0878281
Chen etal. (2005, 0875551
Chen etal. (2004, 0872621
Yang etal. (2004,0874881
Ito (2003, 0428561
Lin etal. (2002, 0260671
Burnett etal. (1997,0841941
Outcome
Respiratory Disease
Respiratory Infection
Respiratory Disease
COPD
Pneumonia
COPD
Asthma
Asthma, Boys
Asthma, Girls
Asthma, Children
Respiratory Disease
Respiratory Disease
Respiratory Disease
Respiratory Infection
Respiratory Disease
COPD
Respiratory Disease
COPD
Pneumonia
Asthma, Boys
Asthma, Girls
Asthma, Children
Respiratory Disease
Pollutant Effect Estimate (95% Cl)
P M2 5 | PM2 5 Adjusted for Gases and Other Size Fractions
PM2.5+PM10.2.5 r*-
PM.T .
pM.-j-rn Qn. |\p. n. ,, ,
PM-- , •
pM.-*rru.n,4.|\|n.4.Qn. , .
PM-- i . V
PM--+PM10-- i •
PM-+rr> ,
PM--+n. .

PM-rJ-SO- ' •
PMls ' 	 • 	
PM-.4-n, • .
PM25+S02 	 « 	
PM25+N02 	 . 	
PM25+CO , 	 . 	
PM25 ,-^
PM25+N02 _*_
PM2.5 , ——
PM25+CO , _^_
PM-- < . i
PM- : ,
piuu+rn so, MO, n, < ,
PM- ' .
PM"+<~), ^
PM2.5 -+-
PM25+03 .
PM25+N02 	 . 	
PM25+S02 !_._
PM25 .
PM,, .
PM,,+n, , ,
PM1lM5 Adjusted for Gases and other Size Fractions
PM1M.5+PM2.5 *
PM • V/
PH +rn cr> Mn n ' •

PM +rn+n +MH +°n ' •
PM ' • V7
rMm.^ , • ^/



PM +SO i •

pMr._+QO so- [\JQ- 0- '/ • >


PMr - -+SO- •
pjyi^^+lvjO^ «
p|y||C^r+QQ . 9
PM,--- •

PM|^25+S02 •
p[y||C^2r+[\j02 t
pM,-,rJ.pQ -

PMiri-r • ' *JI
p|y|r2r+rn gn2 |\|n2 n. ,
PMW25+03 	 . 	
PM1M5+N02 — i— « 	
PMW25+S02 	 . 	
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 // 1
-8-40 4 8 12 16 20 24 28 32 36 60
                                                 Excess Risk Estimate
Figure 6-15.
Excess risk estimates per 10 ug/m3 increase in 24-h avg PM2.6, and PMi0.2.sfor
respiratory disease ED visits or HAs, adjusted for co-pollutants.
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6.3.9.   Respiratory Mortality

      An evaluation of studies that examined the association between short-term exposure to PM2.5
and PMio_2.5 and mortality provides additional evidence for PM-related respiratory health effects.
Although the primary analysis in the majority of mortality studies evaluated consists of an
examination of the relationship between PM2 5 or PMio_2.s and all-cause (nonaccidental) mortality,
some studies have examined associations with cause-specific mortality including respiratory-related
mortality.
      Multicity mortality studies that examine the PM-respiratory mortality relationship on a
national scale - Franklin et al. (2007, 091257): 27 U.S. cities and Zanobetti and Schwartz (2009,
188462): 112 U.S. cities - have found consistent positive associations between short-term exposure
to PM2.5 and respiratory mortality of approximately  1.68% per  10 (ig/m3 at lag 0-1 (Section 6.5). The
associations observed on a national scale are consistent with those presented by Ostro et al. (2006,
087991) in a study that examined the PM2.5-mortality relationship in nine California counties (2.2%
[95% CI: 0.6-3.9] per 10 (ig/m3). An evaluation of studies that  examined additional  lag structures of
associations found smaller respiratory mortality  effect estimates when using the average of lag days
1 and 2 (1.01% [95% CI: -0.03 to 2.05] per 10 (ig/m3) (Franklin et al., 2008, 155779). and
associations consistent with those observed at lag 0-1 when examining single-day lags, specifically
lag 1 (1.78% [95% CI: 0.2-3.36]). Although the overall effect estimates reported in  the multicity
studies evaluated are consistently positive, it should be noted that a large degree of  variability exists
between cities when examining city-specific effect estimates potentially due to differences between
cities and regional differences in PM2.5 composition (Figure 6-25). Only a limited number of studies
that examined the PM2.5-mortality relationship have conducted analyses of potential confounders,
such as gaseous copollutants, and none examined the effect of copollutants on PM2  5 respiratory
mortality risk estimates. Although the recently evaluated multicity studies did not extensively
examine whether PM2 5 mortality risk estimates are  confounded by gaseous pollutants, evidence
from the limited number of single-city studies evaluated in the 2004 PM AQCD (U.S. EPA, 2004,
056905) suggest that gaseous copollutants do not confound the PM2 5-respiratory mortality
association. This is further supported by studies that examined  the PMi0-mortality relationship in
both the 2004 PM AQCD (U.S. EPA, 2004, 056905) and this review.  Overall, the respiratory PM2.5
effects observed in the new studies  evaluated were larger, but less precise than those reported for all-
cause (nonaccidental) mortality (Section 6.5), and are consistent with the  effect estimates observed
in the single- and multicity studies evaluated in the  2004 PM AQCD (U.S. EPA, 2004, 056905).
      Zanobetti and Schwartz (2009, 188462) also examined PMi0_2.5 mortality associations in 47
U.S. cities and found evidence for respiratory mortality effects (1.16% [95% CI: 0.43-1.89] per
10 (ig/m3 at lag 0-1), which are somewhat larger than those reported for all-cause (nonaccidental)
mortality (0.46% [95% CI: 0.21-0.671] per 10 ug/m3). In addition, Zanobetti and Schwartz (2009,
188462) reported seasonal (i.e., larger in spring) and regional differences  in PMi0_2.s respiratory
mortality risk estimates. However, single-city studies conducted in Atlanta, GA (Klemm  et al., 2004,
056585) and Vancouver, Canada ((Villeneuve  et al., 2003, 055051) reported no associations between
short-term exposure to PMi0_2.s and respiratory mortality. The difference in the results observed
between the multi- and single-city studies could be  due to a variety of factors including differences
between cities and compositional differences in PMi0_2.5 across  regions (Figure  6-30).  Only  a small
number of studies have examined potential confounding by gaseous copollutants or the influence of
model specification on PMi0_2 5 mortality risk estimates, but the effects are relatively consistent with
those studies evaluated in the 2004 PM AQCD (U.S. EPA, 2004, 056905).


6.3.10.  Summary  and Causal Determinations



6.3.10.1.  PM2.5

      Several studies of the effect of PM25 on hospital admissions for respiratory diseases reviewed
in the 2004 AQCD (U.S. EPA, 2004,  056905) reported positive associations for several diseases. The
2004 AQCD (U.S. EPA, 2004, 056905) presented limited epidemiologic evidence of PM25 being
associated with respiratory symptoms (including cough, phlegm, difficulty breathing, and
bronchodilator use); observations for PM2 5 were positive, with slightly larger effects for PM2 5 than
December 2009                                 6-149

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for PM10. In addition, mortality studies reported relatively higher PM2.5 risk estimates for respiratory-
related mortality compared to all-cause (nonaccidental) mortality. Controlled human exposure
studies did not provide support for effects of CAPs on respiratory symptoms. Small decrements in
peak flow for both PM25 and PMi0 in asthmatics and nonasthmatics were reported in epidemiologic
studies included in the 2004 PM AQCD (U.S. EPA, 2004, 056905). whereas controlled human
exposure and animal toxicological studies reported few or no effects on pulmonary function with
inhalation of CAPs. In addition, the 2004 PM AQCD (U.S. EPA, 2004, 056905) presented a number
of controlled human exposure and toxicological studies that reported mild pulmonary inflammation
following exposure to PM2 5 CAPs and DE or DE particles, as well as ROFA or other
metal-containing PM in animals. The 2004 PM AQCD (U.S. EPA, 2004, 056905) described
controlled human exposure studies showing increases in allergic responses among previously
sensitized atopic subjects after short-term exposure to DE particles. These observations were
supported by many toxicological studies that added to existing evidence demonstrating that various
types of PM could promote allergic disease and exacerbate allergic asthma in animal models.
Toxicological studies also indicated that PM2.5 increased susceptibility to respiratory infection.
      Overall, in recent studies PM2 5 effects on respiratory hospitalizations and ED visits have been
consistently observed. Most effect estimates were in the range of-1-4% and  were observed in areas
with mean 24-h PM25 concentrations between 6.1 and 22 (ig/m3. Further, recent studies have focused
on increasingly specific disease endpoints such as asthma, COPD, and respiratory infection. The
strongest recent evidence of an association comes from large multicity studies of COPD, respiratory
tract infection, and all respiratory diseases among Medicare recipients (>65 yr) (Bell et al., 2008,
156266; Dominici et al., 2006, 088398). Studies of children have also found evidence of an effect of
PM2 5 on hospitalization for all respiratory diseases, including asthma and respiratory infection.
However,  many of these effect estimates are imprecise, their magnitude and statistical significance
are sensitive to choice of lag, and some null associations were observed. Although the association of
PM25 with pediatric asthma was not examined specifically, it is noteworthy that one of the strongest
associations observed in the Atlanta-based  SOPHIA study was between PMi0 and pediatric asthma
visits; PM25 makes up a large proportion of PMi0 in Atlanta (Peel et al., 2005, 056305). Positive
associations between PM25 (or PMi0) and hospital admissions for respiratory infection ( Figure 6-14)
are supported by animal toxicological studies which add to previous findings of increased
susceptibility to infection following exposure to PM2 5. These include studies demonstrating reduced
clearance of bacteria (Pseudomonas, Listeria) or enhanced pathogenesis of viruses (influenza, RSV)
after exposure to DE or ROFA.
      Epidemiologic studies that examined the association between PM2 5 and mortality provide
additional evidence for PM25-related  respiratory effects (Section 6.3.9). The multicity studies
evaluated found consistent, precise positive associations between short-term exposure to PM2 5 and
respiratory mortality ranging from 1.67 to 2.20% increases at mean 24-h PM25 avg concentrations
above 13 (ig/m3. Although only a limited number of studies examined potential confounders of the
PM2 5-respiratory  mortality relationship, the studies evaluated in both this review and the 2004 PM
AQCD (U.S. EPA, 2004, 056905) support an association  between short-term exposure to PM25 and
respiratory mortality.
      Epidemiologic studies of asthmatic children have observed increases in respiratory symptoms
and asthma medication use associated with higher PM2 5 or PM10 concentrations. Associations with
respiratory symptoms and medication use are less consistent among asthmatic adults, and there is no
evidence to suggest an association between respiratory symptoms with PM2 5 among healthy
individuals. In addition, respiratory symptoms have not been reported following controlled
exposures to PM2 5 among healthy or  health-compromised adults (Section 6.3.1.2).
      Although more recent epidemiologic studies of pulmonary function and PM25 have yielded
somewhat inconsistent results, the majority of studies have found an association between PM25
concentration and FEVi, PEF, and/or  MMEF. In asthmatic children, a 10 ug/m3 increase in PM25 is
associated with a decrease in FEVi ranging from 1-3.4%  (Section 6.3.2.1). A limited number of
controlled human exposure studies have reported small decreases in arterial oxygen saturation and
MMEF following exposure to PM2 5 CAPs with more pronounced effects observed in healthy adults
than in asthmatics or older adults with COPD (Section 6.3.2.2).  In toxicological studies, changes in
pulmonary function have been observed in healthy and compromised rodents after inhalation
exposures to CAPs from a variety of locations or DE. A role for the PM fraction of DE is supported
by altered pulmonary function in healthy rats after IT instillation of DE particles (Section 6.3.2.3).
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      Several lines of evidence suggest that PM2.5 promotes and exacerbates allergic disease, which
often underlies asthma (Section 6.3.6). Although epidemiologic studies examining specific allergic
outcomes and short-term exposure to PM are relatively rare, the available studies, conducted
primarily in Europe, positively associate PM2.5 and PMio with allergic rhinitis or hay fever and skin
prick reactivity to allergens. Short-term exposure to DE particles in controlled human exposure
studies has been shown to increase the allergic response among previously sensitized atopic subjects,
as well as induce de novo sensitization to an antigen. Toxicological studies continue to provide
evidence that PM2.5, in the form of CAPs, resuspended DE particles, or DE, but not wood smoke,
spurs and intensifies allergic responses in rodents. Proposed mechanisms for these effects include
mediation by neurotrophins and oxidative stress, and one study demonstrated that effects were
mediated at the  epigenetic level (Liu et al., 2008, 156709).
      A large body of evidence, primarily from toxicological studies, indicates that various forms of
PM induce oxidative stress, pulmonary injury, and inflammation. Notably, CAPs from a variety of
locations induce inflammatory responses in  rodent models, although this generally requires multiday
exposures.  The toxicology findings are consistent with  several recent epidemiologic studies of PM2.5
and the inflammatory  marker eNO, which reported statistically significant, positive effect estimates
with some inconsistency in the lag times and use of medication. In asthmatic children, a 10 ug/m3
increase in PM25 is associated with an increase in eNO ranging from 0.46 to 6.99 ppb. Several new
controlled human exposure studies report traffic or DE-induced increases in markers of inflammation
(e.g., neutrophils and IL-8) in BALF from healthy adults. Recent studies have provided additional
evidence in support of a pulmonary oxidative response to DE in humans, including induction of
redox-sensitive transcription factors and increased urate and GSH concentrations in nasal lavage. In
addition, exposure to wood smoke has recently been demonstrated to increase the levels of eNO and
malondialdehyde in breath condensate of healthy adults (Barregard et al., 2008, 155675).
Preliminary findings indicate little to no pulmonary injury in humans following controlled exposures
to PM25 urban traffic particles or DE, in contrast to  a number of toxicological studies demonstrating
injury with CAPs or DE (Sections 6.3.5.2 and 6.3.5.3, respectively).
      Recent studies have reported associations of hospital admissions, ED or urgent care visits for
several respiratory diseases with PM2 5 components  and sources including Ni, V, OC  and EC, wood
smoke and traffic emissions, in studies of both children and adults. Delfmo et al. (2003,  090941;
2006, 090745) found positive associations between  EC and OC components of PM and asthma
symptoms and between EC and eNO. Particle composition and/or source also appears to heavily
influence the increase in markers of pulmonary  inflammation demonstrated in studies of controlled
human exposures to PM2 5. For example, whereas exposures to PM2 5 CAPs from Chapel Hill, NC
have been shown to increase BALF neutrophils in healthy adults, no such effects have been observed
in similar studies conducted in Los Angeles. In addition, differential inflammatory responses have
been observed following bronchial instillation of particles  collected at different times or from
different areas (Section 6.3.3.2). One new study found that the increased airway neutrophils
previously  observed by Ohio et al. (2000, 012140) in human volunteers after Chapel  Hill CAPs
exposure could be largely attributed to the content of sulfate, Fe, and Se in the soluble fraction
(Huang etal. 2003. 0873771
      In  summary, new evidence of ED visits and hospital admissions builds upon the positive and
statistically significant evidence presented in the 2004 PM AQCD to support a consistent association
with ambient concentrations of PM25 Most effect estimates with respiratory hospitalizations and ED
visits were in the range of-1-4% and were observed in areas with mean 24-h PM25 concentrations
between  6.1 and 22 ug/m3. The evidence for PM2 5-induced respiratory effects is strengthened by
similar hospital admissions and ED visit associations for PMi0, along with the consistent positive
associations observed between PM2 5 and respiratory mortality in multicity studies. Panel studies also
indicate associations with PM2 5 and respiratory symptoms, pulmonary function, and  pulmonary
inflammation among asthmatic children. Further support for these observations is provided by recent
controlled human exposure studies in adults demonstrating increased markers of pulmonary
inflammation following DE and other traffic-related exposures, oxidative responses to DE and wood
smoke, and exacerbations of allergic responses and  allergic sensitization following exposure to DE
particles. Although not consistent across studies, some controlled human exposure studies have
reported  small decrements in various measures of pulmonary function following exposures to PM25.
Numerous toxicological studies demonstrating a wide range of responses provide biological
plausibility for the associations between PM2 5 and respiratory morbidity observed in epidemiologic
studies. Altered pulmonary function, mild pulmonary inflammation and injury, oxidative responses,
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AHR in allergic and non-allergic animals, exacerbations of allergic responses and increased
susceptibility to infections were observed in a large number of studies involving exposure to CAPs,
DE, other traffic-related PM, and wood smoke. The evidence for an effect of PM2.5 on respiratory
outcomes is somewhat restricted by limited coherence between some of the findings from
epidemiologic and controlled human exposure studies for the specific health outcomes reported and
the sub-populations in which those health outcomes occur. For instance, although there is evidence
for respiratory symptoms among asthmatic children in epidemiologic panel studies, the studies of
hospital admissions and ED visits  provide more evidence for effects from COPD and respiratory
infections than for asthma. Additionally, controlled human exposure studies report greater effects in
healthy adults when compared to asthmatics or those suffering from COPD. Finally, there is limited
information which could explain the relationship between the clinical and subclinical respiratory
outcomes observed and the magnitude of the PM2 5-respiratory mortality associations reported.
Therefore, the evidence is sufficient to conclude that  a C3USal relationship JS likely to exist
between short-term PM25 exposures and respiratory effects.


6.3.10.2. PM10.2.5

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) presented the results from several
epidemiologic studies of respiratory symptoms and PMi0_2.5, which provided limited evidence for
cough and effects on morning PEF. Toxicology data for PMi0_2.5 were extremely limited, and there
were no controlled human exposure studies presented in the 2004 PM AQCD (U.S. EPA, 2004,
056905) that evaluated the effect of PM10_2.5  on respiratory symptoms, pulmonary function, or
inflammation. Epidemiologic studies of the effect of  PMi0_2.s on hospitalizations or ED visits for
respiratory  diseases (i.e., pneumonia, COPD and respiratory diseases combined) reviewed in the
2004 AQCD (U.S. EPA, 2004, 056905) reported positive associations. Additionally, the few
mortality studies that examined cause-specific mortality suggested somewhat larger risk estimates
for respiratory mortality compared to all-cause (nonaccidental) mortality.
      Several new studies report associations between PMi0_2.s and respiratory hospitalizations with
the most consistent evidence among children (Figure 6-10 through  Figure 6-14), however, effect
estimates are imprecise. Although  a number  of studies provide evidence of respiratory effects in
older adults, a recent analysis of MCAPS data reports that weak associations of PMi0_2.5 with
respiratory  hospitalizations are further diminished after adjustment for PM2 5. It is not clear that
PMio_2.5 estimates across all populations and regions are confounded by PM2 5. An examination of
PM10_2.5 mortality associations on a national scale found a strong association between PM10_2.5 and
respiratory  mortality, but this association varied when examining city-specific risk estimates
(Zanobetti  and Schwartz, 2009, 188462). The regional variability in PMi0_2.5 mortality risk estimates
is further confirmed by the negative associations reported in the single-city studies evaluated.
However, there is greater spatial heterogeneity in PMi0_2.5 compared to PM2 5 and consequently
greater potential  for exposure measurement error in epidemiologic studies relying on central site
monitors. This exposure measurement  error may bias effect estimates toward the null and could
explain some of the regional  variability in the observed associations between PMi0_2.5 and respiratory
morbidity and mortality.
      Mar et al. (2004, 057309) provide evidence for an association with increased respiratory
symptoms in asthmatic children, but not asthmatic adults. Consistent with this, controlled human
exposures to PMi0_2.5 have not been observed to affect lung function or respiratory symptoms in
healthy or asthmatic adults. However, increases in markers of pulmonary inflammation have been
demonstrated in healthy volunteers. In these studies,  an increase in neutrophils in BALF or induced
sputum was observed, with additional evidence of alveolar macrophage activation associated with
biological components of PMi0_2.5  (i.e., endotoxin). Toxicological studies using inhalation exposures
are still lacking, but pulmonary injury and inflammation have been observed in animals after IT
instillation  exposure and both rural and urban PMi0_2.5 have induced these responses. In some cases,
PM10_2.5 from urban air was more potent than PM25 (Section 6.3.3.3). PM10_2.5 respiratory effects may
be due to components other than endotoxin (Wegesser and Last, 2008, 190506).
      Overall, the most compelling new evidence comes from a number of recent epidemiology
studies conducted in Canada and France showing significant associations between respiratory ED
visits or hospitalization and short-term exposure to PMi0_2.5. Effects have been observed in areas
where the mean 24-h avg PMi0_2.5  concentrations ranged from 7.4 to 13.0 ug/m3. The strongest
relationships were observed among children, whereas studies of adults and older adults show less
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consistent evidence of an association. While controlled human exposure studies have not observed
an effect on lung function or respiratory symptoms in healthy or asthmatic adults in response to
exposure to PMi0_2.5, healthy volunteers have exhibited increases in markers of pulmonary
inflammation. Toxicological studies using inhalation exposures are still lacking, but pulmonary
injury has  been observed in animals after IT instillation exposure to both rural and urban PMi0_2.5,
which may not be entirely attributed to endotoxin. Overall, epidemiologic studies, along with the
limited number of controlled human exposure and toxicological studies that examined PMi0_2.5 and
respiratory outcomes, provide evidence that is Suggestive Of 3 C3USal relationship between
short-term PM1025 exposures and respiratory effects.


6.3.10.3.  UFPs

     The 2004 PM AQCD (U.S. EPA, 2004, 056905) included a few epidemiologic and controlled
human exposure  studies that examined the effect of UFPs on respiratory morbidity. Collectively
these studies provided limited evidence of an association between UFPs and respiratory symptoms,
medication use, inflammation, and decreased pulmonary function.  Evidence from toxicological
studies presented in the 2004 AQCD, although limited, suggested that exposure via inhalation to
high concentrations of UF TiO2 may increase pulmonary inflammation in healthy rodents. Since the
publication of the 2004 AQCD there has been an increased focus among the scientific community on
gaining a better understanding of the potential health effects associated with exposure to UFPs
(U.S. EPA, 2004, 056905). A number of recent controlled human exposure and toxicological studies
have evaluated respiratory responses following exposures to UF CAPs, model particles, and fresh
diesel or gasoline exhaust. While DE contains both PM2.5 and UFPs, the MMAD is typically
< 100 nm, and therefore the results of these studies may be used to support findings from studies
utilizing other sources of UFP.
     UFPs were associated with incident wheezing symptoms among infants (<1 yr) in a study
conducted in Copenhagen, Denmark, where the mean UFP number concentration was 8,092
particles/cm3, though this association did not persist for children between ages  1-3 yr (Andersen et
al., 2008, 096150). Recent epidemiologic studies conducted in Copenhagen, Denmark and Helsinki,
Finland, reported associations between UFPs and hospital admissions or ED visits for respiratory
diseases, including childhood asthma and pneumonia in adults (Andersen et al., 2008, 189651;
Halonen et al., 2008, 189507). The median UFP number concentrations in Copenhagen and Helsinki
were 6,243 particles/cm3 and 8,203 particles/cm3, respectively. Associations between UFP and ED
visits for respiratory diseases were not observed in the Atlanta-based SOPHIA study, where the mean
UFP number concentration was 38,000 particles/cm3.
     A single recent epidemiologic study has examined associations between UFP and pulmonary
function, and observed that asthmatic adults exhibited decreased lung function  after exposure to
diesel traffic pollution in London (McCreanor et al., 2007, 092841). Two new  controlled human
exposure studies  have reported small decreases in pulmonary function among healthy adults
approximately  following exposure to Los Angeles UF CAPs or UF EC (Gong et al., 2008, 156483;
Pietropaoli et al., 2004, 156025). Exposures to lower concentrations of UF CAPs from Chapel Hill,
NC did not result in any changes in pulmonary function (Samet  et al., 2009, 191913). However,
while Gong et al. (2008, 156483) did not observe any effect of exposure to UF  CAPs on markers of
pulmonary inflammation, Samet et al. (2009, 191913) reported an UF CAPs-induced increase in IL-
8 in BALF at 18 hours post-exposure. A limited number of controlled human exposure studies  have
also demonstrated increases in the pulmonary inflammatory response following exposure to UF and
PM2.5 from DE, which may be enhanced by exposure to O3 (Section 6.3.3.2).
     Altered pulmonary function and inflammation have also been observed in toxicological studies
of DE and UF model particles (Sections 6.3.2.3 and 6.3.3.3). In one rat model,  pulmonary
inflammation was observed after exposure to UF CB at concentrations as low as 180 (ig/m3 (Harder
et al., 2005, 087371). However, inflammatory responses vary  considerably depending on the animal
model, dose, test material, and exposure duration. In cases where pulmonary inflammation was not
observed, oxidative stress was often evident (Section 6.3.4.2). Oxidative stress  is a major mechanism
by which PM may exert effects (Chapter 5), and some toxicological studies suggest that UFPs  are
more potent than PM2.5, possibly due to a higher proportion of pro-oxidative OC and PAH content
and greater surface area with which to deliver these components.
     The relationship between exposure to  UFP and pulmonary injury has not been widely
examined. No association with pulmonary injury biomarkers was found for UFP in a European
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multicity epidemiologic study (Timonen et al., 2004, 087915). In controlled human exposure
studies, UFP from wood smoke resulted in significantly increased markers of injury in healthy
adults, but this effect was not evident in COPD sufferers exposed to DE (Section 6.3.5.2). Exposure
of neonatal rats to UF iron-soot particles resulted in a significantly reduced rate of cell proliferation
in the proximal alveolar region, which suggests that postnatal lung development may be susceptible
to air pollution, consistent with impaired lung function growth observed in children (Pinkerton et
al., 2004, 087465). In contrast, no histopathological responses were evident in adult mice exposed to
UF iron-soot particles (Last et al., 2004, 097334). Some toxicological studies have reported
pulmonary injury after inhalation of DE or gasoline exhaust (Section 6.3.5.3). In studies that
evaluated ambient PM size fractions from a variety of European and U.S. cities for relative toxicity
in rodents following IT instillation exposure, UFPs were generally less injurious than the larger size
fractions. However, the UF fraction of Montana coal fly ash induced greater injury and inflammation
than the PMio_2.5 fraction (Gilmour et al., 2004, 057420).
      In rodent studies, UF CAPs appeared to be more potent than PM2.5 CAPs in inducing and
exacerbating allergic responses (Section 6.3.6.3). In addition to CAPs, UF CB or iron-soot particles,
but not particles from fresh gasoline exhaust, have been shown to induce or exacerbate allergic
responses in mice. Bacterial clearance appears unaffected by hardwood smoke or gasoline engine
exhaust. However, host defenses are impaired by DE, which has been shown to reduce bacterial
clearance, impair defenses against viral infection, and  reduce thymus weight, indicating systemic
immunosuppression.
      Several toxicological studies demonstrated oxidative, inflammatory, and allergic responses
following exposure to a number of different UFP types, including model particles (i.e., CB, iron-soot
particles), CAPs, and DE. Although the respiratory effects of controlled exposures to UFPs have  not
been extensively examined in humans, two controlled  human exposure studies have observed small
UFP-induced decreases in pulmonary function; however, no increases in respiratory symptoms have
been reported. In a limited number of studies, markers of pulmonary inflammation were increased
following controlled human exposures to UFP, which has been most consistently observed in studies
using fresh DE. In both controlled human exposure and animal toxicological studies using fresh DE,
the relative contributions of gaseous copollutants to the observed effects remain unresolved.
However, similar effects are reported using resuspended DE particles, and although not UFPs, these
particles can be assumed to have similar composition.  A limited number of epidemiologic studies
have provided some evidence of an association between short-term exposure to UFPs and respiratory
symptoms,  as well as asthma hospitalizations. However, the interpretation of these findings is
difficult due to the spatial variability of UFPs. Thus, the current collective evidence is SUgQBStJVB
of a causal relationship between short-term UFP exposure and respiratory effects.



6.4.  Central Nervous System  Effects

      While evidence of an effect of PM on the CNS was not presented in the 2004 PM AQCD
(U.S. EPA,  2004, 056905). a limited number of recent epidemiologic, controlled human exposure
and toxicological studies provide some evidence that exposure to PM may be associated with
changes in neurological function. The majority of studies included in this section are of short-term
exposure, however, there are also a few studies of long-term exposure. As CNS effects of PM are a
newly emerging area, and since there are so few  studies, all studies that evaluate CNS responses  are
included in this section.


6.4.1.   Epidemiologic Studies

      Chen and Schwartz (2009, 179945) used extant  data on CNS function from the Third National
Health and Nutrition Examination Survey (NHANES III) to characterize the association between
cognitive function in adults (ages 20-59 yr) and exposure to ambient air pollution. Three
computerized neurobehavioral tests were used: a simple reaction time test (SRTT), a basic measure
of visuomotor speed; a symbol digit substitution test (SDST) on coding ability; and a serial digit
learning test (SDLT) on attention and short-term memory. The authors used annual PMi0
concentrations to approximate the long-term  exposure to ambient air pollution prior to the
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NHANES-III examination. Increased PM10 levels were associated with reduced performance in all
three neurobehavioral tests, and were particularly strong for SDST and SDLT scores in models
adjusted for age and sex. However, after additional adjustment for race/ethnicity or SES, the
magnitudes of these associations were greatly diminished and largely null. It is possible that the
observed associations disappeared after adjustment for race/ethnicity and SES due to the potential
confounding by residential segregation of ethnic minorities and poorer people in areas with high
levels of ambient PMi0 concentrations.
      Two additional epidemiologic  studies evaluated the effect of ambient PM on the CNS
(Calderon-Garciduefias et al., 2008,  156317; Suglia et al, 2008, 157027). These studies examined
long-term exposure to non-specific PM indicators and are detailed in Annex E.


6.4.2.  Controlled Human Exposure Studies

      In a recent controlled human exposure study, Cruts et al. (2008, 156374) exposed 10 healthy
males (18-39 yr) to filtered air and dilute DE (300 ug/m3 PM) for 1 h using a randomized crossover
study design. Changes in brain activity were measured during and following exposure using
quantitative electroencephalography  (QEEG). Exposure to DE was observed to significantly increase
the median power frequency (MPF) in the frontal cortex during exposure, as well as in the hour
following the completion of the exposure. While this study does provide some evidence of an acute
cortical stress response to DE, it is important to note that the QEEG findings are very nonspecific,
and could have been caused by factors other than diesel PM such as DE gases (e.g., CO, NO and
NO2) or the odor of the DE.


6.4.3.  lexicological Studies

      Evidence is mounting that the  CNS may be a critical target of PM and that adverse health
effects may result from PM exposure. Whether these health effects are a direct or indirect effect of
PM has not yet been established. One hypothesis suggests that UFPs which deposit onto nasal
olfactory epithelium enter the  CNS by axonal olfactory transport to the olfactory bulb and lead to a
cascade of effects involving inflammatory cytokines and ROS. An increased potential for
neurodegenerative processes may ensue.  Evidence for translocation of UFPs to the olfactory bulb via
olfactory neurons is discussed in Chapter 4, but its relevance to CNS health effects is unknown.
Another hypothesis suggests that brain inflammation occurs secondarily to PM-mediated systemic
inflammation. Finally, it has been suggested that PM-stimulation of the ANS via respiratory tract
receptors results in inflammatory or other effects in the CNS. This is an emerging field with many
unknowns.


6.4.3.1.   Urban Air

      Calderon-Garciduenas et al.  (2003, 156316) conducted a long-term observational study in
mongrel dogs from Mexico City and Tlaxcala. DNA damage and inflammation in the brain and
respiratory tract were evaluated in dogs living in Mexico City (exposed group) and dogs living in
Tlaxcala (control group). These cities are similar in altitude but differ in air pollutant levels.
Measurements of air pollutant levels were presented only for Mexico City, the more polluted city.
Statistically significant greater levels of apurinic/apyrimidinic sites (an indicator of DNA damage)
were observed in the olfactory bulbs and hippocampus of Mexico City dogs compared with controls.
These differences were not seen in other brain regions examined or in nasal respiratory epithelium.
In addition, Mexico City dogs demonstrated greater histopathological  changes in the respiratory and
olfactory epithelium of the nasal cavity compared with controls. Immunohistochemical staining of
brain tissue from the Mexico City  dogs demonstrated greater immunoreactivity for NF-KB, iNOS,
cyclooxygenase-2, glial fibrillatory acidic protein (GFAP), ApoE, amyloid precursor product and
p-amyloid compared with controls. These results are indicative of inflammation and stress protein
responses. This  study has several limitations given that the dogs were of mixed breeds and of
variable ages and that there was no standardization of exposures or diets. However results suggest a
possible relationship between  air pollution and brain inflammation.
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6.4.3.2.   CAPs

      Several new inhalation studies have provided evidence of CNS effects due to ambient PM
exposures. In one study, Campbell et al. (2005, 087217) exposed OVA-sensitized BALB/c mice to
filtered air or near-highway Los Angeles CAPs (a 20-fold concentration of PM2.5+UFPs or UFPs
only; mean exposure concentration UFPs 282.5 ug/m3 and PM2.5 441.7 ug/m3) for 4 h/day and 5
days/wk over a 2-wk period. The animals were subsequently challenged with OVA to elicit an
allergic response in the lungs; brain tissue was obtained one day later.  Exposure to CAPs, but not
filtered air, resulted in activation of the immune-related transcription factor NF-KB and upregulation
of the cytokines TNF-a, and IL-la in the brain, demonstrating pro-inflammatory responses that
could contribute to neurodegenerative disease. While this study demonstrates CAPs effects in an
allergic animal model, it is not known whether these responses also occur in non-allergic animals.
      In a second study, control or OVA-sensitized and challenged Brown Norway rats were exposed
for 8 h to filtered air or PM2.5 CAPs (500 ug/m3) in Grand Rapids, MI (Sirivelu  et al., 2006,
111151). Brain tissue was obtained 1 day later. CAPs exposure resulted in brain region-specific
modulation of neurotransmitters. In animals which were not pretreated with OVA, statistically
significant increases in norepinephrine were observed in the paraventricular nucleus and olfactory
bulb of CAPs-exposed rats compared with filtered air controls. In animals which were pretreated
with OVA, a statistically significant increase in dopamine was observed in the medial preoptic area
in CAPs-exposed rats compared with controls. Furthermore, exposure to CAPs resulted in a
statistically significant increase in serum corticosterone. These data suggest that the
hypothalamo-pituitary-adrenal axis (i.e., stress axis)  may be activated  by PM exposure,  causing
aggravation of allergic airway disease. The authors discuss the possible role of the olfactory bulb in
mediating neuroendocrine control of autonomic activities involved in respiratory and cardiovascular
functions; however these relationships require clarification.
      Pro-inflammatory responses were examined in a subchronic CAPs study involving normal
(C57BL/6J) and ApoE"" mice (Kleinman et al., 2008, 190074). Mice were exposed to filtered air or
to two concentrations of UF CAPs from a near-highway area of central Los Angeles (average of 30.4
and 114.2 ug/m3) for 5 h/day and 3 days/wk over a 6-wk period. Brain tissue was harvested one day
after the last exposure and cortical samples prepared. CAPs exposure resulted in activation of
transcription factors, with a dose-dependent increase observed for AP-1 and an increase in NF-KB
observed at the higher concentration. Increased levels of GFAP (representing activation of
astrocytes) and phosphorylated JNK  (representing MAP kinase activation) were observed at the
lower but not higher concentration of CAPs. No changes were observed in levels of or activation of
the other MAP kinases p38 and ERK or of 1KB. These findings provide evidence that inhalation of
CAPs can lead to activation of cell signaling pathways involved in upregulation of pro-inflammatory
cytokine genes in the cortical region  of the mouse brain.
      In another study utilizing normal (C57BL/6) and ApoE"" mice, brain histopathology was
examined following a 4-month  chronic exposure to PM2.5 CAPs from Tuxedo, NY (March, April or
May through September 2003) (Veronesi  et al., 2005, 087481). The average PM25 exposure
concentration was 110 ug/m3. CAPs exposure resulted in a statistically significant decrease in
dopaminergic neurons, measured by tyrosine hydroxylase immunoreactivity, in the substantia nigra
of ApoE"7" mice but not in  control mice. This population of neurons is targeted in neurodegenerative
diseases such as Parkinson's. Furthermore, a statistically significant increase in GFAP
immunoreactivity, a marker for astrocytes, was observed in the nucleus compacta of CAPs-exposed
ApoE"7" mice compared to air-exposed ApoE"7" mice.  These results suggest that the ApoE"7" mice, a
genetic model involving increased oxidative stress, are susceptible to PM-induced
neurodegeneration. Evidence for brain  oxidative stress has also been found in normal animals
following IT instillation of high concentrations of PM25 from Taiyuan, China (Liu and Meng, 2005,
088650) and of gasoline exhaust (Che  et al., 2007, 096460) and following chronic exposure to
ROFA by intranasal instillation (Zanchi et al., 2008, 157173).


6.4.3.3.   Diesel Exhaust

      A recent study tested the effects of DE inhalation on spatial learning and memory function-
related gene expression in the hippocampus (Win-Shwe et al., 2008, 190146). Male BALB/c mice
were exposed to DE (148.86  ug/m3 PM) for 5 h/day and 5 day/wk over a 4-wk period. Particle size
was 26.21±1.50 nm and PNC was 1.92xl06 ± 6.18><104 particles/m3. Concentrations of gases were
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3.27 ppm CO, 0.01 ppm SO2, 0.53 ppmNO?, 0.98 ppm NO and 0.07 ppm CO2. Half of the animals
were injected i.p. once per week with lipoteichoic acid (LTA), a bacterial cell wall component used
to induce systemic inflammation. The ability of the mice to perform spatial learning tasks was
examined the day after the final exposure to DE and on two subsequent days. Impaired acquisition of
spatial learning was observed in DE-exposed mice on the first day and on all three days in DE-
exposed mice that had also been treated with LTA. LTA by itself had no effect. Since the NMD A (a
type of neurotransmitter) receptors in the hippocampus play an important role in spatial learning
ability, mice were sacrificed and total RNA from hippocampus was extracted and analyzed for
expression of NMD A receptor subunits. DE exposure resulted in a statistically significant increase in
the expression of one subunit while the combined exposure to DE and LTA resulted in statistically
significant increases in the expression of three subunits compared with controls. The expression of
pro-inflammatory cytokines  was also examined in the hippocampus. DE exposure resulted in a
statistically significant increase in TNF-a mRNA, while LTA exposure resulted in a statistically
significant increase IL-1(3 mRNA compared with controls. Neither exposure altered the expression of
HO-1. These results demonstrated that subchronic exposure to UF-rich DE resulted in impaired
spatial learning and altered expression of hippocampal genes involved in memory function and
inflammation. These responses were modulated by systemic inflammation.


6.4.3.4.  Summary of lexicological Study Findings of CMS Effects

      In summary, PM may  produce adverse effects in the CNS by direct or indirect mechanisms
which are at present incompletely understood. Two recent short-term PM2.5 CAPs inhalation studies
demonstrated pro-inflammatory responses in the brain and brain region-specific modulation of
neurotransmitters and suggest the involvement of neuroimmunological pathways. One  recent chronic
PM2.5 CAPs inhalation study demonstrated loss of dopaminergic neurons in the substantia nigra and
suggested that oxidative stress contributes to neurodegeneration. Veronesi et al. (2005,  087481) have
noted that the brain is very vulnerable to the oxidative stress induced by  PM due to the brain's high
energy demands, low levels  of endogenous free radical scavengers, and high content of lipids and
proteins. PM-mediated upregulation of inflammatory cytokines and mediators may also contribute to
neurodegeneration. In fact, a recent subchronic study involving UF CAPs demonstrated the
activation of cell signaling pathways associated with upregulation of pro-inflammatory cytokines in
brain  cortical regions. Furthermore, a subchronic study involving UF-rich DE demonstrated impaired
spatial learning and altered expression of pro-inflammatory and neurotransmitter receptor genes in
the hippocampus. Further investigations  are required to delineate mechanisms involved in these
responses.


6.4.4.  Summary and Causal Determination

      Recent animal toxicological studies involving acute or chronic CAPs exposure have
demonstrated pro-inflammatory responses in the brain, brain region-specific modulation of
neurotransmitters and loss of dopaminergic neurons in the substantia nigra (Campbell  et al., 2005,
087217: Kleinman et al., 2008, 190074: Sirivelu  et al., 2006, 111151: Veronesi et al.,  2005,
087481). However, the mechanisms underlying these effects need to be delineated. A single
controlled human exposure study provides some evidence of an acute cortical stress response to DE,
though these findings are nonspecific and could have been caused by DE gases rather than DE
particles (Cruts  et al., 2008, 156374). Similar consideration is warranted for the single animal
toxicological study involving DE which demonstrated impaired spatial learning and altered
expression of pro-inflammatory and neurotransmitter genes in the hippocampus following
subchronic  exposure (Win-Shwe et al., 2008, 190146).  The single epidemiology study that
examined CNS outcomes did not find associations between long-term exposure to PMi0 and
cognitive function in adults after adjustment for race/ethnicity or SES (Chen  and Schwartz, 2009,
179945). Though the effect of ambient air pollution on CNS outcomes has recently begun to draw
more  attention, the evidence for a PM-induced CNS effect is limited. While most available studies
have evaluated the effects of fine particle exposures, there is insufficient evidence to draw
conclusions regarding effects of specific PM size fractions. Overall, the evidence JS inadequate to
determine if a causal relationship exists between short-term exposures to PM2.5, PM™ 25,
or UFPs and CNS effects.
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6.5.  Mortality
      The relationship between short-term exposure to PM and mortality has been extensively
addressed in previous PM assessments (U.S. EPA, 1982, 017610: 1996, 079380: 2004, 056905). A
positive association between PM concentration and mortality was consistently demonstrated across
studies cited in the 2004 PM AQCD (U.S. EPA, 2004, 056905): these results are summarized below
in Section 6.5.1. Numerous studies have been published since the previous review, including a
number of multicity analyses and many single-city studies. The current body of evidence examines
the association between short-term exposure to PM of various size fractions (i.e., PMi0, PMi0_2.5,
PM2.5, and UFPs) and mortality through the use of time-series and/or case-crossover studies. Both
study designs aim to disentangle  the PM-mortality effect through either complex modeling (i.e.,
time-series) or matching strategies (i.e., case-crossover). Overall, the results of the more recent
studies build upon the conclusions from the previous review, showing consistent positive
associations between mortality and short-term exposure to PM2.5 and PMi0_2.5.
      Section  6.5.2 reviews and summarizes the results of recent studies that examined mortality
associations with  the four PM size classes listed above. Each section integrates the results of recent
studies with those available in previous PM reviews. This assessment first focuses on multicity
studies that examined mortality associations with PMi0 because this is an important body of
literature that provides information on potential effect modifiers, potential confounding by
copollutants, evaluation of concentration-response relationships, and the influence of different
modeling approaches on the PM-mortality relationship (Section 6.5.2.1). ThePMio studies have
provided the most data among the PM indices thus far; therefore this evaluation begins with the
consideration of those findings as they relate to the general association between PM and mortality. It
is difficult to interpret the extent  to which these studies inform an evaluation of the effects of PM2.5
or PMio_2.5, since data are combined from multiple cities with different PM composition.
Interpretations of the PM size fraction that contributes the most to the PMi0 effects observed are
provided when appropriate in the following review. The multicity studies that examine the
association between PMi0 and mortality also offer new evidence on regional and seasonal differences
in effect estimates, building upon observations made in the 2004 PM AQCD (U.S. EPA, 2004,
056905).
      Recent study findings on associations with PM25!PMio_2.5, and UFPs are evaluated in Sections
6.5.2.2, 6.5.2.3, and 6.5.2.4, respectively. For PM2.5, the focus of the assessment remains on multicity
study findings; however, for PMi0_2.5 and UFPs, some additional emphasis is placed on single-city
studies, due to the relative sparseness of peer-reviewed literature on these size fractions. Some
studies have also evaluated relationships between mortality and specific components and sources of
PM,  and the results are summarized in Sections 6.5.2.4 and 6.5.2.5. Finally, Section 6.5.2.6 assesses
evidence on the concentration-response relationship between short-term PM exposure and mortality.


6.5.1.   Summary of Findings from  2004  PM AQCD

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) found strong evidence that PMi0 and PM2.5, or
one or more PM2 5 components, acting alone and/or in combination with gaseous copollutants, are
associated with total (nonaccidental) mortality and various cause-specific mortality outcomes. For
PMio, several multicity studies in the U.S., Canada, and Europe provided strong support for this
conclusion, reporting associations with total mortality highlighted by effect estimates ranging from
-0.2 to 0.7% (per 10 ug/m3 increase in PMi0) (U.S. EPA, 2004, 056905). Numerous studies also
reported PMi0 associations with cause-specific  mortality, specifically cardiovascular- and
respiratory-related mortality. For PM25, the strength of the evidence varied across categories of
cause-specific mortality, with relatively stronger evidence for associations with cardiovascular
compared to respiratory mortality. The resulting effect estimates reported from the U.S.- and
Canadian-based studies (both multi- and single-city) analyzed for these two categories ranged from
1.2 to 2.7% for cardiovascular-related mortality and 0.8 to 2.7% for respiratory-related mortality, per
10 ug/m3 increase in PM2.5 (U.S.  EPA, 2004, 056905). In regards to PMi0.2.5, the PM AQCD found a
limited body of evidence that was suggestive of associations between short-term exposure to ambient
PMio_2.5 and various mortality outcomes (e.g., 0.08-2.4% increase in total [nonaccidental] mortality
per 10 ug/m3 increase in PMi0_2.5). The positive effect estimates obtained from studies that analyzed
the association between PMi0_2.5 and mortality resulted in the conclusion that PMi0_2.5, or some
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constituent component(s) (including those on the surface) of PM10_2.5, may contribute, in certain
circumstances, to increased human health risks.
      Some additional studies examined the association between specific PM2.5 chemical
components and mortality. These studies  observed associations for SO42~, NO3", and CoH, but not
crustal particles. The strength of the association for each component varied from city to city
(U.S. EPA, 2004, 056905). Source-oriented analyses were also conducted to identify specific
source-types associated with mortality. These studies implicate PM2.5 from anthropogenic origin,
such as motor vehicle emissions, coal combustion, oil burning, and vegetative burning, as being
important in contributing to increased mortality (U.S. EPA, 2004, 056905).


6.5.2.   Associations of Mortality and Short-Term Exposure to PM

      The recent literature examines the association between short-term exposure to various PM size
fractions (i.e., PM10, PM10_2.5, PM25, UFPs, or species [e.g., OC, EC, transition metals, etc.]) and
mortality. This ISA, similar to previous AQCDs, focuses more heavily on multicity studies, and
especially those conducted in the U.S. and Canada (Table 6-15). By using this approach it is possible
to: (1) obtain a more representative sample of or insight into the PM-mortality relationship observed
across the U.S.; (2) analyze the association between mortality and short-term exposure to PM at or
near ambient conditions  observed in the U.S.; (3) examine the potential heterogeneity in effect
estimates between cities  and regions; and (4) analyze the confounders and/or effect modifiers that
may explain the PM-mortality relationship in the U.S. Although this section focuses on mortality
outcomes in response to  short-term exposure to PM, it does not evaluate studies that examine the
association between PM and infant mortality. These studies are evaluated in Section 7.5,,although it
is possible that short- and long-term in utero exposures may contribute to infant mortality. In
addition, the exposure windows of interest for this unique health outcome can be difficult to
characterize and may span both short- and long-term exposure periods.


Table 6-15.   Overview of U.S. and Canadian multicity PM studies of mortality analyzed in the 2004 PM
            AQCD and  the PM ISAb.
Study
Location
Mean Concentration 98th; 99th Upper Percentile:
(ug/m ) Percentiles (ug/m ) Concentrations (ug/m )
PM10
Dominici et al. (2003, 1564071'
Burnett and Goldberg (2003, 042798)3
Peng et al. (2005, 087463)
Dominici et al. (2007, 097361)'
Wfelty and Zeger (2005, 0874841 '
Bell et al. (2009, 1910071
Burnett et al. (2004, 0862471
Samoli et al. (2008, 1884551
Schwartz (2004, 0789981
Schwartz (2004, 0535061
Zeka et al. (2005, 088068)

Zeka et al. (2006, 088749)
90 U.S. cities
8 Canadian cities
100 U.S. cities
100 U.S. cities
100 U.S. cities
84 U.S. urban
communities
12 Canadian cities
12 Canadian cities
90 U.S. cities8
22 European cities
14 U.S. cities
14 U.S. cities
20 U.S. cities
20 U.S. cities
15.3-53.2
25.9
13-49
13-49
13-49
NR
NR
NR
23-36d
23-36d
15-37.5
15.9-37.5
NR

95th: 54; Maximum: 121
50th: 27.1; 75th:
Maximum: 48.7
50th: 27.1; 75th:
Maximum: 48.7
50th: 27.1; 75th:
Maximum: 48.7
NR
NR
NR
75th: 31 -57
75th: 31 -57
NR
NR
32.0
32.0
32.0







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               Study
,     ..          Mean Concentration       98th; 99th          Upper Percentile:
Locatlon               (ug/m3)          Percentiles (ug/m3)  Concentrations (ug/m3)
PM2.5
Burnett and Goldberg (2003, 042798)3
Dominici et al. (2007, 0973611
Zanobetti and Schwartz (2009, 1884621
Franklin et al. (2007, 091257)
Franklin et al. (2008, 097426)9
Ostro et al. (2006, 0879911
Ostro et al. (2007, 0913541
Burnett et al. (2004, 0862471
8 Canadian cities
96 U.S. cities
112 U.S. cities
27 U.S. cities
25 U.S. cities
9 California counties
6 California counties
12 Canadian cities
13.3 38.9; 45.4
NR
13.2 34.3; 38.6
15.6 45.8; 54.7
14.8 43.0; 50.9
19.9 68.2; 82.0
18.4 61.2; 70.1
12.8 38.0; 45.0
95th: 32; Maximum: 86
NR
Maximum: 57.4
Maximum: 239
Maximum: 239.2
95th: 61. 3; Maximum: 160.0
Maximum: 116.1
Maximum: 86.0
PM10-2.5
Burnett and Goldberg (2003, 04279813
Zanobetti and Schwartz (2009, 1884621
Burnett et al. (2004, 086247)
Villeneuve et al. (2003, 055051)
Klemmetal. (2004, 0565851
Slaughter etal. (2005,073854)
Wilson et al. (2007, 1571491
Kettunen et al. (2007, 0912421
Perez et al. (2008, 1560201
8 Canadian cities
47 U.S. cities
12 Canadian cities
Vancouver, Canada
Atlanta, Georgia
Spokane, Washington
Phoenix, Arizona
Helsinki, Finland
Barcelona, Spain
12.6
11.8 40.2; 47.2
11.4
6.1
9.7 20.7
NR
NR
Cold season: 6.7d
Warm season: 8.4d
Saharan Dust Days: 16.4
Non-Saharan Dust Days:
14.9
95th: 30; Maximum: 99
Maximum: 88.3
Maximum: 151
90th: 13.0; Maximum: 72.0
50th: 9.34; 75th: 11.94
Maximum: 25.17
NR
NR
Cold season: 50th: 6.7
75th: 12.5; Maximum: 101.4
Warm season: 50th: 8.4
75th: 11. 8; Maximum: 42.0
Saharan Dust Days
50th: 14.8; 75th: 21. 8
Maximum: 36.7
Non-Saharan Dust Days
50th: 12.6; 75th: 18.9
Maximum: 93.1
3 Multicity studies examined in the 2004 PM AQCD (U.S. EPA, 2004, 0
b Because only two multicity study was identified that examined PM10_2 5, single-city and international studies that examined PM10_2 5 were analyzed in this ISA and are included in this table.
cThe majority of multicity studies examined in the PM ISA provide the mean PM concentration of each individual city, not an overall PM concentration across all cities. As a result, the range of PM
concentrations for a particular study are presented, which represents the lowest and highest mean PM concentrations reported across cities, if an overall mean is not provided within the study.
a Median PM concentration.
eThe study included 90 U.S. cities in the 1-day lag analysis, but only 15 U.S. cities in the analysis of the average of lag days 0-1.
f The concentrations reported for these studies were estimated from Peng et al. (2005, 087463) because they used the same number of cities and years of data from NMMAPS.
9 This study did not present an overall mean 24-h avg PM2 5 concentration across all cities for each season. The range of mean 24-h avg concentrations reported in this table for each season represents the
lowest mean 24-h avg PM2 5 concentration and the highest 24-h avg PM2 5 concentration reported across all cities included in the study.
6.5.2.1.   PM10
        The majority of studies that examined the association between short-term exposure to PM and
mortality focused on effects attributed to PMi0.  Although these studies do not characterize the
compositional differences in PMi0 across the cities examined in each of the studies evaluated, they
can provide an underlying basis for the overall pattern of associations observed when examining the
relationship between PMi0_2.5 and PM2.5  and mortality. The studies evaluated  in this review analyzed
the PMio-mortality relationship through either a time-series or case-crossover design.1
1 Schwartz (1981, 078988) used a case-crossover study design, but also conducted a time-series analysis to validate the results obtained
 using the case-crossover approach.
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      Time-Series Analyses

      Mortality associations with short-term exposure to PMi0 in the U.S. have been examined in
several updated time-series analyses of the NMMAPS. In the previous NMMAPS analysis
(Dominici  et al., 2003, 156407: Samet et al., 2000, 005809; Samet et al., 2000, 010269) of the
1987-1994 data, which was reviewed in the 2004 PM AQCD (U.S. EPA, 2004, 056905). the
strongest association was found for nonaccidental mortality for 1-day lag, with a combined estimate
across 90 cities of 0.21% (95% PI: 0.09-0.33) per 10 ug/m  increase in PMi0. The association was
found to be robust to the inclusion of other gaseous copollutants in the regression models, but the
investigators found heterogeneity across regions, with the strongest associations in northeastern
cities. In the new updated analyses, the investigators examined additional issues surrounding the
association between PM and mortality including: seasonal effect modification; change in risk
estimates over time; sensitivity of results to alternative weather models; and effect modification by
air conditioning use. The NMMAPS data has also been used to examine the PM concentration-
response relationship using PMi0 data from 20 cities (Section 6.5.2.7). A few multicity studies
conducted in Canada and Europe provide additional information, which further clarifies and supports
the association between PM and mortality presented in the NMMAPS analyses.

      Seasonal Analyses of PM10-Mortality Associations

      Using the updated NMMAPS data, which consisted of 100 U.S. cities for the period
1987-2000, Peng et al. (2005, 087463) examined the effect of season on PMi0-mortality associations.
In their first stage regression model, for each city, the PMi0 effect was modeled to have a sinusoidal
shape that completes a cycle in a year, but was constrained to be periodic across years using
sine/cosine terms. The authors also considered a model that consisted of PMio-season interactions
using season indicators. Both of these models also included covariates that were used in their earlier
NMMAPS analyses. In the second stage model, the seasonal patterns of PMi0 mortality  coefficients
were  estimated for seven geographic regions and on average for the entire U.S. Peng et al. (2005,
087463) found for 1-day lag, at the national level, season specific increases in nonaccidental
mortality per 10 (ig/m3  increase in PM10 of: 0.15% (95% PI: -0.08 to  0.39), 0.14% (95% PI: -0.14 to
0.42), 0.36% (95% PI: 0.11-0.61), and 0.14% (95% PI: -0.06 to 0.34) for winter, spring, summer, and
fall, respectively. The corresponding all-season estimate was 0.19% (95% PI: 0.10-0.28). After the
inclusion of SO2, OB, or NO2 in the model with PMi0 in a subset of cities (i.e., 45 cities)  for which
data existed, PMi0 risk  estimates remained fairly robust. An analysis by geographic region found a
strong seasonal pattern in the Northeast. Figure 6-16 presents the estimated seasonal pattern of PMi0
risk estimates by region from Peng et al. (2005, 087463). which includes a sensitivity analysis aimed
to determine the appropriate number of degrees of freedom for temporal adjustment. It is clear from
Figure 6-16 that the Northeast has the strongest association with PMi0 and mortality, which peaks in
the summer and is robust to the extent of temporal adjustment. The industrial Midwest also shows
the summer peak, but with smaller risk estimates. Other regions have either no seasonal pattern
(Southeast) or a suggestion of a spring peak that appears to be sensitive to the extent of temporal
adjustment. On a nationwide basis, the PMi0 risk estimates appear to  peak between spring and
summer. Overall, this study identified an effect modifier that may be  useful in identifying the
specific chemical  component(s) of PM that are related to specific regions and times of the year.

      Change in PM10-Mortality Associations over Time

      Dominici et al. (2007, 097361) conducted an analysis of the extended NMMAPS  data set (i.e.,
1987-2000) to examine if short-term PMi0-mortality risk estimates changed during the course of the
study period. The investigators estimated the average PMi0 mortality risk coefficient for 1-day lag,
using essentially the same model specification as in their 2003 analysis, separately for three time
periods (i.e., 1987-1994, 1995-2000, and 1987-2000) the "eastern U.S." (62 counties), the "western
U.S." (38  counties), and all 100 U.S.  counties. To produce national and regional estimates, two-stage
hierarchical models were used as in the previous NMMAPS studies. As shown in Table  6-16, the
authors found a continuation of the PMi0-mortality association in the nationwide data for the entire
study period. A comparison of the relative risk estimates for 1987-1994 vs. 1995-2000 suggests weak
evidence (not a statistically significant difference) that  short-term effects declined. Most of the
decline in the national estimate appears to be attributable to the eastern U.S. counties. However, the
decline in the risk estimate for all-cause mortality in the eastern U.S.  appears to be
December 2009                                 6-161

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disproportionately influenced by the reduction in the risk estimate for the "other" mortality category
(i.e., all-cause minus cardio-respiratory category, which may be 40-50% of all-cause deaths in U.S.
cities). Likewise, the apparent increase in the risk estimate for all-cause mortality in the western U.S.
appears to be affected by the increase in the risk estimate for the "other" mortality category. Because
the study does not clearly identify the specific  cause(s) in the "other" mortality category that are
affected by PM, interpreting the reduction in risk estimates for all-cause mortality requires caution.
In contrast, the apparent reductions (-23%) in  PMi0 risk estimates for cardio-respiratory deaths were
more comparable between the two regions.
           Industrial Midwest
  c  1-5-
  
  c
               Southeast
1.0-

0-5	

0.0 —
          i     i     i
         100  200  300
                              Northeast
                              Southwest
                                                      Northwest
                                  100  200  300
                                             Day in year
                                                       i     i    i
                                                     100  200  300
Southern California

    i     i     r
   100  200  300
                                            Source: Reprinted with Permission of Oxford University Press from Peng et al. (2005, 0874631

Figure 6-16.    National and regional estimates of smooth seasonal effects for PM10 at a 1-day
               lag and their sensitivity to the degrees of freedom assigned to the smooth
               function of time in the updated NMMAPS data 1987-2000.  Note: The degrees of
               freedom chosen were 3 df (short-dashed line), 5 df (dotted line), 7 df (solid line), 9
               df (dotted-and-dashed line), and 11 df (long-dashed line) per year of data.

      In addition, the investigators estimated time-varying PMi0 mortality risk as a linear function of
calendar time for the period 1987-2000, producing the percentage rate change in the PM10 risk
estimate with a change in time of 1 yr. The estimated rate of decline in slope for all-cause mortality
and the combination of cardiovascular and respiratory mortality were -0.012 (95% PI: -0.037 to
0.014) and -0.016 (95% PI: -0.058 to 0.027), respectively. The authors also estimated a PM2.5
mortality risk for the period 1999-2000 (discussed in Section 6.5.2.2.).
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Table 6-16.   NMMAPS national and regional percentage increase in all-cause, cardio-respiratory, and
             other-cause mortality associated with a 10 ug/m3 increase in PMio at lag 1 day for the
             periods 1987-1994,1995-2000, and 1987-2000.
                   1987-1994
95% PI
1996-2000
95% PI
1987-2000
95% PI
ALL CAUSE
East
West
National
0.29
0.12
0.21
0.12, 0.46
-0.07, 0.30
0.10, 0.32
0.13
0.18
0.18
-0.19, 0.44
-0.07, 0.44
0.00, 0.35
0.25
0.12
0.19
0.11,0.39
-0.02, 026
0.10,0.28
CARDIORESPIRATORY
East
West
National
0.39
0.17
0.28
0.16, 0.63
-0.07, 0.40
0.14, 0.43
0.30
0.13
0.21
-0.13, 0.73
-0.23, 0.50
-0.03, 0.44
0.34
0.14
0.24
0.15,0.54
-0.05, 0.33
0.13, 0.36
OTHER
East
West
National
0.21
0.09
0.15
-0.03, 0.44
-0.21,0.38
-0.02, 0.32
0.00
0.23
0.17
-0.49, 0.50
-0.15, 0.62
-0.07, 0.41
0.15
0.11
0.15
-0.09, 0.39
-0.10, 0.33
0.00, 0.29
                                                     Source: Reprinted with Permission of HEI from Dominici et al. (2007, 097361)


      The objective of the Dominici et al. (2007, 097361) study described above was motivated by
accountability research, the idea of measuring the impact of policy interventions. However, unlike
the intervention studies conducted in Hong Kong (Hedley et al., 2002, 040284) and Dublin, Ireland
(Clancy et al., 2002, 035270) that were reviewed in the 2004 PM AQCD (U.S. EPA, 2004, 056905).
this study was not designed to estimate a reduction in mortality in response to a sudden change in air
pollution. In fact, the figure of observed trend in PMio levels presented in the Dominici et al. (2007,
097361) study indicates that the decline in PMio levels during the study period was very gradual,
with much of the decline appearing in the first few years (median values of ~33 (ig/m3  in 1987 to
~25 (ig/m3 in 1992, then down to ~23 (ig/m3 in 2000). A flaw in the use of the time-series study
design for this type of analysis is that it adjusts for long-term trends, and, therefore, does not
estimate the change in mortality in response to the gradual change in PM10. The apparent change,
though weak, in the PMio risk estimates may also reflect a potential change in the composition of
PMio (i.e., PMio_2.5 or PM2.5). The study listed a number of PMio-related air pollution control
programs that were implemented between 1987 and 2000. Some of these programs, such as the Acid
Rain Control Program, did result in major reductions in emissions, and, therefore, could have
contributed to the results observed, but the analytic approach used in the study does not allow for  a
systematic analysis of the effect of air pollution policies on the risk of mortality.

      Sensitivity of PM-Mortality Associations to Alternative Weather Models

      To examine the sensitivity of PM10-mortality risk estimates to alternative weather models that
consider longer lags, Welty and Zeger (2005, 087484) analyzed the updated NMMAPS 100 U.S.
cities data. All of the previous NMMAPS analyses only considered temperature and dew point up to
3-day lags.  In this analysis, the authors considered various forms of a constrained distributed lag
model: (1) containing a step function of temperature with steps at lag 0, 2, 7 and extended to
14 days; (2) similar to (1) but with time-varying coefficients to change over season and study period;
and, (3) containing a smooth function to account for non-linearity in the temperature-mortality
relationship. With the combination of degrees of freedom for temporal trends and the number of
distributed lags, more than 20 models were applied to each of the 3 lag days (0, 1, and 2) of PMi0.
These city-specific risk estimates were then combined across the 100 cities in the second stage
Bayesian model. The combined PMio risk estimates were generally consistent within the lag. In
particular, the risk  estimates for nonaccidental mortality for lag  1 day ranged between 0.15% and
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0.25% per 10 (ig/m3 increase in PM10, and were always statistically significant regardless of the
model used. In addition, the range of these point estimates across the models was found to be much
narrower than the regression posterior intervals. Thus, the PMi0 risk estimates at lag 1 day were
robust to alternative temperature models that considered temperature effects lasting up to a 2-week
period.
      In summary, the above three analyses of the updated NMMAPS data provided useful
information on PM-mortality risks, resulting in the following conclusions: (1) estimated PMi0
mortality risk is particularly high in the northeast and in the summer; (2) there remains an overall
PMio-mortality association in the 1987-2000 time period as  well as the 1995-2000 time period; (3)
there is a weak indication that PMio-mortality risk estimates are declining; and (4) PMio-mortality
risk estimates were not sensitive to alternative temperature models.

      Effect Modification of PM10-Mortality Associations by Air Conditioning Use

      It has been hypothesized that air conditioning (AC) use reduces an individual's  exposure to
PM and subsequently modifies the PM-mortality association. Bell et al.  (2009, 191007) investigated
the role of AC use on the relationship between PMi0 and all-cause mortality using the  NMMAPS
PMio risk estimates from 84 U.S. urban communities from 1987-2000.1  Bayesian hierarchical
modeling was used to examine if AC prevalence (i.e., fraction of households with central or any AC)
explained city-to-city variation in PMi0 risk estimates. The authors calculated yearly, summer-only,
and winter-only effect estimates  stratified by housing stock that had either central AC  or any AC,
which includes window units. Risk estimates for lag 1 (previous day) were used in the analysis
because this lag showed the strongest association with mortality in the original NMMAPS analyses.
Community-specific AC prevalence was calculated from national survey U.S. Census  American
Housing Survey (AHS) data, which is available every two years. The investigators computed percent
change in PMi0 effect estimates per an additional 20% of the population acquiring AC.
      The AC variables were not strongly correlated with socio-economic variables (poverty rate,
unemployment, and education) from the U.S.  Census (correlation ranged from -0.27 to 0.29). Bell
et al. (2009, 191007) found that communities with higher AC prevalence had lower PMi0 mortality
risk estimates for all-cause mortality (-30.4% [95% PI: -80.4 to 19.6] per an additional 20% of the
population acquiring any AC; -39.0%  [95% PI: -81.4 to 3.3] for central AC), but results were not
statistically significant. When restricting the analysis to the summer months and focusing on the 45
cities with summer-peaking PMi0 concentrations, the authors reported positive, non-significant risk
estimates  (29.9% [95% PI: -84.0 to 144] per an additional 20% of the population acquiring any AC; -
2.0% [95% PI: -60.3 to 64.3] for central AC). A similar analysis was conducted for winter months
using data from six cities with winter peaking PMio concentrations, but  the confidence bands were
too wide (due to the small sample size) for meaningful interpretation.
      Although the estimated reductions in PMio all-cause mortality risks from AC use reported in
the Bell et al. (2009,  191007) study were not statistically significant, their large magnitude suggests
that AC use may reduce an individual's exposure to PM. Given the expected additional increase in
AC use in the future, and the results from recent multicity studies, which have reported stronger PM-
mortality associations during the warm season, AC use may play a larger role in determining an
individuals exposure to PM. Studies that have examined the effect of AC use on the PM2 5-mortality
association have reported similar results. For example, Franklin et al. (2007, 091257)  (discussed in
detail in Section 6.5.2.2) found that AC use non-significantly modified PM2.5 mortality risk
estimates, but the result was suggestive of higher PM2.5 effects in cities with lower AC use,
especially in cities with summer-peaking PM2.5 concentrations. Overall, further investigation is
needed to fully understand the relationship between AC use and mortality attributed to short-term
exposure to PM.

      PM10-Mortality Associations in Canada and Europe

      Burnett et al. (2004, 086247) examined the association between mortality and various air
pollutants in 12 Canadian cities,  and reported that the most consistent association was  found for
NO2. For this analysis, PM was measured every 6th day for the majority  of the study period, and the
PMio concentrations  used in the study represent the sum of the PM25 and PMi0_2.5, which were
directly measured by dichotomous  samplers. The authors found that the simultaneous  inclusion of
1 This study also examined risk estimates for cardiovascular and respiratory hospital admissions in older adults (> 65).
December 2009                                  6-164

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NO2 and PM10 in a model, on those days with PM data, greatly reduced the PM10 association with
nonaccidental mortality, from 0.47% (95% CI: 0.04-0.89) to 0.07% (95% CI: -0.44 to 0.58) per
10 (ig/m3 increase. The previous Canadian multicity analysis (Burnett and Goldberg, 2003, 042798).
a re-analysis of Burnett et al. (2000, 010273) reviewed in the 2004 PM AQCD (U.S. EPA, 2004,
056905). did not consider gaseous pollutants. Thus, PMi0 risk estimates in the Canadian data appear
to be more sensitive to NO2 than those estimates reported in U.S. studies.
      The association between PM10 and mortality in Europe was also reviewed in the 2004 PM
AQCD (U.S. EPA, 2004, 056905) through Katsouyanni et al. (2003, 042807). which presented
results from the APHEA-2 study, a multicity study that examined PMi0 effects on total mortality in
29 European cities. Analitis et al. (2006, 088177) published a brief report on effect estimates  for
cardiovascular and respiratory deaths also based on the 29 European cities, within the APHEA2
study. They reported for the average of 0-  and 1-day lags, PMi0 risk estimates per 10 (ig/m3 of 0.76%
(95% CI: 0.47-1.05) for cardiovascular deaths and 0.71% (95% CI: 0.22-1.20) for respiratory deaths
in random effects models.

      Comparison of PM-Mortality Associations in Europe, Canada, and the U.S.

      The APHENA study (Samoli et al., 2008, 188455) was a collaborative effort by the APHEA,
NMMAPS, and the Canadian multicity study investigators to evaluate the coherence of PMi0
mortality risk estimates across locations and possible effect modifiers of the PM-mortality
relationship using a common protocol. To  adjust for temporal trends,  Samoli et al. (2008, 188455)
used 3, 8, and 12 degrees of freedom (df) with natural splines and penalized splines, as well as the
minimization of the sum of the absolute values of the partial auto-correlation function (PACF). The
investigators also included a smooth function of temperature on the same day of death and the day
before death. The study reported risk estimates for a 1-day lag (from all three data sets), the average
of lag day 0 and 1 (all but for the Canadian data because PM data was collected every 6th day), and
an unconstrained distributed lag model using lags of 0, 1, and 2 days  (all but for the Canadian data).
The second-stage regression included: (a)  the average pollution level and mix in each city; (b) air
pollution exposure characterization (e.g., number of monitors, density of monitors); (c) the health
status of the population (e.g., cardio-respiratory deaths as a percentage of total mortality, crude
mortality rate, etc.); and (d) climatic conditions (e.g., mean and variance of temperature). In addition,
unemployment rate was examined for 14 European cities and all  U.S. cities. Effect modification
patterns were examined only for cities with complete time-series data and using the average of lags 0
and 1 day, resulting in the exclusion of the Canadian data.
      Generally, the risk estimates from Europe and the U.S. were similar, but those from Canada
were substantially higher.1 For example, the percent excess risks  per 10 ug/m3 increase in PMi0 for
all ages using 8 df/yr and penalized splines were 0.84% (95% CI: 0.30-1.40), 0.33% (95%  CI: 0.22-
0.44), and 0.29% (95% CI: 0.18-0.40) for  the Canadian, European, and U.S. data, respectively. Note
that the risk estimate for the 90  U.S. cities is slightly larger than that reported in the original
NMMAPS study (0.21%, using natural splines, and more temperature variables). In the all ages
model, the average of lag days 0 and 1, and the distributed lag model with lags 0, 1, and 2 did not
result in larger risk estimates compared to those for a 1 day lag. In copollutant models, PMi0  risk
estimates did not change when controlling for O3. Figure 6-17 shows the risk estimates from  the
three data sets for alternative extent of temporal smoothing and smoothing methods. The Canadian
data appear less  sensitive to the extent of temporal smoothing or  smoothing methods (Panel A of
Figure 6-17). When stratifying by age the  risk estimates for the older age group (> 75 yr) were
consistently larger than those for the younger age group (<75 yr) (e.g., 0.47% vs. 0.12% for the U.S.
data) for all the three data sets. Although the study did not quantitatively present the results from the
effect modification analyses, some evidence of effect modification across the study regions was
observed. The investigators reported that,  in the European data, higher levels of NO2 and a larger
NO2/PMio ratio were associated with greater PMi0 risk estimates, and that while this pattern was also
present in the U.S. data, it was less pronounced. Additionally, in the U.S.  data, smaller PM10 risk
estimates were observed among older adults in cities with higher O3 levels. Effect modification by
temperature was also observed, but only in the European data.
1 The risk estimate reported for the 12 Canadian cities examined in the APHENA study is higher than that reported by Burnett et al. (2004,
 086247). This is because the APHENA study did not use the 12 cities data from Burnett et al. (2004, 086247). but instead used a
 composite of the data from three previous studies conducted by the same group by the same group (Burnett and Goldberg, 2003,
 042798; 1998, 029505; Burnett etal., 2000, 010273).
December 2009                                  6-165

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  5fl
  ee
  Oi
  'Z  i.o
  c
  !B
  g  0.5
  Q_
      0.0
     -0.5
                                        • PS
                                        ANS
  3 8 12
Canada (n= 12)
 3  8 12
Europe (n = 22)

  df/year
                                   3 8 12
                                  USA(n = 90)
                                                    2-5
                           CO
                           2  1.5
                           u

                           'Z  i-O
                           Ł
                                                    0,0
                                                   -0.5
3  8  12PACF
Europe (n = 22)
3 8 12PACF
USA(n=15)
i   i  i  i
3   8 12PACF
Europe-USA
                                                                       df/year

                                                                          Source: Samoli et al. (2008, 188455)
Figure 6-17.    Percent increase in the daily number of deaths, for all ages, associated with a
               10-ug/m3 increase in PMi0: lag 1 (A) and lags 0 and 1 (B) for all three centers.
               PACF indicates df based on minimization of PACF.

      In this study, the underlying basis for the larger PMi0 risk estimates (by twofold) in the
Canadian data compared to the European and U.S. data could not be identified, even when consistent
statistical methods were applied across each of the data sets. Because the effect modification of PMi0
risk estimates were not examined in the Canadian data, the potential influence of air pollution type or
mixture could not be ruled out as a potential source of heterogeneity across the three data sets. It
should be noted that both the original U.S. and European studies reported regional heterogeneity in
PM risk estimates, and the U.S. data also demonstrated seasonal heterogeneity. In both of these cases
the specific characteristics associated with the regions that contributed to the heterogeneity observed
were not identified. Thus, further investigation is needed to identify  factors that influence the
heterogeneity in PM risk estimates observed between different countries and across regions.


      Case-Crossover Analyses

      Since the 2004 PM AQCD (U.S. EPA, 2004, 056905) investigators have used the
case-crossover study design more frequently as an alternative to time-series analyses to examine the
association between short-term exposure to PM and mortality. This study design allows for the
control of seasonal variation, time trends, and slow time varying confounders without the use of
complex models. However, similar to  any study design, biases can be introduced into the study
depending on the control (i.e.,  referent) period selected (Janes et al., 2005, 087535). The multicity
case-crossover analyses discussed below match cases (i.e., days in which a death occurred) to
controls (i.e., days in which a death did not occur), to control for (1) seasonal patterns and gaseous
pollutants;  or (2) temperature.  In addition, the studies attempted to examine the heterogeneity of
effect estimates through the analysis of individual-level and city-specific effect modification.

      Controlling for Temperature

      Schwartz (2004, 078998) investigated the PMi0-mortality association in 14 U.S.  cities for the
years 1986-1993 (some cities started in later years because of PMi0 data availability) using a
case-crossover study design. Note that in this  analysis, four more cities (Boulder, CO; Cincinnati,
OH; Columbus, OH; and Provo-Orem, UT) were added to the cities  Schwartz (2003, 042800)
previously  analyzed using a time-series study design. These cities were chosen for this analysis
because they collected daily PMi0  data, unlike most  U.S. cities, which only monitor PMi0 every six
days. Lag 1-day PMi0 risk estimates were computed using several methods. Model 1 (i.e., the main
model) and Model 2 were constructed from a case-crossover analysis with bidirectional control days
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(7-15 days before and after the case). Model 1 obtained city-specific estimates in the first stage
analysis, followed by a second stage random-effects model to obtain a combined estimate. Model 2
is the same as Model 1, but consisted of a single stage model, which included data from all 14 cities.
Models 3 and 4 were also constructed from a case-crossover analysis, but used time-stratified control
days (i.e., matched on season and temperature within the same degree in Celsius). Model  3 obtained
single-city estimates in the first stage analysis, followed by a second stage random-effects model to
obtain combined estimates. Model 4 used the same approach as Model 3, but consisted of a single
stage model including data from all 14 cities. The final model, Model 5 consisted of a two-stage
Poisson time-series model, which produced city-specific estimates in the first stage, and combined
estimates across cities in the  second stage. In the main model the estimated excess risk for
nonaccidental mortality was  0.36% (95% CI: 0.22-0.50) per  10 (ig/m3 increase in PMi0. The other
models yielded a similar magnitude of effect estimates, ranging from 0.32% (Model 2) to 0.53%
(Model 4). Thus, the methods used to select control days and adjust for weather in the case-crossover
design did not result in major differences in effect estimates, and in addition, were comparable to the
estimates obtained from the time-series analysis, 0.40% (Model 5).

      Controlling for Gaseous Pollutants

      In a subsequent analysis, Schwartz (2004, 053506) analyzed the same 14 cities data described
above, using a case-crossover design, to investigate the potential  confounding effects of gaseous
pollutants. For each case day, control days were selected from all other days of the same month of
the same year. In addition, control days were selected if they had gaseous pollutant concentrations
within: 1 ppb, 1 ppb, 2 ppb, or 0.03 ppm for SO2, NO2, 1-h max O3, and CO, respectively, of the case
day.  Unlike the study described above (Schwartz, 2004, 078998)  in this analysis, the excess risk was
estimated for the average of 0- and 1-day lag PMi0 (rather than 1-day lag). In addition, apparent
temperature (a composite index of temperature and humidity) was used rather than temperature and
humidity individually. The case-crossover analysis was conducted in each city, and a combined
estimate was computed in a second-stage random effects model. The number of cities  analyzed
varied across pollutants depending on the availability of monitors. The study reported  PMi0 risk
estimates for nonaccidental mortality of 0.81% (95% CI: 0.47-1.15), 0.78% (95% CI:  0.42-1.15),
0.45% (95% CI: 0.12-0.78), and 0.53% (95% CI: 0.04-1.02)  per 10 (ig/m3 increase, for the analysis
matched by  SO2 (10 cities), NO2 (8 cities), O3 (13 cities), and CO (13 cities), respectively.
      Schwartz (2004, 053506) only presented PMi0 risk estimates matched by gaseous pollutants,
therefore, it  is unclear in this analysis how matching by gaseous pollutants affected (i.e., reduced or
increased) unmatched PMi0 risk estimates. The estimates reported were computed using the average
of 0- and 1-day lagged PMi0  and, therefore, cannot be directly compared to the 1-day lag  PMi0 risk
estimates obtained in the Schwartz  (2004, 078998) 14-city study  described above. The estimates
reported in the case-crossover analysis that controlled for gaseous pollutants (Schwartz, 2004,
053506) are generally larger  than those obtained in the analysis that controlled for temperature
(Schwartz, 2004, 078998). which was expected since the Schwartz (2004, 053506) analysis used
2-day avg PMi0. However, the estimates reported in Schwartz (2004, 053506) are comparable to the
average of 0- and 1-day lagged PMi0 risk estimate for nonaccidental mortality (0.55% [95% CI:
0.39-0.70]) per 10 (ig/m3 increase from the 10-city study (Schwartz, 2003, 042800). which was
reviewed in  the 2004 PM AQCD (U.S. EPA, 2004, 056905).  Overall, Schwartz (2004, 053506)
provided an alternative method to assess the influence of gaseous copollutants. The results suggest
that PMio is  significantly associated with all-cause mortality  after controlling for each of the gaseous
copollutants.

      City-Level Effect Modification

      Zeka et al. (2005, 088068) expanded the 14 cities analyses  conducted by Schwartz  (2004,
078998: 2004, 053506) to 20 cities, added more years of data (1989-2000), and investigated PM10
effects on total and cause-specific mortality using a case-crossover design. Individual  0-,  1-, and
2-day lags as well as an unconstrained  distributed lag model  with 0, 1, and 2 lag days were
examined. For each case day, control days were defined as every  third day in the same month of the
same year, to eliminate serial correlation. The authors also investigated potential effect modifiers in
the second stage regression using city-specific variables including percent using AC, population
density, standardized mortality rates, the proportion of elderly in  each city, daily minimum apparent
December 2009                                 6-167

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temperature in summer, daily maximum apparent temperature in winter, and the estimated
percentage of primary PMi0 from traffic sources.
              o
              0>
                 0,8
             I °4
             -P
              o  °-4
              Ł
             •E  0.2
              o
                -0.2
                -0.4
1000 3000
(count/mile  )
                                      25%  75%
               25%  75%     25%  75%
                       Population
                         density
Variance of
summer AT
                                Mean of
                                winter AT
% Primary
PMIO from
  traffic
                                         City effect modifiers
                                                   Source: Reprinted with Permssion of BMJ Group from Zeka et al. (2005, 088068)

Figure 6-18.    Effect modification by city characteristics in 20 U.S. cities. Note: The two
               estimates and their Cl for each of the modifying factors represent the percentage
               increase in mortality for a 10 ug/m3 increase in PMio, for the 25th percentile, and
               75th percentile of the modifier distribution across the 20 cities.

      The investigators found that, for all-cause (nonaccidental) mortality, lag 1 day showed the
largest risk estimate (0.35% [95% CI: 0.21-0.49] per 10 (ig/m3) among the individual lags.
Respiratory mortality exhibited associations at lag 0, 1, and 2 days  (0.34%, 0.52%, and 0.51%,
respectively), whereas cardiovascular mortality was most strongly associated with PMi0 at lag day 2
(0.37%). The sum of the distributed lag risk estimates (e.g., 0.45%  [95% CI: 0.25-0.65] for all-cause
mortality) was generally larger than those for single-day lag estimates. The excess risk estimates for
single-day lags for specific respiratory and cardiovascular causes had generally wider confidence
intervals due to their smaller daily mortality counts, but some of the categories showed markedly
larger estimates when included in the combined distributed lag model (e.g., pneumonia 1.24% [95%
CI: 0.46-2.02]). As  shown in Figure 6-18, Zeka et al. (2005, 088068) also found evidence indicative
of several PM10 effect modifiers including higher population density and the estimated percentage of
primary PMio from traffic. When 25th versus 75th percentiles of these city-specific  variables were
evaluated, the estimated percent increase in mortality attributed to PMio appears to contrast
substantially (e.g., 0.09% vs. 0.52% for variance of summer time apparent temperature).
      The effect modifiers investigated by Zeka et al. (2005, 088068) consisted of city-specific
variables. Some of these variables are ecological in nature, and therefore, interpreting the meaning of
"effect modification" requires some caution. As the investigators pointed out, the population density
and the estimated percentage of primary PMio from traffic were correlated in this data set (r = 0.65)1.
These variables may also be a surrogate for another or composite aspects of "urban" characteristics.
1 The correlation coefficient was calculated based on the numbers provided in Table 1 of Zeka et al. (2005,
December 2009
       6-168

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Thus, the apparent effect modification by traffic-related PM10 needs further investigation.
Interestingly, the percent of homes with central AC was not a significant effect modifier of PMi0 risk
estimates, which questions the impact of reduced building ventilation rates on PM exposure. Overall,
this study presented PMi0 risk estimates that are consistent with those found in other analyses, but
also provided new information on the risk estimated for broad and specific respiratory and
cardiovascular mortality designations, along with possible effect modifying city-specific
characteristics.

      Individual-level Effect Modification

      In an additional analysis, Zeka et al. (2006, 088749) examined individual-level, instead of
city-specific, effect modification of PMi0-mortality associations in the 20 U.S. cities described above
using the same case-crossover design. City-specific estimates were obtained in the first stage model,
followed by a second stage model which estimated the overall effects across all cities. Figure 6-19
shows PMio excess risks by four of the individual characteristics examined in the study (i.e., gender,
race, age group, and education). It should be noted that the lag and averaging of days for the
associations reported varied across the  outcomes: all-cause and heart disease deaths used the average
of lag 1 and 2 days; respiratory deaths used the average of lag 0 through 2 days; MI deaths used lag
0 day; and stroke deaths used lag 1 day. PMi0 risk estimates do not appear to differ by gender or by
race. However, significant differences were found for the youngest vs. oldest age groups for
all-cause and heart disease mortality. For all-cause mortality, the level of education appeared to be
inversely related to the PMi0 risk estimates (i.e., greater risk for lower education level), but this
observation was not statistically significant. The study also examined effect modification by location
of death ("out-of-hospital" versus "in-hospital") and season (Figure 6-20). The "out-of-hospital"
deaths showed larger PMi0 risk estimates than were found for "in-hospital deaths" with a significant
difference per 10 ug/m3 for all-cause (0.71% versus 0.22%) and heart disease (0.93% versus 0.15%)
deaths. Stroke deaths also showed a significant difference (0.87% vs. 0.06%, not shown in Figure
6-20).
December 2009                                  6-169

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                               Gender
                 tn
                 d
                                      Male  ,
                                      Female
                                                                 Race
                          0 White
                          • Black
                                 0)
                                 tr
                             Age group
                                  1° <6b
                                  \& 6b-/b
                      0)
                      CC


                  Education
                                Ł•
                                a
                                                  in
                                                  9
                       0 Low
                         Medium
                         High
                                cc
                                                                 cc
Figure 6-19.   Percent excess risk in mortality (all-cause [nonaccidental] and cause-specific)
              per 10 ug/m3increase in PMioby individual-level characteristics.  The risk
              estimates and 95% confidence intervals were plotted using numerical results
              from tables in Zeka et al. (2006, 088749). The estimates with * next to them are
              significantly higher than the lowest estimate in the group.
December 2009
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                         Location of death
                    Season
                               0 In-hospital
                                 Out-of-hospitall
           ac
           111
              in
              CD
   o
   ><
   LU
                                                  in
                                                  CD
      in
      CD
                                                          f
                           Winter
                           Summer
                           Spring/Fall

                               31
                               cc
                                         so
                                         oj
                                         I
                       2        -L
                       'EL
                       :/3

                       Q~
Figure 6-20.   Percent excess risk in mortality (all-cause [nonaccidental] and cause-specific)
              per 10 ug/m3increase in PMi0 by location of death and by season.  The risk
              estimates and 95% confidence intervals were plotted using numerical results
              from tables in Zeka et al. (2006, 088749). The estimates with * next to them are
              significantly higher than the lowest estimate in the group.

      Overall, Zeka et al. (2006, 088749) showed a consistent pattern of effect modification by
contributing causes of death (i.e., pneumonia, stroke, heart failure, and diabetes) on PMi0 risk
estimates for primary causes of death (Figure 6-21; not all results for contributing cause are shown).
However, because the contributing causes of death counts were relatively small, as reflected by the
wide confidence intervals in Figure 6-21, most of the differences observed did not achieve statistical
significance.
December 2009
6-171

-------
5
.fr 4
1
o 3-
E
,E
a 2 -
U)
i
8 1-
o
* n
i °
s
„» .1-







K h


4
>






> 1
1






l>
^








4
1*



*
4
1
	 I 	



>



     "2 *
                           //
                                     //   /,
                                                            4?
          All cause
                                                              Ml
Stroke
Figure 6-21.
Respiratory

  Primary cause of death
        Source: Adatped with Permission of Oxford University Press from Zeka et al. (2006, 088749)
              Percent increase in mortality (all-cause [nonaccidental] and cause-specific) per
              10 ug/m3 increase in PMi0 by contributing causes of death.  The estimates with *
              (added to the original figure) indicates a significant difference.
      In addition, when examining the other effect modifiers, the results that show no difference in
     risk estimates between gender or race for all-cause and cardiovascular deaths are important,
given the relatively narrow confidence bands of these estimates. The effect modification by the
location of death has been reported previously in smaller studies, but the large contrast found for
all-cause and cardiovascular mortality in this large multicity analysis is noteworthy. The elevated
PMio risks reported by Zeka et al. (2006, 088749) for all-cause, heart disease (and stroke)
"out-of-hospital" deaths are also consistent with the hypothesis of acute PMio effects on "sudden
deaths" brought on by systemic inflammation or dysregulation of the ANS. The finding regarding the
seasonal effect modification, though significant only for respiratory deaths, is somewhat in contrast
with the Peng et al. (2005, 087463) analysis of the extended NMMAPS data, which observed the
greatest effects during the summer season. The apparent inconsistency may be due to the difference
in geographic coverage (i.e., 20 versus 100 cities) or methodology (i.e., case-crossover with referent
days in the same month of the same year vs. time-series analysis with adjustment for temporal trend
in the regression model).
      Summary of PM10 Risk Estimates

      Overall, the recent studies continue to show an association between short-term exposure to PM
and mortality. Although these studies do not examine mortality effects attributed to PM size fractions
that compose PMio, the regional, seasonal, and effect modification analyses conducted contribute to
the evidence for the PM2.5 and PM10_2.5 associations presented in Sections 6.5.2.2and 6.5.2.3,
respectively. Of the PMio studies evaluated, depending on the lag/averaging time and the number of
cities included, the estimates for all-cause (nonaccidental) mortality for all ages ranged from 0.12%
(Dominici  et al., 2007, 097361) to 0.84% (Samoli et al., 2008, 188455) per 10 (ig/m3  increase in
PMio, regardless of the study design used (i.e., time-series vs. case crossover). Although this range of
PM mortality risk estimates is smaller than those reported for PMi0_2.5 and PM2.5they do support the
December 2009
                                            6-172

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association between PM and mortality. The majority of studies examined present estimates for either
a lag of 1 day or a 2-day avg (lag 0-1), both of which have been found to be strongly associated with
the risk of death (Schwartz, 2004, 078998; 2004, 053506). The use of a distributed lag model (using
lag 0, 1, and 2 days) was found to result in slightly larger (by -30%) estimates compared to those for
single-day lags in the 20 cities study (Zeka et al., 2005, 088068). but when using the 15 cities data
from NMMAPS analyzed in the APHENA study (Samoli et al., 2008, 188455). the 1-day lag
combined risk estimate was larger than the distributed lag (lag, 0, 1, and 2 days) estimate. Overall, an
examination of the PMi0 risk estimates stratified by cause-specific mortality and age, for all U.S.-
and Canadian-based studies, further supports the findings of the multicity studies discussed in the
2004 PM AQCD (U.S. EPA, 2004, 056905) (i.e., consistent positive associations between short-term
exposure to PMi0 and mortality) and this ISA, however, it must be noted that a large degree of
variability exists between cities when examining city-specific risk estimates.
      The variability in PMi0 mortality risk estimates reported within and between multicity studies
may be due to the difference in the cities analyzed and the potential regional differences in PM
composition. The NMMAPS studies have found that geographic regions and seasons are the two
most important factors that determine the variability in risk estimates, with estimates being larger in
the eastern U.S. and during the summer. These findings were fairly consistent across studies, but
Zeka et al. (2006, 088749) observed the strongest association during the transition period (spring and
fall); however, this may be due to the difference in geographic coverage or the difference in the
model specification used compared to Peng et al. (2005, 087463).
      Finally, examination of potential confounders showed that the size of PMi0 risk estimates are
fairly robust to the inclusion of gaseous copollutants in models (Peng et al., 2005, 087463) or by
matching days with similar gaseous pollutant concentrations (Schwartz, 2004, 053506).  These
findings further confirmed that PMi0 risk estimates are not, at least in a  straightforward manner,
confounded by gaseous copollutants.
December 2009                                 6-173

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Study
Peng et al. (2005, 087463). NMMAPS, Lag 1
Dominici et al. (2007, 097361) NMMAPS, Lag 1
Welty and Zeger (2005, 087484) NMMAPS, Lag 1
Schwartz (2004, 078998) 14 U.S. cities, Lag 1
Schwartz (2004, 053506) 14 U.S. cities, Lag 0-1
Zeka et al. (2005, 088068) 20 U.S. cities
LagO
Lag1
Lag 2
Sum of distributed lag 0-2
Zeka et al. (2006, 088749) 20 U.S. cities, Lag 1-2
Effect Estimate (95% Cl)
All seasons

Summer
Fill
Nationwide, 1987-1994
1995-2000
1987-2000
East, 1987-1994
1995°000
1987-2000
West 1987-1994 	 '
1 995-2000 	 I
1 OR? 9nnn j
Bidirectional, 2-stage
Bidirectional, 1 -stage
Matched by temperature, 2-stage
Matched by temperature, 1 -stage
Time-series
Matched by CO (13 cities)
Matched by 03 (13 cities)
Matched by N02 (8 cities)
Matched by S02 (10 cities)
Winter
Spring/Fall
In-hospital
Out-of-hospital
Burnett et al. (2004, 086247) 12 Canadian cities, Lag 1
Samoli et al. (2008, 188455) APHENA, Lag 1
Canada (12 cities)
U.S. (90 cities)












i nun



















II I I I I I I I I
-0.4 0.0 0.4 0.8 1.2 1.6
% Increase
Figure 6-22.    Summary of percent increase in all-cause (nonaccidental) mortality from recent
               multicity studies per 10 ug/m3 increase in PMio. The number after the study
               location indicates lag/average used for PMi0 (e.g., "01" indicates the average of
               lag 0 and 1 days). For Welty and Zeger (2005, 087484), the vertical lines represent
               point estimates for 23 different weather models, and the horizontal band spans
               the 95% posterior intervals of these point estimates.
6.5.2.2.   PM2.5

      A nationwide monitoring system for PM2.5 was not established until 1999. This in conjunction
with the unavailability of nationwide mortality data from the National Center of Health Statistics
(NCHS) starting in 20011, has contributed to the relatively small literature base that has examined
1 In 2008 the EPA facilitated the availability of the mortality data for EPA-funded researchers, which should eventually increase the
 literature base of studies that examine the association between short-term exposure to PM2.5 and mortality.
December 2009
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the association between short-term exposure to PM2.5 and mortality. To date, the studies that have
been conducted examined national (i.e., in multiple cities across the country) or regional (i.e., in one
location of the country) PM2.5 associations with mortality.


      PM2.s - Mortality Associations on a National Scale

      The NMMAPS study conducted by Dominici et al. (2007, 097361) (described in
Section 6.5.2.1), also conducted a national analysis of PM2 5-mortality associations using the same
methodology and data for 1999-2000. The PM25 risk estimates at lag 1 day were 0.29% (95%PI:
0.01-0.57) and 0.38% (95%PI: -0.07 to 0.82) per 10 (ig/m3 increase for all-cause and
cardio-respiratory mortality, respectively. The authors also conducted a sensitivity analysis of the
risk estimates based on the extent of adjustment for temporal trends in the model, changing the
degrees of freedom (df) of temporal adjustment from 1 to 20/yr (the main result used 7 df/yr). In
comparison to the PMi0 results, the PM2 5 risk estimates appeared more sensitive to the extent of
temporal adjustment between 5 and 10 df/yr, but this may be in part due to the much smaller sample
size used for the PM2 5  analysis (i.e., mortality counts from 1999-2000) compared to the PMi0
analysis (i.e., mortality counts from 1987-2000).
      Franklin et al. (2007,  091257) analyzed 27 cities across the U.S. that had PM25 monitoring and
daily mortality data for at least two years of a 6-yr period,  1997-2002. The mortality data up to year
2000 were obtained from the NCHS, while the 2001-2002 data were obtained from six states (CA,
MI, MN, PA, TX, and WA), resulting in 12 out  of the 27 cities having data up to 2002. The start year
for each city included in the study was set at 1999, except for Milwaukee, WI (1997) and Boston,
MA (1998), which is due to PM25 data availability in these two cities. In the case-crossover analysis
in each city, control days for each death were chosen to be every 3rd-day within the same month and
year that death occurred in order to reduce autocorrelation. The first stage regression examined the
interaction of effects with age and gender, while the second stage random effects model combined
city-specific PM2 5 risk estimates and examined possible effect modifiers using city-specific
characteristics (e.g., prevalence of central AC and geographic region). For all of the mortality
categories, the estimates for lag 1  day showed the largest estimates. The combined estimates at lag  1
day were: 1.2% (95%CI:  0.29-2.1), 0.94% (95%CI: -0.14 to 2.0), 1.8% (95%CI: 0.20-3.4), and 1.0%
(95%CI:  0.02-2.0) for all-cause, cardiovascular, respiratory, and stroke deaths, respectively, per
10 (ig/m3. When examining the city-specific risk estimates most of the cities with negative estimates
were also those with a high  prevalence of central AC (Dallas, 89%; Houston, 84%; Las Vegas, 93%;
Birmingham, 77%). It is unclear why these cities exhibit negative (and significant) risk estimates
rather than null effects.
      In the analysis of effect modifiers, Franklin et al. (2007, 091257) found that individuals
> 75 yr showed significantly higher PM2 5 risk estimates than those individuals  < 75 yr. The
estimated effects were also found to vary by geographic location with larger estimates in the East
than in the West, which are  consistent with the regional pattern found in the NMMAPS PMi0 risk
estimates. In addition, a higher prevalence of central AC was associated with decreased PM25 risk
estimates when comparing the lower (25th percentile) versus the higher (75th percentile) AC use rates,
especially in the cities where PM2 5 concentrations peak in the summer. Finally, the risk estimates
were not found to be different between communities with PM25 concentrations < 15 vs. >15 (ig/m3.
The risk estimates for each effect modifier are presented in Figure 6-25. Note the wide confidence
intervals  associated with each of the risk estimates, specifically for Franklin et al. (2007, 091257)
and Ostro et al.  (2006, 087991). which suggests low statistical power for testing the differences
between effect modifiers.
      Franklin et al. (2008,  097426) analyzed 25 cities that had PM2 5 monitoring and daily mortality
data between the years  2000-2005 (with the study period varying from city to city). The choice of the
25 communities was based on the availability of PM25 mass concentrations and daily mortality
records for at least four years, along with PM2 5 speciation data for at least 2 years between 2000 and
2005. Similar to Franklin et al. (2007, 091257). all-cause, cardiovascular, respiratory, and stroke
deaths were examined;  however, of the 25 cities included in the study, only 15 overlap with the 27
cities analyzed in Franklin et al. (2007, 091257). The authors  obtained mortality data from the
NCHS and various state health departments (CA, MA, MI, MN, MO, OH, PA, TX, and WA).
Although the main objective of the study was to examine the role of PM25 chemical species in the
second stage analysis (Section 6.5.2.5), the first stage analysis conducted a time-series regression of
December 2009                                 6-175

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mortality on PM2.5. In addition, the first stage regression performed a seasonal analysis in order to
take advantage of seasonal variation in PM2.5 chemical species across cities and to possibly explain
the city-to-city variation in PM2.5 mortality risk estimates. From this analysis a strong seasonal
pattern was observed with the greatest effects occurring in the spring and summer seasons (Figure
6-25).
      Overall, the risk estimates for all-cause, cardiovascular, and respiratory deaths reported by
Franklin et al. (2008, 097426) are comparable to those presented in the 27 cities study (2007,
091257). as shown in  Figure 6-26. When comparing the 2007 and 2008 studies conducted by
Franklin et al. (2007, 091257; 2008, 097426). although only 15 cities overlap between the two
studies and each study was designed differently (i.e., time-series vs. case-crossover), the magnitude
of the PM2.5 risk estimates reported were similar for the same averaging time, and both studies
reported a regional pattern (East > West) similar to that found in the NMMAPS studies previously
discussed.
      Zanobetti and Schwartz (2009, 188462) conducted a multicity time-series study to examine
associations between PM25 and mortality in 112 U.S. cities. The cities included in this analysis
encompass the majority of cities included in the Franklin et al. (2007, 091257; 2008, 097426)
analyses. In this analysis a city represents a single county; however, 14 of the cities represent a
composite of multiple counties. In addition to examining PM25, the investigators also analyzed
PM10_2.5; these results  are discussed in Section 6.5.2.3. Zanobetti and Schwartz (2009,  188462)
analyzed PM2 5 associations with all-cause, cardiovascular disease (CVD), MI, stroke, and
respiratory mortality for the years 1999-2005. To be included in the analysis, each of the cities
selected had to have at least 265 days of PM2 5 data per year and at least 300 days of mortality data
per year. The authors conducted a city- and season-specific Poisson regression to estimate excess
risk for  PM25 lagged 0- and 1-days, adjusting for smooth functions (natural cubic splines) of days
(1.5 df per season), the same-day and previous day temperature (3 df each), and day-of-week. The
city specific estimates were then combined using a random effects model. Based on the assumption
that climate affects PM exposures (e.g., ventilation and particle characteristics), the investigators
combined city-specific estimates into six regions  based on the Koppen climate classification scheme
(e.g., "Mediterranean  climates" for CA, OR,  WA, etc.).
      The overall combined excess risk estimates were: 0.98 % (95% CI: 0.75, 1.22) for all-cause;
0.85 % (95% CI: 0.46-1.24) for CVD, 1.18 % (95% CI: 0.48-1.89) for MI; 1.78 % (95% CI: 0.96-
2.62) for stroke, and 1.68 % (95% CI: 1.04-2.33) for respiratory mortality for a 10 ug/m3 increase in
PM25 at lag 0-1. When the risk estimates were combined by season, the spring estimates were the
largest for all-cause and for all of the cause-specific mortality outcomes examined. For example,  the
risk estimate for all-cause mortality for the spring was  2.57% (95% CI: 1.96-3.19) with the estimates
for the other seasons ranging from 0.25% to 0.95%.  When examining cities that had both PM2 5 and
PM10_2.5 data (i.e., 47 cities), the addition of PM10_2.5  in the model did not alter the PM25 estimates
substantially,  only decreasing slightly from 0.94% in a single pollutant model to 0.77% in a
copollutant model with PMi0_2.5. When the risk estimates were combined by climatic regions, the
estimated PM25risk for all-cause mortality were similar (all above 1% per 10 ug/m3 increase) for all
the regions except for the "Mediterranean" region (0.5%) which includes cities in CA, OR and WA,
though the estimates in that region were significantly heterogeneous (Figure 6-24).
December 2009                                  6-176

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Climatic Region
            All-cause
CVD
Respiratory
Humid subtropical and maritime
V\ferm summer continental
Hot summer continental
Dry
Dry, continental
Mediterranean
                             -2024
                                    % Increase
                                       -2024
                                              % Increase
                                                                                  -2
                               024
                                 % Increase
                                                                       Source: Data from Zanobetti and Schwartz (2009,188462).
Figure 6-23.
Percent increase in all-cause (nonaccidental) and cause-specific mortality per
10 ug/m3 increase in the average of 0- and 1-day lagged PIVb.s, combined by
climatic regions.
December 2009
                                   6-177

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      The PM2.5 risk estimate for all-cause mortality reported by Zanobetti and Schwartz (2009,
188462) for 112 cities (0.98% per 10 (ig/m3 increase in the average of 0- and 1-day lags) is generally
consistent with that reported by Franklin et al. (2007, 091257) for 27 cities (0.82% [0.02-1.63]) and
Franklin et al. (2008, 097426) for 25 cities (0.74% [95% CI: 0.41-1.07]) using the same 0- and 1-
day avg exposure time. The seasonal pattern (i.e., higher risk estimates in the spring) found in this
study is also consistent with the result from Franklin et al. (2008, 097426). Figure 6-23 highlights the
risk estimates for all-cause, CVD, and respiratory morality combined by region. The regional
division based on climatic types used in this  study makes it difficult to directly compare the regional
pattern of results from previous studies. However, an examination of empirical Bayes-adjusted effect
estimates for each of the cities included in the analysis further confirms the heterogeneity observed
between some cities and regions of the country (Figure 6-24). It is noteworthy that, unlike
NMMAPS, which focused on PMi0 and indicated larger risk estimates in the northeast, Zanobetti
and Schwartz (2009, 188462) found that the all-cause mortality risk estimates were fairly uniform
across the climatic regions, except for the "Mediterranean" region.
    -2.5  -1.5  -0.5  0.5  1.5   2.5  3.5  4.5      -2.5  -1.5  -0.5  0.5   1.5  2.5  3.5   4.5      ~2'5  "1-5 -0.5  0.5  1.5   2.5  3.5  4.5

      % Increase in Total Mortality        % Increase In Cardiovascular Mortality         % Increase In Respiratory
                                                                               Mortality

Figure 6-24.    Empirical Bayes-adjusted city-specific percent increase in total (nonaccidental),
               cardiovascular, and respiratory mortality per 10 ug/m3 increase in the average of
               0-and 1-day lagged PM2.6 by decreasing mean 24-h avg PM2.s concentrations.
               Based on estimates calculated from Zanobetti and Schwartz (2009,188462) using
               the approach specified in Le Tertre et al. (2005, 087560).
December 2009                                  6-178

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Key to Figure 6-24
City
Rubidoux, CA
Bakersfield, CA
Los Angeles, CA
Fresno, CA
Atlanta, GA
Steubenville, OH
Cincinnati, OH
Birmingham, AL
Middletown, OH
Indianapolis, IN
Cleveland, OH
Dayton, OH
Columbus, OH
Detroit, Ml
Akron, OH
Louisville, KY
Chicago, IL
Pittsburgh, PA
Harrisburg, PA
Baltimore, MD
Youngstown, OH
Knoxville, TN
Gary, IN
Charlotte, NC
Warren, OH
Washington, DC
Wilmington, DE
Carlisle, PA
Mean
24.7
21.7
19.7
18.7
17.6
17.1
17.1
16.5
16.5
16.4
16.3
16.3
16.2
16.2
16.0
15.9
15.8
15.7
15.6
15.6
15.6
15.5
15.5
15.3
15.2
15.2
15.1
15.1
98th
68.0
80.3
51.1
64.9
38.2
41.4
39.9
38.8
38.4
38.2
40.5
38.3
38.3
41.0
39.0
38.0
39.1
43.1
40.2
38.8
38.1
32.9
37.5
32.7
37.4
37.2
37.6
40.0
City
Taylors, SC
Toledo, OH
Anaheim, CA
New York, NY
Washington, PA
Wnston, NC
Elizabeth, NJ
Philadelphia, PA
St. Louis, MO
Allentown, PA
Richmond, VA
Spartanburg, SC
Durham, NC
Little Rock, AR
Easton, PA
Raleigh, NC
Greensboro, NC
Mercer, PA
Annandale, VA
Nashville, TN
Dumbarton, VA
Columbia, SC
Milwaukee, Wl
New Haven, CT
Grand Rapids, Ml
El Cajon, CA
Gettysburg, PA
State College, PA
Mean
15.0
14.9
14.9
14.7
14.7
14.7
14.6
14.6
14.5
14.4
14.3
14.2
14.2
14.2
14.2
14.1
14.1
14.1
14.0
13.9
13.8
13.7
13.7
13.6
13.6
13.5
13.4
13.4
98th
32.2
36.6
44.1
38.1
37.0
34.1
38.2
36.6
33.7
38.9
33.0
31.4
32.9
31.8
39.7
31.8
31.0
36.4
34.6
31.0
31.9
30.7
36.3
36.8
36.4
34.9
36.5
38.5
City
Waukesha, Wl
Baton Rouge, LA
Memphis, TN
Erie, PA
Dallas, TX
Houston, TX
Chesapeake, VA
Wlkes-Barre, PA
Norfolk, VA
Sacramento, CA
Springfield, MA
New Orleans, LA
Ft. Worth, TX
Pensacola, FL
Davenport, IA
Avondale, LA
Boston, MA
Holland, Ml
Charleston, SC
Tampa, FL
Tulsa, OK
Kansas, MO
Scranton, PA
Hartford, CT
Minneapolis, MN
Worcester, MA
Salt Lake, UT
Providence, Rl
Mean
13.4
13.4
13.3
12.9
12.8
12.8
12.8
12.8
12.7
12.6
12.5
12.5
12.4
12.3
12.3
12.3
12.3
12.1
12.1
12.1
12.1
12.0
11.9
11.8
11.6
11.5
11.5
11.5
98th
35.3
30.1
32.4
36.1
28.7
27.5
29.8
32.5
29.6
45.0
35.1
29.0
27.7
31.2
32.1
28.6
30.2
35.0
27.9
25.8
32.3
28.6
33.0
33.5
31.6
30.2
52.4
30.5
City
Phoenix, AZ
Tacoma, WA
Port Arthur, TX
Cedar Rapids, IA
Dodge, Wl
Oklahoma, OK
Des Moines, IA
Jacksonville, FL
Omaha, NE
Denver, CO
Pinellas, FL
Austin, TX
Orlando, FL
Klamath, OR
Seattle, WA
Medford, OR
Bath, NY
Provo, UT
Miami, FL
El Paso, TX
Spokane, WA
San Antonio, TX
Portland, OR
Davie, FL
Eugene, OR
Palm Beach, FL
Bend, OR
Albuquerque, NM
Mean
11.4
11.4
11.1
11.0
10.9
10.8
10.5
10.5
10.5
10.5
10.4
10.4
10.3
10.2
10.1
10.0
9.6
9.5
9.4
9.0
8.9
8.9
8.9
8.4
8.1
7.8
7.7
6.6
98th
30.7
38.1
25.7
31.0
32.9
26.1
27.9
25.3
28.0
26.4
23.1
24.5
24.3
40.7
27.9
37.3
29.3
38.5
20.5
24.4
30.6
21.9
25.4
19.1
29.9
18.4
23.5
17.9
Note: The top effect estimate in the figures represents the overall effect estimate for that mortality outcome across all cities. The remaining effect estimates are ordered by the highest (i.e., Rubidoux, CA) to lowest (i.e.,
Albuquerque, NM) mean 24-h PM2 5 concentrations across the cities examined. In the key the cities are reported in this order, which represents the policy relevant concentrations for the annual standard, but the policy
relevant PM25 concentrations for the daily standard (i.e., 98th percentile of the 24-h average) are also listed for each city (from Zanobetti and Schwartz (2009,188462))


       PM2.s-Mortality Associations on a Regional Scale: California

       Ostro et al. (2006, 087991) examined associations between PM2.5 and daily mortality in nine
heavily populated California counties (Contra Costa, Fresno, Kern, Los Angeles, Orange, Riverside,
Sacramento, San Diego, and Santa Clara) using data from 1999 through 2002. The authors used a
two-stage model to examine all-cause, respiratory, cardiovascular, ischemic  heart disease, and
diabetes mortality individually and by potential effect modifier (i.e., age, gender, race, ethnicity, and
education level). The a priori exposure periods examined included the average of 0- and 1-day lags
(lag 0-1) and the 2-day lag (lag 2). The authors selected these non-overlapping lags (i.e., rather than
selecting lag 1 as the single-day lag) because previous studies have reported stronger associations at
lags of 1  or 2 days or with cumulative exposure over three days. It is unclear why the investigators
chose these non-overlapping lags (i.e., single-day lag of 2 instead of 1) even though they state they
based the selection of their lag days on results presented in previous studies, which found the
strongest association for PM lagged 1 or 2 days. Using the average of 0- and 1-day lags Ostro et al.
December 2009
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(2006, 087991) reported combined estimates of: 0.6% (95% CI: 0.2-1.0), 0.6% (95% CI: 0.0-1.1),
0.3% (95% CI: -0.5 to 1.0), 2.2% (95% CI: 0.6-3.9), and 2.4% (95% CI: 0.6-4.2) for all-cause,
cardiovascular, ischemic heart disease, respiratory, and diabetes deaths, respectively, per 10 (ig/m3.
The authors also conducted a sensitivity analysis of risk estimates based on the extent of temporal
adjustment, which showed monotonic reductions for all of the death categories examined when 4, 8,
and 12 degrees of freedom per year were used.
      Five of the nine counties examined in the Ostro et al. (2006, 087991) analysis contain cities
that are among the 27 cities examined in the Franklin et al. (2007, 091257) analysis for the same
period, 1999-2002. While the lags used were different between these two studies, both presented
PM2.5 risk estimates in individual cities or counties (graphically in the Franklin et al. study  (2007,
091257); in a table in the Ostro et al. study (2006, 087991)). which allowed for a cursory evaluation
of consistency between the two analyses. In Franklin et al. (2007, 091257). PM2.5 risk estimates at
lag 1 day for the cities Los Angeles and Riverside were slightly negative, whereas Fresno,
Sacramento, and San Diego showed positive values above 1% per 10 (ig/m3 increase in PM25. The
2-day lag result presented in Ostro et  al. (2006, 087991) is qualitatively consistent, with Los Angeles
and Riverside, both of which show slightly negative estimates, while the other 3 locations all show
positive, but somewhat smaller estimates, than those reported by Franklin et al. (2007, 091257). The
estimates for the average of 0- and  1-day lags for these five counties in Ostro et al. (2006, 087991).
which contain cities examined in Franklin et al. (2007, 091257). were all positive. Thus,  these two
PM2.5 studies showed some consistencies in risk estimates even though they used different  lag
periods and a different definition for the study areas of interest (i.e., counties vs. cities). The risk
estimates for Franklin et al. (2007, 091257) and Ostro et al. (2006, 087991). stratified by various
effect modifiers (e.g., gender, race, etc.), are summarized in Figure 6-25. Of note is the contrast in
the results presented for the effect modification analysis for "in-hospital" versus "out-of-hospital"
deaths for Ostro et al. (2006, 087991). which differs from the results presented in the PM10 study
conducted by Zeka et al. (2006, 088749). Ostro et al. (2006,  087991) observed comparable risk
estimates for "in-hospital" vs. "out-of-hospital" deaths, whereas Zeka et al. (2006, 088749) observed
a large difference between the two in the 20 cities study discussed earlier. This difference in effects
observed between the two studies is more than likely due to the compositional differences in PMi0 in
the cities examined in Zeka et al. (2006, 088749) (i.e., PMi0 more or less dominated by PM25 and the
subsequent composition of PM25).
December 2009                                 6-180

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Study
Effect Modifier
Effect Estimate (95% Cl)
Ostro et al. (2006, 0879911, 9 CA counties, Lag 0-1
                                         All-cause
                                         Age > 65

                                         Male
                                         Female

                                         White
                                         Black
                                         Hispanic

                                         In-hospital
                                         Out-of-hospital

                                         > High School
                                         < High School
Franklin et al. (2007, 0912571, 27 U.S. cities, Lag 1
                                         All-cause

                                         Age > 75
                                         Age < 75

                                         Male
                                         Female

                                         East
                                         West

                                         PM25>15|jg/m3
                                         PM25<15|jg/m3

                                         25th percentile air conditioning
                                         75th percentile air conditioning

                 Summer peaking PM2 5 cities:  25th percentile air conditioning
                                         75th percentile air conditioning

Franklin et al. (2008, 0974261, 25 U.S. cities, Lag 0-1
                                         All-cause

                                         Wnter
                                         Spring
                                         Summer
                                         Fall

                                         West
                                         East & Central

Zanobetti and Schwartz (2009,1884621,112 U.S. cities, Lag 0-1
                                         All-cause

                                         Wnter
                                         Spring
                                         Summer
                                         Autumn
                                                              -2.0
                                                                                   0.0

                                                                                 % Increase
                                                                                              i
                                                                                             1.0
                                                          I
                                                         2.0
                                                                                                                3.0
                                       I
                                      4.0
Figure 6-25.    Summary of percent increase in all-cause (nonaccidental) mortality per 10  ug/m3
                   increase in PM2.s  by various effect modifiers.
December 2009
             6-181

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      PM2.s-Mortality Associations in Canada

      An analysis of multiple pollutants, including PM2.5, in 12 Canadian cities found the most
consistent associations for NO2 (Burnett  et al, 2004, 086247). In this analysis, PM2.5 was only
measured every 6th day in much of the study period, and the simultaneous inclusion of NO2 and
PM2.5 in a model on the days when PM2 5 data were available eliminated the PM2 5 association (from
0.60% to -0.10% per 10 (ig/m3 increase in PM25). However, the investigators noted that during the
later study period of 1998-2000  when daily TEOM PM25 data were available for 11 of the 12 cities,
a simultaneous inclusion of NO2 and PM25 resulted in considerable reduction of the NO2 risk
estimate, while the PM2.5 risk estimate was only slightly reduced from 1.1% to 0.98% (95% CI: -0.16
to 2.14). Thus, the relative importance of NO2 and PM25 on mortality effect estimates has not been
resolved when using the Canadian data sets.


      Summary of PM2.5 Risk Estimates

      The risk estimates for all-cause mortality for all ages ranged from 0.29% Dominici et al.
(2007, 097361) to 1.21% Franklin et al. (2007, 091257) per 10 (ig/m3 increase in PM2.5 (Figure
6-26). An examination of cause-specific risk estimates found that PM2 5 risk estimates for
cardiovascular deaths  are similar to those for all-cause deaths (0.30-1.03%), while the effect
estimates for respiratory deaths were consistently larger (1.01-2.2%), albeit with larger confidence
intervals, than those for all-cause or cardiovascular deaths using the same lag/averaging indices.
Figure 6-27 summarizes the PM25 risk estimates for all U.S.- and Canadian-based studies by
cause-specific mortality.
      An examination of lag structure observed results similar to those reported for PMi0 with most
studies reporting either single day lags or two-day avg lags with the strongest effects observed on lag
1 or lag 0-1. In addition, seasonal patterns of PM25 risk estimates were found to be similar to those
reported for PMip, with the warmer season showing the strongest association. An evaluation of
regional associations found that in most cases the eastern U.S. had the highest PM25 mortality risk
estimates, but this was dependent on the geographic designations made in the study. When grouping
cities by climatic regions, similar PM2 5 mortality risk estimates were observed across the country
except in the Mediterranean region, which included CA, OR, and WA.
      Of the studies evaluated, only Burnett et al. (2004, 086247). a Canadian multicity study,
analyzed gaseous pollutants and found mixed results, with possible confounding of PM25 risk
estimates by NO2. Although the  recently  evaluated U.S.-based multicity studies did not analyze
potential confounding of PM25 risk estimates by gaseous pollutants, evidence from single-city
studies evaluated in the 2004 PM AQCD (U.S. EPA, 2004, 056905) suggest that gaseous
copollutants do not confound the PM2 5-mortality association, which is further supported by studies
that examined the PMio-mortality relationship.
December 2009                                 6-182

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Study
Cause-Specific Mortality
Effect Estimate (95% Cl)
Dominici et al. (2007, 0991351, NMMAPS
Franklin et al. (2007, 0912571, 27 U.S. cities
Franklin et al. (2008, 0974261, 25 U.S. cities
                                           All-cause, lag 1

                                           Cardio-respiratory, lag 1
                                           All-cause, lag 1

                                           Cardiovascular, lag 1

                                           Respiratory, lag 1




                                           All-cause, lag 0-1

                                           Cardiovascular, lag 0-1

                                           Respiratory, lag 0-1
                                           All-cause, lag 0-1

                                           Cardiovascular, lag 0-1

                                           Respiratory, lag 1-2
Zanobetti and Schwartz (2009, 1884621,112 U.S. cities
Ostro et al. (2006, 0879911, 9 CA counties
                                           All-cause, lag 0-1

                                           Cardiovascular, lag 0-1

                                           Respiratory, lag 0-1
                                           All-cause, lag 0-1

                                           Cardiovascular, lag 0-1

                                           Respiratory, lag 0-1
                                                                         -0.5        0.5   1.0    1.5   2.0   2.5   3.0    3.5   4.0

                                                                            % Increase
Figure 6-26.    Summary of percent increase  in all-cause (nonaccidental) and cause-specific
                   mortality per 10 ug/m3 increase  in PM2.5from recent multicity studies.
December 2009
             6-183

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Study
Location
Burnett and Goldberg (2003, 042798)* 8 Cities, Canada
Klemm and Mason (2003, 042801)* 6 Cities, U.S.
Moolgavkar (2003, 051316)* Los Angeles, CA
Ito (2003, 042856)* Detroit, Ml
Fairley (2003, 042850)* Santa Clara County, CA
Tsai et al. (2000, 006251)* Newark, NJ
Elizabeth, NJ
Camden, NJ
Chock et al. (2000, 010407)* Pittsburgh, PA
Dominici et al. (2007, 097361) 100 Cities, U.S.
Zanobetti and Schwartz (2009, 188462) 112 Cities, U.S.
Franklin et al. (2007, 091257) 27 Cities, U.S.
25 Cities, U.S.
Burnett et al. (2004, 086247) 1 2 Cities, Canada
Ostro et al. (2006, 087991) 9 Counties, CA
Slaughter et al. (2005, 073854) Spokane, WA
Klemm et al. (2004, 056585) Atlanta, GA
Villeneuve et al. (2003, 055051) Vancouver, Canada
Tsai et al. (2000, 006251)* Newark, NJ
Elizabeth, NJ
Camden, NJ
Dominici et al. (2007, 097361) 100 Cities, U.S.
Klemm and Mason (2003, 042801)* 6 Cities, U.S.
Ostro et al. (1 995, 0791 97)* Southern CA
Lipfert et al. (2000, 004088)* Philadelphia, PA
Moolgavkar (2003, 051316)* Los Angeles, CA
Ito (2003, 042856)* Detroit, Ml
Mar et al. (2003, 042841)* Phoenix, AZ
Fairley (2003, 042850)* Santa Clara County, CA
Zanobetti and Schwartz (2009, 188462) 112 Cities, U.S.
Franklin et al. (2007, 091257) 27 Cities, U.S.
Franklin et al. (2008, 097426) 25 Cities, U.S.
Ostro et al. (2007, 091 354) 9 Counties, CA
Ostro et al. (2006, 087991) 9 Counties, CA
Holloman et al. (2004, 087375) 7 Counties, NC
Wilson et al. (2007, 1 571 49) Phoenix, AZ
Villeneuve et al. (2003, 055051) Vancouver, Canada
Klemm and Mason (2003, 042801)* 6 Cities, U.S.
Ostro et al. (1 995, 0791 97)* Southern California
Moolgavkar (2003, 051 31 6)* Los Angeles, CA
Ito (2003, 042856)* Detroit, Ml
Fairley (2003, 042850)* Santa Clara County, CA
Zanobetti and Schwartz (2009, 188462) 112 Cities, U.S.
Franklin et al. (2007, 091257) 27 Cities, U.S.
Franklin et al. (2008, 097426) 25 Cities, U.S.
Ostro et al. (2006, 087991) 9 Counties, CA
Villeneuve et al. (2003, 055051) Vancouver, Canada
"Studies represent the collective
evidence from the 2004 PM AQCD (2004, 056905).
Lag Age Effect Estimate (95% Cl)
1
0-1
1
3 ->
0
0
0

1
0-1
1
0-1
1
0-1
0-1 65+
0
0
1
0-1
0 -i
1
1 -i
1
0-1
1 J
0-1
3
0-1



0 J


0-1
0-1
1-2
0-1

— •— Nonaccidental
-•—
i— • 	
—
*


«•
.0.
-•-
*

— •— Cardio-respiratory

•«-
'— • — Cardiovascular
«-
r-» 	


i — • 	
r»-


n 	 -„._„,
— • —
*

— • 	

I I I I I I I I I I I
-5-3-1 1 3 5 7 9 11 13 15
% Increase
Figure 6-27.   Summary of percent increase in all-cause (nonaccidental) and cause-specific
              mortality per 10 ug/m3 increase in PM2.6 for all U.S.- and Canadian-based studies.
              The three vertical lines for the Wilson et al. (2007,157149) estimate represent the
              central, middle, and outer Phoenix estimates.
6.5.2.3.   Thoracic Coarse Particles (PM10.2.5)

      In the 2004 PM AQCD (U.S. EPA, 2004, 056905). a limited number of studies, mostly single-
city analyses, were evaluated that examined thoracic coarse (PMi0_2.5) PM for its association with
mortality. Of these studies a small number examined both PM25 and PMi0_2.5 effects, and found some
evidence for PMi0_2.5 effects of the same magnitude as PM25. However, multiple limitations in these
studies were identified including measurement and exposure issues for PM10_2.5 and the correlation
between PM2 5 and PMi0_2.5. These limitations increased the uncertainty surrounding the
concentrations at which PMi0_2.5-mortality associations are observed.
December 2009
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      A thorough analysis of PM10_2.5 mortality associations requires information on the speciation of
PMio_2.5. This is because, while a large percent of the composition of coarse particles may consist of
crustal materials by mass, depending on available sources, the surface chemical characteristics of
PMio_2.5 may also vary from city to city. Thus, without information on the chemical speciation of
PMio_2.5, the apparent variability in observed associations between PMi0_2.5 and mortality across cities
is difficult to characterize. Although this type of information is not available in the current literature,
the relative importance of the associations observed between PMi0_2.5 and mortality in the following
studies is of interest.


      PM10.2.5 Concentrations  Estimated Using the Difference Method

      The Zanobetti and Schwartz (2009, 188462) multicity analysis, described for PM2.5
section (Section 6.5.2.2), also examined the association between computed PMi0_2.5 and all-causes,
cardiovascular disease (CVD), MI, stroke, and respiratory mortality for the years 1999-2005. Of the
112 cities included in the PM2.5 analysis only 47 cities had both PM2.s and PMi0 data available.
PMio_2.5 was estimated in these cities by differencing the county wide averages of PMi0 and PM2.5. In
addition to examining the association between PMi0_2.5 and mortality for the  average of lags 0 and
1 day, the investigators also considered a distributed lag of 0-3 days. The risk estimates for PM10_2.5
were presented for both a single pollutant model and a copollutant model with PM2.5, and were also
combined by season and climatic regions  as was done in the PM2.5 analysis.
      The study found a significant association between the computed PMiq_2.5 and all-cause, CVD,
stroke, and respiratory mortality.  The combined estimate for the 47 cities using the average of 0- and
1-day lag PMio.2.5 for all-cause mortality was 0.46% (95% CI: 0.21-0.71) per 10 (ig/m3 increase. The
estimate obtained using the distributed lag model was smaller (0.31% [95% CI: 0.00-0.63]). The
seasonal analysis showed larger risk estimates in the spring for all-cause (1.01%) and respiratory
mortality (2.56%) (i.e., the  same  pattern observed in the PM2.5 analysis); however, for CVD
mortality, the estimates for  spring (0.95%) and summer (1.00%) were comparable. When the risk
estimates were combined by climatic region (Figure 6-28), for all-cause mortality, the "dry,
continental" region (which  included Salt Lake City, Provo, and Denver, all of which had relatively
high estimated PMi0_2.5 concentrations) showed the largest risk estimate (1.11% [95% CI:
0.11-2.11]), but the "dry" region  (which included Phoenix and Albuquerque, the two cities with high
PMio_2.5 concentrations) and the "Mediterranean" region (which included cities in  CA, OR, and WA)
did not show positive associations. The other three regions (i.e., "hot summer, continental," "warm
summer, continental," and "humid, subtropical and maritime"), which included cities that correspond
to the mid-west, southeast,  and northeast geographic regions as defined in previous NMMAPS
analyses, all showed significantly positive associations. Similar regional patterns of associations
were found for CVD and respiratory mortality, which are further confirmed when  examining the
empirical Bayes-adjusted city-specific estimates in Figure 6-29. The regional pattern of associations
for MI and stroke are less clear, because of the wider confidence intervals due to the smaller number
of deaths in these specific categories. The lack of a PMi0_2.5-mortality association in the "dry" region
reported in this study is  in contrast to the results from three studies that analyzed Phoenix data and
found associations, as reviewed in the 2004 PM AQCD (U.S. EPA, 2004, 056905). and Wilson et al.
(2007, 157149) (discussed below).
      Although the results from this analysis are informative because it is the first multicity U.S.-
based study that examined the association between short-term exposure to PMi0_2.5 and mortality on a
large scale, some limitations do exist. Specifically, it is not clear how the computed PMi0_2.5
measurements used by Zanobetti and Schwartz (2009, 188462) compare with the PMi0_2.5
concentrations obtained by  directly measuring PM10_2.5 using a dichotomous sampler, or the PM10_2.5
concentrations computed using the difference of PMi0 and PM2.5 measured at co-located samplers.
      Additional studies evaluated the association between short-term exposure to PMi0_2.5 and
mortality using PMi0_2.5  concentrations estimated by subtracting PMi0 from PM2.5  concentrations at
co-located monitors. Although PMi0_2.5 concentrations estimated using this approach are not ideal,
the results from these studies are informative in evaluating the PMi0_2.5 mortality association.
December 2009                                  6-185

-------
     Climatic Region
All-cause
CVD
Respiratory
Humid subtropical and maritime
V\ferm summer continental
Hot summer continental
Dry
Dry continental
Mediterranean
                        i   i   i    I   i    i   i   i
                       -3-2-10   1   2   3   4
                                               I   I   T
                                                   -3-2-101234    -3-2-101234
                                % Increase
                         % Increase
                         % Increase
                                                                      Source: Data from Zanobetti and Schwartz (2009,188462).
Figure 6-28.   Percent increase in all-cause (nonaccidental) and cause-specific mortality per
                10 ug/m3 increase in the average of 0- and 1-day lagged PMio-2.5, combined by
                climatic regions.
December 2009
                6-186

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               0.5 1.0 1.5 2.0 2.5 3.0 3.5   -2.5
                                               05 10 15 2.0 2.5 3.0 3.5
                                                                               0.5 1.0 1.5 2.0 2.5 3.0 3.5
     % Increase in Total Mortality
% Increase In Cardiovascular Mortality     % Increase In Respiratory Mortality
Figure 6-29.    Empirical Bayes-adjusted city-specific percent increase in total (nonaccidental),
               cardiovascular, and respiratory mortality per 10 ug/m3 increase in the average of
               0- and 1-day lagged PM10.2.s by decreasing 98th percentile of mean 24-h avg
               PM10.2.6 concentrations. Based on estimates calculated from Zanobetti and
               Schwartz (2009,188462) using the approach specified in Le Tertre et al. (2005,
               087560).
December 2009
            6-187

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Key for Figure 6-29
City
El Paso, TX
St. Louis, MO
Phoenix, AZ
Detroit, Ml
Gary, IN
Omaha, NE
Albuquerque, NM
New Haven, CT
Bakersfield, CA
Des Moines, IA
Denver, CO
Salt Lake, UT
98th
105.1
81.9
80.1
77.5
71.3
65.6
64.3
58.4
55.9
55.0
53.8
52.6
Mean
25.4
15.2
33.3
17.3
6.9
24.7
22.9
11.9
16.1
16.2
18.1
19.2
City
Cleveland, OH
Davenport, IA
Birmingham, AL
Provo, UT
Chicago, IL
Easton, PA
Steubenville, OH
Columbia, SC
Los Angeles, CA
Spokane, WA
Columbus, OH
Pittsburgh, PA
98th
51.2
49.9
49.6
49.3
46.1
43.9
43.5
42.9
42.5
41.8
40.0
32.0
Mean
15.2
15.3
14.2
18.2
12.4
12.0
12.1
8.4
13.5
13.8
11.2
9.4
City
Sacramento, CA
Tampa, FL
Toledo, OH
Washington, PA
Allentown, PA
Atlanta, GA
Davie, FL
Taylors, SC
Memphis, TN
Seattle, WA
Baltimore, MD
Cincinnati, OH
98th
31.5
29.1
28.8
27.8
27.8
27.4
25.5
25.4
24.3
23.7
23.5
23.3
Mean
10.2
12.9
7.6
6.5
4.5
8.6
9.4
8.0
9.3
9.0
8.9
7.8
City
Louisville, KY
Wlkes-Barre, PA
New York, NY
Wlmington, DE
Raleigh, NC
Scranton, PA
Harrisburg, PA
Akron, OH
Charleston, SC
Wnston, NC
Erie, PA

98th
23.3
22.2
22.0
21.8
20.9
19.2
18.6
17.7
17.6
16.5
14.9

Mean
8.3
6.2
6.4
7.0
6.9
6.1
5.4
5.3
6.6
7.4
3.1

Note: The top effect estimate in the figures represents the overall effect estimate for that mortality outcome across all cities. The remaining effect estimates are ordered by the highest (i.e., El Paso, TX) to
lowest (i.e., Erie, PA) 98th percentile of the mean 24-h PMW7 5 concentrations across the cities examined, which is the policy relevant concentration for the daily standard [from Zanobetti and Schwartz (2009,
18846211.


      Slaughter et al. (2005, 073854) examined the association of various PM size fractions (PMi,
PM2.5, PMio, PMio_2.5) and CO with ED visits, HAs, and mortality in Spokane, WA for the period
1995-2001. Although the authors did not report mortality risk estimates for PM10_2.5, they did not find
an association between any PM size fraction (or CO) and mortality or cardiac HAs at lags of
0-3 days.
      Wilson et al. (2007, 157149) examined the association between size-fractionated PM (PM2.5
and PMio_2.5) and cardiovascular mortality in Phoenix for the study period 1995-1997, using
mortality data aggregated for three geographic regions: "Central Phoenix," "Middle Ring," and
"Outer Phoenix," which were constructed as a composite of zip codes of residence in order to
compare population size among the three areas. The authors reported apparently different patterns of
associations between PM2.5 and PMi0_2.s in terms  of the size of the risk estimate across the three areas
and temporal patterns of associations. In the "Middle Ring" where PMi0_2.5 showed the strongest
association, the estimated risk per 10 (ig/m3 increase for a 1 day lag was 3.4% (95% CI: 1.0-5.8).
The estimated risk for PM2.5 found for "Central Phoenix" was 6.6% (95% CI: 1.1-12.5) for lag 1.
The authors speculated that the apparent difference in estimated risks across the areas might be due
to the lower SES in "Central Phoenix" or the lower exposure error, but the relatively wide
confidence bands of these estimates  make it difficult to establish such relationships (Section 8.1.7 for
a detailed discussion on SES and susceptibility to PM exposure).
      Kettunen et al. (2007, 091242) analyzed UFPs, PM2.5, PMi0, PMi0_2.5, and gaseous pollutants
for their associations with stroke mortality in Helsinki during the study  period of 1998-2004. The
authors did not observe an association between air pollution and mortality for the whole year or cold
season, but they did find associations for PM2.5 (13.3% [95% CI: 2.3-25.5] per 10  ug/m3), PMi0, and
CO during the warm season, most strongly at lag 1 day. An association  was also observed for
PMio_2.5 during the warm season (7.8% [95% CI:  -7.4 to 25.5] per 10 (ig/m3 at lag  1 day); however, it
was weaker than PM2 5.
      The Perez et al. (2008, 156020) analysis tested the hypothesis that outbreaks of Saharan dust
exacerbate the effects of PM25  and PM10_2.5 on daily mortality. Changes of effects between Saharan
and non-Saharan dust days were assessed using a time-stratified case-crossover design involving
24,850 deaths between March 2003 and December 2004 in Barcelona, Spain. Saharan dust days
were identified from back-trajectory and satellite images. Chemical speciation, but not an analysis
for microbes or fungi, was conducted approximately once a week during the  study period. On
Saharan dust days, mean concentrations were 1.2 times higher for PM25 (29.9 (ig/m3) and 1.1 times
higher for PM10_25 (16.4 (ig/m3) than on non-Saharan dust days. During Saharan dust days (90 days
out of 602), the PM 10-2.5 risk estimate was 8.4% (95% CI: 1.5-15.8) per  10  (ig/m3 increase at lag 1
day, compared with 1.4%  (95% CI: -0.8 to 3.4) during non-Saharan dust days. In contrast, there was
not an additional increased risk of daily mortality for PM25 during Saharan dust days (5.0%
December 2009
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[95% CI: 0.5-9.7]) compared with non-Saharan dust days (3.5% [95% CI: 1.6-5.5]). However,
differences in chemical composition (i.e., PM25 was primarily composed of nonmineral carbon and
secondary aerosols; whereas PMi0_2.5 was dominated by crustal elements) did not explain these
observations. Note also when examining all days combined, both size fractions were associated with
mortality, but the PM2.5 association was found to  be stronger.


      PM10.2.5 Concentrations Directly Measured

      In Burnett et al. (2004, 086247). which analyzed the association of multiple pollutants with
mortality in 12 Canadian cities, described previously; the authors also examined PMi0_2.5. In this
study the authors collected PMi0_2.5 using dichotomous samplers with an every-6th-day schedule.
When both NO2 and PM10 2 5 were included in the regression model, the PM10 2 5  effect estimate was
reduced from 0.65% (95% CI: -0.10 to 1.4) to 0.31% (95% CI: -0.49 to 1.1) per  10 (ig/m3 increase in
1-day lag PMi0_2.5. These risk estimates are similar to those reported for PM25, which were also
reduced upon the inclusion of NO2 in the two-pollutant model, but to a greater extent, from 0.60%
(95% CI: -0.03 to 1.2) to -0.1% (95% CI:  -0.86 to 0.67).
      Villeneuve et al. (2003, 055051) analyzed the association between PM2.5, PMi0_2.5, TSP, PMi0,
SO42~, and gaseous copollutants in Vancouver, Canada, using a cohort of approximately 550,000
whose vital status was ascertained between 1986 and 1999. In this study PM25 and PMi0_2.5 were
directly measured using dichotomous samplers. The authors examined the association of each air
pollutant with  all-cause, cardiovascular, and respiratory mortality, but only observed significant
results for cardiovascular mortality at lag  0 for both PMi0_2.5 and PM2 5. They  found that PMi0_2.5
(5.4% [95% CI:  1.1-9.8]  per 10 (ig/m3), was more strongly associated with cardiovascular mortality
than PM2.5 (4.8% [95% CI: -1.9 to 12.0] per 10 ug/m3).
      Klemm et al. (2004, 056585) analyzed various components of PM and  gaseous pollutants for
their associations with mortality in Fulton and DeKalb Counties, Georgia for  the 2-yr period,
1998-2000. PMio_2.5 concentrations were obtained from the ARIES database, which directly
measured PMi0_2.5 using dichotomous samplers. In this analysis the authors adjusted for temporal
trend using quarterly, monthly, and biweekly knots, and reported estimates for all-cause, circulatory,
respiratory, cancer, and other causes mortality for each scenario. Overall, PM2 5 was, more strongly
associated with mortality than PMi0_2.5. For example, using the average of 0- and 1-day lags, the risk
estimates for PM25 and PMi0_25 in the monthly knots model for all-cause mortality, ages > 65 yr
were 5.6% (95% CI: 1.9-9.5) and 6.4% (95% CI: -0.5 to 14.1) per 10 (ig/m3 increase, respectively.1


      Summary of PM10.2.5 Risk Estimates

      The results from newly available studies that examined the association  between short-term
exposure to PMi0_2.5 primarily consisted of single-city studies. Collectively these studies found
consistent, positive associations, with the precision of each association varying by study location.
The evidence from those single-city studies conducted in the U.S. and Canada in combination with
the multicity studies evaluated (i.e., in the U.S. and Canada), provide evidence for PMi0_2.5 effects.
However, the various methods used to estimate exposure to PMi0_2.5 (e.g., direct measurement of
PMio_2.5 using dichotomous samplers, calculating the difference between PMi0 and PM2 5
concentrations) in the studies evaluated add uncertainty to the associations observed. Specifically, a
new U.S. multicity study (Zanobetti and Schwartz, 2009, 188462) estimated  PMi0_2.5 by calculating
the difference between the county-average PMi0 and PM2 5 concentrations. Although there are
limitations in the method used by Zanobetti and Schwartz (2009, 188462) associations between
PMio_2.5 and mortality were observed throughout multiple regions of the country. However, some of
the findings of this new multicity study (e.g., no associations in "dry" region  where PMi0_2.5 levels
are high) are not consistent with the findings of the PMi0_2.5 studies evaluated in the 2004 PM AQCD
(U.S. EPA, 2004, 056905). and suggest that the coarse fraction is associated with mortality in areas
of the U.S. where PMi0_2.5 levels are not high. Limitations also exist in the PMi0_2.5  associations
reported due to the small number of PM10_2.5 studies that have investigated confounding by gaseous
1 The monthly knot model was selected for comparison because, overall, PM2.5 showed the strongest association with all-cause mortality
 among the 15 air pollution indices examined when using this model.
December 2009                                  6-189

-------
copollutants or the influence of model specification on PM10_2.5 risk estimates. Additionally, more
data is needed to characterize the chemical and biological components that may modify the potential
toxicity of PMio_2.5. Figure 6-30 summarizes the PMi0_2.5 risk estimates for all U.S.-, Canadian-, and
international-based studies by cause-specific mortality.
Study
                           Location
Lag Age**
                                                                  Effect Estimate (95% Cl)
Klemm et al. (2003,042801)*
Burnett and Goldberg (2003,042798)*
Ito (2003.042856)*
Fairley (2003,042850)*
Chock etal. (2000.010407)*

Zanobetti and Schwartz (2009,188462)
Burnett etal. (2004.086247)
Klemm etal. (2004.056585)
Villeneuve et al. (2003,055051)
Lipfertetal. (2000,004088)*
Ito (2003.042856)*
Mar etal. (2003.042841)*
Fairley (2003,042850)*
Ostro etal. (2003.042824)*
Zanobetti and Schwartz (2009,188462)
Wilson etal. (2007.157149)
Villeneuve et al. (2003,055051)
Ito (2003.042856)*
Fairley (2003,042850)*
Zanobetti and Schwartz (2009,188462)
Villeneuve et al. (2003,055051)
                           6 Cities, U.S.         0-1
                           8 Cities, Canada        1
                           Detroit, Ml            1
                           Santa Clara County, CA   0
                           Pittsburgh, PA         0
                                             0
                           47 Cities, U.S.        0-1
                           12 Cities, Canada       1
                           Atlanta, GA          0-1
                           Vancouver, Can        0
                           Philadelphia, PA        1
                           Detroit, Ml            1
                           Phoenix, AZ           0
                           Santa Clara County, CA   0
                           Coachella Valley, CA     0
                           47 Cities, U.S.        0-1
                           Phoenix, AZ          0-5
                           Vancouver, Can        0
                           Detroit, Ml            2
                           Santa Clara County, CA   0
                           47 Cities, U.S.        0-1
                           Vancouver, Canada      0
                                                 <75
                                                 75+
                                                 65+
                                                 65+
                                                 65+
                                                                                        Nonaccidental
                                                                                       Cardiovascular
                                                                      H—h
                                                                                         Respiratory
                                                                                         -•	$
* Slides represent the collective evidence from the 2004 PM AQCD (2004, 0569051.
**lf age not specified, study included all ages.
                                                       -5  -3-11   3
                                                              % Increase
                                                                                    9  11   13   15
Figure 6-30.   Summary of percent increase in total (nonaccidental) and cause-specific
               mortality per 10 ug/m3 increase in PMi0-2.5 for all U.S.-, Canadian-, and
               international-based studies. The three vertical lines for the Wilson et al. (2007,
               157149) estimate represent the central, middle, and outer Phoenix estimates.
6.5.2.4.   Ultrafine Particles

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) reviewed Wichmann et al.'s (reanalyzed by
Stolzel et al., 2003, 042842: 2000, 013912) study of fine and ultrafine particles (UFPs) (diameter:
0.01-0.1 (im) in Erfurt, Germany, for the study period 1995-1998. Stolzel et al.  (2007, 091374)
extended the study period to include the years 1995-2001 and updated the analysis. Number
concentrations (NC) for four size ranges of UFPs (0.01-0.1, 0.01-0.03, 0.03-0.05, and 0.05-0.1 (im)
as well as mass concentration (MC) for three size ranges (0.01-2.5, 0.1-0.5,  and 10 (im) were
analyzed. The authors found associations with UFP NC and all-cause  as well as cardio-respiratory
mortality, each for a 4 day lag. The risk estimates associated with a 9,748/cm3 increase in UFP NC
was 2.9% (95% CI: 0.3-5.5) for all-cause mortality  and 3.1% (95% CI: 0.3-6.0) for
cardio-respiratory mortality. The UFP-mortality association, and the lag structure of association, is
consistent with the results from their  earlier analysis, but the PM2.5 association found in the previous
study was not observed in the updated analysis. Both UFP and PM2.5 concentrations were higher
during the cold season in this locale.
      Breitner et al. (2009,  188439) analyzed UFP data from Erfurt, Germany, over a 10.5-yr period
(October 1991-March 2002) after the German unification, when air quality improved. In this analysis
associations between all-cause mortality and UFPs and PM2.5 were analyzed from September 1995 to
March 2002, while PMi0, NO2 and CO was analyzed for the whole study duration. The exposure
time window / averages used in this study were different from those used by Stolzel (2003, 042842)
and Stolzel et al. (2007, 091374). Breitner et al. (2009, 188439) investigated the cumulative effect of
air pollution on mortality at lags 0-5 and 0-14, using (a) a semiparametric Poisson regression model;
and (b) a third degree polynomial distributed lag (PDL) model. The authors  estimated the mortality
risk for the entire study period as well as specific time periods to examine the effect of declining air
pollution levels on the air pollution-mortality association. Of the air pollutants examined, UFPs were
December 2009
                                               6-190

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found to be most consistently associated with mortality. NO2 and CO were also found to be
significantly associated with mortality using the 15-day PDL and 15-day avg models, respectively.
PM2.5 and PMi0 also showed positive, but much weaker associations with mortality. In this data set,
UFPs were only moderately correlated with PM25 (r = 0.48) and PMi0 (r = 0.57). Of the pollutants
examined, NO2 showed the strongest (but overall a moderate) correlation with UFPs (r = 0.62).
When the risk estimates were compared between the two latter time periods of the study (September
1995-February 1998; and March 1998-March 2002), the estimates obtained using the 6-day avg for
these pollutants generally declined. For example, the all-cause mortality risk estimates associated
with a 8,439/cmyincrease in UFP NC was 5.5% (95%  CI: 1.1-10.5) for the earlier period and -1.1%
(95% CI: -6.8 to 4.9) for the later period. However, such patterns were less clear when using 15-
day avg pollutant concentrations. In summary, UFPs appear to be the pollutant most consistently
associated with mortality in Erfurt, Germany, but combined with the results for NO2 and CO, these
associations may implicate the role of local combustion sources  on the mortality association
observed.
      Kettunen et al.'s (2007, 091242) study in Helsinki also examined the relationship between
UFPs and stroke mortality. As described earlier, PM2 5, PMi0, and CO was associated with stroke
mortality only during the warm season. The association with UFPs was borderline non-significant
(8.5% [95% CI: -1.2 to!9.1] per 4,979/cm3 increase in UFPs at lag 1 day), but its lag structure of
association and the magnitude of the effect estimate per interquartile-range are similar to those for
PM2 5. Note that the UFP NC levels in Helsinki (median equals 8,986/cm  during the cold season and
7,587/cm3 during the warm season) are lower than those in Erfurt (mean = 13,549/cm3), but clearly
higher in the cold season.


      Summary of UFP Risk Estimates

      Only a  few new studies, all of them conducted in Europe,  examined and reported associations
between UFPs and mortality. In Erfurt, UFPs showed the strongest associations  with mortality
among all of the PM indices, but its lag structure of association is either unique with the strongest
association at lag 4 days in Stolzel et al. (2007, 091374). not consistent with the lag structure of
associations found in other mortality studies, or the time-windows examined are longer (0-5 and
0-14 days) ((Breitner et al., 2009, 188439). making it  difficult to compare whether the associations
observed are consistent with those reported in other studies. In Helsinki, the association between
UFPs and stroke mortality was weaker than that for PM2 5, but its lag structure of association was
similar to that for PM2 5 (strongest at lag 1 day). However, Kettunen et al. (2007, 091242) only
examined lags 0-3 days.  Overall, the results of these studies should be viewed with caution because
UFPs were consistently found to be correlated with gaseous pollutants derived from local
combustion sources, and one or more of the gaseous pollutants were also  found to be associated with
mortality. Clearly, more research is needed to further investigate the role of UFPs on PM-mortality
associations.


6.5.2.5.   Chemical Components of PM

      A few recent studies have  examined the association between mortality and components of
PM25. This endeavor has been undertaken by some investigators through  the use of the newly
available PM2 5 chemical speciation network data. The PM2 5 chemical speciation network consists of
more than 250 monitors that have been collecting over 40 chemical species since 2000; however,
most sites started collecting data in 2001. One caveat to the new network  is that because the
sampling frequencies of the monitors are either every third day or every sixth day, there have not
been, generally, a sufficient number of days to examine associations with  mortality in single cities.
To circumvent this issue, some investigators (Bell et al., 2009, 191997; Dominici et al., 2007,
099135: Franklin et al., 2008, 097426: Lippmann et al., 2006, 091165) have used the PM2.5
chemical species data in a second stage regression to explain the heterogeneity in PMi0 or PM2 5
mortality risk estimates across cities. However, it should be noted these studies assume that the
relative contributions of PM2 5 have remained the same over time. There have also been some studies
that directly analyzed speciated PM25 data (e.g., Klemm et al., 2004, 056585; Ostro et al., 2007,
091354).
December 2009                                 6-191

-------
      Explaining the Heterogeneity of PM10 Risk Estimates Using PM2.5 Chemical
      Speciation Data

      Lippmann et al. (2006, 091165). in addition to their primary analysis1, investigated the
consistency of the associations between specific elements and health outcomes by examining the
heterogeneity of published 1-day lagged NMMAPS PMi0 mortality risk estimates for 1987-1994
across cities as a function of the average PM2.5 chemical components across cities. They matched
PM2.5 chemical species  in 60 out of 90 cities. Lippmann et al. (2006, 091165) noted that the
concentrations of the 16 chemical species examined averaged over the years 2000-2003 were highly
skewed across cities. They therefore regressed PMi0 risk estimates on each of the PM2.5 components,
raw and log-transformed, with weights based on the standard error of the PMi0 risk estimates. The
log-transformed values  yielded better predictive power, and the authors subsequently presented the
results with log-transformed values. As shown in Figure 6-31, the 16 PM2.5 species showed varying
extent of predictive power in explaining the PM10 risk estimates across 60 cities, with Ni and V
being the best predictors.


EC


Cu

OC
PM






























0









"




                                      -0.5     0.0     0.5     1.0
                                    Percent per 10-jit(/ni3 increase in PM10
                                                                        Source: Lippmann et al. (2006, 091165)
Figure 6-31.   Percent increase in PMio risk estimates (point estimates and 95% CIs) associated
              with a 5th-95th percentile increase in PM2.s and PM2.5 chemical components.  The
              PM2.6 chemical components were log-transformed in the regression. The PMio
              risk estimates were for 60 NMMAP cities for 1987-1994.

      Dominici et al. (2007, 099135) examined the influence of Ni and V on the updated NMMAPS
PMio mortality risk estimates for 1987-2000,  using 72 counties in which Ni and V data were
collected. A Bayesian hierarchical model was used to estimate the role of Ni and V on the
heterogeneity of PMio risk estimates. While they found both Ni and V to be significant predictors of
variation in PMi0 mortality risk estimates across cities, they also noted that this result was sensitive
to the inclusion of the New York City data. Lippmann et al. (2006, 091165) and Dominici et al.
(2007, 099135) both reported that the Ni levels in New York City are particularly high (-10 times the
national average). Figure 6-32 shows the result of the sensitivity analysis for Ni. Note that the Ni in
this result was not log-transformed, as clearly reflected in the change in the width of confidence
bands when the New York data were removed (i.e., a skewed distribution produces narrow bands).
1 The main focus of the study was to examine the role of PM2.5 chemical components in a mouse model of atherosclerosis (ApoE ')
 exposed to concentrated fine PM (CAPs) in Tuxedo, NY.
December 2009
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-------
Dominici et al. (2007, 099135) further noted that they reached "the same conclusion" when
log-transformed data were used in the analysis, but the results were not presented.
                           No communities removed
                                    •a
                                    0)
                                    o
                                    =
                                    OJ
                                    .&
                                    o
                                    u
                                    I
                                    o
                           New York removed
                                  —i	
                                   -10
                            -20     -10     0      10     20      30

                            Percent increase in PM10 risk estimates per IQR Ni
                                          Source: Reprinted with Permission of Oxford University Press from Dominici et al. (2007, 099135)

Figure 6-32.   Sensitivity of the percent increase in PM™ risk estimates (point estimates and
              95% CIs) associated with an interquartile increase in Ni. The Ni concentration
              was not log-transformed in this regression model. The PM10 risk estimates were
              for 72 NMMAP cities for 1987-2000. The top estimate is achieved by including
              data for all the 69 communities. The other estimates are calculated by excluding
              one of the 69 communities at a time.

      Bell et al. (2009, 191997) presented a supplemental analysis similar to both Lippmann et al.
(2006, 091165) and Dominici et al. (2007, 099135) in their examination of whether the variation in
PM2 5 risks for cardiovascular and respiratory hospital admissions is due to differences in PM2.5
chemical composition. The authors used the 100 U.S. cities included in the Peng et al. (2005,
087463) analysis and PMi0 data for the years 1987-2000 along with PM25 chemical component data
for 2000-2005. Using a Bayesian hierarchical model, Bell et al. (2009, 191997) found that PMi0
relative risks for total mortality were greater in counties and during seasons with higher PM2.5 Ni
concentrations. However, in a sensitivity analysis when selectively removing cities from the overall
estimate, the significant association between the PMi0 mortality risk estimate and the PM2 5  Ni
fraction was diminished upon removing New York city from the analysis, which is consistent with
the results presented by Dominici et al. (2007, 099135).


      Explaining the Heterogeneity of PM2.5 Risk Estimates Using PM2.5 Chemical
      Speciation  Data

      The first stage of the Franklin et al. (2008, 097426) 25 cities study, described previously,
focused on a time-series regression of mortality on PM2 5 by season. In the second stage random
effects meta regression, the PM25 mortality risk estimates (25 cities><4 seasons = 100 estimates) were
regressed on the ratio of mean seasonal PM25 species to the total PM25 mass. The authors included
those species that had at least 25% of the reported concentrations above the minimum detection
limit, which resulted in 18 species being included in the analysis. Their rationale for using species
proportions as effect modifiers, according to the investigators, was that "in the first stage of the
analysis the mortality risk was estimated per unit of the total PM25 mass, which encompassed all
December 2009
6-193

-------
measured species, and therefore it would not be meaningful to use the species concentrations directly
as the effect modifier" (Franklin  et al., 2008, 097426). In the second stage regression model,
Franklin et al. (2008, 097426) also included a quadratic function of seasonally averaged temperature
to capture the inverted U-shape relationship between PM2.5 penetration and temperature. They found
that the fitted relationship between PM2.5 risk estimates across cities and seasonally averaged
temperature substantiates the use of temperature as a surrogate for ventilation (Franklin et al., 2008,
097426). Table 6-17 shows the resulting effect  modification by PM25 species. Al, As, Ni, Si, and
SO4 ~ were found to be significant effect modifiers of PM2.5 risk estimates, and simultaneously
including Al, Ni, and SO4 ~ together, or Al, Ni,  and As together further increased explanatory power.
Of all the species examined, Al and Ni explained the most residual heterogeneity. Franklin et al.
(2008, 097426) also examined the effect of demographic variables on PM2 5 risk estimates and found
that only median household income was significantly associated with mortality.


Table 6-17.   Effect modification of composition on the estimated percent increase in mortality with a
             10 [jg/rn3 increase in PM2.6.
Cause








Nonaccidental
Univariate








Nonaccidental
Multivariate
(1)
Nonaccidental
Multivariate
(2)
p-value for effect % increase in nonaccidental mortality per 10 ug/m3 Heteroaeneitv
Species modification by species to increase in PIV^.s for an interquartile increase in exnlained f°/ v
PM2.s mass proportion species to PM2.s mass proportion* expiamea (/<>)
Al
As
Br
Cr
EC
Fe
K
Mn
Na+
Ni
N03
NrV
OC
Pb
Si
S042"
V
Zn
Al
Ni
S042"
Al
Ni
As
<0.001
0.02
0.11
0.12
0.79
0.43
0.10
0.42
0.22
0.01
0.07
0.84
0.59
0.31
0.03
0.01
0.28
0.19
<0.001
0.01
<0.001
<0.001
0.01
<0.001
0.58
0.55
0.38
0.33
0.06
0.12
0.41
0.14
0.20
0.37
-0.49
0.04
-0.02
0.17
0.41
0.51
0.30
0.23
0.79
0.34
0.75
0.61
0.35
0.58
45
35
5
16
0
3
28
10
14
41
28
3
4
11
25
33
3
15

100

100
*Adjusted for temperature
Includes heterogeneity explained by temperature
                                         Source: Reprinted with Permission of Lippincott Williams & Wilkins from Franklin et al. (2008, 09742'
      Although Lippmann et al. (2006, 091165) used NMMAPS PM19 risk estimates and Franklin
et al. (2008, 097426) used PM2 5 risk estimates to examine effect modification due to various PM
December 2009
6-194

-------
species, 14 out of the 18 species analyzed in these two studies overlap (Figure 6-31 and Table 6-17).
Both studies found that Ni explained the heterogeneity in PM risk estimates. Note that New York
City was not included in the 25 cities examined in Franklin et al. (2008, 097426) and, thus, could not
influence the result. Sulfate positively, but not significantly, explained the PMi0 risk estimates in the
Lippmann et al. (2006,  091165) analysis. However, SO42~ was a significant predictor of PM2.5 risk
estimates in the Franklin et al. (2008, 097426) analysis. Al and Si were negative (i.e., less than the
average PM10 risk estimates across cities), though not significant predictors in the Lippmann et al.
(2006, 091165) analysis. Unlike the Franklin et al. (2008, 097426) analysis, arsenic (As) showed no
association with mortality in the Lippmann et al. (2006, 091165) analysis. The source of these
differences may be due to the difference in geographic coverage, PM size (PM2 5 may represent more
secondary aerosols than PMi0), or the difference in the analytical methods used  in each study.
Specifically, the analytical approach used by Franklin et al. (2008, 097426) does have an advantage
of delineating seasonal  variations in PM components and the associated potential seasonal mortality
effects.
      In light of the results presented in speciation studies it must be noted  that  second stage
analyses that use PM chemical species as effect modifiers have some limitations. Unlike analyses
that directly examine the associations between chemical species and mortality, if an effect
modification is observed it may be confounded if the variations of the mean levels of the chemical
species examined are correlated with other demographic factors that vary across cities. Thus, more
concrete conclusions could be formulated if direct associations are found between mortality and PM
chemical components in time-series analyses.


      Association between PM2.s Chemical Components and Mortality

      Ostro et al. (2007, 091354) examined associations between PM2.5 chemical components and
mortality in six California counties (Fresno, Kern, Riverside, Sacramento, San Diego, and Santa
Clara), which had at least 180 days of speciation data for the years 2000-2003. The study examined
all-cause, cardiovascular, and respiratory mortality for individual lags of 19 specific PM25 chemical
components. The second stage random-effects model combined risk estimates at each lag across
cities. The number of available days for chemical species data ranged from 243  (San Diego  County)
to 395 (Sacramento County). The authors found an association between mortality, especially
cardiovascular mortality, and several chemical components. For example, cardiovascular mortality
was associated with EC, OC, nitrate, Fe, K, and Ti at various lags.
      Even though this was a multicity study, the relatively small number of available days  and the
every-third-day (or every-sixth-day) sampling frequency for PM2 5 chemical species made it difficult
to interpret the results of the lag structure of associations observed for the chemical species. To
evaluate the impact of non-daily sampling frequency, Ostro et al. (2007, 091354) examined  both the
PM2 5 series that coincides with the speciation sampling days (for the initial six  counties
[i.e., PM25c]) and PM25 data that was available on all days for an extended set of counties (the initial
six counties plus Contra Costa, Los Angeles, and Orange Counties [i.e., PM25ext]). Figure 6-33 shows
the association between all-cause mortality and selected PM2 5 chemical species as well as for PM2 5c
and PM2 5ext. Note the wide confidence bands for the risk estimates for each PM2 5 chemical  species
and PM25c, apparently reflecting the low statistical power of the data. The lag structure of
associations is more clearly defined for PM2 5ext, and appears to be different from that for PM2 5.
December 2009                                 6-195

-------
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Species and lag day
                                                                          Source: Ostro et al. (2007, 091354)
Figure 6-33.
              Percent excess risk (Cl) of total (nonaccidental) mortality per IQR of
              concentrations. Note: PM2.6 has the same sampling days as chemical species.
              PM2.6 has all available PM2.6ext data for nine counties. * p < 0.10; ** p < 0.05
      Ostro et al. (2008, 097971) used the speciation data from the six counties analyzed in their
2007 analysis, described above, in an additional analysis to examine effect modification of
cardiovascular mortality effects, which showed the strongest association in the 2007 analysis,
attributed to PM2.5 and 13 chemical components by socio-economic and demographic factors. The
results of the analysis were combined using random effects meta-analysis. The investigators tested
statistical differences in risk estimates between strata using a t-test, and reported that, for many of the
PM2.5 chemical species; there were significantly higher effect estimates among those with lower
educational attainment and Hispanics. While these patterns were apparent in their results table,
interpretation of the results is not straightforward because the table only presented the most
significant  (and positive) lags, and they were often different between the strata (e.g., the most
frequent significant lag for the Hispanic group was 1 day, while it was 2 or 3 days for the White
group). As  the investigators pointed out, the every -third-day sampling frequency of the speciation
data also complicates the interpretation of the results for different lags.
      Overall, the two studies by Ostro et al. (2007, 091354) were the first attempt to directly
analyze associations between the newly available chemical speciation data and mortality. While
suggestive  associations between several chemical species and mortality were reported, a longer
length of observations is needed to more clearly determine the  associations.


6.5.2.6.   Source-Apportioned PM Analyses

      Chemically speciated PM data allow for the source apportionment of PM.  The idea of using
source-apportioned PM for health effects analyses is appealing because, if such
source-apportionment could be reliably conducted, it would allow for an evaluation of PM2.5 mass
concentrations by source types. However, the uncertainties associated with source-apportionment
methods have not been well characterized.
      To address this issue, in 2003, several groups  of EPA-funded researchers organized a
workshop and independently conducted source apportionment on two sets of data: Phoenix, AZ, and
Washington, DC, compared the results (Hopke et al., 2006, 088390). and then conducted time-series
December 2009
                                            6-196

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mortality regression analyses using each group's source-apportioned data (Ito  et al., 2006, 088391;
Mar et al., 2006, 086143; Thurston  et al., 2005, 097949). The various research groups generally
identified the same major source types, each with similar elemental compositions. Inter-group
correlation analyses indicated that soil-, SO42~-, residual oil-, and salt-associated mass concentrations
were most unambiguously identified by various methods, whereas vegetative burning and traffic
were less consistent. Aggregate source-specific mortality relative risk (RR) estimate confidence
intervals overlapped each other, but  the SO42~-related PM2 5 component was most consistently
significant across analyses in these cities.
      The results from the source-apportionment workshop quantitatively characterized the
uncertainties associated with the factor analysis-based methods,  but they also raised new issues. The
mortality analyses conducted in Phoenix, AZ, and Washington, DC, both found that different
source-types showed varying lag structure of associations with mortality. For example, Figure 6-34
shows cardiovascular mortality risk  estimates for three of the PM2.5 sources from the Phoenix, AZ,
analysis (Mar  et al., 2006, 086143). The strongest associations for "traffic" PM2.5 was found for lag
1-day, while for "secondary  SO4 ~" PM25, it was lag 0, with a monotonic decline towards longer
lags. These results are consistent with those in the 2004 PM AQCD (U.S. EPA, 2004,  056905). in
which associations were reported with combustion-related PM2 5, but not crustal source PM2 5. It is
conceivable that PM from different source types produces different lagged effects, but it is also
likely that different PM species have varying lagged correlations with the covariates in the health
effects regression models (e.g., temperature, day-of-week) resulting in apparent differences in lagged
associations with mortality. Thus, interpretation of these source-apportioned PM health effect
estimates remains challenging.
  1.4-
  1.?
  1.0
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                                1.4-
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                             Secondary sulfate
       ABCDEFGH
                                     ABCOtf-GH
                                                                    A   B  C  D  t  F  G
                                            Source: Reprinted with Permission of Nature Publishing Group from Mar et al. (2006, 0861431
Figure 6-34.    Relative risk and Cl of cardiovascular mortality associated with estimated PM2.s
               source contributions. Y-axis: relative risk per 5th-to-95th percentile increment of
               estimated PM2.s source contribution.  X-axis: the alphabet denotes investigator/
               method; lagged PM2.6 source contribution for lag 0 through 5 days, left to right,
               are shown for each investigator/method.
6.5.2.7.   Investigation of Concentration-Response Relationship
      The results from large multicity studies reviewed in the 2004 PM AQCD (U.S. EPA, 2004,
056905) suggested that strong evidence did not exist for a clear threshold for PM mortality effects.
However, as discussed in the 2004 PM AQCD (U.S. EPA, 2004, 056905). there are several
challenges in determining and interpreting the shape of PM-mortality concentration-response
functions and the presence of a threshold, including: (1) limited range of available  concentration
levels (i.e., sparse data at the low and high end); (2) heterogeneity of susceptible populations; and (3)
December 2009
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the influence of measurement error. Regardless of these limitations, studies have continued to
investigate the PM-mortality concentration-response relationship.
      Daniels et al. (2004, 087343) evaluated three concentration-response models: (1) log-linear
models (i.e., the most commonly used approach, from which the majority of risk estimates are
derived); (2) spline models that allow data to fit possibly non-linear relationship; and (3) threshold
models, using PMi0 data in 20 cities from the  1987-1994 NMMAPS data. They reported that the
spline model, combined across the cities, showed a linear relation without indicating a threshold for
the relative risks of death for all-causes and for cardiovascular-respiratory causes in relation to PMi0,
but "the other cause" deaths (i.e., all cause minus cardiovascular-respiratory) showed an apparent
threshold at around 50 ug/m3 PMi0, as shown  in Figure 6-35. For all-cause and cardio-respiratory
deaths, based on the Akaike's Information  Criterion (AIC), a log-linear model  without threshold was
preferred to the threshold model and to the spline model.
      The HEI review committee commented that interpretation of these results required caution,
because (1) the measurement error could obscure any threshold; (2) the city-specific concentration-
response curves exhibited a variety of shapes; and (3) the use of AIC to choose among the models
might not be appropriate due to the fact it was not designed to assess scientific theories of etiology.
Note, however, that there has been no etiologically  credible reason suggested thus far to choose one
model over others for aggregate outcomes. Thus, at least statistically, the result of Daniels et al.
(2004, 087343) suggests that the log-linear model is appropriate in describing the relationship
between PMi0 and mortality.
             Total Mortality                       CVDRESP Mortality               Other Cause Mortality
   o
   Ł
   "es
   CC
                                                PM  (MQ/m3)
                                                     Source: Reprinted with Permission of HEI from Daniels et al. (2004, 087343)

Figure 6-35.   Concentration-response curves (spline model) for all-cause, cardiovascular,
              respiratory and other cause mortality from the 20 NMMAPS cities. Estimates are
              posterior means under Bayesian random effects model. Solid line is mean  lag,
              triangles are lag 0 (current day), and squares are lag 1 (previous day).

      The Schwartz (2004, 078998) analysis of PMi0 and mortality in 14 U.S. cities, described in
Section 6.5.2.1, also examined the shape of the concentration-response relationship  by including
indicator variables for days when concentrations were between 15 and 25 (ig/m3, between 25 and
34 (ig/m3, between 35 and 44 (ig/m3, and 45 (ig/m3 and above. In the model, days with
concentrations below 15 (ig/m3 served as the reference level. This model was fit using the single
stage method, combining strata across all cities in the case-crossover design. Figure 6-36 shows the
resulting relationship, which does not provide sufficient evidence to suggest that a threshold exists.
The authors did not examine city -to-city variation in the concentration-response relationship in this
study.
December 2009                                  6-198

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2.5
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10 20 30 40 50 60
                                          PM10 (ng/rn3)

                                                   Source: Reprinted with Permission of BMJ Group from Schwartz (2004, 0789981

Figure 6-36.   Percent increase in the risk of death on days with PM10 concentrations in the
              ranges of 15-24, 25-34, 35-44, and 45 ug/m  and greater, compared to a reference
              of days when concentrations were below 15 ug/m3.  Risk is plotted against the
              mean PM10 concentration within each  category.

      Samoli et al. (2005, 087436) investigated the concentration-response relationship between
PM10 and mortality in 22 European cities (and BS in 15 of the cities) participating in the APHEA
project. In nine of the 22 cities, PMi0 levels were estimated using a regression model relating co-
located PMi0 to BS or TSP They used  regression spline models with two knots (30 and 50 (ig/m3)
and then  combined the individual city estimates of the splines across cities. The investigators
concluded that the association between PM and mortality in these cities could be adequately
estimated using the log-linear model. However, in an ancillary analysis of the  concentration-response
curves for the largest cities in each of the three distinct  geographic areas  (western, southern, and
eastern European cities): London, England; Athens, Greece; and Cracow, Poland, Samoli et al.
(2005, 087436) observed a difference in the shape of the concentration-response curve across cities.
Thus, while the combined curves (Figure 6-37) appear  to support no-threshold relationships between
PMio and mortality, the heterogeneity of the shapes across cities makes it difficult to  interpret the
biological relevance of the shape of the combined curves.
December 2009
6-199

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Figure 6-37.   Combined concentration-response curves (spline model) for all-cause,
              cardiovascular, and respiratory mortality from the 22 APHEA cities.

      The results from the three multicity studies discussed above support no-threshold log-linear
models, but issues such as the possible influence of exposure error and heterogeneity of shapes
across cities remain to be resolved. Also, given the pattern of seasonal and regional differences in
PM risk estimates depicted in recent multicity study results (e.g., Peng et al., 2005, 087463). the
very concept of a concentration-response relationship estimated across cities and for all-year data
may not be very  informative.


6.5.3.   Summary and Causal Determinations
6.5.3.1.   PM2.5

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) found that the strength of evidence from U.S.-
and Canadian-based studies (both multi- and single-city) for PM2.5 mortality associations varied
across outcomes, with relatively stronger evidence for associations with cardiovascular compared to
respiratory causes. The resulting effect estimates reported for these two endpoints ranged from 1.2 to
2.7% for cardiovascular-related mortality and 0.8 to 2.7% for respiratory-related mortality, per
10 (ig/m3 increase in PM2.5 (U.S. EPA, 2004, 056905).
      In the current review, PM2.5 risk estimates were found to be consistently positive, and slightly
larger than those reported for PM10 for all-cause, and respiratory- and cardiovascular-related
mortality. The risk estimates for all-cause (nonaccidental) mortality ranged from 0.29% (Dominici
et al., 2007,  097361) to 1.21% (Franklin et al., 2007,  091257)  per 10 (ig/m3 increase in PM2.5. These
associations were consistently observed at lag 1 and lag 0-1, which have been confirmed through
extensive analyses in PMi0-mortality studies. Cardiovascular-related mortality risk estimates were
found to be similar to those for all-cause mortality; whereas, the risk estimates for respiratory-related
mortality were consistently larger: 1.01% (Franklin et al., 2007, 091257) to 2.2% (Ostro et al.,
2006, 087991) using the same lag (i.e., lag 1 and lag 0-1) and averaging indices. The studies
evaluated that examined the relationship between short-term exposure to PM2 5 and cardiovascular
December 2009
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effects (section 6.2) provide coherence and biological plausibility for PM2.5-induced cardiovascular
mortality, which represents the largest component of total (nonaccidental) mortality (~ 35%)
(American Heart Association, 2009, 198920). However, as noted in section 6.3, there is limited
coherence between some of the respiratory morbidity findings from epidemiologic and controlled
human exposure studies for the specific health outcomes reported and the subpopulations in which
those health outcomes occur, complicating the interpretation of the PM25 respiratory mortality
effects observed.
      Regional and seasonal  patterns in PM2 5 risk estimates were observed with results  similar to
those presented for PMio (Dominici et al.. 2007. 097361; Peng  et al., 2005, 087463; Zeka etal,
2006, 088749). with the greatest effects occurring in the eastern U.S. (Franklin  et al., 2007, 091257;
Franklin et al., 2008, 097426) and during the spring (Franklin  et al.. 2007. 091257; Zanobetti  and
Schwartz, 2009, 188462). Of the studies evaluated only Burnett et al. (2004, 086247). a Canadian
multicity study, analyzed gaseous pollutants and found mixed results, with possible confounding of
PM2.5 risk estimates by NO2.  Although the recently evaluated U.S.-based multicity studies did not
analyze potential confounding of PM25 risk estimates by gaseous pollutants, evidence from single-
city studies evaluated in the 2004 PM AQCD (U.S. EPA, 2004, 056905) suggest that gaseous
copollutants do not confound the PM2 5-mortality association, which is further supported by studies
that examined the PMi0-mortality relationship. An examination of effect modifiers (e.g.,
demographic and socioeconomic factors), specifically AC use which is sometimes used as a
surrogate for decreased pollutant penetration indoors, has suggested that PM2 5 risk estimates
increase as the percent of the population with access to AC decreases (Franklin  et al., 2007, 091257;
2008, 097426). Collectively,  the epidemiologic evidence is sufficient to conclude that 3 C3US3I
relationship exists between short-term exposure to PM   and mortality.


6.5.3.2.  PM10.2.5

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) found a limited  body of evidence that was
suggestive of associations between  short-term exposure to ambient PM10_2.5 and various mortality
outcomes (e.g., 0.08 to 2.4%  increase in total [nonaccidental] mortality per 10 ug/m3 increase in
PMio_2.5). As a result, the AQCD concluded that PMi0_2.5, or some constituent component(s)
(including those on the surface) of PMi0_2.5, may contribute, in certain circumstances, to increased
human health risks.
      The majority of studies evaluated in this review that examined the relationship between
PMio_2.5 and mortality reported consistent positive associations in areas with mean 24-h avg
concentrations ranging from  6.1-16.4 ug/m3. However, uncertainty surrounds the PMi0_2.5
associations reported due to the different methods used to estimate PMi0_2.5 concentrations across
studies (e.g., direct measurement of PMi0_2.5 using dichotomous  samplers, calculating the difference
between PMi0 and PM2 5 concentrations).
      Anew study of 47 U.S. cities (Zanobetti  and  Schwartz, 2009, 188462). which estimated
PM10_2.5 by calculating the difference between the county-average PM10 and PM2 5, found
associations between PMi0_2.5 and mortality across the U.S., including regions where PMi0_2.5 levels
are not high. In addition, one well conducted multicity Canadian study (Burnett  et al., 2004,
086247) provided evidence for an association between short-term exposure to PMi0_2.5 and mortality.
However, unlike PM25 very few of  the PMi0_2.5 studies have investigated confounding by gaseous
copollutants or the influence  of model specification  on PMi0_2.5 risk estimates. Zanobetti and
Schwartz (2009, 188462) did provide preliminary evidence for greater  effects occurring during the
warmer months (i.e., spring and summer), which is consistent with the  results from PMi0-mortality
studies (Peng  et al., 2005, 087463;  Zeka  et al., 2006, 088749). Overall, although more data is
needed to: adequately characterize the chemical and biological components that may modify the
potential toxicity of PMi0_2.5 and compare  the different methods used to estimate exposure, consistent
positive associations between short-term exposure to PMi0_2.5 and mortality were observed in the
U.S. and Canadian-based multicity  studies evaluated, as well as  the single-city studies conducted in
these locations. Therefore, the epidemiologic evidence JS Suggestive  Of 3 C3US3I relationship
between short-term exposure to PM1025 and  mortality.
December 2009                                 6-201

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6.5.3.3.   UFPs

      Limited evidence was available during the review of the 2004 PM AQCD (U.S. EPA, 2004,
056905) regarding the potential association between UFPs and mortality. The lone study evaluated
was conducted in Germany and provided some evidence for an association, but this association was
reduced upon the inclusion of gaseous pollutants in a two-pollutant model.
      Only a few new studies, all of them from Europe, were identified during this review, which
examined the association between short-term exposure to UFPs and mortality. Inconsistencies were
observed in the lag structure of association reported by each study in terms of both the lag day with
the greatest association and the number of lag days considered in the study. Overall the studies
consistently found that UFPs were correlated with gaseous pollutants derived from local combustion
sources and that one or more of the gaseous pollutants were  also associated with mortality. The
limited number of studies available and the discrepancy in results between studies further confirms
the need for additional data to examine the UFP-mortality relationship. In conclusion, the
epidemioiogic evidence is inadequate to infer a causal association between short-term
exposure to UFPs and mortality



6.6.  Attribution  of  Ambient PM Health  Effects to Specific

Constituents or Sources

      From a mechanistic perspective, it is highly plausible that the chemical composition of PM
would be a better predictor of health effects than particle size. The observed geographical gradients
in a number of PM2.5 constituents (e.g., EC, OC, nitrate, and SO42^ and regional heterogeneity in
PM-related health effects reported in epidemioiogic studies are consistent with this hypothesis.
Recent studies in epidemiology, controlled human exposure, and toxicology have begun using
information on ambient PM composition, and apportionment of constituents into sources, in an
attempt to identify those with links to health outcomes and endpoints.
      This section focuses on short-term exposure studies that (1) assessed health effects for ambient
PM sources or components; and (2) used quantitative methods to relate those sources and
components to  health effects. Epidemioiogic, controlled human exposure, and toxicological studies
that took into consideration a large set of PM constituents (typically minerals, metals, EC, OC, and
ions such as SO42~) and aimed to segregate which constituents or groups of constituents may be
responsible for the PM-related health effects observed are included. Most of these studies were
reviewed earlier in this chapter and evaluated the relationship between specific chemical constituents
derived from ambient PM and health effects. However, there were many studies presented earlier, as
well as others only included in the Annexes, which only selected one or a small number of PM
constituents a priori. Several controlled human exposure and toxicological studies likewise used a
single compound found in PM rather than ambient PM. Additionally, studies that presented ambient
PM composition and health data without systematically and  explicitly investigating relationships are
not included in this section. The few epidemioiogic studies of long-term exposure that examined
potential  relationships between composition and sources of PM with mortality are discussed in
Section 7.6.2.
      Prior to the 2004 PM AQCD (U.S. EPA, 2004, 056905). only a handful of epidemioiogic
studies had attempted to relate specific constituents or sources of ambient PM to health outcomes
without selecting constituents a priori. In this review, approximately 40 new epidemioiogic,
controlled human exposure, and toxicological studies explore the health effects attributed to
chemical constituents and sources of ambient PM. The following summary (Section 6.6.3) provides
a synthesis of the findings, including discussions on the coherence and consistency of the results.


6.6.1.   Evaluation Approach

      Relating a large number of ambient PM constituents with a large number of health outcomes
presents difficulties that are related to both the nature of PM and methods of quantitative analysis.
First, the number of constituents that comprise PM is not only large, but the correlations between
them can be high. Reducing the correlation between constituents has been accomplished in most of
December 2009                                 6-202

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the recent studies through various forms of factor analysis, which limits the correlations between
constituents by grouping the most highly correlated ambient PM constituents into less correlated
groups or factors. Some studies identify the resulting groups or factors with named sources of
ambient PM, but many do not draw explicit links between factors and actual sources. The methods
used in estimating source contributions to ambient PM are reviewed in Section 3.6.1.
      Most studies reviewed herein, regardless of discipline, were based on data for between 7 and
20 ambient PM constituents, with EC, OC, SO4s and NO3 most commonly measured. Most studies
first reduced the number of ambient PM constituents by grouping them with various factorization or
source apportionment techniques and the majority labeled the constituent groupings according to
their presumed source. A separate analysis was then used to examine the relationship between the
grouped PM constituents and various health effects. A few performed these two steps simultaneously
using Partial Least Squares  (PLS) procedures or  Structural Equation Modeling (SEM). A small
number of controlled human exposure and toxicological studies did not apply any kind of grouping
to the ambient PM  speciation data.
      There are some differences in the type of PM constituent data used in epidemiologic,
controlled human exposure  and toxicological studies. In epidemiologic studies, ambient PM
speciation data is obtained from atmospheric monitors; for controlled human exposure and
toxicological studies, the technique used in the experimental exposure  determines the type of PM
data. Thus, all  epidemiologic studies relied on monitor data, while all of the controlled human
exposure and the majority of the toxicological studies used CAPs (and analyzed the concentrations
of constituents therein). The remaining toxicological studies used ambient PM samples collected on
filters at various U.S. sites. Further details on the studies included can be found in Appendix F.
      Some important limitations in interpreting these studies together is that few, if any of the
results are easily comparable,  due to:  (1) differences in the sets of ambient PM constituents that
make up  each of the factors; (2) the subjectivity involved in labeling factors as sources; (3) the
numerous potential health effects examined in these studies, including  definitive outcomes (e.g.,
HAs) as well as physiological alterations (e.g., increased inflammatory response); and (4) the various
statistical methods  and analytical approaches used in the studies. There are no well-established,
objective methods for conducting the various forms of factor analysis and source apportionment,
leaving much of the model operation and factor assignment open to judgment by the individual
investigator. For example, the Al/Si factor identified in one study may  differ from the Al/Ca/Fe/Si
factor from another study, and the "Resuspended Soil" factor from a third study. After factorization
or apportionment of the ambient PM data, the methods used for analyzing the potential association
between ambient PM constituents or sources and health effects also varied. Except for the studies
that used PLS or SEM, controlled human exposure and toxicological studies all used univariate
mixed model regression for every identified PM  factor or source. A number of toxicological studies
followed the univariate step with multivariate regression for all factors. Epidemiologic studies
generally related short-term exposure to sources  with health outcomes  through various forms of
Poisson regression.


6.6.2.   Findings

      The results that follow are organized by discipline, with epidemiologic studies followed by
controlled human exposure  and toxicological studies. This section ends with a summary table, Table
6-18. Table 6-18 is broken out by PM2.5 sources,  and includes  those epidemiologic, controlled human
exposure, and in vivo toxicological studies that either grouped ambient PM2.5 constituents or used
tracers for each source. The table does not include all factors or sources examined in the studies
listed: those factors or sources for which no association with effects was found not included.


6.6.2.1.   Epidemiologic  Studies


      Results from the 2004 PM AQCD

      Three epidemiologic studies that examined the association between PM constituents or sources
and specific health effects were evaluated in the 2004 PM AQCD (U.S. EPA, 2004, 056905). Of
December 2009                                 6-203

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these studies, one study associated daily mortality with a mobile sources PM factor in Knoxville, TN
and St. Louis, MO and coal in Boston, MA, while the crustal factor was not found to be significant
for any of the six cities studied (Laden et al, 2000, 012102; Schwartz, 2003, 042811). Another
study demonstrated an association between a regional SO4 ~ factor and total mortality at lag 0 in
Phoenix and factors for regional SO42~, motor vehicles, and vegetative burning with cardiovascular
mortality at lags of 0,  1, and 3, respectively (Mar et al., 2000, 001760: 2003, 042841). Negative
associations were observed between total mortality and regional SO42~ at lag 3, along with local SO2
and soil factors (Mar  et al., 2000, 001760; 2003, 042841). Finally, Tsai et al. (2000, 006251)
identified significant associations between PMi5-derived industrial sources and total daily deaths  in
Newark and Camden,  NJ; SO42~ was also linked to cardiopulmonary deaths in both locations.  Total
mortality and cardiopulmonary deaths were also significantly associated with PM from oil burning in
Camden (2000, 006251).


     Comparative Analyses of Source Apportionment Methods

     Hopke  et al. (2006, 088390) conducted a comparative analysis of source apportionment
techniques  used by investigators at multiple institutions, and subsequently used in epidemiologic
analyses (Ito  et al., 2006, 088391; Mar et al., 2006, 086143). An overarching conclusion of this  set
of analyses, reported in Thurston et al. (2005, 097949). is that variation in the source apportionment
methods was  not a major source of uncertainty in the epidemiologic effect estimates. In the primary
analyses, mortality was associated with secondary SO4  ~ in both Phoenix and Washington D.C.,
although lag times differed (0 and 3, respectively). The SO42~ effect was stronger for total mortality
in Washington D.C. and for cardiovascular mortality in Phoenix (Ito et al., 2006, 088391; Mar et
al., 2006, 086143). In  addition, Ito et al. (2006, 088391) found some evidence for associations with
primary coal  and traffic with total mortality in Washington D.C. (Ito et al., 2006, 088391) while
copper smelter, traffic, and sea salt were associated with cardiovascular mortality in Phoenix at
various lag times (Mar et al., 2006, 086143). In contrast to Phoenix, sea salt and traffic were not
associated with mortality in Washington D.C. (Ito  et al., 2006, 088391). but in both locations no
associations were observed between biomass/wood combustion and mortality (Ito  et al., 2006,
088391; Mar et al., 2006, 086143). In an additional study that compared three source apportionment
methods in Atlanta-PMF, modified CMB, and a single-species tracer approach-found that the
epidemiologic results  were robust to the choice of analytic method (Sarnat et al., 2008, 097972).
There were consistent associations between ED visits for cardiovascular diseases with PM2 5 from
mobile sources (gasoline and diesel) and biomass combustion (primarily prescribed forest burning
and residential wood combustion), whereas PM2 5 from secondary SO42~ was associated with
respiratory  disease ED visits (Sarnat et al., 2008, 097972). Sarnat et al. (2008, 097972) also found
that the primary power plant PM2 5 source identified by the CMB approach was negatively associated
with respiratory ED visits while no association was found for PM2 5 from soil and secondary
nitrates/ammonium nitrate. In these studies, effect estimates based on the different source
apportionment methods were generally in close agreement.


     Source Apportionment Studies

     A study that examined associations with mortality in Santiago, Chile, identified a motor
vehicle source of PM25 as having the greatest association with total and cardiac mortality at lag 1
(Cakmak et al., 2009, 191995). There was effect modification by age, with the total mortality
relative risks  associated with PM2 5 from motor vehicles being greatest for those >85 yr. Soil and
combustion sources were also associated with cardiac mortality. Risk estimates  for respiratory
mortality were the greatest for the motor vehicle source, with combustion and soil source factors  also
demonstrating positive associations for lag 1 (Cakmak  et al., 2009, 191995).
     An epidemiologic study that evaluated respiratory ED visits was conducted in Spokane, WA
and used tracers as indicators of ambient PM25 sources (Schreuder  et al., 2006, 097959). In this
study, only  PM2 5 from vegetative burning (total carbon) was associated with increased respiratory
ED visits for  lag 1, while PM25 indicators for motor vehicles (Zn) and soil (Si) were not associated
with cardiac hospital or respiratory ED visits. Andersen et al. (2007, 093201) conducted a source
apportionment analysis to identify the  sources of ambient PMi0 associated with cardiovascular and
December 2009                                 6-204

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respiratory hospital admissions in older adults and children (ages 5-18) in Copenhagen, including
two-pollutant models with various sources of PMi0. Andersen et al. (2007, 093201) found that
secondary and crustal sources of PMi0 were associated with cardiovascular hospital admissions;
biomass sources were associated with respiratory hospital admissions; and vehicle sources were
associated with asthma hospital admissions.
      Several panel epidemiologic studies have examined the association between PM sources  and
physiological alterations in cardiovascular function. Lanki et al. (2006, 089788) reported positive
associations between PM2.5 from local traffic (measured as absorbance, which is correlated with EC
content) and long-range transported PM2.5 with ST-segment depression in elderly adults in a study
conducted in Helsinki, Finland.  Positive associations with ST-segment depression were also reported
with PM2.5 from crustal and salt sources, but these associations were not statistically significant. In
an additional study, Yue et al. (2007, 097968) found that adult males with coronary artery disease in
Erfurt, Germany, demonstrated changes in repolarization parameters associated with traffic-related
PM2.5, with increased vWF linked to traffic and combustion-generated particles, although the source
apportionment was based solely on particle size distribution. In addition, elevated CRP levels were
associated with all sources of PM25 (soil, local traffic, secondary aerosols from local fuel
combustion, diesel, and secondary aerosols from multiple sources) (Yue et al., 2007, 097968).
Reidiker et al. (2004, 056992). in a study  of young male highway patrol officers, found that the most
significant effects (HRV, supraventricular ectopic beats, hematological markers, vWF) were
associated with a speed-change factor for PM2 5 (2004, 056992). In addition, the authors observed an
association between crustal factor and cardiovascular effects, but no health-related associations with
steel wear or gasoline PM2 5 source factors.
      Two recent studies have examined the associations between ambient PM2 5 sources and
respiratory symptoms and lung function. Positive associations with PM2 5 motor vehicle and road
dust sources were reported for respiratory symptoms and inhaler use in asthmatic children in New
Haven, CT, and negative associations with wheeze or inhaler use for biomass burning at lag 0-2
(Gent et al., 2009, 180399). These positive effects for motor vehicle and road dust sources were
robust to the inclusion of a gaseous copollutant (NO2, CO, SO2, or O3) in the regression model.
Penttinen et al. (2006, 087988) in a study consisting of asthmatic adults living in Helsinki, Finland,
found that decrements in PEF were associated with ambient PM2 5 soil, long-range transport, and
local combustion sources at lags from 0-5 days. In addition, negative associations with asthma
symptoms and medication use were reported for PM2 5 from sea salt and long-range transport sources
(Penttinen et al., 2006, 087988).


      PM  Constituent Studies

      Some studies considered large sets of ambient PM constituents and attempted to identify
which were associated with various health effects, but without grouping them into factors, or
identifying sources. The majority  of these studies focused on health effects associated with short-
term exposure to PM2 5. Peng et al. (2009, 191998) examined the association between PM2 5
constituents (i.e., EC, OC, SO42", NO3", Si, Na,  NH4+) and cardiovascular and respiratory hospital
admissions in 119 U.S. cities. When including each constituent in a multipollutant model, they found
that EC and OC  were robust to the inclusion of the other constituents at lag 0 for cardiovascular and
respiratory hospital admissions, respectively. Although this study did not include analyses to identify
sources of the constituents examined, EC and OC are often attributed to motor vehicle emissions,
particularly diesel engines, and wood burning (Peng  et al., 2009, 191998). Ostro et al. (2007,
091354; 2008, 097971) conducted two studies in six California counties to examine the association
between ambient PM constituents and mortality. In the 2007 analysis, Ostro et  al. (2006, 087991)
found associations between Cu and all-cause mortality; EC, K, and Zn and CVD mortality; and Cu
and Ti and respiratory mortality at lags ranging from 0 to 3 days. Associations during the summer
were only observed between K for both CVD and  respiratory mortality; and Al, Cl, Cu, Pb, Ti, and
Zn and respiratory mortality. Overall, the most consistent associations were observed during the cool
season. In a subsequent analysis, Ostro et al. (2008, 097971) examined the association between
ambient PM constituents and cardiovascular mortality in potentially susceptible subpopulations. The
authors found positive associations between EC, OC, NO3", SO42", K, Cu, Fe, and Zn and
cardiovascular mortality. These  associations were higher in individuals with lower educational
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attainment and of Hispanic ethnicity. In addition, similar to the 2007 analysis, associations were
observed at lags ranging from 0 to 3 days.


      Evaluation of Effect Modification by PM Constituents

      Several studies have conducted secondary analyses to examine whether the variation in
associations between PM2.5 and morbidity and mortality or PMi0 and mortality reflects differences in
PM2.5 constituents. An assumption in these types of analyses, especially when examining the effects
on PMio mortality risk estimates, is that the relative contributions of PM2.5 have remained the same
over time; these studies used PMi0 data for years prior to 2000, while PM2.5 speciation data has only
been routinely collected since about 2000. Bell et al. (2009,  191997) found statistically significant
associations between the county average concentrations of V, Ni, and EC (106 counties) and effect
estimates for both cardiovascular and respiratory hospital admissions with short-term exposure to
PM25. In this  analysis the ambient PM25 constituents that comprised the majority of PM25 total mass
in the study locations were NH4+, EC, OC, NO3", and SO42". Bell et al. (2009, 191997) also
conducted a similar analysis for PMio-mortality risk  estimates and found that only Ni increased the
risk estimate.  However, in a sensitivity analysis, when selectively dropping out the communities
examined one at a time, removing New York City diminished the Ni association. Both Lippmann
et al. (2006, 091165) and Dominici et al. (2007, 099135) conducted similar analyses, albeit using a
smaller subset of cities and/or different years of PMi0 data. In both studies, Ni and V were found to
modify the PMi0-mortality risk estimates. Similar to  Bell et al. (2009, 191997). Dominici et al.
(2007, 099135) also found that excluding New York  City as part of a sensitivity analysis resulted in a
diminished association with Ni and V. In an additional study, Franklin et al. (2008, 097426)
examined the potential modification of the PM2 5-mortality relationship by PM constituents in 25
U.S. cities. In a second-stage analysis using the species-to-PM25 mass proportion of multiple
constituents, the authors found that Al, As, Ni,  Si, and SO42" significantly modified the association
between PM2 5 and nonaccidental mortality.


6.6.2.2.  Controlled Human Exposure Studies

      A few controlled human exposure studies employed PCA, although not all linked groupings of
PM constituents to the measured physiological parameters. Huang et al. (2003, 087377)
demonstrated associations between increased fibrinogen and Cu/Zn/V and increased BALF
neutrophils and Fe/Se/SO4 in young, healthy adults exposed to RTP, NC CAPs; however, only water-
soluble constituents were  analyzed. In the other study that examined physiological cardiovascular
effects, Fe and EC were associated with changes in ST-segment, while SO42~ was associated with
decreased SBP in asthmatic and healthy human volunteers exposed to Los Angeles CAPs (2003,
087377).  In Gong et al. (2003, 087365) the majority  of the PM was in the thoracic coarse fraction. In
the other  study that used Los Angeles CAPs, the only observed association was between SO42~
content and decreased lung function (FEVi and FVC) in elderly volunteers with and without COPD
(Gong et al.,  2005, 087921). Two additional controlled human exposure studies that did not perform
grouping and  employed Toronto CAPs plus O3 demonstrated increased DBP and increased brachial
artery vasoconstriction associated with carbon content (Urch et al., 2004, 055629; 2005, 081080).


6.6.2.3.  lexicological Studies

      The only toxicological in vivo study that characterized PM sources  corresponding to identified
sources was conducted in Tuxedo, NY, over a 5-mo period. This study reported that all sources
(regional SO42~, resuspended soil, residual oil, traffic and other unknown sources) were linked to HR
or HRV changes in mice at one time or another during or after daily exposure (Lippmann et al.,
2005, 087453). In a simultaneous in vitro study using CAPs from the same location, NF-KB in
BEAS-2B cells were correlated with the oil combustion factor (r =  0.289 and 0.302 for V and Ni,
respectively) (Maciejczyk and Chen, 2005, 087456). The  other in vitro toxicological study (Duvall
et al., 2008, 097969) that named sources employed samples  from 5 U.S. cities and found a good fit
for the regression model with increased IL-8 release  in primary human airway epithelium cells and
coal combustion (R2= 0.79), secondary nitrate  (R2=  0.63), and mobile sources (R2= 0.39). In
addition,  soil  (R2= 0.48),  residual oil combustion (R2= 0.38), and wood combustion (R2= 0.33) were
December 2009                                 6-206

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associated with COX-2 effects; whereas, secondary SO42  (R2= 0.51) was correlated with HO-1.
Wood combustion and soil were negatively associated with HO-1.
      Several toxicological studies employed Boston CAPs and identified at least four groupings of
ambient PM2 5 constituents (V/Ni, S, Al/Si, and Br/Pb), but they named sources only partially and
tentatively (Batalha et al., 2002, 088109: Clarke et al, 2000, 011806: Godleski et al., 2002,
156478: Nikolov et al., 2008,  156808: Saldiva  et al., 2002, 025988: Wellenius et al., 2003,
055691). When examining cardiovascular effects these studies reported that Si was associated with
changes in the ST-segment of dogs (Wellenius et al., 2003, 055691) and decreased L/W ratio in rat
pulmonary arteries (Batalha et al., 2002, 088109) in multivariate analyses. In addition, blood
hematological results were associated with V/Ni, Al/Si, Na/Cl, and S in dogs (Clarke  et al., 2000,
011806). An examination of respiratory effects in the latter study  found that V/Ni and Br/Pb were
associated with increased inflammation in BALF for only the third day of exposure (Clarke et al.,
2000, 011806). Decreased respiratory rate and increased airway irritation (Penh) in dogs were
associated with road dust (Al)  and motor vehicles  (OC), respectively (Nikolov  et al., 2008, 156808).
Individual PM2 5 constituents associated with elevated neutrophils in BALF were Br, EC, OC, Pb,
and SO42~ (Godleski  et al., 2002, 156478). which  is consistent with the findings (Br, EC, OC, Pb, V,
and Cl) of Saldiva et al. (2002, 0259881
      The two toxicological studies that used PLS methodologies identified PM25  constituents
linked to respiratory parameters.  Seagrave et al. (2006, 091291) demonstrated associations between
cytotoxic responses and a gasoline plus nitrates source factor (OC, Pb, hopanes/steranes, nitrate, and
As) along with inflammatory responses and a gasoline plus diesel source factor (including major
metal oxides) in rats exposed via IT instillation. In the other study, Veranth et al. (2006, 087479)
collected loose surface soil from 28 sites in the Western U.S. and exposed BEAS-2B cells to PM2.5.
OCi, OC3, OC2, EC2, Br, ECi,  and Ni correlated with IL-8 release, decreased IL-6 release, and
decreased viability at low and high doses  (10 and 80 ug/cm2, respectively).
Table 6-18.   Study-specific PM2.6 factor/source categories associated with health effects.
Source Category Location
Health Effects
Time study*1 sPecies Reference
CRUSTAUSOIUROAD DUST
Al, Si, Fe
Not provided
Al, Ca, Fe, Si
Al, Si, Ca, K, Fe
Al, Si, Ca, K, Fe
Al, Si
Al, Si, Ca
Al, Si, Ti, Fe
Al, Si, Ca, Fe
Al, Si
Phoenix, AZ
Washington,
D.C.
Santiago, Chile
Helsinki, Finland
Los Angeles, CA
Boston, MA
Boston, MA
VMe County,
NC
Tuxedo, NY
Boston, MA
nega^ssociationwith
tCV mortality
tCV mortality
t respiratory mortality
ST-segment depression
I ST-segment voltage
ST-segment change
I lumen/wall ratio
t uric acid
t mean cycle length
|HR
tHR
tSDNN, tRMSSD
t blood PMN %
1 blood lymphocytes %
tWBC
Lag 2 E
Lag 4 E
Lag1 E
Lag3 E
2 days post-exposure H
Following exposure T
24 h post-exposure T
Lag 15 h E
During exposure
Afternoon post-exposur
e. Night post-exposure
Following exposure T
Human
Human
Human
Human
Human
Dog
Rat
Human
Mouse
Dog
Mar etal. (2000, 0017601
ltoetal.(2006, 0883911
Cakmak etal. (2009, 1919951
Lanki et al. (2006, 089788)
Gong et al. (2003, 0421061
Wellenius etal. (2003, 0556911
Batalha et al. (2002, 088109)
Riedikeretal. (2004, 0569921
Lippmann et al. (2005, 0874531
Clarke etal. (2000, 0118061
Si, Fe, Al, Ca, Ba, Ti  New Haven, CT
t respiratory symptoms and
inhaler use
Lag 0-2
Human    Gent et al. (2009,1803991
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Source Category
Si, Al, Ca, Fe, Mn
Al
Location
Helsinki, Finland
Boston, MA
Health Effects
I mean PEF
I airway irritation (penh)
Time
Lag3
During exposure
Type of
Study1
E
T
Species
Human
Dog
Reference
Penttinen et al. (2006, 087988)
Nikolov et al. (2008, 156808)
SALT
Not provided
Na, Cl
Na, Cl
Na, Cl
Na, Cl
SECONDARY S042'
S
Not provided
Not provided
S, K, Zn, Pb
S042"
S, Si, OC
S
S042", NH4*, OC
S, K, Zn, PM mass
S042" (+N02)
Phoenix, AZ
Helsinki, Finland
Boston, MA
Helsinki, Finland
Boston, MA
tCV mortality
ftotal mortality
negative association with
total mortality
ST-segment depression
t blood lymphocyte %
Negatively associated with
bronchodilator use and
corticosteroid use
t lung PMN density
Lag5
LagO
Lag3
Following exposure
Lag 0-5 avg
24 h post-exposure
E
E
T
E
T
Human
Human
Dog
Human
Rat
Mar etal. (2006,086143)
Lanki et al. (2006, 089788)

Clarke etal.(2000, 011806)
Penttinen et al. (2006, 0879881
Saldiva et al. (2002, 025988)
/LONG-RANGE TRANSPORT
Phoenix, AZ
Washington,
D.C.
Phoenix, AZ
Helsinki, Finland
Los Angeles, CA
Tuxedo, NY
Boston, MA
Atlanta, GA
Helsinki, Finland
Los Angeles, CA
t total mortality
negative association with
total mortality
t total mortality
tCV mortality
ST-segment depression
|SBP
|HR
|SDNN, IRMSSD
|RBC
t hemoglobin
t respiratory ED visits
1 mean PEF. Negative
association with asthma
symptom prevalence
|FEV,
|FVC
LagO
Lag5
LagS
LagO
Lag 2
4 h post-exposure
Afternoon post-
exposure
Night post-exposure
Following exposure
LagO
Lag1
LagS
Following exposure
E
E
E
E
H
T
T
E
E
H
Human
Human
Human
Human
Human
Mouse
Dog
Human
Human
Human
Mar etal. (2000, 0017601
Ito et al. (2006, 0883911
Mar etal. (2006, 0861431
Lanki et al. (2006, 089788)

Gong et al. (2003, 042106)
Lippmann et al. (2005, 0874531
Clarke et al. (2000, 0118061
Sarnat et al. (2008, 0979721
Penttinen et al. (2006, 0879881
Gong et al. (2005, 0879211
TRAFFIC
Pb, Br, Cu
Not provided
Mn, Fe, Zn, Pb, OC,
EC, CO, N02
CO, N02, EC, OC
Gasoline (OC, N03",
NH/)
Diesel (EC, OC, N03")
NOX, EC, ultrafine
count
Harvard Six
Cities
Phoenix, AZ
Phoenix, AZ
Santiago, Chile
Atlanta, GA
Atlanta, GA
Helsinki, Finland
t total mortality
tCV mortality
t CV mortality
tCV mortality
t respiratory mortality
tCVD ED visits
tCVD ED visits
ST-segment depression
Lag 0-1
Lag1
Lag1
Lag1
LagO
LagO
Lag 2
E
E
E
E
E
E
E
Human
Human
Human
Human
Human
Human
Human
Laden et al. (2000, 0121021
Mar etal. (2006, 086143)
Mar etal. (2000, 0017601
Cakmak etal. (2009, 1919951
Sarnat et al. (2008, 0979721
Sarnat et al. (2008, 0979721
Lanki et al. (2006, 089788)

December 2009
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Source Category
Speed-change factor
(Cu, S, aldehydes)
Motor vehicle/other
(Br, Pb, Se, Zn, N0r)
EC, Zn, Pb, Cu, Se
Local combustion
(NOX, ultrafine PM, Cu,
Zn, Mn, Fe)
Gasoline+ secondary
nitrate*
Gasoline+diesel*
Location
Vteke County,
NC
Tuxedo, NY
New Haven, CT
Helsinki, Finland
Birmingham, AL;
Atlanta, GA;
Pensacola, FL;
Centreville, AL
Birmingham, AL;
Atlanta, GA;
Pensacola, FL;
Centreville, AL
Health Effects
t blood urea nitrogen
t mean red cell volume
t blood PMN %
1 blood lymphocytes %
t von Willebrand factor
(vWF)
I protein C
t mean cycle length
tSDNN
t PNN50
t supraventricular ectopic
beats
| RMSSD
t respiratory symptoms
I mean PEF
cytotoxic responses
(potency)
inflammatory responses
(potency)
Time
Lag 15 h
Afternoon post-
exposure
Lag 0-2
Lag 0-5 avg
24 h post-exposure
24 h post-exposure
Study*1 sPecies Reference
E Human Riediker et al. (2004, 056992)
T Mouse Lippmann et al. (2005, 087453)
E Human Gent et al. (2009, 1803991
E Human Penttinen et al. (2006, 0879881
T Rat Seagrave et al. (2006, 0912911
T Rat Seagrave et al. (2006, 0912911
OIL COMBUSTION
V, Ni
V, Ni, Se
Ni
V, Ni
Boston, MA
Tuxedo, NY
Boston, MA
Boston, MA
t blood PMN %
1 blood lymphocytes %
tBALFAM%
|SDNN
| RMSSD
I respiratory rate
t lung PMN density
Following exposure
Following exposure
24 h post-exposure
Afternoon post-
exposure
During exposure
24 h post-exposure
T Dog Clarke et al. (2000, 0118061
T Mouse Lippmann et al. (2005, 0874531
T Dog Nikolov et al. (2008, 1568081
T Rat Saldiva et al. (2002, 0259881
COAL COMBUSTION
Se, S042"
Not provided
Harvard Six
Cities
Washington,
D.C.
t total mortality
t total mortality
Lag 0-1
Lag3
E Human Laden et al. (2000, 0121021
E Human Itoetal. (2006, 0883911
OTHER METALS
Cu smelter (not
provided)
Incinerator
Metal processing
(S042", Fe, NH4 , EC,
OC)
Phoenix, AZ
Washington,
D.C.
Atlanta, GA
tCV mortality
ftotal mortality
Negative association with
total and CV mortality
tCVD ED visits
LagO
LagO
LagO
E Human Mar etal. (2006, 0861431
E Human Ito et al. (2006, 0883911
E Human Sarnat et al. (2008, 0979721
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 Source Category   Location
Health Effects         Time        study1'  sPecies
              Reference
         r'CU'  Santiago, Chile
                         t respiratory mortality
              Lag1
Human    Cakmak et al. (2009, 1919951
WOODSMOKE/ VEGETATIVE BURNING
OC, K
OC, EC, K, NH4*
Total C
Phoenix, AZ
Atlanta, GA
Spokane, WA
t CV mortality
tCVD ED visits
t respiratory ED visits
Lag3
LagO
Lag1
E
E
E
Human
Human
Human
Mar etal. (2000, 0017601
Sarnat et al. (2008, 097972)
Schreuderetal. (2006, 097959)
UNNAMED FACTORS
Zn-Cu-V
Fe-Se-S042~
Br, Cl, Pb
Br, Pb
Br, Pb
Chapel Hill, NC
Chapel Hill, NC
Santiago, Chile
Boston, MA
Boston, MA
t blood fibrinogen
t BALF PMN
tCV mortality
t respiratory mortality
t BALF PMN %
t lung PMN density
18 h post-exposure
18 h post-exposure
Lag1
24 h post-exposure
24 h post-exposure
H
H
E
T
T
Human
Human
Human
Dog
Rat
Huang et al. (2003, 087377)
Huang et al. (2003, 087377)
Cakmak etal. (2009, 1919951
Clarke etal. (2000, 0118061
Saldiva et al. (2002, 025988)
Constituents not provided.
1 E = Epidemiologic study; H = Controlled human exposure study; T = Toxicological study
      An in vitro toxicological study that employed Chapel Hill PM10 used PCA but did not name
specific PM sources (Becker  et al., 2005, 088590). In this study, the release of IL-6 from human
alveolar macrophages and IL-8 from normal human bronchial epithelial cells was associated with a
PMio factor comprised of Cr, Al, Si, Ti, Fe, and Cu. No statistically significant effects were observed
for a second PMi0 factor (Zn, As, V, Ni, Pb, and Se).
      Those toxicological studies that did not apply groupings to the ambient PM2.5 speciation data
demonstrated a variety of results. Two Boston CAPs studies demonstrated lung oxidative stress
correlated with a number of individual PM2 5 constituents including, Mn, Zn, Fe, Cu, and Ca
(Gurgueira et al., 2002, 036535) and Al, Si, Fe, K, Pb, and Cu (Rhoden et al., 2004, 087969) in rats
using univariate regression.
      The remaining toxicological study that did not use ambient PM constituent groupings reported
a correlation between Zn and plasma fibrinogen in SH rats when constituents were  normalized per
unit mass of CAPs (Kodavanti et al., 2002, 035344).
6.6.3.   Summary by Health Effects
      Recent epidemiologic, toxicological, and controlled human exposure studies have evaluated
the health effects associated with ambient PM constituents and sources, using a variety of
quantitative methods applied to a broad set of PM constituents, rather than selecting a few
constituents a priori. As shown in Table 6-18, numerous ambient PM2.5 source categories have been
associated with health effects, including factors for PM from crustal and soil, traffic, secondary
SO42~, power plants, and oil combustion sources.  There is some evidence for trends and patterns that
link particular ambient PM constituents or sources with specific health outcomes, but there is
insufficient evidence to determine whether these patterns are consistent or robust.
      For cardiovascular effects, multiple outcomes have been linked to a PM crustal/soil/road dust
source, including cardiovascular mortality in Washington D.C. (Ito et al., 2006, 088391)and
Santiago,  Chile, (Cakmak  et al., 2009, 191995) and ST-segment changes in Helsinki (Lanki et al.,
2006, 089788). Los Angeles (Gong  et al., 2003, 042106). and Boston (Wellenius et al., 2003,
055691). Interestingly, the ST-segment changes have been observed in an epidemiologic panel study,
a controlled human exposure study, and a toxicological study, although the majority of the CAPs in
the controlled human exposure study was PMi0_2.5. Further support for a crustal/soil/road dust source
associated with cardiovascular health effects comes from a PM10 source  apportionment study in
Copenhagen that reported increased cardiovascular hospital  admissions (Andersen et al., 2007,
093201).
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      PM2.5 traffic and wood smoke/vegetative burning sources have also been linked to
cardiovascular effects. Cardiovascular mortality in Phoenix (Mar et al., 2000, 001760; 2006,
086143) and Santiago, Chile, (Cakmak  et al., 2009, 191995) was associated with traffic at lag 1.
Gasoline and diesel sources were associated with ED visits in Atlanta for cardiovascular disease at
lag 0 (Sarnat  et al., 2008, 097972). Cardiovascular mortality in Phoenix (Mar et al., 2000, 001760)
and ED visits in Atlanta (Sarnat et al., 2008, 097972) were associated with wood smoke/vegetative
burning.
      Studies that only examined the effects of individual PM2.5 constituents linked EC to
cardiovascular hospital admissions in a multicity analysis (Peng et al., 2009, 191998) and
cardiovascular mortality in California (Ostro et al., 2007, 091354; 2008, 097971).
      These studies suggest that cardiovascular effects may be associated with PM2.5 from motor
vehicle emissions,  wood or biomass burning, and PM (both PM2.5 and PMi0_2.5) from crustal or road
dust sources. In addition there are many studies that observed associations between other sources
(i.e., salt, secondary SO4 71ong-range transport, other metals) and cardiovascular effects, but at this
time, there does not appear to be a consistent trend or pattern of effects for those factors.
      There is less consistency in observed associations between PM sources and respiratory health
effects, which may be partially due to the fact that fewer studies have been conducted that evaluated
respiratory-related outcomes and measures. However, there is some evidence for associations with
secondary SO42~ PM2 5. Sarnat et al. (2008, 097972) found an increase in respiratory ED visits in
Atlanta that was associated with a PM2 5 secondary SO42~ factor. Decrements in lung function in
Helsinki (Lanki et al., 2006, 089788) and Los Angeles (Gong  et al., 2005, 087921)in asthmatic and
healthy adults, respectively, were also linked to this factor. Health effects relating to the
crustal/soil/road dust and traffic sources of PM included increased respiratory  symptoms  in
asthmatic children (Gent  et al., 2009, 180399)  and decreased PEF in asthmatic adults (Penttinen et
al., 2006, 087988). Inconsistent results were also observed in those PM25 studies that use individual
constituents to examine associations with respiratory morbidity and mortality, although Cu, Pb, OC,
and Zn were related to respiratory health effects in two or more studies.
      A few studies have identified PM2 5 sources associated with total mortality. These studies
found an association between mortality and a PM2 5 coal combustion factor (Laden  et al., 2000,
012102). while others linked mortality to a secondary SO42~/long-range transport PM2 5 source (Ito
et al., 2006, 088391: Mar et al., 2006, 086143).
      Recent studies have evaluated whether the variation in associations between PM2 5  and
morbidity and mortality or PM10 and mortality reflects differences in PM25 constituents (Bell  et al.,
2009, 191997; Dominici et al., 2007, 099135: Lippmann et al., 2006, 091165). In three studies (Bell
et al., 2009, 191997: Dominici et al., 2007, 099135: Lippmann et al., 2006, 091165) PMi0-mortality
effect estimates were greater in areas with a higher proportion of Ni in PM2 5, but the overall PMiq-
mortality association was diminished when New York City was excluded in a sensitivity  analysis in
two of the studies.  V was also found to modify  PMio-mortality effect estimates as well as those for
PM2 5 with respiratory and cardiovascular hospital admissions (Bell et al., 2009, 191997). When
examining the effect of species-to-PM2 5 mass proportion on PM2 5-mortality effect estimates Ni was
found to modify the association along with Al, As, Si, and SO42", but not V (Franklin et al., 2008,
097426).


6.6.4.   Conclusion

      Recent studies show that source apportionment methods have the potential to add useful
insights into which sources and/or PM constituents may contribute to different health effects. Of
particular interest are several epidemiologic studies that compared source apportionment methods
and the associated results. One set of studies  compared epidemiologic associations with PM25 source
factors using several methods - PCA, PMF, and UNMIX  - independently analyzed by separate
research groups (Hopke et al., 2006, 088390: Ito et al., 2006, 088391: Mar et al., 2006,  086143:
Thurston et al., 2005, 097949). Schreuder et al. (2006, 097959) compared UPM and two versions of
UNMIX to derive tracers and Sarnat et al. (2008, 097972) compared PMF, modified CMB, and a
single-species tracer approach. In all analyses, epidemiologic results based on the different methods
were generally in close agreement. The variation in risk estimates for daily mortality between source
categories was significantly larger than the variation between research groups  (Ito  et al.,  2006,
088391: Mar et al., 2006, 086143: Thurston  et al., 2005, 097949). Additionally, the variation in risk
estimates based on the source apportionment model used  had a much smaller effect than the
December 2009                                 6-211

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variation caused by the different source constituents. Further, the most strongly associated source
types were consistent across all groups. This supports the general validity of such approaches,
though greater integration of results would be possible if the methods employed for grouping PM
constituents were more consistent across studies and disciplines. Further research would aid
understanding of the contribution of different factors, sources, or source tracers of PM to health
effects by increasing the number of locations where similar health endpoints or outcomes are
examined.
      Overall, the results displayed in Table 6-18 indicate that many constituents of PM can be
linked with differing health effects and the evidence is not yet sufficient to allow differentiation of
those constituents or sources that are more closely related to specific health outcomes. These
findings are consistent with the conclusions of the 2004 PM AQCD (U.S. EPA, 2004, 056905). that a
number of source types, including motor vehicle emissions, coal combustion, oil burning, and
vegetative burning, are associated with health effects. Although the crustal factor of fine particles
was not associated with mortality in the 2004 PM AQCD (U.S. EPA, 2004, 056905). recent studies
have suggested that PM (both PM2.s and PMi0_2.5) from crustal, soil or road dust sources or PM
tracers linked to these sources are associated with cardiovascular effects. In addition, secondary
SO42~ PM2.5 has been associated with both cardiovascular and respiratory effects.
December 2009                                  6-212

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       isoproterenol-induced myocardial injury and healthy rats. Inhal Toxicol, 20: 199-203. 098625

Yang C-Y; Chen Y-S; Yang C-H; Ho S-C. (2004). Relationship between ambient air pollution and hospital admissions for
       cardiovascular diseases in Kaohsiung, Taiwan.  J Toxicol Environ Health A, 67: 483-493. 094376
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       Toxicol Environ Health A, 71: 1085-1090. 157160

Yang CY; Chen CC; Chen CY; Kuo HW. (2007). Air pollution and hospital admissions for asthma in a subtropical city:
       Taipei, Taiwan. J Toxicol Environ Health A, 70: 111-117. 092848

Yang CY; Chen CJ. (2007). Air pollution and hospital admissions for chronic obstructive pulmonary disease in a
       subtropical city: Taipei, Taiwan. J Toxicol Environ Health A, 70: 1214-1219. 092847

Yang CY; Cheng MH; Chen CC. (2009). Effects of Asian Dust  Storm  Events on Hospital Admissions for Congestive Heart
       Failure in Taipei, Taiwan. J Toxicol Environ Health A, 72: 324-328. 190341

Yang Q; Chen Y; Krewski D; Shi Y; Burnett RT; McGrail KM.  (2004). Association between particulate air pollution and
       first hospital admission for childhood respiratory illness in Vancouver, Canada. Arch Environ Occup Health, 59: 14-
       21.087488

Yeatts K; Svendsen E; Creason J; Alexis N; Herbst M; Scott J; Kupper L; Williams R; Neas L; Cascio W; Devlin RB;
       Peden DB. (2007). Coarse particulate matter (PM25-10) affects heart rate variability, blood lipids, and circulating
       eosinophils in adults with asthma. Environ Health Perspect, 115: 709-714.  091266

Yokota S; Seki T; Naito Y; Tachibana S; Hirabayashi N; Nakasaka T; Ohara N; Kobayashi H. (2008). Tracheal instillation
       of diesel exhaust particles component causes blood and pulmonary neutrophilia and enhances myocardial oxidative
       stress in mice. J Toxicol Sci, 33: 609-620. 190109

Yu O; Sheppard L; Lumley T; Koenig JQ; S. (2000). Effects of ambient air pollution on symptoms of asthma in Seattle-
       area children enrolled in the CAMP study. Environ Health Perspect, 108: 1209-1214. 013254

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       Ambient source-specific particles are associated with prolonged repolarization and increased levels of inflammation
       in male coronary artery disease patients. Mutat Res Fund Mol  Mech Mutagen, 621: 50-60. 097968

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       instillation of residual-oil fly ash (ROFA) induces brain lipid peroxidation  and behavioral changes in rats. Inhal
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       087489

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       analyses of time-series studies of air pollution and health.  Special Report. 157174

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       A multicity case-crossover analysis. Environ Health Perspect,  113: 978-982. 088069

Zanobetti A; Schwartz J. (2006). Air pollution and emergency admissions in Boston, MA. J Epidemiol Community Health,
       60: 890-895. 090195

Zanobetti A; Schwartz J. (2009). The effect of fine and coarse particulate air pollution on mortality: A national analysis.
       Environ Health Perspect, 117:  1-40. 188462

Zareba W; Couderc JP; Oberdorster G; Chalupa D; Cox C; Huang LS; Peters A; Utell MJ; Frampton MW. (2009). EGG
       parameters and exposure to carbon ultrafine particles in young healthy subjects. Inhal Toxicol, 21: 223-233. 190101

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       characterizing the pathway to disease. Int J Epidemiol, 35: 1347-1354. 157177

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       and modification by city characteristics. Occup Environ Med,  62: 718-725. 088068

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       ambient participate matter on pulmonary antimicrobial immune defense. Inhal Toxicol, 15: 131-150. 039009

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       lacking apolipoprotein E. Science, 258: 468-471. 157180

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    Chapter 7.  Integrated  Health Effects of
                  Long-Term  PM  Exposure
7.1.  Introduction

     This chapter reviews, summarizes, and integrates the evidence on relationships between health
effects and long-term exposures to various size fractions and sources of PM. Cardiopulmonary
health effects of long-term exposure to PM have been examined in an extensive body of
epidemiologic and toxicological studies. Both epidemiologic and toxicological studies provide a
basis for examining reproductive and developmental and cancer health outcomes with regard to
long-term exposure to PM. In addition, there is a large body of epidemiologic literature evaluating
the relationship between mortality and long-term exposure to PM.
     Conclusions from the 2004  PM AQCD are summarized briefly at the beginning of each
section, and the evaluation of evidence from recent studies builds upon what was available during
the previous review. For each health outcome (e.g., respiratory infections, lung function), results are
summarized for studies from the specific scientific discipline, i.e., epidemiologic and toxicological
studies. The major sections (i.e., cardiovascular, respiratory, reproductive/developmental, cancer)
conclude with summaries of the evidence for the various health outcomes within that category and
integration of the findings that lead to conclusions regarding causality based upon the framework
described in Chapter 1. Determination of causality is made for the overall health effect category,
such as cardiovascular effects, with coherence and plausibility being based upon the evidence from
across disciplines and  also across  the suite of related health outcomes including cause-specific
mortality. Section 7.6 provides detailed  discussions on the epidemiologic literature for long-term
exposure to PM and mortality. In each summary section (7.2.11, 7.3.9, 7.4.3, 7.5.4, and 7.6.5), the
evidence is briefly reviewed and independent conclusions drawn for relationships with PM2 5,
PMio.2.5, and UF particles (UFPs).



7.2.  Cardiovascular and Systemic  Effects

     Studies examining associations between long-term exposure to ambient PM (over months to
years) and CVD morbidity had not been conducted and thus were not included in the 1996 or 2004
PM Air Quality Criteria Documents (U.S. EPA, 1996, 079380: U.S. EPA, 2004, 056905). A number
of studies were included in the 2004 PM AQCD that evaluated the effect of long-term PM2.5
exposure on cardiovascular mortality and found consistent associations. No toxicological studies
examined chronic atherosclerotic  effects of PM exposure in animal models. However, a subchronic
study that evaluated atherosclerosis progression in hyperlipidemic rabbits was discussed and  this
study provided the foundation for the subsequent work that has been conducted in this area (Suwa et
al., 2002, 028588). No previous toxicological studies evaluated effects of subchronic or chronic PM
exposure on diabetes measures, or HR or HRV changes, nor were there animal toxicological studies
included in the 2004 PM AQCD that evaluated systemic inflammatory or blood coagulation markers
following subchronic or chronic PM exposure.
     Several new epidemiologic  studies have examined the long-term PM-CVD association among
U.S. and European populations. The studies  investigate the  association of both PM2.5 and PMi0
exposures with a variety of clinical and  subclinical CVD outcomes. Epidemiologic and toxicological
studies have provided  evidence of the adverse effects of long-term exposure to PM2.5 on
 Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
 Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
 developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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cardiovascular outcomes, including atherosclerosis, clinical and subclinical markers of
cardiovascular morbidity, and cardiovascular mortality. The evidence of these effects from long-term
exposure to PMi0_2.5 is weaker.


7.2.1.  Atherosclerosis

      Atherosclerosis is a progressive disease that contributes to several adverse outcomes,
including acute coronary syndromes such as myocardial infarction, sudden cardiac death, stroke and
vascular aneurysms. It is multifaceted, beginning with an early injury or inflammation that promotes
the extravasation of inflammatory cells. Under conditions of oxidative or nitrosative stress and high
lipid or cholesterol concentrations, the vessel wall undergoes a chronic remodeling that is
characterized by the presence of foam cells, migrated and differentiated smooth muscle cells, and
ultimately a fibrous cap. The advanced lesion that develops from this process can occlude perfusion
to distal tissue, causing ischemia, and erode, degrade, or even rupture, revealing coagulant initiators
(tissue factor) that promote thrombosis,  stenosis, and infarction or stroke. Several detailed reviews of
atherosclerosis pathology have been published elsewhere (Ross, 1999, 156926; Stacker  and Keaney,
2004, 1570131


7.2.1.1.   Epidemiologic Studies



      Measures of Atherosclerosis

      Although no study has examined the association between long-term PM  exposure and
longitudinal change in subclinical markers of atherosclerosis,  several cross sectional studies have
been conducted. Markers of atherosclerosis used in these studies include coronary artery calcium
(CAC), carotid intima-media thickness (CIMT), ankle-brachial index (ABI), and abdominal aortic
calcium (AAC). These measures are descried briefly below.
      CAC represents the accumulation of calcium in coronary artery macrophages and represents
an advanced stage of atherosclerosis. As such CAC is a measure of atherosclerosis assessed by non-
contrast, cardiac-gated electron beam computed tomography (EBCT) or multidetector computed
tomography (MDCT) of the coronary arteries in the heart (Greenland and Kizilbash, 2005, 156496;
Hoffmann et al, 2005, 156556; Mollet et al, 2005, 155988). The prevalence of CAC is strongly
related to age. Few people have detectable CAC in their second decade of life but the prevalence of
CAC rises to  approximately 100% by age 80 (Ardehali et al., 2007, 155662). Previous studies
suggest that while the absence of CAC does not rule out atherosclerosis, it does imply a very low
likelihood of significant arterial obstruction (Achenbach and Daniel, 2001, 156189; Arad et al.,
1996, 155661; Shaw et al., 2003, 156083; Shemesh et al., 1996, 156085). Conversely, the presence
of CAC confirms the existence of atherosclerotic plaque and the amount of calcification varies
directly with the likelihood of obstructive disease (Ardehali et al., 2007, 155662). CAC is a
quantified using the Agatston method (Agatston et al., 1990, 156197). Its repeatability depends on
the laboratory and the method of calculation (O'Rourke et al.,  2000, 192159). Agatston scores are
frequently used to classify individuals into one of five groups  (zero; mild; moderate; severe;
extensive) or according to age- and sex-specific percentiles of the CAC distribution (Erbel et al.,
2007, 155768).
      CIMT is a measure of atherosclerosis assessed by high-resolution, B-mode ultrasonography of
the carotid arteries in the neck, the walls of which have inner (intimal), middle (medial) and outer
(adventitial) layers (Craven et al., 1990, 155740; O'Leary et al., 1999, 156826; Wendelhag et al.,
1993, 157136).  CIMT estimates the distance in mm or (im between the innermost (blood-intima) and
outermost (media-adventitia) interfaces, often by averaging over three arterial segments in the
common carotid, carotid bulb, and internal carotid artery (Amato et al., 2007, 155656). CIMT has
been associated with atherosclerosis risk factors (Heiss et al.,  1991, 156535; O'Leary et al., 1992,
156825; Salonen and Salonen, 1991, 156938). prevalent coronary heart disease (Chambless et al.,
1997, 156329; Geroulakos et al.,  1994, 155788). and incident  coronary and cerebral events (O'Leary
et al., 1999, 156826; van der Meer et al., 2004, 156129). Several studies have indicated that CIMT
measurements are accurate (Girerd et al., 1994, 156474; Pignoli et al., 1986, 156026; Wendelhag et
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al., 1991, 157135) and reproducible (Montauban et al, 1999, 156777; Smilde et al, 1997, 156988;
Willekes et al., 1999, 157147), especially for the common carotid artery (Montauban et al., 1999,
156777).
      ABI, which is also known as the ankle-arm or resting (blood) pressure index, is a measure of
lower extremity arterial occlusive disease commonly caused by advanced atherosclerosis (Weitz et
al., 1996, 156150). It is assessed by continuous wave Doppler and manual or automated
oscillometric sphygmomanometry, the latter having been shown to have higher repeatability and
validity (Weitz et al., 1996, 156150). ABI is defined as the unitless ratio of ankle to brachial systolic
blood pressures measured in mmHg. As ankle pressure is normally equal to or slightly higher than
arm pressure (resulting in an ABI > 1.0), epidemiologic studies typically define the normal ABI
range as 0.90 to 1.50 (Resnick et al., 2004,  156048). Low ABI has been associated with all-cause and
CVD mortality (Newman et al., 1993, 156805; Vogt et al., 1993, 157100). as well as myocardial
infarction and stroke (Karthikeyan and Lip, 2007, 156626).
      AAC is a measure of atherosclerosis  assessed by non-contrast, EBCT or MDCT of the
abdominal aorta. It is scored much like CAC (Agatston et al., 1990, 156197). but the age-specific
prevalence and extent of AAC is greater, particularly among women and at ages >50 yr. Although
AAC has not been studied as extensively as CAC, it is associated with carotid and coronary
atherosclerosis as well as cardiovascular morbidity and mortality (Allison et al., 2004, 156210;
Allison et al., 2006, 155653; Hollander et al., 2003, 156562; Khoury et al., 1997, 156636; Oei et al.,
2002, 156820; Walsh et al., 2002, 157103; Wilson et al., 2001, 156159; Witteman et al., 1986,
156161) and measurements are sufficiently reproducible to allow serial investigations over time
(Budoff et al., 2005, 192105).

      Study Findings

      Diez Roux et al. (2008,  156401) conducted cross-sectional analyses of the association of three
of these subclinical markers of atherosclerosis  (CAC, CIMT and ABI), collected from 2000 to 2003
during baseline examinations  of participants enrolled in the  Multi-Ethnic Study of Atherosclerosis
(MESA), with long-term exposure to PM25 and PMi0. The study population included 5,172
ethnically diverse people (53% female) residing in Baltimore, MD;  Chicago, IL; Forsyth County,
NC; Los Angeles, CA; New York, NY; and St.  Paul, MN ranging in age from 45 to 84 yr old.
Authors used spatio-temporal  modeling of pollutant concentrations, weather and demographic data
to impute 20-yr avg exposures to PM2 5 and PMi0. They reported small increases in CIMT of 1%
(95% CI: 0-1.4) and 0.5% (95% CI: 0-1), which correspond to absolute changes of 8 (95% CI: 0-12)
and 7 (95% CI:  0-14) urn, per 10 ug/m3 increase in 20-yr avg PMi0  and PM25 concentration,
respectively. Evidence of age-, gender-, lipid- and smoking-related susceptibility was lacking.  They
also reported weak, non-significant increases in the relative  prevalence of CAC of 1% (95% CI: -2 to
4) and 0.5% (95% CI: -2 to 3) per 10 ug/m3 increase in PMi0 and PM2.5, respectively. Among the
subset of 2,586 participants with EBCT-identified calcification, similarly weak associations were
observed. There was little evidence of modification of the CAC associations by demographic,
socioeconomic or clinical characteristics. Finally, the authors report no differences in mean ABI with
PMio or PM25 concentrations. The null findings for ABI exhibited little heterogeneity among
participant subgroups and were similarly null when ABI was modeled as a dichotomous outcome
using a cutpoint of 0.9 units.
      MESA investigators also examined the chronic PM2 5-AAC association in a residentially stable
subset of 1,147 participants (mean age = 66 yr; 50% female) randomly selected from all MESA
centers, except Baltimore, MD for enrollment in its Aortic Calcium Ancillary Study (Allen et al.,
2009, 156209). The authors used kriging and inverse residence-to-monitor distance-weighted
averaging of EPAAQS data to estimate 2-yr mean exposures to PM25. In cross-sectional analyses,
the authors found a 6% (95% CI: -4 to 16) excess risk of a non-zero Agatston score and an 8% (95%
CI: -30 to 46) increase in AAC, i.e., approximately 50 (95% CI: -251 to 385) Agatston units, per
10 ug/m3 increase in PM25 concentration. These associations were stronger among users than non-
users of lipid lowering drugs.
      Kunzli et al. (2005, 087387) used baseline data collected between 1998-2003 from two
randomized  placebo-controlled clinical trials, the Vitamin E Atherosclerosis Progression Study
(VEAPS) and the B-Vitamin Atherosclerosis Intervention Trial (BVAIT), for their ancillary cross-
sectional analyses of the effect of long-term PM25 exposure on CIMT. The study population included
798 residents of the greater Los Angeles, CA area who were more than 40 yr old at baseline and 44%
were female. The authors used universal kriging of PM25 data from 23 state and local monitors
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operating in 2000 to estimate 1-yr avg exposure to PM25 at each participant's geocoded U.S. Postal
Service ZIP code. They found a 4.2% (95% CI:  -0.2 to 8.9) or approximately 32 (95% CI: -2 to
68) urn increase in  CIMT per 10 ug/m  increase in PM25 concentration. In contrast to findings from
the relatively large, ethnically diverse, yet geographically overlapping MESA ancillary study
described above, PM-related increases in CIMT were two- to three-fold larger among older and
female participants taking lipid lowering drugs in this study. PM-related increases in CIMT were
also higher in never smokers when compared with current or former smokers.
      Hoffmann et al. (2007, 091163) conducted a cross-sectional analysis of data collected at
baseline (2000-2003) for 4,494 residents of Essen, Mulheim and Bochum, Germany enrolled in the
Heinz Nixdorf Recall Study from 2000 to 2003. The age of participants ranged from 45-74 yr and
51% were female. In this  cross-sectional study the authors used dispersion and chemistry transport
modeling of emissions, climate and topography  data to estimate  1-yr avg exposure to PM2 5 in 2002
(the midpoint of the baseline exam.) They reported an imprecise 43% (95% CI: -15 to 115) or 102
(95% CI: -77 to 273) Agatston unit increase in CAC per 10 ug/m3 increase in PM2.5. Differences in
strength of association between subgroups defined by demographic and clinical characteristics were
small. The authors  reported a more consistent association of CAC with traffic exposure (distance
from a major roadway) than with PM2 5 in this study.
      In a subsequent analysis of these data, Hoffmann et al.  (2009, 190376) examined the PM-ABI
association in this population.  In this cross-sectional study, no changes in ABI were observed in
association with PM2 5 concentration nor was evidence of effect modification by demographic and
clinical characteristics apparent. As in the previous study (Hoffmann et al., 2007, 091163). residing
near a major roadway was a stronger predictor of atherosclerotic changes. Absolute changes in ABI
of-0.024 (95% CI: -0.047 to -0.001) were associated with living within 50 m of a major roadway
compared to living more than 200 m away.
      Each of the studies  described above relied on cross-sectional analyses examining differences
in long-term average PM2 5 concentrations across space (as well as time to the extent baseline
examinations were conducted over time). Such associations may reflect the effect of compositional
differences in PM25 as well as the effect of higher PM25 concentrations.  Most associations of PM25
with CAC (Diez  et al., 2008, 156401: Hoffmann et al., 2007, 091163). CIMT (Diez et al., 2008,
156401: Kunzli et al., 2005, 087387). ABI (Diez et al., 2008, 156401:  Hoffmann et al., 2009,
190376) and AAC (Allen et al., 2009, 156209) reviewed in this section were weak and/or imprecise.
However, several factors including exposure measurement error, variation in baseline measures
atherosclerosis, as well as limited power may contribute to the insensitivity of these cross-sectional
studies to detect small differences in CAC, CIMT, ABI and AAC. The study by Hoffmann et al.
(2007, 091163). which reported large, imprecise and non-significant increases in CAC in association
with PM2 5, is not distinguished from the other studies reviewed by a superior study design or larger
sample size. The several fold difference in the magnitude of CIMT associations reported by Kunzli
et al. (2005, 087387) and  Diez Roux et al. (2008, 156401) may be related to differences between the
study populations. The ambient PM concentrations from these studies  are characterized in Table 7-1.


7.2.1.2.   lexicological Studies

      In the only study of this kind described in the 2004 PM AQCD,  Suwa et al. (2002, 028588)
demonstrated more advanced atherosclerotic lesions based on phenotype and volume fraction in the
left main and right  coronary arteries of rabbits exposed to PMi0 (5 mg/kg, 2 times/wkx4 wk).
Although this study was conducted using IT exposure methodology at a relatively high dose, it
provided the first experimental evidence that PM exposure may result in progression of
atherosclerosis. Recent toxicological studies conducted using inhalation  exposures have replicated
these findings at  relevant  concentrations and are discussed below.


      CAPS

      New studies  have demonstrated increased atherosclerotic plaque area in aortas of ApoE"7" mice
exposed to PM25 CAPs for 4-6 mo (6 h/day><5 days/wk). Average CAPs  concentrations ranged from
85 to 138 ug/m and all of the studies were conducted in Tuxedo or Manhattan, NY. Chen and
Nadziejko (2005, 087219) reported that the percentage of aortic intimal surface covered by
atherosclerotic lesions in ApoE"7" mice was increased. In male ApoE"77LDLR"7" mice, both lesion area
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and cellularity in the aortic root were enhanced by Tuxedo, NY CAPs exposure, although there was
no change in lipid content. Genetic profiles within plaques recovered from ApoE"" mice included
many of the molecular pathways known to contribute to atherosclerosis, including inflammation
(Floyd et al., 2009, 190350). Sun (2005, 087952) similarly demonstrated an enhancement of
atherosclerosis in ApoE" mice exposed Tuxedo, NY CAPs. Plaque area in the aortic arch and
abdominal aorta was significantly increased in the PM-exposed, high fat-chow group compared to
air-exposed, high fat-chow group. Macrophage infiltration in the abdominal aorta was also observed
in the groups exposed to CAPs. A study conducted in Manhattan for 4 mo (May- September 2007)
showed that PM2.5 CAPs exposure increased atherosclerotic plaque area and led to higher levels of
macrophage infiltration, collagen deposition, and lipid composition in thoracic aortas of ApoE"7" mice
(Ying et al., 2009, 190111). which is consistent with the previous two studies described that were
conducted in Tuxedo, NY.
      Alteration of vasomotor function has been observed in aortic rings of ApoE~'~ mice on a high
fat diet with long-term exposure to CAPs (Sun et al., 2005, 087952; Ying et al., 2009, 190111). Sun
(2005, 087952) reported that. PM2.5-exposed animals  exhibited increased vasoconstrictor
responsiveness to serotonin and PE. Increased ROS and elevated iNOS  protein expression in aortic
sections of CAPs-exposed mice may have resulted alterations in the NO pathway and generation of
peroxynitrite that could have affected vascular reactivity. In contrast, Ying, et al. (2009, 190111)
demonstrated decreased maximum constriction induced by PE following Manhattan  CAPs exposure.
Pretreatment with the soluble guanylate cyclase (sGC) inhibitor ODQ attenuated the response,
indicating that CAPs exposure resulted in abnormal NO/sGC signaling. Expression of iNOS mRNA
and protein was increased in aortas of CAPs-exposed mice, further supporting a role for NO
production. In conjunction with increased NO, aortic  superoxide production was demonstrated that
appeared to be partially driven by increased NADPH  oxidase activity. The difference in
vasoconstrictor responses between these two studies may be attributable to varying durations
(6 versus 4 mo, respectively) or CAPs compositions.
      Sun (2005, 087952) and Ying et al. (2009, 190111) reported similar relaxation responses to
ACh for air- and CAPs-exposed mice. However, Manhattan CAPs-exposed mice had a markedly
decreased response to A23187, indicating that NO release occurred via  Ca2+-dependent mechanisms
(Ying et al., 2009, 190111). Abnormal eNOS function is likely responsible for the decreased
relaxation response, as activation of eNOS (but not iNOS) is Ca2+-dependent.
      A recent study (Sun et al., 2008, 157033) that was part of the research described above (Sun et
al., 2005, 087952) investigated tissue factor (TF) expression in aortas, which is a major regulator of
hemostasis and thrombosis following vascular injury  or plaque erosion. In PM2.5-exposed ApoE"7"
mice on a high-fat diet, TF was significantly elevated in the plaques of aortic sections compared to
air-exposed mice on the high-fat diet. TF expression was generally detected in (1) the extracellular
matrix surrounding macrophages and foam cell-rich areas; and (2) around smooth muscle cells.
      One new study of CAPs PM25 or UFPs derived from traffic was conducted. Araujo et al.
(2008, 156222) compared the relative impact of UF (0.01-0.18 urn) and fine (0.01-2.5 urn) PM
inhalation on aortic lesion development in ApoE"" mice following a 40-day exposure (5
h/day><3 days/wk for 75 total h). Animals were on a normal chow diet and exposed to CAPs in a
mobile inhalation laboratory parked 300 m from a freeway in downtown Los Angeles. Exposure
concentrations were -440 ug/m3 for PM25 and -110 ug/m3 for UFPs, and the number concentrations
were roughly equivalent (4.56*105 and 5.59*105  particles/cm3 for PM25 and UFPs, respectively).
Significant increases in plaque size (estimated by lesions at the aortic root) were reported for mice
exposed to  UFPs only. The lesions were largely comprised of macrophages with intracellular lipid
accumulation. Increased total cholesterol measured at the end of the exposure protocol was observed
only in the  PM2 5 group. HDL isolated from the UF PM-exposed mice demonstrated  decreased anti-
inflammatory protective capacity against LDL-induced monocyte chemotactic activity in an in vitro
assay. The livers from the UFP-exposed mice demonstrated significant increases in lipid
peroxidation and several stress-related gene products  (catalase, glutathione S-transferase Ya,
NADPH-quinone oxidoreductasel, superoxide dismutase 2). Thus, UFPs in these exposures had a
substantially greater impact on the systemic response than did  PM2 5.
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      Ambient Air

      A study employing young BALB/c mice examined the effects of a 4-month exposure (24
h/dayx7 days/wk) to ambient air on arterial histopathology (Lemos et al., 2006, 088594). Outdoor
exposure chambers were located in downtown Sao Paulo, Brazil next to streets of high traffic
density. In the control chamber, PMi0 and NO2 were filtered with 50% and 75% efficiency,
respectively. The average pollutant concentrations were 2.06 ppm for CO (8-h mean), 104.75 ug/m3
for NO2 (24-h mean), 11.07 ug/m3 for SO2 (24-h mean),  and 35.52 ug/m3 for PMi0 (24-h mean) at a
monitoring site within 100 m of the inhalation chambers. The pulmonary and coronary arteries
demonstrated significant decreases in L/W ratio for animals exposed to the entire ambient mixture
compared to controls, indicating thicker walls in these vessels. There was no difference reported for
the L/W ratio in renal arteries. Morphologic examination suggested that the increases in L/W ratio
were due to muscular hypertrophy rather than fibrosis. The results of this study indicate vascular
remodeling of the pulmonary and coronary arteries, as opposed to changes in tone.
      To examine the role of systemic inflammation and recruitment of monocytes into plaque tissue
as a possible pathway for accelerated atherosclerosis, Yatera et al. (2008, 157162) exposed female
Watanabe heritable hyperlipidemic rabbits  (42 week old) to Ottawa PM10 (EHC-93) via IT
instillation (5 mg/rabbit; approximately 1.56 mg/kg) twice a week for 4 wk. Transfusion of whole
blood harvested to from exposed and non-exposed animals to donor rabbits supplied labeled
monocytes for assessment of monocyte recruitment from the blood to the aortic wall. The  fraction of
aortic surface and volume of aortic wall taken up by atherosclerotic plaque was increased  and the
number of labeled monocytes in the atherosclerotic plaques was elevated in rabbits exposed to PMi0.
In addition, labeled monocytes were attached onto the endothelium overlying atherosclerotic plaques
and the number that migrated into the smooth muscle underneath plaques in aortic vessel walls was
greater with PMi0 exposure compared to control. These responses were not observed in normal
vessel walls. ICAM-1 and VCAM-1 expression was elevated in atherosclerotic lesions, likely
indicating enhanced monocyte adhesion to endothelium and migration into plaques. Monocytes in
plaque tissue stained with immunogold demonstrated foam cell characteristics, which were more
numerous in the rabbits exposed to PMi0.


      Gasoline Exhaust

      Lund and colleagues (2007, 125741) used whole emissions from gasoline exhaust to
investigate changes in the transcriptional regulation of several gene products with known roles in
both the chronic promotion and acute degradation/destabilization of atheromatous plaques. These
50-day exposures (6 h/day><7 days/wk)  employed ApoE~'~ mice on high-fat chow and the
concentrations of the high exposure group were 61 ug/m3 for PM, 19 ppm for NOX, 80 ppm for CO,
and 12.0 ppm for total hydrocarbons. The average particle number median diameter was
approximately 15 nm (McDonald et al., 2007, 156746). Dilutions of gasoline engine emissions
induced a concentration-dependent increase in transcription of matrix metalloproteinase (MMP)
isoform 9, ET-1, and HO-1 in aortas;  MMP-3 and -9 mRNA levels were only increased in animals in
the highest exposure group. Strong increases in oxidative stress markers (nitrotyrosine and TEARS)
in the aortas were also observed. However, using a high-efficiency particle trap, they established that
most of the effects were caused by the gaseous portion of the emissions and not the particles. This
study  did not directly address lesion area.


7.2.2.  Venous Thromboembolism

      One epidemiologic study examined the relationship between long term PMi0 concentration,
venous thromboembolism, and laboratory measures of hemostasis (prothrombin and activated partial
thomboplastin times [PT; PTT]). PT and PTT measure the extrinsic and intrinsic blood coagulation
pathways, the former activated in response to blood vessel injury, the  latter, key to subsequent
amplification of the coagulation cascade and propagation of thrombus (Mackman et  al., 2007,
156723). Decreases in PT and PTT are consistent with a hypercoagulable, prothrombotic state.
December 2009                                  7-6

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7.2.2.1.   Epidemiologic Studies

      Baccarelli et al. (2008, 157984) studied 2,081 residents (56% female) of the Lombardy region
of Italy whose ages ranged from 18 to 84 yr old. In this case-control study of 871 patients with
ultrasonographically or venographically diagnosed lower extremity deep vein thrombosis (DVT) and
1,210 of their healthy friends or relatives (1995-2005), the authors used arithmetic averaging of PMi0
data available at 53 monitors in nine geographic areas to estimate 1-yr avg residence-specific
exposures. They found -0.06 (95% CI: -0.11 to 0) and -0.12 (95% CI:  -0.23 to 0) decreases in
standardized correlation coefficients for PT as well as 0.01 (95% CI: -0.03 to 0.04) and -0.09 (95%
CI:  -0.19 to 0.01) decreases in standardized correlation coefficients for PTT among cases and
controls, respectively, per 10 ug/m3 increase in PM10. Patients with DVT who were taking heparin or
coumarin anticoagulants were not asked to stop taking them before measurement of PT and aPTT. Of
additional note, PT was neither adjusted for differences in reagents used to determine it nor
conventionally reported as the International Normalized Ratio (INR).  The ambient PM
concentrations from this study are characterized in Table 7-1.


7.2.3.  Metabolic Syndromes



7.2.3.1.   Epidemiologic Studies

      Chen and Schwartz (2008,  190106) studied 2,978 residentially stable participants in 33 U.S.
communities (age range = 20-89 yr; 49% female) who were examined during phase 1 of the National
Health and Nutrition Examination Survey III (1989-1991). In this cross-sectional study, the authors
used inverse-distance weighted averaging of U.S. EPA AQS monitored data from participant and
adjacent counties of residence to estimate 1-yr avg exposures to PMi0. They found that after
adjustment, residents of communities with lower PMi0 concentrations had fewer white blood cells
than residents of communities with  higher PMi0 concentrations. This difference increased with
increasing number of metabolic abnormalities (insulin resistance; hypertension;
hypertriglyceridemia; low high-density lipoprotein cholesterol; abdominal obesity) reported by the
participant. This observed difference across individuals with different degrees of metabolic
abnormalities supports the concept that the presence of a metabolic syndrome may impart greater
susceptibility to PM-associated long-term CVD effects.


7.2.3.2.   lexicological Studies

      Diabetics as  a potentially susceptible subpopulation have only recently been evaluated. A
toxicological study of a diet-induced obesity mouse model (C57BL/6  fed high-fat chow for 10 wk)
examined the effects of a 128-day PM2.5 CAPs exposure (mean mass concentration 72.7  ug/m3;
Tuxedo, NY) on insulin resistance,  adipose inflammation, and visceral adiposity (Sun et  al., 2009,
190487). Elevated fasting glucose and insulin levels were observed in CAPs-exposed mice compared
to air-exposed during the glucose tolerance test. Aortic rings of mice exposed to CAPs demonstrated
decreased peak relaxation to ACh or insulin, which was associated with reduced NO bioavailability.
Additionally, insulin signaling was impaired in aortic tissue via lowered endothelial Akt
phosphorylation. Increases in adipokines and systemic inflammatory markers (i.e., TNF-a, IL-6,
E-selectin, ICAM-1, PAI-1, resistin, leptin) were reported for CAPs-exposed mice.  CAPs resulted in
increased visceral and mesenteric fat mass, as well as greater adipose tissue macrophages in
epididymal fat pads and larger adipocyte size compared to mice in the filtered air group.  The results
of this study demonstrate that PM2.5 exposure can exaggerate insulin resistance, visceral  adiposity,
and inflammation in mice fed high-fat chow.
December 2009                                  7-7

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7.2.4.  Systemic Inflammation, Immune Function, and  Blood Coagulation



7.2.4.1.   Epidemiologic Studies

      As discussed in Section 7.2.3.1, Chen and Schwartz (2008, 190106) conducted a cross-
sectional study in 33 U.S. communities and used inverse-distance weighted averaging of U.S. EPA
AQS monitored data from participant and adjacent counties of residence to estimate 1-yr avg
exposures to PMi0 (median concentration within quartiles = 23.1, 31.2, 38.8 and 53.7 ug/m3). They
found that after adjustment, residents of communities in quartile 1 had 138 (95% CI: 2-273) fewer
white blood cells (xl06/L) than residents of communities in quartiles 2-4. This difference increased
with increasing number of metabolic abnormalities.
      Forbes et al. (2009, 190351) studied approximately 25,000 adults (age > 16 yr; 53% female)
who were representatively sampled from 720 English postcode sectors and participated in the Health
Survey for England (1994, 1998 and 2003). In this fixed-effects meta-analysis of year-specific cross-
sectional findings, the authors used dispersion modeling of emissions and weather data to estimate
2-yr avg exposures to PMi0 at participant postcode sector centroids (median in 1994, 1998 and 2003
= 19.5, 17.9 and 16.2 ug/m3, respectively). They found little evidence of a PM10-inflammatory
marker association, i.e., only a -0.08% (95% CI: -0.25 to 0.10) decrease in fibrinogen concentration
and a 0.14% (95% CI: -1.00 to 1.30) increase in CRP concentration per 1 ug/m3 increase in PMi0.
      Calderon-Garciduenas et al. (2007, 091252) compared residentially stable, non-smoking
healthy children (age range: 6-13 yr) living and attending school between 2003-2004 in Mexico City
(historically high PM; altitude 2,250 m) and Polotitlan (historically low PM; altitude 2,380 m). In
this ecologic study, residents of Mexico City (n = 59; 93% female) had fewer white blood cells and
neutrophils (xlOvL) than residents of Polotitlan (n = 22; 69% female): unadjusted mean 6.2 (95%
CI: 5.7-6.6) versus 6.9 (95% CI: 6.3-7.5) and 2.9 (95% CI: 2.3-3.5) versus 3.8 (95% CI: 3.2-4.4),
respectively.
      Calderon-Garciduenas et al. (2009, 192107) subsequently compared 37 unadjusted mean
measures of immune function and inflammation among an expanded number of these participants.
They found that under a two-sided type I error rate (a) = 0.05, 16 (43%) of the measures were
significantly different in residents of southwest Mexico City (n = 66; 48% female) than those in
Polotitlan (n = 93; 57% female). However, only 8 measures were significantly different after Bon
Ferroni-correction (a =  0.05 / 37 = 0.001) and even fewer would be after adjustment for reported
correlation between the measures of immune function and inflammation, e.g., CRP and
lipopolysaccharide binding protein (Pearson's r = 0.71).
      Two cross-sectional analyses of PMi0 concentration and markers of immune function or
inflammation have been conducted with significant changes observed in the NHANES population
(stronger effects among those with metabolic disorders) (Chen and Schwartz, 2008, 190106) but not
in a relative large survey of adults, which was conducted in England  (Forbes et al., 2009, 190351).
Ecological analyses comparing children in high versus low pollution regions in Mexico show
differences in unadjusted blood markers that may be  related to PM concentration or other
unmeasured risk factors that differs across the communities studied (Calderon-Garciduenas et al.,
2007, 091252; Calderon-Garciduenas et al., 2009, 192107).


7.2.4.2.  lexicological Studies

      In addition to the PM2.5 study mentioned previously that showed increased TF expression (an
important initiator of thrombosis) in aortas of ApoE"7" mice following subchronic CAPs exposure
(Sun et al., 2008, 157033). three recent studies examined hematology and clotting parameters in rats
and mice exposed to DE, gasoline exhaust, or hardwood smoke for 1 week or 6 mo (Reed et al.,
2004, 055625: Reed et al., 2006, 156043: Reed et al., 2008,  156903). In all studies, male and female
F344 rats were exposed to the mixtures by whole-body inhalation for 6 h/day, 7 day/wk. Respiratory
effects for these studies are presented in Section 7.3.3.
December 2009                                  7-8

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      Diesel Exhaust

      The target PM concentrations in the DE study was 30, 100, 300, and 1,000 ug/m3 and the
MMAD was 0.10-0.15 um (Reed et al., 2004, 055625). Male and female rats exposed to DE at the
highest concentration (NO concentration 45.3 ppm; NO2 concentration 4.0 ppm; CO concentration
29.8 ppm; SO2 concentration 365 ppb) for 6 mo demonstrated decreased serum Factor VII, but no
change in plasma fibrinogen or thrombin anti-thrombin complex (TAT) (Reed et al., 2004, 055625).
White blood cells were decreased only in female rats in the highest exposure group. Another DE
study  of shorter duration (4 wk, 4 h/day, 5day/wk; PM mass concentration 507 or 2201 ug/m3, CO
1.3 and 4.8 ppm, NO <2.5 and 5.9 ppm, NO2 O.25 and 1.2 ppm, SO2 0.2 and 0.3 ppm for low and
high PM exposures, respectively) did not demonstrate changes in hematologic parameters or those
related to coagulation (i.e., PT, PPT, plasma fibrinogen, D-dimer) or inflammation  (i.e., CRP) in SH
or WKY rats (Gottipolu et al., 2009, 190360). Together, these findings do not support a DE-related
stimulation of blood coagulation following 1 or 6 mo of exposure.


      Hardwood Smoke

      The target PM concentrations in the hardwood smoke study was 30, 100, 300, and 1,000 ug/m3
and the MMAD was 0.25-0.36 um (Reed et al., 2006, 156043). In male rats exposed to hardwood
smoke, the mid-low group (PM concentration 113 ug/m3; NO, NO2, SO2 concentrations 0 ppm; CO
concentration 1,832.3 ppm) had the greatest responses in hematology parameters, including
increased hematocrit, hemoglobin,  lymphocytes, and decreased segmented neutrophils (Reed et al.,
2006, 156043). Platelets were elevated in male and female rats after 1 week of exposure, but this
response returned to control values following the 6-month exposure. No changes were observed for
any coagulation markers at 6 mo.


      Gasoline Exhaust

      PM mass in the gasoline exhaust study ranged from 6.6 to 59.1 ug/m3, with the corresponding
number concentration between 2.6><104 and 5.0><105 particles/cm3; the dilutions for the gasoline
exhaust were 1:10,  1:15 or 1:90 and filtered PM at the 1:10 dilution (Reed et al., 2008, 156903).
Similar to the responses observed with hardwood smoke, male and female rats in the mid- and high-
gasoline exhaust exposure groups (NO concentrations 11.9 and 18.4 ppm; NO2 concentrations 0.5
and 0.9 ppm; CO concentration 73.2 and 107.3 ppm;  SO2 concentration 0.38 and 0.62 ppm,
respectively) demonstrated elevated hematocrit and hemoglobin; RBC count was also elevated in
these groups (Reed et al., 2008, 156903). The only  response that appeared somewhat dependent on
the presence of particles was increased RBC in female rats at 6 mo, although the authors attributed
the observed increases to the high concentration of CO.
      Collectively,  these studies do not indicate robust systemic inflammation or coagulation
responses in F344 rats following 6-month exposures to diesel, hardwood smoke, or gasoline exhaust.
The limited effects  that were observed could possibly be due to the varying gas concentrations in the
exposure mixtures.


7.2.5.  Renal and Vascular Function

      Two recent epidemiologic studies have tested associations between PM exposure and
indicators of renal and vascular function (urinary albumin to creatinine ratio [UACR] and blood
pressure). UACR is a measure of urinary albumin excretion (National Kidney Foundation, 2008,
156796). When calculated as the ratio of albumin to creatinine concentrations in untimed ("spot")
urine samples, UACR approximates 24-h urinary albumin excretion and can be used to identify
albuminuria, a marker of generalized  vascular endothelial damage (Xu et al., 2008, 157157). Values
> 30 mg/g (3.5 mg/mmol) and > 300 mg/g (34 mg/mmol) usually define micro- and
macroalbuminuria,  both of which are associated with increases in CVD incidence and mortality
(Bigazzi  et al.,  1998, 156272; Deckert et al., 1996,  156389; Dinneen  and Gerstein, 1997, 156403;
Gerstein  et al., 2001, 156466; Mogensen, 1984, 156769). Several researchers have called the
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dichotomization of albuminuria into question, observing that there is no threshold below which risk
of cardiovascular and end-stage kidney disease disappears (Forman and Brenner, 2006, 156439;
Knight and Curhan, 2003, 179900; Ruggenenti and Remuzzi, 2006, 156933).
      Systolic, diastolic, pulse, and mean arterial blood pressures (SBP; DBF; PP; MAP) in mmHg
have also been used as measures of cardiovascular disease. Franklin et al. (1997, 156446) suggested
that SBP and PP were the only two measures predictive of carotid stenosis in a multivariable analysis
considering all 4 measures, whereas Khattar et al.  (2001, 155896) suggested that their prognostic
significance in hypertensive populations may differ by age, with SBP and PP being most predictive
among those > 60 yr and DBP among those <60 yr old (Khattar et al., 2001, 155896).


7.2.5.1.   Epidemiologic Studies

      O'Neill et al. (2007, 156006) examined the  association of UACR  with PM2.5 and PMi0 among
members of the MESA population described previously (Diez et al., 2008, 156401). For this study of
UACR, which included cross-sectional and longitudinal analyses, the study population was restricted
to a subset of 3,901 participants (mean age = 63 yr; 52% female) with complete covariate, outcome
and exposure data at their first through third exams (2000-2004). In cross-sectional analyses, the
authors found that after adjustment for demographic and clinical characteristics, 10 ug/m3 increases
in 20-yr imputed exposures to PM25 and PMi0 were associated with negligible 0.002 (95% CI:
-0.048 to 0.052) and -0.002 (95% CI:  -0.038 to 0.035) mean differences in baseline log UACR,
respectively. Similarly, small statistically non-significant decreases in the prevalence of
microalbuminuria (defined in this setting as > 25 mg/g) provided little evidence of an effect on renal
function. These largely null cross-sectional findings mirrored those based on the study's shorter-term
(30- and 60-day) PM2.5 and PM10 exposures. Moreover, longitudinal analyses revealed only a weak
association between 3-yr change in  log UACR and 20-yr PMi0 exposure. Evidence of effect
modification by demographic and geographic characteristics  was not apparent in either the cross-
sectional or longitudinal analyses.
      Auchincloss et al. (2008, 156234) focused on automated, oscillometric, sphygmomanometric
measures of blood pressures in mmHg (SBP; DBP; PP; MAP). Like O'Neill (2007,  156006). Diez et
al. (2008,  156401) and Allen et al. (2007, 156006). Auchincloss et al. (2008, 156234) based their
examination on the previously described MESA population. The authors included 5,112 study
participants (age range = 45-84 yr; 52% female) who were free of clinically manifested CVD at their
baseline exam in one of six primarily  urban U.S. locations (2000-2002). In this cross-sectional study,
they used  arithmetic averaging of EPA AQS PM2.5 data available at the monitor nearest to each
participant's geocoded U.S. Postal Service ZIP code centroid to estimate 30- and 60-day  avg
exposures to PM25. They found small nonsignificant increases of 1.5 (95% CI: -0.2 to 3.2), 0.2
(95% CI: -0.7 to 1.0), 1.3  (95% CI:  0.1 to 2.6), and 0.6 (95% CI: -0.4 to 1.7) mmHg increases in
SBP, DBP, PP and MAP, respectively, per  10 (ig/m3 increase in 30-day avg PM25 exposure,
Associations were slightly weaker for 60-day avg  PM2 5 exposure and among participants without
hypertension, during cooler weather, in the presence of low NO2, residing >300 m from a highway,
or surrounded by lower road density.
      Finally, the Calderon-Garciduenas et al. (2007, 091252) ecologic study introduced in
Section 7.2.3.1 also found that children residing in Mexico City had higher mean pulmonary artery
pressure as assessed by Doppler echocardiography and fasting plasma endothelin-1 (ET-1) than
residents in Polotitlan: unadjusted mean 17.5 (95% CI: 15.7-19.4) versus 14.6 (95% CI: 13.8-15.4)
mmHg and 2.23 (95% CI: 1.93-2.53)  versus 1.23 (95% CI: 1.11-1.35) pg/mL, respectively. Within
Mexico City, ET-1 was higher in residents of the Northeast (historically  higher PM25) than those of
the Southwest (historically lower PM25).
      The MESA analyses of UACR (O'Neill et al., 2007, 156006) and the ecologic study of
children living in a highly polluted area of Mexico (Calderon-Garciduenas et al., 2007, 091252)
provide little evidence that long-term exposure to  PM2 5 had an effect on renal and vascular function,
respectively. Auchincloss  et al. (2008, 156234) reports small  nonsignificant associations  of blood
pressure with 30- and 60-day avg PM2 5 concentrations. PM concentrations from the analyses are
characterized in Table 7-1.
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Table 7-1.    Characterization of ambient PM concentrations from studies of subclinical measures of
             cardiovascular diseases and long-term exposure.
          Study
Location
Mean Concentration (ug/m
MESA: Multi-Ethnic Study of Atherosclerosis
HNRS: Heinz Nixdorf Recall Study
VEAPS: Vitamin E Atherosclerosis Progression Study
BVAIT: B-Vitamin Atherosclerosis Intervention Trial
   Upper Percentile
Concentrations (ug/m3
PM10
Diez Roux et al. (2008, 1564011
O'Neill et al. (2007, 1560061
Baccarelli et al. (2008, 157984)
Rosenlund et al. (2006, 0897961
Chen and Swartz (2008, 190106)
Forbes et al. (2009, 1903511
MESA: 6 Cities U.S.
MESA: 6 Cities U.S.
Lombardy Region Italy
Stockholm, Sweden
US Population (NHANES)
British Population
20 yr imputed mean: 34
Long-Term Exposure:
1982-2002: 34.7
1982-1987: 40.5
1988-1992: 38
1993-1997: 30.6
1998-2002: 29.7
Previous Month: 27.5
NR
30-yavgPMio (traffic)
Cases: 2.6
Controls: 2.4
Annual avg: 36.8
1994: 19.5 (median)
1998: 17.9 (median)
2003: 16.2 (median)
NR
NR
NR
5th-95th %: 0.5-6
0.6-5.9
NR
1994, Min-Max: 12.5-36.1
1998, Min-Max: 12.6-27.0
2003, Min-Max: 11. 0-22.7
PM2.5
Hoffmann etal.(2007, 091163)
Allen et al. (2009, 1562091
Kunzli et al. (2005, 0873871
Auchincloss et al. (2008, 1562341
O'Neill (2007, 1560061
Diez Roux et al. (2008, 156401)
Hoffmann et al. (2009, 190376)
Calderon-Garciduenas et al. (2009,
1921071
Calderon-Garciduenas et al. (2007,
0912521
HNRS, 3 Cities Germany
MESA: 5 Cities
VEAPS BVAIT
MESA: 6 Cities
MESA: 6 Cities U.S.
MESA: 6 Cities U.S.
HNRS: 3 Cities Germany
Southwest Mexico (high pollution)
Potitlan (low pollution)
Southwest Mexico (high pollution)
Potitlan (low pollution)
Annual avg: 22.8
Annual avg: 15.8
Annual avg: 20.3
Prior 30 days: 16.8
Prior 60 days: 16.7
Previous Month: 16.5
20-y imputed mean: 21.7
Annual avg: 22.8
Annual avg: 25
Annual avg: <15
NR
NR
NR
Min-Max: 10.6-24.7
Min-Max: 5.2-26.9
NR
NR
NR
Min-max: 19.8-26.8
NR
NR
NR
NR
7.2.5.2.   Toxicological Studies

      In a PM2.5 CAPs study of 10 wk (6 h/day><5 days/wk) in Tuxedo, NY (mean mass
concentration 79.1  ug/m3), there was no difference in mean arterial pressure (MAP) in SD rats
between groups (Sun et al., 2008,  157032). When angiotensin II (Ang II) was infused during the last
week of exposure to induce systemic hypertension, the MAP slope was consistently greater in the
CAPs-exposed rats compared to the filtered air group. Furthermore, thoracic aortic rings were more
responsive to phenylephrine-induced constriction and less responsive to ACh-induced relaxation in
the PM+Ang II vessels. In contrast to the latter findings, the relaxation response was exaggerated in
the PM+Ang II aortic segments with a Rho-kinase (ROCK) inhibitor. Superoxide production in
aortic rings increased in the PM+Ang II group compared to the filtered air group and the addition of
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NAD(P)H oxidase inhibitor (apocynin) or aNOS inhibitor (L-NAME) attenuated the superoxide
generation. The levels of tetrahydrobiopterin (BH4) were decreased in mesenteric vasculature and the
heart by 46% and 41% in the PM+Ang II group compared to controls, respectively; furthermore,
levels of BH4 in the liver were similarly reduced, which is consistent with a systemic effect of CAPs.
Together, these findings indicate that CAPs potentiate Ang II-induced hypertension and alter
vascular reactivity, perhaps through activated NADPH oxidase and eNOS uncoupling that result in
oxidative stress generation and triggering of the Rho/ROCK signaling pathway.


7.2.6.  Autonomic Function
7.2.6.1.   lexicological Studies

      Hwang et al. (2005, 087957) and Chen and Hwang (2005, 087218) used radiotelemetry to
examine the chronic changes in HR and HRV resulting from the same CAPs exposures described
previously (Chen  and Nadziejko, 2005, 087219). The overall average CAPs exposure concentration
was 133 ug/m3 and results indicate differing responses to CAPs between ApoE"" mice and their
genetic background strain, C57BL/6J mice (Hwang et al., 2005, 087957). Using the time period of
1:30-4:30 a.m., C57BL/6J mice showed a HR increase only over the last month of exposure. In
contrast, ApoE"7" mice had chronic decreases of 33.8 beat/min for HR. Changes in HRV (SDNN and
rMSSD) were somewhat more complicated, with biphasic responses in ApoE"7" mice over the
5-month period (initial increase over first 6 wk, decrease over next 12 wk, and slight upward turn for
remainder of the study)(Chen  and Hwang, 2005, 087218).  Increasing linear trends were observed in
C57BL/6J mice for SDNN and rMSSD. The average CAPs concentration for the HRV study was
110 ug/m3. However, only three C57BL/6J mice in the exposure group were included in the analysis
compared to ten ApoE"" animals, thus making it difficult to interpret the C57BL/6J mice responses
(Chen and Hwang, 2005, 087218; Hwang et al., 2005, 087957).


7.2.7. Cardiac changes



7.2.7.1.   Toxicological studies

      Two recent toxicological studies have evaluated the effects of PM on  cardiac effects including
pathology and gene expression. Cardiac mitochondrial function has also been evaluated following
PM exposure in rats.


      Diesel Exhaust

      A recent study of DE exposure (PM mass concentration 507 or 2,201  ug/m3, CO 1.3 or
4.8 ppm,  NO <2.5 or 5.9 ppm, NO2 O.25 or 1.2 ppm, SO2 0.2 or 0.3 ppm for low and high PM
exposures, respectively; geometric median number diameter 85 nm) indicated a hypertensive-like
cardiac gene expression in WKY rats that mimicked baseline patterns in air-exposed SH rats
(Gottipolu et al., 2009, 190360). Exposure to the high concentration of DE for 4 wk (4 h/day,
5 day/wk) led to downregulation of genes involved in stress, antioxidant compensatory response,
growth and extracellular matrix regulation, membrane transport of molecules, mitochondrial
function,  thrombosis regulation, and immune function. No  genes were affected by DE in SH rats. A
dose-dependent inhibition of mitochondrial aconitase activity in both rat strains was observed,
indicating a DE effect on oxidative stress. It should be noted that while DE-related cardiovascular
effects were found in WKY rats only, pulmonary inflammation  and injury were observed in both
strains (Sections 7.3.3.2 and 7.3.5.1).
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      Model Particles

      Wallenborn et al. (2008, 191171) examined the subchronic (5 h/day, 3 day/wk, 16 wk)
pulmonary, cardiac, and systemic effects of nose-only exposure to particulate ZnSO4 (9, 35, or
120 ug/m ) in WKY rats. Particle size was reported to be 31-44 nm measured as number median
diameter. Although changes in pulmonary inflammation or injury and cardiac pathology were not
observed, effects on cardiac mitochondrial protein and enzyme levels were noted (i.e., increased
ferritin levels, decrease in succinate dehydrogenase activity), possibly indicating a small degree of
mitochondrial dysfunction. Glutathione peroxidase, an antioxidant enzyme, was also decreased in
the cardiac cytosol. Gene expression analysis identified alterations in cardiac genes involved in cell
signaling events, ion channels regulation, and coagulation in animals exposed to the highest ZnSO4
concentration only. This study demonstrates a possible direct effect of ZnSO4 on extrapulmonary
systems, as suggested by the lack of pulmonary effects (Section 7.3.3.2).


7.2.8.  Left Ventricular Mass and Function

      Van Hee et al. (2009, 192110) studied 3,827 participants (age range = 45-84 yr; 53% female)
who underwent magnetic resonance imaging (MRI) of the heart at the baseline examination of the
MESA cohort (2000-2002). This cross-sectional study focused on two MRI-based outcome
measures: left ventricular mass index (LVMI, g/m2) and ejection fraction (EF, %), the former
estimated using the DuBois formula for body surface area, the latter as the ratio of stroke volume to
end diastolic volume. The study also estimated annual mean exposures to PM2.5 at participants'
geocoded residential addresses in 2000 using ordinary kriging of U.S. EPA AQS concentration data.
In fully adjusted  models, it found 3.8 (95% CI: -6.1 to 13.7) g/m2 and -3.0% (-8.0 to 2.0) differences
in LVMI  and EF  per 10 (ig/m3 increment in PM2.5. The findings were small and imprecise, albeit
suggestive of a slight, PM-associated increase in the mass and decrease in the function of the left
ventricle. The effect of living within 50 m of a major roadway on LVMI was greater than the effect
of PM2.5 (i.e., 1.4 g/m2 [95% CI:  0.3-2.5] per 10  ug/m3.)


7.2.9. Clinical Outcomes  in  Epidemiologic Studies

      Several epidemiologic studies of U.S. and European populations have examined associations
between long-term PM exposures and clinical CVD events (Baccarelli et al., 2008, 157984;
Hoffmann et al.,  2006, 091162: Hoffmann et al., 2009, 190376: Maheswaran et al., 2005, 088683:
Maheswaran et al., 2005, 090769: Miller et al., 2007, 090130: Rosenlund et al., 2006, 089796:
Solomon et al., 2003, 156994: Zanobetti and Schwartz, 2007, 091247).  Results from these studies
are summarized in Figure  7-1. The ambient PM concentrations from these studies are characterized
in Table 7-2.


      Coronary Heart Disease

      Epidemiologic studies examining the association of coronary heart disease (CHD) with long-
term PM  exposure are discussed  below (Hoffmann et al., 2006, 091162: Maheswaran et al., 2005,
090769: Miller et al., 2007, 090130: Puett et al., 2008, 156891: Rosenlund et al., 2006, 089796:
Rosenlund et al., 2009, 190309: Zanobetti and Schwartz, 2007, 091247). Cases of CHD were
variably defined  in these studies to include history of angina pectoris, MI, coronary artery
revascularization (bypass graft; angioplasty; stent; atherectomy),  and congestive heart failure (CHF).
Results pertaining to death from  CHD are described in Section 7.6.
      Miller et al. (2007, 090130) studied incident, validated MI, revascularization, and CHD death,
both separately and collectively, among 58,610 post-menopausal  female residents of 36 U.S.
metropolitan areas (age range = 50-79 yr) enrolled in the Women's Health Initiative Observational
Study (WHI OS, 1994-1998). In this prospective cohort study of participants free of CVD at baseline
(median duration of follow-up =  6 yr), the authors used arithmetic averaging of year 2000 EPA AQS
PM2.5 data available at the monitor nearest to each participant's geocoded U.S.  Postal Service five-
digit ZIP code centroid to  estimate  1-yr avg exposures. They found  6% (95% CI: -15 to 34), 20%
(95%  CI: 0-43) and 21% (95% CI:  4-42) increases in the overall risk of MI, revascularization, and
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their combination with CHD death per 10 ug/m3 increase in PM2.5, respectively. Hazards were higher
within than between cities and in the obese. For the combined CVD outcome (MI, revascularization,
stroke, CHD death, cerebrovascular disease), authors reported a 24% (95% CI: 9-41) increase in risk
that was higher among participants at higher than lower quintiles of body mass index, waist-to-hip
ratio, and waist circumference. The PM2.5-CVD association was stronger among non-diabetic than
diabetic participants.


Table 7-2.   Characterization of ambient PM concentrations from studies of clinical cardiovascular
            diseases and long-term exposure.
           Study
Location
   Mean Annual
Concentration (ug/m )
  Upper Percentile
Concentrations (ug/m
PM10
Puett et al. (2008, 156891)
Zanobetti and Schwartz (2007, 091247)
Rosenlund et al. (2006, 0897961
Rosenlund et al. (2009, 1903091
Maheswaran et al. (2005, 0907691
Baccarelli et al. (2008, 1579841
13 U.S. States
21 U.S. Cities
Stockholm, Sweden
Stockholm, Sweden
Sheffield, U.K.
Lombardia Region, Italy
21.6
28.8
30 yavgPM10 (traffic)
Cases: 2.6
Controls: 2.4
5-yravg PM10 from traffic:
Cases: 2.4 (median)
Controls: 2.2 (median)
Range of means in each quintile: 16-23.3
NR

Overall range NR
5th-95th Percentile
0.5-6.0
0.6-5.9

NR
NR
PM2.5
Miller etal. (2007, 090130)
Hoffmann et al. (2006, 0911621
Hoffman et al. (2009, 1903761
WHI: 36 Metropolitan areas
HNRS: 2 Cities Germany
HRNS: 2 Cities German
Citywideavg(yr2000): 13.5
23.3
22.8
Min-max: 4-19.3
NR
NR
WHI: Womens Health Initiative
HNRS: Hans Nixdorf Recall Study


      Puett et al. (2008, 156891) studied incident, validated CHD, CHD death, and non-fatal MI
among 66,250 female residents (mean age = 62 yr) of metropolitan statistical areas in thirteen
northeastern U.S. states who were enrolled in the Nurses' Health Study (NHS, 1992-2002). In this
prospective cohort study of women without a history of non-fatal MI at baseline (maximum duration
of follow-up = 4 yr), the authors used two-stage, spatially smoothed, land use regression to estimate
residence-specific, 1-yr ma PMi0 exposures from U.S. EPA AQS and emissions, IMPROVE, and
Harvard University monitor data. They found a 10% (95% CI: -6 to 29) increase in risk of first CHD
event per  10 u/m3 increase in 1-yr avg PMi0 exposure, while the association with MI was close to the
null value. The association with fatal CHD event of 30% (95% CI: 0-71) was stronger. Furthermore,
associations with CHD death were higher in the obese and in the never smokers.
      Rosenlund et al. (2006, 089796) studied 2,938 residents of Stockholm County, Sweden (age
range = 45-70 yr; 34%  female). In this case-control study of 1,085 patients with their first, validated
non-fatal MI and an age-, gender- and catchment-stratified random sample of 1,853 controls without
MI (1992-1994), the authors used street canyon-adjusted dispersion modeling of emissions data to
estimate 30-yr avg exposure to PMi0 (median = 2.4 ug/m3). They found that the OR for prevalent MI
per 10 ug/iri increase in PM10 was 0.85 (95% CI: 0.50-1.42). The OR for fatal MI was elevated, but
not statistically significant.
      In a more recent  study, Rosenlund et al. (2009, 190309)  evaluated 554,340 residents (age
range = 15-79 yr; 49%  female) of Stockholm County, Sweden (1984-1996). In this population-based,
case-control study of 43,275 cases of incident, validated MI, the authors used dispersion modeling  of
traffic emissions and land use data to estimate 5-yr avg exposure to PMi0. They found that after
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adjustment for demographic, temporal, and socioeconomic characteristics, the OR for MI per
5 ug/m3 increase in PMi0 was 1.04 (95% CI: 1.00-1.09). ORs were higher after restriction to fatal
cases, in- or out-of-hospital deaths, and participants who did not move between population censuses.
Authors state that control for confounding was superior in their previous study (Rosenlund et al.,
2006, 089796) although the size of the population was larger in this recent study (Rosenlund et al.,
2009, 190309).
       Zanobetti and Schwartz (2007, 091247) studied ICD-coded recurrent MI (ICD 9 410)  and
post-infarction CHF (ICD 9  428) among 196,131 Medicare recipients (age > 65 yr; 50% female)
discharged alive following MI hospitalization in 21 cities from 12 U.S.  states (1985-1999). In this
ecologic, open cohort study of re-hospitalization among MI survivors (mean duration of follow-
up =  3.6 and 3.7 yr for MI and CHF, respectively), the authors used arithmetic averaging of EPA
AQS PMio data available in the county of hospitalization to estimate  1-yr avg  exposures. They found
17%  (95% CI: 5-31) and 11%  (95% CI: 3-21) increases in the risk of recurrent MI and post-
infarction CHF, respectively, per 10 ug/m3 increase in PMi0 exposure. Hazards were somewhat
higher among persons aged >75  yr.
       Hoffmann et al. (2006, 091162) studied self-reported CHD (MI or revascularization) among
3,399 residents of Essen and Mulheim, Germany (age range = 45-75 yr; 51% female) at the baseline
exam of the Heinz Nixdorf Recall Study (2000-2003) introduced previously. In this cross-sectional
ancillary study, the authors used dispersion modeling of emissions, climate and topography data to
estimate 1-yr avg exposure to PM2.5 (mean = 23.3 ug/m3). They found little evidence of an
association between PM2.5 and CHD in these data. After adjustment for geographic, demographic
and clinical characteristics, the OR for prevalent CHD per 10 ug/m3 increase in exposure was 0.55
(95% CI: 0.14-2.11).
Study
Avg Time  Endpoint
Effect Estimate (95% CI)
Prospective Cohort Studies
Miller etal.(2007,090130)
  58,610 post-menopausal women enrolled in WHI,
  incident, validated cases, 36 US cities
Puettetal. (2008.156891)
  75,809 women in the Nurses Health Study,
  validated cases, 13 metro areas, NE states

Case Control Studies
Rosenlund et al. (2009,190X9)
  24,347 cases, N=276,926 randomly selected
  population based controls, Stockholm, Sweden
Rosenlund et al. (2006,089796)
  2,246 cases, N=3,206 randomly selected
  population controls, Stockholm, Sweden
Baccarelli et al. (2008,157984)
  871 cases, N=1210 healthy friend controls,
  Lombardy, Italy
Other Study Designs
Hoffman etal. (2006.091162)
Hoffman et al. (2009,190376)
  Prevalent cases at baseline in 3,399 residents,
  cross-sectional, 2 German cities
Zanobetti & Schwartz (2007,091247)
  196,131 Ml survivors (ICD9410), readmitted for
  Ml or CHF, ecologic, open cohort, 21 US cities

Maheswaran et al. (2005,090769:2005,088683)
  Hospital admissions among 199,682 residents,
  ecologic design, Sheffield, UK
   1 yr    Incident Ml
         Revascularization
         Stroke
         Cerebrovascular Disease
         All CVD

   1yr    1st CHD Event



   Syr    Fatal/Non-Fatal Ml


  30 yr    Fatal/Non-Fatal Ml


   1 yr    DVT
   1 yr    Self-reported CHD
   1 yr    Self-reported PVD
   1 yr    Recurrent Ml Hospitalization
         Post-Mi CHF Hospitalization
   5 yr    CHD Hospitalization
         Stroke Hospitalization
                            PM,
                             PM,C
                             PM,,
                            PMZ
                             PM,,
                                                        I  I  i \  I  I  I I  I  I  I I  I  I  I I  I  \  \ I  I  I  I  I I
                                                       0,0  0,2 0.4  0,6 0.8  10 1.2  1.4 1,6  1.8 2,0  2.2 2.4
                                                                Relative Risk Estimate
Figure 7-1.     Risk estimates for the associations of clinical outcomes with long-term exposure
                to ambient PM2.s and PMio.
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      In the study of 1,030 census enumeration districts in Sheffield, U.K. described previously,
Maheswaran et al. (2005, 090769) studied 11,407 ICD-10-coded emergency hospitalizations for
CHD (ICD10 120-25) among 199,682 residents (age > 45 yr; 45% female). In this ecologic study, the
authors used dispersion modeling of emissions and climate data to estimate 5-yr avg exposure to
PMio. They found that after adjusting for smoking prevalence, controlling for socioeconomic factors,
and smoothing, the age- and gender-standardized rate ratios for CHD admission were 1.01 (95% CI:
0.92-1.11), 1.04 (95% CI: 0.93-1.15), 0.97 (95% CI: 0.87-1.08), and 1.07 (95% CI: 0.95-1.20) across
PMio quintiles. The linear trend was somewhat stronger for CHD mortality (Section 7.3).
      The study of post-menopausal women enrolled in the WHI OS by Miller et al. (2007, 090130)
was the only U.S. study to examine the effect of PM2.5 rather than PMi0. This study, which provides
strong evidence of an association, was distinguished by its prospective cohort design, validation of
incident cases  and large population. Puett et al. (2008, 156891).  the other U.S. study with
comparable  design features, provides evidence of an association of incident CHD with long- term
PMio exposure. Findings from Swedish case control studies of incident validated cases of MI were
not consistent. A cross-sectional study of self-reported CHD did not provide evidence of an
association with PM25> while findings from two ecologic studies of PMio indicated positive
associations of CHD  hospitalizations with PMio (Maheswaran et al., 2005, 088683; Zanobetti and
Schwartz, 2007, 091247).


      Stroke

      Miller et al. (2007, 090130) found 28% (95% CI: 2-61) and 35% (95% CI: 8-68) increases in
the overall risk of validated stroke and cerebrovascular disease, respectively, per 10 ug/m3 increase
in 1-yr avg PM2.5 exposure.  Risks were higher within than between cities. In the study of 1030
Census of enumeration districts in Sheffield, U.K. described previously, Maheswaran et al. (2005,
088683) studied 5,122 ICD-10-coded emergency hospital admissions for stroke (160-69) among
199,682 residents (age > 45 yr; 45% female) of 1,030 census enumeration districts in Sheffield, U.K.
(1994-1999). In this ecologic study, the authors used dispersion  modeling of emissions and climate
data to estimate 5-yr  avg exposure to PMi0. They found that the  age- and gender-standardized rate
ratios for stroke admission were 1.05 (95% CI: 0.94-1.17), 1.07  (95% CI: 0.95-1.20), 1.06 (95% CI:
0.94-1.20), and 1.15 (95% CI: 1.01-1.31) across PMio quintiles.  Linear trend was somewhat stronger
for stroke mortality (Section 7.6).
      These studies examining the long-term PM-stroke relationship provide evidence of
association.  Maheswaran et al.  (2005, 088683) examined emergency room hospital admissions in
Sheffield, U.K. using an ecologic design while results reported by Miller et al. (2007, 090130) are
based on the prospective cohort study of the WHI OS population (both introduced previously).


      Peripheral Arterial Disease

      The German Heinz Nixdorf Recall cross-sectional study described in Section 7.2.1.1
(Hoffmann et al., 2009, 190376) also evaluated the association between 1-yr avg exposure to PM2.5
and peripheral arterial disease (self-reported history of a surgical or procedural intervention or an
ABI <0.9 in one or both legs). The authors found no evidence of an increase in risk. The OR for
peripheral arterial disease was 0.87 (95% CI: 0.57-1.34) per 3.9  ug/m3  increase in PM25. However,
evidence of an association with traffic exposure was present in these data. ORs of 1.77 (95% CI:
1.01-3.10), 1.02 (95% CI: 0.58-1.80), and 1.07 (95% CI: 0.68-1.68) for residing < 50, 50-100, and
100-200 m of a major road (reference category: >200 m), respectively were observed. ORs were
higher among participants with CAC scores < 75th percentile, women, and smokers.


      Deep Vein Thrombosis

      The Italian case-control study (introduced in Section 7.2.1.2) also examined the chronic PM10-
DVT  association (Baccarelli et al., 2008  157984). The authors found a 70% (95% CI: 30-223)
increase in the odds of DVT per 10 ug/m increase in 1-yr avg PMio exposure. This finding was
consistent with the decreases in PT and PTT also observed among controls in this context as well as
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the 47% (95% CI: 11-96) increase in the odds of DVT per inter-decile range (242 m) increase in the
residence-to-major-roadway distance observed among a subset of cases and controls (Baccarelli et
al., 2009, 188183). The PMi0-DVT and distance-DVT associations were both weaker among women
and among users of oral contraceptives or hormone therapy.


7.2.10.Cardiovascular Mortality

      New epidemiologic evidence reports a consistent association between long-term exposure to
PM2.5 and increased risk of cardiovascular mortality. There is little evidence for the long-term effects
of PMio_2.5 on cardiovascular mortality. This section focuses on cardiovascular mortality outcomes in
response to long-term exposure to PM. The studies that investigate long-term exposure and mortality
due to any specific or all (nonaccidental) causes are evaluated in Section 7.6. A summary of the
mean PM concentrations reported for the studies characterized in this section is presented in Table
7-8, and the effect estimates are presented in Figure 7-7 and Figure 7-8.
      A number of large, U.S. cohort studies have found consistent associations between long-term
exposure to PM2.5 and cardiovascular mortality. The American Cancer Society (ACS) (Pope et al.
(2004, 055880) reported positive associations with deaths from specific cardiovascular diseases,
particularly ischemic heart disease, and a group of cardiac conditions including dysrhythmia, heart
failure and  cardiac arrest (RR for cardiovascular mortality = 1.12 [95% CI: 1.08-1.15] per 10 ug/m3
PM25). In an additional reanalysis that extended the follow-up period for the ACS cohort to 18 yr
(1982-2000) (Krewski et al., 2009, 191193), investigators found effect estimates that were similar,
though generally higher, than those reported in previous ACS  analyses.
      A follow-up to the Harvard Six Cities study (Laden et al., 2006, 087605) used updated air
pollution and mortality data and found positive associations between long-term exposure to PM2.5
and mortality. Of special note is a statistically significant reduction in mortality risk reported with
reduced long-term fine particle concentrations. This reduced mortality risk was observed for deaths
due to cardiovascular and respiratory causes, but not for lung cancer deaths.
      The WHI cohort study (Miller et al., 2007, 090130) (described previously) found that each
10 ug/m3 increase of PM2.5 was associated with a 76% increase in the risk of death from
cardiovascular disease (hazard ratio, 1.76  [95% CI: 1.25-2.47]). The WHI study not only confirms
the ACS and Six City Study associations with cardiovascular mortality in yet another well
characterized cohort with detailed individual-level information, it also has been able to consider the
individual medical records of the thousands of WHI subjects over the period of the study. This has
allowed the researchers to examine not only mortality, but also related morbidity in the form of heart
problems (cardiovascular events) experienced by the subjects  during the study. These morbidity co-
associations with PM2 5 in the same population lend even greater support to the biological
plausibility of the air pollution-mortality associations found in this study.
      In an analysis for the Seventh-Day Adventist cohort in California (AHSMOG), a positive
association with coronary heart disease mortality was reported among females (92 deaths; RR = 1.42
[95% CI: 1.06-1.90] per 10 ug/m3 PM2.5), but not among  males (53 deaths; RR = 0.90 [95% CI:
0.76-1.05] per 10 ug/m3 PM25) (Chen et al., 2005, 087942). Associations were strongest in the subset
of postmenopausal women (80 deaths; RR = 1.49 [95% CI: 1.17-1.89]  per  10 ug/m3 PM2.5). The
authors speculated that females may be more sensitive to air pollution-related effects, based on
differences between males and females in dosimetry and exposure. As was found with PM2 5, a
positive association with coronary heart disease mortality was reported for PMi0_2 5 and PMi0 among
females (RR = 1.38 [95% CI: 0.97-1.95] per 10 ug/m3 PM10.25;RR = 1.22 [95% CI: 1.01-1.47] per
10 ug/m3 PM10), but not for males (RR = 0.92 [95% CI: 0.66-1.29] per 10 ug/m3 PM10.2.5; RR = 0.94
[95% CI: 0.82-1.08] per 10 ug/m3 PMio);  associations were strongest in the subset of
postmenopausal women (80 deaths) (Chen et al., 2005, 087942).
      Two  additional studies explored  the effects of PM10 on cardiovascular mortality. The Nurses'
Health Study (Puett et al., 2008, 156891) is an ongoing prospective cohort  study examining the
relation of chronic PMi0 exposures with all-cause mortality and incident and fatal coronary heart
disease consisting of 66,250 female nurses in MS As in the northeastern region of the U.S. The
association with fatal CHD occurred with the greatest magnitude when compared with other
specified causes of death (hazard ratio  1.42 [95% CI: 1.11-1.81]). The North Rhine-Westphalia State
Environment Agency (LUANRW) initiated a cohort of approximately 4,800 women, and assessed
whether long-term exposure to air pollution originating from motorized traffic and industrial sources
was associated with total and cause-specific mortality (Gehring et al., 2006, 089797). They found
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that cardiopulmonary mortality was associated with PM10 (RR = 1.52 [95% CI: 1.09-2.15] per
10 ug/m3PMi0).
      In summary, the 2004 PM AQCD concluded that there was strong evidence that long-term
exposure to PM2.5 was associated with increased cardiopulmonary mortality. Recent studies
investigating cardiovascular mortality provide some of the strongest evidence for a cardiovascular
effect of PM. A number of large cohort studies have been conducted throughout the U.S. and
reported consistent increases in cardiovascular mortality  related to PM2.5 concentrations. The results
of two of these studies have been replicated in independent reanalyses. These effects are coherent
with short-term epidemiologic studies of CVD morbidity and mortality and with long-term
epidemiologic studies of CVD morbidity.  In addition, biological plausibility and coherence are
provided by toxicological studies demonstrating short-term cardiovascular effects as well as
PM2.5-related plaque progression in chronically  exposed  mice.


7.2.11.Summary  and Causal Determinations



7.2.11.1.  PM2.5

      Epidemiologic studies examining associations between long-term exposure to ambient PM
(over months to years) and CVD morbidity had not been conducted and thus were not included in the
1996 or 2004 PM AQCDs (U.S. EPA, 1996, 079380; U.S. EPA, 2006, 157071). A number of studies
were included in the 2004 AQCD that evaluated the effect of long-term PM2.5 exposure  on
cardiovascular mortality and found strong and consistent associations. No toxicological studies had
evaluated the effects of subchronic or chronic PM exposure on CVD  effects in the 2004 PM AQCD.
Recently, epidemiologic and toxicological studies have provided evidence of the adverse effects of
long-term exposure to PM2 5 on cardiovascular outcomes and endpoints, including atherosclerosis
and clinical and subclinical markers of cardiovascular morbidity.
      The strongest evidence for a CVD health  effect related to long-term PM2 5 exposure comes
from epidemiologic studies of cardiovascular mortality. A number of large, multicity U.S. studies
(the ACS, Six Cities Study, WHI, and AHSMOG) provide consistent evidence of an effect between
long-term exposure to PM25 and cardiovascular mortality (Section 7.2.10). These studies were
conducted in urban areas across the U.S. where  mean concentrations  ranged from 10.2-29.0 (ig/m3
(Table 7-8). An epidemiologic study investigating the relationship between PM2 5 and clinical CVD
morbidity among post-menopausal women (Miller et al., 2007, 090130) provides evidence of an
effect that is coherent with the cardiovascular mortality studies. This  large, prospective cohort study
of incident, validated cases found large increases in the adjusted risk  of MI, revascularization,  and
stroke using a 1-yr avg PM25 concentration (mean = 13.5 ug/m3). A cross-sectional  analyses of self-
reported prevalence of CHD and peripheral arterial disease found no  such increase in the odds of
CVD morbidity (Hoffmann et al., 2006, 091162); the inconsistency of these findings with Miller et
al. (2007, 090130) may be explained by differences in study design or location.
      The effect of long-term PM25 exposure on pre-clinical measures of atherosclerosis (CIMT,
CAC, AAC or ABI) has been studied in several  populations using a cross-sectional  study design. The
magnitude of the PM25 effects and their consistency across different measures of atherosclerosis in
these studies varies widely, and they may be limited in their ability to discern small changes in these
measures. Kunzli et al. (2005, 087387) observed anon-significant 4.2% increase in CIMT associated
with long-term PM2 5 exposure among participants of a clinical trial in greater Los Angeles, which
was several fold higher than the 0.5% increase observed  by Diez-Roux et al. (2008, 156401) in their
analyses of MESA baseline data. The  associations in MESA of CAC  and ABI with long-term PM25
exposure were largely null (Diez et al., 2008,  156401), while an increase in AAC with long-term
PM2 5 exposure was reported (Chang et al., 2008, 180393). By contrast, a 43% increase  in CAC was
associated with long-term PM2 5 exposure  in a German study, but no similar association with ABI
was observed (Hoffmann et al., 2009, 190376). Although the number of studies examining these
relationships is limited, effect modification by use of lipid lowering drugs and smoking  status was
reported in more than one study of long-term PM25 and PMi0 exposure.
      Evidence of enhanced atherosclerosis development was demonstrated in new toxicological
studies that report increased plaque and lesion areas, lipid deposition, and TF in aortas of ApoE"7"
mice exposed to CAPs (Section7.2.1.2). In addition, alterations in vasoreactivity were observed,
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suggesting an impaired NO pathway. Additional toxicological studies of PM10 are consistent with
these results. Further support is provided by a study that reported decreased LAV ratio in the
pulmonary and coronary arteries of mice exposed to ambient air. However, PM2.5 CAPs derived from
traffic in Los Angeles did not affect plaque size (Araujo et al., 2008,  156222). Collectively, these
toxicological studies provide biological plausibility for the associations reported in epidemiologic
studies.
     There is limited evidence for the effects of PM2.5 on renal or vascular function. Cross-sectional
and longitudinal epidemiologic analyses of PM2.5 and UACR revealed no evidence of an effect
(O'Neill et al., 2007, 156006). while small non-statistically significant increases in BP with 30- and
60-day avg PM25 concentrations were reported (Auchincloss et al., 2008, 156234). A toxicological
study did not show changes in MAP with CAPs, but indicated a CAPs-related potentiation of
experimentally-induced hypertension (Sun et al., 2008, 157032). In addition, CAPs has induced
changes in insulin resistance, visceral adiposity, and inflammation  in a diet-induced obesity mouse
model (Sun et al., 2009, 190487), indicating that diabetics may be  a potentially susceptible
population to  PM exposure.
     In summary,  a number of large U.S. cohort studies report associations of long-term PM25
concentration with  cardiovascular mortality. These studies provide the strongest evidence for an
effect of long-term PM25  exposure on CVD effects. Additional evidence comes from a
methodologically rigorous epidemiology study that demonstrates coherent associations between
long-term PM2 5 exposure and CVD morbidity among post-menopausal women. Toxicological
studies demonstrate that this effect is biologically plausible and the effect is coherent with studies of
short-term PM2 5 exposure and CVD morbidity and mortality, and with long-term exposure to PM2 5
and CVD mortality. Associations between PM2 5 and subclinical measures of atherosclerosis are
inconsistent, but cross-sectional studies may be limited in their ability to discern small changes in
these measures. In addition, potential modification of the PM25-CVD association by smoking status
and the use of lipid lowering drugs has been demonstrated in epidemiologic studies that used
individual-level data. Toxicological studies provide evidence for accelerated development of
atherosclerosis in ApoE"" mice exposed to CAPs and show effects  on coagulation factors,
experimentally-induced hypertension, and vascular reactivity. Available studies of clinical
cardiovascular disease outcomes report inconsistent results. Based on the above findings, the
epidemiologic and toxicological evidence  is sufficient to infer a  causal relationship between
long-term PM2.5 exposures and cardiovascular effects.


7.2.11.2.  PM10.2.5

     One epidemiologic study evaluated the relationship between long-term exposure to PMi0_2.5
and cardiovascular mortality and found a positive association with coronary heart disease mortality
among females, but not for males; associations were strongest in the  subset of post-menopausal
women (Chen et al., 2005, 087942). No toxicological studies of long-term exposure to ambient
PM10_2.5 and cardiovascular effects have been conducted to date. Evidence is inadequate to infer
the presence or absence of a causal relationship.


7.2.11.3.  UFPs

     A few toxicological studies of long-term exposure to UFPs have been conducted. Increased
plaque size was reported in mice exposed to UF CAPs derived from traffic (Araujo et al., 2008,
156222). Studies of diesel and gasoline exhaust reported relatively few changes in hematologic or
coagulation parameters (Section 7.2.4.2) and one DE study demonstrated altered cardiac gene
expression in  normotensive rats that reflected the development of hypertension (Gottipolu et al.,
2009, 190360). Whole and filtered gasoline exhaust induced increases in gene products involved in
atheromatous plaque formation and/or degradation, but these effects were largely due to the gaseous
emissions (Lund et al., 2007, 125741).  Evidence from these studies alone is inadequate to infer
the presence or absence of a causal relationship
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7.3.  Respiratory Effects
      Several cohort studies reviewed in the 2004 PM AQCD provided evidence for relationships
between long-term PM exposure and effects on the respiratory system, though it did not rule out the
possibility that the observed respiratory effects may have been confounded by other pollutants. In 12
southern California communities in the Children's Health Study (CHS), Gauderman et al. (2000,
012531; 2002, 026013) found that decreases in lung function growth among schoolchildren were
associated with long-term exposure to PM. Declines in pulmonary function were reported with all
three major PM size classes - PMi0, PMi0_2.5 and PM2.5 - though the three PM measures were highly
correlated. In another analysis of data from the CHS cohort, McConnell et al. (1999, 007028).
reported an increased risk of bronchitis symptoms in children living in communities with higher
PMio and PM2.5 concentrations. These results were found to be consistent with results of cross-
sectional analyses of the 24-city study by Dockery et al. (1996, 046219) and Raizenne et al. (1996,
077268). that were assessed in the 1996 PM AQCD. These studies reported associations between
increased bronchitis rates and decreased peak flow with fine particle sulfate and fine particle acidity.
However, the high correlation of PMi0, acid vapor and NO2 precluded clear attribution of the
bronchitis effects reported by McConnell et al. (1999, 007028) to PM alone. In a prospective cohort
study among a subset of children in the CHS (n = 110) who moved to other locations during the
study period, Avol et al. (2001, 020552) reported that those subjects who  moved to areas of lower
PMio showed increased growth in lung function compared with subjects who moved to communities
with higher PMio concentrations. Finally, the 2004 PM AQCD concluded that there was strong
epidemiologic evidence for associations between long-term exposures to  PM2 5 and cardiopulmonary
mortality, though the respiratory effects were not separated from the cardiovascular effects  in this
conclusion.
      The 2004 PM AQCD (U.S. EPA, 2004, 056905) concluded that the evidence for an association
between long-term exposure to PM and respiratory effects may be confounded by other pollutants.
Gauderman et al. (2002, 026013) reported declines for FEVi and McConnell et al. (1999, 007028)
reported increased ORs for bronchi tic symptoms in asthmatics for PMio and PM2 5. Recent
epidemiologic literature includes results from several prospective cohort  studies, which found
consistent, positive associations between long-term exposure to  PM and respiratory morbidity.
Associations were reported with PM2 5 and PMio, and the studies showing associations only with
PMio were conducted in locations where the PM consisted predominantly of fine particles,  providing
support for associations with long-term exposure to fine particles. These results  are summarized
below; further details of these studies are summarized in Annex  E.
      Very few subchronic and chronic toxicological studies investigating respiratory effects were
available in the 2004 PM AQCD. However, the 2002 EPA Health Assessment Document for DE
reported that chronic exposure to DE was associated with histopathology including alveolar
histiocytosis,  aggregation of alveolar macrophages, tissue inflammation,  increased
polymorphonuclear leukocytes, hyperplasia of bronchiolar and Type 2 epithelial cells, thickened
alveolar septa, edema, fibrosis, emphysema and lesions of the trachea and bronchi. Since then a
number of animal toxicological studies have been conducted involving inhalation exposure to CAPs,
urban air, DE, gasoline exhaust, and wood smoke. These subchronic and  chronic studies provide
evidence of altered pulmonary function, inflammation,  histopathological  changes and oxidative and
allergic responses following PM2 5 exposures. These results  are summarized below; further details of
these studies are summarized in Annex D.


7.3.1. Respiratory Symptoms and Disease Incidence



7.3.1.1.   Epidemiologic Studies

     New longitudinal cohort studies provide the best evidence to evaluate the relationship between
long-term exposure to ambient PM and increased incidence of respiratory symptoms or disease. A
summary of the mean PM concentrations reported for the long-term exposure studies characterized
in this section is presented in Table 7-3.
December 2009                                  7-20

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      Bayer-Oglesby et al. (2005, 086245) examined the decline of ambient pollution levels and
improved respiratory health demonstrated by a reduction in respiratory symptoms and diseases in
school children (n = 9,591) in Switzerland. Reduced air pollution exposure resulted in improved
respiratory health of children. Further, the average reduction of symptom prevalence was more
pronounced in areas with stronger reduction of air pollution levels. The average decline of PMi0
between 1993 and 2000 across the nine study regions was 9.8 (ig/m  (29%). Declining levels of PMi0
were associated with declining prevalence of chronic cough, bronchitis, common cold, nocturnal dry
cough, and conjunctivitis symptoms, but no significant associations were reported for wheezing,
sneezing, asthma, and hay fever, as shown in Figure 7-2. In Figure 7-2, Panel (B) illustrates that on
an aggregate level across regions, the mean change in adjusted prevalence of chronic cough is
associated with the mean change in PMio levels (r = 0.78; p = 0.02).  Similar associations were seen
for nocturnal dry cough and conjunctivitis symptoms and PMio levels. Roosli et al. (2000, 010296;
2001, 108738; 2005, 156923) have demonstrated that PM10 levels are homogeneously distributed
within regions of Basel, Switzerland and are not substantially affected by local traffic, justifying the
single-monitor approach for assignment of PMi0 exposures. Based on parallel measurements of
PM2.5 and PMio at seven sites in Switzerland, PM2 5 and PMio at all sites are generally highly
correlated (r2 ranging from 0.85 to 0.98) (Gehrig and Buchmann, 2003, 139678). indicating that
PMio consists predominantly of fine particles in these locations.
      Schindler et al. (2009,  191950) reported that sustained reduction in ambient PM10
concentrations can lead to decreases in respiratory symptoms among Swiss adults in the SAPALDIA
study. They compared baseline data in 1991 to a follow-up interview in 2002 after a substantial
decline in PMio concentrations served as a natural experiment. Each  subject was assigned model-
based estimates of PMio concentrations averaged over the 12 mo preceding each health assessment
with mean decline in PMi0 levels of 6.2 (ig/m (SD = 3.9 (ig/m3). When the authors tested the joint
hypothesis  of no association between the PM10 difference and symptom incidence or persistence,
positive results were obtained for regular cough, chronic cough or phlegm and wheezing but not
regular phlegm or wheezing without a cold.
      Pierse et al. (2006,  088757) studied the association between primary PMio (particles directly
emitted from local sources/traffic) and the prevalence and incidence  of respiratory symptoms in a
randomly sampled cohort of 4,400 children (aged 1-5 yr) in Leicestershire, England surveyed in
1998 and again in 2001. Annual exposure to primary PMio was calculated for the home address
using the Airviro statistical dispersion model. After adjusting for confounders, mean annual exposure
to locally generated PMio was associated with an increased prevalence of cough without a cold in
both the 1998 (OR 1.21 [95% CI: 1.07-1.38], n = 2,164) and 2001 surveys (OR 1.56 [95% CI:
1.32-1.84], n= 1,756).
      Nordling et al. (2008, 097998) examined the relationship between estimated PM exposure
levels and respiratory health effects in a Swedish birth cohort of preschool children (n = 4,089). The
spatial distributions of PM from traffic in the study area were estimated with emission databases and
statistical dispersion modeling. Children were examined at 2 mo and 1, 2,  and 4 yr of age. Using GIS
methods, the average contribution of traffic-generated PMio above regional background to the
children's residential outdoor air pollution levels was determined. To evaluate the exposure
assessment, the authors compared the estimated levels of traffic-generated PMio with PM2.5
measurements from 42  locations (Hoek et al., 2002, 042364) and reported modeled traffic-generated
PMio correlated reasonably well with measured PM2.5 (r = 0.61).  Persistent wheezing (cumulative
incidence up to age 4 yr)  was associated with exposure to traffic-generated PMio (OR 2.28 [95% CI:
0.84-6.24] per 10 ug/m3 increase) while transient and late onset wheezing was not associated. This
study demonstrates that respiratory effects may be present in preschool children.
December 2009                                  7-21

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Table 7-3.     Characterization of ambient PM concentrations from studies of respiratory
              symptoms/disease and long-term exposures.
Study
Location
Mean Annual Concentration (ug/m3)
Upper Percentile
Concentrations
(ug/m3)
PM2.5
Annesi-Maesano et al. (2007, 0931801
Braueretal. (2007, 0906911
Cosset al. (2004, 055624)
Islam et al. (2007, 090697)
Janssen et al. (2003, 1335551
Kim et al. (2004, 0873831
McConnell et al. (2003, 049490)
Morgenstern et al. (2008, 1567821
6 French Cities
The Netherlands
U.S.
12 CHS/CA communities
The Netherlands
San Francisco, CA
12 CHS/CA communities
Munich, Germany
Range of means across sites: 8.7-23.0
Avg of means across sites: 15.5
16.9
13.7

20.5
Range of means across sites: 11-15
Avg of means across sites: 12
13.8
11.1

75th: 18.1
90th: 19.0
Max: 25.2
75th: 15.9
Max: 29.5
75th: 22.1
Max: 24.4

Max: 28.5

PM10
Bayer-Oglesby et al. (2005, 0862451
Kunzli et al. (2009, 1919491
Nordling et al. (2008, 097998)
Schindleretal. (2009, 191950)
McConnell et al. (2003, 049490)
Pierse et al. (2006, 0887571
Nine study regions in Switzerland
Switzerland
Sweden
Switzerland
12 CHS/CA communities
Leicestershire, U.K.

21.5
4*
**
30.8
1.33
Max: 46



Max: 63.5
75th: 1.84
*Source specific; PM10 from traffic
**0nly reported change in PM concentration
December 2009
7-22

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             c
             o
             0)
             E
            ^»
            T3
             V
             3

            ^
                                                                        Source: Bayer-Oglesby et al. (2005, 0862451

Figure 7-2.     Adjusted ORs and 95% CIs of symptoms and respiratory diseases associated
               with a decline of 10 ug/m3 PMio levels in Swiss Surveillance Program of
               Childhood Allergy and Respiratory Symptoms1.  Inset: Mean change in adjusted
               prevalence (1998-2001 to 1992-1993) versus mean change in regional annual
               averages of PM™ (1997-2000 to 1993) for chronic cough, across nine SCARPOL
               regions (An: Anieres. Be: Bern. Bi: Biel. Ge: Geneva. La:, Langnau. Lu: Lugano.
               Mo: Montana. Pa: Payerne. Zh: Zurich).

      McConnell et al. (2003, 049490) conducted a prospective study examining  the association
between air pollution and bronchitic symptoms in 475 school children with asthma in 12 Southern
California communities as part of the CHS from 1996 to 1999. They investigated  both the
differences between- communities with 4-yr avg and within-communities yearly variation in PM
(i.e., PMio, PM25, PMio_25, EC, and OC). Based on a 10 ug/m3 change in PM25, within-communities
effects were larger (OR 1.90 [95% CI: 1.10-2.70]) than those for between-communities (OR 1.30
[95% CI: 1.10-1.50]). The OR for the  10 ug/m3 range in 4-yr avg PM25 concentrations across the  12
communities was 1.29 (95% CI:  1.06-1.58). Similar results were reported for PMi0 and PMi0_2.5 but
the effect estimates were smaller in magnitude and generally not statistically significant. Within-
community associations  were not confounded by any time-fixed personal covariates. In two-
1 Adjusted for age, sex, nationality, parental education, number of siblings; farming status, low birth weight, breastfeeding, child who
 smokes, family history of asthma, bronchitis, and/or atopy, mother who smokes, indoor humidity, mode of heating and cooking,
 carpeting, pets allowed in bedroom, removal of carpet and/or pets for health reasons, person who completed questionnaire, month when
 questionnaire was completed, number of days with the maximum temperature <0°C, and belief of mother that there is an association
 between environmental exposures and children's respiratory health
December 2009
7-23

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pollutant models, the within-community effect estimates for PM2.5 and OC were significant in the
presence of several other pollutants. While the within-community single-pollutant effect of PM2.5
(B = 0.085/ug/m3) was only modestly attenuated after adjusting for some pollutants, it was markedly
reduced after adjusting for NO2 or OC. The between-community effect estimates generally were not
significant in the presence of other pollutants in copollutant models.
      In the CHS, Islam et al. (2007, 090697) examined the hypothesis that ambient air pollution
attenuates the reduced risk for childhood asthma that is associated with higher lung function
(n = 2,057). At each age a distribution of pulmonary functions exists. Haland et al. (2006, 156511)
found evidence that children with high lung function have a reduced risk for asthma. Islam et al.
(2007, 090697) used the CHS data to study how the association of asthma incidence with lung
function is modified by long-term PM exposure. The incidence rate (IR) of newly diagnosed asthma
increased from 9.5/1,000 person-years for children with percent-predicted FEF25_75 values > 120% to
20.4/1,000 person-years for children with FEF25_75 value < 100%. Over the 10th-90th percentile
range for FEF25.75 (57.1%), the hazard ratio of new onset asthma was 0.50 (95% CI: 0.35-0.71). The
IR of asthma for FEF25_75> 120% in the "high" PM2.5 (13.7-29.5 (ig/m3) communities was 15.9/1,000
person-years compared to 6.4/1,000 person-years in "low" PM25 (5.7-8.5 (ig/m3) communities. Loss
of protection by high lung function against new onset asthma in the "high" PM25 communities was
observed for all the lung function measures. Figure 7-3 shows the effect of PM25 on the association
of lung function with asthma.  Of all the pollutants examined (NO2, PM10, PM25, acid vapor, O3, EC,
and OC), PM2 5 appeared to have the strongest modifying effect on the association between lung
function with asthma as it had the highest R2 value (0.42). Over the 10th-90th percentile range of
FEF25_75, the hazard ratio of new onset asthma was 0.34 (95% CI: 0.21-0.56) in a community with
low PM2.5 (<13.7 ug/m3) and 0.76 (95% CI: 0.45-1.26) in a community with high PM2.5
(> 13.7 ug/m3). The data do not indicate that PM exposure increased rates of incident asthma among
children with poor lung function at study entry because rates among those with poor lung function
were similar in both low and high pollution communities.
                1.00


                1.50-
                1.20-1
             as
             N
                0.90-
                0.60-


                0.30-


                0.00
                         High PM2 6 - Communities
Low PM2 5
Communities
                                                                        ML
                                                             RV
                             LB
                                                R2 = 0.42
                                                P = 0.01
                                I
                                10
                      I
                     15
 I
20
 I
25
 I
30
                                            PM2.5(Mg/m3)

                            Source: Reprinted with Permission of BMJ Publishing Group Ltd & British Thoracic Society from Islam et al. (2007, 090697'

Figure 7-3.    Effect of PM2.s on the association of lung function with asthma. Community-
              specific hazard ratio of newly diagnosed asthma over 10-90th percentile range
              (57.1%) of FEF25.75%  by level of ambient PM2.5 (ug/m3). The 12  CHS communities
              are shown.

      In a prospective birth cohort study (n = 4,000) in The Netherlands, Brauer et al. (2007,
090691) assessed the development of asthma, allergic symptoms, and respiratory infection during
the first 4 yr of life in relation to long-term PM2 5 concentration at the home address with a validated
model using GIS. PM25 was associated with doctor-diagnosed asthma (OR = 1.32 [95% CI:
December 2009
                       7-24

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1.04-1.69]) for a cumulative lifetime indicator. These findings extend observations made at 2 yr of
age in the same cohort (Brauer et al., 2002, 035192) providing greater confidence in the association.
No associations were observed for bronchitis.
     Kunzli et al. (2009, 191949) used the SAPALDIA cohort study discussed previously in this
section to evaluate the relationship between the 11-yr change (1991-2002) in traffic-related PMi0 and
asthma incidence-adult onset asthma. In a cohort of 2,725 never-smokers without asthma at baseline
(age: 18-60 yr in 1991), subjects reporting doctor-diagnosed asthma at follow-up were considered
incident cases. Modeled traffic-related PMi0 levels were used. Cox proportional hazard models for
time to asthma onset were used with adjustments for cofounders. The study findings suggest that PM
contributes to asthma development and that reductions in PM decrease asthma risk. A strong feature
of SAPALDIA is the ability to assign space, time, and source-specific pollution to each subject.
Further, Kunzli et al. (2008, 129258) discusses the impact of attributable health risk models for
exposures that are assumed to cause both chronic disease and its exacerbations. The added impact of
causing disease increases the risk compared to only exacerbations.
     A matched case-control study of infant bronchiolitis (ICD 9 code 466.1) hospitalization and
two measures of long-term exposure - the month prior to hospitalization (subchronic) and the
lifetime average (chronic) - to PM2.5 and gaseous  air pollutants in the South Coast Air Basin of
southern California was conducted by Karr et al. (2007, 090719) among 18,595 infants born between
1995-2000. For each case, 10 controls matched on date were randomly selected from birth records.
Exposure was based on PM2.5 measurements collected every third day. The mean distance between
the subjects' residential ZIP code and the assigned monitor was generally 4-6 mi with a maximum
distance of 30 mi. For 10 ug/m3 increases in both sub-chronic and chronic PM2.5 exposure, an
adjusted OR of 1.09 (95% CI: 1.04-1.14) was observed. In multipollutant model analyses, the
association with PM2.5 was robust to the inclusion of gaseous pollutants. Also, in a cohort of children
in Germany, Morgenstern et al. (2008, 156782) modeled PM2 5 data at birth addresses found
statistically significant effects for asthmatic bronchitis, hay fever, and allergic sensitization to pollen.
     Goss et al. (2004, 055624) conducted a national study examining the relationship between air
pollutants and health effects in a cohort of cystic fibrosis (CF) patients (n = 11,484) over the age of
6 yr (mean  age = 18.4, SD = 10) enrolled in the Cystic Fibrosis Foundation National Patient Registry
in 1999 and 2000. Exposure was assessed by linking air pollution values from the closest population
monitor from the Air Quality System (AQS) with the centroid of the patient's home ZIP code that
was within  30 mi. The mean distance from the patient's ZIP code to monitors for PM2 5 and PMi0
was 10.8 mi (SD 7.8) and 11.5  mi (SD 7.9), respectively. PM2.5 and PMi0 24-h avg were collected
every 1 to 12 days. CF diagnosis involves genetic screening panels and a common severe mutation
used is the loss of phenylalanine at the 508th position. Genotyping was available in 74% of the
population and of those genotyped, 66% carried one or more delta F508 deletions. After adjusting for
confounders, a 10 ug/m increase in PM25 or PM10 was associated with a 21% (95% CI: 7-33) or 8%
(95% CI: 2-15) increase in the odds of two or more exacerbations, respectively. The exacerbations
were defined as a CF-related pulmonary condition requiring admission to the hospital or use of home
intravenous antibiotics. The estimate for the associations between pulmonary exacerbations and
PM25 and PMi0 were attenuated when the models were adjusted for lung function. Brown et al.
(2001, 012307) found that particle deposition was increased in CF and that particle distribution in
the lungs was enhanced in poorly ventilated tracheobronchial regions in CF patients. Such focal
deposition may partially explain the association of PM and CF exacerbation.
     Annesi-Maesano (2007, 093180) relate individual data on asthma and allergy from 5,338
school children (10.4 ± 0.7 yr)  attending 108 randomly chosen schools in 6 French cities to the
concentration of PM25 monitored in school yards. Atopic asthma was related to PM25 (OR 1.43
[95% CI: 1.07-1.91]) when high PM2.5 concentrations (20.7 ug/m3) were compared to low PM2.5
concentrations (8.7 ug/m3). The report is consistent with the results in an earlier paper (Penard-
Morand et al., 2005, 087951) in the same sample of children that related the findings to PMi0.
     Kim et al. (2004, 087383) conducted a school-based cross-sectional study in the San Francisco
metropolitan area in 2001 comprised of 10 neighborhoods to examine the relationship between
traffic-related pollutants and current bronchitic symptoms and asthma obtained by parental
questionnaire (n = 1,109). They related traffic-related pollutants (PM) and bronchitic and asthma
symptoms in the past 12 mo. No multipollutant models were evaluated because of the high
interpollutant correlations. PM25 levels ranged across the school sites from 11 to 15 ug/m3.
     Schikowski et al. (2005,  088637) examined the relationship between both long-term air
pollution exposure and living close to busy roads and COPD in the Rhine-Ruhr Basin of Germany
December 2009                                 7-25

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from 1985 to 1994 using consecutive cross-sectional studies. Seven monitoring stations that were
<8 km to a woman's home address provided TSP data that PMi0 was estimated from using a
conversion factor (obtained from parallel measurement of TSP and PMi0 conducted at 7 sites in the
Ruhr area). Distance to a major road was determined using GIS. The results of the study suggest that
long-term exposure to air pollution from PMi0 and living near a major road might increase the risk of
developing COPD and can have a detrimental effect on lung function. All ORs for 5-yr exposures
were stronger than those for 1-yr exposures.
      In summary, the 2004 PM AQCD evaluated the available studies which primarily related
effects to bronchitic symptoms in school-age children. New studies are using several different
methods to include individual estimates of exposure to ambient PM that may reduce the impact of
exposure error. The strength and consistency of the outcomes is enhanced by results being reported
by several different researchers in different countries using different designs. Most recent studies
have focused on children, but a few studies have also reported associations in adults.
      The CHS (McConnell et al., 2003, 049490) provides evidence in a prospective longitudinal
cohort study that relates PM2.s and bronchitic symptoms and reports larger associations for within-
community effects that are less subject to confounding than between-community effects. Several
new studies report similar findings with long-term exposure to PMi0 in areas where fine particles are
the predominant fraction of PMi0. In England,  in a cohort of 4,400 children (aged 1-5 yr), an
association is seen with an increased prevalence of cough without a cold. Further evidence includes a
reduction of respiratory symptoms corresponding to decreasing PM levels in "natural experiments"
in both a cohort of Swiss school children (Bayer-Oglesby et al., 2005, 086245) and adults (Schindler
etal, 2009, 191950).
      In a separate analysis of the CHS, Islam et al. (2007, 090697) showed that PM2.5 had the
strongest modifying effect on the association between lung function with asthma such that loss of
protection by high lung function against new onset asthma in high PM2.s communities was observed
for all the lung function measures from 10  to 18 yr of age. This relates new onset asthma to long-
term PM exposure. In the Netherlands, Brauer et al. (2007, 090691) augments the literature with data
examining the first 4 yr of life in a birth cohort showing an association with doctor-diagnosed
asthma. Further, in an adult cohort in the SALPALDIA study, Kunzli et al. (2009, 191949) relate PM
to asthma incidence.


7.3.2.  Pulmonary Function

      Several cohort studies reviewed in the 2004 PM AQCD provided evidence for relationships
between long-term PM exposure and effects on the respiratory  system. In 12 southern California
communities in the Children's Health Study (CHS), Gauderman et al. (2000, 012531: 2002, 026013)
found that decreases in lung function growth among school children were associated with long-term
exposure to PM. Declines in pulmonary function  were reported with all three major PM size classes
- PMio, PMio_2.5 and PM2.5 - though the three PM measures were highly correlated. These results
were found to be consistent with results of cross-sectional analyses of Raizenne et al. (1996,
077268). that was assessed in the 1996 PM AQCD. That study reported associations between
decreased peak flow with fine particle sulfate and fine particle acidity. Finally, in a prospective
cohort study among a subset of children in the CHS (n = 110) who moved to other locations during
the study period, Avol et al. (2001,  020552) reported that those subjects who moved to areas of lower
PMio showed increased growth in lung function compared with subjects who moved to communities
with higher PMio concentrations who showed decrease growth in lung function.


7.3.2.1.   Epidemiologic Studies

      New longitudinal cohort studies have evaluated the relationship between long-term exposure
to PM and changes in measures of pulmonary function (FVC, FEVi, and measures of expiratory
flow). Cross-sectional studies also offer supportive information (Annex E) and may provide insights
derived from within community analysis. Lung function increases continue through early adulthood
with growth and development, then declines with aging (Stanojevic et al., 2008, 157007; Thurlbeck,
1982, 093260; Zeman and Bennett, 2006,  157178). A summary of the mean PM concentrations
reported for the long-term exposure studies characterized in this section is presented in Table 7-4.
December 2009                                 7-26

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Table 7-4.    Characterization of ambient PM concentrations from studies of FEVi and long-term
             exposures.
         Study
Location
   Mean Annual
Concentration (ug/m3)
  Upper Percentile
Concentrations (ug/m3)
PM2.5
Gauderman et al. (2002, 0260131
                        12 CHS/CA communities
                                                5-30
Gauderman et al. (2004, 0565691
                        12 CHS/CA communities
                                                6-27
Cosset al. (2004, 0556241
                        U.S.
                                                13.7
                                                                        75th: 15.9
                                                Range of means across sites: 3.7-44.7
Gotschi et al. (2008, 1803641
21 European cities
Avg of mean across sites: 16.8

PM10
Downs et al. (2007, 0928531
Gauderman et al. (2002, 0260131
Gauderman et al. (2004, 0565691
Nordling et al. (2008, 097998)
Avoletal. (2001,020552)
Rojas-Martinez et al. (2007, 0910641
8 cities in Switzerland
12 CHS/CA communities
12 CHS/CA communities
Sweden
Southern CA/CHS
Mexico City, Mexico
Range of means across sites: 9-46
Avg of mean across sites: 21.6
Range of means across sites: 13-78
Avg of mean across sites: NR
Range of means across sites: 18-68
Avg of mean across sites: NR
Modeled exposure
Range of means across sites: 15.0-66.2
75.6





75th: 92.2
90th: 112.7
      The CHS prospectively examined the relationship between air pollutants and lung function
(FVC, FEVi, MMEF) in a cohort (n = 1,759) of children between the ages of 10 and 18 yr, a period
of rapid lung development (Gauderman et al., 2004, 056569). Air pollution monitoring stations
provided data in each of the 12 study communities from 1994-2000. The results for C^PM^NO^
PM2.5, acid vapor, and EC are depicted in Figure 7-4. In general, copollutant models for any pair of
pollutants did not provide a substantially better fit to the data than the corresponding single-pollutant
models due to the strong correlation between most pollutants. The pollution-related deficits in the
average growth in lung function over the 8-yr period resulted in clinically important deficits in
attained lung function at the age of 18.
      Downs et al. (2007, 092853) prospectively examined 9,651 randomly selected adults (18-60 yr
of age) in eight cities in Switzerland (see alsoAckermann-Liebrich et al., 1997, 077537) to ascertain
the relationship between reduced exposure to PM10 and age-related decline in lung function (FVC,
FEVi, and FEF25_5o). An evaluated statistical dispersion model (Liu et al., 2007, 093093) provided
spatially resolved concentrations of PMi0 that enabled assignment to residential addresses for the
participant examinations in 1991 and 2002 that yielded a median decline of 5.3  ug/m3 (IQR 4.1-7.5).
Decreasing PMi0 concentrations attenuated the decline in lung function. Effects were greater in tests
reflecting small airway function. No other pollutant relationships were  evaluated,  though a related
study indicated that levels of NO2 also declined over the same period (Ackermann-Liebrich et al.,
2005, 087826). Generalized cross-validation essentially chose a linear fit for the concentration-
response curve for age-related decline in lung function.
      These data show that improvement in air quality may slow the annual rate of decline in lung
function in adulthood indicating positive consequences for public health. Further evidence on
improvement in respiratory health with reduction in air pollution levels is provided from studies
conducted in East Germany related to dramatic emissions reductions after the reunification in 1990
(Fryer and Collins, 2003, 156454: Heinrich et al., 2002, 034825; Sugiri et al., 2006,  088760). This
type of "natural experiment" provides additional support for epidemiologic findings that relatively
low levels of airborne particles have respiratory effects.
December 2009
              7-27

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 1

 1
         R=0.04
         P-0.89
           LB
                       UP
                       SD
                      _*_
                                                    ID-,
                           * ML
                               • RV
                   » AT
               » LM
                             » AL

                             • LE
                                                 I
                                       LA
                      i-tN-
                                                                          »UP
                                                                                          *ML
      25
              35      45      55       65

                O3 from 10 a.m. to 6 p.m. (ppb)
     10-,
          R-0.75
          P-0.005
                                            75
                                             UP
                                                                   L;N
                                                      10     20     30     40     50      60

                                                                     PM10 (^g/m'l
                                                                                            70
                               ML
                                                 1
                                        »SD
                                                    ID-,
                                                     6-
                                                     4-
                       »LE
                        LN,
                                                                  »LE
                10
                         20

                       N02(ppb)
                                   30
                                            40
 e.  10-,
 I
 "S
                                                           » LN
                                                              10
                                                          R=0.74
                                                          P=0.006
                                                                     15

                                                                     PM2
                                                                             20
                                                                                    25
                                                                                            30
                                                                                      * UP
                                                                                     »SD
                                                                       #LE
                                                                        LN
                   4      6

                     Acid Vapor (ppb)
                                      10     12
Figure 7-4.
                                                      0.0    0.2   0.4    0.6   0.8    1.0   1.2    1.4
                                                                 Elemental Carbon (fg/m3)

                                                                 Source: Adapted from Gauderman et al. (2004, 056569)
                                                          Copyright © 2004 Massachusetts Medical Society. All rights reserved.

               Proportion of 18-yr olds with an FEV1 below 80% of the predicted value plotted
               against the average levels of pollutants from 1994 through 2000  in the 12
               southern California communities of the Children's Health Study. AL = Alpine;
               AT = Atascadero; LA = Lake Arrowhead; LB = Long Beach; LE =  Lake Elsinore;
               LM = Lompoc; LN = Lancaster; ML = Mira Loma; RV = Riverside; SD = San  Dimas;
               SM = Santa Maria; UP = Upland.

      In a prospective cohort study consisting of school-age children (n = 3,170) who were 8  yr of
age at the beginning of the study, had not been diagnosed with asthma, and were located in Mexico
City, Rojas-Martinez et al. (2007, 091064) evaluated the association between long-term exposure to
PMio, O3 and NO2 and lung function growth every 6 mo from April 1996 through May 1999.
Exposure data were provided by 10 air quality monitor stations located within 2 km of each child's
school. The multipollutant model effect of PMi0 over the age of 8-10 yr of life in this cohort on FVC,
FEVi, and FEF 25-75 showed an association. Single pollutant models showed an association between
ambient pollutants (O3, PMi0 and NO2) and deficits in lung function growth. The association
between PM10 and FEF25_75 was not statistically significant. While the estimates from copollutant
models were not substantially different than single pollutant models, independent effects for
pollutants could not be estimated accurately because the traffic-related pollutants were correlated.
December 2009
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Although no PM2.5 data were presented in this study, in a separate study Chow et al. (2002) report
that during the winter of 1997 approximately 50% of PMi0 was in the PM25 fraction in Mexico City.
      Gotschi et al. (2008, 156485) examined the relationship between air pollution and lung
function in adults in the European Community Respiratory Health Survey (ECRHS). FEVi and FVC
were assessed at baseline and after 9 yr of follow-up from 21 European centers (followed-up sample
n = 5,610). No statistically significant associations were found between city-specific annual mean
PM2 5 and average lung function levels which is in contrast to the results seen by Ackermann-
Liebrich (1997, 077537) (SAPALDIA) and Schikowski et al. (2005, 088637) (SALIA) which
compared across far more homogenous populations than for the population assessed in the ECRHS.
Misclassification and confounding may partially explain the discrepancy in findings.
      In a birth cohort (n = 2,170) in Oslo, Norway, Oftedal et al. (2008, 093202) examined effects
of exposure to PM2.5 and PMi0 on lung function (FVC, FEVi, FEF50°/0).  Spirometry was performed in
2,307 children aged 9-10 yr in 2001-2002. Residential air pollution levels over the time period
1992-2002 were calculated using EPISODE dispersion models to provide three time scales of
exposure:  (1) first year of life; (2) lifetime exposure; and (3) just before the lung function test. Only
single pollutant models were evaluated because air pollutants were highly correlated (r = 0.83-0.95).
PM exposure was associated with changes in adjusted peak respiratory  flow, especially in girls. No
effect was found for forced volumes. Adjusting for contextual socioeconomic factors diminished
associations. Results for PMi0 were similar to those for PM2 5.
      In an exploratory study, Mortimer et al. (2008, 187280) examined the association of prenatal
and lifetime exposure to air pollutants using geocoded monthly average PMi0 levels with pulmonary
function in a San Joaquin Valley, California cohort of 232 children (ages 6-11 yr) with asthma. First
and second trimester PMiq exposures (based on monthly average concentrations) had a negative
effect on pulmonary function and may relate to prenatal exposures affecting the  lungs as they begin
to develop at 6-wk gestation.
      Dales et al. (2008, 156378) in a cross-sectional prevalence study  examined the relationship of
pulmonary function and PM measures, other pollutants, and indicators of motor vehicle emissions in
Windsor, Ontario, in a cohort of 2,402 school children. PM25 and PMi0 concentrations were
estimated  for each child's residence at the postal code level. Each 10 ug/m3 increase in PM25 was
associated with a 7.0% decrease in FVC expressed in a percentage of predicted.
      In Leicester, England, investigators examined the carbon content of airway macrophages in
induced sputum in 64 of 114 healthy 8-15 year-old children (Grigg et al., 2008,  156499; Kulkarni et
al., 2006, 089257). The carbon content of airway macrophages (Finch et al., 2002, 054603; Strom et
al., 1990,  157020) was used as a marker of individual exposure to PMip. Near each child's home,
exposure to PMi0 was estimated using a statistical dispersion model (Pierse et al., 2006, 088757).
The authors reported a dose-dependent inverse association between the carbon content of airway
macrophages and lung function in children and found no evidence that reduced lung function itself
causes an  increase in carbon content. Consistent results were obtained for both FVC and FEF25_75.
Caution should be used when interpreting these results as the accuracy of the estimates on individual
PMio exposures were not validated; there is potential for confounding by ethnic  origin; and there is
concern that the magnitude of the changes in pulmonary function associated with increased particle
area appear large (Boushey et al., 2008,  192162).
      Nordling et al. (2008, 097998) discussed above in the respiratory symptoms section, also
reported that lower PEF at age 4 was associated with exposure to traffic-related  PMi0 (-8.93 L/min
[95%  CI: -17.78 to -0.088]). Goss et al. (2004, 055624). discussed in Section 7.3.1.1, found strong
inverse relationships between FEVi and PM25 concentrations in both cross-sectional and
longitudinal analyses.
      In summary, recent studies have greatly expanded the evidence available for the 2004 PM
AQCD. The earlier CHS studies followed young children for 2-4 yr. New analyses have been
conducted that include longer follow-up periods of this cohort through  18 yr of age (considered early
adulthood for lung development (Stanojevic et al., 2008, 157007) and provide evidence that effects
from exposure to PM2 5 persist into early adulthood. Longitudinal studies follow effects over time
and are considered to provide the best evidence as opposed to studies across communities as in
cross-sectional studies. The longitudinal cohort studies in the 2004 PM AQCD provided data for
children in one location in one study and new longitudinal  studies have been conducted in other
locations.
      Gauderman et al. (2004, 056569) reported that PM2 5 exposure was  associated with clinically
and statistically significant deficits in FEVi attained at the age of 18 yr. Clinical significance was
December 2009                                 7-29

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defined as a FEVi below 80% of the predicted value, a criterion commonly used in clinical settings
to identify persons at increased risk for adverse respiratory conditions. This clinical aspect is an
important enhancement over the earlier results reported in the 2004 PM AQCD. Further, the
association reported in this study that evaluated the 8-yr time period into early adulthood not only
provided evidence for the persistence of the effect, but in addition the strength and robustness of the
outcomes were more positive, larger, and more certain than previous CHS studies of shorter follow-
up.
      Supporting this result are new longitudinal cohort studies conducted by other researchers in
other locations with different methods. Though these studies report results for PMi0, available data
discussed above indicate that the majority of PMi0 is composed of PM2.5 in these areas. New studies
provide positive results from Mexico City, Sweden,  and a national cystic fibrosis cohort in the U.S.
One study reported null results in a European cohort described as having potential misclassification
and confounding concerns as well as lacking a homogenous population potentially rendering the
outcome  as non-informative. A natural experiment in Switzerland, where PM levels had decreased,
reported that improvement in air quality may slow the annual rate of decline in lung function in
adulthood, indicating positive consequences for public health. These natural experiments are
considered especially supportive.
      The relationship between long-term PM exposure and decreased lung function is thus seen
during lung growth and lung development in school-age children into adulthood. At adult ages
studies continue to show a relationship between decreased lung function and long-term  PM
exposure. Some newer studies attempting to study the relationship of long-term PM exposure from
birth through preschool are reporting a relationship.  Thus, the impact of long-term PM exposure is
seen over the time period of lung function growth and development and the decline of lung function
with aging.
      Overall, effect estimates from these studies  are negative (i.e., indicating decreasing lung
function) and the pattern of effects are similar between the studies for FVC and FEVi. Thus, the data
are consistent and coherent across several designs, locations, and researchers. With cautions noted,
the results relating carbon content of airway macrophages to decreased measures of pulmonary
function add plausibility to the epidemiologic findings. Some new studies  are using individual
estimates of exposure to ambient PM to reduce the impact of exposure error (Downs et  al., 2007,
092853: Jerrett et al., 2005,  087381).
      As was found in the 2004 PM AQCD, the studies report associations with PM2.5 and PMi0,
while most did not evaluate PMi0_2.5. Associations have been reported with fine  particle components,
particularly EC and OC. Source apportionment methods generally have not been used in these long-
term exposure studies. However, numerous studies have evaluated exposures to PM related to traffic
or motor  vehicle sources. For example, Meng et al. (2007, 093275) investigated the associations
between traffic and outdoor pollution levels and poorly controlled asthma  among adults who were
respondents to the  California Health Interview Survey and found associations for traffic density and
    o, but not PM2.5.
7.3.2.2.   lexicological Studies


      Urban Air

      One new study evaluated the effects of chronic exposure to ambient levels of urban particles
on lung development in the mouse (Mauad et al., 2008, 156743). Both functional and anatomical
indices of lung development were measured. Male and female BALB/c mice were continuously
exposed to ambient or filtered Sao Paolo air for 8 mo. Concentrations in the "polluted chamber"
versus "clean chamber" were 16.8 versus 2.9 (ig/m3 PM25. Thus PM levels were reduced by
filtration but not entirely eliminated. Ambient concentrations of CO, NO2 and SO2 were 1.7 ppm,
89.4 (ig/m3 and 8.1 (ig/m3, respectively. Concentrations of gaseous pollutants were assumed to be
similar to ambient levels in both chambers. After 4 mo, the animals were mated and the offspring
were divided into 4 groups to provide for a prenatal exposure group, a postnatal exposure group, a
pre and postnatal exposure group and a control group. Animals were sacrificed at 15 and 90 days of
age for histological analysis of lungs. Pulmonary pressure-volume measurements were also
conducted in the 90-day-old offspring. Statistically significant reductions in inspiratory and
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expiratory volumes were found in the group receiving both prenatal and postnatal exposure, but not
in the groups receiving only prenatal exposure or only postnatal exposure, compared with controls.
These changes in pulmonary function correlated with anatomical changes which are discussed in
Section 7.3.5.1.


      Diesel Exhaust

      Li et al. (2007, 155929) exposed BALB/c and C56BL/6 mice to clean air or to low-dose DE
(at a PM concentration of 100 (ig/m3) for 7 h/day and 5 days/week for 1, 4 and 8 wk. Average gas
concentrations were reported to be 3.5 ppm CO, 2.2 ppm NO2, and less than 0.01 ppm SO2. Airway
hyperresponsiveness (AHR) was evaluated by whole-body plethysmography at Day 0 and after 1, 4
and 8 wk of exposure. Short-term exposure responses are discussed in Section 6.3.2.3, 6.3.3.3 and
6.3.4.2. The increased sensitivity of airways to methacholine (measured as Penh) seen in C57BL/6
but not BALB/c mice at 1 week was also seen at 4 wk but not at 8 wk. This study suggests that
adaptation occurs during prolonged DE exposure. Influx of inflammatory cells, markers of oxidative
stress and effects of antioxidant intervention were also evaluated (Sections 7.3.3.2 and 7.3.4.1).
Although no attempt was made in this study to determine the effects of gaseous components of DE
on the measured responses, concentrations of gases were very low suggesting that PM may have
been responsible for the observed effects.
      In many animal studies changes in ventilatory patterns are assessed using whole-body
plethysmography, for which measurements are reported as enhanced pause (Penh). Some
investigators report increased Penh as an indicator of AHR, but these are inconsistently correlated
and many investigators consider Penh solely an indicator of altered ventilatory timing in the absence
of other measurements to confirm AHR. Therefore use of the terms AHR or  airway responsiveness
has been limited to instances in which the terminology has been similarly applied by the study
investigators.
      Gottipolu et al. (2009, 190360) exposed WKY and SH rats to filtered air or DE (particulate
concentration 500 and 2,000 fig/m3) for 4 h/day  and 5 days/wk over a 4-wk period. Concentrations
of gases were 1.3 and 4.8 ppm CO, NO <2.5 and 5.9 ppm NO, O.25  and 1.2 ppmNO2, 0.2 and
0.3 ppm SO2for low and high PM exposures, respectively. Particle size, measured as geometric
median number and  volume diameters, was 85 and 220 nm, respectively. No DE-related effects were
found for breathing parameters measured by whole-body plethysmography. Other pulmonary effects
are described in Sections 7.3.3.2 and 7.3.5.1.


      Woodsmoke

      One study evaluated the effects of subchronic woodsmoke exposure on pulmonary function in
Brown Norway rats. Rats were exposed 3 h/day  and 5 days/week for 4 and 12 wk to air or to
concentrated wood smoke from the piny on pine which is native to the U.S. Southwest (Tesfaigzi et
al., 2002, 025575). PM concentrations in the woodsmoke were 1,000 and 10,000 (ig/m  . The
particles in this woodsmoke had a bimodal size distribution with the smaller size fraction (74%)
characterized by a MMAD of 0.405 (im and the larger size fraction (26%) characterized by a
MMAD of 6.7-11.7  (im. Many of these larger particles would not be inhalable by the rat since 8 (im
MMAD particles are about 50% inhalable (Menache et al., 1995, 006533). Concentrations  of gases
were reported to be 15-106.4 ppm CO, 2.2-18.9  ppm NO, 2.4-19.7  ppm NOX and 3.5-13.8 ppm total
hydrocarbon in these exposures. Respiratory function measured by whole-body plethysmography
demonstrated a statistically significant increase in total pulmonary resistance in rats exposed to
1000 (ig/m3 woodsmoke. Additional effects were found at 10,000 (ig/m3. Inflammatory and
histopathological responses were also evaluated (Sections 7.3.3.2 and 7.3.5.1).
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7.3.3.  Pulmonary Inflammation



7.3.3.1.   Epidemiologic Studies

      One epidemiologic study examined the relationship of airway inflammation (eNO) and PM
measures, other pollutants, and indicators of motor vehicle emissions in Windsor, Ontario (Dales et
al., 2008, 156378). This cohort of 2,402 school children estimated PM2.5 and PMi0.2.5 for each child's
residence at the postal code level with an evaluated statistical model (Wheeler et al., 2006, 103905).
Each 10 ug/m3 increase in 1-yr PM25 was associated with a 39% increase in eNO (p = 0.058).
Associations between eNO and PMi0_2.5 were positive but not statistically significant.


7.3.3.2.   lexicological Studies



      CAPs Studies

      A set of subchronic studies involved exposure of normal (C57BL1/6) mice, ApoE"7" and the
double-knockout ApoE"7"/LDLR"7" mice to Tuxedo, NY CAPs for 5-6 month (March, April or May
through September 2003 (Lippmann et al., 2005, 087452). The average PM25 exposure
concentration was 110 ug/m . Animals were fed a normal chow diet during the CAPs exposure
period. No pulmonary inflammation was observed in response to CAPs exposure as measured by
BALF cell counts and histology. The lack of a persistent pulmonary response may have been due to
adaptation of the lung following repeated exposures. In fact, a parallel study examined CAPs-related
gene expression in the double-knockout animals and found upregulation of numerous genes in lung
tissue (Gunnison and Chen, 2005, 087956). An in vitro study conducted simultaneously found daily
variations in CAPs-mediated NF-KB activation in cultured human bronchial epithelial cells,
suggesting that transcription factor-mediated gene upregulation could occur in response to CAPs
(Maciejczyk and Chen, 2005, 087456). It should be noted that significant cardiovascular effects
were observed in these subchronic studies which are discussed in Section 7.2.1.2.
      Araujo et al. (2008,  156222) compared the relative impact of UF (0.01-0.18 um) versus fine
(0.01-2.5 um) PM inhalation in ApoE"7" mice following a 40  day exposure (5 h/day><3 days/wk for 75
total hours). Animals were fed a normal chow diet and exposed to PM from November 3 -December
12, 2005 in a mobile inhalation laboratory that was parked 300 m from the 110 Freeway in
downtown Los Angeles. Particles were concentrated to -440 ug/m3 for PM2 5 exposures and
-110 ug/m3 for the UF exposures, representing a roughly 15-fold increase in concentration from
ambient levels; the number concentration of PM in the fine and UF chambers were roughly
equivalent (4.56xl05 and 5.59xl05 particles/cm3, respectively).  Over 50% of the UFPs were
comprised of OC compared to only 25% for PM25. No major increase in BALF inflammatory cells
was found in response to PM. However UFP exposure resulted in significant cardiovascular and
systemic effects (Section 7.2.1.2).


      Diesel Exhaust

      Gottipolu et al. (2009, 190360) exposed WKY and SH rats to filtered air or DE for 4 wk as
described in Section 7.3.2.2. Previous studies from this laboratory have shown enhanced effects of
PM in SH compared with WKY rats. Although the main focus of this recent study was on DE-
induced mitochondrial oxidative stress and hypertensive gene expression in the heart
(Section 7.2.7.1), some pulmonary effects were also found. Subchronic exposure to DE resulted in a
dose-dependent increase in BALF neutrophils in both rat strains although levels of measured
cytokines were not altered. Histological analysis of lung tissue from rats exposed to the higher
concentration of DE demonstrated accumulation of particle-laden macrophages as well as focal
alveolar hyperplasia and inflammation. Effect on indices of injury are discussed in Section 7.3.5.1.
      Ishihara and Kagawa (2003, 096404) exposed Wistar rats to filtered air and DE containing
200, 1,000 and 3,000 ug/m3 PM for 16 h/day and 6 days/wk for 6,  12, 18 or 24 mo. The mass median
particle diameter was reported to be between 0.3  and 0.5 um. Concentrations of gases ranged from
December 2009                                 7-32

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2.93-35.67 ppmNOx, 0.23-4.57 ppm SO2, 1.8-21.9 ppm CO in the DE exposures. Statistically
significant increases in total numbers of inflammatory cells and neutrophils in BALF were observed
beginning at 6-12 mo of exposure to DE containing 1,000 and 3,000 (ig/m3 PM. When rats were
exposed to DE containing 1,000 (ig/m3 PM, which was filtered to remove PM, the inflammatory cell
response was significantly diminished. These results implicate the PM fraction of DE as a key
determinant of the inflammation. The PM fraction was also found to mediate the increase in protein
levels, the decrease in PGE2 levels and alterations in mucus and surfactant components observed in
BALF (Section 7.3.5.1).
      Li et al. (2007, 155929) exposed BALB/c and C56BL/6 mice to low dose DE as described in
Section 7.3.2.2. for 1, 4 and 8 wk. Increases in numbers of BALF macrophages and total
inflammatory cells were observed in BALB/c mice at  8 wk but not 4 wk of DE exposure. Persistent
increases in numbers of BALF neutrophils and lymphocytes were observed in both strains at 4 and
8 wk of DE exposure. Corresponding increases in BALF cytokines differed between the two strains.
These results should be interpreted with caution since  comparisons were made with Day 0 controls
rather than age-matched controls. No histopathological changes in the lungs were seen at any time
point after DE exposure. This study demonstrated differences in pulmonary responses to low dose
DE between two  mouse strains. AHR, pulmonary inflammation, markers of oxidative stress and
effects of antioxidant intervention were also evaluated (Sections 7.3.2.2 and 7.3.4.1). Although no
attempt was made in this study to determine the effects of gaseous components of DE on the
measured responses, concentrations of gases were very low suggesting that PM may have been
responsible for the observed effects.
      In a study by Hiramatsu et al. (2003, 155846). BALB/c and C57BL/6 mice were exposed to
DE (PM concentrations 100 and 3,000 (ig/m3) for 1 or 3 mo. Concentrations of gases were reported
to be 3.5-9.5 ppm CO, 2.2-14.8 ppm NOX, and less than 0.01 ppm SO2. Modest increases in BALF
neutrophils and lymphocytes were observed in response to DE in  both mouse strains at 1 and 3 mo.
Histological  analysis demonstrated diesel exposure particle-laden alveolar macrophages in alveoli
and peribronchial tissues at both time points. Bronchus-associated lymphoid tissue developed after
3-month exposure to the higher concentration of DE in both mouse strains. Mac-1 positive cells (a
marker of phagocytic activation of alveolar macrophages) were also increased in BALF  of BALB/c
mice exposed to the higher concentration of DE for 1 and 3 mo. Increased expression of several
cytokines and decreased expression of iNOS mRNA was observed in DE-exposed mice at 1 and
3 mo. NF-KB activation was also noted following 1-month exposure to the lower concentration of
DE. No attempt was made in this study to determine the responses to gaseous components of the DE.
      In a study by Reed et al. (2004, 055625). healthy Fisher 344 rats and A/J mice were exposed to
DE (PM concentration = 30, 100, 300 and 1,000 (ig/m3) by whole body inhalation for 6 h/day,
7 days/wk for either 1 week or 6 mo.  Concentrations of gases were reported to be 2.0-45.3 ppm NO,
0.2-4.0 ppmNO2, 1.5-29.8 ppm CO and 8-365 ppb SO2. Short-term responses are discussed in
Section 6.3.3.3 and 6.3.7.2, and sub-chronic systemic effects are presented in Section 7.2.4.1. Six
months of exposure resulted in no measurable effects on pulmonary inflammation. However
numerous black particles were observed within alveolar macrophages after 6 mo of exposure.
      Seagrave et al. (2005, 088000)  evaluated pulmonary responses in male and female CDF
(F-344)/CrlBR rats exposed 6 h/day for 6 mo to filtered air or DE at concentrations ranging from
30-1000 (ig/m3 PM. Concentrations of gases were reported for the highest exposure as 45.3 ppm NO,
4.0 ppm NO2, 29.8 ppm CO and 2.2 ppm total vapor hydrocarbon. No changes in BALF cells were
noted. A small decrease in TNF-a was seen in BALF of female rats exposed to the highest
concentration of DE for 6 mo. Pulmonary injury also was evaluated (Section 7.3.5.1). Thus changes
in BALF markers were modest and gender-specific.


      Woodsmoke

      Seagrave et al. (2005, 088000)  also evaluated pulmonary responses in male and female CDF
(F344)/CrlBR rats exposed 6 h/day for 6 mo to filtered air or hardwood smoke concentrations
ranging from 30-1,000 (ig/m3 PM. Concentrations of gases were reported for the highest exposure as
3.0 ppm CO  and  3.1 ppm total vapor hydrocarbon. A small increase in BALF neutrophils was
observed in male rats exposed to the lowest concentration of hardwood smoke. Female rats exhibited
a decrease in BALF macrophage inflammatory protein-2 (MIP-2) at the highest concentration of
hardwood smoke. Pulmonary injury also was evaluated (Section 7.3.5.1). In general, responses to
December 2009                                  7-33

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hardwood smoke were more remarkable than responses to DE seen in a parallel study. However
these gender-specific responses were modest and difficult to interpret.
     In a study by Reed et al. (2006, 156043). Fisher 344 rats, SHR rats, A/J mice and
C57BL/6 mice were exposed to clean air or hardwood smoke (PM concentrations 30, 100, 300 and
1,000 (ig/m3) by whole body inhalation for 6 h/day, 7 days/wk for either 1 week or 6 mo.
Concentrations of gases ranged from 229.0-14887.6 mg/m3 for CO, 54.9-139.3 (ig/m3 for ammonia,
and 177.6- 3455.0 (ig/m3 nonmethane VOC in these exposures. Short-term responses are discussed
in Section 6.3.7.2 and sub-chronic effects are presented in Section 7.2.4.1. Histological analysis of
lung tissue showed minimal increases in alveolar macrophages. The effects of hardwood smoke on
bacterial clearance are discussed below (Section 7.3.7.2).
     Another study evaluated the effects of subchronic woodsmoke exposure in Brown Norway rats
and is described in detail in Section 7.3.2.2 (Tesfaigzi et al., 2002, 025575). Numbers of alveolar
macrophages in BALF were significantly increased in rats exposed to 1,000 (ig/m3 woodsmoke for
12 wk,  but no changes were seen in numbers of other inflammatory cells. A large percent of BALF
macrophages contained carbonaceous material. Histological analysis of lung tissue showed minimal
to mild inflammation in the epiglottis of the  larynx in rats exposed to both concentrations of
woodsmoke.
     Ramos et al. (2009, 190116) examined the effects of subchronic woodsmoke exposure on the
development of emphysema in guinea pigs. Inflammation is thought to be involved in the
pathogenesis of this form of COPD.  Statistically significant increases in total numbers of BALF cells
were observed in guinea pigs exposed to smoke for 1-7  mo, with numbers of macrophages increased
at 1-4 mo and numbers of neutrophils increased at 4-7 mo. At 4 mo, alveolar mononuclear
phagocytic and lymphocytic peribronchiolar inflammation were observed by histological analysis of
lung tissue. This study is discussed in depth in Section 7.2.5.1.


     Model Particles

     Wallenborn et al.  (2008, 191171) examined the pulmonary, cardiac and systemic effects of
subchronic exposure to particulate ZnSO4. WKY rats were exposed nose-only to 10, 30, or
100 ug/m3UFP of ZnSO4 for 5 h/day and 3 day/wk over a 16-wk period. Particle size was reported
to be 31-44 nm measured as number median diameter. No changes in pulmonary inflammation or
injury were observed although cardiac effects were noted (Section 7.2.7.1). This study possibly
demonstrates a direct effect of ZnSO4 on extrapulmonary systems, as suggested by the lack of
pulmonary effects.


7.3.4.  Pulmonary Oxidative Response



7.3.4.1.  lexicological Studies



     Urban Air

     One new study evaluated the effects of subchronic exposure to ambient levels of urban
particles on the development of emphysema in papain-treated mice (Lopes et al., 2009, 190430).
Since oxidative stress is thought to contribute to the  development of emphysema, 8-isoprostane
levels were measured in lung tissue from the four groups of mice used in this study. A statistically
significant increase in 8-isoprostane, a marker of oxidative stress, was observed in lungs from mice
treated with papain and exposed to ambient air compared with the other groups of mice. This study
is described in greater depth in Section 7.3.5.1.
December 2009                                 7-34

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      Diesel Exhaust

      Li et al. (2007, 155929) exposed mice to low dose DE for 1, 4 and 8 wk as described in
Section 7.3.2.2. Markers of oxidative stress and effects of antioxidant intervention were evaluated in
this model. While HO-1 mRNA and protein were increased in lung tissues of both mouse strains
after 1 week of DE exposure (Section 6.3.4.2), at 8 wk of DE exposure, HO-1 protein levels
remained high in C57BL/6 mice but returned to control values in BALB/c mice. This study
demonstrates differences in pulmonary responses to low dose DE between two mouse strains.
Furthermore, this study suggests that adaptation occurs in BALB/c mice during prolonged DE
exposure since the increase in HO-1 protein seen in both strains at 1 week of exposure was only seen
in C57BL/6 mice at 8 wk. AHR (Section 7.3.2.2) and pulmonary inflammation (Section 7.3.3.2)
were also evaluated. Although no attempt was made in this study to determine the  effects of gaseous
components  of DE on the measured responses, concentrations of gases were very low. This suggests
that PM may have been responsible for the  observed effects.


7.3.5.  Pulmonary Injury



7.3.5.1.   lexicological Studies



      Urban Air

      One new study evaluated the effects of chronic exposure  to ambient levels of urban particles
on lung development in the mouse (Mauad  et al., 2008,  156743). Both functional and anatomical
indices of lung development were measured in mice exposed prenatally and/or postnatally as
described in Section 7.3.2.2. Animals were  sacrificed at 15 and  90 days of age for histological
analysis of lungs. Histological analysis demonstrated the presence of mild foci of macrophages
containing black dots of carbon pigment in  the prenatal  and postnatal exposure group at 90 days. In
addition, the alveolar spaces of 15-day  old mice in the prenatal  and postnatal exposure group were
enlarged compared with controls. Morphometric analysis demonstrated statistically significant
decreases in surface to volume ratio at 15 and 90 days in the prenatal and postnatal exposure group
compared with controls. Since alveolarization is normally complete by 15  days of age, these results
suggest incomplete alveolarization in the 15-day-old group and an enlargement of air spaces in the
90-day-old group. These anatomical changes correlated with decrements in pulmonary function
which are discussed in Section 7.3.2.2.
      Prolonged exposure to low levels of ambient air pollution beginning in early life has been
linked to secretory changes in the nasal cavity of mice, specifically increased production of acidic
mucosubstances (Pires-Neto et al., 2006, 096734). Six-day-old  Swiss mice were continuously
chamber exposed to ambient or filtered Sao Paulo air for 5 mo.  Concentrations in the "polluted
chamber" versus "clean chamber" were (in (ig/m3) 59.52 versus 37.08 for NO2, 12.52 versus 0 for
BC, and 46.49 versus 18.62 for PM2.5. Thus, pollutant levels were reduced by filtration but not
entirely eliminated. Compared to filtered air, exposure to ambient air resulted in increased total
mucus and acidic mucus in the epithelium lining the nasal septum, but no statistically significant
differences in other parameters (amount of neutral mucus, volume proportions of neutral mucus,
total mucus, or nonsecretory epithelium, epithelial thickness, or ratio between neutral and acidic
mucus). The physicochemical properties of mucus glycoproteins are critical to the protective
function of the airway mucus layer. Acidified mucus is more viscous, and is associated with a
decrease in mucociliary transport. Thus acidic mucosubstances  may represent impaired defense
mechanisms in the respiratory tract.
      One new study evaluated the effects of subchronic exposure to ambient levels of urban
particles on the development of emphysema in papain-treated mice (Lopes et al., 2009, 190430).
Emphysema is a form of COPD caused by the destruction of extracellular matrix in the alveolar
region of the lung which results in airspace enlargement, airflow limitation and a reduction of the
gas-exchange area of the lung. Inflammation, oxidative  stress, protease imbalance and apoptosis are
thought to contribute to the development of emphysema. In this study, male BALB/c mice were
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continuously exposed to ambient or filtered Sao Paulo air for 2 mo. Concentrations of PM2.5 in the
"polluted chamber" versus "clean chamber" were 33.86 ± 2.09 versus 2.68 ± 0.38 (ig/m3. Thus
filtration reduced PM levels considerably. Ambient concentrations of CO and SO2 were 1.7 ppm and
16.2 (ig/m3 respectively. No significant difference was observed in the concentrations of NO2 in the
"polluted chamber" versus "clean chamber" (60-80 (ig/m3). Half of the mice were pre-treated with
papain by intranasal instillation in order to induce emphysema. Morphometric analysis of lung tissue
demonstrated a statistically significant increase in mean linear intercept, a measure of airspace
enlargement, in papain-treated mice compared with saline-treated controls exposed to filtered  air.
While exposure to ambient air failed to increase mean linear intercept values in saline-treated mice,
mean linear intercept values were significantly increased in papain-treated mice exposed to ambient
air compared with papain-treated mice exposed to filtered air. A similar pattern of responses was
observed for the volume proportion of collagen and elastin fibers in alveolar tissue, which are
markers of alveolar wall remodeling. Lung immunohistochemical analysis demonstrated an effect of
papain, but not ambient air, on macrophage cell density and matrix metalloproteinase 12-positive
cell density. No differences in caspase-3 positive cells, a marker of apoptosis, were observed
between the four groups of mice. Oxidative stress was evaluated in this model as described in
Section 7.3.4.1. Taken together, results of this study demonstrate that urban levels of PM, mainly
from traffic sources, worsen protease-induced emphysema in an animal model.
     Pulmonary vascular remodeling, measured by a decrease in the lumen to wall ratio, was
observed in mice exposed to ambient Sao Paulo air for 4 mo (Lemos et al., 2006, 088594). This
study is described in greater detail in Section 7.2.1.2.
     Kato and Kagawa (2003, 089563) exposed Wistar rats to roadside air contaminated mainly
with automobile emissions (55.7-65.2 ppb NO2 and 63-65 (ig/m3 suspended PM [SPM]) and
examined the effects  on respiratory tissue after 24, 48, or 60 wk of exposure. The surface of the
lungs was light gray in color after all durations of exposure, and BC particle deposits accumulated
with prolonged exposure. These characteristics were not evident in filtered air-exposed control
animals, although filtered air contained low levels of air pollutants (< 6.2 ppb NO2 and 15 (ig/m3
SPM).  The most common change observed using transmission electron microscopy was the presence
of particle laden (anthracotic) alveolar macrophages, or anthracosis, in a wide  range of pulmonary
tissues, including the submucosa, tracheal- and bronchiole-associated lymph nodes, alveolar wall
and space, pleura, and perivascular connective tissue. These changes were evident after 24 wk and
increased with duration of exposure. Other changes included increases in the number of mucus
granules in goblet cells, mast cell infiltration (but no degranulation) after 24 wk, increased
lysosomes in ciliated cells, some altered morphology of Clara cells, and hypertrophy of the alveolar
walls after 48 wk. No goblet cell proliferation was observed, but slight, variable acidification of
mucus  granules appeared after 24 and 48 wk and disappeared after 60 wk. Anthracotic macrophages
were seen in contact with plasma cells and lymphocytes in the lymphoid tissue, suggesting immune
cell interaction in the immediate vicinity of particles. Even after 60 wk, no lymph node anthracosis
was  observed in the filtered air group.
     In a post-mortem study  of lung tissues from 20 female lifelong residents of Mexico City, a
high PM locale, histology demonstrated significantly greater amounts of fibrous tissue and muscle in
the airway walls compared to  subjects from Vancouver (Churg et al., 2003, 087899). a city with
relatively low PM levels. Electron microscopy showed carbonaceous aggregates of UFPs, which the
authors conclude penetrate into and are retained in the walls of small airways.  The study shows an
association between retained particles and airway  remodeling in the form of excess muscle and
fibrotic walls. The subjects were deemed suitable for examination based on never-smoker status, no
use of biomass fuels for cooking, no known occupational particle/dust exposure, death by cause
other than respiratory disease, and extended residence in each locale (lifelong for Mexico City and
>20 yr for Vancouver). However, subjects from the two locales were not matched with respect to
ethnicity, sex (20 females from Mexico City versus 13 females and 7 males from Vancouver),  or
mean age at death (66 ± 9 versus 76 ± 11), and other possibly influential factors such as exercise or
diet were not considered.


     Diesel Exhaust

     Gottipolu et al. (2009, 190360) exposed WKY and SH rats to filtered air or DE as described in
Section 7.3.2.2. Previous studies from this laboratory have shown enhanced effects of PM in SH
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compared with WKY rats. Although the main focus of this recent study was on DE-induced
mitochondrial oxidative stress and hypertensive gene expression in the heart (Section 7.2.7.1), some
pulmonary effects were found. Inflammatory effects are described in Section 7.3.3.2. GGT activity
in BALF was increased in both strains in response to the higher concentration of DE. No DE-related
changes were observed in BALF protein or albumin. Histological analysis of lung tissue from rats
exposed to the higher concentration of DE demonstrated accumulation of particle-laden
macrophages as well as focal alveolar hyperplasia and inflammation. No effects on indices of
pulmonary function were observed (Section 7.3.2.2.)
      Ishihara and Kagawa (2003, 096404) exposed rats to DE for up to 24 mo as described in
Section 7.3.3.2. A statistically significant increase in BALF protein was observed at 12 mo of
exposure to DE containing 1,000 ug/m3 PM.  This response was attenuated when the DE was filtered
to remove PM. Pulmonary inflammation was noted and is described in Section 7.3.3.2.
      Seagrave et al. (2005, 088000) evaluated pulmonary responses in rats exposed to DE for up to
6 mo as described in Section 7.3.3.2.  A small increase in LDH was seen in BALF of female rats
exposed to the highest concentration  of DE for 6 mo. Pulmonary inflammation was also evaluated
(Section 7.3.3.2). The changes in BALF markers in this study were modest and gender-specific.


      Gasoline Exhaust

      Reed et al. (2008, 156903) examined a variety of health effects following subchronic
inhalation exposure to gasoline engine exhaust. Male and female CDF  (F344)/CrlBR rats, SHR rats
and male C57BL/6 mice were exposed  for 6 h/day and 7 days/wk for a period of 3 days-6 mo. The
dilutions for the gasoline exhaust were  1:10,  1:15 and 1:90; filtered PM was at the 1:10 dilution. PM
mass ranged from 6.6 to 59.1 ug/m3,  with the corresponding number concentration between 2.6><104
and 5.0><105 particles/cm3. Concentrations of gases ranged from 12.8-107.3 ppm CO, 2.0-17.9 ppm
NO, 0.1-0.9 ppmNO2, 0.09-0.62 ppm SO2 and 0.38-3.37 ppmNH3. Other effects are described in
Sections 7.2.4.1 and 7.3.6.1. No pulmonary inflammation or histopathological changes were noted in
the F344 rats and A/J mice, except for a time-dependent increase in the number of macrophages
containing PM. However statistically significant increases of 47% and 29% in BALF LDH were
observed in female and male F344 rats, respectively, after 6 mo of exposure to the highest
concentration of engine exhaust. This response was absent when gasoline exhaust was filtered,
implicating PM as a key determinant of this response. In addition, exposure to the highest
concentration of gasoline exhaust resulted in statistically significant decreases in hydrogen peroxide
and superoxide production in unstimulated and stimulated BALF macrophages. Hypermethylation of
lung DNA was observed in male F344 rats following 6 mo of exposure to gasoline exhaust
containing 30 ug/m3 PM. This response was PM-dependent since it was absent in mice exposed to
filtered gasoline exhaust. The significance of this epigenetic change in terms of respiratory health
effects is not known. However, altered patterns of DNA methylation can affect gene expression and
are sometimes associated with altered immune responses and/or the development of cancer.


      Woodsmoke

      Seagrave et al. (2005, 088000) also evaluated pulmonary responses in rats exposed to
hardwood smoke for 6 mo as described in Section 7.3.3.2. Increases in BALF LDH and protein were
seen in male but not female rats. Female rats exhibited a decrease in BALF glutathione at the highest
concentration of hardwood smoke. Decreases in BALF alkaline phosphatase were found in both
males and females exposed to 1,000 ug/m3 hardwood smoke.  Male rats exposed to 100 and
300 ug/m3 hardwood smoke exhibited a decrease in BALF |3-glucuronidase activity. Pulmonary
inflammation was also evaluated (Section 7.3.3.2). These changes in BALF markers in this study
were modest and gender-specific.
      Another study evaluated the effects of subchronic woodsmoke exposure in Brown Norway rats
as described in Section 7.3.2.2. (Tesfaigzi et al., 2002, 025575). Exposure to 1,000 ug/m3
woodsmoke for 12 wk resulted in a statistically significant increase in Alcian Blue- (AB) and
Periodic Acid Schiff- (PAS)  positive  airway epithelial cells compared to controls, indicating an
increase in mucous secretory cells containing neutral and acid mucus, respectively. More significant
histopathological responses were found following exposure to 10,000 ug/m3 of DE. Pulmonary
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function and inflammation were evaluated also but are not discussed here due to the extremely high
exposure level (Sections 7.3.2.2. and 7.3.3.2).
      Ramos et al. (2009, 190116) examined the effects of subchronic woodsmoke exposure on the
development of emphysema in guinea pigs. In particular, the involvement of macrophages and
macrophage-derived MMP in woodsmoke-related responses was investigated. Guinea pigs were
exposed to ambient air or to whole smoke from pine wood for 3 h/day and 5 days/wk over a 7-month
period. PMi0 and PM2.5 concentrations in the exposure chambers were reported to be 502 ± 34 and
363 ± 23 (ig/m3, respectively, while the concentration of CO was less than 80 ppm. COHb levels
were reported to be 6% in controls and 15-20% in smoke-exposed guinea pigs. Statistically
significant decreases in body weight were observed in guinea pigs exposed to smoke for 4 or more
months compared with controls. Statistically significant increases in total numbers of BALF cells
were observed in guinea pigs exposed to smoke for 1-7 mo, with numbers  of macrophages increased
at 1-4 month and numbers of neutrophils increased at 4-7  mo. At 4 mo, alveolar mononuclear
phagocytic and lymphocytic peribronchiolar inflammation, as well as bronchiolar epithelial  and
smooth muscle hyperplasia, were observed by histological analysis  of lung tissue. Emphysematous
lesions, smooth muscle hyperplasia and pulmonary arterial hypertension were noted at 7 mo.
Morphometric analysis  of lung tissue demonstrated statistically significant increases in mean linear
intercept values, a measure of airspace enlargement, in guinea pigs at 6 and 7 mo of exposure.
Statistically significant increases in elastolytic activity was observed in BALF macrophages and lung
tissue homogenates at 1-7 mo of exposure. Lung collagenolytic activity was also  increased at 4-7  mo
of exposure and corresponded in time with the presence of active forms of MMP-2 and MMP-9 in
lung tissue homogenates and BALF. Furthermore, MMP-1 and MMP-9 immunoreactivity was
detected in macrophages, epithelial and interstitial cells in smoke-exposed animals  at 7 mo.
Increased levels of MMP-2 and MMP-9 mRNA were also found in smoke-exposed guinea pigs after
3-7 mo. Apoptosis was found in BALF macrophages (TUNEL assay) from guinea pigs exposed to
smoke for 3-7 mo and in alveolar epithelial cells (caspase-3 immunoreactivity) after 7 mo. Taken
together, these results provide evidence that subchronic exposure to woodsmoke leads to the
development of emphysematous lesions accompanied by the accumulation of alveolar macrophages,
increased levels and activation of MMPs, connective tissue remodeling and apoptosis. However, the
high levels of CO and COHb reported in this study make it difficult to conclude that woodsmoke PM
alone is responsible for these dramatic effects.


7.3.6.  Allergic Responses



7.3.6.1.   Epidemiologic Studies

      A number of epidemiologic studies have found associations between PM and allergic  (or
atopic) indicators. Allergy is a major driver of asthma, which has been associated with PM in studies
discussed in previous sections. In a study by Annesi-Maesano (2007, 093180) (described in
Section 7.3.1.1) atopic asthma was related to PM2.5 (OR 1.43 [95% CI: 1.07-1.91]) and positive skin
prick test to common allergens was also increased with higher PM levels. This report is consistent
with the results from an earlier study (Penard-Morand et al., 2005, 087951) in the same sample of
children that associated allergic rhinitis and atopic dermatitis with PMi0. Also, Morgenstern  et al.
(2008, 156782) found statistically significant effects for asthmatic bronchitis, hay fever, and allergic
sensitization to pollen in a cohort of children in Germany  examining modeled PM2 5 data at birth
addresses. Distance to a main road had a dose-response relationship with sensitization to outdoor
allergens. Nordling et al. (2008, 097998) (discussed above in Section 7.3.2.1) reported a positive
association of PM10 exposure during the first year of life with allergenic sensitization (IgE
antibodies) to inhaled allergens, especially pollen. In a study by Brauer et al. (2007, 090691)
(discussed above in Section 7.3.1.1) an interquartile range increase in PM2.5 was associated with an
increased risk of sensitization to food allergens (OR 1.75  [95% CI 1.23-2.47]). A significant
association was found for sensitization to any allergen, but none was found for sensitization to
specific indoor or outdoor aeroallergens or atopic dermatitis (eczema). In a study by Janssen et al.
(2003, 133555). PM2 5 was associated with allergic indicators such as hay fever (ever), skin prick test
reactivity to  outdoor allergens, current itchy rash, and conjunctivitis in Dutch children. These same
outcomes were also associated with proximity of the school to truck traffic but not car traffic,
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suggesting a role for diesel-related pollution. Consistent with the aforementioned Dutch study by
Brauer et al. (2007, 090691). PM2 5 was not associated with eczema.
      Mortimer et al. (2008, 187280) examined the association between prenatal and early-life
exposures to air pollutants with allergic sensitization in a cohort of 170 children with asthma, ages
6-11 yr, living in central California. Sensitization to at least one allergen was associated with higher
levels of PMio and CO during the entire pregnancy and 2nd trimester and higher PMi0 during the
first 2 yr of life. Sensitization to at least one indoor allergen was associated with higher exposures to
PMio and CO in during the entire pregnancy and during the 2nd trimester. However, no significant
associations remained for PMio after adjustment for copollutants, effect modifiers,  or potential
cofounders in addition to year of birth. The authors advise that the large number of comparisons may
be of concern and this study should be viewed as an exploratory, hypothesis-generating undertaking.
In examining the National Health Interview Survey for the years  1997-2006, Bhattacharyya et al.
(2009, 180154) found relationships between air quality and the prevalence of hay fever and sinusitis.
However, the air quality data were not clearly defined and as such caution is required in
interpretation of these results. In contrast, Bayer-Oglesby et al. (2005,  086245) found no significant
association between declining levels of PMio and hay fever in Switzerland. In a study by Oftedal et
al. (2007, 191948) conducted in Oslo, Norway, early-life exposure to PMio or PM2.5 was generally
not associated with sensitization to allergens in 9- to 10-yr-old children; lifetime exposures to PMio
and PM2.5 were associated with dust mite allergy, but the association was diminished by adjustment
for socioeconomic factors . In Norway, wood burning in the wintertime is thought to account for
about half of the PM2.5 levels. Although associations between PM and  reactivity to specific allergens
have been reported in long-term studies, there is a consistent lack of correlation between PM and
total IgE levels, indicating a selective enhancement of allergic responses.


7.3.6.2.   lexicological Studies


      Diesel Exhaust

      Exposure to relatively low doses of DE has been shown to exacerbate asthmatic responses in
ovalbumin (OVA) sensitized and challenged BALB/c mice (Matsumoto et al., 2006, 098017). Mice
were intraperitoneally sensitized and intranasally challenged 1 day prior to inhalation exposure to
DE (PM concentration  100 ug/m3; CO, 3.5 ppm; NO2, 2.2 ppm; SO2 O.01 ppm) for 1 day or 1, 4, or
8 wk (7/h/day, 5 days/wk, endpoints 12 h post DE exposure). Results from the 1- and 4-wk
exposures are described in Section 6.3.6.3. It should be noted that control mice were left in a clean
room as opposed to undergoing chamber exposure to filtered air. The significant increases in AHR
and airway sensitivity observed following snorter exposure periods did not persist at 8 wk. BALF
cytokines were altered by DE exposure with only RANTES significantly elevated after 8 wk. DE
had no effect on OVA challenge-induced peribronchial inflammatory or mucin positive cells. These
results suggest that adaptive processes may have occurred during prolonged exposure to DE.


      Gasoline Exhaust

      In a study by Reed et al. (2008, 156903). BALB/c mice were exposed to  whole gasoline
exhaust diluted 1:10 (H), 1:15 (M), or 1:90 (L), filtered exhaust at the  1:10 (HF), or clean air for
6 h/day (atmospheric characterization described in Section 6.3.6.3). GEE exposure from conception
through 4 wk of age induced slight but non-significant increases in OVA-specific IgGl in offspring
but had no significant effect on airway reactivity, BALF cytokine or cell concentrations, although
there were non-significant increases in lung neutrophils and eosinophils. Significant increases in
total serum IgE were observed, but this effect persisted after filtration of particles and was thus
attributed to gas phase components.
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      Woodsmoke

      In a study by Tesfaigzi et al. (2005, 156116). Brown Norway rats were sensitized and
challenged with OVA. Rats were exposed for 70 days to filtered air or to 1,000 (ig/m3 hardwood
smoke. Particles were characterized by aMMAD of 0.36 (im. Concentrations of gases were reported
to be 13.0 ppm CO and 3.1 ppm total vapor hydrocarbon with negligible NOX. Respiratory function
was measured in anesthetized animals by whole-body plethysmography and demonstrated a
significant increase in functional residual capacity as well as a significant increase in dynamic lung
compliance in hardwood smoke-exposed animals compared to controls. No change in total
pulmonary resistance or airway responsiveness to methacholine was observed. BALF inflammatory
cells were not increased, although histological analysis  demonstrated focal inflammation including
granulomatous lesion and eosinophilic infiltrations in hardwood smoke-exposed rats. Alterations of
several cytokines in BALF and plasma were noted. Changes in airway epithelial mucus cells and
intraepithelial stored mucosubstances were modest and  did not  achieve statistical significance.
Results of this study demonstrate that subchronic exposure to hardwood smoke had minimal effects
on pulmonary responses in a rat model of allergen sensitization and challenge.


7.3.7.  Host Defense



7.3.7.1.   Epidemiologic Studies

      Epidemiologic studies of respiratory infections indicate an association with PM. This is more
evident when considering short-term exposures (Chapter 6), but studies of long-term exposures have
observed associations with general respiratory symptoms often caused by infection, such as
bronchitis. In a birth cohort study of approximately 4,000 Dutch children, Brauer et al. (2007,
09069Prescribed in Section 7.3.1.1) found significant positive associations for PM2.5 with
ear/nose/throat infections and doctor-diagnosed flu/serious cold in the first 4 yr of life. These results
are consistent with an earlier study by Brauer et al. (2006, 090757). which found that an increase of
10 (ig/m3 PM25 was associated with increased risk for ear infections in the Netherlands [OR 1.50
(95% CI, 1.00-2.22)]. A Swiss study by Bayer-Oglesby  et al. (2005, 086245). discussed in
Section 7.3.1.1 above, demonstrated that declining levels of PMi0 were associated with declining
prevalence of common cold and conjunctivitis. Because traffic-related pollutants such  as UFPs are
high near major roadways and then decay exponentially over a  short distance, Williams, et al. (2009,
191945) assessed exposure according to residential proximity to major roads in a Seattle area study
of postmenopausal women. Proximity to major roads was associated with a 21% decrease in natural
killer cell function, which is an important defense against viral  infection and tumors. This finding
was limited to women who reported exercising near traffic; other markers of inflammation and
lymphocyte proliferation did not consistently differ according to proximity to major roads. In the
Puget Sound region of Washington, Karr et al. (2009, 191946) reported that there may  be a modest
increased risk of bronchiolitis related to PM2.5 exposure for infants born just before the peak
respiratory syncytial virus (RSV) season. Risk estimates were stronger when restricted to cases
specifically attributed to RSV and for infants residing closer to  highways. Emerging evidence
suggests that respiratory infections, particularly infection by viruses such as RSV, can cause asthma
or trigger asthma attacks.


7.3.7.2.   lexicological Studies



      Diesel Exhaust

      DE may affect  systemic immunity. The proliferative response of A/J mouse spleen cells
following stimulation with T cell mitogens was suppressed by 6 mo of daily exposure to  DE at
concentrations at or above 300 (ig/m3 PM (Burchiel et al., 2004, 055557). B cell proliferation was
increased at 300 (ig/m3 but unaffected at higher concentrations  (up to 1,000 (ig/m ). Concentrations
of gases and were reported in the parallel study by Reed et al. (2004, 055625). described in
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Section 7.3.3.2. The Reed study reported a decrease in spleen weight in male mice (27% reduction in
the 300 (ig/m3 exposure group). The immunosuppressive effects of DE were not due to PAHs or
benzo(a)pyrene (BaP)-quinones (BPQs) since there were little, if any, of these compounds present in
the chamber atmosphere. It should be noted that sentinel animals were negative for mouse
parvovirus at the start of the study, but seroconverted by the end of the study, indicating possible
infection. Parvovirus can interfere with the modulation of lymphocyte mitogenic responses (Baker,
1998, 156245). A 6-month exposure (6h/day, 7d/wk) to 30, 100,  300 or 1,000 (ig/m3 of PM in DE did
not significantly affect bacterial clearance in C57BL/6 mice infected withPseudomonas aeruginosa,
although all levels reduced bacterial clearance when the exposure only lasted a week (Harrod et al.,
2005, 088144). Characterization of the exposure atmosphere was given by Reed et al. (2004,
055625) (Section 7.3.3.2.).


      Gasoline Exhaust

      In a study by Reed et al. (2008, 156903) (described in Section 6.3.7.2) long-term exposure to
fresh gasoline exhaust (6h/day, 7d/wk for 6 mo) did not affect clearance of P. aeruginosa from the
lungs of C57BL/6 mice.


      Hardwood Smoke

      One study demonstrated immunosuppressive effects of hardwood smoke (Burchiel et al., 2005,
088090). Exposure to hardwood smoke increased proliferation of T cells from A/J mice exposed
daily to 100 (ig/m3 PM for 6 mo, but produced a concentration-dependent suppression of
proliferation at PM concentrations >300 (ig/m3. No effects on B  cell proliferation were observed.
Concentrations of NO and NO2 were not detectable or <40 ppb for all exposure levels. CO was
reported to be 2, 4, and 13 ppm for the 100, 300 and 1,000 (ig/m3 PM concentrations, respectively.
Exposure atmospheres contained significant levels  of naphthalene and methylated napthalenes,
fluorene, phenanthrene, and anthracene, as well as  low concentrations of several metals (K, Ca, and
Fe) (Burchiel et al., 2005, 088090). It should be noted that serologic analysis of study sentinel
animals indicated infection with parvovirus , which can interfere with the modulation of lymphocyte
mitogenic responses (Baker, 1998, 156245). In another study by Reed et al. (2006, 156043)
C57BL/6 mice were exposed to 30-1,000 (ig/m3 hardwood smoke by whole-body inhalation for 6
mo prior to instillation of P. aeruginosa. Exposure  characterizations are described in Section 7.3.3.2.
Although there was a trend toward increased clearance with increasing exposure  concentrations,
there was no statistically significant effect of hardwood smoke exposure on bacterial clearance.


7.3.8.  Respiratory Mortality

      Two large U.S. cohort studies examined the effect of long-term exposure to PM2.5 on
respiratory mortality  with mixed results. In the ACS study, Pope et al. (2004, 055880) reported
positive associations  with deaths from specific cardiovascular diseases, but no PM2.5 associations
were found with respiratory mortality. A follow-up to the Harvard Six Cities study (Laden et al.,
2006, 087605) used updated air pollution and mortality data and found positive associations between
long-term exposure to PM2.5 and mortality. Of special note is a statistically significant reduction in
mortality risk reported with reduced long-term fine particle concentrations observed for deaths due
to cardiovascular and respiratory causes,  but not for lung cancer deaths. There is  some evidence for
an association between PM25 and respiratory mortality among post-neonatal infants (ages 1 month-1
year) (Section 7.4.1). In summary, when deaths due to respiratory causes are separated from all-
cause (nonaccidental) and cardiopulmonary deaths, there is limited and inconsistent evidence for an
effect of PM25 on respiratory mortality, with one large cohort study finding a reduction in deaths due
to respiratory causes  associated with reduced PM2 5 concentrations, and another large cohort study
finding no PM2 5 associations with respiratory mortality.
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7.3.9.  Summary and Causal  Determinations



7.3.9.1.   PM2.5

      The epidemiologic studies reviewed in the 2004 PM AQCD suggested relationships between
long-term PMi0 and PM2.5 (or PM2.i) exposures and increased incidence of respiratory symptoms and
disease. One of these studies indicated associations with bronchitis in the 24-city cohort (Dockery et
al., 1996, 046219). They also suggested relationships between long-term exposure to PM2.5  and
pulmonary function decrements in the CHS (Gauderman et al., 2000, 012531; Gauderman et al.,
2002, 026013). These findings added to the database of the earlier 22-city study of PM2.i (Raizenne
et al., 1996, 077268) that found an association between  exposure to ambient particle strong  acidity
and impairment of lung function in children. No long-term exposure toxicological studies were
reported in the 2004 PM AQCD.
      Recent studies have greatly expanded the evidence available since the 2004 PM AQCD. New
analyses have been conducted that include longer follow-up periods of the CHS cohort through 18 yr
of age and provide evidence that effects from  exposure to  PM2 5 persist into early adulthood.
Gauderman et al. (2004, 056569) reported that PM2 5 exposure was associated with clinically and
statistically significant deficits in FEVi attained at the age of 18 yr. In addition, the strength and
robustness of the outcomes were larger in magnitude, and more precise than previous CHS studies
with shorter follow-up periods. Supporting this result are new longitudinal cohort studies conducted
by other researchers in other locations with different methods. These studies report results for PMi0
that is dominated by PM2 5. New studies provide positive associations from Mexico City, Sweden,
and a national cystic fibrosis cohort in the U.S. A natural experiment in Switzerland, where  PM
levels had decreased, reported that improvement in air quality may slow the annual rate of decline in
lung function in adulthood, indicating positive consequences for public health. Thus, the data are
consistent and coherent across several study designs, locations and researchers. As was found in the
2004 PM AQCD, the studies report associations with PM2 5 and PMi0, while most did not evaluate
PMio_2.5. Associations have been reported with fine particle components, particularly EC and OC.
Source apportionment methods generally have not been used in these long-term exposure studies.
      Coherence and biological plausibility for the observed associations with lung function
decrements is provided by toxicological studies (Section7.3.2.2). A recent study demonstrated that
pre- and postnatal exposure to ambient levels  of urban particles affected mouse lung development, as
measured by anatomical and functional indices (Mauad  et al., 2008, 156743). Another study
suggested that the developing lung may be susceptible to PM since acute exposure to UF iron-soot
decreased cell proliferation in the proximal alveolar region of neonatal rats (Pinkerton et al., 2004,
087465) (Section 6.3.5.3). Impaired lung development is a viable mechanism by which PM may
reduce lung function growth in children. Other animal toxicological studies have demonstrated
alterations in pulmonary function following exposure to DE and wood smoke (Section 7.3.2.2).
      An expanded body of epidemiologic evidence for the effect of PM2 5 on respiratory symptoms
and asthma incidence now includes prospective cohort studies conducted by different researchers in
different locations, both within and outside the U.S. with different methods. The CHS provides
evidence in a prospective longitudinal cohort study that relates PM2 5 and bronchitic symptoms and
reports larger associations for within-community effects that are less subject to confounding than
between-community effects (McConnell et al., 2003, 049490). Several new studies report similar
findings with long-term exposure to PMi0 in areas where fine particles predominate. In England, an
association was seen with an increased prevalence of cough without a cold. Further evidence
includes a reduction of respiratory symptoms corresponding to decreasing PM levels in natural
experiments in cohorts of Swiss school children (Bayer-Oglesby et al., 2005, 086245) and adults
(Schindler et al., 2009,  191950).
      New studies examined the relationship between long-term PM2 5 exposure and asthma
incidence. PM2 5 had the strongest modifying effect on the association between lung function with
asthma in an analysis of the CHS (Islam et al., 2007, 090697). The loss of protection by high lung
function against new onset asthma in high PM2 5 communities was  observed for all the lung function
measures. In the Netherlands, an association with doctor-diagnosed asthma was found in a birth
cohort examining the first 4 yr of life (Brauer  et al., 2007, 090691) Further, findings from an adult
cohort suggest that traffic-related PMi0 contributes to asthma development and that reductions  in PM
decrease asthma risk (Kunzli et al., 2009, 191949).
December 2009                                 7-42

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      A large proportion of asthma is driven by allergy, and the majority of recent epidemiologic
studies examining allergic (or atopic) indicators found positive associations with PM2 5 or PMi0
(Section 7.3.6.1). Limited evidence for PM-mediated allergic responses is provided by toxicological
studies of DE and woodsmoke, while effects of gasoline exhaust were attributed to gaseous
components (Section 7.3.6.2).
      Long-term PM2.5 exposure is associated with pulmonary inflammation and oxidative
responses. An epidemiologic study found a relationship between PM2.5 and increased inflammatory
marker eNO among school children (Dales et al., 2008, 156378). Toxicological studies of pulmonary
inflammation have demonstrated mixed results, with subchronic DE exposures generating increases
and CAPs and wood smoke inducing little or no response (Section 7.3.3.2). The pulmonary
inflammation observed with DE was attributable to the particle fraction. Toxicological studies also
reported evidence of oxidative responses (Section 7.3.4.1). Adaptation to prolonged DE was
observed for some oxidative responses in addition to some allergic and pulmonary function
responses (Section 7.3.2.2 and 7.3.6.2).
      Additional support for the relationship between long-term PM2.5 exposures and respiratory
outcomes is provided by pulmonary injury responses observed in toxicological studies (Section
7.3.5.1). Markers of pulmonary injury were increased in rats exposed to DE and gasoline exhaust;
and these changes were attributable to PM. Further, lung DNA methylation was observed in the
gasoline exhaust study. Histopathological changes have also been reported following exposure to
heavily-trafficked urban air and woodsmoke. Findings include nasal and airway mucous cell
hyperplasia accompanied by alterations in mucus production which can lead to a loss of mucus-
mediated protective functions; exacerbation of protease-induced emphysema; and mast cell
infiltration and hypertrophy of alveolar walls. These results provide biological plausibility for
adverse respiratory outcomes following long-term PM exposure.
      Limited information is available on host defense responses (Section 7.3.7) and respiratory
mortality (Section 7.3.8) resulting from PM2.5 exposure.  Several recent epidemiologic studies
suggest a relationship between long-term exposure to PM25 or PMi0 and infection in children and
infants (Section 7.3.7.1). A few toxicological studies  suggest that DE exposure affects systemic
immunity, and although impaired bacterial clearance is associated with short-term exposures to DE,
neither DE or gasoline exhaust seems to have this effect after longer exposures (Section 7.3.7.2).
      In summary, the strongest evidence for a relationship between long-term exposure to PM2 5
and respiratory morbidity is provided by epidemiologic studies demonstrating associations with
decrements in lung function growth in children and with respiratory symptoms and disease incidence
in adults. Mean PM25 concentrations in these study locations ranged from 13.8 to 30 ug/m3 during
the study periods. These studies provide evidence for associations in areas where PM is
predominantly fine particles. A major challenge to interpreting the results of these studies is that the
PM size fractions and concentrations of other air pollutants are often correlated; however, the
consistency of findings across different locations supports an independent effect of PM25. Recent
toxicological studies provide support for the associations with PM2 5 and decreases in lung function
growth in children. Pre- and postnatal exposure to ambient levels of urban particles  was found to
affect mouse lung development, which provides biological plausibility for the epidemiologic
findings. Recent subchronic and chronic toxicological studies also demonstrate altered pulmonary
function, mild inflammation, oxidative responses, histopathological changes including mucus cell
hyperplasia and enhanced allergic responses in response to CAPs, DE, urban air and woodsmoke and
provide further coherence and biological plausibility. Exacerbation of emphysematous lesions was
noted in one study involving exposure to urban air in a heavily-trafficked area. Collectively, the
evidence is sufficient to conclude that the relationship between long-term PM  exposure
and respiratory effects is likely to be causal.


7.3.9.2.   PM10.2.5

      The 2004 PM AQCD did not report long-term exposure studies for PMi0_2.s. The only recent
study to evaluate long-term exposure to PMi0_2.5 found positive, but not  statistically  significant
associations with eNO (Dales et al., 2008, 156378). The evidence is inadequate to determine if 3
causal relationship exists between long-term PMi025 exposures and respiratory effects
December 2009                                  7-43

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7.3.9.3.   UFPs
      The 2004 PM AQCD did not report long-term exposure studies for UFPs. The current
evidence for long-term UFP effects is limited to toxicological studies. Generally, subchronic
exposure to DE induced pulmonary inflammation, which was in contrast to UF CAPs exposure
(Section 7.3.3.2) It appeared that the PM fraction was responsible for the inflammatory response
with DE exposure. Long-term exposure to DE also resulted in oxidative and allergic responses,
although lung injury was not remarkable (Sections 7.3.4.1 and 7.3.6.2). The evidence is inadequate
to determine if a causal relationship exists between long-term UFP exposures and
respiratory effects


7.4.  Reproductive, Developmental, Prenatal and  Neonatal
Outcomes
7.4.1.  Epidemiologic Studies

      This section evaluates and summarizes the scientific evidence on PM and developmental and
pregnancy outcomes and infant mortality. Infants and fetal development processes may be
particularly vulnerable to PM exposure, and although the physical mechanisms are not fully
understood, several hypotheses have been proposed involving direct effects on fetal health, altered
placenta function, or indirect effects on the mother's health (Bracken et al., 2003, 156288; Clifton et
al., 2001, 156360: Maisonet et al., 2004, 156725: Schatz et al., 1990, 156073: Sram et al., 2005,
087442). Study of these outcomes can be difficult given the need for detailed data and potential
residential movement of mothers during pregnancy. Two recent articles have reviewed
methodological issues relating to the study  of outdoor air pollution and adverse birth outcomes (Ritz
and Wilhelm, 2008, 156914: Slama et al., 2008, 156985).  Some of the  key challenges to
interpretation of these study results include the difficulty in assessing exposure as most studies use
existing monitoring networks to estimate individual exposure to ambient PM; the inability to control
for potential confounders such as other risk factors that affect birth outcomes (e.g., smoking);
evaluating the exposure window (e.g., trimester) of importance; and limited evidence on the
physiological mechanism of these effects (Ritz  and Wilhelm, 2008,  156914; Slama et al., 2008,
156985). Another uncertainty is whether PM effects differ by the child's sex. A review of preterm
birth and low birth weight studies found limited indication that effects  may differ by gender,
however sample size was limited (Ghosh et al., 2007, 091233).
      Previous summaries of the association between PM concentrations and pregnancy outcomes
and infant mortality were presented in previous  PM AQCDs. The 1996 PM AQCD concluded that
although few studies had been conducted on the link between PM and infant mortality, the research
"suggested an association," particularly for post-neonates  (U.S. EPA, 1996, 079380).  In the 2004 PM
AQCD, additional evidence was available on PM's effect  on fetal and early postnatal development
and mortality (U.S. EPA, 2004, 056905) and although some studies indicated a relationship between
PM and pregnancy outcomes, others did not. Studies identifying associations found that exposure to
PMio early during pregnancy (first month of pregnancy) or late in the pregnancy (6 wk prior to birth)
were linked with higher risk of preterm birth, including models adjusted for other pollutants, and that
PM2.5 during the first month of pregnancy was associated with  intrauterine growth restriction.
However, other work did not identify relationships between PMio exposure and low birth weight.
The state of the science at that time, as indicated in the 2004 PM AQCD, was that the research
provided mixed results based  on studies from multiple countries, and that additional research was
required to better understand the impact of PM on pregnancy outcomes and infant mortality.
Considering evidence from recent studies discussed below, along with  previous AQCD conclusions,
epidemiologic studies consistently report associations between PMio and PM2.5 exposure and low
birth weight and infant mortality, especially during the post-neonatal period. Animal toxicological
evidence supports these associations with PM2 5, but provides little mechanistic information or
biological plausibility. Information on the ambient concentrations of PMio and PM2.5 in these study
locations can be found in Table 7-5.
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7.4.1.1.   Low Birth Weight

      A large number of studies have investigated exposure to ambient PM and low birth weight at
term, including a U.S. national study, as well as two studies in the northeast U.S., and four in
California. Parker and Woodruff (2008, 156846) linked U.S. birth records for singletons delivered at
40-wk gestation in 2001-2003 during the months of March, June, September and December to
quarterly estimates of PM exposure by county of residence and month of birth. They found an
association between PMi0_2.5 and birthweight (-13 g [95% CI: -18.3 to -7.6]) per 10 ug/m3 increase),
but no such association for PM2 5.
      Maisonet et al. (2001, 016624) analyzed 89,557 births (1994-96) in six northeastern cities
(Boston and Springfield MA; Hartford CT; Philadelphia and Pittsburgh PA; and Washington DC).
Each city had three PMi0 monitors measuring every sixth day. Results  from multiple monitors were
averaged in each city. Exposure was determined for each trimester of pregnancy and categorized by
quartiles (<25, 25-30, 31-35, 36-43 ug/m3) and 95th percentile (>43ug/m ). There was no increased
risk for low birth weight at term associated with PMi0 exposure during any trimester of pregnancy.
When birth weight was considered as a continuous outcome, exposure to PMi0 was not associated
with a reduction in mean  birth weight.
      In contrast, Bell et  al. (2007, 093256) reported positive associations for both PM2.5 and  PMi0
with birth weight in a study of births (n = 358,504) in Connecticut and Massachusetts (1999-2002).
Birth data indicated county, not street address or ZIP code, so women were assigned exposure based
on county residence at delivery. The difference in birth weight per 10 ug/m3 associated with PM25
was -66.8 (95% CI: -77.7 to -55.9) g. For PM10 it was -11.1 (95% CI: -15.0 to -7.2) g. The increased
risk for low birth weight was OR = 1.054 (95% CI: 1.022-1.087) for PM2.5 and OR = 1.027 (95% CI:
0.991-1.064) for PMi0, based on average exposure during pregnancy. Reductions in birth weight
were also  associated with third trimester exposure to  PMi0 and second and third trimester exposure
to PM25. Comparing this  study to Maisonet et al. (2001, 016624). a larger sample size was able to
detect a small increase in risk. In addition, birth weight was reduced more by exposure to PM2 5 than
by exposure to PMi0. Measured PM2 5 concentrations were not available in the earlier study.
      The Children's Health Study is a population based cohort of children living in  12 southern
California communities, selected on the basis of differing levels of air  pollution (Salam et al.,  2005,
087885). as previously discussed in Section 7.3.  The children in grades 4, 7 and 10 were recruited
through schools. A subset of this cohort (n = 6,259) were born in California from 1975-1987.  Of
these, birth certificates were located for 4,842, including 3,901 infants born at term and 72 cases of
low birth weight at term.  Using the mother's ZIP code at the time of birth, exposure was determined
by inverse distance weighting of up to three PMi0 monitors within 50 km of the ZIP code centroid. If
there was  a PMi0 monitor within 5 km of the ZIP code centroid (40% of data), exposure from  that
monitor was used. Exposure was calculated for the entire pregnancy, and for each trimester of
pregnancy. A 10 ug/m increase in PMi0 during the third trimester reduced mean birth weight  -10.9 g
(95% CI: -21.1 to -0.6) in single pollutant models, but became non-significant in copollutant models
controlling for the effects of O3. Increased risks of low birth weight (<2,500 g) were not statistically
significant (OR =1.3 [95% CI: 0.9-1.9]). A strength of this study was the cohort data available
included information on SES and smoking during pregnancy. A limitation is the assignment of
exposure based on monitoring stations up to 50 km distant; this may have introduced substantial
exposure misclassification obscuring some associations.
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Table 7-5. Characterization of ambient PM concentrations from studies of reproductive,
developmental, prenatal and neonatal outcomes and long-term exposure.
Study
Location
Mean Annual
Concentration (ug/m3)
Upper Percentile
Concentrations (ug/m3)
PM2.5
Basu et al. (2004, 0878961
Bell et al. (2007, 0910591
Braueretal. (2008, 156292)
Huynh et al. (2006, 0912401
Jalaludin et al. (2007, 1566011
Liu (2007, 0904291
Loomisetal. (1999, 087288)
Mannes et al. (2005, 087895)
Parker et al. (2005, 0874621
Ritz et al. (2007, 0961461
Wilhelm and Ritz (2005, 0886681
Woodruff etal. (2006, 088758)
Woodruff etal. (2008, 0983861
CA
CIS MA
Vancouver, Canada
CA
Sydney, Australia
Multicity, Canada
Mexico City
Sydney, Australia
CA
Los Angeles, CA
Los Angeles, CA
CA
U.S.
Range of means across sites: 14.5-18.2
Avg of means across sites: 16.2
22.3
5.3
Range of means across trimesters: 17.5-18.8
Avg of means across trimesters: 18.2
9.0
12.2
27.4
9.4
15.4
20.0
21.0
19.2a
Range of means across effects: 1 4.5-1 4.9a
Avg of means across effects: 14.8a
Max: 26.3-34.1

Max: 37.0


75th: 15
Max: 85
75th: 11.2; Max:


Max: 38.9-48.5
75th: 22.7
75th: 18.5-18.7







82.1





PMiO-2.5
Parker et al. (2008, 156013)
U.S.
13.2
75th: 17.5

PM10
Bell et al. (2007, 093256)
Braueretal. (2008, 156292)
Chen et al. (2002, 024945)'
Gilboa et al. (2005, 0878921
Ha et al. (2003, 0425521
Hansen et al. (2006, 089818)
Hansen et al. (2007, 090703)
Jalaludin et al. (2007, 156601)
Kim et al. (2007, 1566421
Lee et al. (2003, 043202)
Leem et al. (2006, 089828)
Lipfert et al. (2000, 004103)
Maisonet etal. (2001,016624)
Mannes et al. (2005, 0878951
Pereiraetal. (1998, 007264)
Ritz et al. (2000, 012068)
Ritz et al. (2006, 0898191
CIS MA
Vancouver, Canada
Wfeshoe County, NV
TX
Seoul, South Korea
Brisbane, Australia
Brisbane, Australia
Sydney, Australia
Seoul, Korea
Seoul, Korea
Incheon, Korea
U.S.
NEU.S.
Sydney, Australia
Sao Paulo, Brazil
CA
CA
22.3
12.7
31.53
23.8a
69.2
19.6
19.6
16.3
Range of means across time: 88.7-89.7
Avg of means across time: 89.2
71.1
53.8a
33.1
31. Oa
16.8
65.04
49.3
46.3

Max: 35.4


75th: 39.35; Max: 157.32
75th: 29
75th: 87.7; Max:
Max: 171.7
75th: 22.7; Max:


75th: 89.3; Max:
75th: 64.6; Max:
Max: 59
75th: 36.1; Max:
75th: 19.9; Max:
Max: 192.8
Max: 178.8
Max: 83.5

245.4

171.7


236.9
106.39

46.5
104.0



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Study
Rogers and Dunlop (2006, 0912321
Romieu et al. (2004, 093074)
Sagiv et al. (2005, 0874681
Salam et al. (2005, 0878851
Suh et al. (2008, 1920771
Tsai et al. (2006, 090709)
Wilhelm and Ritz (2005, 0886681
Woodruff etal. (2008, 0983861
Yang et al. (2006, 090760)
Location
GA
Ciudad Juarez, Mexico
PA
CA
Seoul, Korea
Kaohsiung, Taiwan
Los Angeles, CA
U.S.
Taipei, Taiwan
Mean Annual
Concentration (ug/m3)
3.75
33.0-45.9
Range of means across time: 25.3-27. 1
Avg of means across time: 26.2
Range of means across trimesters: 45.4-46.6
Avg of means across trimesters: 45.8
Range of means across trimesters: 54.6-61 . 1
Avg of means across trimesters: 58.27
81.5
38.1
Range of means across effects: 28.6-29.8a
Avg of means across effects: 29. f
53.2
Upper Percentile
Concentrations (ug/m3)
75th: 15.07

Max: 68.9-156.3

75th: 62.8-67.8
Max: 85.1-107.36
75th: 111. 5; Max: 232.0
Max: 74.6-103.7
75th: 33.8-36.5
75th: 64.9; Max: 234.9
3Median concentration
      Parker et al. (2005, 087462) examined births in California within 5 miles of a monitoring
station (n = 18,247). Only infants born at 40 wk gestation were included. Thus all infants were the
same gestational age, and had been exposed in the same year. Exposure to PM2.5 in quartiles (<11.9,
11.9-13.9, 14.0-18.4, >18.4) was associated with decrements in birth weight. Infants exposed to
>13.9 ug/m3 experienced reductions in birth weight (third quartile -13.7 g (95% CI: -34.2 to 6.9),
fourth quartile -36.1 g (95% CI: -55.8 to -16.5). These are larger reductions than have been seen in
some other studies. However, this study reduced misclassification by including only women living
within 5 miles of a monitoring station, and only included births at 40 wk gestation. Reducing
misclassification should lead to a stronger association, if the association is causal.
      The effects of spatial variation in exposure were also investigated by Wilhelm and Ritz (2005,
088668). Their study included all women living in ZIP codes where 60% of the ZIP code was within
two miles of a monitoring station in the Southern California Basin, and women with known
addresses in Los Angeles County within 4 miles  of a monitoring station. Exposure to average PMi0
in the third trimester was analyzed for increased risk of low birth weight at term (> 37-wk gestation).
Analysis at the ZIP code level did not detect increased risk (per 10 ug/m3 PM10s OR = 1.03 [95% CI:
0.97-1.09]). However the analysis based on geocoded addresses indicated that increasing exposure to
PMio was associated with increased risk of low birth weight for women living within 1  mile of the
station where PMi0 was measured. For these women  (n = 247 cases, 10,981 non-cases), each
10 ug/m3 increase in PMio was associated with a 22% increase in risk of term low birth weight
(OR = 1.22 [95% CI: 1.05-1.41]). In the categorical analysis, exposure to PM10 >44.4 ug/nrwas
associated with a 48% increase in risk (OR = 1.48 [95% CI:  1.00-2.19]). Increased risk of low birth
weight also was associated with exposure to CO  in single pollutant models. However, when
multipollutant models were considered, the effects of CO were attenuated but the effects of PMio
increased. Controlling for CO, NO2, and O3, each 10 ug/m3 increase in exposure to PMio increased
risk of low birth weight 36% (OR = 1.36 [95% CI: 1.12-1.65]).
      Spatial variation in PM2.5 exposure was investigated by Basu et al. (2004, 087896). They
included only mothers who lived within 5  miles of a  PM2 5 monitor and within a California county
with at least 1  monitor. To minimize potential confounding, they included only white (n = 8,597) or
Hispanic (n = 8,114) women, who were married, between 20 and 30 yr of age, completed at least
high school and were having their first child. Consistently, PM2 5  exposure measured by the county
monitor was more strongly associated with reductions in birth weight than exposure measured by the
neighborhood monitor. The results were replicated in both the white and the Hispanic samples.
Reductions in birth weight ranged from 15.2 to 43.5 g per 10 ug/m3 increase in PM25.
      In the remaining U.S. study, Chen et al. (2002, 024945) analyzed 33,859 birth certificates of
residents of Washoe County in northern Nevada (1991-1999). There were four sites monitoring
during the study period, it appears  (not stated) that exposure was  averaged over the county. A
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10 ug/m3 increase in exposure to PM10 during the third trimester of pregnancy was associated with
an 11 g reduction in birth weight (95% CI: -2.3 to -19.8). Effects on risk of low birth weight were not
statistically significant. For exposure in the third trimester of 19.77 to 44.74 ug/m3 compared to
<19.74 ug/m3 the odds ratio for low birth weight was 1.05 (95% CI: 0.81-1.36). Comparing exposure
>44.74 to the same reference category, the odds ratio was 1.10 (95% CI: 0.71-1.71).
Misclassification of exposure may have occurred when exposure was averaged over a large
geographic area (16,968 km2).
     Recent international studies  investigating effects of particles on low birth weight include one
in Munich (Slama et al, 2007, 093216). two in Canada (Brauer et al, 2008, 156292; Dugandzic et
al., 2006, 088681). two in Australia (Hansen et al., 2007, 090703: Mannes et al., 2005, 087895). two
in Taiwan (Lin et al., 2004, 089827: Yang et al., 2003, 087886) one in Korea (Ha et al., 2003,
042552) and two in Sao Paulo, Brazil (Gouveia et al., 2004, 055613: Medeiros and Gouveia, 2005,
089824). The majority of these studies found that PM concentrations were associated with low birth
weight, though two studies (Hansen et al., 2007, 090703: Lin et al., 2004, 089827) found no
associations. The effect estimates were similar in magnitude to those reported in the U.S. studies.


     Considerations in Interpreting Results of Low Birth Weight Studies

     Studies included subjects at  distances from monitoring stations varying from as close as 1 mile
or 2 km, to as far as 50 km or the size of the county. Studies that only included subjects living within
a short distance (1 mile, 2 km) of the monitoring station (thus likely reducing exposure measurement
error) were more likely to find that PM exposure was associated with increased risk of low birth
weight. However, Basu et al. (2004, 087896) reported a stronger association between PM2.5 exposure
and birth weight when exposure was estimated based on the county monitor, rather than the monitor
within  5 miles of the residence. They suggest that county level exposure may be more representative
of where women spend their time, including not only home, but also other time spent away from
home. Other pollutants also appeared to influence the risk associated with particle exposure. In one
study, exposure to PMi0 in a single pollutant model reduced birth weight by 11 g, but became non-
significant in copollutant models with O3 (Salam et al., 2005, 087885). In another study the risk
associated with PM10 exposure increased from 22% to 36% when other pollutants were included in
the model (Wilhelm and Ritz, 2005, 088668). All but one study in the U.S. found some association
between particle exposure  and reduced birth weight (Maisonet et al., 2001, 016624). The results of
international studies were inconsistent. This might be related to the chemical composition of
particles in the U.S., or to differences in the pollutant mixture. Studies with null results must be
interpreted  with caution when the comparison groups have significant exposure. This was certainly
the situation in studies in Taiwan and Korea (Lee et al., 2003, 043202: Lin et al., 2004, 089827: Yang
et al., 2003, 087886). Differences in geographical locations, study  samples and linkage decisions
may contribute to the diverse findings in the literature on the association between PM and
birthweight, even within the U.S. (Parker and Woodruff, 2008, 156846).


7.4.1.2.   Preterm Birth

     A potential association of exposure to airborne particles and preterm birth has been
investigated in numerous epidemiologic studies, including some conducted in the U.S. and others in
foreign countries. Three U.S. studies have been carried out by the same group of investigators in
California.
     A natural experiment occurred when an open-hearth steel mill  in Utah Valley was closed from
August 1986 through September 1987. Parker et al. (2008, 156013) compared birth outcomes for
Utah mothers within and outside of the Utah Valley, before,  during, and  after the mill closure. They
report that mothers who were pregnant around the time of the closure of the mill were less likely to
deliver prematurely than mothers who  were pregnant before or after. The strongest effect estimates
were observed for exposure during the second trimester (14% decrease in risk of preterm birth
during  mill closure). Preterm birth outside of the Utah Valley did not change during the time of the
mill closure.
     In 2000, Ritz et al. (2000,  012068) published the first  study investigating the association of
preterm birth with PM in the U.S. The  study population was women living in the southern California
Basin. There were eight monitoring stations measuring PMi0 every 6th day during the study period.
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Birth certificates (1989-1993) were analyzed for women living in ZIP codes within 2 miles of a
monitoring station. Women with multiple gestations, chronic disease prior to pregnancy and women
who delivered by cesarean section were excluded resulting in a study population of 48,904 women.
The risk of preterm birth increased by 4% (RR = 1.04 [95% CI: 1.02-1.6]) per 10 ug/m3 increase in
PMio averaged in the 6 wk before birth. Exposure to PMi0 in the first month of pregnancy resulted in
a 3% increase in risk (RR = 1.03 [95% CI: 1.01-1.05]). These results were robust in multipollutant
models.
      Wilhelm and Ritz (2005, 088668) reinvestigated this association among women in the same
area in 2005, when air pollution had declined from a mean level near 50 ug/m3 to a mean level near
40 ug/m3. Birth certificate data from 1994-2000 was analyzed for women living in ZIP codes within
2 miles of a monitoring station, or with addresses within 5 miles of a monitoring station. No
significant effects of exposure to PMi0 were reported. Exposure to PM2.5 6 wk before birth resulted
in an increase in preterm birth (RR = 1.19 [95% CI: 1.02-1.40]) for the highest quartile of exposure
(PM25 >24.3  ug/m3). Using a continuous measure of PM25, there was a 10% increase in risk for each
10 ug/m3 increase in PM2.5 (RR = 1.10 [95% CI: 1.00-1.21]).
      There have been two major criticisms of air pollution studies using birth certificate data. First,
that birth certificates only indicate the address at birth and the exposure of women who moved
during pregnancy may be misclassified; second, that information about some important confounders
may not be available (e.g., smoking). To obtain more precise information about these variables, Ritz
et al. (2007, 096146) conducted a case-control study nested within a cohort of birth certificates (Jan
2003-Dec 2003) in Los Angeles County. Births to women residing in ZIP codes (n = 24) close to
monitoring stations or major population centers or roadways (n = 87) were eligible (n = 58,316
births). All  cases of low birth weight or preterm birth and an equal number of randomly sampled
controls in the 24 ZIP codes close to monitors were selected. In the other 87 ZIP codes, 30% of cases
and an equal number of controls were randomly sampled. Of 6,374 women selected for the case
control study, 2,543 (40%) were interviewed. The association of preterm birth with exposure to
PM2 5 differed between women responding to the survey and women who did not respond. Among
responders, exposure to each 10 ug/m3 increase in PM25 concentration in the first trimester increased
risk to preterm birth by 23%  (RR = 1.23 [95% CI: 1.02-1.48]). There was no increase in risk among
non-responders (RR = 0.95 [95% CI: 0.82-1.10]), or in the entire birth cohort (RR = 1.00 [95% CI:
0.94-1.07]).
      An additional case control study of preterm birth and PM2s exposure (Huynh  et al., 2006,
091240) used California birth certificate data. Singleton preterm infants (24-36-wk gestation) born in
California (1999-2000) whose mothers lived within 5 miles of a PM25 monitor were eligible. Each of
these 10,673 preterm infants  were  matched to three term (39- to 44-wk gestation) controls (having a
last menstrual period within 2 wk of the case infant), resulting in a study population of 42,692.
Controlling for maternal race/ethnicity, education, marital status, parity and CO exposure, exposure
to PM2.5 >17.7 ug/m3 increased the risk of preterm  birth by 14% (OR =1.14 [95% CI: 1.07-1.23]).
Averaging PM25 exposure over the first month of pregnancy, the last 2 wk before birth, or the entire
pregnancy did not substantially change the risk estimate.
      Two additional studies of preterm birth and exposure to particulate air pollution have been
conducted in the U.S. Each has used a unique methodology. Sagiv et al. (2005, 087468) used time
series to analyze births in four Pennsylvania counties between January 1997 and December 2001. In
this analysis,  exposure to PMi0 is compared to the rate of preterm births each day. Both acute
exposure (on the day of birth) and  longer term exposure (average exposure for the preceding 6 wk)
were considered in the analysis. An advantage of this analysis is that days, rather than individuals are
compared, so confounding by individual risk factors is minimized. For exposure averaged over the
6 wk prior to birth, there was an increase in risk (RR = 1.07 [95% CI: 0.98-1.18]), which persisted
for  acute exposure  with a 2-day lag (RR =1.10 [95% CI: 1.00-1.21]) and 5-day lag (RR = 1.07 95%
CI:  0.98-1.18]).
      Rogers and Dunlop (2006, 091232) examined exposure to particles and risk of delivery of an
infant weighing less than  1,500 g (all of which were preterm) from 24 counties in Georgia. The study
included 69 preterm, small for gestational age (SGA) infants, 59 preterm appropriate for gestational
age (AGA) infants  and 197 term AGA controls. Exposure was estimated using an environmental
transport model that considered PMi0 emissions from 32 geographically located industrial point
sources, meteorological factors, and geographic location of the birth home. Exposure was
categorized by quartiles. Comparing women who delivered a preterm AGA infant to those who
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delivered a term AGA infant, exposure to PM10>15.07 ug/m3 tripled the risk (OR = 3.68 [95% CI:
1.44-9.44]).
      Brauer et al. (2008, 156292) evaluated the impacts of PM25 on preterm birth using
spatiotemporal exposure metrics in Vancouver, Canada. The authors found similar results when they
used a land-use regression model or inverse distance weighting as the exposure metric. For preterm
births <37 wk, they reported an OR of 1.06 (95% CI: 1.01-1.11), and for preterm births <35 wk the
OR increased to 1.12 (95% CI: 1.02-1.24). There were no consistent trends for early or late
gestational period to be more strongly associated with preterm births.
      Suh et al. (2008, 192077) conducted a study to determine if the effects of exposure to PMi0
during pregnancy on preterm delivery are modified by maternal  polymorphisms in metabolic genes.
They analyzed the effects of the gene-environment interaction between the GSTM1, GSTT1,
CYPlal-T6235C and -1462V polymorphisms and exposure to PMi0 during pregnancy on preterm
birth in a case-control study in Seoul, Korea. PM10 concentration >  75th percentile alone was
significant in the third trimester of pregnancy (OR = 2.33 [95% CI:  1.33-4.80]), but not in the first or
second trimester. The risk of preterm delivery conferred by the GSTM1 null genotype was increased,
and the highest risk was found during the third trimester of pregnancy (OR = 2.58 [95% CI:
1.34-4.97]). There were no statistical associations with the GSTT1 or CYP1A1  genotypes. When the
gene-environment interaction was analyzed, the risk for preterm birth was substantially higher for
women who carried the GSTM1 null genotype and were exposed to high levels of PMi0 (> 75th
percentile) than for those who carried the GSTM1 positive genotype but were only exposed to low
levels of PMio (<75th percentile) during the third trimester of pregnancy (OR = 6.22, 95% CI:
2.14-18.08).
      In Incheon, Korea, Leem et al. (2006, 089828) estimated PMi0 exposure spatially as well as
temporally. Exposure was based on 26  monitors  and kriging was used to determine exposure for 120
dongs (administrative districts, mean area 7.82 km2, median area 1.42 km3).  The sample included
52,113 births, from 2001-2002. PMio was very weakly correlated with other pollutants. Exposure
was compared in quartiles for the first and third trimester of pregnancy. In the first trimester, relative
risks for the second, third and fourth quartiles were RR = 1.14 (95% CI: 0.97-1.34), RR = 1.07 (95%
CI: 0.94-1.37), and RR = 1.24 (95% CI: 1.09-1.41),  respectively. Exposure to PMio in quartile one
(reference group) was 26.9-45.9 ug/m3; fourth quartile exposure equaled 64.6-106.4 ug/m3. The
p-value for trend was 0.02. Exposure in the third trimester was not related to preterm birth, however
no information was provided to determine how exposure in  the third trimester was adjusted for
women who delivered preterm.
      Two studies investigating risks of preterm birth related to particle exposure have been reported
from Australia. In Brisbane, Hansen et al. (2006, 089818) studied 28,200 births (2000-2003) in an
area of low PMio concentrations.  Exposure to an interquartile range increase in PMio exposure in the
first trimester resulted in a 15% increased risk of preterm birth (OR =1.15 [95% CI: 1.06-1.25]).
This result was strongly influenced by the effect of PMio exposure in the first month of pregnancy
(OR =1.19 [95% CI: 1.13-1.26]). PMi0 was correlated with O3 (r = 0.77) in this study and O3 also
increased risk in the first trimester. No  effects were associated with  exposure to PMio in the third
trimester.
      In Sydney, associations between exposure to particles and preterm birth varied by season.
Jalaludin et al. (2007,  156601) obtained information on all births in metropolitan Sydney
(1998-2000).  Exposure to PM2.5 in the 3 mo preceding birth was associated with an increased risk of
preterm birth (OR = 1.11 [95% CI: 1.04-1.19]). Additional effects were dependent on season of
conception. Both PM10 (OR = 1.3 [95% CI:  1.2-1.5]) and PM2.5 (OR = 1.4 [95% CI: 1.3-1.6]) were
associated with increased risk for conceptions in the winter. Conceptions in summer were associated
with reductions in risk (PM1(? OR = 0.91 [95% CI: 0.88-0.93]) (PM2.5 OR = 0.87 [95% CI:
0.84-0.92]). Due to both positive  and negative findings, the  authors recommend caution in
interpreting their results.


      Considerations in Analyzing  Environmental Exposures and Preterm Birth

      A major issue in studying environmental exposures and preterm birth is selecting the relevant
exposure period, since the biological mechanisms leading to preterm birth and the critical periods of
vulnerability are poorly understood (Bobak, 2000, 011448). Exposures proximate to the birth may be
most relevant if exposure causes an acute effect.  However, exposure occurring in early gestation
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might affect placentation, with results observable later in pregnancy, or cumulative exposure during
pregnancy may be the most important determinant. The studies reviewed have dealt with this issue in
different ways. Many have considered several exposure metrics based on different periods of
exposure.
      Often the time periods used are the first month (or first trimester) of pregnancy and the last
month (or 6 wk) prior to delivery. Using a time interval  prior to delivery introduces an additional
problem since cases and controls are not in the same stage of development when they are  compared.
For example, a preterm infant delivered at 36 wk is a 32-week fetus 4  wk prior to birth, while an
infant born at term (40 wk) is a 36-week fetus 4 wk prior to birth. Only one study (Huynh et al.,
2006, 091240) adjusted for this in the design.
      Many of these studies compare exposure in quartiles, using the lowest quartile as the reference
(or control) group. No studies use a truly unexposed control  group. If exposure in the lowest quartile
confers risk, than it may be difficult to demonstrate additional risk associated with a higher quartile.
Thus negative studies  must be interpreted with caution.
      Preterm birth occurs both naturally (idiopathic preterm), and as  a result of medical
intervention (iatrogenicpreterm). Ritz et al. (2000, 012068;  2007, 096146)  excluded all births by
Cesarean section, to limit their studies to idiopathic preterm. No other studies attempted to
distinguish the type of preterm birth, although PM exposure  maybe associated with only one type.
This is a source of potential effect misclassification.


7.4.1.3.   Growth Restriction

      Low birth weight has often been used as an outcome measure because it is easily available and
accurately recorded on birth certificates. However, low birth weight may result from either short
gestation, or inadequate growth in utero. Most of the studies investigating air pollution exposure and
low birth weight, limited their analysis to term infants to focus on inadequate growth. A number of
studies were identified that specifically  addressed growth restriction in utero by identifying infants
who failed to meet specific growth standards. Usually these infants had birth weights less than the
10th percentile for gestational age, using an external standard. Many of these studies have been
previously discussed, since they also  examined other reproductive outcomes (low birth weight or
preterm delivery).
      Three studies in the U.S. examined intrauterine growth. A recent study (Rich et al., 2009,
180122) investigated very small for gestational age (defined as a fetal  growth ratio <0.75), small for
gestational age (defined as > 75 and <85) and "reference" births (> 85) to women residing in New
Jersey and mean air pollutant concentrations during the  first, second and third trimesters. They
reported an increased risk of SGA associated with first and third trimester PM2 5 concentrations
(1.116 [95% CI: 1.012, 1.232], and 1.106 [1.008-1.212], per 10 ug/m3 PM2.5, respectively). Parker et
al. (2005, 087462) reported a positive association between exposure to PM2.5. Since this study only
included singleton live births at 40-wk gestation,  birth weights less than 2,872 g for girls and 2,986 g
for boys were  designated SGA, based on births in California. Infants exposed to the highest quartile
PM2.5 (>18.4 ug/m ) compared to the lowest quartile PM25 (<11.9 ug/m ) were 23% more likely to
be small for gestational age (OR  = 1.23 [95% CI: 1.03-1.50]).  Very similar results were found for
exposure in each of the three trimesters respectively (OR =1.26 [95% CI: 1.04-1.51], OR =1.24
[95% CI: 1.04-1.49], OR = 1.21 [95% CI: 1.02-1.43]). These results controlled for exposure to CO,
which did not  increase risk for SGA.
      In contrast, Salam et al. (2005,  087885) found no  association between exposure to PMi0 and
intrauterine growth retardation (IUGR) in the California Children's Health Study. IUGR was defined
as less than the 15th percentile of predicted birth weight based on gestational age and sex  in term
infants. Apparently no external standard was used since 15% of infants in the study were designated
as IUGR. An IQR increase in PMi0 exposure was not significantly associated with IUGR for the
whole pregnancy (OR =1.1 [95% CI: 0.9-1.3]) or for any specific trimester. Differences between
this study and the study by Parker et al.  (2005, 087462)  include measurement of PMi0 versus PM25,
a less stringent definition of IUGR, and exposures determined by monitors located much farther
away from the subjects' residences (up to 50 km versus  within 5 mi). All of these factors could lead
to misclassification.
      Two studies investigating particle exposure and SGA were conducted in Australia, with
differing results (Hansen et al., 2007, 090703: Mannes et al., 2005, 087895). Mannes et al. (2005,
087895) defined SGA as birth weight less than two standard deviations below the national mean
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birth weight for gestational age. In this study there was a statistically significant effect of exposure to
both PM10 (OR = 1.10 [95% CI: 1.00-1.48], per 10 ug/m3 increase) and PM2.5 (OR = 1.34 [95% CI:
1.10-1.63], per 10 ug/m3 increase) for exposure during the second trimester. When analysis was
restricted to births within 5 km of the monitoring station, the association for PMi0 became  slightly
stronger (OR = 1.22 [95% CI: 1.10-1.34]). Exposure during other trimesters of pregnancy was not
associated with IUGR.
      In Brisbane, Hansen et al. (2007, 090703) examined head circumference (HC), crown heel
length (CHL) and risk of SGA, defined as less than the tenth percentile of weight for gestational age
and gender based on an Australian national standard. There was no consistent relationship between
PMio exposure and SGA, HC or CHL in any trimester of pregnancy. PMi0 exposure was determined
by averaging values from the five monitoring stations. Due to the sample size and limited number of
monitoring stations, it was not possible to analyze the data for women living within 5 km of a
monitoring station, as was done in Sydney.
      In Canada, Liu et  al. (2007, 090429) investigated the effect of PM2.5 exposure on fetal growth
in three cities, Calgary, Edmonton and Montreal. IUGR was defined as birth weight below the tenth
percentile, by sex and gestational week (37-42) for all singleton live births in Canada between 1986
and 2000. Models were  adjusted for maternal age, parity, infant sex, season of birth, city of
residence, and year of birth. A 10 ug/m3 increase in PM2.5 was  associated with an increased risk for
IUGR (OR = 1.07 [95% CI: 1.03-1.10]) in the first trimester, and similar risks  were associated with
exposure in the second or third trimesters. The effect of PM2.5  was reduced in multipollutant models
including CO and NO2
      Brauer et al. (2008,  156292) observed consistent increased risks  of SGA for PM2.5 PMi0, NO2,
NO and CO in Vancouver, Canada (20% increase in risk in PM25 and PMip per 10 ug/m increase).
The effects were similar for exposure estimates based on nearest monitor, inverse distance
weighting, and land-use regression modeling. ORs for early or late pregnancy  exposure windows
were remarkably similar to those for the full duration of pregnancy.


7.4.1.4.   Birth Defects

      Four recent studies examined  PM and birth defects. The Seoul, Korea study discussed above
also considered congenital anomalies, defined as a defect in the child's body structure (Kim et al.,
2007, 156642). PMi0 levels were associated with higher risk of birth defects for the second trimester,
with a 16% (95% CI: 0-34) increase in risk per 10 ug/m3 in PMi0.
      Two U.S. studies examined air pollution and risk of birth defects. Data were collected from the
California Birth Defects Monitoring Program for four counties in Southern California (Los Angeles,
Riverside, San Bernardino, and Orange) for the  period 1987-1993, although each county included a
subset of this period (Ritz  et al., 2002, 023227). Cases (i.e., infants with birth defects) were
identified as live birth infants and fetal deaths from 20-wk gestation to 1 yr post-birth, with isolated,
multiple, syndrome, or chromosomal cardiac or orofacial cleft defects.  Cases were restricted to those
with registry data for gestational age and residence ZIP code, and those with residences <10 miles
from an air pollution monitor. Six types of categories  were included: aortic defects;  atrium and
atrium septum defects; endocrinal and mitral value defects; pulmonary artery and valve defects;
conotruncal defects; and ventricular septal defects not part of the conotruncal category.  PMi0
measurements were available every  6 days.  While results indicated increased risk of birth defects for
higher levels of CO or O3, the authors determined that results for PMio were inconclusive,  finding no
consistent trend of effect after adjustment for CO and O3.
      The other U.S. study examined birth defects through a case-control design in seven Texas
counties for the period 1997-2000 (Gilboa et al., 2005, 087892). Births were excluded for parents
<18 yr and several non-air pollution risk factors known to be associated with birth defects  (e.g.,
maternal diabetes, holoprosencephaly in addition to oral clef).  Comparison of the highest
(> 29.0  ug/m3) and lowest (<19.521  ug/m3) quartiles of PMio for exposure defined as the third to
eighth week of pregnancy  generated an OR of 2.27 (95% CI: 1.43-3.60) for risk of isolated atrial
septal defects and 1.26 (95% CI: 1.03-1.55) for individual atrial septal defects. Including other
pollutants (CO, NO2, O3, SO2) in the model did not greatly  alter results; numerical results for
copollutant analysis were not provided. Strong evidence was not observed for a relationship between
PMio and the other birth defect categories. Review articles have concluded that the scientific
literature is not sufficient to conclude a relationship between air pollution and birth defects (Sram et
al., 2005, 087442).
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      A recent study of oral clefts conducted in Taiwan found no association between this birth
defect and concentrations of PMi0 during the first or second gestational month (Hwang and
Jaakkola, 2008, 193794). This population-based case-control study included 653 cases and a random
sample of 6,530 controls born in Taiwan between 2001 and 2003.


7.4.1.5.   Infant Mortality

      Many studies have identified strong associations between exposure to particles and increased
risk of mortality in adults or the general population, including for short- and long-term exposure
(Sections 6.5 and 7.6). Less evidence is available for the potential impact on infant mortality,
although studies have been conducted in several countries. The results of these infant mortality
studies are presented here with the other reproductive  and developmental outcomes because it is
likely that in vitro exposures contribute to this outcome. Both long-term and short-term exposure
studies of infant mortality are included in this section. Results on PM and infant mortality includes a
range of findings, with some studies finding associations and many statistically non-significant or
null effects.  Yet, more consistency is observed when results are divided into the type of health
outcome based on the age of infant and cause of death.
      An important question regarding the association between PM and infant mortality is the
critical window of exposure during development for which infants are susceptible. Several age
intervals have been explored: neonatal (<1 mo); infants (<1 yr); and postneonatal (1 mo-1 yr).
Within these various age categories, multiple causes of deaths have been investigated, particularly
total deaths and respiratory-related deaths. The studies reflect a variety of study designs, particle size
ranges, exposure periods, regions, and adjustment for  confounders.


      Stillbirth

      Only one study of stillbirths and PM was identified. A prospective cohort of pregnant women
in Seoul, Korea from 2001 to 2004 was examined with respect to exposure to PMi0 (Kim et al.,
2007, 156642). Gestational age was estimated by the last menstrual period  or by ultrasound.
Whereas many of the previously discussed studies of PM and pregnancy outcomes were based on
national registries, this study examined medical records and gathered individual information through
interviews on socioeconomic condition, medical history, pregnancy complications, smoking, second-
hand smoke exposure, and alcohol use. Mother's exposure to PMi0 was based on residence for each
month of pregnancy, each trimester defined as a three  month period, and the 6 wk prior to death.
Exposure was assigned by the nearest monitor. A  10 (ig/m3 increase in PM10 in the third trimester
was associated with an 8% (95% CI: 2-14) increase in risk of stillbirth.
      In Sao Paulo, Brazil, Poisson regression of stillbirth counts for the period 1991-1992 found
that a 10 (ig/m3 increase in PMi0 was associated with a 0.8% increase in stillbirth rates (Pereira et al.,
1998, 007264). When other pollutants (NO2, SO2, CO, O3) were included simultaneously in the
model, the association did not remain. Stillbirths were defined as fetal loss  at >28 wk of pregnancy
age, weight >1,000 g, or length of fetus >35 cm.


      Neonatal Mortality and Neonatal Respiratory Mortality, <1 Month

      Studies on PM and neonatal mortality (<1 month) included a time-series analysis of PMi0 for
4 yr of data (1998-2000) for Sao Paulo, Brazil (Lin  et  al., 2004,  095787). The analysis used daily
counts of deaths from government registries and adjusted for temporal trend, day  of the week,
weather, and holidays. Findings indicated that a 10 (ig/m3 increase in PMi0 was associated with a
1.71% (95% CI: 0.31-3.32) increase in risk of neonatal death.
      A case-crossover study of 11 yr (1989-2000) in  Southern California did not find an association
between PMi0 and neonatal deaths (Ritz et al., 2006, 089819). Quantitative results were not
provided. The authors considered adjustment for season, county, parity, gender, prenatal care, and
maternal age, education, and race/ethnicity.
      These results add to previous work on PM and neonatal death, including studies identifying
higher risk of neonatal mortality with higher TSP in the Czech Republic in an ecological analysis
(Bobak  and Leon, 1992, 044415) and case-crossover  study (Bobak  and Leon, 1999, 007678). and a
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Poisson model study in Kagoshima City, Japan (Shinkura et al., 1999, 090050). An ecological study
evaluated U.S. PMi0 data for the year 1990 using long-term pollution levels in 180 U.S. counties
(Lipfert et al., 2000, 004103). Analysis considered birth weight, sex, month of birth, location by state
and county, prenatal care, and mother's race, age, educational level, marital status, and smoking
status. County-level variables were included for socioeconomic status, altitude, and climate. Results
indicate a 13.1% increase in neonatal mortality (95% CI: 4.4-22.6) per 10 (ig/m3 PMi0 for non-low
birth weight infants. Statistically significant associations were also observed considering all infants
or low birth weight infants. However, higher levels of SO2 were associated with lower risk of infant
mortality. When sulfate and an estimate of non-sulfate particles were included in the regression
simultaneously, associations were observed with non-sulfate particles and an inverse relationship
with sulfate particles. Respiratory neonatal mortality was not associated with higher TSP in the
Czech Republic case-control study (Bobak  and Leon, 1999, 007678).


      Infant Mortality and Infant Respiratory Mortality, <1Year

     A literature search did not reveal new studies on PM  and infant mortality (<1 year) since the
previous PM AQCD. Previously conducted studies include  a case-control study that reported
associations between infant mortality and TSP levels over the period between birth and death for
infants in the Czech Republic (Bobak and Leon, 1999, 007678). An ecological study  evaluated U.S.
PMio data for the year 1990 using long-term pollution levels in 180 U.S. counties (Lipfert et al.,
2000, 004103). The authors found a 9.64% (95% CI: 4.60-14.9) increase in risk of infant mortality
for non-low birth weight infants per 10 ug/m3 increase in PMi0, a 13.4% (95% CI: -10.3 to 43.5)
increase in non-low birth weight respiratory-disease related deaths (ICD 9 460-519) and a 19.5%
(95% CI: 0.07-42.8) increase in all non-low birth weight respiratory-related infant deaths (ICD 9
460-519,769,770).


      Postneonatal Mortality and Postneonatal Respiratory Mortality, 1 Month-1 Year

      Several studies have been conducted on PM and postneonatal mortality since the previous PM
AQCD, including three from the U.S., one from Mexico, and three from Asia. Two case-control
studies examined the risk of PM to postneonatal death in California. Research focused on Southern
California for the period 1989-2000 linked birth and death certificates and considered PMi0 2 mo
prior to death with adjustment for prenatal care, gender, parity, county, season, and mother's age,
race/ethnicity,  and education (Ritz et al., 2006,  089819). As previously noted, this  study did not find
an association between PM10 and neonatal mortality (<1 month), however an association was
observed for post-neonatal mortality, with a 10 (ig/m increase in PMi0 associated  with a 4% (95%
CI:  1-6) increase in risk. The exposure period of 2 wk before death was also considered, producing
effect estimates of 5% (95% CI: 1-10) for the same PMi0 increment. Even larger effect estimates
were observed for those who died at ages 4-12 mo. When CO, NO2, and O3 were simultaneously
included with PMi0 in the model, the central estimate reduced to 2% for the 2-wk exposure period
and 4% for the 2-mo exposure period, and both estimates lost statistical significance. The other case-
control study of California considered PM2.5 from  1999 to 2000 for infants born to mothers within
five miles of a PM2 5 monitoring station (Woodruff et al., 2006, 088758). Infants who  died during  the
postneonatal period were matched to infants with date of birth within 2  wk and birth weight
category. Exposure was estimated from the time of birth to  death. Models considered parity and
maternal race,  education, age, and martial status. A 10 (ig/m3 increase in PM25 was associated with a
7% (95% CI: -7 to 24) increase in postneonatal death
     County-level PMio and PM25 for the first 2 mo of life for births in urban U.S. counties
(> 250,000  residents) from 1999 to 2002 were evaluated in  relation to postneonatal mortality with
GEE models (Woodruff et al., 2008, 098386). Births were restricted to singleton births with
gestational  age < 44 wk, same county of residence at birth and death, and non-missing data on birth
order, birth weight, and maternal race, education, and martial status. Higher levels of either PM
metric were associated with higher risk of postneonatal mortality, with 4% (95% CI: -1 to 10)
increase in mortality risk per 10 (ig/m3 in PMio and 4% (95% CI: -2 to 11) increase in mortality risk
for the same increment of PM25. This work builds on a previous study of 86 U.S. urban areas from
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1989 to 1991, finding a 4% (95% CI: 2-7) increase in postneonatal mortality per 10 (ig/m3 county-
level PMio over the first 2 mo of life (Woodruff et al., 1997, 084271).
      In Ciudad Juarez, Mexico, a case-crossover approach was applied to data from 1997 to 2001
based on death certificates and the cumulative PMi0 for the day of death and previous two days
(Romieu et al., 2004, 093074). A case-crossover study of Kaohsiung, Taiwan from 1994 to 2000
compared the average of PMi0 on the day of death and two previous days to PMi0 in control periods
a week before and week after death (Tsai et al., 2006, 090709). A similar approach was also applied
to 1994-2000 data from Taipei, Taiwan, also using case-crossover methods for the lag 0-2 PMi0 with
referent periods the week before and after death (Yang et al., 2006, 090760). In these case-crossover
studies, season was addressed through matching in the study design. A 10  (ig/m3 increase in PMi0
was associated with a 2.0% (95% CI: -2.8 to 7.0) increase in the Mexico study, a 0.59 (95% CI: -15.0
to 18.8) increase in postneonatal death in the Kaohsiung study, and a 1.02% (95% CI: -13.2 to 17.6)
increase in the Taipei study. A study in Seoul, South Korea from 1995 to 1999  used time-series
approaches adjusted for temporal trend and weather, based on national death registries excluding
accidental deaths (Ha et al., 2003, 042552). A 10 (ig/m3 increase in PMi0 was associated with a
3.14% (95% CI: 2.16-4.14) increase in risk of death for postneonates.
      A subset of the studies examining postneonatal mortality also considered the subset of
postneonatal deaths from respiratory causes. These include the time-series study in South Korea,
finding  a 17.8% (95% CI: 14.4-21.2) increase in respiratory-mortality per  10 (ig/m3 increase in PM10
(Ha et al., 2003, 042552) and the case-crossover study in Mexico, for which the same increment in
PMi0 was associated with a 1.5% (95% CI: -14.1 to 13.0) decrease in risk  (Romieu et al., 2004,
093074). Both California case-control studies identified  associations, with a 5% (95% CI: 1-10)
increase in risk in Southern California (Ritz et al., 2006,  089819) and 57.4% (95% CI: 7.0-132)
increase in California per 10  (ig/m3 PM10 (Woodruff et al., 2006, 088758). The U.S. study found this
increment in PM10 to be linked with a 16% (95% CI: 6.0-28.0) increase in respiratory postneonatal
mortality, although effect estimates for PM2.5 were not statistically significant (Woodruff et al., 2008,
098386). Earlier studies on respiratory-related postneonatal mortality include the study of 86 U.S.
urban areas, finding statistically significant effects (Woodruff et al., 1997,  084271).


      Sudden Infant Death Syndrome

      Three studies examining the relationship between  PM and sudden infant death  syndrome
(SIDS) have been published from 2002 onward. These studies examined infant mortality and were
thereby discussed in this section previously. A case-control study over a 12-year period (1989 to
2000) matched 10 controls to deaths (cases) in Southern California (Ritz et al., 2006, 089819). A
10 (ig/m3 increase in PM10 the 2 mo prior to death was associated with a 3% (95% CI: -1 to 8)
increase in SIDS. Adjusted for other pollutants (CO, NO2, and O3), the effect estimate reduced to 1%
(95%  CI: -5 to 7).
      A case-control study, also based in California, found an OR of 1.008 (95% CI:  1.006-1.012)
per 10 (ig/m3 increase in PM2.5, considering a SIDS definition of ICD 10 R95 (Woodruff et al., 2006,
088758). Due to changes in SIDS diagnosis, another SIDS  definition was explored for ICD 10 R99
in addition to ICD  10 R95. Under this SIDS definition, the effect estimate changed to 1.03 (95% CI:
0.79-1.35). The authors also examined whether the relationship between PM2.5 and SIDS differed by
season,  finding no significant difference. PMi0 and PMi0_2.5 were not associated with  risk of SIDS;
numerical results were not provided for these PM metrics. The third recent study of PM and SIDS
examined U.S. urban counties from 1999 to 2002 (Woodruff et al., 2008, 098386).  Statistically non-
significant relationships were observed between SIDS and PMi0 or PM25 in the first 2 mo of life.
      These studies add to earlier work, such as a U.S. study that found higher risk of SIDS with
higher annual PM25 levels, including in a separate analysis of normal birth weight infants (Lipfert et
al., 2000 004103). and a U.S. study identifying a 12% (95% CI: 7-17) increase in SIDS risk per
10 (ig/m3 in PMi0 for the first 2 mo of life for normal weight births (Woodruff et al., 1997, 084271).
A study based on Taiwan found  higher SIDS risk with lower visibility (Knobel et al., 1995, 155905).
whereas a 12-city Canadian time-series study identified no significant associations (Dales et al.,
2004, 087342).
      Deaths by SIDS were identified by different methods in the studies,  partly due  to transition
from ICD 9 to ICD 10 codes, but also due to different choices within the research design. Two
studies examined multiple approaches (ICD 10 R95, ICD 10 R95 and R99) (Woodruff et al., 2006,
December 2009                                  7-55

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088758: Woodruff et al, 2008, 098386). and other studies investigated ICD 9 798.0 and ICD 10 R95
(Ritz  and Wilhelm, 2008, 156914). ICD 9 798.0 (Woodruff et al., 1997, 084271). ICD 9 798.0 and
799.0 (Knobel et al., 1995, 155905). as well as a sudden unexplained death of infant <1 year for
which an autopsy did not identify a specific cause of death (Dales et al., 2004, 087342). These
variations in the definition of health outcomes add to differences in populations and study designs.
      Although some findings indicate a potential effect of PM on risk of SIDS, with the strongest
evidence perhaps from the case-control study in California (Woodruff et al., 2006, 088758). others
do not find an effect or observe an uncertain association. For the relationship between PM and SIDS,
a 2004 review article concluded consistent evidence exists compared to evidence for other infant
mortality effects  (Glinianaia et al., 2004, 087898). whereas other reviews found weaker or
insufficient evidence (Heinrich and Slama, 2007, 156534). Another review concluded that the
scientific literature on air pollution and SIDS suggests an effect, but that further research is needed to
draw a conclusion (Tong and Colditz, 2004, 087883).


      Considerations for Comparisons across Studies

      Comparison of results across studies can be challenging due to several issues, including
differences in methodologies, populations and study areas, pollution levels, and the exposure
timeframes used. Given the large variation in study designs, the methods to address  potential
confounders vary. For example, weather and season were addressed in the case-control studies by
matching, in the time-series study through non-linear functions of temperature and temporal trend,
and in the ecological study through county-level variables. All studies included consideration of
seasonality and weather. Researchers used different definitions of respiratory-related deaths,
including ICD 9 460-519 (Bobak  and Leon, 1999, 007678: Lipfert et al., 2000, 004103): ICD 9
460-519, 769-770 (Lipfert et al., 2000, 004103): ICD 9 460-519, 769, 770.4, 770.7,  770.8, 770.9,
and ICD  10 JOO-J98, P22.0, P22.9, P27.1, P27.9, P28.0, P28.4, P28.5, and P28.9 (Ritz et al., 2006,
089819): and ICD 9 460-519 and ICD 10 JOO-J99 for any  cause on death certificate  (Romieu et al.,
2004, 093074): ICD 10 JOO-99 and P27.1 excluding J69.0 (Woodruff et al., 2006, 088758: Woodruff
et al., 2008, 098386): and ICD 9 460-519 (Woodruff et al., 1997, 084271).
      Socioeconomic conditions were included at the individual level, typically maternal education,
in many studies (e.g., Bobak  and Leon, 1999, 007678: Ritz and Wilhelm, 2008, 156914: Ritz et al.,
2006, 089819: Woodruff et al., 1997, 084271: Woodruff et al., 2006, 088758) and at the community-
level in others (e.g.,  Bobak and Leon, 1992, 044415: Penna and Duchiade, 1991, 073325) or for
both individual and community-level data (e.g., Lipfert et al., 2000, 004103). The time-series
approach is unlikely to be confounded by socioeconomic and other variables that do not exhibit day-
to-day variation.  Similarly, case-crossover methods use each case as his/her own control, thereby
negating the need for individual-level confounders such as socioeconomic status (e.g., Romieu et al.,
2004, 093074: Tsai et al., 2006, 090709: Yang et al., 2006, 090760). All studies published after 2001
incorporated individual-level socioeconomic data or were of case-crossover or time-series design.
One study specifically examined whether socioeconomic status modified the PM and mortality
relationship, dividing subjects into three socioeconomic strata based on the ZIP code of residence at
death (Romieu et al., 2004, 093074). This work, based in Mexico, found that at lower  socio-
economic levels the  association between PMi0 and postneonatal mortality increased. Although the
overall association showed higher risk of death with higher PMi0 with statistical uncertainty, for the
lowest socio-economic group, a 10 (ig/m3 increment in cumulative PMi0 over the 2 days before death
was associated with  a 60% (95% CI: 3-149) increase in postneonatal death. A trend of higher effect
for lower socio-economic condition is observed in all 3 lag structures.
      Studies differ in terms of the time frame of pregnancy that was used to estimate exposure.
Exposure to PM for infant mortality (<1 yr) was estimated as  the levels between birth  and death
(Bobak and Leon, 1999, 007678). annual community levels (Lipfert et al., 2000, 004103: Penna
and Duchiade, 1991, 073325) and the 3-5 days prior to death (Loomis et al., 1999, 087288). For
neonatal deaths, exposure timeframes considered were the time between birth and death (Bobak and
Leon, 1992, 044415: Bobak and Leon, 1999, 007678). annual levels (Bobak and Leon, 1999,
007678: Lipfert et al., 2000, 004103). monthly levels (Shinkura et al., 1999, 090050).  the same day
concentrations (Lin et al., 2004, 095787). and the 2 mo or 2 wk prior to death (Ritz et  al., 2006,
089819). Postneonatal mortality was associated with PM concentrations based on annual levels
(Bobak and Leon, 1992, 044415: Lipfert et al., 2000, 004103). between birth and death (Bobak and
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Leon, 1999, 007678; Woodruff et al, 2006, 088758). 2 mo before death (Ritz et al., 2006, 089819).
the first 2 mo of life (Woodruff et al., 1997, 084271; Woodruff et al., 2006, 088758). the day of death
(Ha et al., 2003, 042552). and the average of the same day as death and previous 2 days (Romieu et
al., 2004, 093074; Tsai et al., 2006, 090709; Yang et al., 2006, 090760). Thus, no consistent window
of exposure was identified across the studies.
      PMio concentrations were highest in South Korea (69.2 (ig/m3) (Ha et al., 2003, 042552) and
Taiwan  (81.45 (ig/m3) (Tsai et al., 2006, 090709). and lowest in the U.S. (29.1 (ig/m3) (Woodruff et
al., 2008, 098386) and Japan (21.6  ug/mj)  (Shinkura et al., 1999, 090050). All studies used
community-level exposure information based on ambient monitors, as opposed to exposure
measured at the individual level (e.g., subject's home) or personal monitoring.
      Given similar sources for multiple pollutants  (e.g., traffic), disentangling the health responses
of copollutants is a challenge in the study of ambient air pollution. Several studies examined
multiple pollutants, most by estimating the effect of different pollutants through several univariate
models. Some studies noted the difficulty of separating PM effects from those of other pollutants,
but noted stronger evidence for particles than other  pollutants (Bobak  and Leon, 1999, 007678). A
few studies applied copollutant models by including multiple pollutants simultaneously in the same
model. Effect estimates for the relationship between PMi0 and neonatal deaths in Sao Paulo were
reduced to  a null effect when SO2 was incorporated (Lin et al., 2004, 095787). Associations between
PM10 and postneonatal mortality  or respiratory  postneonatal  mortality  remained but lost statistical
significance in a multiple pollutant model with CO, NO2, and O3 (Ritz et al.,  2006, 089819).
      Several review articles in recent years have examined  whether exposure to PM affects risk of
infant mortality, generally concluding that more consistent evidence has been observed for
postneonatal mortality, particularly from respiratory causes (Bobak  and Leon, 1999, 007678;
Heinrich and Slama, 2007, 156534; Lacasana et al., 2005, 155914; Sram et al., 2005, 087442). In
one review authors identified 14  studies on infant mortality and air pollution  and determined that
studies on PM and infant mortality  do not provide consistent results, although more evidence was
present for an association for some subsets of infant mortality such as  postneonatal respiratory-
related mortality (Bobak  and Leon, 1999, 007678). The relationship between PM and postneonatal
respiratory  mortality was concluded to be causal in  one review (Sram  et al., 2005, 087442). and
strong and  consistent in another (Heinrich  and Slama, 2007, 156534). Meta-analysis using inverse-
variance weighting of PM10 studies found that a 10  ug/m3 increase in acute PM10 exposure was
associated with 3.3% (95% CI: 2.4-4.3) increase in  risk of postneonatal mortality, whereas the same
increment of chronic PMi0 exposure was linked with a 4.8% (95% CI: 2.2-7.2) increase in
postneonatal mortality and a 21.6% (95% CI: 10.2-34.2) increase for respiratory postneonatal
mortality (Lacasana et al., 2005,  155914).
      Studies that examined multiple outcomes and ages of death allow a direct comparison based
on the same study population and methodologies, thereby negating the concern that inconsistent
results are due to underlying variation in population, approaches, etc. In this review,  one study, based
in Southern California identified no association for  neonatal  effects (numerical results not provided)
but statistically significant results for postneonatal mortality  (Ritz et al., 2006, 089819). Figure
7-5compares risk for the postneonatal period for respiratory  and total mortality. In six of the seven
studies,  higher effect estimates were observed for respiratory-related mortality. Results from the
neonatal period found higher effects for total mortality compared to respiratory mortality (Bobak
and Leon, 1999, 007678) and the reverse for a study examining infant  mortality (Lipfert et al., 2000,
004103). Thus, there exists evidence for a stronger effect at the postneonatal  period and for
respiratory-related mortality, although this  trend is not consistent across all studies.
December 2009                                  7-57

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                        20

                       Neonatal
                                 40
                                          60
                                                                                         60
Figure 7-5.     Percent increase in postneonatal mortality per 10 ug/m3 in PMio, comparing risk
               for total and respiratory mortality. Panel a (left) provides central estimates; panel
               b (right) also adds the 95% intervals. The points reflect central estimates and the
               lines the 95%  intervals. Solid lines represent statistically significant effect
               estimates; dashed lines represent non-statistically significant estimates.1
7.4.1.6.   Decrements in Sperm Quality

      Limited research conducted in the Czech Republic on the effect of ambient air pollution on
sperm production has found associations between elevated air pollution and decrements in
proportionately fewer motile sperm, proportionately fewer sperm with normal morphology or normal
head shape, proportionately more sperm with abnormal chromatin (Selevan et al., 2000, 012578).
and an increase in the percentage of sperm with DNA fragmentation (Rubes et al., 2005, 078091).
These results were not specific to PM, but for exposure to a high-, medium- or low-polluted air
mixture.  Similarly, in Salt Lake City, Utah, PM2.5 was associated with decreased sperm motility and
morphology (Hammoud et al., 2009, 192156). Research in Los Angeles, California examined 5,134
semen samples from 48 donors in relation to ambient air pollution measured 0-9, 10-14, 70-90 days
before semen collection over a 2-yr period (1996-1998). Ambient O3 during all exposure periods had
a significant negative correlation with average sperm concentration, and no other pollutant measures
were significantly associated with sperm quality parameters,  or presented quantitatively (Sokol et al.,
2006, 098539).


7.4.2.  lexicological Studies

      This section summarizes recent evidence on reproductive health effects reported with exposure
to ambient PM; no evidence was presented in this area in the 2004 PM AQCD. Studies from
different toxicological rodent models  allow for investigation  of specific mechanisms and modes of
1 Studies included are Bobak and Leon (1999, 007678). Ha et al. (2003, 042552). Ritz et al. (2006, 089819). Romieu et al. (2004, 093074).
 Romieu et al. (2008, 156922). Woodruff et al. (1997, 084271). Woodruff et al. (2006, 088758). Findings from Bobak and Leon (1999,
 007678) were based on TSP and were converted to PMio estimates assuming PMio/TSP = 0.8 as per summary data in the original article
 (Bobak and Leon, 1999, 007678). Findings from Woodruff et al. (1997, 084271) for respiratory-related mortality were based on non-low
 birth weight infants. Results for Woodruff et al. (2006, 088758) were based on PM2.5 and were converted to PMio assuming
 PM2.5/PM10 = 0.6.
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action for reproductive changes. Emphasis is placed here on results from different windows of
development, i.e., exposure in utero, neonatally or as an adult can affect reproductive outcomes as an
adult. In addition, studies evaluating whether fertility is affected in female and/or male animals by a
similar exposure, and how  exposures are transmitted to the fertility of the F i offspring, are
summarized. Hormonal changes which can lead to decreased sperm count or changes in the estrous
cycle are also of interest. Studies of pregnancy losses and placental sufficiency are also reported.
Most recently, the role of environmental chemicals in shifting sex ratios (also seen in epidemiologic
studies) and in affecting heritable DNA changes have become outcomes of interest.


7.4.2.1.   Female Reproductive Effects



     Urban Air

     Windows of exposure are important in determining reproductive success as an adult. Exposure
as a neonate may have a drastically different impact than does a similar adult exposure. To test this,
female BALB/C mice were exposed to ambient air in Sao Paulo as neonates or as adults and then
were bred to non-exposed males (Mohallem et al., 2005,  088657). Ambient concentrations of the
pollutants CO, NO2 PNV and SO2 were 2.2 ± 1.0 ppm, 107.8 ± 42.3 ^g/rn3, 35.5 ± 12.8 j-ig/m3,
and 11.2 ± 5.3 |J,g/m , respectively. They reported decreased fertility in animals exposed as
newborns, but not in adult-exposed female BALB/c mice. There were a significantly higher number
of liveborn pups from dams housed in filtered chambers (PM and gaseous components removed)
versus animals exposed to ambient air as newborns. There was also a higher incidence of
implantation failures in dams reared as newborns in polluted chambers. Sex ratio, number of
pregnancies per group, resorptions, fetal deaths, and fetal placental weights did not differ
significantly by exposure group. Thus, in these studies, exposure to ambient air pollution affected
future reproductive success of females if they were exposed as neonates and not  if exposed as adults.


     Diesel  Exhaust

     Significant work has been done in male rodent models to determine the effect of PM exposure
on reproductive outcomes,  with fewer studies conducted  using female rodents. Tsukue et al. (2004,
096643) exposed pregnant  C57-BL mice to DE (0.1 mg/m3) or to clean air (controls) for 8 h/day
from GD2-13. The concentration of the gaseous materials including NO, NOX, NO2, CO and SO2
are 2.2 ±  0.34 ppm, 2.5  ± 0.34 ppm, 0.0 ppm, 9.8 ± 0.69 ppm, and <0.1  ppm (not detectable),
respectively. At GD14 female fetuses were collected for analysis of mRNAfor two genes involved in
sexual differentiation (Ad4BP-l/SF-l and MIS), and found no significant changes. Work by Yoshida
et al. (2006, 097015) showed changes in these two transcripts in male ICR fetuses exposed to similar
concentrations of DE, albeit with different daily durations of exposure. Further work by Yoshida et
al. (2006, 097015) showed that of three mouse strains tested, ICR male fetuses were the most
sensitive  to DE-dependent  changes in these two genes. Nonetheless, strain sensitivity to DE particles
may  also differ by sex. Thus, it appears that female mice  exposed in utero to DE show a lack of
response  at the mRNA level of MIS or Ad4bP-l/SF-l,  important genes in male sexual differentiation
that showed DE-dependent changes in male pups from dams exposed in utero. Female fetuses have
shown a decrease in BMP-15, which is related to oocyte development (Tsukue et al., 2004, 096643).
     A sensitive measure of androgenic activity in male rodents is anogenital distance (AGD), i.e.,
decreased AGD is seen  with exposure to anti-androgenic environmental chemicals, the phthalates
(Foster et al.,  1980, 094701: Foster et al., 2001, 156442). To assess the role of DE exposure on
reproductive success and anti-androgenic effects on offspring, Tsukue et al. (2002, 030593) exposed
6 week-old female C57-B1  mice to 4 mo of DE (0.3, 1.0,  or 3.0 mg/m3;  PM MMAD of 0.4 urn) or
filtered air.  DE-exposed estrous females had significantly decreased uterine weight (1.0 mg/m ).
Some of the DE-exposed females were bred to unexposed males and DE-exposure led to increased,
albeit not significantly increased, rates of pregnancy loss in mated females (up to 25%). Offspring
were weighed after birth and decreases in body weight were observed at 6 and 8  wk (males and
females,  1.0 and 3.0 mg/m3) and 9 wk (females, 1.0 and 3.0 mg/m3). Anogenital  distance was
decreased in 70-day old DE-exposed male offspring (0.3  mg/m3). In female offspring at 70 days of
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age, lower organ weights (adrenals, liver and thymus) were observed (1.0 mg/m3) compared to
controls; thymus weight of the 0.3 mg/m females was also lower at 70 days. Crown to rump length
in females from dams exposed to DE (1.0 and 3.0 mg/m3) was less than the control group. In
conclusion, adult exposure to DE led to maternal-dependent reproductive changes that affected
outcomes in offspring that manifested as decreased pup body  weight, anti-androgenic effects like
decreased AGD and decreased organ weight (which may have been confounded by changes in body
weight because weights were not reported as relative organ weights).


7.4.2.2.   Male Reproductive Effects


      Diesel Exhaust

      Studies were performed to determine PM-dependent strain sensitivity of the male reproductive
tract using male steroidogenic enzymes as the model pathway. Three strains of pregnant mice (ICR,
C57B1/6J or ddY mice) were continuously exposed to DE at 0.1 mg/m3 via inhalation or clean air
over gestational days 2-13 (Yoshida et al., 2006, 156170). At  GDI4, dams were euthanized and
fetuses were collected. Male fetuses were collected from each dam for mRNA analysis of genes
related to male gonad development including Mullerian inhibiting substance (MIS; crucial for sexual
differentiation including Mullerian duct regression in males),  steroid transgenic factor (Ad4BP/SF-l,
an enzyme in the testosterone synthesis pathway), cytochrome P450 cholesterol side chain cleavage
enzyme (P450scc), and other steroidogenic enzymes [17(3-hydroxysteroid dehydrogenase (HSD),
cytochrome P450 17-a-hydroxylase (P450cl7), and 3-|3hydroxysteroid dehydrogenase (3(3HSD)].
There were significant decreases in MIS (ICR and C57BL/6 mice) and Ad4BP/SF-l (ICR mice)
compared to the control groups. The ddY strain demonstrated no changes in Ad4BP/SF-l or MIS,
which may be due to marked changes in 3(3-hD expression compared to non-DE exposed controls.
From these studies, it appears that mouse strains with in utero exposure to DE show differential
sensitivity in gonadal differentiation genes (mRNA) expression in male offspring; ICR are the most
sensitive, followed by C57BL/6, with ddY mice being the least sensitive.
      Yoshida et al. (2006, 097015) also monitored changes in the male reproductive tract after in
utero exposure to DE. Timed-pregnant ICR dams were exposed during gestation (2 days post-coitus
[dpc]-16 dpc) to continuous DE (0.3, 1.0 or 3.0 mg/m3) or clean air. The reproductive tracts of male
offspring were monitored at 4 wk postnatally. These pups received possible continued exposure
through lactation as dams were exposed to DE  during gestation and nursed pups. Exposure to 0.3
mg/m  of DE had no effect on male reproductive  organ weight or serum testosterone. The
intermediate concentration of 1.0 mg/m3 induced increases in serum testosterone.  Exposure to the
higher concentration (1.0 and 3.0 mg/m3) of DE led to significant increases in reproductive gland
weight (testis, prostate, and coagulating gland). The organ weights are presented as absolute numbers
and not adjusted for body weight, which is sometimes problematic for complete representation of
hormonal changes, as body weight may confound absolute organ weight changes. Transcripts
relating to male sexual differentiation (MIS and AD4BP/SF-1, 1.0 and 3.0 mg/m3) were also
significantly decreased. Sexual differentiation is a tightly regulated process and these changes in
transcription may lead to changes that can affect genitalia development.
      The effects of DE exposure on male spermatogenesis have also been demonstrated. Exposure
of pregnant ICR mice to DE (2-16 dpc continuous inhalation  exposure to 1.0 mg/m3 or filtered clean
air) led to impaired spermatogenesis in offspring  (Ono et al., 2007, 156007). Male offspring were
followed at PND 8,  16, 21 (3 wk), 35 (5  wk) and  84 (12 wk).  After 16 dpc, but before termination of
the study, all of the animals were transferred to a  regular animal care facility and received clean air
exposure until the termination of the study. No cross  fostering was performed in this experiment, so
pups that were born to DE-exposed dams were also nursed on these dams and may have received
lactational exposure to DE. The gaseous components of the diluted DE included NO, NO2, SO2, and
CO2 at concentrations of 11.75 ±  1.18, 4.62 ± 0.36, 0.21 ± 0.01, and 4922 ± 244 ppm, respectively.
Body weight was significantly depressed at PNDs 8 and 35. Accessory gland relative weight was
significantly increased at PND8 and PND 16 only. Serum testosterone was significantly decreased at
3 wk and was significantly increased at 12 wk. At 5 and 12  wk, daily sperm production (DSP) was
significantly decreased. FSH receptor and StAR mRNA levels were significantly increased at 5 and
12 wk, respectively. Relative testis weight and  relative epididymal weight were unchanged at all
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time points. Histological changes showed sertoli cells with partial vacuolization and a significant
increase in testicular multinucleated giant cells in the seminiferous tubules of DE-exposed animals
compared to control. This study indicates that in utero exposure to DE had effects on
spermatogenesis in offspring at the histological, hormonal and functional levels.
      In utero exposure to DE and its effect on adult body weight, sex ratio, and male reproductive
gland weight was measured by Yoshida et al. (2006, 097015). Pregnant ICR mice were exposed by
inhalation to DE (0.3, 1.0 or 3.0 mg/m3) or clean air from 2 dpc to 16 dpc. Pups were allowed to
nurse in clean air on exposed dams until weaning and at PND28, male pups were sacrificed. At this
time, serum testosterone and pup reproductive gland weight was determined. Significant increases in
relative reproductive organ weights were reported at 1.0 and 3.0 mg/m3 for the seminal vesicle,
testis, epididymis, coagulating gland, prostate and liver. Male pup serum testosterone was
significantly increased at 1.0 mg/m3.  Mean testosterone positively correlated with testis weight, DSP,
aromatase and steroidogenic enzyme message levels (P450cc, c!7 lyase, and P450 aromatase). Sex
ratio did not differ in DE-exposed animals versus control. Male pup body weight of DE-exposed
animals was significantly increased at PND28 (1.0 and 3.0 mg/m3). These studies show that in utero
DE-exposure led to increased serum testosterone and increased reproductive gland weight in male
offspring early in life.
      The effects of DE on murine adult male reproductive function were studied by exposing ICR
male mice (6 wk of age) to DE (clean air control, 0.3, 1.0 or 3.0 mg/m3) for 12 h/day for 6 mo with
another group receiving a 1-mo recovery of clean air post-exposure (Yoshida and Takedab, 2004,
097760). After 6 mo of DE exposure, there was a concentration-dependent increase in degeneration
of seminiferous tubules and a decrease in DSP/g of testis tissue. After 6 mo exposure to DE particles
plus 1 mo of recovery in clean air, significant decreases remained in DSP at the two highest
concentrations. The effect of ingestion  of deposited PM on the fur with grooming cannot be ruled out
as a possible exposure pathway in this experiment.
      To expand on PM-dependent changes in spermatogenesis, an eloquent DE-exposure model
was designed to determine if PM or the gaseous phase of DE was responsible for changes in sperm
production in rodents (Watanabe, 2005. 087985). Pregnant dams (F344/DuCrj rats) exposed to DE
(6 h/day exposure to 0.17 or 1.71 mg/m ; <90% of PM less than 0.5 um; NO2 concentrations 0.10
and 0.79 ppm, respectively) or filtered  air (removing PM only, low concentration filtered air and
high concentration filtered air) from GD7 to parturition produced adult male offspring with a
decreased number of sertoli cells and decreased DSP (PND 96) when compared to control mice
exposed to clean air. The concentrations of NO2 for the low and high filtered exposure groups were
0.1  and 0.8 ppm, respectively. Because both PM-filtered and DE-exposure groups showed the same
outcomes, the effects are likely due to gaseous components of DE.


      Motorcycle Exhaust

      Adult male (8-wk old) Wistar rats were exposed to motorcycle exhaust (ME) for 1 h in the
morning and  1 h in the afternoon (5 day/wk) at 1:50 dilution for 4 wk (group A), 1:10 dilution for
2 wk (group B)  or 4 wk (group C), or to clean air (Huang et al., 2008, 156574). After 4 wk of
exposure, both exposed groups had significantly decreased body weight compared to the control
group. All three ME exposure groups showed a decreased number of spermatids in the testis. Both
1:10 exposure groups also demonstrated decreased caudal epididymal sperm counts. Group C had
significant decreased testicular weight, decreased mRNA expression for the cytochrome P450
substrate 7-ehtoxycoumarin O-de-ethylase, and increased IL-6, IL-lp, and COX-2 mRNA levels.
Decreased protein levels of the antioxidant, superoxide dismutase, and increased IL-6 protein were
reported for group C when compared to control. In addition, serum testosterone was significantly
decreased in group C. Co-treatment with the antioxidant vitamin E resulted in partial attenuation of
serum testosterone levels and caudal  epididymal sperm counts, and returned IL-6, IL-1(3, and COX-2
ME exposure-dependent message levels to baseline. The glutathione antioxidant system and lipid
peroxidation were unchanged. In conclusion, male animals exposed to ME showed significant
decrements in body weight, spermatid number, and serum testosterone with an increase in
inflammatory cytokines. Vitamin E co-treatment with ME-exposure led to an attenuation of
inflammation and a partial rescue of testosterone levels and sperm numbers.
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      Summary of Toxicological Study Findings for Male Reproductive Effects

      In summary, laboratory animals exposed to DE in utero or as adults manifest with abnormal
effects on the male reproductive system. In utero exposure to DE induced increased reproductive
gland weight and increased serum testosterone in early life (PND28), which may lead to early
puberty (albeit not measured in this study). With similar in utero DE exposures, later life outcomes
include decreased DSP, aberrant sperm morphology, and hormonal changes (testosterone and FSHr
decrements). Chronic exposure of adult mice to DE also induced decreased DSP and seminiferous
tubule degeneration. DE-dependent effects on male reproductive function have been reported in
multiple animal models, with only one model separating exposure based on particulate versus
gaseous components. DE and filtered air (gaseous phase only) exposure in utero induced sertoli cell
and DSP  decrements in both groups, indicating that the gaseous phase of DE was causative. Adult
male rats exposed to ME manifested with decreased spermatid number, serum testosterone, and an
increase in inflammatory cytokines. Significant effects on the male reproductive system have been
demonstrated after exposure to ambient PM sources (DE or ME). Nonetheless, these models often
include a complex mixture of gaseous component and PM exposure, which makes interpreting the
contribution from PM alone difficult.


7.4.2.3.  Multiple Generation Effects



      Urban Air

      Veras et al. (2009, 190496) investigated pregnancy and female reproductive outcomes in
BALB/c female mice exposed to ambient air or PM-filtered ambient air at one of two different time
periods (before conception and during pregnancy) near an area of high traffic density in Sao Paulo,
Brazil. Exposures were 27.5 and 6.5 ug/m  PM2.5 for ambient and PM-filtered air chambers,
respectively, with 101 ug/m3 NO2, 1.81 ug/m3 CO, and 7.66 ppm SO2  in both chambers. Two groups
of 2nd generation (G2) nulliparous female mice were continuously exposed from birth. Estrous
cyclicity  and ovarian follicle classification were followed at PND60 (reproductive maturation) in one
group. A  further group was subdivided into four groups by exposures during  pregnancy following
reproductive capability  and pregnancy outcomes of the G2 mice. Animals exposed to ambient air
versus PM-filtered air had an extended time in estrous and thus, a reduction in the  number of cycles
during the study period. The number of antral follicles was significantly decreased in the ambient air
versus the PM-filtered air animals. Other follicular quantification (number of small, growing or
preovulatory follicles) showed no differences between the two chambers. There was an increase in
the time necessary for mating, a decrease in the fertility index, and an  increase in the pregnancy
index in the ambient air group versus the PM-filtered group. Specifically, in the ambient air groups,
there was a significant increase in rate of the post-implantation loss in Gl and G2 groups. However,
there was no statistically significant change in number of pups in the litter. Fetal weight was
decreased in all treatment groups (ambient air groups Gl and G2, and  PM-filtered G2) when
compared to the PM-filtered Gl group  or animals  raised entirely in filtered air, showing that fetal
weight was affected by  both pre-gestational and gestational PM exposure.
      PM exposure prior to conception is associated with increased time in estrous, which in other
animal models can be related to ovarian hormone dysfunction and ovulatory  problems. These estrous
alterations can contribute to fecundity issues. There was no significant difference in number of
preovulatory follicles in the above model, but there was a statistically  significant decrease in the
number of antral follicles (Veras et al., 2009, 190496). Antral follicles are the last stage in follicle
development prior to ovulation, and a decrease in antral follicle number can be related to premature
reproductive senescence, premature ovarian failure, or early menopause, which were not followed in
this study.
      In this study (Veras et al., 2009, 190496). the males that were used to generate the Gl  and G2
groups were also exposed to ambient air or PM-filtered ambient air, and thus the reproductive
contribution of these males to the overall fertility and mating changes  in the females cannot be
totally eliminated as a possible confounder to the observed effects.  Thus, these effects are hard to
differentiate  as male- or female-dependent and likely indicate a general loss of reproductive fitness.
Interestingly, both pre- and gestational  exposure to ambient air induced a significant loss in post-
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implantation of fetuses and this may be related to placental insufficiency as has been described in
other work by this lab (Veras et al., 2008, 190493).


7.4.2.4.   Receptor Mediated Effects



     Arylhydrocarbon Receptor (AhR)


     Diesel Exhaust Particles

     The AhR is often activated by chemicals classified as endocrine disrupting compounds
(EDCs), exogenous chemicals that behave as hormonally active agents, disrupting the physiological
function of endogenous hormones. DE particles are known to activate the AhR. A recent study by
Izawa et al. (2007, 190387) showed that certain polyphenols (quercetin from the onion) and food
extracts (Ginkgo biloba extract) are able to attenuate DE particle-dependent AhR activation when
measured with the Ah-Immunoassay, thus possibly attenuating the EDC activity of DE particles.


7.4.2.5.   Developmental Effects


     Sex Ratio


     Urban Air

     A correlation between PM10 exposure and a decrease in standardized sex ratios (SSRs) has
been reported in humans  exposed to air pollution (Lichtenfels et al., 2007, 097041; Wilson et al.,
2000, 010288). with fewer numbers of male births reported. To understand this shift, two groups
(control and exposed) of male Swiss mice were housed concurrently in Sao Paulo and received either
ambient air exposure or filtered air (chemical and particulate filtering) from PND10 for 4 mo
(Lichtenfels et al., 2007,  097041). Filtration efficiency for PM2.5,  CB, and NO2 inside the chamber
was found to be 55%, 100%, and 35%, respectively. After this exposure, non-exposed females were
placed in either chamber to mate. After mating, the males were sacrificed and testes collected; males
exposed to ambient air showed decreased testicular and epididymal sperm counts, decreased total
number of germ cells, and decreased elongated spermatids, but no significant change in litter size.
Females were housed in the chambers and sacrificed on GD19 when the number of pups born alive
and the sex ratio were obtained. There was a significant decrease  in the SSR for pups born after
living in the ambient air-exposed chamber compared to the filtered chamber. In this study, a shift in
SSR has been shown for  both humans and rodents exposed to air  pollution, but other studies with DE
exposure (Yoshida et al.,  2006, 156170) or ambient air in Sao Paulo (Mohallem et al., 2005, 088657)
showed no changes in rodent sex ratio. Possible exposure to PM and other components of ambient
air via ingestion during grooming cannot be ruled out in this rodent model.


     Immunological Effects: Placenta


     Diesel Exhaust

     Placental insufficiency can lead to the loss of a pregnancy or to adverse fetal outcomes. DE-
exposure has been shown to induce inflammation in various models. Fujimoto et al. (2005, 096556)
assessed cytokine/immunological changes of DE-dependent inhalation exposure on the placenta
during pregnancy. Pregnant Slc:CR mice were exposed to DE (0.3, 1.0, or 3.0 mg/m3; PM MMAD
of 0.4 (im) or clean air from 2 to 13 dpc and dams, placenta,  and pups were collected at 14 dpc.
There was a significant increase in the number of absorbed placentas in DE-exposed animals (0.3
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and 3.0 mg/m3) with a significant decrease in the number of absorbed placentas in DE-exposed
animals at the middle concentration (1.0 mg/m3). Absorbed placentas from DE exposed mice had
undetectable levels of CYP1A1 and twofold increases in TNF-a; CYP1A1 placental mRNAfrom
healthy placentas of DE-exposed mice was unchanged versus control. IL-2, IL-5, IL-12a, IL-12B and
GM-CSF mRNA significantly increased in placentas of DE-exposed animals (0.3 and 3.0 mg/m ).
Fujimoto et al. (2005, 096556) reported DE-induced significant increases in multiple inflammatory
markers in the placenta with significant increases in the number of absorbed placentas.


      Immunological Effects: Asthma


      Model Particles

      In utero  exposure may confer susceptibility to PM-induced asthmatic responses in offspring.
Exposure of pregnant BALB/c mice to aerosolized ROFA leachate by inhalation or to DE particles
intranasally increases asthma susceptibility to their offspring (Fedulov et al., 2008, 097482; Hamada
et al., 2007, 091235). The offspring from dams exposed for 30 min to 50 mg/mL ROFA 1, 3, or
5 days prior to delivery responded to OVA immunization and aerosol challenge with airway
hyperreactivity and increased antigen-specific IgE and IgGl antibodies (Hamada et al., 2007,
091235). Airway hyperreactivity was also observed in the offspring of dams intranasally instilled
with 50 (ig of DE particles or TiO2, or 250 (ig CB, indicating that the same effect could be
demonstrated using relatively "inert" particles (Fedulov et al., 2008, 097482). Pregnant mice were
particularly sensitive to exposure to DE or TiO2 particles, and genetic analysis indicated differential
expression of 80 genes in response to TiO2 in pregnant dams. Thus pregnancy and in utero exposure
may enhance responses to PM, and exposure to even relatively inert particles may result in offspring
predisposed to asthma.


      Placental Morphology


      Urban Air

      Exposure to ambient air pollution during pregnancy is associated with reduced fetal weight in
both human and animal models. The effect of particulate urban air pollution on the functional
morphology of the mouse placenta was explored by exposing second generation mice in one of four
groups to urban Sao Paulo air (PM was 67% PM2.5, mainly of vehicular  origin) or filtered air (Veras
et al., 2008, 190493). Experimental design was: group F-F comprised of mice that were raised in
filtered air chambers and completed pregnancy in filtered air chambers;  group F-nF raised in filtered
air and pregnant in ambient air; group nF-nF raised and completed pregnancy in non-filtered air
chambers; and group nF-F mice raised in ambient air and received filtered air during pregnancy.
Mean PM25 concentrations in the F  and nF chambers were 6.5 and 27.5  (ig/m3, respectively.
Exposure was from PND20-PND60. After this exposure, the animals were mated and then
maintained in their respective chambers during pregnancy. Pregnancy was terminated at GD8 (near
term) with placentas and fetuses collected for analysis.
      Exposure to ambient PM pre-gestationally or gestationally led to significantly smaller fetal
weight (total litter weight). Pregestational exposure to ambient air induced significant increases in
fetal capillary surface area and total mass-specific conductance, but this  may be explained by
reduced maternal/dam blood space and diameters. Gestational exposure  to non-filtered air was
associated with reduced volume, diameter (caliber) and surface area of maternal blood space with
compensatory greater fetal capillary surface  and oxygen diffusion conduction rates. Intravascular
barrier thickness, a quantitative relationship between trophoblast volume and the combined surfaces
of maternal blood spaces and fetal capillaries, was not reduced with ambient air exposure. This study
provides evidence that fetal/piacental circulatory adaptation to maternal  blood deficits after ambient
PM exposure may not be sufficient to overcome PM-dependent birth weight deficits in mice exposed
to ambient air, with the magnitude of this effect greater in the gestationally-exposed groups.
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      Placenta! Weights and Birth Outcomes


      Urban Air

      Pregnant female Swiss mice were exposed to ambient air (Sao Paulo) or filtered air over
various portions of gestation to determine if there was an association between fetal or placental
weight or birth outcomes with exposure to air pollution (Rocha et al., 2008, 096685). The reported
ambient concentrations of PMi0 (42 ± 17 ug/mi ), NO2 (97 ± 39 ug/m3), and SO2 (9 ± 4 ug/mi ) were
measured 100 m away from the rodent exposure chambers. By using six time windows of exposure
that covered 1-3 wk of gestation (the entire gestation period in a mouse), a significant decrease in
near-term fetal weight (GDI9) was induced by  ambient air-exposure during the first week of
gestation. Decreased placental weight could be induced by ambient air exposure during any of the
3 wk of gestation. This study points to possible windows of exposure that may be important in
evaluating epidemiologic  study results.


      Neurodevelopmental Effects


      Diesel Exhaust

      The diagnosis of autism is on the rise in the Western world with its etiology mostly unknown.
Autism-associated cell loss is brain region-specific and hypothesized to be developmental in origin.
Sugamata et al. (2006, 097166) exposed pregnant ICR mice to DE (0.3 mg/m3) continuously from
2 dpc to 16 dpc. Pups with in utero exposure to DE were nursed in clean air chambers, but may have
received gastro-intestinal  exposure via lactational transfer of various components  of DE. At 11 wk of
age, cerebellar brain tissue was collected. Earlier work has shown that DE particles (<0.1 urn) have
been detected in the brains (cerebral cortex and hippocampus) of newborn pups who were born to
dams  exposed to DE during pregnancy  (Sugamata et al., 2006, 097166). Histological analysis of DE-
exposed pup cerebella revealed significant increases in caspase-3 (c-3) positive cells compared to
control and significant decreases in cerebella Purkinje cell numbers in DE-exposed animals versus
control. The ratio of cells  positive for apoptosis (c-3 positive) showed a nearly significant sex
difference with males displaying increased apoptosis versus females (p = 0.09). In humans with
autism, the cerebellum has a decreased number of Purkinje cells, which is thought to be fetal and
developmental in origin; further, these authors speculate that humans may be more sensitive to DE-
dependent neuronal brain  changes, as the human placenta is two-layers thick compared to the mouse
placenta that is four layers thick.


      Behavioral Effects
      Diesel Exhaust Particles

      Body weight decrements at birth have recently been associated through the Barker hypothesis
with adverse adult outcomes. Thus, many publications have begun to focus on decreased birth
weight for gestational age and associated adult changes. Hougaard et al. (2008, 156570) exposed 40
timed-pregnant C57BL/6 dams to DE particles reference materials (SRM 2975) via inhalation over
GD7-GD19 of pregnancy. They found significantly decreased pup weight at weaning, albeit not at
birth. PM-dependent liver changes were monitored by following various inflammatory and
genotoxicity-related mRNA transcripts and there were no significant differences in pups at PND2.
The comet assay from PND2 pup livers showed no significant differences in DNA damage between
DE particle-exposed and control animals. The prohormone, thyroxine, was unchanged in control and
DE particle-exposed dams and offspring at weaning. At 2 mo, female DE particle-exposed pups
required less time than controls to locate the platform in its new location during the first trial of the
spatial reversal learning task in the Morris water maze. Thus, DE particle exposure during in utero
development led to behavioral changes without  body weight at weaning or changes in inflammatory
markers or thyroid hormone levels.
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      Diesel Exhaust
      The effect of in utero DE exposure on CNS motor function was evaluated in male pups (ICR
mice) after dams received DE exposure (8h/d><5d/wk) from GD2-GD17 (Yokota et al., 2009,
190518). The exposure atmosphere contained concentrations of 1.0 mg/m3 for particle mass,
2.67 ppm CO, 0.23 ppmNO2, and <0.01 ppm SO2. Spontaneous motor activity was significantly
decreased in pups  (PND35), as was the dopamine metabolite homovanillic acid measured in the
striatum and nucleus accumbens, indicating decreased dopamine (DA) turnover. However, DA levels
were unchanged in the same areas of the brain. The authors conclude that these data demonstrate that
maternal exposure to DE induced hypolocomotion, similar to earlier studies with adult and neonatal
DE particle exposure (Peters et al., 2000, 001756). with decreased extracellular DA release.


      Lactation
      Diesel Exhaust

      Tozuka et al. (2004, 090864) monitored the transfer of PAHs to fetuses and breast milk of
F344 rats exposed to DE (6h/day) for 2 wk from GD7-GD 20 (minus 4 days for the weekend when
no exposure occurred) with PMi0 concentration of 1.73 mg/m3. At PND 14, breast milk was
collected. Fifteen PAHs were monitored in the DE exposure chamber and seven were quantified in
dam blood with levels of phenanthrene (Phe), anthracene (Ant) and benz[a]anthracene (BaA) in the
DE group being significantly higher than the control group. In breast milk, Ant, fluoranthene (Flu),
pyrene (Pyr), and chrysene (Chr) showed significant increases in the DE group compared to the
control group. BaA tended to be about fourfold higher than the control group in breast milk, but the
increase was not significant. PAHs in dam livers of DE versus control were not significantly
different. The results of this study demonstrate that PAHs derived from DE are transferred across the
placenta from the DE-exposed dam to the fetus. Lactational transfer through the breast milk is also
likely as PAHs were detected in dam breast milk, but this should be confirmed in future studies that
cross foster control and exposed dams and pups. The lipophilicity of the PAH based on its structure
likely affected its uptake in the dam, as PAHs with 3 or 4 rings were found in maternal blood and
PAHs with 5 or 6 rings were not detected.


      Heritable DMA Changes and Epigenetic Changes


      Ambient Air

      To address the role of ambient air exposure on heritable changes, Somers et al. (2004, 078098)
exposed mice to ambient air in at a rural Canadian site or at an urban site near a steel mill. They
showed that offspring of mice exposed to ambient air in urban regions inherited paternal-origin
expanded simple tandem repeat (ESTR) mutations 1.9-2.1 times more frequently than offspring of
mice exposed to HEPA filtered air or those exposed to rural ambient air. Mouse expanded simple
tandem repeat (ESTR) DNA is composed of short base pair repeats which are unstable in the
germline and tend to mutate by insertion or deletion of repeat units. In vivo and in situ studies have
shown that murine ESTR loci are susceptible to ionizing radiation, and other environmental
mutatgen-dependent germline mutations, and are thus good markers of exposure to environmental
contaminants.
      Expanding upon the above work and to determine if PM or the gaseous phase of the urban air
was responsible for heritable mutations, Yauk et al. (2008, 157164) exposed mature male
C57BlxCBA Fl hybrid mice to either HEPA-filtered air or to ambient air in Hamilton, Ontario,
Canada for 3 or 10 wk, or 10 wk plus 6 wk of clean air exposure (16  wk). Sperm DNA was
monitored for expanded simple tandem repeat (ESTR) mutations. In addition, male-germ line
(spermatogonial stem cell) DNA methylation was monitored post-exposure. This area in Hamilton is
near two steel mills and a major highway. Air quality data provided by the Ontario Ministry of the
Environment showed the highest concentrations of TSP and metals at week 4 (93.8 ±17  and
3.6 ± 0.7 (ig/m3, respectively) and PAH at week 3 (8.3 ± 1.7 ng/m3). Mutation frequency at ESTR
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Ms6-hm locus in sperm DNA from mice exposed 3 or 10 wk did not show elevated ESTR mutation
frequencies, but there was a significant increase in ESTR mutation frequency at 16 wk in ambient
air-exposed males versus HEPA filter-exposed animals, pointing to a PM-dependent mechanism of
action. When compared to HEPA filter air-exposed males, ambient air-exposed males manifested
with hypermethylation of germ-line DNA at 10 and 16 wk. These PM-dependent epigenetic
modifications (hypermethylation) were not seen in the halploid stage (3 wk) of spermatogenesis, but
were nonetheless seen in early stages of spermatogenesis (10 wk) and remained significantly
elevated in mature sperm even after removal of the mouse from the environmental exposure (16 wk).
Thus, these studies indicate that the ambient PM phase and not the gaseous phase is  responsible for
the increased frequency of heritable DNA mutations and epigenetic modifications.


7.4.3.  Summary and Causal Determinations



7.4.3.1.   PM2.5

      The 1996 PM AQCD concluded that while few studies had been conducted on the link
between PM and infant mortality, the research "suggested an association," particularly for post-
neonates (U.S. EPA, 1996, 079380).  In the 2004 PM AQCD, additional evidence was available on
PM's effect on fetal and  early postnatal development and mortality and while some studies indicated
a relationship between PM and pregnancy outcomes, others did not (U.S. EPA, 2004, 056905).
Studies identifying associations found that exposure to PMi0 early during pregnancy (first month of
pregnancy) or late in the pregnancy (6 wk prior to birth) were linked with higher risk of preterm
birth, including models adjusted for other pollutants, and that PM2.5 during the first month of
pregnancy was associated with IUGR. However, other work did not identify relationships between
PMio exposure and low birth weight. The state of the science at that time, as indicated in the 2004
PM AQCD, was that the research provided mixed results based on studies from multiple countries.
      Building on the evidence characterized in the previous AQCDs, recent epidemiologic studies
conducted in the U.S. and Europe were able to examine the  effects of PM25, and all found an
increased risk of low birth weight (Section 7.4.1). Exposure to PM2.5 was usually associated with
greater reductions in birth weight than exposure to PM^. All of the studies that examined the
relationship between PM2.5 and preterm birth report positive associations, and most were statistically
significant. The studies evaluating the association between PM2 5 and growth restriction all found
positive associations, with the strongest evidence coming when exposure was assessed during the
first or second trimester (Section 7.4.1). For infant mortality (<1 yr), several studies  examined PM25
and found positive associations (Section 7.4.1).
      Animal toxicological studies reported effects including decreased uterine  weight, limited
evidence of male reproductive effects, and conflicting reports of reproductive outcomes in male
offspring, particularly in studies of DE (Section 7.4.2). Toxicological studies also reported effects for
several development outcomes, including immunological effects (placental and  related to asthma),
neurodevelopmental and behavioral effects (Section 7.4.2).
      In summary evidence is accumulating from epidemiologic studies for effects on low birth
weight and infant mortality, especially due to respiratory causes during the post-neonatal period. The
mean PM25 concentrations during the study periods ranged from 5.3-27.4 (ig/m3. Exposure to PM25
was usually associated with greater reductions in birth weight than exposure to PMi0. Several U.S.
studies of PMio investigating fetal growth reported  11-g decrements in birth weight associated with
PMio exposure. Most of these studies were conducted in California, where PM25 and PMi0_2.5
contribute almost equally to the PMio mass concentration.  So while these results can not be
attributed to one size fraction or the other, the consistency of the results strengthens the interpretation
that particle exposure may be causally related to reductions  in birth weight. Similarly, animal
evidence supported an association between PM2 5 and PMio exposure and adverse reproductive and
developmental outcomes, but provided little mechanistic information or biological plausibility for an
association between long-term PM exposure and adverse birth outcomes, including low birth weight,
or infant mortality. Epidemiologic studies do not consistently report associations between PM
exposure and preterm birth, growth restriction, birth defects or decreased sperm quality. New
evidence from animal toxicological studies on heritable mutations is of great interest, and warrants
further investigation. Overall, the epidemiologic  and toxicological evidence is SUQQBStiVB Of 3
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causal relationship between long-term exposures to PM25 and reproductive and
developmental outcomes.


7.4.3.2.  PM10.2.5
     Evidence is inadequate to determine if a causal relationship exists between long-
term exposure to PMi0-2.5 and developmental and reproductive outcomes because studies
have not been conducted in sufficient quantity or quality to draw any conclusion. A single study
found an association between PMi0_2.5 and birthweight (-13 g [95% CI: -18.3 to -7.6] per 10 ug/m3
increase), but no such association for PM2.5 (Parker et al., 2008, 156013).
7.4.3.3.  UFPs

     The 2004 PM AQCD did not report long-term exposure studies for UFPs. No epidemiologic or
animal toxicology studies have been conducted to evaluate the effects of long-term UFP exposure
and reproductive and developmental effects. Ambient air exposures, which likely include UFPs, are
reported in this ISA but there is no delineation of the separate contribution from UFPs. The evidence
is inadequate to determine if a causal  relationship exists between  long-term UFP
exposures and reproductive and developmental effects



7.5.  Cancer, Mutagenicity, and Genotoxicity

     Evidence from epidemiologic and animal toxicological studies has been accumulating for
more than three decades regarding the mutagenicity and carcinogenicity of PM in the ambient air.
DE has been identified as one source of PM in ambient air, and has been extensively studied for its
carcinogenic potential. In 1989, the International Agency for Research on Cancer (IARC) found that
there was sufficient evidence that extracts of DE particles were carcinogenic in experimental animals
and that there was limited evidence for the carcinogenic effect of DE in humans (IARC, 1989,
002958). This conclusion was based on studies in which organic extracts of DE particles were used
to evaluate the  effects of concentrates of the organic compounds associated with carbonaceous soot
particles. These extracts were applied to the skin or administered by IT instillation or intrapulmonary
implantation to mice, rats, or Syrian hamsters and an excess of tumors on the skin, lung or at the site
of injection were observed.
     In 2002, the U.S. EPA reviewed over 30 epidemiologic studies that investigated the potential
carcinogenicity of DE. These studies, on average, found that long-term occupational exposures to
DE were associated with a 40% increase in the relative risk of lung cancer (U.S. EPA, 2002,
042866). In the same report the U.S. EPA concluded that extensive studies with salmonella had
unequivocally demonstrated mutagenic activity in both particulate and gaseous fractions of DE.
They further concluded that DE may present a lung cancer hazard to humans (U.S. EPA, 2002,
042866). The particulate phase appeared to have the greatest contribution to the carcinogenic effect.
Both the particle core and the associated organic compounds demonstrated carcinogenic properties,
although a role for the gas-phase components of DE could not be ruled out. Almost the entire diesel
particle mass is < 10 um in diameter (PMi0), with approximately 94% of the mass of these particles
<2.5 um in diameter (PM2.5), including a subgroup with a large number of UFPs (U.S. EPA, 2002,
042866). U.S. EPA considered the weight of evidence for potential human  carcinogenicity for DE to
be strong, even though inferences were involved in the overall assessment, and concluded that DE is
"likely to be carcinogenic to humans by inhalation" and that this hazard  applies to environmental
exposures (U.S. EPA, 2002, 042866).
     Two recent reviews of the mutagenicity (Claxton et al., 2004, 089008) and carcinogenicity
(Claxton  and Woodall, 2007,  180391)  of ambient air have characterized the animal toxicological
literature on ambient air pollution and cancer. The majority of these toxicological studies have been
conducted using IT instillation or dermal routes of exposure.  Generally, the toxicological evidence
reviewed in this ISA has been limited to inhalation studies conducted with lower concentrations of
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PM (<2 mg/m3), relevant to current ambient concentrations and the current regulatory standard
(Section 1.3). Because this ISA focuses on toxicological studies which use the inhalation route of
exposure, it is possible that important evidence for the role of PM in mutagenicity, tumorigenicity,
and/or carcinogenicity may be missed. In order to accurately characterize the relationship between
PM and cancer and be consistent with the EPA Guidelines for Carcinogen Risk Assessment
(U.S. EPA, 2005, 086237). these reviews (that include studies that employ IT instillation and dermal
routes of exposure) are summarized briefly.
      Claxton et al. (2004, 089008) reviewed the mutagenicity of air in the Salmonella (Ames)
assay, and showed that hundreds of compounds identified in ambient air from varying chemical
classes are mutagenic and that the commonly monitored PAHs could not account for the majority of
mutagenicity associated with most airborne particles. They concluded that the smallest particles have
the highest toxicity per particulate mass, with the PM2.5 size fraction having greater mutagenic and
cytotoxic potential than the PM10 size fraction, which had a higher mutagenic potential than the TSP
size fraction. One study reviewed by Claxton et al. (2004, 089008) found that the cytotoxic potential
of PM2.s was higher in wintertime samples than in summertime samples. A series of studies on
source apportionment for ambient particle mutagenic activity reviewed by Claxton et al. (2004,
089008) indicate that mobile sources (cars and diesel trucks) account for most of the mutagenic
activity.
      Claxton and Woodall (2007, 180391) reviewed many studies that examined the rodent
carcinogenicity of extracts of ambient PM samples; the PM was of various size classes, often from
TSP samples. Among a variety of mouse and rat strains, application methods, and samples
employed, the authors found no  pattern that would suggest the routine use of a particular strain or
protocol would be more informative than another. The primary conclusion that comes from the
analysis of rodent carcinogenicity studies is that the most polluted urban air samples tested to date
are carcinogenic; the  contribution of PM and different size classes of PM to the carcinogenic effects
of ambient air has not been delineated. The differences in response by the various strains of inbred
mice indicate that the genetic background of an individual can influence tumorigenic response.
Studies examining different components of ambient PM (e.g., PAHs) confirm that ambient air
contains multiple carcinogens, and that the carcinogenic potential of particles from different airsheds
can be quite different. Therefore, one would expect the incidence of cancers related to ambient air
exposure in different  metropolitan areas to differ.
      Numerous epidemiologic  and animal toxicological studies of ambient PM and their
contributing sources have been conducted to assess the relative mutagenic or genotoxic potential.
Studies previously reviewed in the 2004 PM AQCD (U.S. EPA, 2004, 056905) provide evidence that
ambient PM as well as PM from specific combustion sources (e.g., fossil fuels) is mutagenic in vivo
and in vitro. Building on these results,  data from recent epidemiologic and animal toxicological
studies that evaluated the carcinogenic, mutagenic and/or genotoxic effects of PM, PM-constituents,
and combustion emission source particles are reviewed in this section.


7.5.1.  Epidemiologic Studies

      The 2004 PM AQCD reported on original and follow-up analyses for three prospective cohort
studies that examined the relationship between PM and lung cancer incidence and mortality. Based
on these findings, as well as on the results from case-control and ecologic studies, the 2004 PM
AQCD concluded that long-term PM exposure may increase the risk of lung cancer incidence and
mortality. The largest of the three prospective cohort studies included in the 2004 PM AQCD was the
ACS study (Pope et al., 2002, 024689). This study was the follow-up to the original ACS study
(Pope et al., 1995, 045159). and included a longer follow-up period and reported a statistically
significant association between PM2.5 exposure and lung cancer mortality.
      A 14- to 16-yr prospective study conducted using the Six Cities Study  cohort reported a
slightly  elevated risk  of lung cancer mortality for individuals living in the most polluted city (mean
PMi0: 46.5  (ig/m3; mean PM2.5 29.6 (ig/m3) as compared to the least polluted city (mean PMi0:
18.2 (ig/m3; mean PM25  11.0 (ig/m3) but the association was not statistically  significant (Dockery et
al., 1993. 0444571
      Re-analysis of the AHSMOG cohort, a study of non-smoking whites living in California,
concluded that elevated long-term exposure to PMi0 was associated with lung cancer incidence
among both men and women (Beeson et al.,  1998, 048890). The original study had reported an
excess of incident lung cancers only among women (Abbey et al., 1991, 042668). Further reanalysis
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of this cohort revealed an association between PM10 and lung cancer mortality among men but no
association among women (Abbey et al., 1999, 047559). In addition, McDonnell et al. (2000,
010319) reported increases in lung cancer mortality with long-term exposure to PM2.5 in the
AHSMOG cohort; no association was seen for PMi0_2.5.


7.5.1.1.   Lung Cancer Mortality and Incidence

      The following sections will examine  extensions of the above mentioned cohort studies and
new studies published since the 2004 PM AQCD. The section includes discussion of both lung
cancer incidence and mortality, as well as markers of exposure/susceptibility. A summary  of the
mean PM concentrations reported for the new studies is presented in Table 7-6. In addition, a
summary of the associations for lung cancer mortality and incidence are presented in Table 7-7 and
Figure 7-7 (Section 7.6) Further discussion of all-cause and cause-specific mortality is presented in
Section 7.6.
Table 7-6.    Characterization of ambient PM concentrations from recent studies of cancer and long-
            term exposures to PM.
Study
Brunekreef et al. (2009, 191947)
Bonneretal. (2005, 088993)
Jerret et al. (2005, 1894051
Laden et al. (2006, 0876051
Naess et al. (2007, 0907361
Palli et al. (2008, 1568371
Pedersen et al. (2006, 1568481
Sorensen et al. (2005, 0830531
Sram et al. (2007, 1884571
Sram et al. (2007, 1920841
Vineisetal. (2006, 1920891
Vinzents et al. (2005, 0874821
Location
The Netherlands
Wfestern NY State
Los Angeles, California
6 U.S. cities
Oslo, Norway
Florence, Italy
Czech Republic
Copenhagen, Denmark
Czech Republic
Czech Republic
Multi-city, Europe
Copenhagen, Denmark
Pollutant
PM25
TSP
PM25
PM25
PM25
PM10
PM10
PM25
PM10
PM25
PM10
PM25
PM10
PM25
PM10
PM10
Mean Annual
Concentration (ug/m '
28.3
44

Range of means across sites: 10.2-29.0
Avg of means across sites: 16.4
15
19
NR


Range of means across sites: 12.6-20.7
Avg of means across sites: 16.7


Range of means across sites: 36.4-55.6
Avg of means across sites: 46.0
Range of means across sites: 24.8-44.4
Avg of means across sites: 34.6
Range of means across sites: 19.9-73.4
Avg of means across sites: 35.4
Range of means across sites: 16.9-23.5
Avg of means across sites: 20.2
Upper Percentile
Concentrations (ug/m '
Max: 36.8

Max:27.1

Max: 22
Max: 30

Max: 46-120
Max: 120-238.6
75th: 24.3-27.7
Max: 55
Max: 38




      A subset of the ACS cohort study from 1982 to 2000 that included only residents of Los
Angeles, California was used to examine the association between PM2.5 and lung cancer mortality
while adjusting for both individual and neighborhood covariates (Jerrett et al., 2005, 189405). There
was a positive association between PM2.5 and lung cancer mortality when adjusting for 44 individual
covariates (RR 1.44 [95% CI:  0.98-2.11]  per 10 (ig/m3 increase in PM2.5). However, including all
potential individual and neighborhood covariates associated with mortality reduced the association
December 2009
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(RR 1.20 [95% CI: 0.79-1.82] per 10 ug/m3 increase in PM2.5). A recent re-analysis of the full ACS
cohort also demonstrated a positive association between PM25 and lung cancer mortality (RR 1.11
[95% CI: 1.04-1.18]) (Krewski et al., 2009, 191193). The authors observed modification of this risk
by educational attainment, with those completing a high school degree or less having greater risk. In
addition to utilizing the ACS cohort for a nationwide analysis, this same study conducted two
regional assessments, one in the New York City area and the other in the Los Angeles area. No
association was detected between PM25 and lung cancer mortality in the analysis of the region
included in the New York City analysis. A positive association was observed in the Los Angeles-area
analysis using an unadjusted model, but this association did not persist after control for individual,
ecologic, and copollutant covariates.
      The Six Cities Study was extended to include data from 1990-1998, a period including 1,368
deaths and 54,735 person-years (Laden et al., 2006,  087605). An elevated risk ratio for lung cancer
mortality was reported when the entire follow-up period (1974-1998) was included in the analysis
(RR 1.27 [95% CI 0.96-1.69] per 10 ug/m3 increase in average annual PM2.5). However, estimated
decreases in PM2.5 were not associated with reduced lung cancer mortality (RR 1.06 (95% CI:
0.43-2.62] for every 10 ug/m3 reduction in PM25).
      Naess et al. (2007, 090736) studied individuals aged 51-90 yr living in Oslo, Norway in 1992.
Death certificate data were obtained for 1992-1998 and information on PM was collected from
1992-1995. Women had a larger association of lung cancer mortality with PM25 compared to men.
Similar results were reported for PMi0.
      Most recently, Brunekreef et al. (2009,  191947) used the Netherlands cohort study (NLCS) on
diet and cancer to conduct a re-analysis of the research performed by Beelen et al. (2008, 156263)
examining the association between PM and both lung cancer mortality and incidence. After 10 yr of
follow-up, there was no association between PM25 and lung cancer mortality for either the analysis
of the full cohort (n = 105,296) (RR 1.06 [95% CI: 0.82-1.38] per 10 ug/m3 increase in PM25) or the
case-cohort (n = 4,075) (RR 0.87 [95% CI: 0.52-1.47]). There was also no association with black
smoke or traffic density variables, although living near a major roadway was associated with an
elevated relative risk for lung cancer in the full cohort analysis (RR 1.20 [95% CI: 0.98-1.47]). The
association was not present  in the case-cohort analysis (RR  1.07 [95% CI: 0.70-1.64]).
      In addition to lung cancer mortality, Brunekreef et al.  (2009, 191947) also examined the
association with lung cancer incidence using 11.3 yr of follow-up data. In both the full cohort and
the case-cohort analyses no  association was reported between PM2 5 and lung cancer incidence (full
cohort: RR0.81 [95% CI: 0.63-1.04]; case-cohort: RR0.67  [95% CI: 0.41-1.10] per 10 ug/m3
increase in PM2s). The  same was true for analyses of BS and traffic density variables.
      The association between PM  and incident lung cancers was examined in the European
Prospective Investigation into Cancer and Nutrition study (EPIC) (Vineis et al., 2006, 192089).
Within this cohort,  a nested  case-control study, the GenAir study, included cases of incident cancer
and controls matched on age, gender, smoking status, country of recruitment,  and time between
recruitment and diagnosis. Only non-smokers and former smokers who had quit smoking at least
10 yr prior were included. The study included 113 cases and 312 controls. No association was seen
between PMi0 and lung cancer (OR 0.91 [95% CI: 0.70-1.18] per 10 ug/m3). The OR was elevated
when cotinine, a marker for cigarette exposure, was included in the model but the authors state that
this is probably due to small study size (OR 2.85 [95% CI: 0.97-8.33] comparing > 11 ug/m3 to
<11 ug/m3). Control for other potential confounders, such as BMI, education level, and intake of
fruit and vegetables, did not have a  large impact on the estimate.
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Table 7-7.      Associations* between ambient PM concentrations from select studies of lung cancer
                  mortality and incidence.
Study
Cohort
Location
Years
Analysis subgroup
Effect Estimate (95% Cl)
MORTALITY -PM^
Dockeryetal. (1993, 044457)'
Krewski et al. (2000, 012281)'
Laden et al. (2006, 087605)
Beelen et al. (2008, 156263)
Beelen et al. (2008, 156263)
Brunekreef et al. (2009, 191947)
Brunekreef et al. (2009, 191947)
Pope etal. (1995,045159)'
Pope et al. (2002, 024689)'
Jerret et al. (2005, 189405)
Krewski et al. (2009, 191193)
Krewski et al. (2009, 191193)
Krewski et al. (2009, 191193)
McDonnell et al. (2000, 010319)'
Naess et al. (2007, 090736)
Naess et al. (2007, 090736)
Naess et al. (2007, 090736)
Naess et al. (2007, 090736)
Six-Cities
Six-Cities-Re-analysis
Six-Cities
NLCS
NLCS
NLCS-Re-analysis
NLCS-Re-analysis
ACS
ACS
ACS-LA
ACS-Re-analysis
ACS-Re-analysis
ACS-Re-analysis
AHSMOG




Six cities across the U.S.
Six cities across the U.S.
Six cities across the U.S.
Netherlands
Netherlands
Netherlands
Netherlands
U.S.
U.S.
Los Angeles
U.S.
New York City
Los Angeles
California
Oslo, Norway
Oslo, Norway
Oslo, Norway
Oslo, Norway
1974-1991
1974-1991
1974-1998
1987-1996
1987-1996
1987-1996
1987-1996
1982-1989
1982-2000
1982-2000
1982-2000
1982-2000
1982-2000
1973-1977
1992-1998
1992-1998
1992-1998
1992-1998



Full Cohort
Case Cohort
Full Cohort
Case Cohort


Intra-metro Los Angeles

Intra-metro New York City
Intra-metro Los Angeles
Men
Men, 51-70yrs
Men, 71-90yrs
V\fomen, 51-70yrs
Wfomen, 71-90yrs
1.18(0.89-1.57)
1.16(0.86-1.23)
1.27(0.96-1.69)
1.06(0.82-1.38)
0.87(0.52-1.47)
1.06(0.82-1.38)
0.87(0.52-1.47)
1.01 (0.91-1.12)
1.13(1.04-1.22)
1.44(0.98-2.11)
1.11 (1.04-1.18)
0.90 (0.29-2.78)
1.31 (0.90-1.92)
1.39(0.79-2.46)
1.18(0.93-1.52)
1.18(0.93-1.52)
1.83(1.36-2.47)
1.45(1.05-2.02)
MORTALITY- PMio
McDonnell et al. (2000, 010319)'
Naess et al. (2007, 090736) '
Naess et al. (2007, 090736)
Naess et al. (2007, 090736) '
Naess et al. (2007, 090736) '
AHSMOG




California
Oslo, Norway
Oslo, Norway
Oslo, Norway
Oslo, Norway
1973-1977
1992-1998
1992-1998
1992-1998
1992-1998
Men
Men, 51-70yrs
Men, 71-90yrs
V\fomen, 51-70yrs
Wfomen, 71-90yrs
1.23(0.84-1.80)
1.12(0.95-1.33)
1.14(0.97-1.36)
1.50(1.23-1.84)
1.29(1.03-1.60)
INCIDENCE - PM2.S
Beelen et al. (2008, 155681)
Beelen et al. (2008, 155681)
Brunekreef et al. (2009, 191947)
Brunekreef et al. (2009, 191947)
NLCS
NLCS
NLCS-Re-analysis
NLCS-Re-analysis
Netherlands
Netherlands
Netherlands
Netherlands
1987-1996
1987-1996
1987-1996
1987-1996
Full Cohort
Case Cohort
Full Cohort
Case Cohort
0.81 (0.63-1.04)
0.65(0.41-1.04)
0.81 (0.63-1.04)
0.67(0.41-1.10)
INCIDENCE -PMio
Beesonetal. (1998, 048890)
Vineis etal. (2006, 192089)
AHSMOG
GenAir
California
Europe
1977-1992
1993-1999
Men
Case-Control
1.99(1.32-3.00)
0.91 (0.70-1.18)
*per 10ug/m increase
fResults from the paper were standardized to10 ug/m3 [For McDonnell et al. (2000, 010319) the non-standardized results were reported based on IQR increments (24.3 ug/m3 for PM25 and 29.5 ug/m3 for
PM10). For Naess et al. (2007, 090736) the original hazard ratios were calculated based on quartiles of PM exposure. The results were converted to10 ug/m3 using the mean range of the four quartiles (3.95
ug/m3for PM25 and 5.88 ug/m3for PM10)].
    y was included in the 2004 PM AQCD
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7.5.1.2.   Other Cancers

      Bonner et al. (2005, 088993) conducted a population-based, case-control study of the
association between ambient exposure to PAHs in early life and breast cancer incidence among
women living in Erie and Niagara counties in the state of New York. Cases (n = 1,166 of which 841
were post-menopausal) were women with primary breast cancer, and controls (n = 2,105 of which
1,495 were post-menopausal) were frequency matched to the cases by age, race, and county of
residence. TSP was used as a proxy for PAH exposure. Annual average TSP concentrations
(1959-1997) were obtained from the New York State Department of Environmental Conservation for
Erie and Niagara Counties. Among postmenopausal women, exposure to high concentrations of TSP
(>140 (ig/m3) at birth was associated with an OR of 2.42 for breast cancer (95% CI: 0.97-6.09)
relative to low concentrations of TSP (<84 (ig/m3). ORs were elevated for pollution exposures at age
of menarche (OR: 1.45 [95% CI: 0.74-2.87]) and age at first birth (OR: 1.33  [95% CI: 0.87-2.06])
among postmenopausal women. Among premenopausal women, exposure to high concentrations of
TSP at birth was associated with an OR for breast cancer incidence of 1.79 (95% CI: 0.62-5.10)
relative to low exposure levels, exposure at age of menarche was associated with an OR of 0.66
(95% CI: 0.38-1.16), and exposure at age of first birth was associated with an OR of 0.52 (95% CI:
0.22-1.20).


7.5.1.3.   Markers of Exposure or Susceptibility

      Several studies looked at markers of exposure or susceptibility as the outcome associated with
short-term exposure. These studies are included here because they may be relevant to the mechanism
that leads to cancer associated with long-term exposures. For example, inflammation can contribute
to carcinogenesis by inducing genomic instability, which can then lead to altered gene expression,
enhanced proliferation, and resistance to apoptotic signals. Reactive oxygen and nitrogen species,
provided by PM components or inflammation pathways, can cause molecular damage leading to
cellular transformation. Elevated inflammatory cytokines, chemokines, and prostaglandins promote
tumor growth and angiogenesis, which in turn promotes metastasis and malignant invasion. In
particular, IL-6, IL-8, IL-lp, COX-2, and TNF-a have been implicated in these processes (Kundu
and Surh, 2008, 198840). Several lines of evidence support the involvement of COX-2 in the
pathogenesis of lung cancer (Lee et al., 2008, 198811). Both short- and long-term exposure studies
demonstrate relationships between various forms of PM and increased production of these
inflammatory mediators, both in the lungs and circulation. Additionally, limited evidence suggests
that exposure to PM (Chen and Schwartz, 2008, 190106). or traffic (Williams et al., 2009, 191945).
or residence in a polluted airshed (Calderon-Garciduenas et al., 2007, 091252; Calderon-
Garciduefias et al., 2009, 192107) are associated with decreases in the number or function of natural
killer cells or other white blood cells, indicating  suppression of anti-tumor defenses.
      A study performed in the Czech Republic compared 53 male policemen working at least
8 hours per day outdoors in urban air with age- and sex-matched controls who spent at least 90% of
their day indoors (n = 52) (Sram et al., 2007, 188457). During the sampling period, two monitors
from downtown and suburban areas detected levels of air pollutants in the following ranges: PMi0
32-55 (ig/m3, PM2.5 27-38 (ig/m3, c-PAHs 18-22  ng/m3, and B[a]P 2.5-3.1 ng/m3 using a VAPS
monitor (measurements taken with a HiVol monitor, which has a lower flow rate, had a mean for
PMio of 62.6 (ig/m3). c-PAHs detected on personal monitors during sampling days had a mean  of
12.04 ng/m3 among the policemen and 6.17 ng/m3 among the controls. No difference in percent of
chromosomal aberrations was observed between the policemen and control group using conventional
cytogenetic analysis. However, using fluorescent in situ hybridization (FISH), a difference in
chromosomal aberrations between the policemen and control group was reported. For example, the
percentage of aberrant cells, as well as the genomic  frequency of translocations per 100 cells, was
about 1.4-fold greater in the policemen. This was largely driven by a difference in chromosomal
aberrations between nonsmoking policemen and nonsmoking controls. A similar study that included
only the policemen (n = 60), reported that the mean exposure to c-PAHs and  B[a]P for 40-50 days
before sampling was associated with chromosomal aberrations when analyzed with FISH (Sram et
al., 2007, 192084). However, when included in a model with other covariates, the association with
these variables was null. No association was present with use of conventional cytogenetic analysis.
      Palli et al. (2008, 156837) investigated the correlation between ambient PMi0 concentrations
and individual levels of DNA bulky  adducts. Study participants were 214 healthy adults aged
December 2009                                  7-73

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35-64 yr at enrollment who resided in the city of Florence, Italy. This study was conducted between
1993 and 1998. PMi0 exposure levels were based on daily environmental measures provided by two
types of urban monitoring stations (high-traffic and low-traffic). The researchers assessed correlation
between DNA bulky adducts measured in blood samples and PMi0 concentrations prior to blood
sample collection. Time windows of PMi0 exposure evaluated in this study were 0-5 days, 0-10 days,
0-15 days, 0-30 days, 0-60 days, and 0-90 days prior to blood sample collection. Overall, average
PMio concentrations decreased during the study period, with some fluctuations. Quantitative values
were not reported, but PMi0 appeared to range between approximately 30 and 100 (ig/m3 for high-
traffic stations, and between approximately 20 and 50 (ig/m3for low-traffic stations. This study
found that levels  of DNA bulky adducts among non-smoking workers with occupational traffic
exposure were positively correlated with cumulative PMi0 levels from high-traffic stations during
approximately 2 wk preceding blood sample collection (0-5 days:  r = 0.55, p = 0.03; 0-10 days:
r = 0.58, p = 0.02; 0-15 days: r = 0.56, p = 0.02). DNA bulky adducts were not associated with PMi0
levels among Florence residents with no occupational exposure to vehicle emissions or among
smokers. DNA bulky adducts were not  associated with PMi0 levels assessed by low-traffic urban
monitoring stations.
      The association between personal exposure to water-soluble transition metals in PM2.5 and
oxidative stress-induced DNA damage was investigated among 49 students from Central
Copenhagen, Denmark (Sorensen et al., 2005, 083053).  Researchers assessed PM2.5 exposure by
personal sampling over two weekday periods twice in one year (November 1999 and August 2000),
and determined the concentration of water-soluble transition metals (V, Cr, Fe, Ni, Cu and Pt) in
these samples. In addition, lymphocyte and 24-h urine samples were analyzed for DNA damage by
measuring 7-hydro-8-oxo-2'-deoxyguanosine (8-oxodG). Mean concentrations and corresponding
IQR of these metals differed between months of sample collection. This study found that 8-oxodG
concentration in lymphocytes was significantly associated with V  and Cr concentrations, with a
1.9% increase in  8-oxodG per 1 (ig/L increase in V concentration and a 2.2% increase in 8-oxodG
per 1 (ig/L increase in Cr concentration; these associations were independent of the PM2.5 mass
concentration. The other transition metals were not significantly associated with the 8-oxodG
concentration in lymphocytes, and none of the six measured transition metals was associated with
the 8-oxodG concentration in urine.
      Vinzents et al. (2005, 087482) investigated the association between UFP and PM10
concentrations with levels of purine oxidation and strand breaks in DNA using a crossover design in
Copenhagen, Denmark. Study participants were 15  healthy nonsmoking individuals with a mean age
of 25 yr. UFP exposure was evaluated using number concentration obtained in the breathing zone by
portable instruments in six 18-h weekday periods from March to June 2003. Ambient concentrations
for PMio and UFP were also measured on all exposure days at curbside street stations and at one
urban background station. Oxidative DNA damage  was assessed by evaluating strand breaks and
oxidized purines  in mononuclear cells isolated from venous blood the morning after exposure
measurement. Mean number concentration of UFPs (street station) was 30.4xl03 UFPs/mL (standard
deviation [SD]: 1.38), mean mass concentration of PMi0at a background monitoring station was
16.9 (ig/m (SD:  1.53), and mean mass  concentration of PMio at a street station was 23.5 (ig/m3 (SD:
1.48). Mean personal exposure to UFPs was  32.4xl03 UFPs/mL (SD: 1.49) while bicycling (5
occasions), 19.6xl03 UFPs/mL (SD:  1.78) during other outdoor activities (6 occasions),  and
13.4><103 UFPs/mL (SD:  1.96) while indoors (6 occasions). The regression coefficients of the mixed-
effects models looking at level of purine oxidation were estimated as 1.50><10~3 (95% CI: 0.59xlO~3
to  2.42xlO~3;/> = 0.002) for cumulative outdoor exposure and 1.07xlO~3 (95% CI: 0.37xlO~3 to
1.77xlO~3;/? = 0.003) for cumulative indoor  exposure. Neither cumulative outdoor nor cumulative
indoor exposures to UFPs were associated with strand breaks. Neither ambient air concentrations of
PMio nor number concentrations of UFPs at monitoring stations were significant predictors of DNA
damage.
      Additionally, a number of studies employed ecologic study designs, comparing the prevalence
of biomarkers in  populations from more polluted locations to those in less polluted locations. In a
pilot study conducted in the Czech Republic  (Pedersen et al., 2006, 156848). children age 5-11 yr
provided 5 mL blood samples and the frequency of micronuclei (MN) in peripheral blood
lymphocytes was analyzed as a measure of cytogenetic effects. Significantly higher frequencies of
MN were found in younger children living in Teplice (PM2.5 concentration =120 (ig/m3) than in
Prachatice (PM? 5 concentration = 46 (ig/m3). The levels of c-PAHs were also much higher in Teplice
(nearly 30 ng/m  in Teplice and about 15 ng/m3 in Prachatice). The difference in MN frequencies
December 2009                                 7-74

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observed in the children from the two locations may be attributable to differences in exposure to air
pollution, but could also be due to differences in diet or other environmental exposures. This finding
is noteworthy considering MN formation in peripheral blood lymphocytes is thought to be
biologically relevant for carcinogenesis.
      Avogbe et al. (2005, 087811) showed a correlation between the level of oxidative DNA
damage in individuals and exposure to ambient UFPs. Formamidopyrimidine DNA glycosylase
sensitive sites and the presence of DNA strand breaks were assessed in blood and urine samples
obtained from healthy, non-smoking male volunteers that lived and worked in different areas of
Cotonou, Benin. Exposure to benzene was assessed by urinary excretion of S-phenylmercapturic
acid. There was a high degree of correlation between exposure to benzene and UFPs and the
presence of DNA strand breaks and formamidopyrimidine DNA glycosylase sensitive sites (rural
subjects < suburban subjects < residents living near high traffic roads < taxi drivers). Genotyping
studies showed that the magnitude of the effects of benzene and UFPs may be modified by
polymorphisms in GSTP1 andNQOl genes.
      Tovalin et al. (2006, 091322) evaluated the association between exposure to air pollutants and
the level of DNA damage using the single cell gel electrophoresis (comet) assay. Mononuclear
lymphocytes from outdoor and indoor workers from two areas in Mexico, Mexico City (large city)
and Puebla (medium size city), were  evaluated. The  outcomes showed that the outdoor workers in
Mexico City exhibited greater DNA damage than indoor workers in the same region. Similar levels
of DNA damage were observed between indoor and  outdoor workers in Puebla. The level of
observed DNA damage was correlated with exposure to O3 and PM2.5.
      In summary, several recent studies have reported an association between  lung cancer mortality
and long-term PM2.5 exposure. Although many of the estimates include the null in the confidence
interval, overall the results have shown a positive relationship. The two recent studies that looked at
lung cancer incidence did not report an association with PM2.5 (Brunekreef et al., 2009, 191947) or
PMio (Vineis et al., 2006,  192089). Studies of exposure/susceptibility markers have reported
inconsistent outcomes, with some markers being associated with PM and others not.


7.5.2.  lexicological Studies

      Over the past 30 yr numerous mutagenicity and genotoxicity studies of ambient PM and their
contributing sources have been conducted to assess the relative mutagenic or genotoxic potential.
Studies previously reviewed in the 2004 PM AQCD  (U.S. EPA, 2004, 056905)  provide compelling
evidence that ambient PM and PM from specific combustion sources (e.g., fossil fuels) are
mutagenic in vivo and in vitro. Research cited in the 2004 AQCD demonstrated mutagenic activity
of ambient PM from urban centers in California, Germany and the Netherlands. These studies
suggested that ubiquitous  emission sources, particularly motor vehicle emissions, rather than isolated
point sources were largely responsible for the mutagenic effects. In addition, the mutagenicity was
dependent upon the chemical composition of the PM with unsubstituted poly aromatic compounds
and semi-polar compounds being highly mutagenic.  Mutagenicity was also dependent on size, with
the fine fraction of urban PM having greater effects than the coarse fraction. Genotoxic activity was
demonstrated for ambient PM from two high traffic areas (one upwind and one downwind) and a
rural site. In addition, the 2004 AQCD reported that  exhausts from gasoline and diesel engines were
mutagenic and that DE was more potent. More mutagenicity was observed for exhaust from cold
starts than starts at room temperature. Both gaseous and particulate fractions of DE were found to be
mutagenic. Sequential fractionation of extracts from gasoline and DE implicated the polar fractions,
especially nitrated polynuclear aromatic compounds, as contributing  greatly to  mutagenicity. Among
some of the other mutagenically active  compounds found in the gas phase of DE are ethylene,
benzene, 1,3-butadiene, acrolein and several PAHs, all of which are also present in gasoline exhaust.
Also cited in the 2004 AQCD were studies demonstrating mutagenic effects of emissions from
wood/biomass burning, which were primarily attributable to the organic fraction and not the
condensate. It was noted that wood smoke induced both frameshift mutations and base pair
substitution but not DNA adducts. Further, emissions from coal combustion in China were found to
be mutagenic, with both polar and aromatic fractions contributing to  effects. Little data were
available on the mutagenicity of coal fly ash emissions from U.S. conventional combustion plants. In
conclusion, these studies provide evidence that ambient PM and combustion-derived PM are
mutagenic/genotoxic. The 2004 AQCD noted that there is not a simple relationship between
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mutagenic potential and carcinogenic potential in animals or humans. No studies evaluating
carcinogenic effects of PM were reported in the 2004 AQCD.
      Building on results of earlier studies in the 2004 PM AQCD, data from newly published
studies that evaluated the mutagenic, genotoxic and carcinogenic effects of PM, PM-constituents,
and combustion emission source particles are reviewed. Pertinent studies are described briefly in the
following paragraphs. A summary table is provided in Annex D, Tables D7 and D8).


7.5.2.1.   Mutagenesis and Genotoxicity



      In Vitro Studies

      In general, studies have focused on PM and PM extracts for mutagenicity testing using
bacteria and mammalian cell lines. PM and/or PM extracts from ambient air samples, wood smoke,
and coal, diesel, or gasoline combustion have all been reported to induce mutation in S. typhimurium
and in cultured human cells (Abou et al, 2007, 098819: Gabelova et al, 2007, 156457: Gabelova et
al., 2007, 156458: Hannigan et al., 1997, 083598: Hornberg et al., 1998, 155849). In addition, effects
associated with PM and PM-associated constituents include induction of MN formation, DNA
adduct formation, SCE, DNA strand breaks, frameshifts and inhibition of gap-junction intercellular
communication (Alink et al., 1998, 087159: Arlt et al., 2007, 097257: Avogbe et al., 2005, 087811:
Gabelova et al., 2007,  156457: Gabelova et al., 2007, 156458: Healey et al., 2006, 156532: Hornberg
et al., 1996, 087164: Hornberg et al., 1998, 155849: Sevastyanova et al., 2007, 1569691
      Constituents adsorbed onto individual particles play a large role in the genotoxic potential of
PM. Poma et al. (2006, 096903) showed that fine CB particles were consistently less genotoxic than
similar concentrations of PM2.5 extracts, suggesting that the adsorbed components play a role in the
genotoxic potential of PM. Total PAH and carcinogenic PAH content were correlated with the
genotoxic effects of PM (De Kok et al., 2005, 088656: Sevastyanova et al., 2007, 156969).
Comparison of different extracts (water-soluble versus organic) by Gutierrez-Castillo et al. (2006,
089030) indicated that water-soluble extracts were more genotoxic than the corresponding organic
extracts. Sharma et al.  (2007, 156975) reported that mutagenic activity of extracted PM samples
collected in and around a waste incineration plant was attributed to the moderately polar and polar
fractions. The polar and crude fractions were mutagenic without metabolic activation, suggesting a
direct mutagenic effect. No mutagenic activity was observed from any of the nonpolar samples
evaluated. Arlt and colleagues (2007, 097257) have shown that the PM constituents
2-nitrobenzanthrone (2-NB) and 3-nitrobenzanthrone were genotoxic in a variety of bacterial and
mammalian cell systems.
      Conflicting data have been reported on the role of metabolic enzymes in the genotoxicity of
PM and their adsorbed constituents. Arlt et al. (2007,  097257) reported that the PM constituent 2-NB
was genotoxic in bacterial and mammalian cells. However, metabolic activation with the human N-
acetyltransferase 2 or sulfotransferase (SULT1A1)  enzyme was needed for the effect to be observed
in human cells. Erdinger et al. (2005, 156423) demonstrated that mutagenic activity was not affected
when metabolism was induced, de Kok et al. (2005, 088656) evaluated the relationship between the
physical, chemical, and genotoxic effects of ambient PM. TSP, PMi0, and PM2.5 were sampled at
different locations and the extracts were assessed for mutagenicity and induction of DNA adducts in
cells.  Overall, induction of rat liver S9 metabolism generally reduced the mutagenic potential via the
Ames assay of the particle fractions and DNA reactivity (induction of DNA adducts) was generally
higher after metabolic activation. Binkova et al. (2003, 156274)  found that the addition of S9
increased PMio-dependent DNA adduct formation.

      Ambient Air

      A limited number of studies evaluated the impact of the season on the genotoxic effects of
ambient PM. A few studies have indicated that greater genotoxic effects were associated with
samples collected during the winter months compared to those collected in the summer (Abou et al.,
2007, 098819: Gabelova et al., 2007, 156457: Gabelova et al., 2007, 156458). In contrast, Hannigan
et al. (1997, 083598) indicated that no seasonal variation was observed. Studies have also  shown that
greater genotoxic effects were associated with smaller particle size extracts (e.g., PM2.5>PMi0) and
December 2009                                 7-76

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from samples collected in urban areas or closer to higher trafficked areas (Abou et al., 2007, 098819;
Hornberg et al., 1998, 155849).
      de Kok et al. (2005, 088656) found the direct mutagenicity (Ames assay) and the direct DNA
reactivity (DNA adduct formation) of the PM2.s size fraction was significantly higher than that of the
larger size fractions (TSP, PMi0) at most locations.
      DNA damage was assessed by the Comet assay in A549 cells exposed to PM collected from a
high traffic area in Copenhagen, Denmark (TSP approximately 30 ug/m3) and compared to the
results from exposure of A549 cells to standard reference materials (SRM1650 or SRM2975) at the
same concentrations (2.5-250 ug/ml) (Danielsen et al., 2008,  192092). All three particles induced
strand breaks and oxidized purines in a dose-dependent manner and there were no  obvious
differences in potency. In contrast, only the ambient PM formed 8-oxodG when incubated with calf
thymus DNA, which may be due to the concentration of transition metals.

      Diesel and Gasoline Exhaust

      Automobile DE particles (A-DE particles) was tested in S. typhimurium strains TA98, TA100,
and its derivatives (e.g., TA98NR and YG1021) and found to be more mutagenic than forklift DE
particles (f-DE particles, derivative SRM2975), based on PM mass. A-DE particles had 227 times
more PAH-type mutagenic activity and 8-45 times more nitroarene-type mutagenic activity
(DeMarini et al., 2004, 066329). Using a diesel engine without an oxidation catalytic converter
(OCC), the diesel engine exhaust particle extract produced the highest number of revertant colonies
in strains TA98 and TA100 with and without S9 at several tested loads when compared to extracts
from low-sulfur diesel fuel (LSDF), rapeseed oil methyl ester (RME), and soybean oil methyl ester
(SME). When an OCC was installed in the exhaust pipe of the engine, all extracts reduced the
number of revertant colonies in both strains with and without S9 at partial loads but increased the
number of revertant colonies without S9 at rated power. At idling, DE particles extracts increased the
number of revertant colonies with and without S9 (Bunger et al., 2006,  156303). In a separate study,
engine emissions (particle extracts and condensates) from rapeseed (canola) oil were found to
produce greater mutagenic effects in S typhimurium strains TA98 and TA100 than DE particles
(Bunger et al., 2007,  156304). Additionally, DE extract (DEE) from diesel fuel containing various
percentages of ethanol was also observed to induce mutational response in two Salmonella strains.
Base diesel fuel DEE and DEE from fuel with 20% ethanol caused more significant DNA damage in
rat fibrocytes L-929 cells than extracts containing 5, 10, or 15% ethanol (Song et al., 2007,  155306).
      DE and gasoline engine exhaust particles, as well as their semi-volatile organic compound
(SVOC) extracts,  induced mutations in the two S. typhimurium strains YG1024 and YG1029 in the
absence and presence of S9; the PM extracts were more mutagenic than the SVOC extracts.
Additionally, all extracts except the DE extract induced DNA damage and MN formation in Chinese
hamster lung V79 cells (Liu et al., 2005, 097019). Another study demonstrated that gasoline engine
exhaust significantly  increased colony formation in TA98 with and without S9 (Zhang et al., 2007,
157186).
      Jacobsen et al.  (2008, 156597) used the FEl-Muta™ Mouse lung epithelial cell line to
investigate  putative mechanisms of DE particle-induced mutagenicity. Mutation ion frequencies and
ROS were determined after cells were incubated with 37.5 or 75 ug/ml DE particles (SRM1650) for
72-h (n = 8). The mutation frequency at the 75 ug/ml dose was significantly increased (1.55-fold;
p<0.001) in contrast to cells treated with 37.5 ug/ml DE particles. DE particles-induced ROS
generation 1.6- to 1.9-fold in the epithelial cell cultures after 3 h of exposure compared with the 3- to
10-fold increase in ROS  production previously reported for CB. The  authors concluded that the
mutagenic activity of DE particles is likely attributable to activity from the organic fraction that both
contains reactive species and can generate ROS.
      In human A549 and CHO-K1 cells, the organic fraction of DE  particles significantly increased
the amount of Comet and MN formation, respectively, in the presence and absence of SKF-525A (a
CYP450 inhibitor) and S9, respectively (Oh and  Chung, 2006, 088296). The organic base and
neutral fractions of DE particles also significantly induced DNA damage but only without SKF-
525A, and all fractions but the moderately polar fraction (phthalates and PAH oxyderivatives)
induced MN formation with and without S9 (Bao et al., 2007, 097258). Gasoline engine exhaust
significantly induced DNA damage as measured in the Comet assay and increased the frequency of
MN in human A549 cells (Zhang et al., 2007, 157186). In human-hamster hybrid (AL) cells, DE
particles (SRM 2975) dose-dependently increased the mutation yield at the CD59 locus; this was
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significantly reduced by simultaneous treatment with phagocytosis inhibitors (Bao et al., 2007,
097258).

      Wood Smoke
      The mutagenicity of wood smoke and cigarette smoke (CS) extracts was assayed in
S. typhimurium strains TA98 and TA100 (Ames assay) using the pre-incubation assay with
exogenous metabolic activation (rat liver S-9). Extracts of both samples (62.5 or 125 (ig  total PM
equivalent/ml) were equally mutagenic to strain TA98 but the wood smoke extract was less
mutagenic than the CS extracts in strain TA100 (Iba et al., 2006, 156582).


      In Vivo studies
      Ambient Air

      The contribution of ambient urban roadside air exposure (4, 12, 24, 48 or 60 wk) to DNA
damage was examined in the lungs, nasal mucosa, and livers of adult male Wistar rats in Kawasaki,
Japan (Sato et al., 2003, 096615). Messenger RNA levels of CYP450 enzymes that catalyze the
transformation of PAHs to reactive metabolites were also evaluated. Concentrations of gases were
reported to be 12-182 ppb NO and 0-9 ppb NO2 in the filtered air chamber and 33-280 ppb NO and
42-81 ppb NO2 in the experimental group chamber.  Suspended PM concentrations were 11-19 (ig/m3
in the filtered air chamber and 42-100 (ig/m3 (average 63 (ig/m3) in the experimental group chamber.
Body weight significantly decreased in exposed animals at 24, 48 and 60 wk. A 4-wk exposure to
urban roadside air resulted in significant increases in multiple DNA adducts (lung, nasal, and liver
DNA adducts). With longer exposures, there were significant increases in lung (48 wk), nasal
(60 wk), and liver DNA adducts (60 wk). Changes were seen in CYP1A2 mRNA at 4 wk with a
2.3-fold increase in exposed animals compared to the control group with no change observed at
60 wk; CYP1A1  mRNA was unchanged. These results indicate that exposure to ambient air in this
roadside area could induce DNA adduct formation, which may be important for carcinogenicity.
Earlier studies (Ichinose et al., 1997, 053264) have shown that 8-oxodG, a DNA adduct, is elevated
along with tumor formation in a dose-dependent manner in mice administered DE particles. The
finding of adducts in the liver indicated that deposition of PM and its associated PAHs in the lung
can have indirect effects on extrapulmonary organs. It should be noted that PM deposition on the fur
and ingestion during grooming cannot be ruled out as a possible exposure route.
      Another animal toxicological study employed "non-carcinogenic" particles obtained from
pooled non-cancerous lung tissue collected during surgical lung resection from three non-smoking
male patients diagnosed with lung adenocarcinomas (Tokiwa et al., 2005, 191952). Particles were
partially purified to remove organic compounds. Morphologically the particles were similar to DE or
ambient air PM and the organic extracts from the particles were directly mutagenic in S.
typhimurium tester strains TA98, YG1021 and YG1024. BALB/c and ICR mice were intratracheally
instilled with particles at doses of 0.25, 0.5, 1.0, or 2.0 mg/mouse. After 24 h, 8-oxodG was
measured in lung DNA and found to be increased in ICR mice in a dose-dependent manner, reaching
a maximum of-2.75 8-oxodG/105 dG at the 2.0 mg dose. The response was statistically significant
at doses of 0.5, 1.0, and 2.0 mg. The increased 8-oxodG levels observed in  vivo was reported to be
likely due to hydroxyl radicals presumed to be involved in phagocytosis of non-mutagenic particles
by inflammatory cells that could induce hydroxylation of guanine residue on DNA.
      Diesel Exhaust

      An in vivo study employed gtp delta transgenic mice carrying the lambda EG 10 on each
Chromosome 17 from a C57BL/6J background to investigate the effects of DE particles on mutation
frequency (Hashimoto et al., 2007, 097261). Mice were exposed via inhalation to DE particles or via
IT instillation to DE particles or DE particle extract and lambda EG10 phages were rescued; E. coli
YG6020 was infected with the phage and screened for 6-thioguanine resistance. The mutagenic
potency (mutation frequency per mg) caused by DE particle extract was twice that of DE particles,
suggesting that the mutagenicity of DE particles is attributed primarily to compounds in the extract,
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since ~50% of the weight of DE particles was provided by the extract. There was no difference in
mutation frequency between the 1 and 3 mg/m DE particle groups after 12 wk of exposure.

      Wood Smoke

      One recent study measured the effect of freshly generated hardwood smoke on CYP1A1
activity based on ethoxyresorufin O-deethylase in pulmonary microsomes recovered from male
Sprague-Dawley rats exposed to hardwood smoke by nose-only inhalation exposure (Iba et al, 2006,
156582). CYP1A1 activity in rat lung explants treated with extracts of the total PM (TPM) from
hardwood smoke samples and from freshly generated cigarette smoke (CS) was also evaluated.
Unlike CS, hardwood smoke did not induce pulmonary CYP1A1 activity or mRNA (assessed by
northern blot analysis) nor did extracts of hardwood smoke TPM induce CYP1A1 protein (assessed
by western blot analysis) in cultured rat lung explants. The results suggest that unique constituents
that are activated by CYP1 Al may be present in CS but not hardwood smoke.


7.5.2.2.   Carcinogenesis

      Studies published prior to the 2004 AQCD that evaluated the carcinogenicity of ambient air
were reviewed by Claxton and Woodall (2007, 180391). Five studies involved chronic inhalation
exposures in rodents. No statistically significant increase in tumorigenesis was observed following
chronic exposure to urban air pollution in Los Angeles (Gardner, 1966, 015129; Gardner et al., 1969,
015130; Wayne  and Chambers, 1968, 038537). However in a study conducted in Brazil, urban air
pollution was found to enhance the formation of urethane-induced lung tumors in mice (Cury et al.,
2000, 192100; Reymao et al., 1997, 084653).
      Two recent studies evaluated the carcinogenic potential of chronic inhalation exposures to DE
(Reed et al., 2004, 055625) and hardwood smoke (Reed et al., 2006, 156043). Two  indicators of
carcinogenic potential, formation of MN and tumorigenesis were measured in strain A/J mice, which
is a mouse model that spontaneously develops lung tumors. Exposure to DE or hardwood smoke at
concentrations of 1,000  ug/m3 and below did not cause increased formation of MN  or an increased
rate of lung tumors in this cancer-prone rodent model. These studies are described below.


      Diesel  Exhaust

      A/J mice were exposed to 30, 100, 300 and 1000 ug/m3 DE for 6 h/day and 7 days/wk for
6 mo (Reed et al., 2004, 055625). The concentration of gases in this including NOX, NO2, CO, SO2,
NH3, methane, non-methane VOC, and FID total hydrocarbon ranged from control to high dose
group values of 0 to 50.4 ± 0.6 ppm, 0.2 ± 0.2 to 6.9 ± 3.3 ppm, 0.3 ± 0.1 to 30.9 ±  4.5 ppm, not
detectable to 955.2 ± 58.4 ppb, 176.5 ± 8.8 to 9.1 ± 0.2 ug/m3, 1406.5 ± 253.2 to 2642.1 ±
455.9 ug/m3, 134.0 ± 52.1 to 1578.6 ± 256.2 ug/m3, 0.1 ± 0.1 to 2.2 ± 0.2  ppm, respectively. Particle
sizes in the four exposure groups ranged from 0.10-0.15 urn MMAD with geometric standard
deviations of 1.4-1.8. Following the 6-mo exposure and a 6-mo recovery period, mice were collected
and MN formation in blood and tumor multiplicity and tumor incidence were measured in lungs. No
increases in formation of MN or numbers of lung adenomas were observed in DE-exposed mice
compared with controls.


      Wood Smoke

      A/J mice were exposed to 30, 100, 300 and 1,000 ug/m3 hardwood  smoke or to 30, 100, 300
and 1,000 ug/m3 DE for 6 h/day and 7 days/wk for 6 mo (Reed et al., 2006, 156043). Gaseous
components of the hardwood smoke included CO, NH3, and non-methane VOC with concentrations
from control levels to high dose hardwood smoke exposure ranging from 229 ± 31 to 14887.6 ±
832.3 ppm, 139.3 ± 2.3 to 54.9 ± 1.2 ug/m3 and 177.6 ± 10.4 to 3455.0 ± 557.2  ug/m3, respectively.
Concentrations of NOX, NO2and SO2were reported to be null. Particle sizes in the four exposure
groups ranged from 0.25-0.36 urn MMAD with geometric standard deviations of 2.0-3.3. Following
the 6-mo exposure and a 6-mo recovery period, mice were collected and MN formation in blood and
tumor multiplicity and tumor incidence were measured in lungs. No increases in formation of MN or
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numbers of lung adenomas were observed in hardwood smoke-exposed mice compared with
controls. However, hardwood smoke from this study was mutagenic in the Ames reverse mutation
assay.


7.5.2.3.   Summary of lexicological Studies

      In summary, numerous new in vitro studies confirm and extend findings reported in the 2004
AQCD that ambient PM from urban sites and combustion-derived PM are mutagenic and genotoxic.
A small number of new studies were conducted in vivo. One of these studies demonstrated increased
mutagenic potency in mice exposed to DE particles and DE particle extract. Another study found
increased formation of 8-oxodG, a DNA adduct, following IT instillation of PM in mice. A chronic
inhalation study of rats exposed to urban roadside air reported increased formation of DNA adducts
in nose, lung, and liver and induction of CYP1A2. Inhalation exposure of rats to hardwood smoke
failed to induce CYP1A1 in another study. Finally, two chronic inhalation studies found no evidence
of carcinogenic potential for DE and hardwood smoke in a cancer-prone mouse model. Collectively,
these results provide some evidence, mainly from in vitro studies, to support the biological
plausibility of ambient PM-lung cancer relationships observed in epidemiology studies.


7.5.3.  Epigenetic Studies and Other Heritable DNA mutations

      Two epidemiologic epigenetic studies examined the effect of PM on DNA methylation. Both
studies examined methylation of Alu and long interspersed nuclear element-1 (LINE-1) sequences,
which are located in repetitive elements. In previous studies, methylation of these sequences has
been linked to global genomic DNA methylation content (Weisenberger et al., 2005, 192101; Yang et
al., 2004, 192102).
      The first study included men age 55 and older who were part of the Normative Aging Study in
the Boston area (Baccarelli et al., 2009, 192155). A stationary monitoring site located 1 km from the
examination site was used to estimate ambient PM25 exposure for the duration of the study
(1999-2007). During the study period, the median level of PM25> averaged over 7-day periods, was
9.8 (ig/m3 (interquartile range 8.0-12.0 (ig/m3). There was no association between PM2 5 and Alu
methylation. LINE-1 methylation was associated with  PM2.5 measured over the 7 days before the
examinations.
      The second study included 63 healthy men aged 27-55 yr working at an electric furnace steel
plant (Tarantini et al., 2009, 192010). Blood samples were taken twice, once in the morning after
2 days of not working and once  in the morning after 3  full days of work. PMi0 was measured in
11 work areas and individuals completed daily logs about the amount of time spent in each area. On
average, individuals had an estimated exposure of 233.4 (ig/m3 PM10 (range 73.4-1220.2 (ig/m3).
Short-term exposure did not alter the methylation of Alu and LINE-1. To examine effects of long-
term exposure, both blood samples were considered independent of time, and Alu and LINE-1 were
examined with respect to overall estimated PMi0 exposure using mixed effects models. There was a
negative association between increasing levels of PMi0 exposure and Alu and LINE-1  methylation,
indicating that PMi0 causes epigenetic changes to occur with long-term exposure. This study also
looked at levels of iNOS gene, which is a gene suppressed by DNA methylation. iNOS expression
was not associated with long term exposure to PMi0 but was affected by methylation in the short
term.
      Animal toxicology studies evaluating the effect of PM exposure on changes in the epigenome
and other non-epigenetic heritable DNA changes have  only recently been conducted. After earlier
work showed increased germline mutation rates in herring gulls nesting near steel mills on Lake
Ontario (Yauk and Quinn, 1996, 089093) further work was conducted to address air-dependent
contribution to germline mutations by housing male and female Swiss Webster mice in the same area
and comparing mutation rates in those animals with mutation rates of animals housed in a rural
setting with less air pollution (Somers  et al., 2002, 078100). To determine if PM or the gaseous
phase of the urban air was responsible for heritable mutations, Yauk et al.  (2008, 157164) exposed
mature male C57BlxCBA Fl hybrid mice to either HEPA-filtered air or to ambient air in Hamilton,
Ontario, Canada for 3 or 10 wk, or 10 wk plus 6 wk of clean air exposure (16 wk) (also discussed in
Section 7.4.2.5). Sperm DNA was monitored for ESTR mutations, testicular sample bulky DNA
adducts, and DNA single or double strand breaks. In addition, male-germ line (spermatogonial stem
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cell) DNA methylation was monitored post-exposure. This area in Hamilton is near two steel mills
and a major highway. Air composition showed mean concentrations for TSP of 93.8 ± 17 (ig/m3,
PAH of 8.3 ±1.7 ng/m3, and metal of 3.6 ± 0.7 ug/m3. Mutation frequency at ESTR Ms6-hm locus in
sperm DNA from mice exposed 3 or 10 wk did not show elevated ESTR mutation frequencies, but
there was a significant increase in ESTR mutation frequency at 16 wk compared to  HEPA-filter
control animals, pointing to a PM-dependent mechanism of action. No detectable DNA adducts were
observed in testes samples at any of the time points monitored. To verify inhalation exposure to
particles, DNA adducts were reported in the lungs of mice exposed for 3 wk to ambient air; no other
time points showed detectable DNA adduct formation. Hypermethylation of germ-line DNA was
also observed in mice exposed to ambient air for 10 and 16 wk. These PM-dependent epigenetic
modifications (hypermetnylation) were not seen in the halploid stage (3 wk) of spermatogenesis, but
were nonetheless seen in early stages of spermatogenesis (10 wk) and remained significantly
elevated in mature sperm even after removal of the mouse from the environmental exposure (16 wk).
Thus, these studies indicate that the ambient PM phase and not the gaseous phase is responsible for
the increased frequency of heritable DNA mutations and epigenetic modifications.
     Based on the limited evidence from these epigenetics studies, long-term exposure to PMi0 may
result in epigenetic changes. PM2.5 also potentially affects some DNA methylation content. As
epigenetic research progresses, future studies examining the relationship between PM and DNA
methylation will be important in more thoroughly characterizing these associations.
     The effect of ambient PM on heritable DNA mutations and the epigenome has been well
characterized in a Canadian steel mill area. Mice exposed to ambient PM plus gases developed
paternally-derived heritable DNA mutations and epigenetic  changes in sperm DNA that were not
observed in mice exposed to ambient air that was HEPA-filtered.  This is the first animal toxicology
study showing heritable effects of PM exposure on DNA mutation and the epigenome.  Because the
epigenetics field is so new, further work in this emerging area will expand on these  PM-dependent
methylation changes to determine if the results can be recapitulated at other urban sites.


7.5.4.  Summary and  Causal Determinations



7.5.4.1.   PM2.5

     The 2004 PM AQCD reported on original and follow-up analyses for three prospective cohort
studies that reported positive relationships between PM2.5 and lung cancer mortality. Several recent,
well-conducted epidemiologic studies have extended the evidence for a positive association between
PM2.5 and lung cancer mortality (Section 7.5.1.1). Generally, studies have not reported associations
between long-term exposure to PM2.5 or PM10 and lung cancer incidence (Section 7.5.1.1). Animal
toxicological studies did not focus on specific size fractions of PM, but rather examined ambient
PM, wood smoke, and DE particles (Section 7.5.2). A number of recent studies indicate that ambient
urban PM, emissions from wood/biomass burning, emissions from coal combustion, and gasoline
and DE are mutagenic and that PAHs are genotoxic (Section 7.5.2). These findings  are consistent
with earlier studies that concluded that ambient PM and PM from specific combustion  sources are
mutagenic and genotoxic and provide biological plausibility for the results observed in the
epidemiologic studies. A limited number of epidemiologic and toxicological studies on the
epigenome demonstrate that PM induces changes in methylation (Section 7.5.3), anew area of
research that will likely be expanded in the future. However, it has yet to  be determined how these
alterations in the genome could influence the initiation and promotion of cancer. Overall, the
evidence is suggestive of a causal relationship between relevant PM  exposures and
cancer, with the strongest evidence from the epidemiologic studies of lung cancer
mortality. This evidence is limited by the non-specific measure of PM size fraction in  some of the
epidemiologic studies and most of the animal toxicological studies, and the inconsistency in
evidence with recent epidemiologic studies for an effect on cancer incidence. There is no
epidemiologic evidence for cancer related to long-term exposure to PM in organs or systems other
than the lung.
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7.5.4.2.   PM10.2.5
      The 2004 PM AQCD did not report long-term exposure studies for PMio_2.s. No epidemiologic
studies have been conducted to evaluate the effects of long-term PMi0_2.5 exposure and cancer. The
evidence is inadequate to assess the association between PWWsand UFP exposures and
cancer.

7.5.4.3.   UFPs
      The 2004 PM AQCD did not report long-term exposure studies for UFPs. No epidemiologic
studies have been conducted to evaluate the effects of long-term UFP and cancer. The evidence is
inadequate to determine if a causal relationship exists between long-term UFP
exposures and cancer
7.6.  Mortality
      In the 1996 PM AQCD, results were presented for three prospective cohort studies of adult
populations: the Six Cities Study (Dockery et al., 1993, 044457); the ACS Study (Pope et al, 1995,
045159); and the AHSMOG Study (Abbey et al., 1995, 000669). The 1996 AQCD concluded that
the chronic exposure studies, taken together,  suggested associations between increases in mortality
and long-term exposure to PM25, though there was no evidence to support an association with PMi0_
2.5 (U.S. EPA, 1996, 079380).
      Discussions of mortality and long-term exposure to PM in the 2004 PM AQCD emphasized
the results of four U.S. prospective cohort studies, but the greatest weight was placed on the findings
of the ACS and the Harvard Six Cities studies, which had each undergone extensive independent
reanalysis, and which were based on cohorts  that were broadly representative of the U.S. population.
The 2004 PM AQCD concluded that the results from the Seventh-Day Adventist (AHSMOG) cohort
provided some suggestive (but less conclusive) evidence for associations, while results from the
Veterans Cohort provided inconsistent evidence for associations between long-term exposures to
PM2.5 and mortality. Collectively, the 2004 PM AQCD found that these studies provided strong
evidence that long-term exposure to PM2.5 was associated with increased risk of human mortality.
Effect estimates for all-cause mortality ranged from 6 to 13% increased risk per 10 (ig/m3 PM2.5,
while effect estimates for cardiopulmonary mortality ranged from 6 to 19% per 10 (ig/m3 PM2.5. For
lung cancer mortality, the effect estimate was a 13% increase per 10 (ig/m3 PM25, based upon the
results of the extended analysis from the ACS cohort (Pope et al., 2002, 024689). With regard to
PM10_2.5, the 2004 PM AQCD reported that no association was observed between mortality  and long-
term exposure to PMi0_2.s in the ACS study (Pope et al., 2002, 024689). while a positive but
statistically non-significant association was reported in males in the AHSMOG cohort (McDonnell et
al., 2000, 010319).  Thus, the 2004 PM AQCD concluded that there was insufficient evidence for
associations between long-term exposure to PMi0_2.s and mortality. Overall, the 2004 PM AQCD
concluded that there was strong epidemiologic evidence for associations between long-term
exposures to PM2 5  and excess all-cause and cardiopulmonary mortality.
      At the time of the 2004 PM AQCD, only a limited number of the chronic-exposure cohort
studies had considered direct measurements of constituents of PM, other than sulfates. With regard
to source-oriented evaluations of mortality associations with long-term exposure, the 2004  PM
AQCD noted only the study by Hoek et al. (2002, 042364). in which the authors concluded that
long-term exposure to traffic-related air pollution may shorten life expectancy. However, Hoek et al.
(2002, 042364) also noted that living near a major road might include other factors that contribute to
mortality associations. There was not sufficient evidence at the time of the 2004 PM AQCD to draw
conclusions on effects  associated with specific components or sources of PM.
      New epidemiologic evidence reports a consistent association between long-term exposure to
PM25 and increased risk of mortality. There is little evidence for the long-term effects of PMi0_2.s on
mortality. Although this section focuses on mortality outcomes in response to long-term exposure to
PM, it does not evaluate studies that examine the association between PM and infant mortality.
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These studies are evaluated in Section 7.5 because it is possible that in utero exposures contribute to
infant mortality. A summary of the mean PM concentrations reported for the studies characterized in
this section is presented in Table 7-8.
Table 7-8. Characterization of ambient PM concentrations from studies of mortality and long-term
exposures to PM.
Study
Location
Mean Concentration
(ug/m3)
Upper Percentile Concentrations (ug/m3)
PM2.5
Brunekreef et al. (2009, 1919471
Chen et al. (2005, 0879421
Eftim et al. (2008, 099104)
Enstrom (2005, 087356)
Cosset al. (2004, 055624)
Janes etal. (2007, 0909271
Jerrett et al. (2005, 1894051
Krewski et al. (2009, 1911931
Laden et al. (2006, 0876051
Lipfert et al. (2006, 0882181
Miller etal. (2007, 0901301
Pope et al. (2004, 0558801
Schwartz et al. (2008, 1569631
Zeger etal. (2007,157176)
Zeger etal. (2008, 191951)
The Netherlands
Multicity, CA
U.S.
CA
U.S.
U.S.
Los Angeles, CA
U.S.
Multicity, U.S.
U.S.
U.S.
U.S.
Multicity, U.S.
U.S.
U.S.
28
29.0
13.6-14.1
23.4
13.7
14.0

14.02
10.2-29.0
14.3
13.5
17.1
17.5

13.2
95th: 32
99th: 33
Max: 37

Max: 19. 1-25.1
Max: 36.1
75th: 15.9

Max: 27.1
75th: 16.00
90th: 26.75
95th: 27.89
Max: 30.01


75th: 18.3
Max: 28.3

Max: 40
17.0
75th: 14.9
PMiO-2.5
Chen et al. (2005, 0879421
Lipfert et al. (2006, 088218)
Multicity, CA
U.S.
25.4
16.0


PM10
Chen et al. (2005, 087942)
Gehring et al. (2006, 089797)
Goss etal. (2004,055624)
Puett et al. (2008, 1568911
Zanobetti et al. (2008, 1561771
Multicity, CA
North Rhine, Germany
U.S.
NEU.S.
U.S.
52.6
43.7-48.0
24.8
21.6
29.4

Max: 52.5-56.1
75th: 28.9


December 2009
7-83

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7.6.1.  Recent Studies of Long-Term Exposure to PM and Mortality

      Studies since the last PM AQCD include results of new analyses and insights for the ACS and
Harvard Six Cities studies, further analyses from the AHSMOG and Veterans study cohorts, as well
as analyses of a Cystic Fibrosis cohort and subsets of the ACS from Los Angeles and New York City.
In the original analyses of the Six Cities and ACS cohort studies, no associations were found
between long-term exposure to PMi0_2.5 and mortality, and the extended and follow-up analyses did
not evaluate associations with PMi0_2.5. The historical and more recent results for PM2.5 of both the
ACS and the Harvard Six Cities studies are compiled in Figure 7-6. Moreover, since the last PM
AQCD, there is a major new cohort that investigates the effects of PM2.5 on cardiovascular mortality
in the literature: the WHI  study (Miller et al, 2007, 090130). Most recently, an ecologic cohort study
of the nation's Medicare population has been completed (Eftim et al., 2008, 099104). These new
findings further strengthen the evidence linking long-term exposure to PM2 5 and mortality, while
providing indications that the magnitude of the PM2 5-mortality association is larger than previously
estimated (Figure 7-7). Two recent reports from the AHSMOG and Veterans study cohorts have
provided some limited evidence for associations between long-term exposure to PMi0_2.5 and
mortality. The original analyses of the AHSMOG cohort study found positive associations between
long-term concentrations of PMi0 and 15-yr mortality  due to natural causes and lung cancer (Abbey
et al., 1999, 047559). McDonnell et al. (2000, 010319) reanalyzed these data and concluded that
previously observed association of long-term ambient PMi0 concentrations with mortality for males
were best explained by a relationship of mortality with the fine fraction of PMi0 rather than the
thoracic coarse fraction of PMi0. Recent reports from the AHSMOG study cohort, as well as the
Nurses' Health Study and a cohort of women in Germany have provided some evidence for
associations between long-term exposure to PMi0 and mortality among women.
      Harvard Six Cities: Afollow-up study has used updated air pollution and mortality data; an
additional 1,368 deaths occurred during the follow-up period (1990-1998) versus 1,364 deaths in the
original study period  (1974-1989) (Laden  et al., 2006, 087605). Statistically significant associations
are reported between long-term exposure to PM2 5 and mortality for data for the two periods
(RR =1.16 [95%  CI:  1.07-1.26] per  10 ug/m3 PM2.5). Of special note is a statistically significant
reduction in mortality risk reported with reduced long-term  PM25 concentrations (RR = 0.73 [95%
CI: 0.57-0.95] per 10 ug/m3 PM25). This is equivalent to an RR of 1.27 for reduced mortality risks
with reduced long-term PM2 5 concentrations. This reduced mortality risk was observed for deaths
due to cardiovascular and respiratory causes, but not for lung cancer deaths. The PM2 5
concentrations for recent years were estimated from visibility data, which introduces some
uncertainty in the interpretation of the results from this study. Coupled with the results of the original
analysis (Dockery et al., 1993, 044457). this study strongly suggests that a reduction in PM25
pollution yields positive health benefits.
      ACS Extended AnalyseS/ReanalysiS II: Two new analyses further evaluated the
associations of long-term PM25 exposures with risk of mortality in 50 U.S. cities reported by Pope
and colleagues (2002, 024689). adding new details about deaths from specific cardiovascular and
respiratory  causes (Krewski, 2009, 190075; Pope et al., 2004, 055880). Pope  et al. (2004, 055880)
reported positive associations  with deaths  from specific cardiovascular diseases, particularly
ischemic heart disease (IHD), and a group of cardiac conditions including  dysrhythmia, heart failure
and cardiac arrest (RR for cardiovascular mortality = 1.12, 95% CI 1.08-1.15 per 10 ug/m3 PM25),
but no PM associations were found with respiratory mortality.
      In an additional reanalysis that extended the follow-up period for the ACS cohort to 18 yr
(1982-2000) (Krewski et al., 2009, 191193). investigators found effect estimates that were similar,
though generally higher, than those reported in previous ACS analyses. This reanalysis also included
data for seven ecologic (neighborhood-level) contextual (i.e., not individual-lev el) covariates,  each
of which represents local factors known or suspected to influence mortality, such as poverty level,
educational attainment, and unemployment. The effect estimate for all cause mortality, based on
PM2.5 concentrations  measured in 1999-2000 was 1.03 (95% CI: 1.01-1.05). The corresponding
effect estimates for deaths due to IHD and lung  cancer were 1.15 (95% CI: 1.04-1.18) and 1.11
(95% CI: 1.04-1.18),  respectively. In earlier analyses of this cohort, investigators found that
increasing education levels appeared to reduce the effect of PM2 5 exposure on mortality. Results
from this reanalysis show a similar pattern, although with somewhat less certainty, for all causes of
death except IHD, for which the pattern was reversed. Overall, although the addition of random
effects modeling and  contextual covariates to the ACS model made most effect estimates higher (but
December 2009                                 7-84

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some lower), they were not statistically different from the earlier ACS effect estimates. Thus, these
new analyses, with their more extensive consideration of potentially confounding factors,  confirm
the published ACS PM2.5-mortality results to be robust.
       California Cancer Prevention Study: In a cohort of elderly people in 11 California
counties (mean age 73 yr in 1983), an association was reported for long-term PM25 exposure with
all-cause deaths from 1973-1982 (RR = 1.04 [95%  CI:  1.01-1.07] per 10 ug/m3 PM2.5) (Enstrom,
2005, 087356). However, no significant associations were reported with deaths in later time periods
when PM2.5 levels had decreased in the most polluted counties (1983-2002) (RR =  1.00 [95% CI:
0.98-1.02] per 10 (ig/m3 PM25). The PM25 data were obtained from the EPAs Inhalation Particle
Network (collected 1979-1983), and the locations represented a subset of data used in the  50-city
ACS study (Pope et al, 1995, 045159). However, the use of average values for California counties
as exposure surrogates likely leads to  significant exposure error, as many California counties are
large and quite topographically  variable.
Cohort
Study
                                              Years    Mean
           Effect Estimate (95% CI)
SCS   Original
      Reanalysis
      Temporal Changes
      Extended
      6-Cities Medicare
ACS   Original
      Reanalysis
      Extended
      Extended
      Intra-metro LA
      ACS Medicare
      Reanalysis II
      Reanalysis II - LA
      Reanalysis II - NYC
SCS   Original
      Reanalysis
ACS   Original
      Reanalysis
      Extended
      Extended
      Intra-metro LA
      Reanalysis II
      Reanalysis II - LA
      Reanalysis II - NYC
SCS   Extended
ACS   Reanalysis
      Extended
ACS   Extended
      Intra-metro LA
      Reanalysis II
      Reanalysis II - LA
      Reanalysis II - NYC
SCS   Original
      Reanalysis
      Extended
ACS   Original
      Extended
      Extended
      Intra-metro LA
      Reanalysis II
      Reanalysis II - LA
      Reanalysis II - NYC
SCS   Extended
ACS   Extended
      Extended
      Intra-metro LA
      Reanalysis II
CPD=Cardio-Pulmonary Disease
CVD=Cardiovascular Disease
IHD=lschemic Heart Disease
                      Dockery et al. (1993, 044457)   1974-1991
                      Krewski et al. (2000, 012281)   1974-1991
                      Villeneuve et al. (2002,042576) 1974-1991
                      Laden et al. (2006,087605)    1974-1998
                      Eftim et al. (2008,099104)     2000-2002
                      Pope et al. (1995,045159)     1982-1989
                      Krewski et al.(2000,012281)   1982-1989
                      Pope et al. (2002,024689)     1979-1983
                      Pope et al. (2002,024689)     1999-2000
                      Jerrett et al. (2005,189405)    1982-2000
                      Eftim et al. (2008,099104)     2000-2002
                      Krewski et al. (2009,190075)   1982-2000
                      Krewski et al. (2009,190075)   1982-2000
                      Krewski et al. (2009,190075)   1982-2000
                      Dockery etal. (1993,044457)    1974-1991
                      Krewski et al. (2000,012281)    1974-1991
                      Pope etal. (1995,045159)      1982-1989
                      Krewski et al. (2000,012281)    1982-1989
                      Pope et al. (2002,024689)      1979-1983
                      Pope et al. (2002,024689)      1999-2000
                      Jerrett et al. (2005,189405)     1982-2000
                      Krewski et al. (2009,190075)    1982-2000
                      Krewski et al. (2009,190075)    1982-2000
                      Krewski et al. (2009,190075)    1982-2000
                      Laden et al. (2006,087605)    1974-1998
                      Krewski et al. (2000, 012281)   1982-1989
                      Pope et al. (2004,055880)     1982-2000
                      Pope et al. (2004,055880)       1982-2000
                      Jerrett et al. (2005,189405)      1982-2000
                      Krewski et al. (2009,190075)     1982-2000
                      Krewski et al. (2009,190075)     1982-2000
                      Krewski et al. (2009,190075)     1982-2000
                      Dockery et al. (1993, 044457)   1974-1991
                      Krewski et al. (2000, 012281)   1974-1991
                      Laden et al. (2006,087605)    1974-1998
                      Pope et al. (1995,045159)     1982-1989
                      Pope et al. (2002,024689)     1979-1983
                      Pope et al. (2002,024689)     1999-2000
                      Jerrett et al. (2005,189405)    1982-2000
                      Krewski et al. (2009,190075)   1982-2000
                      Krewski et al. (2009,190075)   1982-2000
                      Krewski et al. (2009,190075)   1982-2000
                      Laden et al. (2006,087605)      1974-1998
                      Pope et al. (2002,024689)       1979-1983
                      Pope et al. (2002,024689)       1999-2000
                      Jerrett et al. (2005,189405)      1982-2000
                      Krewski et al. (2009,190075)     1982-2000
 18.6
 18.6
 18.6
 17.6
 14.1
 18.2
 18.2
 21.1
 14.0
 19.0
 13.6
 14.0
 20.5
 12.8
18.6
18.6
18.2
18.2
21.1
14.0
19.0
14.0
20.5
12.8  <
 17.6
 18.2
 17.1
  17.1
  19.0
  14.0
  20.5
  12.8
 18.6
 18.6
 17.6
 18.2
 21.1
 14.0
 19.0
 14.0
 20.5
 12.8 <
  17.6
  21.1
  14.0
  19.0
  14.0
                                                                                                          All Cause
                                                                                       CPD
                                                                                        CVD


                                                                                        IHD
                                                                                  Lung Cancer
                                                                                       Other
                                                           1
                                                          0.5
                                                       \                 \
                                                      1.0               1.5
                                                      Relative Risk Estimate
                                                        I
                                                       2.0
Figure 7-6.      Mortality risk estimates associated with long-term exposure to PM2.6 from the
                  Harvard Six Cities Study (SCS) and the American Cancer Society Study (ACS).
December 2009
7-85

-------
Study
                            Cohort
                      Subset
                                                                   Mean     Effect.Estimate (95% Cl)
McDonnell et al. (2000,010319)  AHSMOG
Brunekreef et al. (2009,191947)  NLCS-AIR
Enstrom (2005, 087356)
Jerrett etal. (2005.189405)
Krewski et al. (2009,191193)
Laden etal. (2006.087605)
Lipfertetal. (2006,088218)

Eftimetal. (2008.099104)

Krewski etal. (2009.191193)
Gossetal. (2004.055624)
Zegeretal. (2008,191951)
                            CA Cancer Prevention
                            ACS-LA
                            ACS Reanalysis II-LA
                            Harvard 6-Cities
                            Veterans Cohort

                            Medicare Cohort

                            ACS Reanalysis II
                            U.S. Cystic Fibrosis
                            MCAPS
Krewski etal. (2009. 191193)
Brunekreef et al. (2009, 191947

Pope etal. (2004. 055880)
Laden etal. (2006.087605)
Naess etal. (2007,090736)
Miller etal. (2007.090130)
Chen etal. (2005.087942)

Jerrett etal. (2005.189405)
Krewski etal. (2009.190075)
Pope etal. (2004.055880)
Krewski et al. (2009,191193)

McDonnell et al. (2000,010319)
Jerrett etal. (2005.189405)
Krewski et al. (2009,191193)
Brunekreef et al. (2009,191947)

Laden etal. (2006.087605)
McDonnell et al. (2000,010319)
Brunekreef et al. (2009,191947)

Jerrett etal. (2005.189405)
Krewski et al. (2009,191193)
Laden etal. (2006.087605)
Naess etal. (2007.090736)
Krewski et al. (2009,191193)

Brunekreef et al. (2009,191947

Jerrett etal. (2005.189405)
Laden etal. (2006.087605)
Krewski etal. (2009.191193)
ACS Reanalysis II-NYC
NLCS-AIR

ACS
Harvard 6-Cities
Oslo, Norway
                            WHI
                            AHSMOG

                            ACS-LA
                            ACS Reanalysis II-LA
                            ACS
                            ACS Reanalysis II
                            ACS Reanalysis II-NYC
                            AHSMOG
                            ACS-LA
                            ACS Reanalysis II-LA
                            ACS Reanalysis II
                            ACS Reanalysis II-NYC
                            NLCS-AIR

                            Harvard 6-Cities
                            AHSMOG
                            NLCS-AIR

                            ACS-LA
                            ACS Reanalysis II-LA
                            Harvard 6-Cities
                            Oslo, Norway
                            ACS Reanalysis II
                            ACS Reanalysis II-NYC
                            NLCS-AIR

                            ACS-LA
                            Harvard 6-Cities
                            ACS Reanalysis II
                      Males
                      Full Cohort
                      Case Cohort
                      1973-1982
                      1983-2002
                      1973-2002
                      ACS Sites
                      6-Cities sites
                                                  65+, Eastern
                                                  65+, Central
                                                  65+, Western
                                                  65-74, Eastern
                                                  65-74, Central
                                                  65-74, Western
                                                  65+, Eastern
                                                  75-84, Central
                                                  75-84, Western
                                                  85+, Eastern
                                                  85+, Central
                                                  85+, Western

                                                  Full Cohort
                                                  Case Cohort
                                                  Males, 51 -70 yrs
                                                  Males, 71 -90 yrs
                                                  Females, 51 -70 yrs
                                                  Females 71 -90 yrs
                                                  Females
                                                  Females
                                                  Males
                      Males
                      Full Cohort
                      Case Cohort

                      Males
                      Full Cohort
                      Case Cohort
32.0
28.3
28.3
23.4
23.4*
23.4*
19.0
20.5
16.4
14.3
14.3
13.6
14.1
14.0
13.7
14.0
10.7
13.1
14.0
10.7
13.1
14.0
10.7
13.1
14.0
10.7
13.1
12.8
28.3
28.3
17.1
16.4
14.3
14.3
14.3
14.3
13.5
29.0
29.0
19.0
20.5
17.1
14.0
12.8

19.0
20.5
14.0
12.8«r-
28.3
28.3 -
16.4
32.0
28.3
28.3-
19.0
20.5
                                                                                                                     All Cause
                                                  Males, 51-70 yrs    14.3
                                                  Males 71-90 yrs     14.3
                                                  Females, 51-70 yrs  14.3
                                                  Females, 71-90 yrs  14.3
                                                                    14.0
                                                                    12.8-s-
                                                                    28.3
                                                                    28.3
                                                                    19.0
                                                                    16.4
                                                                    14.0
                      Full Cohort
                      Case Cohort
                                                                                  4
                                                                                  >.
                                                                                   i _
                                                                                   I.
                                                                                  -i.
                                                                                  4.
                                                                                   i
                                                                                                                     CV
                                                                                         CHD

                                                                                         IHD
 CPD




 Respiratory


-Lung Cancer
                                                                                         Other
CV=Cardiovascular; CHD= Coronary Heart Disease
IHD=lschemic Heart Disease; CPD=Cardio-Pulmonary Disease
* PM2 5 data from 1973-1982 applied to all subsequent time periods
                                                                      0.5
                                                      1,0        1,5         2.0
                                                         Relative Risk Estimate
                                                                                                                    2.5
Figure 7-7.      Mortality risk estimates, long-term  exposure to PM2.s in recent cohort studies.
December 2009
                                   7-86

-------
      AHSMOG: In this analysis for the Seventh-Day Adventist cohort in California, a positive,
statistically significant, association with coronary heart disease mortality was reported among
females (92 deaths; RR = 1.42 [95% CI:  1.06-1.90] per 10 ug/m3 PM25), but not among males
(53 deaths; RR = 0.90 [95% CI: 0.76-1.05] per 10 ug/m3 PM2.5) (Chen et al., 2005, 087942).
Associations were strongest in the subset of postmenopausal women (80 deaths; RR = 1.49 [95% CI:
1.17-1.89] per 10  ug/m3 PM2.5). The authors speculated that females may be more sensitive to air
pollution-related effects, based on differences between males and females in dosimetry and
exposure. As was  found with PM2.5, a positive association with coronary heart disease mortality was
                                                                                        10-2.5,
reported for PM10_25 and PM10 among females (RR = 1.38 [95% CI: 0.97-1.95] per 10 ug/m3 PM
RR = 1.22 [95% CI: 1.01-1.47] per 10 ug/m3 PM10), but not for males (RR = 0.92 [95% CI: 0.66-
1.29] per 10 ug/m3 PM10.2.5; RR = 0.94 [95% CI: 0.82-1.08] per 10 ug/m3 PM10);  associations were
strongest in the subset of postmenopausal women (80 deaths) (Chen et al., 2005, 087942).
      U.S. Cystic FibrOSJS cohort: A positive, but not statistically significant, association was
reported for PM2.5 in this study (RR = 1.32 [95% CI: 0.91-1.93] per 10 ug/m3 PM2.5) that primarily
focused on evidence of exacerbation of respiratory symptoms (Goss et al., 2004, 055624). No clear
association was reported for PMi0. However, only 200 deaths had occurred in the cohort of over
11,000 people (average age in cohort was 18.4 yr), so the power of this study to detect associations
was relatively low.
      Women's Health Initiative (WHI) Study: This nationwide cohort study considered 65,893
post-menopausal women with no history of cardiovascular disease who lived in 36 U.S. metropolitan
areas from 1994 to 1998 (Miller et al., 2007, 090130). The study  had a median subject follow-up
time of 6 years. Miller and colleagues assessed each woman's exposure to air pollutants using the
monitor located nearest to their residence. Hazard ratios were estimated for the first cardiovascular
event, adjusting for age, race or ethnic group, smoking status, educational level, household income,
body-mass index, and presence or absence of diabetes, hypertension, or hypercholesterolemia.
Overall, this study concludes that "long-term exposure to fine particulate air pollution is associated
with the incidence of cardiovascular disease and death among postmenopausal women." In terms of
effect size, the study found that each increase of 10  ug/m3 of PM25 was associated with a 24%
increase in the risk of a cardiovascular event (hazard ratio, 1.24 [95% CI: 1.09-1.41]) and a 76%
increase in the risk of death from cardiovascular disease (hazard ratio, 1.76 [95% CI: 1.25-2.47]).
While this study found results confirmatory to the ACS and Six Cities Study, it reports much larger
relative risk estimates per ug/m3 PM2 5. In addition,  since the study included only women without
pre-existing cardiovascular disease, it could potentially be a healthier cohort population than that
considered by the ACS and Six Cities Study. Indeed, the WHI Study reported only 216
cardiovascular deaths in 349,643 women-yr of follow-up, or a rate of 0.075% deaths per year (Miller
et al., 2007, 090130). while the ACS Study reported that 10% of subjects died of cardiovascular
disease over a 16-yr follow-up period, yielding a rate of 0.625% per year, or approximately 8 times
the cardiovascular mortality rate of the WHI population (Pope et  al., 2004, 055880). Thus, PM2.5
impacts may yield higher relative risk estimates in the WHI population because the PM2 5 risk is
being compared to a much lower prevailing risk  of cardiovascular death  in this select study
population.
      The WHI study not only confirms the ACS and Six City Study associations with mortality in
yet another well characterized cohort with detailed individual-level information, it also has been able
to consider the individual medical records of the thousands  of WHI subjects over the period of the
study. This has allowed the researchers to examine not only mortality, but also related morbidity in
the form of heart problems (cardiovascular events) experienced by the subjects during the study. As
reported in this paper, this examination confirmed that there is an increased risk of cardiovascular
morbidity, as well (Section 7.2.9). These morbidity  co-associations with  PM2 5 in  the same
population lend even greater support to the biological plausibility of the air pollution-mortality
associations found in this study.
      Medicare Cohort Studies: Using Medicare data, Eftim and co-authors (2008, 099104)
assessed the association of PM25 with mortality for  the same locations included in the ACS and Six
City Study. For these locations, they estimated the chronic effects of PM25 on mortality  for the
period 2000-2002 using mortality data for cohorts of Medicare participants and average PM25 levels
from monitors in the same counties included in the two studies. Using aggregate counts of mortality
by county for three age groups, they estimated mortality risk associated with air pollution adjusting
for age and sex and area-level covariates (education, income level, poverty, and employment), and
controlled for potential confounding by cigarette smoking by including standardized mortality ratios
December 2009                                  7-87

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for lung cancer and COPD. This study is, therefore, an ecological analysis, similar to past published
cross-sectional analyses, in that area-level covariates (education, income level, poverty, and
employment) are employed as controlling variables, since individual level information is not
available from the Medicare database (other than age and sex), which includes virtually all
Americans aged 65  or greater. Exposures are also ecological in nature, as central site data are used as
indices of exposure. These results indicated that a 10 (ig/m3 increase in the yearly average PM25
concentration is associated with 10.9% (95% CI: 9.0-12.8) and with 20.8% (95% CI: 14.8-27.1)
increases in all-cause mortality for the ACS and Six Cities  Study counties, respectively. The
estimates are somewhat higher than those reported by the original investigators, and there may be
several possible explanations for this apparent increase, especially that this is an older population
than the ACS cohort. Perhaps the most likely explanation is that the lack of personal confounder
information (e.g., past personal smoking information) led to an insufficient control for the effects of
these other variables' effects on mortality, inflating the pollution effect estimates somewhat, similar
to what has been found in  the ACS analyses when only ecological-level control variables were
included. The ability of the Eftim et al. (2008, 099104) study results to qualitatively replicate the
original individual-level cohort study (e.g., ACS and Six Cities Study) results suggests that past
ecological cross-sectional  mortality study results may also  provide useful insights into the nature of
the association, especially  when used for consideration of time trends, or for comparisons of the
relative (rather than absolute) sizes of risks between different pollutants or PM components in health
effects associations.
      Janes et al. (2007, 090927) used the same nationwide Medicare mortality data to examine the
association between monthly averages of PM2.5 over the preceding 12 mo and monthly mortality
rates in 113 U.S. counties from 2000 to 2002. They decomposed the association between PM2.5 and
mortality into two components:  (1) the association between "national trends" in PM2.5 and mortality;
and (2) the association between "local trends," defined as county-specific deviations from national
trends. This second component is posited to provide evidence  as to whether counties having steeper
declines in PM2 5 also have steeper declines in mortality relative to the national trend. They report
that the exposure effect estimates are different at these two spatiotemporal scales, raising concerns
about confounding bias in  these analyses. The authors assert that the association between trends in
PM2 5 and mortality at the  national scale is more likely to be confounded than is the association
between trends in PM25 and mortality  at the local scale and, if the association at the national scale is
set aside, that there  is little evidence of an association between 12-month exposure to PM25 and
mortality in this analysis. However, in response, Pope and Burnett (2007, 090928) point out that
such use of long-term time trends as the primary source of exposure variability has been avoided in
most other air  pollution epidemiology  studies because of such concerns  about potential confounding
of such time-trend associations.
      By linking monitoring data to the U.S. Medicare system by county of residence, Zeger et al.
(2007, 157176) analyzed Medicare mortality records, comprising over 20 million enrollees in the
250 largest counties during 2000-2002. The authors estimated log-linear regression models having
age-specific county level mortality rates as the outcome and, as the main predictor, the average PM2 5
pollution level in each county during 2000. Area-level covariates were used to adjust for socio-
economic status and smoking. The authors reported results under several degrees of adjustment for
spatial confounding and with stratification into eastern, central and western U.S. counties. A
10 ug/m3 increase in PM25 was associated with a 7.6% increase in mortality  (95% CI: 4.4-10.8).
When adjusted for spatial  confounding, the estimated log-relative risks dropped by 50%. Zeger et al.
(2007, 157176) found a stronger association in the eastern counties than nationally, with no evidence
of an association in western counties.
      In a subsequent report, Zeger et al. (2008, 191951) created a new retrospective cohort, the
Medicare Cohort Air Pollution Study (MCAPS), consisting of 13.2 million persons residing in 4,568
ZIP codes in urban areas having geographic centroids within 6 miles of a PM2 5 monitor.  Using this
cohort, they investigated the relationship between 6-yr avg exposure to PM2 5 and mortality risk over
the period 2000-2005. When divided by region, the associations between long-term exposure to
PM2 5 and mortality for the eastern and central ZIP codes were qualitatively similar to those reported
in the ACS and Six  Cities  Study, with  11.4% (95% CI: 8.8-14.1) and 20.4% (95% CI:  15.0-25.8)
increases per 10 (ig/m3 increase in PM25 in the eastern and  central regions, respectively. The  MCAPS
results included evidence of differing PM2 5 relative risks by age and geographic location, where risk
declines with increasing age category until there is no evidence of an association among persons
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> 85 yr of age, and there is no evidence of a positive association for the 640 urban ZIP codes in the
western region of the U.S.
      Using hospital discharge data, Zanobetti et al. (2008, 156177) constructed a cohort of persons
discharged with COPD using Medicare data between 1985 and 1999. Positive associations in the
survival analyses were reported for single year and multiple-year lag exposures, with a hazard ratio
for total mortality of 1.22 (95% CI: 1.17-1.27) per 10 ug/m3 increase in PMi0 over the previous
4 years.
      Veterans Cohort: A recent reanalysis of the Veterans cohort data focused on exposure to
traffic-related air pollution (traffic density based on traffic flow rate data and road segment length)
reported a stronger relationship between mortality with long-term exposure to traffic than with PM2 5
mass (Lipfert et al., 2006, 088218). A significant association was reported between total  mortality
and PM2.5 in single-pollutant models (RR =1.12 [95% CI: 1.04-1.20] per 10 ug/m3 PM2.5). This risk
estimate is larger than results reported in a previous study of this  cohort. In multipollutant models
including traffic density, the association with  PM2.5 was reduced and lost statistical significance.
Traffic emissions contribute to PM2 5 so it would be expected that the two would be highly
correlated, and, thus, these multipollutant model results should be interpreted with caution. In a
companion study, Lipfert et al. (2006, 088218) used data from EPA's fine particle speciation
network, and reported findings for PM2 5  which were similar to those reported by Lipfert et al. (2006,
088218). In this study (Lipfert et al., 2006, 088218). a significant association was reported between
long-term exposure to PMi0_2.5 and total mortality in a single-pollutant model (RR = 1.07, 95% CI:
1.01-1.12 per 10 ug/m3 PM10_2.5). However, the association became negative and not statistically
significant in a model  that included traffic density. As it would  be expected that traffic would
contribute to the PMi0_2.5 concentrations,  it is  difficult to interpret the results of these multipollutant
analyses.
      Nurses' Health Study Cohort: The Nurses' Health Study (Puett et al., 2008, 156891) is an
ongoing prospective cohort study examining the relation of chronic PMi0 exposures with all-cause
mortality and incident and fatal CHD  consisting of 66,250 female nurses in MSAs in the
northeastern region of the U.S. All cause mortality was statistically significantly associated with
average PMi0 exposures in the time period 3-48 mo preceding death. The association was strongest
with average PMi0 exposure in the 24 mo prior to death (hazard ratio 1.16 [95% CI: 1.05-1.28]) and
weakest with exposure in the month prior to death (hazard ratio 1.04 [95% CI: 0.98-1.11]). The
association with fatal CHD occurred with the greatest magnitude with mean exposure in the 24 mo
prior to death (hazard  ratio 1.42 [95% CI: 1.11-1.81]).
      Netherlands Cohort Study (NLCS): The Netherlands  Cohort Study (Brunekreef et al.,
2009, 191947) estimates the effects of traffic-related air pollution on cause specific mortality in a
cohort of approximately 120,000 subjects aged 55-69 yr at enrollment.  For a 10 ug/m3 increase in
PM25 concentration, the relative risk for natural-cause mortality in the full cohort was 1.06 (95% CI:
0.97-1.16), similar in magnitude to the results reported by the ACS. In a case-cohort analysis
adjusted for additional potential confounders, there were no associations between air pollution and
mortality.
      German Cohort: The North Rhine-Westphalia State Environment Agency  (LUANRW)
initiated a cohort of approximately 4,800 women, and assessed whether long-term exposure to air
pollution originating from motorized traffic and industrial sources was  associated with total and
cause-specific mortality (Gehring et al., 2006, 089797). They found that cardiopulmonary mortality
was associated with PM10 (RR = 1.52 [95% CI: 1.09-2.15] per  10 ug/m3 PM10).


7.6.2.  Composition and Source-Oriented Analyses of PM

      As discussed in the 2004 PM AQCD, only a very limited number of the chronic exposure
cohort studies have included direct measurements of chemical-specific PM constituents other than
sulfates, or assessments of source-oriented effects, in their analyses. One exception is the Veterans
Cohort Study, which looked at associations with some constituents, and traffic.
      Veterans Cohort: Using data from EPA's fine particle speciation network, Lipfert et al.
(2006, 088756) reported a positive association for mortality with sulfates.  Using 2002 data from the
fine particle  speciation network, positive associations were found between mortality and long-term
exposures to nitrates, EC, Ni and V, as well as traffic density and peak O3 concentrations. In
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multipollutant models, associations with traffic density remained significant, as did nitrates, Ni and
V in some models.
      Netherlands Cohort Study: Beelen et al. (2008, 156263) studied the association between
long-term exposure to traffic-related air pollution and mortality in a Dutch cohort. They used data
from an ongoing cohort study on diet and cancer with 120,852 subjects who were followed from
1987 to 1996. Exposure to BS, NO2, SO2, and PM2.5, as well as various exposure variables related to
traffic, were estimated at the home address. Traffic intensity on the nearest road was independently
associated with mortality. Relative risks (CI) for a 10 (ig/m increase in BS  concentrations
(difference between 5th and 95th percentile) were 1.05 (95% CI: 1.00-1.11) for natural cause, 1.04
(95% CI: 0.95-1.13) for cardiovascular, 1.22 (95% CI: 0.99-1.50) for respiratory, 1.03 (95% CI:
0.88-1.20) for lung cancer, and 1.04 (95% CI:  0.97-1.12) for mortality other than cardiovascular,
respiratory, or lung cancer. Results were similar for NO2 and PM2 5, but no associations were found
for SO2. Traffic-related air pollution and several traffic exposure variables were associated with
mortality in the full cohort, although the relative risks were generally small. Associations between
natural-cause and respiratory mortality were statistically significant for NO2 and BS. These results
add to the evidence that long-term exposure to traffic-related particulate air pollution is associated
with increased mortality.
      Given the general dearth of published source-oriented studies of the mortality impacts of long-
term PM exposure components, and given that the recent Medicare Cohort study now indicates that
such ecological cross-sectional studies can be  useful for evaluating time trends and/or comparisons
across pollution components, it may well be that examining past cross-sectional studies comparing
source-oriented components of PM may be informative. In particular, Ozkaynak and Thurston (1987,
072960). utilized the chemical speciation conducted in the Inhalable Particle (IP) Network to
conduct a chemical constituent and source-oriented evaluation on long-term PM exposure and
mortality in the U.S. They analyzed the 1980 U.S. vital statistics and available ambient air pollution
data bases for sulfates and fine, inhalable, and TSP mass. Using multiple regression analyses, they
conducted a cross-sectional analysis of the association between various particle measures and total
mortality. Results from the various analyses indicated the importance of considering particle size,
composition, and source information in modeling of particle pollution health effects. Of the
independent mortality predictors considered, particle exposure measures most related to the
respirable fraction of the aerosols, such as fine particles and sulfates, were most consistently and
significantly associated with the reported SMSA-specific total annual mortality rates. On the other
hand, particle mass measures that included PMi0_2.5 (e.g., total suspended particles and inhalable
particles) were often found to be non-significant predictors of total mortality. Furthermore, based on
the application of PM25 source apportionment, particles from industrial sources and from coal
combustion were indicated to be more significant contributors to human mortality than fine soil-
derived particles.


7.6.3.  Within-City  Effects of PM Exposure

      Much of the exposure gradient in the national-scale cohort studies was due to city-to-city
differences in regional air pollution, raising the possibility that some or all of the original PM-
survival associations may have been driven instead by cify-to-city differences in some unknown
(non-pollution) confounder variable. This has  been evaluated by three recent studies.
      ACS, LOS Angeles: To investigate this issue, two new analyses using ACS data focused on
neighborhood-to-neighborhood differences in  urban air pollutants, using data from 23 PM2 5
monitoring stations in the Los Angeles area, and applying interpolation methods (Jerrett et al., 2005,
189405) or land use regression methods (Krewski et al., 2009, 191193) to assign exposure levels to
study individuals. This resulted in both improved exposure assessment and  an increased focus on
local sources of PM25. Significant associations between PM25 and mortality from all causes and
cardiopulmonary diseases were reported with the magnitude of the relative  risks being greater than
those reported in previous assessments. In general, the associations for PM2 5 and mortality using
these two methods for exposure assessment were similar, though the use of land use regression
resulted in somewhat smaller hazard ratios and tighter CIs (see  Table 7-9). This indicates that city-to-
city confounding was not the cause of the associations found in the earlier ACS Cohort studies. This
provides evidence that reducing exposure error can result in stronger associations between PM2 5 and
mortality than generally observed in broader studies having less exposure detail.
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Table 7-9.    Comparison of results from ACS intra-urban analysis of Los Angeles and New York City
             using kriging or land use regression to estimate exposure.
Cause of
Death
All Cause
IHD
CPD
Lung Cancer
Los Angeles:
Hazard Ratio1 and 95% Confidence
Interval Using Kriging
(Jerrett et al, 2005, 189405)
1.11 (0.99-1.25)
1.25(0.99-1.59)
1.07(0.91-1.26)
1.20(079-1.82)
Los Angeles:
Hazard Ratio1 and 95% Confidence
Interval Using Land Use Regression
(Krewskietal.. 2009. 191193)
1.13(1.01-1.25)
1.26(1.02-1.56)
1.09(0.94-1.26)
1.31 (0.90-1.92)
New York City:
Hazard Ratio1 and 95% Confidence
Interval Using Land Use Regression
(Krewskietal.. 2009. 191193)
0.86(0.63-1.18)
1.56(0.87-2.88)
0.66(0.41-1.08)
0.90 (0.29-2.78)
1Hazard ratios presented per 10 [jg/m3 increase in PM25
2Model included parsimonious contextual covariates
3Model included parsimonious individual level (23) and ecologic (4) covariates
^Model included all 44 individual level and 7 ecologic covariates.


      ACS, New York: Krewski et al. (2009, 191193) applied the same techniques used in the land
use regression analysis of Los Angeles to an investigation conducted in New York City. Annual
average concentrations were calculated for each of 62 monitors from 3 yr of daily monitoring data
for 1999-2001. Those data were combined with land-use data collected from traffic counting
systems, roadway network maps, satellite photos of the study area, and local government planning
and tax-assessment maps to assign estimated exposures to the ACS participants. The investigators
did not observe elevated effect estimates for all cause, CPD or lung cancer deaths, but IHD did show
a positive association with PM2 5 concentration. The difference between the 90th and 10th percentiles
of the 3-yr avg PM2.5 concentration was 1.5 (ig/m3 and the difference between the minimum and
maximum values of the 3-yr avg PM2.5 concentration  was 7.8 (ig/m3. This narrow range in  PM2.5
exposure contrasts across the New York City metropolitan area and may well account for the
inconclusive results in this city-specific analysis. Relatively uniform exposures would reduce the
power of the statistical models to detect patterns of mortality relative to exposure and estimate the
association with precision.
      WHI Study: This study also investigated the within- versus between-city effects in its cities.
As shown in Figure 7-8, similar effects for both the within and between-city analyses demonstrate
that this  association is not due to some other (non-pollution) confounder differing between the
various cities, strengthening confidence in the overall pollution-effect estimates.
December 2009
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A Overall Effect

    12-

    11-
         0  3  6  9 12 15 IS 21 24 11 30
                                 B Between-City Effect

                                     12-
C Within-City Effect
                                                                    0  3  6  9  12 15 18 21 24 27 30
                                                                      3  6  9  12 15 IS 21 24 27 30

                                                                          PM  |im)
                                                                           Source: Miller et al. (2007, 090130)
                                                         Copyright © 2007 Massachusetts Medical Society. All rights reserved.
Figure 7-8.    Plots of the relative risk of death from cardiovascular disease from the Women's
              Health Initiative study displaying the between-city and within-city contributions
              to the overall association  between PM2.s and cardiovascular mortality windows of
              exposure-effects.
7.6.4.  Effects of Different Long-term Exposure Windows

      The delay between changes in exposure and changes in health has important policy
implications. Schwartz et al. (2008, 156963) investigated this issue using an extended follow-up of
the Harvard Six Cities Study. Cox proportional hazards models were fit to control for smoking, body
mass index, and other covariates. Penalized splines were fit in a flexible functional form to the
concentration response to examine its shape, and the degrees of freedom for the curve were selected
based on Akaike's information criterion (AIC). The researchers also used model averaging as an
alternative approach, where multiple models are fit explicitly and averaged, weighted by their
probability of being correct given the data. The lag relationship by model was averaged across a
range of unconstrained distributed lag models (i.e., same year, 1 yr prior, 2 yr prior, etc.). Results of
the lag comparison are shown in Figure 7-9 indicating that the effects of changes in exposure on
mortality are seen within 2 yr. The authors also noted that the concentration-response curve was
linear, clearly continuing below the level of the current U.S. air quality standard of 15 (ig/m3.
December 2009
                                         7-92

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                        1.20
                        1.15
                        1.10
                     JS
                      
-------
                     LO
                     O -
                     o
                     O
                 Cfl
                "l^
                 CD
                _>

                Is
                 CD
                01
                     to
                     O5
                     CD
                              2000
Figure 7-10.
                         2002      2004     2006      2008
                               Time (years)
     Source: Reprinted with Permission from Oxford University Press & the International Epidemiological Society from Roosli et al. (2005, 1 56923)

Time course of relative risk of death after a sudden decrease in air pollution
exposure during the year 2000, assuming a steady state model  (solid line) and a
dynamic model (bold dashed line).  The thin dashed line refers to the reference
scenario.
Table 7-10.   Distribution of the effect of a hypothetical reduction of 10 ug/m  PMio in 2000 on all-
             cause mortality 2000-2009 in Switzerland.
               Year
                   1999  2000  2001   2002   2003   2004   2005   2006   2007   2008   2009
Proportion of total effect (%)
                                       39.3    23.9
                                                   14.5
                                                               5.3
                                                                     3.2
                                                                           2.0
                                                                                 1.2
                                                                                       0.7
                                                                                             0.4
Relative risk (per 10 pg/m reduction in PM10)
                                  1.0
                                       0.9775  0.9863  0.9917  0.9950  0.9969  0.9981  0.9989  0.9993  0.9996  0.9997
Relative risk and proportion of total effect in each year are shown, assuming a time constant k of 0.5
                                                                              Source: Roosli et al. (2005,156923)
      In the reanalysis of the ACS cohort, the investigators calculated time windows of exposure as
average concentrations during successive 5-yr periods preceding the date of death (Krewski et al.,
2009, 191193). The investigators considered the time window with the best-fitting model (judged by
the AIC statistic) to be the period during which pollution had the strongest influence on mortality.
Overall, the differences between the time periods were small and demonstrated no definitive
patterns. High correlations between exposure levels in the three periods may have reduced the ability
of this analysis to detect any differences in the relative  importance of the time windows. The
investigators did not analyze any time periods smaller than 5 yr, so the results are not directly
comparable to those reported by Schwartz et al. (2008, 156963). Roosli et  al. (2005,  156923). and
Puett et al. (2008, 156891).
December 2009
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      Generally, these results indicate a developing coherence of the air pollution mortality
literature, suggesting that the health benefits from reducing air pollution do not require a long
latency period and would be expected within a few years of intervention.


7.6.5.  Summary and Causal Determinations



7.6.5.1.   PM2.5

      In the 1996 PM AQCD (U.S. EPA, 1996, 079380). results were presented for three prospective
cohort studies of adult populations: the Six Cities Study (Dockery et al, 1993, 044457): the ACS
Study (Pope et al., 1995, 045159): and the AHSMOG Study (Abbey et al., 1995, 000669). The 1996
AQCD concluded that the chronic exposure studies, taken together, suggested associations between
increases in mortality and long-term exposure to PM2 5, though there was no evidence to support an
association with PMi0_2.5 (U.S. EPA,  1996, 079380). Discussions of mortality and long-term
exposure to PM in the 2004 PM AQCD  emphasized the results of four U.S. prospective cohort
studies, but the greatest weight was placed on the findings  of the ACS and the Harvard Six Cities
studies, which had undergone extensive independent reanalysis, and which were based on cohorts
that were broadly representative of the U.S. population. Collectively, the 2004 PM AQCD found that
these studies provided strong evidence that long-term exposure to PM2 5 was associated with
increased risk of human mortality.
      The recent evidence is largely  consistent with past studies, further supporting the evidence of
associations between long-term PM2.5 exposure and increased risk of human mortality (Section 7.6)
in areas with mean concentrations from 13.2 to 29 ug/m3 (Figure 7-7). New evidence from the Six
Cities cohort study shows a relatively large risk estimate for reduced mortality risk with decreases in
PM2.5 (Laden et al., 2006, 087605). The results of new analyses from the Six Cities cohort and the
ACS study in Los Angeles suggest that previous and current studies may have underestimated the
magnitude  of the association (Jerrett et al., 2005, 189405).  With regard to mortality by cause-of-
death, recent ACS analyses indicate that cardiovascular mortality primarily accounts for the total
mortality association with PM2.5 among adults, and not respiratory mortality. The recent WHI cohort
study shows even higher cardiovascular risks per ug/m3 than found in the ACS study, but this is
likely due to the fact that  the study included only post-menopausal women without pre-existing
cardiovascular disease (Miller et al.,  2007, 090130). There is additional evidence for an association
between PM25 exposure and lung cancer mortality (Section 7.5.1.1). The WHI study also considered
within versus between city mortality, as well as morbidity co-associations with PM2 5 in the same
population. The first showed that the results are not due to  between city confounding,  and the
morbidity analyses show  the coherence  of the mortality association across health endpoints,
supporting the biological  plausibility of the air pollution-mortality associations found in these
studies.
      Results from a new study examining the relationship between life expectancy and PM2 5 and
the findings from a multiyear expert judgment study that comprehensively characterizes the size and
uncertainty in estimates of mortality  reductions associated  with decreases in PM25 in the U.S draw
conclusions that are consistent with an association between long-term exposure to PM2 5 and
mortality (Pope et al., 2009, 190107: Roman et al., 2008, 156921). Pope et al. (2009, 190107) report
that a decrease of 10 ug/m3 in the concentration of PM25 is associated with an estimated increase in
mean (± SE) life expectancy of 0.61  ± 0.20 year. For the approximate period of 1980-2000, the
average increase in life expectancy was  2.72 yr among the 211  counties in the analysis. The authors
note that reduced air pollution was only one factor contributing to increased life expectancies, with
its effects overlapping with those of  other factors.
      Roman et al. (2008, 156921) applied state-of-the-art expert judgment elicitation techniques to
develop probabilistic uncertainty distributions that reflect the broader array of uncertainties in the
concentration-response relationship.  This study followed best standard practices for expert
elicitations based on the body of literature accumulated over the past two decades. The resulting
PM25 effect estimate distributions, elicited from 12 of the world's leading experts on this issue, are
shown in Figure 7-11. They indicate both larger central estimates of mortality reductions for
decreases in long-term PM25 exposure in the U.S. (averaging almost 1% per ug/m3 PM25) than
reported (for example) by the ACS Study (i.e., 0.6% per ug/m3 PM2.5 in Pope et al. (2002, 024689).
December 2009                                  7-95

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and a wider distribution of uncertainty by each expert than provided by any one of the PM2.5
epidemiologic studies. However, a composite uncertainty range of the overall mean effect estimate
(i.e., based upon all 12 experts' estimates, but not provided in Figure 7-11) would be much narrower,
and closer to that derived from the ACS study than indicated for any one expert shown in Figure
7-11.
                              Group 1
                                          Group 2
   a.
   •C
   o
1

10-30
 Causality Likelihood 99%   75% 99%
 Expert         E      L
4-10 >10-30  4-30  4-30   4-30   4-16 >18-30
98% 98%   95%  95%   70%   35% 35%
  B      DIG      K
4-7 >7-30   4-30  4-30   4-30  4-30  pope Dockery
100% 100%   99%  99%   95%  90%  B| a|  et al..
   F      C    J    A    H   2002  1993
            Key: Closed circle = median; Open circle = mean: Box = interquartile range: Solid line = 90% credible interval
                                                       Source: Reprinted with Permission of ACS from Roman et al. (2008,1569211

Figure 7-11.    Experts' mean effect estimates and uncertainty distributions for the PM2.s
               mortality concentration-response coefficient for a 1  ug/m3 change in annual
               average  PM2.s.

      Overall, recent evidence supports the strong evidence reported in the 2004 PM AQCD
(U.S. EPA, 2004, 056905) that long-term exposure to PM2.5 is associated with an increased risk of
human mortality. When looking at the cause of death, the strongest evidence comes from mortality
due to cardiovascular disease, with additional evidence supporting an  association between PM2 5 and
lung cancer mortality (Figure 7-7). Fewer studies  evaluate the respiratory component of
cardiopulmonary mortality, and the evidence to support an association with long-term exposure to
PM2.5 and respiratory mortality is weak (Figure 7-7). Together these findings are consistent and
coherent with the evidence from epidemiologic, controlled human exposure, and animal
toxicological studies for the effects of short- and long-term exposure to PM on cardiovascular effects
presented in Sections 6.2 and 7.2, respectively. Evidence of short- and long-term exposure to PM2.5
and respiratory effects (Sections 6.3 and 7.3, respectively) and infant mortality (Section 7.4) are
coherent with the weak respiratory mortality effects. Additionally, the  evidence for short- and long-
term cardiovascular and  respiratory morbidity provides biological plausibility  for mortality due to
cardiovascular or respiratory disease. The most recent evidence for the association between long-
term exposure to PM2 5 and mortality is particularly strong for women. Collectively, the evidence is
sufficient to conclude that the relationship between long-term PM25 exposures and
mortality is causal.
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7.6.5.2.  PM10.2.5

     In the 2004 PM AQCD, results from the ACS and Six Cities study analyses indicated that
PMio_2.5 was not associated with mortality. Evidence is still limited to adequately characterize the
association between PM10_2.5 and PM sources and/or components. The new findings from AHSMOG
and Veterans cohort studies provide limited evidence of associations between long-term exposure to
PMio_2.5 and mortality in areas with mean concentrations from 16 to 25 (ig/m3. The evidence for
PMio25 is inadequate to determine if a causal relationship exists between long-term
exposures and mortality


7.6.5.3.  UFPs

     The 2004 PM AQCD did not report long-term exposure studies for UFPs. No epidemiologic
studies have been conducted to evaluate the effects of long-term UFP exposure and mortality. The
evidence is inadequate to determine if a causal relationship exists between long-term UFP
exposures and mortality
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Abbey DE; Mills PK; Petersen FF; Beeson WL. (1991). Long-term ambient concentrations of total suspended particulates
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Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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     Chapter 8.  Populations  Susceptible  to
                  PM-related  Health  Effects
      Interindividual variation in human responses to air pollutants indicates that some populations
are at increased risk for the detrimental effects of ambient exposure to an air pollutant (e.g., PM)
(Kleeberger and Ohtsuka, 2005, 130489). The NAAQS are intended to provide an adequate margin
of safety for both general populations and sensitive subgroups, or those individuals potentially at
increased risk for health effects in response to ambient air pollution (see Section 1.1). To facilitate
the identification of populations at the greatest risk for PM-related health effects, studies have
evaluated factors that contribute to the susceptibility  and/or vulnerability of an individual to PM. The
definition for both of these terms has been found to vary across studies, but in most instances
susceptibility refers to biological or intrinsic factors (e.g., lifestage, gender) while vulnerability
refers to non-biological or extrinsic factors (e.g., socioeconomic status [SES]) (see Table 8-1).
Additionally, in some cases, the terms  "at-risk" and sensitive populations have been used to
encompass these concepts more generally. However, in many cases a factor identified that increases
an individual's risk for morbidity or mortality effects from exposure to an air pollutant (e.g., PM)  can
not be easily categorized as a susceptibility or vulnerability factor. For example, a population that is
characterized as having low SES, traditionally defined as a vulnerability factor, may have less access
to healthcare resulting in the manifestation of disease (i.e., a susceptibility factor), but they may also
reside in a location that results in exposure to higher  concentrations of an air pollutant, increasing
their vulnerability. Therefore, the terms susceptibility and vulnerability are intertwined and at times
can not be distinguished from one another.
      As a result of the inconsistencies in the definition of susceptibility and vulnerability presented
in the literature as well as the inability to  clearly delineate whether an identified factor increases an
individual's susceptibility or vulnerability to an air pollutant, in this ISA, the term 'susceptible
population' will be used as a blanket term and defined as the following:

      Populations that have a greater likelihood of experiencing health effects related to exposure to
      an air pollutant  (e.g., PM) due to a variety of factors including, but not limited to: genetic or
      developmental factors, race, gender, lifestage,  lifestyle (e.g., smoking status and nutrition) or
      preexisting disease; as well as, population-level factors that can increase an individual's
      exposure to an air pollutant (e.g., PM) such as socioeconomic status [SES], which
      encompasses reduced access to health care, low educational attainment, residential location,
      and other factors.
 Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
 Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
 developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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Table 8-1.     Definitions of susceptible and vulnerable in the PM literature.
                                    Definition
                                     Reference
Susceptible: predisposed to develop a noninfectious disease

Vulnerable: capable of being hurt: susceptible to injury or disease
                          Merriam-Webster (2009, 1921461
Susceptible: greater likelihood of an adverse outcome given a specific exposure, in comparison with the general
population. Includes both host and environmental factors (e.g., genetics, diet, physiological state, age, gender,
social, economic, and geographic attributes).
Vulnerable: periods during an individual's life when they are more susceptible to environmental exposures.
                          American Lung Association (2001,0166261
Susceptible: innate (e.g., genetic or developmental) or acquired (e.g., age, disease or smoking or smoking) factors
that make individuals more likely to experience effects with exposure to PM.
Vulnerable: PM-related effects due to factors including socioeconomic status (e.g., reduced access to health care) or
particularly elevated exposure levels.

Susceptible: greater or lesser biological response to exposure.
Vulnerable: more or less exposed.

Vulnerable: to be susceptible to harm or neglect, that is, acts of commission or omission on the part of others that
can wound.

Susceptible:may be those who are significantly more liable than the general population to be affected by a stressor
due to life stage (e.g., children, the elderly, or pregnant women), genetic polymorphisms (e.g., the small but
significant percentage of the population who have genetic susceptibilities), prior immune reactions (e.g., individuals
who have been "sensitized" to a particular chemical), disease state (e.g., asthmatics), or prior damage to cells or
systems (e.g., individuals with damaged ear structures due to prior exposure to toluene, making them more sensitive
to damage by high noise levels).
Vulnerable: differential exposure and differential preparedness (e.g., immunization).

Susceptible: intrinsic (e.g.,  age, gender, pre-existing disease (e.g., asthma) and genetics) and extrinsic (previous
exposure and nutritional status) factors.

Susceptible:characteristics that contribute to increased risk of PM-related health effects (e.g., genetics, pre-existing
disease, age, gender, race, socioeconomic status, healthcare availability, educational attainment,  and housing
characteristics).
                                                                                 U.S. EPA. (2008, 1570721
                          U.S. EPA (2009, 1921491
                          Adav, LA. (2001,1921501
                          U.S. EPA (2003, 1921451
                          Kleeberger and Ohtsuka (2005, 1304891
                          Pope and Dockery (2006,1568811
       To examine whether air pollutants (e.g., PM) differentially affect certain populations,
epidemiologic studies conduct stratified analyses to identify the  presence or absence of effect
modification. A thorough evaluation of potential effect modifiers may help identify populations that
are more susceptible to an air pollutant (e.g., PM).  Although the design of toxicological and
controlled human exposure studies do not allow for an extensive examination of effect modifiers, the
use of animal models of disease and the study of individuals with underlying disease or genetic
polymorphisms do allow for comparisons between subgroups. Therefore, the results from these
studies, combined with those results obtained through stratified analyses in epidemiologic studies,
contribute to the overall weight of evidence for the increased susceptibility of specific populations to
an air pollutant (e.g., PM).
       This chapter discusses the  epidemiologic, controlled human exposure, and toxicological
studies evaluated in Chapters 6 and 7 that provide information on potentially susceptible
populations.  The  studies highlighted include only those studies that present stratified results  (e.g.,
males vs. females or <65 vs. > 65). This approach allowed for a  comparison between populations
exposed to similar PM concentrations and within the same study design. In addition, numerous
studies that focus on only one potentially susceptible population can provide supporting evidence on
whether a population is susceptible to PM exposure and are described in Chapters 6 and 7, but these
studies are not discussed in detail in this  chapter. Table 8-2 provides an overview of the factors
examined in  the current toxicological, controlled human exposure,  and epidemiologic literature and
the direction of the underlying evidence in determining whether a factor increases the susceptibility
of a population to PM-related health effects.
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Table 8-2.    Susceptibility factors evaluated.
                                       Factor                    Collective Evidence (+/-)2
                     Older Adults (> 65)                                        +
                     Children (<18)1                                          +
                     Pregnancy and Developmental Effects                           +*
                     Gender
                     Race/Ethnicity
                     Genetic factors
                     - Genetic polymorphisms                                    +
                     - Epigenetics
                     Cardiovascular Diseases                                    +
                     Respiratory Illnesses                                      +
                     Respiratory Contributions to Cardiovascular Effects
                     Diabetes                                              +*
                     Obesity                                               +*
                     Socioeconomic Status (SES)                                 +
                     Health Status (e.g., Nutrition)3                                 +*
                     1 The age range that defines a child varies from study to study. In some cases it is <21 years old while in others it is <18
                     years old (Firestone et al., 2007,192071). For the purposes of this exercise children are defined as those individuals <18
                     years old because the majority of epidemiologic studies consider individuals under the age of 18 children.
                     2 This column identifies whether the "collective" evidence from studies evaluated found that a specific factor increased (+)
                     or did not increase (-) a population's susceptiblity to PM exposure (i.e., PM exposure to all size fractions combined). In
                     instances where only a few studies were evaluated for a speicifc factor it was not possible to clearly assign a (+) or (-) as a
                     result the direction of the preliminary evidence is identified along with (*) to represent that more information is warranted.
                     3 These factors are surrogates of socioeconomic status and are discussed within this subsection of the chapter.
8.1.  Potentially Susceptible  Populations
8.1.1.  Lifestage

8.1.1.1.   OlderAdults
       Evidence for PM-related health effects in older adults spans epidemiologic, controlled human
exposure, and toxicological studies. The 2004 PM AQCD found evidence for increased risk of
cardiovascular effects in older adults  exposed to PM (U.S. EPA, 2004, 056905). Older adults
represent a potentially susceptible population due to the higher prevalence of pre-existing
cardiovascular and respiratory diseases found in this age range compared to younger age groups. The
increased susceptibility  in this population can primarily be attributed to the gradual decline in
physiological processes  as part of the aging process (U.S. EPA, 2006, 192082). Therefore, some
overlap exists between potentially susceptible older adults and the population that encompases
individuals with pre-existing diseases (Kan et al.,  2008, 156621). Epidemiologic studies that conduct
age stratified analyses primarily focus on the association between short-term exposure to PM and
cardiovascular morbidity, but additional studies have examined the association between PM and
respiratory morbidity and mortality.
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      In recent publications, the epidemiologic evidence for cardiovascular effects in older adults in
response to short-term exposure to PMi0_25 and PM25 is limited, but taken together with evidence
from studies of PMi0 (e.g., Larrieu et al., 2007, 093031; Le Tertre et al., 2002, 023746). supports the
increased risk of cardiovascular morbidity in older adults. Host et al. (2007, 155851) found an
increase in cardiovascular disease (CVD) hospital admissions in individuals >65 yr compared to all
ages for short-term exposure to both PMi0_2.5 and PM2 5.  Barnett et al. (2006, 089770) analyzed data
from several cities across Australia and New Zealand and found that the excess risk of
hospitalizations for cardiac diseases, congestive heart failure (CHF), ischemic heart disease (IHD),
myocardial infarction (MI), and all CVD was greater among patients aged > 65 yr as compared to
those individuals <65 years in response to short-term exposure to PM2.5. U.S.- and Canadian-based
studies that examined the association between short-term exposure to PM and cardiovascular
morbidity primarily found no evidence for increased risk among older  adults. Metzger et al. (2004,
044222) found no evidence of effect modification by age for cardiovascular outcomes and short-term
exposure to PM2 5 in Atlanta, Georgia, which is supported by the results from other studies that
focused on short-term exposure to PMi0 (Fung et al., 2005, 074322; Zanobetti and Schwartz, 2005,
088069). However, Pope et al. (2008, 191969) observed an increased risk of HF hospital  admissions
in older adults (i.e., > 65 yr) in Utah, but the study used  a 14-day lagged cumulative moving average
of PM2.5, which is much longer than the lags examined by the other U.S.-  and Canadian-based
studies. Although studies have not consistently found an association between short-term exposure to
PM and respiratory-related health effects in older adults, some studies  have reported an increase in
respiratory hospital admissions in individuals 65 years of age and older (e.g., Fung et al., 2005,
093262).
      Additional evidence for an increase in cardiovascular and respiratory effects among older
adults has been observed in controlled human exposure and dosimetry  studies. Devlin et al. (2003,
087348) found that older subjects exposed to PM2 5 concentrated ambient  particles (CAPs)
experienced significant decreases in heart rate variability (HRV) (both in time and frequency)
immediately following exposure, when compared to healthy young subjects. In addition,  Gong et al
(2004, 055628) reported that older subjects demonstrated significant decreases in HRV when
exposed to PM25 CAPs, but this study did not compare the response  in older subjects to those
elicited by young, healthy individuals. However, the study did find that healthy older adults were
more susceptible to decreases in HRV compared to those with an underlying health condition (i.e.,
chronic obstructive pulmonary disease [COPD]) in response to PM exposure (Gong et al., 2004,
055628). Dosimetry studies have shown a depression of PM25 and PMi0_2.5 clearance in all regions of
the respiratory tract with increasing age beyond young adulthood in humans and laboratory animals.
These results suggest that older  adults are also susceptible to PM-related respiratory health effects
(Section 4.3.4.1).
      Animal toxicological studies have attempted to characterize the relationship between age and
PM-related health effects through the development of models that mimic the physiological
conditions associated with older individuals. For example, Nadziejko et al. (2004, 055632) observed
arrhythmias in older, but not younger, rats exposed to PM2 5 CAPs. In addition, another study
(Tankersley et al., 2004, 094378) that used a mouse model of terminal  senescence demonstrated
altered baseline autonomic tone in response to carbon black exposure,  which may subsequently
affect the quality and severity of cardiovascular responses (Tankersley et al., 2007, 097910).
Reductions in cardiac fractional shortening and significant pulmonary  vascular congestion upon
exposure to carbon black were also reported in older mice (Tankersley et al., 2008, 157043). Overall,
these studies provide biological  plausibility for the increase in cardiovascular effects in older adults
observed in the  controlled human exposure and epidemiologic studies.
      Recent epidemiologic studies have also found that individuals >65 years of age are more
susceptible to all-cause (nonaccidental) mortality upon short-term exposure to both PM2 5 (Ostro et
al., 2006, 087991) and PM10 (Samoli et al., 2008, 188455; Zeka et al., 2006, 088749). which is
consistent with the findings of the 2004 PM AQCD. Of note are the results from Ostro et al. (2006,
087991) that reported a slight increase in mortality for older adults compared to all ages in single-
pollutant models, but a robust effect estimate in co-pollutant models with  gaseous pollutants
(i.e., PM25+CO and PM25+NO2). These results differ from those in the all ages model (i.e.,
attenuation of the effect estimate in co-pollutant models with  CO and NO2), which suggests that
older adults are more susceptible to PM exposures, even though the age-stratified effect estimates in
single-pollutant models did not significantly differ. Epidemiologic studies that examined  the
association between mortality and long-term exposure to PM  (i.e., PM25)  have found results
December 2009                                  8-4

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contradictory to those obtained in the short-term exposure studies. Villeneuve et al. (2002, 042576).
Naess et al. (2007, 090736) and Zeger et al. (2008, 191951) report evidence of differing PM2.5
relative risks by age, where risk declines with increasing age starting at age 60 until there is no
evidence of an association among persons > 85 yr.
      The evidence from epidemiologic, controlled human exposure, and toxicological studies that
focused on exposures to PM2.5,PMi0_2.5, and PMi0, provide coherence and biological plausibility for
the association between PM and cardiovascular morbidity in older adults. The clear pattern of
positive associations only being observed in epidemiologic studies conducted in non-U.S. locations
brings into question the influence of PM composition on health effects. However, the difference in
effects observed between U.S. and Canadian, and international studies could also be due to possible
differences in the identification of CVD-related morbidity and mortality between the studies
evaluated. Although most studies examined the effect of PM on CVD outcomes in older adults, the
additional evidence from epidemiologic studies that focus on respiratory morbidity and mortality in
response to short-term exposure to PM also indicate that older adults represent a susceptible
population. As the demographics of the U.S. population shift over the next 20 years with a larger
percentage of the population (i.e., 13% of the population in 2011 and a projected 20% in 2030)
encompassing individuals > 65 yr (U.S. Census, 2000, 157064). an increase in the number of
PM-related health effects (e.g., cardiovascular and respiratory morbidity, and mortality) in
individuals > 65 years of age could occur.


8.1.1.2.   Children

      Children have generally been considered more susceptible to PM exposure due to multiple
factors including more time spent outdoors, greater activity levels, exposures resulting in higher
doses per body weight and lung surface area, and the potential for irreversible effects on  the
developing lung (U.S. EPA, 2004, 056905). The 2004 PM AQCD found that studies which stratify
results by age typically report associations  between PM and respiratory-related health effects in
children, specifically asthma (U.S. EPA,  2004, 056905). Of the  recent epidemiologic studies
evaluated, only a few have examined the association between PMi0_2.5 and PM2.5 and respiratory
effects in children. Mar et al. (2004, 057309) found increased respiratory effects (e.g., wheeze,
cough, lower respiratory symptoms) in children 7-12 years of age compared to individuals 20-51
years of age in response to exposure to both PMi0_2.5 and PM2.5 in Spokane, Washingon. In addition,
Host et al. (2007,  155851) found an increase in respiratory-related hospital admissions with short-
term exposure to PMi0_2.s among children ages 0-14 yr in 6 French cities. An  examination of studies
that also focused on PMi0 provide additional support for PM-induced respiratory effects in children
(Mar et al., 2004, 057309; Peel et al., 2005, 056305). A recent toxicological study provides
biological plausibility for the increase in PM-related respiratory effects in children  observed in the
epidemiologic studies. Mauad et al. (2008, 156743) using both prenatal and postnatal mice exposed
to ambient PM2.5 in a "polluted chamber" found evidence for changes in lung function and
pulmonary injury (e.g., incomplete alveolarization). Additionally, Pinkerton et al. (2004,  087465;
2008, 190471) found evidence suggesting that the developing lung is more susceptible to PM by
demonstrating that neonatal rats exposed to iron-soot PM had a reduction in cell proliferation in the
lung. Overall, the evidence from epidemiologic studies that have examined the health effects
associated with all size fractions of PM and toxicological studies that have examined individual  PM
components provide additional support to the hypothesis that children are more susceptible to
respiratory effects from exposure to PM.


8.1.2.  Pregnancy and Developmental Effects

      While the majority of the  literature focuses on epidemiologic studies that examine the
potential health effects (e.g., low birth weight, growth restriction) attributed to in utero exposure to
PM (see Section 7.4), it is unclear if the health effects observed are due to soluble fractions of PM
that cross the placenta or physiological alterations in the pregnant woman. In the case of exposure to
PM, adverse health effects in the offspring could be mediated by potentially greater susceptibility in
the pregnant woman. For example, an inflammatory response leads to differential activation of
multiple genes involved in immune response and regulation, cell metabolism, and proliferation all of
which can lead to health effects  in the developing fetus (Fedulov et al., 2008, 097482). Toxicological
December 2009                                  8-5

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studies have recently examined whether exposure to air pollutants during pregnancy leads to
increased allergic susceptibility in the offspring. Fedulov et al. (2008, 097482) used an animal model
to examine the effect of diesel exhaust particles (DEPs) along with an immunologically "inert"
particle (TiO2) on pregnant mice. The authors found that pregnant mice exhibited a local and
systemic inflammatory response when exposed to either DEP or TiO2, which was not observed in
control, non-pregnant mice. In addition, the offspring of exposed pregnant mice developed AHR and
allergic inflammation. This study suggests that exposure to PM2 5, and even relatively inert particles,
during pregnancy can potentially lead to increased allergic susceptibility in offspring and
subsequently the development of asthma.


8.1.3.  Gender

      The 2004 PM AQCD did not find consistent evidence for a difference in health effects by
gender. However, there appeared to be gender differences in the localization of particles when
deposited in the respiratory tract and the deposition rate due to differences in body size, conductive
airway size, and ventilatory parameters (U.S. EPA, 2004, 056905). For example, females have
proportionally smaller airways and slightly greater airway reactivity than males (Yunginger et al.,
1992. 192074).
      Few recent epidemiologic studies have conducted gender-stratified analyses when examining
the association between either short- or long-term exposure to PMi0_2.5 or PM2.5. Similar to the
studies evaluated in the 2004 PM AQCD,  the current literature has not found a consistent pattern of
associations by gender for any health outcome.  Pope et al. (2006, 091246) observed a slightly larger,
non-significant, association between short-term exposure to PM2.5 and daily hospital admission for
acute IHD events  in males. An examination of gender-specific effects by both Ostro et  al. (2006,
087991) and Franklin et al. (2007, 091257) found conflicting associations by gender for multiple
cause-specific mortality outcomes. The inconsistency in associations between males and females is
further highlighted in studies that examined the health effects associated with long-term exposure to
PMio_2.5 and PM2 5. Chen et al. (2005, 087942) found larger effects in females for congestive heart
disease (CHD) mortality upon long-term exposure to PMi0_2.5 in three California cities.  Naess et al.
(2007, 090736). also observed slightly larger effect estimates in females for CVD and lung cancer
mortality upon long-term exposure to PM2 5, but for COPD mortality the greatest association was
found in males.
      The majority of the epidemiologic studies that examined the association between exposure to
PM and gender focused on exposure to PMi0. Although most of these studies do not attribute  the
association to specific size fractions (i.e., PMi0_2.5 or PM2 5) or provide insight as to whether one size
fraction may be driving the observed effect, the studies of PMi0 provide further support that gender
does not appear to differentially affect PM-related health outcomes. Neither Zanobetti and Schwartz
(2005, 088069) nor Wellenius et al. (2006, 088748) found gender to be a significant effect modifier
of the risk estimates associated with short-term  exposure to PMi0 and cardiovascular hospital
admissions. These results are consistent with those found in other studies that examined the
association between short-term exposure to PMi0 and both cardiovascular and respiratory hospital
admissions (Luginaah et al., 2005, 057327; Middleton et al., 2008, 156760). Additional studies that
examined the effects of short-term and long-term exposure to PMi0 on respiratory morbidity and
mortality (Boezen et al., 2005, 087396; Chen et al., 2005, 087942; Zanobetti and Schwartz, 2005,
088069; Zeka et al., 2006, 088749) found  results that are consistent with those reported in studies of
PMio_2.5 and PM25 (i.e., gender is not likely to be an effect modifier).
      Although human clinical studies are not typically powered to detect differences in response
between males and females, one study did report significantly greater decreases in blood monocytes,
basophils, and eosinophils in females compared to males following controlled exposures to UF EC
(Frampton et al., 2006, 088665). Overall, the evidence from primarily epidemiologic studies that
examined the association between short- and long-term exposure to PMi0_2.5 and PM2 5, along  with
the supporting evidence from PMi0 studies, further confirms that although differences in dosimetry
exist between males and females, neither gender consistently exhibits a higher disposition for PM-
related health effects.
December 2009                                  8-6

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8.1.4.  Race/Ethnicity

      The 2004 PM AQCD (U.S. EPA, 2004, 056905) did not evaluate the potential susceptibility of
individuals of different races and ethnicities to PM exposure. The results from epidemiologic studies
evaluated in this review that examined the potential effect modification of the PM-morbidity and -
mortality relationships by race and ethnicity varied depending on the study location. In an analysis of
the PM2.5-mortality relationship, Ostro et al. (2006, 087991) stratified the association by race and
ethnicity, and observed a positive and marginally significant effect for whites and Hispanics, but not
for blacks, in response to short-term exposure to PM2.5 in 9 California counties. An additional
analysis performed by Ostro et al. (2008, 097971) in 6 California counties using PM2.5 and various
PM2.5 components, also found a significant association between mortality, specifically  cardiovascular
mortality, and Hispanic ethnicity (Ostro et al., 2008,  097971). It should be noted that neither study,
Ostro et al. (2006, 087991) nor Ostro et al. (2008, 097971). controlled for potential confounders
(e.g., SES factors and location of residence) of the association observed between PM25 exposure and
Hispanic ethnicity. As a result, Ostro et al (2008, 097971) speculated that the increased PM2 5-
mortality risks observed for Hispanics could be due to a variety of factors including, higher rates of:
non-high school graduates, obesity, no leisure-time activity, and alcohol consumption within the
Hispanic population in California. Additional evidence for the potential susceptibility of individuals
by race and ethnicity were derived from studies on the health effects associated with short-term
exposure to PMi0. Wellenius et al. (2006, 088748) observed that race (i.e., white vs. other)  did not
significantly modify the association between short-term exposure to PMi0and CHF hospital
admissions. Additionally, Zeka et al. (2006, 088749) did not observe any difference in  mortality
effect estimates when stratifying by  race (i.e., black and white) upon short-term exposure to PMi0.
To date, dosimetry studies have not extensively examined differences in particle deposition between
races or ethnicities to confirm the epidemiologic findings. Although not extensively analyzed,
toxicological studies have  examined PM responses in different mouse and rat strains, and reported
greater CV effects  (Kodavanti et al., 2003, 051325; Tankersley et al., 2007, 097910) and
compromised host defense (Ohtsuka et al., 2000,  004409) for some strains. These studies provide
some support, in terms of biological plausibility, for  differences in PM-induced health  effects by race
or ethnicity. However, it is unclear how the difference in the response to PM in different mouse or rat
strains extrapolates to PM-induced differences between races or ethnicities.  Overall, the results from
the studies that examined the  potential effect modification of PM associations by race and ethnicity
provide some evidence for increased risk of mortality in Hispanics upon short-term exposure to
PM2 5. However, the evidence for this association is derived from two studies conducted in
California, and it is unclear if the studies adequately  controlled for potential confounders. Additional
studies conducted in other locations that stratify results by ethnicity have not yet been conducted to
substantiate these results.


8.1.5.  Gene-Environment Interaction

      A consensus now exists that gene-environment interactions merit serious consideration when
examining the relationship between  ambient exposures to air pollutants and the development of
health effects (Gilliland et al., 1999, 155792: Kauffmann et al., 2004, 090968). These potential
interactions were not evaluated in the 2004 PM AQCD. Inter-individual variation in human
responses to air pollutants  suggests that some populations are at increased risk of detrimental effects
due to pollutant exposure,  and it has become clear that the genetic makeup of an individual can
increase their susceptibility (Kleeberger and Ohtsuka, 2005,  130489). Gene-environment
interactions can result in health effects due to: genetic polymorphisms, which result in  the lack of a
protein or a change that makes a functionally important protein dysfunctional; or genetic damage in
response to an exposure which potentially leads to a  health response (e.g., formation of benzo [a]
pyrene DNA adducts in response to PM exposure). In this review, the majority of studies examine
gene-environment interactions due to genetic polymorphisms. In order to establish useful links
between polymorphisms in candidate genes and adverse health effects, several criteria  must be
satisfied: the product of the candidate gene must be significantly involved in the pathogenesis of the
adverse effect of interest; and polymorphisms in the  gene must produce a functional change in either
the protein product or in the level of expression of the protein (U.S. EPA, 2008, 157075). Further, the
issue of confounding by other environmental exposures must be carefully considered.
December 2009                                  8-7

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      It has been hypothesized that the cardiovascular and respiratory health effects that occur in
response to short-term PM exposure are mediated by oxidative stress (see Section 5.1.1). Research
has examined this hypothesis by primarily focusing on the glutathione-S transferase (GST) genes
because they have common, functionally important polymorphic alleles that significantly affect
antioxidant defense function in the lung, and approximately half of the white population has a
polymorphic null allele, resulting a large potential study population (Schwartz et al., 2005, 086296).
Exposure to free radicals and oxidants in air pollution leads to a cascade of events, which can result
in a reduction in glutathione (GSH), and an increase in the transcription of GSTs. Individuals with
genotypes that result in reduced or absent enzymatic activity are likely to have reduced antioxidant
defenses and potentially increased susceptibility to inhaled oxidants and free radicals.
      Numerous studies have examined the role of genetic polymorphisms  on PM-related
cardiovascular health effects using the Normative Aging Study cohort. Schwartz et al.  (2005,
086296) and Chahine et al. (2007, 156327) found that individuals with null GSTM1 alleles had a
larger decrease in HRV upon short-term exposure to PM2.5 compared to individuals with at least one
allele. Polymorphisms in the HO-1 promoter resulted in lowered HRV upon short-term exposure to
PM2 5 in individuals with the long repeat polymorphism compared to those individuals with the short
repeat polymorphism (Chahine et al.,  2007, 156327). In addition, Schneider et al. (2008, 191985)
found that diabetic individuals with null GSTM1 alleles had larger decrements in FMD (i.e., flow-
mediated dialation of the brachial artery), suggesting alterations in endothelial function. A controlled
human exposure study (Gilliland et al., 2004, 156471) also examined whether genetic
polymorphisms increase the susceptibility of individuals to respiratory morbidity in response to PM
exposure. Gilliland et al. (2004, 156471) examined the effect of allergens and DEPs on individuals
with either null genotypes for GSTM1 and GSTT1 or GSTP1 codon 105 variants. The authors found
that individuals with the GSTM1 null or the GSTP1 1105 wildtype genotypes were more susceptible
to allergic inflammation upon exposure to allergen and DEPs. Additional genes  within the GST
pathway have also  been examined (e.g., NQO1), but the sample sizes are relatively small, which
prohibits the analysis of the potential  effect modification of PM-related health effects by these genes
(e.g., Schneider et al., 2008, 191985).
      The interaction between GST genes and PM exposure has recently been extended to studies
that examined the effect of PM exposure on birth outcomes. A recent study  (Suh et al., 2008,
192077) that examined the effect of high PM10 exposures during the third trimester of pregnancy on
the risk of preterm delivery, found that women with the GSTM1 null genotype were at an increased
risk of preterm birth. When examining the interaction between high PMi0 concentrations during the
third trimester of pregnancy and the presence of the GSTM1 null genotype  on the risk of preterm
delivery, there was evidence for a synergistic gene-environment interaction in pregnant women.  This
effect could occur due to oxidative stress induced by metals contained in PMi0,  and subsequently
could be modified by polymorphisms of the GSTM1 gene. This oxidative stress causes oxidative
DNA damage in fetal tissues, which may lead to preterm delivery via a reduction in placental blood
flow.
      An examination of other genes  outside the GST pathway have also been conducted to
determine if specific polymorphisms increase the susceptibility of individuals to PM. Baccarelli et al.
(2008, 157984) in the Normative Aging Study observed that individuals with polymorphisms in
MTHFR (C677T methylenetetrahydrofolate reductase), an alteration associated with reduced
enzyme activity, and cSHMT (cytoplasmic serine hydroxymethyltransferase) (i.e., [CT/TT] MTHFR
and [CC] cSHMT genotypes), alterations associated with higher homocysteine levels, have a
reduction in SDNN, upon exposure to PM2.5. Peters et al. (2009, 191992) examined single nucleotide
polymorphisms (SNPs) in the fibrinogen gene in myocardial infarction survivors to assess whether
exposure to PMi0 altered steady state  levels of fibrinogen, which has been implicated in promoting
atherothrombosis. The authors found that individuals with single nucleotide polymorphisms (SNPs)
in the fibrinogen gene have higher baseline fibrinogen levels which when combined with the
inflammatory effects (i.e., increased fibrinogen levels) associated with exposure to PM could
increase their risk of PM-related cardiovascular health effects. These results taken together suggest
that individuals with null alleles or specific polymorphisms in genes that mediate the antioxidant
response to oxidative stress, regulate enzyme activity, or regulate levels of procoagulants are  more
susceptible to PM.  However, in some cases genetic polymorphisms may actually reduce an
individual's susceptibility to PM-related health effects. For example, Park et al.  (2006, 091245)
found that individuals with two hemochromatosis (HFE) polymorphisms (C282Y and H63D), which
result in an increase in iron uptake, had smaller reductions in HRV upon exposure to PM2.5. This
December 2009                                  8-8

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effect could possibly be due to the reduction in free iron that enters oxidation-reduction (redox)
reactions and the subsequent reduction in reactive oxygen species (ROS).
      More recently, studies have begun to focus on epigenetic effects associated with PM exposure
(i.e., the effect of PM on DNA methylation) due to the fact that DNA methylation can result in gene
alterations. The limited number of epidemiologic studies that examined epigenetic effects have
found some evidence that long-term exposure to PM2 5 and PMi0 can influence DNA methylation
(Baccarelli et al, 2009, 188183; Tarantini et al.,  2009, 192010). Additionally, a toxicological study
found some evidence of hypermethylation of spermatogonial stem cells in response to the PM
component of ambient urban air (Yauk et al.,  2008,  157164). Although epigenetic effects have been
observed in response to PM exposure in some studies additional research is needed to more
accurately characterize these associations.
      Overall, the evidence suggests that specific genetic polymorphisms can potentially increase
the susceptibility of an individual to PM exposure, but protective polymorphisms also exist, which
may diminish the health effects attributed to PM exposure in some individuals. In addition, the
studies that examine genetic polymorphisms or epigenetics can potentially provide additional
information that can aid in identifying the specific pathways and mechanisms by which PM initiates
health effects.


8.1.6.  Pre-Existing Disease

      In 2004, the National Research Council (NRC) published a report that emphasized the need to
evaluate the effect of air pollution on susceptible populations, including those with respiratory
illnesses and cardiovascular diseases (NRC, 2004, 156814). The 2004 PM AQCD included
epidemiologic evidence suggesting that individuals  with pre-existing heart and lung diseases, as well
as diabetes may be more susceptible to PM exposure.  In addition, toxicological studies that used
animal models of cardiopulmonary diseases and heightened allergic sensitivity found evidence of
enhanced susceptibility. More recent epidemiologic and human clinical studies have directly
examined the effect of PM on individuals with pre-existing diseases and toxicological studies have
employed disease models to identify whether exposure to PM disproportionately effects certain
populations.


8.1.6.1.   Cardiovascular Diseases

      The potential effect of underlying cardiovascular diseases on PM-related health responses has
been examined using epidemiologic studies that stratify  effect estimates by underlying conditions or
secondary diagnoses, and toxicological  studies that  use animal models to mimic the physiological
conditions associated with various cardiovascular diseases (e.g., MI, ischemia, and atherosclerosis).
A limited number of controlled human exposure studies  have also examined the potential
relationship between CVD and exposure to PM in individuals with underlying cardiovascular
conditions, but these studies have provided somewhat inconsistent evidence for these associations.
      The majority of the epidemiologic literature that examined the association between short-term
exposure to PM and cardiovascular outcomes focuses on cardiovascular-related hospital admissions
and emergency department (ED)  visits.  Hypertension is the pre-existing condition that has been
considered to the greatest extent when examining the association between short-term exposure to PM
and cardiovascular-related HAs and ED visits. Pope et al. (2006, 091246) found no evidence of
effect modification of the IHD ED visit association  with PM2.5in individuals  with secondary
hypertension in Utah. This is consistent with the results of both Wellenius et al. (2006, 088748) in 7
U.S. cities and Lee et al. (2008, 192076) in Taipei, which found that hypertension did not modify the
association between PM10 and cardiovascular-related health outcomes. These results differ from
those presented by  Peel et al. (2007, 090442). in Atlanta, which observed that exposure to PMi0
resulted in an increase in ED visits for arrhythmias and CHF in individuals with underlying
hypertension. An additional study conducted by  Park et al. (2005, 057331) in Boston found that
underlying hypertension increased associations between HRV, specifically a reduction in the HF
parameter, and short-term exposure to PM2.5.
      Park et al. (2005, 057331). in the  analysis mentioned above, examined other underlying
cardiovascular conditions and found associations between PM2.5 and HRV in individuals with
pre-existing IHD. In a toxicological study, Wellenius et al. (2003, 055691) examined the effects of
December 2009                                  8-9

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PM2.5 CAPs exposure on induced myocardial ischemia in dogs, which mimics the effects associated
with IHD. The authors found that exposure to PM2.5 prior to the induced ischemia increased
ST-segment elevation, indicating greater ischemia than air-exposed animals (Wellenius et al., 2003,
055691). A follow-up study implicated impaired myocardial blood flow in the response (Bartoli et
al., 2009, 179904).
      Additional studies examined the effects of PM on  cardiac function in individuals with
dysrhythmia. Peel et al. (2007, 090442) observed some evidence for an increase in ED visits for IHD
for individuals with secondary dysrhythmia and PMi0 exposure. However, when examining CHF
hospital admissions in 7 U.S. cities, Wellenius et al. (2006, 088748) found no evidence for effect
modification of PMi0 exposure in individuals with secondary dysrhythmia.
      Limited evidence is available from epidemiologic  studies that examined other pre-existing
cardiovascular conditions, such as CHF and MI. Pope et  al. (2006, 091246) observed an increase in
hospital admissions for acute IHD in individuals with underlying CHF upon short-term exposure to
PM2.5. However, Peel et al. (2007, 090442) did not find that underlying CHF contributed to an
increase in the association between IHD ED  visits and short-term exposure to PMi0. Zanobetti and
Schwartz (2005, 088069) also examined the potential effect modification of the association between
PMio and cardiovascular-related health effects in individuals with CHF, but used MI hospital
admissions as the outcome of interest. Underlying CHF was not found to increase MI hospital
admissions for exposure to PMi0 in the cohort of more than 300,000 hospital admissions.
      Wellenius et al. (2006, 088748) examined the effect of previous diagnoses of acute MI on the
association between CHF hospital admissions and short-term exposure to PMi0 in 7 U.S. cities. In
this study, Wellenius et al. (2006, 088748) found no evidence of effect modification of the
relationship between PMi0 and CHF hospital admissions by previous acute MI. Toxicological studies
have provided additional evidence for the cardiovascular health effects associated with exposure to
PM in individuals with underlying MI. Anselme et al. (2007, 097084) and Wellenius et al. (2006,
156152) examined the arrhythmic effects of PM on rats that experienced an MI using two different
models. Wellenius et al. (2006, 156152) used a post-myocardium sensitivity model (acute MI) and
observed that exposure to PM2 5  CAPs decreased ventricular premature beats and spontaneous
supraventricular ectopic beats. In contrast, the MI model of chronic heart failure (i.e., rats that
experienced an MI 3 mo prior to exposure), demonstrated a prominent increase in the incidence of
premature ventricular contraction when exposed to DE (Anselme et al., 2007, 097084). The
discrepancy in effects observed between studies could be due to differences in the MI model or the
PM exposure (i.e., CAPs vs. DE).
      Additional toxicological studies examined the association between PM and pre-existing
cardiovascular diseases using amurine model of atherosclerosis (ApoE~'~ mouse). For example,
Campen et al. (2005, 083977: 2006, 096879) examined the heart rate and ECG effects of acute
exposure to PM on ApoE"'" mice. With DE, dramatic bradycardia and T-wave depression were
observed that were attributable to the gases (Campen et al., 2005,  083977), while whole gasoline
emissions induced T-wave alterations that required particles (Campen et al., 2006, 096879).
However, these studies along with others that used this mouse model (see Section 6.2 and 7.2) did
not compare the effects observed with the ApoE"" mouse to other non-diseased mouse models, so it is
unclear if the responses would differ if other strains were used in the  same experimental protocol.
      Controlled human exposure studies that examined the effect of pre-existing diseases on
cardiovascular outcomes with exposure to PM are less consistent and difficult to interpret in the
context of the results from the epidemiologic and toxicological studies. Mills et al. (2007, 091206;
2008, 156766) investigated the effects of dilute DE, or fine and ultrafine CAPs, respectively, on
subjects with coronary artery disease and prior MI. Exposure to dilute DE was  found to promote
exercise-induced ST-segment changes indicating myocardial ischemia, as well  as inhibit endogenous
fibrinolytic capacity (Mills et al., 2007, 091206). The physiological responses observed in Mills et
al. (2007, 091206) provides a measure of coherency with the cardiovascular effects observed in
epidemiologic studies, including increases in hospital admissions and ED visits for IHD and stroke
associated with exposure to PM. An examination of fine  and ultrafine CAPs that were low in
combustion derived particles, were not found to exhibit any significant effects on vascular function
(Mills et al., 2008,  156766). Routledge et al.  (2006, 088674) reported no change in HRV in a group
of adults with coronary artery disease following exposure to ultrafine carbon particles,  which may be
explained in part by the use of medication (beta blockers) among the majority of the subjects.
Although the epidemiologic studies did not examine potential effect modification of pre-existing
cardiovascular conditions on effects associated with long-term exposure to PM, a few
December 2009                                 8-10

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toxicological studies exposed animals with underlying cardiovascular conditions to PM for
months. In studies that focused on the cardiovascular effects following subchronic exposure to
PM in ApoE"A mice, relatively consistent physiological effects were observed across studies.
Araujo et al. (2008,  156222) exposed mice to ultrafme CAPs and observed enhanced size of
early atherosclerotic lesions. Similarly, Chen and Nadziejko (2005, 087219) and Sun et al. (2005,
087952: 2008, 157033) exposed mice to PM2.5 CAPs with the same results. An additional
long-term exposure  study observed a decreasing trend in heart rate, physical activity, and
temperature along with biphasic responses in HRV (SDNN and rMSSD) upon exposure to CAPs
(Chen  and Hwang, 2005, 087218).
      While the majority of the literature examines the potential modification of the association
between PM and non-fatal cardiovascular health effects, a few new studies have also examined
effect modification in mortality associations. Zeka et al. (2006, 088749) found an increase in risk
estimates for associations between PMi0 and mortality in individuals with underlying stroke, while
Bateson et al. (2004, 086244) found evidence for effect modification of the PM-mortality association
in individuals with CHF.
      Collectively, the  evidence from epidemiologic and toxicological, and to a lesser extent,
controlled human exposure studies indicates that individuals with underlying cardiovascular diseases
are susceptible to PM exposure. Although the evidence for some outcomes was inconsistent across
epidemiologic and toxicological studies, this could be due to a variety of issues including the PM
size fraction used in the study along with the study  location. Even with these caveats, a large
proportion of the U.S. population has been diagnosed with cardiovascular diseases (i.e.,
approximately 51.6 million people with hypertension, 24.1 million with heart disease, and 14.1
million with coronary heart disease [see Table 8-3]), and therefore represents a large population that
is potentially more susceptible to PM exposure than the general population.


Table 8-3.    Percent of the U.S. population with respiratory diseases, cardiovascular diseases, and
             diabetes.
                                             Age
                                                            Regional
                          Adults (18+)*
                     18-44    45-64
65-74
75+
NE
MW
W
   Chronic Condition/
       Disease
Number (x 1(T
RESPIRATORY DISEASES
Asthma*
                          24.2
                                    11.0
                                            11.5
                                                    10.5
                                                            11.7
                                                                    9.3
                                                                          11.7
                                                                                 11.5
                                                                                       10.5   10.8
Asthma (<18yrs)
                          6.8*
                                    9.3*
COPD
Chronic bronchitis
                           9.5
                                     4.3
                                            2.9
                                                    5.5
                                                            5.6
                                                                    6.7
                                                                          3.8
                                                                                 4.4
                                                                                        4.9
                                                                                              3.5
Emphysema
                           4.1
                                            0.3
                                                    2.4
                                                            5.0
                                                                    6.4
                                                                          1.4
                                                                                 2.3
                                                                                        1.9
                                                                                              1.6
CARDIOVASCULAR DISEASES
All heart disease
                          24.1
                                    10.9
                                            3.6
                                                    12.3
                                                            26.1
                                                                   36.3
                                                                          10.8
                                                                                 12.7
                                                                                       10.9
                                                                                              9.2
Coronary heart disease
                          14.1
                                     6.4
                                            0.9
                                                    7.2
                                                            18.4
                                                                   25.5
                                                                          6.4
                                                                                 7.6
                                                                                        6.6
                                                                                              4.7
Hypertension
                          51.6
                                    23.4
                                            77
                                                    32.4
                                                            52.7
                                                                   53.5
                                                                          22.2
                                                                                23.7
                                                                                       25.3
                                                                                             20.6
Stroke
                           5.6
                                     2.6
                                            0.5
                                                    2.4
                                                            7.6
                                                                   11.2
                                                                          2.1
                                                                                 2.8
                                                                                        2.9
                                                                                              2.2
Diabetes
                          17.1
                                     7.8
                                            2.6
                                                    10.4
                                                            18.2
                                                                   17.9
                                                                          7.2
                                                                                        8.0
                                                                                              7.4
* All data for adults except asthma prevalence data for children under 18 years of age, from CDC (2008,156324: 2008,156325). For adults prevalence data based off adults
responding to "ever told had asthma."

                                           Source: Data from Pleis and Lethbridge-Qejku (2007,1568751: CDC (2008,156324: 2008,1563251.
December 2009
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8.1.6.2.   Respiratory Illnesses

      Investigators have examined the effect of pre-existing respiratory illnesses on multiple health
outcomes (e.g., mortality, asthma symptoms, CHF) in response to exposure to ambient levels of PM.
Animal models have been developed and/or human clinical studies conducted to examine the
possible PM effects on pre-existing respiratory conditions in a controlled setting.
      Epidemiologic studies have examined the effect of short-term exposure to PM on the
respiratory health of asthmatic individuals measuring a variety of respiratory outcomes. Asthmatic
individuals were found to have an increase in medication use (Rabinovitch et al., 2006, 088031).
respiratory symptoms (i.e., asthma symptoms, cough, shortness of breath, and chest tightness) (Gent
et al., 2003, 052885). and asthma symptoms (Delfino et al., 2002, 093740; 2003, 050460) with short-
term exposure to PM2.5; and morning symptoms (Mortimer et al., 2002, 030281) and asthma attacks
(Desqueyroux et al., 2002, 026052) with short-term exposure to PMi0.
      Toxicological studies that have used ovalbumin-induced allergic airway disease models
provide evidence which supports the findings of the epidemiologic literature. Morishita et al. (2004,
087979) used this model to assess the health effects of PM2.5 components. In response to short-term
exposure to CAPs from Detroit, an area with pediatric asthma rates three times the national average,
rats with allergic airway disease were found to preferentially retain PM derived from identified local
combustion sources in association with eosinophil influx and BALF protein content after an acute
exposure (Morishita et al., 2004, 087979). These findings suggest that individuals with allergic
airways conditions are more susceptible to allergic airways responses upon exposure to PM2.5, which
may be partially attributed to increased pulmonary deposition and localization of particles in the
respiratory tract (Morishita et al., 2004, 087979). An additional study (Heidenfelder et al., 2009,
190026) examined whether genes  are differentially expressed upon exposure to PM. They found that
exposure to CAPs increased the expression of genes associated with inflammation and airway
remodeling in rats with allergic airway disease. Although the evidence is much more limited, not all
of the toxicological studies evaluated that examined the effect of underlying respiratory conditions
on PM-related respiratory morbidity focused on allergic airways disease. Using an animal model of
emphysema (i.e., papain-treated mice), Lopes et al. (2009, 190430) found that papain-treated mice
exposed to urban ambient PM demonstrated a statistically significant increase in mean linear
intercept, a measure of airspace enlargement, compared to saline-treated controls exposed to filtered
air. These results provide preliminary evidence, which suggests that non-allergic respiratory
morbidities may also increase the susceptibility of an individual to PM-related respiratory effects.
      The results from the epidemiologic and toxicological studies that focused on  underlying
allergic airways disease is supported by a series of controlled human exposure studies which have
shown that exposure to DEPs increases the allergic inflammatory response in atopic individuals
(Bastain et al., 2003, 098690; Diaz-Sanchez et al., 1997, 051247; Nordenhall et al., 2001, 025185).
However, not all controlled human exposure studies have found evidence for differences between the
respiratory effects exhibited by healthy and asthmatic individuals. Studies by Gong et al. (2003,
042106; 2004, 055628; Gong et al., 2008, 156483) reported that healthy and asthmatic subjects
exposed to coarse, fine and ultrafine CAPs, exhibited similar respiratory responses. However, it
should be noted that these studies excluded moderate and severe asthmatics that would be expected
to show increased susceptibility to PM exposure.
      In  addition to examining the association between exposure to PM and respiratory effects in
asthmatics, some studies examined whether individuals with COPD represent a potentially
susceptible population. Desqueyroux et al. (2002, 026052) did not observe an increase in the
exacerbation1 of COPD in response to short-term exposure to PM2 5. However, studies that  examined
the effect of PM on lung function in individuals with COPD (Lagorio et al., 2006, 089800;  Trenga et
al., 2006, 155209) observed declines in FEVi, and FEVi and FVC, respectively in response to PMi0
and/or PM25. Silkoff et al. (2005, 087471) observed associations between PMi0 and a reduction in
FEVi and PM25 and a reduction in PEF, in those with COPD, but only during one winter of the
analysis.  Only one controlled human exposure study examined the effects of PM on COPD subjects
and found no significant difference in respiratory effects between healthy and individuals with
COPD upon exposure to PM2.5 CAPs (Gong et al., 2004, 055628). On the other hand the results from
dosimetry studies have shown that COPD patients have increased dose rates and impaired
1 Desqueyroux et al. (2002, 026052) defined a COPD exacerbation as (a) decrease in "vesicular" breath sound, (b) bronchial obstruction,
 (c) tachycardia or arrhythmia, or (d) cyanosis.
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mucociliary clearance relative to age matched healthy subjects, suggesting that individuals with
COPD are potentially at a greater risk of PM-related health effects (Sections 4.2.4.5 and 4.3.4.3).
      A few of the epidemiologic studies examined the effect of underlying respiratory illnesses on
the association between short- and long-term exposure to PM and mortality. Using different
pre-existing respiratory illnesses, Zeka et al. (2006, 088749) and De Leon et al. (2003, 055688)
found that short-term exposure to PMi0 increased the risk of nonaccidental mortality for pneumonia
and circulatory mortality for all respiratory illnesses, respectively. Additionally, Zanobetti et al.
(2008, 156177) observed an association between long-term exposure to PMi0 and mortality in
individuals that had previously been hospitalized for COPD. Although these studies do not examine
additional size fractions of PM, together they highlight the potential effect of underlying respiratory
illnesses on the PM-mortality relationship.
      Overall, the epidemiologic, controlled human exposure, and toxicological studies evaluated
provide biological plausibility for the increased health effects observed in epidemiologic studies
among asthmatic individuals in response to PM exposure. Although, the evidence from studies that
examined associations between PM and health effects in individuals with COPD is inconsistent,
taken together individuals with  COPD and asthma represent a large percent of the U.S. population
(~45 million people), which may be more susceptible to PM-related health effects (Table 8-3).


8.1.6.3.   Respiratory Contributions to Cardiovascular Effects

      Although the majority of health effects observed in individuals with pre-existing respiratory
illnesses were associated with respiratory illness exacerbations, studies also examined whether
underlying respiratory illnesses can lead to cardiovascular effects in response to PM exposure.
Controlled human exposure and toxicological studies have also observed some cardiovascular effects
in individuals with pre-existing respiratory illnesses. Gong et al. (2003, 042106) observed acute
responses in the cardiovascular system and systemic circulation among asthmatic individuals after
exposure to PM2.5 CAPs. However, respiratory disease has not consistently been observed to affect
cardiovascular response in controlled human exposure studies. In a toxicological study, Batalha et al.
(2002, 088109). using a chronic bronchitis animal model, found that the pulmonary artery
lumen-to-wall ratio was decreased in rats exposed to PM2.5 CAPs, although the induced bronchitis
didn't seem to affect the response. The majority of epidemiologic studies that examined whether
underlying respiratory illnesses contributed to the manifestation of PM-related cardiovascular
hospital admission or ED visits, did not report increases in effects for a variety of cardiovascular
outcomes (e.g., IHD, arrhythmias, CHF, MI) for individuals with underlying respiratory infection
(Wellenius et al., 2006, 088748). pneumonia (Zanobetti and Schwartz, 2005, 088069). or COPD
(Peel et al., 2007, 090442; Wellenius et al., 2005, 087483). However, Yeatts et al. (2007, 091266). in
a panel study, found evidence for cardiovascular effects, specifically reductions in HRV parameters,
in asthmatic adults upon short-term exposure to PMi0_2.5. It must be noted that most of the
aforementioned epidemiologic studies focused on exposure to PMi0, and, therefore, it is unclear how
these results compare to those found in  the controlled human exposure and toxicological studies that
focused on exposure to PM2.5 (e.g., CAPs). Thus, it is unclear if individuals with underlying
respiratory illnesses represent a population that is potentially  susceptible to PM-related
cardiovascular effects.


8.1.6.4.   Diabetes and Obesity

      It has been hypothesized that the  systemic inflammatory cascade leads to an increase in
cardiovascular risk (Dubowsky  et al., 2006,  088750). As a result, individuals with conditions linked
to chronic inflammation (i.e., diabetes and obesity), have been examined to determine whether
diabetes or obesity facilitate the manifestation of PM-mediated health effects, and, therefore,
represent a potentially susceptible population.
      Epidemiologic studies have examined whether diabetes modifies the association between
cardiovascular health effects and PM exposure, but these studies have primarily focused on short-
term exposure to PMi0. Time-series studies have provided evidence through an examination of
hospital admission and ED  visits and mortality, which suggests an increase in health effects in
diabetic individuals in response to PM exposure. Multicity studies have found upwards of 75%
greater risk of hospitalization for cardiac diseases in individuals with diabetes upon exposure to
     (Zanobetti and Schwartz, 2002, 034821). Studies conducted in Atlanta, Georgia have also
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found increased risk for cardiovascular-related ED visits in diabetics, specifically for IHD,
arrhythmias, and CHF (Peel et al., 2007, 090442). Additional studies found some evidence that
individuals with diabetes are at increased risk of mortality upon exposure to PMi0 (Zeka et al., 2006,
088749) and PM2.5 (Goldberg et al., 2006, 088641). However, some studies (both multicity and
single-city) have not observed a modification of the risk of cardiovascular ED visits and hospital
admissions in response to exposure to PMi0 in diabetics (Pope et al., 2006, 091246; Wellenius et al.,
2006, 088748; Zanobetti and Schwartz, 2005, 088069).
      Panel and cohort studies have been conducted to determine the physiological changes that
occur in individuals with diabetes in response to PM exposure. These studies examined both changes
in inflammatory markers along with specific physiological alterations in the cardiovascular system.
Schneider et al. (2008, 191985) in a panel study of 22 individuals with type 2 diabetes mellitus in
Chapel Hill, NC found evidence that ambient exposure to PM2.5 enhanced the reduction in various
markers of endothelial function. Liu et al. (2007, 156705) observed an increase in end-diastolic FMD
and end-systolic FMD, and decreases in end-diastolic basal diameter and end-systolic basal  diameter
in diabetics upon exposure to PMi0. The authors also observed positive associations with FMD and
blood pressure in diabetic individuals. A controlled human exposure study conducted by Carlsten et
al. (2008,  156323) found that DE did not elicit any prothrombotic effects in subjects with metabolic
syndrome, which consists of physiological alterations similar to those observed in both diabetic and
obese individuals. An examination of biomarkers found mixed results, with Liao et al.  (2005,
088677) observing an increase in vWF; Liu et al. (2007, 156705) observing an increase in TEARS,
but not CRP or TNF-a; and Dubowsky et al. (2006, 088750) observing an  increase in CRP and
WBCs. Overall, it is unclear how differences in each of the aforementioned biomarkers contribute to
the potential overall cardiovascular effect observed in diabetic individuals; however, an increase in
inflammation,  oxidative stress, and acute phase response may contribute to cardiovascular effects. A
recent toxicological study (Sun et al., 2009, 190487), also demonstrated the potential for PM-related
health effects in diabetics. Sun et  al. (2009, 190487) found that PM2.5 CAPs exposure for 4 mo can
exaggerate insulin resistance, visceral adiposity, and inflammation in a diet-induced obesity  mouse
model.
      Overall, epidemiologic studies have reported evidence for increased effects in diabetics in
response to PM exposure, with preliminary evidence for pathophysiologic alterations from
toxicological studies. This potentially susceptible population is large, with an estimated 17.1 million
diabetic individuals in the U.S. (Table 8-3). However, the limited evidence from toxicological and
controlled human exposure studies along with the lack of studies that examined  additional PM size
fractions warrants additional research to confirm the associations observed and to identify the
biological pathway(s) that may result in a greater response to PM in diabetics.
      In addition to diabetes, obesity has been examined as a health condition with the potential to
lead to an increase in PM-related health effects. Only a few recent studies have examined the
potential effect modification  of PM risk estimates by obesity. Schwartz et al. (2005, 086296)
reported a change in HRV in obese (i.e., BMI > 30 kg/m2) compared to non-obese subjects, while
Dubowsky et al. (2006, 088750) observed an increase in inflammatory markers (i.e., CRP, IL-6, and
WBC) in response to short-term exposure to PM2 5 among obese individuals. Additionally, Schneider
et al. (2008, 191985) found some evidence for a larger reduction in FMD in individuals with a BMI
>30 kg/m3 in response to PM2 5 exposure. These effects could be due, in part, to  a higher PM dose
rate in obese individuals, which has been demonstrated in children by Bennett and Zeman (2004,
155686). These investigators also reported that tidal volume and resting minute ventilation increased
with body mass index. Although a limited amount of research has been conducted to examine PM-
related health effects in obese individuals there is an increasing trend of individuals within the U.S.
that have been defined as overweight (BMI > 25.0) or obese (BMI > 25.0), with the prevalence of
overweight individuals increasing from 20-74% from 1960 to 2004, and the prevalence of obese
individuals increasing  from 13.3-32.1% (NCHS, 2006, 198921).


8.1.7.  Socioeconomic Status

      SES is a composite measure that usually consists  of economic status, measured by income;
social status measured by education; and work status measured by occupation (Dutton and Levine,
1989, 192052). Based  on data from the U.S. Census Bureau in 2006, from among commonly-used
indicators of SES, about 12% of individuals and 11% of families are below the poverty line
(U.S.  Census, 2009, 192147). Although the measure of SES is composed of a multitude of
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surrogates, each of these linked factors can influence an individual's susceptibility to PM-related
health effects. Additionally, low SES individuals have been found to have a higher prevalence of
pre-existing diseases; inadequate medical treatment; and limited access to fresh foods leading to a
reduced intake of antioxidant polyunsaturated fatty acids and vitamins, which can increase this
population's susceptibility to PM (Kan et al., 2008, 156621).
      Surrogates of SES, such as educational attainment, have been shown in some studies to
modify health outcomes of PM exposure for a population.  Within the U.S. approximately 16% of the
population does not have a high school degree and only 27% have a bachelor's degree or higher
level of education (U.S. Census, 2009, 192148). Educational attainment generally coincides  with an
individual's income level, which is correlated to other surrogates of SES, such as residential
environment (Jerrett et al., 2004, 087379). Franklin et al. (2008, 155779) noted an increased risk in
mortality associated with short-term exposure to PM2.5 and its components for individuals with low
SES while additional analyses  stratified by education level have also observed consistent trends of
increased mortality for PM25 and PM2 5 species  for individuals with low educational attainment
(Ostro et al., 2006, 087991; Ostro et al., 2008, 097971; Zeka et al., 2006, 088749). This is further
supported by a reanalysis of the ACS cohort (Krewski et al., 2009, 191193). which found moderate
evidence for increased lung cancer mortality in individuals with a high school education or less
compared to individuals with more than a high  school education in response to long-term exposure
to PM2 5. However, when examining education  level and IHD mortality due to long-term exposure to
PM2 5 Krewski et al. (2009, 191193) observed an inverse relationship.
      Epidemiologic studies have also examined additional surrogates of SES, such as residential
location and nutritional status to identify their influence on the susceptibility  of a population. Jerrett
et al. (2004, 087379) examined the modification of acute mortality effects due to particulate air
pollution exposure by residential location in Hamilton, Canada using educational attainment as a
surrogate for SES. The authors found that the area of the city with the highest SES characteristics
displayed no evidence of effect modification while the area with the lowest SES characteristics had
the  largest health effects.  Likewise, Wilson et al. (2007, 157149) examined the effect of SES on the
association between mortality and short-term exposure to PM in Phoenix, but used educational
attainment and income to represent SES. When stratifying Phoenix into central, middle, and outer
rings of varying urban density central Phoenix,  the area with the lowest SES, was found to exhibit
the  greatest association with PM2 5. However, the association with urban density differed when
examining PMi0_2.5, with the greatest effect being observed for the middle ring. Yanosky et al. (2008,
192081) examined whether long-term exposure to traffic-related pollutants, using NO2 as a
surrogate, varied by SES  at the block group level. The authors found higher levels of NO2 associated
with lower SES areas, which suggests that lower SES individuals  are disproportionately exposed to
traffic-related pollutants,  which includes PM.
      Nutritional deficiencies have been associated with increased susceptibility to a variety of
infectious diseases and chronic health effects. Low SES may decrease access to fresh foods,  and thus
be related to nutritional deficiencies that could increase susceptibility to PM-related health effects.
Baccarelli et al. (2008,  157984) examined the association between exposure to PM2 5 and HRV in
individuals with polymorphisms in MTHFR and cSHMT genes, which are associated with reduced
enzyme activity and increased risk of CVD. The authors found that when individuals with these
genetic polymorphisms increased their intake (above median levels) of B6, B12, or methionine no
PM2 5 effect on HRV was observed.


8.1.8.  Summary

      Upon evaluating the association between short- and  long-term exposure to PM and various
health outcomes, studies also attempted to identify populations that are more susceptible to PM.
These studies did so by: conducting stratified analyses; examining individuals with an underlying
health condition; or developing animal models that mimic  the physiological conditions associated
with an adverse health effect. These studies identified a multitude of factors that could potentially
contribute to whether an individual is susceptible to PM (Table 8-2). Although studies have primarily
used exposures to PMi0 or PM2 5, the available evidence suggests that the identified factors may also
enhance susceptibility to  PMi0_2.5.
      The majority of observations made during the evaluation of the literature reviewed in this ISA
are  consistent with those reported in the 2004 PM AQCD.  An evaluation of age-related health effects
suggests that older adults have heightened responses for cardiovascular morbidity with PM exposure.
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In addition, epidemiologic and toxicological studies provide evidence, which indicates that children
are at an increased risk of PM-related respiratory effects. It should be noted that the health effects
observed in children could be initiated by exposures to PM that occurred during key windows of
development, such as in utero. Studies that focus on exposures during development have reported
inconsistent findings (see Section 7.4.), but a recent toxicological study suggests that inflammatory
responses in pregnant women due to exposure to PM could result in health effects in the developing
fetus.
      Epidemiologic studies have also examined whether additional factors, such  as gender, race, or
ethnicity modify the association between PM and morbidity and mortality outcomes. Consistent with
the findings of the 2004 PM AQCD, gender and race do not seem to modify the association between
PM and morbidity and mortality  outcomes. However, some evidence, albeit from two studies
conducted in California, suggest  that Hispanic ethnicity may modify the association between PM and
mortality.
      Recent epidemiologic and  toxicological studies provided evidence that individuals with null
alleles or polymorphisms in genes that mediate the antioxidant response to oxidative stress (i.e.,
GSTM1), regulate enzyme activity (i.e., MTHFR and cSHMT), or regulate  levels  of procoagulants
(i.e., fibrinogen) are more susceptible to PM exposure. However, some studies have shown that
polymorphisms in genes (e.g., HFE) can have a protective effect upon PM exposure. Additionally,
preliminary evidence suggests that  PM exposure can impart epigenetic effects (i.e., DNA
methylation), however, this requires further investigation.
      Collectively, the evidence from epidemiologic and toxicological, and to a lesser extent,
controlled human exposure studies  indicate increased susceptibility of individuals with underlying
cardiovascular diseases and respiratory illnesses, specifically asthma, to PM exposure. Additional
controlled human exposure and toxicological studies provide some evidence for increased PM-
related cardiovascular effects in individuals with underlying respiratory health conditions. However,
the results are not consistent with epidemiologic studies, resulting in the need for further
investigation.
      Recently  studies have begun to examine the influence of preexisting chronic inflammatory
conditions, such as diabetes and obesity, on PM-related health effects. These studies have found
some evidence for increased associations for cardiovascular outcomes along with physiological
alterations in markers of inflammation, oxidative stress, and acute phase response. However more
research is needed to thoroughly  examine the effect of PM  exposure on obese individuals and to
identify the biological pathway(s) that could lead to increased susceptibility of diabetic and obese
individuals to PM.
      There is also evidence that SES, measured using surrogates such as educational attainment or
residential location, modifies the association between PM and morbidity and mortality outcomes. In
addition, nutritional status, another surrogate of SES, has been shown to have protective effects
against PM exposure in individuals that have a higher intake in some vitamins and nutrients.
      Overall, the epidemiologic, controlled human exposure, and toxicological studies evaluated in
this review provide evidence for  increased susceptibility for various populations. Although the level
of evidence varies depending on  the factor being evaluated collectively, it can be concluded that
some populations are more susceptible to PM than the general population.
December 2009                                  8-16

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                  Chapter  9. Welfare  Effects
9.1.  Introduction

      This chapter is a synthesis and evaluation of the most policy-relevant science used to help
form the scientific foundation for review of the secondary (welfare-based) NAAQS aimed at
protecting against welfare effects of ambient airborne PM. Specifically, Chapter 9 assesses the
effects of atmospheric PM on the environment, including: (1) effects on visibility; (2) effects on
climate; (3) ecological effects; and (4) effects on materials. These sections initially highlight the
conclusions from the 2004 PM AQCD (U.S. EPA, 2004, 056905). followed by an evaluation of
recent publications and assessment of the expanded body of evidence.  In some sections, few new
publications are available, and the discussion is primarily a brief overview of the key conclusions
from the previous review.
      As discussed in Chapter 1, the effects of particulate NOX and SOX have recently been
evaluated in the ISA for Oxides of Nitrogen and Sulfur - Ecological Criteria  (U.S. EPA, 2008,
157074). That ISA focused on the effects from deposition of gas- and particle-phase pollutants
related to ambient NOX and SOX concentrations that can lead to acidification and nutrient
enrichment, as well as on the potential for increased  mercury methylation from SO42~ deposition.
Thus, emphasis in this document is placed on the effects of airborne PM on visibility and climate,
and on the deposition effects of PM constituents other than NOX and SOX, primarily metals and
carbonaceous compounds.
      Chapter 2 of this assessment provides an integrative overview of the major welfare effects
evaluated. EPA's framework for causality, described  in Chapter 1, is applied throughout the
evaluation and the causal determinations are highlighted.
9.2.  Effects on Visibility
9.2.1.  Introduction
      In recent years, most visibility research involved characterizing visibility conditions and trends
over broad regional scales, improving the understanding of the atmospheric processes and pollutants
responsible for the regional impacts, and attribution of visibility-impairing pollutants to emission
sources, source types, and regions. The motivation for much of this work has come from the
visibility protection provisions of the 1977 Clean Air Act Amendments (CAAA) that called for the
development of regulations to address reduction of regional haze in 156 NPs and wilderness areas to
natural conditions, and from the subsequent Regional Haze Rule (RHR) promulgated in 1999 by
EPA in response to the CAA mandate. Implementation of the RHR entails planned emissions
reductions to reach natural haze  conditions in these protected areas by 2064 in six 10-year planning
steps.
      Haze conditions caused solely by PM from natural sources are  generally much lower than
contemporary conditions. The largest difference is between natural and current conditions for the
inorganic salts ammonium sulfate and ammonium nitrate, with natural concentrations taken to be
just a few tenths of a (ig/m3 each (Trijonis et al., 1990, 157058). while current conditions  of both
over large regions of the country are an order of magnitude or more larger (DeBell, 2006, 156388).
 Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
 Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
 developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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However, natural source PM can be substantial on an episodic basis for crustal mineral PM
components during high windblown dust conditions and for carbonaceous PM from biomass
combustion during wildfire and prescribed burning episodes. The need for information to generate
RHR implementation plans has resulted in extensive use of continental-scale air quality simulation
modeling and assessment of expanded ambient monitoring data sets.
      Unlike the substantial remote-area visibility investigations that have been conducted in
response to the RHR, relatively little work on urban visibility effects has been done in recent years.
For example, there has been relatively little new research on the optical and human perceptual
aspects of atmospheric visibility over the last decade or more. These topics have been the subjects of
numerous earlier investigations that have been summarized in detail elsewhere (Latimer and Ireson,
1980, 035723: Middleton, 1952, 016324: Tombach  and McDonald, 2004, 157054: Trijonis et al,
1990, 157058: U.S. EPA, 1979,  157065: Watson et al., 2002, 035623). including past criteria
documents on PM, SO2 and NOX (U.S. EPA, 1982, 017610: U.S. EPA, 1993, 017649: U.S. EPA,
2004, 056905).
      In spite of this fact, the understanding of urban visibility conditions has continued to improve.
By applying a well established algorithm that relates PM and haze conditions to data currently
collected from routine filter-based PM chemical speciation monitors located in numerous urban areas
(Jayanty, 2003, 156605). and to  data collected from the more recently deployed high time- and
size-resolved PM speciation monitors located in several cities such as those in the PM Supersites
program (Solomon and Hopke, 2008,  156997) urban visibility conditions can be better
characterized. Comparisons between urban and remote area data in the same region afford the
opportunity to  differentiate between regional and local visibility impacts. The availability of better
size and time resolution PM composition data, compared to that available from the routine
monitoring programs,  reduces the number of simplifying assumptions required to estimate visibility
conditions in these areas, thereby reducing the uncertainty of the estimates. Thus, the state of the
science supporting urban visibility assessments continues to improve.
      The background section below contains an overview of long-available information to help
provide context to the  more recently published literature summarized in subsequent sections.


9.2.2.  Background

      Air pollution-induced visibility impairment is caused by the loss of image-forming light (i.e.,
signal) and the addition of non-image forming light (i.e., noise) between an  observer and the object
being viewed. These changes to the light reaching the observer are  a result of light being scattered
and absorbed by  particles and gases in the sight path (see the schematic in Figure 9-1).
Electromagnetic  theory developed to characterize the interaction of light with matter (Mie, 1908,
155983) permits  the calculation of light scattering and absorption by particles and gas molecules
where the index of refraction and shape of particles by size are known (Van de Hulst, 1981, 191972).
      The ability of human observers to visually detect distant objects or identify changes in their
appearance depends on the apparent contrast of the object against its background. The apparent
contrast is affected by  changes in the physicochemical characteristics of the atmosphere caused by
air pollution as well as factors not related to air quality such as length of the sight path, scenic
lighting and the physical characteristics of the viewed object and other elements of the  scene. To
rigorously determine the perceived visual  effects of changes in the  optical properties of the
atmosphere requires the use of radiative transfer modeling to determine changes in light from the
field of view experienced by the observer, followed by the use of psychophysical modeling to
determine the response to the light by the eye-brain system. The complexity of such an approach
discourages its common use.
      Atmospheric light extinction is a fundamental atmospheric optics metric used to  characterize
air pollution impacts on visibility. It is the fractional loss of intensity in a light beam per unit distance
due to scattering and absorption by the gases and particles in the air. Light extinction (6ext) can be
expressed as the  sum of light scattering by particles (&s,p), scattering by gases (bStg), absorption by
particles (bAf) and absorption by gases (b^. Light extinction and its components are expressed in
units of inverse length, typically either inverse kilometers (km"1) or, as will be the convention in this
document, inverse megameters (Mm"1). Traditionally, for visibility-protection applications, the most
sensitive portion of the spectrum for human vision (550 nm) has been used to characterize light
extinction and  its components.
December 2009                                  9-2

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             Light from clouds
             scattered into
             sight path
                                         Image-forming
                                                              light scattered   f
                                                              out of sight path
Sunlight ^-         ^
scattered Ljght ref,eet^d

        from ground
        scattered into
        sight path
                                              Image-forming
                                              light absorbed
                                                                             Source: Malm (1999, 0250371.

Figure 9-1.    Important factors involved in seeing a scenic vista are outlined. Image-forming
              information from an object is reduced (scattered and absorbed) as it passes
              through the atmosphere to the human observer. Air light is also added to the
              sight path by scattering processes. Sunlight, light from clouds, and
              ground-reflected light all  impinge on and scatter from particulates located in the
              sight path. Some of this scattered light remains in the sight path, and at times it
              can become so bright that the image essentially disappears. A final important
              factor in seeing and appreciating a scenic vista are the characteristics of the
              human observer.

      A parametric analysis has shown that a constant fractional change in light extinction results in
a similar perceptual change regardless of certain baseline conditions (Pitchford et al., 1990, 156871).
From this assessment, the deciview haze index, which is a log transformation of light extinction,
similar in many ways to the decibel index for acoustic measurements, was developed (Pitchford  and
Malm, 1994, 044922). A one deciview (Idv) change is about a 10% change in light extinction, which
is a small change that is detectable for sensitive viewing situations.  The haze index in deciview units
is an appropriate metric for expressing the extent of haze changes where the perceptibility of the
change is an issue. The RHR has adopted  the deciview haze index as the metric for tracking
long-term haze trends of visibility-protected federal lands (U.S. EPA, 2001, 157068). Light
extinction and its components are more useful metrics for characterizing the apportionment of haze
to its pollutant components due to the approximately linear relationship between pollutant species
concentrations and their contributions to light extinction.
December 2009
                        9-3

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                                                                                 starlight
                                                                                 absorbed
                               moonlight
                               scattering
                          ","*! by particles
                               starlight
                              scattered
                                                                     urban light pollution
                                                                    reflocttv* cloud
                       observer in » non-urban setting
                                                  r»ll«cliv« cloud
                                                                                      affected by
                                                                                      unnaturally
                                                                                        bright
                                                                                       nighttime
                                                                                         sky
               moonlight  f
               scattering
               by particles
                                                    S   puticl*       \,'
                                                    '     Sid.        X
                                                                                 starlight
                                                                                 absorbed
                              starlight
                              scattered
             bright urban nighttime sky
                                                                             > A        particle
                                                                             \          back
Figure 9-2.     Schematic of remote-area (top) and urban (bottom) nighttime sky visibility
                showing the effects of PM and light pollution.

       Daytime visibility has dominated the attention of those who have studied the visibility effects
of air pollution, though nighttime visibility is also known to be affected by air pollution. Stargazing
is a popular human activity in urban and remote settings. The reduction in visibility of the night sky
is primarily dependent on the addition of light into the sight path, the brightness of the night sky, and
the reduction in contrast of stars against the background (see the schematic in Figure 9-2). These are
December 2009
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controlled by the addition of PM, which enhances scattering, and the addition of anthropogenic
sources of light. Scattering of anthropogenic light contributes to the "skyglow" within and over
populated areas, adding to the total sky brightness. The visual result is a reduction of the number of
visible stars and the disappearance of diffuse or subtle phenomena such as the Milky Way. The
extinction of starlight is a secondary and minor effect also caused by increased scattering and
absorption. Anthropogenic light sources include artificial outdoor lighting, which varies dramatically
across space. Natural sources include the Moon, planets, and stars that have a predictable rhythm
across time.
      The nighttime visual environment has some important differences to note. Light sources and
ambient conditions are typically five to seven orders of magnitude dimmer at night than in sunlight.
Moonlight, like sunlight,  introduces light throughout an observer's sight path at a constant angle. On
the other hand, dim starlight emanates from all over the celestial hemisphere while artificial lights
are concentrated in cities  and illuminate the atmosphere from below. Sight paths are often inclined
upward at night as targets may be nearby terrain features or celestial phenomena. Extinction behaves
the same at night as during the day, lowering the contrast of scenes through scattering and
absorption; nevertheless the different light sources will yield variable changes in visibility as
compared to what has been established for the daytime scenario. Little research has been conducted
on nighttime visibility. Even if the air quality-visibility interactions are shown to be similar between
day and night settings, the human psychophysical response at night is expected to differ.  Though
recent advances in the ability to instrument and quantify nighttime scenes (Duriscoe et al., 2007,
156411) have been made  and can be utilized to evaluate nocturnal visibility, the state of the science
is not yet comparable to that associated with daytime visibility impairment. The remainder of this
document focuses exclusively on daytime visibility.


9.2.2.1.   Non-PM Visibility Effects

      Light extinction due to the gaseous components of the atmosphere is relatively well
understood and well estimated for any atmospheric conditions. Absorption of visible light by gases
in the atmosphere is primarily by NO2, and can be directly and accurately estimated from NO2
concentrations by multiplying by the absorption efficiency. Scattering by gases is described by the
Rayleigh scattering theory.
      NO2 absorbs more light in the short wavelength blue portion of the spectrum than at longer
wavelengths. For this reason a plume or layer of NO2 removes more of the blue light from the  scene
viewed through the layer  giving a yellow or brown appearance to the layer or plume. This filtering of
blue light by NO2 can deepen the brown appearance of hazes over urban areas, although it is not the
sole  cause of such discoloration (U.S. EPA,  1993, 017649). The photopic-weighted absorption
efficiency at the 550 nm wavelength is incorporated into the revised version of the algorithm for
estimating light extinction from aerosol data that is used for implementing the RHR (Pitchford et al.,
2007, 098066). However, NO2 is not routinely measured at any  of the monitoring sites representing
visibility protected areas where its impacts are assumed to be inconsequential compared to those of
PM.  At background concentrations NO2 absorption is generally less than five percent of the light
scattering by clean air (Rayleigh scattering), making it imperceptible. Plume visibility models  are
available to  assess both achromatic contrast and discoloration associated with NO2 light absorption,
for point source emissions (Latimer and Ireson, 1980, 035723;  Seigneur et al., 1984, 156965).


9.2.2.2.   PM Visibility  Effects

      Particle light extinction is more complex than that caused by gaseous components. PM is
responsible for most visibility impairment except under near-pristine conditions, where Rayleigh
scattering is the largest contributor to light extinction or in plumes of combustion sources that  are
well-controlled for particulate emissions (e.g., coal-fired power plants with bag houses),  where light
absorption by NO2 may dominate the light extinction.
      Light-absorbing carbon (e.g., DE soot and smoke) and some crustal minerals are the only
commonly occurring airborne particle components that absorb light. All  particles scatter light,  and
generally particle light scattering is the largest of the four light extinction components. While a
larger particle scatters more light than a similar shaped smaller particle of the same composition, the
light scattered per unit of mass concentration (i.e., mass scattering efficiency in units of
Mm'Vfug/m3] which reduces to m2/g) is greatest for particles with diameters  from -0.3-1.0 um. If
December 2009                                  9-5

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the index of refraction, particle shape and concentration as a function of particle size are well
characterized, Mie theory can be used to accurately calculate the light scattering and absorption by
those particles. However, it is rare that these particle properties are known, so assumptions are used
in place of missing information to develop a simplified calculation scheme that provides an estimate
of the particle light extinction from available data sets.
      Particles composed of water soluble inorganic salts (i.e., ammoniated sulfate, ammonium
nitrate, sodium chloride, etc.) are hygroscopic in that they absorb water as a function of relative
humidity to form a liquid solution droplet. Aside from the chemical consequences of this water
growth, the droplets become larger when relative humidity increases, resulting in increased light
scattering. Hence, the same PM  dry concentration produces more haze. Figure 9-3 shows the effect
of water growth as a function of relative humidity on light scattering for two size distributions of
ammonium nitrate and ammonium sulfate particles  as well as for internal and external mixtures (i.e.,
mixed within the same particle and in separate particles, respectively) of the two components. This
figure illustrates a number of important points. The water growth effect is substantial with an
increase in light scattering by about a factor of 10 between 40% and 97% relative humidity for the
same dry particle concentrations. The amount of scattering is significantly dependent on the dry
particle size distribution. However the growth curves for ammonium sulfate, ammonium nitrate and
mixtures of the two particle components are similar at any of the dry particle size distributions.
Water growth curves are also available for sodium chloride, the major component in sea salt, which
is an important PM component at coastal locations.
                              0.1
                         JQ
                         'o
                         o
                         O
                         O)
                         c
                         I
                         "ro
                         o
                             0.01
                            0.001
                                   	NH,NO,
                                       (NH4)2S04
                                      - External Mixture
                                        (55.5% nitrate + 44.5% sulfate)
                                       Internal mixture
                                   40   50   60    70    80   90   100

                                                 %RH
                                           Source: Reprinted with Permission of the American Geophysical Union from Tang (1996,1570421.


Figure 9-3.     Effect of relative humidity on light scattering by mixtures of ammonium nitrate
               and ammonium sulfate.

      Using Mie theory, the scattering and absorption of any wavelength of light by a particle of
known size and index of refraction (a function of the wavelength of light) can be calculated
(Van de Hulst,  1981, 191972). Particle density is used to convert the particle light extinction to  its
mass extinction efficiency (i.e., the ratio of particle light extinction to its mass). To expand the
calculations from one particle at a time to the multitude of particles in ambient aerosol, information
December 2009
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about the aerosol size and composition distributions are needed. Aerosol mixture refers to how the
major components that make up the particles are mixed. Methods have been developed to treat
simple mixture models ranging from external mixtures where the various components are assumed to
be in separate particles, to multi-component mixtures where individual particles contain several
components (Ouimette and Flagan, 1982, 025047). The latter includes internally mixed particles
where two or more components are mixed within the particles, and layered aerosol with a core of
one component covered by a shell of another component.
      The Mie theory solution for an external mixture can be simplified to a linear relationship
where the light extinction is the sum of the mass concentration of each species multiplied by its
specific mass extinction efficiency (Ouimette and Flagan, 1982, 025047). This formulation
promotes the concept of apportioning the light extinction among the various PM species. For
internally mixed aerosol, the light extinction response to adding or removing mass of any component
to the aerosol is dependent on how such changes would affect the particle size,  density and index of
refraction distribution of the aerosol. However, a number of investigators have shown that the
differences among the calculated  light extinction values using external and various internal mixture
assumptions are generally less than about 10% (Lowenthal et al., 1995, 045134; Ramsey, 1966,
013946: Sloane, 1983, 025039: Sloane, 1984, 025040: Sloane, 1986, 045954: Sloane and Wolff,
1985, 045953: Wolff, 1985, 044680). This provides a basis to accept the apportionment of light
extinction to the PM components  calculated using an external mixture assumption as a meaningful
surrogate for their contributions.
      Ambient aerosols are usually a complex and unknown combination of both internal and
external mixtures of the particle components. Despite these complexities, PM light scattering can be
accurately calculated for any relative humidity if the chemical composition as a function of dry
particle size is  known (Hand et al., 2002, 190367:  Malm and Pitchford,  1997, 002519).  However,
most routinely available ambient  monitoring programs do not include data with sufficient detail to
make such calculations. The IMPROVE network with its greater than 150 remote area monitoring
sites (DeBell, 2006, 156388) and  the CSN (Jayanty, 2003, 156605) with its greater than  150 urban
area monitoring sites collect 24-h duration fine particle samples (PM2.5) that are analyzed for the
major PM components including  SO42~, nitrate,  and carbonaceous particulate. CSN also analyzes for
ammonium ion, but does not monitor coarse mass  (PMi0_2.s), while IMPROVE measures coarse mass
but does not analyze for ammonium ion. Neither data set has sufficient size resolution to make Mie
theory calculations of light extinction, nor does  either program routinely monitor NO2
concentrations, which would be required to calculate its contribution to light extinction by
absorption.
      A simple algorithm similar  in form to the  linear equation that results from Mie theory applied
with an external mixture assumption is frequently  used to estimate light extinction from the
concentrations of the major components. The concentration of each of the major aerosol components
is multiplied by a dry extinction efficiency value and for the hygroscopic components (e.g.,
ammoniated sulfate and ammonium nitrate) an additional multiplicative term to account for the
water growth to estimate that components contribution to light extinction. Both the dry extinction
efficiency and  water growth terms are developed by some combination of empirical assessment and
theoretical calculation using typical particle size distributions associated with each of the major
aerosol components, and they are evaluated by comparing the algorithm estimates of light extinction
with coincident optical measurements.  Summing the contribution of each component gives the
estimate of total light extinction. The most commonly used of these is referred to as the IMPROVE
algorithm because it was developed specifically to use the IMPROVE aerosol monitoring data and
was evaluated using IMPROVE optical measurements at the subset of sites that make those
measurements  (Malm et al., 1994, 044920). The formula for the traditional IMPROVE algorithm is
shown below.
December 2009                                  9-7

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                               bext *  3 x /(/iff) x [Sulfate]

                                    + 3xf(RH)x[Nitrate]

                                    + 4 x [Organic Mass]

                                    + 10 x [Elemental Carbon]

                                    + 1 x [Fine Soil]

                                    + 0.6 x [Coarse Mass]

                                    + 10
                                                                                   Equation 9-1
                                                                           Source: DeBell (2006.1563881

      Light extinction (6ext) is in units of Mm"1, the mass concentrations of the components indicated
in brackets are in ug/m , andf(RH) is the unitless water growth term that depends on relative
humidity. The dry extinction efficiency for particulate organic mass is larger than those for
particulate SO42~ and nitrate principally because the density of the dry inorganic compounds is
higher than that assumed for the PM organic mass  components. Since IMPROVE does not include
ammonium ion monitoring, the assumption is made that all  SO42~ is fully neutralized ammonium
sulfate and all nitrate is assumed to be ammonium  nitrate. Though often reasonable, neither
assumption is always true (see Section 9.2.3.1). In  the eastern U.S. during the summer there is
insufficient ammonia in the atmosphere to neutralize the SO42~ fully. Fine particle nitrates  can
include sodium or calcium nitrate, which are the fine particle fraction of generally much coarser
particles due to nitric acid interactions with sea salt at near-coastal areas (sodium nitrate) or nitric
acid interactions with calcium carbonate  in crustal  aerosol (calcium nitrate). Despite the simplicity of
the algorithm, it performs reasonably well and permits the contributions to light extinction from each
of the major components (including the water associated with the SO42~ and nitrate compounds) to
be separately approximated.
      Thef(RH) terms inflate the particulate SO42~ and nitrate light scattering for high relative
humidity conditions. For relative humidity below 40% thQ/(RH) value is 1, but it increases to 2 at
-66%, 3 at -83%, 4 at -90%, 5 at -93%  and  6 at -95% relative humidity. The result is that both
particulate SO42~ and nitrate are more efficient per  unit mass than any other aerosol component for
relative humidity above -85% where its total light extinction efficiency exceeds the 10m2/g
associated with EC. Based on this algorithm, particulate SO42~ and nitrate are estimated to have
comparable light extinction efficiencies (i.e.,  the same dry extinction efficiency andf(RH)  water
growth terms), so on a per unit mass concentration basis at any specific relative humidity they are
treated as equally effective contributors to visibility effects. The strong relationship  demonstrated
between dry light scattering and fine PM mass concentration or ambient light extinction and fine PM
mass concentration under low relative humidity conditions noted by a number of investigators
(Charlson et al, 1968, 095355; Chow et al, 2002,  037784; Chow et al., 2002, 036166; McMurry,
2000, 081517; Samuels et al., 1973, 070601;  Waggoner and Weiss, 1980, 070152; Waggoner et al.,
1981, 095453) is reasonable based on this algorithm when the PM fractional composition is either
relatively constant  or varies most among PM components with similar dry extinction efficiency
values (e.g., SO42~, nitrate and organic mass efficiencies).


9.2.2.3.    Direct  Optical Measurements

      Light extinction and its components (i.e., scattering and absorption by particles and  gases) can
be determined directly by optical measurements using commercially available instruments (Trijonis
et al., 1990, 157058). Though these measurements are all wavelength dependent, the convention for
visibility monitoring purposes is to make measurement at or near 550 nm, which is the wavelength
of maximum eye response. Direct PM light extinction, scattering and absorption measurements offer
a number of advantages compared to  estimates using an algorithm applied to PM speciation data.
The direct optical measurements are considered more accurate because they do not depend on the
assumed particle characteristics (e.g., size, shape, density, component mixture, etc.) thought to be
associated with the major PM species. Also the optical measurements are made with high time
resolution (e.g., minutes to hourly) compared with the filter composition based estimates that are
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typically 24-h duration, allowing the former to better characterize sub-daily temporal patterns which
can help in identifying influential source categories and characterize atmospheric phenomenon. The
higher time resolution attainable with direct light extinction measurements are also more
commensurate than the 24-h light extinction estimates from PM samples with the short exposure
time associated with perceived visibility effects.
      Path-averaged light extinction can be determined by long-path transmissometers that monitors
the intensity of light that has traversed a known distance from a known initial intensity light source.
Transmission (i.e., the ratio of the final to the initial light intensity) is the natural logarithm of the
product of the path-averaged light extinction and the distance the light has traversed.
Transmissometer path-length establishes the useful range of light extinction over which the
measurements can be accurately measured, with path-lengths of 10 km or more required for pristine
conditions and <1 km more appropriate for hazier situations or to measure the visibility impacts
associated with fogs or precipitation events. The National Park Service (NPS) operated long-path
transmissometers at up to 25 locations from 1986 through 2004 (DeBell, 2006, 156388). but have
more recently discontinued their use at all but one remote area location due to the cost of
maintenance and the difficulties of performing calibration. Transmissometers are currently in routine
service at five urban areas.
      A number of instruments measure the light scattered by particles and gases from a source of
known intensity. These include forward scattering, back scattering, polar, and integrating
nephelometers. Of these the integrating nephelometers with its high sensitivity and sample control
options has been more widely used for air quality-related visibility and PM monitoring purposes,
while the robust design of the open air forward scattering instruments have seen extensive use by the
National Weather Service (NWS) Automated Surface Observing System (ASOS) for characterizing
visibility principally for transportation safety purposes (NOAA, 1998). The potential utility of the
ASOS visibility  network at about 900 locations for air quality monitoring has been established, but
the lack of resolution in the reported data is a serious impediment to this use of the data (Richards et
al., 1996. 190476).
      Integrating nephelometers draw air into a sample chamber, making it possible to modify the
sample either by changing its humidity or controlling the particle size range that is measured. This
feature makes it possible to use sample-controlled nephelometers to investigate the effects of
ambient PM size and water growth characteristic on light scattering (Covert et al.,  1972, 072055;
Malm and Day, 2001, 190431; Rood et al., 1987, 046397). For instance the coarse particle
contribution to light scattering can be estimated using a nephelometer that alternately samples
through a 2.5 um size selective inlet and a 10 urn size selective inlet. This separation by size may  be
useful in that it would allow correction of the underestimated light scattering of larger particles due
to nephelometer angular truncation errors (Anderson and Ogren, 1998, 156213). For routine
monitoring, integrating nephelometers are typically either used to measure the PM component of
light scattering when operated at ambient relative humidity or to measure dry PM light scattering as
a high-time resolution surrogate for PM mass concentration when operated with a heater or other
sample air drier. Integrating nephelometers operated at ambient conditions by the IMPROVE
program have replaced the long-path transmissometer as the principal  optical measurement at about
30 locations (DeBell, 2006, 156388).
      PM light absorption can also be inferred from measured  changes in the light transmitted
through a filter used to sample the PM compared to an identical clean filter (Bond et al., 1999,
156281). Such measurements can be made subsequent to sampling (Campbell et al.,  1995, 190171)
or continuously during sampling by using specifically designed sampler (Hansen et al.,  1982,
190368; Hansen et al., 1984, 002396). All of the filter-based methods require adjustments to the
optical measurements to account for filter and sampled particle light scattering effects associated
with particles concentrated on and within the matrix of the filters (Bond  et al., 1999,  156281).  Often
PM light absorption measurements  are used to infer BC concentration by assuming it is the dominant
PM contributor to light absorption with a near constant absorption efficiency (Allen et al., 1999,
048923; Babich  et al., 2000, 156239).  In fact commercially available aethalometers incorporate an
absorption efficiency value so they  can directly report BC concentrations. Like nephelometers,
commercially available aethalometers  can be obtained with either single or multiple-wavelength
measurement capabilities, where the multi-wavelength data can be used to better characterize the
PM. More recently these have been used to distinguish BC that absorbs light strongly over the full
visible light spectrum (e.g., DE) from brown carbon that absorbs appreciably more at shorter
wavelengths than at long wavelengths (e.g., WS) (Andreae and Gelencser, 2006, 156215).
December 2009                                  9-9

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      Other approaches to measure light absorption include a photoacoustic instrument that
measures the heating associated with absorbed light by suspended PM (Arnott et al., 1999, 020650;
Moosmuller et al., 1998, 020657), as well as by the difference between light extinction and light
scattering measurements (Bond et al., 1999, 156281).


9.2.2.4.  Value of Good Visual Air Quality

      The term visual air quality (VAQ) is used here to refer to the visibility effects caused solely by
air quality conditions. For example, it excludes the reduced visibility caused by fog. Two broadly
different approaches have traditionally been used to define and quantify the value of good VAQ. One
approach assesses the monetary value associated with visibility changes; the other assesses the
psychological value of visual air quality. With respect to the latter, reduced VAQ  is considered an
environmental stressor (Campbell, 1983, 190172) that is associated with heightened amounts of
anxiety, tension, anger, fatigue, depression, and feelings of helplessness (Evans et al., 1987, 190347;
Zeidner and Shechter, 1988, 189973). Though the relationship between impaired VAQ and mental
health is poorly understood, there are greater emergency calls associated with psychiatric
disturbances during periods with reduced VAQ (Rotton and Frey, 1982, 190477). Studies have
shown that  reduced VAQ affects people's behavior, including reductions in outdoor activities, and
increased hostility and aggressive behavior (Cunningham, 1979, 191974; Evans et al., 1982, 190521;
Jones and Bogat, 1978,  190396; Rotton et al., 1979, 190478).
      The value of VAQ (both monetary and non-monetary) has been investigated in two broadly
different settings, non-recreational or urban settings and recreational settings,  such as the NPs and
wilderness  areas where visibility is protected by the RHR (Trijonis et al., 1990, 157058). In urban
settings, public surveys have shown that greater than 80% of the participants are  aware of poor VAQ
conditions (Cohen et al., 1986,  190182). though attitudes towards poor VAQ have been shown to
vary by socio-economic  status, health, and length  of residence in the urban setting (Barker, 1976,
072137). The economic importance of urban visibility has been examined by a number of studies
designed to quantify the  benefits (or willingness to pay) associated with potential improvements in
urban visibility. Urban visibility valuation research prior to 1997 was summarized in Chestnut and
Dennis (1997, 014525). and was also described in the 2004 PM AQCD (U.S. EPA, 2004, 056905)
and the 2005 PM Staff Paper (U.S. EPA, 2005, 090209). These reviews  summarize 34 estimates
(based on different cities or model specifications)  from six different studies. Since the mid 1990s,
however, only one new valuation study of urban visibility has been published (Beron et al., 2001,
156270) which is summarized below (Section 9.2.4.6).
      In recreational settings, experience based demand models have been developed using on-site
and mail-in surveys to judge the relative importance to NP visitors of various park attributes
including good VAQ, to assess  visitor awareness of VAQ conditions, and to explore possible
relationships between VAQ  and visitor satisfaction (Ross et al., 1985, 044287; Ross et al., 1987,
037420). At the three western and two eastern NPs where this survey was  conducted, visitors rated
the attribute identified as "clean, clear air" among the most important features of the parks. A
random sample of 1,800  visitors at one of the parks (Grand Canyon) showed that visitor awareness
of VAQ impacts increased as measured visibility conditions decreased, and that overall park
enjoyment  and satisfaction decreased with reduced VAQ. Grand Canyon visitors  when asked to
indicate how they would budget their time (e.g., between visiting an  archaeological site or a view
lookout point) indicated that they would to be willing to significantly alter their behavior to
experience  views under improved VAQ (Malm et  al.,  1984, 044292).


9.2.3.  Monitoring and Assessment

      Monitoring and the assessment of monitoring data serve a number of goals with regard to the
visibility effects of PM, including improving the understanding of the physio/chemical/optical
properties of the aerosol, characterizing spatial and temporal air quality  patterns,  and assessing the
causes (i.e., pollution sources and atmospheric processes) that are responsible for visibility
impairment. Information generated by special studies employing sophisticated instrumentation are
typically needed to advance the understanding of aerosol properties, while characterizing trends is
the product of analyzing routine monitoring data. Whereas, assessing the causes of haze usually
involves a weight-of-evidence approach applied to special study and/or routine monitoring data sets
December 2009                                 9-10

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plus the use of air quality simulation modeling. This section summarizes recently available
information that is based on monitoring data.


9.2.3.1.   Aerosol Properties

      Particle size is the most influential physical property of aerosols with respect to their dry light
extinction efficiency. Chemical composition by size is used to ascertain density (needed to convert
aerodynamic  to physical size and to determine particle mass as a function of size) and to identify the
water growth characteristics of the aerosol (needed to calculate the particle size, density and index of
refraction at ambient RH). To characterize aerosol properties of interest for visibility effects, field
monitoring programs typically include particle size distribution monitoring, high size resolution
particle sampling with subsequent compositional analysis, and optical monitoring. These generate
data that permit optical closure assessments where the light scattering and/or light extinction
estimates from the aerosol data are compared to corresponding optical data. Since component
contributions to visibility are generally assessed by applying the IMPROVE or some similar
algorithm to measured or modeled aerosol concentration data, this section will include recent
investigations that evaluate or address various assumptions inherent in the use of these simple
algorithms.
      One component of the Big Bend Regional Aerosol and Visibility Observational (BRAVO)
Study, conducted at Big Bend NP, TX in the summer and fall of 1999, entailed use of detailed
measurements of aerosol chemical composition, size distribution, water growth, and optical
properties to characterize the aerosol and assess the relationship between aerosol physical, chemical
and optical properties (Malm et al, 2003, 190434; Schichtel et al, 2004, 179902). Fine ammoniated
sulfate during the BRAVO Study was about half the fine particle mass concentration and was shown
to be responsible for about 35% of the light extinction. Rayleigh scattering was the second largest
contributor at about 25%, followed by coarse particle (about 18%), and organic compounds (about
13%). There was little fine particle nitrate (less than 5% of the mass concentration) and most of it is
apparently in the form of sodium nitrate and two thirds of it was found in the coarse mode where it
comprises about 8% of the coarse particle mass concentration. Both the composition of the nitrate
and the fact of much of it being in the coarse size mode (2.5 um >D>10 um) are inconsistent with
the implied assumptions of the IMPROVE algorithm.
      A year-long special study of coarse particle speciation was conducted at nine IMPROVE
remote area monitoring sites during 2003-2004 to provide additional information about the
geographic and seasonal variations in coarse particle composition (Malm et al., 2007, 156730). The
same sampling and analytical methodologies procedures were used for the PMi0 samples as are
routinely used on the IMPROVE PM2.5 samples. The IMPROVE coarse particle speciation study did
not include ammonium analysis, so SO42~ and nitrate ions were assumed to be ammonium sulfate
and ammonium nitrate. As expected crustal minerals were the largest  contributors to coarse mass
overall (about 60%), though at Mt. Rainier the fraction of coarse PM that was organic exceeded the
crustal mineral by nearly two to one (i.e., 59.2% compared to 33.5%) On average across sites the
organic particulate contributed significantly at about one quarter of the coarse mass, while
ammonium nitrate was the third largest contributor to coarse mass (about 8%). Sea salt was
negligible overall but high at the one coastal site (i.e., 12% at Brigantine, NJ). The two California
sites, San  Gorgonio and Sequoia, had the highest coarse nitrate concentrations, 0.74 ug/m3 and
0.69 ug/m3, and high fine nitrates concentrations on average, 2.66  ug/m3 and 2.14 ug/m3,
respectively. Brigantine, a coastal site in New Jersey, had the highest fraction of total nitrate in the
coarse size range (36%). The authors  speculate that Brigantine's particulate nitrate is likely sodium
nitrate, the result of nitric acid reactions with sodium chloride. The nine-site average fraction of total
nitrate in the coarse size range is 26%. By contrast, coarse SO42~ concentrations  are small with only
about -1% of the total SO42~ in the coarse fraction.
      Routine IMPROVE monitoring data include the mass concentration, but not the composition
of the coarse  PM fraction, so the algorithm used to estimate light extinction does not include any
provision  for varied coarse PM composition as shown in this study. This study shows that about 10%
of the coarse  mass across the nine monitoring sites is composed of hygroscopic materials (i.e.,
ammonium sulfate, ammonium nitrate and sea salt), which during high humidity conditions will
scatter more light than estimated by the current algorithm (e.g., -20% bias at -90% relative
humidity). However, at coastal sites such as the Brigantine, NJ, IMPROVE site where the combined
concentration of the inorganic salts (i.e., sea salt, nitrate and SO42~) constitute a significant fraction
December 2009                                  9-11

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(-24% on average) of the coarse mass concentration, the IMPROVE algorithm underestimation of
light extinction by coarse PM can be significant for high relative humidity conditions (-60% at
-90% relative humidity). The resulting underestimation of total light extinction can be much smaller
since fine particle light extinction generally exceeds that contributed by coarse particles. Another
issue with regard to estimating light extinction from coarse PM concentration when the composition
is not crustal minerals, as has been assumed, has to do with the lower average density of the coarse
mode particles that results in greater particle numbers and/or larger particles and therefore a greater
light extinction efficiency (Malm and Hand, 2007, 155962).
      Special studies with more complete, higher time resolution and size resolved particulate
inorganic ion species chemistry and precursor gases were conducted at seven of the nine sites with
IMPROVE coarse particle speciation monitoring (Lee et al., 2008, 156686). This work confirmed
the presence of sodium and calcium nitrate (referred to as mineral nitrate) primarily in the coarse
particle size range in addition to fine particle ammonium nitrate where low temperatures, high
humidity and excess ammonium (beyond that required to neutralize  the particulate SO42~) favored
particle phase equilibrium. Figure 9-4 is a map snowing the locations and sample times and
estimated composition of the total particulate nitrate for the seven locations for this special study.
Sites with a high fraction of ammonium nitrate (e.g., San Gorgonio,  Bondville, and Brigantine) have
the highest nitrate contributions to total mass concentration and haze, whereas sites with high
mineral nitrates tend to have low total nitrate contributions. This work shows that the common
assumption that particulate nitrate is in the fine particle size range and consists principally of
ammonium nitrate is not necessarily true.
  Yossnte(July/Au
                                                                          Brigantine (November, 2003)
                                                                                       0 NaNCh
                                                                                       0 Ca(NOs)2
             San Gorgonio (July, 2003)
                                            Source: Reprinted with Permission of Atmospheric Environment from Lee et al. (2008,156686)

Figure 9-4.     Estimated fractions of total particulate nitrate during each field campaign
               comprised of ammonium nitrate, reacted sea salt nitrate (shown as NaNOs), and
               reacted soil dust nitrate (shown as Ca(NOs)2).

      Extinction efficiencies for individual particle species can be theoretically calculated from
sized-resolved aerosol measurements and can be inferred using multiple linear regression applied to
aerosol composition and light extinction measurement data. In a recent publication, Hand and Malm
(2007, 155825) reviewed the literature since 1990 in which aerosol mass scattering efficiency values
were calculated or inferred. From these they have compiled normalized dry scattering efficiency
December 2009
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values for the individual species. Based on 93 separate determinations including marine, remote
continental and urban areas data sets, the average dry mass scattering efficiency for ammonium
sulfate is 2.5 ± 0.6 m2/g. Average values tended to be somewhat lower for the marine aerosol
(~2 m2/g) than for remote continental (-2.1 m2/g) and urban (2.6 m2/g) areas, and values also tended
to be lower for fairly clean arid locations compared with more humid polluted areas.
      Based on 48 separate determinations including remote area and urban area data sets, the
average dry mass scattering efficiency for ammonium nitrate is 2.7 ± 0.5 m2/g (Hand and Malm,
2007, 155825). Average values were higher in remote locations (2.8 ± 0.5 m /g) compared to urban
locations (2.2 ± 0.5 m /g) though this might be accounted for by the predominate use of multiple
linear regression for the remote areas, which can be biased high, compared to the use of theoretical
calculations for the urban data sets.
      Organic fine PM  extinction efficiency of 3.9 ±1.5 m2/g is based on 58 separate
determinations, though  much higher values (~6 m2/g) resulted for locations influenced by industrial
and biomass combustion sources (Hand and Malm, 2007, 155825). These organic fine PM
extinction efficiency values were adjusted to use a consistent ratio of organic mass to OC (OC) of
1.8 for each determination of the mass concentration. This value is generally associated with aged
organic  PM, while for more freshly emitted PM, such as in an urban environment, a smaller ratio
(e.g.,  1.4) would be more appropriate. This could explain the discrepancy between two approaches
used to estimate the organic PM light extinction efficiency for Phoenix (Hand and Malm, 2006,
156517). which resulted in a significantly lower value where a site specific regression method was
used compared to the value obtained from a method optimized for remote-area monitoring (2.47
m2/g compared to 3.71 m2/g). However in Fresno both the mass balance and light scattering balance
was improved by using a ratio of 1.8 instead of 1.4 to estimate the organic compound mass (Watson
and Chow, 2007,  157127). Another possible or partial factor with respect to urban light extinction
efficiency for organic PM may be that the size distribution of freshly emitted organic PM in urban
areas  extends significantly into the ultra-fine particle  size range (Demerjian  and Mohnen, 2008,
156392) that is less efficient per mass concentration at light scattering than the generally larger-sized
aged organic PM such as from a distant forest fire as  was measured at the Baltimore Supersite.
      Hand and Malm (2007, 155825) also reviewed and made recommendations for extinction
efficiencies for the other PM components including mixed coarse mode (1.0 ± 0.9 m2/g based on 51
determinations) and fine mode dust or soil (3.3 ± 0.6  m2/g based on 23  determinations, but
recommending 1.0 m2/g for use with data from realistic collection efficiency samplers) and fine sea
salt (4.5 ±0.9 m2/g based on 25 determinations, but recommending 1.0 m2/g to 1.3 m2/g for use with
data from realistic collection efficiency samplers). This work did not address light absorption
efficiency of EC, CB, or crustal PM.
      The Hand  and Malm (2007,  155825) average dry mass light scattering efficiency values are
generally consistent with the values for the IMPROVE algorithm (as shown in Equation 9-1).
However the adoption of the IMPROVE algorithm by EPA for calculating the haze metric used to
track trends and assess the nominal pace of progress for the RHR (U.S. EPA, 2001, 157068) resulted
in much greater scrutiny of its performance in estimating extinction (Lowenthal and Kumar, 2003,
156712: Malm, 1999, 025037: Malm and Hand, 2007,  155962: Ryan et al, 2005, 156934). Among
the issues raised  is that the algorithm tended to underestimate the light extinction for the haziest
conditions and overestimate light extinction for the clearest conditions in regions such as the
southeastern U.S., though it generally worked well in the arid western U.S.  Furthermore, they
showed the lack  of mass or light scattering closure at coastal sites due to sea salt that was not
accounted for by the IMPROVE algorithm. These assessments used mass concentration and light
extinction closure and regression analysis methods to infer that the dry extinction efficiency for the
major fine particle components would need to vary in order to avoid the biased estimates of light
extinction at the  extremes. Theoretical calculations of SO42~ dry extinction efficiencies for 41 days of
size-resolved chemical composition data for Big Bend, TX as part of the BRAVO Study produced a
range of results from ~2.4 m2/g to ~4.1 m2/g, with the larger dry extinction efficiency values tending
to be associated with higher ammonium sulfate mass  concentration and narrower size distributions
(Schichtel et al.,  2004, 179902).
      In response to the technical concerns raised about the performance of the IMPROVE
algorithm, a revised algorithm was developed (Pitchford et al., 2007, 098066). The revised version
of the algorithm  differs  from the original algorithm by: including a fine sea salt term related to the
measured chloride ion concentration; increasing by about 30% the mass concentration of the organic
aerosol  component by changing the ratio of organic compound mass to OC mass from 1.4 to 1.8;
December 2009                                 9-13

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using site elevation dependent Rayleigh scattering in place of 10 Mm"1 that had been used at every
site; adding a NO2 light absorption term; and employing a split component model for the secondary
particulate components (i.e., SO42~, nitrate and organic species) with new water growth terms to
better estimate their extinction at the high and low extremes of the range. The revised algorithm is
displayed below in Equation 9-2.

          bext  *  2.2 x fa(Rti) x [Small Sulfati + 4.8 x  fL(RH)  x  [LargeSuJfatd

               + 2.4 x fs(Rti) x [SmallNitrat^  + 5.1  x fL(Rti) x [Large Nitrati

               + 2.8 x [Small Organic Mas&  + 6.1 x [Large Organic Mas^

               + 10 x  [ElementalCarbori

               + 1  x [FineSoiA

               + 1.7 x4(/Z#) x [SeaSaM

               + 0.6 x [Coarse Massi

               + RayleighScattering (Site Specific)

               + 0.33 x [NO2 (ppb)}
                                                                                   Equation 9-2
                             Source: Reprinted with Permission of the Air & Wast Management Association from Pitchford et al.  (2007.0980661

      Small and large SO42~, nitrate and organic mass are used to refer to the splitting of the
concentrations of each of those three species into two size distributions. This approach  accounts for
increased light extinction efficiency with mass by using a simple mixing model that assume that each
of these three components are comprised of  an external mixture of small and large particle size
modes. Conceptually, the large mode particles represent aged or cloud-processed aerosol, while the
small mode particles represent relatively newly generated particles from the gas phase precursors.
The former are more likely to be associated with high concentrations while the latter are likely to be
at relatively low concentration.
      The geometric mean diameter and standard deviations assumed for these two size modes are
0.5  um and 1.5 for the large mode particles and 0.2 urn and 2.2 for the small mode particles.  Mie
theory applied to these size distributions for  the three species results in dry extinction efficiencies for
the  small and large mode ammonium sulfate (2.2 m2/g and 4.8 m2/g), ammonium nitrate (2.4 m2/g
and 5.1 m2/g) and organic mass (2.8 m2/g and 6.1 m2/g). Water growth terms specifically derived for
the  small and large size distribution using the upper branch of the hygroscopic growth curves for
ammonium sulfate are applied to both the SO42~ and nitrate PM. No water growth is assumed for
organic PM.
      A simple empirically developed apportionment approach that was evaluated by testing the new
algorithms estimated light scattering at the 21 IMPROVE sites that have nephelometer-measured
light scattering data. For each sample, the fraction of the fine particle component (SO42~, nitrate, or
organic mass) that is assigned to the large mode is calculated by dividing the total concentration of
the  component by 20 ug/m3 (e.g., if the total fine particle nitrate concentration is 4 ug/m3, the large
mode concentration is 1/5 of 4 ug/m3 or 0.8  ug/m , leaving 3.2 ug/m3 in the small mode). If the total
concentration of a component exceeds 20 ug/m3, all of it is assumed to be in the large mode.
      Figure 9-5 and Figure 9-6 are scatterplots of the estimated versus measured light scattering for
the  two algorithms. The revised algorithm has noticeably reduced bias  at the upper and lower
extremes. However, the new algorithm estimates have somewhat reduced precision (i.e., the  points
are  more broadly scattered). States have adopted the new algorithm for the technical  assessments that
support their RHR State Implementation Plans, but the revised algorithm was too recently developed
to be incorporated into any of the peer-reviewed technical literature reported on below.  In general the
differences resulting from use of the original versus the revised IMPROVE algorithm in identifying
best and worst haze conditions  and the apportionment of the various PM components are small with
exception of coastal locations where sea salt may be a significant contributor.
December 2009                                  9-14

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                 350 -i
                 300
                             50
                                       100
                                                 150        200

                                                 Measured Bsp
                                                                     250
                                                                               300
                                                                                         350
                                    Source: Reprinted with Permission of the Air & Waste Management Associaiton from Pitchford, et al. (2007,
Figure 9-5.     A scatter plot of the original IMPROVE algorithm estimated particle light
                scattering versus measured particle light scattering.
                                       100
                                                                     250
                                                                               300
                                                                                         350
                                                 150        200

                                                 Measured Bsp

                                    Source: Reprinted with Permission of the Air & Waste Management Associaiton from Pitchford, et al. (2007,
Figure 9-6.     Scatter plot of the revised algorithm estimates of light scattering versus
                measured light scattering.
December 2009
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9.2.3.2.   Spatial Patterns

      The IMPROVE network is the basis for much of what is known about particulate species
spatial and temporal patterns for remote areas of the U.S. Though IMPROVE includes some urban
monitoring sites, most of what is known about urban particle speciation trends is based on the EPA
Speciation Trend Network (STN) and other similarly operated state particle speciation sites jointly
referred to as the Chemical Speciation Network (CSN) (Jayanty, 2003, 156605). The number of
IMPROVE network sites has increased considerably beginning in 2000, first to increase its ability to
generate data representative of the 156 visibility-protected NPs and wilderness areas, then later as
the states in the central U.S. requested additional remote-area monitoring to better understand their
contributions to regional haze. The expansion of the network into the central U.S. significantly
improved the understanding of spatial trends in a region of the country that had little speciation
monitoring. Except as otherwise noted most of the information in this section was from the
IMPROVE Report IV (DeBell, 2006, 156388) and displays of data that are readily generated using
the Visibility Information Exchange Web Site (VIEWS). VIEWS, the ambient monitoring data
system, is one of several websites (as described in Table 9-1) sponsored by the Regional Planning
Organizations (RPO) that documents substantial, though often otherwise unpublished, technical
information generated to support implementation of the RHR.
      Figure 9-7 shows maps of remote area light extinction estimates from PM speciation data for
two years  selected to demonstrate the additional information available due to the expansion of the
IMPROVE network into the central U.S. The locations of monitoring sites supplying the data shown
as color contours are shown as dot on the maps.  Users of such contour maps are usually cautioned
that the contours are only there to guide the eye to sites with similar measurements and that nothing
should be  implied about spatial patterns where there are no monitoring sites. Certainly these plots
give proof to the wisdom of such warnings. Prior to  2001 there were no IMPROVE or any other
remote-area aerosol speciation monitoring sites in the central states between northern Minnesota and
Michigan to the north and Arkansas and Kentucky to the south. The lack of monitoring over such a
large region in the center of the country hid the presence of high average regional haze over the
midwestern U.S. Smaller scale differences are seen in the rest of the country and some of those are
due to interannual variations  as well as to better spatial resolution made possible by a more dense
monitoring network.
December 2009                                 9-16

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Table 9-1.     Regional  Planning Organization websites with visibility characterization and source
                attribution assessment information.
Type of
Information
RPO Home Pages
Visibility -Air Quality
Monitoring Data
Emission Inventory
Data
Monitoring Data
Assessment
Visibility Modeling
Name and Web Address
Western Regional Air Partnership
http://www.wrapair.org/
Central Regional Air Planning Association
http://www.cenrap.org/
Midwest Regional Planning Organization
http://64.27.125.175/mrpo.html
Visibility Improvement State and Tribal
Association of the Southeast
http://www.vistas-sesarm.org/
Mid-Atlantic/Northeast Visibility Union
http://www.manevu.org/
http://www.nescaum.org/topics/regional-haze
http://www.marama.org/visibilitv/
Visibility Information Exchange Web Site
http://vista.cira.colostate.edu/views/
Emissions Data Management System
http://www.wrapedms.org/default login. asp
Causes of Haze Assessment
http://www.coha.dri.edu/
U. of California-Riverside Modeling Center
http://pah.cert.ucr.edu/agm/308/
http://pah.cert.ucr.edu/agm/cenrap/index.shtml
http://pah.cert.ucr.edu/vistas/
RPO
WRAP
CENRAP
MRPO
VISTAS
MANE-VU
NESCAUM
MARAMA
All RPOs
WRAP
WRAP
CENRAP
WRAP
CENRAP
VISTAS
Information Content and Comments


Organizational structure, plans, projects, reports and links to other sites with
additional information.
Air Use Management (NESCAU M) and Mid-Atlantic Regional Air
Management Association (MARAMA) to develop the technical information for
RHR in the Northeast. All three web sites contain unique technical support
information.

All IMPROVE and most other PM speciation data, RHR compatible derived
parameters, and user-friendly tools to summarize and display data.
WRAP emission inventory data warehouse and tools that provides a
consistent approach to regional emissions tracking
Monitoring site-specific descriptive characterizations and maps, seasonal and
trends analysis, air flow analysis, & receptor modeling.
Descriptions of input data, performance, and results of regional scale
modeling (CMAQ & CAMx) & source attribution for base and future year
regional haze.
Integrated Information  Technical Support System
to Support RHR SIP
Preparations         http://vista.cira.colostate.edu/tss/
WRAP
Provides access and common formats to display and summarize emissions
inventory information, monitoring data/ assessment and regional haze
modeling result to aid state and tribal analyst prepare RHR implementation
plans.
December 2009
      9-17

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Figure 9-7.
                                                                                           1/Mtr
                                                                  Source: VIEWS (http://vista.cira.colostate.edu/view5/)
IMPROVE network PM species estimated light extinction for 2000 (left) and for
2004 (right).
                                                                  Source: VIEWS (http://vista.cira.colostate.edu/views/)
Figure 9-8.
Mean estimated light extinction from PM speciation measurements for the first
(top left), second (top right), third (bottom left), and fourth (bottom right) calendar
quarters of 2004.
      Figure 9-8 shows the seasonal pattern of PM species estimated light extinction using maps of
mean values for each of the calendar quarter for 2004. The first quarter has the highest region of
haze centered in the midwestern U.S.; the warmer second and third quarters have the region of
highest haze over the Ohio River Valley; and the fourth quarter is a composite with high haze in both
December 2009
                               9-18

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the Midwest and Ohio River Valley. Smaller regions of haze show up in the Columbia River Valley
(border between Washington and Oregon) in the colder first and fourth quarters and in Southern
California in the warmer second and third quarters.
      The IMPROVE algorithm permits each PM component contribution to light extinction to be
separately estimated. Figure 9-9, Figure 9-10, and Figure 9-11 display the seasonal variation of the
percent contribution to aerosol light extinction by the various component estimates. Figure 9-9
shows the contributions by SO42~ and nitrate particulate including the haze enhancement caused by
the absorbed water in humid conditions. As shown in Figure 9-9, a large regional pattern of high
contribution to haze by nitrate PM is centered in the Midwest, and during the cooler months the
nitrate PM is the dominant cause of haze in the region responsible for a third to a half of the
particulate light extinction. Midwestern particulate nitrate is responsible for the regional pattern of
the highest haze conditions shifting  from the Ohio River Valley during  summer to the Midwest in the
winter as shown in Figure 9-8. Particulate nitrate is also a significant contributor to particulate light
extinction year-around in parts of California, where it generally contributes 20%-40%. The Pacific
Northwest, parts of Idaho and Utah  experience large contributions to particulate light extinction by
nitrates during the colder seasons, with contributions of 20%-30%. Figure 9-9 also  shows that
particulate SO42~ is the predominate contributor in the eastern U.S., where it contributes 40% or
more on average and during the summer months up to three quarters of the particulate light
extinction over much of the East. In the western U.S. particulate SO42~  generally contribute 20-50%
of the particle  light extinction. Regions of the lowest fractional contributions by particulate  SO42~
and nitrate for any calendar quarter are generally in the western U.S.
      Figure 9-10 shows the contributions  to haze by the carbonaceous PM components (i.e., organic
mass and EC). They show broadly similar patterns with the greatest contributions in the western U.S.
especially during  the warmer months of the year. For the most part this spatial pattern results from
the dominant contributions to haze by SO42~ and nitrate PM in the eastern half of the U.S., leaving
relatively little for other component contributions. The fractional contribution to haze by organic PM
is generally two to five times that of EC. In absolute terms, both carbonaceous components  tend to
have two to three times higher concentrations in the eastern U.S. than in the non-coastal western
states.
December 2009                                  9-19

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                                                                Source: VIEWS (http://vista.cira.colostate.edu/view5/)
Figure 9-9.
Percent contributions of ammonium nitrate (left column) and ammonium sulfate
(right column) to particulate light extinction for each calendar quarter of 2004
(first through fourth quarter arranged from top to bottom).  Note that the contour
intervals are not the same for the two species contributions.
December 2009
                              9-20

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                                                                 Source: VIEWS (http://vista.cira.colostate.edu/view5/)
Figure 9-10.
Percent contributions of organic mass (left column) and EC (right column) to
particulate light extinction for each calendar quarter of 2004 (first through fourth
quarter arranged from top to bottom). Note that the contour intervals are not the
same for the two species contributions.
December 2009
                               9-21

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                                                                 Source: VIEWS (http://vista.cira.colostate.edu/view5/)
Figure 9-11.
Percent contributions of coarse mass (left column) and fine soil (right column) to
particulate light extinction for each calendar quarter of 2004 (first through fourth
quarter arranged from top to bottom). Note that the contour intervals are not the
same for the two species contributions.
December 2009
                               9-22

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      Figure 9-11 shows the contributions to haze by coarse mass and fine soil components. As with
the carbonaceous components, these crustal dominated components have a similar spatial pattern
with regions of highest contribution to haze in the western U.S., and just as for the carbonaceous
PM,  the explanation for low contributions in the eastern U.S. is the dominant contributions to haze
by SO42~ and nitrate PM leaving relatively little for other components. The crustal components
contribute more to haze in the arid regions of the west including the southwestern deserts. In
absolute terms, coarse mass concentrations are as high in the rural areas of the center of the country
(including Oklahoma, Arkansas, Kansas, Missouri, and Iowa) as they are in the Desert Southwest.
Typically coarse mass contributions to haze exceed those of fine mass by a factor of 2-4.


9.2.3.3.   Urban and Regional Patterns

      Using a combination of IMPROVE and CSN data, it is possible to compare urban PM2.5
concentrations and composition to corresponding remote-area regional values. These are shown as
paired color contours maps for IMPROVE and IMPROVE plus CSN  (see Figure 9-12 through
Figure 9-23). The degree of comparability of the data from these 2 networks was assessed by an
analysis of two years of co-located IMPROVE and CSN data from 6 urban areas.  The CSN organic
mass data were adjusted for a positive sampling  artifact prior to inclusion in this assessment, in a
fashion  similar to that used for the IMPROVE data set (pages 29-30, DeBell,  2006, 156388). Note
that the  contour scales are different between the  two maps  for each component pair of maps so that
each contains as much information as possible using ten concentration contours. To assess the degree
to which urban areas have higher PM component concentrations compared to regional background
note  how many contour intervals surround the urban monitoring sites. The U.S. EPA (2004, 190219)
used the pairing of IMPROVE and CSN monitoring sites at 13 selected urban areas to separate local
and regional contributions of three major  PM2.5 components as shown in Figure 9-24.
      In Figure 9-12 and Figure 9-13, urban PM2.5 concentrations are systematically higher than
those in the surrounding non-urban regions. The urban excess is generally much higher in the
western U.S. than in the East (e.g., there are five contour intervals separating  Salt Lake City from its
remote regional area compared  to only two for Indianapolis). This implies that eastern and western
urban PM2.5 concentrations and resulting visibility are less different than the eastern and western
regional concentrations and visibility.
December 2009                                 9-23

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                                                    IMPROVE Site
                                                    IMPROVE Urban Site
                                                                        -l->
                                                                        *^
                                                                                  146
                                                                                  10.9
                                                                                  9.68
                                                                                  8.47
                                                                                  7.26
                                                                                  6.05
                                                                                  4.84
                                                                                  3.63
                                                                                  2.42
                                                                                  1.21
                                                                                  0.00
                                                                               Mg/m3
                                  ,
            ®  Alaska
                               Puerto Rico /
                               Virgin Islands
                                                                             Source: Debell (2006,156388).
Figure 9-12.   IMPROVE Mean PM2.s mass concentration determined by summing the major
              components for the 2000-2004.
              Alaska
                          Hawaii
                                                    (2vW1'>'~ *''*'*'-  '\
                                              \ ;v-^«x^.         *r^\

                                        \J
                                                  ASTNSite
                                        ^—M    • IMPROVE Site
                                                  • IMPROVE Urban Site
                        ,
                           •^
                                  — 307
                                   B 14.7
                                     130
                                     11 4
                                     9.78
                                     8.15
                                     6.52
                                     4.89
                                     13.26
                                     1.63
                                     0.00
                                  (jg/m3
                                       e
                               Puerto Rico /
                               Virgin Islands
                                                                             Source: Debell (2006,156388).
Figure 9-13.   IMPROVE and CSN (STN) mean PM2.s mass concentration determined by
              summing the major components for 2000-2004.
December 2009
9-24

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               Alaska
                                                  • IMPROVE Site
                                                  • IMPROVE Urban Site
Hawaii
        e
Puerto Rico /
Virgin Islands
                                                                            Source: Debell (2006,156388).
Figure 9-14.   IMPROVE mean ammonium nitrate concentrations for 2000-2004.
               Alaska
                          Hawaii
                                                  A STN Site
                                                  • IMPROVE Site
                                                  • IMPROVE Urban Site
                                                       e e
                                                  Puerto Rico /
                                                 Virgin Islands
                                                                            Source: Debell (2006,1563881.


Figure 9-15.   IMPROVE and CSN (STN) mean ammonium nitrate concentrations for 2000-2004.
December 2009
                   9-25

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                          Hawaii
                                                    IMPROVE Site
                                                    IMPROVE Urban Site
                               Puerto Rico /
                               Virgin Islands
                                                                            Source: Debell (2006,156388).
Figure 9-16.   IMPROVE mean ammonium sulfate concentrations for 2000-2004.
            *  Alaska
                          Hawaii
                                                  A STN Site
                                                  • IMPROVE Site
                                                  • IMPROVE Urban Site
                                      e
                               Puerto Rico /
                               Virgin Islands
                                                                            Source: Debell (2006,1563881.

Figure 9-17.   IMPROVE and CSN (STN) mean ammonium sulfate concentrations for 2000-2004.

      Figure 9-14, Figure 9-15, and Figure 9-24 show the PM2.5 nitrate in remote and urban areas.
Here the western states have urban particulate nitrate concentrations that far exceed twice the remote
December 2009
9-26

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area regional concentrations. For the Central Valley of California and Los Angeles areas, the urban
excess of ammonium nitrate exceeds regional concentrations by 2 ug/m3 to 12 ug/m3. In the region
of the Midwest nitrate bulge, the urban concentrations were less than twice the regional
concentrations for an annual urban excess of about 1  ug/m3. Northeast and southeast of the Midwest
nitrate bulge, annual urban particulate nitrate concentrations are several tenths to about 1 ug/m3
above the remote area regional concentrations, with warmer southern locations tending to have the
smaller concentrations of both regional and urban excess particulate nitrate.
      As shown in Figure 9-16, Figure 9-17, and Figure 9-24, annual-averaged urban particulate
SO42~ concentrations are generally not much higher than the regional values, with urban excess
generally of less than about 0.5 ug/m3. The exceptions apparent by comparing Figure 9-16 and
Figure 9-17 are in Texas and Louisiana where urban excess particulate SO42~ are >1  ug/m3, perhaps
caused by local emissions (e.g., from oil refineries). Urban contributions are a larger fraction of the
total particulate SO42~ concentrations in the western U.S. because the regional concentrations are
much lower than in the East. The modest additional particulate SO42~ concentrations associated with
urban areas suggests that most particulate SO42~ is regionally distributed, and that IMPROVE and
CSN monitoring sites  can be used together to enhance the ability to delineate particulate SO42~
spatial distributions. For example, note that the additional data from urban sites shown in Figure
9-17 extends north and south of the distribution of the high particulate SO42~ loading shown in
Figure 9-16 over Tennessee and Kentucky, as well as the high loadings over southern Pennsylvania,
eastern West Virginia and northern Virginia. (The color-contour suggested dip in concentrations
between the two  eastern particulate SO42~ high concentrations regions may not exist in the
atmosphere, but this cannot be verified without speciation monitoring sites in southern Ohio, the
border of Kentucky and West Virginia and western Virginia.)
      Urban and remote area carbonaceous PM2.5 are displayed in Figure 9-18 and Figure 9-19
(organic mass), Figure 9-20 and Figure 9-21 (EC), and Figure 9-24  (total carbon = organic + EC
concentration). Just as with particulate nitrate, both organic mass and EC concentrations are more
than twice the remote-area background concentrations for western urban monitoring locations. One
of the more interesting pairing of sites is for the Virgin Islands compared to the urban site at San
Juan, Puerto Rico (see the map cutout Figure 9-18 through Figure 9-21). The San  Juan urban excess
OC is moderate, while the EC value is among the most extreme inferred in this manner. For eastern
urban areas, approximately half the total carbon is local while the other half is regional. In eastern
urban areas, carbonaceous and SO42~ particulate are the two major components of PM2.5, with
roughly equal contributions, and account for over 80% of the mass concentration. Edgerton et al.
(2004, 156413) showed that carbonaceous PM2.5 is responsible for most of the urban excess above
regional concentrations at four urban/rural paired Southeastern Aerosol Research and
Characterization (SEARCH) monitoring sites in the southeastern U.S. However, the higher overall
light extinction efficiency for SO42~ resulting from its hydrophilicity gives it ~ 2:1 dominance in
responsibility for eastern urban light extinction.
      Urban and remote area soil PM2.5 concentrations are displayed in Figure 9-22  and Figure 9-23.
Urban fine  soil concentrations are at most a few tenths of a ug/m higher than the  regional
background concentrations and in some regions they are much less. Just as with carbonaceous PM2 5,
the Virgin Island, San  Juan, Puerto Rico pair are interesting for fine soil. In this case, both of these
island monitoring sites have high concentrations of fine soil, which is caused by the influence of the
trans-Atlantic transport path of dust from Africa (Prospero, 1996, 156889).
      No urban-remote pair of coarse mass concentration maps is available because CSN does not
monitor coarse mass. In Malm et al. (2004, 156728) a map of annual mean coarse mass
concentration is shown for 2003 which includes the values for IMPROVE urban sites, including two
in the western U.S. with much more coarse mass than the nearby remote areas monitoring sites
(i.e., ~24 ug/m3 compared to ~9 ug/m3 for Phoenix, AZ, and ~6 ug/m3 compared to ~2 ug/m3 for
Puget Sound, WA) and one  eastern IMPROVE site at Washington, DC with less coarse mass than the
surrounding remote area values (~2 ug/m3 compared to ~4 ug/m3).
December 2009                                  9-27

-------
       I
    9

*  Alaska
                           Hawaii
                                          IMPROVE Site
                                          IMPROVE Urban Site
        O
Puerto Rico /
Virgin Islands
                                                                               Source: Debell (2006,1563881.

Figure 9-18.    IMPROVE monitored mean organic mass concentrations for 2000-2004.
                                                                                    P12.4
                                                                                    6.47
                                                                                    5.75
                                                                                    5.03
                                                                                    4.31
                                                                                    3.60
                                                                                    2.88
                                                                                    2.16
                                                                                    11.44
                                                                                    0.72
                                                                                    0.00
                                                                                  Mg/m3
                                                                  Puerto Rico/
                                                                  Virgin Islands
               Alaska
                           Hawaii
                                                    A STN Site
                                                    • IMPROVE Site
                                                    • IMPROVE Urban Site
                                                                               Source: Debell (2006,1563881.

Figure 9-19.    IMPROVE and CSN (STN) mean organic mass concentrations for 2000-2004.
December 2009
                                  9-28

-------
             •   Alaska
                            Hawaii
                                                    • IMPROVE Site
                                                    • IMPROVE Urban Site
                                                            0
                                                    Puerto Rico/
                                                    Virgin Islands
                                                                                Source: Debell (2006,1563881.
Figure 9-20.   IMPROVE mean EC concentrations for 2000-2004.
                                                                                     V1.74
                                                                                     0.95
                                                                                     0.84
                                                                                     0.74
                                                                                     0.63
•                                                                                     0.53
                                                                                     0.42
                                                                                     0.32
                                                                                     10.21
                                                                                     0.11
                                                                                     000
                                                                                   (jg/m3
                 _
            °  Alaska
Hawaii
                                                    A STN Site
                                                    • IMPROVE Site
                                                    • Urban IMPROVE Site
      a e
Puerto Rico /
Virgin Islands
                                                                                Source: Debell (2006,156388).
Figure 9-21.    IMPROVE and CSN (STN) mean EC concentrations for 2000-2004.
December 2009
                    9-29

-------
               4
                                 •  •
                                     ..
                                                                                  3.08
                                                                                  144
                                                                                  1.28
                                                                                  1.12
                                                                                  0.96
                                                                                  0.80
                                                                                  0.64
                                                                                  0.48
                                                                                  0.32
                                                                                  0.16
                                                                                  0.00
                                                                                |jg/m3
                                  ,
                                                  • IMPROVE Site
                                                  • IMPROVE Urban Site
                                                                                     O
                                                                             Puerto Rico /
                                                                             Virgin Islands
                                                                              Source: Debell (2006,156388).
Figure 9-22.    IMPROVE mean fine soil concentrations for 2000-2004.
               Alaska
                           Hawaii
                                                  A STN Site
                                                  • IMPROVE Site
                                                  • IMPROVE Urban Site
                               Puerto Rico /
                               Virgin Islands
                                                                              Source: Debell (2006,156388).
Figure 9-23.    IMPROVE and CSN (STN) fine soil concentrations, 2000-2004.

      Figure 9-25 shows the remote area coarse mass concentrations as measured by the IMPROVE
network. The pattern of high coarse mass concentrations from Oklahoma to Iowa is comparable to
the high concentrations in the desert southwest, though as shown in Figure 9-11 it contributes a
December 2009
9-30

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smaller relative share of the light extinction because of the higher contributions to haze by
particulate nitrate and sulfate in this agricultural region of the country. Comparing Figure 9-22 and
Figure 9-25 shows that the coarse mass and fine soil concentration patterns are similar for the desert
southwest but there is a much lower fine soil to coarse mass concentration ratio for the agricultural
center of the country, suggesting a regional difference in the size distribution of the coarse mass,
perhaps due to differences in suspendable soil materials.


9.2.3.4.   Temporal Trends

      Visibility trend analysis requires relatively long data records to avoid having meteorologically
driven interannual variability obscure more meaningful  emissions-driven air quality trends. A
requirement for long-term data limits the number of monitoring sites useful for trend analysis. Maps
that show haze trends for IMPROVE sites for the 10-year period 1995-2004 for the mean of the 20%
best and the 20% worst haze days where sites are required to have a minimum of 6 complete years of
data during the  10-year period are shown in Figure 9-26 and Figure 9-27, respectively. The best haze
days have improving haze at most sites (32 of 47), no trend at several sites (10 of 47) and degrading
visibility at just one site (Great Sand Dunes, CO). The worst haze days have improving haze
conditions at  several sites (13 of 47), no trend at most sites (30 of 47), and degrading visibility at a
few western sites (4 of 47).
December 2009                                  9-31

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                              Nitrates
                                                                          Sulfates
Fresno
Missoula

Salt Lake City
Tulsa
St. Louis
Birmingham
Indianapolis
Atlanta
Cleveland
Charlotte
Richmond
Baltimore
New York City
I
13
\ \
j — i
[ WEST
	 U E^7

	 1
~^H
~|
| |
3D
— I — i n Regional
Contribution
— 1 	 1 • Local
Contribution
| |
i i i i i i i i i i i i
1 2 4 6 8 10 12
Fresno
Missoula

Salt Lake City
Tulsa
St Louis
Birmingham
Indianapolis
Atlanta
Cleveland
Charlotte
Richmond
Baltimore
New York City
(
I I
|
— i — i
| | WEST
I I EAST


3
II
I
II
ID Regional
Contribution
D Local
|
I 2 4 6 8 10 12
                     Annual Average Concentration
                          of Nitrates, ug/m3
                  Annual Average Concentration
                       of Sulfates, ug/m3
                                                   Carbon
Fresno
Missoula
Salt Lake City
Tulsa
St. Louis
Birmingham
Indianapolis
Atlanta
Cleveland
Charlotte
Richmond
Baltimore
New York City


WEST
EAST






i n Regional
1 Contribution
FJ Local
Contribution

                                          2     4     6     8    10    12
                                          Annual Average Concentration
                                                of Carbon,
                                                                                Source: U.S. EPA (2004, 1902191
Figure 9-24.   Regional and local contributions to annual average PM2.s by particulate S042~,
               nitrate and total carbon (i.e., organic plus EC) for select urban areas based on
               paired IMPROVE and CSN monitoring sites.
December 2009
9-32

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                                                    IMPROVE Site
                                                    IMPROVE Urban Site
                                                                                   e
                                                                            Puerto Rico /
                                                                            Virgin Islands
                                                                            Source: Debell (2006,1563881.

Figure 9-25.   IMPROVE mean coarse mass concentrations for 2000-2004.

      Eight-, ten-, and sixteen-year trends analysis conducted for the Western Regional Air
Partnership (WRAP) as part of the Causes of Haze Assessment (http ://www. wrapair. or) show that
improving trends for the 20% best haze days for the sites in the western U.S.  generally correspond to
improving trends for all of the major components with the exception of parti culate nitrate. Trends
assessment for the worst haze days at western  sites show consistent reductions in parti culate SO42~,
but otherwise have mixed increasing and decreasing haze component trends,  many of which are not
statistically significant. Substantial interannual and shorter term spatial and temporal wildfire
activity variations have been shown to have a significant impact on the variability of haze in the
western U.S. (Park et al., 2006, 190469: Spracklen et al., 2007, 190485). Edgerton et al. (2004,
156413) showed a decreasing trend in PM2.5 of about 18% (corresponding to  1 ug/m3 to 2 ug/m3) for
4 urban-rural paired SEARCH sites in the Southeastern U.S. corresponding to similar reductions in
SO42~ and carbonaceous particulate.
December 2009
9-33

-------
                f-.
                                                         * Improving Trend, p<-0.05

                                                           Improving Trend, G.05
-------
               r/:	


                                                * Improving irend,D<=005

                                                  Improving Trend, 0 05
-------
atmospheric ammonia or elevated temperatures, trends in nitrogen may be principally in nitric acid
with no net change in nitrate light extinction. Alternately with abundant ammonia and low
temperatures the trend in nitrogen may be principally in particulate nitrate and the nitrate component
of haze.
                  Western US
                 North Eastern US
                                       1.38
                                     - 1.15
                                            in
                                     -0.92  in
                                     - 0.69
                                            LLJ
                                            CN
                                            O
                                            V)
                                       0.46
                                         16.2
                                                                                     -  13.5
                                                                                       10.8  in
                                              o
                                              'i/i
                                              ui
                                              E
                                              LU
                                              c*j
                                              O
                                              U)
       1988  1990 1992  1994  1996 1998
                                                     1988  1990  1992  1994  1996  1998
               South Middle US
                 South Eastern US
                                       1.83
                                       0.61
      1988  1990  1992  1994  1996  1998

                                -*— Sulfate Ion
                                                «~ 7.5

                                                 "Si
                                                 w 4.5
                                        6.75
                                                                                      5.625
                                                                                      4.5
                                        3.375  E

                                              O
                                              CO

                                        2.25
        1988  1990  1992  1994  1996 1998

     SO2 Emissions
                                       Source: Reprinted with Permission of the American Geophysical Union from Malm et al. (2002,1567271.

Figure 9-28.    Ten-year trends in the 80th percentile particulate S042" concentration based on
               IMPROVE and CASTNet monitoring and net S02 emissions from the National
               Emissions Trends (NET) data base by region of the U.S.

      Ten-year trends (1994-2003) of particulate nitrate contribution to light extinction during the
20% worst haze conditions conducted as part of the Causes of Haze Assessment (see the link in
Table 9-1) are shown in Figure 9-29. This indicates that haze from particulate nitrates is increasing
across the western U.S.  at a rate of several Mm"1 per year in parts of California and at a rate of
several tenths of an Mm"1  across the Four-Corners states. A similar particulate nitrate trends map (not
shown here) for the 20% best haze conditions that is available at the same web site shows decreasing
particulate nitrate contribution to light extinction at nearly all of the western monitoring sites. While
statistically significant, these trends for both the 20% worst and 20% best haze periods are
influenced by an unexplained nationwide period of depressed nitrate  concentrations  measured by the
IMPROVE network during a 4-yr period from the winter of 1996-1997 through the winter of
2000-2001. Extensive examinations of plausible monitoring methodological explanations have failed
December 2009
9-36

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to offer any evidence that the data are invalid (McDade, 2004, 192075). but no satisfactory
atmospheric or emissions-related explanation has been offered to account for this 4-yr depression of
nitrate. Similar analyses of particulate nitrate haze trends are not available for the rest of the country.
      Maps of remote-area 8-, 10-, and 16-yr trends for carbonaceous and crustal PM species based
on IMPROVE monitoring are available for the western U.S. conducted as part of the Causes of Haze
Assessment. Generally these show a broad range of results (i.e., a mixture of statistically significant
upward or downward trends and insignificant trends often with neighboring sites having opposing
trends) that vary considerably depending on the number of years selected (i.e., 8, 10, or 16) and
whether trends are for the best,  worst, or middle of the haze distribution data. The scatter in these
results is undoubtedly due to the high interannual variability and varying locations of wildfire and
wind-suspended dust emissions that dominate the remote-area concentrations of the carbonaceous
and crustal PM species in the western U.S.
                  ft        t

              ft
                t      *      *        *
              A
                         A          f                                      Legend
                 t
               n
A  4                                         ,  WNSIope
ft  "  "   '
    A$  ^                      i               ;  ft  0.064-0,093

                                                I)1  0.094 -

                                                'ft  0.171 -


                                                '(V  0.521 -
                                  .                      .                   f]1 0.094-0170
                                  If
                                                                             0.171 - 0.520


                                                                                 1509
                                                                           ^h 1.510-5089


                                                                          WNPValue

                                                                           I 0.21-1.00

                                                                             0.11 -0.20

                                                                             0.06-0.10

                                                                           • 0.00 - 0.05
                                                                             Source: http://wvwv.coha.dri.edu/
Figure 9-29.    Map of 10-yr trends (1994-2003) in haze by participate nitrate contribution to haze
               for the worst 20% annual haze periods. The orientation, size and color of the
               arrows indicate the direction, magnitude and statistical level of significance of
               the trends. These consistent upward trends may be a misleading result due to an
               unexplained sampling issue (see text for additional information).
9.2.3.5.   Causes of Haze
      In order to attribute haze to emissions from individual sources, source types, or source regions,
generally, any of a number of receptor and air quality simulation modeling approaches are applied.
When using multiple approaches, the results of each are reconciled using a weight-of-evidence
methodology. Commonly this methodology has been applied to the extensive datasets generated by
special studies designed to estimate source-receptor relationships for a few receptor locations or for
individual emission sources (Pitchford et al., 1999, 156873: Pitchford et al., 2005, 156874: Schichtel
December 2009                                  9-37

-------
et al., 2005, 156957). More recently the Regional Planning Organizations (RPOs) have sponsored
extensive regional haze source attribution assessments using weight-of-evidence methodologies to
reconcile attribution results for virtually all of the remote-area IMPROVE sites to support the
development of State Implementation Plans for the RHR. Additionally, a number of recent urban
special studies, including those sponsored by EPA PM Supersites program (Solomon  and Hopke,
2008, 156997). have addressed the causes of and sources contributing to urban excess PM
concentrations above region concentrations. Attribution results uncertainties are generally larger than
those of the measurements upon which they are based because they also include model uncertainties
and assumptions, as well as issues of representativeness (e.g., How well does the data used in the
analysis represent the typical emissions, air quality and meteorological conditions of interest?). As
such it is advisable to treat the attribution results reported below as semi-quantitative.
      The relative importance of the PM species that contribute to  haze varies by region of the U.S.
and time of year as shown in Figure 9-9, Figure 9-10, and Figure 9-11, above. Generally haze in the
western half of the  U.S. is not dominated by any one or two PM  species. In  the eastern half of the
U.S., SO42~, especially during summer, and nitrate during the winter in the Midwest are the dominant
haze species. As described above, urban haze can be viewed as a composite of the regional and local
contributions where local contributions seem to be dominated by carbonaceous and, to a lesser
extent, nitrate and crustal PM components. There have been far fewer urban investigations that
explicitly consider  visibility impacts, though there are numerous studies of urban PM source
attribution. The order of discussion below on the cause of haze is by region  beginning in the western
U.S. and proceeding to the east, analogous to  dominant air flow patterns across the  lower 48 states
and will include information  from urban studies along side those of remote-area haze investigations.
      Based on modeling of an episode (September 23-25,  1996) in the California South Coast Air
Basin (SCAB) and  another episode (January 4-6, 1996) in the San Joaquin Valley (SJV) by Ying and
Kleeman (2006, 098359), about 80% of the particulate SO42~ for both regions is from upwind
sources (i.e., likely from offshore sources including marine shipping, long-range transport and
natural marine sources), with most of the remaining is associated with diesel and high-sulfur fuel
combustion. Kleeman et al. (1999, 011286). using a combination of measurements and modeling,
showed that the upwind particulate SO4Z~ source region for the SCAB was over the  Pacific Ocean
(confirmed by measurements on Santa Catalina Island) and that these particles subsequently grew
with accumulation  of additional secondary aerosol material, principally ammonium nitrate as  they
traversed the SCAB. The majority of the nitric acid that forms particulate nitrate in  the SCAB is
from diesel and gasoline combustion (-63%), while much of the ammonia is from agricultural
sources (-40%), catalyst equipped gasoline combustion (-16%), and upwind sources (-18%). The
majority of the OC found in SCAB was attributed in this study to primary emissions by
transportation-related sources, including diesel (-13%) and gasoline (-44%) engines and paved road
dust (-12%). At the Fullerton site in the middle of the SCAB the concentration of locally generated
organics is roughly double that of the locally generated nitrates (-5.6 ug/m3 compared to
-2.4 ug/m3), while  at Riverside on the east edge of the SCAB and near the large agricultural sources
of ammonia emissions, the particulate nitrate concentrations are nearly double that of organic PM
(-17 ug/m3 compared to -10 ug/m3).
      Ying and Kleeman (2006,  098359) showed that during the winter 1996 episode in the SJV
most of the nitric acid that forms particulate nitrate is from upwind sources  (-57%) with diesel and
gasoline combustion contributing most of the rest  (30%), while much of the ammonia is from
upwind sources (-39%) and a combination of area, soil and fertilizer sources (-52%). In an
assessment of PM particle size and composition in the SJV during the winter of 2000-2001, Herner
et al. (2006, 135981) showed that fresh emissions  of carbonaceous PM from combustion sources in
urban locations (Sacramento, Modesto, and Bakersfield, CA) move quickly from ultrafme particle
size (i.e., diameter -0.1 um) to accumulation mode by condensation with accumulation mode
(i.e., diameter -0.5  um) particles, and that secondary nitrate particle formation occurs preferentially
on the surface of hydrated ammonium sulfate particles during the afternoon when gas-phase nitric
acid is at peak photo-chemical production from NOX. Given the abundance  of ammonia emissions
and low ambient temperatures, particulate nitrate production in this way is only limited by the
availability of nitric acid. Due to the cool winter conditions there was little SOA production during
this study.  Sea salt was shown to dominate the larger coarse particle mode during on-shore wind at
the background coastal monitoring site at Bodega Bay, north of San Francisco, CA.
      Using a regression analysis to find the dependence of particulate SO42~ concentration
measured over a 3-year period (2000-2002) at 84 western IMPROVE monitoring sites on the
December 2009                                 9-38

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modeled transport trajectories to the sites for each sample period, Xu et al. (2006, 102706) were able
to infer the source regions that supplied particulate SO42~ in the western U.S. Among the source
regions included in this analysis was the near coastal Pacific Ocean (i.e., a 300-km zone off the coast
of California, Oregon, and Washington). Up to half of the parti culate SO42~ measured at Southern
California monitoring sites was associated with this source region.  As shown in Figure 9-30 the zone
of impact from this source region included large regions of California, Arizona, and Nevada. The
authors made the case that high sulfur content fuel used in marine shipping and port emissions may
be largely responsible. As a result, the WRAP RPO emissions inventory was modified to include
marine snipping and a Pacific Offshore source region was added to source attribution by air quality
simulation modeling.
      The SO42~ attribution results of the WRAP air quality modeling (results available on the
Technical  Support System (TSS) website, see Table 9-1 for the web-link) credit the Pacific offshore
source region with somewhat smaller contributions than those from the trajectory regression work by
Xu et al. (2006, 102706) with concentrations at the peak impact site in California that are about 45%
compared to 50% by regressions and even greater differences for more distant monitoring sites.
Based on the modeling attribution the Pacific offshore source region was responsible for 10-20% of
the nitrate measured in Southern California.
                                               Contribution of the Pacific Coast to Siilntc Concentration
                                                            0.1-0.2
                                                            0.2-0.4
                                                            0.4-0.6
                                                            0.6-0.8
                                                            0.8 - 1 .4
                                            Source: Reprinted with Permission of Atmospheric Environment from Xu et al. (2006,1027061.
Figure 9-30.
Contributions of the Pacific Coast area to the ammonium sulfate (ug/m3) at 84
remote-area monitoring sites in western U.S. based on trajectory regression for
all sample periods from 2000-2002 (dots denote locations of the IMPROVE
aerosol monitoring sites).
      A coordinated effort by federal, state, and county air quality organizations to determine the
causes of haze in the Columbia River Gorge (a deep and narrow gap in the Cascade Mountains on
the Washington/Oregon border) through extensive multiyear measurements and high spatial
resolution air quality modeling of typical episodes demonstrated the multitude of emission sources
that contribute to its impairment (Pitchford et al., 2007, 098066). During the summer, gorge winds
are generally from the west and relatively dry. More than half of the haze during a typical summer
episode is from a combination of international and other distant sources (-22% at the western end of
the gorge) plus regional natural sources including wildfire and secondary organic PM from biogenic
emissions (-39% at the eastern end of the gorge). The Portland/Vancouver metropolitan area was
responsible for a significant amount of the haze during the summer  (-20% on in the western end of
December 2009
                               9-39

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the gorge), while sources within the gorge were responsible for a moderate amount of haze (-6% and
-9% at the western and eastern ends of the gorge). The wind is much more often from the east
during the winter. The highest haze conditions in the gorge are during the winter and are associated
with fog conditions that rapidly convert precursor gaseous emissions of NOX and SO2 from local and
regional combustion sources and NH4 from local and regional agricultural activities to secondary
nitrate and SO42~ PM that persist as a post-fog intense haze. Contributions by these sources east of
the gorge contribute -57% of the haze on the eastern end of the gorge, with half of the nitrate and
SO4 ~ particulate from electric utility emissions  and most of the rest from transportation sources.
Other sources contributing during the winter haze at the eastern end of the gorge are from sources
outside the modeling domain (i.e., most of Washington and Oregon) and within the gorge (-23% and
-10%, respectively).
      An assessment of concurrent measurements at the nearby Mt. Hood IMPROVE monitoring
site (45 km south of the Columbia River at 1,531 m ASL) shows that Columbia River Gorge haze
conditions and especially the wintertime high nitrate/SO42~ contributions to haze are not typical of
the generally higher elevation  remote areas of the region (Pitchford et al., 2007, 098066). However
Gorge-like high wintertime nitrate and SO42~ are found at the Hells Canyon IMPROVE site, which is
similarly situated in a narrow canyon of the Snake River almost 400 km east of the Gorge (from the
VIEWS web site, see Table 9-1), implying that there may be a substantial vertical concentration
gradient during winter in this complex terrain.
      Several example monitoring locations distributed across the northern and southern portions of
the western U.S.  have been selected to illustrate the attribution results from the WRAP-sponsored
attribution analysis tools that estimate the relative responsibility for haze of the various PM species
by source region and source type. The selected sites include Olympic NP, WA; Yellowstone NP, WY;
and Badlands NP, SD across the north, and San  Gorgonio Wilderness (W), CA; Grand Canyon NP,
AZ and Salt Creek W, NM across the south as shown in Figure 9-31.
December 2009                                 9-40

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      2000-2004 Baseline Average
          20% Worst Days
   IMPROVE Aerosol Extinction (Mrn-1)

    
-------
area and wildfire emissions contributing from a few percent at the furthest eastern sites to about half
at San Gorgonio.
      By comparison, the particulate nitrate is much more from domestic regional emission sources,
with -60-80% being from emissions within the WRAP region. For the west coast sites about 25% of
the nitrate is from a combination of Pacific offshore emissions (i.e., marine shipping) and outside
domain regions. Canadian emissions are responsible for about 10-30% of the particulate nitrate for
the three northern sites, but Mexican emissions do not contribute appreciably to particulate nitrate
for the three southern sites.  Motor vehicles are the largest contributing NOX source category
responsible for particulate nitrate for these six WRAP sites, with a combination of point,  area and
wildfire source categories also contributing from about 10-50% of the WRAP regional emissions.
      WRAP only used the virtual tracer approach to investigate source locations and categories for
SO2 and NOX emissions. A different type of virtual tracer modeling tool was used to track the
various OC compounds and sort them into three  groups for 2002. The first group labeled primary
organics includes all of the organics that are emitted directly as PM from any source type and
location. The second group  labeled anthropogenic secondary organics is PM produced in the
atmosphere by aromatic VOCs. The third  category labeled biogenic secondary organics is PM
produced in the atmosphere by biogenic VOCs. Organic PM in the biogenic secondary category
includes those that would functionally be considered man-made emissions (e.g., those from
agricultural crops and urban landscapes), though in most remote areas of the west these man-made
VOC  emissions are  small compared to those of the natural biogenic sources. Figure 9-33, Figure
9-34,  and Figure 9-35  show the monthly averaged apportionment of organic PM for the 6 selected
monitoring locations.
December 2009                                  9-42

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         Olympic NP
             2002
          Sulfate 1.1 ua/m3
Yellowstone NP




      '2002
   Sulfate0.6ua/m3
Bad
NP
       San Gorgon 10 W   Grand Canyon NP
      D02
  Sulfate 1.2 uo/m3
                    Salt Creek W

             2002
          Sulfate 0.8 ua/m3
       \^l


     2002
  Sulfate 0.5 uci/m3
     2002
  Sulfate 1.4 ua/m3
        (a)

  WRAP

D Pacific Off shore

  CENRAP

  Eastern U.S.

 JCanada

  Mexico

  Outside Domain
         Olympic NP
Yellowstone NP

 Badlands NP
                                               V
             2002                 2002                 2002
         Nitrate 1.6 ua/m3        Nitrate 0.6 ua/m3         Nitrate 1.2 ua/m3

                                                \
       San Gorgonio W     Grand Canyon NP     Salt Creek W
                (b)


            WRAP

            Pacific Offshore

            CENRAP

            Eastern U.S.

         D Canada

            Mexico

            Outside Domain
              2002
          Nitrate 1.5 uo/m3
       2002
   Nitrate 0.4 ua/m3
     2002
  Nitrate 0.5 ua/m3
Figure 9-32.   Particulate $(>42~ (a) and nitrate (b) source attribution by region using CAMx
             modeling for six western remote area monitoring sites : top left to right Olympic
             NP, WA; Yellowstone NP, WY; Badlands NP, SD; bottom left to right San Gorgonio
             W, CA; Grand Canyon NP, AZ; and Salt Creek W, NM. WRAP includes ND, SD, WY,
             CO, NM and all states further west. CENRAP includes all states east of WRAP and
             west of the Mississippi River including MN. Eastern U.S. includes all states east
             of CENRAP. The Pacific Offshore extends 300km to the west of CA, OR, and WA.
             Outside Domain refers to the modeling domain, which extend hundreds of
             kilometers into the Pacific and Atlantic Oceans and from Hudson Bay Canada to
             just north of Mexico City. This figure was assembled from site-specific diagrams
             produced on the TSS web site  (see Table 9-1) for 2002.
December 2009
               9-43

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                                   Organic Aerosol for All Days
                                     Class I Area - Olympic NP, WA
     3.20
                                   Organic Aerosol for All Days
                            Class I Areas - San Gorgonio W, CA: San Jacinto W, CA
     2.80
                                                                   Source: From the TSS website, see Table 9-1.
Figure 9-33.
Monthly averaged model predicted organic mass concentration apportioned into
primary PM and anthropogenic and biogenic secondary PM categories for the
Olympic NP (top) and San Gorgonio W (bottom) monitoring sites.
      Based on the modeling results for these six sites and confirmed by measurements (see, e.g.,
Figure 9-10), a west-to-east decreasing gradient of organic mass exists with annual concentrations
from -2 ug/m3 for the coastal state sites to ~1 ug/m3 for the intermountain west sites, to <1 ug/m3 for
the sites just east of the Rocky Mountains, discounting the large fire impacts for July at Yellowstone
NP which raised its annual mean to -2  ug/m3. At all of these remote-area sites anthropogenic
secondary PM is estimated to be a small fraction of the organic mass, with the largest fractional
contribution at the San Gorgonio monitoring site immediately downwind of the major Southern
California urban areas, yet having <10% of the monthly mean organic mass from anthropogenic
secondary PM. Of the six selected monitoring sites, San Gorgonio has the highest fraction of the
organic PM from primary emissions (-57%), followed by Yellowstone (-55%), then the two
eastern-most sites (Badlands -42% and Salt Creek 41%), and with Grand Canyon and Olympic NPs
the lowest fraction by primary emissions (-37%). Yellowstone NP would have had the lowest
fraction of organic PM by primary emissions had it not been for the month of July (the 11-mo mean
was 29%) when wild fire smoke contributed. Results from recent chamber and field studies, and
modeling would seem to call into question apportionment of primary and secondary carbon done by
traditional air quality model simulations of OC, as described above, due to the combined effects of
December 2009
                              9-44

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extensive evaporation of semivolatile primary emissions when diluted and to photochemical

reactions of low volatility gas phase species that substantially increases the amount of secondary

organic PM (Robinson et al., 2007, 191975).
     14.00



     12.00



   J= 10.00

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-------
     0.80
                                    Organic Aerosol for All Days
                                     Class I Area - Badlands NP, 3D
     1.20
     1.00
                                    Organic Aerosol for All Days
                                   Class I Area - Salt Creek NVVRW, NM
                                                                    Source: From the TSS website, see Table 9-1.
Figure 9-35.
Monthly averaged model predicted organic mass concentration apportioned into
primary PM and anthropogenic and biogenic secondary PM categories for the
Badland NP (top) and Salt Creek W (bottom) monitoring sites.
      Radiocarbon (14C) dating techniques were used to group ambient PM carbon into fossil and
contemporary source categories at 12 IMPROVE monitoring sites across the U.S., 8 of which are in
the WRAP region (Schichtel et al., 2008, 156958). Results of this work showed that contemporary
carbon accounts for about half the carbon in urban areas, 70-97% in near-urban areas (i.e., San
Gorgonio) and 82-100% in remote areas. Comparing these radiocarbon dating results with the
WRAP virtual tracer modeling results for organic aerosol (above), and presuming that the modeled
anthropogenic secondary organic is fossil carbon and the biogenic secondary is  contemporary
carbon, suggests that a large fraction of the model-determined regional primary organic PM is from
contemporary carbon sources (e.g., smoke from wildfires).
      Schichtel et al. (2008, 156958) compared radiocarbon measurements at two sets of urban/rural
paired sites in the west (Mount Rainer/Seattle, and Tonto/Phoenix). Figure 9-36 shows that most of
total carbon urban excess (i.e., urban site concentration minus the regional site concentration) in the
summer is from fossil carbon sources (87% and 79%, respectively), while in the winter there is a
surprisingly high fraction of the urban excess at both sites that is from contemporary carbon sources
(41% and 47%, respectively). This implies that urban,  and therefore anthropogenic, activities
December 2009
                              9-46

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generate almost as much PM2.5 carbon from contemporary sources (e.g., residential wood
combustion) as from the fossil sources during the winter for these two western urban areas.


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         < 0.4S t 0.11
                 Phoenix Tonto
                 0.49    0.71
                 O     O
Figure 9-37.   Average contemporary fraction of PM2.s carbon for the summer (top) and winter
              (bottom), estimated from IMPROVE monitoring data (June 2004-February 2006)
              based on EC/TC ratios. The contemporary values from radiocarbon dating for the
              12 monitoring sites are indicated in by colored circles with the site names. Color
              contours are shown to aid in showing sites with similar values. Site locations are
              indicated by circles for remote area sites and triangles for urban sites.
December 2009
                                         9-48

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      Contemporary carbon estimates for all of the IMPROVE network monitoring sites for data
from two summer seasons (June, July and August, 2004/2005) and two winter seasons (December,
2004/2005, January and February, 2005/2006) were calculated from the measured EC to total carbon
(EC/TC) ratios using the 12-site empirical relationship between radiocarbon determined
contemporary carbon fraction and IMPROVE measured EC/TC ratio (Schichtel et al., 2008,
156958). The results are displayed in color contour maps in Figure 9-37, which also shows the
radiocarbon determined contemporary carbon for the 12 sites. The lowest contemporary carbon
estimates (<60%) in both seasons are for urban areas. In the rural West, most of the sites have over
90% of their PM carbon from contemporary carbon sources during the summer and from 60% to
over 90% during the winter. In the rural East, most of the sites have 45-90% of their PM carbon  from
contemporary carbon sources during the summer and from 60% to over 90% in the winter.
      Schichtel et al. (2008, 156958) showed a strong relationship between the site-averaged EC/TC
ratios and the site-averaged fraction of fossil carbon separately for the summer and winter data sets
(i.e., R2 of 0.71  and 0.87, respectively). Using regression analysis  they estimated that the summer
and winter EC/TC ratios associated with purely fossil carbon were 0.35 ± 0.039 and 0.46 ± 0.028,
respectively, and for purely contemporary carbon the EC/TC ratios were 0.12 ± 0.011 and
0.19 ± 0.0095. These ratios are shown to be consistent with corresponding ratios from the literature
for source testing primary fossil and contemporary combustion sources respectively. They are also
shown to be consistent with the 90 percentile value of the EC/TC ratio from the urban IMPROVE
monitoring sites (0.41 and 0.44 for summer and winter) and the 10th percentile values of the EC/TC
ratio for remote areas IMPROVE monitoring sites (0.07 and 0.16 for summer and winter), which
they argue are dominated by fossil and contemporary carbon,  respectively.
      The largest sources of contemporary carbon are primary emissions from biomass burning  and
SOAfrom biogenic precursor gases  (e.g., terpenes from conifer forests).  Schichtel et al. (2008,
156958) estimated the 12-site overall contribution by secondary organic PM to the summer
contemporary carbon fraction as 36 ± 6.4% by assuming the EC/TC ratio for contemporary carbon
during the winter represented the ratio of primary emissions only (i.e., no secondary organic PM
formation in the winter) and that the EC/TC ratio for primary  emissions is independent  of seasons.
This approach should provide a lower bound estimate of the secondary OC species. The same
method applied to the fossil carbon fraction yielded an estimate of 23 ±  10% of the fossil carbon PM
from secondary organic formation in the atmosphere during the summer. These estimates correspond
to over 40% of the contemporary and over 35% of the fossil OC being from secondary  PM
formation.
December 2009                                 9-49

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       100.00


       90.00


       30.00


       70.00


       60.00


       50.00


       40.00
                Sources and Areas of Potential Organic Carbon Emissions on Worst 20% Visibility Days
                                          Class I Area - Olympic NP, WA
       30.00

       20.00
       10.00


        0.00
     WRAPTSS- 3O1MIE
      70.00
      60.00
               Sources and Areas of Potential Elemental Carbon Emissions on Worst 20% Visibility Days
              	   Class I Area-Olympic NP.WA
     • WBDust

       Fugitive Dust
| Road Dust

 Off-Road Mobile
| On-Road Mobile

 Off-Shore
] WRAP Area Q&G    Biogenic    | Anthro Fire

JArea             Natural Fire  | Point

                     Source: From the TSS website (see Table 9-1)
Figure 9-38.   Results of the weighted emissions potential tool applied to primary OC emissions
               (top) and EC emissions (bottom) for the baseline and projected 2018 emissions
               inventories for Olympic NP. Only source regions (WRAP states and other
               regions) with the largest estimated contributions are shown (i.e., Canada,
               Oregon, Pacific Off-Shore, and Washington from left to right). The scale is
               normalized (i.e., unitless) one over distance weighted emissions multiplied by
               trajectory residence time.
December 2009
                           9-50

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             Sources and Areas of Potential Organic Carbon Emissions on Worst 20% Visibility Days
                               Class I Areas - San Gorgonio W, CA: San Jacinto W, CA
               CA - 2000-04
                                     2018PRP
                                                         PO - 2000-04
                                                                                2018 PRP
            Sources and Areas of Potential Elemental Carbon Emissions on Worst 20% Visibility Days
                                Class I Areas - San Gorgonio W, CA: San Jacinto W, CA
               CA - 2000-04
                                     2018 PRP
                                                         PO - 2000-04
                                                                                2018 PRP
 •WBDust

 D Fugitive Dust



Figure 9-39.
Road Dust       | On-Road Mobile  Q WRAP Area O&G

Off-Road Mobile     Off-Shore       []Area
                                                                     Biogenic    • Antrim Fire

                                                                     Natural Fire | Point

                                                                      Source: From the TSS website (see Table 9-1).
               Results of the weighted emissions potential tool applied to primary OC emissions
               (top) and EC emissions (bottom) for the baseline and projected 2018 emissions
               inventories for San Gorgonio W. Only source regions (WRAP states and other
               regions) with the largest estimated contributions are shown  (i.e., California and
               Pacific Off-Shore from  left to right). The scale is normalized (i.e., unitless) one
               over distance weighted emissions multiplied by trajectory residence time.
December 2009
                            9-51

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     WRAP applied a weighted emissions potential analysis tool that combined gridded emissions data with back-trajectory analysis that simulated the transport pathway to the
various monitoring sites to infer likely source region and emission categories for the 20% best and 20% worst haze conditions for each of the IMPROVEPMspeciation monitoring
    locations in the West. Unlike the virtual tracer approach that uses a full regional air quality simulation model, this method does not explicitly account for chemistry or removal
 processes and it does not incorporate the sophisticated dispersion estimates (i.e., it uses one over distance weighting for dispersion), so it should be considered a screening tool
  that has been found to be helpful in identifying the likely sources contributing to haze. More information on this approach is available elsewhere (see the link to the TSS in Table
9-1). Primary OC and EC PM species results from the weighted emissions potential tool for the worst 20% haze days using the 2000-2004 base years' emissions and trajectories,
    and the same trajectories with 2018-projected emissions for each of the 6 selected western monitoring locations are shown in Source: From the TSS website (see Table 9-1)
      Figure 9-38 through Figure 9-43.
                                                                  For Olympic NP (Source: From the TSS website (see Table 9-1)
      Figure 9-38), most of the primary OC  as well as most of the EC PM is likely to be from the
state of Washington during the worst haze days. This is because the multi-day trajectories that
transport emissions on its worst days tend to be short (within  200 km based on  maps  available on
TSS, see Table 9-1). Area sources, which include emissions from residential wood heating,
watercraft, non-mobile urban and other sources too small to be labeled as point sources, are the big
contributors to primary organic, while on- and off-road mobile emissions plus area sources are large
contributors to the  EC at Olympic NP. The 2018 projected growth in area sources and decrease in
emissions of mobile source emissions is  anticipated to increase the haze by primary OC while
reducing the haze by EC at Olympic NP  The same analysis applied to San Gorgonio (Figure  9-39), is
similar in that the majority of the emissions with the potential to contribute to primary OC and EC
PM is from the home state, California in this case. However, the likely importance of natural fire
emissions for carbonaceous PM species sites is substantially greater at San Gorgonio W. than it was
for Olympic NP.
      The weighted emissions potential results applied to Yellowstone NP and  Grand Canyon NP
(Figure 9-40 and Figure 9-41) show the likely dominance of natural fire emissions in the
intermountain western U.S. to primary OC and EC PM during worst haze conditions  for these two
locations. Numerous states have emissions that have the potential to contribute noticeably to these
carbonaceous species, due to relatively long multi-day trajectories (500-1,000 km) on worst haze
days, though for both sites the home state has the greatest potential based on this inverse distance
weighting approach.  On- and off-road mobile sources in Arizona and California have significant
potential to contribute to Grand Canyon carbonaceous particles,  especially  EC  concentrations,
probably due to some of the trajectories being over the  populated areas  of these two states to the
south and southwest of Grand Canyon.
December 2009                                      9-52

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Sources and Areas of Potential Organic Carbon Emissions on Worst 20% Visibilty Days
Class 1 Areas - Grand Teton NP, WY: Red Rock Lakes NVVRVV, MT: Teton W, VW: Yellowstone NP, WY




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  • - ^ 0 =• | | Sources and Areas of Potential Elemental Carbon Emissions on Worst 20% Visibility Days Class I Areas - Grand Teton NP, VW: Red Rock Lakes NWRVV, MT: Teton W, WY: Yellowstone NP, WY •*r o_ ^_ -^™ ff ^— ^— Q_ ^^ I— ^ •^-Q_T3-Q_-^-Q_^-Q_ ^m •ft ^= ^^ CL ™* • PTSS-M10& WBDust Fugitive Dust Q • Road Dust Off-Road Mobile i— 5 | On-Road Mobile Off-Shore i— •WRAP Area OSG DArea 1 Biogenic Natural Fire | | Anthro Fire • Point Source: From the TSS website (see Table 9-1). Figure 9-40. Results of the weighted emissions potential tool applied to primary OC emissions (top) and EC emissions (bottom) for the baseline and projected 2018 emissions inventories for Yellowstone NP. Only source regions (WRAP states and other regions) with the largest estimated contributions are shown (i.e., California, Idaho, Montana, Oregon, Utah, Washington, and Wyoming from left to right). The scale is normalized (i.e., unitless) one over distance weighted emissions multiplied by trajectory residence time. December 2009 9-53

  • -------
          BO.00
                   Sources and Areas of Potential Organic Carbon Emissions on Worst 20% Visibility Days
                                           Class I Area - Grand Canyon NP, AZ
          50.00
          40.00
          30.00
          20.00
          10.00
          0.00
    
                  Sources and Areas of Potential Elemental Carbon Emissions on Worst 20% Visibility Days
                                           Class I Area - Grand Canyon NP, AZ
          50.00
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    •WBDust      • Road Dust      | On-Road Mobile  QwRAP Area OSG   Biogenic
    
    DFugitive Dust     Off-Road Mobile   ^Off-Shore      DArea            Natural Fire
    
                                                                      Source: From the TSS website (see Table 9-1).
                                                                                   | Anthro Fire
    
                                                                                   I Point
    Figure 9-41.    Results of the weighted emissions potential tool applied to primary OC emissions
                   (top) and EC emissions (bottom) for the baseline and projected 2018 emissions
                   inventories for Grand Canyon NP.  Only source regions (WRAP states and other
                   regions) with the largest estimated contributions are shown (i.e., Arizona,
                   California, Mexico, New Mexico, Nevada, Oregon, Pacific Off-shore and Utah from
                   left to right).  The scale  is normalized (i.e., unitless) one over distance weighted
                   emissions multiplied by trajectory residence time.
    December 2009
                                              9-54
    

    -------
         30.00
                  Sources and Areas of Potential Organic Carbon Emissions on Worst 20% Visibility Days
                                         Class I Area - Badlands NP, SD
    WRAP Tss-aaimE o ^ uj
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    Sources and Areas of Potential Elemental Carbon Emissions on Worst 20% Visibility Days
    Class I Area - Badlands NP, SD
    
    
    
    
    
    
    
    
    
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                                                                      Source: From the TSS website (see Table 9-1).
    
    Figure 9-42.   Results of the weighted emissions potential tool applied to primary OC emissions
                  (top) and EC emissions (bottom) for the baseline and projected 2018 emissions
                  inventories for Badlands NP. Only source regions (WRAP states and other
                  regions) with the largest estimated contributions are shown (i.e., Arizona,
                  California, Canada, CenRAP, Colorado, eastern U.S., Idaho, Montana, North
                  Dakota, Nevada, Oregon, South Dakota, Utah, Washington, and Wyoming from
                  left to right). The scale is normalized (i.e., unitless) one over distance weighted
                  emissions multiplied by trajectory residence time.
    December 2009
    9-55
    

    -------
                   Sources and Areas of Potential Organic Carbon Emissions on Worst 20% Visibility Days
                                          Class I Area - Salt Creek NVVRVV, NM
          40.00
    
    
          36.00
          36.00
                  Sources and Areas of Potential Elemental Carbon Emissions on Worst 20% Visibility Days
                                          Class I Area - Salt Creek NWRW, NM
        •WBDust      • Road Dust      | On-Road Mobile  O WRAP Area Q&3   Biogenic    • Arrthro Fire
    
        D Fugitive Dust     Off-Road Mobile  ~ Off-Shore      []Area            Natural Fire  | Point
    
                                                                         Source: From the TSS website (see Table 9-1).
    
    Figure 9-43.   Results of the weighted emissions potential tool applied to primary OC emissions
                  (top) and EC emissions (bottom) for the baseline and projected 2018 emissions
                  inventories for Salt Creek W. Only source regions (WRAP states and other
                  regions) with the largest estimated contributions are shown (i.e., Arizona,
                  California, CenRAP, Colorado, eastern U.S.,  Idaho, Mexico, Montana, New Mexico,
                  Nevada, Oregon, Utah, and Wyoming from left to right). The scale is normalized
                  (i.e., unitless) one over distance weighted emissions multiplied by trajectory
                  residence time.
    December 2009
    9-56
    

    -------
          For the most easterly of the selected WRAP sites, Badlands NP and Salt Creek, the weighted
    emissions potential results for primary OC and EC (Figure 9-42 and Figure 9-43) show potential
    contributions from a greater number of states and multi-state regions than for selected sites further to
    the west. This may be due in part to trajectories associated with worst haze conditions for these two
    sites being moderately long (-500 km) and in multiple directions. Natural fire emissions have the
    greatest potential to contribute to organic species PM at Badlands NP, but are less likely to be
    dominant at Salt Creek or at either site in its contribution to EC PM concentrations. The
    contributions by emissions from area and mobile sources from the home states and states to the east
    (Central States Regional Air Partnership states are labeled "CEN" in the figures) are potentially
    greater than by natural fire; this is especially true for contributions to EC PM.
          WRAP applied the weighted emissions potential tool to assess likely source types and regions
    contributing to coarse mass concentrations. The results for the  six selected monitoring sites (not
    shown) are as follows. Most dust at Olympic NP is likely to be from fugitive dust sources in
    Washington state, while at San Gorgonio it is likely more from road dust with smaller amounts from
    fugitive dust sources. The amount from wind-blown dust is small for both of these far westerly sites.
    Wind-blown dust is likely the largest source contributing to coarse mass at Grand Canyon NP,
    Badlands NP and Salt Creek W with most of it originating in the home-state for those sites. The
    weighted emissions potential results for coarse mass at Yellowstone are different from those of the
    other five selected sites in that Idaho and Montana each have a higher potential to contribute to
    coarse mass on the worst haze days than the home state (Wyoming), and that wind-blown and road
    dust both contribute substantially as does fugitive dust and natural fire.
          In another WRAP-sponsored effort to better understand the causes of remote area haze in the
    western U.S., each of the worst haze days for all western IMPROVE monitoring sites where dust
    (defined as the sum of coarse  mass and fine soil PM) was the largest contributor to light extinction
    was  separately assessed to categorize the most likely dust source (Kavouras et al., 2007, 156630;
    Kavouras et al., 2009, 191976) and the Causes of Haze Website - see Table 9-1). Elemental
    composition was used to assess the likelihood that the dust was associated with long-range transport
    from Asia. A regression analysis at each site between dust concentrations and coincident local wind
    speed was used to generate site-specific estimates of local windblown dust for each sample period.
    Finally, back trajectory analysis combined with maps constructed of wind erosion potential
    (i.e., developed by combining soil types and land cover classifications)  are used in a manner similar
    to the weighted emissions potential analysis to identify the likelihood of regionally transported
    wind-blown dust as the source. These assessments were conducted on each of the 610 so-called
    "worst dust haze days" at 70 monitoring sites for data from 2001-2003 to classify each day by its
    likely contributions from Asian dust, local windblown dust, upwind transport and undetermined. The
    undetermined category includes those sample periods that failed to be classified into one  of the other
    three source categories suggesting that mechanically suspended dust activities (e.g., unpaved road
    dust, agricultural, construction and mining activities) may be responsible.
          Of the 610 "worst dust haze days" at the 70 WRAP monitoring sites, 55 sample periods are
    classified as Asian dust influenced, almost exclusively in the spring; 201 sample period are classified
    as local windblown dust, mostly in the spring but some in all seasons; 240 sample periods are
    classified as upwind transported dust, with a broader seasonal distribution centered on summer and
    few instances during winter; and  114 are in the undetermined category with most in summer and
    least in winter. Most dust days occurred in the deserts  of Arizona, New  Mexico, Colorado, western
    Texas and southern California, and these were dominated by local and regionally transported
    wind-blown dust (e.g., 84% for Salt Creek W). Asian dust caused only a few of the worst dust days
    during the 3-year assessment period, though it is an important source (i.e., 10-40% of the worst dust
    days) for sites in the more northern regions of the West with greater vegetative land-cover where
    local and regionally transported wind-blown dust was infrequent. The frequency of worst dust events
    classified as undetermined was greatest for sites in the vicinity of large  urban and agricultural areas
    such as those in California and southern Arizona.
    December 2009                                  9-57
    

    -------
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    Sulfate Haze Source Attribution
    
    • Carbon      • Other Mexico
    
    • Texas       • Eastern US
    
    D Western US  D Other
                  Organics + LAC + Nitrates +
    
                      Fine Soil + Coarse
            July 9
                     August 9
    September 9
    October 9
                                      Source: Reprinted with Permission of the Air & Waste Management Associaiton from Pitchford et al. (2005,156874)
    Figure 9-44.   BRAVO study haze contributions for Big Bend NP, TX during a 4-mo period in
                   1999. Shown are impacts by various particulate SO/' sources, as well as the
                   total light extinction (black line) and Rayleigh or clear air light scattering.
    December 2009
                                       9-58
    

    -------
     2004 Annual
     ammNOSf
    Figure 9-45.   Maps of spatial patterns for average annual particulate nitrate measurements
                 (top), and for ammonia emissions for April 2002 from the WRAP emissions
                 inventory (bottom).
    December 2009
    9-59
    

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                            NO
    
                 WRAP 36k base02a All Sources Emissions
                        2002 Yearly Total
       1.250
       0.000
     LOG(tons/yea»)
                      December 31,2002 0:00:00
                Min= 0.000 at (4,1), Max= -1.995 at (130,68)
                             NO2
    
                  WRAP 36k base02aAII Sources Emissions
                          2002 Yearly Total
        0.000  1
      LOG(tons/yeal)
       PAUE
       bv
       WCNC
         December31,2002 0:00:00
    Min= 0.000 at (4,1 ),Max= 4.041 at (130,68)
    Figure 9-46.    Maps of spatial patterns of annual NO (left) and N02 (right) emissions for 2002
                   from the WRAP emissions inventory.
    
          Source attribution of the participate SO42~ contribution to haze at Big Bend NP, TX was a
    primary motivation for the BRAVO study.  Schichtel et al. (2005, 156957) showed that during the
    four-month field monitoring study (July-October 1999), SO2 emissions sources in the U.S. and
    Mexico were responsible for -55% and -38% of the particulate SO42~, respectively. Among U.S.
    source regions, Texas was responsible for -16%, eastern U.S.  -30%, and the western U.S. -9%. A
    large coal fired power plant, the Carbon facility in Mexico, just south of Eagle Pass, TX, was
    responsible for -19%, making it the largest single contributor. Pitchford et al. (2005, 156874) put
    these results into the context of other component contributions to regional haze, plus seasonal and
    longer-term variations in haze by particulate components. Figure 9-44 shows the temporal variation
    of the contributions by the various SO2 emissions source regions plus the Carbon facility during the
    BRAVO study period. The largest particulate SO42~ peak haze periods are dominated by infrequent
    large contribution by emission sources in TX and the eastern U.S., while Mexican sources including
    the Carbon facility are more frequent contributors to haze, but at generally lower light extinction
    values. Particulate nitrate contributions to haze at Big Bend NP are among the lowest measured in
    the U.S. (-3% of light extinction on average and for worst haze episodes).
          Nitrate concentrations are a significant contributor to light extinction further to the north of
    Texas in the center of the country. While SO42~ can be in particulate form though not fully
    neutralized by ammonia, nitric acid from NOX emissions requires neutralization by  ammonium to
    become particulate ammonium nitrate. One way to explore the causes of the Midwest nitrate bulge is
    to compare its spatial distribution with the spatial distributions of NOX and ammonia emissions.
    Figure 9-45 shows a map of the annual average particulate nitrate concentrations (top) with a map of
    ammonia emissions directly below it. Animal agriculture is  responsible for most of the ammonia
    emissions in the Midwest. The striking similarity between the ambient particulate nitrate
    concentration and the ammonia emissions spatial patterns with regional maximum centered on Iowa
    is in contrast to the NOX (i.e., NO + NO2) emissions spatial patterns, shown in Figure 9-46. NOX
    emissions are high over a broad region of the country associated with the larger population densities
    and greater numbers of fossil fuel electric generation plant generally to the east of the Midwest
    nitrate bulge. While both ammonia and nitric acid are needed to form particulate ammonium nitrate,
    the maps suggest the Midwest nitrate bulge is due primarily to the abundance of free ammonia (i.e.,
    the amount beyond what is required to neutralize the acidic particulate SO42~). By contrast, the
    region to the  east of the Midwest nitrate bulge should have plenty of nitric acid given the higher
    emissions of NOX, but apparently has  a deficiency of free ammonia. The few eastern monitoring
    sites with locally high particulate nitrate (near southeastern PA) are located within a small region of
    high density animal agriculture that shows up as a high ammonia emissions region in Figure 9-45.
    Note that California's South Coast and Central Valley have both high ammonia and high NOX
    emissions, explaining the high particulate nitrate contribution  to haze there.
    December 2009
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          To better understand the role of ammonia in the formation of the Midwest nitrate bulge, the
    Midwest RPO and Central States Regional Air Partnership deployed a measurement program from
    late 2003 through early 2005 at 10 locations (9 rural and 1 urban) in the region (see Figure 9-47) to
    monitor particulate SO42~, nitrate, and ammonium ions, plus the precursor gases  sulfur dioxide, nitric
    acid, and ammonia (Kenski et al, 2004, 192078; Sweet et al., 2005, 180038). These data have been
    used as input for thermodynamic equilibrium modeling to assess the changes in PM concentrations
    that would result from changes to precursor concentrations (Blanchard and Tanenbaum, 2006,
    190005; Blanchard et al., 2007, 098659). Blanchard and Tanenbaum (2006, 190005) and Blanchard
    et al. (2007, 098659) conclude that the current conditions at nine of the ten sites  are near the point of
    transition between the precursor species (nitric acid and ammonia) that limits the formation of
    particulate nitrate. If excess ammonia increases, either by greater ammonia emissions or by
    anticipated decreases in SO2 emissions, then nitric acid concentration would need to be reduced (via
    lower NOX emissions) in order to reduce the particulate nitrate concentration.
          Given the comparability of particulate SO42~ and nitrate with regard to their light extinction
    efficiencies, their visibility impacts are proportional to the sum of their mass concentrations. A
    reduction in SO42~ caused by SO2 emission reductions would reduce the particulate SO42~
    concentration, though according to the thermodynamic equilibrium modeling for these sites the
    particulate nitrate concentration will be increased somewhat. However, the total  particulate SO42~
    plus nitrate concentration would be reduced so visibility impacts would be decreased. At current
    ammonium concentrations the predicted response of changes to SO42~ and nitric  acid concentrations
    (i.e., SO2 and NOX emissions changes) are similar in respect to the resulting magnitude of changes to
    the total particulate SO42~ plus nitrate concentrations. At all but two sites the total particulate SO42~
    plus nitrate concentrations would decrease if either ammonia or nitric acid where reduced.
                                                                             Source: Kenski et al. (2004,1920781
    Figure 9-47.   Midwest ammonia monitoring network.
          A further degree of complications in understanding the response of particulate nitrate to
    changes in precursor concentrations results from the temperature and humidity dependence of the
    partition between particulate ammonium nitrate and the disassociated gaseous nitric acid and
    ammonia. This dependence causes seasonal and even diurnal differences in the expected responses
    of particulate nitrate concentrations to changes in precursor concentrations. As expected, during the
    colder times of the year the total particulate concentrations are more sensitive to changes in ammonia
    and nitric acid concentrations than during the warmer seasons when SO42~ concentrations are greater.
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          As shown in Figure 9-48, results of an air transport assessment to identify emission source
    areas associated with high particulate nitrate at five monitoring locations in the East (four
    remote-area sites and Toronto, Canada) implicate the high ammonia emissions region of the Midwest
    as a common source region (Canada-US Air Quality Committee, 2004, 190519). This assessment
    does not preclude local sources of the precursor gases responsible for parti culate ammonium nitrate,
    but does suggest that long-range transport of parti culate nitrate or ammonia from the high emissions
    region of the Midwest is also contributing to eastern nitrate episodes.
                         Upwind Probability Fields for Ammonium Nitrate
                        Lye Brook VT,
    real Smoky Mountains NP
                                                                    Source: Canada-U.S. Air Committee (2004,190519).
    
    Figure 9-48.   Upwind transport probability fields associated with high participate nitrate
                  concentrations measured at Toronto, Canada; Boundary Water Canoe Area, MN;
                  Shenandoah NP, VA; Lye Brook, VT; and Great Smoky Mountains NP, TN.
    
          In a similar air transport assessment for measurements at Underbill, VT and at Brigantine, NJ,
    Hopke et al. (2005, 156567) identified separate regions associated with particulate SO42~
    accompanied by trace particulate components associated with coal burning (e.g., Se) and
    accompanied by trace particulate components associated with oil burning (e.g., V). As shown in
    Figure 9-49, the coal-burning related particulate SO42~ for these two monitoring sites is associated
    with long-range transport from the Ohio River Valley, while oil-burning related particulate SO42~ is
    from more nearby emissions in the high population region of coastal New York, New Jersey,
    Massachusetts, and Connecticut.
    December 2009
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                                      Source: Reprinted with Permission of Environmental Science and Technology from Hopke, et al. (2005,156567).
    
    Figure 9-49.   Trajectory probability fields for periods with high participate SQ*~ measured at
                  Underbill, VT and Brigantine, NJ (shown as white stars) associated with
                  oil-burning trace components (left) and with coal-burning trace components
                  (right). Shown for comparison are the interpolated 862 emissions areal density
                  contours for oil combustion sources (emissions times 10) and coal combustion
                  sources, displayed as yellow and red contour lines, respectively.
    
          The Regional Aerosol Intensive Network (RAIN) was established by MANE-VU to generate
    enhanced continuous visibility, plus fine particle mass and composition monitoring data at a string of
    three monitoring locations along the transport path from the Ohio River Valley to coastal Maine
    (NESCAUM, 2006, 156802). The dominant role of particulate SO42~ in the northeast is well
    demonstrated by a scatter plot of RAIN data that shows the relationship between particulate SO42~
    extinction, calculated using the IMPROVE algorithm plotted against directly measured particle light
    scattering for hourly data over a 8-mo period, beginning in July 2004 at the Acadia NP, ME
    monitoring site (see Figure 9-50). Particulate SO42~ explains 90% of the variance in particulate light
    scattering even though it is responsible for only about 64% of the total light extinction (annual
    averaged value from the VIEWS web site). Adding the contribution by the second-largest regional
    contributor to light extinction, particulate  OC with about 14%, does not improve the variance
    explained, but does  increase the slope to 0.78. The noticeable difference between these two plots is
    that the particulate SO42~ alone underestimates light scattering during low haze periods (points on the
    plot are below the regression line for light scattering <70 Mm"1), while the agreement is improved
    with the addition of particulate OC contributions to haze (regression slope is nearer to one and
    reduced bias for low haze periods). This implies that particulate SO42~ and any other co-varying PM
    species are largely responsible for the highly  impacted periods, while OC and other co-varying PM
    species contribute more  during the less extreme haze periods. Particulate nitrate contribution to light
    extinction at Acadia is about 10% on average.
    December 2009
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          Nephelometer Bsp versus SULFATE Bsp
                                                       Nephelometer Bsp vs  {SULFATE + OMC)
                   50   100   150   200   250   300   3:
                                                                50    100    150   280   250   300    3!
                 2-Hour Nephelometer Bsp (1/Mmeters)
    Figure 9-50.
                                                2-
                                                                 2-Hr Nephelometer (1,'Mmeters)
    
                                                         Source: RAIN Preliminary Data Analysis Report (NESCAUM, 2006,156802'
                                                                         2-
    Scatter plots of participate SO/' (left) and participate S04Z" and organic mass
    (right) versus nephelometer measured particle light scattering for Acadia NP, ME.
          Particulate nitrate concentrations are considerably lower in the SO42 -dominated warmer
    southeastern U.S. than in the Northeast and upper Midwest. Blanchard et al. (2007, 098659)
    conducted thermodynamic equilibrium modeling on data from the eight SEARCH monitoring sites
    and found that total particulate nitrate plus SO42~ is much more responsive to changes in SO2
    concentrations than to changes in nitric acid concentrations, which in turn is more responsive than
    changes in ammonia concentrations.
          The VISTAS RPO commissioned an emissions sensitivity study using CMAQ modeling on
    winter and summer 2009 emissions projected from the 2002 emissions inventory (NCDENR, 2007,
    156798). Figure 9-51 contains bar plots for two North Carolina Class I areas that indicate projected
    changes in light extinction for the worst haze day due to 30% emissions reductions by particulate
    species, source types and location across the Southeastern states modeling domain (i.e., as far west
    as Texas, as far north as Pennsylvania, as far south as the Florida Keys, and as far east as -300 km
    from the North Carolina coast). Great Smoky Mountains in the southern Appalachian Mountains has
    the greatest sensitivity to changes by SO2 emissions from electrical generation units (EGU) and to a
    lesser extent other SO2 emission sources in the region. Reductions of NOX emissions from ground or
    point sources are not nearly as effective as SO2 reductions in reducing the light extinction at Great
    Smoky Mountains. This is due principally to the worst days at Great Smoky Mountains occurring
    during the summer, when temperatures are too high to support high particulate nitrate
    concentrations. For the same reason, ammonia emission reductions are also ineffective. Swanquarter
    W, NC is a coastal location where some of the worst haze days are during the winter and include
    contributions from particulate ammonium nitrate. Both SO2 and ammonia emissions reductions
    would be effective at reducing worst haze days at the Swanquarter W, though NOX emissions are not
    as effective presumably because the atmosphere is ammonia-limited for particulate nitrate
    production.
    December 2009
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                       Great Smoky Mtns, TN (20% Worst Days)
                           • Bio VOC.
                           D Anthro VOC
                           • BCs
                           D MRPO
                           • M-VU
                           DCEN
                           • VISTAS
                           • wv
                           n VA
                           DTN
                           DSC
                           • NC
                           • MS
                           DKY
                           DGA
                           • FL
                           DAL
                      Swanquarter, NC (20% Worst Days)
                           • Bio VOC
                           D Anthro VOC
                           • BCs
                           • MRPO
                           • M-VU
                           DCEN
                           • VISTAS
                           • WV
                           DVA
                           DTN
                           DSC
                           • NC
                           • MS
                           DKY
                           DGA
                           • FL
                           DAL
                                                                           Source: NCDENR (2007, 156798).
    Figure 9-51.    CMAQ air quality modeling projections of visibility responses on the 20% worst
                  haze days at Great Smoky Mountains NP, NC (top) and Swanquarter W, NC
                  (bottom) to 30% reductions. This is from a projected 2009 emission inventory of
                  visibility-reducing pollutants by source category and geographic areas.
    9.2.4.  Urban Visibility Valuation and Preference
          The Clean Air Act §302(h) defines public welfare to include the effects of air pollution on
    "... visibility, ...  and personal comfort and wellbeing." Though good visibility conditions in Class I
    (e.g., NPs) and wilderness areas have long been recognized as important to the public welfare (see
    discussions in EPA (2004, 056905; 2005, 090209) and Chestnut and Dennis (1997, 014525).
    visibility conditions in urban areas also contribute to the public welfare. Although visibility
    impairment may be caused by either natural or manmade conditions (or both), it is only impairment
    that occurs as a result of air pollution (either alone or in combination with water vapor or other
    atmospheric conditions) that can be mitigated by regulations such as the RHR (40 CFR 51.300
    through 309) or the Secondary NAAQS. The term visual air quality (VAQ) is used here to refer to
    December 2009
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    the visibility effects caused solely by air quality conditions, so for example it excludes the reduced
    visibility caused by fog. Visibly poor air quality causes people to be concerned about substantive
    health risks, but degraded VAQ adversely affects people in additional ways. These include the
    aesthetic and wellbeing benefits of better visibility, improved road and air safety, and enhanced
    recreation in activities like hiking and bicycling. Because the human health impacts of air pollution
    are assessed under the Primary NAAQS, it is necessary to separate out these non-health components
    associated with the visibility condition produced by a given amount of air pollution when assessing
    the need for additional  regulation to protect the public welfare effect of visibility under the
    Secondary NAAQS. The degree to which previous human preference and valuation studies for VAQ
    have adequately made this distinction and separation is an important issue in applying results from
    available studies in a Secondary NAAQS (or benefits estimation for any policy affecting VAQ)
    context. The remainder of this discussion is focused on those aesthetic and wellbeing qualities
    associated with a given VAQ in urban areas.
          The term "urban visibility" is  used to refer to VAQ throughout a city or metropolitan area.
    Urban visibility includes the VAQ conditions in all locations that people experience in their daily
    lives, including scenes  such as residential streets and neighborhood parks, commercial and industrial
    areas, highway and commuting corridors, central downtown areas, and views from elevated locations
    providing a broad overlook of the metropolitan area. Thus urban visibility includes VAQ conditions
    in major cities and smaller towns and encompasses all the VAQ an individual resident sees on a
    regular basis. Visibility conditions in urban and suburban locations are therefore distinct from
    visibility in rural or wilderness settings such as the Class 1 areas defined by the Clean Air Act, which
    include NPs and similar natural settings.
          Visibility has direct significance to people's enjoyment of daily activities and their overall
    wellbeing. Visibility conditions can  be described both as an aesthetic quality as well as  a
    scientifically measurable set of atmospheric conditions. Due to the subjective nature of aesthetics,
    people's preferences with respect to visibility are difficult to express or quantify, but people have
    expressed in many different ways that they enjoy and value a clear view. A number of social  science
    studies have been undertaken to link perceived urban visibility to an array of effects reflecting the
    overall desire for good VAQ, and the benefits of improving currently degraded VAQ. This wide
    range of diverse studies have identified types of benefits of good VAQ.
          For example, psychological research has demonstrated that people are emotionally  affected by
    low VAQ such that their overall sense of wellbeing is diminished (e.g., Bickerstaff and Walker,
    2001, 156271). Researchers have also shown that perception of pollution is correlated with stress,
    annoyance, and symptoms of depression (Evans  and Jacobs,  1982, 179899; Jacobs et al, 1984,
    156596; Mace et al., 2004,  180255). Sociological research has demonstrated that VAQ is  deeply
    intertwined with a "sense of place,"  effecting people's sense of the desirability of a neighborhood
    quite apart from the actual physical  conditions of the area (e.g., ABT, 2002, 156186; Day, 2007,
    156386; Elliot et al., 1999,  010716;  Howel et al., 2002, 156571). Public policy research finds that
    people think it is important to protect visibility, and accept the concept of setting standards to protect
    visibility (e.g., ABT, 2001,  156185;  BBC Research & Consulting, 2002, 156258; Ely et al., 1991,
    156417; Pry or, 1996, 056598). Finally,  economic valuation research has measured the amount of
    money that people are willing to pay to protect or improve both urban visibility (e.g., summary
    review in Beron et al., 2001, 156270; Chestnut and Dennis, 1997, 014525) and natural locations
    such as NPs and other locations defined by the Clean Air Act as  Class I visibility area (e.g., summary
    review in Chestnut and Dennis, 1997, 014525).
          Urban visibility has been examined in two types of studies directly relevant to the NAAQS
    review process: urban visibility preference studies and urban visibility  valuation studies. The
    purpose of the remainder of this section is to review preference studies in four urban areas, as well as
    one new urban visibility valuation study not previously discussed in previous EPA Criteria
    Documents or OAQPS Staff Papers.
          Both types of studies are designed to  evaluate individuals' desire (or demand) for good VAQ
    where they live, using different metrics to evaluate demand. Urban visibility preference studies
    examine individuals' demand by investigating what amount of visibility degradation is unacceptable
    while economic studies examine demand by investigating how much one would be willing to pay to
    improve visibility.
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    9.2.4.1.   Urban Visibility Preference Studies
    
          One group of urban visibility research projects focused on identifying preferences for urban
    VAQ without necessarily estimating the economic value of improving visibility. This group of
    preference studies used a common focus group method to estimate the visibility impairment
    conditions that respondents described as "acceptable." The specific definition of acceptable was
    largely left to each individual respondent, allowing each to identify their own preferences.
          There are three completed studies that used this method, and two pilot studies that provided
    additional information (Table 9-2). The completed studies were conducted in Denver, Colorado (Ely
    et al, 1991,  156417). two cities in British Columbia, Canada (Pryor, 1996, 056598). and Phoenix,
    Arizona (BBC Research & Consulting, 2002, 156258).  The additional studies were conducted in
    Washington, DC (ABT, 2001, 156185; Smith and Howell, 2009, 198803).
          Each study collected information in a focus group setting, presenting slides depicting various
    visibility conditions. All four studies used photographs  of a single scene from the  study's city; each
    photo included images of the broad downtown area and spreading out to the hills or mountains
    composing the scene's backdrop. The maximum sight distance under good conditions varied by city,
    ranging from 8 km in Washington, DC to mountains hundreds of kilometers away in Denver.
    Multiple  photos of the same scene were used to present approximately 20 different visibility
    impairment conditions. The Denver and British Columbia studies used actual photographs taken in
    the same location to depict various visibility conditions. The  Phoenix and Washington, DC studies
    used photographs prepared using the WinHaze software from Air Resource Specialists (ARS).
    WinHaze is a computer-imaging software program that simulates visual air quality differences of
    various scenes, allowing the user to "degrade" an original near-pristine visibility condition
    photograph to create a photograph of each desired VAQ condition.
          A common characteristic of the three visibility preference studies was that each was conducted
    in the West where distant mountains were shown in the photograph used to elicit local participant
    responses about visibility. Among other issues, the Washington D.C. pilot study was the first step in
    a process to  expand the results  to other regions where typical scenes may have different sensitivity to
    perceived visibility changes in  PM air quality and where participants may have different acceptable
    visibility preference values.
          The range of median preference values for an acceptable amount of visibility degradation from
    the 4 urban areas was approximately 19-33 dv. Measured in terms of visual range (VR), these
    median acceptable values were between approximately 59 and 20 km.
    Table 9-2.    Summary of urban visibility preference studies.
    
    Report Date
    Duration of
    session
    Compensation
    # focus group
    sessions
    # participants
    Age range
    Annual or
    seasonal
    # total scenes
    presented
    # of total visibility
    conditions
    presented
    Denver, CO
    1991
    
    None (civic groups)
    17
    214
    Adults
    Wintertime
    Single scene of
    downtown with
    mountains in
    background
    20 conditions (+ 5
    duplicates)
    Phoenix, AZ
    2003
    45min
    $50
    27 total at 6 locations,
    Including 3 in Spanish
    385
    18-65+
    Annual
    Single scene of
    downtown and
    mountains, 42 km
    maximum distance
    21 conditions (+ 4
    duplicates)
    2 British Columbia cities
    1996
    50 min
    None (class room exercise)
    4
    180
    University students
    Summertime
    Single scene from each city
    20 conditions (10 each from each city)
    Washington, DC
    (2001)
    2001
    2h
    $50
    1
    9
    27-58
    Annual
    Single scene of DC Mall
    and downtown, 8 km
    maximum sight
    20 conditions (+ 5
    duplicates)
    Washington, DC
    (2009)
    2009
    
    None
    3 tests
    64
    Adults
    Annual
    Single scene of DC
    Mall and downtown, 8
    km maximum sight
    22 conditions
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    Source of slides
    Medium of
    presentation
    Ranking scale
    used
    Visibility range
    presented
    Health issue
    directions
    Key questions
    asked
    
    
    
    Mean dv found
    "acceptable"
    Denver, CO
    Actual photos taken
    between 9am and
    3pm
    Slide projection
    7 point scale
    11 to 40 dv
    Ignore potential
    health impacts;
    visibility only
    a)RankVAQ(1-7
    scale)
    b) Is each slide
    "acceptable"
    c) "How much haze
    is too much?"
    
    20.3dv
    Phoenix, AZ
    WinHaze
    Slide projection
    7 point scale
    15 to 35 dv
    Judge solely on
    visibility, do not
    consider health
    a)RankVAQ(1-7
    scale)
    b) Is each slide
    "acceptable"
    c) How many days a
    year would this picture
    be "acceptable"
    
    23-25 dv
    2 British Columbia cities
    Actual photos taken at 1 p.m. or 4 p.m.
    Slide projection
    7 point scale
    13-25 dv (Chilliwack) 13.5-31. 5 dv
    (Abbotsford)
    Judge solely on visibility, do not
    consider health
    a) Rank VAQ (1-7 scale)
    b) Is each slide "acceptable"
    
    
    -23 dv(Chilliwack),
    ~19dv(Abbotsford)
    Washington, DC
    (2001)
    WinHaze
    Slide projection
    7 point scale
    9-38 dv
    Health never
    mentioned, "Focus only
    on visibility"
    a) Rank VAQ (1-7
    scale)
    b) Is each slide
    "acceptable"
    c) if this hazy, how
    many hs would it be
    acceptable (3 slides
    only)
    d) valuation question
    -20 dv (range 20-25)
    Washington, DC
    (2009)
    WinHaze
    Slide projection
    7 point scale
    9-45 dv
    Health never
    mentioned, "Focus only
    on visibility"
    a) Rank VAQ (1-7
    scale)
    b) Is each slide
    "acceptable"
    
    
    -30 dv
    9.2.4.2.   Denver, Colorado Urban Visibility Preference Study
    
          The Denver urban visibility preference study (Ely et al, 1991, 156417) was conducted on
    behalf of the Colorado Department of Public Health and Environment (CDPHE). The study
    conducted a series of focus group sessions with 17 civic and community groups in which a total of
    214 individuals were asked to rate slides. The slides depicted varying values of VAQ for a
    well-known Denver vista, including a broad view of downtown Denver with the mountains to the
    west composing the scene's background. The participants were instructed to base their judgments on
    three factors:
    
        1.  The standard was for an urban area, not a pristine NP area where the standards might be
           more strict;
        2.  The value of an urban visibility standard violation should be set at a VAQ  value considered
           to be unreasonable, objectionable, and unacceptable visually; and
        3.  Judgments of standards violations should be based on visibility only, not on health effects.
    
          Participants were shown 25 randomly ordered slides of actual photographs.  The visibility
    conditions presented in the slides ranged from 11-40 dv, approximating the 10th-90th percentile of
    wintertime visibility conditions in Denver. The participants rated the 25 slides based on a scale of
    1 (poor) to 7 (excellent), with 5 duplicates included. They were then asked to judge whether the slide
    would violate what they would consider to be an appropriate urban visibility standard (i.e., whether
    the amount of impairment was "acceptable" or "unacceptable"). The individual's judgment of a
    slide's VAQ and whether the slide violated a visibility standard were highly correlated (Pearson
    correlation coefficient >80%), as were the VAQ ratings and the yes/no "acceptable" response. The
    participant's median response was that a visibility condition of 20.3 dv (extinction coefficient
    bext= 76Mm"1, or VR ~51 km) was judged as "acceptable." The CDPHE subsequently established a
    Denver visibility standard at this value (defined as bext = 76Mm"1), based on the median 50%
    acceptability findings from the study.
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    9.2.4.3.   Phoenix, Arizona Urban Visibility Preference Study
    
          The Phoenix urban visibility preference study (BBC Research & Consulting, 2002, 156258)
    was conducted on behalf of the Arizona Department of Environmental Quality. The Phoenix study
    patterned its focus group survey process after the Denver study. The study included 385 participants
    in 27 separate focus group sessions. Participants were recruited using random digit dialing to obtain
    a sample group designed to be demographically representative of the larger Phoenix population.
    Focus group sessions were held at six neighborhood locations throughout the metropolitan area to
    improve the participation rate. Three sessions were held in Spanish in one region of the city with a
    large Hispanic population (25%), although the final overall participation of native Spanish speakers
    (18%) in the study was modestly below the targeted value. Participants received $50 as an
    inducement to participate.
          Participants were shown a series of 25 images of the same vista of downtown Phoenix, with
    South Mountain in the background at a distance of about 40 km. Photographic slides of the images
    were developed using WinHaze. The visibility impairment conditions ranged from 15-35 dv (the
    extinction coefficient, bext, range was approximately 45 Mm"1 to 330 Mm" , or a visual range of
    87-12 km). Participants first individually rated the randomly shown slides on a VAQ scale of
    1 (unacceptable) to 7 (excellent). Participants were instructed to rate the photographs solely on
    visibility, and to not base their decisions on either health concerns or what it would cost to have
    better visibility. Next, the participants individually  rated the randomly ordered slides as "acceptable"
    or "unacceptable," defined as whether the visibility in the slide is unreasonable or objectionable.
    Better visibility conditions (15 dv and 20 dv) were judged "acceptable" by 90% of all participants.
    At 24 dv nearly half of all participants thought the VAQ was "unacceptable," with almost
    three-quarters judging 26 dv as unacceptable.
          The Phoenix urban visibility study formed the basis of the decision of the Phoenix Visibility
    Index Oversight Committee for a visibility index for the Phoenix Metropolitan Area (Arizona DEQ,
    2000, 019164). The Phoenix Visibility Index establishes an indexed system with 5 categories of
    visibility conditions, ranging from "Excellent" (14  dv or less) to "Very Poor" (29 dv or greater). The
    "Good" range is 15-20 dv. The environmental goal of the Phoenix urban visibility program is to
    achieve continued progress through 2018 by moving the number of days in lower quality categories
    into better quality categories.
    
    
    9.2.4.4.   British Columbia, Canada Urban Visibility Preference Study
    
          The British Columbia urban visibility preference study (Pryor, 1996, 056598) was conducted
    on behalf of the Ministry of Environment. The study conducted focus group sessions that were also
    developed following the methods used in the Denver study. Participants were students at the
    University of British Columbia, who participated in one of four focus group sessions with between 7
    and 95 participants.  A total of 180 respondents completed surveys (29 did not complete the survey).
          Participants in the study were shown slides of two suburban locations in British Columbia:
    Chilliwack and Abbotsford. Using the same general protocol as the Denver study, Pry or found that
    responses from this  study found the acceptable level of visibility was 23 dv in Chilliwack and 19 dv
    in Abbotsford. Pry or (1996, 056598) discusses some possible reasons for the variation in standard
    visibility judgments between the two locations. Factors discussed include the relative complexity of
    the scenes, potential bias of the sample population (only University students participated), and the
    different amounts of development at each location. Abbotsford (population 130,000) is an ethnically
    diverse suburb adjacent to the Vancouver Metro area, while Chilliwack (population 70,000) is an
    agricultural community 100 km east Vancouver in the Frazier Valley.
          The British Columbia urban visibility preference study is being considered by the B.C.
    Ministry of the Environment as a part of establishing urban and wilderness visibility goals in British
    Columbia.
    
    
    9.2.4.5.   Washington, DC Urban Visibility Preference Studies
    
          The Washington, DC urban visibility pilot study (ABT, 2001, 156185) was conducted on
    behalf of the EPA, and was designed to be a pilot focus group study, an initial developmental trial
    run of a larger study. The intent of the pilot study was to study both focus group method design and
    potential survey questions. Due to funding limitations, only a single focus group session was held,
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    consisting of one extended session with nine participants. No further urban visibility focus group
    sessions were held in Washington, DC.
          Due to the small number of participants, it is not possible to make statistical inferences about
    the opinions of the general population. The study does, however, provide additional useful
    information about urban visibility studies, potentially helping to both better understand previous
    studies as well as design future studies.
          The study also adopted the general Denver study method, modifying it as appropriate to be
    applicable in an eastern urban setting which has substantially different visibility conditions than any
    of the three western locations of the other preference studies. Washington's (and the entire East)
    visibility is typically substantially worse than western cities, and has different characteristics.
    Washington's visibility impairment is primarily a uniform whitish haze dominated by sulfates,
    relative humidity values are higher, the low lying terrain provides substantially shorter maximum
    sight distances, and many residents are not well informed that anthropogenic emissions impair
    visibility on hazy days.
          The Washington focus group session included questions on valuation,  as well as on
    preferences. The focus group was asked to state its preferences measured in an increase in the
    general cost of living for certain increments of improvement in visibility on atypical summer day. A
    general cost of living approach is one payment vehicle approach that can be used in willingness to
    pay studies, especially for environmental issues arising from multiple diverse emission sources (e.g.,
    transportation, electricity generation, industry, etc.) making a specific price increase potentially
    misleading.
          The first part of the focus group session was designed to be an hour long, and was comparable
    to the focus group sessions in the Denver and Phoenix studies. A single scene was used; a panoramic
    shot of the Potomac River, Washington mall and downtown Washington, DC. In the first part of the
    session people were asked to rate the VAQ of 25 photographs (prepared using WinHaze, and
    projected on a large screen), judge the acceptability of visibility condition in each slide, and answer
    the valuation questions. The second half of the session, however, was a moderated discussion session
    about the format and content of the first phase of the session. In this moderated discussion,
    participants were asked about their understanding of each question asked in the first half of the
    session. Particular issues in designing a focus group session were also explored. Important
    participant comments included:
    
        1.  Participants had been asked how they reacted to the initial direction to base their answers
           only on visibility, but health was never explicitly mentioned by the focus group moderator.
           Participants strongly agreed with the decision to not mention that health effects are
           associated with visibility impairment. They understood the directions as meaning they should
           ignore health issues, and said their answers would have been different if they included health
           as well as visibility in their judgments.
       2.  Differentiating between haze and weather conditions was difficult. Weather was not
           discussed in the focus group session, and the photographs were WinHaze altered photos with
           identical weather conditions. Participants mentioned they were still confused about the role
           of weather and humidity in the different visibility conditions presented in the photos.
       3.  Questions about how many hours an impairment level would be acceptable were confusing.
           Most participants were normally indoors during most of the day, so questions about duration
           of outdoor  conditions were difficult to answer.
       4.  Participants strongly agreed that not mentioning the purpose of the study, or the sponsor,
           until the very end (after  all the questions were answered) was viewed as very important.
           Most felt this information would have influenced their answers.
    
          The Smith and Howell (2009, 198803) study recreated the same WinHaze images used in the
    2001 Washington, DC urban visibility preference study, and followed a shortened version of the
    same question protocol as the 2001 study. The WinHaze images were presented to a total of
    64 participants who were all employees of CRA International, Inc. (Smith and Howell also are CRA
    International employees).
          The stated purpose of the  Smith and Howell (2009, 198803) study was to explore the
    robustness of the 2001 pilot study results. To investigate this issue, Smith and Howell (2009,
    198803)  conducted three different tests concerning urban visibility preferences. Each participant was
    involved with only one test. Test 1 was designed to replicate the 2001 study.  Test 2 reduced the
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    upper end of the range of VAQ by eliminating the 11 images used in Test 1 with a VAQ above
    27.1 dv. Test 3 increased the upper end of the range of VAQ by including two new images of worse
    VAQ; the two new images had a VAQ of 42 dv and 45 dv. Smith and Howell (2009, 198803)
    concluded that changing the range of VAQ presented to the participants affects the responses about
    whether a particular VAQ is acceptable.
    
    
    9.2.4.6.   Urban Visibility Valuation Studies
    
          The one recent urban visibility benefit assessment not included in earlier reviews is "The
    Benefits of Visibility Improvement: New Evidence from the Los Angeles Metropolitan Area" (Beron
    et al., 2001, 156270). Rather than a contingent valuation method (CVM) technique used in the
    majority of other urban visibility  valuation studies, Beron et al. (2001, 156270) used a housing
    market hedonic technique. The housing hedonic methods were used in previous urban visibility
    studies by Murdoch and Thayer (1988, 156788) and Trijonis et al. (1985, 078468). A housing market
    hedonic study views a housing unit as composed of a bundle of attributes, and uses housing sale
    price data from a large number of units in a metropolitan area to estimate the value of each
    component. Hedonic pricing has been used to  estimate economic values for environmental effects
    that have a direct effect on housing market values.  It relies on the measurement of differentials in
    property values under various environmental quality conditions including air pollution, visibility and
    other environmental amenities such as access to nearby beaches and parks, as well as by physical
    attributes of the house and attributes of the neighborhood.
          Beron et al. (2001, 156270) obtained data on approximately 840,000 owner-occupied, single
    family housing sales between 1980 and 1995 from the California South Coast Air Basin (composed
    of Los Angeles and Orange Counties, and the portions of Riverside and San Bernardino  Counties in
    the  greater metropolitan area). The real estate data  included information on the sale price of the
    house, 13 housing attributes (square footage, number of bathrooms, etc.), 9 neighborhood attributes
    (percent poverty, school quality, FBI crime index, etc.), and three air pollution variables:  ozone,
    particulates (measured by total suspended particulates, or TSP), and visibility.  Visibility  was
    measured as the annual average of visual range, measured in miles, and was obtained from seven
    airports within the study region. The visibility  range was from 12.4 miles (Los Angeles International
    Airport, 1991) to 31.9 miles (Palm Springs Airport, 1995). Ozone data (39 monitors) and TSP data
    (40 monitors) were obtained from the South Coast  Air Quality Management District. Annual mean
    values for each year were calculated for ozone and TSP.
          Beron et al. (2001, 156270) presented results for a hypothetical basin-wide 20% visibility
    improvement, or an increase from 15.3 to 18.4 miles, which is equivalent to approximately 27.6 dv
    to 25.8 dv. The initial results reflect the change in the purchase price of a house associated with this
    difference in VAQ, which can be interpreted as a present value of a stream of annual values over the
    lifetime of the house. The authors therefore selected a time horizon (30 yrs) and an interest rate (8%)
    to calculate an annual per household benefit per dv ranging from $484 to $1,756. The Beron results
    are  higher than the CVM-based values summarized in Chestnut and Dennis (1997, 014525). which
    ranged from $12 to $132 per dv. It should be noted that the $132 CVM values  cited  by Chestnut and
    Dennis (1997, 014525) is from a study in the Los Angeles area (Brookshire, 1979, 156298). The
    Beron et al. (2001, 156270) results are also higher than the Trijonis et al. (1990, 157058) hedonic
    study in the Los Angeles area, which had a range of $134 to $360 per dv per year. All values
    reported here are in terms of 1994 prices.
          A critical question for all urban visibility valuation studies is the extent to which the estimated
    values strictly reflect preferences for visibility, and do not include a component of preferences for
    reducing health risk from air pollution. The ability  to isolate the value of visibility from within the
    collection of intertwined benefits from visual air quality, which is inherently multi-attributed, is a
    challenge for all visibility valuation studies. Each study attempts to isolate visibility from other
    effect categories, but different studies take different approaches.
          Beron et al. (2001, 156270) include two measures of air pollution directly related to health
    effects in their housing market hedonic study,  ozone and particulates (using TSP as the metric for
    particulates), as well  as visibility. They argue that the presence of the two health-related  pollution
    conditions results  in an estimated hedonic demand  function for visibility that successfully separates
    the  health component of demand for overall air quality from the visibility component. An alternative
    interpretation is that the estimated visibility function still includes a component of health risk
    because the housing market data does not support completely isolating the demand for visibility (due
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    to correlated variables, omitted variables, measurement error, model specification error, etc.) from
    demand for health risk reductions measured by the two health related air quality metrics.
          A key issue in interpreting the Beron et al. (2001, 156270) results is whether the objective
    measures of air quality characteristics (e.g., visibility, PM concentrations, etc.) capture people's
    perceptions of the different aspects of air quality in a given location. To the extent the people
    simultaneously  use what they see regarding VAQ as an indicator of the overall air quality including
    potential health risks, then including all the measures  in the equation is not necessarily sufficient to
    isolate one effect from the other.
    
    
    9.2.5.  Summary of Effects on Visibility
    
          Visibility impairment is caused by light scattering and absorption by suspended particles and
    gases. NO2 is the only commonly occurring atmospheric pollutant gas that absorbs visible spectrum
    radiation, though in most situations the amount of light absorption by NO2 is overwhelmed by the
    higher amounts of particulate light extinction (i.e., the combination of scattering and absorption)
    usually accompanying high NO2 concentrations. Light scattering by gases in a pollutant-free
    atmosphere provides a limit to visibility in pristine conditions and is the largest contributor to the
    total light extinction during the least visibility-impaired periods in remote regions of the western
    U.S. There is strong and consistent evidence that PM  is the overwhelming source of visibility
    impairment in both urban and remote areas. EC and some crustal minerals are the only commonly
    occurring airborne particle components that absorb light. All particles  scatter light, and generally
    light scattering by particles is the largest of the four light extinction components. Although a larger
    particle scatters more light than a similarly shaped smaller particle of the  same composition, the light
    scattered per unit of mass is greatest for particles with diameters from approximately 0.3-1.0 um.
          For studies where detailed data on particle composition by size data are available, accurate
    calculations of light extinction can be made. However, routinely available PM  speciation data can be
    used to make reasonable estimates of light extinction  using relatively simple algorithms that multiply
    the  concentrations of each of the major PM species by its dry extinction efficiency and by a water
    growth term that accounts for particle size change as a function of relative humidity for hygroscopic
    species (e.g., SO42~, nitrate, and sea salt). This permits the visibility impairment associated with each
    of the major PM components to be separately approximated from PM  speciation monitoring data.
    There are six major PM components: PM2 5 SO4 ~ usually assumed to be ammonium sulfate, PM2 5
    nitrate usually assumed to be ammonium nitrate, PM2 5 OC, PM2 5 EC, PM2 5 crustal material
    (referred to as fine soil), and PMi0_2.s or coarse mass.
          Direct optical measurement of light extinction measured by transmissometer, or by combining
    the  PM light scattering measured by integrating nephelometers with the PM light absorption
    measured by an aethalometer offer a number of advantages compared  to algorithm estimates of light
    extinction based on PM composition and relative humidity data. The direct measurements are not
    subject to the uncertainties associated with assumed scattering and absorption efficiencies used in the
    PM algorithm approach. The direct measurements have higher time resolution  (i.e., minutes to
    hours), which is more commensurate with the visibility effects compared with  calculated light
    extinction using routinely available PM speciation data (i.e., 24-h duration).
          Particulate SO42~ and nitrate are produced in the atmosphere from gaseous precursors, making
    them secondary PM species. They both have comparable light extinction efficiencies (haze impacts
    per unit mass concentration) at any relative humidity value, their light scattering per unit mass
    concentration increases with increasing relative humidity, and at sufficiently high humidity values
    (RH>85%) they are the most efficient particulate species contributing  to haze.  Particulate SO42~ is
    the  dominant source of regional haze in the eastern U.S. (>50% of the particulate light extinction)
    and an important contributor to haze elsewhere in the country (>20% of particulate light extinction).
          Particulate nitrate is a minor component of remote-area regional haze in  the non-California
    western and eastern U.S., but an important contributor in much of California and in the upper
    Midwestern U.S. especially during winter when it is the dominant contributor to particulate light
    extinction. While both nitric acid (a reaction product of NOX  emissions) and ammonia are needed to
    form ammonium nitrate, the apparent reason for the Midwest nitrate bulge (i.e., region of high winter
    PM nitrate) is an abundance of atmospheric ammonia in this region principally from agricultural
    emissions. There is evidence that transport from the Midwest nitrate bulge region is responsible for
    some of the ammonium nitrate episodes experienced in downwind regions far to the east. Urban
    particulate nitrate concentrations are significantly elevated above  surrounding remote-area
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    background concentrations with the largest urban contributions in the western U.S. Particulate
    ammonium nitrate concentrations in California and the Midwestern nitrate bulge region are an order
    of magnitude greater than estimated natural ammonium nitrate concentrations. Thermodynamic and
    air quality simulation modeling show that particulate nitrate concentrations are sensitive to changes
    in either NOX emissions (from a combination of mobile and point sources) or ammonia emissions
    (principally from agricultural sources), with the responsiveness of particulate nitrate to emissions
    changes depending on the relative abundance of ammonia and nitric acid in the atmosphere.
          EC and OC have the highest dry extinction efficiencies of the major PM species and are
    responsible for a large fraction of the haze especially in the Northwestern U.S., though absolute
    concentrations are as high in the eastern U.S.  Both are a product of incomplete combustion of fuels,
    including those used in internal combustion processes  (gasoline and diesel emissions) and open
    biomass burning (smoke from wild and prescribed fire). OC PM species are also produced by
    atmospheric transformation of precursor gaseous emissions. Smoke plume impacts from large
    wildfires dominate many of the worst haze periods in the western U.S. Carbonaceous PM is
    generally the  largest component of urban excess PM2.5 (i.e., the difference between urban and
    regional background concentration). Western  urban areas have more than twice the average
    concentrations of carbonaceous PM than remote areas  sites in the same region. In eastern urban
    areas, PM25 is dominated by about equal concentrations of carbonaceous and SO42~ components,
    though the usually high relative humidity in the East causes the hydrated SO42~ particles to be
    responsible for about twice as much of the urban haze  as that caused by the carbonaceous PM.
          Radiocarbon dating of carbonaceous PM from twelve sites (eight in the West, two of which are
    urban) showed that about half of the urban area carbonaceous PM is from contemporary as opposed
    to fossil sources, while in remote areas the fraction that is contemporary ranges from 82-100%.
    Summer urban excess  carbonaceous PM is dominated  by fossil carbon for the two western urban
    areas (Phoenix, AZ and Seattle, WA), but nearly half of the winter urban excess for these two urban
    areas are from contemporary carbon sources (e.g., residential wood combustion). An empirical
    relationship between the radiocarbon analysis results and the more widely measured EC and OC data
    set was used to estimate the fraction of contemporary carbon at about 150 monitoring locations
    nationwide. The highest fraction of contemporary carbon is for the western remote areas sites during
    the summer (>90% contemporary) and the least was for eastern urban areas during the summer
    (<45% contemporary). Winter tended to have less extreme fractions of contemporary carbon for both
    remote and urban  areas. Alower bound estimate of 40% of the contemporary and 35% of the fossil
    carbon is from secondary conversion of gaseous precursor during the summer at the  twelve
    radiocarbon monitoring sites, suggesting that  primary carbonaceous PM whether from fossil or
    contemporary sources  represent less than two thirds  of the total carbonaceous PM.
          PM2.5 crustal material (referred to as fine soil) and coarse mass (i.e., PMi0 minus PM2.5) are
    significant contributors to haze for remote areas sites in the arid Southwestern U.S. where they
    contribute a quarter to a third of the haze, with coarse mass usually contributing twice that of fine
    soil.  Coarse mass  concentrations are as high in the Central Great Plains as in the Southwestern
    deserts though there are no corresponding high concentrations of fine soil as in the Southwest. Also,
    the relative contribution to haze by the high coarse mass in the Great Plains is much  smaller because
    of the generally higher haze values caused by the high concentrations of SO42~ and nitrate PM in that
    region.
          A comprehensive assessment of the 610 worst haze sample periods over a 3-yr period in the
    western U.S.  where dust is the major contributor categorized each site/sampler period into four
    causal groups: Asian dust, local windblown dust, transported regional windblown dust, and
    undetermined dust (i.e., not in one of the three other groups). Most dust days occurred at sites in
    Arizona, New Mexico, Colorado, western Texas, and southern California, and these  were dominated
    by local and regionally transported wind-blown dust. Asian dust caused only a few of the worst dust
    days during the 3-year assessment period, though it is an important source of dust  for the more
    northerly regions of the West (responsible for 10-40%  of their worst dust periods)  where there is
    rarely any windblown  dust probably due to the greater ground cover. The frequency  of worst dust
    events classified as undetermined was greatest for sites in the vicinity of large urban and agricultural
    areas such as  those in California and Southern Arizona.
          Visibility has  direct significance to people's enjoyment of daily activities and their overall
    sense of wellbeing. For example, psychological research has demonstrated that people are
    emotionally affected by poor VAQ such that their overall sense of wellbeing is diminished. Urban
    visibility has  been examined in two types of studies  directly relevant to the NAAQS  review process:
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    urban visibility preference studies and urban visibility valuation studies. Both types of studies are
    designed to evaluate individuals' desire for good VAQ where they live, using different metrics.
    Urban visibility preference studies examine individuals' preferences by investigating the amount of
    visibility degradation considered unacceptable, while economic studies examine the value an
    individual places on improving VAQ by eliciting how much the individual would be willing to pay
    for different amounts of VAQ improvement.
          There are three urban visibility  preference studies and two additional pilot studies that have
    been conducted to date that provide useful information on individuals' preferences for good VAQ in
    the urban setting. The completed studies were conducted in Denver, Colorado (Ely et al, 1991,
    156417). two cities in British Columbia, Canada (Pryor, 1996, 056598) and Phoenix, AZ
    (BBC Research & Consulting, 2002, 156258). The additional studies were conducted in Washington,
    DC (ABT, 2001, 156185: Smith and Howell, 2009, 198803). The range of median preference values
    for an acceptable amount of visibility  degradation from the 4 urban areas was approximately
    19-33 dv. Measured in terms of visual range (VR), these median acceptable values were between
    approximately 59 and 20 km.
          The economic importance of urban visibility has been examined by a number of studies
    designed to quantify the benefits (or willingness to pay) associated with potential improvements in
    urban visibility. Urban visibility valuation research prior to 1997 was summarized in Chestnut and
    Dennis (1997, 014525). and was also  described in the 2004 PM AQCD (U.S. EPA, 2004, 056905)
    and the 2005 PM Staff Paper (U.S. EPA, 2005, 090209). Since the mid-1990s, little new information
    has become  available regarding urban visibility valuation.
          Collectively, the evidence is sufficient to conclude that 3 C3USal relationship exists
    between PM and visibility impairment.
    
    
    
    9.3.  Effects on Climate
    
          While most of this ISA is restricted to consideration  of the emissions, transport and
    transformation, resulting concentrations, and effects from PM in the U.S., because the effects
    endpoint here is climate, a larger spatial domain is needed.  However, this assessment is not intended
    to be comprehensive even as a survey of the enormous range and volume of science related to
    climate effects from PM; rather, particular attention has been paid to data relevant to the U.S.
          The two principal sources for material in this section are  Chapter 2, "Changes in Atmospheric
    Constituents and in Radiative Forcing," (Forster et al., 2007, 092936) in the  comprehensive Working
    Group I report in the Fourth Assessment Report (AR4) from the Intergovernmental Panel on Climate
    Change (IPCC), Climate Change 2007: The Physical Science Basis (IPCC, 2007, 092765). hereafter
    IPCC AR4; and the U.S. Climate Change Science Program Synthesis and Assessment Product 2.3,
    "Atmospheric Aerosol Properties and  Climate Impacts," by Chin et al. (2009, 192130). hereafter
    CCSP SAP2.3. The EPA is a constituent agency member of the U.S. federated CCSP along with
    NOAA and NASA, which led production of CCSP SAP2.3 incorporating significant sections from
    EPA data and reports related particularly to U.S. emissions and measurements. Sections from each of
    these recent comprehensive reports are included here in their entirety or as emended as noted where
    they represent the most thorough summary of the climate effects of aerosols. (In the sections
    included from IPCC AR4 and CCSP SAP2.3, 'aerosols' is more frequently used than "PM" and that
    word is retained.)
    
    
    9.3.1.  The Climate Effects of Aerosols
    
          Section 9.3.1 comes directly from CCSP SAP2.3 Chapter 1 Section 1.2, with section,  table,
    and figure numbers changed to be internally consistent with this ISA.
    
                  Aerosols exert a variety of impacts on the environment. Aerosols (sometimes referred to
              particulate matter or "PM," especially in air quality applications), when concentrated near the
               surface, have long been recognized as affecting pulmonary function and other aspects of
              human health. Sulfate and nitrate aerosols play a role in acidifying the surface downwind of
              gaseous sulfur and odd nitrogen sources. Particles deposited far downwind might fertilize iron-
              poor waters in remote oceans, and Saharan dust reaching the Amazon Basin is thought to
              contribute nutrients to the rainforest soil.
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                    Aerosols also interact strongly with solar and terrestrial radiation in several ways. Figure
                9-52 offers a schematic overview. First, they scatter and absorb sunlight (Charlson and Pilat,
                1969, 190025; McCormick and Ludwig, 1967, 190528; Mitchell, 1971, 190546); these are
                described as "direct effects" on shortwave (solar) radiation. Second, aerosols act as sites at
                which water vapor can accumulate during cloud droplet formation, serving as cloud
                condensation nuclei or CCN. Any change in number concentration or hygroscopic properties
                of such particles has the potential to modify the physical and radiative properties of clouds,
                altering cloud brightness (Twomey, 1977,  190533) and the likelihood and intensity with which
                a cloud will precipitate (e.g.,Albrecht, 1989, 045783.; Gunn and Phillips, 1957, 190595; Liou
                and Ou, 1989,190407).
                    Collectively changes in cloud processes due to anthropogenic aerosols are referred to as
                aerosol indirect effects. Finally, absorption of solar radiation by particles is thought to
                contribute to a reduction in cloudiness, a phenomenon referred to as the semi-direct effect.
                This occurs because absorbing aerosol warms the atmosphere, which changes the atmospheric
                stability, and reduces surface flux.
                    The primary direct effect of aerosols is a brightening of the planet when viewed from
                space, as much of Earth's surface is dark ocean,  and most aerosols scatter more than 90% of
                the visible light reaching them. The primary indirect effects of aerosols on clouds include an
                increase in cloud brightness, change in precipitation and possibly an increase in lifetime; thus
                the overall net impact of aerosols is an enhancement of Earth's reflectance (shortwave albedo).
                This reduces the sunlight reaching Earth's surface, producing a net climatic cooling, as well as
                a redistribution of the radiant and latent heat energy deposited in the atmosphere. These effects
                can alter atmospheric circulation and the water cycle, including precipitation patterns, on a
                variety of length and time scales (e.g., Ramanathan et al, 2001, 042681; Zhang et al, 2006,
                190933).
                                                                                                     o
    • •; :•!•: : ^-^r:>
    Scattering & Unperturbed
    absorption of cloud
    radiation
    1 Direct effects j
    
    ^--^.-^
    Increased CDNC
    (constant LWC)
    (Twomey, 1974)
    I Cloud albedo effect/ 1
    I 1st indirect effect/ I
    \ Twomey effect j
    ~^. 	 A^_^» 	 ' ^ 	 \ 	 / 	
    Surface
    ^•-- •*?!>' Indirect effect_ ""•' •".;..•
    on ice clouds ""."'.
    and contrails . . "
    Drizzle Increased cloud height Increased cloud Heating causes
    suppression. (Pincus & Baker, 1994) lifetime cloud burn-off
    Increased LWC (Albrecht, 1989) (Ackerman et al., 2000)
    I \Cloud lifetime effect/ 2nd indirect effect/ Albrecht effect J I Semi-direct effect I
    
    
                                                           Source: IPCC (2007, 092765) modified from Haywood and Boucher (2000,156531).
    
    Figure 9-52.    Aerosol radiative forcing. Airborne particles can affect the heat balance of the
                    atmosphere, directly, by scattering and absorbing sunlight, and indirectly, by
                    altering cloud brightness and possibly lifetime. Here small black dots represent
                    aerosols, circles represent cloud droplets, and straight lines represent short-
                    wave radiation, and wavy lines, long-wave radiation. LWC is liquid water content,
                    and CDNC is cloud droplet number concentration. Confidence in the magnitudes
                    of these effects varies considerably (see Chapter 3). Although the overall effect of
                    aerosols is a net cooling at the surface, the heterogeneity of particle spatial
                    distribution, emission history, and  properties, as well as differences in surface
                    reflectance, mean that the magnitude and even the sign of aerosol effects vary
                    immensely with location, season and sometimes inter-annually. The human-
                    induced component of these effects is sometimes called "climate forcing."
    
                    Several variables are used to quantify the impact aerosols have on Earth's energy balance;
                these are helpful in describing current understanding, and in assessing possible future steps.
                    For the purposes of this report, aerosol radiative forcing (KF) is defined as the net energy
                flux (downwelling minus upwelling) difference between an initial and a perturbed aerosol
                loading state, at a specified level in the atmosphere. (Other quantities, such as solar radiation,
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                 are assumed to be the same for both states.) This difference is defined such that a negative
                 aerosol forcing implies that the change in aerosols relative to the initial state exerts a cooling
                 influence, whereas a positive forcing would mean the change in aerosols exerts a warming
                 influence.
                     There are a number of subtleties associated with this definition:
                     (1) The initial state against which aerosol forcing is assessed must be specified. For direct
                 aerosol radiative forcing, it is sometimes taken as the complete absence of aerosols. IPCC AR4
                 (2001, 156587) uses as the initial state their estimate of aerosol loading in 1750. That year is
                 taken as the approximate beginning of the era when humans exerted accelerated influence on
                 the environment.
                     (2) A distinction must be made between aerosol RF and the anthropogenic contribution to
                 aerosol RF. Much effort has been made to distinguishing these contributions by modeling and
                 with the help of space-based, airborne, and surface-based remote sensing, as well as in situ
                 measurements. These efforts are described in subsequent chapters (of the CCSP SAP2.3).
                     (3) In general, aerosol RF and anthropogenic aerosol RF include energy associated with
                 both the shortwave (solar) and the long-wave (primarily planetary thermal infrared)
                 components of Earth's radiation budget. However, the solar component typically dominates, so
                 in this document, these terms are used to refer to the solar component only, unless specified
                 otherwise. The wavelength separation between the short- and long-wave components is usually
                 set at around three or four micrometers.
                     (4) The IPCC AR4 (2007, 092765) defines radiative forcing as the net downward minus
                 upward irradiance at the tropopause due to an external driver of climate change. This
                 definition excludes stratospheric contributions to the overall forcing. Under typical conditions,
                 most aerosols are located within the troposphere,  so aerosol forcing at TOA and at the
                 tropopause are expected to be very similar. Major volcanic eruptions or conflagrations can
                 alter this picture regionally, and even globally.
                     (5) Aerosol radiative forcing can be evaluated at the surface, within the atmosphere, or at
                 top-of-atmosphere (TOA). In this document, unless specified otherwise, aerosol radiative
                 forcing is assessed at TOA.
                     (6) As discussed subsequently, aerosol radiative forcing can be greater at the surface than
                 at TOA if the aerosols absorb solar radiation.  TOA forcing affects the radiation budget of the
                 planet. Differences between TOA forcing and surface forcing represent heating within the
                 atmosphere that can affect vertical stability, circulation on many scales, cloud formation, and
                 precipitation, all  of which are climate effects  of aerosols. In this document, unless specified
                 otherwise, these additional climate effects are not included in aerosol radiative forcing.)
                     (7) Aerosol direct radiative forcing can be evaluated under cloud-free conditions or under
                 natural conditions, sometimes termed "all-sky" conditions, which include clouds. Cloud-free
                 direct aerosol forcing is more easily and more accurately calculated; it is generally greater than
                 all-sky forcing because clouds can mask the aerosol contribution to the scattered light. Indirect
                 forcing, of course, must be evaluated for cloudy or all-sky conditions. In this document, unless
                 specified otherwise, aerosol radiative  forcing is assessed for all-sky conditions.
                     (8) Aerosol radiative forcing can be evaluated instantaneously, daily (24 h) averaged, or
                 assessed over some other time period. Many measurements, such as those from polar-orbiting
                 satellites, provide instantaneous values, whereas models usually consider aerosol RF as a daily
                 average quantity. In this document, unless specified otherwise, daily averaged aerosol radiative
                 forcing is reported.
                     (9) Another  subtlety is the distinction between a "forcing" and a "feedback." As different
                 parts of the climate system interact, it is often unclear which elements are "causes" of climate
                 change (forcings among them), which are responses to these causes, and which might be some
                 of each. So, for example, the concept  of aerosol effects on clouds is complicated by the impact
                 clouds have on aerosols; the aggregate is often called aerosol-cloud interactions. This
                 distinction sometimes matters, as it is more natural to attribute responsibility for causes than
                 for responses. However, practical environmental considerations usually depend on the net
                 result of all influences.  In this report, "feedbacks" are taken as the consequences of changes in
                 surface or atmospheric  temperature, with the understanding that for some  applications, the
                 accounting may be done differently.
    December 2009                                          9-76
    

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            RF Terms
                                                       RF values (W m"2)
    Spatial scale
    LOSU
               Long-lived
        greenhouse gases"
                   Ozone
    
         Stratospheric water
          vapour from CH4
    
            Surface albedo
                {Direct effect
    
    
               Cloud albedo
                    effect
    
    
            Linear contrails
                                                       1.66 [1.49 to 1.83]
    
                                                       0.48 [0.43 to 0.53]
                                                       0.16 [0.14 to 0.18]
                                                       0.34 [0.31 to 0.37]
    
                                                       -0.05 [-0.15 to 0.05]
                                                       0.35 [0.25 to 0.65]
    
                                                       0.07 [0.02 to 0.12]
    
    
                                                        -0.2 [-0.4 to 0.0]
                                                         0.1 [0.0 to 0.2]
    
    
                                                        -0.5 [-0.9 to-0.1]
    
    
                                                       -0.7 [-1.8 to -0.3]
    
    
                                                       0.01 [0.003 to 0.03]
                                                                                         Global
       Global
    
    
     Continental
      to global
    
    
       Global
    
    
      Local to
     continental
    
     Continental
      to global
    
     Continental
      to global
    
    
     Continental
     High
    
    
    
     High
    
    
    
     Med
    
    
    
     Low
    
    
     Med
     - Low
    
    
     Med
     - Low
    
    
     Low
    
    
    
     Low
            Solar irradiance
                                                                       0.12 [0.06 to 0.30]
                                                                                         Global
                                                                                                   Low
                 Total net
             anthropogenic
                                                         1.6 [0.6 to 2.4]
                        -2-101
                                Radiative Forcing (W nrr2)
                                                                                         Source: IPCC (2007, 092765).
    Figure 9-53.
    Global average radiative forcing (RF) estimates and uncertainty ranges in 2005,
    relative to the pre-industrial climate.  Anthropogenic C02, methane (ChU), nitrous
    oxide (N20), ozone, and aerosols as well as the natural solar irradiance variations
    are included. Typical geographical extent  of the forcing (spatial scale) and the
    assessed level  of scientific understanding (LOSU) are also given. Forcing is
    expressed in units of watts per square meter (W/m2). The total anthropogenic
    radiative forcing and its associated uncertainty are also given.
    December 2009
                                      9-77
    

    -------
                .a
                 CO
                .a
                 o
                .i   1
                 CD
                cc
    Total aerosol
    •adiative forcing    -
                                                cooling
                                                         warming
                  Long-lived greenhouse ,
                  gases and ozone      i
                  radiative forcings      i
                   1           '       •
    Total anthropogenic radiative forcing  i
                                     i
                                     i
                                    i
                                                                  ii
                                                                  n
                                                                  n
    
                                                                   i
                                                                   i
                    Ok
                     -3
                     -1          0          1
                    Radiative Forcing  (W nr2)
                                                                                      Source: Adapted from IPCC (2007, 0927651.
    Figure 9-54.    Probability distribution functions (PDFs) for anthropogenic aerosol and GHG
                     RFs. Dashed red curve:  RF of long-lived greenhouse gases plus ozone; dashed
                     blue curve: RF of aerosols (direct and cloud albedo RF); red filled curve:
                     combined anthropogenic RF. The RF range is at the 90% confidence interval.
    
                     In summary, aerosol radiative forcing, the fundamental quantity about which this report is
                written, must be  qualified by specifying the initial and perturbed aerosol states for which the
                radiative flux difference is calculated, the altitude at which the quantity is assessed, the
                wavelength regime considered, the temporal averaging, the cloud conditions, and whether total
                or only human-induced contributions are considered. The definition given here, qualified as
                needed, is used throughout the report.
                     Although the possibility that aerosols affect climate was recognized more than 40 years
                ago, the measurements needed to establish the magnitude of such effects, or even whether
                specific aerosol types warm or cool the surface, were lacking. Satellite instruments capable of
                at least crudely monitoring aerosol amount globally were first deployed in the late 1970s. But
                scientific focus on this subject grew substantially in the 1990s (e.g., Charlson and Wigley,
                1994, 189989: Charlson et al, 1991, 045793: 1992, 045794: Penner et al, 1992, 045825), in
                part because it was recognized that reproducing the observed temperature trends over the
                industrial period  with climate models requires including net global cooling by aerosols in the
                calculation (IPCC, 1995, 190991: 1996,190990), along with the warming influence of
                enhanced atmospheric greenhouse gas (GHG) concentrations - mainly carbon dioxide,
                methane, nitrous oxide, chlorofluorocarbons, and ozone.
                     Improved satellite instruments,  ground- and ship-based surface monitoring, more
                sophisticated chemical transport  and climate models, and field campaigns that brought all
                these elements together with aircraft remote sensing and in situ sampling for focused,
                coordinated study, began to fill in some of the knowledge gaps. By the Fourth IPCC
                Assessment Report, the scientific community consensus held that in global average, the sum of
                direct and indirect top-of-atmosphere (TOA) forcing by anthropogenic aerosols is negative
                (cooling) of about -1.3 W/m2 (-2.2 to -0.5 W/m2). This is significant compared to the positive
                forcing by anthropogenic GHGs  (including ozone), about 2.9 ± 0.3 W/rri (IPCC, 2007,
                092765). However, the spatial distribution of the gases and aerosols are very different, and
                they do not simply exert compensating influences on climate.
                     The IPCC aerosol forcing assessments are based largely on model calculations,
                constrained as much as possible by observations. At present, aerosol influences are not yet
                quantified adequately, according to Figure 9-53, as scientific understanding is designated as
                "Medium-Low" and "Low" for the direct and indirect climate forcing, respectively. The IPCC
                AR4 (2007, 092765) concluded that uncertainties associated with changes in Earth's radiation
                budget due to anthropogenic aerosols make the largest contribution to the overall uncertainty
                in radiative forcing of climate change among the factors assessed over the industrial period
                (Figure 9-54).
    December 2009
                                   9-78
    

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                        -20
                              South    Smiin   A-CO.I    A-n.z  A -0.3-   Harm   Łur0p«    e«al
                             Artivrica   Africa                       0.35   Amorica
    
                             BkHnii&s burning         Mineral dust                  Pollution
    
                                               Source: Adapted with Permission of theAmerican Geophysical Union from from Zhou et al. (2005, 1561831.
    Figure 9-55.    The clear-sky forcing efficiency ET, defined as the diurnally averaged aerosol
                     direct radiative effect (W/m2) per unit AOD at 550 nm, calculated at both TOA and
                     the surface, for typical aerosol types over different geographical regions. The
                     vertical black lines represent ± one standard deviation of ET for individual aerosol
                     regimes and A is surface broadband albedo.
    
                     Although AOD, aerosol properties, aerosol vertical distribution, and surface reflectivity
                all contribute to aerosol radiative forcing, AOD usually varies on regional scales more than the
                other aerosol quantities involved. Forcing efficiency (Ex), defined as a ratio of direct aerosol
                radiative forcing to AOD at 550 nm, reports the sensitivity of aerosol radiative forcing to
                AOD, and is useful for isolating the influences of particle properties  and other factors from
                that of AOD. ET is expected to exhibit a range of values globally, because it is governed
                mainly by aerosol size distribution and chemical composition (which determine aerosol single-
                scattering albedo and phase function), surface reflectivity, and solar irradiance, each of which
                exhibits pronounced spatial and temporal variations. To assess aerosol RF, ET is multiplied by
                the ambient AOD.
                     Figure 9-55 shows a range of ET, derived from AERONET surface sun photometer
                network measurements of aerosol loading and particle properties, representing different
                aerosol and surface types, and geographic locations. It demonstrates how aerosol direct solar
                radiative forcing (with initial state taken as the absence of aerosol) is determined by a
                combination of aerosol and surface properties. For example, ET due to southern African
                biomass burning smoke is greater at the surface and smaller at TOA than South American
                smoke because the southern African smoke absorbs sunlight more strongly, and the magnitude
                of ET for mineral dust for several locations varies depending on the underlying surface
                reflectance. Figure 9-55  illustrates one further point, that the radiative forcing by aerosols on
                surface energy balance can be much greater than that at TOA. This is especially true when the
                particles have SSA substantially less than 1, which can create differences between surface and
                TOA forcing as large as a factor of five (e.g., Zhou et al., 2005, 156183).
    December 2009
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     Table 9-3.    Top-of-atmosphere, cloud-free, instantaneous direct aerosol radiative forcing
                  dependence on aerosol and surface properties.  Here TWP, SGP, and  NSA are the
                  Tropical West Pacific island, Southern Great Plains, and North Slope Alaska
                  observation stations maintained by the DOE ARM program, respectively.
                  Instantaneous values are given at specific solar zenith angle. Upper and middle
                  parts are from McComiskey et al. (2008,190523). Representative, parameter-
                  specific measurement uncertainty upper bounds  for producing 1 W/m2
                  instantaneous TOA forcing accuracy are given in  the  lower part, based on
                  sensitivities at three sites from the middle part of the table.
    
    
    	Parameters	TWP	SGP	NSA	
    
     AEROSOL PROPERTIES (AOD, SSA, G), SOLAR ZENITH ANGLE (SZA), SURFACE ALBEDO (A), AND AEROSOL DIRECT RF AT
     TOA (F)
    
     AOD                        0.05                       0.1                        0.05
    
     SSA                        0.97                       0.95                       0.95
    
     g                           0.8                        0.6                        0.7
    
     A                           0.05                       0.1                        0.9
    
     SZA                        30                        45                        70
    
     F(W/m2)                      -2.2                       -6.3                       2.6
    
     SENSITIVITY OF CLOUD-FREE, INSTANTANEOUS, TOA DIRECT AEROSOL RADIATIVE FORCING TO AEROSOL AND SURFACE
     PROPERTIES, W/fif PER UNIT CHANGE IN PROPERTY
    
     dFld(AOD)                     -45                        -64                        51
    
     dFld(SSA)                     -11                        -50                        -60
    
     dFldg                        13                        23                        2
    
     dFldA                        8                         24                        6
    
     REPRESENTATIVE MEASUREMENT UNCERTAINTY UPPER BOUNDS FOR PRODUCING  1 W/M2 ACCURACY OF AEROSOL RF
    
     AOD                        0.022                      0.016                      0.020
    
     SSA                        0.091                      0.020                      0.017
    
     g                           0.077                      0.043
    
     A                           0.125                      0.042                      0.167
    
    
                    Table 9-3 presents estimates of cloud-free, instantaneous, aerosol direct RF dependence
                on AOD, and on aerosol and surface properties, calculated for three sites maintained by the
                U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) program, where
                surface and  atmospheric conditions span a significant range of natural environments
                (McComiskey et al., 2008, 190523). Here aerosol RF is evaluated relative to an initial state
                that is the complete absence of aerosols. Note that aerosol direct RF dependence on individual
                parameters varies considerably, depending on the values of the  other parameters, and in
                particular, that aerosol RF dependence on AOD actually changes  sign, from net cooling to net
                warming, when aerosols reside over an exceedingly bright surface. Sensitivity values are given
                for snapshots at fixed solar zenith angles, relevant to measurements made, for example, by
                polar-orbiting satellites.
                    The lower portion of Table 9-3 presents upper bounds on instantaneous measurement
                uncertainty,  assessed individually for each of AOD, SSA, g, and A, to produce a 1 W/m2 top-of
                atmosphere, cloud-free aerosol RF accuracy. The values are derived from the upper portion of
                the table, and reflect the diversity of conditions captured by the three ARM sties. Aerosol RF
                sensitivity of 1 W/m2 is used as an example; uncertainty upper bounds are obtained from the
                partial derivative for each parameter by neglecting the uncertainties for all other parameters.
                These estimates produce an instantaneous AOD measurement uncertainty upper bound
                between about 0.01 and 0.02, and SSA constrained to about 0.02 over  surfaces as bright as or
                brighter than the ARM Southern Great Plains site, typical of mid-latitude, vegetated land.
                Other researchers, using independent data sets, have derived ranges of ET and aerosol RF
     December 2009                                      9-80
    

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                 sensitivity similar to those presented here, for a variety of conditions (Christopher and Jones,
                 2008, 189985: Yu et al, 2006, 156173: Zhou et al, 2005, 156183).
                     These uncertainty bounds provide a baseline against which current and expected near-
                 future instantaneous measurement capabilities are assessed in Chapter 2 (of the CCSP
                 SAP2.3). Model sensitivity is usually evaluated for larger-scale (even global) and longer-term
                 averages.  When instantaneous measured values from a randomly sampled population are
                 averaged, the uncertainty component associated with random error diminishes as something
                 like the inverse square root of the number of samples. As a result, the accuracy limits used for
                 assessing more broadly averaged model results corresponding to those used for assessing
                 instantaneous measurements would have to be tighter, as discussed in Chapter 4 (of the CCSP
                 SAP2.3).
                     In summary, much of the challenge in quantifying aerosol influences arises from large
                 spatial and temporal heterogeneity, caused by the wide variety of aerosol sources, sizes and
                 compositions, the spatial non-uniformity and intermittency of these sources, the short
                 atmospheric lifetime of most aerosols, and the spatially and temporally non-uniform chemical
                 and microphysical processing that occurs in the atmosphere. In regions having high
                 concentrations of anthropogenic aerosol, for example, aerosol forcing is much stronger than
                 the global average, and can exceed the magnitude of GHG warming, locally reversing the sign
                 of the net forcing. It is also important to recognize that the global-scale aerosol TOA forcing
                 alone is not an adequate metric for climate change (NRC, 2005, 057409). Due to aerosol
                 absorption, mainly by soot, smoke, and some desert dust particles, the aerosol direct radiative
                 forcing at the surface can be much greater than the TOA forcing, and in addition, the radiative
                 heating of the atmosphere by absorbing particles can change the atmospheric temperature
                 structure,  evolution, and possibly large-scale dynamical systems such as the monsoons (Kim et
                 al., 2006,  190917: Lau et al., 2009, 190229). By realizing aerosol's climate significance and
                 the challenge of charactering highly variable aerosol amount and properties, the U.S. Climate
                 Change Research Initiative (CCPJ) identified research on atmospheric concentrations and
                 effects of aerosols specifically as a top priority (NRC, 2001, 053303.).
    
    
    
    9.3.2.  Overview of Aerosol  Measurement Capabilities
    
    
    
    9.3.2.1.    Satellite Remote Sensing
    
           Section 9.3.2  with the exception of the final  paragraph, comes directly  from CCSP SAP2.3
    Chapter 2, Section 2.2 with  section, table, and figure numbers changed to be internally consistent
    with this ISA.
                     A measurement-based characterization of aerosols on a global scale can be realized only
                 through satellite remote sensing, which is the only means of characterizing the large spatial
                 and temporal heterogeneities of aerosol distributions. Monitoring aerosols from space has been
                 performed for over two decades and is planned for the coming decade with enhanced
                 capabilities (Forster et al., 2007, 092936: King et al., 1999, 190635: Lee et al., 2006, 190358:
                 Mischenko et al., 2007, 190543). Table 9-4 summarizes major satellite measurements currently
                 available for the tropospheric aerosol characterization and radiative forcing research.
                     Early aerosol monitoring from space relied on sensors that were designed for other
                 purposes.  The Advanced Very High Resolution Radiometer (AVHRR),  intended as a cloud and
                 surface monitoring instrument, provides radiance observations in the visible and near infrared
                 wavelengths that are sensitive to aerosol properties over the ocean (Husar et al., 1997, 045900:
                 Mishchenko et al., 1999,  190541). Originally intended for ozone monitoring, the ultraviolet
                 (UV) channels used for the Total Ozone Mapping Spectrometer (TOMS) are sensitive to
                 aerosol UV absorption with little surface interferences, even over land (Torres et al., 1998,
                 190503). This UV-technique makes TOMS suitable for monitoring biomass burning smoke
                 and dust, though with limited sensitivity near the  surface (Herman et al., 1997, 048393) and
                 for retrieving aerosol single-scattering albedo from space (Torres et al., 2005, 190507). (Anew
                 sensor, the Ozone Monitoring Instrument (OMI) aboard Aura, has improved on such UV-
                 technique advantages, providing higher spatial resolution and more spectral channels; see
                 (Veihelmann et al., 2007, 190627). Such historical sensors have provided multi-decadal
                 climatology of aerosol optical depth that has significantly advanced the understanding of
                 aerosol distributions and long-term variability (e.g.,Geogdzhayev et al., 2002, 190574: Massie
                 et al., 2004,  190492: Mishchenko and Geogdzhayev, 2007, 190545: Mishchenko et al., 2007,
                 190542: Torres et al., 2002,  190505: Zhao et al., 2008, 190935).
                     Over the past decade, satellite aerosol retrievals have become increasingly sophisticated.
                 Now, satellites measure the angular dependence of radiance and polarization at multiple
                 wavelengths from UV through the infrared (IR) at fine spatial resolution. From these
                 observations, retrieved aerosol products include not only optical depth at one wavelength, but
                 also spectral optical depth and some information about particle size over both ocean and land,
                 as well as more direct measurements of polarization and phase function. In addition, cloud
                 screening is much more robust than before and onboard calibration is now widely available.
    December 2009                                        9-81
    

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                Examples of such new and enhanced sensors include the MODerate resolution Imaging
                Spectroradiometer (MODIS, see Box 2.1 of CCSP SAP2.3), the Multi-angle Imaging
                SpectroRadiometer (MISR, see Box 2.2 of CCSP SAP2.3), Polarization and Directionality of
                the Earth's Reflectance (POLDER, see Box  2.3 of CCSP SAP2.3), and OMI, among others.
                The accuracy for AOD measurement from these sensors is about 0.05 or 20% of AOD (Kahn
                et al, 2005, 190966: Remer et al, 2005, 190221) and somewhat better over dark water, but
                that for aerosol microphysical properties, which is useful for distinguishing aerosol air mass
                types, is generally low. The Clouds and the Earth's Radiant Energy System (CERES, see Box
                2.4 of CCSP SAP2.3) measures broadband solar and terrestrial radiances. The CERES
                radiation measurements in combination with satellite retrievals of aerosol optical depth can be
                used to determine aerosol direct radiative forcing.
    Table 9-4.    Summary of major satellite measurements currently available for the tropospheric
                  aerosol characterization and radiative forcing research.
    Category Properties Sensor/platform
    AVHRR/NOAA-series
    TOMS/Nimbus,ADEOSI, EP
    POLDER-1, 2, PARASOL
    Loading MODISATerra.Aqua
    MISR/Terra
    OMI/Aura
    AVHRR/NOAA-series
    Column-integrated POLDER-1 ,2, PARASOL
    Size, shape MODIS/Terra.Aqua
    Parameters
    
    
    
    Optical depth
    
    
    Angstrom exponent
    Fine-mode fraction,
    Angstrom exponent,
    non-spherical fraction
    Fine-mode fraction
    Angstrom exponent
    Effective radium
    Asymmetry factor
    Spatial coverage
    ~daily coverage of
    global ocean
    -daily coverage of
    global land and ocean
    -weekly coverage of
    global land and ocean,
    including bright desert
    and nadir sun-glint
    -daily coverage of
    global land and ocean
    Global ocean
    Global land and ocean
    Global land and ocean
    ocean)
    
    
    Temporal coverage
    1981 -present
    1979-2001
    1997-present
    2000-present (Terra)
    2002-present (Aqua)
    2000-present
    2005-present
    1981 -present
    1997-present
    2000-present (Terra)
    2002-present (Aqua)
                                    MISR/Terra
      Angstrom exponent,
      small, medium large
      fractions, non-spherical
      fractions
                                                                            Global land and ocean   2000-present
    TOMS/Nimbus,ADEOSI, EP
    Absorption OMI/Aura
    MISR/Terra
    GLAS/ICESat
    Vertical-resolved shape"9' °IZ°' ^
    CALIOP/CALIPSO
    Absorbing aerosol index,
    absorbing optical depth
    Single-scattering albedo
    (2-4 bins)
    Extinction/backscatter
    Extinction/backscatter,
    color ratio,
    depolarization ratio
    Global land and ocean
    Global land and ocean,
    • 16-day repeating cycle,
    single-nadir
    measurement
    1979-2001
    2005-present
    2000-present
    2003-present
    (-3 mo/yr)
    2006-present
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                     Complementary to these passive sensors, active remote sensing from space is also now
                 possible and ongoing (see Box 2.5 of CCSP SAP2.3). Both the Geoscience Laser Altimeter
                 System (GLAS) and the Cloud and Aerosol Lidar with Orthogonal Polarization (CALIOP) are
                 collecting essential information about aerosol vertical distributions. Furthermore, the
                 constellation of six afternoon-overpass spacecrafts (as illustrated in Figure 9-60), the so-called
                 A-Train (Stephens et al., 2002, 190412) makes it possible for the first time to conduct near
                 simultaneous (within 15 minutes) measurements of aerosols, clouds, and radiative fluxes in
                 multiple dimensions with  sensors in complementary capabilities.
                     The improved accuracy of aerosol products (mainly AOD) from these new-generation
                 sensors, together with improvements in characterizing the earth's surface and clouds, can help
                 reduce the uncertainties associated with estimating the aerosol direct radiative forcing (Yu et
                 al., 2006, 156173): and references therein). The retrieved aerosol microphysical properties,
                 such as size, absorption, and non-spherical fraction can help distinguish anthropogenic
                 aerosols from natural aerosols and hence help assess the anthropogenic component of aerosol
                 direct radiative forcing (Bellouin et al., 2005, 155684; Christopher et al., 2006, 155729;
                 Kaufman et al., 2005, 155891: Yu et al., 2006, 156173). However, to infer aerosol number
                 concentrations and examine indirect aerosol radiative effects from space, significant efforts are
                 needed to measure  aerosol size distribution with much improved accuracy, characterize aerosol
                 type, account for impacts of water uptake on aerosol optical depth, and determine the fraction
                 of aerosols that is at the level of the clouds (Kapustin et al., 2006, 190961: Rosenfeld, 2006,
                 190233). In addition, satellite remote sensing is not sensitive to particles much smaller than
                 0.1 micrometer in diameter, which comprise  of a significant fraction of those that serve as
                 cloud condensation nuclei.
                     Finally, algorithms are being developed to retrieve aerosol absorption or SSA from
                 satellite observations (e.g., Kaufman et al., 2002, 190955: Torres et al., 2005, 190507). The
                 NASA Glory mission, scheduled to launch in 2009 and to be added to the A-Train, will deploy
                 a multi-angle, multispectral polarimeter to determine the global distribution of aerosol and
                 clouds. It will also be able to infer microphysical property information, from which aerosol
                 type (e.g., marine, dust, pollution, etc.) can be inferred for improving quantification of the
                 aerosol direct and indirect forcing on climate (Mischenko et al., 2007, 190543).
                     In summary, major advances have been made in both passive and active aerosol remote
                 sensing from space in the past decade, providing better coverage, spatial resolution, retrieved
                 AOD  accuracy, and particle property information. However, AOD accuracy is still much
                 poorer than that from surface-based sun photometers (0.01-0.02), even over vegetated land and
                 dark water where retrievals are most reliable. Although there is some hope of approaching this
                 level of uncertainty with a new generation of satellite instruments, the satellite retrievals  entail
                 additional sensitivities to aerosol and surface scattering properties.  It seems unlikely that
                 satellite remote sensing could exceed the sun photometer accuracy without introducing some
                 as-yet-unspecified new technology. Spacebased lidars are for the first time providing global
                 constraints on aerosol vertical distribution, and multi-angle imaging is supplementing this with
                 maps  of plume injection height in aerosol source regions. Major advances have also been made
                 during the past decade in distinguishing aerosol types from space, and the data are now useful
                 for validating aerosol transport model simulations of aerosol air mass type distributions and
                 transports, particularly over dark water. But particle size, shape, and especially SSA
                 information has large uncertainty; improvements will be needed to better distinguish
                 anthropogenic from natural aerosols using space-based retrievals. The particle microphysical
                 property detail required to assess aerosol radiative forcing will come largely from targeted in
                 situ and surface remote sensing measurements, at least for the near-future, although estimates
                 of measurement-based aerosol RF can be made from judicious use of the satellite data with
                 relaxed requirements for characterizing aerosol microphysical properties.
    
    
           MODerate resolution Imaging Spectroradiometer
    
                     MODIS performs near global daily observations of atmospheric aerosols. Seven of 36
                 channels (between  0.47 and 2.13 um) are used to retrieve aerosol properties over cloud and
                 surface-screened areas (Li et al., 2004,  190386: Martins et al., 2002, 190470). Over vegetated
                 land, MODIS retrieves aerosol optical depth at three visible channels with high accuracy of ±
                 0.05 ± 0.2x (Chu et al., 2002, 190001: Kaufman  and Fraser, 1997,  190958: Levy et al., 2007,
                 190379: Remer et al., 2005, 190221). Most recently a deep blue algorithm (Hsu et al., 2004,
                 190622) has been implemented to retrieve aerosols  over bright deserts on an operational basis,
                 with an estimated accuracy of 20-30%. Because of the greater simplicity of the ocean surface,
                 MODIS has the unique capability of retrieving not only aerosol optical depth with greater
                 accuracy, i.e., ± 0.03 ± O.OSx (Remer et al., 2002, 190218: 2005, 190221: Remer et al., 2008,
                 190224: Tanre et al., 1997, 190452), but also quantitative aerosol size parameters (e.g.,
                 effective radius, fine-mode fraction of AOD) (Kaufman et al., 2002, 190956: Kleidman et al.,
                 2005, 190175: Remer et al., 2005, 190221). The fine-mode fraction has been used as a tool for
                 separating anthropogenic aerosol from natural ones and estimating the anthropogenic aerosol
                 direct climate forcing (Kaufman et al., 2005, 155891). Figure 9-56 shows composites of
                 MODIS AOD and fine-mode fraction that  illustrate seasonal and geographical variations of
                 aerosol types. Clearly seen from the figure is heavy pollution over East Asia in both months,
                 biomass burning smoke over South Africa, South America, and Southeast Asia in August,
    December 2009                                         9-83
    

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                heavy dust storms over North Atlantic in both months and over Arabian Sea in August, and a
                mixture of dust and pollution plume swept across North Pacific in April.
    
    
           Multi-Angle Imaging SpectroRadiometer
    
                     MISR, aboard the sun-synchronous, polar orbiting satellite Terra, measures upwelling
                solar radiance in four visible-near-IR spectral bands and at nine view angles spread out in the
                forward and aft directions along the flight path (Diner et al, 2002, 189967). It acquires global
                coverage about once per week. A wide range of along-track view angles makes it feasible to
                more accurately evaluate the surface contribution to the TOA radiances and hence retrieve
                aerosols over both ocean and land surfaces, including bright desert and sunglint regions (Diner
                et al., 1998, 189962; Kahn et al., 2005, 190966; Martonchik et al., 1998, 190472; 2002,
                190490). MISR AODs are within 20% or ± 0.05 of coincident AERONET measurements
                (Abdou et al., 2005, 190028; Kahn et al., 2005, 189961). The MISR multi-angle data also
                sample scattering angles ranging from about 60° to 160° in midlatitudes, yielding information
                about particle size (Chen et al., 2008, 189984; Kahn et al., 1998,  190970; 2001, 190969;  2005,
                190966) and shape (Kalashnikova  and Kahn, 2006, 190962). The aggregate of aerosol
                microphysical properties can be used to assess aerosol airmass type, a more robust
                characterization of MISR-retrieved particle property information than individual attributes.
                MISR also retrieves plume height in the vicinity of wildfire, volcano, and mineral dust aerosol
                sources, where the plumes have discernable spatial contrast in the multi-angle imagery (Kahn
                et al., 2007, 190964). Figure 9-57 is an example that illustrates MISR's ability to characterize
                the load, optical properties, and stereo height of near-source fire plumes.
    
    
           POLarization  and Directionality of the Earth's Reflectance
    
                     POLDER is a unique aerosol sensor that consists of wide field-of-view imaging spectro-
                radiometer capable of measuring multi-spectral, multi-directional, and polarized radiances
                (Deuze et al., 2001, 192013). The observed radiances can be  exploited to better separate the
                atmospheric contribution from the surface contribution over both land and ocean. POLDER -1
                and -2 flew onboard the ADEOS (Advanced  Earth Observing Satellite) from November 1996
                to June 1997 and April to October of 2003, respectively. A similar POLDER instrument flies
                on the PARASOL satellite that was launched in December 2004.
                     Figure 9-58 shows global horizontal patterns of AOD and Angstrom exponent over the
                oceans derived  from the  POLDER instrument for June 1997. The oceanic AOD map (Figure
                9-58a) reveals near-coastal plumes of high AOD, which decrease with distance from the coast.
                This pattern arises from aerosol emissions from the continents, followed by atmospheric
                dispersion, transformation, and removal in the downwind direction. In large-scale flow fields,
                such as the trade winds, these continental plumes persist over several thousand kilometers. The
                Angstrom exponent shown in Figure 9-58 exhibits a very different pattern from that of the
                aerosol optical depth; specifically, it exhibits high values downwind of industrialized regions
                and regions of biomass burning, indicative of small particles  arising from direct emissions
                from combustion sources and/or gas-to-particle conversion, and low values associated with
                large particles in plumes of soil dust from deserts and in sea salt aerosols.
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                                          Source: Adapted from (Chin et al., 2007,1900621: original figure from Yoram Kaufman and Reto Stockli.
    
    Figure 9-56.   A composite of MODIS/Terra observed aerosol optical depth (at 550 nm, green
                  light near the peak of human  vision) and fine-mode fraction that shows spatial
                  and seasonal variations of aerosol types.  Industrial pollution and biomass
                  burning aerosols are predominately small particles (shown as red), whereas
                  mineral dust and sea salt consist primarily of large particles (shown as green).
                  Bright red and bright green indicate heavy pollution and dust plumes,
                  respectively.
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                                                Source: Reprinted with Permission of theAmerican Geophysical Union from Kahn et al. (2007,190964).
    Figure 9-57.   Oregon fire on September 4,2003, as observed by MISR: (a) MISR nadir view of
                    the fire plume, with five patch locations numbered and wind-vectors superposed
                    in yellow; (b) MISR aerosol optical depth  at 558 nm; and (c) MISR stereo height
                    without wind correction for the same region.
    9.3.2.2.   Focused Field Campaigns
    
                    Over the past two decades, numerous focused field campaigns have examined the
                physical, chemical, and optical properties and radiative forcing of aerosols in a variety of
                aerosol regimes around the world, as listed in Table 9-5. These campaigns, which have been
                designed with aerosol characterization as the main goal or as one of the major themes in more
                interdisciplinary studies, were conducted mainly over or downwind of known continental
                aerosol source regions, but in some instances in low-aerosol regimes, for contrast. During each
                of these comprehensive campaigns, aerosols were studied in great detail, using combinations
                of in situ and remote sensing observations of physical and chemical properties from various
                platforms (e.g., aircraft, ships, satellites, and ground-based stations) and numerical modeling.
                In spite of their relatively short duration, these field studies have acquired comprehensive data
                sets of regional aerosol properties that have been used to understand the properties and
                evolution of aerosols within the atmosphere and to improve the climatology of aerosol
                microphysical properties used in satellite retrieval algorithms and CTMs.
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              Optical Depth
                \ - 865 nm
          Angstrom Exponent
            •x = -d  In  rid In K
    -0.2
                  Source: Reproduced with permission of Laboratoire d'Optique Atmospherique (LOA), Lille, FR; Laboratoire des Sciences du Climat et de I'Environnement
                       (LSCE), Gif sur Yvette, FR; Centre National d'etudes Spatiales (ONES), Toulouse, FR; and NAtional Space Development Agency (NASDA), Japan.
    
    Figure 9-58.   Global maps at 18 km resolution showing monthly average  (a) AOD at 865 nm
                    and (b) Angstrom exponent  of AOD over water surfaces only for June, 1997,
                    derived from radiance measurements by the POLDER.
    9.3.2.3.   Ground-Based In Situ Measurement Networks
    
                    Major U.S.-operated surface in situ and remote sensing networks for tropospheric aerosol
                characterization and climate forcing research are listed in Table 9-6. These surface in situ
                stations provide information about long-term changes and trends in aerosol concentrations and
                properties, the influence of regional sources on aerosol properties, climatologies of aerosol
                radiative properties, and data for testing models and satellite aerosol retrievals. The NOAA
                Earth System Research Laboratory (ESRL) aerosol monitoring network consists of baseline,
                regional, and mobile stations. These near-surface measurements include submicrometer and
                sub-10 micrometer scattering and absorption coefficients from which the extinction coefficient
                and single-scattering albedo can be derived. Additional measurements include particle
                concentration and, at selected sites, CCN concentration, the hygroscopic growth factor, and
                chemical composition.
                    Several of the stations, which are located across North America and world-wide, are in
                regions where recent focused field campaigns have been conducted. The measurement
                protocols at the stations are similar to those used during the  field campaigns. Hence, the station
                data are directly comparable to the field campaign data so that they provide a longer-term
                measure of mean aerosol properties and their variability, as well as a context for the shorter-
                duration measurements of the field campaigns.
                    The Interagency Monitoring  of Protected Visual Environment (IMPROVE), which is
                operated by the NP Service Air Resources Division, has stations across the U.S. located within
                NPs (Malm et al., 1994, 044920). Although the primary focus of the network is air pollution,
                the measurements are also relevant to climate forcing research. Measurements  include fine and
                coarse mode (PM2.5 and PMi0) aerosol mass concentration; concentrations of elements, sulfate,
                nitrate, organic carbon, and elemental carbon; and scattering coefficients.
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                     In addition, to these U.S.-operated networks, there are other national and international
                 surface networks that provide measurements of aerosol properties including, but not limited to,
                 the World Meteorological Organization (WMO) Global Atmospheric Watch (GAW) network
                 ('http://www.wmo.int/pages/prog/arep/gaw/monitoring.html'), the European Monitoring and
                 Evaluation Programme (EMEP) (http ://wwwemep.int/), the Canadian Air and Precipitation
                 Monitoring Network (CAPMoN) (http://www.msc-smc.ec.gc.ca/capmon/index_e. cfin). and the
                 Acid Deposition Monitoring Network in East Asia (EANET) (http://www.eanet.cc/eanet.html).
    
    
           Clouds and the Earth's Radiant Energy System
    
                     CERES measures broadband solar and terrestrial radiances at three channels with a large
                 footprint (e.g., 20 km for CERES/Terra) (Wielicki et al, 1996, 190637). It is co-located with
                 MODIS and MISR aboard Terra and with MODIS on Aqua. The observed radiances are
                 converted to TOA irradiances or fluxes using the Angular Distribution Models (ADMs) that
                 are functions of viewing angle, sun angle, and scene type (Loeb and Kato,  2002, 190432:
                 Loeb et al., 2005, 190436; Zhang et al., 2005, 190929). Such estimates of TOA solar flux in
                 clear-sky conditions can be compared to the expected flux for an aerosol-free atmosphere, in
                 conjunction with measurements of aerosol optical depth from other sensors (e.g., MODIS and
                 MISR) to derive the aerosol direct radiative forcing (Christopher et al., 2006, 155729: Loeb
                 and Manalo-Smith, 2005, 190433: Patadia et al., 2008, 190558: Zhang and Christopher,  2003,
                 190928: Zhang et al., 2005, 190930). The derived instantaneous value is then scaled to obtain
                 a daily average. A direct use of the coarse spatial resolution CERES measurements would
                 exclude aerosol distributions in partly cloudy CERES scenes. Several approaches that
                 incorporate coincident, high spatial and spectral resolution measurements (e.g., MODIS) have
                 been employed to overcome this limitation (Loeb and Manalo-Smith, 2005, 190433: Zhang et
                 al., 2005, 190930).
    
    
           Active  Remote Sensing of Aerosols
    
                     Following the success of a demonstration of lidar system aboard the U.S. Space Shuttle
                 mission in 1994, i.e., Lidar In-space Technology Experiment (LITE) (Winker et al., 1996,
                 190914), the Geoscience Laser Altimeter System (GLAS) was launched in  early 2003 to
                 become the first polar orbiting  satellite lidar. It  provides global aerosol and cloud profiling for
                 a one-month period out of every three-to-six months. It has been demonstrated that GLAS is
                 capable of detecting and discriminating multiple layer clouds, atmospheric  boundary layer
                 aerosols, and elevated aerosol layers (e.g., Spinhirne et al., 2005, 190410). The Cloud-Aerosol
                 Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), launched on April 28, 2006,
                 is carrying a lidar instrument (Cloud and Aerosol Lidar with Orthogonal Polarization -
                 CALIOP) that has been collecting profiles of the attenuated backscatter at visible and near-
                 infrared wavelengths along with polarized backscatter in the visible channel (Winker et al.,
                 2003,  192017). CALIOP measurements have been used to derive the above-cloud fraction of
                 aerosol extinction optical depth (Chand et al., 2008, 189974), one of the important factors
                 determining aerosol direct radiative forcing in cloudy conditions. Figure 9-59 shows an event
                 of trans-Atlantic transport of Saharan dust captured by CALIPSO. Flying in formation with the
                 Aqua,  AURA, POLDER, and CloudSat satellites, the vertically resolved information is
                 expected to greatly improve passive aerosol and cloud retrievals as  well as allow the retrieval
                 of vertical distributions of aerosol extinction, fine- and coarse-mode separately (Huneeus and
                 Boucher, 2007, 190624: Kaufman et al., 2003,  190954: Leon et al.,  2003, 190366).
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                                               Source: Reprinted with Permission of the American Geophysical Union from Liu et al. (2008,156709).
    
    Figure 9-59.   A dust event that originated in the Sahara desert on 17 August 2007 and was
                   transported to the Gulf of Mexico.  Red lines represent back trajectories
                   indicating the transport track of the dust event. Vertical images are  532 nm
                   attenuated backscatter coefficients measured  by CALIOP when passing  over the
                   dust transport track. The letter "D" designates the dust layer, and "S" represents
                   smoke layers from biomass burning in Africa (17-19 August) and South America
                   (22 August). The track of the high-spectral-resolution-lidar(HSRL) measurement
                   is indicated by the white  line superimposed on the 28 August CALIPSO image.
                   The HSRL track is coincident with the track of the 28 August CALIPSO
                   measurement off the coast of Texas between 28.75°N and 29.08°N.
    9.3.2.4.   In Situ Aerosol Profiling Programs
    
                   In addition to long-term ground based measurements, regular long-term aircraft in situ
               measurements recently have been implemented at several locations. These programs provide a
               statistically significant data set of the vertical distribution of aerosol properties to determine
               spatial and temporal variability through the vertical column and the influence of regional
               sources on that variability. In addition, the measurements provide data for satellite and model
               validation. As part of its long-term ground measurements, NOAA has conducted regular flights
               over Bondville, Illinois since 2006. Measurements include light scattering and absorption
               coefficients, the relative humidity dependence of light scattering, aerosol number
               concentration and size distribution, and chemical composition. The same measurements with
               the exception of number concentration, size distribution, and chemical composition were made
               by NOAA during regular overflights of DOE ARM's Southern Great Plains (SGP) site from
               2000-2007 (Andrews et al., 2004, 190058)
               (http://www.esrl.noaa.gov/gmd/aero/net/index.html).
                   In summary of Sections 9.3.2.2, 9.3.2.3, and 9.3.2.4, in situ measurements of aerosol
               properties have greatly expanded over the past two decades as evidenced by the number of
               focused field campaigns in or downwind of aerosol source regions all over the globe, the
               continuation of existing and implementation of new sampling networks worldwide,  and the
               implementation of regular aerosol profiling measurements from fixed locations. In addition, in
               situ measurement capabilities have undergone major advancements during this same time
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                period. These advancements include the ability to measure aerosol chemical composition as a
                function of size at a time resolution of seconds to minutes (e.g., Jayne et al., 2000, 190978).
                the development of instruments able to measure aerosol absorption and extinction coefficients
                at high sensitivity and time resolution and as a function of relative humidity (e.g., Baynard et
                al., 2007, 151669; Lack et al., 2006, 096032), and the deployment of these instruments across
                the globe on ships, at ground-based sites, and on aircraft. However, further advances are
                needed to make this newly developed instrumentation more affordable and turn-key so that it
                can be deployed more widely to characterize aerosol properties at a variety of sites worldwide.
    Figure 9-60.    A constellation of five spacecraft that overfly the Equatorat about 1:30 p.m., the
                    so-called A-Train, carries sensors  having complementary capabilities, offering
                    unprecedented opportunities to study aerosols from space in multiple
                    dimensions.
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    Table 9-5. List of major intensive field experiments that are relevant to aerosol research in a variety
    of aerosol regimes around the globe conducted in the past two decades.
    Aerosol Regimes
    Anthropogenic aerosol
    and boreal forest from
    North America and West
    Europe
    Brown haze in South Asia
    Anthropogenic aerosol
    and desert dust mixture
    from East Asia
    Biomass burning smoke
    in the tropics
    Mineral dusts from North
    Africa and Arabian
    Peninsula
    Remote oceanic aerosol
    Intensive Field Experiments
    Name
    TARFOX
    NEAQS
    SCAR-A
    CLAMS
    INTEX-NA, ICARTT
    DOEAIOP
    MILAGRO
    TexAQS/GoMACCS
    ARCTS
    ARCTAS
    MINOS
    LACE98
    Aerosols99
    INDOEX
    ABC
    EAST-AIRE
    INTEX-B
    ACE-Asia
    TRACE-P
    PEM-WestA&B
    BASE-A
    SCAR-B
    LBA-SMOCC
    SAFARI2000
    SAFARI92
    TRACE-ADABEX
    DABEX
    SAMUM
    SHADE
    PRIDE
    UAE2
    ACE-1
    Location
    North Atlantic
    North Atlantic
    North America
    East Coast of U.S.
    North America
    Northern Oklahoma
    Mexico City, Mexico
    Texas and Gulf of Mexico
    North-central Alaska to
    Greenland (Arctic haze)
    Northern Canada (smoke)
    Mediterranean region
    Lindberg, Germany
    Atlantic
    Indian subcontinent and
    Indian Ocean
    South and East Asia
    China
    Northeastern Pacific
    East Asian and Northwest
    Pacific
    
    Western Pacific off East
    Asia
    Brazil
    Brazil
    Amazon basin
    South Africa and South
    
    South Atlantic
    West Africa
    Southern Morocco
    West coast of North Africa
    Puerto Rico
    Arabian Peninsula
    Southern Oceans
    Time Period
    July 1996
    July-August 2002
    1993
    July-August 2001
    Summer 2004
    May 2003
    March 2006
    August-September 2006
    March-April 2008
    June-July 2008
    July-August 2001
    July-August 1998
    January-February 1999
    January-April 1 998 & 1999
    Ongoing
    March-April 2005
    April 2006
    April 2001
    March-April 2001
    September-October 1991
    February-March 1994
    1989
    August-September 1995
    September-November
    2002
    August-September 2000
    September-October 1992
    September-October 1992
    January-February 2006
    May-June 2006
    September 2000
    June-July 2000
    August-September 2004
    December 1995
    
    
    Russell etal. (1999. 190363)
    Quinn and Bates (2003, 049189)
    Remer etal. (1997,190216)
    Smith et al. (2005, 190401)
    Fehsenfeld et al. (2006, 190531)
    Ferrare etal. (2006. 190561)
    Molina et al. (2008, 192019)
    Jiang etal. (2008. 156609):
    Lu et al. (2008, 190455)
    http://www.espo.nasa.gov/arctas/
    
    Lelieveld et al. (2002. 190361)
    Ansmann et al. (2002)
    Bates et al. (2001 , 043385)
    Ramanathan et al. (2001 , 190196)
    Ramanathan and Crutzen (2003, 190198)
    Li etal. (2007. 190392)
    Singh et al. (2008, 190394)
    Huebert etal. (2003,190623);
    Seinfeld et al. (2004, 190388)
    Jacob et al. (2003, 190987)
    Hoell et al. (1 996, 190607: 1 997, 057373)
    Kaufman etal. (1992. 044557)
    Kaufman etal. (1998. 089989)
    Andreae etal. (2004, 155658)
    King et al. (2003, 094395)
    Lindesay etal. (1996,190403)
    Fishman etal. (1996,190566)
    Haywood etal. (2008,190602)
    Heintzenberg et al. (2008, 190605)
    Tanre et al. (2003, 190454)
    Reid etal. (2003, 190213)
    Reid etal. (2008. 190214)
    Bates etal. ((1998. 190063) ;
    Quinn and Coffman (1998.190918)
                                                                                                               Source: Yu (2006,156173)
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    Table 9-6.    Summary of major U.S. surface in situ and remote sensing networks for the
                tropospheric aerosol characterization and radiative forcing research. All the reported
                quantities are column-integrated or column-effective, except as indicated.
    
    In situ
    Remote
    Sensing
    Surface Network
    NOAA ESRL aerosol monitoring
    (http://www.esrl.noaa.gov/amd/aero/)
    NPS/EPA IMPROVE
    (http://vista.cira.colostate.edu/improve/)
    NASAAERONET
    (http ://aeronet.gsfc .nasa .gov)
    DOE ARM (http://www.arm.gov)
    NOAASURFRAD
    (http://www.srrb.noaa.gov/surfrad/)
    AERONET-MAN
    (http ://aeronet.gsfc .nasa .gov/maritime aero
    sol network.html)
    NASAMPLNET
    (http ://mplnet.gsfc .nasa .gov/)
    Measured/Derived Parameters
    Loading
    Near-surface
    extinction
    coefficient,
    optical depth,
    CN/CNN
    number
    concentrations
    Near-surface
    mass
    concentrations
    and derived
    extinction
    coefficients by
    species
    Optical depth
    Vertical profiles
    of backscatter/
    extinction
    coefficient
    Size, Shape
    Angstrom
    exponent,
    hemispheric
    backscatter
    fraction,
    asymmetry
    factor,
    hygroscopic
    growth
    Fine and coarse
    separately
    Fine-mode
    fraction,
    Angstrom
    exponents,
    asymmetry
    factor, phase
    function, non-
    spherical
    fraction
    N/A
    N/A
    Absorption
    Single-
    scattering
    albedo,
    absorption
    coefficient
    Single-scattering
    albedo,
    absorption
    coefficient
    Single-
    scattering
    albedo,
    absorption
    optical depth,
    refractive
    indices
    N/A
    N/A
    Chemistry
    Chemical
    composition in
    selected sites
    and periods
    Ions ammonium
    S04 ,
    ammonium
    nitrate organics,
    EC, fine soil
    N/A
    N/A
    N/A
    Spatial
    Coverage
    5 baseline
    stations,
    several
    regional
    stations,
    aircraft and
    mobile
    platforms
    156NPsand
    wilderness
    areas in the
    U.S.
    -200 sites
    over global
    land and
    islands
    6 sites and 1
    mobile facility
    in N.America,
    Europe, and
    Asia
    7 sites in the
    U.S.
    Global Ocean
    -30 sites in
    major
    continents,
    usually
    co-located
    with
    AERONET
    and ARM sites
    Temporal
    Coverage
    1976 onward
    1988 onward
    1993 onward
    1989 onward
    1995 onward
    2004-present
    periodically
    2000 onward
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    Figure 9-61.    Geographical coverage of active AERONET sites in 2006.
    9.3.2.5.   Ground-Based Remote Sensing Measurement Networks
    
                    The Aerosol Robotic Network (AERONET) program is a federated ground-based remote
                sensing network of well-calibrated sun photometers and radiometers
                dittp://aeronet. gsfc.nasa. gov).
                    AERONET includes about 200 sites around the world,  covering all major tropospheric
                aerosol regimes (Holben et al., 1998, 155848: 2001, 190618), as illustrated in Figure 9-61.
                Spectral measurements of sun and sky radiance are calibrated and screened for cloud-free
                conditions (Smirnov et al., 2000, 190397). AERONET stations provide direct, calibrated
                measurements of spectral AOD (normally at wavelengths of 440, 670, 870, and 1020 nm) with
                an accuracy of ± 0.015 (Eck et al., 1999, 190390). In addition, inversion-based retrievals of a
                variety of effective, column-mean properties have been developed, including aerosol single-
                scattering albedo, size distributions, fine-mode fraction, degree of non-sphericity, phase
                function, and asymmetry factor (Dubovik  and King, 2000,  190197; Dubovik et al., 2000,
                190177: Dubovik et al., 2002, 190202: O'Neill et al., 2003,  180187). The SSA can be retrieved
                with an accuracy of ± 0.03, but only for AOD >0.4 (Dubovik et al., 2002,190202), which
                precludes much of the planet. These retrieved parameters have been validated or are
                undergoing validation by comparison to  in situ measurements (e.g., Haywood et al., 2003,
                190599: Leahy et al., 2007, 190232: Magi et al., 2005, 190468).
                    Recent developments associated with AERONET algorithms and data products include:
                    •    simultaneous retrieval of aerosol and surface properties using combined AERONET
                         and satellite measurements (Sinyuk et al.,  2007, 190395) with surface reflectance
                         taken into account (which significantly improves AERONET SSA retrieval
                         accuracy) (Eck et al., 2008, 190409):
                    •    the addition of ocean color and high frequency solar flux measurements; and
                    •    the establishment of the Maritime Aerosol Network (MAN) component to monitor
                         aerosols over the World oceans from ships of- opportunity (Smirnov et al., 2006,
                         190400).
                    Because of consistent calibration, cloud-screening, and retrieval methods, uniformly
                acquired and processed data are available from all stations,  some of which have operated for
                over 10 years. These data constitute a high-quality, ground-based aerosol climatology and, as
                such, have been widely used for aerosol process studies as well as for evaluation and
                validation of model simulation and satellite remote sensing  applications (e.g., Chin et al.,
                2002, 189996: Kahn et al., 2005, 190966: Remer et al., 2005, 190221: Yu et al., 2003,  156171:
                2006, 156173). In addition, AERONET retrievals of aerosol size distribution and refractive
                indices have been used in algorithm development for satellite sensors (Levy et al., 2007,
                190377: Remer et al., 2005, 190221). A set of aerosol optical properties provided by
                AERONET has been used to calculate the aerosol direct radiative forcing (Procopio et al.,
                2004, 190571: Zhou et al., 2005,  156183), which can be used to  evaluate both satellite remote
                sensing measurements and model simulations.
                    AERONET measurements are complemented by other  ground-based aerosol networks
                having less geographical or temporal coverage, such as the Atmospheric Radiation
                Measurement (ARM) network (Ackerman and Stokes, 2003, 192080), NOAA's national
                surface radiation budget network (SURFRAD) (Augustine et al., 2008, 189913) and other
                networks with multifilter rotating shadowband radiometer (MFRSR) (Harrison et al., 1994,
                045805: Michalsky et al., 2001,190537), and several lidar networks including:
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                     •   NASA Micro Pulse Lidar Network (MPLNET) (Welton et al., 2001, 157133; Welton
                         et al., 2002, 190631);
                     •   Regional East Atmospheric Lidar Mesonet (REALM) in North America (Hoff  and
                         McCann, 2002, 190612; Hoff et al., 2004, 190617);
                     •   European Aerosol Research Lidar Network (EARLINET) (Matthias et al., 2004,
                         155971); and
                         Asian Dust Network (AD-Net) (e.g., Murayama et al., 2001, 155992).
                     Obtaining accurate aerosol extinction profile observations is pivotal to improving aerosol
                 radiative forcing and atmospheric response calculations. The values derived from these lidar
                 networks with state-of-the-art techniques (Schmid et al., 2006, 190372) are helping to fill this
                 need.
    9.3.2.6.    Synergy of Measurements  and Model Simulations
                     Individual approaches discussed above have their own strengths and limitations, and are
                 usually complementary. None of these approaches alone is adequate to characterize large
                 spatial and temporal variations of aerosol physical and chemical properties and to address
                 complex aerosol-climate interactions. The best strategy for characterizing aerosols and
                 estimating their radiative forcing is to integrate measurements from different satellite sensors
                 with complementary capabilities from in situ and surface based measurements. Similarly,
                 while models are essential tools for estimating regional and global distributions and radiative
                 forcing of aerosols at present as well as in the past and the future, observations are required to
                 provide following, several synergistic approaches to studying aerosols and their radiative
                 forcing are discussed.
    
    
           Closure Experiments
    
                     During intensive field studies, multiple platforms and instruments are deployed to sample
                 regional aerosol properties through a well-coordinated experimental design. Often, several
                 independent methods are used to measure or derive a single aerosol property or radiative
                 forcing. This combination of methods can be used to identify inconsistencies in the methods
                 and to quantify uncertainties in measured, derived, and calculated aerosol properties and
                 radiative forcings. This approach, often referred to as a closure experiment, has been widely
                 employed on both individual measurement platforms (local closure) and in studies involving
                 vertical measurements through the atmospheric column by one or more platforms (column
                 closure) (Quinn et al., 1996, 192021;  Russell et al., 1997, 190359).
                     Past closure studies have revealed that the best agreement between methods occurs for
                 submicrometer, spherical particles such that different measures of aerosol optical properties
                 and optical depth agree within 10-15% and often better (e.g., Clarke et al., 1996,  190003;
                 Collins et al., 2000, 190059; Quinn et al., 2004, 190937; Schmid et al., 2000,  190369). Larger
                 particle sizes (e.g., sea salt and dust) present inlet collection efficiency issues and non-
                 spherical particles (e.g., dust) lead to differences in instrumental responses. In these cases,
                 differences between methods for determining aerosol optical depth can be as great as 35%
                 (Doherty et al., 2005, 190027; Wang et al., 2003, 157106). Closure  studies on aerosol clear-sky
                 DRF reveal uncertainties of about 25% for sulfate/carbonaceous aerosol and 60% for dust-
                 containing aerosol (Bates et al., 2006, 189912). Future closure studies could integrate surface-
                 and satellite-based radiometric measurements of AOD with in situ optical, microphysical, and
                 aircraft radiometric  measurements for a wide range of situations. There is also a need to
                 maintain consistency in comparing results and expressing uncertainties (Bates et al., 2006,
                 189912).
    
    
           Constraining Models with In Situ Measurements
    
                     In situ measurements of aerosol chemical, microphysical, and optical properties with
                 known accuracy, based in part on closure studies, can be used to constrain regional CTM
                 simulations of aerosol direct forcing,  as described by Bates et al. (2006, 189912). A key step in
                 the approach is assigning empirically derived optical properties to the individual  chemical
                 components generated by the CTM for use in a Radiative Transfer Model (RTM). Specifically,
                 regional data from focused, short-duration field programs can be segregated according to
                 aerosol type (sea salt, dust, or sulfate/carbonaceous) based on measured chemical composition
                 and particle size. Corresponding measured optical properties can be carried along in the sorting
                 process so that they, too, are segregated by aerosol type. The  empirically derived aerosol
                 properties for individual aerosol types, including mass scattering efficiency, single-scattering
                 albedo, and asymmetry factor, and their dependences on relative humidity, can be used in place
                 of assumed values in CTMs. Short-term, focused measurements of aerosol properties (e.g.,
                 aerosol concentration and AOD) also  can be used to evaluate CTM parameterizations on a
                 regional basis, to suggest improvements to such uncertain model parameters, such as emission
                 factors and scavenging coefficients (e.g., Koch et al., 2007, 190185). Improvements  in these
                 parameterizations using observations  yield increasing confidence in simulations covering
                 regions and periods where and when measurements are not available.  To evaluate the aerosol
    December 2009                                         9-94
    

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                properties generated by CTMs on broader scales in space and time, satellite observations and
                long-term in situ measurements are required.
    
    
           Improved Model Simulations with Satellite Measurements
    
                     Global measurements of aerosols from satellites (mainly AOD) with well-defined
                accuracies offer an opportunity to evaluate model simulations at large spatial and temporal
                scales. The satellite measurements can also be used to constrain aerosol model simulations and
                hence the assessment of aerosol DRF through data assimilation or objective analysis process
                (e.g., Collins et al, 2001, 189987; Liu et al, 2005, 190414; Yu et al, 2003, 156171; 2004,
                190926: 2006, 156173: Zhang et  al., 2008, 190932). Both satellite retrievals and model
                simulations have uncertainties. The goal of data integration is to minimize the discrepancies
                between them, and to form an optimal estimate of aerosol distributions by combining them,
                typically with weights inversely proportional to the square of the errors of individual
                descriptions. Such integration can fill gaps in satellite retrievals and generate global
                distributions of aerosols that are consistent with ground-based measurements (Collins et al.,
                2001,189987; Liu et al., 2005, 190414: Yu et al., 2003, 156171: 2006, 156173). Recent efforts
                have also focused on retrieving global sources of aerosol from satellite observations using
                inverse modeling, which may be valuable for reducing large aerosol simulation uncertainties
                (Dubovik et al., 2007, 190211). Model refinements guided by model evaluation and integration
                practices with satellite retrievals can then be used to improve aerosol simulations of the pre-
                and post-satellite eras. Current measurement-based understanding of aerosol characterization
                and radiative forcing is assessed in Section 9.3.3 through intercomparisons of a variety of
                measurement-based  estimates and model simulations published in literature. This is followed
                by a detailed discussion of major outstanding issues in Section 9.3.4.
                                              • STEM-INDOEX
                                              CD Observation - INDOEX
                                              • STEM - ACE-Asia
                                              cn Observation - ACE-AsiE
                                              • STEM - ICARTT
                                              CD Observation - ICARTT
                                     Sulfate    Ammonium
                                                                POM
                                                                                Sea Salt
                              E  100
                             Ł   10
                             0
                             §
                             o
    •  STEM-INDOEX
    CD  Observation - INDOEX
    •  STEM - ACE-Asia
    CD  Observation - ACE-Asij
    •  STEM - ICARTT
    CD  Observation - ICARTT
                                                                                          Source: Bates etal. (2006,1899121.
    
    Figure 9-62.    Comparison of the mean concentration (ug/m3) and standard deviation of the
                     modeled (STEM) aerosol chemical components with shipboard measurements
                     during INDOEX, ACE-Asia, and ICARTT.
    
           Further complexity is added when attempting to relate surface PM2.5 to aerosol optical depths.
    The main approach to derive surface PM2.5 from satellite optical depths from MISR is based on the
    December 2009
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    use of model derived profiles to determine ratios of aerosol optical depth to surface PM25 (Liu and
    Koutrakis, 2007, 187007; Liu et al, 2007, 098197; Van Donkelaar et al, 2006, 192108).
          Van Donkelaar et al. (2006, 192108) derived r = 0.69 (MODIS) and 0.58 (MISR) with annual
    average ground based PM2.5 across the U.S. and Canada. For comparison, r between AERONET total
    AOD and surface measurements was 0.71. On average, MODIS tended to overestimate surface PM2.5
    by ~5 (ig/m3, while MISR estimates were biased high by about 3 (ig/m3. Liu et al. (2007, 098197)
    and Liu and Koutrakis (2007, 187007) used MISR derived fractional AODs in their analysis and
    found improvement in the retrievals when fractional AODs were used instead of total AOD, allowing
    for better fits to the radiance data. They found that fractional AODs can explain 13-62% of the
    variability in PM2.5 and its components in the eastern U.S. and 28-56% of the variability in the
    western U.S. The models tended to underpredict PM25 by -7-8% in both the East and West. The
    relative errors in surface PM25 were estimated to be  30% in the East and 34% in the West. For AODs
    >0.15 (nominal continental background values), dust particles could be distinguished from other
    particles with an estimated error of 4%. Performance improves substantially over polluted urban
    areas because they have much larger AOD. For example, Gupta et al. (2006, 137694) derived a
    Pearson r between MODIS AOD and surface PM25 of 0.96 for several urban areas around the world.
    The MODIS Aerosol Optical Depth (AOD)/  In-situ PM2 5 correlation summary plot shown in Figure
    9-63 below illustrates the correlation between AOD and surface PM25 across the U.S. and parts of
    Canada. The correlation is based on coincident MODIS AOD pixels and 1-h PM25 concentrations
    from the in-situ continuous surface monitors. The  parameter plotted is the monitoring site-specific
    running correlation coefficient during the preceding  60 days (in color scale). The correlation
    coefficient has values between 1 (perfectly correlated) and -1 (perfectly anti-correlated). A value of
    zero indicates that the two measurements vary independently of each other.
          The running time period of the correlation determination is given in the plot title, 20090704-
    20090901. The size of the point at each site indicates the number of coincidences between MODIS
    AOD pixels and the measured surface 1-h PM25 concentrations for that period. Correlation
    significance generally increases with increasing number of coincidences. Higher correlations suggest
    the MODIS AOD pixel is reflective of in-situ surface PM25 mass concentrations at the monitor
    location.
    December 2009                                 9-96
    

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              20190704-20090901 Correlation between AIRNOW 1 -hour PM2.5 and MODIS AOD
                                                                       ff Coincide ness
                                                                        • 4-
                                                                        • 30-40
                                                                        * 20-30
                                                                        • 10-20
           -1.0
                             -0.5
       0.0
    Correlation
    0.5
    1.0
    Figure 9-63.   Correlations between one-hour PMzs surface measurements in the U.S. and
                 southern Canada reported to AIRNOW and MODIS satellite AOD values for the
                 period between 4 July and 1 September 2009. Symbol size indicates number of
                 coincident points at that location in that period; symbol color is indexed to
                 degree of correlation from -1 (cooler) to +1 (warmer).
    
         The data and image of the aerosol comparison shown in Figure 9-63 were taken from the
    multi-agency project, Infusing satellite Data into Environmental Air Quality Applications (IDEA), a
    partnership of NASA, NOAA, and EPA designed to improve air quality assessment, management,
    and prediction by infusing NASA satellite measurements into NOAA and  EPA analyses for public
    benefit. IDEA is funded by these three  agencies and managed by the University of Maryland
    Baltimore County and NOAA.
    
    
    9.3.3. Assessments of Aerosol Characterization  and Climate Forcing
    
         Sections 9.3.3 through 9.3.6 come directly from CCSP SAP2.3 Chapters 2, Section 2.3
    through Chapter 3, Section 3.8,  with section, table, and figure numbers changed to be internally
    consistent with this ISA.
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                     This section focuses on the assessment of measurement-based aerosol characterization
                 and its use in improving estimates of the direct radiative forcing on regional and global scales.
                 In situ measurements provide highly accurate aerosol chemical, microphysical, and optical
                 properties on a regional basis and for the particular time period of a given field campaign.
                 Remote sensing from satellites and ground-based networks provide spatial and temporal
                 coverage that intensive field campaigns lack. Both in situ measurements and remote sensing
                 have been used to determine key parameters for estimating aerosol direct radiative forcing
                 including aerosol single scattering albedo, asymmetry factor, optical depth remote sensing has
                 also been providing simultaneous measurements of aerosol optical depth and radiative fluxes
                 that can be combined to derive aerosol direct radiative forcing at the TOA with relaxed
                 requirement for characterizing aerosol properties. Progress in using both satellite and surface-
                 based measurements to study  aerosol-cloud interactions and aerosol indirect forcing is also
                 discussed.
    
    
    
    9.3.3.1.    The Use of Measured Aerosol Properties to Improve Models
    
                     The wide variety of aerosol data sets from intensive field campaigns provides a rigorous
                 "testbed" for model simulations of aerosol properties and distributions and estimates of DRF.
                 As described in Section 9.3.2.6, in situ measurements can be used to constrain regional CTM
                 simulations of aerosol properties, DRF, anthropogenic component of DRF, and to evaluate
                 CTM parameterizations. In addition, in situ measurements can be used to develop simplifying
                 parameterizations for use by CTMs.
                     Several factors contribute to the uncertainty of CTM calculations of size-distributed
                 aerosol composition including emissions, aerosol removal by wet deposition, processes
                 involved in the formation of secondary aerosols and the chemical and microphysical evolution
                 of aerosols, vertical transport, and meteorological fields including the timing and amount of
                 precipitation, formation of clouds, and relative humidity. In situ measurements made during
                 focused field campaigns provide a point of comparison for the CTM-generated aerosol
                 distributions at the surface and at discrete points above the surface. Such comparisons are
                 essential for identifying areas where the models need improvement.
    December 2009                                        9-98
    

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       Pittsburgh, PA PSP, NY   Chebogue  Edinburgh UK   Manchester, UK    TORCH 1, UK TORCH 2, UK   Hyytiala     QUEST  Taunus, Germany
                           CAN         " '    (Winter)   (Summer)       '               Finland     Finland          3
                 12 ug/m   2.9 ug/m     3.0 |jg/m    5.2 ug/m   14.0 ug/m   5.3 ug/m     7.6 ug/m     2.0 ug/m     2.6 ug/m     16 ug/m
        »«•   •  • •  •
        7 0 ug/m   >v     \      \          ^v        \          /
       I         N150  \    \00         ^     \        /
         12 ug/m3   13 ug/m3    31 ug/m3   2.8 ug/m3   8.5 ug/m3   1.5 ug/m3   2.3 ug/m3    11 ug/m3    13 ug/m3     13 ug/m
                             *
                 Houston   Mexico City Duke Forest Off Coast NE Mace Head  Jungfraujoch  Cheju Island Okinawa Island Fukue Island
                   TX                NC       US      Ireland   Switzerland     Korea      Japan      Japan
                                                                                Source: Data from Zhang et al. (2007,189998).
    
    
    Figure 9-64.    Location of aerosol chemical composition measurements with aerosol mass
                    spectrometers. Colors for the  labels indicate the type of sampling location:
                    urban areas (blue), <100 mi  downwind of major cites (black), and rural/remote
                    areas >100 miles downwind (pink). Pie charts show the average mass
                    concentration and chemical composition: organics (green), S042~(red), nitrate
                    (blue), ammonium (orange), and chloride (purple), of non-refractory PMi.
    
                    Figure 9-62 shows a comparison of submicrometer and supermicrometer aerosol chemical
                components measured during INDOEX, ACEAsia, and ICARTT onboard a ship and the same
                values calculated with the STEM Model (e.g., Bates et al., 2004, 189958: Carmichael et al.,
                2002, 148319; Carmichael et al., 2003, 190042; Streets et al., 2006, 157019; Tang et al., 2003,
                190441: Tang et al., 2004, 190445). To permit direct comparison of the measured and modeled
                values, the model was driven by analyzed meteorological data and sampled at the times and
                locations of the shipboard measurements every 30 min along the cruise track. The best
                agreement was found for submicrometer sulfate and BC. The agreement was best for sulfate;
                this is attributed to greater accuracy in emissions, chemical conversion, and removal for this
                component. Underestimation of dust and sea salt is most likely due to errors in model-
                calculated emissions. Large discrepancies between the modeled and measured values occurred
                for submicrometer particulate organic matter (POM) (INDOEX), and for particles in the
                supermicrometer size range such as dust (ACE-Asia), and sea salt (all regions). The model
                underestimated the total mass of the supermicrometer aerosol by about a factor of 3. POM
                makes up a large and variable fraction of aerosol mass throughout the anthropogenically
                influenced northern hemisphere, and yet models have severe problems in properly representing
                this type of aerosol. Much of this discrepancy follows from the models inability to represent
                the formation of secondary organic aerosols (SOA) from the precursor volatile organic
                compounds (VOC). Figure 9-64 shows a summary of the results from aerosol mass
                spectrometer measurements at 30 sites over North America, Europe, and Asia. Based on
                aircraft measurements of urban-influenced air over New England, de Gouw et al. (2005,
                190020) found that POM was highly correlated with secondary anthropogenic gas phase
                species suggesting that the POM was derived from secondary anthropogenic sources and that
                the formation took one day or more.
    December 2009
    9-99
    

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                    25-
                 120-
    O  la '
    CL
    
    I 10-
    J3
    13
    
    W  5-
                     0-
                                    0    10   20   30
                                   Photochemical age (h)
                                       I        I
                       0.0      0.5     1.0     1.5
                                Acetylene (ppbv)
                                                                  J	I
                                                           O
                                                           CL
    25-
    
    
    20-
    
    
    
    
    
    10-
    
    
     5-
    
    
     0-
                                                             I        i       l
                                                             10     20      30
                                                           Iso-propyl nitrate (pptv)
                                                                                 Source: Data from de Guowet al. (2005,190020).
    Figure 9-65.   Scatterplots of the submicrometer POM measured during NEAQS versus
                    A) acetylene and B) iso-propyl nitrate.  The colors of the data points in A) denote
                    the  photochemical age as determined by the ratios of compounds of known OH
                    reactivity. The gray area in A) shows the range of ratios between  submicrometer
                    POM and acetylene observed by Kirchstetter et al. (1999, 010642) in tunnel
                    studies.
    
                    Figure 9-65 shows scatterplots of submicrometer POM versus acetylene (a gas phase
                primary emitted VOC species) and isopropyl nitrate (a secondary gas phase organic species
                formed by atmospheric reactions). The increase in submicrometer POM with increasing
                photochemical age could not be explained by the removal of VOC alone, which are its
                traditionally recognized precursors. This result suggests that other species must have
                contributed and/or that the mechanism for POM formation is more efficient than assumed by
                models. Similar results were obtained from the 2006 MILAGRO field campaign conducted in
                Mexico City (Kleinman et al., 2008, 190074X and comparisons of GCM results with several
                long-term monitoring stations also showed that the model underestimated organic aerosol
                concentrations (Koch et al., 2007, 190185). Recent laboratory work suggests that isoprene may
                be a major SOA source missing from previous atmospheric models (Henze and Seinfeld,
                2006, 190606: Kroll et al., 2006,  190195X but underestimating sources from certain economic
                sectors may also play a role (Koch et al., 2007, 190185). Models also have difficulty in
                representing the vertical distribution of organic aerosols, underpredicting their occurrence in
                the free troposphere (FT) (Heald et al., 2005, 190603). While organic aerosol presents models
                with some of their greatest challenges, even the distribution of well-characterized sulfate
                aerosol is not always estimated correctly in models (Shindell et al., 2008, 190391).
                    Comparisons of DRF and its anthropogenic component calculated with assumed optical
                properties and values constrained by in situ measurements can help identify areas of
                uncertainty in model parameterizations. In a study described by Bates et al. (2006, 189912X
                two different CTMs (MOZART and STEM) were used to  calculate dry mass concentrations of
                the dominant aerosol species (sulfate, organic carbon, BC, sea salt, and dust).
                    In situ measurements were used to calculate the corresponding optical properties for each
                aerosol type for use in a radiative transfer model. Aerosol DRF and its anthropogenic
                component estimated using the empirically derived and a priori optical properties were then
                compared. The DRF and its anthropogenic component were calculated as the net downward
                solar flux difference between the model state with aerosol and of the model state with no
                aerosol. It was found that the constrained optical properties derived from measurements
                increased the calculated AOD (34 ± 8%), TOADRF (32 ± 12%), and anthropogenic
                component of TOADRF (37 ± 7%) relative to runs using the a priori values. These increases
                were due to larger values of the constrained mass  extinction efficiencies relative to the a priori
                values. In addition,  differences in AOD due to using the aerosol loadings from MOZART
                versus those from STEM were much greater than  differences resulting from the a priori vs.
                constrained RTM runs. In situ observations also can be used to generate simplified
                parameterizations for CTMs and RTMs thereby lending an empirical foundation to uncertain
                parameters currently in use by models. CTMs generate concentration fields of individual
                aerosol chemical components that are then used as input to radiative transfer models (RTMs)
                for the calculation of DRF. Currently,  these calculations are performed with a variety of
                simplifying assumptions concerning the RH dependence of light scattering by the aerosol.
    December 2009
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                 Chemical components often are treated as externally mixed each with a unique RH
                 dependence of light scattering. However, both model and measurement studies reveal that
                 POM, internally mixed with water-soluble salts, can reduce the hygroscopic response of the
                 aerosol, which decreases its water content and ability to scatter light at elevated relative
                 humidity (e.g., Carrico et al, 2005, 190052; Saxena et al, 1995, 077273).
                     The complexity of the POM composition and its impact on aerosol optical properties
                 requires the development of simplifying parameterizations that allow for the incorporation of
                 information derived from field measurements into calculations of DRF (Quinn et al., 2005,
                 156033). Measurements made during INDOEX, ACE-Asia, and ICARTT revealed a
                 substantial decrease in fasp(RH) with increasing mass fraction of POM in the accumulation
                 mode. Based on these data, a parameterization was developed that quantitatively describes the
                 relationship between POM mass fraction and fasp(RH) for accumulation mode sulfate-POM
                 mixtures (Quinn et al., 2005, 156033). This simplified parameterization may be used as input
                 to RTMs to derive values of fasp(RH) based on CTM estimates of the POM mass fraction.
                 Alternatively, the relationship may be used to assess values of fasp(RH) currently being used
                 in RTMs.
    
    
    
    9.3.3.2.    Intercomparisons of Satellite  Measurements and Model Simulation of Aerosol
    
    Optical  Depth
    
                     As aerosol DRF is highly dependent on the amount of aerosol present, it is of first-order
                 importance to improve the spatial characterization of AOD on a global scale. This requires an
                 evaluation of the various remote sensing AOD data sets and comparison with model-based
                 AOD estimates. The latter comparison is particularly important if models are to be used in
                 projections of future climate states that would result from  assumed future emissions. Both
                 remote sensing and model simulation have uncertainties and satellite-model integration is
                 needed to obtain an optimum description of aerosol distribution.
                     Figure 9-65 shows an intercomparison of annual average AOD at 550 nm from two recent
                 satellite aerosol sensors (MODIS and MISR), five model simulations (GOCART, GISS,
                 SPRINTARS, LMDZ-LOA, LMDZ-INCA) and three satellite-model integrations (MO_GO,
                 MI_GO, MO_MI_GO). These model-satellite integrations are conducted by using an optimum
                 interpolation approach (Yu et al.,  2003, 156171) to constrain GOCART simulated AOD with
                 that from MODIS, MISR, or MODIS over ocean and MISR over land, denoted as MO_GO,
                 MI_GO, and MO_MI_GO, respectively. MODIS values of AOD are from Terra Collection 4
                 retrievals and MISR AOD is based on early post launch retrievals. MODIS and MISR
                 retrievals give a comparable average AOD on the global scale, with MISR greater than
                 MODIS by 0.01-0.02 depending  on the  season. However, differences between MODIS and
                 MISR are much larger when land and ocean are examined separately: AOD from MODIS is
                 0.02-0.07 higher over land but 0.03-0.04 lower over ocean than the AOD from MISR.  Several
                 major causes for the systematic MODIS-MISR differences have been identified, including
                 instrument calibration and sampling differences, different  assumptions about ocean surface
                 boundary conditions made in the  individual retrieval algorithms, missing particle property or
                 mixture options in the look-up tables, and cloud screening (Kahn et al., 2007, 190963). The
                 MODIS-MISR AOD differences are being reduced by continuous efforts on improving
                 satellite retrieval algorithms and radiance calibration. The new MODIS aerosol retrieval
                 algorithms in Collection 5 have resulted in a reduction of 0.07  for global land mean AOD
                 (Levy et al., 2007, 190379), and improved radiance calibration for MISR removed —40% of
                 AOD bias over dark water scenes (Kahn et al., 2005, 190965).
                     The annual and global average AOD from the five models is 0.19 ± 0.02 (mean ± standard
                 deviation) over land and 0.13 ± 0.05 over ocean, respectively. Clearly, the model-based mean
                 AOD is smaller than both MODIS- and MISR-derived values (except the GISS model). A
                 similar conclusion has been drawn from more extensive comparisons involving more models
                 and satellites (Kinne et al., 2006,  155903). On regional scales,  satellite-model differences are
                 much larger. These differences could be  attributed in part to cloud contamination (Kaufman et
                 al., 2005, 155891; Zhang et al., 2005, 190931) and 3D cloud effects in satellite retrievals
                 (Kaufman et al., 2005, 155891: Wen et al., 2006, 179964) or to models missing  important
                 aerosol sources/sinks or physical  processes (Koren et al., 2007, 190192). Integrated satellite-
                 model products are generally in-between the satellite retrievals and the model simulations, and
                 agree better with AERONET measurements (e.g., Yu et al., 2003, 156171). As in comparisons
                 between models and in situ measurements (Bates et al., 2006, 189912), there appears to be a
                 relationship between uncertainties in the representation of dust in models and the uncertainty
                 in AOD, and its global distribution.
     For example, the GISS model generates more dust than the other models (Figure 9-67), resulting in a closer agreement with MODIS and MISR in the global mean (Source: Data
                                                                                          taken from Kinne et al. (2006,155903)
                     Figure 9-66). However, the distribution of AOD between land and ocean is quite different
                 from MODIS- and MISR-derived values.
                     Figure 9-67 shows larger model differences in the simulated percentage contributions of
                 individual components to the total aerosol optical depth on a global scale, and hence in the
                 simulated aerosol single-scattering properties (e.g., single-scattering albedo, and phase
                 function), as  documented in Kinne et al. (2006, 155903). This, combined with the differences
    December 2009                                        9-101
    

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                in aerosol loading (as characterized by AOD) determines the model diversity in simulated
                aerosol direct radiative forcing, as discussed later. However, current satellite remote sensing
                capability is not sufficient to constrain model simulations of aerosol components.
                                                                • Und BOcean • Global
                                           ^    rf    0°°    JP     &*           ^
                                                                             Source: Data taken from Kinne et al. (2006,1559031
    
    
    Figure 9-66.    Comparison of annual mean aerosol optical depth (AOD).
                       100%
    
                        80%
    
                        60%
                        am
    •      •      •      •
    
    
                                   • ss
                                    DU
                                    POM
                                   • BC
                                    SU
                             .^     X
                                                                            Source: Data taken from Kinne et al. (2006,1559031.
    Figure 9-67.    Percentage contributions of individual aerosol components.  SU - sulfate, BC -
                    BC, POM - particulate organic matter, DU - dust, SS - sea salt; to the total
                    aerosol optical depth (at 550 nm) on a global scale simulated by the five models.
    9.3.3.3.   Satellite-Based Estimates of Aerosol Direct Radiative Forcing
    
                    Table 9-7 summarizes approaches to estimating the aerosol direct radiative forcing,
                including a brief description of methods, identifies major sources of uncertainty, and provides
                references. These estimates fall into three broad categories, namely (A) satellite-based, (B)
                satellite-model integrated, and (C) model-based. As satellite aerosol measurements are
                generally limited to cloud-free conditions, the discussion here focuses on assessments of clear-
                sky aerosol direct radiative forcing, a net (downwelling minus upwelling) solar flux difference
                between with aerosol (natural + anthropogenic) and in the absence of aerosol.
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           Global Distributions
    
                     Figure 9-68 shows global distributions of aerosol optical depth at 550 nm (left panel) and
                 diurnally averaged clear-sky TOA DRF (right panel) for March-April-May (MAM) based on
                 the different approaches. The DRF at the surface follows the same pattern as that at the TOA
                 but is significantly larger in magnitude because of aerosol absorption. It appears that different
                 approaches agree on large-scale patterns of aerosol optical depth and the direct radiative
                 forcing. In this season, the aerosol impacts in the Northern Hemisphere are much larger than
                 those in the Southern Hemisphere. Dust outbreaks and biomass burning elevate the optical
                 depth to more than 0.3 over large parts of North Africa and the tropical Atlantic. In the tropical
                 Atlantic, TOA cooling as large as -10 W/m2 extends westward to Central America. In eastern
                 China, the optical  depth is as high as 0.6-0.8, resulting from the combined effects of industrial
                 activities and biomass burning in the south, and dust outbreaks in the north. The Asian impacts
                 also extend to the North Pacific, producing a TOA cooling of more than -10 W/m . Other areas
                 having large aerosol impacts include Western Europe, midlatitude North Atlantic, and much of
                 South Asia and the Indian Ocean. Over the "roaring forties" in the Southern Hemisphere, high
                 winds generate a large amount of sea salt. Elevated optical depth, along with high solar zenith
                 angle and hence large backscattering to space, results in a band of TOA cooling of more than -
                 4 W/m2. However, there  is also some question as to whether thin cirrus (e.g., Zhang et al,
                 2005, 190931) and unaccounted-for whitecaps contribute to the apparent enhancement in AOD
                 retrieved by satellite. Some differences exist between different approaches. For example, the
                 early post-launch MISR retrieved optical depths over the southern hemisphere oceans are
                 higher than MODIS retrievals and GOCART simulations. Over the "roaring forties," the
                 MODIS derived TOA solar flux perturbations are larger than the  estimates from other
                 approaches.
    December 2009                                        9-103
    

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    Table 9-7.     Summary of approaches to estimating the aerosol direct radiative forcing  in three
                     categories:  (1) satellite retrievals; (2) satellite-model integrations; and (3) model
                     simulations.
      Category     Product
                        Brief Description
                                            Identified Sources of Uncertainty
                                                         Major References
                 MODIS
                Using MODIS retrievals of a linked
                set of AOD, u0, and phase function
                consistently in conjunction with a
                radiative transfer model (RTM) to
                calculate TOA fluxes that best match
                the observed radiances.
                                     Radiance calibration, cloud-aerosol discrimination,
                                     instantaneous-to-diurnal scaling, RTM
                                     parameterizations
                                                    Remer and Kaufman (2006,
                                                    190222)
                 MODIS A
                Splitting MODIS AOD over ocean into
                mineral dust, sea salt, and biomass-
                burning and pollution; using AERONET
                measurements to derive the size
                distribution and single-scattering albedo ^ngieAERONET site'tocharacte'rFe a large r^Jion
                for individual components.
                                     Satellite AOD and FMF retrievals, overestimate due to
                                     summing up the compositional direct forcing, use of a
                                                                                                            Bellouin et al. (2005,1556841
    A Satellite
    retrievals
                 CERES A
                Using CERES fluxes in combination
                with standard MODIS aerosol.
                             Using CERES fluxes in combination
                 CERES_B   with NOAA NESDIS aerosol from
                             MODIS radiances.
                             Using CERES fluxes in combination
                 „___- „   with MODIS (ocean) and MISR (non-
                       -     desert land) aerosol with new angular
                             models for aerosols.
                                                Calibration of CERES radiances, large CERES
                                                footprint, satellite AOD retrieval, radiance-to-flux
                                                conversion (ADM), instantaneous-to-diurnal scaling,
                                                narrow-to-broadband conversion
                                                                                               Loeb and Manalo-Smith
                                                                                               (2005,190433); Loeb and
                                                                                               Kato (2002,190432)
                                                                                    Zhang etal. (2005, 086743;
                                                                                    2005,157185); Zhang and
                                                                                    Christopher (2003,190928);
                                                                                    Christopher etal. (2006,
                                                                                    155729); Patadiaetal. (2008,
                                                                                    190558)
                             Using POLDER AOD in combination
                 POLDER    with prescribed aerosol models
                             (similar to MODIS).
                                                Similar to MODIS
                                                                                    Boucher and Tanre (2000,
                                                                                    190041): Bellouin etal.
                                                                                    (2003.189911)
                 MODIS_G
    
                 MISR  G
                Using GOCART simulations to fill
                AOD gaps in satellite retrievals.
    B. Satellite-
    model
    integrations
                 MO GO
                Integration of MODIS and GOCART
                AOD.
                Integration of GOCART AOD with
    MO_MI_GO  retrievals from MODIS (Ocean) and
                MISR (Land).
                                   - Propagation of uncertainties associated with both
                                     satellite retrievals and model simulations (but the
                                     model-satellite integration approach does result in
                                   - improved AOD quality for MO_GO, and 0_MI_GO)
                                                    'Aerosol single-scattering
                                                    albedo and asymmetry factor
                                                    are taken from GOCART
                                                    simulations
    
                                                    *Yuetal. (2003.156171:
                                                    2004.190926:2006.156173)
                 SeaWiFS
                Using SeaWiFS AOD and assumed
                aerosol models.
                                     Similar to MODIS_G and MISR_G, too weak aerosol
                                     absorption
                                                                                                            Chou et al. (2002,190008)
                 GOCART
                Offline RT calculations using
                monthly avg aerosols with a time step
                of 30 min (without the presence of
                clouds).
                 CDDIMTADC  Online RT calculations every 3 hrs
                 SPRINTARS
    C. Model
    simulations
    GISS
    Online model simulations and
    weighted by clear-sky fraction.
     Emissions, parameterizations of a variety of sub-grid
    " aerosol processes (e.g., wet and dry deposition, cloud
     convection, aqueous-phase oxidation), assumptions on
     aerosol size, absorption, mixture, and humidification of
    . particles, Meteorology fields, not fully evaluated
     surface albedo schemes, RT parameterizations
                 LMDZ-INCA
                Online RT calculations every 2 hrs
                (cloud fraction = 0).
                 LMDZ-LOA
                Online RT calculations every 2 hrs
                (cloud fraction = 0).
                                                                                    Chin etal. (2002,189996) ;Yu
                                                                                    etal. (2004,190926)
    Takemura et al. (2002,
    190438:2005.190439)
    
    Koch and Hansen (2005,
    190183): Koch etal. (2006.
    190184)
                                                                                    Balkanskietal. (2007,
                                                                                    189979);Schulzetal. (2006,
                                                                                    190381): Kinne etal. (2006.
                                                                                    155903)
                                                                                    Reddy et al. (2005,190207:
                                                                                    2005.190208)
                                                                                                   Source: Adapted from Yu et al. (2006,1561731.
    December 2009
                                                     9-104
    

    -------
                       MODIS
                   MODIS
                     MO Ml  GO
                      GOCART
                                                           CERES A
                 MO MI_GO
                                                           •.
           .0  ,05 ,1  .15 .2  ,3  .4  .5  .6 .8  I. -30 -20 -15 -10  -8  -6  -4  -2  0  5Wms
    
                                                                          Source: Yu et al. (2006,156173)
    
    Figure 9-68.   Geographical patterns of seasonally (MAM) averaged aerosol optical depth at 550
                 nm (left panel) and the diurnally averaged clear-sky aerosol direct radiative (solar
                 spectrum) forcing (W/m2) at the TOA (right panel) derived from satellite (Terra)
                 retrievals. MODIS (Remer and Kaufman, 2006,190222; Remeret al., 2005,
                 190221): MISR (Kahn et al., 2005,190966): and CERES_A (Loeb and Manalo-
                 Smith, 2005,190433): GOCART simulations (Chin et al., 2002,189996: Yu et al.,
                 2004,190926): and GOCART-MODIS-MISR integrations (MO_MI_GO) (Yu et al.,
                 2006.156173).
    December 2009
    9-105
    

    -------
           Global Mean
                    Figure 9-69 summarizes the measurement- and model-based estimates of clear-sky
                annual-averaged DRF at both the TOA and surface from 60°S to 60°N. Seasonal DRF values
                for individual estimates are summarized in Table 9-8 and Table 9-9 for ocean and land,
                respectively. Mean, median and standard error e (s=a/(n-1)1/2), where a is standard deviation
                and n is the number of methods) are calculated for measurement- and model-based estimates
                separately. Note that although the standard deviation or standard error reported here is not a
                fully rigorous measure of a true experimental uncertainty, it is indicative of the uncertainty
                because independent approaches with independent sources of errors are used (see Table 9-7; in
                the modeling community, this is called the "diversity;" see Section 9.3.6).
           Ocean
                    For the TOA DRF, a majority of measurement-based and satellite-model integration-based
                estimates agree with each other within about 10%. On annual average, the measurement-based
                estimates give the DRF of -5.5 ± 0.2 W/m2 (mean ± e) at the TOA and -8.7 ± 0.7 W/m2 at the
                surface. This suggests that the ocean surface cooling is about 60% larger than the cooling at
                the TOA. Model simulations give wide ranges of DRF estimates at both the TOA and surface.
                The ensemble of five models gives the annual average DRF (mean± e) of-3.2 ± 0.6 W/m2 and
                -4.9 ±0.8 W/m2 at the TOA and surface, respectively. On average, the surface cooling is about
                37% larger than the TOA cooling, smaller than the measurement-based estimate of surface and
                TOA difference of 60%. However, the 'measurement-based' estimate of surface DRF is
                actually a calculated value, using poorly constrained particle properties.
          Land
                    It remains challenging to use satellite measurements alone for characterizing complex
                aerosol properties over land surfaces with high accuracy. As such, DRF estimates over land
                have to rely largely on model simulations and satellite-model integrations. On a global and
                annual average, the satellite-model integrated approaches derive a mean DRF of-4.9 W/m2 at
                the TOA and -11.9 W/m at the surface respectively. The surface cooling is more than a factor
                of 2 larger than the TOA cooling because of aerosol absorption. Note that the TOA DRF of -
                4.9 W/m2 agrees quite well with the most recent satellite-based estimate of -5.1 ± 1.1 W/m2
                over non-desert land based on coincident measurements of MISR AOD and CERES solar flux
                (Patadia et al., 2008, 190558). For comparisons, an ensemble of five model simulations
                derives a DRF (mean ± e) over land of-3.0 ± 0.6 W/m2 at the TOA and -7.6 ± 0.9 W/m2 at the
                surface, respectively. Seasonal variations of DRF over land, as derived from both
                measurements and models, are larger than those over ocean.
    aaa
                  0
                            DOBS
                                             MOD
                                                             -15
                                                             -12
                                                                         DOBS
                                                                                           MOD
                                                              -3
    
    
                                                              0
                          OCEAN
                                             LAND
                                                                       OCEAN
                                                                                           LAND
    
                                                                                           Source: Yu et al. (2006,156173)
    Figure 9-69.   Summary of observation- and model-based (denoted as OBS and MOD,
                    respectively) estimates of clear-sky, annual average DRF  at the TOA and at the
                    surface.  The box and vertical bar represent median and standard error,
                    respectively.
    December 2009
    9-106
    

    -------
    Table 9-8.
    Summary of seasonal and annual average clear-sky DRF (W/m2)  at the TOA and the
    surface (SFC) over global OCEAN derived with different methods and data.
                                      DJF
                                         MAM
    JJA
    SON
    ANN
    
    MODIS
    MODIX_A*
    CERES_A
    CERES_B
    CERES_C
    MODIS_G
    MISR_G**
    MO_GO
    MO_MI_GO
    POLDER
    SeaWiFS
    Obs. Mean
    Obs. Median
    Obs.o
    Obs.t
    GOCART
    SPRINTARS
    GISS
    LMDZ-INCA
    LMDZ-LOA
    Mod. Mean
    Mod Median
    Mod.o
    Mod.t
    Mod ./Obs.
    TOA
    -5.9
    -6.0
    -5.3
    -3.8
    -5.3
    -5.5
    -6.4
    -4.9
    -4.9
    -5.7
    -6.0
    -5.4
    -5.5
    0.72
    0.23
    -3.6
    -1.5
    -3.3
    -4.6
    -2.2
    -3.0
    -3.3
    1.21
    0.61
    .60
    SFC
    
    -8.2
    
    
    
    -9.1
    -10.3
    -7.8
    -7.9
    
    -6.6
    -8.3
    -8.1
    1.26
    0.56
    -5.7
    -2.5
    -4.1
    -5.6
    -4.1
    -4.4
    -41.
    1.32
    0.66
    .51
    TOA
    -5.8
    -6.4
    -6.1
    -4.3
    -5.4
    -5.7
    -6.5
    -5.1
    -5.1
    -5.7
    -5.2
    -5.6
    -5.7
    0.64
    0.20
    -4.0
    -1.5
    -3.5
    -4.7
    -2.2
    -3.2
    -3.5
    1.31
    0.66
    .61
    SFC
    
    -8.9
    
    
    
    -10.4
    -11.4
    -9.3
    -9.2
    
    -5.8
    -9.2
    -9.3
    1.89
    0.85
    -7.2
    -2.5
    -4.6
    -5.9
    -3.7
    -4.8
    -4.6
    1.84
    0.92
    .50
    TOA
    -6.0
    -6.5
    -5.4
    -3.5
    -5.2
    -6.0
    -7.0
    -5.4
    -5.5
    -5.8
    -4.9
    -5.6
    -5.5
    0.91
    0.29
    -4.7
    -1.9
    -3.5
    -5.0
    -2.5
    -3.5
    -3.5
    1.35
    0.67
    .64
    SFC
    
    -9.3
    
    
    
    -10.6
    -11.9
    -9.4
    -9.5
    
    -5.6
    -9.4
    -9.5
    2.10
    0.94
    -8.0
    -3.3
    -4.9
    -6.3
    -4.4
    -5.4
    -4.9
    1.82
    0.91
    .52
    TOA
    -5.8
    -6.4
    -5.1
    -3.6
    
    -5.5
    -6.3
    -5.0
    -5.0
    -5.6
    -5.3
    -5.4
    -5.4
    0.79
    0.26
    -4.0
    -1.5
    -3.8
    -4.8
    -2.2
    -3.3
    -3.8
    1.36
    0.68
    .70
    SFC
    
    -8.9
    
    
    
    -9.8
    -10.9
    -8.7
    -8.6
    
    -5.7
    -8.8
    -8.8
    1.74
    0.78
    -6.8
    -2.5
    -5.4
    -5.5
    -4.1
    -4.9
    -5.4
    1.63
    0.81
    .61
    TOA
    -5.9
    -6.4
    -5.5
    -3.8
    -5.3
    -5.7
    -6.5
    -5.1
    -5.1
    -5.7
    -5.2***
    -5.4
    -5.5
    -5.5
    0.70
    0.21
    -4.1
    -1.6
    -3.5
    -4.7
    -2.3
    -3.2
    -3.5
    1.28
    0.64
    .64
    SFC
    
    -8.9
    
    
    
    -10.0
    -11.1
    -8.8
    -8.7
    -7.7***
    -5.9
    -8.7
    -8.8
    1.65
    0.67
    -6.9
    -2.7
    -4.8
    -5.8
    -4.1
    -4.9
    -4.8
    1.60
    0.80
    .55
    * High bias may result from adding the DRF of individual components to derive the total DRF (Bellouin et al., 2005,1556841.
    **High bias most likely results from an overall overestimate of 20% in early post-launch MISR optical depth retrievals (Kahn et al., 2005,190966).
    *** Bellouin et al. (2003,1899111 use AERONET retrieval of aerosol absorption as a constraint to the method in Boucher and Tanre (2000,1900411, deriving aerosol direct radiative forcing both at the TOA and
    the surface.
    
    Sources of data: MODIS (Remer & Kaufman, 2006), MODIS_A (Bellouin et al., 2005,1556841. POLDER (Bellouin et al., 2003,189911: Boucher and Tanre, 2000,1900411. CERES_A and CERES_B (Loeb
    and Manalo-Smith, 2005, 1904331. CERES_C (Zhang et al., 2005, 1909301. MODIS_G, MISR_G, MO_GO, MO_MI_GO (Yu et al, 2004,190926: 2006, 1561731. SeaWFS (Chou et al, 2002, 1900081.
    GOCART (Chin et al, 2002,189996: Yu et al, 2004,1909261. SPRINTARS (Takemura et al, 2002,1904381. GISS (Koch and Hansen, 2005,190183: Koch et al, 2006,1901841. LMDZ-INCA (Kinne et al,
    2006,155903: Schulz et al, 2006,1903811. LMDZ-LOA (Reddy et al, 2005,190207: Reddy et al, 2005,1902081. Mean, median, standard deviation (o), and standard error (E) are calculated for observations
    (Obs) and  model simulations (Mod) separately. The last row is the ratio of model median to observational median (taken from Yu et al, 2006,156173).
    December 2009
                                                      9-107
    

    -------
    Table 9-9.     Summary of seasonal and annual average clear-sky DRF (W/m2) at the TOA and the
                   surface (SFC) over global LAND derived with different methods and data.
    
    
                               DJF                MAM               JJA                SON               ANN
          Products      ^^^^^^^^^^^^^^^^^^^^^^^^—^^^^^^^^^^^^^^^^^^^^^^^^—
                          TOA      SFC      TOA     SFC      TOA      SFC      TOA      SFC      TOA      SFC
    MODIS_G
    MISR_G
    MO_GO
    MO_MI_GO
    Obs. Mean
    Obs. Median
    Obs.o
    Obs.t
    GOCART
    SPRINTARS
    GISS
    LMDZ-INCA
    LMDZ-LOA
    Mod. Mean
    Mod Median
    Mod.o
    Mod. Ł
    Mod ./Obs.
    -4.1
    -3.9
    -3.5
    -3.4
    -3.7
    -3.7
    0.33
    0.17
    02.9
    -1.4
    -1.6
    -3.0
    -1.3
    -2.0
    -1.6
    0.84
    0.42
    0.43
    -9.1
    -8.7
    -7.5
    -7.4
    -8.2
    -8.1
    0.85
    0.49
    -6.1
    -4.0
    -3.9
    -5.8
    -5.4
    -5.0
    -5.4
    1.03
    0.51
    0.67
    -5.8
    -5.1
    -5.1
    -4.7
    -5.2
    -5.1
    0.46
    0.26
    -4.4
    -1.5
    -3.2
    -4.0
    -1.8
    -3.0
    -3.2
    1.29
    0.65
    0.63
    -14.9
    -13.0
    -12.9
    -11.8
    -13.2
    -13.0
    1.29
    0.74
    -10.9
    -4.6
    -7.9
    -9.2
    -6.4
    -7.8
    -7.9
    2.44
    1.22
    0.61
    -6.6
    -5.8
    -5.8
    -5.3
    -5.9
    -5.8
    0.54
    0.31
    -4.8
    -2.0
    -3.6
    -6.0
    -2.7
    -3.8
    -3.6
    1.61
    0.80
    0.62
    -17.4
    -14.6
    -14.9
    -13.5
    -15.1
    -14.8
    1.65
    0.85
    -12.3
    -6.7
    -9.3
    -13.5
    -8.9
    -10.1
    -9.3
    2.74
    1.37
    0.62
    -5.4
    -4.6
    -4.8
    -4.3
    -4.8
    -4.7
    0.46
    0.27
    -4.3
    -1.7
    -2.5
    -4.3
    -2.1
    -3.0
    -2.5
    1.24
    0.62
    0.53
    -12.8
    -101.7
    -10.9
    -9.7
    -11.0
    -10.8
    1.29
    0.75
    -9.3
    -5.2
    -6.6
    -8.2
    -6.7
    -7.2
    -6.7
    1.58
    0.79
    0.62
    -5.5
    -4.9
    -4.8
    -4.4
    -4.9
    -4.9
    0.45
    0.26
    -4.1
    -1.7
    -2.8
    -4.3
    -2.0
    -3.0
    -2.8
    1.19
    0.59
    0.58
    -13.5
    -11.8
    -11.6
    -10.6
    -11.9
    -11.7
    1.20
    0.70
    -9.7
    -5.1
    -7.2
    -9.2
    -6.9
    -7.6
    -7.2
    1.86
    0.93
    0.62
    Sources of data: MODIS_G, MISR_G, MO_GO, MO_MI_GO (Yu et al, 2004,190926: 2006, 156173), GOCART (Chin et al, 2002, 189996: Yu et al, 2004, 190926),
    SPRINTARS (Takemura et al, 2002,190438), GISS (Koch and Hansen, 2005,190183: Koch et al, 2006,190184), LMDZ-INCA (Balkanski et al, 2007,189979: Kinne et al,
    2006,155903: Schulz et al, 2006,190381), LMDZ-LOA (Reddy et al, 2005,190207: Reddy et al, 2005,190208). Mean, median, standard deviation (a), and standard error (E)
    are calculated for observations (Obs) and model simulations (Mod) separately. The last row is the ratio of model median to observational median. (Taken from Yu et al, 2006,
    156173).
    
    
                      The above analyses show that, on a global average, the measurement-based estimates of
                 DRF are 55-80% greater than the model-based estimates. The differences are even larger on
                 regional scales. Such measurement-model differences are a combination of differences in
                 aerosol amount (optical depth), single-scattering properties, surface albedo, and radiative
                 transfer schemes (Yu et al., 2006, 156173). As discussed earlier, MODIS retrieved optical
                 depths tend to be overestimated by about 10-15% due to the contamination of thin cirrus and
                 clouds in general (Kaufman et al., 2005, 155891). Such overestimation of optical depth would
                 result in a comparable overestimate of the aerosol direct radiative forcing. Other satellite AOD
                 data may have similar contamination, which however has not yet been quantified. On the other
                 hand, the observations may be measuring enhanced AOD and DRF due to processes not well
                 represented in the models including humidification and enhancement of aerosols in the vicinity
                 of clouds (Koren et al., 2007, 190192).
                      From the perspective  of model simulations, uncertainties associated with
                 parameterizations of various aerosol processes  and meteorological fields, as documented under
                 the AEROCOM and Global Modeling Initiative (GMI) frameworks (Kinne et al., 2006,
                 155903: Liu et al., 2007, 190427: Textor et al., 2006,190456), contribute to the large
                 measurement-model and model-model discrepancies. Factors determining the AOD should be
                 major reasons for the DRF discrepancy and the constraint of model AOD with well evaluated
                 and bias reduced satellite AOD through a data assimilation approach can reduce the DRF
                 discrepancy significantly. Other factors (such as model parameterization of surface reflectance,
                 and model-satellite differences in single-scattering albedo and asymmetry factor due to
                 satellite sampling bias toward cloud-free conditions) should also contribute, as evidenced by
                 the existence of a large discrepancy in the radiative efficiency (Yu et al., 2006, 156173).
                 Significant effort will be needed in the future to conduct comprehensive assessments.
    December 2009                                         9-108
    

    -------
    9.3.3.4.   Satellite-Based Estimates of Anthropogenic Component of Aerosol Direct
    
    Radiative Forcing
    
                     Satellite instruments do not measure the aerosol chemical composition needed to
                discriminate anthropogenic from natural aerosol components. Because anthropogenic aerosols
                are predominantly sub-micron, the fine-mode fraction derived from POLDER, MODIS, or
                MISR might be used as a tool for deriving anthropogenic aerosol optical depth. This could
                provide a feasible way to conduct measurement-based estimates of anthropogenic component
                of aerosol direct radiative forcing (Kaufman et al., 2002, 190956). Such method derives
                anthropogenic AOD from satellite measurements by empirically correcting contributions of
                natural sources (dust and maritime aerosol) to the sub-micron AOD (Kaufman et al., 2005,
                155891). The MODIS-based estimate of anthropogenic AOD is about 0.033  over oceans,
                consistent with model assessments of 0.030—0.036 even though the total AOD from MODIS is
                25-40% higher than the models (Kaufman et al., 2005, 155891). This accounts for 21 ± 7% of
                the MODIS-observed total aerosol optical depth, compared with about 33%  of anthropogenic
                contributions estimated by the models. The anthropogenic fraction of AOD should be much
                larger over land (i.e., 47 ± 9% from a composite of several models) (Bellouin et al., 2005,
                155684), comparable to the 40% estimated by Yu et  al. (2006, 156173). Similarly, the non-
                spherical fraction from MISR or POLDER can be used to separate dust from spherical aerosol
                (Kahn et al., 2001,  190969; Kalashnikova and Kahn, 2006, 190962), providing another
                constraint for distinguishing anthropogenic from natural aerosols.
                     There have been several estimates of anthropogenic component of DRF in recent years.
                Table 9-10 lists such estimates of anthropogenic component of TOADRF that are from model
                simulations (Schulz et al., 2006, 190381) and constrained to some degree by satellite
                observations (Bellouin et al., 2005, 155684: Bellouin et al., 2008, 189999: Christopher et al.,
                2006, 155729: Chung et al., 2005, 155733: Kaufman et al., 2005,  155891: Matsui et al., 2006,
                190495: Quaas et al., 2008, 190916: Yu et al., 2006,  156173: Zhao et al., 2008, 190936). The
                satellite-based clear-sky DRF by anthropogenic aerosols is estimated to be -1.1 ±0.37 W/m2
                over ocean, about a factor of 2 stronger than model simulated -0.6 W/m2. Similar DRF
                estimates are rare over land, but a few studies do suggest that the anthropogenic DRF over
                land is much more negative than that over ocean (Bellouin et al., 2005, 155684: Bellouin et al.,
                2008, 189999: Yu et al., 2006, 156173). On global average, the measurement-based estimate of
                anthropogenic DRF ranges from -0.9 to -1.9 W/m2, again stronger than the model-based
                estimate of-0.8 W/m2. Similar to DRF estimates for total aerosols, satellite-based estimates of
                anthropogenic component of DRF are rare over land.
                     On global average, anthropogenic aerosols are generally more absorptive than natural
                aerosols. As such the anthropogenic component of DRF is much more negative at the surface
                than at TOA. Several observation-constrained studies estimate that the global average, clear-
                sky, anthropogenic component of DRF at the surface ranges from -4.2 to -5.1 W/m  (Bellouin
                et al., 2005, 155684: Chung et al., 2005, 155733: Matsui et al., 2006, 190495: Yu et al., 2004,
                190926), which is about a factor of 2 larger in magnitude than the model estimates (e.g.,
                Reddy et al., 2005, 190208).
                     Uncertainties in estimates of the anthropogenic  component of aerosol DRF are greater
                than for the total aerosol, particularly over land. An uncertainty analysis (Yu et al., 2006,
                156173) partitions the uncertainty for the global average anthropogenic DRF between land and
                ocean more or less evenly. Five parameters, namely  fine-mode fraction (ff) and anthropogenic
                fraction of fine-mode fraction (faf) over both land and ocean, and T over ocean, contribute
                nearly 80% of the overall uncertainty in the anthropogenic DRF estimate, with individual
                shares ranging from 13-20% (Yu et al., 2006, 156173). These uncertainties presumably
                represent a lower bound because the sources of error are assumed to be independent.
                Uncertainties associated with several parameters are also not well defined. Nevertheless, such
                uncertainty analysis is useful for guiding future research and documenting advances in
                understanding.
    December 2009                                        9-109
    

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    Table 9-10.   Estimates of anthropogenic components of aerosol optical depth (Tant) and clear-sky
                   DRF at the TOA from model simulations.
                                    Ocean
     Land
    Global
                                                                                               Estimated uncertainty or
    Tan.
    Kaufman et al. (2005. 155891) 0.033
    Bellouin et al. (2005, 155684) 0.028
    Chung etal. (2005. 155733)
    Yu et al. (2006, 156173) 0.031
    Christopher et al. (2006,
    155729)
    Matsui and Pielke (2006,
    190495)
    Quaas etal. (2008. 190916)
    Bellouin et al. (2008, 1899991 0.021
    Zhao etal. (2008, 190936)
    Schulz et al. (2006, 190381J 0-022
    DRF T
    (W/m2) lant
    -1.4
    -0.8 0.13
    
    -1.1 -.088
    -1.4
    -1.6
    -0.7
    -0.6 0.107
    -1.25
    -0.59 0.065
    model diversity tor UKh
    DRF -.- DRF
    (W/m2) lant (W/m2)
    30%
    0.062 -1.9 15%
    -1.1
    ,, a nn/|o 1, 47% (ocean), 845 (land), and
    "1'a U'U4B "1-J 62% (global)
    65%
    30°S-30°N oceans
    -1.8 -0.9 45%
    Update to Bellouin etal. (2005,
    -3.3 0.043 -1.3 1556841 with MODIS Collection 5
    data
    35%
    -114 0036 -077 30-40%; same emissions
    prescribed for all models
    Sources: Schulz et al., (2006,1903811 approaches constrained by satellite observations, Kaufman et al. (2005,155891
    156173): Christopher et al. (2006,1557291: Matsui and Pielke (2006,1904951: Quaas et al. (2008,1909161: Zhao et al.
               I; Bellouin et al. (2005,1556841 2008; Chung et al. (2005,1557331: Yu et al. (2006,
               (2008, 1909361.
    9.3.3.5.   Aerosol-Cloud Interactions and  Indirect Forcing
                     Satellite views of the Earth show a planet whose albedo is dominated by dark oceans and
                 vegetated surfaces, white clouds, and bright deserts. The bright white clouds overlying darker
                 oceans or vegetated surface demonstrate the significant effect that clouds have on the Earth's
                 radiative balance. Low clouds reflect incoming sunlight back to space, acting to cool the
                 planet, whereas high clouds can trap outgoing terrestrial radiation and act to warm the planet.
                 In the Arctic, low clouds have also been shown to warm the surface (Garrett and Zhao, 2006,
                 190570). Changes in cloud cover, in cloud vertical development, and cloud optical properties
                 will have strong radiative and therefore, climatic impacts. Furthermore, factors that change
                 cloud development will also change precipitation processes. These changes may alter amounts,
                 locations and intensities of local and regional rain and snowfall, creating droughts, floods and
                 severe weather.
                     Cloud droplets form on a subset of aerosol particles called cloud condensation nuclei
                 (CCN). In general, an increase in aerosol leads to an increase in CCN and an increase in drop
                 concentration.  Thus, for the same amount of liquid water in a cloud, more available CCN will
                 result in a  greater number but smaller  size of droplets (Twomey, 1977, 190533). A cloud with
                 smaller but more numerous droplets will be brighter and reflect more sunlight to space, thus
                 exerting a  cooling effect. This is the first aerosol indirect radiative effect, or "albedo effect."
                 The effectiveness of a particle as a CCN depends on its size and composition so that the degree
                 to which clouds become brighter for a given aerosol perturbation, and therefore the extent of
                 cooling, depends on the aerosol size distribution and its size-dependent composition. In
                 addition, aerosol perturbations to cloud microphysics may involve feedbacks;  for example,
                 smaller drops are less likely to collide and coalesce; this will inhibit growth, suppressing
                 precipitation, and possibly increasing cloud lifetime (Albrecht, 1989, 045783). In this case
                 clouds may exert an even stronger cooling effect.
                     A distinctly  different aerosol effect on clouds exists in thin Arctic clouds (LWP <25 gm"2)
                 having low emissivity. Aerosol has been shown to increase the longwave emissivity in  these
                 clouds, thereby warming the surface (Garrett  and Zhao, 2006, 190570; Lubin and Vogelmann,
                 2006, 190466).
                     Some aerosol particles, particularly black carbon and dust, also act as ice nuclei (IN) and
                 in so doing, modify the  microphysical properties of mixed-phase and ice-clouds. An increase
                 in IN will generate more ice crystals, which grow at the expense of water droplets due to the
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                 difference in vapor pressure over ice and water surfaces. The efficient growth of ice particles
                 may increase the precipitation efficiency. In deep convective, polluted clouds there is a delay
                 in the onset of freezing because droplets are smaller. These clouds may eventually precipitate,
                 but only after higher altitudes are reached that result in taller cloud tops, more lightning and
                 greater chance of severe weather (Andreae et al., 2004, 155658; Rosenfeld and Lansky, 1998,
                 190230). The present state of knowledge of the nature and abundance of IN, and ice formation
                 in clouds is extremely poor. There is some observational evidence of aerosol influences on ice
                 processes, but a clear link between aerosol, IN concentrations, ice crystal concentrations and
                 growth to precipitation has not been established. This report therefore only peripherally
                 addresses ice processes. More information can be found in a review by the WMO/IUGG
                 International Aerosol-Precipitation Scientific Assessment (Levin and Cotton, 2008, 190375).
                     In addition to their roles as CCN and IN, aerosols also absorb and scatter light, and
                 therefore they can change atmospheric conditions (temperature, stability, and surface  fluxes)
                 that influence cloud development and properties (Ackerman et al., 2000, 002987: Hansen et
                 al., 1997, 043104). Thus, aerosols affect clouds through changing cloud droplet size
                 distributions, cloud particle phase, and by changing the atmospheric environment of the cloud.
    
    
    
    9.3.3.6.    Remote Sensing of Aerosol-Cloud Interactions and Indirect  Forcing
    
                     The AVHRR satellite instruments have observed relationships between columnar aerosol
                 loading, retrieved cloud microphysics, and cloud brightness over the Amazon Basin that are
                 consistent with the theories explained above (Feingold et al., 2001, 190544: Kaufman and
                 Fraser, 1997, 190958: Kaufman and Nakajima,  1993, 190959), but do not necessarily prove a
                 causal relationship. Other studies have linked cloud and aerosol microphysical parameters or
                 cloud albedo and droplet size using satellite data applied over the entire global oceans (Han et
                 al., 1998, 190594: Nakajima et al., 2001,190552: Wetzel and Stowe, 1999, 190636). Using
                 these correlations with estimates of aerosol increase from the pre-industrial era, estimates of
                 anthropogenic aerosol indirect radiative forcing fall into the range of-0.7 to -1.7 W/m2
                 (Nakajima et al., 2001,190552).
                     Introduction of the more modern instruments (POLDER and MODIS) has allowed more
                 detailed observations of relationships between aerosol and cloud parameters. Cloud cover can
                 both decrease and  increase with increasing aerosol loading (Kaufman et al., 2005, 155891:
                 Koren et al., 2004, 190187: Koren et al., 2005, 190188: Matheson et al., 2005, 190494:
                 Sekiguchi et al., 2003,  190385: Yu et al., 2007, 093173). The same is true of LWP (Han et al.,
                 2002, 049181: Matsui et al., 2006, 190498). Aerosol absorption appears to be an important
                 factor in determining how cloud cover will respond to increased aerosol loading (Jiang and
                 Feingold, 2006, 190976: Kaufman  and Koren, 2006, 190951: Koren et al., 2008, 190193).
                 Different responses of cloud cover to  increased aerosol could also be correlated with
                 atmospheric thermodynamic and moisture structure (Yu et al., 2007, 093173). Observations in
                 the MODIS data show that aerosol loading correlates with enhanced convection and greater
                 production of ice anvils in the summer Atlantic Ocean (Koren et al., 2005, 190188), which
                 conflicts with previous results that used AVHRR and could not isolate convective systems
                 from shallow clouds (Sekiguchi et al., 2003, 190385).
                     In recent years,  surface-based remote sensing has also been applied to address aerosol
                 effects on cloud microphysics. This method offers some interesting insights, and is
                 complementary  to the global satellite view. Surface remote sensing can only be applied at a
                 limited number of locations, and therefore lacks the global satellite view. However, these
                 surface stations yield high temporal resolution data and because they sample aerosol below,
                 rather than adjacent to clouds they do not suffer from "cloud contamination." With the
                 appropriate instrumentation (lidar) they can measure the local aerosol entering the clouds,
                 rather than a column-integrated aerosol optical depth. Under well-mixed conditions, surface in
                 situ aerosol measurements can be used.  Surface remote-sensing  studies are discussed  in more
                 detail below, although the main science issues are common to satellite remote sensing.
                     Feingold et al. (2001, 190544) used data collected at the ARM Southern Great Plains
                 (SGP) site to allow simultaneous retrieval of aerosol and cloud properties. A combination of a
                 Doppler cloud radar  and a microwave radiometer was used to retrieve cloud drop effective
                 radius re profiles in non-precipitating (radar reflectivity Z <-17 dBZ), ice-free clouds.
                 Simultaneously, sub-cloud aerosol extinction profiles were measured with a lidar to quantify
                 the response of drop sizes to changes  in aerosol properties. Cloud data were binned according
                 to liquid water path (LWP) as measured with a microwave radiometer, consistent with
                 Twomey's (1977, 190533) conceptual view of the aerosol impact on cloud microphysics. With
                 high temporal/spatial resolution data (on the order of 20s or 1 OOs of meters), realizations of
                 aerosol-cloud interactions at the large eddy scale were obtained, and quantified in terms of the
                 relative decrease in re in response to a relative increase in aerosol extinction (din re/din
                 extinction), as shown in Figure 9-70. Examining the dependence in this way reduces reliance
                 on absolute measures of cloud and aerosol parameters and minimizes sensitivity to
                 measurement error, provided errors are unbiased. This formulation permitted these responses
                 to be related to cloud microphysical theory. Restricting the examination to updrafts only (as
                 determined from the radar Doppler signal) permitted examination of the role of updraft in
                 determining the response of re to changes in aerosol (via changes in drop number
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                concentration Nd). Analysis of data from 7 days showed that turbulence intensifies the aerosol
                impact on cloud microphysics.
                     In addition to radar/microwave radiometer retrievals of aerosol and cloud properties,
                measurements of cloud optical depth by surface based radiometers such as the MFRSR
                (Michalsky et al., 2001, 190537) have been used in combination with measurements of cloud
                LWP by microwave radiometer to measure an average value of re during daylight when the
                solar elevation angle is sufficiently high (Min and Harrison, 1996, 190538). Using this
                retrieval, Kim et al. (2003, 155899) performed analyses of the re response to changes in
                aerosol at the same continental site, using a surface measurement of the aerosol light scattering
                coefficient instead of using extinction near cloud base as a proxy for CCN. Variance in LWP
                was shown to explain most of the variance in cloud optical depth, exacerbating detection of an
                aerosol effect. Although a decrease in re was observed with increasing scattering coefficient,
                the relation was not strong, indicative of other influences on re and/or decoupling between the
                surface and cloud layer. A similar study was conducted by Garrett et al. (2004, 190568) at a
                location in the Arctic.
                               E
                               =1
                                              April 3  1998
                                             IE
    
                                           0.07   • LWP:  100-1 10  g  m"
    
                                       -   0.09   •LWP:  110-121  g  m"
    
                                           0.09   eLWP:  121-133  g  m'
    
                                             i     i  i  i  i  i i
                                                                                   .00
                                                Source: Adapted with Permission of the American Geophysical Union from Feingold et al. (2003, 190551).
    Figure 9-70.
    Scatter plots showing mean cloud drop effective radius (re) versus aerosol
    extinction coefficient (unit: km-1) for various liquid water path (LWP) bands on
    April 3, 1998 at ARM SGP site.
                     They suggested that summertime Arctic clouds are more sensitive to aerosol perturbations
                than clouds at lower latitudes. The advantage of the MFRSR/microwave radiometer
                combination is that it derives re from cloud optical depth and LWP and it is not as sensitive to
                large drops as the radar is. A limitation is that it can be applied only to clouds with extensive
                horizontal cover during daylight hours.
                     More recent data analyses by Feingold et al. (2003, 190551X Kim et al. (2008, 130785)
                and McComiskey et al. (2008, 190525) at a variety of locations, and modeling work (Feingold,
                2003, 190547) have investigated (i) the use of different proxies for cloud condensation nuclei,
                such as the light scattering coefficient and aerosol index; (ii) sensitivity of cloud
                microphysical/optical properties to controlling factors such as aerosol size distribution,
                entrainment, LWP, and updraft velocity; (iii) the effect of optical- as opposed to radar-
                retrievals of drop size; and (iv) spatial heterogeneity. These studies have reinforced the
                importance of LWP and vertical velocity as controlling parameters. They have also begun to
                reconcile the reasons for the large discrepancies between various approaches, and platforms
                (satellite, aircraft in situ, and surface-based remote sensing). These investigations are
                important because satellite measurements that use a similar approach are being employed in
                GCMs to represent the albedo indirect effect (Quaas and Boucher, 2005, 190573). In fact, the
                weakest albedo indirect effect in IPCC (2007, 092765) derives from satellite measurements
                that have very weak responses of re to changes in aerosol. The relationship between these
                aerosol-cloud microphysical responses and cloud radiative forcing has been examined by
    December 2009
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                 McComiskey and Feingold (2008, 190517). They showed that for plane-parallel clouds, a
                 typical uncertainty in the logarithmic gradient of a re-aerosol relationship of 0.05 results in a
                 local forcing error of-3 to -10 W/m2, depending on the aerosol perturbation. This sensitivity
                 reinforces the importance of adequate quantification of aerosol effects on cloud microphysics
                 to assessment of the radiative forcing, i.e., the indirect effect. Quantification of these effects
                 from remote sensors is exacerbated by measurement errors. For example, LWP is measured to
                 an accuracy of 25 g m-2 at best, and since it is the thinnest clouds (i.e., low LWP) that are most
                 susceptible (from a radiative forcing perspective) to changes in aerosol, this measurement
                 uncertainty represents a significant uncertainty in whether the observed response is related to
                 aerosol, or to differences in LWP. The accuracy and spatial resolution of satellite-based LWP
                 measurements is much poorer and this represents a significant challenge. In some cases
                 important measurements are simply absent, e.g., updraft is not measured from satellite-based
                 remote sensors.
                     Finally, cloud radar data from CloudSat, along with the A-train aerosol data, is providing
                 great opportunity for inferring aerosol effects on  precipitation (e.g., Stephens  and Haynes,
                 2007, 190413). The aerosol effect on precipitation is far more complex than the albedo effect
                 because the instantaneous view provided by satellites makes it difficult to establish causal
                 relationships.
    
    
    
    9.3.3.7.   In Situ Studies of Aerosol-Cloud Interactions
    
                     In situ observations of aerosol effects on cloud microphysics date back to the 1950s and
                 1960s (Brenguier et al, 2000, 189966; Gunn and Phillips, 1957, 190595; Leaitch et al, 1992,
                 045270: Radke et al., 1989,  156034: Squires, 1958, 045608: Warner, 1968, 157114: Warner
                 and Twomey, 1967, 045616: to name a few). These studies showed that high concentrations of
                 CCN from anthropogenic sources, such as industrial pollution or the burning of sugarcane can
                 increase cloud droplet number concentration Nd, thus increasing cloud microphysical stability
                 and potentially reducing precipitation efficiency.  As in the case of remote sensing studies, the
                 causal link between aerosol perturbations and cloud microphysical responses (e.g., re  or Nd) is
                 much better established than the relationship between aerosol and changes in cloud fraction,
                 LWC, and precipitation (see also Levin  and Cotton, 2008, 190375).
                     In situ cloud measurements are usually regarded as "ground truth" for satellite retrievals
                 but in fact there is considerable uncertainty in measured parameters such liquid water content
                 (LWC), and size distribution, which forms the basis of other calculations such as drop
                 concentration, re and extinction. It is not uncommon to see discrepancies in LWC on the order
                 of 50% between different instruments, and cloud drop size distributions are difficult to
                 measure, particularly for droplets <10 um where  Mie scattering oscillations generate
                 ambiguities in drop size. Measurement uncertainty in re from in situ probes is assessed, for
                 horizontally homogeneous clouds, to be on the order of 15- 20%, compared to  10% for
                 MODIS and 15-20% for other spectral measurements (Feingold et al., 2003, 190551). As with
                 remote measurements it is prudent to consider relative (as opposed to absolute) changes in
                 cloud microphysics related to relative changes in aerosol. An added consideration is that in situ
                 measurements typically represent a very small sample of the atmosphere akin to a thin pencil
                 line through a large volume. For an aircraft flying at 100 m/s and sampling at 1 Hz, the sample
                 volume is on the order of 10 cm . The larger spatial sampling of remote sensing has the
                 advantage of being more representative but it removes small-scale (i.e., sub sampling volume)
                 variability, and therefore, may obscure important cloud processes.
                     Measurements at a wide variety of locations around the world have shown that increases
                 in aerosol concentration lead to increases in Nd. However the rate of this increase is highly
                 variable and always sub-linear, as exemplified by the compilation of data in Ramanathan et al.
                 (2001, 042681). This is because, as discussed previously, Nd is a function of numerous
                 parameters in addition to aerosol number concentration, including size distribution, updraft
                 velocity (Leaitch et al.,  1996, 190354), and composition. In stratocumulus clouds,
                 characterized by relatively low vertical velocity (and low supersaturation) only a small fraction
                 of particles can be activated whereas in vigorous cumulus clouds that have high updraft
                 velocities, a much larger fraction of aerosol particles is activated. Thus the ratio of Nd to
                 aerosol particle number concentration is highly variable.
                     In recent years there has been a concerted  effort to reconcile measured Nd concentrations
                 with those calculated based on observed aerosol size and composition, as well as updraft
                 velocity. These so-called "closure experiments" have demonstrated that on average, agreement
                 in Nd between these approaches is on the order of 20% (Conant et al., 2004, 190010). This
                 provides confidence in theoretical understanding of droplet activation, however, measurement
                 accuracy is not high enough to constrain the aerosol composition effects that have magnitudes
                 <20%.
                     One exception to the rule that more aerosol particles result in larger Nd is  the case of giant
                 CCN (sizes on the order of a few microns), which, in concentrations on the order of 1 cm3 (i.e.,
                 ~ 1% of the total concentration) can lead to significant suppression in cloud supersaturation
                 and reductions in Nd (O'Dowd et al., 1999, 090414). The measurement of these large particles
                 is difficult and hence the importance of this effect is hard to assess. These same giant CCN, at
                 concentrations as low as 1/liter, can significantly affect the initiation of precipitation in
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                 moderately polluted clouds (Johnson, 1982, 190973) and in so doing alter cloud albedo
                 (Feingold et al, 1999, 190540).
                     The most direct link between the remote sensing of aerosol-cloud interactions discussed
                 in Section 9.3.3.6 and in situ observations is via observations of relationships between drop
                 concentration Nd and CCN concentration. Theory shows that if re-CCN relationships are
                 calculated at constant LWP or LWC, their logarithmic slope is -1/3 that of the Nd-CCN
                 logarithmic slope (i.e., dlnre/dlnCCN = -1/3 dlnNd/ dlnCCN). In general, Nd-CCN slopes
                 measured in situ tend to be stronger than equivalent slopes obtained from remote sensing -
                 particularly in the case of satellite remote sensing (McComiskey and Feingold, 2008,
                 190517). There are a number of reasons for this: (i) in situ measurements focus on smaller
                 spatial scales and are more likely to observe the droplet activation process as opposed to
                 remote sensing that incorporates larger spatial scales and includes other processes such as drop
                 coalescence that reduce Nd, and  therefore the slope of the Nd- CCN relationship
                 (McComiskey et al., 2008, 190525). (ii) Satellite remote sensing studies typically do not sort
                 their data by LWP, and this has been shown to reduce the magnitude of the re-CCN response
                 (Feingold, 2003, 190547).
                     In conclusion, observational estimates of aerosol indirect radiative forcings are still in
                 their infancy. Effects on cloud microphysics that result in cloud brightening have to be
                 considered along with effects on cloud lifetime, cover, vertical development and ice
                 production. For in situ measurements, aerosol effects on cloud microphysics are reasonably
                 consistent (within ~ 20%) with theory but measurement uncertainties in remote sensing of
                 aerosol effects on clouds, as well as complexity associated with three-dimensional radiative
                 transfer, result in considerable uncertainty in radiative forcing. The higher order indirect
                 effects are poorly understood and even the sign of the microphysical response and forcing may
                 not always be the same. Aerosol  type and specifically the absorption properties of the aerosol
                 may cause different cloud responses. Early estimates of observationally based aerosol indirect
                 forcing range from -0.7 to -1.7 W/m2 (Nakajima et al., 2001,190552) and -0.6 to -1.2 W/m2
                 (Sekiguchi et al., 2003,  190385), depending on the estimate for aerosol increase from pre-
                 industrial times and whether aerosol effects on cloud fraction are also included in the estimate.
    9.3.4.  Outstanding Issues
                     Despite substantial progress, as summarized in Sections 9.3.2 and 9.3.3, most
                 measurement-based studies so far have concentrated on influences produced by the sum of
                 natural and anthropogenic aerosols on solar radiation under clear sky conditions. Important
                 issues remain:
                     •   Because accurate measurements of aerosol absorption are lacking and land surface
                         reflection values are uncertain, DRF estimates over land and at the ocean surface are
                         less well constrained than the estimate of TOA DRF over ocean.
                     •   Current estimates of the anthropogenic component of aerosol direct radiative forcing
                         have large uncertainties, especially over land.
                     •   Because there are very few measurements of aerosol absorption vertical distribution,
                         mainly from aircraft during field campaigns, estimates of direct radiative forcing of
                         above-cloud aerosols and profiles  of atmospheric radiative heating induced by
                         aerosol absorption are poorly constrained.
                     •   There is  a need to quantify aerosol impacts on thermal infrared radiation, especially
                         for dust.
                     •   The diurnal cycle of aerosol direct radiative forcing cannot be adequately
                         characterized with currently available, sun-synchronous, polar orbiting satellite
                         measurements.
                     •   Measuring aerosol,  cloud, and ambient meteorology contributions to indirect
                         radiative forcing remains a major challenge.
                     •   Long-term aerosol trends and their relationship to observed surface solar radiation
                         changes  are not well understood.
                     The current status and prospects for these areas are briefly discussed below.
    
    
           Measuring Aerosol Absorption and Single-Scattering Albedo
    
                     Currently, the accuracy of both in situ and remote sensing aerosol SSA measurements is
                 generally ± 0.03 at best, which implies that the inferred accuracy of clear sky aerosol DRF
                 would be larger than 1 W/m2  (see Chapter 1 of the CSSP SAP2.3). Recently developed
                 photoacoustic (Arnott et al., 1999, 020650)  and cavity ring down extinction cell (Strawa et al.,
                 2002, 190421) techniques for measuring aerosol absorption produce SSA with improved
                 accuracy over previous methods. However,  these methods are still experimental, and must be
                 deployed on aircraft. Aerosol absorption retrievals from satellites using the UV-technique have
                 large uncertainties associated with its sensitivity to the height of the aerosol layer(s) (Torres et
                 al., 2005, 190507), and it is unclear how the UV results can be extended to visible
                 wavelengths. Views in and out of sunglint can be used to retrieve total aerosol extinction and
                 scattering, respectively, thus constraining aerosol absorption over oceans (Kaufman et al.,
                 2002, 190955). However, this technique requires retrievals of aerosol scattering properties,
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                 including the real part of the refractive index, well beyond what has so far been demonstrated
                 from space. In summary, there is a need to pursue a better understanding of the uncertainty in
                 SSA from both in situ measurements and remote sensing retrievals and, with this knowledge,
                 to synthesize different data sets to yield a characterization of aerosol absorption with well-
                 defined uncertainty (Leahy et al., 2007, 190232). Laboratory studies of aerosol absorption of
                 specific known composition are also needed to interpret in situ measurements and remote
                 sensing retrievals and to provide updated database of particle absorbing properties for models.
    
    
           Estimating the Aerosol Direct Radiative Forcing over Land
    
                     Land surface reflection is large, heterogeneous, and anisotropic, which complicates
                 aerosol retrievals and DRF determination from satellites. Currently, the aerosol retrievals over
                 land have relatively lower accuracy than those over ocean (Section 9.3.2.5) and satellite data
                 are rarely used alone for estimating  DRF over land (Section 9.3.3). Several issues need to be
                 addressed, such as developing appropriate angular models for aerosols over land (Patadia et
                 al., 2008, 190558) and improving land surface reflectance characterization. MODIS and MISR
                 measure land surface reflection wavelength dependence and angular distribution at high
                 resolution (Martonchik et al., 1998, 190484; Martonchik et al., 2002, 190490; Moody et al.,
                 2005, 190548). This offers a promising opportunity for inferring the aerosol direct radiative
                 forcing over land from satellite measurements of radiative fluxes (e.g., CERES) and from
                 critical reflectance techniques (Fraser and Kaufman, 1985, 190567: Kaufman, 1987, 190960).
                 The aerosol direct radiative forcing  over land depends  strongly on aerosol absorption and
                 improved measurements of aerosol absorption are required.
    
    
           Distinguishing Anthropogenic from Natural Aerosols
    
                     Current estimates of anthropogenic  components of AOD and direct radiative forcing have
                 larger uncertainties than total aerosol optical depth and direct radiative forcing, particularly
                 over land (see Section 9.3.3.4), because of relatively large uncertainties in the retrieved aerosol
                 microphysical properties (see Section 9.3.2). Future measurements should focus on improved
                 retrievals of such aerosol properties as size distribution, particle shape, and absorption, along
                 with algorithm refinement for better aerosol optical depth retrievals. Coordinated in situ
                 measurements offer a promising avenue  for validating  and refining satellite identification of
                 anthropogenic aerosols (Anderson et al., 2005, 189993: 2005, 189991). For satellite-based
                 aerosol type characterization, it is sometimes assumed  that all biomass-burning aerosol is
                 anthropogenic and all dust aerosol is natural (Kaufman et al., 2005, 155891). The better
                 determination of anthropogenic aerosols requires a quantification of biomass burning ignited
                 by lightning (natural origin) and mineral dust due to human induced changes of land
                 cover/land use and climate (anthropogenic origin). Improved emissions inventories and better
                 integration of satellite observations with models seem likely to reduce the uncertainties in
                 aerosol source attribution.
    
    
           Profiling the  Vertical Distributions of Aerosols
    
                     Current aerosol profile data are far from adequate  for quantifying the aerosol radiative
                 forcing and atmospheric response to the  forcing. The data have limited spatial and temporal
                 coverage, even for current spaceborne lidar measurements.  Retrieving aerosol extinction
                 profile from lidar measured attenuated backscatter is subject to large uncertainties resulting
                 from aerosol type characterization. Current space-borne Lidar measurements are also not
                 sensitive to aerosol absorption. Because  of lack of aerosol vertical distribution observations,
                 the estimates of DRF in cloudy conditions and dust DRF in the thermal infrared remain highly
                 uncertain (Lubin et al., 2002, 190463: Schulz et al., 2006, 190381: Sokolik et al., 2001,
                 190404). It also remains challenging to constrain the aerosol-induced atmospheric heating rate
                 increment that is essential for assessing atmospheric responses to  the aerosol radiative forcing
                 (e.g., Feingold et al., 2005, 190550: Lau et al., 2006, 190223: Yu et al., 2002, 190923).
                     Progress in the foreseeable future is likely to come from (1) better use of existing, global,
                 space-based backscatter lidar data to constrain model simulations, and (2) deployment of new
                 instruments, such as high-spectral-resolution lidar  (HSRL), capable of retrieving both
                 extinction and backscatter from space. The HSRL lidar system will be deployed on the
                 EarthCARE satellite mission tentatively  scheduled for  2013
                 Chttp://asimov/esrin.esi.it/esaLP/ASESMYNW9SC_Lpearthcare_l .html).
    
    
           Characterizing the Diurnal Cycle  of Aerosol Direct Radiative Forcing
    
                     The diurnal variability of aerosol can be large, depending on location and aerosol type
                 (Smirnov et al., 2002, 190398), especially in wildfire situations, and in places where boundary
                 layer aerosols hydrate or otherwise change significantly during the day. This cannot be
                 captured by currently available, sun-synchronous, polar orbiting satellites. Geostationary
                 satellites provide adequate time resolution (Christopher and Zhang, 2002, 190031: Wang et
                 al., 2003, 157106), but lack the information required to characterize aerosol types. Aerosol
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                 type information from low earth orbit satellites can help improve accuracy of geostationary
                 satellite aerosol retrievals (Costa et al, 2004, 190006: 2004, 192022). For estimating the
                 diurnal cycle of aerosol DRF, additional efforts are needed to adequately characterize the
                 anisotropy of surface reflection (Yu et al., 2004, 190926) and daytime variation of clouds.
    
    
           Studying Aerosol-Cloud Interactions and Indirect Radiative Forcing
    
                     Remote sensing estimates of aerosol indirect forcing are still rare and uncertain.
                 Improvements are needed for both aerosol characterization and measurements of cloud
                 properties, precipitation, water vapor, and temperature profiles. Basic processes still need to be
                 understood on regional and global scales. Remote  sensing observations of aerosol-cloud
                 interactions and aerosol indirect forcing are for the most part based on simple correlations
                 among variables, from which cause-and-effects cannot be deduced. One difficulty in inferring
                 aerosol effects on clouds from the observed relationships is separating aerosol from
                 meteorological effects, as aerosol loading itself is often correlated with the meteorology. In
                 addition, there are systematic errors and biases in satellite aerosol retrievals for partly cloud-
                 filled scenes. Stratifying aerosol and cloud data by liquid water content, a key step in
                 quantifying the albedo (or first) indirect effect, is usually missing. Future work will  need to
                 combine satellite observations with in situ validation and modeling interpretation. A
                 methodology for integrating observations (in situ and remote) and models at the range of
                 relevant temporal/spatial scales is crucial to improve understanding of aerosol indirect effects
                 and aerosol-cloud interactions.
    
    
           Quantifying Long-Term Trends of Aerosols at Regional Scales
    
                     Because secular changes are subtle and are superposed on seasonal and other natural
                 variability, this requires the construction of consistent, multi-decadal records of climate-quality
                 data. To be meaningful, aerosol trend analysis must be performed on a regional basis. Long-
                 term trends of aerosol optical depth have been studied using measurements from surface
                 remote sensing stations (e.g., Augustine et al., 2008, 189913: Hoyt and Frohlich, 1983,
                 190621: Luo et al., 2001,  190467) and historic satellite sensors (Massie et al., 2004, 190492:
                 Mishchenko and Geogdzhayev, 2007, 190545: Mishchenko et al., 2007, 190542: Zhao et al.,
                 2008,  190935). An emerging multiyear climatology of high quality AOD data from  modern
                 satellite sensors (e.g., Kahn et al., 2005, 190966: Remer et al., 2008, 190224) has been used to
                 examine the interannual variations of aerosol (e.g., Koren et al., 2007,  190189: Mishchenko
                 and Geogdzhayev, 2007, 190545)
                     and contribute significantly to the study of aerosol trends. Current observational
                 capability needs to be continued to avoid any data  gaps. A synergy of aerosol products from
                 historical, modern and future sensors is needed to construct as long a record as possible. Such
                 a data synergy can build upon understanding and reconciliation of AOD differences among
                 different sensors or platforms (Jeong  et al., 2005, 190977). This requires overlapping data
                 records for multiple sensors. A close examination of relevant issues associated with individual
                 sensors is urgently needed, including sensor calibration, algorithm assumptions, cloud
                 screening, data sampling and aggregation, among others.
    
    
           Linking Aerosol Long-Term Trends with Changes of Surface Solar Radiation
    
                     Analysis of the long-term surface solar radiation record suggests significant trends during
                 past decades (e.g., Alpert et al., 2005, 190047: Pinker et al., 2005, 190569: Stanhill  and
                 Cohen, 2001, 042121: Wild et al., 2005, 156156). Although a significant and widespread
                 decline in surface total solar radiation (the sum of direct and diffuse irradiance) occurred up to
                 1990 (so-called solar dimming), a sustained increase has been observed during the subsequent
                 decade. Speculation suggests that such trends result from decadal changes of aerosols and the
                 interplay of aerosol direct and indirect radiative forcing (Norris and Wild, 2007, 190555:
                 Ruckstuhl et al., 2008, 190356: Stanhill and Cohen, 2001, 042121: Streets et al., 2006,
                 190425: Wild et al., 2005, 156156). However, reliable observations of aerosol trends are
                 required to test these ideas. In addition to aerosol optical depth, changes in aerosol
                 composition must also be quantified,  to account for changing industrial practices,
                 environmental regulations, and biomass burning emissions (Novakov et al., 2003, 048398:
                 Streets and Aunan, 2005, 156106: Streets et al., 2004, 190423). Such compositional changes
                 will affect the aerosol SSA and size distribution, which in turn will affect the surface solar
                 radiation (e.g., Qian et al., 2007, 190572). However, such data are currently rare and subject to
                 large uncertainties. Finally, a better understanding  of aerosol-radiation-cloud interactions and
                 trends in cloudiness, cloud albedo, and  surface albedo is badly needed to attribute the observed
                 radiation changes to aerosol  changes  with less ambiguity.
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    9.3.5.  Concluding  Remarks
                     Since the concept of aerosol-radiation-climate interactions was first proposed around
                 1970, substantial progress has been made in determining the mechanisms and magnitudes of
                 these interactions, particularly in the last 10 years. Such progress has greatly benefited from
                 significant improvements in aerosol measurements and increasing sophistication of model
                 simulations. As a result, knowledge of aerosol properties and their interaction with solar
                 radiation on regional and global scales is much improved. Such progress plays a unique role in
                 the definitive assessment of the global anthropogenic radiative forcing, as "virtually certainly
                 positive" in IPCC AR4 (Haywood  and Schulz, 2007, 190600).
    
    
           In Situ Measurements  of Aerosols
    
                     New in situ instruments such as aerosol mass spectrometers, photoacoustic techniques,
                 and cavity ring down cells provide high accuracy and fast time resolution measurements of
                 aerosol chemical and optical properties. Numerous focused field campaigns and the emerging
                 ground-based aerosol networks are improving regional aerosol chemical, microphysical, and
                 radiative property characterization. Aerosol closure studies of different measurements indicate
                 that measurements of submicrometer, spherical sulfate and carbonaceous particles have a
                 much better accuracy than that for dust-dominated aerosol. The accumulated comprehensive
                 data sets of regional aerosol properties provide a rigorous "test bed" and strong constraint for
                 satellite retrievals and model simulations of aerosols and their direct radiative forcing.
    
    
           Remote Sensing  Measurements of Aerosols
    
                     Surface networks, covering various aerosol regimes around the globe, have been
                 measuring aerosol optical depth with an accuracy of 0.01-0.02, which is adequate for
                 achieving the accuracy of 1 W/m2 for cloud-free TOA DRF. On the other hand, aerosol
                 microphysical properties retrieved from these networks, especially SSA, have relatively large
                 uncertainties and are only available in very limited conditions. Current satellite sensors can
                 measure AOD with an accuracy of about 0.05 or 15-20% in most cases. The implementation of
                 multi-wavelength, multi-angle,  and polarization measuring capabilities has also made it
                 possible to measure  particle properties (size, shape, and absorption) that are essential for
                 characterizing aerosol  type and estimating anthropogenic component of aerosols.  However,
                 these microphysical measurements are more uncertain than AOD measurements.
    
    
           Observational Estimates of Clear-Sky Aerosol Direct Radiative Forcing
    
                     Closure studies based on focused field experiments reveal DRF uncertainties of about
                 25% for sulfate/carbonaceous aerosol and 60% for dust at regional scales. The high-accuracy
                 of MODIS, MISR and POLDER aerosol products and broadband flux measurements from
                 CERES make it feasible to obtain observational constraints for aerosol TOA DRF at a global
                 scale, with relaxed requirements for measuring particle microphysical properties.  Major
                 conclusions from the assessment are:
                     •    A number  of satellite-based approaches consistently estimate the clear-sky diurnally
                         averaged TOA  DRF (on solar radiation) to be about -5.5 ± 0.2 W/m2 (mean ±
                         standard error from various methods) over global ocean. At the ocean surface, the
                         diurnally averaged DRF is estimated to be -8.7 ± 0.7 W/m2. These values are
                         calculated  for the difference between today's measured total aerosol (natural plus
                         anthropogenic) and the absence of all aerosol.
                     •    Overall, in comparison to that over ocean, the DRF  estimates over land  are more
                         poorly constrained by observations and have larger uncertainties. A few satellite
                         retrieval and  satellite-model integration yield the overland clear-sky diurnally
                         averaged DRF of -4.9 ± 0.7 W/m2 and -11.8 ± 1.9 W/m2 at the TOA and surface,
                         respectively.  These values over land are calculated for the difference between total
                         aerosol and the complete absence of all aerosol.
                     •    Use of satellite measurements of aerosol microphysical properties yields that on a
                         global ocean average, about 20% of AOD is contributed by human activities and the
                         clear-sky TOA DRF by anthropogenic aerosols is -1.1 ± 0.4 W/m . Similar DRF
                         estimates are rare over land, but a few measurement-model integrated studies do
                         suggest much more negative DRF over land than over ocean.
                     •    These satellite-based DRF estimates are much greater than the model-based
                         estimates, with differences much larger at regional scales than at a global scale.
    
    
           Measurements of Aerosol-Cloud Interactions and Indirect Radiative Forcing
    
                     In situ measurement of cloud properties and aerosol effects on cloud microphysics suggest
                 that theoretical understanding of the activation process for water cloud is reasonably well-
                 understood. Remote sensing of aerosol effects on droplet size associated with the  albedo effect
                 tends to underestimate the magnitude of the response compared to in situ measurements.
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                 Recent efforts trace this to a combination of lack of stratification of data by cloud water, the
                 relatively large spatial scale over which measurements are averaged (which includes variability
                 in cloud fields, and processes that obscure the aerosol-cloud processes), as well as
                 measurement uncertainties (particularly in broken cloud fields). It remains a major challenge
                 to infer aerosol number concentrations from satellite measurements. The present state of
                 knowledge of the nature and abundance of IN, and ice formation in clouds is extremely poor.
                     Despite the substantial progress in recent decades, several important issues remain, such
                 as measurements of aerosol size distribution, particle shape, absorption, and vertical profiles,
                 and the detection of aerosol long-term trend and establishment of its connection with the
                 observed trends of solar radiation reaching the surface, as discussed in Section 9.3.4.
                 Furthering the understanding of aerosol impacts on climate requires a coordinated research
                 strategy to improve the measurement accuracy and use the measurements to validate and
                 effectively constrain model simulations. Concepts of future research in measurements are
                 discussed in Chapter 4 "Way Forward" (of the CCSP SAP2.3).
    9.3.6.  Modeling the Effect of Aerosols on  Climate
    9.3.6.1.    Introduction
                     The IPCC Fourth Assessment Report (AR4) (IPCC, 2007, 092765) concludes that man's
                 influence on the warming climate is in the category of "very likely". This conclusion is based
                 on, among other things, the ability of models to simulate the global and, to some extent,
                 regional variations of temperature over the past 50-100 years. When anthropogenic effects are
                 included, the simulations can reproduce the observed warming (primarily for the past 50
                 years); when they are not, the models do not get very much warming at all. In fact, all of the
                 models runs for the IPCC AR4 assessment (more than 20) produce this distinctive result,
                 driven by the greenhouse gas increases that have been observed to occur.
                     These results were produced in models whose average global warming associated with a
                 doubled CO2 forcing of 4 W/m was  about 3°C. This translates into a climate sensitivity
                 (surface temperature change per forcing) of about 0.75°C/(W/m2). The determination of
                 climate sensitivity is crucial to projecting the future impact of increased greenhouse gases, and
                 the credibility of this projected value relies on the ability of these models to simulate the
                 observed temperature changes over the past century. However, in producing the observed
                 temperature trend in the past, the models made use of very uncertain aerosol forcing. The
                 greenhouse gas change by itself produces warming in models that exceeds that observed by
                 some 40% on average (IPCC, 2007, 092765). Cooling associated with aerosols reduces this
                 warming to the observed level. Different climate models use differing aerosol forcings, both
                 direct (aerosol scattering and absorption of short and longwave radiation) and indirect (aerosol
                 effect on cloud cover reflectivity and lifetime), whose magnitudes vary markedly from one
                 model to the next. Kiehl (2007, 190949) using nine of the  IPCC (2007, 092765) AR4 climate
                 models found that they had a factor of three forcing differences in the aerosol contribution for
                 the 20th century. The differing aerosol forcing is the prime reason why models whose climate
                 sensitivity varies by almost a factor of three can produce the observed trend. It was thus
                 concluded that the uncertainty in IPCC (2007, 092765) anthropogenic climate simulations for
                 the past century should really be much greater than stated  (Kerr, 2007, 190950: Schwartz  et al.,
                 2007, 190384), since, in general, models with low/high sensitivity to greenhouse warming
                 used weaker/stronger aerosol cooling to obtain the same temperature response (Kiehl, 2007,
                 190949). Had the situation been reversed and the low/high sensitivity models used strong/
                 weak aerosol forcing, there would have been a  greater divergence in model simulations of the
                 past century.
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    Figure 9-71.   Sampling the Arctic Haze. Pollution and smoke aerosols can travel long
                    distances, from mid-latitudes to the Arctic, causing "Arctic Haze." Photo taken
                    from the NASA DC-8 aircraft during the ARCTAS field experiment over Alaska in
                    April 2008. Credit: Mian Chin, NASA.
    
                    Therefore, the fact that a model has accurately reproduced the global temperature change
                in the past does not imply that its future forecast is accurate. This state of affairs will remain
                until a firmer estimate of radiative forcing (RF) by aerosols, in addition to that by greenhouse
                gases, is available.
                    Two different approaches are used to assess the aerosol effect on climate. "Forward
                modeling" studies incorporate different aerosol types and attempt to explicitly calculate the
                aerosol RF. From this approach, IPCC (2007, 092765) concluded that the best estimate of the
                global aerosol direct RF (compared with preindustrial times) is -0.5 (-0.9 to -0.1) W/m2. The
                RF due to the cloud albedo or brightness effect (also referred to as first indirect or Twomey
                effect) is estimated to be -0.7 (-1.8 to -0.3) W/m . No estimate was specified for the effect
                associated with cloud lifetime. The total negative RF due to aerosols  according  to IPCC (2007,
                092765) estimates is then -1.3 (-2.2 to -0.5) W/m2. In comparison, the positive radiative
                forcing (RF) from greenhouse gases (including tropospheric ozone) is estimated to be +2.9 ±
                0.3 W/m2; hence tropospheric aerosols reduce the influence from greenhouse gases by about
                45% (15-85%). This approach however inherits large uncertainties in aerosol amount,
                composition, and physical and optical properties in modeling of atmospheric aerosols. The
                consequences of these uncertainties are discussed in the next section.
                    The other  method of calculating aerosol forcing is called the "inverse approach" - it is
                assumed that the observed climate change is primarily the result of the known climate forcing
                contributions. If one further assumes a particular climate sensitivity (or a range  of
                sensitivities), one can determine what the total forcing had to be to produce the  observed
                temperature change.  The aerosol forcing is then deduced as a residual after subtraction of the
                greenhouse gas forcing along with other known forcings from the total value. Studies of this
                nature come  up with aerosol forcing ranges of-0.6 to -1.7 W/m2 (Knutti et al., 2002, 190178;
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                 Knutti et al., 2003, 190180); IPCC AR4 Chap.9); -0.4 to -1.6 W/m2 (Gregory et al., 2002,
                 190593): and -0.4 to -1.4 W/m2 (Stott, 2006, 190419). This approach however provides a
                 bracket of the possible range of aerosol forcing without the assessment of current knowledge
                 of the complexity of atmospheric aerosols.
                     This chapter of the CC SP SAP2.3 reviews the current state of aerosol RF in the global
                 models and assesses the uncertainties in these calculations. First representation of aerosols in
                 the forward global chemistry and transport models and the diversity of the model simulated
                 aerosol fields are discussed; then calculation of the aerosol direct and indirect effects in the
                 climate models is reviewed; finally the impacts of aerosols on climate model simulations and
                 their implications are assessed.
    
    
    
    9.3.6.2.    Modeling of Atmospheric Aerosols
    
                     The global aerosol modeling  capability has developed rapidly in the past decade. In the
                 late 1990s, there were only a few global models that were able to simulate one or two aerosol
                 components, but now there are a few dozen global models that simulate a comprehensive suite
                 of aerosols in the atmosphere. As introduced in Chapter 1 (of the CCSP  SAP2.3), aerosols
                 consist of a variety of species including dust, sea salt, sulfate, nitrate, and carbonaceous
                 aerosols (black and organic carbon) produced from natural and man-made sources with a wide
                 range of physical and optical properties. Because of the complexity of the processes and
                 composition, and highly inhomogeneous distribution of aerosols, accurately modeling
                 atmospheric aerosols and their effects remains a challenge. Models have to take into account
                 not only the aerosol and precursor emissions, but also the chemical transformation, transport,
                 and removal processes (e.g., dry and wet depositions) to simulate the aerosol mass
                 concentrations. Furthermore, aerosol particle size can grow in the atmosphere because the
                 ambient water vapor can condense on the aerosol particles. This "swelling" process, called
                 hygroscopic growth, is most commonly parameterized in the models as  a function of relative
                 humidity.
    
    
           Estimates of Emissions
    
                     Aerosols have various sources from both natural and anthropogenic processes. Natural
                 emissions include wind-blown mineral dust, aerosol and precursor gases from volcanic
                 eruptions, natural wild fires, vegetation, and oceans. Anthropogenic sources include emissions
                 from fossil fuel and biofuel combustion, industrial processes, agriculture practices, and human-
                 induced biomass  burning.
                     Following earlier attempts to quantify manmade primary emissions of aerosols (Penner et
                 al., 1993, 045457; Turco et al., 1983, 190529)  systematic work was undertaken in the late
                 1990s to calculate emissions of black carbon (BC) and organic carbon (OC), using fuel-use
                 data and measured emission factors (Cooke and Wilson, 1996, 190046; Cooke et al., 1999,
                 156365; Liousse et al., 1996, 078158). The work was extended in greater detail and with
                 improved attention to source-specific emission factors in Bond et al. (2004, 056389), which
                 provides global inventories of BC and OC for the year 1996, with regional  and source-
                 category discrimination that includes contributions from industrial, transportation, residential
                 solid-fuel combustion, vegetation and open biomass burning (forest fires, agricultural waste
                 burning, etc.), and diesel vehicles.
                     Emissions from natural sources—which include wind-blown mineral dust, wildfires, sea
                 salt, and volcanic eruptions—are less well quantified, mainly because of the difficulties of
                 measuring emission rates in the field and the unpredictable nature of the events. Often,
                 emissions must be inferred from ambient observations at some distance  from the actual source.
                 As an example, it was concluded (Lewis and Schwartz, 2004, 192023) that available
                 information on size-dependent sea salt production rates could only provide order-of-magnitude
                 estimates. The natural emissions in general can vary dramatically over space and time.
                     Aerosols can be produced from trace gases in the atmospheric via chemical reactions, and
                 those aerosols are called secondary aerosols, as distinct from primary aerosols that are directly
                 emitted to the atmosphere as aerosol particles. For example, most sulfate and nitrate aerosols
                 are secondary aerosols that are formed from their precursor gases, sulfur dioxide (SO2) and
                 nitrogen oxides (NO and NO2, collectively called NOX), respectively. Those sources have been
                 studied for many years and are relatively well known. By contrast, the sources of secondary
                 organic aerosols (SOA) are poorly understood, including emissions of their precursor gases
                 (called volatile organic compounds, VOC) from both natural and anthropogenic sources and
                 the atmospheric production processes.
                     Globally, sea salt and mineral dust dominate the total aerosol mass  emissions because of
                 the large source areas and/or large particle sizes. However, sea salt and dust also have shorter
                 atmospheric lifetimes because of their large particle size, and are radiatively less active than
                 aerosols with small particle size, such as sulfate, nitrate, BC, and particulate organic matter
                 (POM, which includes both carbon and non-carbon mass in the organic  aerosol), most of
                 which are anthropogenic in origin.
                     Because the  anthropogenic aerosol RF is usually evaluated (e.g., by the IPCC) as the
                 anthropogenic perturbation since the pre-industrial period, it is necessary to estimate the
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                 historical emission trends, especially the emissions in the pre-industrial era. Compared to
                 estimates of present-day emissions, estimates of historical emission have much larger
                 uncertainties. Information for past years on the source types and strengths and even locations
                 are difficult to obtain, so historical inventories from preindustrial times to the present have to
                 be based on limited knowledge and data. Several studies on historical emission inventories of
                 BC and OC (e.g., Bond et al, 2007, 190050: Fernandes et al, 2007, 190554: Ito  and Penne,
                 2005, 190626: Junker  and Liousse, 2008, 190971: Novakov et al., 2003, 048398), SO2 (Stern,
                 2005,190416), and various species (Dentener et al., 2006, 088434: Van Aardenne et al., 2001,
                 055564) are available in the literature; there are some similarities and some differences among
                 them, but the emission estimates for early times do not have the rigor of the studies for
                 present-day emissions. One major conclusion from all these studies is that the growth of
                 primary aerosol emissions in the 20th century was not nearly as rapid as the growth in CO2
                 emissions.  This is because in the late 19th and early 20th centuries, particle emissions such as
                 BC and POM were relatively high due to the heavy use of biofuels and the lack of particulate
                 controls on coal-burning facilities; however, as economic development continued, traditional
                 biofuel use remained fairly constant and particulate emissions from coal burning were reduced
                 by the application of technological controls (Bond et al., 2007, 190050). Thus, particle
                 emissions in the 20th century did not grow as fast as CO2  emissions, as the latter are roughly
                 proportional to total fuel use—oil and gas included. Another challenge is estimating historical
                 biomass burning emissions. A recent study suggested about a 40% increase in carbon
                 emissions from biomass burning from the beginning to the end of last century (Mouillot et al.,
                 2006,190549), but it is difficult to verify.
    Table 9-11.   Anthropogenic emissions of aerosols and precursors for 2000 and 1750.
    Source
    Biomass burning
    Biofuel
    Fossil fuel
    Species*
    BC
    POM
    S
    BC
    POM
    S
    BC
    POM
    S
    Emission*2000
    (Tg/yr)
    3.1
    34.7
    4.1
    9.1
    9.6
    3.0
    3.2
    98.9
    
    1.03
    12.8
    1.46
    0.39
    1.56
    0.12
    
    Emission 1750
    (Tg/yr)
    
    
    
    # Data source for 2000 emission: biomass burning - Global Fire Emission Dataset fGFED); biofuel BC and POM - Speciated Pollutant Emission Wzard (SPEW); biofuel sulfur - International Institute for
    Applied System Analysis (NASA); fossil fuel BC and POM - SPEW; fossil fuel sulfur - Emission Database for Global Atmospheric Research (EDGAR) and NASA. Fossil fuel emission of sulfur (S) is the sum of
    emission from industry, power plants, and transportation listed in Dentener et al. (2006, 088434V
    * S=sulfur, including S02 and particulate S0j2~. Most emitted as S02, and 2.5% emitted as S0j2~.
    
                                                                                    Source: Adapted from Dentener et al. (2006, 088434)
    
    
                      As an example, Table 9-11 shows estimated anthropogenic emissions of sulfur, BC and
                 POM in the present day (year 2000) and pre-industrial time (1750) compiled by Dentener et al.
                 (2006, 088434) These estimates have been used in the Aerosol Comparisons between
                 Observations and Models (AeroCom) project (Experiment B, which uses the year 2000
                 emission; and Experiment PP^E, which uses pre-industrial emissions), for simulating
                 atmospheric aerosols and anthropogenic aerosol RF. The AeroCom results are discussed below
                 and in Section 9.3.6.3.
    
    
           Aerosol Mass Loading and Optical Depth
    
                      In the global models, aerosols are usually simulated in the successive steps of sources
                 (emission and chemical formation), transport (from source location to other area), and removal
                 processes (dry deposition, in which particles fall onto the surface, and wet deposition by rain)
                 that control the aerosol lifetime. Collectively, emission, transport, and removal determine the
                 amount (mass) of aerosols in the atmosphere. Aerosol optical depth (AOD), which is a
                 measure of solar or thermal radiation being attenuated by aerosol particles via scattering or
                 absorption, can be related to the atmospheric aerosol mass loading as follows:
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                                                 AOD = MEE • M
                     where M is the aerosol mass loading per unit area (g m-2), MEE is the mass extinction
                 efficiency or specific extinction in unit of m2/g, which is
                                                 MEE =
                                                                                                        Equation 9-3
                     where Qext is the extinction coefficient (a function of particle size distribution and
                 refractive index), reff is the aerosol particle effective radius, p is the aerosol particle density,
                 and f is the ratio of ambient aerosol mass (wet) to dry aerosol mass M. Here, M is the result
                 from model-simulated atmospheric processes and MEE embodies the aerosol physical
                 (including microphysical) and optical properties. Since Qext varies with radiation wavelength,
                 so do MEE and AOD. AOD is the quantity that is most commonly obtained from remote
                 sensing measurements and is frequently used for model evaluation (see Chapter 2 of the CCSP
                 SAP2.3). AOD is also a key parameter determining aerosol radiative effects.
                     Here the results from the recent multiple global-model studies by the AeroCom project are
                 summarized, as they represent the current assessment of model-simulated atmospheric aerosol
                 loading, optical properties, and RF for the present-day. AeroCom aims to document differences
                 in global aerosol models and compare the model output to observations. Sixteen global models
                 participated in the AeroCom Experiment A (AeroCom-A), for which every model used their
                 own configuration, including their own choice of estimating emissions (Kinne et  al., 2006,
                 155903: Textor et al., 2006, 190456). Five major aerosol types: sulfate, BC, POM, dust, and
                 sea salt, were included in the experiments, although some models had additional aerosol
                 species. Of those major aerosol types, dust and sea-salt are predominantly natural in origin,
                 whereas sulfate, BC, and POM have major anthropogenic sources.
                     Table 9-12 summarizes the model results from the AeroCom-A for several key
                 parameters:  Sources (emission and chemical transformation), mass loading, lifetime, removal
                 rates, and MEE and AOD at a commonly used, mid-visible, wavelength of 550 nanometer
                 (nm). These are the globally averaged values for the year 2000. Major features and conclusions
                 are:
                     •   Globally, aerosol source (in mass) is dominated by sea salt, followed by dust, sulfate,
                         POM, and BC. Over the non-desert land area, human activity is the major source of
                         sulfate, black carbon, and organic aerosols.
                     •   Aerosols are removed from the atmosphere by wet and dry deposition. Although sea
                         salt dominates the emissions, it is quickly removed from the atmosphere because of
                         its large particle size and near-surface distributions, thus having the shortest lifetime.
                         The median lifetime of sea salt from the AeroCom-A models is less than half a day,
                         whereas dust and sulfate have similar lifetimes of 4 days and BC and POM 6-7 days.
                     •   Globally, small-particle-sized sulfate, BC, and POM make up a little over 10% of
                         total aerosol mass in the atmosphere. However, they are mainly from anthropogenic
                         activity, so the highest concentrations are in the most populated regions, where their
                         effects on climate and air quality are major concerns.
                     •   Sulfate and BC have their highest MEE at mid-visible wavelengths, whereas dust is
                         lowest among the aerosol types modeled. That means for the same amount of aerosol
                         mass, sulfate and BC are more effective at attenuating (scattering or absorbing) solar
                         radiation than dust. This is why the sulfate AOD is about the same as dust AOD even
                         though the atmospheric amount of sulfate mass is 10 times less than that of the dust.
                     •   There are large differences, or diversities, among the models for all the parameters
                         listed in Table 9-12. The largest  model diversity, shown as the % standard deviation
                         from the all-model-mean and the range (minimum and maximum values) in Table
                         9-12, is in sea salt emission and removal; this is mainly associated with the
                         differences in particle size range and source parameterizations in each model. The
                         diversity of sea salt atmospheric loading however is much smaller than that of
                         sources or sinks, because the largest particles have the shortest lifetimes even though
                         they comprise the largest fraction of emitted and deposited mass.
                                                                                                        Equation 9-4
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    Table 9-12.    Summary of statistics of AeroCom Experiment A results from 16 global models.
    Quantity
    Mean
    Median
    Range
    Stddev/mean*
    SOURCES (TG/YR)
    scV~
    BC
    Organic matter
    Dust
    Sea salt
    179
    11.9
    96.6
    1840
    16600
    186
    11.3
    96.0
    1640
    6280
    98-232
    7.8-19.4
    53-138
    672-4040
    2180-121000
    22%
    23%
    26%
    49%
    199%
    REMOVAL RATE (DAY-)
    scV~
    BC
    Organic matter
    Dust
    Sea salt
    0.25
    0.15
    0.16
    0.31
    5.07
    0.24
    0.15
    0.16
    0.25
    2.50
    0.19-0.39
    0.066-0.19
    0.09-0.23
    0.14-0.79
    0.95-35.0
    18%
    21%
    24%
    62%
    188%
    LIFETIME (DAY)
    S04"
    BC
    Organic matter
    Dust
    Sea salt
    4.12
    7.12
    6.54
    4.14
    0.48
    4.13
    6.54
    6.16
    4.04
    0.41
    2.6-5.4
    5.3-15
    4.3-11
    1.3-7.0
    0.03-1.1
    18%
    33%
    27%
    43%
    58%
    MASS LOADING (TG)
    S04"
    BC
    Organic matter
    Dust
    Sea salt
    1.99
    0.24
    1.70
    19.2
    7.52
    1.98
    0.21
    1.76
    20.5
    6.37
    0.92-2.70
    0.046-0.51
    0.46-2.56
    4.5-29.5
    2.5-13.2
    25%
    42%
    27%
    40%
    54%
    MEEAT550NM(M2G-1)
    SO/~
    BC
    Organic matter
    Dust
    Sea salt
    11.3
    9.4
    5.7
    0.99
    3.0
    9.5
    9.2
    5.7
    0.95
    3.1
    4.2-28.3
    5.3-18.9
    3.7-9.1
    0.46-2.05
    0.97-7.5
    56%
    36%
    26%
    45%
    55%
    AODAT550NM
    S04"
    BC
    Organic matter
    Dust
    Sea salt
    TOTAL AOT AT 550 NM
    0.035
    0.004
    0.018
    0.032
    0.033
    0.724
    0.034
    0.004
    0.019
    0.033
    0.030
    0.727
    0.015-0.051
    0.002-0.009
    0.006-0.030
    0.012-0.054
    0.02-0.067
    0.056-0.151
    33%
    46%
    36%
    44%
    42%
    18%
    Stddev/mean was used as the term "diversity" in Textor et al. (2006,190456).
    
    
    
                            Source: Textor et al. (2006,1904561 and Kinne et al. (2006,1559031, and AeroCom website http://nansen.ipsl.iussieu.fr/AEROCOM/data.html
    December 2009
    9-123
    

    -------
                     •   Among the key parameters compared in Table 9-12, the models agree best for
                         simulated total AOD - the % of standard deviation from the model mean is 18%,
                         with the extreme values just a factor of 2 apart. The median value of the multi-model
                         simulated global annual mean total AOD, 0.127, is also in agreement with the global
                         mean values from recent satellite measurements. However, despite the general
                         agreement in total AOD, there are significant diversities at the individual component
                         level for aerosol optical thickness, mass loading, and mass extinction efficiency. This
                         indicates that uncertainties in assessing aerosol climate forcing are still large, and
                         they depend not only on total AOD but also on aerosol absorption and scattering
                         direction (called asymmetry factor), both of which are determined by aerosol
                         physical and optical properties. In addition, even with large differences in mass
                         loading and MEE among different models, these terms could compensate for each
                         other (Equation 9-3) to produce similar AOD. This is illustrated in Figure 9-72. For
                         example, model LO and LS have quite different mass loading (44 and 74 mg m" ,
                         respectively), especially for dust and sea salt amount, but they produce nearly
                         identical total AOD (0.127 and 0.128, respectively).
                     •   Because of the large spatial and temporal variations of aerosol distributions, regional
                         and seasonal diversities are even larger than the diversity for global annual means.
    
                     To further isolate the impact of the differences in emissions on the diversity of simulated
                 aerosol mass loading, identical emissions for aerosols and their precursor were used in the
                 AeroCom Experiment B exercise in which 12 of the 16 AeroCom-A models participated
                 (Textor et al., 2007, 190458). The comparison of the results and diversity between AeroCom-A
                 and -B for the same models showed that using harmonized emissions does not significantly
                 reduce model diversity for the simulated global mass and AOD fields,  indicating that the
                 differences in atmospheric processes, such as transport, removal, chemistry, and aerosol
                 microphysics, play more important roles than emission in creating diversity among the models.
                 This outcome is somewhat different from another recent study, in which the differences in
                 calculated clear-sky aerosol RF between two models  (a regional model STEM and a global
                 model MOZART) were attributed mostly to the differences in emissions (Bates et al., 2006,
                 189912), although the conclusion was based on only two model simulations for a few focused
                 regions. It is highly recommended from the outcome  of AeroCom-A and -B that, although
                 more detailed evaluation for each individual process is needed, multi-model ensemble results,
                 e.g., median values of multi-model output variables, should be used to estimate aerosol RF,
                 due to their greater robustness, relative to individual models, when compared to observations
                 (Schulz et al., 2006, 190381: Textor et al., 2006, 190456: Textor et al., 2007, 190458).
    9.3.6.3.    Calculating Aerosol  Direct Radiative Forcing
                     The three parameters that define the aerosol direct RF are the AOD, the single scattering
                 albedo (SSA), and the asymmetry factor (g), all of which are wavelength dependent. AOD is
                 indicative of how much aerosol exists in the column, SSA is the fraction of radiation being
                 scattered versus the total attenuation (scattered and absorbed), and the g relates to the direction
                 of scattering that is related to the size of the particles (see Chapter 1 of the CCSP SAP2.3). An
                 indication of the particle size is provided by another parameter, the Angstrom exponent (A),
                 which is a measure of differences of AOD at different wavelengths. For typical tropospheric
                 aerosols, A tends to be inversely dependent on particle size; larger values of A are generally
                 associated with smaller aerosols particles. These parameters are further related; for example,
                 for a given composition, the ability of a particle to scatter radiation decreases more rapidly
                 with decreasing size than does its ability to absorb, so at a given wavelength varying A can
                 change SSA. Note that AOD, SSA, g, A, and all the other parameters in Equation 9-3 and
                 Equation 9-4 vary with space and time due to variations of both aerosol composition and
                 relative humidity, which influence these characteristics.
    December 2009                                        9-124
    

    -------
       n is
       0.1ft
    
     •  0,12
    I   fl-i
    "  0.08
    c  Q.Qi
    1  U.Q4
       D.02
         0
                       ll'l    •
                       Mill
    
                              I Hi
                              ,1         i
    •AH
     ss
     DU
    •POM
    •BC
    LO LS UL SP
    -------
    Table 9-13. S042" mass loading, MEE and AOD at 550 nm, shortwave radiative forcing at the top of
    the atmosphere, and normalized forcing with respect to AOD and mass. All values refer
    to anthropogenic perturbation.
    Model
    Mass load
    (mg m" )
    MEE
    (mV1)
    AOD att
    550 nm
    TOA Forcing
    (W/m2)
    Forcing/AOD
    (W/m2)
    Forcing/Mass
    (Wg-1)
    PUBLISHED SINCE IPCC 2001
    ACCM3
    B GEOSCHEM
    CGISS
    DGISS
    EGISS*
    FSPRINTARS
    GLMD
    HLOA
    I GATORG
    JPNNL
    KUIO-CTM
    LUIO-GCM
    2.23
    1.53
    3.30
    3.27
    2.12
    1.55
    2.76
    3.03
    3.06
    5.50
    1.79
    2.28
    
    11.8
    6.7
    
    
    9.7
    
    9.9
    
    7.6
    10.6
    
    
    0.018
    0.022
    
    
    0.015
    
    0.03
    
    0.042
    0.019
    
    -0.56
    -0.33
    -0.65
    -0.96
    -0.57
    -0.21
    -0.42
    -0.41
    -0.32
    -0.44
    -0.37
    -0.29
    
    -18
    -30
    
    
    
    
    -14
    
    -10
    -19
    
    -251
    -216
    -197
    -294
    -269
    -135
    -152
    -135
    -105
    -80
    -207
    -127
    AEROCOM: IDENTICAL EMISSIONS USED FOR YEAR 2000 AND 1750
    MUMI
    N UIO-CTM
    OLOA
    PLSCE
    Q ECHAMS-HAM
    R GISS**
    S UIO-GCM
    T SPRINTARS
    UULAQ
    Average A-L
    Average M-U
    Minimum A-U
    Maximum A-U
    StddevA-L
    Std dev M-U
    %Stddev/avgA-L
    %Stddev/avg M-U
    2.64
    1.70
    3.64
    3.01
    2.47
    1.34
    1.72
    1.19
    1.62
    2.70
    2.15
    1.19
    5.50
    1.09
    0.83
    40%
    39%
    7.6
    11.2
    9.6
    7.6
    6.5
    4.5
    7.0
    10.9
    12.3
    9.4
    8.6
    4.5
    12.3
    1.9
    2.6
    20%
    30%
    0.02
    0.019
    0.035
    0.023
    0.016
    0.006
    0.012
    0.013
    0.02
    0.024
    0.018
    0.006
    0.042
    0.010
    0.008
    41%
    45%
    -0.58
    -0.36
    -0.49
    -0.42
    -0.46
    -0.19
    -0.25
    -0.16
    -0.22
    -00.46
    -0.35
    -0.96
    -0.16
    0.202
    0.149
    44%
    43%
    -29
    -19
    -14
    -18
    -29
    -32
    -21
    -12
    -11
    -18
    -21
    -32
    -10
    7
    8
    38%
    37%
    -220
    -212
    -135
    -140
    -186
    -142
    -145
    -134
    -136
    -181
    -161
    -294
    -80
    68
    35
    385
    22%
    Model abbreviations: CCM3=Community Climate Model; GEOSCHEM=Goddard Earth Observing System-Chemistry; GISS=Goddard nstitute for Space Studies; SPRINTARS=Spectral Radiation-Transport
    Model for Aerosol Species; LMD=Laboratoire de Meteorologie Dynamique; LOA=Laboratoire d'OptiqueAtmospherique; GATORG=Gas, Aerosol Transport and General circulation model; PNNL=Pacific
    Northwest National Laboratory; UIO-CTM=Univeristy of Oslo CTM; UIO-GCM=University of Oslo GCM; UMI=University of Michigan; LSCE=Laboratoire des Sciences du Climat et de {'Environment;
    ECHAMS5-HAM=European Centre Hamburg with Hamburg Aerosol Module; ULAQ=University of IL'Aquila.
    
    
                                                                                           Source: Adapted from IPCC AR4 (2007, 0927651 and Schulz et al. (2006,1903811
    December 2009                                                           9-126
    

    -------
    Table 9-14.   Particulate organic matter (POM) and BC mass loading, AOD at 550 nm, shortwave
                 radiative forcing at the top of the atmosphere, and normalized forcing with respect to
                 AOD and mass.
    Model
    Mass
    load
    (mg rrf2)
    MEE
    (mV1)
    AOD at J
    CCQ nm Forcma
    ssunm (W/ 2j
    Forcing/
    AOD
    (W/m2)
    Forcing/
    Mass
    (Wg-1)
    Mass
    load
    (mg m"2)
    MEE
    (mV1)
    AOD at
    550 nm
    TOA
    Forcina
    (W/m2)
    Forcing/
    AOD
    (W/m2)
    Forcing/
    Mass
    (Wg-1)
    PUBLISHED SINCE IPCC 2001
    A SPRINTARS
    BLOA
    CGISS
    DGISS
    EGISS*
    FGISS
    G SPRINTARS
    H GATORG
    I MOZGN
    JCCM
    KUIO-CTM
    
    2.33
    1.86
    1.86
    2.39
    2.49
    2.67
    2.56
    3.03
    
    
    
    6.9
    9.1
    8.1
    
    
    10.9
    
    5.9
    
    
    -0.24
    0.016 -0.25
    0.017 -0.26
    0.015 -0.30
    -0.18
    -0.23
    0.029 -0.27
    -0.06
    0.018 -0.34
    
    
    
    -16
    -15
    -20
    
    
    -9
    
    -19
    
    
    -107
    -140
    -161
    -75
    -92
    -101
    -23
    -112
    
    
    
    
    0.37
    0.29
    0.29
    0.39
    0.43
    0.53
    0.39
    
    0.33
    0.30
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    0.36
    0.55
    0.61
    0.35
    0.50
    0.53
    0.42
    0.55
    
    0.34
    0.19
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    AEROCOM: IDENTICAL EMISSIONS FOR YEAR 2000 & 1750
    LUMI
    M UIO-CTM
    NLOA
    OLSCE
    P ECHAMS-HAM
    QGISS**
    R UIO-GCM
    S SPRINTARS
    TULAQ
    Average A-K
    Average L-T
    Minimum A-T
    Maximum A-T
    StddevA-K
    Std dev L-T
    %Stddev/avgA-K
    %Stddev/avg L-T
    1.16
    1.12
    1.41
    1.50
    1.00
    1.22
    0.88
    1.84
    1.71
    2.40
    1.32
    0.88
    3.03
    0.39
    0.32
    16%
    25%
    5.2
    5.2
    6.0
    5.3
    7.7
    4.9
    5.2
    10.9
    4.4
    8.2
    6.1
    4.4
    10.9
    1.7
    2.0
    21%
    33%
    0.0060 -0.23
    0.0058 -0.16
    0.0085 -0.16
    0.0079 -0.17
    0.0077 -0.10
    0.0060 -0.14
    0.0046 -0.06
    0.0200 -0.10
    0.0075 -0.09
    0.019 -0.24
    0.008 -0.13
    0.005 -0.34
    0.029 -0.06
    0.006 0.09
    0.005 0.05
    30% 36%
    56% 39%
    -38
    -28
    -19
    -22
    -13
    -23
    -13
    -5
    -12
    -16
    -19
    -38
    -5
    4
    10
    26%
    52%
    -198
    -143
    -113
    -113
    -100
    -115
    -68
    -54
    -53
    -102
    -106
    -198
    -23
    41
    46
    41%
    43%
    0.19
    0.19
    0.25
    0.25
    0.16
    0.24
    0.19
    0.37
    0.38
    0.37
    0.25
    0.16
    0.53
    0.08
    0.08
    22%
    32%
    6.8
    7.1
    7.9
    4.4
    7.7
    7.6
    10.3
    9.5
    7.6
    
    7.7
    4.4
    10.3
    
    1.6
    
    21%
    1.29
    1.34
    1.98
    1.11
    1.23
    1.83
    1.95
    3.50
    2.90
    
    1.90
    1.11
    3.50
    
    0.82
    
    43%
    0.25
    0.22
    0.32
    0.30
    0.20
    0.22
    0.36
    0.32
    0.08
    0.44
    0.25
    0.08
    0.61
    0.06
    0.09
    23%
    34%
    194
    164
    162
    270
    163
    120
    185
    91
    28
    
    153
    28
    270
    
    68
    
    45%
    1316
    1158
    1280
    1200
    1250
    917
    1895
    865
    211
    1242
    1121
    211
    2103
    384
    450
    31%
    40%
                                                          Source: Based on IPCC AR4 (2007, 092765) and Schulz et al. (2006,190381).
    December 2009
    9-127
    

    -------
                     The IPCC AR4 (2007, 092765) assessed anthropogenic aerosol RF based on the model
                 results published after the IPCC TAR in 2001, including those from the AeroCom study
                 discussed above. These results (adopted from IPCC AR4) are shown in Table 9-13 for sulfate
                 and Table 9-14 for carbonaceous aerosols (BC and POM), respectively. All values listed in
                 Table 9-13 and Table  9-14 refer to anthropogenic perturbation, i.e., excluding the natural
                 fraction of these aerosols. In addition to the mass burden, MEE, and AOD, Table 9-13 and
                 Table 9-14 also list the "normalized forcing", also known as "forcing efficiency", one for the
                 forcing per unit AOD, and the other the forcing per gram of aerosol mass (dry). For some
                 models, aerosols are externally mixed, that is, each aerosol particle contains only one aerosol
                 type such as sulfate, whereas other models allow aerosols to mix internally to different
                 degrees, that is, each aerosol particle can have more than one component,  such as black carbon
                 coated with sulfate. For models with internal mixing of aerosols, the component values for
                 AOD, MEE, and forcing  were extracted (Schulz et al, 2006, 190381).
                     Considerable variation exists among these models for all quantities in Table 9-13 and
                 Table 9-14. The  RF for all the components varies by a factor of 6 or more: Sulfate from 0.16 to
                 0.96 W/m2, POM from -0.06 to -0.34 W/m2, and BC from +0.08 to +0.61 W/m2,  with the
                 standard deviation in the  range of 30 to 40% of the ensemble mean. It should be noted that
                 although BC has the lowest mass loading and AOD, it is the only aerosol species that absorbs
                 strongly, causing positive forcing to warm the atmosphere, in contrast to other aerosols that
                 impose negative forcing to cool the atmosphere. As a result, the net anthropogenic aerosol
                 forcing as a whole becomes less negative when BC is included. The global average
                 anthropogenic aerosol direct RF at the top of the atmosphere (TOA) from  the models, together
                 with observation-based estimates (see Chapter 2 of the CCSP SAP2.3), is presented in Figure
                 9-73. Note the wide range for forcing in Figure 9-73. The comparison with observation-based
                 estimates shows that the model estimated forcing is in general lower, partially because the
                 forcing value from the model is the difference between present-day and pre-industrial time,
                 whereas the observation-derived quantity is the difference between an atmosphere with and
                 without anthropogenic aerosols, so the "background" value that is subtracted from the total
                 forcing is higher in the models. The discussion so far has dealt with global average values. The
                 geographic distributions of multi-model aerosol direct RF has been evaluated among the
                 AeroCom models, which are shown in Figure 9-74 for total and anthropogenic AOD at 550 nm
                 and anthropogenic aerosol RF at TOA, within the atmospheric  column, and at the surface.
                 Globally, anthropogenic AOD is about 25% of total AOD (Figure 9-74A and B) but is more
                 concentrated over polluted regions in Asia, Europe, and North America and biomass burning
                 regions in tropical southern Africa and South America. At TOA, anthropogenic aerosol causes
                 negative forcing over mid-latitude continents and oceans with the most negative values (-1 to
                 -2 W/m2) over polluted regions (Figure 9-74C). Although anthropogenic aerosol  has a cooling
                 effect at the surface with  surface forcing values down to -10 W/m  over China, India, and
                 tropical Africa (Figure 9-74E), it warms the atmospheric column with the largest effects again
                 over the polluted and  biomass burning regions. This heating effect will change the atmospheric
                 circulation and can affect the weather and precipitation (e.g., Kim et al., 2006, 190917).
    December 2009                                        9-128
    

    -------
                                             Aerosol Direct Radiative Forcing
                  §
                  11
                  %S
                  s
     Bellouinetal. (2005.155684)
     Chung etal. (2005,155733)
     Yuetal. (2006.156173)
                      GISSJ (Liao and Seinfeld, 2005,199892)
                      GISS_2 (Liao and Seinfeld, 2005,199892)
                      LOA (Reddy et al., 2005,190208)
                      SPRINTARS (Takemura et al., 2005,190439)
                      UIO-GCM (Kirkevag and Iversen, 2002,199893;
                      GATORG (Jacobson, 2001,043110)
                      GISS (Hansen et al., 2005,190596)
                      GISS (Koch. 2001.192054)
                      UMI
                      UIO_CTM
                      LOA
                      LSCE
                      ECHAM50HAM
                      GISS
                      UIO-GCM
                      SPRINTARS
                      ULAQ
                                                             -0.8
                                                     -0.6      -0.4      -0.2
                                                        Radiative Forcing (W/m2)
                                                                                                Source: IPCC (2007,092763.
    Figure 9-73.
    Aerosol direct radiative forcing in various climate and aerosol models.  Observed
    values are shown in the top section.
    December 2009
                                        9-129
    

    -------
                            A
                                                                     1
                                                                     I
                        •Hfml
                        5-0
                        4.0
                        .1.0
                        !.0
                        1 II
                        05
                        Pd
                        o.o
                        -0.2
                        -o.s
                        -1,0
                        -3.0
                        -J.O
                        -*n
                        -i.O
                        -10,0
                                              •45   8   45   M
                                                 loi^tulfi
                                Source: Schulz et al. (2006,1903811 and AeroCom image catalog (http://nansen.ipsl.iussieu.fr/AEROCOM/aerocomhome.htmll
    Figure 9-74.   Aerosol optical thickness and anthropogenic shortwave all-sky radiative forcing
                   from the AeroCom study. Shown in the figure: total AOD (A) and anthropogenic
                   AOD (B) at 550 nm, and radiative forcing at TOA (C), atmospheric column (D), and
                   surface (E).
    December 2009
    9-130
    

    -------
                                             Aerosol Direct Radiative Forcing
                    I
                    I
    Hadley (Jones etal., 2001,1Ł
    Hadley (Williams et al., 2001,199898)
    CSIRO (Rotstayn and Penner, 2001,193754)
    GISS (Menon et al., 2002,155978)
    CSIRO (Rotstayn and Liu, 2003,199905)
    LMDZ (Quaas et al., 2004,199907)
    LMDZ/POLDER (Dufresne et al, 2005,199908)
    GFDL (Ming et al, 2005,199919)
    ECHAM (Lohmann et al, 2000,199910)
    PNNL (Ghan et al, 2001,199911)
    NCAR-CCM (Chuang et al, 2002,199912)
    NCAR-CCM (Kristjansson et al, 2002,199916)
    SPRINTARS (Suzuki et al, 2004,199917)
    SPIRNTARS (Takemura et al, 2005,190439)
    GISS (Hansen et al, 2005,190596)
    LMDZ/CTRL (Quaas and Boucher, 2005,190573)
    LMDZ/POLDER (Quaas and Boucher, 2005,19057
    LMDZ/MODIS (Quaas and Boucher, 2005,190573)
    UM_ctrl(Chen and Penner. 2005.199918)
    UM-1 (Chen and Penner, 2005,199918)
    UM_2 (Chen and Penner, 2005,199918)
    UM_3 (Chen and Penner, 2005,199918)
    UM_4 (Chen and Penner, 2005,199918)
    UM_5 (Chen and Penner, 2005,199918)
    UM_6 (Chen and Penner, 2005,199918)
    Oslo (Penner et al, 2006,190564)
    LMDZ (Penner et al, 2006,190564)
    CCSR (Penner et al, 2006,190564)
                                                           -2.0       -1.5      -1.0      -0.5
                                                                     Radiative Forcing (W/m2)
                                                                                               Source: IPCC (2007, 092765).
    Figure 9-75.    Radiative forcing from the cloud albedo effect (1st aerosol indirect effect) in the
                     global climate models used from IPCC (2007, 092765). Chapter 2, Figure 2.14, of
                     the IPCC AR4. Species included in the  lower panel are S042", sea salt, organic
                     and BC, dust and nitrates; in the top panel, only S042", sea salt and OC are
                     included.
    December 2009
                                      9-131
    

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                     Basic conclusions from forward modeling of aerosol direct RF are:
                     •   The most recent estimate of all-sky shortwave aerosol direct RF at TOA from
                         anthropogenic sulfate, BC, and POM (mostly from fossil fuel/biofuel combustion and
                         biomass burning) is -0.22 ±0.18 W/m  averaged globally, exerting a net cooling
                         effect. This value would represent the low-end of the forcing magnitude, since some
                         potentially significant anthropogenic aerosols, such as nitrate and dust from human
                         activities are not included because of their highly uncertain sources and processes.
                         IPCC AR4 had adjusted the total anthropogenic aerosol direct RF to -0.5 ± 0.4 W/m2
                         by adding estimated anthropogenic nitrate and dust forcing values based on limited
                         modeling studies and by considering the observation-based estimates (see Chapter 2
                         of the CCSP SAP2.3).
                     •   Both sulfate and POM cause negative forcing whereas BC causes positive forcing
                         because of its highly absorbing nature. Although BC comprises only a small fraction
                         of anthropogenic aerosol mass load and AOD, its forcing efficiency (with respect to
                         either AOD  or mass) is an order of magnitude stronger than sulfate and POM, so its
                         positive shortwave forcing largely offsets the negative forcing from sulfate and
                         POM. This points out  the importance of improving the model ability to simulate each
                         individual aerosol components more accurately, especially black carbon. Separately,
                         it is estimated from recent model studies that anthropogenic sulfate, POM, and BC
                         forcings at TOA are -0.4, -0.18, +0.35 W/m2, respectively. The anthropogenic nitrate
                         and dust forcings are estimated at -0.1 W/m2 for each, with uncertainties exceeds
                         100% (IPCC, 2007, 092765).
                     •   In contrast to long-lived greenhouse gases, anthropogenic aerosol RF exhibits
                         significant regional and seasonal variations. The forcing magnitude is the largest over
                         the industrial and biomass burning source regions, where the  magnitude of the
                         negative aerosol forcing can be of the same magnitude or even stronger than that of
                         positive greenhouse gas forcing.
                     •   There is a large spread of model-calculated aerosol RF even in the global annual
                         averaged values. The AeroCom study shows that the model diversity at some
                         locations (mostly East Asia and African biomass burning regions) can reach ± 3
                         W/m2, which is an order of magnitude above the global averaged forcing value of -
                         0.22 W/m2. The large  diversity reflects the low level of current understanding of
                         aerosol radiative forcing, which is compounded by uncertainties in emissions,
                         transport, transformation, removal, particle size, and optical and microphysical
                         (including hygroscopic) properties.
                     •   In spite of the relatively small value of forcing at TOA, the magnitudes of
                         anthropogenic forcing at the surface and within the atmospheric column are
                         considerably larger: -1 to -2 W/m2 at the surface and +0.8 to +2 W/m2 in the
                         atmosphere. Anthropogenic aerosols thus cool the surface but heat the atmosphere,
                         on average. Regionally, the atmospheric heating can reach annually averaged values
                         exceeding 5 W/m2. Source: Schulz et al. (2006, 190381) and AeroCom Image
                         Catalog (littp://nansen.ipsl.jussieu.fr/AEROCOM7aerocomhome.html)
                     •   Figure 9-74D).  These  regional effects and the negative surface forcing are expected
                         to exert an important effect on climate through alteration of the hydrological cycle.
    
    
    
    9.3.6.4.    Calculating Aerosol  Indirect Forcing
    
    
           Aerosol Effects on Clouds
    
                     A subset of the aerosol particles can act as cloud condensation nuclei (CCN) and/or ice
                 nuclei (IN). Increases in aerosol particle concentrations, therefore, may increase the ambient
                 concentrations of CCN and IN,  affecting cloud properties. For a fixed cloud liquid water
                 content, a CCN increase will lead to more cloud droplets so that the cloud droplet size will
                 decrease. That effect leads to brighter clouds, the enhanced albedo then being referred to as the
                 "cloud albedo effect"  (Twomey, 1977, 190533), also known as the first indirect effect. If the
                 droplet size is smaller, it may take longer to rainout, leading to an increase in cloud lifetime,
                 hence the "cloud lifetime" effect (Albrecht,  1989, 045783), also called the second indirect
                 effect. Approximately one-third of the models used for the IPCC 20th century climate change
                 simulations incorporated an aerosol indirect effect, generally (though not exclusively)
                 considered only with sulfates.
                     Shown in Figure  9-75 are results from published model studies indicating the different RF
                 values from the cloud albedo effect. The cloud albedo effect ranges from -0.22 to -1.85 W/m2;
                 the lowest estimates are from simulations that constrained representation of aerosol effects on
                 clouds with satellite measurements of drop size vs. aerosol index. In view of the difficulty of
                 quantifying this effect remotely (discussed later), it is not clear whether this constraint
                 provides an improved estimate.  The estimate in the IPCC AR4  ranges from +0.4 to -1.1 W/m2,
                 with a "best-guess" estimate of  0.7 W/m2.
                     The representation of cloud effects in GCMs is considered below.  However, it is
                 becoming increasingly clear from studies based on high resolution simulations of aerosol-
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                 cloud interactions that there is a great deal of complexity that is unresolved in climate models.
                 This point is examined below (High Resolution Modeling).
                     Most models did not incorporate the "cloud lifetime effect." Hansen et al. (2005, 059087)
                 compared this latter influence (in the form of time-averaged cloud area or cloud cover
                 increase) with the cloud albedo effect. In contrast to the discussion in IPCC (2007, 092765),
                 they argue that the cloud cover effect is more likely to be the dominant one, as suggested both
                 by cloud-resolving model studies (Ackerman et al., 2004, 190056) and satellite observations
                 (Kaufman et al., 2005, 155891). The cloud albedo effect may be partly offset by reduced cloud
                 thickness accompanying aerosol pollutants, producing a meteorological (cloud) rather than
                 aerosol effect (see the discussion in Lohman and Feichter, 2005, 155942). The distinction
                 between meteorological feedback and aerosol forcing can become quite opaque; as noted
                 earlier, the term feedback is restricted here to those processes that are responding to a change
                 in temperature. Nevertheless, both aerosol indirect effects were utilized in Hansen et al. (2005,
                 059087), with the second indirect effect calculated by relating cloud cover to the aerosol
                 number concentration, which in turn is a function of sulfate, nitrate, black carbon and organic
                 carbon concentration. Only the low altitude cloud  influence was modeled, principally because
                 there are greater aerosol concentrations at low levels, and because low clouds currently exert
                 greater cloud RE The aerosol influence on high altitude clouds, associated with IN changes, is
                 a relatively unexplored area for models and as well for process-level understanding.
                     Hansen et al. (2005, 059087) used coefficients to normalize the cooling from aerosol
                 indirect effects to between -0.75 and -1 W/m2, based on comparisons of modeled and observed
                 changes in the diurnal temperature range as well as some satellite observations. The response
                 of the GISS model to the direct and two indirect effects is shown in Figure 9-76. As
                 parameterized, the cloud lifetime effect produced somewhat greater negative RF (cooling), but
                 this was the result of the coefficients chosen. Geographically, it appears that the "cloud cover"
                 effect produced slightly more cooling in the Southern Hemisphere than did the "cloud albedo"
                 response, with the reverse being true in the Northern Hemisphere (differences on the  order of a
                 few tenths °C).
    
    
           Model Experiments
    
                     There are many different factors that can explain the large divergence of aerosol indirect
                 effects in models (Figure  9-75). To explore this in more depth, Penner et al. (2006, 190564)
                 used three general circulation models to analyze the differences between models for the first
                 indirect effect, as well as a combined first plus second indirect effect. The models all  had
                 different cloud and/or convection parameterizations. In the first experiment, the monthly
                 average aerosol mass and size distribution of, effectively, sulfate aerosol were prescribed, and
                 all models followed the same prescription for parameterizing the cloud droplet number
                 concentration (CDNC) as a function of aerosol concentration. In that sense, the only difference
                 among the models was their separate cloud formation and radiation schemes. The  different
                 models all produced similar droplet effective radii, and therefore shortwave cloud forcing, and
                 change in net outgoing whole sky radiation between pre-industrial times and the present.
                 Hence the first indirect effect was not a strong function of the cloud or radiation scheme. The
                 results for this and the following experiments are presented in Figure 9-77, where the
                 experimental results are shown sequentially from left to right for the whole sky effect and in
                 Table 9-15 for the clear-sky and cloud forcing response as well.
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                                        Aerosol Direct and Indirect Effects
            Cloud Cover (%)          Planetary Al bedo (%)              Fs (W/mJ)                  ATs (°C)
      Direct                 .16                        .14  (E3 Run)              -.64  Direct (I E3 Run)       -.32
                                                                                -.77  AlECIdAlb (I Run)     -.36
     •5 -4 ,2 -I -.5-.2 .2 .51247   -2-! -.5-.2-.I .1 .2 .5 I  2   -23-5 -2 -I -.S-.2 .2 .5  I  1  5 19 -5-2 -I ..S-.2-.I.I .2  .5 I  2 S
    
                                                    Source: Reprinted with Permission of Bioresource Technology from Hansen et al. (2005, 0590871.
    Figure 9-76.   Anthropogenic impact on cloud cover, planetary albedo, radiative flux at the
                    surface (while holding sea surface temperatures and sea ice fixed) and  surface
                    air temperature change from the direct aerosol forcing (top row), the first indirect
                    effect (second row) and the  second indirect effect (third row).  The temperature
                    change is calculated from year 81-120 of a coupled atmosphere  simulation with
                    the GISS model.
    
                    The change in cloud forcing is the difference between whole sky and clear sky outgoing
                radiation in the present day minus pre-industrial simulation. The large differences seen
                between experiments 5 and 6 are due to the inclusion of the  clear sky component of aerosol
                scattering and absorption (the direct effect) in experiment 6.
                    In the second experiment, the aerosol mass and size distribution were again prescribed,
                but now each model used its  own formulation for relating aerosols to droplets. In this case one
                of the models produced larger effective radii and therefore a much smaller first indirect aerosol
                effect (Figure 9-77, Table 9-15. However, even in the two models where the effective radius
                change and net global forcing were similar, the spatial patterns of cloud forcing differ,
                especially over the biomass burning regions of Africa and South America.
                    The third experiment allowed the models to relate the change in droplet size to change in
                precipitation efficiency (i.e.,  they were now also allowing the second indirect effect - smaller
                droplets being less efficient rain producers - as well as the first). The models utilized the same
                relationship for autoconversion of cloud droplets to precipitation. Changing the precipitation
                efficiency results in all models producing an increase in cloud liquid water path, although the
                effect on cloud fraction was smaller than in the previous experiments. The net result was to
                increase the negative radiative forcing in all three models, albeit with different magnitudes: for
                two of the models the net impact on outgoing shortwave radiative increased by about 20%,
                whereas in the third model (which had the much smaller first indirect effect), it was magnified
                by a factor of three.
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                                 Exp I    Exp 2   6xp» 3   E*p -4    Exp 5   Exp 6
                                                                    Source: Adapted from Penner et al. (2006,1905641.
    Figure 9-77.   Global average present-day short wave cloud forcing at TOA (top) and change in
                  whole sky net outgoing shortwave radiation (bottom) between the present-day
                  and pre-industrial simulations for each model in each experiment.
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    Table 9-15.    Differences in present day and pre-industrial outgoing solar radiation (W/m2) in the
                    different experiments.
         Model
    EXP1
    EXP2
    EXP3
    EXP4
    EXP5
    EXP6
    WHOLE-SKY
     CAM-Oslo
                          -0.648
                                           -0.726
                                                            -0.833
                                                                             -0.580
                                                                                              -0.365
                                                                                                               -0.518
     LMD-Z
                          -0.682
                                           -0.597
                                                            -0.722
                                                                             -1.194
                                                                                              -1.479
                                                                                                               -1.553
     CCSR
                          -0.739
                                           -0.218
                                                            -0.733
                                                                             -0.350
                                                                                              -1.386
                                                                                                               -1.386
    CLEAR-SKY
     CAM-Oslo
                          -0.063
                                           -0.066
                                                            -0.026
                                                                             0.014
                                                                                              -0.054
                                                                                                               -0.575
     LMD-Z
                          -0.054
                                            0.019
                                                            0.030
                                                                             -0.066
                                                                                              -0.126
                                                                                                               -1.034
     CCSR
                           0.018
                                           -0.007
                                                            -0.045
                                                                             -0.008
                                                                                              0.018
                                                                                                               -1.160
    CLOUD-FORCING
     CAM-Oslo
                          -0.548
                                           -0.660
                                                            -0.807
                                                                             -0.595
                                                                                              -0.311
                                                                                                               0.056
     LMD-Z
                          -0.628
                                           -0.616
                                                            -0.752
                                                                             -1.128
                                                                                              -1.353
                                                                                                               -0.518
     CCSR
                          -0.757
                                           -0.212
                                                            -0.728
                                                                             -0.345
                                                                                              -1.404
                                                                                                               -0.200
    EXP1: tests cloud formation and radiation schemes
    EXP2: tests formulation for relating aerosols to droplets
    EXP3: tests inclusion of droplet size influence on precipitation efficiency
    EXP4: tests formulation of droplet size influence on precipitation efficiency
    EXP5: tests model aerosol formulation from common sources
    EXP6: added the direct aerosol effect
                                                                                       Source: Adapted from Penner et al. (2006,1905641.
                      In the fourth experiment, the models were now each allowed to use their own formulation
                 to relate aerosols to precipitation efficiency. This introduced some additional changes in the
                 whole sky shortwave forcing (Figure 9-77).
                      In the fifth experiment, models were allowed to produce their own aerosol concentrations,
                 but were given common sources. This produced the largest changes in the RF in several of the
                 models.  Within any one model, therefore, the change in aerosol concentration has the largest
                 effect on droplet concentrations and effective radii. This experiment too resulted in large
                 changes in RF.
                      In the last experiment, the aerosol direct effect was included, based on the full range of
                 aerosols used in each model. While the impact on the whole-sky forcing was not large, the
                 addition of aerosol scattering and absorption primarily affected the change in clear sky
                 radiation (Table 9-15).
                      The results of this study emphasize that in addition to questions concerning cloud physics,
                 the differences in aerosol concentrations among the models play a strong role in inducing
                 differences in the indirect effect(s), as well as the direct one.
                      Observational constraints on climate model simulations of the indirect effect with satellite
                 data (e.g., MODIS) have been performed previously in a number of studies (e.g., Lohmann et
                 al., 2006, 190451; Menon et al., 2008, 190534; Quaas et al., 2006, 190915; Storlevmo et al.,
                 2006, 190418).
                      These have been somewhat limited since the  satellite retrieved data used do not have the
                 vertical profiles needed to resolve aerosol and cloud fields (e.g., cloud droplet number and
                 liquid water content); the temporal resolution of simultaneous aerosol and cloud product
                 retrievals are usually not available  at a frequency of more than one a day; and higher level
                 clouds often obscure low clouds and aerosols. Thus, the indirect effect, especially the second
                 indirect effect, remains, to a large extent, unconstrained by satellite observations. However,
                 improved measurements of aerosol vertical distribution from the newer generation of sensors
                 on the A-train platform may provide a better understanding of changes to cloud properties
                 from aerosols. Simulating the top-of-atmosphere reflectance for comparison to satellite
                 measured values could be another way to compare model with observations, which would
                 eliminate the inconsistent assumptions of aerosol optical properties and surface reflectance
                 encountered when compared the model calculated and satellite retrieved AOD values.
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           Additional Aerosol Influences
    
                     Various observations have empirically related aerosols injected from biomass burning or
                 industrial processes to reductions in rainfall (e.g., Andreae et al, 2004, 155658: Eagan et al.,
                 1974, 190231; Rosenfeld, 2000, 002234; Warner, 1968, 157114). There are several potential
                 mechanisms associated with this response.
                     In addition to the two indirect aerosol effects noted above, a process denoted as the
                 "semidirect" effect involves the absorption of solar radiation by aerosols such as black carbon
                 and dust. The absorption increases the temperature, thus lowering the relative humidity and
                 producing evaporation, hence a reduction in cloud liquid water. The impact of this process
                 depends strongly on what the effective aerosol absorption actually is; the more absorbing the
                 aerosol, the larger the potential positive forcing on climate (by reducing low level clouds and
                 allowing more solar radiation to reach the surface). This effect is responsible for shifting the
                 critical value of SSA (separating aerosol cooling from aerosol warming) from 0.86 with fixed
                 clouds to 0.91 with varying clouds (Hansen et al., 1997, 043104). Reduction in cloud cover
                 and liquid water is one way aerosols could reduce rainfall.
                     More generally, aerosols can alter the location of solar radiation absorption within the
                 system, and this aspect alone can alter climate and precipitation even without producing any
                 change in net radiation at the top of the atmosphere (the usual metric for climate impact). By
                 decreasing solar absorption at the surface, aerosols (from both the direct and indirect effects)
                 reduce the energy available for evapotranspiration, potentially resulting in a decrease in
                 precipitation. This effect has been suggested as the reason for the decrease in pan evaporation
                 over the last 50 years (Roderick and Farquhar, 2002, 042788). The decline in solar radiation at
                 the surface appears to have ended in the 1990s (Wild et al., 2005, 156156), perhaps because of
                 reduced aerosol emissions in industrial areas (Kruger  and Grasl, 2002, 190200), although this
                 issue is still not settled.
                     Energy absorption by aerosols above the boundary layer can also inhibit precipitation by
                 warming the air at altitude relative to the surface, i.e., increasing atmospheric stability. The
                 increased stability can then inhibit convection, affecting both rainfall and atmospheric
                 circulation (Chung and Zhang, 2004, 190054; Ramanathan et al., 2001, 042681). To the extent
                 that aerosols decrease droplet size and reduce precipitation efficiency, this effect by itself could
                 result in lowered rainfall values locally.
                     In their latest simulations,  Hansen et al. (2007, 190597)  did find that the indirect aerosol
                 effect reduced tropical precipitation; however, the effect is similar regardless of which of the
                 two indirect effects is used, and also similar to the direct effect. So it is likely that the
                 reduction of tropical precipitation is because of aerosol induced cooling at the surface and the
                 consequent reduced evapotranspiration. Similar conclusions were reached by Yu et al. (2002,
                 190923) and Feingold et al. (2005, 190550). In this case, the  effect is a feedback and not a
                 forcing.
                     The local precipitation change, through its impacts on dynamics and soil moisture, can
                 have large positive feedbacks. Harvey (2004, 190598) concluded from assessing the response
                 to aerosols in eight coupled models that the aerosol impact on precipitation was larger than on
                 temperature. He also found that the precipitation impact differed substantially among the
                 models, with little correlation among them.
                     Recent GCM simulations have further examined the aerosol effects on hydrological cycle.
                 Ramanathan et al. (2005, 190199) showed from fully coupled ocean-atmosphere GCM
                 experiments that the "solar dimming" effect at the surface, i.e., the reduction of solar radiation
                 reaching the surface, due to the inclusion of absorbing aerosol forcing causes a reduction in
                 surface evaporation, a decrease in meridional sea surface temperature (SST) gradient and an
                 increase in atmospheric stability, and a reduction in rainfall over South Asia. Lau and Kim
                 (2006, 190226) examined the direct effects of aerosol on the  monsoon water cycle variability
                 from GCM simulations with prescribed realistic global aerosol forcing and proposed the
                 "elevated heat pump" effect, suggesting that atmospheric heating by  absorbing aerosols (dust
                 and black carbon), through water cycle feedback, may lead to a strengthening of the South
                 Asia monsoon. These model results are not necessarily at odds with each other, but rather
                 illustrate the complexity of the  aerosol-monsoon interactions that are associated with different
                 mechanisms, whose relative importance in affecting the monsoon may be strongly dependent
                 on spatial and temporal scales and the timing of the monsoon. These results may be model
                 dependent and should be further examined.
    
    
           High Resolution Modeling
    
                     Largely by its nature, the representation of the interaction between aerosol and clouds in
                 GCMs is poorly resolved. This  stems in large part from the fact that GCMs do not resolve
                 convection on their large grids (order of several hundred km), that their treatment of cloud
                 microphysics is rather crude, and that as discussed previously, their representation of aerosol
                 needs improvement. Superparametrization efforts (where standard cloud parameterizations in
                 the GCM are replaced by resolving clouds in each grid column of the GCM via a cloud
                 resolving model) (e.g.,Grabowski, 2004,  190590) could lead the way for the development of
                 more realistic cloud fields and thus improved treatments of aerosol cloud interactions in large-
                 scale models. However, these are just being incorporated in models that resolve both cloud and
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                 aerosols. Detailed cloud parcel models have been developed to focus on the droplet activation
                 problem (that asks under what conditions droplets actually start forming) and questions
                 associated with the first indirect effect. The coupling of aerosol and cloud modules to
                 dynamical models that resolve the large turbulent eddies associated with vertical motion and
                 clouds [large eddy simulations (LES) models, with grid sizes of—100 m and domains —10 km]
                 has proven to be a powerful tool for representing the details of aerosol-cloud interactions
                 together with feedbacks (e.g., Ackerman et al, 2004, 190056; Feingold et al, 1994, 190535;
                 1999, 190540: Kogan et al., 1994, 190186: Stevens et al.,  1996, 190417).
                      This section explores some of the complexity in the aerosol indirect effects revealed by
                 such studies to illustrate how difficult parameterizing these effects properly in GCMs could
                 really be.
    
    
           The First Indirect Effect
    
                     The relationship between aerosol and drop concentrations (or drop sizes) is a key piece of
                 the first indirect effect puzzle.  (It should not, however, be  equated to the first indirect effect
                 which concerns itself with the  resultant RF). A huge body of measurement and modeling  work
                 points to the fact that drop concentrations increase with increasing aerosol. The main
                 unresolved questions relate to the degree of this effect, and the relative importance of aerosol
                 size distribution, composition and updraft velocity in determining drop concentrations (for a
                 review, see Mcfiggans et al., 2006, 190532).  Studies indicate that the aerosol number
                 concentration and size distribution are the most important aerosol factors. Updraft velocity
                 (unresolved by GCMs) is particularly important under conditions of high aerosol particle
                 number concentration.
                     Although it is likely that composition has some effect on drop number concentrations,
                 composition is generally regarded as relatively unimportant compared to the other parameters
                 (Dusek et al., 2006, 155756: Ervens et al., 2005, 190527: Feingold et al., 2003, 190551:
                 Fitzgerald, 1975, 095417). Therefore, it has been stated that the significant complexity in
                 aerosol composition can be modeled, for the most  part, using fairly simple parameterizations
                 that reflect the soluble and insoluble fractions (e.g., Rissler et al.,  2004, 190225). However,
                 composition cannot be simply  dismissed. Furthermore, chemical interactions also cannot be
                 overlooked. A large uncertainty remains concerning the impact of organic species on cloud
                 droplet growth kinetics, thus cloud droplet formation. Cloud drop size is affected by wet
                 scavenging, which depends on aerosol composition especially for freshly emitted aerosol. And
                 future changes in composition will presumably arise due to biofuels/biomass burning and a
                 reduction in sulfate emissions, which emphasizes the need to include composition changes in
                 models when assessing the first indirect effect. The simple soluble/insoluble fraction model
                 may become less applicable than is currently the case.
                     The updraft velocity, and its change as climate warms, may be the most difficult aspect to
                 simulate in GCMs because of the small scales involved. In GCMs it is calculated in the
                 dynamics as a grid box average, and parameterized on the small scale indirectly because it is a
                 key part of convection and the spatial distribution of condensate, as well as droplet activation.
                 Numerous solutions to this problem have been sought, including estimation of vertical velocity
                 based on predicted turbulent kinetic energy from boundary layer models (Larson et al., 2001,
                 190212: Lohmann et al., 1999, 190443) and PDF representations of subgrid quantities, such as
                 vertical velocity and the vertically-integrated cloud liquid water ('liquid water path,' or LWP)
                 (Golaz et al., 2002, 190587: 2002, 190589: Larson et al., 2005,  190220: Pincus and Klein,
                 2000, 190565). Embedding cloud-resolving models within GCMs is also being actively
                 pursued (Grabowski et al., 1999, 190592: Randall  et al., 2003, 190201). Numerous other
                 details come into play; for example, the treatment of cloud droplet activation in GCM
                 frameworks is often based on the assumption of adiabatic  conditions, which may overestimate
                 the sensitivity of cloud to changes in CCN (Sotiropoulou et al.,  2006, 190406: Sotiropoulou et
                 al., 2007, 190405). This points to the need for improved theoretical understanding followed by
                 new parameterizations.
    
    
           Other Indirect Effects
    
                     The second indirect effect is often referred to  as the "cloud lifetime effect", based on the
                 premise that non-precipitating clouds will live longer. In GCMs the "lifetime effect" is
                 equivalent to changing the representation of precipitation production  and can be parameterized
                 as  an increase in cloud area or cloud cover (e.g., Hansen et al., 2005,  059087). The second
                 indirect effect hypothesis states that the more numerous and smaller drops associated with
                 aerosol perturbations, suppress collision-induced rain,  and result in a  longer cloud lifetime.
                 Observational evidence for the suppression of rain in warm clouds exists in the form of
                 isolated studies (e.g., Warner, 1968, 157114) but to date there is no statistically robust proof of
                 surface rain suppression (Levin and Cotton, 2008, 190375). Results from ship-track studies
                 show that cloud water may increase or decrease in the tracks (Coakley and Walsh, 2002,
                 192025) and satellite studies suggest similar results for warm boundary layer clouds (Han et
                 al., 2002, 049181). Ackerman et al. (2004, 190056) used LES to show that in stratocumulus,
                 cloud water may increase or decrease in response to increasing aerosol depending on the
                 relative humidify of the air overlaying the cloud. Wang et al. (2003, 157106) showed that all
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                 else being equal, polluted stratocumulus clouds tend to have lower water contents than clean
                 clouds because the small droplets associated with polluted clouds evaporate more readily and
                 induce an evaporation-entrainment feedback that dilutes the cloud. This result was confirmed
                 by Xue and Feingold (2006, 190920) and Jiang and Feingold (2006, 190976) for shallow
                 cumulus, where pollution particles were shown to decrease cloud fraction. Furthermore, Xue et
                 al. (2008, 190921) suggested that there may exist two regimes: the first, a precipitating regime
                 at low aerosol concentrations where an increase in aerosol will suppress precipitation and
                 increase cloud cover (Albrecht, 1989, 045783): and a second, non-precipitating regime where
                 the enhanced evaporation associated with smaller drops will decrease cloud water and cloud
                 fraction.
                     The possibility of bistable aerosol states was proposed earlier by Baker and Charlson
                 (1990, 190016) based on consideration of aerosol sources and sinks. They used a simple
                 numerical model to suggest that the marine boundary layer prefers two aerosol states: a clean,
                 oceanic regime characterized by a weak aerosol source and less reflective clouds; and a
                 polluted, continental regime characterized by more reflective clouds. On the other hand, study
                 by Ackerman et al. (1994, 189975) did not support such a bistable system using a somewhat
                 more sophisticated model. Further observations are needed to clarify the nature of
                 cloud/aerosol interactions under a variety of conditions.
                     Finally, the question of possible effects of aerosol on cloud lifetime was examined by
                 Jiang et al. (2006, 133165), who tracked hundreds of cumulus clouds generated by LES from
                 their formative stages until they dissipated.  They showed that in the model there was no effect
                 of aerosol on cloud lifetime, and that cloud lifetime was dominated by dynamical variability.
                     It could be argued that the representation of these complex feedbacks in GCMs is not
                 warranted until a better understanding of the processes is at hand. Moreover, until GCMs are
                 able to represent cloud scales, it is questionable what can be obtained by adding microphysical
                 complexity to poorly resolved clouds. A better representation of aerosol-cloud interactions in
                 GCMs therefore depends on the ability to improve representation of aerosols and clouds, as
                 well as their interaction, in the hydrologic cycle. This issue is discussed further in the next
                 chapter.
    
    
    
    9.3.6.5.    Aerosol in the Climate Models
    
    
           Aerosol in the IPCC AR4 Climate  Model Simulations
    
                     To assess the atmospheric and climate response to aerosol forcing, e.g., changes in surface
                 temperate, precipitation, or  atmospheric circulation, aerosols, together with greenhouse gases
                 should be an integrated part of climate model simulation under the past, present, and future
                 conditions. Table 9-16 lists  the forcing species that were included in 25 climate modeling
                 groups used in the IPCC AR4 (2007, 092765) assessment. All the models included long-lived
                 greenhouse gases, most models included sulfate direct forcing, but only a fraction of those
                 climate models considered other aerosol types. In other words, aerosol RF was not adequately
                 accounted for in the climate simulations for the IPCC AR4. Put still differently, the current
                 aerosol modeling capability has not been fully incorporated into the climate model
                 simulations. As pointed out in Section 9.3.6.4, fewer than one-third of the models incorporated
                 an aerosol indirect effect, and most considered only sulfates.
                     The following discussion compares two of the IPCC AR4 climate models that include all
                 major forcing agencies in their climate simulation: the model from the NASA Goddard
                 Institute for Space Studies (GISS) and from the NOAA Geophysical Fluid Dynamics
                 Laboratory (GFDL). The purpose in presenting these comparisons is to help elucidate how
                 modelers go about assessing their aerosol components, and the difficulties that entail. A
                 particular concern is how aerosol forcings were obtained in the climate model experiments for
                 IPCC AR4. Comparisons with observations have already led to some improvements that can
                 be implemented in climate models for subsequent climate change experiments (e.g., Koch et
                 al., 2006, 190184, for GISS model). This aspect is discussed further in Chapter 4 of the CCSP
                 SAP2.3.
    December 2009                                        9-139
    

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    Table 9-16. Forcings used in IPCC
    adapted from SAP 1.1
    participating modelini
    documentation/ipcc
    AR4 simulations of 20th century climate change. This table is
    Table 5.2 (compiled using information provided by the
    3 centers, see http://www.pcmdi.llnl.gov/ipcc/model-
    model documentation. php) plus additional information from
    that website. Eleven different forcings are listed: well-mixed greenhouse gases (G),
    tropospheric and stratospheric ozone (0), S042" aerosol direct (SD) and indirect
    effects (S), black carbon (BC) and organic carbon aerosols (OC), mineral dust (MD),
    sea salt (SS), land use/land cover (LU), solar irradiance (SO), and volcanic aerosols
    (V). Check mark denotes inclusion of a specific forcing. As used here, "inclusion"
    means specification of a time-varying forcing, with changes on interannual and
    longer timescales.
    
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    Model
    BCC-CMI
    BCCR-BCM2.0
    CCSM3
    CGCM3.1(T47)
    CGCM3.1(T63)
    CNRM-CM3
    CSIRO-MkS.O
    CSIRO-Mk3.5
    ECHAMS/MPI-OM
    ECHO-G
    FGOALS-g1 .0
    GFDL-CM2.0
    GFDL-CM2.1
    GISS-AOM
    GISS-EH
    GISS-ER
    INGV-SXG
    INM-CM3.0
    IPSL-CM4
    MICROC3.2(hires)
    MICROC3.2(medres)
    MRI-CGCM2.3.2
    PCM
    UKMO-HasCM3
    UKMO-HadGEM1
    Country
    China
    Norway
    USA
    Canada
    Canada
    France
    Australia
    Australia
    Germany
    Germany/
    Korea
    China
    USA
    USA
    USA
    USA
    USA
    Italy
    Russia
    France
    Japan
    Japan
    Japan
    USA
    U.K.
    U.K.
    G
    A/
    A/
    A/
    V
    V
    V
    V
    V
    V
    A/
    V
    V
    A/
    V
    V
    V
    A/
    V
    A/
    V
    V
    V
    V
    AI
    V
    0 SD SI BC OC MD SS LU SO V
    V V
    A/ A/ A/
    V V V V V V
    V
    V
    V V V
    V
    V
    V V V
    V V V V V
    V
    V V V V V V
    A/ A/ A/ A/ A/ A/
    A/ A/
    //////////
    AA'A'A'A'A'A'A'A'A'
    / / / / / / / / / /
    AA'A'A'A'A'A'A'A'A'
    V V
    A/ A/
    A/ A/
    V V V V V V V V V
    V V V V V V V V V
    V V V
    V V V V
    A/ A/ A/
    A/ V V V V V V
           77?e G/SS Mode/
    
                     There have been many different configurations of aerosol simulations in the GISS model
                 over the years, with different emissions, physics packages, etc., as is apparent from the
                 multiple GISS entries in the preceding figures and tables. There were also three different GISS
                 GCM submissions to IPCC AR4, which varied in their model physics and ocean formulation.
                     (Note that the aerosols in these three GISS versions are different from those in the
                 AeroCom simulations described in Sections 9.3.6.2 and 9.3.6.3.) The GCM results discussed
    December 2009
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                 below all relate to the simulations known as GISS model ER (Schmidt et al, 2006, 190373)
                 (see Table 9-16). Although the detailed description and model evaluation have been presented
                 in Liu et al.  (2006, 190422), below are the general characteristics of aerosols in the GISS ER:
                     Aerosol fields: The aerosol fields used in the GISS ER is  a prescribed "climatology"
                 which is obtained from chemistry transport model simulations with monthly averaged mass
                 concentrations representing conditions up to 1990. Aerosol species included are sulfate, nitrate,
                 BC, POM, dust, and sea salt. Dry size effective radii are specified for each of the aerosol types,
                 and laboratory-measured phase functions are employed for all solar and thermal wavelengths.
                 For hygroscopic aerosols (sulfate, nitrate, POM, and sea salt),  formulas are used for the
                 particle growth of each aerosol as a function of relative humidity, including the change in
                 density and  optical parameters. With these specifications, the AOD, single scattering albedo,
                 and phase function of the various aerosols are calculated. While the aerosol distribution is
                 prescribed as monthly mean values, the relative humidity component of the extinction is
                 updated each hour. The global averaged AOD at 550 nm is about  0.15.
                     Global  distribution: When comparing with AOD from observations by multiple satellite
                 sensors of MODIS, MISR, POLDER, and AVHRR and surface based sunphotometer network
                 AERONET  (see Chapter 2 of the CCSP SAP2.3 for detailed information about data),
                 qualitative agreement is apparent, with generally higher burdens in Northern Hemisphere
                 summer, and seasonal variations of smoke over southern Africa and South America, as well as
                 wind blown dust over northern African and the Persian Gulf. Aerosol optical depth in both
                 model and observations is  smaller away from land. There are,  however, considerable
                 discrepancies between the  model and observations. Overall, the GISS GCM has reduced
                 aerosol optical depths compared with the satellite data (a global, clear-sky average of about
                 80% compared with MODIS and MISR data), although it is in better agreement with
                 AERONET  ground-based  measurements in some locations (note that the input aerosol values
                 were calibrated with AERONET data). The model values over the Sahel in Northern
                 Hemisphere winter and the Amazon in Southern Hemisphere winter are excessive, indicative
                 of errors in the biomass burning distributions, at least partially associated with an older
                 biomass burning source used (the source used here was from (Liousse et al., 1996, 078158)).
                     Seasonal variation: A comparison of the seasonal distribution of the global AOD between
                 the GISS model and satellite data indicates that the model seasonal variation is in qualitative
                 agreement with observations for many of the locations that represent major aerosol regimes,
                 although there are noticeable differences. For example, in some locations the seasonal
                 variations are different from or even opposite to the observations.
                     Particle size parameter: The Angstrom exponent (A), which is determined by the contrast
                 between the AOD at two or more different wavelengths and is related to aerosol particle size
                 (discussed in Section 9.3.6.3). This parameter is important because the particle size
                 distribution  affects the efficiency of scattering of both short and long wave radiation, as
                 discussed earlier. A from the GISS model is biased low compared with AERONET, MODIS,
                 and POLDER data, although there are technical differences in determining the A. This low
                 bias suggests that the aerosol particle size in the GISS model is probably too large. The
                 average effective radius in the GISS model appears to be 0.3-0.4 um, whereas the
                 observational data indicates a value more in the range of 0.2-0.3 um (Liu et al., 2006, 190422).
                     Single scattering albedo: The model-calculated SSA (at 550 nm) appears to be generally
                 higher than the AERONET data at worldwide locations (not enough absorption),  but lower
                 than AERONET data in Northern Africa, the Persian Gulf, and the Amazon (too much
                 absorption). This discrepancy reflects the difficulties in modeling BC, which is the dominant
                 absorbing aerosol, and aerosol sizes. Global averaged SSA at 550 nm from the GISS model is
                 at about 0.95.
                     Aerosol direct RF: The GISS model calculated anthropogenic aerosol direct shortwave RF
                 is -0.56 W/m2 at TOA and  -2.87 W/m2 at the surface.  The TOA forcing (upper left, Figure
                 9-78) indicates that, as expected, the model has larger negative values in polluted regions and
                 positive forcing at the highest latitudes. At the surface (lower left, Figure 9-78) GISS model
                 values exceed -4 W/m over large regions. Note there is also a longwave RF of aerosols (right
                 column), although they are much weaker than the shortwave RF.
                     There are several concerns  for climate change simulations related to the aerosol trend in
                 the GISS model. One  is that the aerosol fields in the GISS AR4 climate simulation (version
                 ER) are kept fixed after 1990. In fact, the observed trend shows a reduction in tropospheric
                 aerosol optical thickness from 1990 through the present, at least over the oceans (Mishchenko
                 and Geogdzhayev, 2007, 190545). Hansen et al. (2007, 190597) suggested that the deficient
                 warming in the GISS model over Eurasia post-1990 was due to the lack of this trend. Indeed, a
                 possible conclusion from the Penner et al. (2002, 190562) study was that the GISS model
                 overestimated the AOD (presumably associated with anthropogenic aerosols) poleward of
                 30°N. However, when an alternate experiment reduced the aerosol optical depths, the polar
                 warming became excessive (Hansen et al., 2007, 190597). The other concern is that the GISS
                 model may underestimate  the organic and sea salt AOD, and overestimate the influence of
                 black carbon aerosols in the biomass burning regions (Liu et al., 2006, 190422; deduced from
                 Penner et al., 2002, 190562). To the extent that is true, it would indicate the GISS model
                 underestimates the aerosol direct cooling effect in a substantial portion of the tropics, outside
                 of biomass burning areas.  Clarifying those issues requires numerous modeling experiments
                 and various  types of observations.
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           The GFDL Model
    
                     A comprehensive description and evaluation of the GFDL aerosol simulation are given in
                 Ginoux et al. (2006, 190582). Below are the general characteristics:
                     Aerosol fields: The aerosols used in the GFDL climate experiments are obtained from
                 simulations performed with the MOZART 2 model (Model for Ozone and Related chemical
                 Tracers) (Horowitz, 2006, 190620; Horowitz et al., 2003, 057770). The exceptions were dust,
                 which was generated with a separate simulation of MOZART 2, using sources from Ginoux et
                 al. (2001, 190579) and wind fields from NCEP/NCAR reanalysis data; and sea salt, whose
                 monthly mean concentrations were obtained from a previous study by Haywood et al. (1999,
                 040453). It includes most of the same aerosol species as in the GISS model (although it does
                 not include nitrates), and, as in the GISS model, relates the dry aerosol to wet aerosol optical
                 depth via the model's relative humidity for sulfate (but not for organic carbon); for sea salt, a
                 constant relative humidity of 80% was used. Although the parameterizations come from
                 different sources, both models maintain a very large growth in sulfate particle size when the
                 relative humidity exceeds 90%.
                     Global distributions: Overall, the GFDL global mean aerosol mass loading is within 30%
                 of that of other studies (Chin et al., 2002, 189996; Reddy et al., 2005, 190207; Tie et al., 2005,
                 190459), except for sea salt, which is 2 to 5 times smaller. However, the sulfate AOD (0.1) is
                 2.5 times that of other studies, whereas the organic carbon value is considerably smaller (on
                 the order of 1/2). Both of these differences are influenced by the relationship with relative
                 humidity. In the GFDL model, sulfate is allowed to grow up to 100% relative humidity, but
                 organic carbon does not increase in size as relative humidify increases. Comparison of AOD
                 with AVHRR and MODIS data for the time period 1996-2000 shows that the global mean
                 value over the ocean (0.15)  agrees with AVHRR data (0.14) but there are significant
                 differences regionally, with  the model overestimating the value in the northern mid latitude
                 oceans and underestimating it in the southern ocean. Comparison with MODIS also shows
                 good agreement globally (0.15), but in this case indicates large disagreements over land, with
                 the model producing excessive AOD over industrialized countries and underestimating the
                 effect over biomass burning regions.  Overall, the global averaged AOD at 550 nm is 0.17,
                 which is higher than the maximum values in the AeroCom-A experiments (Table 9-12) and
                 exceeds the observed value too (Ae and S* in Figure 9-72).
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       net totor TOA
      -56
                                                 JS7
       netsdar BOA
    -1.87
    net thermal BOA
    .13
                                                                    -J   -.2   -J   0    .1    3    ,5    .7   I.I
    
                                                                                    Source: Figure provided by A. Lads, GISS.
    Figure 9-78.   Direct radiative forcing by anthropogenic aerosols in the GISS model (including
                    sulfates, BC, OC and nitrates).  Short wave forcing at TOA and surface are shown
                    in the top left and bottom left panels. The corresponding thermal forcing is
                    indicated in the right hand panels.
    
                    Composition: Comparison of GFDL modeled species with in situ data over North
                America, Europe, and over oceans has revealed that the sulfate is overestimated in spring and
                summer and underestimated in winter in many regions, including Europe and North America.
                Organic and black carbon aerosols are also overestimated in polluted regions by a factor of
                two, whereas organic carbon aerosols are elsewhere underestimated by factors of 2 to 3. Dust
                concentrations at the surface agree with observations to within a factor of 1 in most places
                where significant dust exists, although over the southwest U.S. it is a factor of 10 too large.
                Surface concentrations of sea salt are underestimated by more than a factor of 2. Over the
                oceans, the excessive sulfate AOD compensates for the low sea salt values except in the
                southern oceans.
                    Size and single-scattering albedo: No specific comparison was given for particle size or
                single-scattering albedo, but the excessive sulfate would likely produce too high a value of
                reflectivity relative to absorption except in some polluted regions where black carbon (an
                absorbing aerosol) is also overestimated.
                    As in the case of the GISS  model, there are several concerns with the GFDL model. The
                good global-average agreement masks an excessive aerosol loading over the Northern
                Hemisphere (in particular, over the northeast U.S. and Europe) and an underestimate over
                biomass burning regions and the southern oceans. Several model improvements are needed,
                including better parameterization of hygroscopic growth at high relative humidity for sulfate
                and organic carbon; better sea salt simulations; correcting an error in extinction coefficients;
                and improved biomass burning  emissions inventory (Ginoux et al., 2006, 190582).
    
    
    
           Comparisons between GISS and GFDL Model
    
                    Both GISS and GFDL models were used in the IPCC AR4 climate  simulations for climate
                sensitivity that included aerosol forcing. It would be constructive, therefore, to compare the
                similarities and differences of aerosols in these two models and to understand what their
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                impacts are in climate change simulations. Figure 9-79 shows the percentage AOD from
                different aerosol components in the two models.
                     Sulfate: The sulfate AOD from the GISS model is within the range of that from all other
                models (Table 9-13), but that from the GFDL model exceeds the maximum value by a factor of
                2.5. An assessment in SAP 3.2 (CCSP, 2008, 192028; Shindell et al, 2008, 190393) also
                concludes that GFDL had excessive sulfate AOD compared with other models. The sulfate
                AOD from GFDL is nearly a factor of 4 large than that from GISS, although the sulfate burden
                differs only by about 50% between the two models. Clearly, this implies a large difference in
                sulfate MEE between the two models.
                     BC and POM: Compared to observations, the GISS model appears to overestimate the
                influence of BC and POM in the biomass burning regions and underestimate it elsewhere,
                whereas the GFDL model is somewhat the reverse: it overestimates it in polluted regions, and
                underestimates it in biomass burning  areas. The global comparison shown in Table 9-14
                indicates the GISS model has values similar to those from other models, which might be the
                result of such compensating errors. The GISS and GFDL models have relatively similar
                global-average black carbon contributions, and the same appears true for POM.
                     Sea salt: The GISS model has a much larger sea salt contribution than does GFDL (or
                indeed other models).
                     Global and regional distributions: Overall, the global averaged AOD is 0.15 from the
                GISS model and 0.17 from GFDL. However, as shown in Figure 9-79, the contribution to this
                AOD from different aerosol components shows greater disparity. For example, over the
                Southern Ocean where the primary influence is due to sea salt in the GISS model, but in the
                GFDL it is sulfate. The lack of satellite observations of the component contributions and the
                limited available in situ measurements make the model improvements at aerosol composition
                level difficult.
                     Climate simulations: With such large differences in aerosol composition and distribution
                between the GISS and GFDL models, one might expect that the model simulated surface
                temperature might be quite different.  Indeed, the GFDL model was able to reproduce the
                observed temperature change during the 20th century without the use of an indirect aerosol
                effect, whereas the GISS model required a substantial indirect aerosol contribution (more than
                half of the total aerosol forcing) (Hansen et al., 2007, 190597). It is likely that the reason for
                this difference was the excessive direct effect in the GFDL model caused by its overestimation
                of the sulfate optical depth. The GISS model direct aerosol effect (see Section 9.3.6.6) is close
                to that derived from observations (Chapter 2 of the CCSP SAP2.3); this suggests that for
                models with climate sensitivity close  to 0.75°C/(W/m2) (as in the GISS and GFDL models), an
                indirect effect is needed.
    December 2009                                        9-144
    

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                                                  nun=U96  BC ADD Fraction  imix=l96
                                                        ire Siff ADD Fr?r:t.~>n
                                             18 61   mui-OBt OunAUD hnsmon  m»x*90.7
                                                  180  IJdW ftM  0  60E  ilDE  180
                  Figure 9-79. Percentage of aerosol optical depth in the GISS, left, based on Liu et
                  al. (2006,190422). provided by A. Lacis, GISS, and GFDL, right, from Ginoux et al.
                  (2006,190582).  Models associated with the different components: S(>42~ (1st
                  row), BC (2nd row), OC (3rd row), sea-salt (4th row), dust (5th row), and nitrate
                  (last row). Nitrate not available in GFDL model). Numbers on the GISS panels are
                  global average, but on the GFDL panels are maximum and minimum.
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           Additional Considerations
    
                     Long wave aerosol forcing: So far only the aerosol RF in the shortwave (solar) spectrum
                 has been discussed. Figure 9-78 (right column) shows that compared to the shortwave forcing,
                 the values of anthropogenic aerosol long wave (thermal) forcing in the GISS model are on the
                 order of 10%. Like the shortwave forcing, these values will also be affected by the particular
                 aerosol characteristics used in the simulation.
                     Aerosol vertical distribution: Vertical distribution is particularly important for absorbing
                 aerosols, such as BC and dust in calculating the RF, particularly when longwave forcing is
                 considered (e.g., Figure 9-78) because the energy they reradiate depends on the temperature
                 (and hence altitude), which affects the calculated forcing values. Several model inter-
                 comparison studies have shown that the largest difference among model simulated aerosol
                 distributions is the vertical profile (e.g., Lohmann et al., 2001, 190448; Penner et al., 2002,
                 190562: Textor et al., 2006, 190456X  due to the significant diversities in atmospheric
                 processes in the models (e.g., Table 9-12). In addition, the vertical distribution also varies with
                 space and time, as illustrated in Figure 9-80 from the GISS ER simulations for January and
                 July showing the most probable altitude of aerosol vertical locations. In general, aerosols in the
                 northern hemisphere are located at lower altitudes in January than in July, and vice versa for
                 the southern hemisphere.
                     Mixing state: Most climate model simulations incorporating different aerosol types have
                 been made using external mixtures, i.e., the evaluation of the aerosols and their radiative
                 properties are calculated separately for each aerosol type (assuming no mixing between
                 different components within individual particles). Observations indicate that aerosols
                 commonly consist of internally mixed particles, and these "internal mixtures" can have very
                 different radiative impacts. For example, the GISS-1 (internal mixture) and GISS-2 (external
                 mixture) model results shows very different magnitude and sign of aerosol forcing from
                 slightly positive (implying slight warming) to strong negative (implying significant cooling)
                 TOA forcing (Figure 9-73), due to changes in both radiative properties of the mixtures, and in
                 aerosol amount. The more sophisticated aerosol mixtures from detailed microphysics
                 calculations now being used/developed by different modeling groups may well end up
                 producing very different direct (and indirect) forcing values.
                     Cloudy sky vs. clear  sky: The satellite or AERONET observations are all for clear sky
                 only because aerosol cannot be measured in the remote sensing technique when clouds are
                 present.  However, almost all the model results are for all-sky because of difficulty  in extracting
                 cloud-free scenes from the GCMs. So the AOD comparisons discussed earlier are not
                 completely consistent. Because AOD  can be significantly amplified when relative humidity is
                 high, such as near or inside clouds, all-sky AOD values are expected to be higher than clear
                 sky AOD values. On the other hand, the aerosol RF  at TOA is significantly lower for all-sky
                 than for clear sky conditions; the IPCC AR4 and AeroCom RF study (Schulz et al., 2006,
                 190381) have shown that  on average the aerosol RF value for all-sky is about 1/3 of that for
                 clear sky although with large diversity (63%). These aspects illustrate the  complexity of the
                 system and the difficulty of representing aerosol radiative influences in climate models whose
                 cloud and aerosol distributions are somewhat problematic. And of course aerosols in cloudy
                 regions can affect the clouds themselves, as  discussed in Section 9.3.6.5.
    December 2009                                         9-146
    

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                                     •
                1
                         100   JAC  410  480 540  400 660  72C  780  640  900
                                                                                            Source: A. Lacis, GISS.
    Figure 9-80.    Most probable aerosol altitude (in pressure, hPa) from the GISS model in January
                    (top) and July (bottom).
    9.3.6.6.   Impacts of Aerosols on Climate Model Simulations
    
    
          Surface Temperature Change
    
                   It was noted in the introduction that aerosol cooling is essential in order for models to
                produce the observed global temperature rise over the last century, at least models with climate
                sensitivities in the range of 3°C for doubled CO2 (or ~0.75°C/(W/m2)). The implications of
                this are discussed here in somewhat more detail. Hansen et al. (2007, 190597) show that in the
                GISS model, well-mixed greenhouse gases produce a warming of close to 1°C between 1880
                and the present (Table 9-17). The direct effect of tropospheric aerosols as calculated in that
                model produces cooling of close to -0.3°C between those same years, while the indirect effect
                (represented in that study as cloud cover change) produces an additional cooling of similar
                magnitude (note that the general model result quoted in IPCC AR4 is that the indirect RF is
                twice that of the direct effect).
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    Table 9-17.    Climate forcings (1880-2003) used to drive GISS climate simulations, along with the
                    surface air temperature changes obtained for several periods.
    
               Forcing Agent                     Forcing Wm"2 (1880-2003)                  AT Surface °C (year to 2003)
                                                Fa         Fs         Fe        1880      1900       1950       1979
    Well-mixed GHGs                     2.62       2.50        2.65       2.72       0.96       0.93        0.74       0.43
    
    Stratospheric H20                                          0.06       0.05       0.03       0.01        0.05       0.00
    
    03                                0.44       0.28        0.26       0.23       O.pOS      0.05        0.00       -0.01
    
    Land use                                                -0.09       -0.09       -0.05      -O.p07      -0.04       -0.02
    
    Snow albedo                        0.05       0.05        0.14       0.14       0.03       0.00        0.02       -0.01
    
    Solar irradiance                      0.23       0.24        0.23       0.22       0.07       0.07        0.01       0.02
    
    Stratospheric aerosols                  0.00       0.00        0.00       0.00       -0.08      -0.03       -0.06       0.04
    
    Trop. aerosol direct forcing              -0.41       -0.38       -0.52       -0.60       -0.28      -0.23       -0.18       -0.10
    
    Trop. aerosol indirect forcing                                  -0.87       -0.77       -0.27      -0.29       -0.14       -0.05
    
    Sum of above                                             1.86       1.90       0.49       0.44        0.40       0.30
    
    All forcings at once                                         1.77       1.75       0.53       0.61        0.44       0.29
    
                                                           Source: Reprinted with Permission of Springer Publishing from Hansen et al. (2007,1905971.
                                          Instantaneous (Fi), adjusted (Fa), fixed SST (Fs) and effective (Fe) forcings are defined in Hansen et al. (2005, 0590871
    
    
                      The time dependence of the total aerosol forcing used as well as the individual species
                 components is shown in Figure 9-81. The resultant warming,  0.53 (± 0.04) °C including these
                 and other forcings (Table 9-17), is less than the observed value of 0.6-0.7°C from 1880-2003.
                 Hansen et al. (2007, 190597) further show that a reduction in sulfate optical thickness and the
                 direct aerosol effect by 50%, which also reduced the aerosol indirect effect by 18%, produces a
                 negative aerosol forcing from  1880-2003 of-0.91 W/m2 (down from-1.37 W/m2 with this
                 revised forcing). The model now warms 0.75°C over that time. Hansen et al. (2007, 190597)
                 defend this change by noting that sulfate aerosol removal over North America and western
                 Europe during the 1990s led to a cleaner atmosphere. Note that the comparisons shown in the
                 previous section suggest that the GISS model already underestimates aerosol optical depths; it
                 is thus trends that are the issue here.
                      The magnitude of the indirect effect used by Hansen et al. (2005, 190596) is roughly
                 calibrated to reproduce the observed change in diurnal temperature cycle and is consistent with
                 some satellite observations. However, as Anderson et al. (2003, 054820) note, the forward
                 calculation of aerosol negative forcing covers a much larger range than is normally used in
                 GCMs; the values chosen, as in this case, are consistent with the inverse reasoning estimates of
                 what is needed to produce the  observed warming, and hence generally consistent with current
                 model climate sensitivities. The authors justify this approach by claiming that paleoclimate
                 data indicate a climate sensitivity of close to 0.75 (± 0.25)°C/(W/m2), and therefore something
                 close to this magnitude of negative forcing is reasonable. Even this stated range leaves
                 significant uncertainty in climate  sensitivity and the magnitude of the aerosol negative forcing.
                 Furthermore, IPCC (2007, 092765) concluded that paleoclimate data are not capable of
                 narrowing the range of climate sensitivity, nominally 0.375-1.13 °C/(W/m2), because of
                 uncertainties in paleoclimate forcing and response; so from this perspective the total aerosol
                 forcing is even less constrained than the GISS estimate. Hansen et al. (2007, 190597)
                 acknowledge that "an equally  good match to observations  probably could be obtained from a
                 model with larger  sensitivity and  smaller net forcing, or a model with smaller sensitivity and
                 larger forcing".
    December 2009                                          9-148
    

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                  BC Industrial
                  BC Biomass
                  OC Industrial
                  OC Biomass
                  Nitrates
                  Sulfates
                                                                   — BC Industrial
                                                                   	BC Biomass
                                                                   —•— OC Industrial
                                                                   	OC Biomass
                                      Nitrates
                                      Sulfates
                                                                       1875
                                                                               1900
                                                                                       1925
                                                                                              1950
                                                                                                      1975
                                                                                                              2000
                                                                       - Black Carbon Forcings
                                                                       - Reflective Aerosol Forcings
                                                                       - All Aerosols
                                                                       1875
                                                                               1900
                                                                                       1925
                                                                                              1950
                                                                                                      1975
                                                                                                              2000
                                                                Source: Reprinted with Permission of Springer from Hansen et al. (2007,1905971.
    
    
    Figure 9-81.    Time dependence of aerosol optical thickness (left) and climate forcing (right).
                     Note that as specified, the aerosol trends are all "flat" from 1990-2000.
    
                     The GFDL model results for global mean ocean temperature change (down to 3 km depth)
                 for the time period 1860-2000 is shown in Figure 9-82, along with the different contributing
                 factors (Delworth et al., 2005, 190055). This is the same GFDL model whose aerosol
                 distribution was discussed previously. The aerosol forcing produces a cooling on the order of
                 50% that of greenhouse warming (generally similar to that calculated by the GISS model,
                 Table 9-17). Note that this was achieved without any aerosol indirect effect.
                     The general model response noted by IPCC, as discussed in the introduction was that the
                 total aerosol forcing of -1.3 W/m2 reduced the greenhouse forcing of near 3 W/m by about
                 45%, in the neighborhood of the GFDL and GISS forcings. Since the average model sensitivity
                 was close to 0.75 °C/(W/m ), similar to the sensitivities of these models, the necessary
                 negative forcing is therefore similar. The agreement cannot therefore be used to validate the
                 actual aerosol effect until climate sensitivity itself is better known.
                     Is there some way to distinguish between greenhouse gas and aerosol forcing that would
                 allow the observational record to indicate how much of each was really occurring? This
                 question of attribution has been the subject of numerous papers, and the full scope of the
                 discussion is beyond the range of this (CCSP SAP2.3) report. It might be briefly noted that
                 Zhang et al. (2006,  157722) using results from several climate models and including both
                 spatial and temporal patterns, found that the climate responses to greenhouse gases and  sulfate
                 aerosols are correlated, and separation is possible only occasionally, especially at global scales.
                 This conclusion appears to be both model and method-dependent: using time-space
                 distinctions as opposed to trend detection may work differently in different models (Gillett et
                 al., 2002, 190576). Using multiple models helps primarily by providing larger-ensemble sizes
                 for statistics (Gillett et al., 2002, 190578). However, even separating between the effects of
                 different aerosol types  is difficult. Jones et al. (2005, 155885) concluded that currently the
                 pattern of temperature change due to black carbon is indistinguishable from the sulfate aerosol
                 pattern. In contrast, Hansen et al. (2005, 059087) found that absorbing aerosols produce a
                 different global response than other forcings, and  so may be distinguishable. Overall, the
                 similarity in response to all these very different forcings is undoubtedly due to the importance
                 of climate feedbacks in amplifying the forcing, whatever its nature.
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                                 -0.06 -
                                   1860   1880   1900   1920   1940   1960   1980   2000
    
                                                        Source: Courtesy of the American Geogphysical Union from Delworth et al. (2005,1900551.
    
    
    Figure 9-82.    Change in global mean ocean temperature (left axis) and ocean heat content
                     (right axis) for the top 3000 m due to different forcings in the GFDL model.
                     WMGG includes all greenhouse gases and ozone; NATURAL includes solar and
                     volcanic aerosols (events shown as green triangles on the bottom axis).
                     Observed ocean heat content changes are shown as well.
    
                     Distinctions in the climate response do appear to arise in the vertical, where absorbing
                aerosols produce warming that is exhibited throughout the troposphere and into the
                stratosphere, whereas reflective aerosols cool the troposphere but warm the stratosphere
                (Hansen et al., 2005, 059087; IPCC, 2007, 092765). Delworth et al. (2005, 190055) noted that
                in the ocean, the cooling effect of aerosols extended to greater depths, due to the thermal
                instability associated with cooling the ocean surface. Hence the temperature response at levels
                both above and below the surface may provide an additional  constraint on the magnitudes of
                each of these forcings, as may the difference between Northern and Southern Hemisphere
                changes (IPCC, 2007, 092765, Chapter 9). The profile of atmospheric temperature response
                will be useful to the extent that the vertical profile  of aerosol absorption, an important
                parameter to measure, is known.
    
    
           Implications for Climate Model Simulations
    
                     The comparisons in Sections 9.3.6.2 and 9.3.6.3 suggest that there are large differences in
                model calculated aerosol distributions, mainly because of the large uncertainties in modeling
                the aerosol atmospheric processes in addition to the uncertainties in emissions. The fact that
                the total optical depth is in better agreement between models than the individual components
                means that even with similar optical depths, the aerosol direct forcing effect can be quite
                different, as shown in the AeroCom studies. Because the diversity among models and
                discrepancy between models and observations are much larger at the regional level than in
                global average, the assessment of climate response (e.g., surface temperature change) to
                aerosol forcing would be more accurate for global  average than for regional or hemispheric
                differentiation. However, since aerosol forcing is much more pronounced on regional than on
                global scales because of the highly variable aerosol distributions, it is insufficient or even
                misleading to just get the global average right.
                     The indirect effect is strongly influenced by the aerosol concentrations, size, type, mixing
                state, microphysical processes, and vertical profile. As shown in previous sections, very large
                differences exist in those quantities even among the models having similar AOD. Moreover,
                modeling aerosol indirect forcing presents more challenges than direct forcing because there is
                so far no rigorous observational data, especially on a global scale, that one can use to test the
                model simulations. As seen in the comparisons of the GISS and GFDL model climate
                simulations for IPCC AR4, aerosol indirect forcing was so poorly constrained that it was
                completely ignored by one model (GFDL) but used by another (GISS) at a magnitude that is
                more than half of the direct forcing, in order to reproduce the observed surface temperature
                trends. A majority of the climate models used in IPCC AR4 do not consider indirect effects;
                the ones that did were mostly limited to highly simplified sulfate indirect effects (Table 9-16).
                Improvements must be made to at least the degree  that the aerosol indirect forcing can no
                longer be used to mask the deficiencies in estimating the climate response to greenhouse gas
                and aerosol direct RF.
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    9.3.6.7.    Outstanding Issues
                     Clearly there are still large gaps in assessing the aerosol impacts on climate through
                 modeling. Major outstanding issues and prospects of improving model simulations are
                 discussed below.
    
    
           Aerosol composition
    
                     Many global models are now able to simulate major aerosol types such as sulfate, black
                 carbon, and POM, dust, and sea salt, but only a small fraction of these models simulate nitrate
                 aerosols or consider anthropogenic secondary organic aerosols. And it is difficult to quantify
                 the dust emission from human activities. As a result, the IPCC AR4 estimation of the nitrate
                 and anthropogenic dust TOA forcing was left with very large uncertainty. The next generation
                 of global models should therefore have a more comprehensive suite of aerosol compositions
                 with better-constrained anthropogenic sources.
    
    
           Aerosol absorption
    
                     One of the most critical parameters in aerosol direct RF and aerosol impact on
                 hydrological cycles is the aerosol absorption. Most of the absorption is from BC despite its
                 small contribution to total aerosol short and long-wave spectral ranges, whereas POM absorbs
                 in the near UV. The aerosol absorption or SSA, will have to be much better represented in the
                 models through improving the estimates of carbonaceous and dust aerosol sources, their
                 atmospheric distributions, and optical properties.
    
    
           Aerosol indirect effects
    
                     The activation of aerosol particles into CCN depends not only on particle size but
                 chemical composition, with the relative importance of size and composition unclear. In current
                 aerosol-climate modeling, aerosol size distribution is generally prescribed and  simulations of
                 aerosol composition have large uncertainties. Therefore the model estimated "albedo effect"
                 has large uncertainties. How aerosol would influence cloud lifetime/ cover is still in debate.
                 The influence of aerosols on other aspects of the climate system, such as precipitation, is even
                 more uncertain, as are the physical processes involved. Processes that determine aerosol size
                 distributions, hygroscopic growth, mixing state, as well as CCN concentrations, however, are
                 inadequately represented in most of the global models. It will also be difficult to improve the
                 estimate of indirect effects until the models can produce more realistic cloud characteristics.
    
    
           Aerosol impacts on surface  radiation and atmospheric heating
    
                     Although these effects are well acknowledged to play roles in modulating atmospheric
                 circulation and water cycle, few coherent or comprehensive modeling studies have focused on
                 them, as compared to the efforts that have gone to assessing aerosol RF at TOA. They have not
                 yet been addressed in the previous IPCC reports. Here, of particular importance is to improve
                 the accuracy of aerosol absorption.
    
    
           Long-term trends of aerosol
    
                     To assess the aerosol effects  on climate change the long-term variations of aerosol amount
                 and composition and how they are related to the emission trends in different regions have to be
                 specified. Simulations of historical aerosol trends can be problematic since historical emissions
                 of aerosols have shown large uncertainties - as information is difficult to obtain on past source
                 types, strengths, and even locations. The IPCC AR4 simulations used several alternative
                 aerosol emission histories,  especially for BC and POM aerosols.
    
    
           Climate modeling
    
                     Current aerosol simulation capabilities from CTMs have  not been fully implemented in
                 most models used in IPCC AR4 climate simulations. Instead, a majority employed simplified
                 approaches to account for aerosol effects, to the extent that aerosol representations in the
                 GCMs, and the resulting forcing estimates, are inadequate. The oversimplification occurs in
                 part because the modeling complexity and computing resource would be significantly
                 increased if the full suite of aerosols were fully coupled in the climate models.
    
    
           Observational constraints
    
                     Model improvement has been hindered by a lack of comprehensive datasets that could
                 provide multiple constraints for the key parameters simulated in the model. The extensive
                 AOD coverage from satellite observations and AERONET measurements has helped a great
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                 deal in validating model-simulated AOD over the past decade, but further progress has been
                 slow. Large model diversities in aerosol composition, size, vertical distribution, and mixing
                 state are difficult to constrain, because of lack of reliable measurements with adequate spatial
                 and temporal coverage (see Chapter 2 of the CCSP SAP2.3).
    
    
           Aerosol radiative forcing
    
                     Because of the large spatial and temporal differences in aerosol sources, types, emission
                 trends, compositions, and atmospheric concentrations, anthropogenic aerosol RF has profound
                 regional and seasonal variations. So it is an insufficient measure of aerosol RF scientific
                 understanding, however useful, for models (or observation-derived products) to converge only
                 on globally and annually averaged TOA RF values and accuracy. More emphasis should be
                 placed on regional and seasonal comparisons, and on climate effects in addition to direct RF at
                 TOA.
    
    
    
    9.3.6.8.   Conclusions
    
                     From forward modeling studies, as discussed in the IPCC (2007, 092765) , the direct
                 effect of aerosols since pre-industrial times has resulted in a negative RF of about -0.5 ± 0.4
                 W/m2. The RF due to cloud albedo or brightness effect is estimated to be -0.7 (-1.8 to -0.3)
                 W/m2. Forcing of similar magnitude has been used in some modeling studies for the effect
                 associated with cloud lifetime, in lieu of the cloud brightness influence. The total negative RF
                 due to aerosols according to IPCC (2007, 092765) estimates is therefore -1.3 (-2.2 to -0.5)
                 W/m2. With the inverse approach, in which aerosols provide forcing necessary to produce the
                 observed temperature change, values range from -1.7 to -0.4 W/m2 (IPCC, 2007, 092765) .
                 These results represent a substantial advance over previous assessments (e.g., IPCC TAR), as
                 the forward model estimated and inverse approach required aerosol TOA forcing values are
                 converging. However, large uncertainty ranges preclude using the forcing and temperature
                 records to more accurately determine climate sensitivity.
                     There are now a few dozen models that simulate a comprehensive  suite of aerosols. This
                 is done primarily in the CTMs.  Model inter-comparison studies have shown that models have
                 merged at matching the global annual averaged AOD observed by satellite instruments, but
                 they differ greatly in the relative amount of individual components, in vertical distributions,
                 and in optical properties. Because of the great spatial and temporal variations  of aerosol
                 distributions, regional and seasonal diversities are much larger than that of the global  annual
                 mean. Different emissions and differences  in atmospheric processes, such as transport,
                 removal,  chemistry, and aerosol microphysics, are chiefly responsible for the spread among the
                 models. The varying component contributions then lead to differences in aerosol direct RF, as
                 aerosol scattering and absorption properties depend on aerosol size and type. They also impact
                 the calculated indirect RF, whose variations are further amplified by the wide range of cloud
                 and convective parameterizations in models. Currently, the largest aerosol RF uncertainties are
                 associated with the aerosol indirect effect. Most climate models used for the IPCC AR4
                 simulations employed simplified approaches, with aerosols specified from stand-alone CTM
                 simulations. Despite the uncertainties in aerosol RF and widely varying model climate
                 sensitivity, the IPCC AR4 models were generally able to reproduce the  observed temperature
                 record for the past century. This is because models with lower/higher climate sensitivity
                 generally used less/more negative aerosol forcing to offset the greenhouse gas warming. An
                 equally good match to observed surface temperature change in the past could be obtained from
                 a model with larger climate sensitivity and smaller net forcing, or a model with smaller
                 sensitivity and larger forcing (Hansen et al., 2007, 190597). Obviously, both greenhouse gases
                 and aerosol effects have to be much better  quantified in future assessments.
                     Progress in better quantifying aerosol impacts on climate will only be made when the
                 capabilities of both aerosol observations and representation of aerosol processes in models are
                 improved. The primary  concerns and issues discussed in this chapter of the CCSP SAP2.3
                 include:
                          Better representation of aerosol composition and absorption in the global models
                          Improved theoretical understanding of subgrid-scale processes crucial to aerosol-
                          cloud interactions and lifetime
                          Improved aerosol microphysics and cloud parameterizations
                          Better understanding of aerosol effects on surface radiation and hydrological cycles
                          More focused analysis on regional and seasonal variations of  aerosols
                          More reliable  simulations of aerosol historic long-term trends
                          More sophisticated climate model simulations with coupled aerosol and cloud
                          processes
                          Enhanced satellite observations of aerosol type,  SSA, vertical distributions, and
                          aerosol radiative effect at TOA; more coordinated field experiments to provide
                          constraints on aerosol chemical, physical, and optical properties.
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    9.3.7.  Fire as a Special Source of PM Welfare Effects
    
          Much interest has developed in defining more precisely the role of pyrogenic C in the boreal
    C cycle. This is due to: (1) the resistance of pyrogenic C to decomposition; (2) its influence on soil
    processes; and (3) the absorption of solar radiation by soot aerosols (Preston  and Schmidt, 2006,
    156030).
          Preston and Schmidt (2006, 156030) reviewed the current state of knowledge regarding
    atmospheric emissions of pyrogenic C in the boreal zone. They considered chemical structures,
    analytical methods, formation,  characteristics in soil, loss mechanisms, and longevity. Biomass is
    largely converted to gaseous forms during burning, but up to several percent is converted to
    pyrogenic C, and this includes charcoal and BC. Charcoal is defined visually; BC is defined
    chemically by its resistance to oxidation in the laboratory. Andreae and Gelencser (2006, 156215)
    reviewed a different category of light-absorbing carbon, referred to as brown carbon.
          Within the boreal zone, fire is a critical driver of ecosystem process and nutrient cycling
    (Hicke et al, 2003, 156545). For example, Bachelet et al. (2005,  156241) estimated that 61% of the
    C gained in Alaska by primary  production of boreal forests between  1922 and 1996 was lost to fire.
          An updated modeling effort to evaluate the radiative effects of aerosols was presented by Stier
    et al. (2007, 157012). Inclusion of refractive indices recommended byBond and Bergstrom (2005,
    155696) significantly increased aerosol RF and resulted in better agreement with sun-photometer
    estimates. Although this stage of climate modeling improved the representation of aerosols, large
    uncertainties remain regarding the effects of aerosol mixing and aerosol-cloud interactions.
    Furthermore, Stier et al. (2007, 157012) emphasized that these types of modeling efforts are
    dependent upon emission estimates that are likely to vary by a factor of 2  or more.
          One important reason for the acknowledged uncertainty in estimating global emissions of
    carbonaceous aerosols is the influence of intermittent fires that can occur at scales large enough to
    affect hemispheric aerosol concentrations. To better quantify the effects of large-scale fire, Generoso
    et al. (2007, 155786) used satellite observations of boreal fires in Russia in 2003 to evaluate the
    performance of a global chemistry and transport model in simulating aerosol  optical thickness,
    transport, and deposition. Emissions estimates of BC and OC were adjusted in the model to better
    match satellite observations of pollutant transport over the North Pacific. This resulted in an increase
    in optical thickness and BC deposition by a factor of 2. The adjusted model estimated that the fires
    contributed 16-33% of the optical thickness and 40-56% of BC deposition north of 75° N in the
    spring and summer of 2003.
          Large fires also occurred over the Iberian Peninsula and Mediterranean coast during 2003. A
    meso-scale atmospheric transport model was used with ground-based measurements and satellite
    optical measurements to characterize the dispersion of emitted smoke particles and quantify radiative
    effects across Europe (Hodzic et al., 2007, 156553). The modeled wildfire emissions resulted in
    increases in PM2.5 concentrations from 20 to 200%. The increased aerosol concentration was
    estimated to increase radiative forcing by 10-35 W/m2 during the period of strong fire influence.
    Absorption of radiation by BC was also estimated to  decrease rates of photolysis by 30%. In this
    simulation, all particles were assumed to be internally mixed,  and secondary  aerosol formation was
    not considered. Meteorological conditions in Europe during the exceptionally hot summer of 2003
    were linked to enhanced photochemically derived pollutants, increased wild fires, and elevated
    aerosol concentrations in an analysis by Vautard et al. (2007, 106012).
          In addition to incidental fires, routine biomass burning,  usually associated with agriculture in
    eastern Europe, also has been shown to contribute to hemispheric concentrations of carbonaceous
    aerosols. In the spring of 2006, the most severe air pollution levels in the Arctic to date were
    recorded (Stohl et al., 2006, 156100).  Atmospheric transport modeling coupled with satellite fire
    detection data identified biomass burning for agriculture as the primary  cause of the high pollution
    levels. Concentrations of PM2.5 peaked during the pollution episode at values of an order of
    magnitude greater than those recorded prior to the episode. The increased transport of pollution into
    the Arctic during 2006 was attributed to weather conditions that delayed preparations for crop
    planting into May. Weather patterns favorable for pollutant transport into the  Arctic were related to
    unusually warm weather in late April  and May, when the majority of agricultural biomass burning
    took place that year.
          In the summer of 2004, 2.7 million ha were burned by wildfire in Alaska and  3.1 million ha
    were burned in Canada. Effects on atmospheric air quality were measured throughout the Arctic,
    although the concentrations of particulates varied considerably. Aerosol optical depths were also
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    increased at all measurement stations, which indicated that the fires were likely to have had a
    significant effect on the atmospheric radiation budget for the Arctic (Stohl et al., 2006, 156100). At
    one site, a pronounced drop in albedo was observed due presumably to high deposition of light
    absorbing particulates on the snow surface by the North American fires in 2004.
          Investigations of the effects of large fires on climate forcing have typically focused on the
    absorptive  effects of BC. However, these fires also release large amounts of CO2 and CH4, as well as
    light scattering compounds such as OC, and can enhance cloud formation. These fires also increase
    radiative surface absorption through BC deposition on snow and ice, and alter surface albedo and
    ecosystem  energy budgets within the burn perimeter. Randerson et al. (2006, 156038) estimated the
    net climate forcing of greenhouse gases, aerosols, BC deposition on snow and ice and changes in
    albedo  for the year subsequent to a fire and for 80 years in the future in interior Alaska. The net
    effect of the fire in the first year was an increase in radiative forcing, but over the 80-year recovery
    period, average net annual radiative forcing was decreased by the fire.
    
    
    
    9.3.8.  Radiative Effects of Volcanic  Aerosols
    
          Section 9.3.8.1. comes directly from IPCC AR4 Chapter 2,  Section 2.7.2, with section, table,
    and figure numbers changed to be internally consistent with this ISA.
    
    
    
    9.3.8.1.   Explosive Volcanic Activity
    
    
          Radiative Effects of Volcanic Aerosols
    
                    Volcanic sulfate aerosols are formed as a result of oxidation of the sulfur gases emitted by
                explosive volcanic eruptions into the stratosphere. The process of gas-to-particle conversion
                has an e-folding time of roughly 35 days (Bluth et al., 1992, 192029: Read et al., 1993,
                192031). The e-folding time (by mass) for sedimentation of sulfate aerosols is typically about
                12 to 14 months (Baran and Foot, 1994, 192032: Barnes and Hofmann, 1997, 192044: Bluth
                et al., 1997, 192045: Lambert et al., 1993, 192231). Also emitted directly during an eruption
                are volcanic ash particulates (siliceous material). These are particles usually larger than 2 um
                that sediment out of the stratosphere fairly rapidly due to gravity (within three months or so),
                but could also play a role in the radiative perturbations in the immediate aftermath of an
                eruption. Stratospheric aerosol data incorporated for climate change simulations tends to be
                mostly that of the sulfates (Ammann et al., 2003, 192057: Hansen et al., 2002, 049177:
                Ramachandran et al., 2000, 192050: Sato et al., 1993, 192046:  Stenchikov et al., 1998,
                192049: Tett et al., 2002, 192053). As noted in the Second Assessment Report (SAR) and the
                TAR, explosive volcanic events are episodic, but the stratospheric aerosols resulting from them
                yield substantial transitory perturbations to the radiative energy balance of the planet, with
                both shortwave and longwave effects sensitive to the microphysical characteristics of the
                aerosols (e.g., size distribution).
                    Long-term ground-based and balloon-borne instrumental observations have resulted in an
                understanding of the optical effects and microphysical evolution of volcanic aerosols (Deshler
                et al., 2003, 192058: Hofmann et al., 2003, 192062). Important ground-based observations of
                aerosol characteristics from pre-satellite era spectral extinction measurements have been
                analysed by Stothers (2001, 192233: 2001, 192232), but they do not provide global coverage.
                Global observations of stratospheric aerosol over the last 25 years have been possible owing to
                a number of satellite platforms, for example, TOMS and TOYS have been used to estimate
                SO2 loadings from volcanic eruptions (Krueger et al., 2000, 192234: Prata et al., 2003,
                192235). The Stratospheric Aerosol and Gas Experiment (SAGE) and Stratospheric Aerosol
                Measurement (SAM) projects (e.g., McCormick and Trepte, 1987, 192328) have provided
                vertically resolved stratospheric aerosol spectral extinction data for over 20 years, the longest
                such record. This data set has significant gaps in coverage  at the time of the El Chichon
                eruption in 1982 (the second most important in the  20th century after Mt. Pinatubo in 1991)
                and when the aerosol cloud is dense; these gaps have been partially filled by lidar
                measurements and field campaigns (e.g., Antuna et al., 2003, 192251: Thomason and Peter,
                2006, 192248).
                    Volcanic aerosols transported in the atmosphere to polar regions are preserved in the ice
                sheets, thus recording the history of the Earth's volcanism  for thousands of years (Kruysse,
                1971,192236: Mosley-Thompson et al., 2003, 192255: Palmer et al., 2002, 192319). However,
                the atmospheric loadings obtained from ice records suffer from uncertainties due to imprecise
                knowledge of the latitudinal distribution of the aerosols, depositional noise that can affect the
                signal for an individual eruption in a single ice core, and poor constraints on aerosol
                microphysical properties. The best-documented explosive volcanic event to date, by way of
                reliable and accurate observations, is the 1991 eruption of Mt. Pinatubo. The growth and decay
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                 of aerosols resulting from this eruption have provided a basis for modeling the RF due to
                 explosive volcanoes. There have been no explosive and climatically significant volcanic events
                 since Mt. Pinatubo. As pointed out in Ramaswamy et al. (2001, 156899), stratospheric aerosol
                 concentrations are now at the lowest concentrations since the satellite era and global coverage
                 began in about 1980. Altitude dependent stratospheric optical observations at a few
                 wavelengths, together with columnar optical and physical measurements, have been used to
                 construct the time-dependent global field of stratospheric aerosol size distribution formed in
                 the aftermath of volcanic events. The wavelength-dependent stratospheric aerosol single-
                 scattering characteristics calculated for the solar and longwave spectrum are deployed in
                 climate models to account for the resulting radiative (shortwave plus longwave) perturbations.
                     Using available satellite- and ground-based observations, Hansen et al. (2002, 049177)
                 constructed a volcanic aerosols data set for the 1850-1999 period (Sato et al., 1993, 192046).
                 This has yielded zonal mean vertically resolved aerosol optical depths for visible wavelengths
                 and column average effective radii. Stenchikov et al. (2006, 192260) introduced a slight
                 variation to this data set, employing UARS observations to modify the effective radii relative
                 to Hansen et al. (2002, 049177), thus accounting for variations with altitude. Ammann et al.
                 (2003, 192057) developed a data  set  of total aerosol optical depth for the period since 1890
                 that does not include the Krakatau eruption. The data set is based on empirical estimates of
                 atmospheric loadings, which are then globally distributed using a simplified parameterization
                 of atmospheric transport, and employs a fixed aerosol effective radius (0.42 um) for
                 calculating optical properties. The above data sets have essentially provided the bases for the
                 volcanic aerosols implemented in virtually all of the models that have performed the 20th-
                 century  climate integrations (Stenchikov et al., 2006, 192260). Relative to Sato et al. (1993,
                 192046), the Ammann et al. (2003, 192057) estimate yields  a larger value of the optical depth,
                 by 20 to 30% in the second part of the 20th century, and by 50% for eruptions at the end of
                 19th and beginning of 20th century, for example, the 1902 Santa Maria eruption (Figure 9-83).
                     The global mean RF calculated using the Sato et al. (1993, 192046) data yields a peak in
                 radiative perturbation of about -3  W/m2 for the strong (rated in terms of emitted SO2) 1860 and
                 1991 eruptions of Krakatau and Mt. Pinatubo, respectively. The value is reduced to about -2
                 W/m2 for the relatively less intense El Chichon and Agung eruptions (Hansen et al., 2002,
                 049177). As expected from the arguments above, Ammann's RF is roughly 20  to 30% larger
                 than Sato's RF.
                     Not all features of the aerosols are well quantified, and extending and improving the data
                 sets remains an important area of research. This includes improved  estimates of the aerosol
                 size parameters (Bingen et al., 2004,  192262), a new approach for calculating aerosol optical
                 characteristics using SAGE and UARS data (Bauman et al., 2003, 192265). and
                 intercomparison of data from different satellites and combining them to fill gaps (Randall et
                 al., 2001, 192268). While the aerosol characteristics are better constrained for the Mt. Pinatubo
                 eruption, and to some extent for the El Chichon and Agung eruptions, the reliability degrades
                 for aerosols from explosive volcanic events further back in time as there are few, if any,
                 observational constraints on their optical depth and size evolution.
                     The radiative effects due to volcanic aerosols from major eruptions are manifest  in the
                 global mean anomaly of reflected solar radiation; this variable affords a good estimate of
                 radiative effects that can actually  be tested against observations. However, unlike RF, this
                 variable contains effects due to feedbacks  (e.g., changes in cloud distributions) so that it is
                 actually more a signature of the climate response. In the case of the Mt.  Pinatubo eruption,
                 with a peak global visible optical  depth of about 0.15, simulations yield a large negative
                 perturbation as noted above of about -3 W/m2 (Hansen et al., 2002,  049177: Ramachandran et
                 al., 2000, 192050) (see also Section 9.2 of the IPCC AR4). This modeled estimate of reflected
                 solar radiation  compares reasonably with ERBS observations (Minnis et al., 1993, 190539).
                 However, the ERBS observations were for a relatively short duration, and the model-
                 observation comparisons are likely affected by differing cloud effects in simulations and
                 measurements. It is interesting to  note (Stenchikov et al., 2006, 192260) that, in the Mt.
                 Pinatubo case,  the Goddard Institute  for Space Studies (GISS) models that use the Sato et al.
                 (1993, 192046) data yield an even greater solar reflection than the National Center for
                 Atmospheric Research (NCAR) model that uses the larger (Ammann et al., 2003, 192057)
                 optical depth estimate.
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                     0.2
    
    
                    0.18
    
    
                    0.16
    
    
                    0.14
                               Volcanic  Aerosol  Total  Visible Optical  Depth
    Sato  et -g|. (1993)
                           1870 1880 1800 1900  1810  1920 1830 1040 1950 1960 1970  1960  1990
                                                     lima (years)
    Figure 9-83.    Visible (wavelength 0.55 urn) optical depth estimates of stratospheric SC>42~
                    aerosols formed in the aftermath of explosive volcanic eruptions that occurred
                    between 1860 and 2000. Results are shown from two different data sets that have
                    been used in recent climate model integrations. Note that the Ammann et al.
                    (2003,192057) data begins in 1890.
    
    
    
           Thermal, Dynamical and Chemistry Perturbations Forced by Volcanic Aerosols
    
                     Four distinct mechanisms have been invoked with regards to the climate response to
                volcanic aerosol RF. First, these forcings can directly affect the Earth's radiative balance and
                thus alter surface temperature. Second, they introduce horizontal and vertical heating
                gradients; these can alter the stratospheric circulation, in turn affecting the troposphere. Third,
                the forcings can interact with internal climate system variability (e.g., El Nino-Southern
                Oscillation, North Atlantic Oscillation, Quasi- Biennial Oscillation) and dynamical noise,
                thereby triggering, amplifying or shifting these modes (see Section 9.2 of the IPCC AR4)
                (Stenchikov et al., 2004, 192274: Yang  and Schlesinger, 2001,192270). Fourth, volcanic
                aerosols provide surfaces for heterogeneous chemistry affecting global stratospheric ozone
                distributions (Chipperfield et al., 2003,  192275) and perturbing other trace gases for a
                considerable period following an eruption. Each of the above mechanisms has its own spatial
                and temporal response pattern. In addition, the mechanisms could depend on the background
                state of the climate system, and thus on other forcings (e.g., due to well-mixed gases) (Meehl
                et al., 2004, 192279X or interact with each other.
                    The complexity of radiative-dynamical response forced by volcanic impacts suggests that
                it is important to calculate aerosol radiative effects interactively within the model rather than
                prescribe them (Andronova et al., 1999, 192286; Broccoli et al., 2003, 192283). Despite
                differences in volcanic aerosol parameters employed, models computing the aerosol radiative
                effects interactively yield tropical and global mean lower-strata spheric warmings that are fairly
                consistent with each other and with observations (Hansen et al., 2002, 049177: Ramachandran
                et al., 2000, 192050: Ramaswamy et al., 2006, 192284: Stenchikov et al., 2004, 192274: Yang
                and Schlesinger, 2001, 192270): however, there is a considerable range in the responses in the
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                polar stratosphere and troposphere. The global mean warming of the lower stratosphere is due
                mainly to aerosol effects in the longwave spectrum, in contrast to the flux changes at the TOA
                that are essentially due to aerosol effects in the solar spectrum. The net radiative effects of
                volcanic aerosols on the thermal and hydrologic balance (e.g., surface temperature and
                moisture) have been highlighted by recent studies (Free  and Angell, 2002, 192281; Jones et
                al, 2003, 192278) (see Chapter 6 of the IPCC AR4). See Chapter 9 (of the IPCC AR4) for
                significance of the simulated responses and model-observation comparisons for 20th-century
                eruptions. A mechanism closely linked to the optical depth perturbation and ensuing warming
                of the tropical lower stratosphere is the potential change in the cross-tropopause water vapour
                flux (Joshi and Shine, 2003, 192327) (see Section 2.3.7 of the IPCC AR4).
                    Anomalies in the volcanic-aerosol induced global radiative heating distribution can force
                significant changes in atmospheric circulation, for example, perturbing the equator-to-pole
                heating gradient (Ramaswamy et al., 2006, 192273; Stenchikov et al., 2002, 192277) (see
                Section 9.2 of the IPCC AR4) and forcing a positive phase of the Arctic Oscillation that in turn
                causes a counterintuitive boreal winter warming at middle and high latitudes over Eurasia and
                North America (Miller et al., 2005, 192258: Perlwitz and Graf, 2001, 192271: Perlwitz and
                Harnik, 2003, 192264:  Rind et al., 2005, 192261: Shindell et al., 2003, 192069: Shindell et al.,
                2004, 192267: Stenchikov et al., 2002, 192277: Stenchikov et al., 2004, 192274: Stenchikov et
                al., 2006, 192260).
                    Stratospheric aerosols affect the chemistry and transport processes in the stratosphere,
                resulting in the depletion of ozone (Brasseur and Granier, 1992, 192256: Chipperfield et al.,
                2003, 192275: Solomon et al., 1996, 192252: Tie et al., 1994, 192253). Stenchikov et al.
                (2002, 192277) demonstrated a link between ozone depletion and Arctic Oscillation response;
                this is essentially a secondary radiative mechanism induced by volcanic aerosols through
                stratospheric chemistry. Stratospheric cooling in the polar region associated with a stronger
                polar vortex initiated by volcanic effects can increase the probability of formation of polar
                stratospheric clouds and therefore enhance the rate of heterogeneous chemical destruction of
                stratospheric ozone, especially in the NH (Tabazadeh et al., 2002, 192250). The above studies
                indicate effects on the stratospheric ozone layer in the wake of a volcanic eruption and under
                conditions of enhanced anthropogenic halogen loading. Interactive microphysics-chemistry-
                climate models (Dameris et al., 2005, 192055: Rozanov et al., 2002, 192247: Rozanov et al.,
                2004, 192245: Shindell et al., 2003, 192069: Timmreck et al., 2003, 192254)
                     indicate that aerosol-induced stratospheric heating affects the dispersion of the volcanic
                aerosol cloud, thus affecting the spatial RF. However the models' simplified treatment of
                aerosol microphysics introduces biases; further, they usually overestimate the mixing at the
                tropopause level and intensity of meridional transport in the stratosphere (Douglass et al.,
                2003, 057260; Schoeberl et al., 2003, 057262). For present climate studies, it is practical to
                utilize simpler approaches that are reliably constrained by aerosol observations.
                    Because of its episodic and transitory nature, it is difficult to give a best estimate for the
                volcanic RF, unlike the other agents. Neither a best estimate nor a level of scientific
                understanding was given in the TAR. For the well-documented case of the explosive 1991 Mt.
                Pinatubo eruption, there is a good scientific understanding. However, the limited knowledge of
                the RF associated with prior episodic, explosive events indicates a low level of scientific
                understanding.
    9.3.9.  Other Special Sources and Effects
          International shipping has been identified as an additional source of carbonaceous aerosols.
    Simulations with a climate model that included aerosol effects and 3 different emissions inventories
    showed that shipping contributed 2.3-3.6% of the total SO42~ atmospheric aerosol content and
    0.4-1.4% of the total BC atmospheric aerosol content, based on global means in 2000. This modeling
    also showed that aerosol optical thickness over the Indian Ocean, the Gulf of Mexico, and the
    northeastern Pacific Ocean varied by 8 to 10%. The corresponding all-sky (that includes both cloudy
    and clear skies) direct radiative forcings ranged from -0.011 to -0.013 W/m . The greatest effect of
    aerosols emitted from global shipping is likely to be an increase in cloud formation and the resulting
    change in reflectivity of shortwave radiation. Aerosols from shipping were estimated to contribute
    17-39% of the total anthropogenic aerosol radiation forcing effect.
          When BC is deposited to the surface of ice or snow, solar absorption and heating occur at the
    surface. This can melt additional snow or ice at the surface and the reflectivity of the surface can
    change. Both factors affect aspects of climate.  Jacobson (2003, 155866; 2004, 155870) and Jacobson
    et al. (2004, 180362) estimated the warming due to fossil fuel BC and organic matter using the Gas,
    Aerosol, Transport, Radiation, General Circulation, Mesoscale and Ocean Model
    (GATOR-GCMOM). The modeling effort included consideration of the BC cycle, accounting for
    emissions, transport, aerosol coagulation, aerosol growth, cloud activation, aerosol-cloud
    coagulation, cloud-cloud coagulation, rainout, washout,  dry deposition, and processes of precipitated
    and dry-deposited BC in snow and sea ice.  Results suggested that BC absorption in snow and sea ice
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    increased near-surface temperatures over a 10-year simulation by about 0.06°K (Jacobson, 2003,
    189421).
          BC soot is a potentially important agent of climate warming in the Arctic, and northern boreal
    wildfires may contribute substantially to this effect. Soot is approximately twice as effective as CO2
    in altering surface air temperature, and can reduce sea ice formation and snow albedo (Hansen and
    Nazarenko, 2004, 156521).
          Kim et al. (2005, 155900) investigated the relationships between northern boreal wildfires and
    reductions in Arctic sea ice and glacial coverage. They modeled the FROSTFIRE boreal forest
    control burn (Hinzman et al., 2003, 155845) with respect to BC aerosol transport, dispersion, and
    deposition. Model results suggested that boreal wildfires could be a major source of BC soot to sea
    ice and glaciers in Alaska. This may exacerbate summer melting of sea ice and reduce recruitment of
    first-year ice into multiyear ice, thereby leading to an overall reduction in sea ice. Similarly,
    increased BC soot on glaciers would be expected to increase  summer melting and lead to an overall
    reduction in glacial coverage (Kim et al., 2005,  155900).
          Jacobson (2002, 155865) proposed, based on model simulations with 12 identifiable effects of
    aerosol particles on climate, emission reductions of fossil fuel particulate BC and associated organic
    matter could potentially slow warming for a specific period more than reduction of CO2 or CH4 for a
    specific period. Jacobson's (2006, 156599) calculations suggested that fossil fuel BC plus organic
    matter emissions reductions could eliminate 8-18% of total anthropogenic warming, and 20-45% of
    net warming after accounting for aerosol cooling, within a period of 3-5 years (Chock et al., 2003,
    155727). See also conflicting discussions (Feichter et al., 2003, 155772; Penner, 2003, 156851); and
    further responses (Jacobson, 2003, 155867; Jacobson, 2003,  155868; Jacobson, 2003, 155869;
    Penner, 2003, 156851).
          Bond  and Sun (2005, 156282) reviewed published data regarding the warming potential of
    BC, compared with CO2 and other GHG.  Climatic effects of GHG are generally compared on the
    basis of top-of-the-atmosphere, globally averaged changes in radiative balance. On that basis, BC is
    one of the largest individual warming agents,  after CO2 and perhaps CH4 (Bond and Sun, 2005,
    156282; Jacobson, 2000, 056378; Sato et al., 2003, 156947).
          Reddy and Boucher (2007, 156042) conducted an analysis that provided regional estimates of
    BC emissions from fossil fuels and biofuels. These estimates indicated  that East and Southeast Asia
    contributed over 50% of the global BC burden and its associated direct radiative forcing. Europe was
    found to be the largest BC contributor in the northern latitudes. The indirect effect of BC deposition
    on snow was also estimated to be highest for Europe.
          To improve understanding of the role of aerosols in climate forcing, Chung and Seinfeld
    (2002, 155732) estimated the global distribution of BC, primary organic particles (those directly
    emitted from combustion), secondary organic particles (primary organic compounds partially
    oxidized in the atmosphere), and  SO42~ aerosols to model the overall radiative forcing of these
    groups of compounds. The model was run with the assumption that the BC particles do not combine
    with OC or SO42~ particles (termed an external mixture), and with the assumption that the particles
    are represented by a core of BC surrounded by a shell of light scattering aerosols. Modeling results
    suggested an overall radiative cooling effect from aerosols ranging from -0.39 to -0.78 W/m2.
          Roberts and Jones (2004, 156052) used a climate modeling approach to compare possible
    effects of BC on climate warming to those attributable to emissions from greenhouse gases.  Results
    suggested that the warming effect from atmospheric BC aerosols may not be large relative to that
    from greenhouse gases. A different modeling approach by Roeckner et  al. (2006, 156920) evaluated
    the effects of BC and primary OC on climate under two scenarios of carbonaceous aerosol
    emissions. In the first scenario, BC and primary OC emissions decreased over Europe and China, but
    increased at  lower latitudes. In the second scenario, emissions were frozen at 2000 levels. The effects
    of both scenarios on mean global temperature were found to be small, but higher aerosol emissions
    at low latitudes did result in atmospheric heating and corresponding land surface cooling that led to
    increased precipitation and runoff in this simulation.
          Study  of BC effects in tropical climates was undertaken by Wang (2007, 156147). Substantial
    effects of direct radiative forcing by BC on the tropical Pacific were shown in model results that
    were similar to the El Nino Southern Oscillation activities both in the nature and scale of effects  with
    enhancement of the Indian monsoon circulation. The model suggested that atmospheric heating by
    radiation absorption by BC can form temperature and pressure anomalies that favor propagation of
    convection from western to central and eastern Pacific. More work will be needed to distinguish
    between the  aerosol signal and natural factors in controlling tropical precipitation in this region.
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    Table 9-18.   Overview of the different aerosol indirect effects and their sign of the net radiative flux
                 change at the top of the atmosphere (TOA).
    Effect
    Cloud albedo
    effect
    Cloud lifetime
    effect
    Semi-direct effect
    Glaciation indirect
    effect
    Thermodynamic
    effect
    Cloud Types
    Affected
    All clouds
    All clouds
    All clouds
    Mixed-phase
    clouds
    Mixed-phase
    clouds
    Process
    For the same cloud water or ice content more but smaller
    cloud particles reflect more solar radiation
    Smaller cloud particles decrease the precipitation efficiency
    thereby presumably prolonging cloud lifetime
    Absorption of solar radiation by absorbing aerosols affects
    static stability and the surface energy budget, and may lead to
    an evaporation of cloud particles
    An increase in IN increases the precipitation efficiency
    Smaller cloud droplets delay freezing causing super-cooled
    clouds to extend to colder temperatures
    Sign of Change
    in TOA Radiation
    Negative
    Negative
    Positive or Negative
    Positive
    Positive or Negative
    Potential
    Magnitude
    Medium
    Medium
    Small
    Medium
    Medium
    Scientific
    Understanding
    Low
    Very low
    Very low
    Very low
    Very low
                                                 Source: Reprinted with Permission of Cambridge University Press from Denman (2007,1563941
    Table 9-19.   Overview of the different aerosol indirect effects and their implications for the global
                 mean net shortwave radiation of the surface Fsfc (columns 2-4) and for precipitation
                 (columns 5-7).
    Effect
    Cloud albedo effect
    Cloud lifetime effect
    Semi-direct effect
    Glaciation indirect
    effect
    Sign of Change
    in Fsfc
    Negative
    Negative
    Negative
    Positive
    Potential
    Magnitude
    Medium
    Medium
    Large
    Medium
    Scientific
    Understanding
    Low
    Very low
    Very low
    Very low
    Sign of Change in
    Precipitation
    n.a.
    Negative
    Negative
    Positive
    Potential
    Magnitude
    n.a.
    Small
    Large
    Medium
    Scientific
    Understanding
    n.a.
    Very low
    Very low
    Very low
    Thermodynamic    Positive or
    effect          Negative
    Medium
                Very low
    Positive or Negative
                                                 Medium
    Very low
                                                 Source: Reprinted with Permission of Cambridge University Press from Denman (2007,156394)
    
    
          There are several other kinds of climate effects from aerosol PM. None is well understood or
    well quantified. The semi-direct effect, which involves absorption of solar radiation by soot particles
    followed by re-emission as thermal radiation, is expected to heat the air mass and increase its static
    stability relative to the surface. The semi-direct effect can also cause evaporation of cloud droplets,
    thereby partially offsetting the cloud albedo indirect effect. The glaciation effect involves an increase
    in IN, which is expected to cause rapid glaciation of a super-cooled liquid water cloud due to the
    differences in vapor pressure over ice and water. Unlike cloud droplets, these ice crystals can quickly
    reach precipitation size, with the potential to turn a non-precipitating cloud into a precipitating cloud.
    The thermodynamic effect involves a delay in freezing by the smaller cloud droplets, which can
    cause super cooled clouds to occur under colder temperatures. The possible consequences to
    radiative flux of all of the processes are outlined in Table 9-18 (top of the atmosphere effects) and
    Table 9-19 (surface radiative and precipitation effects) (Denman et al., 2007, 156394). though
    significant uncertainties remain. Nevertheless, the individual processes cannot be considered in
    isolation because of the numerous feedbacks, and because atmospheric aerosol concentrations and
    climate are intimately coupled (Denman et al., 2007, 156394; Dentener et al., 2006, 088434).
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    9.3.9.1.   Glaciers and Snowpack
    
          Organic compounds are incorporated into snow by wet and dry deposition processes (Lei  and
    Wania, 2004, 127880; Roth et al, 2004, 056431). Atmospherically deposited organics appear to be
    ubiquitous in snowpacks at appreciable concentrations (Grannas et al., 2007, 156492). Examples
    include PAHs, phthalates, alkanes, phenols, low molecular weight carbonyls, POPs, and low
    molecular weight organic acids (Halsall, 2004, 155822; Nakamura et al., 2000, 156792; Villa et al.,
    2003, 156139). Humic-like substances found in the snowpack may release VOCs into the
    atmosphere via photo-oxidation (Grannas et al., 2004, 155803; Grannas et al., 2007, 156492).
    Several thousand organic species were identified by Grannas et al. (2006, 155804). based on
    molecular weight, from a single ice core collected in Russia. Little information is available, however,
    regarding the chemical properties of these chemical constituents. In addition to the diversity of
    chemicals that are deposited into the snowpack, there are also biological organisms, including
    bacteria and algae. Their role in influencing snow chemistry and volatilization processes is not
    understood (Grannas et al., 2007, 156492).
          Recent research has explored connections between the atmosphere and the cryosphere (land or
    sea covered by snow or ice). A seasonal maximum of 40% of the Earth's land surface is covered by
    snow or ice, as well as several percent  of the oceans. Particulate deposition to snow and ice surfaces
    can affect melting rates. Deposition of PM to glacial ice surfaces can affect the subsequent rate of
    melting. A thin cover of debris contributes to accelerated melting. A thicker cover of debris, such as
    that which may result from a volcanic eruption, retards melting. The difference is due to the
    changing balance between enhanced absorption of shortwave radiation by PM and conductive heat
    flow (insulation) through a buildup of material having low heat conduction (Kirkbride  and
    Dugmore, 2003,  156645).This issue is  particularly important for deposition of large quantities of
    volcanic material. To a lesser extent, however, the same principles apply to PM deposition derived
    from air pollution. Under a thin layer of debris, ablation rates are higher than for clean ice. However,
    as the thickness of the debris layer increases, ablation rates systematically decline (Nicholson  and
    Benn, 2006, 156806). The threshold debris thickness that separates ablation increase from decrease
    is site specific and depends on local climate and the nature of the debris particles. Nicholson and
    Benn (2006, 156806) presented a surface energy  balance model to calculate ice melt beneath a
    surface debris layer, based on meteorological data and basic debris characteristics. Modeled melting
    rates matched observed rates, suggesting that the model produced useful results.
          Long-range atmospheric transport of PM delivers a large fraction of the total input of POPs to
    the Arctic region (Halsall,  2004, 155822). These  contaminants can accumulate in Arctic food webs
    and have become the focus of international research and concern. Nevertheless, fate and transport of
    POPs within terrestrial and marine Arctic ecosystems are not well understood and are strongly
    affected by the presence of snow and ice. Sea ice provides a barrier to air-water exchange, and this
    hinders volatilization and re-emission of previously deposited contaminants (Halsall, 2004, 155822).
    Thus, the effects of greenhouse gasses  and PM on climate in the Arctic region have feedbacks to
    POP fate, transport, and toxicity. The transfer of POPs among the major abiotic environmental
    compartments in the Arctic are summarized in Figure 9-84 from Halsall (2004, 155822). Recent
    studies detailing  rate and transport of POPs are summarized in Table 9-20.
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    Table 9-20.   Recent studies highlighting POP occurrence and fate in the major arctic compartments.
    ATMOSPHERE
    1 Annual time-series of OC and PCB concentrations in the Norwegian Arctic
    2 Long-term analysis of the chlordane-group and their input to the Arctic with changing sources
    3 PAH occurrence at monitoring sites across the Arctic, seasonality and gas/particle partitioning
    4 PCB occurrence at monitoring sites across the Arctic, spatial differences and seasonality
    5 Long-term analysis of PCB and OC trends in the Canadian Arctic and seasonal patterns
    6 Trans-Pacific LRAT and impact of Asian sources on the western Canadian Arctic
    Oehmeetal. (1996, 1560011
    Bidleman et al. (2002, 155691)
    Halsalletal. (1997, 155821)
    Stern etal. (1997, 1560961
    Hung et al. (2001, 155856: 2002, 1558571
    Bailey et al. (2000, 1556701
    FRESHWATER
    7 Annual avg water concentrations in major Russian rivers for selected OC pesticides
    8 Long-term (decades) PCB deposition profile in Arctic lake sediments
    9 Mass balance of selected DCs in Canadian Arctic lake conducted with data collected over 3 yrs
    10 Examining the biodegradation of HCHs in Canadian Arctic watersheds
    Alexeeva et al. (2001, 155651)
    Muir etal. (1996,155991)
    Helm et al. (2002, 155835)
    Helm et al. (2000, 155834)
    MARINE
    1 1 Transport and entry of (3-HCH into western Arctic Ocean via Pacific surface waters
    1 2 Occurrence of current use pesticides in air, fog and surface seawater in the western Arctic Ocean
    13 Resolving petrogenic and anthropogenic PAH input to marine sediments in coastal Arctic seas
    14 Quantifying abiotic and biotic degradation of HCHs in the Arctic Ocean water column
    15 PCBs and DCs in surface ocean water— Bering and Chukchi seas
    16 Spatial patterns of HCHs and toxaphene in Arctic Ocean surface water
    Li et al. (2002, 156691)
    Chermyak etal. (1996, 155726)
    Yunker etal. (1996, 1561751
    Harner et al. (2000, 1558291
    Strachan etal. (2001, 1561031
    Jantunen and Bidleman (1998, 155877)
    SNOW/AIR-FRESHWATER
    17 PAHs (and inorganics) in surface snow layers (snowpit) at Summit, Greenland
    18 PAHs measured in snow and ice layers on Agassiz ice-cap, Ellesmere Island, Canada
    19 Modeling OC behaviour and fate in the surface seasonal snow pack at Amituk Lake, Canada
    20 DCs, PCBs and PAHs in snow and ice of the Ob-Yenisey watershed of the Russian Arctic
    Masclet et al. (2000, 1559661
    Peters etal. (1995, 156856)
    Wania etal. (1998, 156148)
    Melnikov et al. (2003, 1567531
    OCEAN/AIR
    21 Transfer of a-HCH across the air/water interface in the western Arctic ocean
    22 Calculated seasonality of OC air/water fluxes in the Canadian high Arctic
    Jantunen and Bidleman (1996, 155876)
    Hargrave etal. (1997, 155827)
    OCEAN/ICE
    23 Transport potential of contaminants across the Arctic ocean via sea-ice drift
    24 The importance of eastern Arctic sea-ice drift as a source of contaminants to the Norwegian sea
    Pfirman etal. (1997, 156864)
    Korsnes et al. (2002, 156657)
                                                               Source: Reprinted with Permission of Elsevier Ltd. from Halsall (2004,15582:
    December 2009
    9-161
    

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     LRAT
                                                Atmosphere
                                                                   (21-22)
                             Snow/ice caps
                                         TTTrnn
                             Terrestrial    po>
                             Catchment r.
                                         rivers
    (Ii-24.)
    Snow/ sea ice
    n
    
    L. (1M6) l>?
    p> Suriace E
    Ocean m
    vl
    9
    Deep Ocean
    \
    j
    **g
    
    -------
               for the BC on snow RF of +0.10 ± 0.10 W/m2, with a low level of scientific understanding
               (Section 2.9, Table 2.11, of the IPCC AR4).
    
    
    9.3.9.3.   Effects on  Local and Regional Climate
    
          Most effects of PM on climate, as assessed by IPCC (Stohl et al., 2007, 157015) and
    summarized in this assessment, focus on global-scale processes and responses. In addition, it is also
    possible that PM emissions contribute to local and regional climate changes. These might include
    short-term cycles in rainfall or temperature and rainfall suppression, especially near cities and for
    orographic precipitation. Rainfall suppression, in particular, is believed to exacerbate water supply
    problems which are substantial in many regions, especially in the western U.S.
          Aerosol particles, directly and through cloud enhancement, may reduce near-surface wind
    speeds locally. Slower winds, in turn, reduce evaporation. The overall impact can be a reduction in
    local precipitation. Jacobson and Kaufman (2006, 090942) investigated the effects of PM on
    spatially-distributed wind speeds and resulting feedbacks to precipitation using the
    GATOR-GCMOM (Jacobson, 2001, 155864) and supporting evidence from satellite data. The study
    focused on the South Coast Air Basin (SCAB) in California during February and August, 2002-2004.
    The modeled precipitation decrease over land in California was 2% of the baseline 1.5  mm/day due
    to emissions of anthropogenic aerosol particle and precursor gasses in the SCAB domain. However,
    the reduction over much of the Sierra Nevada, where most precipitation falls, was  up to 0.5 mm/day,
    or 4-5% of the baseline 10-13 mm/day in that mountainous region (Jacobson, 2006, 156599). The
    probable mechanism was described as follows. Aerosol particles and  aerosol-enhanced clouds reduce
    wind speeds below them by stabilizing the  air, reducing the vertical transport of horizontal
    momentum. In turn, the reduced wind speeds, and  associated reduced evaporation and increased
    cloud lifetime, contributes to reduced local and regional precipitation (Jacobson, 2006, 156599).
          Effects of air pollution on regional precipitation were quantified by Givati and Rosenfeld
    (2004, 156475). They found a 15-25% reduction in the orographic component of precipitation
    downwind of major coastal urban areas during the 20th century. Their study focused on
    orographically-forced clouds because these short-lived, shallow clouds are expected to exhibit the
    largest effect of air pollution on precipitation. Substantially larger precipitation suppression due to
    aerosol participate pollution was found between Fresno and Sacramento in California by Givati and
    Rosenfeld (2004, 156475). Precipitation losses over topographical barriers in the Sierra Nevada
    amounted to 15-25% of the annual precipitation at elevations less than 2,000 m. This precipitation
    suppression occurred mainly in the relatively shallow orographic clouds within the cold air mass of
    cyclones. The suppression that occurred on the upslope side of the mountains was  coupled with
    similar percentage (but lower absolute volume) enhancement on the drier downslope eastern side
    (Givati and Rosenfeld, 2004, 156475). Similar results were found in studies by Griffith et al. (2005,
    156497). Jirak and Cotton (2006, 156612). Rosenfeld and Givati (2006, 156924). and Rosenfeld et
    al. (2007,  156057). At all of these study locations (California, Israel,  Utah, Colorado, China),
    orographic precipitation decreased by 15-30% downwind of pollution sources, likely due to creation
    of more and smaller cloud droplets and resulting suppression of precipitation.
          The study of Givati and Rosenfeld (2004, 156475) was the first to quantify the microphysical
    effect of mesoscale precipitation. Following the findings  of Givati and Rosenfeld (2004, 156475).
    the effects of aerosol air pollution on precipitation at high elevation sites in the Front Range of
    Colorado adjacent to urban areas were investigated by Jirak and Cotton (2006, 156612).
    Examination of precipitation trends showed that the ratio of upslope precipitation during easterly
    flows at high elevation west of Denver and Colorado Springs to the upwind urban sites decreased by
    about 30% over the  past half century. These results provide further support for the hypothesis that
    aerosol pollution suppresses orographic precipitation downwind of pollution source areas.
          Griffith et al. (2005, 156497) found similar reductions in mountainous precipitation in Utah,
    downwind of Salt Lake City and Provo. The ratio of precipitation at mountain stations located in
    rural settings in Utah and Nevada remained stable, supporting the hypothesis that air pollution
    decreases Ro (the ratio of precipitation at the downwind site to precipitation at the upwind pollution
    source) over the mountains to the east of Salt Lake City.
          Rosenfeld and Givati (2006, 156924) extended the investigation of the suppression of
    precipitation by aerosol pollutants to a larger scale by examining the  ratio between precipitation
    amounts over the hills to precipitation over upwind lowland areas throughout the western U.S. from
    the Pacific Coast to the Rocky Mountains. They found in these paired analyses a pattern of
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    decreasing precipitation by as much as 24% from the Mexican border to central California, with no
    decrease in northern California and Oregon and smaller decrease of 14% in Washington east of
    Seattle and Puget Sound. Similar decreases were found over Arizona and New Mexico (Rosenfeld,
    2006, 190233). Utah (Griffith et al., 2005, 156497). and the east slope of the Colorado Rockies
    (Jirak and Cotton, 2006, 156612).
          Suppression of winter orographic precipitation appears to occur up to hundreds of kilometers
    inland of coastal urban areas (Rosenfeld, 2006, 190233). Decreases in this precipitation ratio
    occurred during winter orographic precipitation, but not during convective summer precipitation
    over the same mountain ranges. This finding agrees with the expectation that aerosol-induced
    changes in the rate of precipitation formation would cause a decrease in precipitation from shallow
    and short-lived orographic clouds, but not necessarily from deeper and longer-lived thermally-driven
    convective clouds.
          Results of these studies of aerosol effects on orographic precipitation suggest that
    human-caused air pollution, and fine particles in particular, have had a large effect on precipitation
    well beyond the local scales of the pollution sources (Rosenfeld, 2006, 190233).
    
    
    9.3.10.Summary of Effects on Climate
    
          Aerosols affect climate through direct and indirect effects. The direct effect is primarily
    realized as planet brightening when seen from space because most aerosols scatter most of the
    visible spectrum light that reaches them. The IPCC AR4 reported that the radiative forcing from this
    direct effect was -0.5 (±0.4) W/m2 and identified the level  of scientific understanding of this effect as
    'Medium-low'. The global mean direct radiative forcing effect from individual components of
    aerosols was estimated for the first time in the IPCC AR4 where they  were reported to be (all in
    W/m2 units): -0.4 (±0.2) for sulfate, -0.05 (±0.05) for fossil fuel-derived organic carbon, +0.2 (±0.15)
    for fossil fuel-derived black carbon, +0.03 (±0.12) for biomass burning, -0.1 (±0.1) for nitrates, and
    -0.1  (±0.2) for mineral dust. Global loadings of anthropogenic  dust and nitrates remain very
    troublesome to estimate, making the radiative forcing estimates for these constituents particularly
    uncertain.
          Numerical modeling of aerosol effects on climate has sustained remarkable progress since the
    time of the last PM AQCD, though model solutions still display large heterogeneity in their estimates
    of the direct radiative forcing effect from anthropogenic aerosols. The clear-sky direct radiative
    forcing over ocean due to anthropogenic aerosols  is estimated from satellite instruments to be on the
    order of-1.1 (±0.37) W/m2 while model estimates are -0.6 W/m2. The models' low bias over ocean is
    carried through for the global average: global average direct radiative forcing from anthropogenic
    aerosols is estimated from measurements to range from -0.9 to -1.9 W/m2, larger than the estimate of
    -0.8  W/m2 from the models.
          Aerosol indirect effects on climate are primarily realized as an increase in cloud brightness
    (termed the 'first indirect' or Twomey effect), changes in precipitation, and possible changes in cloud
    lifetime. The IPCC AR4 reported that the radiative forcing from the Twomey effect was -0.7 (range:
    -1.1  to +4) and identified the level of scientific understanding of this effect as 'Low' in part owing to
    the very large unknowns concerning aerosol size distributions and important interactions with
    clouds. Other indirect effects from aerosols are not considered  to be radiative forcing.
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          Taken together, direct and indirect effects from aerosols increase Earth's shortwave albedo or
    reflectance thereby reducing the radiative flux reaching the surface from the Sun. This produces net
    climate cooling from aerosols. The current scientific consensus reported by IPCC AR4 is that the
    direct and indirect radiative forcing from anthropogenic aerosols computed at the top of the
    atmosphere, on a global average, is about -1.3 (range: -2.2 to -0.5) W/m2. While the overall global
    average effect of aerosols at the top of the atmosphere and at the surface is negative, absorption and
    scattering by aerosols within the atmospheric column warms the atmosphere between the Earth's
    surface and top of the atmosphere. In part, this is owing to differences in the distribution of aerosol
    type and size within the vertical  atmospheric column since aerosol type and size distributions
    strongly affect the aerosol scattering and reradiation efficiencies  at different altitudes and
    atmospheric temperatures. And,  although the magnitude of the overall negative radiative forcing at
    the top of the atmosphere appears large in comparison to the analogous IPCC AR4 estimate of
    positive radiative forcing from anthropogenic GHG of about +2.9 (± 0.3) W/m2, the horizontal,
    vertical, and temporal distributions and the physical  lifetimes of these two very different radiative
    forcing agents are not similar; therefore, the effects do not simply off-set one another.
          Overall, the evidence is sufficient to conclude that a causal relationship exists between
    PM and effects on climate, including both direct effects on radiative forcing and indirect
    effects that involve cloud feedbacks that influence precipitation formation and cloud
    lifetimes.
    9.4.  Ecological  Effects  of PM
    9.4.1.  Introduction
    
          PM is heterogeneous with respect to chemical composition and size; therefore, it can cause a
    variety of ecological effects, which have been previously described by the U.S. EPA (2004, 056905)
    and by Grantz et al. (2003, 155805). Atmospheric PM has been defined, for regulatory purposes,
    mainly by size fractions and less clearly so in terms of chemical nature, structure, or source. Both
    fine and coarse-mode particles may affect plants and other organisms; however, PM size classes do
    not necessarily relate to ecological effects (U.S. EPA, 1996, 079380). More often the chemical
    constituents drive the ecosystem response to PM (Grantz et al., 2003, 155805).
          The previous PM assessment (U.S. EPA, 2004, 056905) included the acidifying effects  of
    particulate N and S. The 2008 NOXSOX ISA (U.S. EPA, 2008, 157074) assessed the effects of
    particle- and gas-phase N and S pollution on acidification, N enrichment,  and Hg methylation.
    Acidification of ecosystems is driven primarily by deposition resulting from SOX, NOX, and NHX
    pollution. Acidification from the deposition resulting from current emission levels causes a cascade
    of effects that harm susceptible aquatic and terrestrial ecosystems, including slower growth and
    injury to forests and localized extinction of fishes and other aquatic species. In addition to
    acidification, atmospheric deposition of reactive N resulting from current NOX and NHX emissions
    along with other non-atmospheric sources (e.g., fertilizers and wastewater), causes a suite of
    ecological changes within sensitive ecosystems. These include increased primary productivity in
    most N-limited ecosystems, biodiversity losses, changes in C cycling, and eutrophication and
    harmful algal blooms in freshwater, estuarine, and ocean ecosystems. In some watersheds, additional
    SO42~ from atmospheric deposition increases Hg methylation rates by increasing both the number
    and activity of S-reducing bacteria. Methylmercury is a powerful toxin that can bioaccumulate to
    toxic amounts in food webs at higher trophic levels.
          This assessment of PM effects on ecosystems considers both direct and indirect exposure
    pathways. Atmospheric PM may affect ecological receptors directly following deposition on surfaces
    or indirectly by changing the soil chemistry or by changing the amount of radiation reaching the
    Earth's surface. Indirect effects acting through the soil are often thought to be most  significant
    because they can alter nutrient cycling and inhibit nutrient uptake (U.S. EPA, 2004, 056905;
    U.S. EPA, 2008, 157074). The U.S. EPA (2004, 056905) reported that the effects of PM can be both
    chemical and physical. Physical effects of particle deposition on vegetation may include abrasion
    and radiative heating. However, chemical effects may be more significant (U.S. EPA, 2008, 157074).
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          In general, anthropogenic stressors can result in damaged ecosystems that do not recover
    readily (Odum, 1993, 076742; Rapport and Whitford, 1999, 004595). Ecosystems sometimes lack
    the capacity to adapt to an anthropogenic stress and are unable to maintain their normal structure and
    functions unless the stressor is removed (Rapport and Whitford, 1999, 004595). These stresses
    result in a process of ecosystem degradation marked by a decrease in biodiversity, reduced primary
    and secondary production, and a lower capacity to recover and return to the original ecosystem state.
    In addition, there can be an increased prevalence of disease, reduced nutrient cycling, increased
    dominance of exotic species, and increased dominance by smaller, short-lived opportunistic species
    (Odum, 1985, 039482; Rapport  and Whitford, 1999, 004595).
          Ecosystems are often subjected to multiple stressors, of which atmospheric PM deposition is
    only one. Additional stressors are also important, including O3 exposure, climatic variation, natural
    and human disturbance, the occurrence of invasive non-native plants, native and non-native insect
    pests, disease, acidification, and eutrophication among others. PM deposition interacts with these
    other stressors to affect ecosystem patterns and processes.
          The possible effects of particulate (and other) air pollutants on ecosystems have been
    categorized by Guderian (1977,  004150) as follows:
    
            •   accumulation of pollutants in plants and other ecosystem components (such as soil and
               surface- and groundwater),
    
            •   damage to consumers as a result of pollutant accumulation,
    
            •   changes in species diversity because of shifts in competition,
    
            •   disruption of biogeochemical cycles,
    
            •   disruption of stability and reduction in the ability to self-regulate,
    
            •   breakdown of stands and associations, and
    
            •   expansion of denuded zones.
    
          The general conclusion of the last PM assessment (U.S. EPA, 2004, 056905) was that
    ecosystem response to PM can be difficult to determine because the changes are often subtle. For
    example, changes in the soil may not be observed until pollutant deposition has occurred for many
    decades, except in the most severely polluted areas around heavily industrialized point sources. The
    presence of co-occurring pollutants generally makes it difficult to attribute ecological effects to PM
    alone or to one constituent in the deposited PM. In other words, the potential for alteration of
    ecosystem function and structure exists but can be difficult to quantify except in cases of extreme
    amounts of deposition, especially when there are other pollutants present in the ambient air that may
    produce additive or synergistic responses.
          New information on the ecological effects of coarse and fine particle PM is presented in the
    following discussion in the context of effects that were known from the last PM AQCD (U.S. EPA,
    2004, 056905). The general effects of the chemical constituents of PM are discussed; however, a
    rigorous assessment of each chemical constituent (e.g., Hg, Cd, Pb, etc.) is not given. Both direct and
    indirect effects will be discussed and the strength of the scientific evidence will be evaluated using
    the causality framework.
    
    
    9.4.1.1.  Ecosystem Scale, Function, and Structure
    
          Information presented in this section was collected at multiple scales, ranging from the
    physiology of a given species to population, community, and ecosystem-level investigations. For this
    assessment, "ecosystem" is defined as a functional entity consisting of interacting groups of living
    organisms and their abiotic (chemical and physical) environment. Ecosystems cover a hierarchy of
    spatial scales and can comprise the entire globe, biomes at the continental scale, or small, well-
    circumscribed systems such as a small pond.
          Ecosystems have both structure and function. Structure may refer to a variety of measurements
    including the species richness, abundance, community composition and biodiversity as well as
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    landscape attributes. Competition among and within species and their tolerance to environmental
    stresses are key elements of survivorship. When environmental conditions are shifted, for example,
    by the presence of anthropogenic air pollution, these competitive relationships may change and
    tolerance to stress may be exceeded. "Function" refers to the suite of processes and interactions
    among the ecosystem components and their environment that involve nutrient and energy flow as
    well as other attributes including water dynamics and the flux of trace gases. Plant processes
    including photosynthesis, nutrient uptake, respiration, and C allocation, are directly related to
    functions of energy flow and nutrient cycling. The energy accumulated and stored by vegetation (via
    photosynthetic C capture) is available to other organisms. Energy moves from one organism to
    another through food webs, until it is ultimately released as heat. Nutrients and water can be
    recycled. Air pollution alters the function of ecosystems when elemental cycles or the energy flow
    are altered. This alteration can also be manifested in changes in the biotic composition of
    ecosystems.
          There are at least three levels of ecosystem response to pollutant deposition: (1) the individual
    organism and its environment; (2) the population and its environment; and (3) the biological
    community composed of many species and their environment (Billings, 1978, 034165). Individual
    organisms within  a population vary in their ability to withstand the stress of environmental change.
    The response of individual organisms within a population is based on their genetic constitution, stage
    of growth at time  of exposure to stress, and the microhabitat in which they are growing (Levine and
    Pinto, 1998, 029599).  The range within which organisms can exist and function determines the
    ability of the population to survive. Those able to cope with the  stresses survive and reproduce.
    Competition among different species results in succession (community change over time) and,
    ultimately, produces ecosystems composed of populations of species that have the capability to
    tolerate the stresses (Guderian, 1985, 019325: Rapport and Whitford, 1999, 004595). Available
    information on individual, population and community response to PM will be discussed.
    
    
    9.4.1.2.   Ecosystem Services
    
          Ecosystem structure and function may be translated into ecosystem services. Ecosystem
    services identify the varied and numerous ways that ecosystems are important to human welfare.
    Ecosystems provide many goods and services that are of vital importance for the functioning of the
    biosphere and provide the basis  for the delivery of tangible benefits to human society. Hassan et al.
    (2005, 092759) define these to include supporting, provisioning, regulating, and cultural services:
    
           •   Supporting services  are necessary for the production of all other ecosystem services.
               Some  examples include biomass production, production of atmospheric O2, soil
              formation and retention, nutrient cycling, water cycling, and provisioning of habitat.
              Biodiversity is a supporting service that is increasingly  recognized to  sustain many of the
              goods and services that humans enjoy from ecosystems. These provide a basis for three
              higher-level categories of services.
    
           •  Provisioning services, such as products (Gitay et al., 2001, 092761), i.e., food (including
              game, roots, seeds, nuts and other fruit, spices, fodder), fiber (including wood, textiles),
              and medicinal and cosmetic products (including aromatic plants, pigments).
    
           •  Regulating services that are of paramount importance for human society such as (a) C
              sequestration, (b) climate and water regulation,  (c) protection from natural hazards such
              as floods, avalanches, or rock-fall, (d) water and air purification, and (e) disease and pest
              regulation.
    
           •  Cultural services that satisfy human spiritual and aesthetic appreciation  of ecosystems
              and their components.
    9.4.2.  Deposition  of PM
          Deposition of PM is discussed in Chapter 3.3.4. Additional material specifically related to
    ecosystems is discussed in this section.
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    9.4.2.1.   Forms of Deposition
    
          Research summarized by the previous NAAQS PM assessment illustrated the complexity of
    deposition processes. Airborne particles, their gas-phase precursors, and their transformation
    products are removed from the atmosphere by wet and dry deposition processes. These deposition
    processes transfer PM pollutants to other environmental media where they can alter the structure,
    function, diversity, and sustainability of complex ecosystems. Dry deposition of PM is most effective
    for coarse particles. These include primary geologic materials and elements such as iron and
    manganese. By contrast, wet deposition is more effective for fine particles of secondary atmospheric
    origin and elements such as cadmium, chromium, lead, nickel, and vanadium (Reisinger, 1990,
    046737: Smith, 1990, 084015; U.S. EPA, 2004, 056905). The relative magnitudes of the different
    deposition modes vary with ecosystem type, location, elevation, and chemical burden of the
    atmosphere (U.S. EPA, 2004, 056905). There are differences in the deposition behavior of fine and
    coarse particles. Coarse particles generally settle nearer their site of formation than do fine particles.
    In addition, the chemical constitution of individual particles is correlated with size. For example,
    much of the base cation and heavy metal burden is present on coarse particles.
          Fine PM is often a secondary pollutant that forms within the atmosphere, rather than being
    directly emitted from a pollution source. It derives from atmospheric gas-to-particle conversion
    reactions involving nucleation, condensation, and coagulation, and from evaporation of water from
    contaminated fog and cloud droplets. Fine PM may also contain condensates of VOCs, volatilized
    metals, and products of incomplete combustion, including poly cyclic aromatic hydrocarbons (PAH)
    and BC (soot) (U.S. EPA, 2004, 056905).
          Fine PM may act as a carrier for materials such as herbicides that are phytotoxic. Fine PM
    provides much of the surface area of particles suspended in the atmosphere, whereas coarse PM
    provides much of the mass of airborne particles.  Surface area can influence ecological effects
    associated with the oxidizing capacity of fine particles, their interactions with other pollutants, and
    their adsorption of organic compounds. Fine and coarse particles also respond to changes in
    atmospheric humidity, precipitation, and wind, and these can alter their deposition characteristics.
          Coarse PM is mainly a primary pollutant, having been emitted from pollution sources as fully
    formed particles derived from abrasion and crushing processes, soil disturbances, desiccation of
    marine aerosol emitted from bursting bubbles, hygroscopic fine PM expanding  with humidity to
    coarse mode, and/or gas condensation directly onto preexisting coarse particles. Suspended primary
    coarse PM may contain iron, silica, aluminum, and base cations from soil, plant and insect
    fragments, pollen, fungal spores, bacteria, and viruses, as well as fly ash, brake  lining particles,  and
    automobile tire fragments. Coarse mode particles can be altered by chemical reactions and/or
    physical interactions with gaseous or liquid contaminants.
          Exposure to a given mass concentration of PM may lead to widely differing phytotoxic and
    other environmental outcomes depending upon the particular mix of PM constituents involved.
    Especially important in this regard are S and N components of PM, which are addressed in the 2008
    NOXSOX ISA, and effects  of particulate heavy metals and organic contaminants. This variability has
    not been characterized adequately. Though effects of specific  chemical fractions of PM have been
    described to some extent, there has been relatively little research aimed at defining the effects of
    unspeciated PM on plants or ecosystems.
    
    
    9.4.2.2.   Components of PM Deposition
    
    
    
          Trace Metals
    
          Atmospheric deposition can be the primary source of some metals to some watersheds.  Metal
    inputs can include the primary crustal elements (Al, Ca, K, Fe, Mg, Si, Ti) and the primary
    anthropogenic elements (Cu, Zn, Cd, Cr, Mn, Pb, V, Hg). The crustal elements are derived largely
    from weathering and erosion, whereas the anthropogenic elements are derived from combustion,
    industrial sources, and other man-made sources (Goforth and Christoforou, 2006, 088353).
          Heavy metal deposition to ecosystems depends on their location as  well as upwind emissions
    source strength. The deposition velocity tends to be dependent on particle size and chemical species.
    Larger particles deposit more efficiently than smaller particles. Heavy metals preferentially associate
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    with fine particles. Fine particles also have the longest atmospheric residence times. Depending on
    climate and topography, fine particles may remain airborne for days to months and may be
    transported thousands of kilometers from their source.
          Ecosystems immediately downwind of major heavy metal emissions sources may receive
    locally heavy dry deposition. Trace element investigations conducted in roadside, industrial, and
    urban environments have also  shown that substantial amounts of particulate heavy metals can
    accumulate on surfaces.
          A significant trace metal component of PM is mercury (Hg). Hg is toxic and can move readily
    through environmental compartments. Atmospheric and depositional inputs of Hg include both
    natural and anthropogenic sources. Natural geologic contributions to Hg in the environment include
    geothermal and volcanic activity, geologic metal deposits, and organic-rich sedimentary rocks. These
    natural emissions combine with anthropogenic emissions from such sources as power plants,
    landfills, sewage sludge, mine waste, and incineration (Gustin, 2003,  155816; Schroeder and
    Munthe, 1998, 014559). Emissions from natural sources are controlled by geologic features,
    including substrate Hg content, rock type, the degree of hydrothermal activity, and the presence of
    heat sources (Gustin, 2003, 155816). The significance of natural Hg sources relative to
    anthropogenic sources varies geographically. For example, Nevada occurs within a global
    mercuriferous belt, with area emissions about three times higher than the value assumed for global
    modeling (Gustin, 2003, 155816). In Nevada, natural and anthropogenic Hg emissions are
    approximately equal (Gustin, 2003, 155816).
          The U.S. EPA (1997,  157066) compiled an assessment of the sources and environmental
    effects of Hg in the U.S. A variety of factors were found to influence Hg deposition, fate and
    transport (Table 9-21). Such factors relate in particular to speciation of the Hg that is emitted, the
    forms in which it is deposited from the atmosphere, and transformations that occur within the
    atmosphere and within the aquatic, transitional, and terrestrial compartments of the receiving
    watershed. There have been studies that have reconstructed, from lake sediment records, the
    atmospheric depositional history of trace metals and PAHs in lakes adjacent to coal-fired power
    plants. For example, Donahue  et al. (2006, 155751) analyzed sediment from Wababun Lake, which
    is located in  Alberta, Canada in proximity (within 35 km) to 4 power plants built since 1950. Trace
    metal concentrations of Hg,  Cu, Pb, As, and Se in lake sediment increased by 1.2- to 4-fold. The
    total PAH flux to surface sediments was 730-1,100 ug/m2/yr, which was two to five times higher
    than in 2 lakes situated 20 km to the north and 70 km to the south. Further discussion of Hg effects
    on ecosystems can be found in Section 9.4.5.
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    Table 9-21.   Factors potentially important in estimating Hg exposure.
                  Factor
                    Importance and Possible Effect on Mercury Exposure
    Type of anthropogenic source of mercury
    Mercury emission rates from stack
    Different combustion and industrial process sources are anticipated to have different local scale impacts due to
    physical source characteristics (e.g., stack height), the method of waste generation (e.g., incineration or mass
    burn) or mercury control devices and their effectiveness.
    
    Increased emissions will result in a greater chance of adverse impacts on environment.
    Mercury species emitted from stack
    More soluble species will tend to deposit closer to the source.
    Form of mercury emitted from stack
    Transport properties can be highly dependent on form.
    Deposition differences between vapor and
    particulate-bound mercury
    Vapor-phase forms may deposit significantly faster than particulate-bound forms.
    Transformations of mercury after emission from
    source
    Relatively nontoxic forms emitted from source may be transformed into more toxic compounds.
    Transformation of mercury in watershed soil
    Reduction and revolatilization of mercury in soil limits the buildup of concentration.
    Transport of mercury from watershed soils to
    water body
    Mercury in watershed soils can be a significant source to water bodies and subsequently to fish.
    Transformation of mercury in water body
    Reduction, methylation, and demethylation of mercury in water bodies affect the overall concentration and the
    MHg fraction, which is bioaccumulated in fish.
    Facility locations
    Effects of meteorology and terrain may be significant.
    Location relative to local mercury source
    Receptors located downwind are more likely to have higher exposures. Influence of distance depends on source
    type.
    Contribution from non-local sources of mercury   Important to keep predicted impacts of local sources in perspective.
    Uncertainty
    Reduces confidence in ability to estimate exposure accurately.
                                                                                 Source: Modified from U.S. EPA (1997,157066)
           Organics
    
           Organic compounds that may be associated with deposited PM include persistent organic
    pollutants (POPs), pesticides, SOCs, polyaromatic hydrocarbons (PAHs) and flame retardants among
    others. Organic compounds partition between gas and particle phases, and organic particulate
    deposition depends largely on the particle sizes available for adsorption (U.S. EPA, 2004, 056905).
    Dry deposition of organic materials is often dominated by the coarse fraction. Gas-particle phase
    interconversions are important  in determining the amount of dry deposition.
           Most persistent organic pollutants (POPs) enter the biosphere via human activities, including
    synthetic pesticide application, output of poly chlorinated dibenzo dioxins (PCDD) from incinerators,
    and accidental release of PCBs from transformers (Lee, 2006, 088968). Once they are introduced
    into the environment, their accumulation and magnification in biological systems are determined by
    physiochemical properties and environmental conditions (Section 9.4.6). Uptake by plants can occur
    at the soil/plant interface and at the air/plant interface (Krupa et al., 2008, 198696). For lipophilic
    POPs, such as PCDDs and PCBs, the air/plant response route generally dominates (Lee, 2006,
    088968; Thomas et al., 1998, 156118). but uptake through above-ground plant tissue  also occurs. In
    a study of zucchini (Cucurbita pepo), Lee et al. (2006, 088968) found chlordane pesticide
    components in all vegetation tissues examined: root, stem, leaves, fruits.
          Many pesticides and SOCs are carcinogenic or estrogenic and pose potential threats to aquatic
    and terrestrial biota. Although deposition of SOCs was previously reported for the Sierra Nevada
    Mountains in California and the Rocky Mountains in Colorado, little was previously known about
    the occurrence, distribution, or sources of SOCs in alpine, sub-Arctic, and Arctic ecosystems in the
    western U.S. The snowpack is efficient at scavenging of both particulate and gas phase pesticides
    from the atmosphere (Halsall, 2004, 155822: Lei  and Wania, 2004,  127880). Analysis of pesticides
    in snowpack samples from seven NPs in the western U.S. by Hageman et al. (2006, 156509)
    illustrated the deposition and fate of 47 pesticides and their degradation products. Correlation
    analysis with latitude, temperature, elevation, PM, and two indicators of regional pesticide use
    suggested that regional patterns in historic and current agricultural practices are largely responsible
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    for the distribution of pesticides in the NPs. Pesticide deposition to parks in Alaska was attributed to
    long-range atmospheric transport.
          PAHs include hundreds of different compounds that are characterized by possessing two or
    more fused benzene rings. They are widespread contaminants in the environment, and are formed by
    incomplete combustion of fossil fuels and other organic materials. Eight PAHs are considered
    carcinogenic and 16 are classified by EPA as priority pollutants. They are common air pollutants in
    metropolitan areas, derived from vehicular traffic and other urban sources. Especially high
    concentrations have been found near Soderberg aluminum production industries and areas where
    heating during winter via wood burning is common. Other sources, in addition to gasoline and diesel
    engines, include forest fires and various forms of fossil fuel combustion (Sanderson and Farant,
    2004, 1569421
          The behavior of PAHs is strongly determined by their chemical characteristics, especially their
    nonpolarity and hydrophobicity. They readily adsorb to particulates in the air and to sediments in
    water. Srogi (2007, 180049) provided a thorough review of PAH concentrations in various
    environmental compartments and their use for assessing  environmental risks and possible effects on
    ecosystems and human health.
          Deposition and fate of PAH has been an important area of research. Because they are
    carcinogenic, PAHs are important environmental contaminants. Root-soil behavior of PAHs is an
    area of active study. Soil-bound PAHs are associated with soil organic matter and  are therefore
    generally not easily available for root uptake. PAHs are readily adsorbed to root surfaces but there
    seems to be little movement to the interior of the root or  movement up to the shoots (Gao and Zhu,
    2004, 155782). Paddy rice is the main food crop planted in China. As an aquatic plant having aerial
    roots, the movement of PAHs into rice roots may be different than their movement into more widely
    studied land-grown food crops. PAH concentrations in the rice roots were more correlated with the
    water and air compartments than with the soil (Jiao et al, 2007,  155879).
          The total PAH concentration in grasses adjacent to a highway have been measured to be about
    eight times higher than in grasses from reference sites not close to a highway (Crepineau et al., 2003,
    155741). Howe et al. (2004,  155854) found that concentrations of PAHs and hexachlorobenzene
    (HCB) in spruce (Picea spp.) needles at 36 sites in eastern Alaska varied by an order of magnitude.
    Samples collected near the city of Fairbanks generally had higher concentrations than samples
    collected from rural areas. The relative importance of combustion sources versus petrogenic sources
    was highest in the near-coastal areas, as reflected in variation in the concentration of ratios of
    isomeric PAHs.
          Use of flame retardants has increased in recent years in response to fire product safety
    regulations. However, some flame retardant chemicals are toxic and are readily transported
    atmospherically. Use of some has been banned in Europe and some of the United States because of
    their persistence and tendency to bioaccumulate (Hoh et  al., 2006, 190378).
    
    
          Base Cations
    
          With respect to ecosystem effects from PM deposition, the inclusion of base cations
    (especially Ca, Mg, and K) in atmospheric deposition is generally considered to be a positive effect.
    Base cations are important plant nutrients that are in some locations present in short supply and that
    are further depleted by the acidic components of deposition. Increased base cation deposition can
    help to ameliorate adverse effects of acidification of soils and surface waters and reduce the toxicity
    of inorganic Al to plant roots and aquatic biota. These topics  are covered in detail  in the recent 2008
    NOxSOx ISA (U.S. EPA, 2008, 157074).
          Although the effects of base cation deposition inputs to terrestrial ecosystems are most
    commonly considered to be positive, under very high base cation deposition, plant health can be
    adversely affected. Dust that is high in base cations can settle on leaves and other plant structures
    and remain for extended periods of time. This is especially likely in arid environments because
    rainfall can serve to wash dry deposited materials off the foliage. Extended dust coverage can result
    in a variety of adverse impacts on plant physiology (Grantz et al., 2003,  155805).  For example, van
    Heerden et al. (2007, 156131) documented decreased chlorophyll content, inhibition of CO2
    assimilation, and uncoupling of the oxygen-evolving complex in desert shrubs exposed to high
    limestone dust deposition near a limestone quarry in Namibia.
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          Based on the Integrated Forest Study (IPS) data, the U.S. EPA (2004, 056905) concluded that
    particulate deposition has a greater effect on base cation inputs to soils than on base cation losses
    associated with the inputs of sulfur, nitrogen, and H+. These atmospheric inputs of base cations have
    considerable significance, not only to the base cation status of these ecosystems, but also to the
    potential of incoming precipitation to acidify or alkalize the soils in these ecosystems. This topic is
    discussed in detail in the recent NOXSOX ISA (U.S. EPA, 2008,  157074).
    
    
    9.4.2.3.   Magnitude of Dry Deposition
    
    
          Using Vegetation for Estimating Atmospheric Deposition
    
          Whereas direct real-time measurement of deposition or air concentrations of atmospheric
    contaminants is desirable, it is not always practical (Howe et al., 2004, 155854). Instead, passive
    time-integrative methods are frequently used. These can involve analysis of vegetative tissues as a
    record of pollutant exposure, or analysis of lake sediment cores or ice cores to determine changes in
    pollutant input over time. There is a general assumption that the concentration of an analyte in
    vegetation reflects the time-integrated concentration of that analyte in the air. The development of
    deposition layers in sediment or ice cores allows the possibility of determining the effects of changes
    in the atmospheric concentration over periods of years, decades, or longer.
          Biomonitoring methods are important in air pollution assessment and provide a complement
    for more typical instrumental analyses. It is well known that mosses can accumulate large amounts
    of heavy metals in response to atmospheric deposition.  Mosses accumulate dissolved materials and
    PM deposited from the atmosphere and have been used extensively in Europe as surrogate collectors
    for estimating bulk (wet plus dry) deposition of metals. The ease and low cost of this  method has
    enabled regional assessments to be conducted throughout Europe.
          Despite its wide use, however, several papers have pointed out complications in the use of
    mosses to quantify metal deposition rates. Zechmeister (1998, 156178) found that the uptake
    efficiency for 12 heavy metals in three species of moss was similar, but that uptake efficiency in a
    fourth species was uncorrelated with the other species for about half the metals considered.
    Zechmeister (1998, 156178) also showed that productivity of an individual species can  vary greatly
    among sites. To calculate atmospheric deposition of metals from accumulation in mosses, both the
    metal concentration and the rate of biomass production is needed. Further complication was shown
    in the study of Shakya et al. (2008, 156081). which revealed that accumulation of Cu, Zn and Pb
    decreased chlorophyll content. Sites with greater deposition amounts may therefore have lower rates
    of productivity than cleaner sites.
          Differences in uptake efficiencies among species and productivity among sites  has led to the
    use of a single moss species placed in mesh bags that can be distributed to areas where that species
    of moss does not grow naturally. Studies to standardize this passive deposition monitoring approach
    have been limited. Adamo et al. (2007, 155644) evaluated the effects of washing with water, oven
    drying, and acid washing as preteatments and found little difference in uptake efficiencies, although
    the ratio of the collecting surface area to mass was found to be a key factor in uptake  efficiency.
          Couto et al. (2004, 155739) investigated dry versus bulk deposition of metals using
    transplanted moss bags. This study showed that at some sites dry deposition exceeded bulk
    deposition, a likely outcome of wash-off of dry deposited particles. This study also documented
    intercationic displacement and leaching as a result of acidic precipitation. The authors concluded that
    the accumulated metal concentration represented an unstable equilibrium between inputs and outputs
    of elements that were a function of the local environment and weather during the exposure period.
    They  also concluded that it was not possible to extrapolate calibrations between metal accumulation
    in moss and atmospheric deposition of metals to areas with different weather conditions,
    precipitation pH, and air contaminant concentrations. Zechmeister et al. (2003, 157175) also
    presented results demonstrating the problems with dry deposited particles that can be washed off by
    rain. These studies indicate that moss is not a completely effective collector of total particle
    deposition. Deposition estimates from moss accumulation probably represent values that fall
    between wet deposition and total deposition.
          A European moss biomonitoring network has been in place since 1990  (Harmens et al., 2007,
    155828). Sampling surveys are repeated every five years. The survey conducted in 2005/2006
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    occurred in 32 countries at over 7,000 sites. The network reports metal concentrations associated
    with live moss tissue. Trends analysis of these data showed statistically significant decreases over
    time in moss concentrations for As, Cu, V, and Zn. Trends were not observed for Cr, Fe, or Ni.
    Results for individual countries participating in the survey have also been published. In Hungary,
    major pollution sources were readily detected by moss sampling (Otvos et al., 2003, 156831).
    Somewhat higher metal concentrations in mosses in 1997 than in other European countries were
    attributed to the use of a different moss species in the Hungarian survey (Otvos et al., 2003, 156831).
    Similar sampling in Romania showed regions with contamination that were among the highest in
    Europe. These results were consistent with known air quality problems in Romania (Lucaciu et al.,
    2004, 155947). Because particulate deposition is not well characterized using this method, spatial
    patterns and temporal trends for particulate metal deposition in Europe only provide crude estimates
    of relative deposition patterns.
          The use of moss to assess heavy metal deposition has received much less attention in the U.S.
    than in Europe. A study conducted in the Blue Ridge Mountains, VA, found that metal concentrations
    in moss were related to elevation and canopy  species at some sites (Schilling and Lehman, 2002,
    113075). However, metal concentrations in moss were not related to concentrations in the O horizon
    of the soil. Other measurement methods for trace metal deposition were not available to compare
    with moss concentrations.
          Epiphytic lichens have also been used to evaluate heavy metal  accumulation. Helena et al.
    (2004, 155833) found substantially increased concentrations of metals in lichens transplanted from a
    relatively clean region to an area in proximity to a metal smelter. The presence of specific species of
    bryophyte or lichen can serve as an effective bioindicator of metal contamination (Cuny et al., 2004,
    155742). In some studies, tree bark has been used as a biomonitor for atmospheric deposition of
    heavy metals (Baptista et al., 2008, 155673: Pacheco and Freitas, 2004, 156011: Rusu et al., 2006,
    156062).
          Biomonitoring using mosses, lichens, or other types of vegetation has been established  as a
    means of identifying spatial patterns in atmospheric deposition of heavy metals in relation to power
    plants, industry, and other point and regional emissions sources. More recently, a number of studies
    (Lopez et al., 2002,  155943: 2003, 155944: 2003, 155945) have used cattle that have been reared
    predominantly on local forage as a means of monitoring atmospheric inputs of Cu, Ar, Zn, and Hg.
    For example, Hg emissions from coal fired power plants in Spain had a substantial effect on Hg
    accumulation by calves (Lopez et al., 2003, 155944). Accumulation of Hg by cattle extended to
    -140-200 km downwind from the source.
          Yang and Zhu (2007, 156168) investigated the effectiveness of pine needles as passive air
    samplers for SOCs,  such as PAHs, that are partially or completely particle-associated in the
    atmosphere. PAH distribution patterns are complicated by their properties, which span  a broad range
    of octanol-air partition coefficients. This allows them to be present in both vapor and particle  phases.
    In addition, the air-plant partitioning of PAHs is affected by air temperature and  atmospheric stability
    (Krupa et al., 2008,  198696: Yang  and Chen, 2007, 092847). DeNicola et al. (2005, 155747)
    documented the suitability of a Mediterranean evergreen oak (Quercus ilex) to serve as a passive
    biomonitor for atmospheric contamination with PAH in Italy.
    
    
          Deposition to Canopies
    
          Tree canopies have been shown to increase dry deposition from the atmosphere,  including
    deposition of PM. Dry deposition rates in the canopy are commonly estimated by the difference
    between throughfall deposition and deposition measured by an open collector, although the use of
    this approach to specifically quantify particulate deposition is complicated by gaseous deposition to
    leaf surfaces and, for some elements, leaching and uptake. Avila and Rodrigo (2004, 155664) found
    that trace metal deposition in throughfall in a Spanish oak forest were higher than bulk deposition for
    Cu, Pb, Mn, V, and Ni, but not for  Cd and Zn. This study also found that dry deposition of Cu, Pb,
    Zn, Cd and V occurred, but that canopy uptake of Zn and Cd also occurred. Leaching of Mn and Ni
    from the foliage was observed as well. Leaching  of Ni, Cu, Mn, Rb, and Sr from a red spruce-balsam
    fir canopy by acidic cloud water was also measured in a study by Lawson et al. (2003,  089371).
    These studies suggest that leaching of trace metals from forest canopies varies with tree species and
    the  acidity of precipitation. Throughfall therefore cannot be assumed to represent total deposition  of
    heavy metals without evaluating uptake and leaching at the specific study site. Physical models have
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    provided an alternative to estimating dry deposition to canopies with throughfall measurements.
    Recently, Pry or and Binkowski (2004, 116805) identified an additional complication in that models
    typically hold particle size constant. Nevertheless, there may be significant modification of particle
    size distributions during the deposition process.
          The use of pine and oak canopies as bioindicators of atmospheric trace metal pollution was
    investigated by Aboal et al. (2004, 155642). As an ecosystem pool, metals in leaves were likely to be
    much more important than those in mosses.  The authors concluded, however, that these tree species
    were not effective bioindicators of atmospheric deposition of heavy metals. Metal concentrations in
    leaves were found to be one to three orders of magnitude lower than in mosses collected in this
    study.
          The effectiveness of tree canopies in capturing particulates was investigated as a method for
    improving air quality by Freer-Smith et al. (2004, 156451). This study showed that with
    consideration of planting design, location of pollution source, and tree species, planting of trees can
    be effective at reducing particulate air  pollution. However, this approach does not address the
    possible effects of the captured pollution on trees, soils and surface waters.
          High-elevation forests generally receive larger particulate deposition loadings than equivalent
    low elevation sites. Higher wind speeds at high elevation enhance the rate of aerosol impaction.
    Orographic effects enhance rainfall intensity and composition and increase the duration of occult
    deposition. High-elevation forests are often  dominated by coniferous species with needle-shaped
    leaves that enhance impaction and retention of PM delivered by all three deposition modes.
    
    
          Deposition to Soil
    
          As with mosses, accumulation of heavy metals in surface soils provides a general reflection of
    the spatial distribution of industrial pollution. The distribution of toxic elements in urban soils has
    been an important area of study (Madrid et al., 2002, 155956; Markiewicz et al., 2005, 155963).
    Generally, Cu, Pb, Zn, and Ni have accumulated in urban soils compared with their rural
    counterparts (Yuangen et al., 2006, 156174). In the study of Romic and Romic (2003,  156055).
    relationships were found between urban activities and concentrations of metals in soils in developed
    areas  surrounding Zagreb, Croatia. Goodarzi et al. (2002, 155801) compared deposition estimated by
    moss  bags to concentrations of metals  in A-horizon soils in the vicinity of a large smelter.
    Statistically significant correlations were observed between the moss bag deposition estimates and
    the soil metal concentrations for Cd, Pb, Zn, and in some cases also Cu. These correlations suggested
    that atmospheric deposition of metals caused elevated metal concentrations in the upper mineral
    horizon of these soils. No correlations  were found for Hg or As in this study.
          Studies have also been conducted to assess metal accumulation in peat because of the tendency
    of most metals to be  immobilized through binding with organic matter. Steinnes et al. (2005,
    156095) presented geographical patterns of metal concentrations in surface peat throughout Norway
    that corresponded to  pollution sources, although the peat samples were collected in 1979. Zaccone et
    al. (2007, 179930) found that variations of metal concentrations with depth in a single Swiss peat
    core corresponded with the depositional history that would be expected from the industrial
    revolution, although  Cs137 activity exhibited a distribution in the profile that  was not fully consistent
    with the Chernobyl nuclear reactor accident. A detailed study of Finnish peat showed that
    relationships between depth profiles of metal concentrations and deposition history can match well
    for some metals at some sites, but not well for the same metals at other sites  (Roberts et al., 2003,
    156051). They also found that Zn and  Cd accumulation rates were independent of deposition history
    at each of three study sites.
          Metal deposition to soil is also a significant concern adjacent to roadways. Urban stormwater
    can be rich in heavy metals and other contaminants derived from atmospheric deposition, and can be
    a major source of pollutant inputs to water bodies in urban settings. Urban stormwater runoff can
    also be toxic to aquatic biota, partly  due to trace metal concentrations (Greenstein et al., 2004,
    155808: Sabin et al., 2005, 088300:  Schiff et al., 2002, 156959). These processes are largely a
    function of the impervious nature of much of the ground surface in urban areas (i.e., buildings, roads,
    sidewalks, parking lots, construction sites). Dry-deposited pollutants  can build up, especially in arid
    and semi-arid environments, and then be washed into surface waters with the first precipitation
    event. The concentrations of Cd, Ca, Cu, Pb, and Zn in road runoff were found to be significantly
    higher during winter in Sweden. This seasonal pattern was attributed to the intense wearing of the
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    pavement that occurred during winter due to the use of studded tires in combination with chemical
    effects of deicing salts (Backstrom et al., 2003, 156242).
    
    
    9.4.3.  Direct Effects of PM on Vegetation
    
          Exposure to airborne PM can lead to a range of phytotoxic responses, depending on the
    particular mix of deposited particles. This was well known at the time of the previous PM criteria
    assessment, as summarized below. Most direct phytotoxic effects occur in severely polluted areas
    surrounding industrial point sources, such as limestone quarries and other mining activities, cement
    kilns, and metal smelting facilities (U.S. EPA, 2004, 056905). Experimental application of PM
    constituents to foliage typically elicits little response at the more common ambient concentrations.
    The diverse chemistry and size characteristics of ambient PM and the lack of clear distinction
    between effects attributed to phytotoxic particles and to other air pollutants further confound the
    understanding of the direct effects on foliar surfaces.
          Deposition of PM can cause the accumulation of heavy metals on vegetative surfaces. Low
    solubility limits foliar uptake and direct heavy metal toxicity because trace metals must be brought
    into solution before they can enter into the leaves or bark of vascular plants. In those instances when
    trace metals are absorbed, they are frequently bound in leaf tissue and are lost when the leaf drops
    off (Hughes, 1981. 053595).
          Depending on the size of the particles, the PM deposited on the leaf surface can affect the
    plant's metabolism and photosynthesis by blocking light, obstructing stomatal apertures, increasing
    leaf temperature and altering pigment and mineral content (Naidoo and Chirkoot, 2004, 190449)
    (Section 9.4.3.1.). Fine PM has been shown to enter the leaf through the stomata and penetrate into
    the mesophyll layers where it alters leaf chemistry (Da et al., 2006, 190190). Kuki et al. (2008,
    155346) also showed increased leaf permeability and increased activity of enzymes in response  to
    fine PM lead (Section 9.4.5.).
          Studies of the direct toxic effects  of particles on vegetation have not yet advanced to the stage
    of reproducible exposure experiments. In general, phytotoxic gases are deposited more readily,
    assimilated more rapidly, and lead to greater direct injury of vegetation as compared with most
    common particulate materials. The dose-response functions obtained in early experiments following
    the exposure of plants to phytotoxic gases generally have not been observed following the
    application of particles (U.S. EPA, 2004, 056905).
    
    
    9.4.3.1.   Effects of Coarse-mode Particles
    
          The current state of scientific knowledge regarding the direct effects of coarse PM on plants
    has not changed since publication of the previous PM criteria assessment (U.S. EPA, 2004, 056905).
    The summary provided here is taken from that report. In many rural areas and some urban areas, the
    majority of the mass in the coarse particle mode derives from the elements Si, Al, Ca, and Fe,
    suggesting a crustal origin as fugitive dust from disturbed land, roadways, agriculture tillage, or
    construction activities. Large particles tend to deposit near their source (Grantz et al., 2003, 155805)
    and rapid sedimentation of coarse particles tends to restrict their direct effects  on vegetation largely
    to roadsides and forest edges, which often receive the greatest deposition (U.S. EPA, 2004, 056905)
    
    
          Dust
    
          Dust can cause both physical and chemical effects. Consequences are often mediated via
    impacts on leaf cuticles and waxes. Deposition of inert PM  on above-ground plant organs sufficient
    to coat them with a layer of dust may result in changes in radiation received, a rise in leaf
    temperature, and the blockage of stomata. Crust formation can reduce photosynthesis and the
    formation of carbohydrates needed for normal growth, induce premature leaf-fall, damage leaf
    tissues, inhibit growth of new tissue, and reduce starch storage. Dust may  decrease photosynthesis,
    respiration, and transpiration; and it may result in the condensation and reactivity of gaseous
    pollutants with PM, thereby causing visible injury symptoms and decreased productivity (U.S. EPA,
    2004, 056905).  Leaves with trichomes may be more prone to the accumulation of dust on leaf
    surfaces (Kuki et al., 2008, 155346).
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          The chemical composition of PM is usually the key phytotoxic factor leading to plant injury.
    For example, cement-kiln dust liberates calcium hydroxide on hydration. It can then penetrate the
    epidermis and enter the mesophyll, causing an increase in leaf surface pH. In turn, surface pH can be
    important for surface microbial colonization and wax formation and degradation.
    
    
          Salt
    
          Sea-salt particles can serve as nuclei for the absorption and subsequent reaction of other
    gaseous and particulate air pollutants. Direct effects on vegetation reflect these inputs and salt injury
    caused by the sodium and chloride that constitute the bulk of these particles. The source of most salt
    spray near the coast is aerosolized ocean water. Sea salt can cause damage to plants; however, it is
    not covered in this assessment because it is not of anthropogenic origin. However particulate salt
    may be input to an ecosystem from deicing salt.
          Injury to vegetation from the application of deicing salt is caused by salt spray blown or
    drifting from the highways (Viskari and Karenlampi, 2000, 019101). The most severe injury is often
    observed nearest the highway. Conifers planted near roadway margins in the eastern U.S.  often
    exhibit foliar injury due to toxic amounts of saline aerosols deposited from deicing solutions
    (U.S. EPA, 2004, 056905).
    
    
    9.4.4.  PM and Altered Radiative Flux
    
          The effects of PM on radiative flux and the subsequent effects on vegetation have been
    described in Section 4.2.3.2 of the previous PM assessment (U.S. EPA, 2004, 056905): a brief
    overview is presented below. Atmospheric PM can affect ambient radiation, which can be considered
    in both its direct and diffuse components. Foliar interception by canopy elements occurs for both up-
    and down-welling radiation. Therefore, the effect of atmospheric PM on atmospheric turbidity
    influences canopy processes both by radiation attenuation and by changing the efficiency  of
    radiation interception in the canopy through conversion of direct to diffuse radiation (Hoyt, 1978,
    046638). Diffuse radiation is more uniformly distributed throughout the canopy and increases
    canopy photosynthetic productivity by distributing radiation to lower leaves. The enrichment in
    photosynthetically active radiation (PAR) present in diffuse radiation may offset a portion of the
    effect of an increased atmospheric albedo due to atmospheric particles. Mercado et al. (2009,
    190444) estimated the effects of variations in diffuse light on the terrestrial carbon sink during the
    last century using a global model.  The results indicated that the terrestrial carbon sink increased by
    approximately 25% during the "global dimming'" period (1950-1980), likely driven by increased
    diffuse light despite decreased PAR. However, under a future scenario in which SO42~ and BC
    aerosols decline, the diffuse-radiation and the associated terrestrial C sink also decline (Mercado et
    al., 2009, 190444).
          The effects of regional haze on the yield of crops because of reduction in solar radiation were
    examined by Chameides et al. (1999, 011184) in China, where  regional haze is especially severe.
    Based on model results, it was estimated that approximately 70% of crops were being depressed by
    at least 5-30% by regional scale air pollution and its associated haze (Chameides et al., 1999,
    011184: U.S. EPA, 2004, 056905).
    
    
    9.4.5.  Effects  of Trace Metals on Ecosystems
    
          Trace metals may enter the ecosystems as both fine and coarse particles. All but 10  of the 90
    elements that comprise the inorganic fraction of the soil occur at concentrations of <0.1%
    (1,000 ug/g) and are termed "trace" elements or trace metals. Trace metals with a density  greater
    than 6 g/cm3, referred to as "heavy metals" (e.g., Cd, Cu, Pb, Cr, Hg, Ni, Zn), are of particular
    interest because of their potential toxicity to plants and animals. Although some trace metals are
    essential for vegetative growth or animal health, they are all toxic  in large quantities. Most trace
    elements exist in the atmosphere in particulate form as metal oxides (Ormrod,  1984, 046892).
    Aerosols containing trace elements derive predominantly from industrial activities. Generally, only
    the heavy metals Cd, Cr, Ni, and Hg are released from stacks in the vapor phase (McGowan et al.,
    1993, 046731). Atmospherically deposited PM can interact with a variety of biogeochemical
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    processes. The potential pathways of accumulation of trace metals in terrestrial ecosystems, as well
    as the possible consequences of trace metal deposition on ecosystem functions, are summarized in
    Figure 9-85 (U.S. EPA, 2004, 056905). A number of mass balance approaches (Macleod et al., 2005,
    155954; Toose and Mackay, 2004, 156123). and metal speciation and transport models (Bhavsar et
    al., 2004, 155689: Bhavsar et al., 2004, 155690: Gandhi et al., 2007, 155781) have been developed
    in recent years.
          Atmospheric Pb is a component of PM in some regions. The effects of Pb on ecosystems were
    discussed in the 2006 Pb AQCD (U.S. EPA, 2006, 090110). which concluded that, due to the
    deposition of Pb  from past human practices (e.g., leaded gasoline, ore smelting) and the long
    residence time of Pb in many aquatic and terrestrial ecosystems, a legacy of environmental Pb
    burden exists, over which is superimposed much lower contemporary atmospheric Pb loadings. The
    potential for ecological effects of the combined legacy and contemporary Pb burden to occur is a
    function of the bioavailability or bioaccessibility of the Pb. This, in turn, is highly dependent upon
    numerous site factors (e.g., soil OC content, pH, water hardness). Although the more localized
    ecosystem impacts observed around smelters are often striking, effects generally cannot be attributed
    solely to Pb, because of the presence of many other stressors (e.g., other heavy metals, oxides of
    sulfur and nitrogen) that can also act singly or in concert with Pb to  cause readily observable
    environmental effects (U.S.  EPA, 2004, 056905: U.S. EPA, 2008, 157074).
          Effects of fine particle trace elements were described by the U.S.  EPA (2004, 056905). and
    some additional more recent research has also been conducted, especially  on the topic of vegetative
    uptake of trace elements from the soil. The state of scientific understanding as presented by the U.S.
    EPA (2004, 056905) as well as a discussion of more recent research findings are presented below.
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       1. Wet/Dry Deposition
                                   Atmosphere
                                                                                 9. Retranslocation
       3. Litterfall, Resuspension,
          Deposition, Leaching,
          Stem Flow
    Plant Surface
    Phyllosphere
                                                  2. Foliar Uptake
                                          Above-
                                          Ground
                                         Storage,
                                        Metabolism
                                                                              4. Translocation
        Biologically
        Unavailable
           IX.
      Soil Organic
           X.
        Primary
        Minerals
     Biologically / /
     Available / /
        IV.
    Upper Soil
                   5. Mass Flow,
                     Diffusion
                                                     .10. Root
                                                         Turnover
                                          7. Leaching
       VII.
    Lower Soil
    V.
    Rhizosphere/
    Rhizoplane
    
    ^-
    6. Root"
    Uptake
                                                        VI.
                                                   Root Storage,
                                                    Metabolism
                   5. Mass Flow,
                     Diffusion
                                        X 7. Leaching
                                       VIII.
                                   Groundwater
                                                                                Source: U.S. EPA (2004, 0569051
    Figure 9-85.    Relationship of plant nutrients and trace metals with vegetation.  Compartments
                   (roman numerals) represent potential storage sites; whereas arrows (Arabic
                   numerals) represent potential transfer routes.
    9.4.5.1.   Effects on Soil Chemistry
    
          Trace metals are naturally found in small amounts in soils, ground water, and vegetation.
    Many are essential micronutrients required for growth by plants and animals. Naturally occurring
    mineralization can produce metal concentrations in soils and vegetation that are high compared to
    atmospheric sources. Many metals are bound by  chemical processes in the soil, reducing their
    availability to biota. However, epiphytic or parasitic root colonizing microorganisms can solubilize
    and transport metals for root uptake (Lingua et al., 2008, 155935). It can be difficult to assess the
    extent to which observed heavy metal concentrations in soil are of anthropogenic origin.  This is
    because soil parent material, pedogenesis, and anthropogenic inputs all influence the amounts and
    distribution of trace elements in soil. Trace element concentrations in some natural soils that are
    remote from air pollution can be higher than soils derived from other parent materials that receive
    anthropogenic inputs (Burt et al., 2003, 155709). The general effects of metals from atmospheric
    deposition are presented in the following discussion.
          There is not a standard method available for quantifying the bioavailability of heavy metals in
    soil. A variety of models, isotopic studies, and sequential extraction methods have been used (Collins
    et al., 2003, 155737: Feng et al., 2005, 155774; Shan et al., 2003, 156972). Total metal concentration
    in soil does not give a good indication of potential biological effects because soils vary in their
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    ability to bind metals in forms that are not bioavailable. There are various methods available for
    assessing bioavailability of metals, but soils are heterogeneous and there is no ideal method for
    evaluating what conditions the soil biota experience. Almas et al. (2004, 155654) argued that the
    actual measurement of biological effects is the best criterion for determining bioavailability.  In
    particular, the replacement of metal-sensitive microorganisms by metal-tolerant organisms within
    each functional group may be one of the most sensitive indicators of metal exposure. An increase in
    microbial trace metal tolerance per se would not be problematic if it was not for the fact that this
    increase in tolerance is generally accompanied by a decrease in microbial diversity (Almas et al.,
    2004, 155654; Lakzian et al., 2002, 156671).
          Heavy metals deposited from the atmosphere to forests accumulate either in the organic forest
    floor or in the upper mineral soil layers and metal concentration tends to decrease with soil depth.
    The accumulation of heavy metals in soil is influenced by a variety of soil characteristics, including
    pH, Fe and Al oxide content, amount of clay and organic  material, and cation exchange capacity
    (CEC) (Hernandez et al., 2003, 155841). Thus, the pattern of distribution of heavy metals in soils
    depends on both the soil characteristics and the metal characteristics.
          Burt et al. (2003, 155709) investigated the concentrations and chemical forms of trace metals
    in smelter-contaminated soils collected in the Anaconda and Deer Lodge Valley area of Montana,
    one of the major mining districts of the world for over a century (1864-1983). The relative
    distributions of trace metals within the more soluble soil extraction forms were similar to their
    respective total concentrations. This suggested a relationship between the concentrations of total
    trace elements and concentrations of soluble mobile fractions. Sequential extractions do not provide
    direct characterization of trace metal speciation, but rather an indication of chemical reactivity (Burt
    et al., 2003, 155709; Ramos et al., 1994, 046736).  Soluble and exchangeable forms are considered
    readily mobile and bioavailable. Those bound to clay minerals or organic matter are considered
    generally unavailable.
          There is concern that Pb contamination of forest soil could move into groundwater. This would
    be important in view of the large quantity of Pb deposited from the atmosphere in the 1960s  and
    1970s in response to combustion of leaded gasoline. This issue was investigated by Watmough et al.
    (2004, 077809) who applied a stable isotope (207Pb) to the forest floors of white pine (Pinus strobus)
    and sugar maple (Acer saccharum) stands. Added Pb was rapidly lost from the forest floor, likely
    due to high litter turnover in these forest types. However, Pb concentrations in the upper 30 cm of
    mineral soil were strongly correlated with soil OM, suggesting that Pb does not readily move down
    the soil profile to the ground water, but rather is associated with the organic content of the upper  soil
    layers (Watmough  et al., 2004, 077809).
          The upper soil layers are typically an active site of litter decomposition and plant root  uptake,
    both processes may be affected by metal components of PM. Surface litter decomposition is  reduced
    in soils having high metal concentrations. This is likely due to the sensitivity to metals  of microbial
    decomposers  and reduced palatability of plant litter having high metal concentration (Johnson  and
    Hale, 2008, 155881). Root decomposition is a key component of nutrient cycling. Johnson and Hale
    (2008, 155881) measured in situ fine root decomposition at Sudbury, Ontario and Rouyn-Noranda,
    Quebec. Elevated soil metal concentrations (Cu, Ni, Pb, Zn) did not necessarily reduce fine root
    decomposition. Only at sites having high concentrations of metals did decomposing roots show
    increased metal concentrations over time.
    
    
    9.4.5.2.   Effects on Soil Microbes and Plant Uptake  via Soil
    
          Upon entering the soil environment, PM pollutants can alter ecological processes of energy
    flow and nutrient cycling, inhibit nutrient uptake, change ecosystem structure, and affect ecosystem
    biodiversity. Many of the most important effects occur in the soil. The soil environment is one of the
    most dynamic sites of biological interaction in nature. It is inhabited by microbial communities of
    bacteria, fungi, and actinomycetes. These organisms are essential participants in the nutrient cycles
    that make elements available for plant uptake. Changes in the soil environment that influence the
    role of the bacteria and fungi in nutrient cycling determine plant and ultimately ecosystem response.
          Many of the  major indirect plant responses to PM deposition are chiefly soil-mediated and
    depend on the chemical composition of the individual components of deposited PM. Effects  may
    result in changes in biota and in soil conditions that affect ecological processes, such as nutrient
    cycling and uptake by plants.
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          The soil environment is rich in biota. Bacteria and fungi are usually most abundant in the
    rhizosphere, the soil around plant roots that all mineral nutrients must pass through. Bacteria and
    fungi benefit from the nutrients that are present in root exudates and make mineral nutrients
    available for plant uptake. The soil-mediated ecosystem impacts of PM are largely determined by
    effects on the growth of bacteria and mycorrhizal fungi that are involved in nutrient cycling and
    plant nutrient uptake.
    
    
          Soil Nutrient Cycling
    
          Accumulation of heavy metals in litter can interfere with nutrient cycling. Microorganisms are
    responsible for decomposition of organic matter, which contributes to soil fertility. Toxic effects on
    the microflora can be caused by Zn, Cd, and Cu. The U.S. EPA (2004, 056905) judged that addition
    of only a few mg of Zn per kg of soil can inhibit sensitive microbial processes. Enzymes involved in
    the cycling of N, P, and S (especially arylsulfatase and phosphatase) seem to be most affected
    (Kandeler et al., 1996, 094392).
          Soil organic matter cycling is known to be sensitive to disturbance due to heavy metal
    pollution. This can cause increased litter accumulation at sites close to metal emissions point
    sources. The relative importance of the various processes that might be responsible for this
    observation  is poorly known. Boucher et al. (2005, 155699) conducted CO2 evolution studies in
    microcosms having metal-rich and metal-poor plant materials. Their results suggested that there was
    a pool of less readily decomposable C that appeared to be preferentially preserved in the presence of
    high metal (Zn, Pb, Cd) concentrations in  the leaves of the metallophyte Arabidopsis halleri. An
    additional possibility is that increased lignification of the cell walls increased the amount of
    insoluble C (Mayo et al., 1992, 155974).
          Yuangen et al. (2006, 156174) found that urban soil basal respiration rates were positively
    correlated with soil acetic acid-extractable Cd, Cu, Ni, and Zn. The soil microbial biomass was
    negatively correlated with the concentrations of Pb fractions, but not with other metals. Overall
    microbial biomass was lower for urban soils as compared with rural soils (Yuangen et al., 2006,
    156174).
    
    
          Metal Toxicity to Microbial Communities
    
          It is believed that increased accumulation of litter in metal-contaminated areas is due to the
    effects of metal toxicity on microorganisms. Smith (1991, 042566) reported the effects of Cd, Cu,
    Ni, and Zn on the symbiotic activity of fungi, bacteria, and actinomycetes. In particular, the
    formation of mycorrhizae has been shown to be reduced when Zn, Cu, Ni, and Cd were added to the
    soil.
          Most studies of the effects of heavy metals on soils have been conducted under laboratory
    conditions. However, Oliveira and Pampulha (2006, 156827) performed a field study to evaluate
    long-term changes in soil microbiological characteristics  in response to heavy metal contamination.
    Dehydrogenase activity, soil ATP content, and enumeration of major soil  microbial groups illustrated
    the effects of contamination. There was a marked decrease in total numbers of the different microbial
    groups. In particular, asymbiotic nitrogen-fixers and heterotrophic bacteria were found to be
    sensitive. Dehydrogenase activity was confirmed to be a good assay for determining the effect of
    heavy metals on physiologically active soil microbial biomass.
          The toxic effects of heavy metals on soil microorganisms are well known. However, less is
    known about the relative sensitivity of different types  of soil microorganisms (Rajapaksha et al.,
    2004, 156035). Vaisvalavicius et al. (2006, 157080) assessed the toxicity of high concentrations of
    Pb (839 mg/kg), Zn (844 mg/kg), and Cu (773 mg/kg) in the upper 0-0.1  m soil layer. Microbial
    abundance of all  groups was reduced and  enzymatic activity  was lower than for uncontaminated soil.
    In particular, actinomycetes, oligonitrophobic and mineral N assimilating bacteria were most
    affected.
          Effects of heavy metals in soil on microbes depends on soil pH, organic content, and the type
    of heavy metal exposure (Kucharski and Wyszkowska, 2004, 156662). Some studies have shown
    that heavy metals inhibit microbial  activity in soil (Smejkalova et al., 2003, 156987; Vasundhara et
    al., 2004, 156133). However, Wyszkowska et al. (2007, 179948) showed that heavy metals can either
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    inhibit or stimulate the growth of soil microbes. Populations of Azotobacter spp. decreased, but
    populations of oligotrophic and copiotrophic bacteria, actinomyces, and fungi increased in response
    to heavy metal exposure. Acute metal stress causes a decrease in microbial biomass as
    metal-sensitive microbes are inhibited (Joynt et al., 2006, 155887).
          Studies of the impacts  of metal stress on the microbial community composition in soil have
    generally been based on microbial culturing techniques that can select only a subset of the natural
    soil population of microbes. More recent culture-independent studies have been conducted using
    phospholipids or nucleic acid biomarkers to reveal information regarding changes in microbial
    community structure (Joynt et al., 2006, 155887). Using this approach, Joynt et al.(2006,  155887)
    demonstrated that soils contaminated with both metals (Pb, Cr) and organic solvent compounds over
    a period of several decades had undergone  changes in community  composition, but still contained a
    phytogenetically diverse group of bacteria.  This may reflect adaptation to the potentially toxic
    conditions through such processes as natural selection, gene exchange, and immigration.
    Comparison between a severely contaminated soil with a similar soil that had much lower amounts
    of contamination showed considerably lower microbial diversity in the contaminated soil,
    particularly for asymbiotic nitrogen fixers and heterotrophic bacteria (Oliveira and Pampulha,  2006,
    156827).
          As pollution increases, it is expected that the more sensitive species will be lost and the more
    tolerant species remain. This gives rise to the concept of pollution-induced community tolerance
    (PICT), which has been demonstrated for populations of bacteria and fungi (Davis et al., 2004,
    155744). These researchers assessed the effects of long-term Zn exposure on the metabolic diversity
    and tolerance to Zn of a soil microbial community across a gradient of Zn pollution. PICT was found
    to correlate better with total soil Zn than with the concentration of Zn in soil pore water.
    
    
          Soil Microbe Interactions with Plant Uptake of Metals
    
          Atmospherically-deposited metals accumulate in upper soil horizons where fine roots are most
    developed. The availability for plant uptake of metals in soil depends on metal speciation and soil
    pH. In addition, metal binding to dissolved organic matter (DOM) reduces bioavailability (Sauve,
    2001, 156948). Because organic matter typically decreases with soil depth, the affinity of metals for
    organic matter can influence  metal bioavailability at different soil depths. Fine roots (<2 mm
    diameter) provide the major site of uptake and transport to the above-ground  plant and generally
    contain a large proportion of the total metals found in plants (Gordon and Jackson, 2000, 155802).
          Fine roots are often colonized by mycorrhiza and interact with other soil microbes.  Recent
    published evidence supports that mycorrizha and bacteria influence plant uptake and tolerance  of
    metals. Mycorrhiza are fungi that colonize  plant roots to form a symbiosis. Mycorrhiza take up
    nutrients from the soil and transfer them to  the plant in exchange for carbon from the plant. Like
    plants, some species and strains of mycorrhiza are more tolerant of metals in  the soil (Ray et al.,
    2005, 190473). so that unpolluted and polluted sites may host different species and strains of
    mycorrhiza (Vogel-Mikus et al., 2005, 190501).
          Mycorrhiza have been observed to cause a range of effects on plants. In some cases, plants
    colonized with mycorrhiza showed improved nutrient uptake and decreased metal uptake (Berthelsen
    et al., 1995, 078058; Nogueira et al., 2004,  190460; Vogel-Mikus et al., 2006, 190502). Mycorrhiza
    have been shown to accumulate metals and act as a sink (Berthelsen et al., 1995, 078058; Carvalho
    et al., 2006, 155715) often preventing the metals in the roots from allocation to shoots (Kaldorf et
    al.,  1999, 190399; Scares  and Siqueira, 2008, 190482; Zhang et al., 2005, 192083). For example,
    estuarine salt marshes are often located close to urban and industrial areas and receive elevated
    amounts of trace metal contaminants from point and non-point (including atmospheric deposition)
    sources. Vegetation is important in the retention and accumulation of heavy metals in salt marshes.
    Carvalho et al. (2006, 155715) conducted experiments on the effects of arbuscular mycorrhizal fungi
    (AMF) on the uptake of Cd and Cu by Aster tripolium, a common plant species in polluted salt
    marshes and a host of AMF. Carvalho et al. (2006, 155715) found  that AMF colonization increased
    metal accumulation in the root system of Aster tripolium without enhancing translocation to the
    shoot. By trapping toxic metals in the roots, this plant species may reduce the extent of vegetative
    stress caused by metal exposure and act as  an effective sink for these metals.  In a review paper
    Christie et al. (2004,  190174) concluded that mycorrhiza may directly improve plant tolerance  to
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    metals by binding and immobilizing metals and indirectly improve plant tolerance by improving
    uptake of nutrients that increase plant growth.
          There is recent evidence that bacteria and mycorrhiza act together to improve plant tolerance
    to metals. Like mycorrhiza some bacteria are more tolerant to metals than others (Vivas et al., 2003,
    190499). Combined inoculation of Trifolium sp. by the arbuscular mycorrhiza, Glomus mosseae, and
    the bacterium, Brevivacillus sp., conferred tolerance to Cd by increasing nutrient status and rooting
    development and by decreasing Cd uptake by the plant (Vivas et al., 2003, 190499). A similar result
    was observed for Zn uptake (Vivas et al., 2006, 190500).
          In some cases, mycorrhizae will not prevent metal uptake (Weissenhorn et al., 1995, 073826).
    In fact, mycorrhiza may facilitate the accumulation of metals in plants and enhance the translocation
    of metals from the root to the shoot (Citterio et al., 2005, 190176; Vogel-Mikus et al., 2005,  190501;
    Zimmer et al., 2009, 192085). There is evidence of variable responses depending on the combination
    of mycorrhiza and bacteria species. Zimmer et al. (2009, 192085) recently showed that the willow
    tree (Salix sp.) colonized with the ectomycorrhizal fungus, Hebeloma crustuliniforme, and the
    bacteria, Microcuccus Inters, increased total Cd and Zn accumulation due to enhanced mycorrhizal
    formation. In these cases where soil microbes cause increased metal accumulation,  there is a
    potential to use the system for phytoremediation.
          Plants also vary in the extent to which they take up heavy metals from the soil. Variability has
    been shown to occur in response to different plant species and different metals. For example, Szabo
    and Fodor (2006,  156109) exposed winter wheat (Triticum aestivum), maize (Zea mays) and
    sunflower (Helianthus annuus) to a variety of micro-pollutants. Cadmium accumulation was
    significant in both vegetative and reproductive plant parts. Vegetative winter wheat accumulated
    substantial amounts of Hg, but the other species did not. Lead, Cu, and Zn showed only moderate
    enrichment in crops (Szabo  and Fodor, 2006, 156109).
          There is some evidence to support that shallow-rooted plant species are most likely to take up
    metals from the soil (Martin  and Coughtrey, 1981, 047727). However, there is little evidence
    confirming this observation. It may be more likely that shallow roots of species are likely to take up
    metals because the metal often accumulates in shallow soil layers. Even though atmospheric PM will
    usually deposit on soils before being taken up by plants, it could also be deposited to aquatic systems
    with subsequent transfer to terrestrial plants. Contamination of stream sediments by heavy metals
    can impact adjacent terrestrial ecosystems when high flows cause resuspension and subsequent
    streamside deposition of sediment  particles. For example, Ozdilek et al. (2007, 156010) showed that
    metal concentrations in vegetation along the Blackstone River in Massachusetts and Rhode Island
    were generally inversely related to the distance from the riverbank, with higher metal concentrations
    in plant tissues located near the river. The ability of plants to take up metals from soil is an important
    part of metal cycling in the environment. This uptake process allows the metals to enter the food
    web, where they might exert mutagenic, carcinogenic, and teratogenic effects  (Hunaiti et al., 2007,
    156579).
    
    
    9.4.5.3.   Plant Response to Metals
    
          Some metals,  including Cu,  Co, Ni,  and Zn, are essential  micronutrients needed for plant
    growth. Others, including Hg, Cd,  and Pb are not essential for plants. Though all heavy metals can
    be directly toxic at sufficiently high concentrations, only Cu, Ni, and Zn have been documented as
    being frequently toxic to plants (U.S. EPA, 2004, 056905). while toxicity due  to Cd, Co,  and Pb has
    been observed less frequently (Smith, 1990,  046896). Toxic doses depend on the type of ion, ion
    concentration, plant species and the stage of plant growth (Memon and Schroder, 2009, 190442).
    Toxicity response is also dependent on the nutritional status of the plant and the development of
    mycorrhizae (Strandberg et al., 2006,  156105). Plants respond to high concentrations of metals  in
    soil through a variety of mechanisms and there are substantial differences among plant species in
    their response to heavy metal exposure. Mechanisms of metal tolerance included exclusion or
    excretion rates, genetics (Patra et al., 2004, 081976; Yang et al., 2005, 192104). mycorrhizal
    interactions (Gohre  and Paszkowski, 2006, 190355). storage capability and accumulation (Clemens,
    2006, 190179). and various cellular detoxification mechanisms  (Gratao et al.,  2005, 190364; Hall,
    2002, 190365).
          One of the most important mechanisms that increases plant tolerance to metals is chelation
    with phytochelatins, such as metallothioneins and peptide ligands that are synthesized within the
    plant from glutathione (Memon and Schroder, 2009, 190442). Phytochelatins are intracellular
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    metal-binding peptides that act as specific indicators of metal stress. Because they are produced by
    plants as a response to sublethal concentrations of heavy metals, they can indicate that heavy metals
    play a role in forest decline (Gawel et al., 1996, 012278). Phytochelatin concentrations have
    previously been measured in coniferous trees in the northeastern U.S. The U.S. EPA (2004, 056905)
    and Grantz et al. (2003, 155805) summarized studies indicating that both the number of dead red
    spruce trees and phytochelatin concentrations increased sharply with elevation in the northeastern
    U.S. Red spruce stands showing varying degrees of decline indicated a systematic and significant
    increase in phytochelatin concentrations associated with the extent of tree injury. These data suggest
    that metal stress might contribute to tree injury and forest decline in the northeastern U.S. The extent
    to which low to moderate amounts of heavy metal deposition, which might occur at locations that are
    not in close proximity to a large point source, contribute to adverse impacts on forest vegetation is
    not known. Although the phytochelatin data suggest a linkage, more direct experimental data would
    be needed to confirm such a finding.
          In general, plant growth is negatively correlated with trace metal and heavy metal
    concentration in soils and plant tissue (Audet and Charest, 2007, 190169). Trace metals, particularly
    heavy metals, can influence forest growth. Growth suppression of foliar microflora has been shown
    to result from Fe, Al, and Zn. These three metals can also inhibit fungal spore formation, as can Cd,
    Cr, Mg, and Ni (see Smith, 1990, 046896). Metals cause stress and decreased photosynthesis
    (Kucera et al., 2008, 190408) and disrupt numerous enzymes and metabolic pathways (Strydom et
    al., 2006, 190486). Excessive concentrations of metals result in phytotoxicity through: (i) changes in
    the permeability of the cell membrane; (ii) reactions of sulfydryl (-SH) groups with  cations; (iii)
    affinity for reacting with phosphate groups and active groups of ADP or ATP; and (iv) replacement
    of essential ions (Patra et al., 2004,  081976).
          In addition to disrupting photosynthesis and other metabolic pathways, metals have been
    shown to alter frost hardiness and impair nutrition. A recent review by Taulavuori (2005, 190489)
    suggests that metal- induced stress reduces frost hardiness of plants, a particular concern at high
    elevation sites. Kim et al. (2003, 155899) found decreased concentration of K in needles and Ca in
    stems ofPinus sylvestris seedlings exposed to Cd addition. This response suggests a disturbance of
    nutrition in response to Cd.  Pollutant-caused needle loss can reduce the interception of pollutants
    from the atmosphere, and therefore reduce their concentrations in stemflow.  This may be responsible
    for the observation that species diversity of lichens is sometimes higher on trees affected by die-back
    (Hauck, 2003, 155830).
          Da Silva et al. (2006, 190190) have shown that PM had anatomical and physiological effects
    on plants growing near an iron pelletization factory in Brazil. The  effects of PM occurred due to
    foliar uptake. Structural characteristics such as peltate trichomes may have formed a barrier
    lessening the penetration of metallic iron into the  mesophyll in some species. Iron was shown to
    penetrate the trichomes,  epidermic cells (adaxial and abaxial surfaces), stomata, xylem cells,
    collenchyma, endodermis and mesophyll tissues. Once entering the stomata, the PM penetrates
    within the mesophyll, it may modify the chemical balance of the mesophyll (Da et al., 2006,
    190190).
          A greenhouse study evaluated the combined effects of iron dust on restinga vegetation (coastal
    vegetation of Brazil) that commonly grows near iron ore industries. Kuki et al. (2008, 155346) found
    that iron dust had differing effects on gas exchange, chlorophyll content, iron content and antioxidant
    enzyme activity on two plant species common to the restinga. Schinus terebinthifolius (an invasive
    exotic in the U.S.) was not affected by the iron dust. However, Sophora tomentosa showed increased
    iron  content and membrane permeability to the leaves, increasing activity of antioxidant enzymes.
    These results showed that the plants used different strategies to cope with PM pollution. S.
    terebinthifolius avoided stress, while S. tomentosa used antioxidant enzyme  systems to partially
    neutralize oxidative stress.
          Plant foliage can accumulate  elemental Hg  over time in response to air exposure and
    concentrations in soil (Ericksen et al., 2003, 155769; Frescholtz et al., 2003, 190352). Amesocosm
    experiment was conducted by Ericksen et al. (2003, 155769) where aspen trees were grown in
    gas-exchange chambers in Hg-enriched soil (12.3 ±1.3 ug/g) and the Hg content in the foliage was
    analyzed. Foliar Hg increased with  leafage for 2-3 mo and then stabilized at leaf concentrations near
    150 ng/g. About 80% of the Hg found in above-ground biomass was present in the leaves. The
    concentration of Hg in trees grown  in the same mesocosms  in containers of low Hg  soil
    (0.03 ±0.01 ug/g) exhibited foliar Hg concentrations that were similar to those of trees grown in
    Hg-enriched soil. Almost all of the foliar Hg originated from the atmosphere. Clearly, plant foliage
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    can be a major sink for airborne Hg, which can subsequently enter the soil after litterfall (Ericksen et
    al., 2003, 155769). However, this study did not determine the extent to which atmospheric Hg was
    dry-deposited on the foliage, as opposed to gaseous uptake through the stomata. Foliar/air Hg
    exchange has been shown to be dynamic and bi-directional (Millhollen et al., 2006, 190447). These
    investigators compared foliar Hg accumulation over time in three tree species with fluxes measured
    using a plant gas-exchange system subsequent to soil amendment with HgCl2. Root tissue Hg
    concentrations were strongly correlated with soil Hg concentrations, suggesting that below-ground
    accumulation of Hg by roots may be an important process in the biogeochemical cycling of Hg in
    soil systems. Nevertheless, measured foliar Hg fluxes indicated that deposition of atmospheric Hg
    constituted the dominant flux of Hg to  the leaf surface (Millhollen et al., 2006, 190447). Grigal
    (2003, 155811) also found that Hg in vegetation is derived almost exclusively from the atmosphere.
    Mercury uptake from soil is limited, partly because roots adsorb Hg but transport it to foliage very
    poorly (Grigal,  2002, 156498). Grigal (2003, 155811) provided a thorough review of the
    sequestration of Hg in forest and peatland ecosystems. A fundamental aspect of Hg cycling is its
    strong relationship to organic matter. For that reason, peatlands sequester much larger quantities of
    Hg than would  be expected  on the basis of their land area. Thus, if global climate change affects C
    storage, it may  indirectly affect Hg  storage because of the strong relationship between Hg and
    organic matter (Grigal, 2003, 155811).
          Arbuscular mycorrhizal (AM) fungi can play important roles in mitigating toxicity of heavy
    metals in plants. For example, AM symbiosis is known to be involved in plant adaptation to
    As-contaminated soils. Higher plants that are adapted to As contaminated soils are generally
    associated with mycorrhizal fungi (Gonzalez-Chavez et al., 2002, 155800). It has also been shown
    that AM symbioses can influence plant coexistence and community diversity (O'Connor, 2002).
    Some plants associated with AM fungi can successfully colonize sites that are heavily contaminated
    by heavy metals (Pennisi, 2004, 156018).
          Dong et al. (2008, 192106) cultivated white clover (Trifolium repens) and ryegrass (Lolium
    perenne) in As-contaminated soil (water extractable As 82.7 mg/kg). The growth and P nutrition of
    both species largely depended on AM symbiosis. The AM-inoculated plants showed selective uptake
    and transfer of P over As.
          PM pollution has the potential to alter species composition over long time scales. Kuki et al.
    (2009, 190411) showed that early establishment stages ofSophora tomentosa species were
    negatively affected by the combination of iron ore and acidifying particles. The deleterious effects of
    the PM included deficient germination and toxic concentrations  in roots. In contrast, S.
    terebinthifolius was not affected by the PM revealing species resistance to  the pollution. The
    difference among species response suggests that over a long time period the imbalance will likely
    change the species composition (Kuki  et al., 2009, 190411).
          The process  of removing toxins from soil or water using photoautotrophs is referred to as
    phytoremediation.  Some plant species have good ability to extract heavy metals from soil, thereby
    offering potential for phytoremediation (Clemens, 2006,  190179; Hooda, 2007, 190382;
    Padmavathiamma  and Li, 2007, 190465). For example, several species of willow (Salix spp.)
    accumulate high concentrations of Zn and Cd in aboveground biomass (Lunackova et al., 2003,
    155948; Meers  et al., 2007,  155977; Rosselli et al., 2003, 156058). A first  estimation of the order of
    magnitude of potential metal removal by willow was 2 to 27  kg/ha/yr of Zn and 0.25 to 0.65 kg/ha/yr
    for Cd (Meers et al., 2007, 155977). Build-up of high concentrations of trace metals in soil is
    difficult to remediate because of the long residence times of metals in the environment. Plants that
    survive on heavy metal-contaminated soils have been studied to elucidate the mechanisms that allow
    them to tolerate such conditions and interactions between soil contamination and vegetation
    composition (Becker and Brandel,  2007, 156260; Hall, 2002, 190365). There are numerous other
    plants that have been investigated for application to phytoremediation. Plants that hyperaccumulate
    metals have special potential for remediation of metal-contaminated sites.  About 400 species have
    been reported. Brassicaceae has the largest numbers of taxa, with 11 genera and 87 species known to
    hyperaccumulate one or more metal contaminants (Prasad  and DeOliveira, 2003, 156885).
          Plant uptake is often the first  step for a metal to enter higher levels of the food web.
    Consumers of vegetation may often receive heavy loading of metals from their diets. Metals may
    also bioaccumulate in  some species and tissue  concentrations are magnified at the higher trophic
    levels, so-called biomagnifications  (see Section 9.4.5.7. on Biomagnification).
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    9.4.5.4.   Effects on Aquatic Ecosystems
    
          The atmospheric deposition of PM into the ocean has important implications for primary
    productivity and carbon sequestration. In part, metals in PM deposition may limit phytoplankton
    growth in parts of the ocean (Crawford et al, 2003, 156370). In particular, Fe and Zn can influence
    the productivity of algae that are involved in CaCO3 production. The production of both particulate
    organic C and CaCO3 drive the ocean's biological carbon pump (Shulz et al., 2004, 156087). Thus,
    in oceanic areas of trace metal limitation, changes in trace metal atmospheric deposition can affect
    biogenic calcification, with potential consequences for CO2 partitioning between the ocean and
    atmosphere.
          A study by Sheesley et al. (2004, 156084) illustrated the value of bioassay procedures to
    provide an initial screening of ambient PM toxicity. They used two species of green algae and two
    extraction methods to compare the toxicities of atmospheric PM collected at two urban/industrial
    sites and one rural site near the southern shore of Lake Michigan. Toxi cities varied by site, by
    extraction solvent,  and by bioassay. Results suggested that toxicity was not related to the total mass
    of PM in the extract, but to the chemical components of the PM. It is noteworthy that the
    concentrations of contaminants in PM in this type of short-term and acute toxicity testing are much
    higher than would be found in the natural environment. Thus, the purpose of this type of testing is to
    provide an initial screening-level comparison of relative toxi cities of atmospheric PM from different
    source areas.  It does not provide the data that would be needed to assess risk (Sheesley et al., 2004,
    156084).
    
    
    9.4.5.5.   Effects on Animals
    
          There has been little work focusing on animal indicators of PM effects in the field. However,
    there have been several recent studies on snails, amphibians, earthworms, and bivalves that are
    discussed below.
          Bioindicator organisms can be especially useful for monitoring PM effects over geographical
    and temporal scales. Terrestrial invertebrates have been used to monitor contaminants in both air and
    soil.  Snails (Helix sp.) accumulate trace metals  and agrochemicals, and can be used as effective
    biomonitors for urban air pollution (Beeby and Richmond,  2002,  155680; Regoli et al.,  2006,
    156046; Viard et al., 2004, 055675). Demonstrated biological effects include growth inhibition,
    impairment of reproduction, and induction of metallothioneins that are involved in metal
    detoxification (Gomot-de and Kerhoas, 2000, 155798; Regoli et al., 2006, 156046). The use of
    sentinel species to detect the effects of complex mixtures of air pollutants is of particular value
    because the chemical constituents are difficult to characterize, exhibit varying bioavailability, and are
    subject to various synergistic effects.
    
          Regoli  et al.  (2006, 156046) caged land snails (Helix aspersa) at five locations in the urban
    areas of Ancona, Italy. After four weeks of exposure to ambient air pollution, the snails were
    analyzed for trace metals and PAHs. Biomarkers were measured that correlated with contaminant
    accumulation, including concentrations of metallothioneins, activity of biotransformation enzymes,
    and peroxisomal proliferation. In addition,  indicators of oxidative stress were measured, such as
    oxyradical scavenging capacity, onset of cellular damage, and loss of DNA integrity. Results
    documented substantial accumulation of metals and PAHs in snail digestive tissues in urban areas
    having high traffic congestion.  Cellular reactivity was also found, suggesting that this species is an
    effective bioindicator for multipollutant air quality and PM monitoring.
          Some amphibian ecotoxicological research has focused on heavy metal exposure.  Contaminant
    uptake can occur by oral, pulmonary, and dermal exposure (James et al., 2004, 155874; Johnson et
    al., 1999, 155880; Lambert, 1997, 155916). This is potentially important because of documented
    declines in amphibian populations in the U.S. and elsewhere in recent decades (Houlahan et al.,
    2000, 155853). Toads were shown to be fairly tolerant of Cd exposure (James et al., 2004, 155874).
    It is not clear whether current amounts of terrestrial metal contamination pose an increased risk to
    amphibians in general.
          Estuarine and marine bivalves provide potential bioindicators for Hg bioaccumulation. For
    example, Coelho et al. (2006, 190181) investigated Hg concentrations in Scrobicularia plana, a
    long-lived,  deposit-feeding bivalve in southern  Europe. Annual bioaccumulation rates were shown to
    be strongly correlated with Hg  concentrations in suspended particulate matter (SPM),  a response to
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    their deposit-feeding tactics (Verdelhos et al., 2005, 190497). The ability to predict annual
    accumulation rates for indicator species, such as this bivalve, may facilitate management actions to
    avoid deleterious effects on humans through consumption of bivalves above a certain age/size class.
          Earthworms often constitute a large percentage of soil animal biomass and they are considered
    to be relatively sensitive indicators of soil metal contamination. They are continuously exposed to
    the soil via dermal contact in the soil solution or ingestion of large quantities of soil pore water,
    polluted food and/or soil particles (Lanno et al., 2004, 190415). Hobbelen et al. (2006, 190371)
    determined the important metal pools for bioaccumulation by earthworms Lumbricus rubellus,
    which live in the upper 5cm of soil and Aporrectodea caliginosa, which live in the upper 25 cm of
    soil. Soil concentration explained much of earthworm concentrations, however Cd concentration in
    A. calinginosa was best explained by pore water concentrations and no variable tested explained Zn
    tissue concentrations. Massicotte et al. (2003, 155968) compared the cell viability and phagocytic
    potential of three earthworm species (Lumbricus terrestris, Eisenia andrei, andAporrectodea
    tuberculatd) in response to atmospheric emissions of metals from a cement factory in Quebec,
    Canada. Cell viability actually increased in proximity (0.5 km) to the cement factory for A.
    tuberculata, and this might have been due to beneficial effects of increased Ca deposition. There
    were no significant differences observed for the other two species (Massicotte et al., 2003,  155968).
          Biogeochemical cycling of Hg in the Arctic has  been investigated, in part because observed
    Hg concentrations in marine animals may pose health  risks for local human populations. The lifetime
    of gaseous elemental Hg (GEM) in the atmosphere, which constitutes about 95% of atmospheric Hg,
    is generally about one year (Lin and Pehkonen, 1999, 190426). However, during spring (typically
    March through June), the lifetime of GEM in the Arctic is much shorter, and atmospheric GEM can
    be depleted in less than one day during atmospheric Hg depletion episodes (AMDE) (Lindberg et al.,
    2002, 190429: Skov et al., 2004, 190481). During the AMDE, GEM  is rapidly oxidized to reactive
    gaseous Hg that can be deposited to the ground  surface (Skov et al., 2004, 190481). Because of the
    increased solar flux to the Arctic during spring and seasonal melting  of sea ice, there may be an
    increased efficiency of Hg bioaccumulation in Arctic food webs than would be expected based on
    data collected  at mid-latitudes. Skov et al. (2004, 190481) developed a simple parameterization for
    AMDE and included it in the Danish Eulerian Hemispheric Model (DEHM). The model was shown
    to reproduce the general structure of AMDE, suggesting that the limiting factor for AMDE may be
    the surface temperature of sea ice.
    
    
    9.4.5.6.   Biomagnification across Trophic Levels
    
          Biomagnification is the progressive accumulation of chemicals with increasing trophic level
    (LeBlanc, 1995,  155921). Organic Hg is the most likely metal to biomagnify, in part because
    organisms can efficiently assimilate methylmercury and it is slowly eliminated (Croteau et al., 2005,
    156373; Reinfelder et al., 1998, 156047). Of the trace  metals, there is also evidence that Cd, Pb, Zn,
    Cu and Se biomagnify.
          The study  of trophic transfer and biomagnification is limited by the  difficulty in discriminating
    food webs and the uncertainty associated with assignment of trophic position to individual  species
    (Croteau et al., 2005, 156373). Use of stable isotopes can help to establish linkages. However, it is
    difficult to determine the extent to which biomagnification occurs in  a given ecosystem without
    thoroughly investigating physiological biodynamics, habitat, food web structure, and trophic position
    of relevant species. Thus, development of an understanding of ecosystem complexity is necessary to
    determine what species might be at greatest risk from toxic metal exposure (Croteau et al.,  2005,
    156373).
    
    
          Terrestrial
    
          Bioaccumulation of heavy metals can occur through the plant-herbivore and litter-detrivore
    food webs. The U.S. EPA (2004, 056905) concluded that Cd and Zn can bioaccumulate in
    earthworms. Other invertebrates inhabiting soil  litter may also accumulate metals. Although food
    web accumulation of a metal may not result in mortality, it might reduce breeding potential or result
    in other non-lethal effects that adversely affect organism responses to environmental cues.
          Metal accumulation in litter can be found mainly around brass works, cement factories, and Pb
    and Zn smelters. Organisms that feed  on earthworms living in soils with elevated metal
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    concentrations may also accumulate Pb and Zn. Increased concentrations of heavy metals have been
    found in a variety of mammals living in areas with elevated heavy metal concentrations in the soils.
          The transfer of metals from plants to terrestrial snails is an interesting system for
    biomagnifications because snails accumulate metals in their soft tissue and can contribute
    significantly to the transfer of pollutants to primary consumers and terrestrial predators (Dallinger et
    al., 2001, 192109). Notten et al.  (2005, 190461) studied the transfer of Cu, Zn, Cd and Pb in
    terrestrial soil-plant-snail food chains in metal-polluted soils of the Netherlands. The food chain
    included perennial plant species Urtica dioica and the herbivorous snail Cepaea nemoralis. The
    transfer of metal from the soil to the plant compartment was low (coefficient of determination R2 =
    0.20). Total concentration of metals in soils was a poor predictor of leaf concentration. Low metal
    concentration in the leaves was thought to be  due to low pore water metal concentrations and was
    also thought to be partly caused  by low translocation from roots within the plant. The Cu, Zn and Cd
    concentrations in the  snails were always higher than concentrations in the leaves indicating
    bioaccumulation. The metal transfer from the leaf to snail was highest among all routes tested,
    suggesting that transfer from diet is important. Similar results were found by Beeby and Richmond
    (2002, 155680) with the snail, Helix aspersa,  and the plant, Taraxacum sp., for Zn, Pb, Cd, but not
    for Cu.
          Many types of predators including shrews, thrushes and beetle larvae include snails as part of
    their diet (Gomot-De and Pihan, 2002, 190357: Seifert et al., 1999, 190480).  Seifert et al. (1999,
    190480) found the shrews eating snails with elevated Cd had critical levels of Cd in their kidneys.
    Scheifler et al. (2007, 190379) found that Cd in snails lead to toxic levels in beetle larvae that caused
    increased amounts of mortality.
    
    
          Aquatic
    
          In general, it has been assumed that metal biomagnification in aquatic ecosystems is an
    exception rather than the rule (Gray, 2002, 155806). More recent research has demonstrated aquatic
    biomagnification of certain metals. For example, Stewart et al. (2004, 156097) used stable isotopes
    of C and N to show biomagnification of Se in San Francisco Bay food webs. Croteau et al. (2005,
    156373) identified trophic position of estuarine organisms and food web structure in the delta of San
    Francisco Bay to document Cd biomagnification in invertebrates that live on macrophytes and also
    in fish. Concentrations of Cd were biomagnified 15 times within two trophic links in each food web.
    In contrast, no tendency towards biomagnification was observed for Cu.
          In aquatic ecosystems, biomagnification of trace metals does not necessarily occur. Nguyen et
    al. (2005, 155997) found biodiminution for most metals in Lake Balaton, Hungary, with the
    exception of slight enrichment of Zn from PM to zooplankton and of Cd from sediment to mussels.
          Once transported to aquatic ecosystems, trace metals often preferentially bind to sediment
    particles. Some of these sediment-bound metals may be unavailable to biota; in contrast, metals
    bound to sediment organic matter may exhibit varying degrees of bioavailability (Di Toro et al.,
    2005, 155750). Piol et al.  (2006, 156028) studied the bioavailability of sediment-bound Cd to the
    freshwater oligochaete Lumbriculus variegatus. They found that Cd uptake depended on the amount
    of free dissolved Cd(II), and the Cd contribution from sedimentary particles to biological uptake was
    negligible.
          Marine bivalve mollusks bioaccumulate trace metals and other contaminants (LaBrecque et
    al., 2004, 155913) and therefore may be used as bioindicators of contamination. In addition, they
    constitute an important link to human health by virtue of their importance as a food source
    (Cheggour et al., 2005,  155723:  Li et al., 2002, 156691).
    
    
    9.4.5.7.   Effects near Smelters and  Roadsides
    
          The high PM concentrations in proximity to mining, smelting, roadsides and other industrial
    sources result in heavy metal loadings that may be particularly damaging to nearby ecosystems.
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          Smelters
    
          The Harjavalta region is one of the most intensively studied heavy metal polluted areas in the
    world. Kiikkila et al. (2003, 156637) reviewed available data on heavy metal deposition and
    environmental effects in this area. Emissions from the smelter were as high as 1,100 t/yr of dust, 140
    t/yr Cu, 96 t/yr Ni, 162 t/yr Zn, and 94 t/yr Pb in 1987. Deposition amounts decreased substantially
    after 1990, to only a few percent of the amounts that occurred during the 1980s.
          Kiikkila (2003, 156637) investigated the  effects of heavy metal pollution in proximity to a
    Cu-Ni smelter at Harjavalta, Finland. The deposition of heavy metals increased within 30 km of the
    smelter. Only slight changes in the understory vegetation were observed at distances greater than 8
    km from the smelter. At 4 km distance, species  composition of vegetation, insects, birds, and soil
    microbiota changed and tree growth was reduced. Within about 1 km, only the most resistant
    organisms were surviving.
          The number of soil organisms clearly decreased and their community structure was altered
    close to the Harjavalta smelter (Kiikkila, 2003,  156637). However, this  effect was only pronounced
    within about 2 km of the smelter. This  suggests that the soil microfauna are relatively resistant to
    metal pollution effects.
          Soil microbial activity decreased close to the Harjavalta smelter (Kiikkila, 2003, 156637). as
    reflected by microbial respiration, distribution of species within physiological groups, and microbial
    and fungal biomass. The fungi appeared to be more  sensitive to metal contamination than the
    bacteria (Pennanen et al., 1996,  156016). The rate of litter decomposition decreased, causing an
    accumulation of needle litter on top of the forest floor near the smelter (Fritze et  al., 1989, 079635).
          Inhibition of nutrient cycling and displacement by Cu and Ni of base cations from cation
    exchange sites on the soil resulted in a decrease in base cation concentrations in the organic soil
    layer (Derome  and Lindroos, 1998, 155749; Kiikkila, 2003, 156637) close to the Harjavalta smelter.
    In addition, Mg, Ca, and Mn concentrations in Scots pine (Pinus sylvestris) needles were low, and
    this was attributed by Kiikkila (2003,  156637) to the toxic effects of Cu and Ni to plant fine roots
    and also to ectomycorrhizal root tips (Helmisaari et  al., 1999, 155836). Nutrient translocation during
    fall was also affected close to  the smelter; as a consequence needle concentrations of K were
    relatively high (Nieminen et al., 1999,  155998).
          Tree growth (Scots pine) has  been poor (Malkonen et al., 1999, 155961) and most vegetation
    was absent within 0.5 km of the smelter. Effects on plant species occurrence close to the smelter
    were almost entirely negative. In contrast, some animal species responded positively, including a leaf
    miner, three species of aphid,  and some ants, beetles, and spiders.
          Salemaa et al. (2004, 156069) investigated heavy metal concentrations in understory plant
    species growing at varying distances from the Harjavalta Cu-Ni smelter. Heavy metal concentrations
    (except Mn) were highest in bryophytes, followed by lichens, and were  lowest in vascular plants.
    Vascular plants are generally able to restrict the uptake of toxic elements, and therefore were able to
    grow closer to the smelter than lichens. A pioneer moss (Pohlia nutans) was unusual in that it
    survived close to the smelter despite its accumulation of high amounts of Cu  and Ni.
          Changes in breeding success of cavity-nesting passerine birds close to the Harjavalta smelter
    were attributed to habitat changes in response to metal toxicity (Eeva et al., 2000, 155761; Kiikkila,
    2003, 156637). Calcium supply  is also well known to be important for breeding success in passerine
    bird species. Eggshell thickness, egg size, clutch size,  and hatchability of pied flycatcher (Ficedula
    hypoleucd) were found to be depressed near the Cu smelter at Harjavalta, SW Finland (Eeva and
    Lehikoinen, 2004,  155762). Availability of Ca-rich food to the birds was estimated by counting snail
    shells in the nests postfledging. The number of  snail shells correlated positively with the Ca
    concentration of nestling feces and adult breeding success. In addition, the negative impact of Cu on
    the number of fledglings was stronger  at locations where Ca concentration was low (Eeva and
    Lehikoinen, 2004,  155762).
          Documentation of effects  on individual species, such as was reported above, does not reveal
    what the impacts might be on ecosystem function. Nevertheless, the mere fact that multiple species,
    operating at different trophic levels, have been shown to be affected by the ambient deposition in
    proximity to the smelter  suggests that effects on ecosystem function may indeed  have occurred.
    More research is needed, however, to fully evaluate  effects on function as opposed to abundance of
    individual species.
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          Roadsides
    
          Heavy metal particles are important constituents of road dust. These particles accumulate on
    the road surface from brake linings, road paint, tire debris, diesel exhaust, road construction
    materials, and catalyst materials. Road dust can be suspended in the atmosphere and contribute
    metals to soil, air, and urban runoff (Adachi and Tainosho, 2004, 081380; Davis et al., 2001,
    024933; Smolders  and Degryse, 2002, 156091). In particular, Zn oxide comprises 0.4-4.3% of tire
    tread (Smolders  and Degryse, 2002, 156091) and tire wear is a substantial source of environmental
    Zn pollution.  Adachi and Tainosho (2004, 081380) used a field emission screening electron
    microscope equipped with an energy dispersive x-ray spectrometer to characterize heavy metal
    particles embedded in tire dust. Samples were classified into four likely source categories, based on
    cluster analysis. Based on morphology and chemical composition, the samples were identified as
    having derived from yellow paint (CrPbO4 particles), brake dust (particulate Ti, Fe, Cu, Sb, Zr, Ba
    and heavy minerals [Y, Zr, La, Ce]), and tire tread  (Zn oxide).
          Since publication of EPA's 2004 PM criteria assessment, some additional research has been
    conducted on the effects of windblown PM. Effects on physical, chemical, and biological attributes
    of both plants and animals have been documented  (Englert, 2004, 087939; Gleason et al., 2007,
    155794; Kappos et al., 2004, 087922). Experiments by Gleason et al. (2007, 155794) suggest that
    most direct effects on plants of windblown PM originating from on-road surfaces occur within 40 m
    of the source. Windblown PM from roads or agriculture can cover plant photosynthetic structures
    (Sharifi et al., 1999, 156082). cause impact damage (Armbrust and Retta, 2002,  156225). or
    interfere with physiological mechanisms (Burkhardt  et al., 2002,  155708). As previously discussed
    in Section 9.4.5.5, land snails in urban areas have been shown to  be a good indicator of traffic
    pollution.
    
    
    9.4.5.8.   Toxicity to Mosses and Lichens
    
          At the time of the most recent air quality criteria report for PM (U.S. EPA, 2004, 056905).
    trace metal toxicity to lichens had been demonstrated in relatively few cases. Nash (1975, 016763)
    documented Zn toxicity in the vicinity of a Zn smelter near Palmerton, PA. Experimental data had
    suggested that lichen tolerance to Zn and Cd generally ranges between 200 and 600 ppm (Nash,
    1975. 016763).
          The effects of deposited metals on the mosses  have not been well studied. Tremper et al.
    (2004, 156126) exposed mosses of two species to roadside conditions and sampled them over a
    period of 3 mo.  Under field conditions, chlorophyll concentrations  in moss tissue were not affected
    by metal contamination and accumulation
          Mosses and lichens readily take up metals from atmospheric deposition. Otnyukova (2007,
    156009) demonstrated vertical gradients within a coniferous forest canopy in the fruticose lichen
    genus Usnea with respect to lichen thallus morphology and heavy metal concentration. Abnormal
    thalli at the tree-top level contained higher concentrations of Al, Fe, Zn, F, Sr, and Pb. This vertical
    pattern within the tree canopy is in general accordance with known deposition of PM to plants
    (Otnyukova, 2007, 156009).
          There is an extensive literature on the use of mosses and lichens for estimating deposition
    (biomonitors) and indicating metal exposure in ecosystems (bioindicators) (see Section 9.4.2.3.).
    9.4.6.  Organic Compounds
          VOCs in the atmosphere are partitioned between the gas and particle phases. As described by
    the U.S. EPA (2004, 056905). the partitioning depends on vapor pressure, temperature, surface area
    of the particles, and the nature of the particles and of the chemical being adsorbed. A wide variety of
    organic contaminants are deposited from the atmosphere. These include chemicals such as DDT,
    PCBs, and PAHs.
          Important organic atmospheric contaminants are generally those that are transported long
    distances in the atmosphere, subsequently deposited into remote locations, and bioaccumulated to
    sufficient concentrations that they can affect humans, wildlife, or other biota (Swackhamer et al.,
    2004, 190488).  Certain physical and chemical properties facilitate the movement of these
    contaminants from land and water surfaces into the atmosphere, provide stability,  and  enhance
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    accumulation in lipids. Some, including the relatively small (up to 4 rings) PAHs degrade relatively
    rapidly in the atmosphere or at the surface subsequent to atmospheric deposition. Below is a
    summary of the findings of the U.S. EPA (2004, 056905). followed by discussion of more recent
    research findings.
          Plants may be used as passive monitors to compare the deposition of organic compounds
    between sites. Vegetation can be used semi-quantitatively to indicate organic pollutant amounts if the
    mechanism of accumulation is considered. Organic compounds can enter the plant via the roots or be
    deposited as particles on the leaves and be taken up through the cuticle or stomata. The pathways
    depend on the chemical and its physical properties. These include, for example, lipophilicity, water
    solubility, vapor pressure, and Henry's law constant. Environmental conditions can also be
    important, including temperature and  organic content of soil, plant species, and the foliar surface
    area and lipid content.
          Organic particulates in the atmosphere are diverse in their makeup  and sources. Vegetation
    itself is an important source of hydrocarbon aerosols. Terpenes, particularly a-pinene, (3-pinene, and
    limonene, released from tree foliage may react in the atmosphere to form submicron particles. These
    naturally generated organic particles contribute significantly to the blue-haze aerosols formed
    naturally over forested areas (Geron et al, 2000, 019095: U.S. EPA, 2004, 056905).
          The low water solubility and high lipo-affinity of many organic xenobiotics control their
    interaction with the vegetative components of natural ecosystems. Foliar  surfaces are covered with a
    waxy  cuticle layer that helps reduce moisture loss and short-wave radiation stress. This epicuticular
    wax consists largely of long-chain esters, polyesters, and paraffins, which accumulate lipophilic
    compounds. Organic air contaminants in the particulate or vapor phase can be adsorbed to, and
    accumulate in, the epicuticular wax of leaf surfaces. Direct uptake of organic contaminants through
    the cuticle and vapor-phase uptake through the stomata are not well characterized for most trace
    organics.
          Soil acts as an important storage compartment for POPs, including PCBs and PAHs. There is a
    continuous process of partitioning between the soil pool and the atmosphere, and this controls the
    regional and global transport of these  compounds  (Backe et al., 2004, 155668; Wania  and Mackay,
    1993, 157110). Over time, POPs move towards equilibrium between the environmental
    compartments, and this process can be described using the fugacity concept (Backe et al., 2004,
    155668; Mackay, 1991, 042941). Fugacity reflects the tendency of a chemical constituent to escape
    one environmental compartment and move to another. When an equilibrium distribution is achieved,
    the fugacity quotient values in each compartment  will be equal. Soil/air partitioning is  controlled by
    a variety  of factors. These include soil properties,  such as organic matter  content, moisture, porosity,
    texture, and structure, as well as the physiochemical properties of the pollutant, including vapor
    pressure and water solubility.
          The accumulation of PAHs in vegetation, due to their lipophilic nature, could contribute to
    human and other animal exposure via food consumption. As a result, plant uptake of PAHs has been
    an important area of research (Gao and Zhu, 2004, 155782). Most bioaccumulation of PAHs by
    plants occurs by leaf uptake (Tao et al., 2006, 156112). Root uptake also occurs. It appears that roots
    preferentially accumulate the lower molecular weight PAHs due to their greater water solubility
    (Wild and Jones, 1992, 156155).
          Various models have been developed to simulate plant uptake of organic contaminants. The
    simple partition-limited model of Chiou et al. (2001, 156342) has been further expanded to increase
    complexity and to include root uptake pathways (e.g., Fryer and Collins, 2003, 156454; Yang et al.,
    2005, 192104; Zhu et al., 2004, 156184).
          In evaluating receptor choice for studies of  contaminant exposure to plants, and  also
    remediation potential, it is important to consider differences among species. For example, Parrish et
    al. (2006, 156014)  assessed the bioavailability of PAHs in soil. During the first growing season,
    zucchini (Cucurbita pepo ssp. pepo) accumulated significantly more PAHs than did other related
    plant species, including up to three orders of magnitude greater concentrations of the six-ring PAHs.
    Parrish et al. (2006, 156014) also noted differences in PAH uptake by two different species of
    earthworm.
          The leaves of Quercus ilex have been shown to readily accumulate PAHs in situ. Young leaves
    accumulated PAHs within three weeks of bud break. Mature leaves showed seasonality, with higher
    PAH concentrations during winter (Alfani et al., 2005, 154319).
          It is difficult to discriminate between PAHs  that are adsorbed to plant root surfaces as opposed
    to those that are actually taken up by the roots. In  general, soil bound PAHs are associated with soil
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    organic matter and are therefore not readily available for root uptake (Fismes et al., 2002, 141156;
    Jiao et al., 2007, 155879). Wild et al. (2005, 156156) used two-photon excitation microscopy to
    visualize the uptake and transport of two PAHs (anthracene and phenanthrene) from a contaminated
    soil into living wheat and maize roots. Jiao et al. (2007, 155879) developed a sequential extraction
    method to discriminate between PAH adsorption in rice roots.
          Maize roots and tops of plants have  been shown to directly accumulate PAHs from aqueous
    solution and from air in proportion to exposure amounts. Root concentration factors are log-linear
    functions of log-based octanol-water partition coefficients (log Kow); similarly, leaf concentration
    factors are log-linear functions of log-based octanol-air partition coefficients (log Koa) (Lin et al.,
    2007, 155933). Although the bulk concentrations of PAHs in various plant tissues can differ greatly,
    the observed differences disappear after they are normalized to lipid content (Lin et al., 2007,
    155933). This suggests that the lipid content of different plant tissues may influence PAH
    distribution within the plant.
          Previously, there was relatively little information available regarding incorporation of
    atmospherically deposited PAHs into aquatic food webs. It is known that PAHs can be transferred to
    higher trophic levels, including fish, and that this transfer can be mediated by aquatic invertebrates,
    which generally comprise an important part offish diets. High mountain lakes  offer an effective
    receptor for quantification of biomagnification in aquatic  ecosystems from atmospheric PM
    deposition. There are typically no sources  of organic contaminants in their watersheds, and
    atmospheric inputs dominate as sources of contamination. In addition, such lakes tend to have
    relatively simple food webs. Vives et al. (2005, 157099) investigated PAH content of brown trout
    (Salmo truttd) and their food items. Total PAH concentrations tended to  be highest in organisms that
    occupy littoral habitats, and lowest in pelagic organisms. This  may reflect more efficient transfer of
    PAHs to underlying sediments in shallower water and associated degradation within the water
    column.
          Some atmospheric organic contaminants have been shown to accumulate in biota at remote
    locations. For example, polybrominated diphenyl ethers (PBDEs), which are man-made chemicals
    used as flame retardants in materials manufacturing, have been found to accumulate in lichens and
    mosses collected at King George Island, maritime Antarctica (Yogui and Sericano, 2008, 189971).
    Because contaminant concentrations were  not statistically different at sites close to and distant from
    human facilities in Antarctica, the authors  concluded that  long-range atmospheric transport was the
    likely primary  source of PBDEs to King George Island. Law et al. (2003, 190420) reviewed
    available data for accumulation of PBDEs and other brominated flame retardants in wildlife. These
    compounds have become widely distributed in the environment, including in the deep-water, oceanic
    food webs.
          Ohyama et al. (2004, 190462) chose salmonid fish, mainly rainbow trout (Oncorhyncus
    mykiss), as an  indicator species to evaluate the transport and bioaccumulation of organochloride
    compounds in the northern and central Sierra Nevada. They found that elevation was an important
    factor affecting residual concentrations of  poly chlorinated biphenyls (PCBs) in fish muscle tissue.
    On this basis, Ohyama et al. (2004,  190462) concluded that PCB  residue in rainbow trout, a widely
    distributed salmonid species, provided a good monitoring tool for studying the effects of
    mountainous topography on the long-range transport and distribution of persistent organic pollutants.
          Semivolatile compounds  can undergo repeated volatilization on surfaces, such as plant foliage,
    in response to diel changes in temperature. As a consequence,  such  compounds can be deposited, re-
    emitted, and re-deposited multiple times. This behavior can cause these  compounds to move large
    distances in a leap-frog fashion (Krupa et al., 2008, 198696). It is believed that POPs can be
    atmospherically transported throughout the world because of their volatility and response to changes
    in temperature. This "global distillation theory"  (Holmqvist et al., 2006, 190380; Wania  and
    Mackay, 1993, 157110) predicts that POPs in the northern hemisphere are generally transported
    towards the Arctic, and in the southern hemisphere they are transported toward the Antarctic. In
    general, POP concentrations measured in the Arctic are higher than in the Antarctic. They have been
    detected in all levels of the Arctic food web (Oehme et al., 1995, 011267). Bioconcentration of
    organochlorines has been shown in the Arctic food web, including fish, seals, and polar bears
    (Oehme et al.,  1995, 011267). Concentrations measured in Arctic polar bears are especially high
    (AMAP, 2004, 190168).
          Holmqvist et al. (2006, 190380) measured levels of PCBs in longfin eels (Anguilla
    dieffenbachii) in 17 streams on the west coast of South Island, New Zealand. The PCBs were at low
    levels, and were believed to originate from atmospheric transport from industrial areas in Asia.
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    Characteristics of the longfin eel that make it susceptible to bioaccumulation of lipophilic persistent
    pollutants include high lipid content (up to 40%), long lifespan (up to 90 yrs), and position near the
    top of the food chain (Holmqvist et al, 2006, 190380).
         Long-range transport of atmospherically deposited contaminants can be augmented by
    biotransport. A good example of this phenomenon was documented by Ewald et al. (1998, 190348).
    who showed that biotransport by migrating sockeye salmon (Oncorhynchus nerkd) in the Copper
    River watershed, Alaska, had a greater influence than atmospheric transport on bioaccumulation of
    PCBs and DDT in lake food webs. Organic pollutants accumulated by salmon during their ocean
    residence were effectively transferred 410 km inland to their spawning lake. Arctic grayling
    (Thymallus arcticus) in the salmon spawning lake were found to contain organic pollutants more
    than twice as high as  arctic grayling in a near-by salmon-free lake. The pollutant composition of the
    grayling in the salmon spawning lake was similar to that of the migrating salmon (Ewald et al., 1998,
    190348), suggesting that salmon migration contributed to bioaccumulation of organic contaminants
    in the lake used for spawning by the salmon.
         An assessment of the ecological effects of airborne metals and SOCs was conducted for eight
    NPs by the Western Airborne Contaminants Assessment Project (WACAP) (Landers et al., 2008,
    191181). From 2002-2007, WACAP researchers conducted analysis of the biological effects of
    airborne contaminants in seven ecosystem compartments: air, snow, water, sediments, lichens,
    conifer needles and fish. The goals were to identify where the pollutants were accumulating, identify
    ecological indicators for those pollutants causing ecological harm, and to determine the source of the
    air masses most likely to have transported the contaminants to the parks.
         The results from WACAP were summarized by Landers et al. (2008, 191181). which
    concluded that bioaccumulation of SOCs  were observed throughout park ecosystems. Vegetation
    tended to accumulate PAHs, CUPs, and HCHs. Conifer needles were a good indicator of pesticides,
    however the ecological consequences of this accumulation are unexamined. SOCs in vegetation and
    air showed different patterns, possibly because each medium absorbs different types of SOCs with
    varying efficiencies. Mean ammonium nitrate concentration in ambient fine particulates  <2.5 (im
    diameter was a good predictor of dacthal, endosulfan, chloradane, trifluralin, DDT and PAH
    concentrations in vegetation.
         Concentrations of SOCs were five to seven orders of magnitude higher in fish tissue than in
    sediments. Fish accumulated more PCBs, chlordanes, DDT and dieldrin than vegetation. Fish lipid
    and age were the most reliable predictors  of SOC concentrations. Most fish appeared normal during
    field necropsies; however, individuals with both male and female reproductive organs were collected
    at two sites. The incidence of this condition has increased since the pre-organic pollutant era.
    Additionally, elevated concentrations of vitellogenin, a female protein involved in egg production,
    were found in male fish from three sites, and directly related to the concentration of several
    organochlorines at one site.
         The lake sediment records showed steadily increasing mercury deposition over time at lakes in
    two parks, Mt. Ranier NP and Rocky Mountain NP Apportionment of the mercury to its atmospheric
    sources is not quantified at this time; however,  the pattern in the sediment suggests a local source
    rather than  a global source. Mercury concentrations in fish exceeded contaminant health thresholds
    for some piscivorous fish, mammals and birds in most parks. The average mercury concentration in
    fish from one site and individual fish from three additional sites exceeded the U.S. EPA contaminant
    health thresholds for humans.
         Although this assessment focuses on chemical species that are components of PM, it does not
    specifically assess the effects of particulate versus gas-phase forms; therefore, in most cases it is
    difficult to apply the results to this assessment based on particulate concentration and size fraction.
    
    
    9.4.7.  Summary of Ecological  Effects of PM
    
         Ecological effects of PM include direct effects to metabolic processes of plant foliage;
    contribution to total metal loading resulting in alteration of soil biogeochemistry and microbiology,
    plant and animal growth and reproduction; and contribution to total organics loading resulting in
    bioaccumulation and biomagnification across trophic levels. These effects were well-characterized in
    the 2004 PM AQCD (U.S.  EPA, 2004, 056905). Thus, the summary below builds upon the
    conclusions provided in that review.
         PM deposition comprises a heterogeneous mixture of particles differing in origin,  size, and
    chemical composition. Exposure to a given concentration of PM may, depending on the mix of
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    deposited particles, lead to a variety of phytotoxic responses and ecosystem effects. Moreover, many
    of the ecological effects of PM are due to the chemical constituents (e.g., metals, organics, and ions)
    and their contribution to total loading within an ecosystem.
          Investigations of the direct effects of PM deposition on foliage have suggested little or no
    effects on foliar processes, unless deposition levels were higher than is typically found in the
    ambient environment. However, consistent and coherent evidence of direct effects of PM has been
    found in heavily polluted areas adjacent to industrial point sources such as limestone quarries,
    cement kilns, and metal smelters (Sections 9.4.3 and 9.4.5.7). Where toxic responses have been
    documented, they generally have been associated with the acidity, trace metal content, surfactant
    properties, or salinity of the deposited materials.
          An important characteristic of fine particles is their ability to affect the flux of solar radiation
    passing through the atmosphere, which can be considered in both its direct and diffuse components.
    Foliar interception by canopy elements occurs for both up- and down-welling radiation. Therefore,
    the effect of atmospheric PM on atmospheric turbidity influences canopy processes both by radiation
    attenuation and by changing the efficiency of radiation interception in the canopy through
    conversion of direct to diffuse radiation. Crop yields can be sensitive to the amount of radiation
    received, and crop losses have been attributed to increased regional haze in some areas of the world
    such as China. On the other hand, diffuse radiation is more uniformly distributed throughout the
    canopy and may increase canopy photosynthetic productivity by distributing radiation to lower
    leaves. The enrichment in photosynthetically active radiation (PAR) present in diffuse radiation may
    offset a portion of the effect of an increased atmospheric albedo due to atmospheric particles. Further
    research is needed to determine the effects of PM alteration of radiative flux on the growth of
    vegetation in the U.S.
          The deposition of PM  onto vegetation and soil, depending on its chemical composition, can
    produce responses within an ecosystem. The ecosystem response to pollutant deposition is a direct
    function of the level of sensitivity of the ecosystem and its ability to ameliorate resulting change.
    Many of the most important  ecosystem effects of PM deposition occur in the soil. Upon entering the
    soil environment, PM pollutants can alter ecological processes of energy flow and nutrient cycling,
    inhibit nutrient uptake,  change ecosystem structure, and affect ecosystem biodiversity. The soil
    environment is one of the most dynamic sites of biological interaction in nature. It is inhabited by
    microbial communities of bacteria, fungi, and actinomycetes, in addition to plant roots and soil
    macro-fauna. These organisms are essential participants in the nutrient cycles that make elements
    available for plant uptake. Changes in the soil environment can be important in determining plant
    and ultimately ecosystem response to PM inputs.
          There is strong and consistent evidence from field and laboratory experiments that metal
    components of PM alter numerous aspects of ecosystem structure and function. Changes in the soil
    chemistry, microbial communities and nutrient cycling,  can result from the deposition of trace
    metals. Exposures to trace metals are highly variable, depending on whether deposition is  by wet or
    dry processes. Although metals can cause phytotoxicity at high concentrations, few heavy metals
    (e.g., Cu, Ni, Zn) have been documented to  cause direct phytotoxicity under field conditions.
    Exposure to coarse particles  and elements such as Fe and Mg are more likely to occur via  dry
    deposition, while fine particles, which are more often deposited by wet deposition, are more likely to
    contain elements such as Ca, Cr, Pb, Ni, and V. Ecosystems immediately downwind of major
    emissions sources can receive locally heavy deposition inputs. Phytochelatins produced by plants as
    a response to sublethal  concentrations of heavy metals are indicators  of metal stress to plants.
    Increased concentrations of phytochelatins across regions and at greater elevation have been
    associated with increased amounts of forest injury in the northeastern U.S.
          Overall, the ecological evidence is sufficient to conclude that 3 Causal relationship JS
    likely to exist between deposition of PM and a variety of effects on individual organisms
    and  ecosystems, based on information from the previous review and limited new
    findings in this review. However, in many cases, it is difficult to characterize the nature and
    magnitude of effects and to quantify relationships between ambient concentrations of PM  and
    ecosystem response due to significant data gaps and uncertainties as well as considerable variability
    that exists in the components of PM and their various ecological effects.
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    9.5.  Effects on Materials
    
          Effects of air pollution on materials are related to both aesthetic appeal and physical damage.
    Deposited particles, primarily carbonaceous compounds, cause soiling of building materials and
    culturally important items, such as statues and works of art. Physical damage from dry deposition of
    PM also can accelerate natural weathering processes. The major deterioration phenomenon affecting
    building materials in response to atmospheric deposition  is most likely sulfation, leading to
    secondary salt crystallization which forms gypsum (Marinoni et al., 2003, 092520).
          This section (a) summarizes information on exposure-related effects on materials associated
    with particulate pollutants as addressed in the 2004 PM AQCD (U.S. EPA, 2004, 056905): and (b)
    presents relevant information derived from very limited research conducted and published since
    completion of that document. Most recent work  on this topic has been conducted outside the U.S.
          There is a variety of factors that contribute to the deterioration of monuments and buildings of
    cultural significance. They include: (1) biodeterioration processes; (2) weathering  of materials
    exposed to the air; and (3) air pollution from both anthropogenic and natural sources (Herrera and
    Videla, 2004, 155843). Because of the diversity  in climate, proximity to marine aerosol sources, and
    pollution of various types, the magnitude and relative importance of these causal agents vary by
    location.
          Much existing literature  on damage to structural  materials of cultural heritage has not seriously
    considered the importance of biodeterioration processes and the relationship that often exists
    between environmental characteristics and the microbial  communities that colonize monuments and
    buildings. In general, high humidity, high temperature, and air pollution often enhance the
    biodeterioration hazard. Herrera and Videla (2004, 155843) concluded that heterotrophic bacteria,
    fungi, and cyanobacteria were the main microbial colonizers of buildings that they investigated in
    Latin America. Their analyses suggested that the major deterioration mechanism of limestone at the
    Mayan site of Uxmal in a non-polluted rural environment was biosolubilization induced by
    metabolic acids produced by bacteria and fungi.  The rock decay at Tulum, near the seashore, was
    mainly attributed to the marine influence. At Medellin, it appeared that biodeterioration effects from
    microbes synergistically enhanced the effects of atmospheric factors on material decay. Deterioration
    of structural material in the  Cathedral of La Plata, located in a mixed urban/industrial environment,
    was attributed mainly to atmospheric pollutants (Herrera and Videla, 2004, 155843).
          Ambient particles can cause soiling of man-made surfaces.  Soiling generally is considered an
    optical effect. Soiling changes the reflectance from opaque materials and reduces the transmission of
    light through transparent materials. Soiling can represent a significant detrimental  effect, requiring
    increased frequency of cleaning of glass windows and concrete structures, washing and repainting of
    structures, and, in some cases, reduces the useful life of the object. Particles, especially carbon, may
    also help catalyze chemical reactions that result in the deterioration of materials (U.S. EPA,  2004,
    056905).
          Soiling is dependent on atmospheric particle concentration, particle size  distribution,
    deposition rate, and the horizontal or vertical orientation  and texture of the exposed surface (Haynie,
    1986, 157198). The chemical composition and morphology of the particles and the optical properties
    of the surface being soiled will determine the time at which soiling is perceived by human observers
    (Nazaroff and Cass, 1991, 044577).
          Perm et al. (2006, 155135) reported development of a simple passive particle collector for
    estimating dry deposition to objects of cultural heritage. The observed mass of deposited particles
    mainly belonged to the coarse particulate mode.  The sampler collects particles  from all directions.  It
    replicates at least some of the complexity of particle deposition to actual objects, and is easier to
    analyze than a precious object (Perm et al., 2006, 155135).
          Soiling of urban buildings constitutes a visual nuisance that leads to the loss of architectural
    value. Soiling can include reversible darkening of the building surfaces and also irreversible damage.
    Water runoff patterns on the building surfaces are influenced by the type of surface material,
    architectural elements, and climate. Therefore, soiling does not occur uniformly across the building.
    Public perception of soiling entails complex interactions  between the extent of soiling, architecture,
    and aesthetics (Grossi  and Brimblecombe, 2004, 155813).
          One of the most significant air pollution damage features affecting urban buildings and
    monuments is the formation of black crusts. Quantification of different forms of carbon in black
    crusts is difficult. There is often a carbonate component which is derived from  the building material,
    plus  OC and EC, derived from air pollution. EC  is considered to be a tracer for combustion sources,
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    whereas OC may derive from multiple sources, including atmospheric deposition of primary and
    secondary pollutants, and the decay of protective organic treatments (Bonazza et al., 2005, 155695).
    Bonazza et al. (2005, 155695) quantified OC and EC in damage layers on European cultural heritage
    structures. OC predominated over EC at almost all locations investigated. Traffic appeared to be the
    major source of fine carbonaceous particles, with organic matter as the main component (Putaud et
    al., 2004, 055545). Viles and Gorbushina (2003, 156138) found that soiling in Oxford, U.K.  showed
    a relationship with traffic and NO2 concentrations.
          In addition to the soiling effects of EC, much soiling appears to be largely of microbiological
    origin (Viles  and Gorbushina, 2003, 156138). Microbial biofilms, composed mainly of fungi, can
    stain exposed rock surfaces with yellow, orange, brown, gray, or black colors. Microorganisms may
    be able to trap PM  more efficiently than the stone surface itself. In addition, microbial growth may
    be stimulated by organic or nutrient constituents in PM deposition.
          Viles et al. (2002, 156137) investigated the nature of soiling on limestone tablets in relation to
    ambient air pollution and climate at three contrasting sites in Great Britain over periods of one to
    eight years. Spectrophotometer and microscope observations suggested that there were not consistent
    trends in soiling over time at the study sites. Each site behaved differently in terms of the temporal
    development of soiling and the differences between sheltered and exposed limestone tablets. In
    addition, organisms played important roles in the soiling response, even at the highly polluted site.
          Some work has been conducted on public perception regarding the lightness of historic
    buildings and the aesthetic need for cleaning  subsequent to soiling by air pollution. Brimblecombe
    and Grossi (2005, 155703) found a strong relationship between the perceived lightness of a building
    and the opinion that it was dirty. This relationship was used to establish levels of blackening that
    might be publicly acceptable.
          Recently, the importance of organic contaminant deposition to the overall air pollution damage
    to building materials has been recognized. Low molecular weight organic anions such as  formate,
    acetate, and oxalate are ubiquitous in black crusts in damage layers on stones and mortars sampled
    from monuments and buildings throughout Europe (Sabbioni et al., 2003, 049282). This has been
    observed at urban,  suburban, and rural sites.
    
    
    9.5.1.  Effects  on  Paint
    
          Studies have evaluated the soiling effects of particles on painted surfaces (U.S. EPA, 2004,
    056905). Particles composed of EC, acids, and various other constituents are responsible for the
    soiling of structural painted surfaces. Coarse-mode particles (>2.5 urn) initially contribute more
    soiling of horizontal and vertical painted surfaces than do fine-mode particles (<2.5 um), but are
    more easily removed by rain (Haynie and Lemmons,  1990, 044579). Rain interacts with coarse
    particles, dissolving the particle and leaving stains on  the painted surface (Creighton et al., 1990,
    044578; Haynie and Lemmons, 1990, 044579). Particle deposition contributes to increased
    frequency of cleaning of painted surfaces and physical damage to the painted surface. Air pollution
    affects the durability of paint finishes by promoting discoloration, chalking, loss of gloss, erosion,
    blistering, and peeling (U.S. EPA, 2004, 056905). There have been no new developments in this field
    subsequent to the review of the U.S. EPA (2004, 056905).
    
    
    9.5.2.  Effects  on  Metal Surfaces
    
          Metals undergo natural weathering processes. The effects of air pollutants on natural
    weathering processes depend on the nature of the pollutant(s), the deposition rate, and the presence
    of moisture (U.S. EPA, 2004, 056905). Pollutant effects on metal surfaces are governed by such
    factors as the presence of protective corrosion films and surface electrolytes, the orientation of the
    metal surface, and surface moisture. Surface moisture facilitates particulate deposition and promotes
    corrosive reactions. Formation of hygroscopic salts increases the duration of surface wetness and
    enhances corrosion.
          A corrosion film, such as for example the rust layer on the surface of some metals,  may
    provide some protection against further corrosion. Its  effectiveness in retarding the corrosion process
    is affected by the solubility of the corrosion layer and  the pollutant  exposure. Other than the  effects
    of acidifying compounds, there has not been additional research conducted in recent years on the
    effects of PM deposition on metal corrosion.
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    9.5.3.  Effects on Stone
    
          Air pollutants can enhance the natural weathering processes on building stone. The
    development of crusts on stone monuments has been attributed to the interaction of the stone's
    surface with pollutants, wet or dry deposition of atmospheric particles, and dry deposition of gypsum
    particles. Because of a greater porosity and specific surface, mortars have a high potential for
    reacting with environmental pollutants (Zappia et al., 1998, 012037).
          Most research evaluating the effects of air pollutants on stone structures has concentrated on
    gaseous pollutants (U.S. EPA, 2004, 056905). The dark color of gypsum is attributed to soiling by
    carbonaceous particles. A lighter gray colored crust is attributed to soil dust and metal  deposits
    (Ausset et al., 1998, 040480: Camuffo, 1995, 076278: Lorusso et al., 1997, 084534: Moropoulou et
    al., 1998, 040485). Lorusso et al. (1997, 084534) attributed the need for frequent cleaning and
    restoration of historic monuments in Rome to exposure to total suspended particulates.
          Grossi et al. (2003, 155812) investigated the black soiling rates of building granite, marble,
    and limestone in two urban environments with different climates. Horizontal specimens were
    exposed, both sheltered and unsheltered from rainfall. Limestone showed soiling proportional to the
    square root of the time of exposure, but granite and marble did not.
          Black soiling is caused mainly by particulate EC  (PEC).  For that reason, it is most prevalent in
    urban environments due to the formation of carbonaceous fine particles from the incomplete
    combustion of fossil fuels. Traffic emissions, especially from diesel engines, and wood burning are
    important sources of PEC (Grossi et al., 2003, 155812).
          Kamh (2005, 155888) studied the effects of weathering on Conway Castle, an historical
    structure in Great Britain built about 1289 AC. The weathering was identified as honeycomb,
    blackcrust, exfoliation, and discoloration, with white salt efflorescence at some parts. These features
    are diagnostic for salt weathering (Goudie et al., 2002, 156486). and this was confirmed by
    laboratory analyses, including scanning electron microscopy and x-ray diffraction. The authors
    concluded that the salt was derived from three sources:  sea spray, chemical alteration of the
    carbonate in mortar into SO42~ salts by acidic deposition, and wet deposition of air pollutants on the
    stone surface. The salt content on the rock surface fills the rock pores and then exerts high pressure
    on the rock texture due to hydration of the salt in the cold humid environment. In particular, CaSO4
    and Na2SO4 exert enough pressure on hydration as to deteriorate construction rock at both the micro-
    and macroscale (Moses  and Smith, 1994, 156785).
    
    
    9.5.4.  Summary of Effects on  Materials
    
          Building materials (metals, stones, cements, and paints) undergo natural weathering processes
    from exposure to environmental elements (wind, moisture, temperature fluctuations, sunlight,  etc.).
    Metals form a protective film of oxidized metal (e.g., rust) that slows environmentally induced
    corrosion. However, the natural process of metal corrosion is enhanced by exposure to
    anthropogenic pollutants. For example, formation of hygroscopic salts increases the duration of
    surface wetness and enhances corrosion.
          A significant detrimental effect of particle pollution is the soiling of painted surfaces and other
    building materials. Soiling changes the reflectance of opaque materials and reduces the transmission
    of light through transparent materials. Soiling is a degradation process that requires remediation by
    cleaning or washing, and, depending on the soiled surface, repainting. Particulate deposition can
    result in increased cleaning frequency of the exposed surface and may reduce the usefulness of the
    soiled material. Attempts have been made to quantify the pollutant exposure at which materials
    damage and soiling have been perceived. However, to date, insufficient data are available to advance
    the knowledge regarding perception thresholds with respect to pollutant concentration, particle size,
    and chemical composition. Nevertheless, the evidence is sufficient to conclude that 3 C3US3I
    relationship exists between PM and effects on materials.
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           192085
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         Annex A. Atmospheric  Science
    A.1. Ambient Air Particle Monitoring
    
    A.1.1. Measurements and Analytical Specifications
    Table A-1.   Summary of integrated and continuous samplers included in the field comparison.
    Abbreviation Instrument
    Manufacturer/ Research Institute
    INTEGRATED PARTICLE OR GAS/PARTICLE INSTRUMENTS
    Dichot Dichotomous Sampler with Virtual Impactor
    AND-241 Dichot Thermo Andersen Series 241 Dichotomous Sampler
    AND-246 Dichot Thermo Andersen SA-246B Dichotomous Sampler
    FRM~hlVOL1° Thermo Andersen GMW-1200 HiVol PM10FRM Sampler
    ARA-PCM ARA Particle Composition Monitor
    CMU CMU Speciation Sampler
    DRI-SFS DRI Sequential Filter Sampler
    HEADS (or HI) Harvard EPAAnnular Denuder System (or Harvard Impactor)
    IMPROVE_SSb IMPROVE Speciation Sampler
    URG-3000N" Modified IMPROVE Module C Sampler for Carbon
    MASS-400b URG Mass Aerosol Speciation Sampler Model 400
    MASS-450" URG Mass Aerosol Speciation Sampler Model 450
    MiniVol Battery-Powered Portable Low-Volume Sampler
    or cncc Particle Concentrator-Brigham Young University Organic Sampling
    PC-BOSS Sys(em
    Andersen Instruments (Smyrna, GA)
    Andersen Instruments
    Andersen Instruments
    Andersen Instruments
    Atmospheric Research and Analysis Inc. (Piano, TX)
    Carnegie Mellon University (CMU), (Pittsburgh, PA)
    Desert Research Institute (Reno, NV)
    Harvard School of Public Health (Boston, MA)
    URG Corp. (Chapel Hill, NC)
    URG Corp.
    URG Corp.
    URG Corp.
    Air Metrics Inc. (Eugene, OR)
    Brigham Young University (Provo, UT)
    SAMPLING SYSTEM
    PQ-200 FRM BGI PQ-200 FRM Sampler
    PQ-200 FRMA BGI PQ-200A FRM Audit Sampler
    R&P-ACCU R&P-Automated Cartridge Collector Unit Sampler
    R&P-2000 FRM R&P Partisol-2000 FRM Sampler
    R&P-2000 FRMA R&P Partisol-2000 FRM Audit Sampler
    R&P-2025 Dichotb R&P Partisol 2025 Dichotomous Sequential Air Sampler
    R&P-2025 FRM R&P Partisol-Plus Model 2025 PM25 Sequential Samplers
    R&P-2300b R&P Partisol 2300 Chemical Speciation Sampler
    BGI Inc. (Waltham, MA)
    BGI Inc.
    Rupprecht & Patashnick, Co. (Albany, NY)
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    
     Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
     Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
     developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
    December 2009
    A-1
    

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    Abbreviation Instrument
    RAAS-1 00 FRM Thermo Andersen Reference Ambient Air Sampler Model 1 00
    Manufacturer/ Research Institute
    Andersen Instruments
    FRM SAMPLER
    RAAS-200 FRM Thermo Andersen RAAS Model 200 FRM Audit Sampler
    RAAS-300 FRM Thermo Andersen RAAS Model 300 FRM Sampler
    RAAS-400b Thermo Andersen RAAS Model 400 Speciation Sampler
    SASSb MetOne Spiral Ambient Speciation Sampler
    SCS PM2.5 Sequential Cyclone Sampler
    URG-PCMb URG Particle Composition Monitor
    VAPS URG Versatile Air Pollution Sampler
    Andersen Instruments
    Andersen Instruments
    Andersen Instruments
    Met One Instruments (Grants Pass, OR)
    New York University (New York, NY)
    URG Corp. (Chapel Hill, NC)
    URG Corp.
    CONTINUOUS MASS INSTRUMENTS
    BAM B-Attenuation Monitor Model 1 020
    nano-BAM Met One BAM Model 1 020 with 1 50 nm impactor
    CAMM Continuous Ambient Mass Monitor
    p, yg Real-Time Ambient Mass Sampler (modified Tapered Element
    Oscillation Microbalance with diffusion denuder and Nation dryer)
    TEOM Tapered Element Oscillating Microbalance
    30 "C-TEOM TEOM operated at 30 °C
    50 °C-TEOM TEOM operated at 50 °C
    SES-TEOM TEOM 1 400a Series with Sample Equilibration System
    D-TEOM Differential TEOM
    FDMS-TEOM Filter Dynamics Measurement System TEOM
    ACCU-TEOM TEOM 1 400 Series with an automated cartridge collection unit
    Met One Instruments
    Met One Instruments
    Developed by Harvard School of Public Health, commercialized
    by Thermo Andersen Instruments; now withdrawn from market
    Brigham Young University
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    Rupprecht & Patashnick, Co.
    CONTINUOUS PARTICLE LIGHT SCATTERING INSTRUMENTS
    Dust Trak Dust Trak nephelometer
    EcoTech EcoTech Model M9003 nephelometer
    NGN NGN-2 nephelometer
    RR-M903 Radiance Research Nephelometer Model M903
    TSI Inc. (Shoreview, MN)
    EcoTech Ry Ltd., Australia (American EcoTech, Warren, Rl)
    Optec Inc. (Lowell, Ml)
    Radiance Research Inc. (Seattle, WA)
    CONTINUOUS ELEMENT INSTRUMENTS
                     Graphite Furnace Atomic Absorption Spectrometry— aerosol
                     collection as preconcentrate slurry
                                                              University of Maryland (College Park, MD)
    SEAS
                     Semicontinuous Elements in Aerosol Sampler
                                                              University of Maryland
    CONTINUOUS NITRATE INSTRUMENTS
    ADI-N
                     Aerosol Dynamics Inc. Flash Volatilization Analyzer
                                                              Aerosol Dynamics Inc. (Berkeley, CA)
    ARA-N
                     Atmospheric Research and Analysis N03-Analyzer
                                                              Atmospheric Research and Analysis Inc.
    R&P-8400N
                     R&P-8400N Flash Volatilization Continuous N03- Analyzer
                                                              Rupprecht & Patashnick, Co.
    CONTINUOUS SULFATE INSTRUMENTS
    ADI-S
                     Aerosol Dynamics Inc. Flash Volatilization Analyzer
                                                              Aerosol Dynamics Inc.
                     Continuous Ambient Sulfate Monitor (prototype of the TE-5020 by
                     Thermo Electron [Franklin, MA])
                                                              Harvard School of Public Health
    R&P-8400S
    R&P-8400S Flash Volatilization Continuous S042~ Analyzer
                                                                               Rupprecht & Patashnick, Co.
    TE-5020
    Thermo Electron Model 5020 S042" Particulate Analyzer
                                                                               Thermo Electron Corp. (Franklin, MA)
    December 2009
                                                 A-2
    

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      Abbreviation
                           Instrument
    Manufacturer/ Research Institute
    CONTINUOUS MULTI-ION INSTRUMENTS
    AIM
    Ambient Ion Monitor Model 9000 (Cf,N02" ,N03",P043",
    S042", NH4+,Na+,Mg2+'K+,Ca24)
                                                                              URG Corp.
    Dionex-IC
                                                     ~,Bf'N03~, P043~, S042~,
                                                                              Dionex CorP'
    ECN
    Energy Research Center of the Netherlands IC-based sampler (Cl,   Energy Research Center of the Netherlands (Petten, the
    N03", S042", NH4+ ,Na+, Mg2+,K+, Ca24)                          Netherlands
    PILS-IC
                                                       '° (C'"' N°2" ' N°3"' P°4 "'
                                                                              Geor9ia lnstitute °f Technology (Atlanta, GA)
                     Texas Tech IC-based sampler (N03, S04~)
                                                             Texas Tech University (Lubbock, TX)
    CONTINUOUS CARBON INSTRUMENTS
    OC and EC
    ADI-C
                     ADI Flash Volatilization Carbon Analyzer
                                                             Aerosol Dynamics Inc.
    RU-OGI
    Rutgers University/Oregon Graduate Institute in-situ carbon analyzer  Rutgers University (Camden, NJ)/Oregon Graduate Institute
    (OC, EC)                                                  (Beaverton, OR)
    R&P-5400
                     R&P-5400 continuous ambient carbon analyzer
                                                             Rupprecht & Patashnick, Co.
    Sunset OCEC
    Sunset Semi-Continuous Real-Time Carbon Aerosol Analysis
    Instrument
                                                                              Sunset Laboratory, Inc. (Tigard, OR)
    EC
    Aethalometer
                                                                              Magee Scientific Co. (Berkeley, CA)
     AE-16
                     Magee AE-16 aethalometer (BC)
                                                             Magee Scientific Co.
     AE-20
                     Magee AE-20 dual wavelength aethalometer (BC)
                                                             Magee Scientific Co.
     AE-21
                     Magee AE-21 dual-wavelength aethalometer (BC)
                                                             Magee Scientific Co.
     AE-31
                     Magee AE-31 seven color aethalometer (BC)
                                                             Magee Scientific Co.
    DRI-PA
                     DRI Photoacoustic Analyzer (BC)
                                                             Droplet Measurement Technologies, Inc. (Boulder, CO)
    MAAP
                     Multi-Angle Absorption Photometer, Model 5012 (BC)
                                                             Thermo Scientific Corp. (Franklin, MA)
    PSAP
                     Particle Soot Absorption Photometer (BC)
                                                             Radiance Research Inc. (Seattle, WA)
    Other Carbon
    PAS-PAH
                     Photo-lonization Monitor for PAHs (Model PAS 2000)
                                                             EcoChem Analytics (League City, TX)
    PILS-WSOC
    PILS-WSOC Analyzer, combination of PILS and total organic
    analyzer (TOA)
                                                                              Georgia Institute of Technology
    PARTICLE SIZING INSTRUMENTS FOR MASS AND CHEMICAL SPECIATION
    DRUM-3
    Davis Rotating-Drum Uniform Size-Cut Monitor (0.1-2.5 urn in 3
    stages)
                                                                              University of California-Davis (Davis, CA)
    DRUM-8
    Davis Rotating-Drum Uniform Size-Cut Monitor (0.09- > 5.0 urn in 8   Universi(y Qf Ca|ifornia_Davis
    ELPI
                     Electrical Low Pressure Impactor (0.007-10 urn in 12 stages)
                                                             Dekati (Tampere, Finland)
    LPI
                     Low Pressure Impactor (0.03-10 urn in 13 stages)
                                                             Aerosol Dynamics, Inc.
    MOUDI
                     Micro Orifice Uniform Deposit Impactor
                                                             MSP Corp. (Minneapolis, MN)
     MOUDI-100
                     MOUDI Model 100 (0.18-18 urn in 8 stages)
                                                             MSP Corp.
     MOUDI-110
                     MOUDI Model 110 (0.056-18 urn in 10 stages)
                                                             MSP Corp.
     Nano-MOUDI      Nano MOUDI (°-01 °-°-056 M™ in 3 stages coupled to MOUDI Model  Msp c
    PARTICLE NUMBER / VOLUME INSTRUMENTS
    APS
                     Aerodynamic Particle Sizer
                                                                              TSI Inc.
    APS-3320
                     TSI Model 3320 (0.5-20 urn)
                                                                              TSI Inc.
    December  2009
                                                A-3
    

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      Abbreviation                           Instrument                                  Manufacturer/Research Institute
    APS-3321         TSI Model 3321 (0.5-20 um; replaced TSI Model 3320)             TSI Inc.
    DMA             Differential Mobility Analyzer                                   TSI Inc.
     DMA-3081        TSI Model 3081 (0.01-1 .Oum)                                  TSI Inc.
     DMA-3085        TSI Model 3085 (0.002-0.15 um)                                TSI Inc.
    EEPS            Engine Exhaust Particle Sizer (EEPS 0.056-0.56 um)               TSI Inc.
    FMPS            Fast Mobility Particle Sizer (FMPS 0.056-0.56 um)                 TSI Inc.
    GRIMM-1108      Optical Particle Counter (OPC; 0.3-20 um)                       GRIMM Technologies, Inc. (Douglasville, GA)
    SMPS            Scanning Mobility Particle Sizer                                TSI Inc.
     SMPS-3936      TSI Model 3936L (0.01-1 .Oum)                                 TSI Inc.
     Nano-SMPS-3936 TSI Model 3936N  (0.002-0.15 um)                              TSI Inc.
                     SMPS and Condensation Nucleus Counter (0.005-0.35 or           ^DIMMT  hi-   i
                     0.01 -0.875 um)                                              GRIMM Technologies, Inc.
     SMPS-custom    DMA Model 3071 and CPC Model 3010                          TSI Inc.
    WPS             Wide-Range Particle Spectrometer (0.01-10.0 um)                 MSP Corp.
    SINGLE PARTICLE INSTRUMENTS
    AMS             Aerosol Mass Spectrometer (0.04-2 um)                         Aerodyne Research Inc. (Billerica, MA)
    ATOFMS         Aerosol Time of Flight Mass Spectrometer (0.3-2.5 um)             TSI Inc.
    CNC, CPC        Condensation Nucleus Counters, Condensation Particle Counter     Various vendors
                     One Aree(?OoTl0°S6 SpeCtr°meter C°nSiSting °f tW° SMPS 3nd  Carnegie Mellon University
    
    LIBS             Laser-Induced Breakdown Spectroscopy                         (toKte^QuS^airadt)81'181 "*"'** ^^
    PALMS           Particle Analysis by Laser Mass Spectrometer (0.22-2.5 um)         NOAA (Boulder, CO)
    RSMS-II          Rapid Single Particle Mass Spectrometer -II (0.035-1.1 um)          University of Delaware (Newark, DE)
    RSMS-III         Rapid Single Particle Mass Spectrometer III (0.01-2.0  um)           University of Delaware
    LABORATORY INSTRUMENTS
                     DRI Model 2001 Thermal/Optical  Carbon Analyzer (OC, EC, Eight
    DRI Model 2001    Carbon Fractions with reflectance and transmittance laser           Atmoslytic, Inc. (Calabasas, CA)
                     correction)
    SEM             Scanning Electron Microscopy                                 Various vendors
    3Now with Thermo Scientific, Franklin, MA.
    bEPA-approved speciation sampler used in the Speciation Trends Network (STN).
    cNow commercialized by Applikon Analytical, the Netherlands, and marketed under the name "MARGA" (Monitor for Aerosols and Gases in Ambient Air).
    dNot available.
    
                                                                                                           Source: Chowetal. (2008,156355)
    December 2009                                               A-4
    

    -------
    Table A-2.     Summary of PM2.6 and PMio FRM and FEM samplers.
    Manufacturer'   *™ff   ?ize
                                                          Description
                                                                                    Desi9nation#
                                                                                                         FRN
    BGIInc.
    BGI Inc.
                    PQ-100      PM10  Louvered PM10 inlet; operates at flow rate of 16.7 L/min; 24-h    FRM
                                     - integrated sampler; uses a mass flow meter to adjust to equiva-
                                                                                    RFPS19P8194  Vol. 63, p. 69625,
                                                                                    RFPS-1298-124  12/17/98^
    PQ 200      PM    lent volumetric flow at ambient temperature and pressure.       FRM
                                                                                              1?8i:>n  Vol. 63, p. 31991,
                                                                                    RFPS-0598-120  06/11/98
    December  2009
                                                  A-5
    

    -------
     Manufacturer'
                                                   Description
                                                                             ™J,?r  Designation #
                                                                                                         FRN
    Thermo Scientific,
    Inc.
    Thermo Scientific,
    Inc.
    Thermo Scientific,
    Inc.
    Thermo Scientific,
    Inc.
    URG Corp.
    CAPS
    RAAS 100-
    VSCC
    RAAS 200-
    VSCC
    RAAS 300-
    VSCC
    MASS-100
    PM2.5
    PM2.5
    PM2.5
    PM2.5
    PM2.5
    Model 605 Computer Assisted Particle Sampler (CAPS), 24-h
    integrated. Not available commercially.
    Same as RAAS-100 PM15 sampler but with BGI VSCC, instead
    ofWINS impactor.
    Same as RAAS-200 PM25 sampler but with BGI VSCC instead
    ofWINS impactor.
    Same as RAAS-300 PM15 sampler but with BGI VSCC instead
    ofWINS impactor.
    Model MASS100 PM25 sampler with louvered PM10 inlet
    followed by WINS impactor, operates at 16.7 L/min;24-h
    integrated, volumetric flow measured by dry test meter at pump
    outlet modulates pump speed to maintain flow rate; single
    channel.
    FRM
    FEM (II)
    FEM (II)
    FEM (II)
    FRM
    RFPS-1098-123
    EQPM-0804-153
    EQPM-0804-154
    EQPM-0804-155
    RFPS-0400-135
    Vol. 63, p.
    10/29/98
    Vol. 69, p.
    08/06/04
    Vol. 69, p.
    08/06/04
    Vol. 69, p.
    08/06/04
    Vol. 65, p.
    05/08/00
    8036,
    47924,
    47924,
    47925,
    26603,
                                              Model MASS300 PM25 sampler with louvered PM10 inlet fol-
    URGCorp.         MASS-300    PM15   lowed by WINS impactor, operates at 16.7 L/min; 24-h inte-       FRM
                                              grated, sequential sampler with circular tray holding six filters.
    Tisch Environ-
    mental, Inc.
    TE-6070
    HiVol
    PMn
    Model TE-6070 PM10 High-Volume Sampler, with TE-6001 PM1(
    size selective inlet; 8" x 10" filter holder.
                                                                             FRM
    RFPS 0400 136  Vol. 65, p. 26603,
    Ki-rsuiuu  i jo  05/08/00
    
    RFPS 0202 141  Vol. 67, p. 15566,
    KrHb-U4^-141  04/02/02
                                              Models BAM 1020, GBAM 1020, BAM 1020-1, and GBAM
    Met One            BAM          PM10   1020-1, with BX-802 inlet; glass-fiber filter tape with 1-h filter
                                              change frequency.
                                                                                            FEM
                                                                                        FOPM n?QR 199  Vol. 63, p. 41253,
                                                                                        EQPM-0798-122  08/03/98M
    3 BGI Inc.: BGI Incorporated, Waltham, MA. R&P: Rupprecht & Patashnick Company, Inc., Albany, NY, now Thermo Scientific, Inc., Franklin, MA. Andersen: Graseby Andersen, later Andersen Instruments,
    Inc., Smyrna, GA, now Thermo Scientific, Inc., Franklin, MA. Thermo Environmental Instruments, Inc., now Thermo Scientific, Inc., Franklin, MA. URG Corp.: URG Corporation, Chapel Hill, NC. Tisch
    Environmental, Inc., Cleves, OH. Met One Instruments, Inc., Grants Pass, OR
    b The efficiency of an inlet (Watson et al., 1983, 045084) is determined by its 50% cut-point (d50, the diameter at which half of the particles penetrate through the inlet, while the other half is retained by the
    inlet, while the other half is retained by the inlet) and the geometric standard deviation (GSD, which is an indicator of the sharpness of the separation, and is derived by the square root of the ratio of particle
    diameters at penetrations of 16% andc 84%, [d16/dB/5).
    c FRM: Federal Reference Method; FEM: Federal Equivalent Method. Roman numeral within parenthesis indicates FEM class.
    d Particle separation in WINS is achieved by means of a single-jet round nozzle with flow directed into an impaction reservoir. The impaction surface consists of a GelmanTypeA/E glass-fiber filter immersed
    in 1  mL of Dow Corning (Midland, Ml) 704 diffusion pump oil housed in a reservoir.
    Note: The geometric standard deviation (GSD, which is an indicator of the sharpness of the separation, and is derived by the square root of the ratio of particle diameters at penetrations of 16% and 84%,
    [d16/d84]0.5).
    
    
                                                                                                                                Source: Chowetal.  (2008,156355)
    December 2009
                                                            A-6
    

    -------
    Table A-3.
    Observable
    PM2.5 mass
    Elements
    Nitrate
    Sulfate
    Ammonium
    OC, EC.TC
    Total mass of
    WSOC
    Elements in
    water soluble
    matter: C, H, N,
    andS
    Dissolved
    organic
    nitrogen
    Measurement and analytical specifications for filter analysis of mass, elements, ions,
    and carbon.
    Analytical
    Accuracy3
    ± 5% 4
    ± 2-5% 4
    1 6% with spiked
    concentrations on
    Teflon4
    and 1 1-1 4% on
    nylon filters! 3
    ± 5% 4
    ± 5% 4
    1 5% for TC and
    OC. No standard
    exists to determine
    EC accuracy
    DPI Model 2001
    Carbon
    Analyzer: + 5%
    TOA: ± 3-7% 24'25
    C:1.5%;
    H:3%;
    N:3%;
    S:5%30
    N/A
    Preclslonb
    ±10%4
    ±10%4
    ±5 to 10% on repli-
    cate analysis 4l13'
    co-located
    precision 1 5-7%14'16
    ±6to10%4'14'15
    ±10%4
    OC: ± 20%
    EC: ± 20%
    TC: ± 10% 4
    DPI Model 2001
    Carbon
    Analyzer: + 10%
    Sunset Carbon
    Analyzer: ± 3%26
    TOA:±5-10%27
    ±2%30
    ± 5-30%31
    Minimum
    Detectable Limit
    (MDL)
    0.04 ug/m3 c to
    ~1ug/m3d5<6
    XRF: 0.4-30 ng/m3 g
    8PIXE:6-360ng/m3
    d9ICP/MS: 0.004-25
    ng/m3 1° 0.05-11. 7
    ng/m39'11 AAS: 0.02-
    7.15 ng/m312
    0.06 ug/m3 e to
    0.2 ug/m3 d1'6'17
    0.06ug/m3;to
    0.2ug/m3d1'6'13
    0.06 ug/m3e to
    0. 07 ug/m3 d1'6
    OC:0.1 ug/m3 f to
    0.8 ug/m3 d
    EC : 0.03 ug/m3 d to
    0.1 ug/m3'
    TC:0.8ug/m3d1'6
    DRI Model 2001
    Carbon Analyzer:
    0.1-0.23 ugC/m323
    Sunset Carbon
    Analyzer: 0.05-
    0.22ugC/m326'28
    Elemental High TOC
    N:0.05ugC/m329
    TOA:0.12 |jg
    C/m326
    C: 0.3 ug/m3
    H:0.09 ug/m3
    N: 0.03 ug/m3
    S: 0.10 ug/m330
    0.001 ug N/m3 while
    inorganic nitrogen is
    low;>0.071ugN/m3
    while inorganic
    nitrogen is high31
    Interferences
    Electrostatic charges need to
    be neutralized before
    measurement; positive (e.g.,
    OC adsorption) and negative
    artifacts (e.g., nitrate
    volatilization)
    Volatile compounds may evap-
    orate from filters due to vac-
    uum in XRF and PIXE.
    Potential contamination during
    extraction and incomplete
    extraction efficiency for ICP-
    MS and AAS. Matrix
    interference and peak overlap
    may occur on heavily loaded
    samples.
    Subject to volatilization from
    Teflon or quartz-fiber filters
    N/A
    Subject to volatilization from
    Teflon or quartz-fiber filters
    Subject to adsorption (positive
    artifact) and volatilization
    (negative artifact) of organic
    gases to and from quartz-fiber
    • filters
    Extraction efficiency and
    volume reduction steps
    Contamination during sample
    drying step
    Concentration of inorganic
    nitrogen
    Comparability
    Within 20% 4
    10 to 30% depending
    on species 4
    Within 35% and
    probably greater4
    Typically within 10%;
    MOUDIs13to20%
    lower than speciation
    samplers4'1*9
    Within 30% 4
    OC: Within 20 to
    50%
    EC: Within 20 to
    200%
    TC: Within 20% 4'17'22
    Within! 7% 26
    N/A
    Good correlation
    between UV and
    persulfate oxidation
    methods (R2 = 0.87)
    Data
    Completeness
    90 to 1 00% h6'7
    90to100%h6J
    85 to 1 00% "
    l^00%
    86 to 1 00% 6'7
    86 to 1 00% 6'7
    N/A
    N/A
    N/A
    December 2009
    A-7
    

    -------
    
    
    
    
    
    
    and polyether
    
    
    Mono- and
    Di-carboxylic N/A
    acids
    
    
    Amino acids N/A
    
    
    Mass of humic-
    like substances N/A
    (HULIS)
    
    ^!VS Precisionb
    
    
    GC/MS: 1 23% 33'34
    Typically + 20%,
    3. + 48o/32 ranged from + 10
    ='±4-°/0 to + 30%'32'3"6'37'38
    HPLC/MS:
    ± 5-26%39
    
    GC/MS: ±5-11% on
    3 rerjlicates, + 8 % in
    avg
    IC:±10-15%45
    
    
    ± 9% 48
    
    
    
    N/A
    
    Minimum
    Detectable Limit
    (MDL)
    GC/MS:
    Levoo,lucosan:10
    
    2. 08 ng/m3 j31
    0.01 -0.03 ng/m333'41
    HPLC/MS: 9-648
    pg/m339
    
    GC/MS: 0.04-1 .12
    ng/m346
    1C: 0.01 -0.1 2 ng/m3
    
    
    1.65-23.6
    pg/m3k48
    
    
    
    0.083 ng/m3149
    
    
    Interferences
    
    
    GCMS: Extraction recovery
    interfered by sample matrix
    Derivatization efficiency
    IC/PAD: Overlapping peaks in
    chromatogram
    GC/MS: Extraction recovery
    interfered by sample matrix
    Derivatization efficiency
    1C: Overlapping peaks in
    chromatogram
    Derivatization efficiency
    Stability of derivatives
    Overlapping peaks in
    chromatogram
    
    Separation efficiency
    
    
    Comparability
    
    
    IC/PAD: Good
    correlation
    (R2 = 0.97) with
    HPLC/MS; and
    (R2 = 0.89) with
    GC/MS Method 42
    
    GC/MS: Within 50%
    for less volatile
    compounds 46
    
    
    N/A
    
    
    
    N/A
    
    
    r it
    omp
    
    
    
    N/A
    
    
    N/A
    
    
    N/A
    
    
    
    N/A
    
    3 Accuracy is the ability of analytical methods to quantify the observable of a standard reference material correctly; it does not refer to measurement accuracy if no standards available.50
    b Refers to precision of co-located measurements, unless specified otherwise.
    c Based on 1 ug/filter limit of detection for 24-h samples, assuming a flow rate of 16.7 L/min
    d Based on field blanks collected with FRM samplers; ug/filter converted to ug/m3 basis assuming a flow rate of 16.7 L/min for 24-h
    s Based on '/? of a 47-mm filter extracted in 15 mLdeionized-distilled water (DDW) for 24-h samples, assuming a flow rate of 16.7 L/min
    f Based on 0.2 ug/cm2 detection limit and 13.8 cm2 deposit area for a 47-mm filter, assuming a flow rate of 16.7 L/min for 24-h
    9 Based on 24-h samples at a flow rate of 16.7 L/min and analyzed by XRF
    h Except for samples from one FRM sampler at Atlanta Supersite, for which data recovery was 50%7; reason not reported.
     Reported as uncertainty in literature
    J Based on 24-h samples at a flow rate of 16.7 L/min
    k Based on 13.8 cm2 deposit area for a 47-mm filter and extracted into a final volume of 200 uL, assuming a flow rate of 16.7 L/min for 24-h and molecular weight of amino acid = 150
     Based on 13.8 cm2 deposit area for a 47-mm  filter and extracted into a final volume of 200 uL, assuming a flow rate of 16.7 L/min for 24-h
    N/A: Not available
    
    
    'Chow (1995, 0770121:2Watson and Chow (2001,1571231:3 Watson et al. (1983, 0450841:4Fehsenfeld et al. (2004,1573601:5Solomon et al. (2001,1571931: BWatson et al. (2005,1571241:7Mikel (2001,
    1567621: "Watson et al. (1999, 0209491:8Solomon and Sioutas (2006,1569951:10Graney et al. (2004, 0537561: "lanaka et al. (1998,1570411:12Pancras et al. (2005, 0981201: "John et al. (1988, 0459031:
    "Hering and Cass (1999, 084958): 15Fitz et al. (1989, 077387): "Hering et al. (1988, 036012): "Solomon et al. (2003,156994): "tabada et al. (2004,148859): "Fine et al. (2003,155775): 20Hogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 0991601:22Watson et al. (2005,1571251:23Ho et al. (2006,1565521:24Decesari et al. (2005,1445361:25  Mayol-Bracero et al. (2002, 0450101:2BYang et al. (2003,
    1561671:27 Tursic et al. (2006,1570631:2BMader et al.(2004,1567241:28Xiao  and Liu (2004, 0568011:30Kiss et al. (2002,1566461:31Cornell and  Jickells (1999,1563671:32 Zheng et al. (2002, 0261001:
    33Fraser et al. (2002,140741): x Fraser et al. (2003, 042231) 35Schauer er al. (2000, 012225): 3BFine et al. (2004,141283): 37Yue  et al. (2004,157169): 3BRinehart et al. (2006,115184): 38Wan and Yu (2006,
    1571041:40Poore (2000, 0128391:41Fraser et al. (2003, 0402661:42Engling et  al. (2006,1564221:43Yu et al. (2005,1571671:44Tran et al. (2000, 0130251:45Yao et al. (2004,1022131:4BLi and Yu (2005,
    1566921: "Henning et al. (2003,1565391: 
    -------
    Table A-4. Measurement and analytical specifications for filter analysis of organic species.
    Organic Analytical Accuracy
    
    TD Solvent
    Extraction
    PAHs ±2.8-24.1%51 Z-score
    „ values 0 to -
    ±4.4-29.4% ig56
    13.8-26.5%53 +4_8%32
    ±0.5-12.9%54 ±6.5.22%57
    0.05-4.83%55
    
    
    
    
    
    
    
    
    n-Alkanes N/A ± 4-8%32
    
    
    
    Hopanes N/A N/A
    
    
    
    Steranes N/A N/A
    
    
    Organic acids N/A +4-8%32
    (including n-
    alkanoic
    acids, n-
    alkenoic
    acids, alkane
    dicarboxylic
    acids,
    aromatic
    carboxylic
    acids, resin
    acids)
    
    
    
    
    
    
    
    
    
    
    
    Precision
    
    TD
    
    Avg ± 3.2%,
    ranged
    from ±0.05 to
    ±11.5%55
    
    
    
    
    
    
    
    
    Avg ± 3.2%,
    ranged
    from ± 0.05
    to±11.5%55
    
    Avg ±3.2%,
    ranged
    from + 0.05
    to + 11.5%55
    
    
    Avg + 3.2%,
    ranged
    from + 0.05
    to + 11.5%55
    ±10 55
    to + 29%55
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Solvent
    Extraction
    Avg ±8%,
    ranged from
    ±3.8
    to±15%56
    ±23%56Avg
    ±2.6%,
    ranged
    from ±0.6 to
    ±9.5%57
    typically
    
    ± 20%,
    ranged
    from± 10 to
    ± 30%c 32'35"37
    ±23%56
    Typically ± 20
    %, from ±10
    to ± 30%c 32'35"
    37
    + 23%56
    Typically + 20
    %, from ±10
    t3o + 30%c32'35"
    
    N/A
    
    
    + 24%41
    + 23 %56
    Typically + 20
    %, from + 10
    * _L onn/ c 32,35-
    to + 30%
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    MDL
    
    TD
    
    0.016-0.48
    ng/m3358
    0.030-0.45
    ng/m3355
    
    
    
    
    
    
    
    
    0.081-0.86
    ng/m3358
    ng^'M7
    
    0.030-0.14
    ng/m3355
    
    
    
    0.018-0.063
    ng/m3355
    
    
    Mono-
    carboxylic
    acids (C8,
    C12, and
    C16):
    0.79, 2.0, and
    3. 2 ng/m3354
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Solvent
    Extraction
    0.83-1.66
    ng/m3b38
    0.033-3.85
    ng/m3b56
    0.01-0.03
    ng/m333'34'37
    0.76-276
    Pg/m3b57
    
    
    
    
    
    
    
    0.01-0.03
    ng/m333'34'37
    
    
    0.83-1 .66
    ng/m3b38
    °-01-3033°431
    ng/m333'41
    0.01 ng/m337
    0.83-1 .66
    ng/m3b60
    
    
    0.01-0.03
    ng/m333'41
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Interferences
    
    TD
    
    Fragmentatio
    n of labile
    com-
    pounds
    
    
    
    
    
    
    
    
    Same as
    PAHs
    
    
    Same as
    PAHs
    
    
    
    Same as
    PAHs
    
    
    Fragmentatio
    n of labile
    compounds.
    Loss of polar
    species due
    to absorption
    onto the
    surface of the
    injector.
    Improper sta-
    tionary phase
    column used
    during TD
    analysis.
    
    Incomplete
    thermal
    desorption of
    analytes
    because of
    strong affinity
    with filter
    matrix.
    
    Solvent
    Extraction
    Possible
    contaminants
    from solvents
    and compli-
    cated extrac-
    tion
    procedures.
    Loss of
    volatile
    compounds
    during the ex-
    traction and
    pretreatment
    steps.
    Possible
    carryover
    from injection
    port.
    Same as
    PAHs
    
    
    Same as
    PAHs
    
    
    
    Same as
    PAHs
    
    
    Possible
    contaminants
    from solvents
    and com-
    plicated
    extraction
    procedures.
    Loss of
    volatile
    compounds
    during the ex-
    traction and
    pretreatment
    steps.
    
    Possible
    carryover
    from injection
    port .
    
    Low
    derivatization
    efficiency .
    
    Comparabil
    ity
    
    
    R2s for solvent
    extraction
    were 0.95 58,
    0.9755. and
    0.98 59
    
    
    
    
    
    
    
    
    R2s for solvent
    extraction are
    0.94 58 and
    0.98 55'59
    
    R2s for solvent
    extraction are
    0.99 55 and
    0.998 59
    
    
    R2s for
    solvent
    extraction are
    0.97 55 and
    0.998 59
    Correlation
    with solvent
    extraction
    method
    R2 = 0.731 59
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    December 2009
    A-9
    

    -------
    Analytical Accuracy
    Polyols and N/A ± 4-8%32
    sugars,
    including gua-
    iacol and sub-
    stituted
    guaiacols, sy-
    ringol and
    substituted
    syringols,
    an hydro-
    sugars
    Precision
    N/A ± 23%56 N/A
    Typically ± 20
    %, from ±10
    t3o±30%c32'35"
    
    
    
    
    
    MDL Interferences
    Levoglucosa: Same as Same as N/A
    10ng/m361 organic acids organic acids
    2.08ng/m3b38
    0.01-0.03
    nn/m333'41
    
    
    
    
    
    3 Assumes 2.9 cm  filter used in analysis from a deposit area of 13.8 cm , and sample collection at a flow rate of 16.7 L/min for 24-h
    bAssumes sample collection at a flow rate of 16.7 L/min for 24-h.
    c Reported as uncertainty in literature.
    dAssumes a final extract volume of 1 mL and sample collection at a flow rate of 16.7 L/min for 24-h.
    N/A: Not available
    
    
    'Chow (1995, 0770121:2Watson and Chow (2001,1571231:3 Watson et al. (1983, 0450841:4Fehsenfeld et al. (2004,1573601:5Solomon et al. (2001,1571931: BWatson et al. (2005,1571241:7Mikel (2001,
    156762): "Watson et al. (1999, 020949): 9Solomon and Sioutas (2006,156995): '"Graney et al. (2004, 053756): "Tanaka et al. (1998,157041): 12Pancras et al. (2005, 098120): "John et al. (1988, 045903):
    "Hering and Cass (1999, 0849581:15Fitz et al. (1989, 0773871:1BHering et al. (1988, 0360121: "Solomon et al. (2003,1569941:1BCabada et al. (2004,1488591: "Fine et al. (2003,1557751:20Hogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 0991601:22Watson et al. (2005,1571251:23Ho et al. (2006,1565521:24Decesari et al. (2005,1445361:25 Mayol-Bracero et al. (2002, 0450101:2BYang et al. (2003,
    156167): 27Tursic et al. (2006,157063): 2BMader et al.(2004,156724): 29Xiao and Liu (2004, 056801): 30Kiss et al. (2002,156646): 31Cornell and Jickells (1999,156367):32 Zheng et al. (2002, 026100):
    33Fraser et al. (2002,140741): x Fraser et al. (2003, 042231135Schauer er al. (2000, 0122251:3BFine et al. (2004,1412831:37Yue et al. (2004,1571691:3BRinehart et al. (2006,1151841:39Wan and Yu (2006,
    1571041:40Poore (2000,  0128391:41Fraser et al. (2003, 0402661:42Engling et al. (2006,1564221:43Yu et al. (2005,1571671: ""Iran et al. (2000, 0130251:45Yao et al. (2004,1022131:4BLi and Yu (2005,
    156692): "Henning et al. (2003,156539): 
    -------
    Table A-5.     Measurement and analytical specifications for continuous mass and mass surrogate
                  instruments.
        Instrument and      Averaging
    Measurement Principle     Time
    Analytical   Precisionb
    Accuracy3
    MDL      Interferences Comparability     Data
                                    Completeness
    INERTIA INSTRUMENTS
    TEOM Air is drawn through a 10min-24h ±0.75%c
    size-selective inlet onto the
    filter mounted on an
    oscillating hollow tube. The
    oscillation frequency
    changes with mass loading
    on the filter, which is used to
    calculate mass concentration
    by calibrating measured
    frequency with standards.
    FDMS TEOM. A self-refer- 1 h-24 h ± 0.75%c
    encing TEOM with a filter at
    4 °C that accounts for
    volatile species. It is
    equipped with a diffusion
    Nafion dryer to remove
    particle-bound water. The
    Teflon (PTFE)-coated boro-
    silicate glass-fiber filter that
    is maintained at 4 °C re-
    moves particles during the
    reference flow cycle. The
    flow alternates between a
    base and reference flow
    every 6 min. If a negative
    mass is measured during the
    reference flow, due to loss of
    volatiles from the filter, it is
    added to the mass made
    during the prior particle-
    laden samples to obtain total
    PM2.5 concentration.
    Differential Tapered Element 1 h-24 h ±0.75%c
    Oscillating Microbalance (D-
    TEOM)
    Similar to FDMS, but an
    electrostatic precipitator is
    used in place of the glass-
    fiber filter to remove particles
    during the 6 min reference
    flow cycle.
    RAMS.ATEOMwitha 10min-24h N/A
    cyclone inlet, diffusion
    denuders, and Nafion dryer.
    Particles are collected on a
    "sandwich" filter (Teflon fol-
    lowed by carbon-
    impregnated glass-fiber
    filter) on the tapered
    oscillating element. The
    various denuders remove
    gas phase organic com-
    pounds, nitric acid, sulfur
    dioxide, nitrogen dioxide,
    ammonia, and ozone, which
    could otherwise be adsorbed
    by the TEOM filter.
    ± 5 ug/m for 0.01 ug, which is
    10-minavgc,d 0.06 ug/m for 1-h
    avgc
    ± 1 .5 ug/m for
    1-havg^d
    <10%65 0.01 ug, which is
    0.06 ug/m3
    for1-havgc
    <1()%e 65,69,70 Q.01 Ug, Or
    0.06 ug/m3 for 1-h
    avgc
    <10%f71 ± 1 to 2 ug/m3 for
    30-min avg 72
    Loses semi-
    volatile species
    at both 30°C
    and 50°C.
    SESTEOM,
    while less
    sensitive to
    relative
    humidity, does
    not completely
    eliminate loss
    of semi-volatile
    species
    N/A
    N/A
    N/A
    Underestimated 99%6587-92%6
    FRM mass by
    20 to 35% 62-<4
    9 to 30% higher 95-99%65'68
    than FRM mass 67
    Within 10% of 57-65%
    mass by D-
    TEOM, PC-
    BOSS, RAMS
    and BAM 66'67
    Within 10% of 86%65
    FDMS-TEOM
    10 to 20% N/A
    higher than avg
    72 FRM mass
    December 2009
                     A-11
    

    -------
        Instrument and       Averaging    Analytical    Precisionb
     Measurement Principle     Time      Accuracy3
                        MDL       Interferences Comparability      Data
                                                               Completeness
    PRESSURE DROP INSTRUMENT
    Continuous Ambient Mass 1 h-24 h N/A
    Monitor (CAMM)
    Air is drawn through a Tef-
    lon-membrane filter tape and
    the pressure drop across the
    filter is monitored
    continuously. The proportion
    of pressure drop to aerosol
    loading is related to the PM
    concentration. The filter tape
    advances every 30-60 min to
    minimize volatilization and
    adsorption artifacts during
    sampling.
    28.1% for 1-h <5ug/m3for1h
    avg avg
    
    15.9% for 24-h
    avg
    (-3.5 ug/m )
    
    
    
    
    
    
    
    
    Needs effective
    sealing for
    good
    performance;
    even slight
    leaks may
    result in highly
    variable
    baseline.
    Probably less
    sensitive than
    DTEOM or
    RAMS. 75'77
    
    Varied perfor- N/A
    ma nee: within
    2%ofSES-
    TEOM and FRM
    at Houston, TX,
    while not
    correlated with
    D-TEOM or
    FRM at
    Rubidoux,
    CA.76'77
    
    
    
    B-ATTENUATION INSTRUMENT
    B Attenuation Monitor (BAM) 1 h-24 h
    B rays electrons are passed
    through a quartz-fiber filter
    tape on which particles are
    collected. The loss of
    electrons (B attenuation)
    caused by the particle
    loading on the filter is
    converted to mass
    concentration, after subtrac-
    tion of blank filter
    attenuation.
    
    
    ± 3 ug for ±2 ug/m3 c'h
    24-h avg
    concentrations
    < 100 ug/m3
    and 2% for
    100 to
    1 ,000 ug/m3
    
    ±8 ug for 1-h
    concentrations
    < 1 00 ug/m3
    and 8% for
    100 to
    1000 ug/m3
    5 ug/m3 for 1-h avg1 Water Up to 30% 93-99%6'65'67
    absorption by higher than FRM
    particles may mass and within
    result in higher 2%ofFDMS
    mass measure- TEOM 63'67
    ments; maybe
    important at RH
    >85%
    
    
    
    
    
    
    LIGHT-SCATTERING INSTRUMENT
    Nephelometers (including    5 min-24 h
    DustTrak)
    
    A light source illuminates the
    sample air and the scattered
    light is detected at an angle
    (usually 90°) relative to the
    source. The signal is related
    to the concentration of the
    particles giving an estimate
    of the particle light-scattering
    coefficient. Zero air calibra-
    tions can be performed using
    particle-free air.
                                          N/A
    Nephelometers:
    <5%forTSI
    andNGNi
    nephelo meters
    
    
    DustTrak:
    Greater of 0.1%
    oM ug/m3c'h
    Nephelo meter:
    < 1.5 Mm'1
    Conversion fac-
    tor to calculate
    r,  „ ,    .   ,3 massconcen-
    DustTrak: ± 1 ug/m  (ration from
    for 24-h avg1       bscat may vary
                     depending on
                     particle size,
                     shape and
                     composition.
    
                     Light scattering
                     by DustTrak
                     proportional to
                     dp 6 for dp
                     < 0.25 urn 79
    Typically good
    correlation with
    SES-TEOM and
    D-TEOM (R2
    >0.80).
    
    Comparability
    depends on
    conversion
    factor used.
    >80-98% for
    NGN2, RR-M903
    and GreenTek
    Nephelometers 6
    
    >80% for
    DustTrak6
    98% for GRIMM
    optical particle
    counter65
    December  2009
             A-12
    

    -------
          Instrument and         Averaging     Analytical      Precisionb
     Measurement Principle        Time         Accuracy3
                                                                MDL          Interferences  Comparability        Data
                                                                                                                        Completeness
    3 Accuracy is the ability of analytical methods to quantify the observable of a standard reference material correctly; does not refer to measurement accuracy, since no standards available.
    b Refers to precision of co-located measurements, unless specified otherwise.
    c Manufacturer-specified measurement parameter.
    d Details not available on how the precision was obtained and whether it refers to co-located precision.
    e Includes a combination of estimates: based on co-located precision and based on regression slopes.
    f Co-located precision with respect to PC-BOSS reconstructed PM2 5 mass.
    9 Using glass-fiber "sandwich" filter.
    h Specified as "resolution" by the manufacturer.
    'Co-located precision estimate based on regression slope for NGN nephelometer (slope = 1.01, intercept = -1.64 ug/m3, R2 = 0.99).
    J Specified as "Zero stability" by the manufacturer.
    N/A: Not available.
    1Chow (1995, 0770121: 2Watson and Chow (2001 , 157123): 3 Watson et al. (1983, 0450841: Vehsenfeld et al. (2004, 1573601: 5Solomon et al. (2001 , 1571931: "Watson et al. (2005, 1571241: 7Mikel (2001 ,
    1567621: BWatson et al. (1999, 0209491: 'Solomon and Sioutas (2006, 1569951: 10Graney et al. (2004, 0537561: "lanaka et al. (1998, 1570411: 12Pancras et al. (2005, 0981201: "John et al. (1988, 0459031:
    "Hering and Cass (1999, 0849581: 15Fitz et al. (1989, 0773871: "Hering et al. (1988, 0360121: "Solomon et al. (2003, 156994): 1BCabada et al. (2004, 148859): "Fine et al. (2003, 1557751: 20Hogrefe et al.
    (2004, 0990031: 21Drewnick et al. (2003, 0991601: 22Watson et al. (2005, 1571251: 23Ho et al. (2006, 1565521: 2
    -------
    Table A-6.     Measurement and analytical specifications for continuous elements.
                                                          Precision
             MDL
                                                                                                                                 Data
    Interferences   Comparability  Comp|eteness
    Semi-continuous 15-30 min ±10%bforMn, 20-43%c80
    Elements in Aerosol Fe, Ni, Cu, Zn, Se,
    System (SEAS) Cd, and Sb
    
    Particles are collected at + 20%b for Cr, As,
    30-min interval for and Pb 80
    subsequent laboratory
    atomic absorption
    analysis for elements.
    Aerosol collection is
    through condensational
    growth by direct steam
    injection. The grown
    particles are separated
    from the airstream using
    virtual impactor. The
    droplets accumulate in a
    slurry that is pumped to
    a separate sample vial
    for each time period.
    Laser-Induced A few N/A N/A
    Breakdown seconds
    Spectroscopy (LIBS)
    
    Used for in-situ single
    particle analysis. A high-
    power pulsed laser is
    projected into particles
    producing high-
    temperature plasma.
    Photons emission from
    relaxing atoms in the
    excited states provides
    characteristics of
    individual elements.
    Al:440pg Spectral N/A N/A
    Cr: 6.7 pg interferences limit
    Mn:9.9pg the number of
    Fe: 85 pg elements detected
    Ni: 42 pg simultaneously
    Cu: 26 pg
    Zn: 43 pg
    As: 27 pg
    Se: 33 pg
    Cd: 3.2 pg
    SbieOpg,,
    Pb: 31 pg50
    
    
    
    
    
    
    
    Na:143fg N/A N/A N/A
    Mg:53fg
    Al: 184 fg
    Ca: 50 fg
    Cr: 166fg
    Mn: 176 fg
    CuMSfg91
    
    
    
    
    
    
    
    
    3 Accuracy is the ability of analytical methods to quantify the observable of a standard reference material correctly; does not refer to measurement accuracy, since no standards are available.
    b Based on analysis of standard reference material (SRM) 1643d from National Institute of Standards and Technology (NIST).
    c Based on error propagation.
    N/A: Not available
     (Kidwell and Ondov, 2004,155898)'  (Lithgowet al., 2004,
                                                                                                                Source: Chowetal. (2008,1563551
    December 2009
    A-14
    

    -------
    Table A-7.      Measurement and analytical specifications for continuous N03-.
      Instrument and Measurement   Averaging  Analytical D    •  •
                 Principle                 Time    Accuracy3 Precision
                                         MDL
                           Interferences   Comparability
                        Data
                    Completion
    FLASH VOLATIZATION INSTRUMENTS
    Aerosol Dynamics Inc. continuous nitrate
    analyzer (ADIN)
    Particle collection by humidification and lnmin M/A
    impaction followed by flash volatilization ' u mln N/rt
    and detection of the evolved gases in a
    chemiluminescent NOX analyzer.
    
    N/A 0.1 ug/m3 for
    N/A 10-minavg82
    
    Within ?n% nf
    filter and
    N/A continuous N03". 93%7
    See Weber et al.
    82 for details
    
    Rupprecht and Patashnick continuous
    nitrate analyzer (R&P-8400N)
    Particle collection by impaction followed
    by flash volatilization and detection of
    the evolved gases in a
    chemiluminescent NOX analyzer. A
    carbon honeycomb denuder, installed at
    the inlet to the Nafion humidifier
    removes nitric acid and ammonia vapor.
     10 min
                  N/A
                           Conversion and
                            volatilization
                          efficiency appears
                            to depend on
                              ambient
            0.24 ug/m to  composition; extent
            n/c'"•'•"'"   of underestimation
                           increases with
                               higher
                         concentrations.  '
                                        0.17 to
                                     0.3 ug/m3 for
                                     24-h avg 83'84
                                     0.45 ug/m for
                                      10-minavg
                                                                     20 to 45% lower
                                                                                    >80->94%6
                                                                                          85
    DENUDER-DIFFERENCE INSTRUMENT
    Atmospheric Research and Analysis
    nitrate analyzer (ARAN)
    Sampled air passes through a 350°C
    molybdenum (Mo) mesh that converts
    particulate nitrate into NO. A pre-split
    stream with a Teflon filter installed
    upstream of an identical converter
    (i.e., particle-free air) is used as a
    reference. NO in both streams is
    quantified by chemiluminescence and
    their difference determines the
    particulate nitrate concentration. The
    instrument inlet contains a potassium
    iodide- coated denuder to remove HN03
    and N02.
      30s
                  N/A
                             N/A
            0.5 ug/m3 for
             30-s avg 82
                                                         N/A
     Within 30% of
       filter and
    continuous N03~.
    See Weber et al.
      82 for details.
                                                                                        76%7
    SAMPLE DISSOLUTION FOLLOWED BY 1C ANALYSIS INSTRUMENTS
    Energy Research Center of the
    Netherlands (ECN) IC-based ion
    analyzer
    Collects particles into water drops using
    a steam jet aerosol collector, via
    cyclone. The combined flow from
    collected droplets containing dissolved
    aerosol components and wall steam
    condensate is directed to an anion 1C for
    analysis of nitrate. Interfering gases are
    pre-removed by a rotating wet annular
    denuder system.
       1h
                  N/A
    N/A      0.1 ug/m3
                                                         N/A
     Within 30% of
       filter and
    continuous N03~.
    See Weber et al.
      82 for details.
                                                                                        100%7
    Texas Tech University (TT) ion analyzer
    Particles in the sample stream are
    processed through a cyclone and a
    parallel plate wet denuder, then collected
    alternatively on one of two 2.5 cm pre-
    washed glass fiber filters for a period of
    15 min. The particles on the freshly
    sampled filter are automatically
    extracted for 6.5 min with water and
    analyzed for nitrate by 1C.
    15-30 min
                  N/A
                             N/A
                                     0.010 ug/m
                                                         N/A
                                            Within 30% of
                                              filter and
                                           continuous N03~.
                                           See Weber et al.
                                             82 for details.
                                                                                        97%7
    Particle into Liquid Sampler-Ion
    Chromatography (PILS-IC)
    Ambient particles are mixed with
    saturated water vapor to produce
    droplets collected by impaction. The
    resulting liquid stream is analyzed with
    an 1C to quantify aerosol ionic
    components.
       1 h
                  N/A
                                              l/nr
                                            Within110% of
                          Consistent water    nylon-filter N03
                          quality is essential   and 37% higher
                          for good precision,  than R&P-8400N
                                                                                      65-70%"
    December 2009
                              A-15
    

    -------
       Instrument and Measurement     Averaging  Analytical   D    •  •
                    Principle                    Time     Accuracy3   Precision
                                                 MDL
                                              Interferences    Comparability
                                                                             Data
                                                                         Completion
    Dionex-IC
    The gas-denuded air stream enters the
    annular channel of a concentric nozzle,
    where deionized water generates a
    spray that entrains the particles. The
    flow is then drawn through a 0.5 urn pore
    size PTFE filter. The remaining solution
    is aspirated by a peristaltic pump and
    sent to 1C for ion analysis.
       1h
                     N/A
                                 14%"
                                                 N/A
                                             Consistent water
                                             quality is essential
                                             for good precision.
                                                      Bias of < 10%
                                                      relative to filter
                                                          NOs'65
                                                                                                             N/A
    Ambient Ion Monitor (AIM; Model 9000)
    Air is drawn through a size-selective inlet
    into a liquid diffusion denuder where
    interfering gases are removed. The
    stream enters a supersaturation
    chamber where the resulting droplets
    are collected through impaction. The col-
    lected particles and a fraction of the
    condensed water are accumulated  until
    the particles can be injected into 1C for
    hourly analysis.
       1h
                     N/A
                                  N/A
                            0.1 ug/m3 for
                               1-havge
                                                                     N/A
                                                                                          N/A
                                                                                                             N/A
    PARTICLE MASS SPECTROMETER INSTRUMENT
    Aerosol Mass Spectrometer (AMS)
    Air stream is drawn through an
    aerodynamic lens and focused into a
    beam in a vacuum chamber. This
    aerosol beam is chopped by a
    mechanical  chopper and the flight time
    of the particles through a particle-sizing
    chamber is determined by the time-
    resolved mass spectrometer
    measurement. The  particle impacts onto
    a 600 °C heated plate where  it
    decomposes and is analyzed by a
    quadruple mass spectrometer. The
    nitrate ion, along with other ions, is
    detected by the mass spectrometer.
     A few
    seconds
    N/A
    N/A     0.03 ug/m3
         Subject to
     interferences from
     fragments of other
     species with mass
      to charge ratio in
     the same range as
    fragments of nitrate.
      Highly refractory
      materials are not
         detected.
      Within 10% of
     nylon-filter N03",
    and within 15% of
    PILS-IC and 30%
    of R&P8400N  20
                                                                                         94-98%20
    3 Accuracy is the ability of analytical methods to quantify the observable of a standard reference material correctly; does not refer to measurement accuracy, since no standards are available.
    b Overall uncertainty estimated by error propagation.
    c Uncertainty estimated from uncertainties in flow rates and calibrations; does not refer to co-located precision.
    a Co-located precision with respect to PC-BOSS PM25 total particulate N03 (the sum of the denuded front filter [non-volatilized N03-] and HN03-absorbing backup filter [volatilized N03]).
    s Manufacturer specified measurement parameter
    N/A: Not available.
    
    
    
    1Chow (1995, 077012): 2Watson and Chow (2001,1571231:3 Watson et al. (1983, 045084): 4Fehsenfeld et al. (2004,1573601:5Solomon et al. (2001,1571931: BWatson et al. (2005,1571241:7Mikel (2001,
    156762): "Watson et al. (1999, 020949): 'Solomon and Sioutas (2006,156995): 10Graney et al. (2004, 053756): "Tanaka et al. (1998,157041): 12Pancras et al. (2005, 098120): "John et al. (1988, 045903):
    "Hering and Cass (1999, 0849581:15Fitz et al. (1989, 0773871:1BHering et al. (1988, 0360121: "Solomon et al. (2003,1569941:1BCabada et al. (2004,1488591: "Fine et al. (2003,1557751:2DHogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 0991601:22Watson et al. (2005,1571251:23Ho et al. (2006,1565521:24Decesari et al. (2005,1445361:25 Mayol-Bracero et al. (2002, 0450101:26Yang et al. (2003,
    156167): 27Tursic et al. (2006,157063): 2BMader et al.(2004,156724):  28Xiao and Liu (2004, 056801): 30Kiss et al. (2002,156646): 31Cornell and Jickells (1999,156367):32 Zheng et al. (2002, 026100):
    33Fraser et al. (2002,1407411: x Fraser et al. (2003, 042231135Schauer er al. (2000, 0122251:3BFine et al. (2004,1412831:37Yue et al. (2004,1571691:3BRinehart et al. (2006,1151841:39Wan and Yu (2006,
    1571041: "Poore (2000, 0128391:41Fraser et al. (2003, 0402661:42Engling et al. (2006,1564221:43Yu et al. (2005,1571671:44Tran et al. (2000, 0130251:45Yao et al. (2004,1022131:4BLi and Yu (2005,
    156692): "Henning et al. (2003,156539): 4BZhang and Anastasio (2003,157182): "Emmenegger et al. (2007,156418):50 Watson et al, (1989,157119): 51Greaves et al. (1985,156494): 52Waterman et al.
    (2000,1571161:53Waterman et al. (2001,1571171: aFalkovich and Rudich (2001,1564271:55Chow et al. (2007,1572091:5BMiguel et al. (2004,1232601:57Crimmins and Baker (2006, 0970081:5BHo and Yu
    (2004,1565511:59Jeon et al. (2001, 0166361: BOMazzoleni et al. (2007, 0980381: B1Poore (2002, 0514441: B2Butler et al. (2003,1563131: B3Chow et al. (2006,1466221: MRussell et al. (2004, 0824531: B5Grover
    et al. (2006,138080): BBGrover et al. (2005, 090044): B7Schwab et al. (2006, 098449): BBHauck et al. (2004,156525): B8Jaques et al. (2004,155878): 70Rupprecht and Patashnick (2003,157207): 71Pang et al
    (2002, 0303531:72Eatough et al. (2001, 0103031:73Lee et al. (2005,128139); MLee et al. (2005,1566801:75Babich et al. (2000,1562391:7BLee et al. (2005,1559251:77Lee et al. (2005,1281391:7BAnderson
    and Ogren (1998,1562131:79Chung et al. (2001,1563571: BOKidwell and Ondov (2004,1558981: B1Lithgow et al. (2004,1266161: B2Weber et al. (2003,1571291: B3Harrison et al. (2004,1367871: "Rattigan et
    al. (2006,115897): B5Wttig et al. (2004,103413): BBVaughn et al. (2005,157089): B7Chow et al. (2005, 099030): BBWeber et al (2001, 024640); B8Schwab et al. (2006, 098785): ™Lim et al. (2003, 037037):
    "Watson and Chow (2002, 0378731:82Venkatachari et al. (2006,1059181:83Bae et al. (2004,1562431: MArhami et al. (2006,1562241:85Park et al. (2005,1568431:8BBae et al. (2004, 0986801:87Chow et al.
    (2006,1563501:8BArnott et al. (2005,1562271:88Bond et al. (1999,1562811:1DDVirkkula et al.  (2005,1570971:1D1Petzold et al. (2002,1568631:102Park et al. (2006, 0981041:103Arnott et al. (1999, 0206501:
    "Veters et al. (2001, 016925): 105Pitchford et al. (1997,156872): 10BRees et al. (2004, 097164): 107Watson et al. (2000, 010354): 10BLee et al. (2005,156680): 108Hering et al. (2004,155837): ™Watson et al.
    (1998,1988051:111Chakrabarti et al. (2004,1574261:112Mathai et al. (1990,1567411: '"Kidwell and Ondov (2001.0170921: '"stanier et al. (2004, 0959551: '"Khlystovet al. (2005,1566351:11BTakahama et
    al. (2004,1570381:117Chow et al. (2005,1563481: '"Zhang et al. (2002,1571811:  '"Subramanian et al. (2004, 0812031:120Chow et al. (2006,1552071:  ™Birch and Cary (1996, 0260041:122Birch (1998,
    024953): 123Birch and Cary (1996, 002352): ™NIOSH (1996, 156810): 125NIOSH (1999, 156811): 12BChow et al. (1993, 077459): 127Chow et al. (2007, 156354): ™Ellis and Novakov (1982, 156416):
    128Peterson and Richards (2002,1568611:130Schauer et al. (2003, 0370141: "iMiddlebrook et al. (2003, 0429321: "2Wenzel et al. (2003,1571391: "3Jimenez et al. (2003,1566111: "Vhares et al. (2003,
    1568661:135Qin and Prather (2006,1568951: "BZhang et al. (2005,1571851:137Bein et al. (2005,1562651: "BDrewnick et al. (2004,1557541:  "8Drewnick et al. (2004,1557551: "°Lake et al. (2003,1566691:
    "'Lake etal. (2004, 088411)
    
    
    
                                                                                                                                     Source: Chow etal. (2008,156355)
    December  2009
                                    A-16
    

    -------
    Table A-8.     Measurement and analytical specifications for continuous S04
                                                                                                2-
     Instrument and Measurement Principle
    Averaging Analytical
       Time    Accuracy3
    Precision   MDL
                                                                                                                       Data
                        Interferences Comparability Comp|eteness
    FLASH VOLATILIZATION INSTRUMENTS
    
    Aerosol Dynamics, Inc. continuous sulfate
    analyzer (ADIS) , . ,3
    Particle collection by impaction followed by flash 10 min N/A N/A ^VS"" N/A
    volatilization and detection of the evolved gases
    by a UV-fluorescence S02 analyzer.
    
    Within 15% of
    filter and
    continuous
    S042" 100%7
    See Weber etal.
    for details.
    Rupprecht and Patashnick continuous sulfate
    analyzer (R&P-8400S)
    Particle collection by impaction followed by flash
    volatilization and detection of the evolved gases  10 min
    by a UV-fluorescence S02 analyzer. An
    activated carbon denuder at the inlet to the
    Nafion humidifier removes S02.
               N/A
    9 ug/m3   0.48 ug/m3 efficiency
    and >30%            appears to
    at cone.              depend on
    <2ug/m3b            ambient
                        composition
                                      10-30% lower
                                      than filter S042
                                      20,21,84
                                                                           84_ gg0/0 6,20,21,84,85
    THERMAL REDUCTION INSTRUMENTS
    Continuous Ambient Sulfate Monitor (CASM)
    Sampled air passes through a Na2C03 coated
    annular denuder to remove ambient S02 and is
    subsequently split into independent sample and
    filter flows. The sample flow passes through a
    quartz tube containing a stainless steel rod
    maintained at 1000 °C that reduces sulfate to
    S02. The flow then passes through a PTFE filter
    and into a trace-level S02fluorescence
    analyzer.
    .icmin
    lsmm
               M/A
               ™rt
                          M/A
                          ™rt
                                    N/A
                                              N/A
                                      Up to 25% lower
                                      than filter S042~
                                      and within 6%
                                      ofR&P8400S,
                                      PILS-IC and
                                      AMS 20<21
    SAMPLE DISSOLUTION FOLLOWED BY 1C ANALYSIS INSTRUMENTS
                                                                             an Qoo/ 20
                                                                             8°-98/0
    
    Thermo Electron Model 5020 sulfate particulate
    analyzer (TE-5020) 15 . N/A
    The commercial version of CASM, with slight lsmm N/rt
    changes in the sample flow path.
    
    0.3 ug/m3
    <10%<89 3Vg89 ,
    0 5 ug/m
    for 15-min
    avgd
    S042 toS02
    conversion
    efficiency
    depends on
    ambient
    composition 89
    
    -20% lower
    than filter S04
    
    
    
    88-90%89
    
    
    Energy Research Center of the Netherlands
    (ECN) IC-based ion analyzer
    Entrains particles into water drops using the
    steam jet aerosol collector. The drops are
    collected using a cyclone and the combined
    flow from collected droplets containing dis-
    solved aerosol components and wall steam
    condensate is directed to an anion 1C for
    analysis of sulfate. Interfering gases are pre-
    removed by a rotating wet annular denuder
    system.
    1 h
               N/A
                          N/A
                                    N/A
                                              N/A
                                      Within 15% of
                                      filter and
                                      continuous
                                      S042"
    
                                      See Weber etal.
                                      82 for details.
                                                                               100%
    Texas Tech University (TT) ion analyzer
    Particles in the sample stream, after being
    processed through a cyclone and a parallel
    plate wet denuder, are collected alternatively on
    one of two 2.5 cm pre-washed glass fiber filters 30 min N/A
    for a period of 1 5 min. The particles on the
    freshly sampled filter are automatically
    extracted for 6.5 min with water and analyzed
    for sulfate by 1C.
    Particle into Liquid Sampler-Ion
    Chromatography (PILS-IC)
    Ambient particles are mixed with saturated
    water vapor to produce droplets collected by 1 h N/A
    impaction. The resulting liquid stream is
    analyzed with an 1C to quantify aerosol ionic
    components.
    N/A N/A N/A
    n x , Consistent
    10%-15%e niR,,n/m3 water quality is
    0.18 ug/m essen^a|fj
    good precision.
    Within 15% of
    filter and
    continuous ,
    S042" 100%7
    See Weber etal.
    for details.
    Within 30% of
    filter and other fi/- ,„„ 20,21
    continuous DO-/U/O
    S042" 20'21
    December  2009
                        A-17
    

    -------
     Instrument and  Measurement Principle
    Averaging Analytical
       Time     Accuracy3
                  Precision    MDL
                                                                                                                                                         Data
    Interferences  Comparability  Comp|eteness
    Dionex-IC
    The gas-denuded air stream enters the annular
    channel of a concentric nozzle, where deionized
    water generates a spray that entrains the
    particles. The flow is then drawn through a 0.5-
     um pore size PTFE filter. The remaining
    solution is aspirated by a peristaltic pump  and
    sent to 1C for ion analysis.
                                                           Consistent
                                 11%-      N/A         ^rquaNtyis   W^1Q%of
    
                                                           good precision.
                                                                                        N/A
    Ambient Ion Monitor (AIM; Model 9000)
    Air is drawn through a size-selective inlet into a
    liquid diffusion denuder where interfering gases
    are removed.  The stream enters a super
    saturation chamber where the resulting droplets
    are collected through impaction. The collected
    particles and a fraction of the condensed water
    are accumulated until the particles can be
    injected into 1C for hourly analysis.
    1h
                  N/A
                  N/A         forlTavg  N/A
                                                                             N/A
                                                                                                       N/A
    PARTICLE MASS SPECTROMETER
    Aerosol Mass Spectrometer (AMS)
    Airstream is drawn through an aerodynamic
    lens and focused into a beam in a vacuum
    chamber. This aerosol beam is chopped by a
    mechanical chopper and the flight time of the
    particles through a particle-sizing chamber is
    determined by the time-resolved mass
    spectrometer measurement. The particle
    impacts onto a 600  °C heated  plate where it
    decomposes and is analyzed by a quadruple
    mass spectrometer. The sulfate ion, along with
    other ions, is detected by the mass
    spectrometer.
    A few
    seconds
    N/A
                  N/A
                                N/A
    Subject to
    interferences
    from fragments
    of other species  Up to 30% lower
    with mass to     than filter S042~
    charge ratio in    and within 5%
    the same range  of R&P8400S,
    as fragments of  PILS-IC and
    sulfate. Highly   CASM 20'21
    refractory
    materials are
    not detected.
                                                                                    93-98%2
    3 Accuracy is the ability of analytical methods to quantify the observable of a standard reference material correctly; does not refer to measurement accuracy, since no standards available.
    b Overall uncertainty estimated by error propagation.
    c Co-located precision estimate based on regression slope (slope = 0.95, intercept = 0.01-0.2, R >0.98).
    d Manufacturer specified measurement parameter.
    s Uncertainty estimated from uncertainties in flow rates and calibrations; does not refer to co-located precision.
    ' Co-located precision with respect to PC-BOSS PM25 S042~.
    N/A: Not available
    
    
    
    'Chow (1995, 0770121:2Watson and Chow (2001,1571231:3 Watson et al. (1983, 0450841:4Fehsenfeld et al. (2004,1573601:5Solomon et al. (2001,1571931: BWatson et al. (2005,1571241:7Mikel (2001,
    1567621: BWatson et al. (1999, 0209491:8Solomon and Sioutas (2006,1569951:1DGraney et al. (2004, 0537561: "Tanaka et al. (1998,1570411:12Pancras et al. (2005, 0981201: "John et al. (1988, 0459031:
    "Hering and Cass (1999, 084958): 15Fitz et al. (1989, 077387): 1BHering et al. (1988, 036012): "Solomon  et al. (2003,156994):  1BCabada et al. (2004,148859): "Fine et al. (2003,155775): 20Hogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 0991601:22Watson et al. (2005,1571251:23Ho et al. (2006,1565521:24Decesari et al. (2005,1445361:25 Mayol-Bracero et al. (2002, 0450101:2BYang et al. (2003,
    1561671:27Tursic et al. (2006,1570631:2BMader et al.(2004,1567241:28Xiao and Liu (2004, 0568011:30Kiss et al. (2002,1566461:31Cornell and Jickells (1999,1563671:32 Zheng et al. (2002, 0261001:
    33Fraser et al. (2002,140741): x Fraser et al. (2003, 042231) 35Schauer er al. (2000, 012225): 3BFine et al. (2004,141283): 37Yue et al. (2004,157169): 3BRinehart et al. (2006,115184):  38Wan and Yu (2006,
    1571041:40Poore (2000, 0128391:41Fraser et al. (2003, 0402661:42Engling et al. (2006,1564221:43Yu et al. (2005,1571671:44Tran et al. (2000, 0130251:45Yao et al. (2004,1022131:4BLi and Yu (2005,
    1566921: "Henning et al. (2003,1565391:4BZhang and Anastasio (2003,1571821:48Emmenegger et al. (2007,1564181:50 Watson et al, (1989,1571191:51Greaves et al. (1985,1564941:52Waterman et al.
    (2000,157116): 53Waterman et al. (2001,157117): aFalkovich and  Rudich (2001,156427): 55Chow et al. (2007,157209): 5BMiguel et al. (2004,123260): 57Crimmins and Baker (2006, 097008): 5BHo and Yu
    (2004,1565511:58Jeon et al. (2001, 0166361: BDMazzoleni et al. (2007, 0980381: B1Poore (2002, 0514441:B2Butler et al. (2003,1563131:  B3Chow et al. (2006,1466221: "Russell et al. (2004, 0824531: B5Grover
    et al. (2006,1380801: BBGrover et al. (2005, 0900441: B7Schwab et al. (2006, 0984491: BBHauck et al. (2004,1565251: B8Jaques et al. (2004,1558781:7DRupprecht and Patashnick (2003,1572071:71Pang et al
    (2002, 030353): 72Eatough et al. (2001, 010303):  73Lee et al. (2005,128139); MLee et al. (2005,156680): 75Babich et al. (2000,156239): 7BLee et al. (2005,155925): 77Lee et al. (2005,128139): 7BAnderson
    and Ogren (1998,1562131:78Chung et al. (2001,1563571: BOKidwell and Ondov (2004,1558981: B1Lithgow et al. (2004,1266161: B2Weber et al. (2003,1571291: B3Harrison et al. (2004,1367871: MRattigan et
    al. (2006,1158971: B5Wttig et al. (2004,1034131:  BBVaughn et al. (2005,1570891: B7Chow et al. (2005, 0990301: BBWeber et al (2001, 0246401; B8Schwab et al. (2006, 0987851:8DLim et al. (2003, 0370371:
    81Watson and Chow (2002, 037873): 82Venkatachari et al. (2006,105918): 83Bae et al. (2004,156243): 84Arhami et al. (2006,156224): 85Park et al. (2005,156843): ™Bae et al. (2004, 098680): 87Chow et al.
    (2006,1563501:8BArnott et al. (2005,1562271:  "Bond et al. (1999,1562811: "°Virkkula et al. (2005,1570971:101Petzold et al. (2002,1568631: "2Park et al. (2006, 0981041:103Arnott et al. (1999, 0206501:
    "Veters et al. (2001, 0169251:105Pitchford et al.  (1997,1568721: "BRees et al. (2004, 0971641:107Watson et al. (2000, 0103541: "BLee et al. (2005,1566801: "8Hering et al. (2004,1558371: ™Watson et al.
    (1998,198805): 111Chakrabarti et al. (2004,157426): 112Mathai et al. (1990,156741): '"Kidwell and Ondov (2001,017092): '"Stanier et al. (2004, 095955): '"Khlystovet al. (2005,156635): '"Takahama et
    al. (2004,1570381:117Chow et al. (2005,1563481:11BZhang et al. (2002,1571811: '"Subramanian et al. (2004, 0812031:120Chow et al. (2006,1552071: "1 Birch and Cary (1996, 0260041:122Birch (1998,
    0249531: 123Birch and Cary (1996, 0023521: ™NIOSH (1996, 1568101:125NIOSH (1999, 1568111:12BChow et al. (1993, 0774591: 127Chow et al. (2007, 1563541: 12BEllis and Novakov (1982, 1564161:
    128Peterson and Richards (2002,156861): 130Schauer et al. (2003, 037014): "iMiddlebrook et al. (2003, 042932): "2Wenzel et al. (2003,157139): "3Jimenez et al.  (2003,156611): "Vhares et al. (2003,
    1568661:135Qin and Prather (2006,1568951: "BZhang et al. (2005,1571851:137Bein et al. (2005,1562651: "BDrewnick et al. (2004,1557541: "8Drewnick et al. (2004,1557551: MOLake et al. (2003,1566691:
    "'Lake etal. (2004, 088411)
    
    
    
                                                                                                                                     Source: Chow etal. (2008,1563551
    December  2009
                              A-18
    

    -------
    Table A-9.      Measurement and analytical specifications for ions other than  N03" and S04
                                                                                                                                              2-
        Instrument and Measurement      Averaging  Analytical  „    •  •
                     Principle                     Time     Accuracy3  Precislon
                                                 MDL
                                                                                                         Data
                                                             Interferences  Comparability  Comp|eteness
    SAMPLE DISSOLUTION FOLLOWED BY 1C ANALYSIS INSTRUMENTS
    N02  by Particle into Liquid Sampler-Ion
    Chromatography (PILS-IC)
    Ambient particles are mixed with saturated
    water vapor to produce droplets collected
    by impaction. The resulting liquid stream is
    analyzed with an 1C to quantity aerosol
    ionic  components.
                                                            Consistent water
    1h
                  N/A          10%b88     0.14ug/m
                                                                               N/A
                                                                                                  N/A
                                                            good precision
    NH4+ by Particle into Liquid Sampler-Ion
    Chromatography (PILS-IC)
    Ambient particles are mixed with saturated
    water vapor to produce droplets collected
    by impaction. The resulting liquid stream is
    analyzed with an 1C to quantity aerosol
    ionic components.
    1h
                                              0,5ug/m'
                                                            Consistent water
                                                            good precision
    CI", Na+, K+, Ca" by Particle into Liquid
    Sampler-Ion Chromatography (PILS-IC)
    Ambient particles are mixed with saturated
    water vapor to produce droplets collected
    by impaction. The resulting liquid stream is
    analyzed with an 1C to quantity aerosol
    ionic  components.
    1h
                                                            Consistent water
    
                  N/A          10%b88      0.1ug/m388   ^jjjfo,       N/A
    
                                                            good precision
                                                                                                  N/A
    Cf, NO,", N03", P04^' S042", NH4+, Na+'
    Mg++, K , Ca" by Ambient Ion Monitor
    (AIM; Model 9000)
    Air is drawn through a size-selective inlet
    into a liquid diffusion denuder where
    interfering gases are removed. The  stream
    enters a super saturation chamber where
    the resulting droplets are collected through
    impaction. The collected particles and a
    fraction of the condensed water are
    accumulated until  the  particles can be
    injected into 1C for hourly analysis.
    1 h
                  N/A          N/A
                                             0.1 ug/m3for
                                             1-havgd       N/A
                                                                               N/A
                                                                                                  N/A
    3 Accuracy is the ability of analytical methods to quantify the observable of a standard reference material correctly; does not refer to measurement accuracy, since no standards are available.
    b Uncertainty estimated from uncertainties in flow rates and calibrations; does not refer to co-located precision.
    c All-sampler avg appears to include a combination of 10 integrated and 3 continuous samplers, although specific details are missing7. Performance evaluations at sites dominated by semi-volatile ammonium
    nitrate are needed.
    d Manufacturer specified measurement parameter
    
    
    
    1Chow (1995, 077012): 2Watson and Chow (2001,157123):3 Watson et al. (1983, 045084): 'Fehsenfeld et al. (2004,157360): 5Solomon et al. (2001,157193): "Watson et al. (2005,157124): 7Mikel (2001,
    1567621: "Watson et al. (1999, 0209491:8Solomon and Sioutas (2006,1569951:1DGraney et al. (2004, 0537561: "lanaka et al. (1998,1570411:12Pancras et al. (2005, 0981201: "John et al. (1988, 0459031:
    "Hering and Cass (1999, 0849581:15Fitz et al. (1989, 0773871:1BHering et al. (1988, 0360121: "Solomon et al. (2003,1569941:1BCabada et al. (2004,1488591:  "Fine et al. (2003,1557751:20Hogrefe et al.
    (2004, 099003): 21Drewnick et al. (2003, 099160): 22Watson et al. (2005,157125): 23Ho et al. (2006,156552): 24Decesari et al. (2005,144536):25 Mayol-Bracero et al. (2002, 045010): 2BYang et al. (2003,
    1561671:27Tursic et al. (2006,1570631:2BMader et al.(2004,1567241:28Xiao and Liu (2004, 0568011:30Kiss et al. (2002,1566461:31Cornell and Jickells (1999,1563671:32 Zheng et al. (2002, 0261001:
    33Fraser et al. (2002,1407411: x  Fraser et al. (2003, 042231135Schauer er al. (2000, 0122251:3BFine et al. (2004,1412831:37Yue et al. (2004,1571691:3BRinehart et al. (2006,1151841:38Wan and Yu (2006,
    157104): "Poore (2000, 012839): "Fraser et al. (2003, 040266): 42Engling et al. (2006,156422): 43Yu et al. (2005,157167): "Iran et al. (2000, 013025): <5Yao et al. (2004,102213): 4BLi and Yu (2005,
    1566921:47Henning et al. (2003,1565391:4BZhang and Anastasio (2003,1571821:48Emmenegger et al. (2007,1564181:50 Watson et al, (1989,1571191:51Greaves et al. (1985,1564941:52Waterman et al.
    (2000,1571161:53Waterman et al. (2001,1571171: aFalkovich and Rudich (2001,1564271:55Chow et al. (2007,1572091:5BMiguel et al. (2004,1232601:57Crimmins and Baker (2006, 0970081:5BHo and Yu
    (2004,156551): 58Jeon et al.  (2001, 016636): BOMazzoleni et al. (2007, 098038): B1Poore (2002, 051444):B2Butler et al. (2003,156313): B3Chow et al. (2006,146622): MRussell et al. (2004, 082453): B5Grover
    et al. (2006,1380801: BBGrover et al. (2005, 0900441: B7Schwab et al. (2006, 0984491: BBHauck et al. (2004,1565251: B8Jaques et al. (2004,1558781:7DRupprecht and Patashnick (2003,1572071:71Pang et al
    (2002, 0303531:72Eatough et al. (2001, 0103031:73Lee et al. (2005,128139); "Lee et al. (2005,1566801:75Babich  et al. (2000,1562391:7BLee et al. (2005,1559251:77Lee et al. (2005,1281391:7BAnderson
    and Ogren (1998,156213): 78Chung et al. (2001,156357): BOKidwell and Ondov (2004,155898): B1Lithgow et al. (2004,126616): B2Weber et al. (2003,157129): B3Harrison et al. (2004,136787): "Rattigan et
    al. (2006,115897): B5Wttig et al. (2004,103413): BBVaughn et al. (2005,1570891: B7Chow et al. (2005, 0990301: BBWeber et al (2001, 0246401; B8Schwab et al. (2006, 0987851: ™Lim et al. (2003, 0370371:
    81Watson and Chow (2002, 0378731:82Venkatachari et al. (2006,1059181:83Bae et al. (2004,1562431:84Arhami et al. (2006,1562241:85Park et al. (2005,1568431: ™Bae et al. (2004, 0986801:87Chow et al.
    (2006,156350): 8BArnott et al. (2005,156227): 88Bond et al. (1999,156281): "°Virkkula et al. (2005,157097): 101Petzold et al. (2002,156863): "2Park et al. (2006, 098104): 103Arnott et al. (1999, 020650):
    ""Peters et al. (2001, 016925): 105Pitchford et al. (1997,1568721: "BRees et al. (2004, 0971641:107Watson et al. (2000, 0103541: "BLee et al. (2005,1566801: "8Hering et al. (2004,1558371: ™Watson et al.
    (1998,1988051:111Chakrabarti et al. (2004,1574261:112Mathai et al. (1990,1567411: '"Kidwell and Ondov (2001.0170921: ™Stanier et al. (2004, 0959551: '"Khlystovet al. (2005,1566351:11BTakahama et
    al. (2004,157038): 117Chow et al. (2005,156348): '"Zhang et al. (2002,157181): '"Subramanian et al. (2004, 081203): "°Chow et al. (2006,155207): "'Birch and Cary (1996, 026004): "2Birch (1998,
    0249531: 123Birch and Cary (1996, 0023521: ™NIOSH (1996, 1568101:125NIOSH (1999, 1568111: "BChow et al. (1993, 0774591: "7Chow et al. (2007, 1563541: 12BEllis and Novakov (1982, 1564161:
    "8Peterson and Richards (2002,1568611:130Schauer et al. (2003, 0370141: "iMiddlebrook et al. (2003, 0429321: "2Wenzel et al. (2003,1571391: "3Jimenez et al. (2003,1566111: "Vhares et al. (2003,
    156866): 135Qin and Prather (2006,156895): "BZhang et al. (2005,157185): 137Bein et al. (2005,156265):  "BDrewnick et al. (2004,155754): "8Drewnick et al. (2004,155755): ""Lake et al. (2003,156669):
    "'Lake etal. (2004, 088411)
    
    
    
                                                                                                                                  Source: Chow etal. (2008,156355)
    December 2009
                                  A-19
    

    -------
    Table A-10.   Measurement and analytical specifications for continuous carbon.
    Instrument and Measurement Principle AvT[mge'ng Accuracy' Precision
               MDL
                                                  Data
    Interferences  Comparability Comp|eteness
    PARTICLE COLLECTION ON IMPACTOR FOLLOWED BY FLASH VOLATILIZATION INSTRUMENT
    Aerosol Dynamic Inc. continuous carbon
    analyzer (ADI-C)
    Particle collection by impaction followed by
    flash oxidation and detection of the evolved 10min N/A
    gases by a non-dispersive infrared C02
    analyzer. OC is estimated as twice the
    oxidizable carbon. EC is not quantified.
    OC:
    2 ug/m3
    EC.TC:
    N/A applicable, N/A
    since it
    measures
    only OC 90
    15-22% lower
    OC than that by KV, ?
    R&P-5400and OJ/0
    RU-OGI
    PARTICLE COLLECTION ON FILTER / IMPACTOR FOLLOWED BY HEATING/ANALYSIS INSTRUMENTS
    Rupprecht and Patashnick 5400 continuous
    ambient carbon analyzer (R&P-5400)
    Particles collected on an impactor, which is
    heated to 275 °C to 350 °C, then to 700 °C
    after sample collection is complete. Evolved 1 h N/A
    C02 is measured by an infrared detector. OC
    is defined as the carbon measured at the
    lower temperature, and EC is the remaining
    carbon measured at the higher temperature.
    Rutgers University-Oregon Graduate Institute
    (RU-OGI) in-situ thermal/optical transmittance
    carbon analyzer.
    Air is sampled through a quartz-fiber filter for
    1 h and then analyzed by heating through ,n • .,,„
    different temperature steps to determine OC JU ™ IN/M
    and EC. Sample flow is pre-split into two
    identical systems that alternate every hour
    between sampling and analysis mode to
    achieve continuous measurements.
    Sunset semi-continuous realtime carbon
    aerosol analysis instrument (Sunset OCEC)
    Particles collected on a quartz-fiber filter are
    subject to heating temperature ramps following
    the NIOSH 5040 TOT protocol and the 1h N/A
    resulting C02 is analyzed by nondispersive
    infrared (NDIR) detector to quantify OC and
    EC. Instrument is alternated between sampling
    and analytical mode.
    OC:
    0.5 ug/m
    N/A O^ug/m3 N/A
    TC:
    0.5 ug/m390
    OC:
    0.3 ug/m
    3%b'? 0E5:ug/m3 N/A
    TC:
    0.4 ug/m390
    OC:10%C Ir^N/A
    EC:20%C if0,. N/A .,,„
    TC-10%C TC' 3 N/A
    JsV07" 0.4 ug/m3
    (1-havg)95
    20 to 60% lower
    TC than filter TC cc cno/ 6,91
    by TOR or 56-60%
    TOT.91'92
    8% higher OC
    and 20% lower aRO/ ?
    ECthanR&P- 86/0
    5400 90
    Within 7 to 25%
    of filter OC and
    EC and within
    15%forTC.
    Wide variation Qn ano/ 6-95
    due to different- 8°-89/0
    ces in tempera-
    ture and
    analysis
    protocols. 92'95'96
    LIGHT ABSORPTION INSTRUMENTS
    Aethalometer (AE-1 6, AE-21 , AE-31)
    Attenuation of light transmitted through a
    quartz-fiber filter tape that continuously sam- ,- , .,,„
    pies aerosol is measured and converted to a
    BC mass concentration using oabs of 14625/A
    (m2/g).
    Subject to multi-
    ple scattering
    effects by parti-
    cle and filter
    matrix resulting
    5t BCe. in absorption
    lore- 0.1 ug/m39' |;— •
    rections have
    been proposed
    98 that can cor-
    rect for such
    effects.
    Within ± 25% of
    RU-OGI, Sunset 7CQno/6
    and filter EC by 75-90/0
    TOR/TOT.90'92
    December 2009
    A-20
    

    -------
    Instrument and Measurement Principle AvT[mge'ng Accuracy'  Precision
                                       MDL
                                                                                Data
               Interferences Comparability Comp|eteness
    
    
    
    Particle Soot Absorption Photometer (PSAP)
    Attenuation of light transmitted through a
    glass-fiber filter that continuously samples 1 min N/A
    aerosol is measured to quantify light
    absorption (babs).
    
    
    
    
    
    
    
    Multi-Angle Absorption Photometer (MAAP)
    Light transmittance at 0° and reflectance from
    a glass-fiber filter at 130° and 165° from the . • .,,„
    illumination direction are used in a radiative
    transfer model to estimate babs and is
    converted to BC using oabs of 6.6 m2/g.
    
    
    
    
    
    
    DRI Photoacoustic Analyzer (DRI-PA)
    Light absorption by particles in air results in a
    heating of the surrounding air. The expansion
    of the heated air produces an acoustic (sound
    wave) signal which is detected by a micro- 5 s N/A
    phone to determine babs, which is converted
    to BC using oabs = 5 m2/g for the 1047 nm
    instrument and oabS = 10 m2/g for the 532 nm
    in^tn impnt
    II loll Ul 1 ICl II.
    
    
    
    
    
    6 to BCf:
    8%"<100 0.1 ug/m390
    
    
    
    
    BCh:
    0.05 ug/m3
    (or
    babs = 0.33
    Mm for
    10-min
    12%9'101 avg)
    0.02 ug/m
    (or
    babs = 0.13
    Mm for
    30-min
    avg)1"1
    
    
    
    BC1:
    0.04 ug/m
    (or
    M/A bate - 0.4
    N/A Mm'1 for
    10-min
    avg) at
    532 nm103
    
    
    
    Instrument in-
    cludes an em-
    pirical correction
    for scattering
    and loading ef-
    fects 99 and
    adjustments
    have been pro-
    posed for the
    three wave-
    length model
    100
    The instrument
    is designed to
    minimize mul-
    tiple scattering
    and loading ef-
    fects by mea-
    suring both
    transmittance
    and reflectance
    and using a
    two-stream
    approximation
    radiative
    transfer model
    to calculate babs.
    At 532 nm,
    absorbance by
    N02 interferes
    with that by
    particles. Ac-
    counted by
    either removing
    N02 from sam-
    ple line using
    denuders or by
    doing a periodic
    background
    (particle-free
    air) subtraction.
    
    
    
    -50% lower
    thanAE-16,RU-
    OGI and R&P-
    5400 EC.90
    
    
    
    
    
    
    
    Within 18% of
    filter EC by
    IMPROVE TOR
    (R2 = 0.96) and
    up to 40%
    higher than
    Sunset EC. 102
    
    
    
    
    
    
    Good correlation
    (R2 >0.80), but
    more than 40%
    lower than
    aethalo meter,
    MAAP and filter
    IMPROVE_TOR
    EC. Suggests
    need for a
    different oabs. 102
    
    
    
    
    
    N/A
    
    
    
    
    
    
    
    N/A
    
    
    
    
    
    
    N/A
    
    
    
    PHOTO-IONIZATION INSTRUMENTS
    Photoionization monitor for polycyclic aromatic
    hydrocarbons (PAS-PAH) The air stream is
    exposed to UV radiation, which ionizes the
    particle-bound PAH molecules. The charged
    particles are collected on a filter element and
    the piezoelectric current is proportional to the
    particle-bound PAH.
    5 min
               N/A
                          N/A
    ~3ng/mJ1'K  N/A
                                                            N/A
                                                                           >91%6
    December 2009
                         A-21
    

    -------
    Instrument and Measurement Principle
    >lng  tSSSSf  Precision      MDL     Interferences  Comparability  Com°ae?eness
    3 Accuracy is the ability of analytical methods to quantify the observable of a standard reference material correctly; does not refer to measurement accuracy, since no standards are available.
    b No specific details on how the precision was estimated; appears to be based on replicate analysis, may not represent overall co-located measurement precision
    c Co-located precision estimates based on variation in avg ratios of replicate analysis using laboratory instrument and regression slopes (Slopes for OC = 1.01, EC = 0.82, TC = 0.94; R2 = 0.97-0.99) of co-
    located field measurements.
    d Estimated using co-located AE-21 and AE-31 BC measurements at Fresno, CA.97
    e While the default manufacturer recommended conversion factor (or mass absorption efficiency, oabs) is 16.6 m2/g at 880 nm, Lim et al. (2003, 037037) assumed a value of 12.6 m2/g.
    f Assuming a oabs of 10 m2/g.
    9 Co-located precision estimate based on the variability of the avg ratio (0.99 ± 0.12).
    hAssuming a oabs of6.5 m2/g.
     Assuming a oabs of 10m2/g at 532 nm and 5 m2/g at 1047 nm.
    J Specified by manufacturer as "lower threshold"; needs to be calibrated with site-specific PAH. Typically used as a relative measure in terms of electrical output in femtoamps.
    k Manufacturer specified measurement parameter
    N/A: Not available.
    
    
    1Chow (1995, 077012): 2Watson and Chow (2001,157123):3 Watson et al. (1983, 045084): 4Fehsenfeld et al. (2004,157360): 5Solomon et al. (2001,157193): BWatson et al. (2005,157124): 7Mikel (2001,
    156762): "Watson et al. (1999, 020949): 8Solomon and Sioutas (2006,156995): 10Graney et al. (2004, 0537561: "lanaka et al. (1998,1570411:12Pancras et al. (2005, 0981201: "John et al. (1988, 0459031:
    "Hering and Cass (1999, 0849581:15Fitz et al. (1989, 0773871:1BHering et al. (1988, 0360121: "Solomon et al. (2003,1569941:1BCabada et al. (2004,1488591: "Fine et al. (2003,1557751:2DHogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 099160): 22Watson et al. (2005,157125): 23Ho et al. (2006,156552): 24Decesari et al. (2005,144536):25 Mayol-Bracero et al. (2002, 045010): 2BYang et al. (2003,
    156167): 27Tursic et al. (2006,1570631:2BMader et al.(2004,1567241:28Xiao and Liu (2004, 0568011:30Kiss et al. (2002,1566461:31Cornell and Jickells (1999,1563671:32 Zheng et al. (2002, 0261001:
    33Fraser et al. (2002,1407411: M  Fraser et al. (2003, 042231135Schauer er al. (2000, 0122251:3BFine et al. (2004,1412831:37Yue et al. (2004,1571691:3BRinehart et al. (2006,1151841:38Wan and Yu (2006,
    157104): "Poore (2000, 012839): 41Fraser et al. (2003, 040266): 42Engling et al. (2006,156422): 43Yu et al. (2005,157167): 44Tran et al. (2000, 013025): 45Yao et al. (2004,102213): 4BLi and Yu (2005,
    156692): "Henning et al. (2003,156539): 4BZhang and Anastasio (2003,1571821: <8Emmenegger et al. (2007,1564181:50 Watson et al, (1989,1571191:51Greaves et al. (1985,1564941:52Waterman et al.
    (2000,1571161:53Waterman et al. (2001,1571171: aFalkovich and Rudich (2001,1564271:55Chow et al. (2007,1572091:5BMiguel et al. (2004,1232601:57Crimmins and Baker (2006, 0970081:5BHo and Yu
    (2004,1565511:58Jeon et al. (2001, 0166361: BOMazzoleni et al. (2007, 098038): B1Poore (2002, 051444): B2Butler et al. (2003,156313): B3Chow et al. (2006,146622): MRussell et al. (2004, 082453): B5Grover
    et al. (2006,1380801: BBGrover et al. (2005, 0900441: B7Schwab et al. (2006, 0984491: BBHauck et al. (2004,1565251: B8Jaques et al. (2004,1558781:70Rupprecht and Patashnick (2003,1572071:71Pang et al
    (2002, 0303531:72Eatough et al. (2001, 0103031:73Lee et al. (2005,128139); MLee et al. (2005,1566801:75Babich  et al. (2000,1562391:7BLee et al. (2005,1559251:77Lee et al. (2005,1281391:7BAnderson
    and Ogren (1998,156213): 78Chung et al. (2001,156357): BOKidwell and Ondov (2004,155898): B1Lithgow et al. (2004,126616): B2Weber et al. (2003,157129): B3Harrison et al. (2004,136787): "Rattigan et
    al. (2006,1158971: B5Wittig et al. (2004,1034131: BBVaughn et al. (2005,1570891: B7Chow et al. (2005, 0990301: BBWeber et al (2001, 0246401; B8Schwab et al. (2006, 0987851:80Lim et al. (2003, 0370371:
    81Watson and Chow (2002, 0378731:82Venkatachari et al. (2006,1059181:83Bae et al. (2004,1562431:84Arhami et al. (2006,1562241:85Park et al. (2005,1568431:8BBae et al. (2004, 0986801:87Chow et al.
    (2006,1563501:8BArnott et al. (2005,156227): 88Bond et al. (1999,156281): 1DDVirkkula et al. (2005,157097): 1D1Petzold et al. (2002,156863): 102Park et al. (2006, 098104): 103Arnott et al. (1999, 020650):
    ""Peters et al. (2001, 0169251:105Pitchford et al. (1997,1568721:10BRees et al. (2004, 0971641:107Watson et al. (2000, 0103541: ™Lee et al. (2005,1566801:108Hering et al. (2004,1558371: ™Watson et al.
    (1998,1988051: '"Chakrabarti et al. (2004,1574261:112Mathai et al. (1990,1567411: '"Kidwell and Ondov (2001.0170921: ™Stanier et al. (2004, 0959551: '"Khlystovet al. (2005,1566351:11BTakahama et
    al. (2004,1570381:117Chow et al. (2005,156348): '"Zhang et al. (2002,157181): '"Subramanian et al. (2004, 081203): 120Chow et al. (2006,155207): ™Birch and Cary (1996, 026004): 122Birch (1998,
    024953): 123Birch and Cary (1996, 0023521: ™NIOSH (1996,  1568101:125NIOSH (1999, 1568111:12BChow et al. (1993, 0774591: 127Chow et al. (2007, 1563541: ™Ellis and  Novakov (1982, 1564161:
    128Peterson and Richards (2002,1568611:130Schauer et al. (2003, 0370141: "iMiddlebrook et al. (2003, 0429321: "2Wenzel et al. (2003,1571391: "3Jimenez et al. (2003,1566111: "Vhares et al. (2003,
    156866): 135Qin and Prather (2006,156895):  "BZhang et al. (2005,157185): 137Bein et al. (2005,156265): "BDrewnick et al. (2004,155754): "8Drewnick et al. (2004,155755): "°Lake et al. (2003,156669):
    "'Lake etal. (2004, 088411)
    
    
                                                                                                                                                 Source: Chow etal. (2008,156355)
    December  2009
                         A-22
    

    -------
    Table A-11.   Summary of mass measurement comparisons.
    Site / Period / Sampler / Configuration
    1 . Birmingham, AL (11/04/96 To 11/23/96)
    2. Denver-Adams City, CO (12/11/96 To 1/7/97)
    3. Bakersfield, CA (1/21/97 To 3/19/97)
    4. Denver-Welby, Co (12/12/96 To 12/21/96)
    5. Phoenix, AZ (12/06/96 To 12/21/96)
    6. Azusa, CA (3/25/97 To 5/1 9/97)
    7. Research Triangle Park (RTP), NC (1/17/97 To 8/14/97)
    8. Rubidoux, CA (1/6/99 To 2/26/99)
    9. Atlanta, GA (8/3/99 To 8/31/99)
    Sampler Flow Rate (L/Min) Filter Type"
    RAAS2.5-100 ,R7
    PM2.5FRM ID-'
    RAAS2.5-300 ,R7
    PM2.5FRM ID-'
    RAAS2.5-200 ,R7
    PM2.5FRM ID-'
    R&P Partisol 2000 1R7
    PM2.5FRM ID-'
    R&P Partisol-plus 1R7
    2025PM2.5FRM ID''
    BGIPQ200PM25 1R7
    FRM lb''
    Sierra Instruments 1R 7
    SA-244Dichot ID''
    IMPROVE PM2.5 22.8
    Harvard PM2.5 .,,
    Impactor
    Airmetrics battery
    powered PM2.5 5
    MiniVol
    Teflon (N/A)
    Teflon (N/A)
    Teflon (N/A)
    Teflon (N/A)
    Teflon (N/A)
    Teflon (N/A)
    Teflon (N/A)
    Teflon (N/A)
    Teflon (N/A)
    Teflon (N/A)
    Denuder
    None
    None
    None
    None
    None
    None
    None
    None
    None
    None
    Atlanta Supersite, GA: 8/3/99 to 9/1/99
    Four km NW of downtown, within 200 m of a bus maintenance yard and several
    warehouse facilities, representative of a mixed commercial-residential neighborhood.
    Flow
    Sampler Rate
    (L/Min)
    R&P-2000FRM 16.7
    RAAS-100FRM 16.7
    RAAS-400 24
    SASS 6.7
    MASS-400 16.7
    R&P-2300 10
    R&P-2025 Dichot:
    PM2.5 15
    PM10-15 1.67
    URG-PCM 16.7
    ARA-PCM 16.7
    PC-BOSS ,n,
    (operated by TVA) lu&
    Filter Type3
    Teflon (P)
    Teflon (P)
    Teflon (P)
    Teflon (P)
    Teflon (P)
    Teflon (P)
    
    Teflon (P)
    Polycarbonate
    Teflon (P)
    Teflon (N/A)
    Teflon (W)
    Denuder1'
    None
    None
    None
    None
    Na2C03
    None
    
    None
    None
    Na2C03/Citric
    Acid
    Na2C03/Citric acid
    GIF
    Summary of Findings
    Peters et al. (2001, 017108)104: Pitchford et al. (1997, 156872)105
    dataset
    Co-located precision (CV) for the RAAS2.5-100 samplers ranged
    from 1 .5% at Bakersfield to 6.2% at Birmingham.
    In Birmingham, CV for two co-located Harvard Impactor was 1% and
    for three Dichots was 6.2%. The IMPROVE samplers had greater
    variability, with a CV of 11 .3% (Denver-Adam City) and 1 0.8%
    (Bakersfield).
    Partisol and RAAS showed the strongest pairwise comparison
    (slope = 1 .0 ± 0.06, intercept = 0.26 ± 1 .81 , and correlation = 1 .0),
    within the EPA equivalency criteria. Strong relationships (correlation
    >0.96; slope = 0.9-1 .12, intercept < 3o) were observed for other
    samplers in reference to the RAAS.
    At Denver-Welby, 6 RAAS samplers were deployed (3 with and 3
    without temperature compensation for flow control). The units with
    temperature compensation had a positive bias relative to the non-
    temperature compensated units.
    Non-FRM samplers did not meet the EPA equivalency criteria,
    despite strong linear relationships with the FRM sampler.
    Peters et al. (2001 , 0169261104: RTP 97 dataset
    CVwas 1 .7%, 2.3%, 3.4%, 6.4% for the PQ200, Partisol 2000,
    RAAS2.5100, and Dichot, respectively. Dichot flows were valve
    controlled and set visually by the operator using rotameters.
    Good one-to-one correspondence was observed for FRM
    comparisons. The FRM averages were within -1 .2% to 3.2%, within
    the acceptable ±10% range
    Peters etal. (2001, 016925)104: Rubidoux 99 and Atlanta 99
    dataset
    In Rubidoux, the precision for PQ200 was 6.1 %, higher than at RTP
    97. In Atlanta, the grouped data from PQ200, RAAS2.5-300, and
    Partisol yielded a precision of 1.7%.
    Linear regression results met the EPA equivalency criteria for all
    FRMs.
    Solomon et al. (2003, 166994) 1T
    PM2 5 mass from individual samplers was compared to all-sampler
    avgs, called the filter relative reference (filter RR) value. Overall
    agreements were within ± 20% of filter RR.
    FRM samplers were within 3.5% of filter RR.
    Avg mass measured by RAAS-400, SASS and URG-PCM were
    within + 10% of filter RR. Avg mass measured by MASS-400, R&P-
    2300 and R&P-2025 dichot were greater than filter RR but
    within ± 20%. Avg mass measured by PC-BOSS (BYU) and ARA-
    PCM were lower than filter RR within ±10%.
    All samplers except PC-BOSS (TVA) had R2 >0.80, relative to filter
    RR.
    While avg mass for each sampler was within 20% , daily variability
    was >50% of filter RR.
    Glycerol in the Na2C03 denuder may have contaminated the filter in
    the MASS-400 sampler resulting in higher PM2.5 values.
    PC-BOSS samplers removed particles < 0.1 urn aerodynamic
    diameter from PM2.5 measurements. Corrections were made using
    sulfate (S042~) concentrations in the major flow or immediately after
    the PM2 5 inlet, but before the flow split-up. This was insufficient to
    bring PC-BOSS mass close to filter RR. PC-BOSS was also
    equipped with upstream denuders ahead of the filters, which may
    have enhanced loss of semi-volatile components, resulting in a lower
    mass on the filter.
    December 2009
    A-23
    

    -------
    Site / Period / Sampler / Configuration
    PC-BOSS ,,-n
    (operated by BYU) lou
    PIVhs Continuous pf
    SamP'er (UMin)
    TEOM 16.7
    Teflon (W)
    Inlet Temperature
    30 °C
    GIF
    Dryer Other
    Nafion PM2.5
    Atlanta Supersite, GA: 11/21/01 to 12/23/01
    Flow
    PIVh.s Sampler Rate
    (L/Min)
    R&P-2025FRM 16.7
    PIVhs Continuous pT
    Sampler [»•„,
    TEOM 16.7
    SES-TEOM 16.7
    CAMM 0.3
    RAMS 16.7
    Radiance .,,„
    Research M903 ™rt
    Radiance .,,„
    Research M903 ™rt
    PITTSBURGH SUPERSITE,
    park on the top of a hill
    Flow
    Sampler Rate
    (L/Min)
    MOUDI-110 30
    And-241 Dichot 16.7
    R&P-2000PM25 1R7
    FRM lb''
    PM2.s Continuous p °w
    Sampler [»•„,
    SES-TEOM 16.7
    DAASS N/A
    
    Filter Type3
    Teflon (N/A)
    Inlet Temperature
    30 °C
    30 °C
    N/A
    30 °C
    N/A
    N/A
    Denuded
    None
    Dryer Other
    Nafion PM2.5
    Nafion PM2.5
    Nafion PM2.5
    PM2.5
    TEA & GIF
    Nafion denuders With
    particle
    concentrator
    Nafion bscat
    None bscat
    PA: 7/1/01 to 6/1/02 6 km east of downtown in a
    Filter Type3
    Teflon (P,d)
    Teflon (P
    Teflon (W)
    Inlet Temperature
    30 °C
    30 °C
    
    Denuder
    None
    None
    None
    Dryer Other
    Nafion PM2.5
    Nafion or D,,
    None PM«
    
    Summary of Findings
    Butler etal. (2003, 156313)62
    The sum of individual species accounted for ~78% of the RAAS-100
    FRM PM25 mass concentration.
    TEOM explained -82 to 92% of the species sum of RAAS with
    R2=0.86.
    Lee etal. (2005, 128139)73
    RAMS PM2.5 adjusted using particle concentrator efficiency of 0.5.
    Good correlation between SES-TEOM and Radiance Research
    • M903s (R2 = 0.80), while medium correlation was found between
    CAMM and Radiance Research M903 (R2 = 0.64) or RAMS and
    Radiance Research M903 (R2 = 0.63).
    CAMM = (0.75 ± 0.03) SES-TEOM + (2.51 ± 0.51); R2 = 0.78;
    N = 196
    RAMS = (0.85 ± 0.06) SES-TEOM + (5.34 ± 1 .04); R2 = 0.52; N = 96
    RAMS = (0.91 ± 0.07) CAMM + (5.71 ± 1 .20); R2 = 0.43; N = 196
    Semi-volatile material explains the difference between RAMS and
    •SESTEOM.
    CAMM = (0.75 ± 0.08) R&P-2025 FRM + (2.47 ± 1 .02); R2 = 0.76;
    N = 31
    RAMS = (0.97 ± 0.22) R&P-2025 FRM + (2.39 ± 3.42); R2 = 0.64;
    N = 13
    SES-TEOM = (1 .07 ± 0.05) R&P-2025 FRM + (-1 .34 ± 0.71);
    R2=0.95;N = 26
    CAMM vs. FRM yielded lower slopes (0.75) with high intercepts.
    Cabada et al. (2004, 148869)18: Rees et al. (2004, 097164)106
    • MOUDI PM10 = 0.80 Dichot PM10, R2 = 0.85
    MOUDI PM2.5= 1 .03 Dichot PM2.5, R2 = 0.78
    MOUDI PM25= 1.01 FRM PM25,R2 = 0.78
    Dichot PM2 5 = 0.97 FRM PM2 5 + 0.02; R2 = 0.94
    Good agreement for PM25FRM, Dichot, and MOUDI. Lower slope for
    PMio suggests loss of coarse particles in the MOUDI sampler.
    Ultrafine (< 100 nm) mass (PM0.io) measurements had high
    uncertainties (-30%)
    Ultrafine mass by MOUDI showed no correlation with ultrafine
    volume (V0.10) by DAASS. Ratio of PM0.io/PM2.5 mass ratio showed
    reasonable agreement with volume ratio (V0.10/V2.5, R2 = 0.55,
    slope = 0.76). Bounce of large particles to smaller stages in MOUDI
    was small, since mass ratio (PM0.io/PM2.5) did not exceed volume
    ratio (V0.10/V2.5). Low correlation between ultrafine mass and
    volume could be due to the ultrafine mass measurement uncertainty
    or due to fundamental differences in the measurement methods
    employed by MOUDI and DAASS. Ambient conditions and
    characteristics of the aerosols (such as non-spherical shapes of fresh
    particles) could also influence these estimates.
    Rees et al. (2004, 0971641106
    SES-TEOM PM2.5 = 1 .02 FRM PM2.5 + 0.65; R2 = 0.95
    Volatilization did not affect SES-TEOM performance when PM2.5
    mass >20-30 ug/m3. When ambient temperature was < -6 °C, and
    when mass was low, SES-TEOM was lower (up to 50%) than FRM or
    Dichot.
    December 2009
    A-24
    

    -------
    Site / Period / Sampler / Configuration
    Summary of Findings
    FRESNO SUPERSITE, CA and other CRPAQS sites; 12/2/99 to 2/3/01 . Some Chow et al. (2006, 146622)63
    comparisons included data till 12/29/03 . Fresno Supersite was located 5.5 km _.. . . .. .. _.. . .... -.,. .
    northeast of downtown in a mixed residential-commercial neighborhood. '» ^^^t/rllJlS Z^^TtS? °f
    Sampler
    RAAS-100PM25
    FRM
    RAAS-300PM25
    FRM
    R&P-2000PM25
    FRM
    R&P-2025PM25
    FRM
    RAAS-400 PM2.5
    SASS PM2.5
    And-246 Dichot
    PM2.5
    PM 10-15
    DRI-SFS PM2.5
    MiniVol PM2.5
    MOUDI-100
    And-hlVOLPM10
    FRM
    Flow
    Rate
    (L/Min)
    16.7
    16.7
    16.7
    16.7
    24
    6.7
    
    15
    1.67
    113
    5
    30
    1130
    Filter Type3
    Teflon (P)
    Teflon (P)
    Teflon (P)
    Teflon (P)
    Teflon (P)
    Teflon (P)
    
    Teflon (P)
    Teflon (P)
    Teflon (P)
    Teflon (P)
    FEPb Teflon (P)
    Teflon (P)
    Denuder
    None
    None
    None
    None
    None
    None
    
    None
    None
    None
    None
    None
    None
    RAAS-300 FRM.
    All the FRM samplers were within ±10% of each other.
    All the tiller samplers were well correlated with each other (K*
    >0.90).e
    DRI-SFS (with HN03 denuder) and And-246 Dichot PM2.5were lower
    (~5% and 7%, respectively, on avg) than FRM, possibly due to nitrate
    (N03~ volatilization.
    Poor correlation (R2) found between TEOM PM25 concentrations and
    RAAS-100 FRM. TEOM PM25was lower than RAAS-100 FRM by
    22%. Heating of TEOM inlet to 50 °C resulted in loss of semi-volatile
    components such as ammonium nitrate (NH4N03) and possibly some
    semi-volatile organic compounds.
    TEOM PMm concentrations were 28% lower than the And-hlVOL10
    FRM on avg, ranging from 13% in summer to 43% in winter.
    TEOM was neither equivalente nor comparablee to the FRM sampler
    for PM, 5 or PM10
    BAM PM2 5 concentrations showed high correlation (R2 >0.90) with
    the RAAS-100 and RAAS-300 FRM samplers, with slopes ranging
    from 0 92 to 0 97 BAM PM2 5 was typically higher than FRM (1 7 to
    30%) except at Bakersfield, CA, where it was 21% lower, suggesting
    
    FRM concentration on avg (R >0.92).
    Higher BAM measurements were attributed to water absorption by
    hygroscopic particles. BAM PM2.5 and PMio deviations were larger for
                                                                         Groveretal. (2006,138080)65
    
                                                                         PC-BOSS PM25 = (0.88 ± 0.04) FDMS-TEOM + (6.7 ± 4.3); R2 = 95;
                                                                         n = 29
    
                                                                         PC-BOSS PM25 = (1.11 ± 0.07) D-TEOM + (7.5 ± 6.1); R2 = 0.90;
                                                                         n = 29
    
                                                                         TEOM50C PM25 = (0.80 ± 0.01) TEOm3OC + (1.1  ± 3.1); R2 = 0.91;
                                                                         n = 507
    
                                                                         TEOm3OC PM25 = (0.50 ±0.01) FDMS-TEOM -(1.7 ± 6.9); R2 = 0.68;
                                                                         n = 516
    
                                                                         Heated GRIMM PM concentrations were lower than FDMS-TEOM
                                                                         and ambient temperature GRIMM, suggesting loss of semi-volatile
                                                                         matter.
    
                                                                         Data recovery was greater than 95% for all continuous instruments,
                                                                         except for D-TEOM, which had 86% recovery.
    
                                                                         Reasonable agreement was seen between FDMS-TEOM, D-TEOM,
                                                                         BAM, and GRIMM PM25when semi-volatile matter was dominated by
                                                                         NH4N03. However, the FDMS-TEOM was higher than the other
                                                                         instruments during high concentration periods, associated with days
                                                                         with a high fraction of semi-volatile organic compounds (SVOCs).
                                                                         Possible differences in SVOCs may have contributed to the
                                                                         differences between FDMS and other instruments.
    Continuous Sampler
    TEOM
    BAM
    Sampler
    PC-BOSS PM2.5
    Flow Rate (L/Min)
    16.7
    16.7
    Flow Rate (L/Min)
    150
    Inlet
    Temperature
    50 °C
    Ambient
    Filter Type3
    Teflon (W)
    Dryer
    None
    None
    
    
    Other
    PM2.5andPM10
    PM2.5andPM10
    Denuder11
    GIF
    
    December 2009
    A-25
    

    -------
    Site / Period / Sampler / Configuration
    Continuous Sampler Flow Rate (L/Min) Temperature Dr^er
    TEOM 16.7 50 °C None
    TEOM 16.7 30 °C None
    FDMSTEOM 16.7 30 °C Nafion
    D-TEOM 16.7 30 °C Nafion
    GRIMM1100 1.2 Ambient None
    80 °C heater,
    GRIMM1100 1.2 aerosol9 '" Heater
    temperature
    BAM 16.7 Ambient None
    
    Other
    PM2.5
    PM2.5
    PM15
    PM2.5
    bscat
    bscat
    PM2.5
    HOUSTON SUPERSITE, TX; 1/1/00 to 2/28/02
    The Houston Supersite included three sites located in southeast Texas including one on the grounds
    of a municipal airport at the edge of a small community, one adjacent to the highly industrial ship
    channel and one on the grounds of a middle school in a suburban community.
    PM2.s Sampler Flow Rate (L/Min) Filter Type3
    R&P-2025FRM 16.7 Teflon (N/A)
    Continuous Sampler Flow Rate (L/Min) Temperature Or^er
    TEOM 16.7 50 °C None
    SES-TEOM 16.7 30 °C Nafion
    CAMM 0.3 Ambient Nafion
    RAMS 16.7 30 °C Nafion
    Radiance Research m m Nafjon
    Denuder
    None
    Other"
    PM2.5
    PM2.5
    Aug-Sep '00
    PM2.5
    Aug-Sep '00
    PM2.5
    TEA & GIF
    denuders; Aug-
    Sep '00
    Bscat Aug-Sep
    '00
    LOS ANGELES SUPERSITE, CA; 9/01 to 8/02
    The Los Angeles Supersite consisted of multiple sampling locations in the South Coast Air Basin to
    provide wide geographical and seasonal coverage, including urban "source" sites and downwind
    "receptor" sites.
    Sampler Flow Rate (L/Min) Filter Typea
    R&P-2025 Dichot
    PM2.5 15 Teflon (P)
    PM ,0-2.5 16.7 N/A
    MOUDI-110 30 Teflon (P
    HEADS PM2.5 10 Teflon (N/A)
    
    Continuous Sampler Flow Rate (L/Min) TemDerature Dryer
    D-TEOM 16.7 30 °C Nafion
    Nano-BAM
    (BAM-1 020 with d50 16.7 Ambient None
    148 ±10 nm inlet)
    Denuder1'
    
    None
    None
    None
    NaHC03
    
    Other
    PM2.5
    ~150 nm cut-
    point at 16.7
    L/min
    Summary of Findings
    
    Russell et al. (2004, 082463)64; Lee et al. (2005,
    166680)108
    Good correlations between 24-h SES-TEOM PM25
    . and R&P-2025 FRM mass.
    CAMM = (0.93 + 0.03) RAMS + (3.14 + 0.74);
    R2 = 0.81
    SES-TEOM = (0.92 ± 0.03) RAMS + (1 .52 ± 0.77);
    R2 = 0.80
    SES-TEOM = (1 .01 ± 0.03) CAMM + (-1 .91 ± 0.79);
    . R2 = 0.83
    Correlation of Radiance Research M903 and SES-
    TEOM was good (R = 0.95), while that of Radiance
    Research M903 with CAMM or RAMS was poor (R2
    -0.4).
    RAMS >SES-TEOM at high temperature and low
    RH (< 60%), suggesting loss of water and
    particulate N03 from SES-TEOM.
    CAMM = (1 .02 + 0.08) R&P-2025 + (1 .62 + 1 .35) ;
    R2 = 0.89
    RAMS = (1 .10 ± 0.08) R&P-2025 + (0.68 ± 1 .28);
    R2 = 0.89
    SES-TEOM = (1 .09 ± 0.07) R&P-2025 +
    (0.21±1.27);R2 = 0.94
    Integrated mass < Continuous PM2.5 mass.
    Difference possibly related to loss of SVOCs and
    N03 from integrated sampler
    Jaques et al. (2004, 166878)69; Hering et al.
    (2004, 155837)109
    Dichot PM25 = 0.83 MOUDI + 1 .23; R2 = 0.83
    . (n = 37)
    Dichot PM2 5 showed higher N03~ loss than MOUDI,
    consistent with anodized aluminum surfaces serving
    as efficient denuders that remove volatilized N03~
    2,110.
    D-TEOM PM2 5 = 1 .1 8 MOUDI - 1 .28; R2 = 0.86
    • (n = 20)
    Over-estimation of D-TEOM may be due to particle
    losses in the MOUDI.
    PM2.5 by D-TEOM during ESP-off phase (net artifact
    • effect) tracked well with the N03 concentrations.
    N03~ vaporization from the TEOM was caused by
    • the temperature of the TEOM filter (-30-50 °C)
    rather than the pressure drop across the filter.
    Vaporization from the TEOM had a time constant
    between 1 0 and 1 00 min depending on ambient and
    TEOM filter temperatures, the vapor pressure, and
    December 2009
    A-26
    

    -------
                    Site / Period / Sampler / Configuration
                                                                       Summary of Findings
    SMPS-3936
                         0.3
                                            Ambient
                                                           None
                                                      Number to
                                                      mass assu-
                                                      ming spherical
                                                      particles of 1.6
                                                      g/cc density
                                  the extent ot vapor saturation upstream and
                                  downstream of the TEOM filter. The mass measured
                                  during 5-min periods (ESP-on and off cycle in D-
                                  TEOM) provides an estimate of the dynamic
                                  vaporization losses.
    
                                  Chakrabarti et al. (2004,1674261111
    
                                  Good agreement between MOUDI PM015 and Nano-
                                  BAM PMois (MOUDI PM0.15 =  0.97 Nano-BAM
                                  PMo.is + 0.60;  R2 = 0.92; n = 24)
    
                                  Nano-BAM captured peak PMo.is concentrations not
                                  quantified by SMPS. Potential particle
                                  agglomeration (with resulting high surface areas)
                                  caused SMPS to include particles in the
                                  accumulation- rather than ultrafine-mode, since
                                  mobility diameter is a function of surface area.
    RUBIDOUX, CA; 08/15/01 to 09/07/01, 07/01/03 to 07/31/03. Rubidoux is located in the eastern
    section of the South Coast Air Basin (SoCAB) in the northwest corner of Riverside County, 78 km
    downwind of the central Los Angeles metropolitan area and in the middle of the remaining agricultural
    production area in SoCAB.
    Sampler
    Flow Rate (L/Min)    Filter Type"
                                                                           Denuded
    PC-BOSS PM2
                         150
                       Teflon (W)
                                                                           GIF
    R&P-2025 PM2.5 FRM   16.7
                       Teflon (N/A)
                                                                           None
    Continuous Sampler   Flow Rate (L/Min)
                       Inlet
                       Temperature
    Dryer
                                                                           Other
    TEOM
                         16.7
                                            50 °C
                                                           None
                                                                           PM2.
    FDMS-TEOM
                         16.7
                                            30 °C
                                                           Nafion
                                                                           PM,
    D-TEOM
                         16.7
                                            30 °C
                                                           Nafion
                                                                           PM2
    RAMS
                         16.7
                                            30 °C
                                                           Nafion
                                                      PM2.5
                                                      Denuders used
    CAMM
                         0.3
                                            N/A
                                                           None
                                                                           PM2
    Radiance Research
    M903
    N/A
                       N/A
                                      Nafion
                                                      bscat
    Radiance Research
    M903
    N/A
                       N/A
                                      None
                                                      bscat
     Grover et al. (2005, 090044)'"' (2003
     measurements):
    
     D-TEOM = (0.98 ± 0.02) FDMS-TEOM +
    - (-0.6 ± 5.3); R2=0.85; n = 426; excludes 38 data
     points when FDMS-TEOM PM2 5 was higher than D-
    - TEOM PM2.5 by -21 ug/m3.
    
    - RAMS = (0.93 ± 0.02) FDMS-TEOM + (2.4 ± 8.2);
     R2 = 0.81; n = 337
    
     FDMS-TEOM = (0.96 ± 0.06) PC-BOSSconstructed
     mass + (-0.3 ± 3.9); R2 = 0.90; n = 33
    
     R&P-2025 FRM = (0.96 ± 0.06)  FDMS-TEOM +
    -(-9.3±3.9);R2 = 0.90;n = 29
    
    - The R&P-2025 FRM PM2.5 was, on avg, -32% lower
     than FDMSTEOM. Losses of NH4N03and organics
    - can account for the difference.
    
     TEOM @ 50 °C PM2 5 was consistently lower than
    - FDMS-TEOM, DTEOM or RAMS and was, on avg,
     - 50% lower than FDMS-TEOM. This difference is
    " due to loss of semi-volatile NOj. and organics from
     the heated TEOM.
    
    - FDMS-TEOM and D-TEOM needed little attention
     from site operators.
    
    - Lee et al. (2005,155925)76 (2001  measurements)
    
     D-TEOM PM2.5 and Radiance Research M903s light
     scattering (with and without dryers) showed good
     correlation.
    
     D-TEOM = (3.69 ± 0.09) Radiance Research
     M903no-dryer + (2.74 ± 0.89); R2 = 0.84; n = 299
    
     D-TEOM = (3.79 ± 0.10) Radiance Research
     M903dryed + (4.08 ± 0.84); R2 = 0.83; n = 312
    
     Radiance Research M903no-dryer = (1.03 ± 0.01)
     Radiance Research M903dryed + (0.34 ± 0.05);
     R  = 0.98; n = 513; absorbed water did not affect
     relationship to PM25
    
     CAMM and RAMS compared poorly (R2 = 0 to 0.25)
     with D-TEOM, Radiance Research M903s and
     among themselves.
    
     RAMS correlated well with D-TEOM for PM2.5
     >30 ug/m due to RAMS's efficient particle collection
     of larger particle sizes (historically associated with
     high mass loadings at this site) in the PM2.5 size
     range.
    
     D-TEOM PM2 5 correlated well with ADI-N sized N03
     (R2 = 0.62) and OC by Sunset OCEC (R2 = 0.61)
     suggesting that  D-TEOM measured PM2.5 mass with
     minimum loss of SVOCs. RAMS showed R2 of 0.20
     (N03~) to 0.30 (OC), while CAMM  showed no
     correlation.
    December 2009
                                             A-27
    

    -------
    Site / Period / Sampler / Configuration
    LINDON, UT; 01/29/03 to 02/12/03
    Sampler
    PC-BOSS PM2.5
    
    CONTINUOUS
    SAMPLER
    TEOM
    FDMS-TEOM
    RAMS
    Flow Rate (L/Min)
    150
    
    FLOW RATE (L/MIN)
    16.7
    16.7
    16.7
    Filter Type3
    Teflon (W)
    
    INLET
    TEMPERATURE
    30 °C
    30 °C
    30 °C
    
    
    
    DRYER
    None
    Nafion
    Nafion
    Denuder"
    GIF
    
    OTHER
    PM2.5
    PM2.5
    PM2.5 Denuder
    used
    PHILADELPHIA, PA; 07/02/01 to 08/01/01 At water treatment center in a grassy field surrounded by
    mixed deciduous and pine trees on three sides and a river on the other. Within 0.5 km of Interstate I-
    95 and within 30 km from downtown Philadelphia.
    Sampler
    Harvard Impactor PM2
    Continuous Sampler
    SES-TEOM
    CAMM
    RAMS
    Radiance Research
    M903
    Radiance Research
    M903
    Flow Rate (L/Min)
    .5 10
    Flow Rate (L/Min)
    16.7
    0.3
    16.7
    N/A
    N/A
    Filter Type3
    Teflon (N/A)
    Inlet Temperature
    35 °C
    N/A
    30 °C
    N/A
    N/A
    
    
    Dryer
    Nafion
    Nafion
    Nafion
    Nafion
    None
    BALTIMORE SUPERSITE, MD; 05/17/01 to 06/11/01. Located near a freeway and
    Sampler
    RAAS-100PM2.5FRM
    Continuous Sampler
    SES-TEOM
    CAMM
    RAMS
    Radiance Research
    M903
    Radiance Research
    M903
    Flow Rate (L/Min)
    16.7
    Flow Rate (L/Min)
    16.7
    0.3
    16.7
    N/A
    N/A
    Filter Type
    Teflon
    Inlet Temperature
    35 °C
    N/A
    30 °C
    N/A
    N/A
    
    
    Dryer
    Nafion
    Nafion
    Nafion
    Nafion
    None
    Denuder1'
    N/A
    Other
    PM2.5
    PM2.5
    PM2.5TEA&
    GIF denude rs
    With particle
    concentrator
    bscat
    bscat
    bus yard.
    Denuder
    None
    Other
    PM2.5
    PM2.5
    PM15TEA&
    CIFdenuders;
    No particle
    bscat
    bscat
    Summary of Findings
    Grover et al. (2005, 090044)66
    RAMS required regular maintenance.
    RAMS = (0.92 ± 0.03) FDMS-TEOM + (1 .3 ± 3.9);
    ' R2 - 0.69; n- 332
    - PC-BOSS constructed mass = (0.89 ± 0.21) FDMS-
    TEOM + (1 .8 ± 2.8); R2 = 0.66; n = 11
    - TEOM @ 30 °C PM2.5 was consistently lower than
    FDMS-TEOM and the difference was consistent
    with concentrations SVOCs and NH4N03 measured
    by PC-BOSS.
    Lee etal. (2005, 128139)73
    Radiance Research M903dryer = (0.78 ± 0.01)
    - Radiance Research M903no dryer + (0.30 + 0.03);
    R2 = 0.95
    Radiance Research M903s vs. CAMM, R2 = 0.78
    Radiance Research M903s vs. RAMS, R2 = 0.63
    Radiance Research M903s vs. SES-TEOM,
    - R2 = 0.72
    CAMM = (0 60 + 0 03) SES-TEOM + (2 0 + 0 42)'
    R2 = 0.71; N = 185
    RAMS = (0.71 ± 0.04) SES-TEOM + (2.51 ± 0.59);
    R2 = 0.63; N = 185
    RAMS = (0.93 ± 0.06) CAMM + (2.44 ± 0.68);
    R2 = 0.55; N = 185
    Both RAMS and CAMM under-measured ambient
    PM2.5.
    CAMM = (0.70 ± 0.06) HI + (0.16 ± 0.96); R2 = 0.87;
    N = 22
    SES-TEOM = (1 .0 ± 0.10) HI + (-0.68 ± 1 .74);
    R2 = 0.89;N = 15
    Lee etal. (2006, 1281 39)73
    Radiance Research M903dryed = (0.65 ± 0.02)
    - Radiance Research M903no dryer + (1 .80 ± 0.20);
    R2 = 0.75, suggesting influence from particle-bound
    water.
    - High correlation (R2 = 0.75) between Radiance
    Research M903s.
    Poor correlation among the continuous instruments.
    Radiance Research M903s did not follow PM2 5
    concentrations measured by other continuous
    instruments.
    CAMM = (0.32 ± 0.07) SES-TEOM + (9.45 ±1.61);
    R2 = 0.14; N = 120
    - RAMS = (0.82 ± 0.10) SES-TEOM + (6.41 ± 2.09);
    R2 = 0.38; N = 120
    RAMS = (0.71 ± 0.12) CAMM + (11 .3 ± 2.23);
    R2 = 0.21; N = 120
    CAMM = (0.80 ±0.29) RAAS-100 FRM +
    (-0.83±5.85);R2=0.60;N = 7
    RAMS = (1 .05 ± 0.12) RAAS-100 FRM +
    (4.80 ± 2.60) ; R2 = 0.90; N = 11
    SES-TEOM = (0.86 ± 0.10) RAAS-100 FRM +
    (2.96±1.99);R2 = 0.90;N = 10
    December 2009
    A-28
    

    -------
    Site / Period / Sampler / Configuration
    SEATTLE, WA; 01/28/01 to 02/21/01
    Urban area near major highway and interstate, 8 km southeast of downtown.
    SAMPLER FLOW RATE (L/MIN) FILTER TYPE3
    MASSPM2.5 16.7 Teflon (N/A)
    Continuous Sampler Flow Rate (L/Min) Inlet Temperature Dryer
    SES-TEOM 16.7 30 °C Nafion
    CAMM 0.3 Ambient Nafion
    RAMS 16.7 30 °C Nafion
    Radiance Research m m Nafjon
    Radiance Research m m None
    
    
    DENUDER"
    Na2C03
    Other
    PM2.5
    PM2.5
    PM2.5TEA&
    GIF denude rs
    bscat
    bscat
    Summary of Findings
    Leeetal. (2006, 166680)108
    Radiance Research M903dryed = 0.94 + 0.00
    Radiance Research M903no dryer; R2 = 1 .0.
    Correlation of Radiance Research M903 vs. SES-
    TEOM R2~080 while that of Radiance Research
    M903 with CAMM was R2 = 0.84 and with RAMS
    CAMM ~ (1 07 + 0 05) RAMS + (1 03 + 0 55)'
    R2 = 0.61
    SES-TEOM = (0.95 ± 0.03) RAMS + (1 .24 ± 0.38);
    R2 = 0.72
    SES-TEOM = (0.87 ± 0.03) CAMM + (0.55 ± 0.37);
    R2 = 0.74
    SES-TEOM likely lost semi-volatile organic matter.
    Continuous PM2 5 samplers were similar to filter
    PM2.5 sampler. Number of samples was small (~7).
    Some SES-TEOM mass values were less than
    MASS filter values suggesting that loss of mass is
    likely for a SES-TEOM at 30°C, particularly during
    the cold season.
    NEW YORK SUPERSITE, NY; 01/01/03 to 12/31/04
    Urban site located at Queens College, NY, about 14 km west of Manhattan, within 2 km of freeways,
    and within 12 km of international airports. A rural site was located at Pinnacle State Park surrounded
    by golf course, picnic areas, undeveloped forest lands, and no major cities within 15 km.
    Sampler
    R&P-2025 PM2.5 FRM
    R&P-2300 PM2.5
    Continuous Sampler
    TEOM
    FDMS-TEOM
    Flow Rate (L/Min)
    16.7
    16.7
    Flow Rate (L/Min)
    16.7
    16.7
    Filter Type3
    Teflon (N/A)
    Teflon (N/A)
    Inlet Temperature
    50 °C
    30 °C
    
    
    
    Dryer
    None
    Nafion
    Denuded
    None
    None
    Other
    PM2.5
    PM2.5
    BAM
                          16.7
                                             "smart" heater on @ RH >44%
             PM2
    Schwab et al. (2006,098449)"'
    
    FDMS-TEOM had operational difficulties resulting in
    low data capture (65% at urban site and 57% at
    rural site).
    
    BAM had data captures greater than 95% at both
    sites.
    
    Urban site:
    
    BAM = (1.02 ± 0.02) FDMS-TEOM + 1.72;
    R2 = 0.93; n = 244
    
    FDMS-TEOM = (1.25 ± 0.02) FRM - (0.63 ± 0.26);
    R2 = 0.95; n = 238
    
    BAM = (1.28 ± 0.03) FRM + (1.27 ± 0.38);
    R2 = 0.88; n = 320
    
    Rural site:
    
    FDMS-TEOM = (1.09 ± 0.02) FRM - (0.004 ± 0.18);
    R2 = 0.95; n = 349
    
    PM2.5 FDMS-TEOM >FRM >TEOM50°C, suggesting
    that FRM captured a fraction, but not all, of the
    volatile components. TEOM50°C volatilizes PM2.5,
    particularly during winter.
    December 2009
    A-29
    

    -------
                          Site / Period / Sampler / Configuration
                                         Summary of Findings
    3Filter Manufacturer in parentheses - W: Whatman, Clifton, NJ; P: Pall-Gelman, Ann Arbor, Ml; S: Schleicher & Schnell. Keene, NH; N/A: not available or not reported.
    bNa2C03: Sodium carbonate; NaHC03: Sodium bicarbonate GIF: Charcoal Impregnated Filter; FEP: Fluorinated Ethylene Propylene copolymer; TEA: Triethanolamine; TSP: Total Suspended PM.
    C37 mm filter.
    d37 mm after-filter for stages smaller than 0.16 urn and 47-mm for higher stages.
    Equivalence requires correlation coefficient (r) Ł 0.97, linear regression slope 1.0 ± 0.05 and an intercept 0 ± 1 ug/m3; Comparability requires r>0.9 and linear regression slope equal 1 within 3 standard errors
    and intercept equal zero within 3 standard errors;  Predictability requires r>0.9. 91,112
    
    
    1Chow (1995, 077012):  2Watson and Chow (2001,157123):3 Watson et al. (1983, 045084): 'Fehsenfeld et al. (2004,157360): 5Solomon et al. (2001,157193): "Watson et al. (2005,157124): 7Mikel (2001,
    1567621: BWatson et al.  (1999, 0209491:9Solomon and Sioutas (2006,1569951:10Graney et al. (2004, 0537561: "Tanaka et al. (1998,1570411:12Pancras et al. (2005, 0981201: "John et al. (1988, 0459031:
    "Hering and Cass (1999, 0849581:15Fitz et al. (1989, 0773871:1BHering et al. (1988, 0360121: "Solomon et al. (2003,1569941:1BCabada et al. (2004,1488591: "Fine et al. (2003,1557751:20Hogrefe et al.
    (2004, 099003): 21Drewnick et al. (2003, 099160): 22Watson  et al. (2005,157125): 23Ho et al. (2006,156552): 2
    -------
    Table A-12.    Summary of element and liquid water content measurement comparisons.
                 SITE/PERIOD/SAMPLER
                              SUMMARY OF FINDINGS
    College Park, MD; 11/18/1999 to 11/19/1999,11/22/1999
    
    Adjacent to a parking lot in the University of Maryland
    campus, influenced by motor vehicles, coal-fired power plants
    and incinerators ~21 km southwest of site and regionally
    transported material.
    
    Concentrated Slurry/Graphite Furnace Atomic Absorption
    Spectrometry (GFAAS) (collectively known as Semi-
    Continuous Elements in Aerosol Sampler, SEAS)
    
    Ambient air is pulled in at a flow rate of 170 L/min. Particles
    are grown using steam injection to about 3 to 4 urn in
    diameter, which are then concentrated and separated from
    the air stream in the form of a slurry using impactors. The
    slurry is collected in glass sample vials, which are
    subsequently analyzed by GFAAS in the laboratory.
    Kidwell and Ondov (2001, 017092: 2004,166898)
    
    Overall collection efficiency (of the entire system) measured using latex particles was 40%
    for particles initially 0.1 to 0.5 urn in diameter, increasing with size to 68% for particles 3 urn
    in diameter. Major losses were in the virtual impactor major flow channel and in the
    condensers.
    
    Six elements were detected simultaneously, limited by spectral interference and the
    minimum detectable limit (MDL). Twelve elements (Al, Cr, Mn, Fe, Ni, Cu,Zn,As, Se,Cd,
    Sb, and Pb) were measured.
    
    MDLs ranged from 3.2 picogram (pg = 10~12 gram) to 440 pg.
    
    Comparison with NIST standards showed good agreement, except for Al, Grand Fe, due to
    poor atomization. The method was valid for dissolved solutions, but not for large  particles
    (>10um).
    
    Overall avg relative standard deviation (RSD) was 20 to 43% by error propagation, mainly
    due to the collection and analytical efficiencies.
    
    There were possible memory effects due to particle adhesion to impactor collection
    surfaces.
    
    Lower MDLs may be possible through redesign and introduction of a wash cycle  between
    samples. A2.5 urn inlet might improve analytical efficiency by removing coarse particles.
    Pittsburgh Supersite, PA; 08/26/2002 to 09/02/2002
    
    6 km east of downtown in a park on the top of a hill.
    
    Laser Induced Breakdown Spectroscopy (LIBS)
    
    Ambient air was concentrated using a PM2.s inlet and a virtual
    impactor. The concentrated stream was transported through a
    Teflon tube to the sample cell of the LIBS system. The sample
    cell was excited using a Nd: YAG laser. The resulting plasma
    was collected and focused into a spectrometer, generating
    spectra characteristic of different elements.
    Lithgow et al. (2004,126616)
    
    Calibration was done by sampling particle-laden streams with known metal concentrations.
    Good linear fits with correlation coefficients 0.97 to 0.99
    
    Seven metals (Na, Mg, Al, Ca, Cr, Mn, and Cu) were analyzed.
    
    The MDLs were in the order of femtograms (fg = 10~15 gram) per sample.
    
    This system has the capability of identifying the components, quantifying them and also
    giving a particle size distribution. Mass was underestimated because of missing small
    particles.
    Pittsburgh Supersite, PA; 07/01/2001 to 08/31/2001,
    01/01/2002 to 07/01/2002.
    
    6 km east of downtown in a park on the top of a hill.
    
    Dry Ambient Aerosol Size Spectrometer (DAASS)
    
    Measures the aerosol size distribution (using nano-SMPS,
    SMPS and APS) alternatively, at ambient relative humidity
    (RH) (ambient channel) and at low RH (18 ± 6%) (dry
    channel). A comparison of the two size distributions provides
    information on the water absorption and change in size due to
    RH.
    Stanier et al. (2004,096966): Khlystov et al. (2006,166636)
    
    Measured water content ranging from less than 1 ug/m3 to 30 ug/m3, constituting < 5% to
    100% of the dry aerosol mass.
    
    Small differences between dry and ambient channels of the DAASS. Number concentrations
    were within 5% of each other.
    
    Additional sources of error are associated with temperature differences between measured
    outdoor ambient temperature and the temperature at which the ambient measurement
    channel was maintained. Although the measurement system was placed in a ventilated
    enclosure, it was ~4 °C higher than ambient temperature during July 2001. During winter,
    the system was maintained at a minimum temperature of 9 °C, while the outdoor
    temperature dropped to -5 °C. This caused differences in RH sensed by the system in the
    ambient  channel versus the actual outdoor RH.
    
    RH differences cause underestimation of the particle number at sizes < 200 nm and an
    overestimation at sizes >200 nm. This causes the volume growth factor to be higher by 2 to
    14%, with the highest bias occurring  at high RH and low temperature (92% outside RH and -
    5°C).
    
    The difference in temperature might also lead to evaporation of semi-volatile components
    such as NH4N03. For the winter period, it was estimated that, for the worst case, the volume
    growth factor would be underestimated by about 10% for 60-90% RH.
    
    Insufficient purging of dry air between the dry and ambient cycles (implying the need for
    supplemental vacuum  power during the vent stages) causes uncertainties in estimated
    growth factors. Correction factors were between 0.97 and 1.03.
    
    Water content estimated by DAASS can  be used to evaluate the thermodynamic models.
    For the Pittsburgh study, the models  underestimated the water content by 37%.
    
    Data from DAASS showed that the aerosol was wet even at ambient RH less than 30%.
                                                                                                          Source: Chow et al. (2008,1563551
    December 2009
              A-31
    

    -------
    Table A-13. Summary of PM2.6 N03" measurement
    comparisons.
    SITE / PERIOD / SAMPLER / CON FIGURATION
    ATLANTA SUPERSITE, GA: 8/3/99 to 9/1/99 Four km NW of downtown, within 200 m of a bus
    maintenance yard and several warehouse facilities, representative of a mixed commercial-residential
    neighborhood.
    Sampler
    R&P-2000 FRM
    RAAS-400
    SASS
    MASS-400
    MASS-450
    R&P-2300
    VAPS
    URG-PCM
    ARA-PCM
    PC-BOSS (TVA)
    PC-BOSS (BYU)
    PC-BOSS (BYU)
    MOUDI-100
    Continuous Sampler
    ADI-N
    ARA-N
    PILS-IC
    ECN
    TT
    Flow Rate (L/Min)
    16.7
    24
    6.7
    16.7
    16.7
    10
    15
    16.7
    16.7
    105
    150
    150
    30
    Flow Rate (L/Min)
    1
    3
    5
    16.7
    5
    Filter Type3
    Quartz (P)
    Nylon (P)
    Nylon (P)
    Teflon (P)-Nylon (P
    Quartz (P)
    Nylon (P)
    Polycarbonatec (front &
    back-up)
    Teflon (P)-Cellulose-fiber
    (W
    Teflon (N/A)-Nylon (N/A)
    Teflon (W)-
    Nylon (P)
    Teflon (W)-
    Nylon (P)
    Quartz (P)-
    CIF (S)
    Teflon (N/A-
    Quartz (N/A
    Denuder1'
    None
    MgO
    MgO
    Na2C03
    None
    Na2C03
    Na2C03
    Na2C03
    Na2C03/Citric acid
    GIF
    GIF
    GIF
    None
    Denuder Analysis Method1'
    Activated Carbon NOX
    Potassium iodide
    (Kl) and dual sodium NOX
    chlorite (NaCI02)
    Two URG annular
    glass denuders in
    series containing 1C
    citric acid and
    CaC03
    Rotating annular wet ,c
    denuder system
    Wet parallel plate ,„
    denuder
    Chemiluminescence
    Chemiluminescence
    
    
    
    
    SUMMARY OF FINDINGS
    Solomon et al.(2003, 166994) 1T
    PM25 N03" from each sampler was compared to
    reference (filter RR) value. Overall agreements
    
    due to volatilized N03", differences in denuder
    design and filter types, and low concentrations
    (close to analytical uncertainty).
    A small positive artifact (few tenths of ug/m3) might
    be present when using Na2
    C03 impregnated filters, due to possible collection
    (and subsequent oxidation) of MONO and N02 on
    carbonate-impregnated filters. In addition, glycerol
    in Na2C03 coated denuders may contaminate the
    filters downstream.
    PM15 N03- R&P-2000 FRM and MOUDI-100
    samplers are consistently lower than other
    samplers.
    Weber etal. (2003, 157129)82
    Hourly PM2.5 N03-were compared to all-sampler
    averages (continuous RR), similar to the approach
    used for integrated filter samplers. Overall
    agreements were within + 20-30% (or + 0.2 ug/m )
    except for ARA-N.
    Except for ARA-N, good correlations (R2= 0.70 to
    0.90) were found during the second half of the
    study. The poor performance of ARA-N was
    probably due to an inefficient denuder (25-60%
    efficient) resulting in high background.
    Large discrepancies between continuous and filter
    RR probably due to low ambient concentrations
    (study avg = 0.5 ug/m3) near the detection limit
    (-0.1 ug/m3, except for ARA-N, which had
    0.5 ug/m3).
    The ARA-N was within 13%, ADI-N, ECN and
    PILS-IC within 1 8% and TT within 26% of filter RR
    (all<0.2 ug/m3 difference).
    Filter samples showed more variability (Relative
    Standard Deviation, RSD = 22%) than continuous
    measurements (RSD = 13%). This is probably due
    to sampling artifacts in filter samples; N03-
    be minimal due to shorter averaging times and
    rapid stabilization in solutions.
    December 2009
    A-32
    

    -------
                       SITE / PERIOD / SAMPLER / CON FIGURATION
                                                                           SUMMARY OF FINDINGS
    PITTSBURGH SUPERSITE, PA; 7/1/01 to 8/1/02 6km east of downtown in a park on the top of a I
    Sampler
    Flow Rate (L/Min)    Filter Type"
                                                               Denuder"
    MOUDI-110
                          30
                       Teflon (W)
                       Teflon (W)
                                                                None
    CMU
                          16.7
                                             Nylon (W)
                                         MgO/Citric acid
    R&P-2000 FRM
                          16.7
                                             Teflon (W)
                                                               None
     Cabada et al. (2004,148869)  ; Takahama et al.
    - (2004,1670381116
    
    - More than 70% (-0.5 ug/m3) of N03 mass was lost
     from MOUDI samplers during summer.
    
    - MOUDI N03 = 0.27 CMU; R2 =  0.40; Summer
     MOUDI N03 = 0.99 CMU; R2 =  0.49; winter
    
    ' Wittigetal. (2004,103413f
    
     Avg conversion efficiency to NOX (tested using
     NH4N03 solution) was 0.85 ± 0.08. Gas analyzer
     efficiency was stable at 0.99 ±  0.04.
    
     Corrections were made for instrument offset,
     software calculation error, conversion efficiency,
     gas analyzer efficiency, vacuum drift, and sample
     flow drift. The overall avg correction was 8%,
     ranging from-62% to 93%.
    
     Data Recovery >80%. Data loss was associated
     with vacuum pump failures and excessive flash
     strip breakage.
                                                                                         R&P-8400N = 0.83 CMU
                                                                                       -0.20 ug/m3; R2= 0.84
                                                                                         Underestimation in the R&P-8400N could be due
                                                                                         to incomplete particle collection or incomplete
                                                                                         conversion of various forms of N03".
    
                                                                                         Used co-located filter measurements for final
                                                                                         calibration.
    FRESNO SUPERSITE, CA and other CRPAQS sites; 12/2/99 to 2/3/01
    Located 5.5 km northeast of downtown in a mixed residential-commercial neighborhood. 107
    Sampler
    DRI-SFS
    RAAS-400
    RAAS-400
    RAAS-100 FRM
    Continuous Sampler
    R&P-8400N
    Sampler
    PC-BOSS
    Continuous Sampler
    R&P-8400N
    Dionex-IC
    Flow Rate (L/Min)
    113
    24
    24
    16.7
    Flow Rate (L/Min)
    5
    Flow Rate (L/Min)
    150
    Flow Rate (L/Min)
    5
    5
    Filter Type3
    Quartz (Pellulose
    Quartz (P)-Nylon (P)
    Quartz (P)-Quartz (P)
    Quartz (P)
    Denuder
    Activated Carbon
    Filter Type3
    Teflon (W)- Nylon (P)
    Denuder
    Activated Carbon
    Parallel plate wet denuder
    Denuder11
    AI203
    Na2C03
    None
    None
    Analysis Method"
    NOx
    Chemiluminescence
    Denuder11
    GIF
    Analysis Method"
    NOx
    Chemiluminescence
    1C
    Chow et al. (2005, 099030)87
    Maximum N03- volatilization was observed during
    summer (Jun-Aug), while the lowest volatilization
    was observed during winter (Dec-Feb).
    Seasonal avg volatilized N03- in particulate N03"
    (PN03 , the sum of non-volatilized and volatilized
    N03") ranged from less than 10% during winter to
    more than 80% during summer.
    Volatilized NH4N03 accounted for 44% of actual
    PM2s mass (i.e., measured mass plus volatilized
    NH4N03) in Fresno during summer.
    Front-quartz non-volatilized N03- concentrations
    were similar for DRISFS (0.52 ± 0.26 ug/m3) and
    RAAS-100 FRM (0.81 +0.33 ug/m3) for warm
    months (May-Sep). With preceding denuders, the
    DRI-SFS PN03 concentration (3 + 19 ug/m3) was
    much higher than the RAAS100 FRM N03",
    gaseous nitric acid (HN03) resulting in N03-
    volatilization. FRM Teflon-membrane filters are
    subject to similar N03 losses.
    Chow et al. (2005, 1 66348)
    December  2009
                                           A-33
    

    -------
                       SITE / PERIOD / SAMPLER / CON FIGURATION
                                    SUMMARY OF FINDINGS
                                                                                         High correlation (R >0.90) between 24-h avg
                                                                                         R&P-8400N N03 and SFS filter N03"
                                                                                         concentrations, but R&P-8400N N03- was 7 to
                                                                                         25% lower than filter N03,
    
                                                                                         Limited comparison (n < 15) with filter samples at
                                                                                         Bakersfield showed that the slopes were close to
                                                                                         unity during early morning hours, while they
                                                                                         decreased during the afternoon hours, indicating
                                                                                         possible loss of N03" by the R&P-8400N
                                                                                         instrument.
    
                                                                                         The R&P-8400N required substantial maintenance
                                                                                         and careful operation.
    
                                                                                         Grover et al. (2006,138080165
    
                                                                                         Dionex-IC N03 = (0.71 ± 0.04) PC-BOSS N03 +
                                                                                         (3.2±1.1);R2 = 0.91;n = 29
    
                                                                                         R&P-8400N = (1.10 ± 0.06) PC-BOSS N03 -
                                                                                         (0.8±1.8);R2 = 0.93;n = 29
    
                                                                                         R&P-8400N = (0.55 ± 0.01) Dionex-IC +
                                                                                         (1.4±1.8);R2 = 0.75;n = 493
    
                                                                                         R&P-8400N measured less than Dionex-IC,
                                                                                         particularly at high RH. R&P-8400N may suffer
                                                                                         incomplete flash vaporization under conditions of
                                                                                         high RH.
    December  2009
    A-34
    

    -------
                        SITE / PERIOD / SAMPLER / CON FIGURATION
                                                                              SUMMARY OF FINDINGS
    BALTIMORE SUPERSITE, MD; 2/14/02 to 11/30/02
    Adjacent to a parking lot in the University of Maryland campus, influenced by motor vehicles, coal-fired
    power plants and incinerators -21 km southwest of site and regionally transported material.
    Sampler
    Flow Rate (L/Min)    Filter Type3
                                                                       Denuder
    SASS
                           6.7
                                               Nylon (N/A)
                                                MgO
    Continuous Sampler    Flow Rate (L/Min)    Denuder
                                                Analysis Method"
    R&P-8400N
                                               Activated Carbon
                                                NOx
                                                Chemiluminescence
                                           Harrison et al. (2004,136787) °J
    
                                           Corrections were made to R&P-8400N data for
                                         . software calculation error, conversion efficiency,
                                           gas analyzer efficiency, vacuum drift and sample
                                         - flow drift.
    
                                         - The relative uncertainty of R&P-8400N
                                           measurements averaged 8.7%, ranging from 6.3%
                                         - to 23%.
                                                                                             Data capture >95%.
                                                                                                                                  -by
                                                                     R&P-8400N underestimated SASS filter N03'
                                                                     -33%, attributed to variations in conversion
                                                                     efficiency, matrix effects, and impaction efficiency.
                                                                     This suggested a true conversion efficiency of
                                                                     68% as compared to an avg conversion efficiency
                                                                     of R&P-8400N to NOX (tested using potassium
                                                                     nitrate solution) of 0.90 ± 0.04.
    
                                                                     Large errors occurred when the concentrations
                                                                     were near the detection limit, when the
                                                                     temperature difference (between instrument and
                                                                     ambient) was large, and when the ambientRH was
                                                                     < 40%. Ridged flash strips produced lower
                                                                     dissociation losses than flat strips.
    
                                                                     Reliable measurements were obtained when the
                                                                     instrument-outdoor temperature differences were
                                                                     minimal and when grooved/ridged flash strips were
                                                                     used. A co-located filter measurement was used
                                                                     for final corrections.
    NEW YORK SUPERSITE, NY; 06/29/01 to 08/05/01 and 07/09/02 to 08/07/02
    Urban site located at Queens College, NY, about 14 km west of Manhattan, within 2 km of freeways,
    and within 12 km of international airports. Rural site located at Whiteface mountain, 600 m above sea
    level, in a clearing surrounded by deciduous and evergreen trees and no major cities within 20 km of
                                                                     Hocirefeetal. (2004.099003)-°
    
                                                                     Data completeness: 86-88% for R&P-8400N, 94 -
                                                                     98% for AMS, and 65-70% for PILS-IC.
    me sue.
    Sampler
    R&P-2300
    Continuous Sampler
    R&P-8400N
    PILS-IC
    AMS
    
    Flow Rate (L/Min)
    10
    Flow Rate (L/Min)
    5
    5
    0.1
    
    Filter Type3
    Nylon (N/A)
    Denuder
    Activated Carbon
    Na2C03and citric
    acid
    None
    
    Denuder"
    Na2C03
    Analysis Method"
    NOx Chemiluminescence
    1C
    Mass Spectrometry
    Some PILS measurements were invalidated owing
    to larger aqueous flow caused by bigger tubing.
    Larger aqueous flow and inconsistent water quality
    affected N03~ concentrations.
    R&P-8400N NOs. was lower than R&P-2300 filter
    - N03~ PILS-IC was within 5% of R&P-2300 filter
    NOs. concentrations.
    At the urban site, AMS was within 10% of the filter
    N03 concentration. At the rural site, AMS had a
    NOs"
    NEW YORK SUPERSITE, NY; 10/01 to 07/05 (urban), 07/02 to 07/05 (rural) Urban site located at a
    school in South Bronx, NY in a residential area, within a few kilometers away from major highways and
    a freight yard (experiencing significant truck traffic). Rural site located at Whiteface mountain, 600 m
    above sea level, in a clearing surrounded by deciduous and evergreen trees and no major cities within
    20 km of the site.
    Sampler
    R&P-2300
    TEOM-ACCU
    Continuous Sampler
    Flow Rate (L/Min)
    10
    16.7
    Flow Rate (L/Min)
    Filter Type3
    Nylon (N/A)
    Zefluor
    Denuder
    Denuder"
    Na2C03
    None
    Analysis Method"
    R&P-8400N
                                                 Activated Carbon   NOX Chemiluminescence
                                                                     Rattigan et al. (2006,116897)"
    
                                                                     Data capture was more than 94%.
    
                                                                     Data were adjusted for span and zero drifts,
                                                                     conversion efficiency, flow drift, and blanks.
    
                                                                     R&P-8400N NOs'was systematically lower than
                                                                     R&P-2300 filter N03over all concentration ranges,
                                                                     except at <1 ug/m .
    
                                                                     Urban: R&P-8400N = 0.59 R&P-2300 N03 + 0.28;
                                                                     R2 = 0.88; n = 305
    
                                                                    " Rural: R&P-8400N = 0.73 R&P-2300 N03+ 0.01;
                                                                     R2 = 0.90; n~161; however concentrations were
                                                                     low with 95% of data < 1 ug/m3
    
                                                                     Required weekly or biweekly maintenance by
                                                                     trained personnel.
    LOS ANGELES SUPERSITE, CA; 7/13/01 to 9/15/01 (Rubidoux) and 9/15/01 to 2/10/02
    (Claremont)
    Multiple sampling locations in the South Coast Air Basin (SoCAB), including urban "source" sites and
    downwind "receptor" sites.
                                                                     Fine etal. (2003,155775)19
    
                                                                     MOUDI = 0.68 HEADS; R2 = 0.88
    
                                                                    . ADI-N Sized = 0.80 HEADS; R2 = 0.79
    Sampler
    Flow Rate (L/Min)
    Filter Type3       Denuder"
    December 2009
                                            A-35
    

    -------
                        SITE / PERIOD / SAMPLER / CON FIGURATION
                                       SUMMARY OF FINDINGS
    MOUDI
                           30
                                                     Teflon (P)
                                                                       None
    HEADS
                           10
                                                     Teflon (N/A)-GF-  Carbona(e
    Continuous Sampler     Flow Rate (L/Min)    Denuder
    Analysis Method"
    ADI-N Sized
                           0.9
                                              Activated Carbon    NOX Chemiluminescence
     ADI-N Sized = 1.12 MOUDI; FT = 0.53
    
     ADI-N NOs- showed better agreement with HEADS
     at lower concentrations, the ADI-N deviated
    - (biased low) from the HEADS concentrations at
     higher N03 concentrations. This deviation was
    - attributed to N03.vaporization, loss of N03~
     associated with particles less than 0.1 urn not
    " collected by the ADI-N sampler, or loss of particles
     in the ADI-N inlet tubing.
    
     The underestimation of N03. by MOUDI compared
     to HEADS may be due to N03~volatilization from
     MOUDI stages, since S042~ comparisons showed
     MOUDI to explain 85% of HEADS S042~
    
     ADI-N and  MOUDI showed better correlation
     (R2 = 0.67) for the 1 -2 urn size range N03 relative
     to other size ranges (R2< = 0.56). This is possibly
     due to N03  in the form of non-volatilized  sodium
     nitrate (NaN03) than volatilized NH4N03in the 1-
     2 urn size range. Single particle analysis  also
     indicated this possibility of NaN03 in the 1-2 urn
     range.
    RUBIDOUX, CA; 07/01/03 to 07/31/03
    Located in the eastern section of SoCAB in the northwest corner of Riverside County, 78 km downwind
    of the central Los Angeles metropolitan area and in the middle of the remaining agricultural production
    area in  SoCAB.
                              Grover et al. (2005,090044)'"'
    
                              R&P-8400N = (0.65 ± 0.07) PC-BOSS +
                              (3.3±2.4);R2 = 0.73;n = 31
    
                              At higher concentrations (no numerical value
                              reported), R&P-8400N N03-was lower than PC-
                              BOSS N03., possibly due to incomplete
                              volatilization of NH4N03in R&P-8400N at higher
                              concentrations (and higher relative humidity).
    
                              At the urban site, the continuous instruments
                              correlated well with filter N03~. measurements and
                              among themselves (R2> 0.89). At the rural site, R2
                              ranged from 0.61 to 0.83, except for the AMS
                              versus R&P2300 comparison, with an R2 of 0.46.
    Sampler
    PC-BOSS
    Continuous Sampler
    R&P-8400N
    R&P-8400N
    PILS-IC
    AMS
    Flow Rate (L/Min)
    150
    Flow Rate (L/Min)
    5
    5
    5
    0.1
    Filter Type3
    Teflon (W)-Nylon (P)
    Denuder
    Activated Carbon
    Activated Carbon
    Na2C03 and Citric acid
    None
    Denuder1'
    GIF
    Analysis Method'1
    NOX Chemiluminescence
    NOX Chemiluminescence
    1C
    Mass Spectrometry
    December 2009
      A-36
    

    -------
                               SITE / PERIOD / SAMPLER / CON FIGURATION
                                                 SUMMARY OF FINDINGS
    3Filter Manufacturer in parenthesis - W: Whatman, Clifton, NJ; P: Pall-Gelman, Ann Arbor, Ml; S: Schleicher & Schnell. Keene, NH; N/A: not available or not reported.
    bAI203: Aluminum oxide; GF: Na2C03 impregnated Glass Fiber Filters; 1C: Ion chromatography; MgO: Magnesium oxide; Na2C03: Sodium carbonate; NaHC03: Sodium bicarbonate NOX: Oxides of nitrogen;
    GIF: Charcoal Impregnated Filter; FEP: Fluorinated Ethylene Propylene copolymer; TEA: Triethanolamine; TSP: Total Suspended PM.
    cNa2C03 impregnated.
    d37 mm filter.
    
    
    1Chow (1995, 077012): 2Watson and Chow (2001,1571231:3 Watson et al. (1983, 045084): 4Fehsenfeld et al. (2004,1573601:5Solomon et al. (2001,1571931: BWatson et al. (2005,1571241:7Mikel (2001,
    156762): "Watson et al. (1999, 020949): 'Solomon and Sioutas (2006,156995): 10Graney et al.  (2004, 053756): "Tanaka et al. (1998,157041): 12Pancras et al. (2005, 098120): "John et al. (1988, 045903):
    "Hering and Cass (1999, 0849581:15Fitz et al. (1989, 0773871:1BHering et al. (1988, 0360121: "Solomon et al. (2003,1569941:1BCabada et al. (2004,1488591: "Fine et al. (2003,1557751:2DHogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 0991601:22Watson et al. (2005,1571251:23Ho et al. (2006,1565521:24Decesari et al. (2005,1445361:25 Mayol-Bracero et al. (2002, 0450101:26Yang et al. (2003,
    156167): 27Tursic et al. (2006,157063): 2BMader et al.(2004,156724): 28Xiao and Liu (2004, 056801): 30Kiss et al. (2002,156646): 31Cornell and Jickells (1999,156367):32 Zheng et al. (2002, 026100):
    33Fraser et al. (2002,1407411: x Fraser et al. (2003, 042231135Schauer er al. (2000, 0122251:3BFine et al. (2004,1412831:37Yue et al. (2004,1571691:3BRinehart et al. (2006,1151841:39Wan and Yu (2006,
    1571041: "Poore (2000, 0128391:41Fraser et al. (2003, 0402661:42Engling et al. (2006,1564221:43Yu et al. (2005,1571671:44Tran et al. (2000, 0130251:45Yao et al. (2004,1022131:4BLi and Yu (2005,
    156692): "Henning et al. (2003,156539): 4BZhang and Anastasio (2003,157182): "Emmenegger et al. (2007,156418):50 Watson et al, (1989,157119): 51Greaves et al. (1985,156494): 52Waterman et al.
    (2000,1571161:53Waterman et al. (2001,1571171: aFalkovich and Rudich (2001,1564271:55Chow et al. (2007,1572091:5BMiguel et al. (2004,1232601:57Crimmins and Baker (2006, 0970081:5BHo and Yu
    (2004,1565511:58Jeon et al. (2001, 0166361: BOMazzoleni et al. (2007, 0980381: B1Poore (2002, 0514441: B2Butler et al. (2003,1563131: B3Chow et al. (2006,1466221: MRussell et al. (2004, 0824531: B5Grover
    et al. (2006,138080): BBGrover et al. (2005, 090044): B7Schwab et al. (2006, 098449): BBHauck et al. (2004,156525): B8Jaques et al. (2004,155878): 70Rupprecht and Patashnick (2003,157207): 71Pang et al
    (2002, 0303531:72Eatough et al. (2001, 0103031:73Lee et al. (2005,128139); MLee et al. (2005,1566801:75Babich et al. (2000,1562391:7BLee et al. (2005,1559251:77Lee et al. (2005,1281391:7BAnderson
    and Ogren (1998,1562131:79Chung et al. (2001,1563571: BOKidwell and Ondov (2004,1558981: B1Lithgow et al. (2004,1266161: B2Weber et al. (2003,1571291: B3Harrison et al. (2004,1367871: "Rattigan et
    al. (2006,115897): B5Wittig et al. (2004,103413): BBVaughn et al. (2005,157089): B7Chow et al. (2005, 099030): BBWeber et al (2001, 024640); B8Schwab et al. (2006, 098785): ™Lim et al. (2003, 037037):
    "Watson and Chow (2002, 0378731:82Venkatachari et al. (2006,1059181:83Bae et al. (2004,1562431:84Arhami et al. (2006,1562241:85Park et al. (2005,1568431:8BBae et al. (2004, 0986801:87Chow et al.
    (2006,1563501:8BArnott et al. (2005,1562271:88Bond et al. (1999,1562811:1DDVirkkula et al. (2005,1570971:1D1Petzold et al. (2002,1568631:102Park et al. (2006, 0981041:103Arnott et al. (1999, 0206501:
    "Veters et al. (2001, 016925): 105Pitchford et al. (1997,156872): 10BRees et al. (2004, 097164): 107Watson et al. (2000, 010354): 10BLee et al. (2005,156680): 108Hering et al. (2004,155837): ™Watson et al.
    (1998,1988051: '"Chakrabarti et al. (2004,1574261:112Mathai et al. (1990,1567411: '"Kidwell  and Ondov (2001.0170921: '"stanier et al. (2004, 0959551: '"Khlystovet al. (2005,1566351:11BTakahama et
    al. (2004,1570381:117Chow et al. (2005,1563481: '"Zhang et al. (2002,1571811: '"Subramanian et al. (2004, 0812031:120Chow et al. (2006,1552071: ™Birch and Cary (1996, 0260041:122Birch (1998,
    024953): 123Birch and Cary (1996, 002352): ™NIOSH (1996, 156810): 125NIOSH (1999,  156811): 12BChow et al. (1993, 077459): 127Chow et al. (2007, 156354): ™Ellis and  Novakov (1982, 156416):
    128Peterson and Richards (2002,1568611:130Schauer et al. (2003,  0370141: "iMiddlebrook et al. (2003, 0429321: "2Wenzel et al. (2003,1571391: "3Jimenez et al. (2003,1566111: "Vhares et al. (2003,
    1568661:135Qin and Prather (2006,1568951:  "BZhang et al. (2005,1571851:137Bein et al. (2005,1562651: "BDrewnick et al. (2004,1557541: "8Drewnick et al. (2004,1557551: "°Lake et al. (2003,1566691:
    "'Lake etal. (2004, 088411)
    
    
                                                                                                                                                Source: Chow etal. (2008,156355)
    December  2009
    A-37
    

    -------
    Table A-14. Summary of PM2.6 S042" measurement comparisons
    SITE/PERIOD/SAMPLER/CONFIGURATION
    ATLANTA SUPERSITE, GA: 08/03/99 to 09/01/99
    Four km NW of downtown, within 200 m of a bus maintenance yard and several warehouse facilities,
    representative of a mixed commercial-residential neighborhood.
    Sampler
    R&P-2000 FRM
    RAAS-400
    SASS
    MASS-450
    R&P-2300
    VAPS
    URG-PCM
    ARA-PCM
    ARA-PCM
    PC-BOSS (TVA)
    PC-BOSS (TVA)
    PC-BOSS (BYU)
    PC-BOSS (BYU)
    MOUDI-100
    Continuous Sampler
    ADI-S
    PILS-IC
    ECN
    TT
    PITTSBURGH SUPERSITE
    6 km east of downtown in a
    Sampler
    MOUDI-110
    CMU
    Flow Rate (L/Min)
    16.7
    24
    6.7
    16.7
    10
    15
    16.7
    16.7
    16.7
    105
    105
    150
    150
    30
    Flow Rate (L/Min)
    2.7
    5
    16.7
    5
    , PA; 070/1/01 to 08/01/02
    park on the top of a hill
    Flow Rate (L/Min)
    30
    16.7
    Filter Type3
    Quartz (P)
    Teflon (P)
    Teflon (P)
    Quartz (P)
    Quartz (P)
    Quartz (P)
    Teflon (P)-Cellulose-fiber
    (W)
    Teflon (N/A)
    Nylon (N/A)
    Teflon (W)
    Quartz (P)
    Teflon (W)
    Quartz (P)
    Teflon (N/A)
    Quartz (N/A)
    Denuder
    Activated Carbon
    Two URG annular glass
    denuders in series
    containing citric acid &
    CaC03
    Rotating annular wet
    denuder system
    Wet parallel plate
    denuder
    
    Filter Type3
    Teflon (W)
    Teflon (W)
    Denuder"
    None
    None
    None
    None
    None
    XAD-4
    
    Na2C03/Citric acid
    Na2C03/Citric acid
    GIF
    GIF
    GIF
    GIF
    None
    Analysis Method"
    S02, UV
    Fluorescence
    1C
    1C
    1C
    
    Denuder11
    None
    MgO/Citric acid
    SUMMARY OF FINDINGS
    Solomon et al. (2003, 166994) 1T
    PM2 5 S042~ from each sampler was
    compared to all-sampler averages, called the
    filter relative reference (filter RR) value. The
    samplers agreed to within 10% of filter RR,
    except for the PC-BOSS (TVA) and MOUDI-
    100.
    While avg mass was within 10%, daily
    
    correlated well (R2 >0.90) with daily filter RR.
    PC-BOSS (TVA) had instrument leaks.
    The R&P-2000 FRM, on avg, agreed within
    1% of filter RR.
    MOUDI-100 was -13% low compared to filter
    RR
    Weber etal (2003 1 571 29)82i Zhang etal
    (2002, 167181)118 '
    Hourly PM2.5 S042~ were compared to all-
    the approach used for filter samplers . Overall
    agreement was within 16% or 2 ug/m
    Good correlations (R - 0.76 to 0.94) were
    found during the second half of the study,
    except for TT versus ADI.
    Good correlation (R2 = 0.84) was found
    between continuous and filter-based S042
    Continuous RR = (1 .15 ± 0.15), Filter RR +
    (0.41 ±1.73)
    Variability among continuous S042~
    instruments (RSD = 13%) was similar to that
    for NOs. instruments. Filter sample variability
    was low (RSD - 8%) indicating more
    uniformity among samplers.
    The ECN and TT instruments were within
    15%, PILS-IC was within 20% and ADI-S was
    within 26% of filter RR.
    Cabadaetal. (2004, 148859)18; Takahama
    etal. (2004,157038)™
    MOUDI S042' 0.80 CMU; R2 = 0.95; Summer
    MOUDI S042" 0.97 CMU; R2 = 0.48; winter
    Wittig et al. (2004, 103413)85
    December 2009
    A-38
    

    -------
                            SITE/PERIOD/SAMPLER/CONFIGURATION
                                                                             SUMMARY OF FINDINGS
    R&P-2000 FRM
                              16.7
                                                      Teflon (W)
                                                                             None
    Continuous Sampler
    Flow Rate
    (L/Min)
                                               Denuder
                        Analysis Method"
    R&P-8400S
                                               Activated Carbon      S02 UV Fluorescence
     Avg conversion efficiency to S02 (tested
    - using ammonium sulfate [(NH4)2S04]
     solution) was 0.65 ± 0.07. Gas analyzer
    - efficiency was stable at 0.99 ± 0.06.
    
     Corrections were made for instrument offset,
    - software calculation error, conversion
     efficiency, gas analyzer efficiency, vacuum
     drift, and sample flow drift. The overall
     correction was, on avg, -1 % and ranged from
     -90% to 100% for individual samples.
    
     Data Recovery >90%. Data loss was
     associated with vacuum pump failures or
     excessive flash strip breakage.
    
     R&P-8400S (S042~) = 0.71 CMU +
     0.42 ug/m3; R2 = 0.83
    
     Underestimation is  attributed to incomplete
     particle collection or incomplete conversion of
     various forms of S042~.
    
     Used co-located filter measurements for final
     calibration.
    LOS ANGELES SUPERSITE, CA; 07/13/01 to 09/15/01 (Rubidoux) and 09/15/01 to 02/10/02
    (Claremont)
    Multiple sampling locations in the South Coast Air Basin (SoCAB), including urban "source" sites and
    downwind "receptor" sites.
                                                                       Fine et al. (2003,166776)19
    
                                                                       MOUDI explained 85% of HEADS S04:
                                                                       (R2 = 0.89; n = 40)
    Sampler
    Flow Rate
    (L/Min)
    Filter Type3
                                                                   Denuded
    MOUDI
                              30
                                               Teflon (P)
                                                                    None
    HEADS
                              10
                    Teflon (N/A) GF-GFC   Carbonate
    NEW YORK SUPERSITE, NY; 06/29/01 to 08/05/01 and 07/09/02 to 08/07/02
    Urban site located at Queens College, NY, about 14 km west of Manhattan, within 2 km of freeways, and
    within 12 km of international airports. Rural site located at Whiteface mountain, 60m above sea level, in a
    clearing surrounded by deciduous and evergreen trees and no major cities within 20 km of the site.
    Sampler
    R&P-2300
    SCS
    TEOM-ACCU
    Continuous Sampler
    R&P-8400S
    PILS-IC
    AMS
    CASM
    Flow Rate
    (L/Min)
    10
    42
    16.7
    Flow Rate
    (L/Min)
    5
    5
    0.1
    5
    Filter Type3
    Nylon (N/A)
    Zefluor (N/A)
    Zefluor (N/A)
    Denuder
    Activated Carbon
    Na2C03 and Citric acid
    None
    Na2C03 and Carbon
    and a Nafion dryer
    Denuder"
    Na2C03
    None
    None
    Analysis Method'1
    S02 UV Fluorescence
    1C
    Mass Spectrometry
    S02 UV Fluorescence
                                                                       Drewnick et al. (2003. 0991 SO)'1: Hogrefe
                                                                       et al. (2004, 099003)2"
    
                                                                       Data completeness: 89-93% for R&P-8400S,
                                                                       94-98% for AMS, 81-98% for CASM, and
                                                                       65-70% for PILS-IC.
    
                                                                       The urban site data showed good
                                                                       correlations (R2 = 0.87 to 0.94) with slopes
                                                                       ranging from 0.97 to 1.01. At the rural site,
                                                                       the variability was large (R2 = 0.73 to 0.91)
                                                                       with slopes ranging from 0.76 to  1.32. S04
                                                                       from PILS-IC was overestimated by -25%
                                                                       when compared to the AMS at the rural site.
    
                                                                       Filter samples were within 5% of each other,
                                                                       except for comparison of ACCU with R&P-
                                                                       2300 at the rural site, with high correlations
                                                                       (R2 = 0.97 to 1.0). ACCU underestimated
                                                                       S042"by~15%.
    
                                                                       Continuous versus 6-h SCS filter
                                                                       comparisons showed  high R2 (0.91 to 0.95) at
                                                                       the urban site. Continuous instruments
                                                                       consistently measured lower S042~
                                                                       concentrations compared to the SCS filter
                                                                       measurements (slopes 0.68 to 0.73)
    
                                                                       On avg, 85% of the filter-based S042" was
                                                                       measured by the continuous instruments with
                                                                       consistent relationships. At the rural site,
                                                                       PILS-IC overestimated S042~ concentrations
                                                                       (slopes 1.11 to 1.15), AMS and R&P-8400S
                                                                       showed slopes of 0.71 -0.74 against SCS and
                                                                       ACCU, while it ranged from 0.53- 0.68
                                                                       against R&P-2300.
    
                                                                       Error estimates:
    
                                                                       Sampling losses: 2-3% for AMS and PILS-IC,
                                                                       5-10% for R&P-8400S and none for CASM.
    
                                                                       Continuous instruments probably
                                                                       experienced more inlet transport losses  (~
    December 2009
                                         A-39
    

    -------
                            SITE/PERIOD/SAMPLER/CONFIGURATION
                                                                             SUMMARY OF FINDINGS
                                                                                                'Ł>%) than tiller samplers due to longer inlet
                                                                                                lines.
    
                                                                                                Small (< 2%) positive artifact was found in
                                                                                                filters.
    NEWYORK SUPERSITE, NY; 10/01 to 07/05 (urban), 07/02 to 07/05 (rural)
    Urban site located at a school in South Bronx, NY in a residential area, within a few kilometers from major
    highways and a freight yard (experiencing significant truck traffic). Rural site located at Whiteface mountain,
    600m above sea level, in a clearing surrounded by deciduous and evergreen trees and no major cities within
    20 km of the site. The study by Schwab etal.89 was based at a rural site located at Pinnacle State Park
    surrounded  by golf course, picnic areas and undeveloped forest lands and no major cities within 15 km.
    Integrated Sampler
    R&P-2300
    Flow Rate
    (L/Min)
    10
    Filter Type3
    Nylon (N/A)
    Denuder"
    Na2C03
    TEOM-ACCU
                              16.7
                                              Zefluor
                                                                   None
    Continuous Sampler
    Flow Rate (L/Min)
                                                         Denuder
    Analysis Method"
    R&P-8400S
                               Activated
                               Carbon
                                                                         S02 pulsed fluorescence
    TE-5020
    
    (07/14/04to11/01/04)
                               Na2C03
    S02 pulsed fluorescence
     Rattigan et al. (2006,116897)84
    
     Data capture was above 85%. Data loss was
     primarily due to frequent flash strip failures,
     every 2 wk and without warning.
    
     Data were adjusted for span and zero drifts,
     measured conversion efficiency, flow drift,
     and blanks.
    
     Calibrations used aqueous standards of
     (NH4)2S04and oxalic acid solution in  1:4
     ratio. Lower fractions of oxalic acid showed
    - lower conversion efficiencies.
    
    - Urban South Bronx site:
    
    . R&P-8400S = 0.82 TEOM-ACCU + 1.15;
     R2 = 0.84;n = 513
    
    . R&P-8400S = 0.74 R&P-2300 + 1.14;
     R2 = 0.81; n = 322
    
     Rural Whiteface mountain:
    
     R&P-8400S = 0.75 TEOM-ACCU + 0.22;
     R2 = 0.95; n = 207
    
     R&P-8400S = 0.78 R&P-2300 + 0.17;
     R2 = 0.85; n= 198
    
     Required weekly or biweekly maintenance by
     trained personnel
    
     Schwab et al. (2006, 098786)89
    
     TE-5020 = 0.78 ACCU -0.2; R2 = 0.94
    
     Similar studies at St. Louis, MO, show slopes
     near unity. This suggests that the  instrument
     is sensitive to aerosol composition.
    
     Low maintenance and calibration
     requirements for TE-5020 compared to PILS-
     IC and R&P-8400S.
    FRESNO SUPERSITE.CA; 12/01/03 to 12/23/03
    Located 5.5 km northeast of downtown in a mixed residential-commercial neighborhood. Flow Sampler
    (L/min) Filter Typea Denuderb
                                                                      Groveretal. (2006.138080)6
    
                                                                      Dionex-IC S042"(1.03 ± 0.03) PC-BOSS S04
    Sampler
    PC-BOSS
    Flow Rate (L/Min)
    150
    Filter Type3
    Teflon (W)-
    Nylon (P)
    Denuder"
    GIF
    R&P-8400S S042" (0 95 + 0 05) Dionex-IC
    S04 + (0.3 ± 0.6); R2 = 0.68; n = 195
    
    Continuous Sampler
    R&P-8400S
    Dionex-IC
    Flow Rate (L/Min)
    5
    5
    Denuder
    Activated
    Carbon
    Parallel plate
    wet denuder
    Analysis Method"
    S02 pulsed fluorescence
    1C
    
    
    
    December 2009
                                         A-40
    

    -------
                                   SITE/PERIOD/SAMPLER/CONFIGURATION
                                                   SUMMARY OF FINDINGS
    aFilter Manufacturer in parentheses - W: Whatman, Clifton, NJ; P: Pall-Gelman, Ann Arbor, Ml; S: Schleicher & Schnell. Keene, NH; N/A: not available.
    bAI203: Aluminum oxide; 1C: Ion chromatography; GIF: Charcoal Impregnated Filter; FEP:  Fluorinated Ethylene Propylene copolymer; MgO: Magnesium oxide; Na2C03: Sodium carbonate; NaHC03: Sodium
    bicarbonate NOX: Oxides of nitrogen; S02: Sulfur dioxide; TEA: Triethanolamine; TSP: Total Suspended PM; UV: Ultraviolet; XAD-4: Hydrophobic, non-polar polyaromatic resin.
    cNa2C03 impregnated.
    d37 mm filter.
    
    
    1Chow (1995, 077012): 2Watson and Chow (2001,1571231:3 Watson et al. (1983, 045084): 4Fehsenfeld et al. (2004,1573601:5Solomon et al. (2001,1571931: BWatson et al. (2005,1571241:7Mikel (2001,
    156762): "Watson et al. (1999, 020949): 'Solomon and Sioutas (2006,156995): 10Graney et al. (2004, 053756): "Tanaka et al. (1998,157041): 12Pancras et al. (2005, 098120): "John et al. (1988, 045903):
    "Hering and Cass (1999, 0849581:15Fitz et al. (1989, 0773871:1BHering et al. (1988, 0360121: "Solomon et al. (2003,1569941:1BCabada et al. (2004,1488591: "Fine et al. (2003,1557751:2DHogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 0991601:22Watson et al. (2005,1571251:23Ho et al. (2006,1565521:24Decesari et al. (2005,1445361:25 Mayol-Bracero et al. (2002, 0450101:26Yang et al. (2003,
    156167): 27Tursic et al. (2006,157063): 2BMader et al.(2004,156724): 28Xiao and Liu (2004,  056801): 30Kiss et al. (2002,156646): 31Cornell and Jickells (1999,156367):32 Zheng et al. (2002, 026100):
    33Fraser et al. (2002,1407411: x Fraser et al. (2003, 042231135Schauer er al. (2000, 0122251:3BFine et al. (2004,1412831:37Yue et al. (2004,1571691:3BRinehart et al. (2006,1151841:39Wan and Yu (2006,
    1571041: "Poore (2000, 0128391:41Fraser et al. (2003, 0402661:42Engling et al. (2006,1564221:43Yu et al. (2005,1571671:44Tran et al. (2000, 0130251:45Yao et al. (2004,1022131:4BLi and Yu (2005,
    156692): "Henning et al. (2003,156539): 4BZhang and Anastasio (2003,157182): "Emmenegger et al. (2007,156418):50 Watson  et al, (1989,157119): 51Greaves et al. (1985,156494): 52Waterman et al.
    (2000,1571161:53Waterman et al. (2001,1571171: aFalkovich and Rudich (2001,1564271:55Chow et al. (2007,1572091:5BMiguel et al. (2004,1232601:57Crimmins and Baker (2006, 0970081:5BHo and Yu
    (2004,1565511:58Jeon et al. (2001, 0166361: BOMazzoleni et al.  (2007, 0980381: B1Poore (2002, 0514441: B2Butler et al. (2003,1563131: B3Chow et al. (2006,1466221: MRussell et al. (2004, 0824531: B5Grover
    et al. (2006,138080): BBGrover et al. (2005, 090044): B7Schwab  et al. (2006, 098449): BBHauck et al. (2004,156525): B8Jaques et al. (2004,155878): 70Rupprecht and Patashnick (2003,157207): 71Pang et al
    (2002, 0303531:72Eatough et al. (2001, 0103031:73Lee et al. (2005,128139); MLee et al. (2005,1566801:75Babich et al. (2000,1562391:7BLee et al. (2005,1559251:77Lee et al. (2005,1281391:7BAnderson
    and Ogren (1998,1562131:79Chung et al. (2001,1563571: BOKidwell and Ondov (2004,1558981: B1Lithgow et al. (2004,1266161: B2Weber et al. (2003,1571291: B3Harrison et al. (2004,1367871: "Rattigan et
    al. (2006,115897): B5Wittig et al. (2004,103413): BBVaughn et al. (2005,157089): B7Chow  et al. (2005, 099030): BBWeber et al (2001, 024640); B8Schwab et al. (2006, 098785): ™Lim et al. (2003, 037037):
    "Watson and Chow (2002, 0378731:82Venkatachari et al. (2006,1059181:83Bae et al. (2004,1562431:84Arhami et al. (2006,1562241:85Park et al. (2005,1568431:8BBae et al. (2004, 0986801:87Chow et al.
    (2006,1563501:8BArnott et al. (2005,1562271:88Bond et al. (1999,1562811:1DDVirkkula et al. (2005,1570971:1D1Petzold et al. (2002,1568631:102Park et al. (2006, 0981041:103Arnott et al. (1999, 0206501:
    "Veters et al. (2001, 016925): 105Pitchford et al. (1997,156872): 10BRees et al.  (2004, 097164): 107Watson et al. (2000, 010354): 10BLee et al. (2005,156680): 108Hering et al. (2004,155837): ™Watson et al.
    (1998,1988051: '"Chakrabarti et al. (2004,1574261:112Mathai et al. (1990,1567411: '"Kidwell and Ondov (2001.0170921: '"stanier et al. (2004, 0959551: '"Khlystovet al. (2005,1566351:11BTakahama et
    al. (2004,1570381:117Chow et al. (2005,1563481: '"Zhang et al. (2002,1571811: '"Subramanian et al. (2004, 0812031:120Chow et al. (2006,1552071: ™Birch and Cary (1996, 0260041:122Birch (1998,
    024953): 123Birch and Cary (1996, 002352): ™NIOSH (1996, 156810): 125NIOSH (1999, 156811): 12BChow et al. (1993, 077459): 127Chow et al. (2007, 156354): ™Ellis and  Novakov (1982, 156416):
    128Peterson and Richards (2002,1568611:130Schauer et al. (2003, 0370141: "iMiddlebrook et al. (2003, 0429321: "2Wenzel et al. (2003,1571391: "3Jimenez et al.  (2003,1566111: "Vhares et al. (2003,
    1568661:135Qin and Prather (2006,1568951: "BZhang et al. (2005,1571851:137Bein et al. (2005,1562651:  "BDrewnick et al. (2004,1557541: "8Drewnick et al. (2004,1557551: "°Lake et al. (2003,1566691:
    "'Lake etal. (2004, 088411)
    
    
                                                                                                                                            Source: Chow etal. (2008,156355)
    Table A-15.     Summary of PM2.6 carbon measurement comparisons.
    SITE/PERIOD/SAMPLER/CONFIGURATION
    ATLANTA SUPERSITE, GA: 08/03/99 to 09/01/99
    Four km NW of downtown, within 200 m of a bus maintenance yard and several warehouse facilities,
    representative of a mixed commercial-residential neighborhood.
    Sampler
    R&P-2000 FRM
    RAAS-400
    SASS
    MASS-450
    R&P-2300
    VAPS
    URG-PCM
    ARA-PCM
    PC-BOSS (TVA)
    PC-BOSS (BYU)
    MOUDI-100
    Continuous Sampler
    Flow Rate
    (L/Min)
    16.7
    24
    6.7
    16.7
    10
    15
    16.7
    16.7
    150
    150
    30
    Flow Rate
    (L/Min)
    Filter Type3
    Quartz (P)
    Quartz (P)
    Quartz (P)-
    Quartz (P)
    Quartz (P)
    Quartz (P)-
    Quartz (P)
    Quartz (P)
    Quartz (P)-
    Quartz (P)
    Quartz (N/A)-
    Quartz (N/A)
    Quartz (P)-
    CIF (N/A)
    Quartz (P)-CIF
    (S)
    Al Foil-Quartz
    (N/A)f
    Denuder
    Denuder1'
    None
    None
    None
    None
    None
    XAD-4
    XAD-4
    GIF
    GIF
    GIF
    None
    OC EC
    Analysis Method0
    NIOSH 5040-TOT
    NIOSH 5040-TOT
    NIOSH 5040-TOT
    NIOSH 5040-TOT
    NIOSH 5040-TOT
    NIOSH 5040-TOT
    Front: NIOSH 5040-TOT;
    Backup: custom-TOTd
    IMPROVE_TOR
    Front: IMPROVE TOR;
    Backup: TPV
    TPB
    Custom-TORtosuitAI8
    Comments
    SUMMARY OF FINDINGS
    Solomon et al. (2003, 166994) 1T
    Organic Carbon (OC);
    PM2.s OC from each sampler was compared to
    the all-sampler avg, called the relative
    reference (RR) value The samplers agreed to
    within 20 to 50% of RR. Only front filter OC is
    
    35%) than RR, while non-denuded sampler
    OC was higher (5 to 35%).
    Among non-denuded samplers, as filter face
    exception of R&P-2300.
    EC1
    PM2.5 EC from each sampler was compared to
    reference (RR) value. The samplers agreed to
    within 20 to 200% of RR.
    TOT samples showed less EC than RR by 15
    to 30%, while TOR samples showed more EC
    than RR h\/ 40 tn 00% PPRO^^ fRYl h >RR
    value by 140%. EC by TOR is -twice EC by
    TOT.
    Major difference in EC is due to the carbon
    analysis protocol and optical monitoring
    Lim etal. (2003, 037037)90
    December 2009
    A-41
    

    -------
                           SITE/PERIOD/SAMPLER/CONFIGURATION
                                                    SUMMARY OF FINDINGS
    ADI-C
                       2.7
                                   Activated Carbon
    Not
    known
    RU-OGI
                        16.1
                                   None
    700 in
    He
    R&P-5400
                        16.7
                                   None
    275 in
    air
    PSAP
                        1.26
                                   None
               Part of S04  instrument    TC concentrations measured by the RU-OGI
               w/C02 non-dispersive      and R&P-5400 correlated reasonably well
    N/A        infrared (NDIR) analyzer;   (R2 = 0.83), with a slope of 0.96. The ratio of
               data corrected for avg field  the mean RU-OGI to mean R&P-5400 TC was
               blank; OC = 2 oxidized OC  1.02.
    
                                      R&P-5400 OC was 8% lower than the RU-OGI
                                      (R2 = 0.73), while the R&P-5400 EC was 20%
                                    -higher than RU-OGI (R2 = 0.74).
    
                                      OC measured by ADI-C was lower than R&P-
                                    - 5400 and RUOGI by 15% and 22%,
                                      respectively.
    850 in 2%
    02
    TOT; Dynamic blank for
    adsorption correction
                                                          750 in air   No pyrolysis correction
            babs@
            565 nm
                                                                     10m /g factor
    AE-16
                                   None
                                                           babs@
                                                           880 nm
                       12.6 m/g factor
                                     - EC from PSAP and AE-16 correlated well
                                      (R2 = 0.97). PSAP was lower by -50%,
                                      compared with AE-16, R&P-5400 and RU-
                                      OGI.
    
                                      EC measured by AE-16 was ~12% higher
                                      than RU-OGI. Calibration factors for the light
                                      absorption instruments need to be adjusted for
                                      better correlation.
    
                                      Calibration factor might be non-linear over the
                                      range of absorbance measured.
    
                                      The mean OC from R&P-5400 and RU-OGI
                                      were within 10% of filter RR values. Mean
                                      ADI-C OC was 14% lower than filter RROC.
    
                                      EC from continuous instruments was 2-2.5
                                      times filter RR EC; continuous TC was also
                                      greater than filter RR TC by 17% (R&P-400) to
                                      27% (RU-OGI).
    December  2009
                  A-42
    

    -------
                           SITE/PERIOD/SAMPLER/CONFIGURATION
                                                                      SUMMARY OF FINDINGS
    PITTSBURGH SUPERSITE, PA; 06/01/01 to 07/31/02
    Six km east of downtown in a park on the top of a hill.
    Sampler
                        Flow
    Filter Type/Pack3
                                                            Denuder
                              Analysis Method0
                        16.7
    CMU Custom-1
                 Teflon
    Non-denuded  (P/W)-     .,.„,,
    sampte       Quartz (P)  None
                 (QBT)
                                                                           NIOSH5040-TOT
                        16.7
                                    sample
                                                                           NIOSH5040-TOT
                        16.7
    Denuded
    sample
    Denuder-
    Quartz (P)-  Activated Carbon NIOSH 5040-TOT
    CIG (S)
                        16.7
                 Teflon
    
    D^™c      Kder
    blank (DYN)   ^f(rp).
                 CIG (S)
                                                            Activated Carbon NIOSH 5040-TOT
                        16.7         Non-denuded  Teflon
                                    blank (UDB)   (P/W)-
                                                 Quartz (P)-
                                                 CIG (S)
                                                            None
                                                                           NIOSH5040-TOT
    CMU Custom-2
     Subramanian etal. (2004,081203)""
    
    . Particulate OC (POC) was estimated from
     denuded sample (Quartz OC + CIG OC) after
    - subtracting DYN POC.
    
     Denuder efficiency (1-DYN POC/UDB POC)
     was 94 ± 3%. No seasonal variability or
     deterioration in denuder performance was
    - observed.
    
     Positive artifact due to denuder breakthrough
     was 18.3 ±12.5% of the denuded sample
    . POC.
    
     Negative artifact (CIGsample-CIGDYN) was,
     on avg, 6.3 ± 6.2% of POC.
    
    " Positive artifact was 34 ± 10% from QBT, and
     was 13 ± 5% from QBQ. QBT »QBQ.
    
     QBT over-corrected the positive artifact by
     20%. OC volatilization from the front Teflon
     filter that subsequently adsorbed on the back-
    " up quartz filter, resulted in an overestimation
     of the positive artifact.
    
     Non-denuded QBQ provided a more
     representative estimate of the positive artifact
     on the non-denuded front quartz filter for 24-h
     samples. However, it was not suitable for 4- to
     6-h samples, because the filters were not in
     equilibrium with the air stream.
    
     Positive artifact dominated when  sampling
     with a non-denuded quartz filter.
    
     Comparison of 24-h avg non-denuded front
     quartz OC versus denuded POC  over the year
     showed an intercept of 0.53 ug/m3, indicative
     of a positive artifact on quartz filter samples.
    
     The artifacts were higher in summer on an
     absolute basis;  however, they showed no
     seasonal variation when expressed as a
     fraction of POC.
    ST. LOUIS SUPERSITE, IL, MO; 01/01/02 to 12/31/02
    Three km east of St. Louis, MO City center, also impacted by industrial sources, and located in a mixed
    residential light commercial neighborhood.
                                                               Bae et al. (2004,156243)93; Bae et al. (2004,
    Sampler
    University of
    Wisconsin Custom-1
    University of
    Wisconsin Custom-2
    Flow Rate
    (Lmin)
    24
    24
    Filter
    Type/Pack3
    Quartz (P)
    Denuder-Quartz
    (P)
    Denuder-Quartz
    (P)
    Teflon (N/A)-
    Denuder-Quartz
    (P)
    Denuder1'
    None
    GIF
    GIF
    GIF
    Analysis Method0
    ACE Asia TOT
    ACE Asia TOT
    ACE Asia TOT
    ACE Asia TOT
    Continuous Sampler
                                    Denuder
                                                    OC
                                                                 EC
                                                                           Comments
                                                                                               Denuder breakthrough was 0.17 ± 0.15 ug/m3,
                                                                                               and constituted less than 5% of annual avg
                                                                                               OC concentration.
    
                                                                                               Non-denuded OC = (1.06 ± 0.02) x denuded
                                                                                               OC +(0.34 ±0.10)
    
                                                                                               Equivalence of OC intercept and denuder
                                                                                               breakthrough implies that the low-level artifact
                                                                                               is caused by denuder breakthrough.
    
                                                                                               Non-denuded EC = (1.04 ± 0.03)  x denuded
                                                                                               EC + (0.07 ± 0.03), indicating negligible EC
                                                                                               artifact.
    
                                                                                               Results suggested  higher summertime OC
                                                                                               artifact, on an absolute basis.
    December 2009
                                   A-43
    

    -------
                           SITE/PERIOD/SAMPLER/CONFIGURATION
                                        SUMMARY OF FINDINGS
    Sunset OCEC
                                   GIF
                                                   340,
                                                   500,615,
                                                   870°C in
                                                   100% He
    550, 625,
    700, 775,
    850, 900
    °C in 2%
    02, 98%
    He
    ACE Asia TOT; CH4   Comparison of continuous Sunset TC and OC
    FID detector         with 24-h filter samples showed good
                       correlations (R2) of 0.89 and 0.90,
                       respectively.
    
                       Continuous Sunset TC
                       in ug/m3 = (0.97 ± 0.02) x filter TC +
                       (0.83 ± 0.11), indicating comparability with the
                       filter measurements.
    
                       Continuous Sunset OC = (0.93 ± 0.02) x filter
                       OC +(0.94 ±0.09)
    
                       Positive intercept was interpreted to be a
                       blank correction for the continuous
                       measurements.
    
                       EC comparison was poor with large scatter in
                       data (R2 = 0.60), probably due to low EC
                       concentrations (avg = 0.70 ug/m3), close to
                       the detection limit (0.5 ug/m3).
    FRESNO SUPERSITE, CA and other CRPAQS sites; 12/02/99 to 02/03/01, 12/1/03 to 11/30/04
    Fresno Supersite was located 5.5 km northeast of downtown in a mixed residential-commercial
    neighborhood.
    Sampler
    DRI-SFS
    RAAS-400
    RAAS-400
    RAAS-100 FRM
    Continuous Sampler
    R&P-5400
    Sunset OCEC
    MAAP
    AE-16
    AE-21
    AE-31
    DRI-PA
    Sampler
    Flow Rate
    (Lmin)
    113
    24
    24
    16.7
    Flow Rate
    (L/Min)
    16.7
    8.5
    16.7
    6.8
    6.8
    6.8
    3
    Flow Rate
    (Lmin)
    Filter
    Type/Pack3
    Quartz (P)
    Teflon (P)-
    Quartz (P)
    (QBT)
    (P) (QBT)
    Quartz (P)-
    Quartz (P)
    (QBQ)
    Quartz (P)-
    Quartz (P)
    (QBQ)
    Quartz (P)
    Denuder
    None
    CIG
    None
    None
    None
    None
    None
    Filter
    Type/Pack3
    Denuder1'
    None
    None
    None
    XAD-4/CIF
    None
    OC EC
    275°Cinair ?f°°C in
    air
    650, 750,
    850,
    940°C in
    2%02in
    He
    babs@
    670 nm
    babs@
    880 nm
    icn cnn
    650, 850°C babs @
    in He 370, 880
    nm
    babs@
    370, 470,
    520, 590,
    660, 880
    and 950
    nm
    babs@
    1047 nm
    Denuder11
    Analysis Method0
    IMPROVE_TOR
    IMPROVE_TOR
    IMPROVE_TOR
    IMPROVE_TOR
    IMPROVE_TOR
    Comments
    No pyrolysis
    correction
    Transmittance
    Transmittance
    6.5 m2/g factor
    Transmittance
    14625/Am2/g factor,
    where A is in nm
    Absorption, 5 m2/g
    factor
    Analysis Method0
    Watson and Chow (2002, 037873)91; Chow
    et al. (2005, 166348)"7; Chow et al. (2006,
    155207)120; Watson et al. (2005, 157124)6;
    Non-denuded RAAS-400 and RAAS-100 FRM
    400 and RAAS-100 FRM samplers showed
    comparability for front filter TC, OC and EC
    measurements.
    Positive OC artifact was 1 .62 ± 0.58 ug/m3
    (~24% of non-denuded front quartz OC) from
    QBT, and 1 .12 ± 0.91 ug/m3 (-17% of non-
    denuded front quartz OC) from QBQ. QBT
    »QBQ
    positive OC artifact of 34% (of the non-
    denuded front quartz OC) from QBT and
    17.5% (of the non-denuded front quartz OC)
    from QBQ.
    Positive artifact was higher during summer
    than winter.
    Negative artifact was, on avg,
    0.61 ± 0.58 ug/m3 (-10% of POC) at Fresno.
    Over all the CRPAQS sites, it ranged from
    2.3% in winter to 11 % in summer, with an avg
    of 4.9%.
    Positive artifact is estimated to be 0.5 ug/m3.
    No difference in denuded quartz backup OC
    denude rs.
    against filter samples showed poor correlation
    (R2<0.55).
    TC from R&P-5400 was 40-60% higher than
    filter TC by TOR. None of the R&P-5400
    versus TOR filter comparisons were
    comparable or predictable, due to several
    frequent instrument malfunctions during the
    experiment and the small data set (-35 data
    points).
    IMPROVE_TOR EC was consistently 20-25%
    higher than aethalometer BC.
    IMPROVE TOR EC was comparable to
    MAAP BC.
    Comparison of light absorption (babs) from
    DRI-PA (1047 nm), MAAP (670 nm), and AE
    December 2009
      A-44
    

    -------
                        SITE/PERIOD/SAMPLER/CONFIGURATION                           SUMMARY OF FINDINGS
    PC-BOSS
    Continuous Sampler
    R&P-5400
    150
    Flow Rate
    (L/Min)
    16.7
    Quartz (P)-CIG
    (S)t
    Denuder
    None
    GIF
    OC
    375°C in air
    
    EC
    750°C in
    air
    TPV
    Comments
    No pyrolysis
    (880 nm) analyzers witn tne tiller
    IMPROVE_TOR EC, gave a oabs of 2.3, 5.5
    and 10 m /g, differing from the default
    conversion factors of 5, 6.5, and 16.6 mz/g
    used for each instrument at the specified
    wavelength
    Grover et al. (2006, 138080)65
                                                                                   R&P-5400 TC = (0.50 ± 0.01) Sunset TC +
                                                                                   (3.6±1.5);R2=0.73;n = 480
                                               „,_„,-„„     650750                  Sunset TC = [0.63 ±0.05) PC-BOSS TC +
                                               250,500,    o?nipi"'  NIOSH 5040 TOT   (4 1+3 2V R2= 086'n = 29
    Sunset OCEC         8.0         CIG          650,850°C   °5°Ł'"           ~      l*-!--^,*  u.oo.n
                                               in He       PRO/ HP  NDIR c°2 detector  R&R-5400 TC = (0.41 ± 0.02) PC-BOSS TC H
                                                          98/oHe                  (6.7±1.6);R2=0.91;n = 29
    December 2009                                         A-45
    

    -------
    SITE/PERIOD/SAMPLER/CONFIGURATION
    BALTIMORE SUPERSITE, MD; 02/1 5/2002 to 11/30/2002
    East of downtown in an urban residential area. Within 91 m of bus maintenance facility.
    Sampler
    SASS
    Continuous Sampler
    Sunset OCEC
    Flow Rate
    (L/Min)
    6.7
    Flow Rate
    (L/Min)
    8
    Filter
    Type/Pack3
    Quartz (P)-
    Quartz (P)
    Denuded
    Carbon
    Denuded
    None
    OC
    600°C,
    then
    870°C in
    He
    
    
    EC
    870°C in
    2% 02 in He
    Analysis Method0
    STN_TOT
    Comments
    TOT; CH4 FID
    detector; Denuder
    breakthrough ~
    0.5-1 ug C/m3; Used
    0.5 to correct OC
    concentrations
    RUBIDOUX, CA; 07/13/03 to 07/26/03
    Rubidoux is located in the eastern section of the South Coast Air Basin (SoCAB) in the northwest corner of
    Riverside County, 78 km downwind of the central Los Angeles metropolitan area and in the middle of the
    remaining agricultural production area in SoCAB.
    Sampler
    PC-BOSS
    Continuous Sampler
    Sunset OCEC
    Sunset OCEC
    Flow Rate
    (L/Min)
    150
    Flow Rate
    (L/Min)
    8
    8
    Filter
    Type/Pack3
    Quartz (P)-CIG
    (S)
    Denuded
    GIF
    GIF
    Denuded
    GIF
    OC
    N/A
    N/A
    
    
    EC
    N/A
    Not meas-
    ured
    Analysis Method0
    TPB (CIG heated to
    450 °C in N2)
    Comments
    TOT; NDIR detector;
    NIOSH 5040
    protocol
    TOT; has blank
    quartz filter before
    entering analyzer.
    Used as "blank"
    stream for
    quantifying OC
    artifacts;3-step
    analysis only in He.
    NEW YORK SUPERSITE, NY; 01/12/04 to 02/05/04
    Urban site located at Queens College, NY, about 14 km west of Manhattan, within 2 km of freeways, and
    within 12 km of international airports.
    Integrated Sampler
    R&P-2300
    
    Continuous Sampler
    R&P-5400
    Sunset OCEC
    AE-20
    AMS
    Flow Rate
    (L/Min)
    10
    
    Flow Rate
    (L/Min)
    16.7
    N/A
    N/A
    N/A
    Filter
    Type/Pack3
    Quartz
    
    Denuded
    None
    GIF
    None
    None
    Denuded
    None
    
    OC
    340 °C in
    air
    600, 870
    °C in He
    
    N/A
    
    
    
    EC
    750 °C in
    air
    870 °C at
    10%02in
    He
    babs@370,
    880 nm
    N/A
    Analysis Method0
    STN_TOT
    
    Comments
    No pyrolysis
    correction
    Transmittance
    Transmittance,
    14625 A m2/g factor,
    where A is in nm
    ~ 1 urn cut-point
    SUMMARY OF FINDINGS
    Parketal. (2005, 156843)95
    Data capture 93.8%
    Compared to SASS, Sunset underestimated
    OC and EC by 22% and -11 .5%, respectively.
    Higher OC in SASS was attributed to the
    absence of a denuder (i.e., positive artifact by
    gaseous adsorption) and to temperature
    - differences between the STN_TOT and
    Sunset TOT carbon analysis temperature
    protocols.
    EC discrepancy was probably related to the
    differences in temperature protocol.
    Grover et al. (2005, 090044)66
    Sunset OCEC TC = (0.90 ± 0.06) PC-BOSS +
    (2.0±2.1);R2=0.93;n = 21
    Sunset TC was adjusted for carbon artifacts
    measured by second (blank) instrument.
    Venkatachari et al. (2006, 106918)92
    Regression of OC from Sunset OCEC against
    - PM2s mass concentration yielded an intercept
    of 1 .14 ug/m3, which was used as a measure
    of the positive artifact on the Sunset data. The
    - Sunset OC data was corrected for this artifact.
    - AE-20 BC concentrations were -86% of
    Sunset EC and R&P2300 filter EC
    - concentrations.
    AE-20 versus R&P-5400 showed high scatter.
    Sunset Optical EC = 0.58 ± 0.05 Sunset
    Thermal EC; R2 = 0.86; n = 506
    Sunset Optical EC = 0.62 ± 0.05 AE-20 BC;
    - R2 = 0.96; n = 539
    R&P-5400 TC tracked filter TC closely, but
    differed widely for OC and EC.
    Sunset OC = (0.75 ± 0.76) R&P-2300 OC +
    (0.08 ± 0.36); R2 = 0.67; n = 16
    Sunset OC = (0.98 + 0.11) R&P-5400 OC -
    (0.47±0.17);R2 = 0.44;n = 327
    December 2009
    A-46
    

    -------
                                  SITE/PERIOD/SAMPLER/CONFIGURATION
                                                  SUMMARY OF FINDINGS
                                                                                                                           R&P-5400 OC =  (0.60 ± 0.47) R&P-2300 OC
                                                                                                                           + (0.58 ± 0.82); R2= 0.58; n = 17
                                                                                                                           Organic  matter measurements byAMS
                                                                                                                           showed  reasonable correlation (R2 = 0.76)
                                                                                                                           with filter (R&P-2300) OC, while  being poorly
                                                                                                                           correlated with continuous OC by Sunset
                                                                                                                           (R2 = 0.32)  and R&P-5400 (R2 =  0.36)
                                                                                                                           Sunset EC  = (1.21 ± 0.44) R&P-2300 EC -
                                                                                                                           (0.03 ± 0.13); R2  = 0.94; n = 16
                                                                                                                           Sunset EC  = (1.35 ± 0.12) R&P-5400 EC +
                                                                                                                           (0.06 ±0.04);R2  = 0.61; n = 327
                                                                                                                           R&P-5400 EC =  (0.49 ± 0.46) R&P-2300 EC +
                                                                                                                           (0.09 ± 0.26); R2  = 0.77; n = 15
                                                                                                                           Sunset TC = (0.86 ± 0.39) R&P-2300 TC -
                                                                                                                           (0.06 ± 0.69); R2  = 0.77; n = 16
                                                                                                                           Sunset TC = (1.31 ±0.10) R&P-5400TC-
                                                                                                                           (1.15 ± 0.15); R2  = 0.59; n = 327
                                                                                                                           R&P-5400 TC = (0.77 ± 0.58) R&P-2300 TC +
                                                                                                                           (0.35±1.37);R2  = 0.83;n = 16
    aFilter Manufacturer in parentheses - W: Whatman, Clifton, NJ; P: Pall-Gelman, Ann Arbor, Ml; S: Schleicher & Schnell. Keene, NH; N/A: not available. QBT: quartz backup filter behind Teflon front filter. QBQ:
    quartz backup filter behind Quartz front filter.
    bAI203: Aluminum oxide; 1C: Ion chromatography; GIF: Charcoal Impregnated Filter; CIG: Charcoal Impregnated Glass-Fiber Filter; FEP: Fluorinated Ethylene Propylene copolymer; MgO: Magnesium oxide;
    Na2C03: Sodium carbonate; NaHC03: Sodium bicarbonate NOX: Oxides of nitrogen; S02: Sulfur dioxide; TEA: Triethanolamine; TSP: Total Suspended PM; UV: Ultraviolet; XAD-4: (hydrophobic, non-polar
    polyaromatic resin.
    CNIOSH 5040_TOT: National Institute of Occupational Safety and Health Method 5040 Thermal Optical Transmittance Protocol. "1122'123' ™' "5 OC: 250, 500, 650, 850 °C for OC1, OC2, OC3, and OC4
    fractions, respectively, for 60, 60, 60, 90 sec respectively, in 100% He atmosphere. EC: 650, 750, 850, 940 °C for EC1, EC2, ECS, and  EC4 fractions, respectively, 30, 30, 30, >120 sec respectively, in 98% He
    and 2% 02 atmosphere. OPT: Pyrolysis correction by transmittance. IMPROVE_TOR:  Interagency Monitoring of Protected Visual Environments Thermal Optical Reflectance Protocol 12B OC fractions: 120,
    250, 450, 550 °C for OC1, OC2, OC3, and OC4 fractions,  respectively, until a well defined peak has evolved at each step, with a time limit of min 80 sec and max  of 580 sec, in 100% He atmosphere. EC
    fractions: 550, 700, 800 °C for EC1, EC2, and ECS fractions, respectively, until a well defined peak has evolved  at each step, with a time limit of min 80 sec and max of 580 sec, in 2% 02 and 98% He
    atmosphere. OPR: Pyrolysis correction for pyrolyzed organic carbon (OP) by reflectance. OC = OC1+OC2+OC3+OC4+OP EC = EC1+EC2+EC3-OPTC = OC+EC. IMPROVE_ATOR:  127 Note that as of
    May, 2007, the U.S. EPA is switching samples from the Speciation Trends Network thermal optical transmittance protocol to the IMPROVE_A protocol. OC: 140, 280, 480, 580 °C for OC1, OC2, OC3, and
    OC4, fractions, respectively, until a well defined peak has evolved at each step, with a time limit of 80 sec and max of 580 sec, in 100% He atmosphere EC: 580, 740, 840 °C for EC1, EC2, and ECS fractions,
    respectively, until a well defined peak has evolved at each step, with a time limit of min 80 sec and max of 580 sec, in 2% 02and 98% He atmosphere. OPR: Pyrolysis correction for pyrolyzed organic carbon
    (OP) by reflectance. OPT: Pyrolysis correction by transmittance. TPV: Temperature Programmed Volatilization "' B112B For CIF Filters: Heated from 50 °C to 300 °C at a ramp rate of 10 °C/min in N2. For
    Quartz filters: Heated from 50 °C to 800 °C at a ramp rate of 28 °C/min in 70% N2 and 30% 02; EC estimated from  high temperature peak (>450 °C) on thermogram obtained from quartz-fiber filter analysis;
    No pyrolysis correction. STN_TOT: Speciation Trends Network Thermal Optical Transmittance Protocol.129 OC: 310, 480, 615, 920 °C for 60, 60, 60, 90 sec respectively, in 100% He atmosphere. EC: 600,
    675, 750, 825, 920 °C for 45, 45, 45, 45,120 sec respectively,  in 98% He and 2% 02 atmosphere. ACE Asia TOT: Aerosol Characterization Experiments in Asia Thermal Optical Transmittance Protocol. 130
    OC: 340, 500, 615, 870 °C for 60, 60, 60, 90 sec  respectively, in 100% He atmosphere. EC: 550, 625, 700, 775, 850, 900 °C for45, 45,  45, 45, 45,120 sec respectively, in 98% He, 2% 02. Pyrolysis correction
    by transmittance.
    dCustom TOT: XAD-4 impregnated quartz, analyzed in He-only atmosphere with a maximum temperature 176 °C; EC is not measured.
    eCustom TOR to suit Al substrate; details not reported.
    '37 mm filter
    
    
    'Chow (1995, 0770121:2Watson and Chow (2001,1571231:3 Watson et al. (1983, 0450841:4Fehsenfeld et al. (2004,1573601:5Solomon et al. (2001,1571931: BWatson et al. (2005,1571241:7Mikel (2001,
    1567621: BWatson et al. (1999, 0209491:8Solomon and Sioutas (2006,1569951:1DGraney et al. (2004, 0537561: "Tanaka et al. (1998,1570411:12Pancras et al. (2005, 0981201: "John et al. (1988, 0459031:
    "Hering and Cass (1999, 084958): 15Fitz et al. (1989, 077387): 1BHering et al. (1988, 036012): "Solomon et al.  (2003,156994): 1BCabada et al. (2004,148859): "Fine et al. (2003,155775): 20Hogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 0991601:22Watson et  al. (2005,1571251:23Ho et al. (2006,1565521:24Decesari et al. (2005,1445361:25 Mayol-Bracero et al. (2002, 0450101:2BYang et al. (2003,
    1561671:27Tursic et al. (2006,1570631:2BMader et al.(2004,1567241:28Xiao and Liu (2004, 0568011:30Kiss et al. (2002,1566461:31Cornell and Jickells (1999,1563671:32 Zheng et al. (2002, 0261001:
    33Fraser et al. (2002,140741): x  Fraser et al. (2003, 042231) 35Schauer er al. (2000, 012225): 3BFine et al. (2004,141283): 37Yue et al. (2004,157169): 3BRinehart et al. (2006,115184): 38Wan and Yu (2006,
    1571041:40Poore (2000, 0128391:41Fraser et al. (2003, 0402661:42Engling et al. (2006,1564221:43Yu et al. (2005,1571671:44Tran et al. (2000, 0130251:45Yao et al. (2004,1022131:4BLi and Yu (2005,
    1566921: "Henning et al. (2003,1565391:4BZhang and Anastasio (2003,1571821:48Emmenegger et al. (2007,1564181:50 Watson et al, (1989,1571191:51Greaves et al. (1985,1564941:52Waterman et al.
    (2000,157116): 53Waterman et al. (2001,157117): aFalkovich  and Rudich (2001,156427): 55Chow et al. (2007,157209): 5BMiguel et al. (2004,123260): 57Crimmins and Baker (2006, 097008): 5BHo and Yu
    (2004,1565511:58Jeon et al. (2001, 0166361: BDMazzoleni et al. (2007, 0980381: B1Poore (2002, 0514441:B2Butler et al. (2003,1563131: B3Chow et al. (2006,1466221: "Russell et al. (2004, 0824531: B5Grover
    et al. (2006,1380801: BBGrover et al. (2005, 0900441: B7Schwab et al. (2006, 0984491:  BBHauck et al. (2004,1565251: B8Jaques et al. (2004,1558781:7DRupprecht and Patashnick (2003,1572071:71Pang et al
    (2002, 030353): 72Eatough et al. (2001, 010303):  73Lee et  al. (2005,128139); MLee et  al. (2005,156680): 75Babich et al. (2000,156239): 7BLee et al. (2005,155925): 77Lee et al. (2005,128139): 7BAnderson
    and Ogren (1998,1562131:78Chung et al. (2001,1563571: BOKidwell and Ondov (2004,1558981: B1Lithgow et al. (2004,1266161: B2Weber et al. (2003,1571291: B3Harrison et al. (2004,1367871: MRattigan et
    al. (2006,1158971: B5Wittig et al. (2004,1034131:  BBVaughn et al. (2005,1570891: B7Chow et al. (2005, 0990301: BBWeber et al (2001,  0246401; B8Schwab et al. (2006, 0987851:8DLim et al. (2003, 0370371:
    81Watson and Chow (2002, 037873): 82Venkatachari et al.  (2006,105918): 83Bae et al. (2004,156243): 84Arhami et al. (2006,156224): 85Park et al. (2005,156843): ™Bae et al. (2004, 098680): 87Chow et al.
    (2006,1563501:8BArnott et al. (2005,1562271: "Bond et al. (1999,1562811: "°Virkkula et al. (2005,1570971:101Petzold et al. (2002,1568631: "2Park et al. (2006, 0981041:103Arnott et al. (1999, 0206501:
    "Veters et al. (2001, 0169251:105Pitchford et al.  (1997,1568721: "BRees et al. (2004, 0971641:107Watson et al. (2000, 0103541: "BLee et al. (2005,1566801: "8Hering et al. (2004,1558371: ™Watson et al.
    (1998,198805): 111Chakrabarti et al. (2004,157426): 112Mathai et al. (1990,156741): '"Kidwell and Ondov (2001,017092): '"Stanier et al. (2004, 095955): '"Khlystovet al. (2005,156635): '"Takahama et
    al. (2004,1570381:117Chow et al. (2005,1563481:11BZhang et al. (2002,1571811: '"Subramanian et al. (2004, 0812031:120Chow et  al. (2006,1552071: "1 Birch and Cary (1996, 0260041:122Birch (1998,
    0249531: 123Birch and Cary (1996, 0023521: ™NIOSH (1996, 1568101:125NIOSH (1999, 1568111:12BChow et al. (1993, 0774591: 127Chow et al. (2007, 1563541: 12BEllis and Novakov (1982, 1564161:
    128Peterson and Richards (2002,156861): 130Schauer et al. (2003, 037014): "iMiddlebrook et al. (2003, 042932): "2Wenzel et al. (2003,157139): "3Jimenez et al. (2003,156611): "Vhares et al. (2003,
    1568661:135Qin  and Prather (2006,1568951: "BZhang et al. (2005,1571851:137Bein et al. (2005,1562651:  "BDrewnick et al. (2004,1557541: "8Drewnick et al. (2004,1557551: MOLake et al. (2003,1566691:
    "'Lake etal. (2004, 088411)
    
    
                                                                                                                                            Source: Chow etal. (2008,1563551
    December 2009
    A-47
    

    -------
    Table A-16.    Summary of particle mass spectrometer measurement comparisons.
    
    
    ATLANTA SUPERSITE, GA: 08/03/99 to 09/01/99
    Four km NW of downtown, within 200 m of a bus maintenance yard and several warehouse facilities, representative of a mixed commercial-residential neighborhood.
    Spectrometer
    
    PALMS
    
    
    
    ATOFMS
    
    
    
    
    
    RSMS-II
    
    
    
    
    
    
    AMS
    
    
    
    Inlet Characteristics (Flow Rate
    [L/Min]; Size Inlet; Dryer
    Aerodynamic Diameter, (jrn;
    Particle Sizing Method)
    N/A
    PM2.5 cyclone
    Nafion (17 days) / None (4 days)
    0.35-2.5
    Light scattering
    1
    None
    None
    0.2-2.5
    Aerosol TOP
    
    N/A
    Nonp
    INUI 1C
    Nafion
    0.015-1.3
    Aerodynamic focusing; Need to
    pre-select sizes to be analyzed
    
    
    
    
    N/A
    PM2.5 cyclone
    None
    0.05-2.5
    Aerosol TOP
    
    
    
    Volatilization/
    lonization Hit Rates
    Method"
    LDI,
    ArF193nm 14 to 100%,
    a „ overall 87%
    2x10 to 5x10
    W/cm2
    
    LDI,Nd:YAG266 25.30o/0
    nm laser occasionally
    ~1x108W/cm2 as low as 5%
    
    
    
    LDI, Arf laser, 193
    nm
    8 8 N/A
    1x108to2x108
    W/cm2
    
    
    
    
    
    
    T~550°C/ El N/A
    
    
    
    Mass Spectrometer
    
    Single TOP reflectron;
    Ion polarity needs to
    be pre-selected
    
    
    Dual TOP reflectron;
    Detects both positive
    and negative ions
    
    
    
    
    Single linear TOP; Ion
    polarity needs to be
    pre-selected
    
    
    
    
    
    Quadrupole;
    Mass weighted size
    distributions on pre-
    selected positive ions
    onlv
    
    
    
    Particle Analysis/
    Classification
    
    Peak ID/regression
    tree analysis
    
    
    
    Aerosol TOP
    
    
    
    
    
    Peak ID/artificial
    neural network
    
    
    
    
    
    
    ID using standard
    El ionization
    databases
    
    
    
    Other
    
    Pure sulfuric
    acid (H2S04),
    (NH4)2S04,
    and water
    (H20)
    have relatively
    high ionization
    thresholds (i.e.
    difficult to
    ionize).
    Fraction of
    molecules
    ionized in the
    particles is on
    the order of
    10"5to10"6.
    
    Does not
    detect/ analyze
    highly
    refractory
    materials such
    as metals, sea
    salt, soot etc.
    Fraction of
    molecules
    ionized in the
    particles is on
    the order of
    10'6to10'7
    Middlebrook et al. (2003, 042932)131; Wenzel et al. (2003,157139)132; Jimenez et al. (2003,1666111133
    
    Particle sizing is approximate in PALMS, while ATOFMS, RSMS-II and AMS provide relatively accurate particle sizing.
    
    Particle transmission in AMS is ~100% (i.e., it uses all particles in the sampled air) between 60 and 600 nm, while that for PALMS, ATOFMS and RSMS-II
    range from 10-6 for submicron particles to 2% for supermicron (>0.8 urn) particles.
    
    AMS has fewer matrix effects (due to separate volatilization and ionization steps) compared to single-step LDI instruments.
    
    While four major particle classifications (organic/S042~, sodium/potassium sulfate, soot/hydrocarbon and mineral) were observed by all three laser
    instruments, they differed in the classification frequencies. Differences in frequencies that are detected and grouped are related to the differences in the
    laser ionization conditions (e.g., wavelength), particle transmission,  sizing method and the way the spectra were classified.
    
    Shorter ionization wavelengths are able to produce ions more easily than longer ones.
    
    Low hit rates in ATOFMS corresponded to periods of high S042~ concentrations. Low hit rates in PALMS were related to a variety of factors including high
    Sp42~ concentrations, differing laser fluence and  laser position relative to particle beam. Use of a dryer in PALMS enhanced ionization of particles that were
    difficult to ionize at high ambient RH.
    
    The RSMS-II and ATOFMS were less sensitive to S042~ and hence  may have fewer organic/S042~ particles (i.e., underestimate S042~, pure sulfuric acid
    etc.).
    
    The PALMS, ATOFMS and RSMS (laser based instruments) are qualitative, while the AMS can be quantitative. The relative ratio of ion intensities from the
    laser instruments, however, may be indicative of  relative concentrations, thus giving semi-quantitative information.
    
    Comparison of the ratio of N03 to  S04 peaks with the results from the  semi continuous instruments showed better correlation with the AMS (R2 = 0.93) than
    PALMS (R2 = 0.65 for non-dry particles to 0.70 for dry particles). While reasonable correlations between the  PALMS and the composite semi-continuous
    data indicate the possibility for calibration of laser-based data  for certain ions, the calibration factors may vary depending on the particle  matrix, water
    content and laser ionization parameters, and averaging the spectra  according to these factors may minimize these effects.
    
    Comparison of AMS S04with PILS S04 showed good correlation (R2= 0.79), and the data uniformly scattered around a 1:1 line. N03 comparison was poor
    (R2 = 0.49) because of the low signal to noise ratio at low concentrations
    
    The continuum between particle classifications indicates that the particles were not adequately represented by non-overlapping classifications.
    December 2009
    A-48
    

    -------
    ATLANTA SUPERSITE, GA: 08/03/99 to 09/01/99
    Four km NW of downtown, within 200 m of a bus maintenance yard and several warehouse facilities, representative of a mixed commercial-residential neighborhood.
    
    HOUSTON SUPERSITE, TX; 08/23/00 to 09/18/00
    Houston Regional Monitoring Site was located < 1.0 km north of the Houston ship channel, where chemical and other industries are present. The site was
    located between a railway to the south and a chemical plant to the north. Major freeways were located just to the north and east of the sampling site.
    Inlet Characteristics (Flow Rate
    c»./.tr~~.t.r [L/Min]; Size Inlet; Dryer
    Spectrometer Aerodynamic Diameter, Vm;
    Particle Sizing Method)
    
    
    
    N/A
    IN/r\
    None
    PCMC M Nafion
    Kbivib-ii 0.035-1.14
    Aerodynamic focusing; Need to
    pre-select sizes to be analyzed
    
    
    
    Volatilization/ pa,+i,.i»
    lonization HitRatesb Mass Spectrometer0 n™,
    MothrwH' UaSSI
    ivicuiuQ
    
    
    
    
    
    LDI ArF laser Single linear TOF; lon Peak ID/a
    193nm ' N/A pre-selecteddS '° ^ neural net
    
    
    
    flcation'5' Other
    
    At each size
    point, aerosol
    was sampled
    in each cycle
    for either 10
    riif. . i min or until
    ™^' mass spectra
    worK for 30 particles
    per major
    class were
    collected,
    whichever
    came first.
    Phares et al. (2003,166866V34
    
    27,000 spectra were classified using a neural network into 15 particle types
    
    Fifteen particle type mass spectra were presented along with their size distribution, avg time of day occurrence, and wind direction dependence
    
    Major classes were a K+ dominant, Si/Silicon Oxide, Carbon, Sea Salt, Fe, Zn, Amines, Lime, Vanadium, Organic Mineral, Pb and K, Al, and a Pb salt
    particle type.
    
    FRESNO SUPERSITE, CA: 11/30/00 to 2/4/01
    Urban location in a residential neighborhood.
    Spectrometer
    
    
    
    ATOFMS
    
    
    
    Inlet Characteristics (Flow Rate
    [L/Min]; Size Inlet; Dryer
    Aerodynamic Diameter, urn;
    Particle Sizing Method)
    
    
    1
    None
    None
    0.3-2.5
    Aerodynamic
    
    
    Volatilization/ D rt-
    lonization HitRatesb Mass Spectrometer0 nfll,*^*™
    Method3 Classification
    
    
    
    miNn-YAfi Peak ID/artificial
    ORR nm N/A Dual reflectron TOF
    266 nm neural network
    
    
    
    Other
    ATOFMS
    unsealed
    detected
    particles
    tracked p
    attenuation
    monitor PM2.s
    mass
    concentration
    Qin and Prather (2008,166986V35
    
    Biomass burning particles reached a maximum at night and a minimum during the day. These particles were less than 1 urn in diameter and accounted for
    more than 60% of the particles detected at night.
    
    Another particle class characterized by high mass carbon fragments had a similar diurnal pattern. These particles were larger than 1  urn and were
    interpreted as biomass particles that have undergone gas to particle conversion of semi-volatile species followed by dissolution in a water droplet.
    
    PITTSBURGH SUPERSITE, PA; 09/07/02 TO 09/22/02 FORAMS; 09/20/01 to 09/26/02 for RSMS-III
    6 km east of downtown in a park on the top of a hill
    Spectrometer
    AMS
    Inlet Characteristics (Flow Rate [L/Min];
    Size Inlet; Dryer Aerodynamic
    Diameter, urn; Particle Sizing Method)
    1 .4 cc/s
    PM2.s cyclone
    None
    0.05-1.0
    Aerosol TOF
    Volatilization/
    lonization
    Method"
    T-600°C/EI
    Hit Rates
    Quadrupole;
    Mass weighted size distributions on
    pre-selected positive ions only.
    Mass Spectrometer0
    Particle size-cut of ~1 urn
    RSMS-II
    N/A
    None
    Nafion
    0.03-1.1
    Aerodynamic focusing; Need to pre-
    select sizes to be analyzed.
    LDI.ArF laser, 193
    nm
    Dual TOF feflectron; Detects both
    positive and negative ions
    At each size point, aerosol
    was sampled in each cycle for
    either 10 min or until mass
    spectra for 30 particles per
    major class were collected,
    whichever came first
    December  2009
                                                    A-49
    

    -------
    ATLANTA SUPERSITE, GA: 08/03/99 to 09/01/99
    Four km NW of downtown, within 200 m of a bus maintenance yard and several warehouse facilities, representative of a mixed commercial-residential neighborhood.
    
    Zhang et al. (2005,1671861136: Bein et al. (2005,1662661137
    
    The AMS observed 75% of the S042" measured by R&P-8400S (R2 = 0.69).
    
    Collection efficiency (CE) of 0.5 used for S042~, N03and NH4+and 0.7 for organics to correct mass concentrations for incomplete detection. Use of a
    constant CE irrespective of size and shape may overestimate accumulation mode (mostly, oxygenated) organics (true CE ~ 0.5) and underestimate smaller
    mode (primary) organics (true CE ~ 1.0).
    
    Comparison of AMS organics (organic  matter, OM) with OC measured by a continuous Sunset OCEC instrument showed good correlation (R2 = 0.88) with
    aslope of 1.69.A24-h avg comparison, showed a slope of 1.45. These values are in the typical range of 1.2 to 2.0 for OM/OC ratios.
    
    AMS could be used along with the SMPS to estimate particle density. The AMS did not always agree with SMPS, probably due to non-spherical particles
    (irregular) such as soot from fresh traffic emissions, whose mass may be overestimated by the SMPS.
    
    Comparison of AMS mass with the MOUDI, showed  differences for aerodynamic diameters >600 nm, probably due to the AMS transmission being less than
    unity for particles larger than 600 nm.
    
    For RSMS-III, 54% of the detected particles were assigned to one  class  (carbonaceous ammonium nitrate). This class was preferentially detected during
    the colder months and was detected from many different wind directions.
    
    The next largest RSMS-III class was EC/OC/K class at 11%, and is believed to be from biomass burning.
    
    An unidentified organic carbon RSMS-III class (3.3% of all detected particles) was seen to be highly dependent on wind direction dependence and was
    primarily detected during August and September of 2002. These particles likely originated from a landfill.
    
    NEW YORK SUPERSITE; 06/30/01  to 08/05/01 (urban); 07/09/02 to 08/07/02: (rural)
    Urban Site: Queens College,  Queens,  New York, located at the edge of a parking lot and within 1 km from expressways and highways in New York City
    Metropolitan area.
    
    Rural Site: Whiteface Mountain, New York, located in a cleared area surrounded by  mix of deciduous and evergreen trees, ~2 km away from the closest
    highway with no major cities within 20 km.
    Inlet Characteristics (Flow
    .„.„„._ Rate [L/Minl; Size Inlet; Dryer
    Spectrometer Aerodynamic Diameter, um;
    Particle Sizing Method)
    0.1
    PM2.5 cyclone
    AMS None
    0.02-2.5
    Aerosol TOF
    Volatilization/
    lonization
    Method9
    T-700°C/EI
    Hit Rates
    Quadrupole;
    Mass weighted size
    distributions on pre-
    selected positive ions
    only.
    Mass Spectrometer0
    Data are 10-min
    averages
    Drewnick et al. (2004,1667641138: Drewnick et al. (2004,155755)139; Hogrefe et al. (2004,099003)20
    
    Transport losses were 1.3% on avg.
    
    Inlet losses (at the in let of AMS) were 1.9%, on avg, ranging from 11% for a 20 nm particle to 9% for a 2.5 um particle, with a minimum of 0.7% for a 350 nm
    particle
    
    Overall measurement uncertainty of particle diameter was ~11%.
    
    The AMS was reliable with  proper calibration, care, and maintenance. Valid 10 min averages were obtained for all components more than 93% of the time.
    
    The mass to  charge ratios (m/z) of fragments from different components may overlap (e.g., NH+, a fragment of NH4+ and CH3+, a fragment of organic
    species, have m/z = 15) resulting in an interference (called as isobaric interference) Interfering signals were not used to calculate concentrations. This loss
    in concentration was adjusted by applying a correction factor determined from laboratory studies.
    
    Typical interferences were from fragments of organic species, water and oxygen.
    
    With adjustments, the S042~, N03~ and ammonium concentrations measured by the AMS were consistently lower than that measured by other co-located
    instruments,  probably due to incomplete focusing of the (NH4)2S04and NH4N03 particles by the aerodynamic lens.
    
    At the urban  site, AMS N03 was within 10% of the filter N03 concentration. At the rural site, it had a slope of 0.51 and R2 of 0.46.
    
    AMS S04 showed good agreement with R&P-8400S at both the rural and urban  locations (R2 = 0.89 to 0.92, slope = 0.99, n = 407 to 695) and was within
    70 to 85% of filter S042" concentration.
    
    Comparison of the total non-refractory mass measured by the AMS with the PM2.s TEOM mass (operated at 50°C or with dryer) at the urban location,
    showed good correlation (R2 = 0.91) with near zero intercept (0.22 ug/m3). On avg, the AMS observed 64% of the mass measured by the TEOM.
    
    The unexplained mass (36%) was attributed to transport losses, transmission  and optical losses, and refractory components in the aerosol sample (e.g.,
    metals, EC). The mass closure was within the estimated uncertainty of the AMS  mass measurements (5-10%).
    December 2009
    A-50
    

    -------
    ATLANTA SUPERSITE, GA: 08/03/99 to 09/01/99
    Four km NW of downtown, within 200 m of a bus maintenance yard and several warehouse facilities, representative of a mixed commercial-residential neighborhood.
    BALTIMORE SUPERSITE, MD; 04/01/02 to 11/30/02
    East of downtown in an urban residential area. Within 91 mofa bus maintenance facility.
    Inlet Characteristics (Flow W«I,*;M,,««»/
    ^rtromPtPr Rate [L/Min]; Size Inlet Dryer Vua±±n/
    Spectrometer Aerodynamic Diameter, |im Sin"
    Particle Sizing Method) Metnoa
    0.2-18, based on particle size
    chosen
    None
    RSMS-III 0 MW 3 LDI, ArF laser, 193 nm
    Aerodynamic focusing; Need
    topre-selectsizestobe
    analyzed
    Hit Rates Mass Spectrometer
    At each size set point,
    aerosol was sampled
    in each cycle for either
    TOP with dual ion polarity m,ln *ir un LJT1355
    spectra trom ju
    particles were
    collected, whichever
    came first.
    Lake et al. (2003,166669)140, Lake et al. (2004,088411)141
    
    Utilizing both positive and negative ion detection enables detection of more species. However, detection efficiencies of negative ions decreased for smaller
    particles.
    
    S04+ concentration (number or mass) was not accurately quantified.
    
    RSMS-III was most efficient in 0.050 to 0.77 um range.
    
    Particle compositions could be related to specific source categaories.
    
    aEI: Electon  Impact; LDI: Laser Desorption / lonization
    bHitrate refers to the number of particles with a mass spectrum as a fraction of the number of particles detected. It does not apply to RSMS and AMS because there is no separate detection
    cTOF: Time fo Flight
    
    1Chow (1995, 0770121:2Watson and Chow (2001,1571231:3 Watson et al. (1983, 0450841:4Fehsenfeld et al. (2004,1573601:5Solomon et al. (2001,1571931: BWatson et al. (2005,1571241:7Mikel (2001,
    1567621: "Watson et al. (1999, 0209491: 'Solomon and Sioutas (2006,1569951:10Graney et al. (2004, 0537561: "lanaka et al. (1998,1570411:12Pancras et al. (2005, 0981201: "John et al. (1988, 0459031:
    "Hering  and Cass (1999, 084958): 15Fitz et al. (1989, 077387): 1BHering et al. (1988, 036012): "Solomon et al. (2003,156994): 1BCabada et al. (2004,148859): "Fine et al. (2003,155775): 20Hogrefe et al.
    (2004, 0990031:21Drewnick et al. (2003, 0991601:22Watson et al. (2005,1571251:23Ho et al. (2006,1565521:24Decesari et al. (2005,1445361:25 Mayol-Bracero et al. (2002, 0450101:2BYang et al. (2003,
    1561671:27Tursic et al. (2006,1570631:2BMader et al.(2004,1567241:23Xiao and Liu (2004, 0568011:30Kiss et al. (2002,1566461:31Cornell and Jickells (1999,1563671:32 Zheng et al. (2002, 0261001:
    33Fraser  et al. (2002,140741): x  Fraser et al. (2003, 042231) 35Schauer er al. (2000, 012225): 3BFine et al. (2004,141283): 37Yue et al. (2004,157169): 3BRinehart et al. (2006,115184): 38Wan and Yu (2006,
    1571041: "Poore (2000, 0128391:41Fraser et al. (2003, 0402661:42Engling et al. (2006,1564221: J3Yu et al. (2005,1571671:44Tran et al. (2000, 0130251:45Yao et al. (2004,1022131:4BLi and Yu (2005,
    1566921: "Henning et al. (2003,1565391:4BZhang and Anastasio (2003,1571821: "Emmenegger et al. (2007,1564181:50 Watson  et al, (1989,1571191:51Greaves et al. (1985,1564941:52Waterman et al.
    (2000,157116): 53Waterman et al. (2001,157117): 54Falkovich and Rudich (2001,156427): 55Chow et al. (2007,157209): 5BMiguel et al. (2004,123260): 57Crimmins and Baker (2006, 097008): 5BHo and Yu
    (2004,1565511:58Jeon et al. (2001, 0166361: BOMazzoleni et al. (2007, 0980381: B1Poore (2002, 0514441:B2Butler et al. (2003,1563131:  B3Chow et al. (2006,1466221: MRussell et al. (2004, 0824531: B5Grover
    et al. (2006,1380801: BBGrover et al. (2005, 0900441: B7Schwab et al. (2006, 0984491: BBHauck et al. (2004,1565251: B8Jaques et al. (2004,1558781:70Rupprecht and Patashnick (2003,1572071:71Pang et al
    (2002, 030353): 72Eatough et al. (2001, 010303): 73Lee et al. (2005,128139); 7\ee et al. (2005,156680): 75Babich et al. (2000,156239): 7BLee et al. (2005,155925): 77Lee et al. (2005,128139): 7BAnderson
    and Ogren (1998,1562131:79Chung et al. (2001,1563571: BOKidwell and Ondov (2004,1558981: B1Lithgow et al. (2004,1266161: B2Weber et al. (2003,1571291: B3Harrison et al. (2004,1367871: "Rattigan et
    al. (2006,1158971: B5Wttig et al. (2004,1034131: BBVaughn et al. (2005,1570891: B7Chow et al. (2005, 0990301: BBWeber et al (2001, 0246401; B8Schwab et al. (2006, 0987851: ™Lim  et al. (2003, 0370371:
    "Watson and Chow (2002, 037873): 82Venkatachari et al. (2006,105918): 33Bae et al. (2004,156243): MArhami et al. (2006,156224): 85Park et al. (2005,156843): %Bae et al. (2004, 098680): 37Chow et al.
    (2006,1563501:8BArnott et al. (2005,1562271: "Bond et al. (1999,1562811: "°Virkkula et al. (2005,1570971:101Petzold et al. (2002,1568631:102Park et al. (2006, 0981041:103Arnott et al. (1999, 0206501:
    ""Peters et al. (2001, 0169251:105Pitchford et al. (1997,1568721:10BRees et al. (2004, 0971641:107Watson et al. (2000, 0103541: ™Lee et al. (2005,1566801: ™Hering et al. (2004,1558371: ™Watson et al.
    (1998,198805): 111Chakrabarti et al. (2004,157426): 112Mathai et al. (1990,156741): '"Kidwell and Ondov (2001,017092): ™Stanier et al. (2004, 095955): '"Khlystovet al. (2005,156635): '"Takahama et
    al. (2004,1570381:117Chow et al. (2005,1563481:11BZhang et al. (2002,1571811: ™Subramanian et al. (2004, 0812031: "°Chow et al. (2006,1552071:  "'Birch and Cary (1996, 0260041:122Birch (1998,
    0249531: 123Birch and Cary (1996, 0023521: ™NIOSH (1996, 1568101: "5NIOSH (1999, 1568111:12BChow et al. (1993, 0774591: 127Chow et al. (2007, 1563541: ™Ellis and Novakov (1982, 1564161:
    "'Peterson and Richards (2002,156861): 130Schauer et al. (2003,  037014): "iMiddlebrook et al. (2003, 042932): "2Wenzel et al. (2003,157139): "3Jimenez et al. (2003,156611): "Vhares et al. (2003,
    1568661:135Qin  and Prather (2006,1568951:  "BZhang et al. (2005,1571851:137Bein et al. (2005,1562651:  "BDrewnick et al. (2004,1557541: "3Drewnick et al. (2004,1557551: "°Lake et al. (2003,1566691:
    "'Lake etal. (2004, 088411)
    
    
                                                                                                                                             Source: Chow etal. (2008,1563551
    December  2009
    A-51
    

    -------
    Table A-17.    Summary of key parameters for TD-GC/MS and pyrolysis-GC/MS.
    Reference
    Sample Type
    TD-GC/MS WITH RESISTIVELY HEATED EXTERNAL
    Greaves etal. (1985, 156494;
    1987, 156495) ;Veltkampet
    al. (1996,081594)
    Waterman et al. (2000,
    157116)
    Waterman et al. (2001 ,
    157117)
    Sidhu etal. (2001, 155202)
    Aerosol sample and NISTSRM
    1649
    NISTSRM 1640a
    NISTSRM 1649a
    TDUnit
    OVEN
    A cylindrical aluminum block
    containing a heating cartridge
    connected to a thermocouple
    External oven mounted on the top
    of the GC/MS system
    Same as above
    Aerosol collected on glass fiber A stainless steel tube (0.635 cm
    filters from combustion of alternative °-D-) laced m a GC oven
    dieselfuel.
    Analytical Instrument
    
    HP5892AGC/MSinEI
    mode
    HP5890GC/Fisons
    MD 800 MS, scan
    range: 40-520 amu
    HP5890GC/Fisons
    MD 800 MS, scan
    range: m/z 40 to 520
    Two GCs and one MS. The
    firstGCis used as the TE
    unit. The second GC
    separates the desorbent.
    Total Analysis
    Time
    
    ambient sample:
    55.5 min NIST
    standard: 45.5
    min
    90 min
    90 mins
    Ua
    Hays et al. (2003,156529:    Aerosol collected from residential
    2004.156530): Dong et al.    wood combustion, residential oil
    (2004,156409)              furnace and fireplace appliance
                                   A glass tube placed in an external
                                   oven (TDS2 Gerstel Inc.)
                                                                  Agilent 6890 GC/5793 MSD,
                                                                  scan range: 50 to 500 amu   99 mjn
    CURIE POINT TD-GC/MS
    Jeon etal. (2001, 016636)
    Neusussetal. (2000,
    156804)
    High-volume PM10 ambient samples
    collected along the U.SVMexico Curie point pyrolyzer HP 5890 GC/5792 MSD Ua
    border
    Ambient aerosol collected during the
    2nd Aerosol Characterization Curie point pyrolyzer Fisons Trio 1 000 35 min
    Experiment
    IN-INJECTION PORT TED-GC/MS
    u i  •   t i
    neimigeiai.
    Aerosol samples collected on glass-  GC injector port, with modified
    fiber filters at a forest site           septum cap
                                                                  Carlo ErbaMega5160
                                                                  GC/VG 250/70 SE MS, scan  47 min
                                                                  range: 45-400 amu
    Hall etal. (1999.156512)
                              NISTSRM 1649
                                   Micro-scale sealed vessel placed
                                   inside the injector port
                                                                  HP5890GC/FisonsMD800
                                                                  MS, scan range: 40-500      82.5 min
                                                                  amu
    ai.
    Aerosol samples collected on
    quartz-and-glass filters in Ontario
                                   AGC injection port was added with
                                   three minor components, including
                                   a small T-connector, 3-way valve,
                                   and needle valve
                                                                                            HP 5892A GC/5972A MS in
                                                                                            El mode
                                                                                                                    71 min
    Falkovich and Rudich (2001,
    156427); Falkovich et al.
    (2004,156428); Graham et
    al. (2004,156490)
    NISTSRM 1649a; urban aerosols    Direct Sample Introduction (DSI)
    collected with an 8-stage impactor in device (ChromatoProbe, Varian
    Tel-Aviv, Israel                   Co.)
                                                                  Varian Saturn 3400 GC/MS   64.2 min
    Ho and Yu (2004.156551):
    Yang et al. (2005,102388)
    Ambient aerosol samples collected
    on Teflon-impregnated glass-fiber
    filters in Hong Kong and on quartz
    filters at Nanjing, China
                                   Conventional GC injection port. No
                                   modification of GC injector and liner
    HP5890GC/5791 MSD,
    scan range: 50-650 amu
    TD-GCXGC-MS
    Welthagen et al. (2003,
    104056) ; Schnelle-Kreis etal.
    (2005, 112944)
    Hamilton et al. (2004,
    156516)
    Hamilton et al. (2005,
    088173)
    Ambient samples in Augsburg,
    Germany
    PM2.s aerosol collected in London
    Secondary organic aerosol formed
    during the photo-oxidation of
    toluene with OH radicals
    Injection port Optic III with
    autoloader (ATAS-GL, Veldhoven,
    NL)
    Conventional GC injection port
    The same as above
    Agilent 6890 GC/LECO
    Pegasus III TOF/MS with a
    LECO Pegasus 4D GCxGC
    modulator
    The same as above, scan
    range: 20-350 amu
    The same above
    175 min
    93.7 min
    102.5 min
    December 2009
                                        A-52
    

    -------
            Reference                 Sample Type                      TD Unit              Analytical Instrument   Total Analysis
    IN SITU SEMI-CONTINUOUS AND CONTINUOUS TD SYSTEMS
    IAI-II-      »  i ™inc -icc-ic7\  In situ aerosol samples collected in   Collection-TE cell with conventional  Agilent 6890 GC/5793 MSD,  cn   •
    Williams etal. (2006,156151)  Berkley, CA       	GC injection port	scan range: 29-550 amu     59 mln
    
    
    PYROLYSIS TD-GC/MS
    
    
    Voorhees etal. (1991,         PM0 6 and PM>0.45 collected on       A tube furnace directly interfaced to  Extrel Simulscan GC/MS,    ,, ,  .
    1571011                    quartz fiber m pristine regions of     anQC/MS                       scan range: 35-450 amu     317mln
    
    
    Subbalakshmi et al. (2000,     Ambient aerosol collected on glass-  „    . .  ,                      Agilent 6890 GC/5973 MS,   R,,-  .
    157023)                    fiber filters in Jakarta, Indonesia     M pyromjecior                     scan range: 50-550 amu     DJ'° mln
    
                               DM    I,  (  .     i   ,.  f.,(     A pyrolyzer directly connected to the  Varian 3400 GC/Saturn II ion
    Fabbri etal. (2002,156426)    jnantSrialareaof Itahf         GC injector port through an         trap MS, scan range: 45-400  57 min
                                                    '         interface heated at 250° C          amu
    
                               PM2.6 collected on quartz-fiber filters
    
    Blazso etal. (2003,156278)    sSmpledlS^n ATfoill in     A pyrolyzer                       Agilent 6890 GC/5973 MS    30.3 min
    
                               Brazil
    
    
    Labbanetal. (2006,156665)   ™q0Uafrtz3-torPfiltedrsd S°''C°"ected   Curie point pyrolyzer               HP5890 GC/5972 MS       25.5. min
    
    
    3Total analysis time could not be determined because of insufficient experimental details
    
    
                                                                                                            Source: Chow etal. (2007,157209)
    December 2009                                               A-53
    

    -------
    A.1.2.  Networks
    Table A-18.     Relevant Spatial Scales for PMio, PM2.6, and  PMi0.2.6 Measurement
       Spatial
       Scales
    PMio
    PMZ5
    PMlO-2.5
    Microscale     This scale would typify areas such as
                   downtown street canyons, traffic corridors, and
    (-6-100 m)     fence |jne stationary source monitoring
                   locations where the general public could be
                   exposed to maximum PMio concentrations.
                   Microscale PM sites should be located near
                   inhabited buildings or locations where the
                   general public can be expected to be exposed
                   to the concentration measured. Emissions from
                   stationary sources such as primary and
                   secondary smelters, power plants, and other
                   large industrial processes may, under certain
                   plume conditions, likewise result in high ground
                   level concentrations at the microscale. In the
                   latter case, the microscale would represent an
                   area impacted by the plume with dimensions
                   extending up to approximately 100 m. Data
                   collected at microscale sites provide
                   information for evaluating and developing hot
                   spot control measures.
                             This scale would typify areas such as downtown
                             street canyons and traffic corridors where the
                             general public would be exposed to maximum
                             concentrations from mobile sources. In some
                             circumstances, the microscale is appropriate for
                             particulate sites; community-oriented SLAMS sites
                             measured at the microscale level should,
                             however, be limited to urban sites that are
                             representative of long-term human exposure and
                             of many such microenvironments in the area. In
                             general, microscale PM sites should be located
                             near inhabited buildings or locations where the
                             general public can be expected to be exposed to
                             the concentration measured. Emissions from
                             stationary sources such as primary and secondary
                             smelters, power plants, and other large industrial
                             processes may, under certain plume conditions,
                             likewise result in high ground level concentrations
                             at the microscale. In the latter case, the
                             microscale would represent an area impacted  by
                             the plume with dimensions extending up to
                             approximately 100 m. Data collected at
                             microscale sites provide information for evaluating
                             and developing hot spot control measures. Unless
                             these sites are indicative of population-oriented
                             monitoring, they may be more appropriately
                             classified as SPM.
                              This scale would typify relatively small areas
                              immediately adjacent to: industrial sources;
                              locations experiencing ongoing construction,
                              redevelopment, and soil disturbance; and
                              heavily traveled roadways. Data collected at
                              microscale stations would characterize
                              exposure over areas of limited spatial extent
                              and population exposure, and may provide
                              information useful for evaluating and
                              developing source-oriented control measures.
    Middle Scale   Much of the short-term public exposure to
                   coarse fraction particles (PM10) is on this scale
    (-100-600 m)   anc| on the neighborhood scale. People moving
                   through downtown areas or living near major
                   roadways or stationary sources, may
                   encounter particulate pollution that would be
                   adequately characterized by measurements of
                   this spatial scale. Middle scale PM10
                   measurements can be appropriate for the
                   evaluation of possible short-term exposure
                   public health effects. In many situations,
                   monitoring sites that are representative of
                   micro-scale or middle-scale impacts are not
                   unique and are representative of many similar
                   situations. This can occur along traffic corridors
                   or other locations in a residential district.  In this
                   case, one location is representative of a
                   neighborhood of small scale sites and is
                   appropriate for evaluation of long-term or
                   chronic effects. This scale also includes the
                   characteristic concentrations for other areas
                   with dimensions of a few hundred meters such
                   as the parking lot and feeder streets
                   associated with shopping centers, stadia, and
                   office buildings. In the case of PM10, unpaved
                   or seldomly swept parking lots associated with
                   these sources could be an important source in
                   addition to the vehicular emissions themselves.
                             People moving through downtown areas, or living
                             near major roadways, encounter particle
                             concentrations that would be adequately
                             characterized by this spatial scale. Thus,
                             measurements of this type would be appropriate
                             for the evaluation of possible short-term exposure
                             public health effects of PM pollution. In many
                             situations, monitoring sites that are  representative
                             of microscale or middle-scale impacts are not
                             unique and are representative of many similar
                             situations. This can occur along traffic corridors or
                             other locations in a residential district. In this case,
                             one location is representative of a number of
                             small scale sites and is appropriate  for evaluation
                             of long-term or chronic effects. This  scale also
                             includes the characteristic concentrations for other
                             areas with dimensions of a few hundred meters
                             such as the parking lot and feeder streets
                             associated with shopping centers, stadia, and
                             office buildings.
                              People living or working near major roadways
                              or industrial districts encounter particle
                              concentrations that would be adequately
                              characterized by this spatial scale. Thus,
                              measurements of this type would be
                              appropriate for the evaluation of public health
                              effects of PM10.25 exposure. Monitors located in
                              populated areas that are nearly adjacent to
                              large industrial point sources of PMio-2 5
                              provide suitable locations for assessing
                              maximum population exposure levels and
                              identifying areas of potentially poor air quality.
                              Similarly, monitors located in populated areas
                              that border dense networks of heavily-traveled
                              traffic are appropriate for assessing the
                              impacts of resuspended road dust. This scale
                              also includes the characteristic concentrations
                              for other areas with dimensions of a few
                              hundred meters such  as school grounds and
                              parks that are nearly adjacent to major
                              roadways and industrial point sources,
                              locations exhibiting mixed residential and
                              commercial development, and downtown areas
                              featuring office buildings, shopping centers,
                              and stadiums.
    December 2009
                                         A-54
    

    -------
       Spatial
       Scales
    PMio
    PMzs
    PMlO-2.5
    Neighborhood  Measurements in this category represent
    Scale          conditions throughout some reasonably
                   homogeneous urban sub-region with
    (-600 m-4 km)  dimensions of a few kilometers and of
                   generally more regular shape than the middle
                   scale. Homogeneity refers to the PM
                   concentrations, as well as the land use and
                   land surface characteristics. In some cases, a
                   location carefully chosen to provide
                   neighborhood scale data would represent not
                   only the immediate neighborhood but also
                   neighborhoods of the same type in other parts
                   of the city. Neighborhood scale PMio sites
                   provide information about trends and
                   compliance with standards because they often
                   represent conditions in areas where people
                   commonly live and work for extended periods.
                   Neighborhood scale data could provide
                   valuable information for developing, testing,
                   and revising models that describe the larger-
                   scale concentration patterns, especially those
                   models relying on spatially smoothed emission
                   fields for inputs. The neighborhood scale
                   measurements could also be used for
                   neighborhood comparisons within or between
                   cities.
                             Measurements in this category would represent
                             conditions throughout some reasonably
                             homogeneous urban sub- region with dimensions
                             of a few kilometers and of generally more regular
                             shape than the middle scale. Homogeneity refers
                             to the PM concentrations, as well as the land use
                             and land surface characteristics. Much of the
                             PM25 exposures are expected to be associated
                             with this scale of measurement. In some cases, a
                             location carefully chosen to provide  neighborhood
                             scale data would represent the immediate
                             neighborhood as well as neighborhoods of the
                             same type in other parts of the city. PM25 sites of
                             this kind provide good information about trends
                             and compliance with standards because they
                             often represent conditions  in areas where people
                             commonly live and work for periods  comparable to
                             those specified in the NAAQS. In general, most
                             PM25 monitoring in urban areas should have this
                             scale.
                              Measurements in this category would
                              represent conditions throughout some
                              reasonably homogeneous urban sub-region
                              with dimensions of a few kilometers and of
                              generally more regular shape than the middle
                              scale. Homogeneity refers to the PM
                              concentrations, as well as the land  use and
                              land surface characteristics. This category
                              includes suburban neighborhoods dominated
                              by residences that are somewhat distant from
                              major roadways and industrial districts but still
                              impacted by urban sources, and areas of
                              diverse land use where residences are
                              interspersed with commercial and industrial
                              neighborhoods.  In some cases, a location
                              carefully chosen to provide neighborhood scale
                              data would represent the immediate
                              neighborhood as well as neighborhoods of the
                              same type in other parts of the city.  The
                              comparison of data from middle scale and
                              neighborhood scale sites would provide
                              valuable information for determining the
                              variation of PM10-2.5 levels across urban areas
                              and assessing the spatial extent of elevated
                              concentrations caused by major industrial point
                              sources and heavily traveled roadways.
                              Neighborhood scale sites would provide
                              concentration data that are relevant to
                              informing a large segment of the population of
                              their exposure levels on a given day.
    Urban Scale
                                                              This class of measurement would be used to
                                                              characterize the PM concentration over an entire
                                                              metropolitan or rural area ranging in size from 4 to
                                                              50 kilometers.  Such measurements would be
                                                              useful for assessing trends in area-wide air
                                                              quality, and hence, the effectiveness of large scale
                                                              air pollution control strategies. Community-
                                                              oriented PM25  sites may have this scale.
    Regional
    Scale
    
    (-60-1 OOs km)
                             These measurements would characterize
                             conditions over areas with dimensions of as much
                             as hundreds of kilometers. As noted earlier, using
                             representative conditions for an area implies
                             some degree of homogeneity in that area. For this
                             reason, regional scale measurements would be
                             most applicable to sparsely populated areas.  Data
                             characteristics of this scale would provide
                             information about larger scale processes of PM
                             emissions,  losses and transport. PM25 transport
                             contributes to elevated  particulate concentrations
                             and may affect multiple urban and State entities
                             with large populations such as in the eastern
                             United States. Development of effective pollution
                             control strategies  requires an understanding at
                             regional geographical scales of the emission
                             sources and atmospheric processes that are
                             responsible for elevated PM25 levels and may also
                             be associated with elevated 03 and regional haze.
    December 2009
                                         A-55
    

    -------
    Table A-19.   Major routine operating air monitoring networks9
        Network      Lead   Number  Initiated   Measurement
                    Agency  of Sites            Parameters
                   Location of Information and/or Data
    STATE /LOCAL I FEDERAL NETWORKS
    NCoreb - National Core EPA 75 2008
    Monitoring Network
    SLAMS1 State and EPA ~3000 1978
    Local Ambient
    Monitoring Stations
    STN-PM15 Speciation EPA 300 1999
    Trends Network
    PAMS— Photochemical EPA 75 1994
    Assessment
    Monitoring Network
    IMPROVE NPS 110 plus 1988
    Interagency Monitoring 67 protocol
    of Protected Visual sites
    Environments
    CASTNet- Clean Air EPA 80+ 1987
    Status and Trends
    Network
    GPMN-Gaseous NPS 33 1987
    Pollutant Monitoring
    Network
    POMS-Portable NPS 14 2002
    Ozone Monitoring
    Stations
    Passive Ozone NPS 43 1995
    Sampler Monitoring
    Program
    NADP/NTN— National USGS 200+ 1978
    Atmospheric
    Deposition Program /
    National Trends
    Network
    NADP/MDN— National None 90+ 1996
    Atmospheric
    Deposition Program /
    Mercury Deposition
    Network
    03, NO/N02/NOV, S02,
    CO, PM2.5/PM10-2.5,
    PM25speciation, NH3,
    HN03, surface
    meteorology0
    03, NOX/N02, S02,
    PM2.5/PM10, CO, Pb
    PM2.5, PM2.5
    speciation, major
    Ions, metals
    03, NOx/NOy, CO,
    speciated VOCs,
    carbonyls, surface
    meteorology SUpper
    Air
    PM2.5/PM10, major
    ions, metals, light
    extinction, scattering
    coefficient
    03, S02, major ions,
    calculated dry
    deposition, wet
    deposition, total
    deposition for
    sulfur/nitrogen,
    surface meteorology
    03, N0x/N0/N02,
    S02, CO, surface
    meteorology, (plus
    enhanced monitoring
    of CO, NO, NOX,
    NOY, and S02 plus
    canister samples for
    VOC at 3 sites)
    03, surface
    meteorology, with
    CASTNet-protocol
    filter pack (optional)
    sulfate, nitrate,
    ammonium, nitric
    acid, sulfur dioxide
    03 dose (weekly)
    Major Ions from
    precipitation
    chemistry
    Mercury from
    precipitation
    chemistry
    http ://www.epa .gov/ttN/Amtic/monstratdoc .html
    http://www.epa.gov/air/oaqps/qa/monproa.html
    http://www.epa.gov/ttnamti1/specqen.html
    http://www.epa.gov/air/oaqps/pams/
    http://vista.cira.colostate.edu/IMPROVE/
    http ://www.epa .gov/castnet/
    http://www2.nature.nps.gov/air/Monitoring/network.cfmtfdata
    
    http://www2.nature.nps.gov/air/studies/port03.cfm
    http://www2.nature.nps.gov/air/Studies/Passives.cfm
    
    http://nadp.sws.uiuc.edu/
    http://nadp.sws.uiuc.edu/mdn/
    December 2009
    A-56
    

    -------
    Network Lead Number Initiated
    Agency of Sites
    AIRMoN— National NOAA 8 1992
    Atmospheric
    Deposition Program /
    Atmospheric Integrated
    Research Monitoring
    Network
    lADN-lntegrated EPA 20 1990
    Atmospheric
    Deposition Network
    NAPS— National Air Canada 152+ 1969
    Pollution Surveillance
    Network
    CAPMoN— Canadian Canada 29 2002
    Air and Precipitation
    Monitoring Network
    Mexican Air Quality Mexico 52-62 Late
    Network 1960s
    Mexican City Ambient Mexico 49 Late
    Air Quality Monitoring 1 960s
    Network
    Measurement
    Parameters
    Major Ions from
    precipitation
    chemistry
    Note: some sites
    began in 1976 as part
    oftheDOEMAPSS
    program; early data
    are archived on
    NADPandARL
    servers.
    PAHs, PCBs, and
    organochlorine
    compounds are
    measured in air and
    precipitation samples
    S02, CO, 03, NO,
    N02, NOX, VOCs,
    SVOCs,PM10, PM25,
    TSP, metals
    03, NO, N02, NOY,
    PAN,NH3,PM2.5,
    PMio and coarse
    fraction mass, PM2.5
    speciation, major ions
    for particles and trace
    gases, precipitation
    chemistry for major
    ions
    03, NOX, CO, S02,
    PM10,TSP,VOC
    03, NOx, CO, S02,
    PM10,TSP,VOC
    Location of Information and/or Data
    http://nadp.sws.uiuc.edu/AIRMoN/
    http://www.epa.aov/alnpo/monitoring/air/
    http://www.etc-cte.ec.gc.ca/NAPS/index e.html
    http://www.msc.ec.gc.ca/capmon/index e.cfm
    http://www.ine.aob.mx/daicur/calaire/indicadores.html
    
    http://www.ine.aob.mx/daicur/calaire/indicadores.html
    
    AIR TOXICS MONITORING NETWORKS
    NATTS— National Air EPA 23 2005
    Toxics Trends Stations
    State/Local Air Toxics EPA 250+ 1987
    Monitoring
    NDAMN-National EPA 34 1998-2005
    Dioxin Air Monitoring
    Network
    VOCs, Carbonyls,
    PM,o metalsd, Hg
    VOCs, Carbonyls,
    PM,o metalsd, Hg
    CDDs, CDFs, dioxin-
    like PCBs
    http://www.epa.aov/ttN/Amtic/airtoxpg.html
    http://www.epa.gov/ttN/Amtic/airtoxpg.html
    http://cfpub.epa.gov/ncea/CFM/recordisplav.cfm?deid=54811
    
    TRIBAL MONITORING NETWORKS
    Tribal Monitoring' EPA 120+ 1995
    03, NOX/N02, S02,
    PM2.5/PM10, CO, Pb
    http://www.epa.gov/air/tribal/airprogs.htmltfambmon
    INDUSTRY/ RESEARCH NETWORKS
    New Source Permit None variable variable
    Monitoring
    HRM Network None 9 1980
    Houston Regional
    Monitoring Network
    ARIES /SEARCH— None 8 1992
    Aerosol Research
    Inhalation
    Epidemiology Study /
    Southeastern Aerosol
    Research and
    Characterization Study
    experiment
    03, NOX/N02, S02,
    PM2.5/PM10, CO, Pb
    03, NOx, PM25/PM10,
    CO,S02, Pb.VOCs,
    surface meteorology
    03, NO/N02/NOY,
    S02, CO, PM2.5/PM10,
    PM2.5 speciation,
    major Ions, NH3,
    HN03, scattering
    coefficient, surface
    meteorology
    Contact specific industrial facilities
    http://hrm.radian.com/houston/how/index.htm
    http://www.atmospheric-research.com/studies/SEARCH/index.html
    
    December 2009
    A-57
    

    -------
    Network Lead Number Initiated Measurement
    Agency of Sites Parameters
    SOS-SERON- EPA -40
    Southern Oxidant
    Study - Southeastern
    Regional Oxidant
    Networks
    1990 03, NO, NOY, VOCs,
    CO, surface
    meteorology
    Location of Information and/or Data
    http://www.ncsu.edu/sos/pubs/sos3/State of SOS
    
    3.pdf
    
    NATIONAL/GLOBAL RADIATION NETWORKS
    RadNet formerly EPA 200+
    Environmental
    Radiation Ambient
    Monitoring System
    (ERAMS)
    SASP Surface Air DHS 41
    Sampling Program
    NEWNET DOE 26
    Neighborhood
    Environmental Watch
    Network
    1973 Radionuclides and
    radiation
    1963 89Sr, 90Sr, naturally
    occurring
    radionuclides, 7Be,
    210Pb
    1993 Ionizing gamma
    radiation, surface
    meteorology
    http://www.epa.aov/enviro/html/erams/
    http://www.eml.st.dhs.gov/databases/sasp/
    http://newnet.lanl.gov/
    SOLAR RADIATION NETWORKS
    UV Index EPASunrise EPA
    Program9
    UV Net Ultraviolet EPA
    Monitoring Program
    NEUBrew (NOAA-EPA NOAA
    Brewer
    Spectrophotometer UV
    and Ozone Network
    UV-B Monitoring and USDA
    Research Program
    SURFRAD- Surface NOAA
    Radiation Budget
    Network
    AERONET Aerosol NASA
    RObotic NETwork co-
    located
    networks
    MPLNET Micro-pulse
    Lidar Network
    PRIMENet-Park NPS
    Research
    & Intensive Monitoring of
    Ecosystems NETworl?
    -50 U.S. 2002 Calculated UV
    cities radiation index
    21 1995/2004 Ultraviolet solar
    radiation (UV-B and
    UV-A bands),
    irradiance, ozone,
    N02
    6 2005 Ultraviolet solar
    radiation (UV-B and
    UV-A bands),
    irradiance, ozone,
    S02
    35 1992 Ultraviolet-B radiation
    7 1993 Solar and infrared
    radiation, direct and
    diffuse solar
    radiation,
    photosynthetically
    active radiation, UVB,
    spectral solar, and
    meteorological
    parameters
    22 + other 1998 Aerosol spectral
    participants optical depths,
    aerosol size
    distributions, and
    precipitable water
    8 2000 Aerosols and cloud
    layer heights
    14 1997 ozone, wet and dry
    deposition, visibility,
    surface meteorology,
    and ultraviolet
    radiation
    http://www.epa.gov/sunwise/uvindex.html
    http://www.epa.gov/uvnet/access.html
    http://www.esrl.noaa.gov/gmd/grad/neubrew/
    http://uvb.nrel.colostate.edu/UVB/index.isf
    http://www.srrb.noaa.gov/surfrad/index.html
    http://aeronet.gsfc.nasa.gov/index.html
    http://mplnet.gsfc.nasa.gov/
    http://www.cfc.umt.edu/primenet/Assets/Announcements/99PReport.pdf
    
    3Some networks listed separately may also serve as subcomponents of other larger listed networks; as a result, some double counting of the number of individual monitors is likely.
    bNCore is a network proposed to replace NAMS, as a component of SLAMS; NAMS are currently designated as national trends sites.
    Surface meteorology includes wind direction and speed, temperature, precipitation, relative humidity, solar radiation (PAMS only).
    dPM10 metals may include arsenic, beryllium, cadmium, chromium, lead, manganese, nickel, and others.
    eThe number of sites indicated for tribal monitoring is actually the number of monitors, rather than sites. The number of sites with multiple monitors is probably <80.
    f Sunrise program estimates UV exposure levels through modeling - does not include measurements.
    9NEUBREW is a subset Original UV brewer network (UV Net); PRIMENET participated in UV Net program.
    December 2009
    A-58
    

    -------
    A.1.3. Monitor Distribution with Respect to Population Density
                        Atlanta Combined Statistical Area
                                : Kilometers
              0  5 10   20   30  40  50
              01
            2005 Population Density
            |    Atlanta PMzs Monitors (15 km buffer)
            Population per Sq Km
            j^B °-89
            j^l 90-177
                178-886
                887-1772
              | 1773-4431
            ^H 4432-17722
              0  15 30   60   90   120  150
                                   : Kilometers
    Figure A-1.    PM2.s monitor distribution in comparison with population density, Atlanta, GA.
    December 2009
    A-59
    

    -------
                      Atlanta Combined Statistical Area
                               l Kilometers
           0  5 10   20   30   40   50
           Q/\
              r
            2005 Population Density
            |    | Atlanta PMio Monitors (15 km buffer)
            Population per Sq Km
            ^H °-89
            ^B 90-177
                 178-886
                 887-1772
                 1773-4431
               • 4432-17722
           0  15 30    60   90   120  150
                                  : Kilometers
    Figure A-2.    PMio monitor distribution in comparison with population density, Atlanta, GA.
    December 2009
    A-60
    

    -------
                   Birmingham Combined Statistical Area
           0  5  10    20    30    40    50
           01
                                    ] Kilometers
         2005 Population Density
             | Birmingham PIVb.s Monitors (15 km buffer)
         Population per Sq Km
         ^^| 4-23
              24-47
              48 - 235
            | 236-469
            | 470-1173
            I 1174-4692
           0  15 30     60    90    120   150
                                      ] Kilometers
    Figure A-3.    PM2.s monitor distribution in comparison with population density, Birmingham,
                 AL
    December 2009
    A-61
    

    -------
                   Birmingham Combined  Statistical Area
           0  5  10    20    30   40   50
           01
                                    ] Kilometers
         2005 Population Density
             | Birmingham PMio Monitors (15 km buffer)
         Population per Sq Km
         ^^| 4-23
              24-47
              48 - 235
            | 236-469
            | 470-1173
            I 1174-4692
           0 15 30    60    90    120   150
                                      ] Kilometers
    Figure A-4.    PM10 monitor distribution in comparison with population density, Birmingham,
                 AL
    December 2009
    A-62
    

    -------
                       Boston Combined Statistical Area
                             ] Kilometers
           0 5 10  20  30  40  50
             A
                               : Kilometers
           0 15 30   60   90  120  150
          2005 Population Density
          |    || Boston PM2.5 Monitors (15km buffer)
          Population per Sq Km
          ^H 0-251
          H252 - 5°2
               503 - 2508
               2509-5016
               5017-12539
          ^B 12540-50155
    Figure A-5.    PM2.s monitor distribution in comparison with population density, Boston, MA.
    December 2009
    A-63
    

    -------
                       Boston Combined Statistical Area
                             ] Kilometers
           0 5 10  20  30  40  50
             A
           01
          2005 Population Density
          |    || Boston PM-io Monitors (15 km buffer)
          Population per Sq Km
          ^H 0-251
               252 - 502
               503 - 2508
               2509-5016
               5017-12539
          ^B 12540-50155
                               : Kilometers
           0 15 30   60   90  120  150
    Figure A-6.    PM10 monitor distribution in comparison with population density, Boston, MA.
    December 2009
    A-64
    

    -------
                      Chicago Combined Statistical Area
                              ] Kilometers
           0 5 10  20  30  40   50
                                                    2005 Population Density
                                                        | Chicago PIVh.s Monitors (15 km buffer)
                                                    Population per Sq Km
                                                    ^B ° - 22°
                                                        221 - 441
                                                       | 442 - 2204
                                                        2205 - 4407
                                                        4408-11019
                                                       I 11020-44074
           0 15 30   60   90   120   150
                                    ] Kilometers
    Figure A-7.    PM2.s monitor distribution in comparison with population density, Chicago, IL.
    December 2009
    A-65
    

    -------
                     Chicago Combined Statistical Area
                              ] Kilometers
           0  5 10   20   30  40  50
                                                  2005 Population Density
                                                      | Chicago PMio Monitors (15 km buffer)
                                                  Population per Sq Km
                                                  ^B ° - 22°
                                                  ^B221 -441
                                                       442 - 2204
                                                       2205 - 4407
                                                       4408-11019
                                                      I 11020-44074
           0  15 30    60    90   120   150
                                   ] Kilometers
    Figure A-8.    PMio monitor distribution in comparison with population density, Chicago, IL.
    December 2009
    A-66
    

    -------
                      Denver Combined Statistical Area
                              : Kilometers
           0  5 10  20  30  40   50
                                                    2005 Population Density
                                                    ^^ Denver PIVh.s Monitors (15 km buffer)
                                                    Population per Sq Km
                                                    ^B °-67
                                                    ^B 33-135
                                                         136-673
                                                         674-1347
                                                       | 1348-3364
                                                       I 3365-13456
                               : Kilometers
           0  15 30   60   90  120  150
    Figure A-9.    PM2.s monitor distribution in comparison with population density, Denver, CO.
    December 2009
    A-67
    

    -------
                      Denver Combined Statistical Area
                              : Kilometers
           0  5 10  20  30   40   50
                                                    2005 Population Density
                                                    	 Denver PMio Monitors (15km buffer)
                                                    Population per Sq Km
                                                    ^B °-67
                                                    ^B 68-135
                                                       | 136-673
                                                         674-1347
                                                       | 1348-3364
                                                       I 3365-13456
                               : Kilometers
           0 15 30  60   90  120  150
    Figure A-10.   PMio monitor distribution in comparison with population density, Denver, CO.
    December 2009
    A-68
    

    -------
                       Detroit Combined Statistical Area
           0 5 10   20   30   40   50
                                 : Kilometers
           Ql\
              r
            2005 Population Density
            ^^ Detroit PM2.5 Monitors (15 km buffer)
            Population per Sq Km
            ^B °-164
            ^B 135-327
                | 328-1637
                 1638-3274
                | 3275-8185
                I 8186-32741
           0 15 30    60    90    120    150
                                      : Kilometers
    Figure A-11.   PM2.s monitor distribution in comparison with population density, Detroit, Ml.
    December 2009
    A-69
    

    -------
                       Detroit Combined Statistical Area
           0 5 10   20   30   40   50
                                 : Kilometers
           Q/\
              r
            2005 Population Density
            |     Detroit PMio Monitors (15 km buffer)
            Population per Sq Km
            ^B °-164
            ^B 165-327
                 328-1637
                 1638-3274
                 3275-8185
                 8186-32741
           0 15 30    60    90    120    150
                                      ] Kilometers
    Figure A-12.   PMio monitor distribution in comparison with population density, Detroit, Ml.
    December 2009
    A-70
    

    -------
                      Houston Combined Statistical Area
           0  5 10   20    30    40    50
                                   ] Kilometers
           Q/\
              r
            2005 Population Density
            |     Houston PMz5 Monitors (15 km buffer)
            Population per Sq Km
            |^B 0-132
            JH 183-364
                 365-1822
                 1823-3644
                 3645-9109
               I 9110-36435
                              ] Kilometers
           0 1530  60   90  120  150
    Figure A-13.   PM2.s monitor distribution in comparison with population density, Houston, TX.
    December 2009
    A-71
    

    -------
                      Houston Combined Statistical Area
           0  5 10   20    30    40   50
           Q/\
              r
                                   ] Kilometers
            2005 Population Density
            |     Houston PMio Monitors (15 km buffer)
            Population per Sq Km
            |^B 0-132
            JH 183-364
                 365-1822
                 1823-3644
                 3645-9109
               I 9110-36435
                              ] Kilometers
           0 1530  60   90  120  150
    Figure A-14.   PMio monitor distribution in comparison with population density, Houston, TX.
    December 2009
    A-72
    

    -------
                  Los Angeles Core Based Statistical Area
           0  5  10
             A
                                        ] Kilometers
                            30     40     50
            2005 Population Density
                || Los Angeles PMzs Monitors (15 km buffer)
            Population per Sq Km
            ^Bl °-271
            ^H 272 - 542
                 543-2711
                 2712-5422
                 5423-13556
                 13557-54222
           0  15  30     60     90     120    150
                                         ] Kilometers
    Figure A-15.   PM2.s monitor distribution in comparison with population density, Los Angeles,
                 CA.
    December 2009
    A-73
    

    -------
                  Los Angeles Core Based Statistical Area
           0  5  10
                                        ] Kilometers
                            30     40     50
                                                    2005 Population Density
                                                        || Los Angeles PMio Monitors (15km buffer)
                                                    Population per Sq Km
                                                    ^Bl °-271
                                                    ^H 272 - 542
                                                         543-2711
                                                         2712-5422
                                                         5423-13556
                                                         13557-54222
           0  15  30     60     90     120    150
                                         ] Kilometers
    Figure A-16.   PM10 monitor distribution in comparison with population density, Los Angeles,
                 CA.
    December 2009
    A-74
    

    -------
                     New York Combined Statistical Area
                           : Kilometers
           0 5 10  20  30  40  50
                                                    2005 Population Density
                                                        || New York PM2.5 Monitors (15 km buffer)
                                                    Population per Sq Km
                                                    ^Bl ° -832
                                                    ^H 833-1664
                                                         1665-8319
                                                         8320-16637
                                                         16638-41593
                                                         41594-166371
                            ] Kilometers
           0 1530  60  90 120  150
    Figure A-17.   PM2.s monitor distribution in comparison with population density, New York, NY.
    December 2009
    A-75
    

    -------
                     New York Combined Statistical Area
                            : Kilometers
           0 5 10 20  30  40  50
                                                   2005 Population Density
                                                   [|    | New York PMio Monitors (15 km buffer)
                                                   Population per Sq Km
                                                   ^B ° -S32
                                                   ^B 833-1664
                                                       | 1665-8319
                                                        8320 -16637
                                                   ^B 16638-41593
                                                       • 41594-166371
                             ] Kilometers
           0 1530  60  90 120  150
    Figure A-18.   PM10 monitor distribution in comparison with population density, New York, NY.
    December 2009
    A-76
    

    -------
                    Philadelphia Combined  Statistical Area
                                             i Kilometers
           0   5   10
                        20     30
                                     40
                                            50
                                                     2005 Population Density
                                                     |    | Philadelphia PIVh.s Monitors (15 km buffer)
                                                     Population per Sq Km
                                                     ^B 0-133
                                                     ^B 184-366
                                                          367-1829
                                                          1830-3658
                                                          3659 - 9144
                                                     ^H 9145-36577
           0  15  30    60     90    120   150
                                       ] Kilometers
    Figure A-19.   PM2.s monitor distribution in comparison with population density, Philadelphia,
                 PA.
    December 2009
    A-77
    

    -------
                   Philadelphia Combined Statistical Area
           0   5   10     20     30     40     50
                                            i Kilometers
                                                     2005 Population Density
                                                     |    | Philadelphia PMio Monitors (15 km buffer)
                                                     Population per Sq Km
                                                     ^B 0-133
                                                     ^B 184-366
                                                          367-1829
                                                          1830-3658
                                                          3659 - 9144
                                                     ^H 9145-36577
           0  15 30    60     90    120   150
                                       ] Kilometers
    Figure A-20.   PM10 monitor distribution in comparison with population density, Philadelphia,
                 PA.
    December 2009
    A-78
    

    -------
                     Phoenix Core  Based Statistical Area
           0 5 10   20   30   40   50
                                 ] Kilometers
                                                      2005 Population Density
                                                          | Phoenix PIVhs Monitors (15 km buffer)
                                                      Population per Sq Km
                                                           81 -159
                                                           160-795
                                                           796-1591
                                                           1592-3977
                                                           3978-15907
                               : Kilometers
           0 15 30  60   90  120  150
    Figure A-21.   PM2.s monitor distribution in comparison with population density, Phoenix, AZ.
    December 2009
    A-79
    

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                     Phoenix Core Based Statistical Area
           0  5 10   20   30   40    50
                                 ] Kilometers
                                                      2005 Population Density
                                                          | Phoenix PMio Monitors (15 km buffer)
                                                      Population per Sq Km
                                                           0-80
                                                      ^B 81 ~159
                                                         | 160-795
                                                           796-1591
                                                           1592-3977
                                                         I 3978-15907
                               : Kilometers
           0  15 30  60  90  120  150
    Figure A-22.   PM™ monitor distribution in comparison with population density, Phoenix, AZ.
    December 2009
    A-80
    

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                     Pittsburgh Combined Statistical Area
           0  5  10     20     30     40     50
           Ql\
              r
                                           ] Kilometers
          2005 Population Density
          [     | Pittsburgh PIVh.s Monitors (15 km buffer)
          Population per Sq Km
          ^B 6 -204
               205 - 409
             | 410-2045
               2046 - 4090
               4091 -10225
             I 10226-40898
           0  15  30     60     90     120     150
                                           l Kilometers
    Figure A-23.   PM2.s monitor distribution in comparison with population density, Pittsburgh, PA.
    December 2009
    A-81
    

    -------
                     Pittsburgh Combined  Statistical Area
                                           ] Kilometers
           0  5  10     20     30     40
                                          50
           Ql\
              r
          2005 Population Density
          	 Pittsburgh PMio Monitors (15 km buffer)
          Population per Sq Km
          ^B 6 -204
               205 - 409
             | 410-2045
               2046 - 4090
               4091 -10225
             I 10226-40898
           0  15  30     60     90     120    150
                                           : Kilometers
    Figure A-24.   PM™ monitor distribution in comparison with population density, Pittsburgh, PA.
    December 2009
    A-82
    

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                    Riverside Core Based Statistical Area
                           ] Kilometers
           0510  20 30  40  50
                            ] Kilometers
           0 1530  60  90  120 150
                                                       2005 Population Density
                                                           | Riverside PMzs Monitors (15 km buffer)
                                                       Population per Sq Km
                                                            0-89
                                                       ^B 90-178
                                                          | 179-892
                                                            893-1784
                                                          | 1785-4460
                                                          • 4461 -17838
    Figure A-25.   PM2.s monitor distribution in comparison with population density, Riverside, CA.
    December 2009
    A-83
    

    -------
                    Riverside Core Based  Statistical Area
                           ] Kilometers
           0510  20  30  40  50
                         : Kilometers
           012.95 50  75 100 125
                                                       2005 Population Density
                                                           | Riverside PMio Monitors (15 km buffer)
                                                       Population per Sq Km
                                                            0-89
                                                       ^B 90-178
                                                          | 179-892
                                                            893-1784
                                                          | 1785-4460
                                                          • 4461 -17838
    Figure A-26.   PM™ monitor distribution in comparison with population density, Riverside, CA.
    December 2009
    A-84
    

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                       Seattle  Combined Statistical Area
                               : Kilometers
           0 5 10   20   30   40   50
                                                     2005 Population Density
                                                         |j Seattle PIVh.s Monitors (15km buffer)
                                                     Population per Sq Km
                                                          0-120
                                                          121-240
                                                          241 -1201
                                                          1202-2402
                                                          2403 - 6006
                                                          6007 - 24022
           0 15 30   60    90   120   150
                                  l Kilometers
    Figure A-27.   PM2.s monitor distribution in comparison with population density, Seattle, WA.
    December 2009
    A-85
    

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                      Seattle Combined Statistical Area
                              : Kilometers
           0  5 10  20  30   40   50
                                                    2005 Population Density
                                                    [|    |] Seattle PMio Monitors (15 km buffer)
                                                    Population per Sq Km
                                                    ^m 0-120
                                                    ^B 121 ~24°
                                                         241 -1201
                                                         1202-2402
                                                         2403 - 6006
                                                    ^H 6007 - 24022
           0  15 30   60   90   120   150
                                  l Kilometers
    Figure A-28.   PMio monitor distribution in comparison with population density, Seattle, WA.
    December 2009
    A-86
    

    -------
                         St. Louis Combined  Statistical Area
              0 5 10   20   30   40   50
                                    : Kilometers
                                                       2005 Population Density
                                                           | StLouis PM2.5 Monitors (15 km buffer)
                                                       Population per Sq Km
                                                       ^B °-54
                                                       ^B 55-109
                                                            110-544
                                                            545-1088
                                                          | 1089-2720
                                                          • 2721 -10878
              0 15  30   60   90    120  150
                                      : Kilometers
    Figure A-29.   PM2.s monitor distribution in comparison with population density, St. Louis, MO.
    December 2009
    A-87
    

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                      St. Louis Combined Statistical Area
           0  5 10   20   30   40   50
                                 l Kilometers
                                                     2005 Population Density
                                                         | StLouis PMio Monitors (15 km buffer)
                                                     Population per Sq Km
                                                          0-54
                                                          55-109
                                                          110-544
                                                          545-1088
                                                          1089-2720
                                                          2721 -10878
           0  15 30   60   90    120   150
                                   : Kilometers
    Figure A-30.   PM™ monitor distribution in comparison with population density, St. Louis, MO.
    December 2009
    A-88
    

    -------
    A.2.  Ambient PM Concentration
    A.2.1.  Speciation Trends Network Site Data
                                      Copper - Annual
                        copper(ug/m3): <=0.002  >0.002 to 0.004   >0.004 to 0.006  >0.006-0.008   >0.008
                        Copper - Spring
             r.-;-ip-r(i -,'i.' ~i) =r nn;  n •in; tr. n c J4
                                                        Copper - Summer
                        Copper -
                                                     O     «   «s
                                                           • Jj^r
    Figure A-31.  Three-yr avg of 24-h PM2.s Cu concentrations measured at CSN sites across the
    
                U.S., 2005-2007.
    December 2009
    A-89
    

    -------
                                                     Iron  -  Annual
                          ron(ug/m3):  <=0.05       >0.05 to 0.075        >0.075 to 0.1       >0.1-0.125        >0.126
                            Iron ~~ SpnnQ
                       0 05 to 0.075      >0.075toO 1
                                             •
    
                                             >Q.1-0.125
                                                                                   Iron ~ Summer
                                                                                                             r\
                                                                •
                                                                                                           *
                                                                                                        °-
                                                                              V
                              •^ M^H  ~*  »   -^' N.  \
                                 ^f^
                                               V
                                   o          •       •
                                   >0.075to0.1      >0.1-0.125      >0.125
                             Iron - Fall
                                                                                   Iran  - Winter
        ron(ug/m3): <=0.05     >0.05 to 0.075      >0.075 to 0.1     >0 1-0.125     >0.125
    Figure A-32.    Three-yr avg of 24-h PM2.s Fe concentrations measured at CSN sites across the
                      U.S., 2005-2007
    December  2009
    A-90
    

    -------
                                                              Ni  -  Annual
                              Nickel(ug/m3):  <=0.0005    >0.0005 to 0.001      >0.001 to 0.0015     >0.0015-0.002     >0.002
                               NI -  Spring
       Nickel(ug/m3): <=00005    >O.ODD5toD 001    >0.001 to 0.0015    >00015-0.002    >0 002
                                                                      Nickd(ug/m3): <=0.0005    >0.0005 toO.001    >0001to00015    >0.0015-O.D02    >O.D02
                                NI -
                                                                                              NI - Winter
                                                              0
                oo           o           •
    
       Nlckd(ug/m3): <-0.0005    >0 0005 too.001    >0.001 to 0.0015    >O.D015-0002
                 .o           C           •         •
    
        Nlckel(og/m3).  <-0.0005    >0 0005 to 0.001     >0.001 to 0.0015    >0.0015-0002    >0 002
    Figure A-33.    Three-yr avg of 24-h PM2.s Ni concentrations measured at CSN sites across the
                        U.S., 2005-2007
    December  2009
    A-91
    

    -------
                                                        Lead  -  Annual
                            Lead(ug/m3): <=0.005        >0.005to0.01
                                                                    O
    
                                                                   >0.01 to 0.015
                            Lead -  Spring
       Leadfug/tTi3).  <=0005      >O.OQ5 to 0.01      >Q.Q1 to 0.015     >0 015-0.02     sO.02
                                                                                      Lead  - Summer
                                                                  Lead(ug/m3).  <=QB05      >O.Q05 to D 01      s001 to 0.015     >0015-0 02
                             Lead  - Fall
                                                                                       Lead - Winter
       Lead(ug/m3):  <=0.005      >0.005to0.01      >OD1 to 0.015     >0.015-0.02
                                                                  Lead(ug/m3).  <=Q 005      >O.OD5 to 0.01      >0 01 to 0.015     >0.015-0 02
    Figure A-34.    Three-yr avg of 24-h  PM2.s Pb concentrations measured at CSN sites across the
                       U.S., 2005-2007
    December 2009
    A-92
    

    -------
                                                         Selenium  -  Annual
                                Selenium(ug/m3):  <=0.001     >0.001 to 0.002     >0.002 to 0.003     >0.003-0.004     >0.004
                              Selenium  - Spring
           Selenium (ug/mS)1  <=O.OQ1   >0 001 to 0.002   >O.OD2 to D 003   >0 003-0 004   >0.004
                               Selenium - Fail
           Selemum(ug/m3)  <=D.DD1   >OOQ1toD.OD2    >D.DD2toOD03   SO 003-0 004   >O.OM
                                                                                       Selenium  - Summer
                                                                     Łide''ijrn(ug,'m3):  <=0 001   >0 001 to 0.002    >0 002 to OJ303   >O.OD3-0.004    >O.D04
                                                                                        Selenium  — Winter
                                                                          (uq/m3):  <=0.001   >0.001 to 0.002    >O.D02 to 0003   >0 003-0 004    >0.004
    Figure A-35.    Three-yr avg of 24-h  PM2.s Se concentrations measured at CSN sites across the
                       U.S., 2005-2007
    December  2009
    A-93
    

    -------
                                                      vanadium   - Annual
                               Vanadium(ug/m3):  <=0.004    »0.004 to 0.006      »0.006 to 0.008     >0.008-0.01     >0.01
                           vanadium  - Spring
         Vanadium (ug/in 3)-  <=0.004   >OOQ4tO 0.006    >0.006to 0.008   >0 008-0.01    >0.01
                                                                                     Vanadium  - Summer
                                                                    V:-.na Jiurr, ^gym 3)  <=Q.Q04    >Q.OQ4 to 0.006    >0 006 to 0 I
                            Vanadium  - Fall
                                                                                      Vanadium  - Winter
         Vanadium(ug/m3):  <=0.004   >0.004to 0.006    >0.006to 0.008   >O.OOS-0 01    >O.D1
                                                                                     3           o         •        •
                                                                                      >0.004tO 0.006    >0.006tO 0 008    >0.000-0.01   >0.01
    Figure A-36.    Three-yr avg of 24-h PM2.s V concentrations measured at CSN sites across the
                       U.S., 2005-2007
    December 2009
    A-94
    

    -------
    A.2.2.  Intraurban Variability
          The following figures and tables exemplify the intraurban variability among PM2.5, PMi0_2.5
    and PMio measurements for select CSAs/CBSAs (2005-2007) including Atlanta, Birmingham,
    Chicago, Denver, Detroit, Houston, New York City, Philadelphia, Phoenix, Riverside, Seattle and St.
    Louis. Maps are included to show monitor locations relative to major roadways. Box plots show the
    median and interquartile range of concentrations with whiskers extending to the 5th and 95th
    percentiles at each site during (1) winter (December-February); (2) spring (March-May); (3) summer
    (June-August); and (4) fall (September-November). Tables of inter-sampler comparison statistics and
    scatter plots of inter-sampler correlation vs. distance illustrate variability present in each area.
    December 2009                                 A-95
    

    -------
                      Atlanta Combined  Statistical Area
            A
          01
                           Atlanta CSA
                        •  PM2 5 Monitors
                        	 Interstate Highways
                          - Major Highways
                                       0  10  20     40     60     80
                                100
                                —i Kilometers
    Figure A-37.  PM2.s monitor distribution and major highways, Atlanta, GA.
    December 2009
    A-96
    

    -------
          Site A
          SiteB
          SiteC
          SiteD
          SiteE
          SiteF
          SiteG
          SiteH
          Site I
    13-063-0091
    13-067-0003
    13-067-0004
    13-089-0002
    13-089-2001
    13-121-0032
    13-135-0002
    13-139-0003
    13-223-0003
    AB CDEFG H
    Mean 16.2 16.2 15.4 15.3 15.2 15.7 15.2 13.9 14.4
    Obs 351 352 339 1014 946 1036 221 336 344
    SD 7.5 7.9 7.7 7.2 7.6 8.2 7.1 6.9 7.6
    40 -
    30-
    20 -
    10-
    o -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                          Ol
    
                          c
                          o
                          4-*
                          ro
                          •*-*
                          C
                          u
                          c
                          o
                     1=winter
                     2=spring
                     3=summer
                     4=fall          1234  1234  1234  1234  1234  1234 1234   1234 1234
    Figure A-38.   Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                    for Atlanta, GA.
    December 2009
                                          A-97
    

    -------
    Table A-20. Inter-sampler correlation statistics for each
    Atlanta, GA.
    A B C D
    A 1.00 0.88 0.87 0.93
    (0.0,0.00) (5.2,0.11) (6.2,0.12) (3.9,0.11)
    351 330 310 330
    B 1.00 0.96 0.89
    (0.0,0.00) (4.1,0.08) (5.7,0.12)
    352 309 327
    C 1.00 0.87
    (0.0,0.00) (5.2,0.12)
    339 315
    D 1.00
    (0.0, 0.00)
    1014
    E
    
    LEGEND
    F R
    (P90, COD)
    N
    G
    
    
    H
    
    
    I
    E
    0.89
    (5.3,0.12)
    315
    0.88
    (4.6,0.10)
    314
    0.86
    (5.6,0.11)
    304
    0.89
    (4.8,0.12)
    883
    1.00
    (0.0, 0.00)
    946
    
    
    
    
    
    
    
    
    
    
    pair of PM2.6 monitors reporting to AQS for
    F
    0.91
    (4.6,0.11)
    334
    0.91
    (3.6, 0.08)
    333
    0.88
    (4.4,0.10)
    324
    0.80
    (3.7,0.11)
    978
    0.79
    (3.8,0.11)
    904
    1.00
    (0.0, 0.00)
    1036
    
    
    
    
    
    
    
    G
    0.85
    (6.9,0.15)
    207
    0.88
    (5.6,0.13)
    205
    0.85
    (5.8,0.13)
    193
    0.87
    (5.8,0.13)
    208
    0.88
    (5.3,0.12)
    208
    0.88
    (5.3,0.12)
    213
    1.00
    (0.0, 0.00)
    221
    
    
    
    
    H
    0.72
    (8.7,0.19)
    319
    0.78
    (9.0,0.17)
    313
    0.79
    (7.9,0.17)
    298
    0.74
    (8.3,0.18)
    314
    0.74
    (7.8,0.17)
    305
    0.70
    (8.5,0.19)
    321
    0.73
    (8.8,0.17)
    195
    1.00
    (0.0, 0.00)
    336
    
    I
    0.85
    (7.2,0.15)
    326
    0.88
    (6.5,0.13)
    321
    0.90
    (4.5,0.11)
    303
    0.82
    (7.3,0.15)
    322
    0.83
    (6.4,0.14)
    309
    0.84
    (6.3,0.14)
    327
    0.79
    (7.4,0.15)
    198
    0.76
    (8.7,0.17)
    309
    1.00
    (0.0, 0.00)
    344
    December 2009                                       A-98
    

    -------
        1.00 -
        0.80
        0.60
      o
    
      13
      o
      O
        0.40
        0.20
                              •**•*<•**?*     ^
        0.00
                    10       20        30
                                              40       50       60
    
                                            Distance Between Samplers (km)
                                                                         70       80       90       100
    Figure A-39.   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                   Atlanta, GA.
    December 2009
    A-99
    

    -------
                  Birmingham Combined  Statistical Area
            A
          01
                            Birmingham CSA
                         •  PM2.5 Monitors
                         	 Interstate Highways
                          — Major Highways
                                    0  10  20     40     60     80
                              100
                              —i Kilometers
    Figure A-40.  PM2.s monitor distribution and major highways, Birmingham, AL.
    December 2009
    A-100
    

    -------
    
    Site A
    SiteB
    SiteC
    SiteD
    SiteE
    SiteF
    SiteG
    SiteH
    Sitel
    SiteJ
    AQS Site ID
    01-073-0023
    01-073-1005
    01-073-1009
    01-073-1010
    01-073-2003
    01-073-2006
    01-073-5002
    01-073-5003
    01-117-0006
    01-127-0002
    A
    
    Mean 18.9
    Obs 1087
    SD 102
    50 -
    
    
    
    40 -
    
    
    
    
    
    
    
                    c
                    o
                      30 -
                      20 -
                    c
                    01
                    u
                    c
                    o
                    u
                      10 -
               1=winter
    
               2=spring
    
               3=summer 0 -
    
               4=fall
    ABCDEFGH J
    18.9 15.9 14.1 16.2 17.7 15.4 14.8 14.9 14.6 14.4
    1087 363 359 182 1079 364 363 360 361 351
    10.2 8.2 8.2 8.1 9.4 7.8 7.9 8.3 7.6 7.5
    
    
    
    
    
    
    
    
                          1234  1234 1234  1234  1234  1234  1234  1234  1234  1234
    Figure A-41.   Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
    
                 for Birmingham, AL
    December 2009
    A-101
    

    -------
    Table A-21 . Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
    Birmingham, AL
    ABC
    A 1.00 0.91 0.86
    (0.0,0.00) (10.4,0.15) (13.7,0.21)
    1087 360 356
    B 1.00 0.93
    (0.0,0.00) (5.3,0.12)
    363 356
    C 1.00
    (0.0, 0.00)
    359
    D
    
    
    E
    
    LEGEND
    F R
    (P90, COD)
    N
    G
    
    
    H
    
    
    I
    
    
    J
    D E F
    0.91 0.88 0.91
    (9.7,0.13) (8.1,0.13) (10.8,0.15)
    182 1072 361
    0.93 0.85 0.96
    (4.7,0.09) (8.3,0.15) (3.6,0.08)
    181 359 358
    0.93 0.81 0.93
    (5.9,0.13) (10.1,0.20) (4.6,0.12)
    180 355 354
    1.00 0.88 0.96
    (0.0,0.00) (7.9,0.12) (3.6,0.08)
    182 179 179
    1.00 0.87
    (0.0,0.00) (8.1,0.15)
    1079 360
    1.00
    (0.0, 0.00)
    364
    
    
    
    
    
    
    
    
    
    
    G
    0.87
    (12.6,0.18)
    360
    0.91
    (5.4,0.11)
    360
    0.91
    (4.3,0.12)
    355
    0.95
    (3.8, 0.09)
    181
    0.85
    (8.7,0.16)
    359
    0.95
    (3.9, 0.09)
    359
    1.00
    (0.0, 0.00)
    363
    
    
    
    
    
    
    
    H
    0.88
    (11.7,0.18)
    357
    0.93
    (5.1,0.11)
    355
    0.94
    (4.0,0.10)
    350
    0.95
    (4.7,0.10)
    179
    0.85
    (8.8,0.17)
    356
    0.95
    (4.1,0.10)
    354
    0.96
    (3.3, 0.08)
    356
    1.00
    (0.0, 0.00)
    360
    
    
    
    
    I
    0.88
    (12.3,0.18)
    358
    0.93
    (4.9,0.10)
    358
    0.90
    (4.9,0.12)
    353
    0.93
    (4.7,0.10)
    180
    0.86
    (9.2,0.16)
    357
    0.95
    (3.4, 0.09)
    357
    0.92
    (4.5,0.10)
    359
    0.91
    (5.0,0.11)
    354
    1.00
    (0.0, 0.00)
    361
    
    J
    0.84
    (12.5,0.19)
    348
    0.89
    (6.1,0.12)
    348
    0.90
    (4.9,0.11)
    343
    0.89
    (6.1,0.12)
    174
    0.81
    (10.6,0.18)
    347
    0.90
    (5.6,0.11)
    348
    0.89
    (4.9,0.11)
    350
    0.93
    (4.3, 0.09)
    344
    0.87
    (5.8,0.12)
    349
    1.00
    (0.0, 0.00)
    351
    December 2009                                      A-102
    

    -------
        1.00
        0.80
                                                   * » * »               »
                                               A    A   •   •       4
                                               *    *        »   »   *       »
        0.60
      o
      13
      o
      O
        0.40
        0.20
        0.00
                    10       20       30       40       50       60
                                            Distance Between Samplers (km)
                                                                       70       80       90       100
    Figure A-42.   PM2.s inter-sampler correlations as a function of distance between monitors for
                   Birmingham, AL
    December 2009
    A-103
    

    -------
                      Boston Combined Statistical Area
          01
             r
                          Boston CSA
                       •  PM2 5 Monitors
                       	 Interstate Highways
                         — Major Highways
                                          0  10  20    40    60    80
                                100
                                —i Kilometers
    Figure A-43.  PM2.s monitor distribution and major highways, Boston, MA.
    December 2009
    A-104
    

    -------
    
    SiteA
    SteB
    SteC
    SteD
    SteE
    SiteF
    SiteG
    SiteH
    Shel
    ShseJ
    AQS Site ID
    25-005-1004
    25-009-2006
    25-009-5005
    25-009-6001
    25-023-0004
    25-025-0002
    25-025-0027
    25-025-0042
    25-025-0043
    25-027-0016
                    1 -winter
                    2-spring
                    3=summer
                    4=fall
    SrtEK
    SiteL
    SiteM
    SiteN
    Sited
    SrteP
    SiteQ
    SiteR
    SteS
    AQS Site ID
    25-027-0023
    33-001-2004
    33-011-1015
    33-013-1006
    33-015-0014
    44-007-0022
    44-007-0026
    44-007-0028
    44-007-1010
    A B C D E F G H J
    Ivtean 9.1 9.1 8.9 9.4 9.6 11.7 11.6 10.5 12.1 10.7
    Obs 341 350 342 355 357 349 398 349 1015 335
    SO
    40-
    ST- 30~
    Ol
    a.
    c
    o
    ro 20-
    concenti
    10-
    
    o -
    6.0 6.5 6.3 6.6 6.6 7.0 6.8 6.9 6.9 7.2
    
    
    
    
    
    
    1 1 1
    ' ill i 'I' 1 I
    
    
    
    
    
    
    
    
    
    
                                  1234 1234 1234  1234 1234  1234 1234  1234 1234  1234
                     4=fall
    K L
    Mean 11.4 7.2
    Obs 346 183
    SD
    40-
    __. 30-
    c
    o
    4_t 7 n —
    concentra
    lo-
    iter
    ing
    Timer
    0 -
    7.4 5.3
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    1
    |
    
    
    
    
    M N O P Q R S
    10.0 9.7 8.9 10.1 11.9 10.5 9.7
    361 362 362 1027 321 313 998
    6.7 6.0 5.8 6.6 6.9 6.5 6.5
    
    
    
    1
    
    '1
    
    
    
    
    
    
    1
    !
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                1234  1234  1234  1234  1234  1234 1234 1234 1234
    Figure A-44.   Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                   for Boston, MA.
    December 2009
    A-105
    

    -------
    Table A-22.   Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
                 Boston, MA.
    Site
    A
    
    
    B
    A
    1.00
    (0.0, 0.00) (6J
    341
    
    B
    0.80
    6,0.21)
    326
    1.00
    (0.0, 0.00)
    
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    1
    
    
    J
    
    
    
    
    LEGEND
    Pearson R
    (P90, COD)
    n
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    350
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    C D
    0.77 0.71
    (6.2, 0.22) (6.9, 0.23)
    318 323
    0.92 0.87
    (4.1,0.17) (4.1,0.18)
    328 331
    1.00 0.90
    (0.0,0.00) (3.5,0.17)
    342 321
    1.00
    (0.0, 0.00)
    355
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    E
    0.84
    (4.8,0.19)
    329
    0.87
    (4.7,0.19)
    339
    0.85
    (5.3,0.21)
    331
    0.80
    (5.6, 0.20)
    336
    1.00
    (0.0, 0.00)
    357
    
    
    
    
    
    
    
    
    
    
    
    
    
    F
    0.79
    (8.1,0.23)
    318
    0.90
    (6.3,0.21)
    326
    0.90
    (6.3, 0.23)
    316
    0.88
    (5.8,0.21)
    324
    0.90
    (5.9,0.19)
    330
    1.00
    (0.0, 0.00)
    349
    
    
    
    
    
    
    
    
    
    
    G
    0.78
    (7.7, 0.24)
    319
    0.90
    (6.2, 0.23)
    323
    0.89
    (6.3, 0.24)
    318
    0.88
    (5.8, 0.22)
    329
    0.90
    (5.8,0.21)
    333
    0.94
    (3.8,0.14)
    324
    1.00
    (0.0, 0.00)
    398
    
    
    
    
    
    
    
    H
    0.79
    (6.8, 0.22)
    325
    0.90
    (4.9,0.19)
    333
    0.90
    (5.0, 0.20)
    326
    0.86
    (4.6,0.19)
    332
    0.89
    (5.0,0.19)
    340
    0.94
    (3.5,0.15)
    324
    0.94
    (4.0,0.16)
    325
    1.00
    (0.0, 0.00)
    349
    
    
    
    
    1
    0.79
    (7.9, 0.25)
    338
    0.90
    (7.1,0.26)
    343
    0.88
    (6.8, 0.26)
    336
    0.86
    (7.0, 0.26)
    345
    0.87
    (6.9, 0.24)
    350
    0.92
    (4.5,0.17)
    339
    0.94
    (4.3,0.15)
    338
    0.93
    (4.7,0.19)
    342
    1.00
    (0.0, 0.00)
    1015
    
    J
    0.77
    (7.5, 0.24)
    310
    0.85
    (5.5,0.21)
    317
    0.86
    (6.2,0.21)
    311
    0.87
    (5.8,0.19)
    313
    0.87
    (5.4, 0.20)
    322
    0.92
    (5.4,0.18)
    310
    0.89
    (5.7, 0.20)
    308
    0.89
    (5.0,0.17)
    318
    0.86
    (6.9, 0.23)
    330
    1.00
    (0.0, 0.00)
    335
    
    Site
    A
    
    
    B
    
    
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    1
    
    
    J
    
    
    K
    
    
    L
    
    
    M
    
    
    N
    
    
    0
    
    
    P
    
    K
    077
    (8.1,0.23)
    320
    0.86
    (6.6,0.21)
    329
    0.86
    (6.9,0.21)
    321
    0.88
    (6.4,0.19)
    325
    0.87
    (6.3, 0.20)
    333
    0.91
    (4.7,0.17)
    323
    0.90
    (5.0,0.19)
    320
    0.90
    (4.4,0.17)
    327
    0.87
    (6.1,0.20)
    341
    0.95
    (3.0,0.14)
    316
    1.00
    (0.0, 0.00)
    346
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    L
    0.61
    (8.3, 0.29)
    173
    0.80
    (6.2, 0.23)
    175
    0.89
    (4.8, 0.23)
    173
    0.79
    (5.7, 0.25)
    174
    0.72
    (8.3, 0.27)
    179
    0.78
    (9.6, 0.33)
    168
    0.77
    (9.0, 0.33)
    172
    0.75
    (9.4, 0.30)
    175
    0.75
    (10.0,0.36)
    181
    0.73
    (9.2, 0.28)
    167
    0.71
    (10.3,0.31)
    170
    1.00
    (0.0, 0.00)
    183
    
    LEGEND
    Pearson R
    (P90, COD)
    n
    
    
    
    
    M
    0.71
    (8.0, 0.23)
    324
    0.87
    (5.3,0.19)
    331
    0.93
    (4.4,0.17)
    323
    0.91
    (3.5,0.16)
    329
    0.83
    (5.8,0.17)
    338
    0.90
    (5.3,0.18)
    323
    0.90
    (5.3,0.19)
    326
    0.88
    (4.9,0.18)
    332
    0.86
    (6.7, 0.22)
    352
    0.87
    (5.2,0.18)
    314
    0.88
    (6.0,0.16)
    326
    0.89
    (6.7, 0.24)
    176
    1.00
    (0.0, 0.00)
    361
    
    
    
    
    
    
    
    
    N
    0.68
    (7.9, 0.23)
    334
    0.83
    (6.0,0.21)
    341
    0.90
    (4.6,0.19)
    335
    0.85
    (4.7,0.19)
    339
    0.79
    (6.3, 0.20)
    347
    0.85
    (6.4, 0.20)
    334
    0.85
    (6.3, 0.20)
    335
    0.83
    (5.6,0.21)
    341
    0.82
    (7.2, 0.23)
    356
    0.84
    (5.9, 0.20)
    326
    0.85
    (6.5,0.19)
    337
    0.91
    (5.9, 0.23)
    181
    0.94
    (3.8,0.13)
    341
    1.00
    (0.0, 0.00)
    362
    
    
    
    
    
    0
    0.73
    (7.0, 0.22)
    331
    0.88
    (4.7,0.18)
    336
    0.93
    (3.8,0.18)
    328
    0.86
    (4.2,0.18)
    334
    0.84
    (4.8,0.18)
    343
    0.85
    (7.5, 0.22)
    330
    0.87
    (7.0, 0.22)
    329
    0.84
    (6.8,0.21)
    336
    0.83
    (8.2, 0.25)
    357
    0.80
    (7.5, 0.22)
    323
    0.81
    (8.2, 0.22)
    332
    0.90
    (4.8,0.21)
    177
    0.90
    (4.6,0.16)
    336
    0.90
    (4.4,0.17)
    346
    1.00
    (0.0, 0.00)
    362
    
    
    P
    0.87
    (5.3,0.18)
    326
    0.86
    (5.6,0.19)
    335
    0.83
    (5.9,0.21)
    329
    0.80
    (6.2, 0.20)
    342
    0.91
    (4.5,0.17)
    343
    0.89
    (5.2,0.16)
    336
    0.88
    (5.5,0.17)
    383
    0.89
    (4.5,0.16)
    335
    0.88
    (6.1,0.20)
    957
    0.90
    (5.0,0.17)
    321
    0.89
    (5.2,0.16)
    331
    0.68
    (10.0,0.29)
    181
    0.83
    (5.5,0.16)
    345
    0.77
    (6.7,0.19)
    347
    0.80
    (5.8,0.19)
    348
    1.00
    (0.0, 0.00)
    Q
    0.81
    (7.2, 0.23)
    292
    0.80
    (7.9, 0.26)
    300
    0.79
    (7.8, 0.26)
    290
    0.75
    (7.8, 0.25)
    300
    0.86
    (6.3, 0.22)
    306
    0.86
    (6.0,0.16)
    295
    0.86
    (5.3,0.17)
    296
    0.86
    (6.0,0.19)
    299
    0.84
    (6.0,0.16)
    314
    0.86
    (5.9, 0.20)
    283
    0.86
    (5.8,0.18)
    296
    0.63
    (12.1,0.35)
    153
    0.81
    (7.4, 0.20)
    300
    0.75
    (8.1,0.22)
    309
    0.75
    (8.8, 0.25)
    304
    0.95
    (3.6,0.14)
    R
    0.85
    (5.6, 0.20)
    285
    0.85
    (5.7,0.21)
    288
    0.81
    (6.2, 0.23)
    281
    0.79
    (6.2,0.21)
    287
    0.88
    (4.9,0.18)
    295
    0.88
    (4.9,0.16)
    281
    0.87
    (5.2,0.17)
    282
    0.87
    (4.5,0.16)
    289
    0.85
    (6.0,0.18)
    306
    0.87
    (5.3,0.17)
    272
    0.87
    (5.5,0.16)
    286
    0.72
    (9.1,0.30)
    149
    0.82
    (5.8,0.17)
    288
    0.78
    (6.4, 0.20)
    297
    0.79
    (6.8,0.21)
    292
    0.97
    (2.0, 0.09)
    S
    0.86
    (5.2,0.18)
    306
    0.85
    (6.0,0.19)
    314
    0.82
    (6.0,0.21)
    309
    0.80
    (5.8, 0.20)
    321
    0.91
    (3.9,0.17)
    324
    0.89
    (5.5,0.17)
    316
    0.88
    (5.7,0.19)
    356
    0.88
    (5.1,0.17)
    314
    0.87
    (6.3,0.21)
    936
    0.88
    (5.2,0.18)
    302
    0.88
    (5.5,0.18)
    313
    0.69
    (9.8, 0.29)
    164
    0.84
    (5.1,0.16)
    326
    0.78
    (6.2,0.19)
    327
    0.80
    (6.0,0.19)
    330
    0.97
    (2.1,0.08)
    December 2009
    A-106
    

    -------
                                                                         1027
                                                                                      307
                                                                                    (0.0, 0.00)
                                                                                                 299
                                                                                               (3.1,0.13)
                                                                                                            943
                                                                                                            0.94
                                                                                                          (4.0,0.16)
                                                                                                 268
                                                                                                            290
                                                                                                            0.94
                                                                                               (0.0, 0.00)
                                                                                                          (2.7,0.12)
                                                                                                            280
                                                                                                            1.00
                                                                                                          (0.0, 0.00)
                                                                                                            998
                     •
                     »
                                                           **   *
           0.8
           0.6
         o
         1
           0.4
           0.2
                       10       20        30        40       50        60
                                                 Distance Between Samplers (km)
                                                                               70
                                                                                                  90
                                                                                                           100
    Figure A-45.    PM2.s inter-sampler correlations as a function of distance between monitors for
                     Boston, MA.
    December 2009
    A-107
    

    -------
                     Chicago  Combined Statistical Area
            A
          01
                         Chicago CSA
                      •  PMz.s Monitors
                     	 Interstate Highways
                       — Major Highways
                                       0  10 20    40     60     80
                             100
                             —i Kilometers
    Figure A-46.  PM2.s monitor distribution and major highways, Chicago, IL
    December 2009
    A-108
    

    -------
           Site A
           SiteB
           SiteC
           SiteD
           SiteE
           SiteF
           SiteG
           SiteH
           Site I
           SiteJ
           SiteK
    AQS Site ID
    17-031-0022
    17-031-0050
    17-031-0052
    17-031-0057
    17-031-0076
    17-031-1016
    17-031-2001
    17-031-3103
    17-031-3301
    17-031-4007
    17-031-4201
                                       1234  1234   1234  1234  1234  1234  1234   1234  1234  1234  1234
    
    SiteL
    SiteM
    
    SiteN
    SiteO
    SiteP
    SiteQ
    SiteR
    SiteS
    Site!
    SiteU
    AQS Site ID L
    17-031-6005 Mean 151
    17-043-4002 ..
    Obs 331
    17-089-0003
    17-089-0007 8J
    17-097-1007 50 -
    17-111-0001
    17-197-1002
    17-197-1011
    18-089-0006 40 -
    18-089-0022
    
    
    
    
    
    
          Dl
    
          C
          O
          4-»
          ro
          •*-*
          c
          u
          c
          o
                  1=winter
                  2=spring
                  3=summer
                  4=fall
                              30 -
                              20 -
                              10 -
                 0  -
    LMNOPQRSTU
    i 15.1 14.0 13.5 14.3 12.1 12.3 14.0 11.7 14.4 15.6
    3 331 179 176 174 181 347 175 164 330 351
    1 8.7 8.5 8.5 8.9 8.2 7.5 8.5 7.2 7.7 8.2
    
    
    
    
    
    
    
    
    
    
    
    
                                     1234   1234   1234  1234   1234  1234   1234   1234  1234   1234
    December 2009
                                                    A-109
    

    -------
    SiteV
    SiteW
    SiteX
    SiteY
    SiteZ
    Site AA
    Site AB
    Site AC
    Site AD
    Site AE
    AQS Site ID
    18-089-0026
    18-089-0027
    18-089-1003
    18-089-2004
    18-089-2010
    18-091-0011
    18-091-0012
    18-127-0020
    18-127-0024
    55-059-0019
                            1234   1234  1234   1234  1234  1234  1234  1234   1234  1234
    Figure A-47.   Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                    for Chicago, IL
    December 2009
                                              A-110
    

    -------
    Table A-23.   Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
                 Chicago, IL.
    A B C D
    A 1.00 0.98 0.93 0.94
    (0.0,0.00) (3.1,0.08) (5.5,0.12) (4.7,0.11)
    178 156 176 149
    B 1.00 0.94 0.95
    (0.0,0.00) (4.6,0.11) (3.6,0.10)
    343 320 276
    C 1.00 0.96
    (0.0,0.00) (4.4,0.11)
    984 313
    D 1.00
    (0.0, 0.00)
    333
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    
    
    J
    
    
    K
    
    
    L
    
    
    M
    
    
    N
    
    
    0
    E
    0.97
    (3.9, 0.09)
    154
    0.97
    (3.3, 0.08)
    300
    0.92
    (5.7,0.11)
    325
    0.94
    (3.8,0.10)
    286
    1.00
    (0.0, 0.00)
    351
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    F
    0.95
    (5.7,0.13)
    154
    0.95
    (5.2,0.13)
    296
    0.91
    (4.8,0.11)
    318
    0.93
    (4.2,0.12)
    280
    0.95
    (5.0,0.11)
    306
    1.00
    (0.0, 0.00)
    345
    
    
    
    
    
    
    
    
    
    
    
    LEGEND
    R
    (P90, COD)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    G
    0.97
    (3.9, 0.09)
    151
    0.97
    (2.7, 0.07)
    296
    0.90
    (6.0,0.12)
    324
    0.94
    (3.8,0.10)
    283
    0.98
    (2.4, 0.06)
    304
    0.95
    (5.1,0.12)
    301
    1.00
    (0.0, 0.00)
    350
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    H
    0.94
    (4.6,0.12)
    156
    0.95
    (4.3,0.11)
    289
    0.94
    (4.3,0.11)
    312
    0.95
    (4.1,0.13)
    270
    0.95
    (4.5,0.11)
    292
    0.95
    (4.5,0.12)
    294
    0.95
    (4.9,0.12)
    284
    1.00
    (0.0, 0.00)
    335
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    0.96
    (4.2,0.11)
    164
    0.96
    (3.4, 0.09)
    312
    0.92
    (5.5,0.11)
    336
    0.94
    (3.3,0.10)
    299
    0.98
    (2.6, 0.07)
    320
    0.96
    (4.5,0.10)
    322
    0.97
    (3.0, 0.07)
    315
    0.95
    (4.3,0.11)
    311
    1.00
    (0.0, 0.00)
    361
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    J
    0.91
    (6.8,0.16)
    163
    0.93
    (6.3,0.16)
    315
    0.90
    (8.8,0.18)
    332
    0.93
    (6.2,0.15)
    296
    0.92
    (5.8,0.16)
    321
    0.89
    (8.5, 0.20)
    323
    0.90
    (6.3,0.15)
    318
    0.91
    (7.4,0.19)
    309
    0.90
    (6.7,0.17)
    341
    1.00
    (0.0, 0.00)
    356
    
    
    
    
    
    
    
    
    
    
    
    
    
    K
    0.95
    (5.8,0.14)
    166
    0.93
    (6.5,0.15)
    306
    0.91
    (7.2,0.17)
    337
    0.93
    (5.2,0.14)
    289
    0.92
    (5.7,0.15)
    313
    0.91
    (7.9,0.19)
    311
    0.91
    (5.8,0.14)
    309
    0.92
    (6.4,0.18)
    302
    0.92
    (5.9,0.16)
    328
    0.92
    (4.7,0.13)
    330
    1.00
    (0.0, 0.00)
    361
    
    
    
    
    
    
    
    
    
    
    L
    0.95
    (4.6,0.12)
    141
    0.95
    (4.0,0.10)
    288
    0.92
    (4.5,0.12)
    311
    0.92
    (3.6,0.10)
    273
    0.95
    (4.4,0.10)
    286
    0.94
    (5.7,0.12)
    285
    0.94
    (4.7,0.10)
    287
    0.94
    (4.4,0.13)
    275
    0.96
    (3.9,0.10)
    304
    0.90
    (7.0,0.17)
    304
    0.93
    (5.9,0.15)
    292
    1.00
    (0.0, 0.00)
    331
    
    
    
    
    
    
    
    M
    0.91
    (5.7,0.15)
    165
    0.92
    (5.1,0.15)
    157
    0.88
    (7.5,0.16)
    178
    0.89
    (5.3,0.14)
    151
    0.95
    (4.8,0.11)
    159
    0.94
    (7.0,0.15)
    161
    0.95
    (4.2,0.11)
    154
    0.93
    (6.4,0.16)
    164
    0.96
    (4.6,0.12)
    173
    0.91
    (5.7,0.14)
    171
    0.94
    (5.2,0.13)
    173
    0.94
    (6.4,0.13)
    147
    1.00
    (0.0, 0.00)
    179
    
    
    
    
    N
    0.92
    (6.6,0.15)
    152
    0.93
    (5.8, 0.14)
    152
    0.92
    (7.9,0.16)
    175
    0.96
    (5.1,0.13)
    146
    0.94
    (5.0,0.11)
    154
    0.94
    (7.9,0.17)
    157
    0.95
    (5.0,0.12)
    149
    0.94
    (7.1,0.16)
    157
    0.95
    (5.3,0.13)
    169
    0.94
    (4.4,0.12)
    165
    0.96
    (4.0,0.10)
    166
    0.95
    (5.9,0.13)
    142
    0.97
    (3.9, 0.09)
    160
    1.00
    (0.0, 0.00)
    176
    
    0
    0.89
    (6.0,0.16)
    156
    0.90
    (5.2,0.15)
    150
    0.86
    (7.5,0.17)
    173
    0.88
    (4.5,0.15)
    145
    0.92
    (4.6,0.13)
    152
    0.94
    (7.9,0.16)
    154
    0.95
    (4.4,0.12)
    148
    0.91
    (5.9,0.17)
    156
    0.93
    (4.6,0.14)
    166
    0.89
    (5.4,0.16)
    164
    0.92
    (4.9,0.15)
    167
    0.92
    (6.0,0.14)
    142
    0.95
    (2.7,0.11)
    165
    0.95
    (3.8,0.11)
    152
    1.00
    (0.0, 0.00)
    174
    December 2009                                  A-111
    

    -------
    p
    A 0.90
    (8.0,0.19)
    166
    B 0.90
    (8.0, 0.20)
    159
    C 0.89
    (10.2,0.22)
    180
    D 0.90
    (7.6,0.19)
    153
    E 0.91
    (8.3,0.18)
    160
    F 0.91
    (10.5,0.23)
    163
    G 0.91
    (7.9,0.19)
    156
    H 0.91
    (9.3, 0.23)
    165
    I 0.91
    (8.2,0.21)
    175
    J 0.92
    (5.6,0.14)
    173
    K 0.94
    (5.2,0.12)
    176
    L 0.90
    (9.3, 0.20)
    151
    M 0.92
    (6.2,0.16)
    175
    N 0.92
    (5.4,0.13)
    162
    0 0.88
    (7.5,0.18)
    166
    P 1.00
    (0.0, 0.00)
    181
    Q
    
    
    R
    
    
    S
    
    
    T
    
    
    U
    
    
    V
    
    
    W
    
    
    X
    
    
    Y
    
    
    Z
    
    
    AA
    
    
    AB
    
    
    AC
    
    
    AD
    
    
    AE
    Q
    0.89
    (7.5,0.19)
    151
    0.90
    (6.7,0.17)
    290
    0.91
    (8.3,0.19)
    324
    0.94
    (6.5,0.16)
    278
    0.92
    (5.6,0.16)
    294
    0.92
    (8.6, 0.20)
    295
    0.91
    (5.9,0.16)
    292
    0.93
    (7.1,0.20)
    284
    0.92
    (6.1,0.17)
    314
    0.91
    (5.1,0.14)
    313
    0.93
    (4.2,0.12)
    298
    0.92
    (6.7,0.17)
    285
    0.95
    (4.5,0.14)
    157
    0.98
    (2.8, 0.08)
    151
    0.92
    (4.9,0.15)
    152
    0.92
    (5.2,0.13)
    159
    1.00
    (0.0, 0.00)
    347
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    R
    0.91
    (5.6,0.16)
    157
    0.91
    (5.5,0.16)
    153
    0.86
    (7.1,0.17)
    172
    0.89
    (5.5,0.14)
    147
    0.94
    (4.9,0.12)
    155
    0.92
    (8.5,0.17)
    159
    0.95
    (4.1,0.12)
    154
    0.92
    (6.6,0.17)
    158
    0.95
    (4.7,0.12)
    168
    0.90
    (6.2,0.16)
    167
    0.93
    (6.1,0.16)
    169
    0.93
    (6.7,0.14)
    144
    0.96
    (3.4, 0.09)
    165
    0.94
    (4.1,0.12)
    153
    0.93
    (3.8,0.13)
    157
    0.90
    (7.1,0.17)
    166
    0.92
    (5.4,0.16)
    154
    1.00
    (0.0, 0.00)
    175
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    LEC
    (P90
    
    
    
    
    
    
    
    
    
    s
    0.83
    (8.0, 0.24)
    145
    0.83
    (8.0, 0.24)
    143
    0.78
    (10.4,0.25)
    164
    0.80
    (8.6, 0.22)
    135
    0.87
    (7.1,0.20)
    142
    0.87
    (10.0,0.25)
    144
    0.88
    (7.1,0.21)
    140
    0.82
    (9.6, 0.26)
    145
    0.87
    (7.7, 0.22)
    154
    0.85
    (6.7,0.21)
    153
    0.86
    (7.2, 0.20)
    155
    0.86
    (8.9,0.21)
    132
    0.88
    (6.3,0.19)
    152
    0.89
    (5.8,0.17)
    140
    0.86
    (6.5, 0.20)
    145
    0.84
    (7.2, 0.20)
    152
    0.85
    (7.2,0.19)
    139
    0.91
    (5.8,0.18)
    143
    1.00
    (0.0, 0.00)
    164
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    SEND
    R
    , COD)
    N
    
    
    
    
    
    
    
    
    
    T
    0.96
    (4.4,0.11)
    154
    0.95
    (3.9,0.10)
    292
    0.90
    (6.9,0.13)
    309
    0.92
    (5.0,0.12)
    280
    0.94
    (4.1,0.10)
    300
    0.90
    (6.9,0.14)
    302
    0.94
    (3.9,0.10)
    293
    0.92
    (5.7,0.13)
    287
    0.93
    (4.2,0.10)
    318
    0.89
    (6.1,0.17)
    319
    0.91
    (5.1,0.16)
    310
    0.93
    (5.5,0.12)
    285
    0.91
    (5.9,0.14)
    162
    0.92
    (6.2,0.13)
    156
    0.89
    (5.9,0.15)
    155
    0.88
    (8.5, 0.20)
    164
    0.88
    (6.1,0.18)
    290
    0.93
    (5.1,0.13)
    157
    0.83
    (8.5, 0.22)
    144
    1.00
    (0.0, 0.00)
    330
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    U
    0.83
    (7.2,0.16)
    162
    0.81
    (6.7,0.15)
    310
    0.76
    (8.5,0.18)
    327
    0.74
    (7.8,0.19)
    294
    0.77
    (7.5,0.17)
    320
    0.74
    (9.2,0.19)
    320
    0.76
    (7.5,0.17)
    315
    0.78
    (7.5,0.17)
    307
    0.78
    (7.1,0.17)
    338
    0.73
    (8.6, 0.22)
    341
    0.78
    (8.0,0.21)
    327
    0.75
    (8.2,0.19)
    301
    0.74
    (9.0, 0.22)
    171
    0.81
    (7.9, 0.20)
    165
    0.75
    (8.8, 0.22)
    166
    0.73
    (12.0,0.26)
    174
    0.71
    (9.3, 0.24)
    309
    0.76
    (8.6, 0.22)
    167
    0.66
    (11.3,0.28)
    153
    0.81
    (5.9,0.15)
    318
    1.00
    (0.0, 0.00)
    351
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    V
    0.93
    (5.9,0.13)
    159
    0.94
    (5.2,0.11)
    300
    0.89
    (6.4,0.13)
    315
    0.91
    (5.9,0.13)
    283
    0.94
    (5.6,0.12)
    310
    0.93
    (5.4,0.11)
    308
    0.95
    (4.7,0.10)
    303
    0.92
    (6.1,0.13)
    297
    0.94
    (5.0,0.10)
    327
    0.89
    (8.7, 0.20)
    329
    0.89
    (8.4,0.19)
    319
    0.92
    (6.2,0.13)
    290
    0.90
    (8.0,0.17)
    166
    0.91
    (8.3,0.17)
    160
    0.89
    (7.6,0.17)
    161
    0.87
    (10.9,0.24)
    168
    0.89
    (9.1,0.21)
    296
    0.90
    (7.5,0.17)
    161
    0.81
    (11.6,0.26)
    148
    0.93
    (6.2,0.12)
    307
    0.77
    (7.6,0.17)
    327
    1.00
    (0.0, 0.00)
    339
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    W
    0.95
    (4.7,0.12)
    149
    0.95
    (5.0,0.11)
    289
    0.90
    (7.7,0.15)
    305
    0.94
    (5.4,0.13)
    273
    0.96
    (4.3,0.10)
    299
    0.92
    (8.2,0.16)
    297
    0.97
    (3.7, 0.09)
    293
    0.91
    (6.8,0.15)
    288
    0.95
    (4.6,0.11)
    316
    0.89
    (6.0,0.16)
    317
    0.91
    (5.2,0.15)
    304
    0.93
    (5.7,0.13)
    282
    0.94
    (4.7,0.12)
    159
    0.92
    (4.9,0.12)
    157
    0.92
    (5.1,0.13)
    154
    0.89
    (6.7,0.18)
    160
    0.90
    (5.5,0.16)
    289
    0.94
    (4.4,0.11)
    153
    0.86
    (6.7, 0.20)
    143
    0.95
    (3.4,0.10)
    297
    0.79
    (6.6,0.17)
    319
    0.96
    (5.9,0.11)
    306
    1.00
    (0.0, 0.00)
    328
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    X
    0.96
    (4.4,0.10)
    156
    0.96
    (4.0,0.10)
    292
    0.90
    (7.1,0.14)
    311
    0.93
    (5.4,0.13)
    282
    0.95
    (4.4,0.11)
    303
    0.92
    (7.2,0.15)
    305
    0.96
    (3.6, 0.09)
    296
    0.92
    (5.9,0.15)
    292
    0.94
    (4.8,0.11)
    322
    0.89
    (6.3,0.16)
    327
    0.90
    (5.5,0.15)
    313
    0.93
    (5.8,0.13)
    286
    0.92
    (5.2,0.14)
    164
    0.91
    (5.6,0.14)
    158
    0.90
    (5.8,0.15)
    158
    0.89
    (7.4,0.18)
    166
    0.88
    (6.5,0.16)
    294
    0.93
    (5.0,0.13)
    160
    0.83
    (8.0,0.21)
    146
    0.97
    (3.2, 0.09)
    302
    0.81
    (6.0,0.15)
    322
    0.97
    (4.8,0.10)
    314
    0.98
    (2.8, 0.06)
    299
    1.00
    (0.0, 0.00)
    334
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Y
    0.95
    (4.5,0.12)
    160
    0.96
    (4.2,0.11)
    300
    0.90
    (7.9,0.15)
    317
    0.93
    (5.8,0.13)
    284
    0.96
    (3.9, 0.09)
    310
    0.92
    (7.6,0.15)
    311
    0.97
    (3.5, 0.08)
    303
    0.92
    (6.7,0.14)
    299
    0.95
    (4.7,0.10)
    328
    0.89
    (6.2,0.16)
    329
    0.91
    (5.2,0.15)
    319
    0.92
    (6.2,0.13)
    293
    0.93
    (5.0,0.13)
    168
    0.93
    (4.6,0.13)
    162
    0.91
    (5.5,0.14)
    161
    0.89
    (6.9,0.18)
    169
    0.90
    (5.5,0.16)
    302
    0.94
    (4.0,0.12)
    161
    0.87
    (7.2,0.19)
    148
    0.96
    (2.9, 0.08)
    305
    0.81
    (6.3,0.16)
    326
    0.95
    (5.8,0.12)
    316
    0.98
    (2.5, 0.07)
    306
    0.98
    (2.3, 0.07)
    311
    1.00
    (0.0, 0.00)
    340
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Z
    0.98
    (3.4,0.10)
    160
    0.98
    (2.9, 0.09)
    309
    0.93
    (6.7,0.15)
    323
    0.95
    (4.8,0.13)
    292
    0.96
    (3.9,0.11)
    317
    0.93
    (6.3,0.16)
    316
    0.96
    (3.4,0.11)
    312
    0.93
    (5.9,0.15)
    303
    0.95
    (4.2,0.13)
    335
    0.91
    (5.9,0.16)
    337
    0.92
    (5.4, 0.14)
    325
    0.95
    (5.0,0.13)
    299
    0.92
    (5.8,0.16)
    169
    0.93
    (4.9,0.15)
    165
    0.90
    (5.6,0.16)
    162
    0.90
    (7.6,0.19)
    171
    0.90
    (6.3,0.16)
    306
    0.91
    (5.8,0.17)
    164
    0.83
    (7.3, 0.22)
    151
    0.97
    (3.2,0.12)
    315
    0.81
    (6.4,0.17)
    336
    0.95
    (5.7, 0.14)
    325
    0.96
    (3.6,0.11)
    312
    0.97
    (3.3,0.10)
    318
    0.97
    (3.6,0.11)
    322
    1.00
    (0.0, 0.00)
    347
    
    
    
    
    
    
    
    
    
    
    
    
    
    AA
    0.94
    (5.8,0.17)
    154
    0.94
    (5.9,0.17)
    288
    0.87
    (8.6, 0.20)
    491
    0.92
    (6.4,0.17)
    274
    0.93
    (5.8,0.17)
    292
    0.91
    (8.5, 0.22)
    292
    0.92
    (5.7,0.17)
    288
    0.90
    (7.7, 0.22)
    281
    0.92
    (6.5,0.18)
    306
    0.89
    (5.6,0.16)
    307
    0.92
    (5.2,0.15)
    301
    0.92
    (7.2,0.17)
    277
    0.91
    (6.4,0.17)
    158
    0.91
    (5.4,0.15)
    153
    0.89
    (6.1,0.17)
    151
    0.89
    (6.1,0.16)
    158
    0.89
    (5.3,0.16)
    292
    0.92
    (6.2,0.17)
    153
    0.84
    (6.1,0.21)
    141
    0.92
    (5.2,0.17)
    284
    0.78
    (8.1,0.22)
    305
    0.93
    (7.7, 0.20)
    292
    0.95
    (4.5,0.15)
    281
    0.95
    (4.6,0.14)
    286
    0.95
    (4.7,0.16)
    296
    0.95
    (4.6,0.15)
    305
    1.00
    (0.0, 0.00)
    532
    
    
    
    
    
    
    
    
    
    
    AB
    0.93
    (6.8,0.17)
    159
    0.92
    (6.8,0.17)
    308
    0.88
    (8.9, 0.20)
    323
    0.90
    (6.9,0.18)
    291
    0.91
    (6.9,0.17)
    314
    0.90
    (9.4,0.21)
    317
    0.92
    (6.8,0.16)
    311
    0.89
    (8.1,0.22)
    301
    0.91
    (6.8,0.18)
    334
    0.88
    (5.8,0.16)
    335
    0.91
    (4.9,0.15)
    325
    0.92
    (7.6,0.17)
    299
    0.91
    (5.5,0.15)
    168
    0.91
    (4.9,0.14)
    162
    0.90
    (5.7,0.16)
    161
    0.90
    (5.7,0.15)
    170
    0.88
    (5.3,0.16)
    303
    0.92
    (5.6,0.16)
    164
    0.84
    (7.4, 0.20)
    151
    0.91
    (5.5,0.16)
    312
    0.76
    (8.4, 0.22)
    334
    0.91
    (8.6, 0.20)
    323
    0.93
    (4.8,0.15)
    310
    0.93
    (4.9,0.14)
    319
    0.93
    (5.0,0.15)
    322
    0.93
    (5.3,0.15)
    331
    0.98
    (2.4, 0.07)
    305
    1.00
    (0.0, 0.00)
    346
    
    
    
    
    
    
    
    AC
    0.95
    (6.0,0.16)
    158
    0.93
    (6.5,0.18)
    299
    0.88
    (9.6,0.21)
    313
    0.90
    (7.0,0.19)
    287
    0.90
    (6.8,0.18)
    304
    0.87
    (9.1,0.23)
    306
    0.90
    (6.8,0.18)
    300
    0.88
    (8.3, 0.22)
    293
    0.89
    (7.4,0.19)
    323
    0.87
    (6.3,0.17)
    327
    0.90
    (5.3,0.16)
    315
    0.90
    (7.4,0.18)
    286
    0.88
    (6.9,0.19)
    165
    0.88
    (6.5,0.17)
    158
    0.87
    (7.0,0.19)
    159
    0.89
    (6.3,0.17)
    167
    0.86
    (6.3,0.18)
    293
    0.88
    (7.1,0.19)
    160
    0.81
    (7.8, 0.23)
    149
    0.92
    (5.4,0.18)
    311
    0.79
    (7.2,0.21)
    324
    0.90
    (8.3,0.21)
    314
    0.92
    (5.4,0.16)
    306
    0.94
    (4.9,0.15)
    305
    0.92
    (5.3,0.17)
    311
    0.94
    (4.9,0.15)
    321
    0.97
    (2.9, 0.08)
    287
    0.96
    (3.1,0.09)
    317
    1.00
    (0.0, 0.00)
    336
    
    
    
    
    AD
    0.94
    (5.4,0.15)
    159
    0.87
    (5.3,0.16)
    305
    0.84
    (8.7,0.18)
    323
    0.85
    (6.2,0.17)
    290
    0.86
    (6.3,0.16)
    313
    0.83
    (8.3, 0.20)
    317
    0.87
    (5.9,0.15)
    308
    0.83
    (8.1,0.20)
    301
    0.85
    (6.6,0.17)
    334
    0.82
    (6.3,0.17)
    336
    0.85
    (5.3,0.16)
    323
    0.85
    (7.3,0.16)
    294
    0.89
    (6.2,0.17)
    168
    0.89
    (5.4,0.16)
    161
    0.87
    (6.2,0.17)
    162
    0.89
    (6.4,0.17)
    170
    0.82
    (5.9,0.17)
    303
    0.89
    (6.4,0.17)
    163
    0.82
    (7.1,0.22)
    148
    0.87
    (4.9,0.15)
    313
    0.74
    (7.0,0.19)
    333
    0.88
    (6.9,0.17)
    321
    0.89
    (3.9,0.13)
    311
    0.91
    (3.6,0.11)
    316
    0.89
    (4.4,0.14)
    321
    0.89
    (4.1,0.14)
    328
    0.89
    (3.2,0.11)
    300
    0.89
    (3.7,0.11)
    328
    0.91
    (2.8,0.10)
    320
    1.00
    (0.0, 0.00)
    346
    
    AE
    0.88
    (7.1,0.17)
    162
    0.87
    (7.2,0.17)
    311
    0.79
    (8.5, 0.20)
    333
    0.87
    (6.9,0.17)
    297
    0.87
    (7.3,0.17)
    318
    0.84
    (9.3,0.21)
    322
    0.85
    (7.5,0.17)
    314
    0.88
    (7.6, 0.20)
    307
    0.86
    (7.0,0.18)
    339
    0.87
    (6.4,0.15)
    340
    0.91
    (5.1,0.13)
    328
    0.89
    (7.1,0.17)
    301
    0.89
    (6.9,0.17)
    171
    0.90
    (6.0,0.14)
    165
    0.87
    (7.0,0.18)
    166
    0.92
    (5.7,0.13)
    173
    0.91
    (5.5,0.14)
    310
    0.89
    (7.1,0.17)
    166
    0.80
    (9.0, 0.22)
    153
    0.85
    (6.6,0.18)
    319
    0.69
    (10.0,0.23)
    338
    0.83
    (9.3, 0.22)
    325
    0.85
    (6.9,0.17)
    316
    0.85
    (6.8,0.17)
    321
    0.85
    (6.7,0.18)
    326
    0.86
    (6.8,0.17)
    335
    0.88
    (5.9,0.17)
    304
    0.86
    (6.5,0.17)
    333
    0.85
    (6.7,0.17)
    322
    0.79
    (7.2,0.18)
    332
    1.00
    December 2009                                       A-112
    

    -------
         P      QR     S     T      U      VWXYZAAABACADAE
    
        	(0.0, 0.00)
    
                                                                                                    355
        0.8
        0.6
                   » «  «   »•
                                                    »*     *
      o
      O
        0.4
        0.2
                    10       20       30
                                              40       50       60
    
                                            Distance Between Samplers (km)
                                                                         70        80        90       100
    Figure A -48.   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                   Chicago, IL
    December 2009
                                                   A-113
    

    -------
                     Denver Combined Statistical Area
            A
          01
                                          0  10 20   40
                    |	| Denver CSA
                      •   PMz.s Monitors
                    	 Interstate Highways
                       — Major Highways
    
                   60    80   100
                  H^^^H^Z^ZI Kilometers
    Figure A-49.  PM2.s monitor distribution and major highways, Denver, CO.
    December 2009
    A-114
    

    -------
    AQS Site ID A
    Site A 08-001-0006
    SiteB 08-005-0005 "
    SiteC 08-013-0003 Obs 369
    SiteD 08-013-0012 SD
    SiteE 08-031-0002 4Q .
    SiteF 08-031-0023
    SiteG 08-123-0006
    SiteH 08-123-0008
    " 30 -
    Ol
    c
    o
    2 20-
    c
    u
    c
    o
    10 -
    1=winter
    2=spring
    3=summer "
    5.9
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    B
    363
    
    
    
    
    
    
    
    
    
    
    
    
    5.3
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    "
    
    
    C
    8.2
    361
    
    
    
    
    
    
    
    
    
    
    
    
    4.7
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    •I
    f
    
    D
    7.0
    354
    
    
    
    
    
    
    
    
    
    
    
    
    3.9
    
    
    
    
    
    
    
    
    
    
    
    
    
    II
    1
    
    E
    F
    9.2 9.7
    1046 1006
    
    
    
    
    
    
    
    
    
    
    
    
    5.5
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    5.6
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    G
    H
    8.3 9.1
    359 334
    
    
    
    
    
    
    
    
    
    
    
    
    5.3
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    5.8
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                         4=fall      1234  1234  1234  1234  1234  1234  1234  1234
    Figure A-50.   Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                  for Denver, CO.
    December 2009
    A-115
    

    -------
    Table A-24.
    A
    A 1.00
    (0.0, 0.00)
    369
    B
    
    
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
    Denver, CO.
    B C D E
    0.74 0.84 0.68 0.86
    (6.0,0.21) (5.4,0.17) (7.9,0.26) (4.1,0.14)
    353 347 332 362
    1.00 0.58 0.76 0.92
    (0.0,0.00) (5.7,0.19) (3.9,0.17) (3.2,0.13)
    363 344 328 356
    1.00 0.74 0.71
    (0.0,0.00) (4.4,0.19) (4.5,0.17)
    361 326 354
    1.00 0.82
    (0.0,0.00) (5.6,0.21)
    354 347
    1.00
    LEGEND (0.0, 0.00)
    R 1046
    (P90, COD)
    N
    
    
    
    
    
    F
    0.91
    (3.0,0.11)
    339
    0.84
    (4.4,0.17)
    336
    0.75
    (5.4,0.18)
    336
    0.77
    (6.0, 0.24)
    332
    0.94
    (2.3, 0.09)
    969
    1.00
    (0.0, 0.00)
    1006
    
    
    
    
    G
    0.76
    (5.9,0.19)
    341
    0.50
    (7.8, 0.23)
    337
    0.83
    (3.5,0.14)
    333
    0.54
    (7.2, 0.24)
    318
    0.64
    (7.1,0.21)
    353
    0.68
    (6.6,0.21)
    333
    1.00
    (0.0, 0.00)
    359
    
    H
    0.83
    (4.6,0.14)
    325
    0.49
    (6.6,0.21)
    323
    0.88
    (3.7,0.13)
    320
    0.57
    (6.4, 0.24)
    305
    0.60
    (5.6,0.18)
    330
    0.69
    (5.9,0.17)
    317
    0.88
    (3.4,0.13)
    313
    1.00
    (0.0, 0.00)
    334
    December 2009                                       A-116
    

    -------
        0.8
        0.6
      o
      o
        0.4
        0.2
                   10        20       30       40       50       60
    
    
                                           Distance Between Samplers (km)
                                                                       70       80       90       100
    Figure A-51.   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                   Denver, CO.
    December 2009
    A-117
    

    -------
                       Detroit Combined Statistical Area
            A
           01
                         Detroit CSA
                      •  PMz.s Monitors
                      	 Interstate Highways
                        — Major Highways
                              0   10  20      40       60       80
                                100
                               —i Kilometers
    Figure A-52.   PM2.s monitor distribution and major highways, Detroit, Ml.
    December 2009
    A-118
    

    -------
                           Site A
                           SiteB
                           SiteC
                           SiteD
                           SiteE
                           SiteF
                           SiteG
    AQS Site ID
    26-049-0021
    26-099-0009
    26-115-0005
    26-125-0001
    26-147-0005
    26-161-0008
    26-163-0001
    ) A B C D E F G
    1 Mean 11.6 12.9 13.8 13.9 13.5 13.7 14.0
    Q
    Obs 356 306 342 308 303 350 1049
    1 SD 7.5 9.4 9.1 9.5 9.9 8.9 8.9
    5 50 -
    8
    ^
    40 -
    IE
    Dl
    3 30 -
    c
    
    -------
    Table A-25.   Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
                 Detroit, Ml.
    A
    A 1.00
    (0.0, 0.00)
    356
    B
    
    
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    
    
    J
    
    
    K
    
    
    L
    
    
    M
    B C D E F
    0.91 0.86 0.91 0.89 0.90
    (5.9,0.17) (7.8,0.19) (6.7,0.17) (7.6,0.18) (5.9,0.18)
    299 333 301 296 341
    1.00 0.90 0.94 0.92 0.92
    (0.0,0.00) (6.8,0.17) (5.3,0.14) (5.9,0.16) (5.8,0.17)
    306 286 296 290 294
    1.00 0.90 0.87 0.91
    (0.0,0.00) (7.0,0.16) (8.8,0.20) (5.5,0.15)
    342 289 284 326
    1.00 0.93 0.94
    (0.0,0.00) (6.3,0.15) (4.5,0.14)
    308 292 296
    1.00 0.90
    (0.0,0.00) (7.5,0.18)
    303 291
    1.00
    (0.0, 0.00)
    350
    
    
    
    
    
    
    LEGEND
    R
    (P90, COD)
    N
    
    
    
    
    
    
    
    
    
    G
    0.89
    (8.1,0.20)
    349
    0.93
    (6.2,0.18)
    300
    0.93
    (5.9,0.14)
    335
    0.96
    (4.3,0.13)
    303
    0.90
    (7.3, 0.20)
    297
    0.95
    (4.5,0.13)
    343
    1.00
    (0.0, 0.00)
    1049
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    H
    0.88
    (8.3, 0.22)
    334
    0.90
    (7.5,0.21)
    288
    0.90
    (7.2,0.17)
    320
    0.92
    (5.8,0.16)
    291
    0.89
    (8.2, 0.22)
    286
    0.90
    (6.2,0.17)
    326
    0.94
    (5.1,0.14)
    336
    1.00
    (0.0, 0.00)
    342
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    0.89
    (8.0,0.19)
    284
    0.92
    (5.8,0.18)
    277
    0.91
    (6.3,0.16)
    273
    0.94
    (4.5,0.12)
    281
    0.90
    (7.0,0.19)
    276
    0.92
    (5.7,0.15)
    280
    0.95
    (4.9,0.12)
    549
    0.93
    (4.8,0.15)
    273
    1.00
    (0.0, 0.00)
    572
    
    
    
    
    
    
    
    
    
    
    J
    0.91
    (7.3,0.17)
    301
    0.91
    (4.9,0.16)
    297
    0.90
    (6.2,0.14)
    286
    0.94
    (3.8,0.11)
    297
    0.90
    (6.4,0.18)
    292
    0.92
    (5.2,0.14)
    297
    0.92
    (4.5,0.14)
    302
    0.91
    (5.4,0.15)
    290
    0.92
    (4.4,0.13)
    279
    1.00
    (0.0, 0.00)
    308
    
    
    
    
    
    
    
    K
    0.92
    (5.5,0.16)
    293
    0.92
    (5.4,0.17)
    286
    0.89
    (6.2,0.16)
    279
    0.94
    (3.6,0.13)
    291
    0.90
    (6.9,0.18)
    284
    0.95
    (3.9,0.12)
    288
    0.93
    (5.6,0.16)
    295
    0.89
    (6.9,0.18)
    288
    0.90
    (6.1,0.14)
    271
    0.91
    (5.3,0.15)
    288
    1.00
    (0.0, 0.00)
    301
    
    
    
    
    L
    0.87
    (11.0,0.26)
    336
    0.89
    (10.2,0.24)
    292
    0.87
    (10.4,0.20)
    321
    0.91
    (8.2,0.18)
    290
    0.87
    (10.7,0.25)
    288
    0.89
    (9.8,0.21)
    329
    0.90
    (8.2,0.18)
    337
    0.91
    (7.6,0.16)
    321
    0.92
    (7.9,0.18)
    274
    0.90
    (8.1,0.17)
    291
    0.88
    (9.5,0.21)
    281
    1.00
    (0.0, 0.00)
    344
    
    M
    0.88
    (7.8,
    333
    0.91
    (6.1,
    288
    0.93
    (4.9,
    319
    0.92
    (6.2,
    290
    0.87
    (7.7,
    288
    0.93
    (5.7,
    326
    0.95
    (4.7,
    335
    0.91
    (6.1,
    319
    0.93
    (5.8,
    274
    0.91
    (5.6,
    291
    0.91
    (6.3,
    283
    0.91
    (8.5,
    322
    1.00
    
    0.21)
    
    
    0.19)
    
    
    0.13)
    
    
    0.15)
    
    
    0.21)
    
    
    0.15)
    
    
    0.12)
    
    
    0.15)
    
    
    0.14)
    
    
    0.13)
    
    
    0.16)
    
    
    0.17)
    
    
    (0.0, 0.00)
    342
    December 2009                                  A-120
    

    -------
                                                                    **    •
        0.8
        0.6
      o
      13
      o
      O
        0.4
        0.2
                   10       20        30       40       50       60        70
    
                                            Distance Between Samplers (km)
                                                                                80       90       100
    Figure A-54.   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                   Detroit, Ml.
    December 2009
    A-121
    

    -------
                     Houston  Combined Statistical Area
            A
          01
                            Houston CSA
                         •  PM2.5 Monitors
                         	 Interstate Highways
                           — Major Highways
                                          0 10 20   40   60   80
                            100
                           —i Kilometers
    Figure A-55.  PM2.s monitor distribution and major highways, Houston, TX.
    December 2009
    A-122
    

    -------
                                  AQS Site ID
                           Site A   48-201-0058
                           SiteB   48-201-1035
    Mean
     Obs
      SD
     A
    11.3
    326
    5.5
     B
    15.8
    1016
    6.2
    40 -
    30 -
    IE
    Ol
    IL
    0 20 -
    ro
    concenti
    O
    1=winter
    2=spring
    3=summer 0 -
    4=fall
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    1234 1234
    Figure A-56.   Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                   for Houston, TX.
    Table A-26.   Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
                 Houston, TX.
    A B
    A
    1.00 0.66
    (0.0,0.00) (10.0,0.24)
    326 310
    B
    1.00
    (0.0,0.00)
    1016
    LEGEND
    R
    (P90, COD)
    N
    December 2009
      A-123
    

    -------
        0.8
        0.6
      HI
    
      5
      o
        0.4
        0.2
                   10       20       30       40       50       60
    
    
                                           Distance Between Samplers (km)
                                                                       70       80       90       100
    Figure A-57.   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                   Houston, TX.
    December 2009
    A-124
    

    -------
                 Los Angeles Core  Based Statistical Area
          01
             r
                             Los Angeles CBSA
                         •   PM2.5 Monitors
                         	 Interstate Highways
                           — Major Highways
                                0  10  20      40       60      80
                                100
                               —i Kilometers
    Figure A-58.  PM2.s monitor distribution and major highways, Los Angeles, CA.
    December 2009
    A-125
    

    -------
               SteA
               SteB
               SiteC
               SteD
               SiteE
               SiteF
               SiteG
               SiteH
               She I
               SiteJ
               SteK
    AQSSKelD
    06-037-0002
    06-037-1002
    06-037-1103
    06-037-1201
    06-037-1301
    06-037-2005
    06-037^1002
    06-037-1O04
    06-037-9033
    06-059-O007
    06-059-2022
                       1=winter
                       2=spring
                       3=summer
                       4=fall
    ABCDEFGH1JK
    Mean 16.1 17.0 16.7 13.3 16.7 14.3 4.7 4.2 8.2 14.4 10.9
    Obs 862 308 1004 291 327 334 946 990 221 999 318
    SD 10.8 10.2 9.8 7.5 9.3 8.9 8.4 7.7 3.8 8.5 6.4
    60 -
    50 -
    IE
    c
    o
    TO 30 -
    c=
    QJ
    020-
    1 0-
    o -
    
    
    
    
    
    
    
    1 | 1 1
    
    
    
    
    
    
    1
    1
    
    
    
    
    
    
    
    II
    
    
    
    
    
    
    I
    1
    
    
    
    
    
    
    
    '!"
    
    
    
    
    
    
    
    
    
    
    
    
    i
    I
    
    
    
    
    
    
    
    1'
                                      1234  1234 1234  1234 1234  1234  1234 1234  1234  1234  1234
    Figure A-59.    Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                      for Los Angeles, CA.
    December 2009
                                          A-126
    

    -------
    Table A-27.   Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
                 Los Angeles, CA.
    A B C D E
    A 1.00 0.86 0.87 0.81 0.80
    (0.0,0.00) (9.0,0.18) (7.7,0.16) (9.0,0.19) (9.7,0.21)
    862 252 803 238 262
    B 1.00 0.92 0.87 0.83
    (0.0,0.00) (5.5,0.11) (9.1,0.19) (9.0,0.15)
    308 293 250 278
    C 1.00 0.80 0.89
    (0.0,0.00) (9.6,0.20) (5.8,0.11)
    1004 274 315
    D 1.00 0.69
    (0.0,0.00) (10.9,0.23)
    291 263
    E 1.00
    (0.0, 0.00)
    327
    F
    
    
    G
    
    
    LEGEND
    Pearcon R
    (P90 COD)
    
    
    H
    
    
    I
    
    
    J
    
    
    K
    F G
    0.88 0.68
    (5.8,0.14) (11.5,0.22)
    269 761
    0.88 0.77
    (7.6,0.15) (9.8,0.17)
    279 268
    0.92 0.84
    (6.4,0.13) (9.0,0.15)
    319 880
    0.77 0.63
    (7.4,0.18) (11.3,0.22)
    263 256
    0.79 0.95
    (9.1,0.19) (5.9,0.11)
    301 289
    1.00 0.70
    (0.0,0.00) (10.5,0.18)
    334 290
    1.00
    (0.0, 0.00)
    946
    
    
    
    
    
    
    
    
    
    
    H
    0.64
    (12.4,0.23)
    793
    0.73
    (11.6,0.18)
    282
    0.79
    (10.0,0.17)
    913
    0.60
    (11.1,0.22)
    268
    0.92
    (7.6,0.13)
    301
    0.70
    (9.2,0.19)
    302
    0.96
    (4.0, 0.09)
    859
    1.00
    (0.0, 0.00)
    990
    
    
    
    
    
    
    
    1
    0.30
    (18.0,0.36)
    179
    0.31
    (24.1,0.38)
    177
    0.29
    (18.6,0.38)
    213
    0.41
    (14.8,0.31)
    164
    0.34
    (19.7,0.39)
    192
    0.33
    (14.8,0.34)
    184
    0.23
    (17.0,0.35)
    194
    0.26
    (15.3,0.34)
    208
    1.00
    (0.0, 0.00)
    221
    
    
    
    
    J
    0.70
    (10.5,0.21)
    804
    0.74
    (11.9,0.19)
    292
    0.82
    (9.4,0.16)
    920
    0.64
    (9.6,0.21)
    274
    0.88
    (8.2,0.15)
    307
    0.69
    (9.8,0.19)
    311
    0.92
    (5.4,0.12)
    882
    0.91
    (5.9,0.12)
    914
    0.21
    (18.3,0.35)
    205
    1.00
    (0.0, 0.00)
    999
    
    K
    0.82
    (11.4,0.23)
    259
    0.71
    (15.0,0.27)
    277
    0.78
    (13.2,0.25)
    305
    0.60
    (11.6,0.23)
    261
    0.76
    (13.7,0.27)
    291
    0.72
    (9.9,0.21)
    293
    0.78
    (11.0,0.21)
    277
    0.78
    (9.5,0.21)
    294
    0.31
    (9.7, 0.28)
    180
    0.84
    (9.8,0.19)
    298
    1.00
    (0.0, 0.00)
    318
    
    0 8 -
    
    c
    o
    1
    I
    
    n -
    *• * \
    • •' '
    » «
    «
    ~ * *
    4
    
    
    • *
    • •
    
    
    
    «*
    
    
    
    *
    
    
    
    
    
    
    
    
    
    «*. .
    
    
                     10       20       30      40      50      60      70
    
                                           Distance Between Samplers (km)
                                                                            80
                                                                                    90
                                                                                            100
    Figure A-60.   PM2.s inter-sampler correlations as a function of distance between monitors for
                   Los Angeles, CA.
    December 2009
    A-127
    

    -------
                     New York Combined Statistical Area
           5/1
    
                        |	| New York CSA
                         •  PM2.5 Monitors
                        	 Interstate Highways
                           — Major Highways
    
      0 10 20   40   60   80   100
                             i Kilometers
    Figure A-61.  PM2.s monitor distribution and major highways, New York City, NY.
    December 2009
    A-128
    

    -------
    
    Site A
    SiteB
    SiteC
    SiteD
    SiteE
    SiteF
    SiteG
    SiteH
    Sitel
    SiteJ
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    SiteK
    SiteL
    SiteM
    SiteN
    SiteO
    SiteP
    SiteQ
    SiteR
    SiteS
    Site!
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    AQS Site ID A
    09-001-0010 .,
    Mean 132
    09-001-1123
    09-001-3005 Obs 349
    09-001-9003 SD 8.7
    09-005-0005 50 -
    09-009-0026
    09-009-0027
    09-009-1123
    09-009-2008 40 -
    09-009-2123
    "E
    -- 30 -
    Ol
    c
    o
    4-1
    TO
    - 20-
    c
    u
    c
    o
    10 -
    1=winter
    2=spring
    3=summer 0 -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    4=fall 1234
    AQS Site ID
    K
    34-003-0003
    34-013-0015 Mean 13'2
    34-017-1003 Obs 345
    34-021-0008 SD 89
    34-021-8001 50 -
    34-023-0006
    34-027-0004
    34-027-3001
    34-029-2002 4Q _
    34-031-0005
    "E
    -- 30 -
    Ol
    IL
    C
    O
    S 20 -
    e
    01
    u
    c
    o
    u
    10 -
    1=winter
    2=spring
    3=summer
    A fi\\ ^
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    A B C D
    i 13.2 12.5 12.3 11.2
    s 349 339 332 565
    3 8.7 8.3 8.1 7.6
    
    
    
    
    
    
    
    E F G H J
    8.0 12.1 12.4 12.8 11.1 12.6
    341 341 992 338 344 352
    6.8 8.0 8.1 8.6 7.5 8.2
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                               1234   1234   1234  1234  1234   1234  1234  1234   1234   1234
    K L M N 0 P
    13.2 13.3 13.7 12.3 10.8 12.1
    345 334 559 545 313 336
    8.9 8.8 8.5 7.7 7.0 7.7
    
    
    
    
    
    
    
    Q R S T
    11.3 10.0 10.6 12.9
    336 357 550 330
    7.7 7.4 6.8 8.7
    
    
    
    
    
    
    
    
    
    
                              1234   1234  1234  1234   1234   1234  1234  1234   1234  1234
    December 2009
    A-129
    

    -------
                       AQS Site ID
                 SiteU  34-039-0004   Mea|1
                 Site V  34-039-0006
                 SiteW  34-039-2003
                 Site X  36-005-0080
                 SiteY  36-005-0083
                 SiteZ  36-005-0110
                 SiteAA  36-047-0122
                 SiteAB  36-059-0008
                 Site AC  36-061-0056
                 Site AD  36-061-0079
                          l=winter
                          2=spring
                          3=summei
                          4=fall
    U V W X Y Z AA AB AC AD
    Mean 14.5 13.2 12.9 15.5 13.0 13.0 14.0 11.4 15.9 13.5
    Obs 1017 352 332 349 359 1059 342 337 357 363
    SD 8.7 8.4 8.4 9.1 8.2 8.2 8.4 7.5 8.9 8.4
    50 -
    40 -
    30 -
    20 -
    10 -
    r 0 -
    
    
    
    
    
    
    
    
    
    
    
    
                                      1234  1234  1234  1234 1234  1234  1234  1234  1234  1234
    SiteAE 36-061-0128 AE AF AG AH AI AJ
    SiteAF 36-071-0002 Mean 15.3 10.8 US 13.3 11. 4 11.7
    SiteAG 36-081-0124 Obs 341 342 951 337 335 355
    Site AH 36-085-0055 SD 8.8 7.6 7.5 s.o 7.3 7.8
    SiteAl 36-085-0067 50 -
    SiteAJ 36-119-1002
    40 -
    IE
    Dl
    a 30-
    c
    o
    •*-»
    ro
    •*-*
    Ł 20 -
    u
    c
    o
    u
    10 -
    1=winter
    2=spring
    3=summer 0 -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Figure A-62.    Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                      for New York, NY.
    December  2009
    A-130
    

    -------
    Table A-28.   Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
                 New York, NY.
    Site A B
    A 1.00 0.89
    (0.0,0.00) (5.3,0.15)
    349 322
    B 1.00
    (0.0, 0.00)
    339
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    
    
    J
    
    
    K
    
    
    L
    
    
    M
    
    
    N
    
    
    0
    
    
    P
    
    
    Q
    
    
    R
    C D E F
    0.97 0.97 0.82 0.96
    (3.6,0.09) (4.8,0.11) (11.8,0.33) (3.8,0.11)
    316 322 325 328
    0.93 0.91 0.78 0.91
    (4.5,0.13) (5.3,0.14) (10.4,0.32) (4.7,0.13)
    312 315 319 316
    1.00 0.98 0.82 0.96
    (0.0,0.00) (3.4,0.08) (10.8,0.32) (3.9,0.10)
    332 314 309 310
    1.00 0.85 0.96
    (0.0,0.00) (8.4,0.29) (3.4,0.11)
    565 314 316
    1.00 0.82
    (0.0,0.00) (10.0,0.31)
    341 321
    1.00
    (0.0, 0.00)
    341
    
    
    
    
    
    
    
    
    
    
    
    1 PftPND
    R
    
    (rUU, (sUU)
    N
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    G
    0.96
    (4.0,0.11)
    321
    0.92
    (4.6,0.13)
    313
    0.95
    (4.1,0.11)
    308
    0.96
    (3.8,0.11)
    532
    0.82
    (10.7,0.33)
    313
    0.99
    (2.1,0.07)
    314
    1.00
    (0.0, 0.00)
    992
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    H
    0.96
    (3.4,0.10)
    324
    0.91
    (4.6,0.14)
    313
    0.96
    (3.6,0.10)
    307
    0.94
    (5.0,0.13)
    315
    0.79
    (11.4,0.33)
    317
    0.98
    (2.9, 0.09)
    319
    0.96
    (2.9,0.10)
    315
    1.00
    (0.0, 0.00)
    338
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    0.96
    (4.6,0.12)
    326
    0.91
    (5.0, 0.14)
    315
    0.97
    (4.0,0.11)
    310
    0.96
    (3.0,0.10)
    313
    0.83
    (8.8, 0.28)
    319
    0.98
    (2.8, 0.09)
    321
    0.98
    (3.6,0.11)
    319
    0.98
    (3.7,0.10)
    320
    1.00
    (0.0, 0.00)
    344
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    J
    0.93
    (5.1,0.12)
    335
    0.92
    (4.5,0.13)
    330
    0.94
    (4.8,0.11)
    319
    0.92
    (5.5,0.13)
    325
    0.81
    (10.3,0.32)
    330
    0.94
    (4.7,0.11)
    328
    0.93
    (5.2,0.12)
    326
    0.94
    (3.7,0.10)
    324
    0.95
    (4.1,0.11)
    327
    1.00
    (0.0, 0.00)
    352
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    K
    0.91
    (5.8,0.12)
    329
    0.83
    (7.3,0.17)
    319
    0.91
    (5.7,0.13)
    314
    0.90
    (7.1,0.15)
    319
    0.80
    (12.5,0.34)
    322
    0.88
    (6.7, 0.14)
    321
    0.88
    (7.1,0.15)
    319
    0.88
    (7.1,0.14)
    318
    0.89
    (7.0,0.16)
    324
    0.87
    (7.0,0.16)
    332
    1.00
    (0.0, 0.00)
    345
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    L
    0.91
    (5.7,0.12)
    316
    0.84
    (7.1,0.17)
    305
    0.91
    (5.8,0.14)
    299
    0.89
    (6.9,0.15)
    308
    0.77
    (13.0,0.34)
    305
    0.89
    (6.8,0.15)
    308
    0.89
    (6.7,0.15)
    309
    0.89
    (7.1,0.14)
    303
    0.90
    (7.0,0.16)
    307
    0.87
    (7.2,0.16)
    316
    0.95
    (3.4, 0.09)
    314
    1.00
    (0.0, 0.00)
    334
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    M
    0.92
    (5.5,0.13)
    331
    0.85
    (7.8,0.19)
    321
    0.91
    (6.5,0.15)
    316
    0.91
    (6.7,0.18)
    517
    0.76
    (13.8,0.39)
    323
    0.89
    (6.8,0.16)
    323
    0.89
    (6.9,0.16)
    526
    0.89
    (6.6,0.16)
    321
    0.89
    (7.7, 0.20)
    323
    0.87
    (8.5,0.17)
    334
    0.93
    (4.5,0.12)
    330
    0.97
    (4.1,0.10)
    321
    1.00
    (0.0, 0.00)
    559
    
    
    
    
    
    
    
    
    
    
    
    
    
    N
    0.88
    (6.6,0.16)
    301
    0.82
    (7.2,0.19)
    291
    0.89
    (5.4,0.15)
    287
    0.88
    (6.3,0.17)
    506
    0.76
    (11.6,0.35)
    294
    0.86
    (6.4,0.17)
    293
    0.84
    (6.9,0.18)
    513
    0.84
    (6.7,0.18)
    292
    0.87
    (6.4,0.18)
    296
    0.84
    (6.9,0.18)
    303
    0.88
    (6.4,0.15)
    301
    0.91
    (6.4, 0.14)
    289
    0.91
    (5.5, 0.14)
    499
    1.00
    (0.0, 0.00)
    545
    
    
    
    
    
    
    
    
    
    
    0
    0.84
    (9.1,0.19)
    296
    0.79
    (7.7, 0.20)
    292
    0.84
    (6.9,0.17)
    289
    0.87
    (6.5,0.16)
    288
    0.79
    (9.1,0.30)
    291
    0.85
    (6.8,0.18)
    295
    0.84
    (8.0,0.19)
    286
    0.82
    (8.1,0.20)
    285
    0.85
    (6.6,0.17)
    291
    0.79
    (7.9, 0.20)
    299
    0.86
    (7.5,0.17)
    296
    0.86
    (8.0,0.18)
    288
    0.86
    (8.4,0.21)
    300
    0.93
    (4.7, 0.14)
    270
    1.00
    (0.0, 0.00)
    313
    
    
    
    
    
    
    
    P
    0.87
    (8.3,0.16)
    321
    0.82
    (7.6,0.18)
    310
    0.88
    (6.3, 0.14)
    307
    0.89
    (6.0,0.15)
    311
    0.78
    (10.4,0.32)
    316
    0.88
    (6.1,0.15)
    312
    0.86
    (7.6,0.16)
    310
    0.85
    (7.8,0.17)
    310
    0.87
    (6.5,0.16)
    313
    0.82
    (8.1,0.18)
    321
    0.90
    (5.7,0.13)
    317
    0.94
    (5.2,0.12)
    309
    0.93
    (6.7,0.15)
    326
    0.95
    (4.1,0.11)
    293
    0.93
    (4.3,0.12)
    294
    1.00
    (0.0, 0.00)
    336
    
    
    
    
    Q
    0.89
    (7.6,0.16)
    318
    0.82
    (6.6,0.18)
    307
    0.89
    (6.2,0.15)
    305
    0.90
    (5.5,0.14)
    309
    0.87
    (7.9, 0.28)
    311
    0.87
    (7.3,0.16)
    310
    0.87
    (8.1,0.17)
    306
    0.85
    (7.5,0.17)
    307
    0.88
    (6.5,0.15)
    313
    0.84
    (7.5,0.17)
    322
    0.92
    (5.8,0.14)
    319
    0.93
    (5.9,0.13)
    303
    0.92
    (7.5,0.18)
    318
    0.91
    (5.8,0.15)
    292
    0.91
    (4.9, 0.14)
    287
    0.94
    (4.9,0.12)
    308
    1.00
    (0.0, 0.00)
    336
    
    R
    0.84
    (9.3,0.21)
    316
    0.78
    (8.4, 0.22)
    305
    0.84
    (8.2, 0.20)
    297
    0.86
    (6.6,0.18)
    330
    0.87
    (7.3, 0.24)
    305
    0.83
    (7.5,0.21)
    308
    0.82
    (8.4, 0.23)
    327
    0.79
    (9.2, 0.23)
    304
    0.83
    (7.6,0.19)
    310
    0.79
    (9.0, 0.22)
    316
    0.86
    (8.7, 0.20)
    312
    0.87
    (8.3, 0.20)
    301
    0.85
    (9.7, 0.25)
    337
    0.88
    (7.2, 0.20)
    316
    0.94
    (4.3,0.14)
    279
    0.91
    (5.5,0.16)
    303
    0.95
    (3.8,0.13)
    307
    1.00
    (0.0, 0.00)
    357
    December 2009                                  A-131
    

    -------
    s
    A 075
    (10.4,0.21)
    323
    B 0.68
    (10.8,0.23)
    314
    C 0.76
    (8.5, 0.20)
    307
    D 0.80
    (7.7,0.19)
    509
    E 0.67
    (9.8, 0.32)
    315
    F 0.79
    (7.9,0.19)
    316
    G 0.77
    (8.7,0.21)
    513
    H 0.74
    (9.6, 0.22)
    314
    I 0.76
    (8.1,0.20)
    315
    J 0.67
    (11.1,0.22)
    327
    K 0.74
    (10.9,0.21)
    320
    L 0.78
    (9.8, 0.20)
    313
    M 0.80
    (9.9, 0.22)
    504
    N 0.88
    (6.4,0.17)
    492
    0 0.87
    (5.6,0.16)
    295
    P 0.86
    (6.2,0.15)
    312
    Q 0.79
    (8.1,0.19)
    313
    R 0.82
    (6.5, 0.20)
    330
    S 1.00
    (0.0, 0.00)
    550
    T
    
    
    U
    
    
    V
    
    
    W
    
    
    X
    
    
    Y
    
    
    Z
    
    
    AA
    
    
    AB
    
    
    AC
    
    
    AD
    
    
    AE
    T
    0.89
    (6.1,0.13)
    315
    0.84
    (5.9,0.16)
    307
    0.89
    (6.1,0.14)
    304
    0.88
    (7.3,0.16)
    306
    0.79
    (11.3,0.34)
    306
    0.87
    (6.7,0.15)
    306
    0.87
    (6.3,0.15)
    304
    0.86
    (6.6,0.15)
    304
    0.88
    (7.1,0.17)
    308
    0.84
    (6.6,0.16)
    316
    0.94
    (3.9,0.11)
    317
    0.94
    (3.9,0.11)
    303
    0.93
    (5.4,0.13)
    318
    0.86
    (6.5,0.16)
    287
    0.82
    (7.2,0.18)
    289
    0.89
    (6.2,0.14)
    307
    0.92
    (5.0,0.14)
    303
    0.86
    (7.6,0.21)
    296
    0.69
    (10.4,0.22)
    306
    1.00
    (0.0, 0.00)
    330
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    U
    0.90
    (7.1,0.15)
    337
    0.83
    (8.6, 0.20)
    328
    0.88
    (7.8,0.18)
    321
    0.88
    (8.1,0.20)
    537
    0.74
    (14.9, 0.40)
    329
    0.86
    (8.5,0.19)
    329
    0.87
    (7.8,0.18)
    928
    0.86
    (8.4,0.18)
    326
    0.87
    (8.7,0.21)
    332
    0.85
    (9.0,0.19)
    343
    0.92
    (5.7,0.14)
    336
    0.97
    (4.5,0.12)
    325
    0.97
    (3.8, 0.09)
    534
    0.90
    (6.5,0.15)
    519
    0.86
    (9.9, 0.22)
    302
    0.92
    (7.4,0.17)
    325
    0.91
    (8.2, 0.20)
    327
    0.84
    (10.9,0.26)
    347
    0.77
    (10.5,0.24)
    525
    0.92
    (6.0,0.15)
    319
    1.00
    (0.0, 0.00)
    1017
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    V
    0.90
    (6.0,0.13)
    299
    0.83
    (6.5,0.18)
    290
    0.89
    (6.4,0.15)
    283
    0.87
    (7.1,0.17)
    326
    0.76
    (11.7,0.36)
    290
    0.86
    (6.8,0.16)
    293
    0.86
    (7.0,0.16)
    327
    0.87
    (7.1,0.16)
    289
    0.88
    (7.4,0.17)
    293
    0.86
    (6.7,0.16)
    301
    0.95
    (3.4,0.10)
    302
    0.98
    (2.9, 0.08)
    292
    0.97
    (3.5, 0.09)
    341
    0.91
    (5.7,0.13)
    313
    0.87
    (7.3,0.18)
    280
    0.94
    (5.0,0.12)
    296
    0.93
    (6.2,0.14)
    287
    0.85
    (8.2,0.21)
    291
    0.75
    (10.5,0.21)
    324
    0.93
    (4.5,0.12)
    293
    0.98
    (3.9,0.10)
    341
    1.00
    (0.0, 0.00)
    352
    
    
    
    
    
    
    
    
    
    
    
    
    
    LEC
    (P90,
    
    
    
    
    
    
    
    w
    0.88
    (7.2,0.15)
    316
    0.84
    (6.8,0.18)
    305
    0.89
    (6.0,0.15)
    297
    0.88
    (6.9,0.17)
    304
    0.75
    (12.1,0.36)
    307
    0.87
    (6.6,0.16)
    309
    0.88
    (6.3,0.15)
    303
    0.87
    (6.9,0.16)
    306
    0.88
    (6.9,0.17)
    309
    0.86
    (6.8,0.17)
    318
    0.92
    (4.3,0.12)
    317
    0.95
    (4.0,0.10)
    303
    0.96
    (4.7,0.11)
    319
    0.91
    (4.5,0.13)
    290
    0.88
    (6.4,0.16)
    284
    0.95
    (4.0,0.11)
    305
    0.92
    (5.4,0.15)
    304
    0.87
    (7.0, 0.20)
    304
    0.78
    (9.2,0.19)
    306
    0.93
    (4.8,0.13)
    301
    0.97
    (5.0,0.12)
    325
    0.97
    (2.8, 0.09)
    288
    1.00
    (0.0, 0.00)
    332
    
    
    
    
    
    
    
    
    
    
    SEND
    R
    , COD)
    N
    
    
    
    
    
    
    
    X
    0.92
    (7.2,0.16)
    332
    0.84
    (9.0,0.21)
    325
    0.92
    (7.8,0.18)
    317
    0.89
    (9.7,0.21)
    324
    0.75
    (15.2,0.41)
    324
    0.89
    (8.2,0.19)
    325
    0.89
    (8.3,0.17)
    319
    0.90
    (7.5,0.17)
    322
    0.90
    (9.4, 0.22)
    326
    0.88
    (8.8,0.19)
    337
    0.92
    (6.0,0.15)
    330
    0.94
    (6.3,0.15)
    314
    0.95
    (4.9,0.11)
    331
    0.86
    (8.2,0.18)
    301
    0.84
    (11.1,0.24)
    299
    0.88
    (8.9,0.19)
    319
    0.89
    (9.7, 0.22)
    321
    0.82
    (11.6,0.28)
    314
    0.72
    (12.5,0.25)
    325
    0.92
    (6.7,0.16)
    313
    0.92
    (5.4,0.12)
    337
    0.93
    (6.1,0.14)
    300
    0.90
    (7.0,0.16)
    316
    1.00
    (0.0, 0.00)
    349
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Y
    0.94
    (4.0,0.11)
    342
    0.88
    (5.9,0.16)
    334
    0.95
    (4.4,0.11)
    326
    0.94
    (5.6, 0.14)
    332
    0.80
    (11.5,0.34)
    334
    0.93
    (5.0,0.12)
    335
    0.92
    (5.4,0.13)
    329
    0.92
    (5.2,0.13)
    331
    0.93
    (5.7,0.15)
    334
    0.90
    (6.1,0.14)
    345
    0.93
    (3.8,0.12)
    339
    0.93
    (4.5,0.12)
    323
    0.95
    (4.7,0.12)
    342
    0.90
    (5.9, 0.14)
    309
    0.87
    (6.7,0.18)
    308
    0.90
    (5.9, 0.14)
    329
    0.90
    (6.3,0.16)
    328
    0.87
    (8.6,0.21)
    323
    0.78
    (8.6,0.19)
    336
    0.91
    (5.2,0.14)
    323
    0.91
    (6.9,0.15)
    347
    0.92
    (5.0,0.13)
    307
    0.91
    (5.5,0.13)
    325
    0.96
    (5.8,0.13)
    344
    1.00
    (0.0, 0.00)
    359
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Z
    0.93
    (4.7,0.12)
    348
    0.85
    (6.8,0.17)
    338
    0.93
    (5.4,0.13)
    331
    0.92
    (6.2,0.15)
    548
    0.78
    (13.1,0.36)
    340
    0.91
    (6.4,0.14)
    340
    0.90
    (5.7,0.14)
    958
    0.89
    (5.6,0.14)
    337
    0.92
    (6.5,0.16)
    343
    0.88
    (7.1,0.16)
    351
    0.92
    (4.2,0.12)
    344
    0.94
    (4.2,0.11)
    333
    0.96
    (3.5,0.10)
    545
    0.89
    (5.4,0.15)
    529
    0.86
    (8.6,0.19)
    312
    0.89
    (6.8,0.15)
    335
    0.90
    (7.3,0.17)
    335
    0.84
    (10.0,0.23)
    355
    0.79
    (9.3,0.21)
    536
    0.91
    (4.9,0.13)
    329
    0.93
    (5.2,0.13)
    987
    0.92
    (4.4,0.12)
    351
    0.91
    (5.3,0.13)
    331
    0.97
    (4.4,0.11)
    349
    0.97
    (3.2, 0.08)
    359
    1.00
    (0.0, 0.00)
    1059
    
    
    
    
    
    
    
    
    
    
    
    
    
    AA
    0.93
    (5.5,0.13)
    325
    0.84
    (7.3,0.18)
    317
    0.92
    (5.6,0.15)
    311
    0.91
    (7.0,0.17)
    315
    0.76
    (13.9,0.38)
    319
    0.90
    (6.7,0.15)
    320
    0.90
    (7.1,0.15)
    315
    0.90
    (6.4,0.15)
    315
    0.91
    (7.2,0.18)
    323
    0.86
    (7.3,0.17)
    330
    0.93
    (4.3,0.12)
    324
    0.95
    (4.1,0.11)
    306
    0.97
    (3.4, 0.09)
    326
    0.91
    (5.3,0.14)
    297
    0.88
    (8.2, 0.20)
    292
    0.92
    (6.4,0.14)
    312
    0.90
    (7.3,0.18)
    314
    0.86
    (9.1,0.24)
    309
    0.82
    (9.4, 0.20)
    319
    0.90
    (5.6,0.14)
    308
    0.94
    (4.9,0.12)
    332
    0.94
    (4.2,0.12)
    294
    0.92
    (4.8,0.13)
    310
    0.95
    (5.0,0.11)
    328
    0.96
    (3.9, 0.09)
    338
    0.97
    (2.9, 0.09)
    342
    1.00
    (0.0, 0.00)
    342
    
    
    
    
    
    
    
    
    
    
    AB
    0.88
    (7.6,0.18)
    320
    0.81
    (7.9, 0.20)
    313
    0.89
    (6.1,0.16)
    306
    0.89
    (5.9,0.16)
    313
    0.73
    (10.1,0.33)
    314
    0.90
    (5.6,0.16)
    317
    0.88
    (7.5,0.17)
    308
    0.88
    (7.3,0.19)
    310
    0.87
    (6.2,0.17)
    313
    0.81
    (8.2,0.19)
    324
    0.84
    (8.5,0.19)
    318
    0.86
    (8.1,0.18)
    305
    0.88
    (8.3, 0.20)
    320
    0.89
    (5.6,0.17)
    289
    0.89
    (5.2,0.15)
    295
    0.89
    (5.3,0.14)
    309
    0.83
    (6.9,0.19)
    306
    0.83
    (7.0,0.21)
    301
    0.88
    (5.0,0.16)
    314
    0.80
    (8.4, 0.20)
    303
    0.84
    (9.9, 0.22)
    326
    0.83
    (8.2,0.19)
    290
    0.85
    (7.0,0.18)
    309
    0.86
    (10.0,0.23)
    324
    0.90
    (6.5,0.16)
    333
    0.90
    (7.2,0.17)
    337
    0.92
    (7.1,0.18)
    317
    1.00
    (0.0, 0.00)
    337
    
    
    
    
    
    
    
    AC
    0.89
    (7.3,0.18)
    340
    0.81
    (8.4, 0.22)
    331
    0.88
    (7.5, 0.20)
    325
    0.87
    (9.6, 0.23)
    330
    0.74
    (15.7,0.43)
    332
    0.87
    (8.4, 0.20)
    334
    0.86
    (8.1,0.19)
    327
    0.87
    (7.9,0.19)
    329
    0.87
    (9.6, 0.24)
    332
    0.85
    (9.0,0.21)
    343
    0.90
    (6.2,0.17)
    338
    0.91
    (6.3,0.17)
    322
    0.94
    (4.5,0.12)
    339
    0.85
    (8.1,0.18)
    308
    0.82
    (10.3,0.25)
    307
    0.87
    (8.9,0.21)
    327
    0.90
    (9.9, 0.24)
    329
    0.81
    (11.2,0.30)
    324
    0.74
    (11.6,0.26)
    333
    0.87
    (6.9,0.18)
    321
    0.91
    (5.0,0.12)
    346
    0.90
    (6.6,0.16)
    305
    0.89
    (6.8,0.17)
    323
    0.94
    (3.3, 0.09)
    342
    0.93
    (5.4,0.15)
    352
    0.94
    (4.4,0.13)
    357
    0.94
    (3.8,0.11)
    336
    0.85
    (9.2, 0.24)
    330
    1.00
    (0.0, 0.00)
    357
    
    
    
    
    AD
    0.94
    (4.4,0.11)
    346
    0.86
    (7.0,0.17)
    336
    0.93
    (5.3,0.12)
    330
    0.92
    (6.6,0.15)
    336
    0.79
    (13.1,0.35)
    338
    0.91
    (6.3,0.14)
    339
    0.91
    (6.4,0.14)
    333
    0.91
    (5.7,0.13)
    335
    0.92
    (6.3,0.16)
    338
    0.89
    (6.9,0.15)
    349
    0.93
    (3.8,0.11)
    343
    0.95
    (4.2,0.10)
    327
    0.96
    (3.5,0.10)
    345
    0.90
    (5.3,0.14)
    313
    0.88
    (8.4,0.18)
    311
    0.91
    (6.4,0.14)
    333
    0.91
    (6.9,0.16)
    332
    0.86
    (9.5, 0.22)
    327
    0.78
    (9.9, 0.20)
    339
    0.93
    (4.9,0.12)
    327
    0.94
    (5.2,0.12)
    351
    0.94
    (4.3,0.11)
    311
    0.93
    (5.0,0.12)
    328
    0.97
    (4.5,0.11)
    348
    0.98
    (2.8, 0.08)
    358
    0.98
    (1.8,0.07)
    363
    0.98
    (2.9, 0.07)
    341
    0.89
    (7.2,0.17)
    337
    0.95
    (4.4,0.13)
    356
    1.00
    (0.0, 0.00)
    363
    
    AE
    0.88
    (7.2,0.19)
    326
    0.81
    (8.8, 0.23)
    315
    0.88
    (7.4, 0.20)
    308
    0.85
    (9.2, 0.23)
    315
    0.70
    (15.0,0.42)
    316
    0.86
    (8.0,0.21)
    319
    0.85
    (8.2, 0.20)
    314
    0.86
    (7.3, 0.20)
    313
    0.86
    (9.2, 0.24)
    318
    0.84
    (8.9, 0.22)
    327
    0.88
    (6.2,0.18)
    321
    0.91
    (5.9,0.17)
    309
    0.93
    (4.5,0.13)
    326
    0.85
    (7.7,0.18)
    294
    0.81
    (10.6,0.25)
    290
    0.87
    (8.3, 0.20)
    313
    0.87
    (9.5, 0.24)
    311
    0.78
    (11.0,0.30)
    309
    0.73
    (11.5,0.25)
    322
    0.85
    (7.2, 0.20)
    306
    0.90
    (5.9,0.14)
    330
    0.91
    (6.1,0.16)
    294
    0.88
    (6.9,0.18)
    308
    0.93
    (4.1,0.11)
    326
    0.93
    (5.4,0.15)
    337
    0.92
    (4.6,0.14)
    341
    0.93
    (4.1,0.11)
    319
    0.86
    (9.0, 0.23)
    316
    0.98
    (3.0, 0.08)
    334
    0.93
    (4.6, 0.14)
    341
    1.00
    AF
    0.89
    (6.7,0.16)
    323
    0.92
    (5.8,0.16)
    316
    0.89
    (6.7,0.15)
    312
    0.90
    (5.4, 0.14)
    313
    0.88
    (7.6, 0.26)
    316
    0.89
    (6.4,0.16)
    317
    0.88
    (6.7,0.17)
    311
    0.88
    (6.9,0.17)
    313
    0.90
    (5.5,0.13)
    319
    0.90
    (6.4,0.16)
    329
    0.89
    (7.4,0.17)
    321
    0.89
    (6.8,0.17)
    306
    0.88
    (8.5,0.21)
    323
    0.85
    (7.5, 0.20)
    292
    0.84
    (7.0,0.18)
    290
    0.87
    (6.7,0.16)
    311
    0.91
    (4.8, 0.14)
    312
    0.88
    (6.2,0.17)
    308
    0.69
    (10.3,0.22)
    316
    0.89
    (6.3,0.17)
    308
    0.86
    (9.6, 0.23)
    330
    0.88
    (7.0,0.18)
    290
    0.87
    (6.8,0.18)
    310
    0.88
    (9.8, 0.24)
    326
    0.89
    (6.5,0.18)
    335
    0.88
    (7.8,0.19)
    342
    0.87
    (8.1,0.20)
    319
    0.79
    (8.1,0.20)
    313
    0.84
    (10.4,0.26)
    336
    0.89
    (7.1,0.18)
    339
    0.82
    AG
    0.93
    (5.1,0.12)
    299
    0.84
    (6.6,0.17)
    292
    0.93
    (4.7,0.11)
    282
    0.92
    (4.8,0.12)
    496
    0.77
    (11.3,0.32)
    294
    0.93
    (4.6,0.12)
    290
    0.90
    (5.2,0.13)
    856
    0.90
    (5.6,0.14)
    290
    0.93
    (5.1,0.14)
    296
    0.88
    (6.4,0.15)
    301
    0.90
    (5.9,0.13)
    294
    0.92
    (5.4,0.12)
    283
    0.95
    (5.0,0.14)
    484
    0.91
    (4.9,0.14)
    477
    0.88
    (6.1,0.16)
    269
    0.91
    (5.5,0.13)
    285
    0.89
    (6.0,0.15)
    287
    0.86
    (7.6, 0.20)
    304
    0.85
    (7.2,0.17)
    478
    0.88
    (6.2, 0.14)
    281
    0.90
    (6.9,0.17)
    878
    0.89
    (5.8,0.15)
    301
    0.89
    (5.1,0.14)
    281
    0.93
    (6.9,0.17)
    301
    0.97
    (3.3, 0.09)
    308
    0.95
    (4.0,0.10)
    919
    0.97
    (4.0,0.11)
    292
    0.95
    (4.1,0.13)
    291
    0.96
    (6.6,0.18)
    304
    0.97
    (4.0,0.10)
    311
    0.94
    AH
    0.90
    (6.2,0.15)
    317
    0.87
    (6.8,0.18)
    311
    0.91
    (5.7,0.14)
    305
    0.90
    (6.5,0.16)
    308
    0.75
    (12.5,0.36)
    310
    0.89
    (5.7,0.15)
    312
    0.89
    (6.1,0.15)
    312
    0.88
    (6.8,0.16)
    308
    0.89
    (6.7,0.18)
    310
    0.87
    (7.5,0.16)
    321
    0.91
    (5.0,0.13)
    318
    0.96
    (4.0,0.11)
    305
    0.96
    (4.3,0.10)
    319
    0.92
    (4.6,0.13)
    292
    0.89
    (6.1,0.18)
    290
    0.94
    (4.7,0.12)
    307
    0.90
    (6.3,0.17)
    303
    0.87
    (7.8, 0.22)
    298
    0.82
    (8.5,0.18)
    310
    0.90
    (5.8,0.14)
    306
    0.96
    (5.8,0.12)
    325
    0.96
    (4.0,0.10)
    291
    0.96
    (3.7,0.10)
    304
    0.92
    (6.5,0.14)
    319
    0.93
    (4.9,0.12)
    328
    0.93
    (4.7,0.11)
    337
    0.95
    (4.3,0.10)
    313
    0.90
    (6.1,0.16)
    310
    0.91
    (6.6,0.15)
    326
    0.95
    (4.4,0.10)
    333
    0.92
    Al
    0.89
    (7.5,0.16)
    318
    0.86
    (7.1,0.18)
    309
    0.89
    (6.0,0.15)
    302
    0.91
    (5.3,0.14)
    310
    0.80
    (9.4,0.31)
    309
    0.89
    (5.3,0.15)
    310
    0.88
    (6.1,0.16)
    309
    0.86
    (6.4,0.17)
    308
    0.89
    (5.8,0.16)
    311
    0.84
    (7.7,0.18)
    320
    0.89
    (6.5,0.15)
    314
    0.92
    (6.4,0.14)
    299
    0.93
    (6.8,0.16)
    318
    0.92
    (5.3,0.14)
    293
    0.92
    (4.7,0.14)
    283
    0.95
    (3.5,0.10)
    306
    0.91
    (5.3,0.14)
    302
    0.90
    (5.7,0.17)
    302
    0.88
    (5.5,0.14)
    312
    0.86
    (7.3,0.17)
    298
    0.91
    (8.4,0.18)
    323
    0.91
    (6.4,0.15)
    287
    0.92
    (4.9,0.13)
    303
    0.88
    (9.2, 0.20)
    319
    0.92
    (5.3,0.13)
    329
    0.91
    (6.1,0.14)
    335
    0.94
    (6.6,0.15)
    312
    0.93
    (3.8,0.12)
    310
    0.89
    (9.3,0.21)
    326
    0.93
    (6.0,0.13)
    333
    0.89
    AJ
    0.96
    (4.4,0.12)
    338
    0.88
    (5.5,0.15)
    329
    0.96
    (3.5,0.10)
    322
    0.96
    (3.7,0.10)
    328
    0.84
    (9.8, 0.29)
    331
    0.94
    (4.1,0.12)
    332
    0.93
    (5.0,0.14)
    325
    0.93
    (5.0,0.13)
    327
    0.94
    (4.1,0.12)
    330
    0.91
    (5.6,0.14)
    341
    0.92
    (4.8,0.13)
    335
    0.92
    (5.4,0.13)
    319
    0.93
    (5.7,0.17)
    338
    0.90
    (5.4,0.16)
    306
    0.88
    (5.4,0.16)
    304
    0.91
    (5.0,0.14)
    326
    0.92
    (5.5,0.13)
    324
    0.88
    (6.3,0.17)
    320
    0.79
    (8.1,0.19)
    331
    0.91
    (5.9,0.14)
    319
    0.90
    (7.5,0.19)
    343
    0.91
    (5.3,0.15)
    304
    0.90
    (5.0,0.15)
    320
    0.93
    (8.2,0.19)
    340
    0.97
    (3.5,0.11)
    350
    0.95
    (4.9,0.14)
    355
    0.95
    (5.1,0.15)
    335
    0.90
    (5.5,0.16)
    329
    0.91
    (7.4, 0.22)
    348
    0.96
    (4.6,0.13)
    354
    0.89
    December 2009                                      A-132
    

    -------
    s
    
    
    AF
    
    
    AG
    
    
    AH
    
    
    Al
    
    
    AJ
    T U V W X Y Z AA AB AC AD AE AF
    (0.0,0.00) (10.0,0.26)
    341 319
    1.00
    (0.0, 0.00)
    342
    
    
    
    
    
    
    
    
    
    
    AG
    (6.2,0.18)
    290
    0.86
    (7.0,0.16)
    289
    1.00
    (0.0, 0.00)
    951
    
    
    
    
    
    
    
    AH
    (5.6,0.15)
    313
    0.87
    (7.1,0.18)
    310
    0.93
    (4.8,0.12)
    289
    1.00
    (0.0, 0.00)
    337
    
    
    
    
    Al
    (8.4, 0.20)
    314
    0.87
    (6.4,0.16)
    313
    0.94
    (4.5,0.11)
    283
    0.97
    (4.1,0.10)
    307
    1.00
    (0.0, 0.00)
    335
    
    AJ
    (8.0, 0.22)
    332
    0.91
    (5.5,0.14)
    331
    0.96
    (3.7,0.11)
    304
    0.92
    (4.9,0.15)
    327
    0.92
    (4.8,0.14)
    324
    1.00
    (0.0, 0.00)
    355
                                                                                          *#
        0.8
        0.6
      o
      13
      o
      O
        0.4
        0.2
                   10       20       30       40       50       60       70
    
                                          Distance Between Samplers (km)
                                                                             80
                                                                                      90
                                                                                              100
    Figure A-63   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                  New York, NY.
    December 2009
    A-133
    

    -------
                  Philadelphia  Combined Statistical Area
            A
           01
                       \ Philadelphia CSA
                    •   PMz.s Monitors
                    	 Interstate Highways
                      — Major Highways
                                    0  10  20     40     60     80
                             100
                            ^Kilometers
    Figure A-64.  PM2.s monitor distribution and major highways, Philadelphia, PA.
    December 2009
    A-134
    

    -------
                            AQSSitelD
                     Site A   10-003-1003
                     SiteB   10-003-1007
                     SiteC   10-003-1012
                     SiteD   10-003-2004
                     SiteE   24-015-0003
                     Site F   34-007-0003
                     SiteG   34-007-1007
                     SiteH   42-017-0012
                   Site I
                   SiteJ
                   SiteK
                   SiteL
                   SiteM
                   SiteN
                   SiteO
                              2=spring
                              3-sur
                              4=fall
    ID
    }°3 Mear
    307 Ob.
    X sc
    303 50 -
    303
    307
    312
    40 -
    Ol
    — 30 -
    _0
    ra
    concent
    CD
    10 -
    ter
    ng
    nmer o -
    ABCDEFGH
    13.4 12,6 13.5 14,7 12.5 13.5 13.5 13.2
    335 346 331 999 348 539 340 317
    7.7 7.4 7.7 8.3 7.4 8.0 8.5 8.2
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                         1234   1234  1234  1234 1234   1234  1234  1234
    AQS Site ID
    J K L M N 0
    42-045-0002 Mean R2 15° 12'6 13'8 12'8 14'9 13'4
    42-091-0013 Obs 277 331 307 890 805 596 780
    42-101-0004 SD 83 3.1 7.7 8.4 8.0 8.3 7.7
    42-101-0024 50 _
    42-101-0047
    42-101-0136
    40 -
    1
    O1
    3 30-
    c
    o
    4->
    ro
    4->
    C
    
    -------
    Table A-29.   Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
                 Philadelphia, PA.
    A B
    A 1.00 0.94
    (0.0,0.00) (4.7,0.12)
    335 305
    B 1.00
    (0.0, 0.00)
    346
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    
    
    J
    
    
    K
    
    
    L
    
    
    M
    
    
    N
    
    
    0
    C D
    0.96 0.98
    (3.1,0.08) (3.2,0.08)
    282 318
    0.95 0.93
    (4.3,0.12) (6.4,0.15)
    288 329
    1.00 0.96
    (0.0, 0.00) (4.3, 0.09)
    331 312
    1.00
    (0.0, 0.00)
    999
    
    
    
    
    
    
    
    
    
    
    
    
    
    LEGEND
    R
    (P90 COD)
    
    
    
    
    
    
    
    
    
    
    
    
    
    E
    0.92
    (4.8,0.12)
    311
    0.94
    (3.4,0.11)
    318
    0.95
    (3.5,0.11)
    289
    0.91
    (6.5,0.15)
    325
    1.00
    (0.0, 0.00)
    348
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    F
    0.96
    (3.5,0.10)
    312
    0.92
    (5.2, 0.14)
    313
    0.94
    (4.7,0.12)
    292
    0.94
    (4.9,0.12)
    490
    0.91
    (5.6,0.14)
    320
    1.00
    (0.0, 0.00)
    539
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    G
    0.93
    (4.2,0.11)
    308
    0.88
    (6.0,0.15)
    315
    0.88
    (5.3,0.14)
    286
    0.92
    (5.0,0.14)
    317
    0.87
    (6.1,0.15)
    321
    0.95
    (3.4, 0.09)
    317
    1.00
    (0.0, 0.00)
    340
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    H
    0.89
    (5.3,0.13)
    289
    0.83
    (6.8,0.17)
    293
    0.88
    (6.0,0.14)
    270
    0.88
    (6.3,0.15)
    297
    0.83
    (6.7,0.16)
    301
    0.90
    (5.3,0.13)
    296
    0.90
    (4.8,0.14)
    295
    1.00
    (0.0, 0.00)
    317
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    0.95
    (4.2,0.12)
    247
    0.90
    (6.7,0.17)
    253
    0.93
    (3.5,0.12)
    242
    0.94
    (4.1,0.12)
    257
    0.90
    (6.6,0.16)
    255
    0.92
    (5.4,0.14)
    261
    0.90
    (5.9,0.16)
    258
    0.84
    (5.7,0.16)
    240
    1.00
    (0.0, 0.00)
    277
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    J
    0.92
    (4.6, 0.14)
    298
    0.87
    (6.5,0.18)
    302
    0.88
    (6.6,0.16)
    278
    0.90
    (5.3,0.14)
    312
    0.86
    (7.1,0.19)
    310
    0.89
    (5.9,0.16)
    309
    0.87
    (6.2,0.17)
    305
    0.83
    (8.0,0.19)
    288
    0.87
    (5.5,0.17)
    248
    1.00
    (0.0, 0.00)
    331
    
    
    
    
    
    
    
    
    
    
    
    
    
    K
    0.86
    (4.7,0.15)
    277
    0.81
    (5.9,0.18)
    285
    0.84
    (5.5,0.17)
    261
    0.85
    (5.8,0.18)
    287
    0.86
    (5.7,0.15)
    287
    0.87
    (4.4,0.15)
    284
    0.85
    (4.7,0.16)
    289
    0.89
    (4.4,0.13)
    275
    0.81
    (5.7,0.17)
    228
    0.79
    (7.4,0.21)
    278
    1.00
    (0.0, 0.00)
    307
    
    
    
    
    
    
    
    
    
    
    L
    0.96
    (3.5, 0.08)
    283
    0.91
    (6.5, 0.14)
    293
    0.93
    (5.0,0.12)
    281
    0.95
    (4.3,0.11)
    801
    0.88
    (6.8,0.15)
    296
    0.96
    (3.7,0.10)
    466
    0.93
    (3.7, 0.09)
    288
    0.90
    (5.0,0.13)
    273
    0.91
    (4.9,0.14)
    235
    0.89
    (5.8,0.15)
    282
    0.87
    (4.7,0.15)
    268
    1.00
    (0.0, 0.00)
    890
    
    
    
    
    
    
    
    M
    0.96
    (3.7,0.10)
    243
    0.92
    (5.0,0.14)
    253
    0.93
    (4.8,0.13)
    245
    0.93
    (5.6,0.14)
    732
    0.90
    (5.3,0.13)
    255
    0.96
    (3.6,0.10)
    437
    0.97
    (3.1,0.09)
    251
    0.94
    (4.0,0.12)
    234
    0.92
    (5.4,0.15)
    215
    0.89
    (6.4,0.17)
    246
    0.95
    (3.7,0.13)
    230
    0.98
    (3.1,0.09)
    672
    1.00
    (0.0, 0.00)
    805
    
    
    
    
    N
    0.95
    (4.5,0.12)
    236
    0.88
    (7.3,0.17)
    238
    0.91
    (6.0, 0.14)
    225
    0.93
    (4.2,0.10)
    540
    0.87
    (7.0,0.18)
    242
    0.95
    (4.5,0.13)
    414
    0.92
    (5.7,0.13)
    235
    0.87
    (5.9,0.17)
    215
    0.90
    (5.2,0.16)
    196
    0.89
    (5.7,0.13)
    237
    0.84
    (6.8, 0.20)
    211
    0.95
    (3.7,0.11)
    512
    0.95
    (4.7,0.14)
    495
    1.00
    (0.0, 0.00)
    596
    
    0
    0.97
    (3.2, 0.08)
    236
    0.89
    (5.9,0.13)
    246
    0.93
    (4.6,0.11)
    237
    0.95
    (4.5,0.11)
    704
    0.89
    (5.7,0.13)
    254
    0.96
    (3.4, 0.09)
    396
    0.96
    (3.5, 0.08)
    240
    0.89
    (4.8,0.13)
    227
    0.92
    (5.1,0.14)
    195
    0.91
    (5.0,0.14)
    231
    0.86
    (4.3,0.13)
    212
    0.97
    (3.4, 0.07)
    630
    0.96
    (3.2, 0.09)
    563
    0.97
    (3.5,0.10)
    447
    1.00
    (0.0, 0.00)
    780
    December 2009                                  A-136
    

    -------
        0.8
        0.6
      o
      13
      o
      O
        0.4
        0.2
                   10       20       30       40       50        60       70
    
                                           Distance Between Samplers (km)
                                                                                80        90       100
    Figure A-66.   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                   Philadelphia, PA.
    December 2009
    A-137
    

    -------
                    Phoenix Core Based  Statistical Area
            A
           01
                        \	| Phoenix CBSA
                          •   PM2.5 Monitors
                        	 Interstate Highways
                           — Major Highways
    
          0 1020   40   60   80  100
                                i Kilometers
    Figure A-67.  PM2.s monitor distribution and major highways, Phoenix, AZ.
    December 2009
    A-138
    

    -------
             Site A
             SiteB
             SiteC
             SiteD
             SiteE
    AQSSitelD
    04-013-0019
    04-013-4003
    04-013-9997
    04-021-0001
    04-021-3002
                              en
                              c
                              o
                              u
                              c
                              o
                              u
                        1=winter
                        2=spring
                        3=summe
                        4=fall
    A B
    Mean 12.3 12.6
    Obs 370 352
    SD 7.6 7.3
    50 -
    40 -
    30 -
    20 -
    10 -
    r 0 -
    
    
    
    
    
    
    
    
    II
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    c
    9.8
    360
    5.5
    
    
    
    
    
    
    
    
    
    
    
    
    
    II
    i
    D E
    8.9 5.9
    227 325
    4.4 2.8
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    1
    \
                                       1234    1234   1234   1234   1234
    Figure A-68.   Box plots illustrating the seasonal distribution of 24-h avg PM2.6 concentrations
                  for Phoenix, AZ.
    December 2009
                               A-139
    

    -------
    Table A-30.    Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
                    Phoenix, AZ.
                    A                     B                    C                      D                      E
          1.00
                                 0.87
                                                       0.92
                                                                            0.50
                                                                                                   0.12
          (0.0,0.00)
    (6.4,0.15)
    (6.5,0.16)
    (10.4,0.25)
    (14.4,0.40)
          370
                                 345
                                                       355
                                                                            222
                                                                                                   321
                                  1.00
                                                       0.89
                                                                            0.54
                                                                                                   0.23
                                  (0.0, 0.00)
                         (6.8,0.17)
                         (9.6, 0.25)
                            (13.2,0.40)
                                 352
                                                       338
                                                                            212
                                                                                                   307
                                                       1.00
                                                                            0.54
                                                                                                   0.18
                                                       (0.0, 0.00)
                                              (7.2, 0.20)
                                                 (9.3,0.33)
                                                       360
                                                                            216
                                                                                                   315
                 LEGEND
                    R
                 (P90, COD)
                    N
                                                                            1.00
                                              (0.0, 0.00)
                                              227
                                                                                                   0.51
                                                 (7.8, 0.27)
                                                                      200
                                                                                                    1.00
                                                                                                    (0.0, 0.00)
                                                                                                   325
    December 2009
                               A-140
    

    -------
        0.8
        0.6
      o
      o
        0.4
        0.2
                   10       20       30
                                             40       50       60
    
    
                                           Distance Between Samplers (km)
                                                                       70       80       90       100
    Figure A-69.   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                   Phoenix, AZ.
    December 2009
    A-141
    

    -------
           01
              r
                    Pittsburgh Combined Statistical Area
                            0   10   20
      40
    60
                             Pittsburgh CSA
                          •   PM2.5 Monitors
                          	 Interstate Highways
                             Major Highways
    80
     100
    —i Kilometers
    Figure A-70.  PM2.s monitor distribution and major highways, Pittsburgh, PA.
    December 2009
    A-142
    

    -------
    Mean 15.1 19.8 13.2 13.6 15.1 16.4
    Obs 1063 1066 306 165 332 337
    SD 8.9 14.7 8.0 8.5 9.0 9.5
    70-
    AQSSitelD
    Site A 42-003-0008
    SteB 42-003-0054 60~
    SiteC 42-003-0067
    SiteD 42-003-0095 ~ 50_
    SiteE 42-003-1008 -t
    SiteF 42-003-1301 3
    C 40 -
    g
    Ł
    OJ
    u
    c.
    o
    u
    20-
    1 0 -
    1 -winter
    2=spring
    3=summer
    4=fall 0 -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    II
    
    
    1
    
    
    234 234 234 1234 1234 1234
    G H J K L
    Mean 15.3 16.4 15.5 14.8 13.4 15.4
    Ofcs 171 328 354 345 966 350
    SD 8.3 9.3 8.6 8.0 8.6 8.7
    70 -
    AQS Site ID
    SiteG 42-003-3007
    SiteH 42-007-0014 60 "
    Site! 42-125-0005
    SiteJ 42-125-0200 ~ 5Q_
    SiteK 42-125-5001 -5
    en
    SiteL 42-129-0008 3
    c 40-
    O
    c 30-
    OJ
    u
    c
    0
    u
    20-
    1 =winter
    2=spring
    3=summer
    4=fall o -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                          1234  1234  1234  1234  1234
    Figure A-71.   Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                  for Pitsburgh, PA.
    December 2009
    A-143
    

    -------
     Table A-31.     Inter-sampler correlation  statistics for each pair of PM2 5 monitors reporting to AQS for
    
                           Pittsburgh,  PA.
    
    
             ABCDEFGH             I             JKL
     A      1.00	079	0.95	0.92	0.93	0.95	0.95	0.85	0.90	0.93	0.91	0.88
          (0.0,0.00)     (15.9,0.19)      (5.6,0.13)       (47,0.11)      (47,0.11)       (4.9,0.10)      (3.8,0.10)      (6.4,0.13)      (6.4,0.13)      (5.0,0.12)      (6.0,0.13)       (5.6,0.12)
    	1063	1035	298	164	323	329	170	319	344	337	934	340
    _B	UK)	071	0.65	0.80	0.85	076	0.69	071	0.68	0.68	0.67
                                    (16.9,0.24)     (17.4,0.25)      (14.4,0.19)     (12.5,0.14)     (157,0.20)     (17.0,0.19)     (157,0.21)      (17.8,0.23)     (19.3,0.25)     (15.9,0.21)
                                       303	165	329	335	171	324	350	341	938	346
                                       1.00	0.93	0.90	0.91	0.94	0.80	0.93	0.96	0.95	0.91
                                     (0.0,0.00)       (2.8,0.09)      (6.6,0.16)       (87,0.17)      (6.0,0.14)      (9.4,0.19)      (67,0.15)      (4.6,0.12)      (4.5,0.10)       (6.5,0.15)
                                       306	144	282	282	148	268	290	286	270	286
                                   	100	0.84	0.87	0.91	0.79	0.89	0.91	0.97	0.85
                                   	(0.0,0.00)      (6.4,0.15)       (8.5,0.16)      (5.8,0.13)      (9.2,0.17)      (5.9,0.13)      (4.6,0.11)      (3.1,0.08)       (6.5,0.15)
                                   	165	153	161	158	156	158	155	146	157
                                   	yra	0.90	0.90	OJH	0.55	g.86	g.88	o.83
                                                                              (6.4,0.13)      (6.5,0.13)      (6.8,0.14)      (8.3,0.16)
                             LEGEND        	332	313	157	295	320	315	290	318
                            Pearson R       	1.00	OJM	0.82	0.88	0.88	0.89	0.86
                                               	(0.0,0.00)      (67,0.13)      (7.4,0.14)      (7.1,0.15)      (7.9,0.15)      (8.8,0.17)      (7.0,0.14)
                                               	337	167	302	327	319	296	322
                                           	100	0.78	0.94	0.93	0.90	0.91
                                           	(0.0,0.00)      (7.3,0.16)      (4.0,0.10)      (5.0,0.11)      (6.6,0.15)      (5.0,0.13)
                                           	171	159	163	159	149	161
                                           	yra	0.80	g78	0.82	0.70
                                           	(0.0,0.00)      (8.4,0.15)      (8.2,0.17)      (9.0,0.18)      (9.2,0.18)
                                           	328	317	3JK	288	314
                                                                                                                         1.00           0.93           0.89           0.88
                                                                                                                         354           334           310           339
                                                                                                                                      1.00	0.93
                                                                                                                                                  (5.5,0.12)      (5.9,0.13)
                                                                                                                                      345           302           331
                                                                                                                                                                 0.86
                                                                                                                                                  (0.0,0.00)      (6.9,0.15)
                                                                                                                                                    966           306
                                                                                                                                                               (0.0, 0.00)
                                                                                                                                                                  350
     December  2009                                                          A-144
    

    -------
                      *    •  **  *  •
                       •   • -     »*  •  •
                       *     *     **«»
           0.8 -
           0.6 -
         o
         1
         g
         5
           0.4 -
           0.2 -
                     10      20       30
                                              40       50      60       70
    
                                            Distance Between Samplers (km)
                                                                               80       90      100
    Figure A-72.   PM2.s inter-sampler correlations as a function of distance between monitors for
                   Pittsburgh, PA.
    December 2009
    A-145
    

    -------
                    Riverside Core Based Statistical Area
            A
           01
                        \	| Riverside CBSA
                          •  PM2.5 Monitors
                        	 Interstate Highways
                            — Major Highways
    
            0 1020  40  60  80  100
                               i Kilometers
    Figure A-73.   PM2.s monitor distribution and major highways, Riverside, CA.
    December 2009
    A-146
    

    -------
     Site A
     SiteB
     SiteC
     SiteD
     SiteE
     SiteF
     SiteG
    AQS Site ID
    06-065-1003
    06-065-2002
    06-065-8001
    06-071-0025
    06-071-0306
    06-071-2002
    06-071-9004
                     en
                     c
                     o
                     4->
                     TO
                     •>->
                     C.
                     OJ
                     u
                     c
                     o
                     u
               1 = winter
               2=spring
               3=summer   g
               4=fall
    A B
    Mean 17.7 9.9
    Obs 314 310
    SD 11.6 4.9
    70 -
    60 -
    50 -
    40 -
    30 -
    20 -
    10 -
    0 -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I*
    
    C D E
    19.7 18.4 9.9
    934 319 236
    12.7 10.9 4.4
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    IPI
    
    F G
    18.4 17.7
    328 310
    11.9 12.2
    
    
    
    
    
    
    '
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                1234   1234   1234   1234   1234   1234  1234
    Figure A-74.   Box plots illustrating the seasonal distribution of 24-h avg PM2.6 concentrations
                  for Riverside, CA.
    December 2009
                                       A-147
    

    -------
    Table A-32.   Inter-sampler correlation statistics for each pair of PM2.6 monitors reporting to AQS for
                 Riverside, CA.
    ABC
    A 1.00 0.45 0.96
    (0.0,0.00) (20.6,0.32) (5.0,0.10)
    314 269 297
    B 1.00 0.49
    (0.0, 0.00) (22.7, 0.35)
    310 289
    C 1.00
    (0.0, 0.00)
    934
    D
    
    LEGEND
    E R
    (P90, COD)
    N
    F
    
    
    G
    D
    0.92
    (7.2,0.13)
    282
    0.49
    (20.9, 0.34)
    270
    0.91
    (8.2,0.14)
    300
    1.00
    (0.0, 0.00)
    319
    
    
    
    
    
    
    
    E
    0.36
    (22.1,0.35)
    191
    0.42
    (8.2, 0.25)
    203
    0.37
    (26.6, 0.37)
    227
    0.36
    (20.1,0.35)
    195
    1.00
    (0.0, 0.00)
    236
    
    
    
    
    F
    0.94
    (6.0,0.12)
    281
    0.49
    (19.7,0.33)
    285
    0.92
    (6.9,0.12)
    302
    0.93
    (6.7,0.14)
    289
    0.40
    (21.1,0.36)
    201
    1.00
    (0.0, 0.00)
    328
    
    G
    0.90
    (5.7,0.13)
    273
    0.50
    (18.8,0.31)
    266
    0.91
    (7.6,0.12)
    287
    0.82
    (9.6,0.17)
    274
    0.41
    (21.6,0.34)
    190
    0.90
    (6.7,0.12)
    276
    1.00
    (0.0, 0.00)
    310
    December 2009                                  A-148
    

    -------
        1.2
        0.8
        0.6
      o
      o
        0.4
        0.2
                          * «»   *
                   10       20       30       40       50       60       70
    
    
                                           Distance Between Samplers (km)
                                                                                80        90       100
    Figure A-75.   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                   Riverside CA.
    December 2009
    A-149
    

    -------
                      Seattle Combined Statistical Area
           01
              r
                          \ Seattle CSA
                        •   PM2.5 Monitors
                       	 Interstate Highways
                         — Major Highways
                                              0  10 20   40   60   80
                               100
                              —i Kilometers
    Figure A-76.  PM2.s monitor distribution and major highways, Seattle, WA.
    December 2009
    A-150
    

    -------
                         AQS Site ID
                Site A    53-033-0024
                Site B    53-053-0029
                SiteC    53-061-1007
                                         c
                                         o
                                         ro
                                         c
                                         Ol
                                         u
                                         c
                                         o
                                         u
    1=winter
    2=spring
    3=surr
    4=fall
    ABC
    Mean 8.9 10.2 9.2
    Obs 352 354 591
    SD 7.3 10.1 7.9
    60 -
    50 -
    40 -
    30 -
    10 -
    ;r 0 -
    
    
    
    
    
    
    ll
    
    
    
    
    
    
    
    
    
    
    
    ll
    
    
    
    
    
    
    
    
    
    
    I
    
                                                  1234   1234    1234
    Figure A-77.   Box plots illustrating the seasonal distribution of 24-h avg PM2.s concentrations
                  for Seattle, WA.
    December 2009
               A-151
    

    -------
    Table A-33.   Inter-sampler correlation statistics for each pair of PM2 5 monitors reporting to AQS for
                  Seattle, WA.
                                               1.00
                                                          0.89
                                               352
                                     LEGEND
                                       R
                                    (P90, COD)
                                       N
                                                          337
                                                          1.00
         354
                                                                      0.86
                                               (0.0,0.00)     (6.3,0.16)     (4.5,0.14)
                                                                      331
                                                                      0.80
         (0.0, 0.00)    (7.8, 0.20)
                    335
                                                                      1.00
                                                                      (0.0, 0.00)
                                                                      591
         0.8
         0.6
       o
       13
       o
       O
         0.4
         0.2
                    10       20        30        40        50       60       70
                                              Distance Between Samplers (km)
                                                                                     80
                                                                                              90
                                                                                                       100
    Figure A-78.   PM2.s inter-sampler correlations as a function of distance between monitors for
                    Seattle, WA.
    December 2009
    A-152
    

    -------
                     St. Louis Combined  Statistical Area
           01
              r
                        St. Louis CSA
                    •   PM2.5 Monitors
                    	 Interstate Highways
                      — Major Highways
                                      0  10  20     40    60    80
                              100
                             —i Kilometers
    Figure A-79.  PM2.s monitor distribution and major highways, St. Louis, MO.
    December 2009
    A-153
    

    -------
    AQSSitelD A B C D E F
    Site A 17-083-1001 Megn 132 16g R6 144 158 142
    SiteB 17-119-1007
    SiteC 17-119-2009 Obs 173 329 163 349 166 349
    SiteD 17-119-3007 SD 7.9 8.2 7.7 7.5 7.6 7.1
    SiteE 17-163-0010 50-
    SiteF 17-163-4001
    40 -
    li
    1 30-
    c
    o
    ro
    I 2°-
    — ' \ i
    ° III
    10 -
    1=winter
    2=spring
    3=summer 0 -
    
    
    
    
    
    
    
    
    
    
    
    
    4=fall 1234 1234 1234 1234 1234 1234
    AQSSitelD G H J K L
    SiteG 29-099-0012 Mean 13g 132 135 144 144 146
    SiteH 29-183-1002
    Site I 29-189-2003 °bs 104° 566 619 1049 1038 1046
    SiteJ 29-510-0007 SD 7.4 7.4 7.3 7.3 7.5 7.5
    SiteK 29-510-0085 50 -
    SiteL 29-510-0087
    40 -
    ^
    cn
    5 30 -
    c
    0
    TO
    C
    
    -------
    Table A-34.
    Site A
    A 1.00
    (0.0,0.00)
    173
    B
    
    
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    
    
    J
    
    
    K
    
    
    L
    
    Inter-sampler correlation statistics for each pair
    St. Louis, MO.
    B C D E F
    0.85 0.93 0.89 0.88 0.86
    (10.5,0.23) (4.7,0.17) (5.0,0.17) (7.3,0.20) (6.2,0.18)
    156 129 162 146 156
    1.00 0.89 0.86 0.85 0.82
    (0.0,0.00) (8.6,0.16) (7.4,0.16) (7.7,0.16) (8.6,0.17)
    329 135 301 156 306
    1.00 0.94 0.91 0.88
    (0.0,0.00) (4.0,0.11) (6.4,0.13) (5.7,0.13)
    163 139 124 133
    1.00 0.89 0.84
    (0.0,0.00) (5.7,0.13) (6.0,0.15)
    349 156 314
    1.00 0.90
    (0.0,0.00) (5.5,0.12)
    166 152
    1.00
    (0.0,0.00)
    LEGEND 349
    R
    (P90, COD)
    N
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    G
    0.85
    (4.8,0.17)
    167
    0.88
    (7.8,0.17)
    312
    0.90
    (5.5,0.13)
    158
    0.89
    (4.9,0.12)
    331
    0.91
    (6.2,0.13)
    159
    0.89
    (5.4,0.12)
    333
    1.00
    (0.0, 0.00)
    1040
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Of PM2.6
    H
    0.93
    (4.1,0.13)
    158
    0.89
    (8.2,0.18)
    305
    0.96
    (3.9,0.11)
    141
    0.94
    (4.3,0.12)
    315
    0.90
    (5.8,0.16)
    153
    0.86
    (6.1,0.16)
    317
    0.93
    (4.3,0.10)
    533
    1.00
    (0.0, 0.00)
    566
    
    
    
    
    
    
    
    
    
    
    
    monitors reporting to AQS for
    i
    0.86
    (4.4,0.16)
    162
    0.88
    (7.9,0.17)
    318
    0.94
    (5.3,0.11)
    144
    0.92
    (4.5,0.11)
    326
    0.91
    (5.3,0.14)
    157
    0.88
    (5.4,0.13)
    332
    0.94
    (3.3, 0.08)
    586
    0.96
    (3.0, 0.08)
    550
    1.00
    (0.0, 0.00)
    619
    
    
    
    
    
    
    
    
    J
    0.84
    (6.0,0.18)
    168
    0.86
    (7.7,0.17)
    316
    0.90
    (5.7,0.13)
    158
    0.89
    (4.7,0.13)
    335
    0.93
    (5.1,0.13)
    160
    0.88
    (5.3,0.14)
    337
    0.96
    (2.9, 0.08)
    994
    0.95
    (4.1,0.12)
    552
    0.96
    (3.1,0.09)
    605
    1.00
    (0.0, 0.00)
    1049
    
    
    
    
    
    K
    0.84
    (5.7,0.19)
    169
    0.87
    (7.5,0.16)
    316
    0.89
    (5.6,0.14)
    160
    0.88
    (4.6,0.12)
    332
    0.91
    (4.9,0.13)
    163
    0.85
    (5.6,0.14)
    332
    0.93
    (3.9,0.10)
    987
    0.95
    (3.8,0.12)
    546
    0.95
    (3.1,0.10)
    599
    0.96
    (2.5, 0.09)
    1001
    1.00
    (0.0, 0.00)
    1038
    
    
    
    0.88
    (5.3,
    166
    0.89
    (6.8,
    315
    0.94
    (4.4,
    156
    0.92
    (3.9,
    336
    0.95
    (3.7,
    160
    0.88
    (5.4,
    334
    0.94
    (3.8,
    992
    0.96
    (4.0,
    544
    0.96
    (3.4,
    598
    0.97
    (2.5,
    1007
    0.97
    (1.9,
    991
    1.00
    (0.0,
    L
    
    0,
    
    
    0,
    
    
    0,
    
    
    o.
    
    
    0,
    
    
    0,
    
    
    0,
    
    
    0,
    
    
    
    
    .17)
    
    
    .14)
    
    
    .11)
    
    
    .11)
    
    
    .10)
    
    
    .13)
    
    
    .10)
    
    
    .11)
    
    
    0.09)
    
    
    
    
    0.08)
    
    
    
    
    0.07)
    
    
    
    
    0.00)
    1046
    December 2009                                      A-155
    

    -------
                 *••*..>
                                           •  ».     •«*.
                                           «.   *  •  **
              0.2
                0      10      20      30
                                            40      50      60      70
    
    
                                           Distance Between Samplers (km)
                                                                                90     100
    Figure A-81   PM2.s inter-sampler correlations as a function of distance between monitors for
    
                  St. Louis, MO.
    December 2009
    A-156
    

    -------
                      Atlanta Combined Statistical Area
                                                                 Atlanta CSA
                                                              •   PMio Monitors
                                                                 Interstate Highways
                                                                 Major Highways
    
                                                                      100
                                                                        Kilometers
    Figure A-82.  PM™ monitor distribution and major highways, Atlanta, GA.
    December 2009
    A-157
    

    -------
          Site A
          SiteB
          SiteC
          SiteD
          SiteE
          SiteF
     AQS Site ID
    13-089-2001
    13-097-0003
    13-121-0001
    13-121-0032
    13-121-0048
    13-255-0002
    ID Mean 24.7
    31 Obs 172
    33 SD
    31 70 -
    32
    18
    32 60 -
    ^ 50 -
    en
    c 40 -
    0
    4-*
    ro
    c 30 -
    CD
    U
    O
    U 20 -
    10 -
    1=winter
    2=spring
    3=summer^ "
    4=fall
    13.0
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    1234 '
    B C D E
    21.4 23.4 26.6 25.0
    178 171 174 995
    9.3 9.5 11.8 11.5
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    234 1234 1234 1234
    F
    21.6
    178
    9.7
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    1234
    Figure A-83.   Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations
                  for Atlanta, GA.
    December 2009
                                    A-158
    

    -------
    Table A-35.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                    Atlanta, GA.
      Site
             1.00
                                0.69
                                                   0.74
                                                                      0.78
                                                                                         0.70
                                                                                                            0.59
             (0.0,0.00)
    (18.0,0.22)
    (15.0,0.20)
    (13.0,0.20)
    (16.0,0.22)
    (20.0, 0.24)
             172
                                169
                                                   162
                                                                      165
                                                                                         158
                                                                                                            164
                                1.00
                                                   0.88
                                                                      0.79
                                                                                         0.71
                                                                                                            0.82
                                (0.0, 0.00)
                       (6.0,0.12)
                       (14.5,0.17)
                       (16.0,0.18)
                       (10.0,0.14)
                                178
                                                   167
                                                                      170
                                                                                         162
                                                                                                            169
                                                   1.00
                                                                      0.88
                                                                                         0.84
                                                                                                           0.82
                                                   (0.0, 0.00)
                                          (9.0,0.13)
                                          (10.0,0.13)
                                          (9.0,0.15)
                                                   171
                                                                      162
                                                                                         155
                                                                                                            161
                  LEGEND
                     R
                 (P90, COD)
                     N
                                                                      1.00
                                                                                         0.75
                                          (0.0,0.00)
                                          (12.0,0.15)
                                          174
                                                             158
                                                                                         1.00
                                                                                                            0.74
                                          (15.0,0.20)
                                                                               166
                                                                                                           0.67
                                                                                         (0.0,0.00)
                                                                               (17.0,0.19)
                                                                                         995
                                                                                                            163
                                                                                                            1.00
                                                                                                            (0.0, 0.00)
                                                                                                            178
    December 2009
                                  A-159
    

    -------
        0.8
        0.6
      o
      o
        0.4
        0.2
                   10       20       30
                                             40       50       60
    
    
                                           Distance Between Samplers (km)
                                                                      70       80       90       100
    Figure A-84.   PM™ inter-sampler correlations as a function of distance between monitors for
    
                   Atlanta, GA.
    December 2009
    A-160
    

    -------
                  Birmingham Combined Statistical Area
            A
          01
                            Birmingham CSA
                         •   PMio Monitors
                         	 Interstate Highways
                          — Major Highways
                                   0  10 20     40     60     80
                              100
                              —i Kilometers
    Figure A-85.   PM™ monitor distribution and major highways, Birmingham, AL.
    December 2009
    A-161
    

    -------
                AQS Site ID
          SiteA 01-073-0002
          SiteB 01-073-0023
          SiteC 01-073-0034
          SiteD 01-073-1003
          SiteE 01-073-1008
          SiteF 01-073-1010
          SiteG 01-073-2003
          SiteH 01-073-6002
          Site I  01-073-6003
          SiteJ 01-073-6004
                       c
                       O
    concen
                 1=winter
                 2=spring
                 3=summer
                 4=fall
    A B C D E F
    Mean 29.1 32.9 26.5 27.1 27.6 24.7
    Obs 180 1095 224 183 179 179
    3D 12.6 20.0 11.4 11.8 14.3 11.0
    150 -
    140 -
    130 -
    120 -
    110 -
    100 -
    90 -
    80 -
    60 -
    50 -
    40 -
    30 -
    20 -
    0 -
    
    
    
    
    
    
    
    
    
    III
    
    I
    H
    i
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    i
    
    i
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    il
    i il I
    T
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    ll
    i
    "
    
    i
    G H J
    26.0 28.8 38.0 48.2
    1090 181 1087 1080
    14.0 12.6 29.5 30.0
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    \
    
    
    
    
    
    
    
    
    
    
    
    I
    '
    
    
    
    
    
    
    
    
    
    
    
    
    1
    1
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                1234  1234  1234   1234  1234  1234  1234  1234  1234  1234
    Figure A-86.   Box plots illustrating the seasonal distribution of 24-h avg PMio concentrations
                     for Birmingham, AL
    December 2009
    A-162
    

    -------
    Table A-36. Inter-sampler correlation statistics for each pair
    Birmingham, AL
    ABC
    A 1.00 0.80 0.88
    (0.0,0.00) (23.0,0.16) (11.0,0.11)
    180 180 174
    B 1.00 0.82
    (0.0,0.00) (23.0,0.17)
    1095 224
    C 1.00
    (0.0, 0.00)
    224
    D
    
    
    E
    
    
    F
    LEGEND
    R
    G (P90, COD)
    N
    
    H
    
    
    I
    
    
    J
    D E F
    0.86 0.78 0.84
    (12.0,0.13) (12.0,0.14) (13.0,0.13)
    180 176 171
    0.74 0.61 0.73
    (25.0,0.21) (26.0,0.20) (26.0,0.19)
    183 179 179
    0.84 0.66 0.78
    (10.0,0.12) (15.0,0.16) (12.0,0.14)
    175 171 168
    1.00 0.67 0.79
    (0.0,0.00) (15.0,0.17) (12.0,0.15)
    183 178 173
    1.00 0.67
    (0.0,0.00) (16.0,0.15)
    179 169
    1.00
    (0.0, 0.00)
    179
    
    
    
    
    
    
    
    
    
    
    of PMio monitors reporting to AQS for
    G
    0.77
    (15.0,0.18)
    180
    0.75
    (25.0, 0.20)
    1090
    0.74
    (14.0,0.17)
    224
    0.76
    (14.0,0.17)
    183
    0.64
    (18.0,0.18)
    179
    0.75
    (14.0,0.16)
    179
    1.00
    (0.0, 0.00)
    1090
    
    
    
    
    
    
    
    H
    0.78
    (14.0,0.15)
    178
    0.71
    (25.0, 0.22)
    181
    0.80
    (13.0,0.15)
    173
    0.84
    (11.0,0.12)
    180
    0.56
    (19.0,0.20)
    176
    0.74
    (15.0,0.17)
    171
    0.76
    (15.0,0.19)
    181
    1.00
    (0.0, 0.00)
    181
    
    
    
    
    I
    0.41
    (41.0,0.30)
    179
    0.26
    (51.0,0.33)
    1087
    0.33
    (43.0, 0.32)
    222
    0.45
    (42.0, 0.30)
    182
    0.33
    (45.0, 0.32)
    178
    0.36
    (43.0, 0.32)
    178
    0.59
    (43.0, 0.27)
    1083
    0.58
    (38.0, 0.27)
    180
    1.00
    (0.0, 0.00)
    1087
    
    J
    0.29
    (68.0, 0.34)
    177
    0.23
    (57.0, 0.36)
    1080
    0.41
    (62.0, 0.34)
    221
    0.41
    (65.5, 0.34)
    180
    0.12
    (71.0,0.39)
    176
    0.21
    (71.0,0.38)
    177
    0.15
    (63.0, 0.39)
    1075
    0.50
    (59.0,0.31)
    178
    0.05
    (72.0, 0.40)
    1072
    1.00
    (0.0, 0.00)
    1080
    December 2009                                      A-163
    

    -------
        0.8
        0.6
                *   •          * *
            *       1   «
      o
      o
        0.4
        0.2
                   10       20       30
                                            40       50       60
    
    
                                          Distance Between Samplers (km)
                                                                     70       80       90      100
    Figure A-87   PM™ inter-sampler correlations as a function of distance between monitors for
    
                  Birmingham, AL
    December 2009
    A-164
    

    -------
                      Boston  Combined Statistical Area
            A
          01
                            Boston CSA
                         •  PMio Monitors
                         	 Interstate Highways
                            Major Highways
                                         0 10 20    40    60    80
                               100
                              ^Kilometers
    Figure A-88.  PM™ monitor distribution and major highways, Boston, MA.
    December 2009
    A-165
    

    -------
    
    Site A
    SiteB
    SiteC
    SiteD
    SiteE
    SiteF
    SiteG
    SiteH
    AQS Site ID
    25-025-0042
    25-027-0023
    33-01 1-0020
    33-015-0014
    44-003-0002
    44-007-0022
    44-007-0026
    44-007-0027
                      1 =winter
                      2=spring
                      3=summer
                      4=fall
    ABCDEFGH
    Mean 16.4 21.6 16.5 14.8 10.7 17.0 21.3 18.8
    Ote 191 174 182 175 171 182 169 168
    SD
    60 -
    50-
    -I 40-
    Ol
    3.
    C
    O
    tXJ
    concent
    0
    1
    10 -
    o -
    7.7 11.9 9.2 8.2 7.0 8.7 10.8 9.4
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    \ [
    
    \
    
    
    
    
    
    
    
    
                                      1234  1234  12341234  1234  1234  1234  1234
    Figure A-89.   Box plots illustrating the seasonal distribution of 24-h avg PMi0 concentrations
                   for Boston, MA.
    Table A-37.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                 Boston, MA.
    Site A B
    A 1.00 0.69
    (0.0,0.00) (15.0,0.22)
    191 169
    B 1.00
    (0.0, 0.00)
    174
    C
    
    
    D
    
    LEGEND
    
    /pqn (*oru
    
    F n
    
    
    G
    
    C
    0.69
    (12.0,0.20)
    179
    0.66
    (17.0,0.24)
    167
    1.00
    (0.0, 0.00)
    182
    
    
    
    
    
    
    
    
    
    
    
    D
    0.73
    (10.0,0.22)
    173
    0.56
    (19.0,0.28)
    161
    0.72
    (10.0,0.22)
    170
    1.00
    (0.0, 0.00)
    175
    
    
    
    
    
    
    
    
    E
    0.71
    (13.0,0.30)
    171
    0.45
    (24.0, 0.39)
    158
    0.47
    (17.0,0.33)
    168
    0.63
    (11.0,0.29)
    163
    1.00
    (0.0, 0.00)
    171
    
    
    
    
    
    F
    0.84
    (8.0,0.14)
    182
    0.69
    (15.0,0.21)
    169
    0.62
    (12.0,0.21)
    179
    0.68
    (10.0,0.23)
    173
    0.84
    (13.0,0.29)
    171
    1.00
    (0.0, 0.00)
    182
    
    
    G
    0.70
    (15.0,0.20)
    169
    0.77
    (12.0,0.17)
    156
    0.64
    (16.0,0.26)
    166
    0.59
    (19.0,0.30)
    161
    0.58
    (22.0, 0.38)
    161
    0.81
    (11.0,0.16)
    169
    1.00
    (0.0, 0.00)
    H
    0.79
    (10.0,0.17)
    167
    0.65
    (16.0,0.20)
    154
    0.59
    (16.0,0.24)
    164
    0.69
    (13.0,0.26)
    158
    0.80
    (15.0,0.33)
    157
    0.95
    (5.0,0.11)
    167
    0.79
    (10.0,0.13)
    169 154
    H
    
    
    
    
    
    1.00
    (0.0, 0.00)
    168
    December 2009
    A-166
    

    -------
        0.8
        0.6
      o
      u
        0.4 -
        0.2
                   10       20       30       40       50       60       70
    
    
                                           Distance Between Samplers (km)
                                                                                      90       100
    Figure A-90    PM™ inter-sampler correlations as a function of distance between monitors for
    
                   Boston, MA.
    December 2009
    A-167
    

    -------
                     Chicago Combined  Statistical Area
          01
             r
                           J Chicago CSA
                         •  PMio Monitors
                         	 Interstate Highways
                            Major Highways
                                        0 10 20    40    60    80
                               100
                              —i Kilometers
    Figure A-91.   PM™ monitor distribution and major highways, Chicago, IL.
    December 2009
    A-168
    

    -------
                      Site A
                      SiteB
                      SteC
                      SiteD
                      SiteE
                      SiteF
                      SteG
                      SiteH
    Site ID ABCDEFGH
    1-0001 Mean 22.4 24.7 30.4 32.4 24.5 27.2 26,9 21.6
    1-0022 Obs 179 1077 176 1058 174 176 174 176
    1-0060 3D
    1-1016 8° -
    1-1901
    1-2001 ?0 _
    1 iini
    I -OoU I
    7-1002
    60 -
    -- 50 -
    CTi
    a.
    O 40 -
    m
    ai 30 -
    u
    c
    o
    u 20 -
    10 -
    1 -winter
    2=spring _
    3=summer
    4=fall
    10.9 13.1 15.1 173 11.9 13.4 12,3 12.3
    
    
    
    
    
    
    
    
    
    
    
    
    
    1234 1234 12341234
    
    
    
    
    
    
    
    
    
    
    
    
    
    1234 1234 1234 234
                            AQSSitelD
                      Site I  18-089-0006
                      SiteJ  18-089-0022
                      SiteK  18-089-0023
                      SiteL  18-089-2010
                      SiteM 18-127-0022
                      SiteN  18-127-0023
                      SiteO 18-127-0024
                              1 =winter
                              2=spring
                              3=sum
                              4=fall
    ID J K L M N 0
    06 Mean 28.2 27.9 26.4 16.6 17.2 24.1 18.3
    22 Obs 182 1059 172 169 173 1051 169
    SD 13.8 18.1 9.5 9.8 11.2 15.1 10.7
    10 8°-
    22
    23 70-
    24
    " 60 -
    _E
    en
    3 50-
    c
    o
    H 40 -
    c
    a;
    u
    c 30 -
    o
    u
    20 -
    10 -
    ter
    ng
    mer o -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                          1234  1234  1234   1234  1234  1234  1234
    Figure A-92.    Box plots illustrating the seasonal distribution of 24-h avg PMi0 concentrations
                     for Chicago, IL
    December 2009
    A-169
    

    -------
    Table A-38.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                 Chicago, IL.
    Site A B
    A 1.00 0.78
    (0.0,0.00) (15.0,0.18)
    179 176
    B 1.00
    (0.0, 0.00)
    1077
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    
    
    J
    
    
    K
    
    
    L
    
    
    M
    
    
    N
    
    
    0
    C
    0.68
    (23.0, 0.24)
    173
    0.66
    (23.0, 0.23)
    173
    1.00
    (0.0, 0.00)
    176
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    LEGEND
    R
    (P90, COD)
    N
    
    
    
    
    
    
    
    
    
    
    
    
    
    D E
    0.83 0.93
    (25.0,0.22) (8.0,0.10)
    174 171
    0.74 0.76
    (23.0,0.21) (14.0,0.17)
    1040 171
    0.63 0.72
    (26.0,0.23) (21.0,0.21)
    171 169
    1.00 0.79
    (0.0,0.00) (27.0,0.21)
    1058 169
    1.00
    (0.0, 0.00)
    174
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    F
    0.92
    (11.0,0.13)
    173
    0.84
    (12.0,0.15)
    173
    0.74
    (18.5,0.19)
    170
    0.85
    (19.0,0.17)
    171
    0.93
    (9.0,0.10)
    168
    1.00
    (0.0, 0.00)
    176
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    G
    0.86
    (12.0,0.17)
    171
    0.79
    (13.0,0.18)
    171
    0.64
    (19.0,0.21)
    168
    0.79
    (23.0,0.19)
    169
    0.84
    (13.0,0.16)
    166
    0.84
    (12.0,0.15)
    169
    1.00
    (0.0, 0.00)
    174
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    H
    0.79
    (12.0,0.18)
    167
    0.74
    (17.0,0.23)
    173
    0.62
    (22.0, 0.27)
    164
    0.74
    (27.0, 0.28)
    171
    0.86
    (10.0,0.16)
    163
    0.86
    (13.0,0.19)
    165
    0.77
    (15.0,0.22)
    162
    1.00
    (0.0, 0.00)
    176
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    0.75
    (13.0,0.18)
    179
    0.68
    (16.0,0.19)
    179
    0.62
    (23.0, 0.20)
    176
    0.70
    (20.0,0.19)
    177
    0.74
    (13.0,0.16)
    174
    0.77
    (12.0,0.14)
    176
    0.69
    (14.0,0.18)
    174
    0.71
    (16.0,0.23)
    170
    1.00
    (0.0, 0.00)
    182
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    J
    0.14
    (22.0, 0.28)
    173
    0.36
    (22.0, 0.24)
    1041
    0.19
    (26.5, 0.28)
    170
    0.23
    (32.0, 0.29)
    1022
    0.17
    (22.0, 0.26)
    168
    0.21
    (23.0, 0.25)
    170
    0.28
    (23.0, 0.26)
    168
    0.18
    (27.0, 0.30)
    169
    0.24
    (22.0, 0.24)
    176
    1.00
    (0.0, 0.00)
    1059
    
    
    
    
    
    
    
    
    
    
    
    
    
    K
    0.69
    (15.0,0.21)
    169
    0.73
    (16.0,0.19)
    169
    0.49
    (24.0, 0.23)
    166
    0.69
    (24.0, 0.23)
    168
    0.70
    (15.0,0.19)
    164
    0.75
    (16.0,0.17)
    166
    0.74
    (14.0,0.18)
    165
    0.66
    (18.0,0.25)
    161
    0.69
    (12.0,0.15)
    172
    0.49
    (15.0,0.20)
    166
    1.00
    (0.0, 0.00)
    172
    
    
    
    
    
    
    
    
    
    
    L
    0.89
    (13.0,0.22)
    166
    0.81
    (18.0,0.27)
    166
    0.66
    (29.0, 0.37)
    163
    0.82
    (31.0,0.36)
    166
    0.89
    (15.0,0.25)
    161
    0.89
    (18.0,0.28)
    163
    0.86
    (19.0,0.31)
    161
    0.83
    (13.0,0.23)
    157
    0.75
    (20.0, 0.32)
    169
    0.38
    (25.0, 0.34)
    163
    0.80
    (17.0,0.32)
    161
    1.00
    (0.0, 0.00)
    169
    
    
    
    
    
    
    
    M
    0.55
    (21.0,0.30)
    170
    0.66
    (23.0,0.31)
    170
    0.39
    (33.0, 0.40)
    167
    0.61
    (36.0, 0.39)
    168
    0.53
    (22.0, 0.33)
    166
    0.62
    (25.0, 0.34)
    167
    0.52
    (24.0, 0.36)
    165
    0.59
    (19.0,0.29)
    161
    0.50
    (26.0, 0.37)
    173
    0.22
    (28.0, 0.36)
    168
    0.54
    (24.0, 0.35)
    165
    0.60
    (15.0,0.26)
    161
    1.00
    (0.0, 0.00)
    173
    
    
    
    
    N
    0.27
    (16.0,0.24)
    171
    0.33
    (19.0,0.25)
    1033
    0.27
    (26.0, 0.26)
    168
    0.29
    (31.0,0.29)
    1020
    0.34
    (17.0,0.22)
    166
    0.32
    (20.0, 0.23)
    168
    0.33
    (19.0,0.24)
    166
    0.36
    (17.0,0.25)
    168
    0.39
    (16.0,0.21)
    174
    0.48
    (22.0,0.21)
    1018
    0.49
    (14.0,0.19)
    164
    0.33
    (19.0,0.31)
    161
    0.24
    (21.0,0.35)
    165
    1.00
    (0.0, 0.00)
    1051
    
    0
    0.75
    (15.0,0.23)
    166
    0.77
    (20.0, 0.26)
    166
    0.61
    (31.0,0.35)
    163
    0.76
    (31.0,0.33)
    164
    0.73
    (18.0,0.25)
    163
    0.80
    (20.0, 0.27)
    163
    0.70
    (22.0, 0.30)
    163
    0.76
    (14.0,0.22)
    157
    0.68
    (21.0,0.30)
    169
    0.22
    (27.0, 0.33)
    164
    0.65
    (21.0,0.31)
    162
    0.78
    (10.0,0.20)
    158
    0.84
    (8.0,0.16)
    161
    0.31
    (19.0,0.29)
    161
    1.00
    (0.0, 0.00)
    169
    December 2009                                   A-170
    

    -------
        0.8
        0.6
               « «
    
                             *      *       •
                             *»*  »    »   »
    
      o
      o
        0.4
        0.2
                   10       20       30
                                            40       50       60
    
    
                                           Distance Between Samplers (km)
                                                                      70       80       90       100
    Figure A-93.   PM10 inter-sampler correlations as a function of distance between monitors for
    
                   Chicago, IL
    December 2009
    A-171
    

    -------
                     Denver Combined  Statistical Area
          01
             r
                           \ Denver CSA
                         •  PMio Monitors
                        	 Interstate Highways
                            Major Highways
                                            0 10 20   40   60   80
                               100
                              m Kilometers
    Figure A-94.  PM™ monitor distribution and major highways, Denver, CO.
    December 2009
    A-172
    

    -------
             AQS Site ID
      Site A  08-001-0006
      SiteB  08-001-3001
      SiteC  08-013-0012
      SiteD  08-031-0002
      SiteE  08-031-0017
      SiteF  08-123-0006
                  1=winter
                  2=spring
                  3=summer
                  4=fall
    ABC
    Mean 36.0 28.2 19.8
    Obs 1043 1074 169
    SD 18.3 13.2 9.7
    90 -
    80 -
    70 -
    •s,
    ; '60 -
    T\
    )l
    : so -
    >
    i 40-
    J
    J
    : 30 -
    5
    J
    20 -
    r
    er 0 -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    D E F
    24.2 25.8 22.2
    1039 1028 353
    10.6 11.5 11.2
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                  1234   1234    1234   1234  1234   1234
    Figure A-95.   Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations
                  for Denver, CO.
    December 2009
    A-173
    

    -------
    Table A-39.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                    Denver, CO.
      Site
             1.00
                                0.84
                                                   0.43
                                                                      0.70
                                                                                         0.72
                                                                                                            0.67
             (0.0,0.00)
    (20.0,0.16)
    (36.0,0.34)
    (29.0, 0.24)
    (26.0,0.21)
    (27.0, 0.28)
             1043
                                1022
                                                   164
                                                                      987
                                                                                         980
                                                                                                            339
                                1.00
                                                   0.57
                                                                      0.72
                                                                                         0.74
                                                                                                            0.72
                                (0.0, 0.00)
                       (28.0, 0.27)
                       (17.0,0.18)
                       (15.0,0.16)
                       (18.0,0.22)
                                1074
                                                   169
                                                                      1019
                                                                                         1007
                                                                                                            348
                                                   1.00
                                                                      0.75
                                                                                         0.72
                                                                                                            0.51
                                                   (0.0, 0.00)
                                          (17.0,0.23)
                                          (16.0,0.23)
                                          (16.0,0.23)
                  LEGEND
    D                R
                 (P90, COD)
                     N
                                                   169
                                                                      169
                                                                                         156
                                          1.00
                                                             0.89
                                          (0.0,0.00)
                                          (9.0,0.13)
                                                                      1039
                                                                                         976
                                                                                                            164
                                                                                0.52
                                          (17.0,0.22)
                                                                                                            341
                                                                                         1.00
                                                                                                            0.58
                                                                                         (0.0, 0.00)
                                                                                (17.0,0.23)
                                                                                         1028
                                                                                                            330
                                                                                                            1.00
                                                                                                            (0.0, 0.00)
                                                                                                            353
    December 2009
                                  A-174
    

    -------
        0.8
        0.6
      o
      o
        0.4
        0.2
                   10       20       30        40       50       60
    
    
                                           Distance Between Samplers (km)
                                                                      70       80       90       100
    Figure A-96.   PM10 inter-sampler correlations as a function of distance between monitors for
    
                   Denver, CO.
    December 2009
    A-175
    

    -------
                      Detroit Combined Statistical Area
            A
           01
                             Detroit CSA
                          •  PMio Monitors
                          	 Interstate Highways
                           — Major Highways
                              0   10   20      40      60
                        80
     100
    m Kilometers
    Figure A-97.  PM™ monitor distribution and major highways, Detroit, Ml.
    December 2009
    A-176
    

    -------
               Site A  26-163-0001
               SiteB  26-163-0015
               SiteC  26-163-0033
    itelD
    0001 Mean
    0015 Obs
    0033 SD
    80 -
    70 -
    60 -
    m
    <: 50 -
    cn
    0 40 -
    Ł 3°-
    u
    c
    0
    u 20 -
    10 -
    1 =winter
    2=spring
    3=summer 0 -
    4=fall
    
    
    
    
    
    
    
    
    
    
    
    1
    ABC
    22.5 26.4 32.0
    174 176 1057
    11.8 14.9 17.9
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    234 1234 1234
    Figure A-98.  Box plots illustrating the seasonal distribution of 24-h avg PMi0 concentrations
                 for Detroit, Ml.
    December 2009
    A-177
    

    -------
    Table A-40.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
    
                  Detroit, Ml.
                                   Site
                                        1.00
                                                     0.77
                                        (0.0, 0.00)
                                        174
                                                     169
                                                     1.00
                                                                  0.74
    (14.0,0.18)      (28.0,0.26)
                                                                  172
                                                                  0.79
                                           LEGEND    (0.0,0.00)      (21.0,0.21)
    
    
                                              R      176          174
    
    
                                          (P90,COD)                1-00
    
    
                                              N                   (0.0,0.00)
                                                                  1057
         0.8
         0.6
       o
       o
         0.4
         0.2
                     10        20        30       40        50        60        70
    
    
                                              Distance Between Samplers (km)
                                                                                     80
                                                                                               90
                                                                                                        100
    Figure A-99.   PM10 inter-sampler correlations as a function of distance between monitors for
    
                    Detroit, Ml.
    December 2009
    A-178
    

    -------
                     Houston Combined Statistical Area
          01
             r
                           J Houston CSA
                         •  PMio Monitors
                         	 Interstate Highways
                            Major Highways
                                          0  10 20   40    60    80
                            100
                           —i Kilometers
    Figure A-100. PM™ monitor distribution and major highways, Houston, TX.
    December 2009
    A-179
    

    -------
              AQS Site ID
       Site A 48-201-0024
       SiteB 48-201-0047
       SiteC 48-201-0062
       SiteD 48-201-0066
       SiteE 48-201-0071
       SiteF 48-201-1035
       SiteG 48-201-1039
                       01
    
                       c
                       o
                       -4— »
                       fD
                       C
                       o>
                       u
                       c
                       o
                 1=winter
                 2=spring
                 3=summer
                 4=fall
    A
    Mean 24.5
    Obs 174
    SD 9.7
    170 -
    160 -
    150 -
    140 -
    130 -
    120 -
    110 -
    100 -
    90 -
    80 -
    70 -
    60 -
    50 -
    40 -
    30 -
    20 -
    10 -
    0 -
    
    
    
    
    
    
    
    
    
    
    
    
    
    I 1
    r
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    i
    
    BCD
    24.0 23.4 22.3
    178 174 175
    9.1 9.7 10.0
    
    
    
    
    
    
    
    
    
    
    
    
    i
    li
    ''"
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    
    nil
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    it
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    
    E F G
    22.7 54.8 15.8
    174 359 163
    9.3 35.5 7.7
    
    
    
    
    
    
    
    
    
    
    
    
    
    I I
    j flf
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I
    --•''
    
                                  1234   1234  1234   1234   1234  1234   1234
    Figure A-101.   Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations
                   for Houston, TX.
    December 2009
    A-180
    

    -------
    Table A-41.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                 Houston, TX.
    SITE ABC
    A 1.00 0.84 0.78
    (0.0,0.00) (9.0,0.12) (11.0,0.16)
    174 163 158
    B 1.00 0.86
    (0.0,0.00) (9.0,0.11)
    178 156
    C 1.00
    (0.0, 0.00)
    174
    D
    
    
    E
    LEGEND
    R
    F (P90, COD)
    N
    
    G
    D
    0.76
    (12.0,0.16)
    165
    0.86
    (9.0,0.12)
    160
    0.83
    (10.0,0.14)
    156
    1.00
    (0.0, 0.00)
    175
    
    
    
    
    
    
    
    E
    0.43
    (15.0,0.20)
    167
    0.38
    (15.0,0.19)
    163
    0.41
    (17.0,0.19)
    159
    0.32
    (18.0,0.20)
    163
    1.00
    (0.0, 0.00)
    174
    
    
    
    
    F
    0.56
    (77.0, 0.37)
    159
    0.52
    (74.0, 0.39)
    158
    0.38
    (74.0, 0.40)
    151
    0.43
    (81.0,0.43)
    155
    0.15
    (78.0, 0.43)
    158
    1.00
    (0.0, 0.00)
    359
    
    G
    0.75
    (17.0,0.28)
    156
    0.79
    (16.0,0.26)
    152
    0.85
    (14.5,0.25)
    150
    0.76
    (16.0,0.23)
    154
    0.38
    (20.0, 0.28)
    157
    0.37
    (92.0, 0.54)
    149
    1.00
    (0.0, 0.00)
    163
    December 2009                                  A-181
    

    -------
                                                Houston
                     ••  •      .     *
        0.8
        0.6
        0.4
        0.2
           0        10       20       30
                                            40       50       60       70
                                           Distance Between Samplers (km)
                                                                              80       90       100
    Figure A-102.  PMio inter-sampler correlations as a function of distance between monitors for
                   Houston, TX.
    December 2009
    A-182
    

    -------
                 Los Angeles Core Based Statistical Area
          01
             r
                            Los Angeles CBSA
                         •  PMio Monitors
                         	 Interstate Highways
                            Major Highways
                                0   10  20       40      60      80
                                100
                               —i Kilometers
    Figure A-103. PM™ monitor distribution and major highways, Los Angeles, CA.
    December 2009
    A-183
    

    -------
                       AQSSitelD
                Site A  06-037-0002
                SiteB  06-037-1103
                SiteC  06-037-4002
                SiteD  06-037-6012
                Site E  06-037-9033
                Site F  06-059-0007
                SiteG  06-059-2022
                           1=winter
                           2=spring
                           3=summer
                           4=fall
    A B C D E F G
    /lean 35.3 31.1 31.5 27.3 23.7 33.5 21.6
    Obs 169 175 178 176 985 175 162
    SD 19.8 13.3 19.6 18.1 12.1 37.6 9.4
    90 -
    80 -
    70-
    60-
    50 -
    40-
    30-
    20 -
    1 0 -
    o -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    1234 1234 1234 1234 1234 12
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    34 1234
    Figure A-104.  Box plots illustrating the seasonal distribution of 24-h avg PMi0 concentrations
                    for Los Angeles, CA.
    December 2009
    A-184
    

    -------
    Table A-42.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                 Los Angeles, CA.
    Site A B C
    A 1.00 0.73 0.44
    (0.0,0.00) (17.0,0.17) (27.0,0.24)
    169 153 154
    B 1.00 0.61
    (0.0,0.00) (14.0,0.14)
    175 159
    C 1.00
    LEGEND (O.o.o.oo)
    Pearson R ^
    
    (1 BU.tUUU)
    
    E
    
    
    F
    
    
    G
    D
    0.73
    (24.0, 0.22)
    157
    0.57
    (21.0,0.24)
    159
    0.65
    (27.0, 0.28)
    158
    1.00
    (0.0, 0.00)
    176
    
    
    
    
    
    
    
    E
    0.47
    (28.0, 0.26)
    169
    0.52
    (23.0, 0.23)
    173
    0.43
    (22.0, 0.24)
    176
    0.70
    (16.0,0.20)
    175
    1.00
    (0.0, 0.00)
    985
    
    
    
    
    F
    0.41
    (29.0, 0.24)
    155
    0.42
    (15.0,0.16)
    162
    0.93
    (11.0,0.11)
    159
    0.65
    (26.0, 0.28)
    161
    0.29
    (26.0, 0.25)
    173
    1.00
    (0.0, 0.00)
    175
    
    G
    0.65
    (30.0, 0.28)
    143
    0.73
    (20.0, 0.23)
    149
    0.73
    (21.0,0.22)
    148
    0.57
    (19.5,0.24)
    150
    0.38
    (20.0, 0.24)
    159
    0.65
    (21.5,0.22)
    150
    1.00
    (0.0, 0.00)
    162
        0.8
        0.6
        0.4
        0.2
                   10       20       30       40       50       60       70
    
                                           Distance Between Samplers (km)
                                                                              80
                                                                                      90
                                                                                              100
    Figure A-105.  PMio inter-sampler correlations as a function of distance between monitors for
                   Los Angeles, CA.
    December 2009
    A-185
    

    -------
                    New York Combined Statistical Area
            A
          01
             r
                            New York CSA
                         •   PMio Monitors
                         	 Interstate Highways
                          — Major Highways
    
    0 10 20   40   60   80  100
    •Z«Z^^^H^Z^Z^^^B^Z^ZI Kilometers
    Figure A-106.  PM™ monitor distribution and major highways, New York, NY.
    December 2009
    A-186
    

    -------
                              60-
                              50-
                              40-
                        I    30 H
    
                        Ł
                        "c
                         CD
                         O
    
                         O    20 H
                         O
                              10-
                               0-
    Figure A-107.  Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations
    
                  for New York, NY.
    December 2009
    A-187
    

    -------
    Table A-43.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
    
                 New York, NY.
    Site
    A
    
    
    B
    
    
    C
    
    A
    1.00
    (0.0, 0.00)
    167
    
    LEGEND
    R
    (P90, COD)
    N
    B
    0.88
    (11.0,0.20)
    156
    1.00
    (0.0, 0.00)
    169
    
    
    C
    0.82
    (12.0,0.16)
    164
    0.74
    (18.0,0.25)
    166
    1.00
    (0.0, 0.00)
    178
          1 t
        0.8
        0.6
       o
    
       1
       HI
        0.4
        0.2
                   10       20       30       40       50       60
    
    
                                           Distance Between Samplers (km)
                                                                      70
                                                                              80
                                                                                       90
                                                                                               100
    Figure A-108.  PM10 inter-sampler correlations as a function of distance between monitors for
    
                   New York, NY.
    December 2009
    A-188
    

    -------
                  Philadelphia Combined Statistical Area
            A
          01
                             Philadelphia CSA
                          •   PMio Monitors
                         	 Interstate Highways
                           — Major Highways
                                      0  10  20     40     60     80
                               100
                              —i Kilometers
    Figure A-109. PM™ monitor distribution and major highways, Philadelphia, PA.
    December 2009
    A-189
    

    -------
                          AQS Site ID
                   Site A  10-003-2004
                   SiteB  42-017-0012
                   SiteC  42-045-0002
                   SiteD  42-091-0013
                               2=spring
                               3=surr
                               4=fail
    A B C D
    Mean 22.8 17.1 19.9 17.6
    Obs 1059 1040 1059 1049
    SD 11.7 9.3 9.4 9.8
    60 -
    50 -
    "Ł 40 -
    01
    c
    .2 30 -
    ro
    4-"
    C
    01
    Ł 20-
    O
    u
    10 -
    er
    ig
    mer -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                              1234  1234  12341234
    Figure A-110.  Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations
                  for Philadelphia, PA.
    December 2009
    A-190
    

    -------
    Table A-44.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                 Philadelphia, PA.
    Site
    A
    
    
    B
    
    
    C
    
    
    D
    
    A
    1.00
    (0.0, 0.00)
    1059
    
    
    
    
    LEGEND
    R
    (P90, COD)
    N
    B
    0.81
    (13.0,0.21)
    1005
    1.00
    (0.0, 0.00)
    1040
    
    
    
    
    
    C
    0.64
    (14.0,0.19)
    1025
    0.71
    (11.0,0.20)
    1006
    1.00
    (0.0, 0.00)
    1059
    
    
    D
    0.84
    (12.0,0.20)
    1013
    0.93
    (6.0,0.12)
    994
    0.73
    (11.0,0.19)
    1014
    1.00
    (0.0, 0.00)
    1049
        0.8
        0.6
      01
    
      8
        0.4
        0.2
                   10       20       30       40       50       60
    
                                           Distance Between Samplers (km)
                                                                       70
                                                                               80
                                                                                        90
                                                                                                100
    Figure A-111.  PMio inter-sampler correlations as a function of distance between monitors for
                   Philadelphia, PA.
    December 2009
    A-191
    

    -------
                    Phoenix Core Based Statistical Area
            A
          01
                   \	| Phoenix CBSA
                    •  PMio Monitors
                   	 Interstate Highways
                      — Major Highways
    
          0 1020   40   60   80   100
                                i Kilometers
    Figure A-112. PM™ monitor distribution and major highways, Phoenix, AZ.
    December 2009
    A-192
    

    -------
                           AQS Site ID
                   Site A  04-013-0019
                   SiteB  04-013-1003
                   SiteC  04-013-1004
                   SiteD  04-013-3002
                   SiteE  04-013-3003
                   SiteF  04-013-3010
                   SiteG  04-013-4003
                   SiteH  04-013-4004
                              2=spring
                              3=sum
                              4=fall
    
                            AQS Site ID
                           04-013-4006
                           04-013-4009
                           04-013-4010
                           04-013-4011
                    SiteM  04-013-8006
                    SiteN  04-013-9812
                    SiteO  04-013-9997
                    SiteP  04-021-0001
    Site I
    SiteJ
    SiteK
    SiteL
                             1= winter
                             2=spring
                             3=sum
                             4=fall
    ID ABCDEFGH
    19 Mean 486 30.9 32.6 40.8 325 51.5 56.6 34.7
    D3 Obs 790 179 182 1084 182 780 336 181
    34 SD 23.0 14.5 14.6 20.0 15.2 23.1 25.8 17.0
    32 26°"
    33 240 -
    10
    D3 22° '
    34 200 -
    Ł- 180 -
    E:
    ^ 140 -
    O
    'ro 12°-
    = 100 -
    OJ
    u
    5 80 -
    O
    u
    60 -
    40 -
    ter 20 -
    ng
    imer g -
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    III
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    I 1 l
    
    1 1
    
    
    
    
    
    
    
    
    
    
    
    
    
    1 i 1
    
    1 1
    
    
    
    
    
    
    
    
    
    
    
    | ,
    
    1 1
    'III !i 1
    
    
    
    
    
    
    
    
    
    
    
    
    
    i
    1
    1
    1 1 '
    1234 1234 1234 234 1234 1234 1234 1234
    ,n JKLMNOP
    ' IU Mean 55.6 75.6 32.5 53.0 58.4 65.5 34.3 49.7
    306 Obs 1073 1083 178 1090 174 1086 1067 407
    309 SD 30.6 39.5 16.1 27.8 30.9 34.9 21.3 54.2
    310 260-
    511 240-
    306
    312 220-
    397
    301
    ^ .180 -
    E
    ^ 160 -
    c 140 -
    O
    ro 120 -
    •1— '
    v 100 -
    u
    c
    O 80 -
    u
    60 -
    40 -
    ter
    ng 20-
    mer o-
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Illl
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Ill
                                              1234   1234   1234   1234   1234  1234   1234   1234
    December 2009
                                                 A-193
    

    -------
                     AQS Site ID
              SiteQ 04-021-3002
              SiteR 04-021-3004
              SiteS 04-021-3006
              Site! 04-021-3007
              SiteU 04-021-3008
              SiteV 04-021-3011
              SiteW 04-021-3012
              SiteX 04-021-7004
                       1=winter
                       2=spring
                       3=sum
                       4=fall
    ID
    32 Mean
    ™ °soS
    06 260-
    07
    08 240 -
    11
    12 22° "
    04 200 -
    ST 180 -
    E:
    Ol
    a.
    ^ 140 -
    O
    c 100 -
    cu
    u
    c 80 -
    O
    60 -
    40 -
    ter 20 -
    ng
    mer 0 -
    QRSTUVWX
    20.8 38.8 13.7 27.0 80.6 74.7 21.5 54.3
    172 171 172 175 476 475 170 322
    10.0 21.4 6.8 17.1 72.5 137.5 12.5 38.3
    
    
    
    
    
    
    
    
    
    
    !'='
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    :••-••
    
    
    
    
    
    
    
    
    
    I
    III
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    ill'
    
    
    
    
    
    
    
    
    
    
    
                                     1234  1234   1234  1234   1234  1234  1234  1234
    Figure A-113.  Box plots illustrating the seasonal distribution of 24-h avg PMi0 concentrations
                    for Phoenix, AZ.
    December 2009
    A-194
    

    -------
    Table A -45. Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
    Phoenix, AZ.
    Site AB C DEFGHI
    A 1.00 0.71 0.85 0.85 0.67 0.94 0.86 0.77 0.73
    (0.0,0.00) (38.0,0.25) (33.0,0.21) (21.0,0.12) (38.0,0.23) (14.0,0.09) (22.0,0.13) (34.0,0.21) (35.0,0.18)
    790 178 181 788 181 779 335 180 772
    B 1.00 0.84 0.82 0.85 0.67 0.74 0.81 0.67
    (0.0,0.00) (13.0,0.12) (23.0,0.19) (11.0,0.11) (37.0,0.29) (47.0,0.30) (13.0,0.13) (49.0,0.30)
    179 179 177 179 175 179 178 175
    C 1.00 0.88 0.81 0.78 0.80 0.81 0.70
    (0.0,0.00) (20.0,0.16) (12.0,0.11) (38.0,0.27) (44.0,0.28) (13.0,0.13) (48.0,0.29)
    182 180 182 178 182 181 178
    D 1.00 0.76 0.88 0.81 0.82 0.76
    (0.0,0.00) (23.0,0.17) (22.0,0.14) (29.0,0.16) (18.0,0.17) (39.0,0.20)
    1084 180 778 334 179 1062
    E 1.00 0.64 0.68 0.74 0.66
    (0.0,0.00) (40.0,0.27) (47.0,0.29) (16.0,0.14) (48.0,0.29)
    182 178 182 181 178
    F 1.00 0.83 0.76 0.75
    (0.0,0.00) (22.0,0.13) (36.0,0.25) (32.0,0.17)
    780 331 177 762
    G 1.00 0.77 0.65
    (0.0,0.00) (44.0,0.26) (38.0,0.19)
    336 181 326
    H 1.00 0.79
    (0.0, 0.00) (47.0, 0.26)
    R 181 m
    i (P90COD) 100
    (0.0, 0.00)
    1073
    J
    
    
    K
    
    
    L
    
    
    M
    J
    0.83
    (59.0, 0.24)
    781
    0.68
    (84.0, 0.43)
    176
    0.73
    (84.0,0.41)
    179
    0.78
    (71.0,0.31)
    1072
    0.59
    (88.0, 0.42)
    179
    0.86
    (54.0,0.21)
    772
    0.78
    (48.0,0.19)
    333
    0.81
    (79.0, 0.39)
    178
    0.79
    (52.0, 0.22)
    1061
    1.00
    (0.0, 0.00)
    1083
    
    
    
    
    
    
    
    K
    0.77
    (34.0, 0.24)
    177
    0.75
    (16.0,0.15)
    175
    0.81
    (15.0,0.14)
    178
    0.79
    (22.0,0.19)
    176
    0.67
    (15.0,0.15)
    178
    0.74
    (41.0,0.28)
    175
    0.71
    (46.0, 0.30)
    178
    0.79
    (16.0,0.14)
    177
    0.76
    (48.0, 0.29)
    174
    0.78
    (83.0, 0.42)
    175
    1.00
    (0.0, 0.00)
    178
    
    
    
    
    L
    0.70
    (30.0,0.17)
    789
    0.60
    (51.0,0.31)
    178
    0.63
    (49.0, 0.29)
    181
    0.65
    (35.0, 0.20)
    1080
    0.51
    (49.0, 0.30)
    181
    0.69
    (30.0,0.17)
    779
    0.65
    (36.0,0.19)
    335
    0.69
    (43.0, 0.27)
    180
    0.69
    (33.0,0.17)
    1068
    0.73
    (57.0, 0.23)
    1078
    0.72
    (45.0, 0.29)
    177
    1.00
    (0.0, 0.00)
    1090
    
    M
    0.87
    (28.5,0.16)
    170
    0.63
    (56.0, 0.32)
    164
    0.75
    (55.0, 0.30)
    167
    0.83
    (42.0,0.21)
    172
    0.61
    (58.0,0.31)
    167
    0.87
    (25.0,0.15)
    167
    0.80
    (33.0,0.16)
    169
    0.72
    (53.0, 0.29)
    167
    0.68
    (38.0, 0.20)
    171
    0.80
    (51.0,0.22)
    171
    0.68
    (56.0, 0.32)
    164
    0.63
    (42.0, 0.20)
    173
    1.00
    (0.0, 0.00)
    174
    December 2009                                      A-195
    

    -------
    
    A
    
    
    B
    
    
    C
    
    
    D
    
    
    E
    
    
    H
    
    
    G
    
    
    H
    
    
    1
    
    
    J
    
    
    K
    
    
    L
    
    
    M
    
    
    N
    
    
    0
    
    
    P
    
    
    Q
    
    
    R
    
    
    S
    
    
    T
    
    
    U
    
    
    V
    
    
    W
    
    
    X
    N
    0.87
    (39.0,0.18)
    784
    0.59
    (67.0, 0.37)
    178
    0.70
    (69.0, 0.35)
    181
    0.78
    (57.0, 0.25)
    1075
    0.60
    (67.0, 0.35)
    181
    0.91
    (35.0, 0.14)
    774
    0.77
    (35.0,0.16)
    332
    0.70
    (66.0, 0.33)
    180
    0.76
    (42.0,0.18)
    1064
    0.91
    (29.0,0.12)
    1074
    0.69
    (73.0, 0.36)
    177
    0.68
    (48.0, 0.20)
    1081
    0.86
    (32.0,0.16)
    173
    1.00
    (0.0, 0.00)
    1086
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    0
    0.68
    (28.0,0.17)
    783
    0.75
    (15.0,0.15)
    179
    0.87
    (11.0,0.12)
    182
    0.86
    (15.0,0.12)
    1056
    0.73
    (14.0,0.14)
    182
    0.68
    (31.0,0.21)
    773
    0.57
    (41.0,0.25)
    336
    0.75
    (15.0,0.14)
    181
    0.61
    (49.0, 0.27)
    1045
    0.58
    (83.0, 0.38)
    1055
    0.71
    (16.0,0.16)
    178
    0.55
    (44.0, 0.26)
    1063
    0.81
    (53.0, 0.29)
    174
    0.58
    (66.0, 0.32)
    1059
    1.00
    (0.0, 0.00)
    1067
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    P
    0.47
    (29.0,0.19)
    406
    0.75
    (22.0,0.17)
    175
    0.80
    (19.0,0.15)
    178
    0.73
    (30.0,0.19)
    405
    0.68
    (21.0,0.17)
    178
    0.46
    (30.0, 0.22)
    403
    0.47
    (36.5, 0.24)
    330
    0.82
    (18.0,0.15)
    177
    0.52
    (39.0, 0.22)
    397
    0.41
    (68.0,0.31)
    404
    0.75
    (19.0,0.18)
    174
    0.51
    (37.0, 0.22)
    406
    0.75
    (47.0, 0.30)
    165
    0.41
    (51.0,0.27)
    403
    0.90
    (35.0, 0.22)
    407
    1.00
    (0.0, 0.00)
    407
    
    
    
    
    
    
    
    
    
    
    Q
    0.53
    (49.0, 0.42)
    171
    0.73
    (23.0, 0.27)
    169
    0.70
    (24.0, 0.28)
    172
    0.63
    (38.0, 0.38)
    170
    0.72
    (21.0,0.28)
    172
    0.48
    (60.0, 0.46)
    169
    0.55
    (61.0,0.47)
    172
    0.63
    (29.0,0.31)
    171
    0.57
    (66.0, 0.47)
    169
    0.48
    (103.0,0.58)
    169
    0.52
    (28.0, 0.29)
    168
    0.47
    (66.0, 0.47)
    171
    0.48
    (74.0, 0.48)
    157
    0.48
    (88.0, 0.53)
    171
    0.61
    (28.0,0.31)
    172
    0.67
    (32.0, 0.29)
    169
    1.00
    (0.0, 0.00)
    172
    
    
    
    
    
    
    
    LEGEND
    R
    (P90, COD)
    N
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    R
    0.68
    (34.0, 0.27)
    171
    0.63
    (30.0, 0.25)
    168
    0.71
    (26.0, 0.24)
    171
    0.68
    (27.0, 0.25)
    169
    0.64
    (27.0, 0.24)
    171
    0.63
    (37.0, 0.30)
    167
    0.65
    (41.0,0.30)
    171
    0.74
    (24.5, 0.22)
    170
    0.71
    (41.0,0.27)
    168
    0.65
    (75.0, 0.40)
    168
    0.64
    (27.0, 0.23)
    167
    0.57
    (44.5, 0.29)
    170
    0.64
    (51.0,0.32)
    158
    0.67
    (62.5, 0.35)
    170
    0.64
    (25.0, 0.24)
    171
    0.81
    (22.0,0.19)
    170
    0.72
    (40.0, 0.33)
    162
    1.00
    (0.0, 0.00)
    171
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    S
    0.40
    (64.0, 0.57)
    171
    0.55
    (32.0, 0.43)
    169
    0.48
    (36.0, 0.44)
    172
    0.49
    (46.0, 0.53)
    170
    0.43
    (33.0, 0.44)
    172
    0.38
    (68.0, 0.60)
    168
    0.46
    (73.0,0.61)
    172
    0.55
    (37.0, 0.46)
    171
    0.51
    (77.0, 0.60)
    168
    0.48
    (115.0,0.69)
    169
    0.52
    (34.0, 0.44)
    168
    0.48
    (71.0,0.60)
    171
    0.37
    (80.0,0.61)
    158
    0.42
    (98.0, 0.65)
    171
    0.39
    (38.0, 0.47)
    172
    0.58
    (44.0, 0.45)
    169
    0.65
    (15.0,0.28)
    163
    0.66
    (55.0, 0.48)
    162
    1.00
    (0.0, 0.00)
    172
    
    
    
    
    
    
    
    
    
    
    
    
    
    T
    0.69
    (40.0, 0.34)
    174
    0.59
    (21.0,0.24)
    172
    0.64
    (22.0, 0.24)
    175
    0.65
    (31.0,0.31)
    173
    0.48
    (21.0,0.25)
    175
    0.63
    (45.0, 0.39)
    172
    0.62
    (58.0,0.41)
    175
    0.62
    (24.0, 0.25)
    174
    0.58
    (60.0, 0.40)
    171
    0.65
    (92.0,0.51)
    172
    0.62
    (22.0, 0.24)
    171
    0.49
    (62.0, 0.40)
    174
    0.62
    (58.5,0.41)
    160
    0.63
    (75.0, 0.46)
    174
    0.60
    (22.0, 0.26)
    175
    0.78
    (21.0,0.21)
    172
    0.57
    (23.0, 0.24)
    167
    0.68
    (32.0, 0.27)
    165
    0.60
    (28.0, 0.35)
    167
    1.00
    (0.0, 0.00)
    175
    
    
    
    
    
    
    
    
    
    
    U
    0.50
    (82.0,0.31)
    475
    0.53
    (94.0,0.41)
    172
    0.56
    (91.0,0.40)
    175
    0.66
    (87.0, 0.34)
    474
    0.42
    (93.0,0.41)
    175
    0.47
    (80.0,0.31)
    470
    0.49
    (78.0, 0.28)
    329
    0.60
    (84.0, 0.38)
    174
    0.59
    (72.0, 0.27)
    461
    0.51
    (69.0, 0.26)
    473
    0.71
    (89.0, 0.40)
    171
    0.59
    (75.0, 0.27)
    475
    0.46
    (62.0,0.31)
    165
    0.42
    (71.0,0.29)
    470
    0.72
    (94.0, 0.39)
    475
    0.82
    (80.0, 0.30)
    400
    0.36
    (104.0,0.53)
    165
    0.53
    (75.0, 0.35)
    164
    0.46
    (115.0,0.65)
    165
    0.56
    (94.0, 0.47)
    169
    1.00
    (0.0, 0.00)
    476
    
    
    
    
    
    
    
    V
    0.27
    (49.0, 0.27)
    474
    0.66
    (62.0, 0.34)
    177
    0.71
    (59.0, 0.32)
    180
    0.45
    (59.0, 0.30)
    473
    0.69
    (63.0, 0.32)
    180
    0.28
    (50.0, 0.27)
    469
    0.44
    (45.0, 0.24)
    334
    0.76
    (58.0, 0.29)
    179
    0.37
    (46.0, 0.23)
    461
    0.28
    (59.0, 0.27)
    472
    0.68
    (59.0, 0.33)
    176
    0.33
    (53.0, 0.24)
    474
    0.65
    (48.0, 0.26)
    168
    0.26
    (55.0, 0.27)
    469
    0.59
    (69.0, 0.35)
    473
    0.64
    (52.0, 0.23)
    404
    0.58
    (78.0, 0.46)
    171
    0.82
    (47.0, 0.25)
    171
    0.59
    (86.0, 0.59)
    171
    0.66
    (71.0,0.39)
    174
    0.54
    (66.0, 0.24)
    464
    1.00
    (0.0, 0.00)
    475
    
    
    
    
    W
    0.56
    (48.0, 0.43)
    169
    0.65
    (24.0, 0.30)
    167
    0.62
    (28.0,0.31)
    170
    0.58
    (38.0, 0.39)
    168
    0.51
    (25.0, 0.32)
    170
    0.42
    (57.0, 0.47)
    166
    0.57
    (59.0, 0.48)
    170
    0.64
    (30.0, 0.33)
    169
    0.51
    (63.0, 0.47)
    167
    0.46
    (101.0,0.58)
    167
    0.55
    (28.0, 0.32)
    166
    0.50
    (67.0, 0.48)
    169
    0.44
    (68.0, 0.49)
    156
    0.40
    (88.0, 0.54)
    169
    0.55
    (29.0, 0.33)
    170
    0.71
    (32.0,0.31)
    167
    0.68
    (15.0,0.22)
    161
    0.68
    (40.0, 0.34)
    160
    0.72
    (19.0,0.28)
    162
    0.68
    (18.0,0.24)
    165
    0.52
    (101.0,0.53)
    165
    0.60
    (78.0, 0.47)
    169
    1.00
    (0.0, 0.00)
    170
    
    X
    0.65
    (31.0,0.20)
    262
    0.64
    (46.0, 0.29)
    155
    0.60
    (43.0, 0.28)
    157
    0.70
    (32.0,0.21)
    318
    0.52
    (46.0, 0.28)
    157
    0.66
    (34.0, 0.22)
    259
    0.64
    (32.0, 0.22)
    185
    0.76
    (39.0, 0.25)
    156
    0.80
    (30.0,0.16)
    314
    0.74
    (62.0, 0.27)
    319
    0.68
    (44.0, 0.29)
    153
    0.68
    (29.0,0.18)
    321
    0.59
    (42.0, 0.24)
    145
    0.60
    (48.0, 0.24)
    319
    0.64
    (44.0, 0.26)
    317
    0.67
    (39.0, 0.24)
    197
    0.47
    (62.0, 0.43)
    148
    0.68
    (39.0, 0.24)
    148
    0.52
    (74.0, 0.58)
    149
    0.61
    (51.5,0.37)
    150
    0.71
    (61.0,0.25)
    204
    0.64
    (35.0, 0.20)
    206
    0.56
    (63.0, 0.44)
    145
    1.00
    (0.0, 0.00)
    322
    December 2009
    A-196
    

    -------
       0.8
    • * •••
     •  ++
    
    v~  **  **r  /;*•.*  *      *   ^
          ** **; '*:  **<**/*«*  *******
            *     K*      * ** *  » 4    *       * ^
     *        **»•»*•»«    ^*.***»  «.**«^
            » » »   *    **»%   *^   *****   ~ **
       0.6
                                                       *****  *
      •s
      oi
    
      5
      o
       0.4
       0.2
                                         *
    
    
                                         *
                                                           *
                10     20      30     40      50     60
    
    
                                  Distance Between Samplers (km)
                                                       70
                                                             80
                                                                    90
                                                                          100
    Figure A-114. PM10 inter-sampler correlations as a function of distance between monitors for
    
               Phoenix, AZ.
    December 2009
                               A-197
    

    -------
            A
          01
                    Pittsburgh Combined  Statistical Area
                             Pittsburgh CSA
                             PMio Monitors
                             Interstate Highways
                             Major Highways
                            0    10   20       40       60
                        80
     100
    m Kilometers
    Figure A-115. PM™ monitor distribution and major highways, Pittsburgh, PA.
    December 2009
    A-198
    

    -------
    Obs
    SD
    90-
    AQSStelD
    SiteA 42-003-0002 80-
    SiteB 42-003«)21
    SiteC 42-003-0031 70-
    SiteD 42-003-0064 j-
    SiteE 42-003-0092 ^ 60"
    Site F 42-003-0095 2
    SiteG 42-003-0116 "^ 50"
    SieH 42-003-1301 -
    03 40-
    § 30-
    c
    o
    u 20-
    10-
    1=winter
    2=spring 0 "
    3=summer
    Wall _10.
    1077 1019 1083 1087
    12.9 11.4 12.3 20.3
    
    
    
    
    
    
    
    
    
    f
    
    
    176 179 978 182 1022
    11. 9.9 11.7 16.8 19.3
    
    
    
    
    
    
    
    
    
    ' f
    
    
                                             1234 12341234  1234 1234  1234 12341234  1234
                          Stel  42-003-3006
                          SteJ  42-003-3007
                          Ste K  42-003-7004
                          Site L  42-007-0014
                          SiteM 42-073-0015
                          SteN  42-125-0005
                          SiteO 42-125-5001
                          SiKP  42-129-0007
                          SiteQ 42-12*0008
    J K L M N O P Q
    Wtan 20.1 36.5 26.3 26.4 21.7 19.7 27.3 21.1
    Obs 177 1061 1051 1069 1092 167 178 1079
    SD
    UO-
    ItelD no.
    006
    007 10°"
    004 „ 90-
    1014 "c
    1015 Tj, 80-
    005 ""
    c 70-
    001 o
    1007 U 60-
    KX8 Z
    Ł 50-
    0 40-
    u
    30-
    20-
    1 -winter
    2-spring 1 0 -
    3~summer
    4=fall 0 -
    10.3 26.7 16.3 15.0 12.4 11.0 12.0 11.4
    
    
    
    
    
    
    
    
    
    
    )
    
    
    
    
    
    
    
    
    
    
    
    
    I
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    \
    
    
                                               1234 1234  1234  1234  1234  1234  1234  1234
    Figure A-116.  Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations
                     for Pittsburgh,  PA.
    December 2009
    A-199
    

    -------
    Table A-46.   Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                 Pittsburgh, PA.
    Site
    A
    
    t
    R
    
    
    C
    
    
    D
    
    
    E
    
    
    	 E 	
    
    G
    
    
    H
    
    
    I
    A
    1 nn
    inn oooi in
    1077
    
    in
    
    
    
    
    
    
    
    
    LEGEND
    Pearson R
    (P90, COD)
    n
    
    
    
    
    
    
    B C
    Hen Hen
    0 01S) (80 014)
    1009 106S
    1 00 0 96
    0 000) (80 015)
    1019 1007
    1 00
    (00 000)
    1083
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    D
    nan
    (930 091)
    1070
    080
    (990 094)
    1019
    081
    (930 090)
    1075
    100
    (000 00)
    1087
    
    
    
    
    
    
    
    
    
    
    
    
    
    E
    na9
    (80 019)
    175
    091
    (11 0 090)
    163
    094
    (60 011)
    173
    079
    (91 0 0 90)
    176
    100
    (000 00)
    176
    
    
    
    
    
    
    
    
    
    
    F
    n 80
    (140 018)
    178
    099
    (60 016)
    166
    093
    (70 019)
    176
    066
    (96 0 0 94)
    179
    090
    (100 014)
    173
    1 00
    (00 000)
    179
    
    
    
    
    
    
    
    G
    noT
    (800 14)
    960
    097
    (50 010)
    911
    094
    (80 013)
    966
    076
    (970 094)
    970
    090
    (100 017)
    154
    094
    (70 019)
    157
    1 00
    (000 00)
    978
    
    
    
    
    H
    n?Q
    (160 017)
    181
    081
    (95 0 0 99)
    169
    077
    (91 0 0 99)
    179
    083
    (140 018)
    189
    078
    (90 0 0 90)
    175
    070
    (95 0 0 97)
    178
    070
    (99 0 0 98)
    160
    1 00
    (00 000)
    189
    
    1
    n RR
    (180 018)
    1005
    089
    (99 0 0 90)
    954
    087
    (190 017)
    1010
    088
    (160 014)
    1014
    077
    (900 019)
    166
    074
    (95 0 0 99)
    168
    087
    (900 019)
    910
    076
    (170 090)
    171
    1 00
    in n n nm
    1099
    
    
    A
    
    
    R
    
    
    0
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    
    
    .1
    
    
    K
    
    
    L
    
    
    M
    
    
    N
    
    
    0
    
    
    P
    
    
    Q
    
    
    J
    flM
    (14 n n 9m
    176
    093
    (7 n mm
    164
    nnn
    (80 0131
    174
    n?3
    (94 n n 99)
    177
    086
    MOO 016)
    171
    am
    (70 0191
    174
    099
    (70 0131
    156
    074
    (93 0 0 96)
    176
    079
    (99 0 0 90)
    166
    1 00
    (000 00)
    177
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    K
    H7fi
    (400 030)
    1044
    076
    (43 0 0 36)
    986
    075
    (390 030)
    1049
    084
    (94 0 0 99)
    1055
    065
    (360 099)
    169
    057
    (41 0 0 34)
    179
    073
    (450 035)
    955
    068
    (96 0 0 99)
    175
    083
    (300 095)
    999
    066
    (44 5 0 33)
    170
    1 00
    (00 0 00)
    1061
    
    
    
    
    
    LEGEND
    Pearson F
    (P90, COD
    n
    
    
    
    
    
    
    
    L
    nss
    (150 018)
    1033
    088
    (190 093)
    989
    088
    (140 017)
    1039
    080
    (900 018)
    1043
    083
    (160 016)
    169
    089
    (900 090)
    179
    087
    (180 091)
    938
    077
    (150 018)
    175
    089
    (160 017)
    978
    079
    (180 090)
    170
    074
    (310 096)
    1017
    100
    (00 0 00)
    1051
    
    
    
    
    t
    I)
    
    
    
    
    
    
    
    
    
    M
    ns5
    (160 019)
    1059
    081
    (90 0 0 96)
    994
    083
    (150 019)
    1057
    078
    (90 0 0 90)
    1061
    080
    (140 017)
    179
    075
    (190 099)
    175
    078
    (190 094)
    959
    078
    (170 018)
    178
    078
    (180 090)
    998
    079
    (180 099)
    173
    075
    (33 0 0 94)
    1035
    087
    (130 016)
    1095
    100
    (00 0 00)
    1069
    
    
    
    
    
    
    
    
    
    
    
    
    N
    nsfi
    (11 0 016)
    1074
    091
    (100 016)
    1016
    089
    (90 019)
    1080
    076
    (95 0 0 90)
    1084
    084
    (190 014)
    176
    086
    (11 0 014)
    179
    089
    (90 015)
    975
    074
    (91 0 0 99)
    189
    081
    (900 017)
    1019
    088
    (80 013)
    177
    070
    (40 0 0 30)
    1058
    085
    (160 017)
    1048
    074
    (180 091)
    1067
    100
    (00 0 00)
    1099
    
    
    
    
    
    
    
    
    
    0
    nn
    (160 099)
    166
    076
    (190 019)
    157
    078
    (190 018)
    164
    057
    (980 096)
    167
    077
    (140 019)
    161
    083
    (90 015)
    164
    081
    (11 0 017)
    146
    060
    (970 099)
    167
    066
    (960 094)
    158
    078
    (11 0 017)
    163
    047
    (44 0 0 36)
    160
    070
    (99 0 0 94)
    160
    064
    (190 096)
    163
    0.79
    (130 018)
    167
    100
    (00 0 00)
    167
    
    
    
    
    
    
    P
    H7R
    (150 019)
    177
    083
    (1800 98)
    165
    088
    (130 019)
    175
    064
    (90 0 0 95)
    178
    084
    (130 016)
    179
    084
    (160 099)
    175
    084
    (170 096)
    157
    065
    (190 099)
    177
    069
    (91 0 0 95)
    167
    086
    (160 091)
    173
    058
    (34 0 0 30)
    171
    074
    (170 091)
    171
    067
    (170 099)
    174
    086
    (140 090)
    178
    075
    (180 095)
    163
    100
    (00 0 00)
    178
    
    
    
    Q
    nsfi
    (11 0 015)
    1061
    088
    (100 018)
    1003
    090
    (90 019)
    1067
    074
    (960 091)
    1071
    085
    (11 0 015)
    174
    086
    (90 014)
    177
    086
    (100 016)
    967
    076
    (91 5 0 94)
    180
    078
    (990 019)
    1009
    086
    (80 015)
    175
    068
    (43 0 0 30)
    1048
    080
    (180 019)
    1035
    077
    (180 019)
    1053
    086
    (100 014)
    1076
    069
    (140 019)
    165
    084
    (150 091)
    176
    100
    (00 000)
    1079
    December 2009
    A-200
    

    -------
        0.8
               *   ••  *   *            V   *   *
            *           4     »   «   *^ » *   *    *
             *         »'    »***   *  **   **•   *»
            \    *         »     V  .«*«••*
                 »    ^    »  »    ^  »*
                                                             -»^«  *^
        0.6
        0.4 -
        0.2
           0       10       20       30
                                             40        50       60       70
    
    
                                           Distance Between Samplers (km)
                                                                                        90       100
    Figure A-117.  PM10 inter-sampler correlations as a function of distance between monitors for
    
                   Pittsburgh, PA.
    December 2009
    A-201
    

    -------
                    Riverside Core Based Statistical Area
            A
           01
                           \ Riverside CBSA
                          •  PMio Monitors
                         	 Interstate Highways
                           — Major Highways
                                           0  15 30    60    90   120
                               150
                              —i Kilometers
    Figure A-118.  PM™ monitor distribution and major highways, Riverside, CA.
    December 2009
    A-202
    

    -------
                      Site A
                      SiteB
                      SiteC
                      SiteD
                      SiteE
                      SiteF
          AQS Site ID
         06-065-0003
         06-065-2002
         06-065-5001
         06-065-6001
         06-065-8001
         06-071-0013
            A
     Mean   37.6
      Obs   174
      SD   27.9
    130  -"
    
    120  -
     B       C       D        E        F       G
    52.3     28.0     53.6      55.1      24.6     43.5
    315     170     173      358      177     181
    27.4     21.1     91.9      35.4      20.9     24.8
                      SiteG 06-071-0025  110 -
                                       100 -
                                       , 90 -
                                    0>  80 -
                                    c
                                    o
            1=winter
            2=spring
            3=summer
            4=fall
    
           AQS Site ID
    SiteH 06-071-0306
    Site I  06-071-1234
          06-071-2002
          06-071-4001
          06-071-4003
     70
    
     60
    
     50
    
     40
    
     30
    
     20 -
    
     10 -
                      SiteJ
                      SiteK
                      SiteL
                                                          20.6
                                                          1015
                                                          15.4
                      SiteM  06-071-9004
                                      E:
                                      01
                                      c
                                      QJ
                                      U
                                1=winter
                                2=spring
                                3=summer
                                4=fall
          1234  1234   1
               H        I
       Mean   31.4
        Obs   1060
         SD   20.2
      130 -
    
      120 -
    
      110 -
    
      100 -
    
       90 -
                        70 -
    
    
    
                        50 -
    
                        40 -
    
                        30 -
    
                        20 -
    
    
    
                         0 -
            234   1
                 J
                54.4
                178
    234  1
         K
        29.6
        173
        13.6
                                                                               234
     1234
     L
    36.5
    178
    20.2
    1234
      M
     47.7
     175
                                                1234   1234   1234   1234   1234   1234
    Figure A-119.   Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations
                      for Riverside, CA.
    December 2009
                                         A-203
    

    -------
    Table A-47. Inter-sampler correlation statistics for each pair of PMio
    Riverside, CA.
    
    A
    
    
    B
    
    
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    
    
    J
    
    
    K
    
    
    L
    
    
    M
    A B C D E F G
    1.00 0.09 0.15 0.90 0.94 0.25 0.94
    (0.0,0.00) (50.0,0.31) (36.0,0.32) (33.0,0.19) (37.0,0.24) (41.0,0.38) (16.0,0.13)
    174 170 155 165 172 169 171
    1.00 0.86 0.07 0.13 0.31 0.12
    (0.0,0.00) (48.0,0.37) (47.0,0.28) (45.0,0.27) (57.0,0.47) (49.0,0.26)
    315 161 167 298 173 176
    1.00 0.13 0.21 0.36 0.20
    (0.0,0.00) (49.0,0.37) (58.0,0.42) (24.0,0.31) (40.0,0.35)
    170 151 162 156 160
    1.00 0.93 0.19 0.83
    (0.0,0.00) (29.0,0.17) (52.0,0.43) (23.0,0.17)
    173 169 167 168
    1.00 0.23 0.93
    (0.0,0.00) (63.0,0.48) (27.0,0.17)
    358 174 179
    1.00 0.27
    (0.0,0.00) (44.0,0.41)
    177 173
    1.00
    (0.0, 0.00)
    181
    
    
    
    
    
    LEGEND
    R
    (P90, COD)
    N
    
    
    
    
    
    
    
    H
    0.24
    (25.0, 0.22)
    174
    0.32
    (48.0, 0.33)
    309
    0.34
    (27.0, 0.28)
    170
    0.11
    (38.0, 0.27)
    173
    0.26
    (46.0, 0.33)
    351
    0.73
    (28.0, 0.33)
    177
    0.27
    (30.0, 0.25)
    181
    1.00
    (0.0, 0.00)
    1060
    
    
    
    
    
    
    
    
    
    
    
    
    
    monitors reporting to AQS for
    i
    0.12
    (40.0, 0.39)
    173
    0.29
    (55.0, 0.49)
    302
    0.36
    (24.0, 0.30)
    168
    0.05
    (52.0, 0.46)
    172
    0.16
    (63.5,0.51)
    340
    0.32
    (27.0, 0.32)
    176
    0.20
    (46.5, 0.45)
    180
    0.26
    (27.0, 0.33)
    983
    1.00
    (0.0, 0.00)
    1015
    
    
    
    
    
    
    
    
    
    
    J
    0.83
    (38.5, 0.24)
    160
    0.13
    (51.0,0.25)
    172
    0.23
    (57.5, 0.41)
    150
    0.73
    (26.0,0.18)
    157
    0.86
    (18.0,0.13)
    175
    0.35
    (57.0, 0.46)
    162
    0.90
    (25.0,0.16)
    165
    0.47
    (45.0, 0.32)
    178
    0.20
    (62.0,0.51)
    177
    1.00
    (0.0, 0.00)
    178
    
    
    
    
    
    
    
    K
    0.27
    (30.0, 0.23)
    158
    0.31
    (49.0, 0.35)
    163
    0.38
    (24.0, 0.27)
    147
    0.13
    (43.0, 0.30)
    155
    0.27
    (54.0, 0.36)
    165
    0.43
    (24.5, 0.32)
    160
    0.35
    (34.0, 0.27)
    163
    0.48
    (18.0,0.18)
    172
    0.45
    (25.0, 0.32)
    172
    0.42
    (49.0, 0.35)
    155
    1.00
    (0.0,0.00)
    173
    
    
    
    
    
    0.46
    (32.0
    169
    0.35
    (51.0
    173
    0.50
    (30.0
    159
    0.38
    (40.0
    165
    0.57
    (40.0
    175
    0.44
    (35.0
    170
    0.58
    (29.0
    174
    0.40
    (29.0
    178
    0.38
    (41.0
    177
    0.70
    (37.0
    163
    0.49
    (30.0
    162
    1.00
    (0.0,
    178
    
    L
    
    , 0.25)
    
    
    ,0.31)
    
    
    , 0.25)
    
    
    , 0.26)
    
    
    , 0.28)
    
    
    , 0.35)
    
    
    , 0.24)
    
    
    , 0.25)
    
    
    , 0.39)
    
    
    , 0.27)
    
    
    , 0.26)
    
    
    0.00)
    
    
    M
    0.78
    (33.0,
    164
    0.29
    (44.0,
    168
    0.40
    (41 .0,
    154
    0.69
    (24.5,
    160
    0.82
    
    0.21)
    
    
    0.24)
    
    
    0.34)
    
    
    0.16)
    
    
    (26.0,0.15)
    171
    0.48
    
    
    (46.0, 0.43)
    164
    0.85
    (24.0,
    168
    0.44
    (34.0,
    175
    0.35
    (48.0,
    173
    0.85
    (20.0,
    157
    0.48
    (38.0,
    157
    0.84
    (24.0,
    167
    1.00
    
    
    0.15)
    
    
    0.26)
    
    
    0.46)
    
    
    0.15)
    
    
    0.29)
    
    
    0.20)
    
    
    (0.0, 0.00)
    175
    December 2009                                      A-204
    

    -------
        0.8
        0.6
      O
      O
        0.4
        0.2
                   10       20       30
                                             40       50       60
    
                                           Distance Between Samplers (km)
                                                                      70       80       90      100
    Figure A-120.  PM™ inter-sampler correlations as a function of distance between monitors for
                   Riverside, CA.
    December 2009
    A-205
    

    -------
                      Seattle Combined Statistical Area
            A
          01
                                             0 10 20   40
                        |	| Seattle CSA
                         •  PMio Monitors
                        	 Interstate Highways
                           - Major Highways
    
                     60   80   100
                     H^^^B^Z^ZI Kilometers
    Figure A-121.  PM™ monitor distribution and major highways, Seattle, WA.
    December 2009
    A-206
    

    -------
                       Site A  53-033-0057
                       SiteB  53-033-2004
    elD A B
    057 Mean 21.9 15.7
    004 Obs 1059 1077
    SD 9.9 8.6
    60 -
    50 -
    "g 40 -
    c
    ° 30 -
    ru
    C
    01
    Ł 20 -
    o
    u
    10 -
    1=winter
    2=spring
    3=summer g _
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Figure A-122.  Box plots illustrating the seasonal distribution of 24-h avg PMi0 concentrations
                  for Seattle, WA.
    Table A-48.  Inter-sampler correlation statistics for each pair of PMio monitors reporting to AQS for
                Seattle, WA.
    
    A
    
    
    B
    
    
    A
    1.00
    (0.0, 0.00)
    1059
    LEGEND
    R
    (P90, COD)
    B
    0.77
    (14.0,0.24)
    1041
    1.00
    (0.0, 0.00)
    1077
    N
    December 2009
    A-207
    

    -------
        0.8
        0.6
      O
      O
        0.4
        0.2
                   10        20       30       40       50       60
    
                                           Distance Between Samplers (km)
                                                                       70       80       90       100
    Figure A-123.  PM10 inter-sampler correlations as a function of distance between monitors for
                   Seattle, WA.
    December 2009
    A-208
    

    -------
                     St. Louis Combined Statistical Area
            A
          01
                             SLLouis CSA
                          •   PMio Monitors
                          	 Interstate Highways
                             Major Highways
                                       0  10  20    40    60     80
                               100
                               zzi Kilometers
    Figure A-124. PM™ monitor distribution and major highways, St. Louis, MO.
    December 2009
    A-209
    

    -------
            AQSSitelD
     Site A  17-117-0002
     SiteB  17-119-0010
     SiteC  17-119-3007
     SiteD  17-163-0010
     SiteE  29-189-5001
     SiteF  29-510-0085
     SiteG  29-510-0086
     SiteH  29-510-0087
     Site I   29-510-0088
                    en
                    c
                    o
                    c
                    cu
                    u
                    c
                    o
                    u
              1=winter
              2=spring
              3=summer
              4=fall
    A B C D E F G
    Mean 22.8 35.4 28.3 34.0 20.5 28.2 22.7
    Obs 171 173 174 176 185 176 179
    SD 9.4 15.5 12.2 14.7 14.4 11.7 10.4
    130 -
    120 -
    110 -
    100 -
    90 -
    80 -
    70 -
    60 -
    50 -
    40 -
    30 -
    20 -
    10 -
    0 -
    
    
    
    
    
    
    
    
    
    I I
    .!l
    '
    "
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    H
    29.5 40.3
    180 1050
    12.8 28.5
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                             1234   1234  1234   1234  1234   1234  1234   1234 1234
    Figure A-125.  Box plots illustrating the seasonal distribution of 24-h avg PM10 concentrations
                   for St. Louis, MO.
    December 2009
    A-210
    

    -------
    Table A-49.
    A
    A 1.00
    (0.0, 0.00)
    171
    B
    
    
    C
    
    
    D
    
    
    E
    
    
    F
    
    
    G
    
    
    H
    
    
    I
    Inter-sampler correlation
    St. Louis, MO.
    B C
    0.50 0.75 0.67
    (30.0,0.28) (14.0,0.17) (23.0
    161 158 156
    1.00 0.65 0.63
    (0.0,0.00) (20.0,0.21) (20.0
    173 161 158
    1.00 0.75
    (0.0,0.00) (17.0
    174 157
    1.00
    (0.0,
    176
    
    
    
    
    
    
    (P90 COD)
    N
    
    
    
    
    
    statistics for each
    D E
    0.47
    ,0.24) (16.0,0.29)
    158
    0.46
    ,0.19) (37.0,0.42)
    160
    0.57
    ,0.17) (23.0,0.33)
    158
    0.44
    0.00) (30.0, 0.40)
    157
    1.00
    (0.0, 0.00)
    185
    
    
    
    
    
    
    
    
    
    
    pair of PMio
    F
    0.65
    (16.0,0.18)
    163
    0.68
    (23.0, 0.20)
    167
    0.80
    (12.0,0.13)
    165
    0.82
    (16.0,0.15)
    163
    0.53
    (22.0, 0.34)
    164
    1.00
    (0.0, 0.00)
    176
    
    
    
    
    
    
    
    monitors
    G
    0.67
    (13.0,0.17)
    166
    0.68
    (28.0, 0.28)
    169
    0.76
    (13.0,0.18)
    169
    0.81
    (21.0,0.24)
    165
    0.62
    (17.0,0.26)
    166
    0.89
    (11.0,0.16)
    173
    1.00
    (0.0, 0.00)
    179
    
    
    
    
    reporting
    H
    0.73
    (18.0,0.19)
    168
    0.64
    (22.0, 0.20)
    170
    0.82
    (12.0,0.13)
    169
    0.80
    (14.0,0.15)
    166
    0.56
    (25.0, 0.35)
    167
    0.86
    (12.0,0.11)
    174
    0.83
    (16.0,0.19)
    177
    1.00
    (0.0, 0.00)
    180
    
    to AQS for
    i
    0.55
    (52.0, 0.33)
    164
    0.52
    (36.0, 0.28)
    166
    0.65
    (41.0,0.27)
    168
    0.59
    (36.0, 0.27)
    169
    0.34
    (55.0, 0.42)
    179
    0.67
    (41.0,0.27)
    169
    0.65
    (47.0, 0.32)
    173
    0.64
    (41.0,0.27)
    173
    1.00
    (0.0, 0.00)
    1050
    December 2009                                       A-211
    

    -------
        0.8
        0.6
      o
      13
      oi
      5
      o
        0.4
        0.2
                   10        20       30       40       50       60       70
                                           Distance Between Samplers (km)
                                                                               80
                                                                                       90
                                                                                                100
    Figure A-126.  PM10 inter-sampler correlations as a function of distance between monitors for St.
                   Louis, MO.
    Table A-50.   Correlation coefficients of hourly and daily average particle number, surface and volume
                 concentrations in selected particle size ranges.
    Size range
    (nm)
    3-10
    10-30
    30-50
    50-100
    100-500
    500-800
    10-100
    10-800
    Total number
    Total surface
    Total volume
    Hourly averages
    All days (N = 5481)
    0.40
    0.35
    0.38
    0.46
    0.55
    0.73
    0.31
    0.55
    0.30
    0.57
    0.66
    Sundays (N = 701)
    0.24
    0.22
    0.42
    0.56
    0.65
    0.75
    0.28
    0.65
    0.24
    0.63
    0.69
    Weekdays (N = 3227)
    0.42
    0.31
    0.29
    0.39
    0.49
    0.70
    0.24
    0.49
    0.24
    0.51
    0.62
    Event days (N = 577)
    0.73
    0.57
    0.56
    0.57
    0.62
    0.76
    0.52
    0.62
    0.58
    0.65
    0.73
    No events (N
    0.37
    0.33
    0.36
    0.45
    0.55
    0.72
    0.29
    0.55
    0.28
    0.56
    0.65
    Daily avg
    = 4904) All days (N
    0.32
    0.27
    0.36
    0.46
    0.55
    0.71
    0.24
    0.55
    0.20
    0.57
    0.67
    = 263)
    
    
    
    
    
    
    
    
    
    
    
    Source: Tuch et al. (2006)
    December 2009
    A-212
    

    -------
    A.2.3. Speciation
                                  Atlanta, GA
               Atlanta, GA
                               tOJS :f? atioti • Spnno
          Atlanta, GA
                                                                       FRW PM 2 S apsciatiftn • Sunimei
               Atlanta, GA
                                                        1=1 OCM ^H Crustal
                                                         SANDWICH sulfate am
                                                         Atlanta. GA
                                                         =Z1 Sullate "^ Ntt
    
                                                         =) OCM ^
                                                         SflNOWlCH sulftte and nltralo rclud
    Figure A-127.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                   c) summer, d) fall and e) winter derived using the SANDWICH method in Atlanta,
                   GA.
    December 2009
    A-213
    

    -------
                                   Birmingham, AL   FRMPII,25
                                    (=1 Sutfate ^H Nitrate ^H E>
    
                                    i	1 COM  ^H Crustal
                                    SANDWICH sutfate and iWratelndiMe ammonium and
         Birmingham, AL
                            FRMPW2.S special  Spring
             Birmingham, AL
                                                                                           :ia!ion • Summer
          SANDWICH stifateafid niraie inciude ammoniim srtd
                                                                  i	1 OCM  ^H Crustal
                                                                   SANDWICH sutfate and nitrate Include ammonium and
         Birmingham, AL
          SANDWICH stjf.-,te .-,rvj mt-.re IT uae
             Birmingham, AL
                                                                                     FRM PWiSsnee.aliort • W
                                                                   SANDWICH sul&te »r\a rflrit* Include irnmonlum sna
    Figure A-128.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                     c) summer, d) fall and e) winter derived using the SANDWICH method in
                     Birmingham, AL.
    December 2009
    A-214
    

    -------
                                           Boston, MA/NH   FRMPM25spsciaBon-<-Se9SO"Avg
                                          I   1 Sulfate ^H Nitrate
                                          i	1 OCM  VHl Crustal
                                           SANDWICH sulfale and nitrate
            Boston, MA/NH
                              FRMPM25 specatlon - Spring
    [=1 Sulfate ^M Nitrate ^H EC
    i	1 OCM mmm Crustal
     SANDWICH Sulfate and ntr;
                                                                   Boston, MA/NH
                                                                                            FRM PMiSspecialton - J
                                                                          SANDWICH sulfate ai
                                                                           ] Sulfate ^H Nitrate ^^ EC
                                                                           ] OCM  ^H Crustal
                                                                                           inium and wsler
            Boston, MA/NH    FB"P"'-S"••"""-T-M
           i   i Sulfate I^B Nitrate •
           i	1 OCM  I^B Crustal
            SANDWICH suifate and ntrate include
                                                                   Boston, MA/NH
                                                                  I   I Sulfate ^^ Nitrate •
                                                                  i	1 OCM  ^H Crustal
                                                                   SANDWICH sulfate and nitrate include ammonium and
    Figure A-129.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                      c) summer, d) fall and e) winter derived using the SANDWICH  method  in  Boston,
                      MA.
    December 2009
                                                     A-215
    

    -------
                                        Chicago, IL/IN
                                                          FRM PM2.5spetiaiion - <-Season A
              Chicago, IL/IN
                                 FR*IPM2.5!psciirtkin - Spring
                  IL/IN
                - Sulfate ••• itiate
    
                J OCM ••• CrusEal
               SAPJDWICH iiirale anU rirate include amrronium and wsla
          [  3 Suifaie ••• itrae B^H EC
    
          '	1 OCM ••• Crui al
           SANDWICH sulfaie aril nlfate include atnrwtKum and
              Chicago, IL/IN
                                 FRM PM2.5 spenaion - T_Faii
          Chicago, IL/IN
                                                                                    FRMPM25speciallon - Winter
              i	1 OCM ••• Crustal
               SANDWICH sJfate
          1=1 Sulfate ••• Nitrate •"• EC
    
          i	1 OCM ••• Crus al
           SANDWICH sulfale anfl nitrate"IncludT
    Figure A-130.  Seasonally averaged  PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                      c) summer, d) fall and e) winter derived using the SANDWICH method in  Chicago,
                      IL
    December 2009
    A-216
    

    -------
                                      Denver, CO
                                       i Sulfate ^™ Nitt
                                     i - 1 OCM
                                      SSNDWICH sul
                    Deliver. CO      FHMPMJ 5 gpaclaticr -sprng
                                                          Denver, CO
    ^ Sulfate ^™ Nitra
    D OCM MM Cms
                                ./
                                 /
                    SANDWICH sjlftte and nilrae include smrtioniiim
                                                                         (5
                                                         i	1 OCM  ^m Crustal
                                                         SANDWICH sulfae snii itlt'f.e inr luoe ^r
                          CO      FRM PM2.S speciatio-- T_Fatl
                                                          Denver, CO
                                   (5
                               ~?
    Figure A-131.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                   c) summer, d) fall and e) winter, derived using the SANDWICH method in Denver,
                   CO.
    December 2009
                                   A-217
    

    -------
                                                     it, M I
                                                                 FRO! PM2 Sspeelation - 4-SeasBfiAvg
                                                   i. -Kte ^H Nitrate ••
    
                                                   CM  ^« Crustal
                                                   H sullate and niraie mciuae ammonium and
                Detroit, Ml
                                   FRMPMJSspeciaiiwi • S
            Detroit. M I
                                                                                         FRM PHlSwwtttan - Summer
                 1 Sulfate
    
                 J OCM
                           usu
                  1-"'1!. h iiC.^I'- vnli.:t^|Mi'iili.,i- HI, • if.rniir.1 AIO
              1 Sulfate ^^ Nitrate
    
              1 OCM  ^m Crusta
              Cft'WCH suitale ana ntraie ncTirie amnomum and
                Detroit, Ml
                 1 Sulfate ^™ Nitrate
    
               l	1 OCM  ^H CrusUt
                SANDWd>i suliate arm nitiate mrlnrff* sir^innwrn and Walw"
            Detroit, Ml
              I Sulfate ^^ Nitrate •• EC
    
              1 OCM  <^m CrusUI
              DWCH suiraie ana mtrase nciuie annmoniji-n
    Figure A-132.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                      c) summer, d) fall and e) winter derived using the SANDWICH method in Detroit,
                      Ml.
    December 2009
    A-218
    

    -------
                                     HOUStOn,  I A.     FRM PM!-5speciatJor) - 4-SeasOR
                                       : ._-,:;.!-M: •• '•! r:o: ^H EC
    
                                       : OCM  •• Crustal
                                     :!..--M>/'
    -------
                                  Los Angeles, CA
                                  I  I Sutfate •• Nitrate ^
    
                                  E	1 OCM  ^H Crustal
                                  SANDWICH suiraie and nrr/aie nclude
          LOS
        Los Angeles, CA
          r	1 Sulfate •• Kitrate
    
          i	1 OCM ^m Crustal
           SANDWICH ajlfaie and ni
        I  I Sulfate •• I ii -?,r= ^B EC
    
        i	1 OCM  ^m Crustal
         SANDWICH sullaie and nitrate Hi
          Los Angeles, CA
        Los Angeles, CA
          I	1 Sulfate ^H Wrate ^B EC
    
          I	1 OCM ^m Crustil
           SAIJDWICH stilus arid rierat
        I  I Sulfate ^H N^rate ^^ EC
    
        I	1 OCM  ^M Crujtal
         SANOWICK iulrale dlid rnuale include
    Figure A-134.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                     c) summer, d) fall and e) winter derived using the SANDWICH method in Los
                     Angeles, CA.
    December 2009
    A-220
    

    -------
                                   New York, NY/NJ/OT" «>!„».-«. -«—,»,
                                                                     G
                                   '	' OCM ^H Criwtal
    
                                    SANDWICH sfclfale anil mlrsle m'uc
      New York. NY/NJ/CT"«p»»»«=«•» -**»
         New York, NY/NJ/CT™«"«
                                       G
     !=l OCM ^» Crustal
      SANDWICH aJfateani] nirale incude anrmDnum ang w
          = OCM  ^H Crustal
          m-IDWICH sulfate and n.liale nouae atr
    -------
                                  Philadelphia,
                                  i	1 OCM  IHI Cruttil
                                  SANDWICH sulfaie and niliale hciude ai
                                                  wrium and water
     Philadelphia, PA/NJ FRMP«.SM«M«,-SP«,
          Philadelphia, PA/NJ FR""is
                                                                  OCM  i^H Crustal
                                                                     Hatr am: r.-;i3ie hi-h.de a
                                                                               nomum antjv&tet
     Philadelphia, PA/NJ
          Philadelphia, PA/NJ FRM«»»««
      =i OCM  ^^ Crustal
      3AMDWICH sJlateandiMirateirxiudearwroriurn snd w
          i	1 OCM  ^M Crustal
           SANDWICH sunaie and rnnie hciLdeancemum and water
    Figure A-136.  Seasonally averaged  PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                     c) summer, d) fall and e) winter derived using the SANDWICH method in
                     Philadelphia, PA.
    December 2009
    A-222
    

    -------
                                          Phoenix, AZ
                                           3 •  i.-,r- H*i Mr MI-- I^B EC
    
                                           •J OCM I^H Coital
                                    Q    Q
                                          •:.-. '[.'••!: I - .l-a:e a vj Hr.li: in; j'Jo -.iti,-r nnjm
          Phoenix, AZ
                            FRtf PM2.5 spscBtlcn • Spi
    : S fate ^Hl Nitrate  ^B EC
    
    : OCM  ^M Crystal
                                  Q    Q
                                     Phoenix, AZ
                 ---' .-.-..1 nr-.v.-- i-.-i i-r -i-riir»-,-iiini wtd water
    MBS
    
    C=I1 O
    
     :>'l,i|),\ni; 11 r.iili.itr- -,rri riltir.- ]-iiijrt:- vTrinii i-- .-inr ,,,-j-.--
                                         ti:f- "• 'iiti -,;:- ^^ EC
    
                                            ^^ CrysUI
    Q
          Phoenix, AZ
            S fate W Nitrate I^M EC
    
            OCM •• Crustsl
    Q    Q
              ' fulnre a-nJ nr-.^e ITI j-je iJtirmvujrn and \v3lei
                                     Phoenix, AZ
                                                                       Itate ^B> Nitrate ^^ EC
                                                                       M  ^^ Crystal
    Q    Q
                                                                     v^i: 11 s.,if,Htf an.! mraie nciude anroortum .-1,1,7 >
    Figure A-137.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                      c) summer, d) fall and e) winter derived using the SANDWICH method in Phoenix,
                      AZ.
    December 2009
                              A-223
    

    -------
                                 Pittsburgh, PA
       Pittsburgh, PA
         Pittsburgh, PA    FRHPUi$wecai&> - Summer
                                                         - OCM  ^H Crustal
    
                                                         iNDWICH Su1
                                                                 rata ntujde arnrnortiim anflwatei
       Pittsburgh, PA
         Pittsburgh, PA
                  lude airmurijum and wiw
                                                       i	1 OCM
    
                                                        SANDWICH Su
    Figure A-138.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                   c) summer, d) fall and e) winter derived using the SANDWICH method in
                   Pittsburgh, PA.
    December 2009
    A-224
    

    -------
                                          Riverside, CA
                                        I	i Sulfate ^H Nitrate
    
                                        i	1 OCM  ^m Crustal
                                         SANDWICH sullate and rntrale TIC'L
                Riverside, CA
                                  FRK PW2.Sspeca1mn - Spring
          Riverside, CA
               I	i Sulfate ^K Nitrate "• EC
    
               t	1 OCM  ^^ Crusts!
                SANDWICH sulfate and nlrale include ammonium aid water
         I	1 Sulfate ••§ Nitrate ••• EC
    
         i	1 OCM i^m Crustal
          SANDWICH suKale and rilrste rc-lude
                Riverside, CA      rmfl»ji^Mn.-,J
          Riverside, CA      FRI
    -------
                                     Seattle, WA
                                                     FRM PM2 5speaati«m - 4-SeasanAvg
                                    I	1 OCM  ^Bl Crystal
                                    SANDWICH sutfst? a-id -iviie r.ci j:ie anminjum and
                   Seattle, WA
                    J Sulfate ^^ l'J:!(.rc
    
                    : OCM  ^M Crustal
           Seattle, WA
                                                                                    FRKPM 2 5 specimen - Summei
                   >JvNr.'i.'V'l[-H = 'fit- i-,, rii'V- .:-,-! jrifismmopwm Ud w
            1 Suifate ^^ Nitrate
    
            1 OCM ^M Crustal
                                                                  SANDWICH SUHateanOrJIrateiiflule ammonium and
                                                                  Seattle, WA
                                                                                    FRM PUŁ5speciaiion - Wnti
                                                                 i  > Sulfats ^^f Nitrate
    
                                                                 i	1 OCM ^^ Crustal
                                                                  3AND\^ICHsuHa» ana pirate ntluaearmwrtum and water
    Figure A-140.   Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                      c) summer, d) fall and e) winter derived using the SANDWICH method in Seattle,
                      WA.
    December  2009
    A-226
    

    -------
                                St. Louis, MO/IL
    ^ Sulfate
    
    =1 OCM
    
    SANDWICH sul
                                         i Nitrate ^H EC
                                           •ustal
    V   J\f   N\
    !^OX
             St. Louis, MO/IL
                                                           St. Louis, MO/IL
               'T tulfatc ^^M Nil'
    
               1 OCM  •• Crustal
                   jfale and nitrate include ammnnurn anij wattt
             St. Louis, MO/IL
             I  I Sutfate ^B Mitral ^^ EC
    
             [	! OCM  ^H Crus al
              Sftr«W1CH Sul^lt an-: Mliile uu.ljUy r,rin:i.(:ij[[i
                                                           St. Louis, MO/IL    FRMPW25
                                                                                 spetiabon - Winter
    Figure A-141.  Seasonally averaged PM2.s speciation data for 2005-2007 for a) annual, b) spring,
                    c) summer, d) fall and e) winter derived using the SANDWICH method in St. Louis,
                    MO.
    December 2009
                         A-227
    

    -------
    Figure A-142. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Atlanta, GA, 2005-2007. The gray line represents the difference in OCM
                 calculated using material balance and blank corrected OCx1.4.
    Figure A-143. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Birmingham, AL, 2005-2007. The gray line represents the difference in
                 OCM calculated using material balance and blank corrected OCx1.4.
    December 2009
    A-228
    

    -------
                                   E 20-1
                                   a
                                       1254567
    Figure A-144. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Boston, MA, 2005-2007. The gray line represents the difference in OCM
                 calculated using material balance and blank corrected OCx1.4.
    Figure A-145. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Chicago,  IL, 2005-2007. The gray line represents the difference in OCM
                 calculated using material balance and blank corrected OCx1.4.
    December 2009
    A-229
    

    -------
    Figure A-146. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Denver, CO, 2005-2007. The gray line represents the difference in OCM
                 calculated using material balance and blank corrected OCx1.4.
    Figure A-147. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Detroit, Ml, 2005-2007. The gray line represents the difference in OCM
                 calculated using material balance and blank corrected OC x 1.4.
    December 2009
    A-230
    

    -------
    Figure A-148. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Houston, TX, 2005-2007. The gray line represents the difference in
                 OCM calculated using material balance and blank corrected OCx1.4.
    Figure A-149. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Los Angeles, CA, 2005-2007. The gray line represents the difference in
                 OCM calculated using material balance and blank corrected OCx1.4.
    December 2009
    A-231
    

    -------
    Figure A-150. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for New York, NY, 2005-2007. The gray line represents the difference in
                 OCM calculated using material balance and blank corrected OCx1.4.
    Figure A-151. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Philadelphia, PA, 2005-2007. The gray line represents the difference in
                 OCM calculated using material balance and blank corrected OCx1.4.
    December 2009
    A-232
    

    -------
    Figure A-152. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Phoenix, AZ, 2005-2007. The gray line represents the difference in OCM
                 calculated using material balance and blank corrected OCx1.4.
    Figure A-153. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Pittsburgh, PA, 2005-2007. The gray line represents the difference in
                 OCM calculated using material balance and blank corrected OCx1.4.
    December 2009
    A-233
    

    -------
    Figure A-154. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Riverside, CA, 2005-2007. The gray line represents the difference in
                 OCM calculated using material balance and blank corrected OCx1.4.
                                   "Ł 20-
                                   a
    Figure A-155. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for Seattle, WA, 2005-2007. The gray line represents the difference in OCM
                 calculated using material balance and blank corrected OCx1.4.
    December 2009
    A-234
    

    -------
                                       1254567
    Figure A-156. Seasonal patterns in PM2.s chemical composition from city-wide monthly average
                 values for St. Louis, MO, 2005-2007. The gray line represents the difference in
                 OCM calculated using material balance and blank corrected OCx1.4.
    
    
    A.2.4. Diel Trends
      in
      c\i
         77 n
         58 -
         38 -
          19 -
                 Weekday (N = 5156)
    77 -,
    
    
    58 -
    
    
    38 -
    
    
    19 -
                        12     18     24
                                             0
           Weekend (N = 2086)
                                                                                 • Median
                       	Mean
    
                       	90'th&10'th
    
                       	95'th & 5'th
       1
    12     18     24
    Figure A-157.  Diel plots generated from all available hourly FRM-like PM2.s data, stratified by
                  weekday (left) and weekend (right), in Atlanta, GA. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
      A-235
    

    -------
                 Weekday(N =1975)
                                 Weekend (N = 797)
      c\
    77 -,
    58 -
    38 -
    19 -
    
    0 -i
    
    
    
    
    	 	
    6 12 18 2<
                        77 -,
    
    
                        58 -
    
    
                        38
    
    
                        19
                                                                                  •Median
                                    	Mean
    
                                    	90'th & 10'th
    
                                    •••••• 95'th & 5'th
                                                           12     18    24
    Figure A-158.  Diel plots generated from all available hourly FRM-like PM2.s data, stratified by
                  weekday (left) and weekend (right), in Chicago, IL. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
     c\
         77 -i
         58 -
         38 -
         19 -
                Weekday (N = 7032)
                        77 -i
    
    
                        58 -
    
    
                        38 -
    
    
                        19 -
                                Weekend(N = 2854)
                                                                                   •Median
                                    	Mean
    
                                    	90'th&10'th
    
                                    ••••••  95'th & 5'th
            1
    12     18    24
    1
    12     18    24
    Figure A-159.  Diel plots generated from all available hourly FRM-like PM2.s data, stratified by
                  weekday (left) and weekend (right), in Houston, TX. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
                           A-236
    

    -------
                 Weekday(N = 3348)
      up
      cxi
          77 i
          58 -
          38 -
          19 -
    77 -,
    
    
    58 -
    
    
    38
    
    
    19
                         12     18     24
                                             0
            Weekend (N = 1364)
                                                                                   • Median
    	Mean
    
    	90'th & 10'th
    
    •••••• 95'th & 5'th
                   12     18     24
    Figure A-160.  Diel plots generated from all available hourly FRM-like PM2.s data, stratified by
                  weekday (left) and weekend (right), in New York, NY. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
      in
      csi
          77 T-
          58 -
          38 -j
          19 -j
                  Weekday(N =981)
                         12     18     24
            Weekend (N = 407)
    77 ->
    58 -
    38 -j
    19 -j
                   12     18     24
                                                                                   • Median
    	Mean
    
    	90'th & 10'th
    
    ••-••• 95'th & 5'th
    Figure A-161.  Diel plots generated from all available hourly FRM-like PM2.s data, stratified by
                  weekday (left) and weekend (right), in Pittsburgh, PA. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
      A-237
    

    -------
                 Weekday(N = 5775)
    
    un
    CN
    >
    Q_
    
    
    / / -
    58 -
    
    
    38 -
    
    19 -
    0 -I
    
    
    
    
    
    •-".." I'"- ----':;_• •.,.••;,"---
    
                                            77 -j
    
    
                                            58 -
    
    
                                            38
    
    
                                            19
                         12     18     24
                                             0
                  Weekend(N = 2332)
                                                 • Median
                                             	Mean
    
                                             	90'th&10'th
    
                                             •••••• 95'th & 5'th
                          12     18     24
    Figure A-162.  Diel plots generated from all available hourly FRM-like PM2.s data, stratified by
                  weekday (left) and weekend (right), in Seattle, WA. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th  percentiles for
                  each hour.
      un
      CN
          77 n
          58 -
          38 -
          19 -
                 Weekday(N =1727)
                        12     18
    24
          77 -j
    
    
          58 -
    
    
          38 -
    
    
          19 -
                                             0
    1
                  Weekend (N = 692)
                                                                                  • Median
                                   	Mean
    
                                   	90'th&10'th
    
                                   •••••• 95'th & 5'th
    12     18
    24
    Figure A-163.  Diel plots generated from all available hourly FRM-like PM2.s data, stratified by
                  weekday (left) and weekend (right), in St. Louis, MO. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
             A-238
    

    -------
                 Weekday (N = 715)
    218 -
    145 -
         73 -
                        12     18     24
                                                Weekend (N = 293)
                218 -
    
    
                145 i
    
    
                 73 ^
                    1
                                                       12     18     24
                                                                                  •Median
                                                                              	Mean
    
                                                                              	90'th & 10'th
    
                                                                              •••••• 95'th & 5'th
    Figure A-164.  Diel plot generated from all available hourly FRM/FEM PMi0 data, stratified by
                  weekday (left) and weekend (right), in Atlanta, GA. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    218 -
    145 -
         73 -
            1
                 Weekday(N =1971)
    12
    18
                                 24
                218 -
    
    
                145 -
    
    
                 73 -
                                            Q
    1
                                                Weekend (N = 793)
                                                                                 • Median
                                                                              	Mean
    
                                                                              	90'th & 10'th
    
                                                                              •••••• 95'th & 5'th
    12
    18
    24
    Figure A-165.  Diel plot generated from all available hourly FRM/FEM PMi0 data, stratified by
                  weekday (left) and weekend (right), in Chicago, IL. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
                                          A-239
    

    -------
                Weekday (N = 1310)
        291 i
        218 -
        145
         73 -
                                               Weekend (N = 529)
                                      291 i
                                      218 -
                                      145
                                       73 -
                        12     18     24
                                                                                 • Median
                                       	Mean
    
                                       	90'th & 10'th
    
                                       	95'th & 5'th
                                                      12     18    24
    Figure A-166. Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by
                 weekday (left) and weekend (right), in Denver, CO. Included are the number of
                 monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                 each hour.
        291 n
    218
    145 -
         73 -
                 Weekday (N = 756)
            1
    12     18
                                 24
    291 n
    
    
    218
    
    
    145 -
    
    
     73 -
        1
                                               Weekend (N = 302)
                                                                                  •Median
                                                                              	Mean
    
                                                                              	90'th & 10'th
    
                                                                              	95'th & 5'th
    12     18
    24
    Figure A-167. Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by
                 weekday (left) and weekend (right), in Detroit, Ml. Included are the  number of
                 monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                 each hour.
    December 2009
                                          A-240
    

    -------
                 Weekday(N = 692)
                   Weekend (N = 277)
    218 -
    145 -
    73 -
    
    0 -I
    218 -
    145 -
    ;'**'-. ... 73 "
    _ - — i^*1^ ^**-^ ' ^ i - -• • g ' ~"* w ' • •_
    r"'""i 	 ""i'"-'""r; i ••••"•"•• i o -1
    
    
    
    	 	
    
                                                                                  • Median
                                                                              	Mean
    
                                                                              	90'th&10'th
    
                                                                              ••••••  95'th & 5'th
                        12     18     24
                         12     18     24
    Figure A-168.  Diel plot generated from all available hourly FRM/FEM PMi0 data, stratified by
                  weekday (left) and weekend (right), in Los Angeles, CA. Included are the number
                  of monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
        291 n
        218 -
        145 -
         73 -
                 Weekday (N = 742)
                        12     18
    24
         291 -j
    
    
         218 -
    
    
         145 -
    
    
          73 -
                                             0
    1
                  Weekend (N = 303)
    12     18
    24
                                                                                  • Median
                                   	Mean
    
                                   	90'th&10'th
    
                                   -••••• 95'th & 5'th
    Figure A-169.  Diel plot generated from all available hourly FRM/FEM PMi0 data, stratified by
                  weekday (left) and weekend (right), in Philadelphia, PA. Included are the number
                  of monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
             A-241
    

    -------
                 Weekday(N =1532)
                         Weekend (N = 618)
        291 ->
        218 -
        145 -
         73 -
                291 ->
                218 -
                145 -
                        12
    18     24
                 73 -
                                                                                  • Median
                       	Mean
    
                       	90'th&10'th
    
                       ••-••• 95'th & 5'th
    12
    18    24
    Figure A-170.  Diel plot generated from all available hourly FRM/FEM PM10 data, stratified by
                  weekday (left) and weekend (right), in Phoenix, AZ. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
                 Weekday (N = 6385)
                        Weekend (N = 2600)
    /ia i -
    218 -
    145 -
    73 -
    
    U \
    /ja i -
    218 -
    145 -
    •••••••••'„'-'',;••. ..... 73 -
    	 *• " ^ x ^' • • • • 	 '•_" 	
    
    ••"•""P 	 '^r— 	 1 	 ^ o -i
    
    
    
    	 	
    F — - — i 	 '" "i"" 	 1 	 1
                                                                                  • Median
                                                                              	Mean
    
                                                                              	90th&10'th
    
                                                                              ••-•-• 95'th & 5'th
                        12     18    24
                                12    18     24
    Figure A-171.  Diel plot generated from all available hourly FRM/FEM PMi0 data, stratified by
                  weekday (left) and weekend (right), in Pittsburgh, PA. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
                   A-242
    

    -------
                 Weekday (N = 1660)
        291 ->
        218 -
         145
         73 -
          0 -P
                         Weekend (N = 673)
                291 i
                218
                145
                 73 -
                                                                                 • Median
                                                          	Mean
    
                                                          	90'th&10'th
    
                                                          •••••- 95th & 5th
                        12     18    24
                           16      12     18
                                             24
    Figure A-172.  Diel plot generated from all available hourly FRM/FEM PMi0 data, stratified by
                  weekday (left) and weekend (right), in Riverside, CA. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
        291  -,
        218 -
        145 -
         73 -
                 Weekday(N = 752)
            1
                         Weekend(N = 309)
                       218 -i
    
    
                       145 -
    
    
                        73 -
    12
    18    24
                                            0
    1
    12     18
    24
                                                                                  • Median
                                                   	Mean
    
                                                   	90'th & 10th
    
                                                   •••••• 95th & 5th
    Figure A-173.  Diel plot generated from all available hourly FRM/FEM PMi0 data, stratified by
                  weekday (left) and weekend (right), in Seattle, WA. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
                   A-243
    

    -------
                 Weekday(N =1741)
          Weekend (N = 706)
        291 ->
        218 -
        145 -
         73 -  ---•
                        12     18     24
    291 -I
    218 -
    145 -
    73 -
    
    
    0 -I
    
    
    
    
    ^
    
    
                                                                                  • Median
                                    	Mean
    
                                    	90'th&10'th
    
                                    ••-••• 95'th & 5'th
                 12     18     24
    Figure A-174.  Diel plot generated from all available hourly FRM/FEM PMi0 data, stratified by
                  weekday (left) and weekend (right), in St. Louis, MO. Included are the number of
                  monitor days (N) and the median, mean, 5th, 10th, 90th and 95th percentiles for
                  each hour.
    December 2009
    A-244
    

    -------
    A.2.5. Copollutant Measurements
                            Winter
                                                                 Spring
    PM10 (daity avg).
    PM10-2.5 (daity avg).
    SO2 (daiV avg)-
    NO2 (daiV avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    
    
    oo
    o
    
    oo
    o o
    
    
    
    
    
    
    
    
    
    O O
    O
    
    O O
    O O
    ooo
    ^ ^ Q°> ^ Ł <$> Q-i <$> & ^
    Summer Fall
    PM10 (daiV avg)-
    PM10-2.5 (daiV avg).
    SO2 (daity avg)-
    NO2 (daity avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    (
    
    
    c
    
    o o
    )
    
    o
    o
    <32>
    
    O
    
    
    
    
    o
    
    
    o o
    o o
    ooo
    Figure A-175.  Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg 03 for Atlanta, GA, stratified by season (2005-
                 2007). One point is included for each available monitor pair.
    December 2009
    A-245
    

    -------
                             Winter
                                                                    Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    c
    ©
    
    
    
    
    )
    Summer
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    GD
    
    
    
    
    
    -------
                                 Winter
                                                                              Spring
       PM10 (daily avg)'
    
    
     PM10-2.5 (daily avg)-
    
    
       SO2 (daily av<
    
    
       NO2 (daily avg)-
    
    
        CO (daily avg)'
    
    
      O3 (daily max 8-hr)'
    
     OO OO
    oasis)
    O(D>
    
    
    
    
    
    
    
    QGS)
    O
    C2DOOO
    OOOD
    OO O
    OQOO
       PM10 (daily avg)'
    
    
     PM10-2.5 (daily avg)-
    
    
       SO2 (daily avg)'
    
    
       NO2 (daily avg)<
    
    
        CO (daily avg)<
    
    
      O3 (daily max 8-hr)'
                                Summer
                                                                               Fall
    
    (
    O C
    
    O(
    
    am
    ) O
    >ODO O
    CX3D>O
    X) O
    OQ)
    
    
    (
    
    
    
    (330
    (D)
    )<0> OO
    O®
    OO O
    OO OS) O
    Figure A-177.  Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                    and CO and daily maximum 8-h avg 03 for Boston, MA, stratified by season
                    (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-247
    

    -------
                               Winter
                                                                          Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    O
    
    
    
    O CD
    O Q88HD
    
    OO
    OOO
    O
    
    
    
    
    O
    
    
    O (2XSE)
    O
    (D) O
    00 O
    OO
    OOKDO O
       PM10 (daily avg)'
    
    
     PM10-2.5 (daily avg)-
    
    
       SO2 (daily avg)'
    
    
       NO2 (daily avg)<
    
    
        CO (daily avg)<
    
    
     O3 (daily max 8-hr)'
                               Summer
                                                                          Fall
    
    
    i
    
    
    
    OTE
    O
    D OO
    OO 000
    OO
    (J3GDO
    
    O
    (
    O
    
    
    OOODO
    
    ) O OO
    (DO
    OO
    OHD ooo
    Figure A-178.  Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                   and CO and daily maximum 8-h avg 03 for Chicago, IL, stratified by season (2005-
                   2007). One point is included for each available monitor pair.
    December 2009
    A-248
    

    -------
                             Winter
                                                                    Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o
    am)
    o
    o
    o
    o
    
    Summer
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    (SD>
    o
    o
    o
    o
    D
    
    
    
    
    
    o
    Fall
    
    
    
    
    
    O
    <0)GD
    O
    O
    O
    O
    
    
    
    -------
                             Winter
                                                                     Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o
    oo
    
    ooo
    o
    oo
    
    Summer
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    oo
    
    G2D OO
    OO
    O O®
    G08D
    
    
    
    
    
    (
    Fall
    
    
    
    
    
    
    O OO
    
    ooo o
    GD
    OOO
    )O OCE»OD
    
    OO
    
    (M»
    O O
    OOO
    0 GOBDO
    Figure A-180.  Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                  and CO and daily maximum 8-h avg Osfor Detroit, Ml, stratified by season
                  (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-250
    

    -------
                             Winter
                                                                    Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o
    o
    
    o
    o
    o
    
    Summer
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    o
    
    o
    
    o
    o
    
    o
    
    
    I
    c
    
    I
    Fall
    
    
    
    
    
    
    o
    
    D
    )
    o
    D
    
    O
    
    O
    O
    O
    O
    Figure A-181. Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg 03 for Houston, TX, stratified by season
                 (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-251
    

    -------
                               Winter
                                                                         Spring
       PM10 (daily avg)'
    
    
     PM10-2.5 (daily avg)-
    
    
       SO2 (daily av<
    
    
       NO2 (daily avg)-
    
    
        CO (daily avg)'
    
    
     O3 (daily max 8-hr>
    
    
    
    GOOGE)
    o am
    OD O
    vUUL)
    ODD GO
    
    
    1
    c
    
    ooooo
    D O O
    X03OODOO
    mo a
                               Summer
                                                                          Fall
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    O OD O
    
    GO)
    GGBQO
    SSEBE)
    GDOCDCD
    
    
    (
    
    o oo  a
    OOQDO) O
    Figure A-182.  Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                   and CO and daily maximum 8-h avg 03 for Los Angeles, CA, stratified by season
                   (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-252
    

    -------
                               Winter
                                                                          Spring
       PM10 (daily avg)'
    
    
     PM10-2.5 (daily avg)-
    
    
       SO2 (daily av<
    
    
       NO2 (daily avg)-
    
    
        CO (daily avg)'
    
    
     O3 (daily max 8-hr>
    
    
    
    
    
    
    OO O
    
    
    
    
    
    
    OO
    000
    OO
    GfflBBO
    OOGDO
    OQD
    CD O3D
                               Summer
                                                                          Fall
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    (5
    
    
    
    
    GOO
    )
    030OQD)
    O OdD
    OO OOO
    
    -------
                             Winter
                                                                     Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    <3SD
    OB2)
    
    OODO
    (23Q>
    OOSKD
    
    Summer
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    O (
    
    (SOO
    
    OD OODO
    OOOO O
    3 (O>
    (3HQD
    
    
    
    
    O
    
    Fall
    
    
    
    
    
    
    GO
    
    QfloxjoQaju
    (OS3D
    OOOO
    O ©OO
    
    00)
    
    CX3OD
    OS3D
    (33$) O
    (OD» 02DO(D)
    Figure A-184.  Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                  and CO and daily maximum 8-h avg Os for Philadelphia, PA, stratified by season
                  (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-254
    

    -------
                             Winter
                                                                    Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    OS)
    <3EO
    O
    O
    3D
    OO
    
    Summer
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    O ®OO
    O
    O
    OO
    OO
    GO
    
    
    
    
    
    
    Fall
    
    
    
    
    
    ooo
    O OO
    O
    O
    OO
    ooo
    OGD
    
    O GO)
    O
    O
    O
    OO
    
    Figure A-185. Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg 03 for Phoenix, AZ, stratified by season
                 (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-255
    

    -------
                             Winter
                                                                     Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o
    O O (SEC
    
    OGBOO O
    GED
    OO O
    
    Summer
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    o
    c
    
    O (SHB
    
    OdE>GD
    D (2BD
    OO
    
    -------
                               Winter
                                                                          Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    (
    
    
    OOOD
    OO 
    -------
                             Winter
                                                                    Spring
    PM10 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o
    02X30
    
    O O O
    O O
    O
    
    Summer
    PM10 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    o
    
    
    
    OGD
    
    O O
    O O
    O O
    (GSQSD
    
    
    O(
    
    
    (
    Fall
    
    
    
    
    
    
    OOGD
    
    ) O
    GO
    OO
    )QO)O
    
    OOO
    
    OO
    (D)
    O O
    O OOGD
    Figure A-188. Correlations between 24-h PM2.s and co-located 24-h avg PMio, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg 03 for St. Louis, MO, stratified by season
                 (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-258
    

    -------
                             Winter
                                                                    Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    oo
    o
    o
    o
    
    
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    o o
    o
    o
    o
    
    
    
    
    
    
    
    
    Fall
    
    
    
    
    
    
    o o
    o
    o
    o
    
    
    
    
    o
    o
    o
    
    
    Figure A-189.  Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                  and CO and daily maximum 8-h avg 03 for Atlanta, GA, stratified by season (2005-
                  2007). One point is included for each available monitor pair.
    December 2009
    A-259
    

    -------
                             Winter
                                                                    Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    ©
    
    o
    
    o o
    o
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    GD
    
    O
    
    oo
    CD)
    
    
    
    
    
    
    Fall
    
    
    
    
    
    
    <32>
    
    O
    
    O O
    OO O
    
    (22)
    
    O
    
    OO
    O (SO
    Figure A-190. Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg 03 for Birmingham, AL, stratified by season
                 (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-260
    

    -------
                             Winter
                                                                    Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    OOODO
    OO
    O ODO
    O OD
    O O O
    O
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    (
    
    am
    o o
    ©o o
    oooo
    ) OO
    GD
    
    
    
    
    
    
    Fall
    
    
    (
    
    
    
    OCE)
    OO
    OOO O
    OS)
    OS)
    o© o
    
    (330
    O
    D (30
    
    -------
                             Winter
                                                                    Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o
    O Q88HD
    O
    O
    O
    
    
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    OTE
    O
    O
    O
    
    O OO
    
    
    
    
    
    
    Fall
    
    
    
    
    
    
    O (2XSE)
    O
    O
    O
    
    o e
    
    OOODO
    o
    o
    o
    
    o o o
    Figure A-192. Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg 03 for Chicago, IL, stratified by season (2005-
                 2007). One point is included for each available monitor pair.
    December 2009
    A-262
    

    -------
                             Winter
                                                                    Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o
    am)
    o
    o o
    oo
    oo
    
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    c
    (SD>
    c
    o o
    oo
    o
    ) O
    
    
    
    
    
    o
    Fall
    
    
    
    
    
    o o
    ©GD
    C
    OD
    O O
    ©
    O
    
    
    -------
                             Winter
                                                                     Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o
    oo
    
    o
    
    o
    
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    oo
    
    o
    
    o
    o o
    
    
    
    
    
    
    Fall
    
    
    
    
    
    
    o oo
    
    o
    
    o
    o o
    
    oo
    
    o
    
    o
    o o
    Figure A-194.  Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                  and CO and daily maximum 8-h avg 03 for Detroit, Ml, stratified by season (2005-
                  2007). One point is included for each available monitor pair.
    December 2009
    A-264
    

    -------
                             Winter
                                                                    Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    o<
    o
    
    o o
    O 
    Figure A-195. Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg 03 for Houston, TX, stratified by season
                 (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-265
    

    -------
                               Winter
                                                                         Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    CD(DK2)
    o am
    
    GD
    OGDO
    
    -------
                             Winter
                                                                    Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    ooo
    ©
    o
    o
    
    
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    GOO
    OO
    O O
    o
    OO
    o
    
    
    
    
    
    
    Fall
    
    
    
    
    
    
    000
    OO
    o o
    o
    o
    o
    
    OO
    00
    o o
    o
    GO
    o
    Figure A-197. Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg Os for New York, NY, stratified by season
                 (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-267
    

    -------
                             Winter
                                                                     Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    OB2)
    
    O OS)
    O02D
    O O
    
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    
    (
    
    (SOO
    
    O OOO
    O O
    3DO
    O 00
    
    
    
    
    C
    
    Fall
    
    
    
    
    
    
    GO
    
    OD OD
    OOO
    ) OO
    O O
    
    00)
    
    oooo
    O 
    -------
                               Winter
                                                                          Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    G3DO
    <3»0>
    O
    OO O
    O (3SSS)
    O 
    
    
    
    
    (
    
    (
    O OO
    C
    O
    ms)
    008D O GOO
    3SHED
      P M2.5 (daily avg)'
    
    
     PM10-2.5 (daily avg)-
    
    
       SO2 (daily avg)'
    
    
       NO2 (daily avg)<
    
    
        CO (daily avg)<
    
    
     O3 (daily max 8-hr)'
                               Summer
                                                                          Fall
    
    
    O
    C
    C
    I
    O GBOO
    C
    D
    )
    -------
                             Winter
                                                                     Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    
    O O (SEC
    
    GHOO O
    O CD
    OO OO
    
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    
    c
    o
    
    O (&8D
    
    oss>o
    • OOD O
    ooo o
    <3XS)
    
    
    
    
    (
    
    Fall
    
    
    
    o
    
    
    ozm
    
    OO3DO O
    O (JD O
    O OO
    GOOO O
    oooo
    Figure A-200.  Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                  and CO and daily maximum 8-h avg 03 for Pittsburgh, PA, stratified by season
                  (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-270
    

    -------
                               Winter
                                                                          Spring
    PM2.5 (daiV avg)-
    PM10-2.5 (daiV avg)-
    SO2 (daity avg)-
    NO2 (daity avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    I
    
    
    (OEDCSI
    OO <00
    
    D (D)
    CE) O
    O OO
    
    
    
    i
    C
    c
    I
    OD OSD
    
    DOO
    > O ODO
    O O
    DODO)
      P M2.5 (daily avg)'
    
    
     PM10-2.5 (daily avg)-
    
    
       SO2 (daily avg)'
    
    
       NO2 (daily avg)<
    
    
        CO (daily avg)<
    
    
     O3 (daily max 8-hr)'
                               Summer
                                                                           Fall
    
    (
    O
    
    I
    OGDO (D)
    )© O
    O O OO
    OD O
    OXODQD O
    
    C
    O
    
    GDO
    Figure A-201.  Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                   and CO and daily maximum 8-h avg 03 for Riverside, CA, stratified by season
                   (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-271
    

    -------
                             Winter
                                                                    Spring
    P M2. 5 (daily avg)-
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)'
    O3 (daily max 8-hr)-
    
    
    
    
    
    (
    02X30
    
    OO O
    o
    OGD
    DOO
    Summer
    P M2. 5 (daily avg)'
    PM10-2.5 (daily avg)-
    SO2 (daily avg)-
    NO2 (daily avg)-
    CO (daily avg)-
    O3 (daily max 8-hr)-
    
    
    c
    
    
    
    OGD
    
    O O O
    O O
    OOO
    OOD
    
    
    
    
    
    
    Fall
    
    
    
    
    
    
    OOGD
    
    OO O
    OO
    O OO
    00 OOO
    
    OOO
    
    GOD
    OO
    GDO
    (BDO
    Figure A-202. Correlations between 24-h PMi0 and co-located 24-h avg PM2.6, PMi0-2.5, S02, N02
                 and CO and daily maximum 8-h avg 03 for St. Louis, MO, stratified by season
                 (2005-2007). One point is included for each available monitor pair.
    December 2009
    A-272
    

    -------
    A.3.   Source Apportionment
    
    A.3.1.  Type of Receptor  Models
    Table A-51.    Different receptor models used in the Supersite source apportionment studies: chemical
                     mass  balance.
          Receptor Model
                                   Description
         Strengths and
          Weaknesses
    Effective Variance CMB42'1'1
    
    (Note that all models based on
    eq 1 or 2 are CMB equations.
    The term CMB used here
    reflects the historical solution in
    which source profiles are
    explicitly used as model input
    and a single sample effective
    variance solution is reported.)
    
    CMB software is currently
    distributed by EPA. The most
    recent version is the CMB 8.2,
    which is run in the Microsoft
    Windows system.
    Principle
    
    Ambient chemical concentrations are expressed as the sum of products of species
    abundances in source emissions and source contributions (Equations A-1 or A-2). These
    equations are solved for the source contribution estimates when ambient concentrations
    and source profiles are input. The single-sample effective variance least squares is the
    most commonly used solution method because it incorporates uncertainties of ambient
    concentrations and source profiles in the estimate of source contributions and their
    uncertainties. This reduced to the tracer solution when it is assumed that there is one
    unique species for each source. Choices of source profiles should avoid collinearity, which
    occurs when chemical compositions of various source emissions are not sufficiently
    different.121
                          r
                             iklmn
    ^
    ~>  rj-\     C1
    
     ijm  ijklmn  iklmn
                                                                                      for i = 1 to I
    Strengths
    
    Software available providing
    a good user interface.
    
    Provides quantitative
    uncertainties on source
    contribution estimates based
    on input concentrations,
    measurement uncertainties,
    and collinearity of source
    profiles.
    
    Quantifies contributions from
    source types with single
    particle and organic
    compound measurements.
    
    Weaknesses
                                Data Needs
                                CMB requires source profiles, which are the mass fractions of particulate or gas species in
                                source emissions. The species and particle size fraction measured in source emissions
                                should match those in ambient samples to be apportioned. Several sampling and analysis
                                methods provide time-integrated speciation of PM2 5 and volatile organic compounds
                                (VOCs) for CMB. Source profiles are preferably obtained in the same geographical region
                                as the ambient samples, although using source profiles from different regions is commonly
                                practiced in the literature. The practitioner needs to decide the source profiles and species
                                being included in the model, on the basis of the conceptual model and model performance
                                measures.
    
                                Output
    
                                Effective variance CMB determines, if converged,  source contributions to each sample in
                                terms of PM or VOC mass. CMB also generates various model performance measures,
                                including correlation R2, deviation X2, residue/ uncertainty ratio, and MPIN matrix that are
                                useful for refining the model inputs to obtain the best and most meaningful source
                                apportionment resolution.
                                                                 Equation A-1  Completely compatible
                                                                               source and receptor
                                                                               measurements are not
                                                                               commonly available.
    
                                                                               Assumes all observed mass
                                                                               is due to the sources
                                                                               selected in advance, which
                                                                               involves some subjectivity.
    
                                                                               Chemically similar sources
                                                                               may result in collinearity
                                                                               without more specific
                                                                               chemical markers.
                                                                                             Equation A-2
                                                                               Typically does not apportion
                                                                               secondary particle
                                                                               constituents to sources. Must
                                                                               be combined with profile
                                                                               aging model to estimate
                                                                               secondary PM.
    12 Hidy and Friedlander (1972,156546)
    121 Vtetson et al. (1997,1571211122(1984, 045693)
                                                                                                        Source: Watson et al. (2008,1571281
    December 2009
                                     A-273
    

    -------
    Table A-52.    Different receptor models used in the Supersites source apportionment studies: factor
                      analysis.
        Receptor Model
                                      Description
          Strengths and
           Weaknesses
    PMF
    
    PMFx(PMF2andPMF3)
    software is available from
    Dr. Pentti Paatero at the
    University of Helsinki,
    Finland. This software is a
    Microsoft DOS application.
    EPA distributes EPA PMF76
    version 1.1 as a Microsoft
    Windows application  with
    better user interface.
    Principle
    
    PMFx contains PMF2 and PMF3. PMF2 solves the CMB equations (i.e., Equations A-2 and A-
    3) using an iterative minimization algorithm. Source profiles Fj and contribution Sjt are solved
    simultaneously. The non-negativity constraint is implemented in the algorithm to decrease
    the number of possible solutions (local minimums) in the PMF analyses, because both
    source profile and contribution should not contain negative values. There is rotational
    ambiguity in all two-way factor analyses (i.e.,Fjtand Sjt matrices may be rotated and still fit
    the data). PMF2 allows using the FPEAK parameter to control the rotation. A positive FPEAK
    value forces the program to search such solutions where there are many zeros and large
    values but few  intermediate values in the source matrix Fjt.Fkey can further bind individual
    elements in FjiO zero  On the basis of a similar algorithm, PMF3 solves a three-way problem.
    Strengths
    
    Software available.
    
    Can handle missing or below-
    detection-limit data.
    
    Weights species
    concentrations by their
    analytical precisions.
    
    Downweight outliers in the
    robust mode.
    PMFx and UNMIX estimate Fj and Sjt by minimizing:
    
    
                           0 or x2= 22 f»vf= 22 [(
                                                                                                                Derives source profiles from
                                                                                                                ambient measurements as
                                                                                                                they would appear at the
                                                                                                                receptor (does not require
                                                                                                  Equation A-3 source measurements).
                              Where the weighing factor, oil, represents the magnitude of Eit, PMFx limits solutions of
                              Equation A-2 to non-negative  Fj and Sjt.
    
                              Data Needs
    
                              A large number of ambient samples (usually much more than the number of factors in the
                              model) are required to produce a meaningful solution. Species commonly used in PMF are
                              also those in CMB. Weighting factors associated with each measurement need to be
                              assigned before analysis. The practitioner also needs to decide the number of factors,
                              FPEAK, and Fkey in the model.
    
                              Output
    
                              PMFx reports all the elements in Fs and Sj matrices (PMF2).  It also calculates model
                              performance measures such as deviation X2 and standard deviation of each matrix element.
                              The practitioner needs to interpret the results linking them to source profiles and source
                              contributions.
                                                                                      Weaknesses
    
                                                                                      Requires large (>100) ambient
                                                                                      datasets.
    
                                                                                      Need to determine the number
                                                                                      of retaining factors.
    
                                                                                      Requires knowledge of source
                                                                                      profiles or existing profiles to
                                                                                      verify the representativeness
                                                                                      of calculated factor profiles
                                                                                      and uncertainties of factor
                                                                                      contributions.
    
                                                                                      Relies on many
                                                                                      parameters/initial conditions
                                                                                      adjustable to model input;
                                                                                      sensitive to the preset
                                                                                      parameters.
    ME2125
    
    ME2 code is available from
    Dr. Pentti Paatero at the
    University of Helsinki,
    Finland as a Microsoft DOS
    application.
    Principle
    
    The PMFx algorithm is derived from ME2. Unlike PMFx that is limited to questions in the
    form of Equation A-1 or A-2, ME2 solves all models in which the data values are fitted  by
    sums of products of unknown (and known) factor elements. The first part of the algorithm
    interprets instructions from the user and generates a table that specifies the model. The
    second part solves the model using an iterative minimization approach. Additional constraints
    could be programmed into the model to reduce the ambiguity in  source apportionment.
    These constraints may include known source profiles and/or contributions (e.g., contributions
    are known to be zero in some cases).
    
    Data Needs
    
    Data needs are similar to those of PMFx but are more flexible. In theory, any measured or
    unknown variables may be included in the model as long as they satisfy linear relationships.
    The users  need to specify the model structure, the input, and the output.
    
    Output
    
    ME2 calculates and reports all unknown variables in the model.
    Strengths
    
    Software available.
    
    Can handle user-specified
    models.
    
    Possibility to include all
    measured variables into the
    model, such as speciated
    concentration over different
    time scales, size distributions,
    meteorological variables, and
    noise parameters.
    
    Weaknesses
    
    Require substantial training to
    access the full feature of the
    software and develop a model.
    
    Generally requires large
    ambient datasets.
    
    Need to assume linear
    relationships between all
    variables.
    
    Relies on many
    parameters/initial conditions
    adjustable to model input;
    sensitive to  the preset
    parameters.
    December 2009
                                          A-274
    

    -------
        Receptor Model
                                       Description
          Strengths and
           Weaknesses
    UNMIX ^<12b
    
    UNMIX code is available
    from Dr. Ron Henry at the
    University of Southern
    California as an MatLab
    application. A stand-alone
    version (UNMIX version 6) is
    also available from EPA.
    Principle
    
    UNMIX views each sample as a data point in a multidimensional space with each dimension
    representing a measured species. UNMIX solves Equations A-2 and A-3 by using a principle
    component analysis (PCA) approach to reduce the number of dimensions in the space to the
    number of factors that produce the data, followed by an unique  "edge detection" technique to
    identify "edges" defined by the data points in the space of reduced dimension (e.g  Figures 1
    and 3). The number of factors is estimated by the NUMFACT algorithm in advance   , which
    reports the R and signal-to-noise (S/N) ratio associated with the first N principle components
    (PCs) in the data matrix. The number of factors should coincide with the number of PCs with
    S/N ratio >2. Once the data are plotted on the reduced space, an edge is actually a
    hyperplan  that signifies missing or small contribution from one or more factors. Therefore,
    UNMIX searches all the edges  and uses them to calculate the vertices of the simplex, which
    are then converted back to source composition and contributions. Geometrical concepts  of
    self-modeling curve resolution are used to ensure that the results obey (to within error) non-
    negativity constraints on source compositions and contributions.
    
    Data Needs
    
    A large number of ambient samples (usually much more than the number of factors in the
    model) are required to achieve a meaningful solution. Species commonly used in UNMIX are
    also those in CMB. The measurement precision is not required. The practitioner needs to
    specify the number of factors on the basis of the NUMFACT results.
    
    Output
    
    UNMIX determines all the elements in the factor (Fs) and contribution (Sj)  matrices. It also
    calculates  the uncertainty associated with the factor elements and model performance
    measures  including: (1) R2, (2)  S/N ratio, and (3) strength.
    Strengths
    
    Software available with
    graphical user interface.
    
    Does not require source
    measurements.
    
    Provide graphical problem
    diagnostic tools (e.g., species
    scatter plot).
    
    Provide evaluation tools (e.g.,
    R2, S/N ratio).
    
    Weaknesses
    
    Requires large (>100) ambient
    datasets.
    
    Need to assume or
    predetermine number of
    retained factors.
    
    Does not make explicit use of
    errors or uncertainties in
    ambient measurements.
    
    Cannot use samples
    containing missing data in any
    species.
    
    Limited to a maximum of 7 or
    14 (UNMIXversion 6) factors.
    
    Can report multiple or no
    solutions.
    
    Requires knowledge of
    existing source profiles to
    evaluate the solutions.
    December  2009
                                           A-275
    

    -------
        Receptor Model                                        Description                                          Strengths and
                                                                                                                       Weaknesses
    
    PDRM97                   Principle                                                                          Strengths
    
    PDRM was developed under PDRM estimates contributions from selected stationary sources for a receptor site using high  Explicitly include
    the Supersites Program and  time-resolution measurements and meteorological data. In PDRM, Equation A-2 is modified   meteorological information and
    requires MatLab or          to:                                                                                stack configuration of
    equivalent software to                                                                                         stationary sources into the
    perform the calculation.                                     ,,   ,v,                                           model.
                                                         4=^0^1  +Ł>
                                                              j       J1                           Equation A-4  Do not require source
                                                                                                                measurements.
                              where ŁRU is interpreted as the emission rate of species i from stationary source j and (X/Q,t               .
                              is the meteorological dispersion factor averaged over the time interval t. Equation A-4 is      Uo n.  n™   lnte/Pl'et tne
                              solved for  ERij and (X/Q,t simultaneously by a nonlinear fit minimizing the objective function,  relatlons between factors and
    
    
                                                                                                                Commercial software (e.g.,
                                                                       .••v'.™"    f                               MatLab) available for
                                                                       (oJ   -c,                                 performing nonlinear fit.
                                                                                                 Equation A-5 Suitab|e for hjgh time-
    
                              Because the number of solutions for a product of unknowns is infinite, additional constraints   resolutlon measurement.
                              are set up for (X/Q,t on the basis of the Gaussian plume model, thus:                      Weaknesses
    
                                                                               »,                               Can only handle stationary
                                                                           IB\Q)                                 sources but not area or mobile
                                                                               11                                sources.
    
                                                             1    —l   1Al—I  1iz~Tl                        Need to assume that only
                                                           2»vve»l-2,If/|""|   2'  ,r,  /j                        stationary sources are
                                                            - exp
                                                                  1  ./+)l,!,,                                     considered in the model
                                                                  2\
                                                                                                                contribute significantly for a
                                                                                          Equations A-6 & A-7 mteeasurement at the receP"»
    
                              Equations A-6 and A-7 limit the solution of Equation A-5 within the lower (LB) and upper (UB)  Do not account for uncertainty
                              bound of those predicted by the Gaussian plume model using different parameterizations.     jn (ne measurement
    
                              Data Needs                                                                       Meteorological data may not
    
                              PDRM requires speciated measurements at a higher time-resolution than typical CMB or      be alwaVs avallable or
                              PMF applications because of the fast-changing meteorological parameters. PDRM also      accurate.
                              requires data for Equation A-7: transport speed (u), lateral and vertical dispersion parameters Gaussian plume model may
                              (oy and oz), and stack height (h).                                                     not be representative of the
                              0UtpUt                                                                            actual atmospheric dispersion.
    
                              PDRM determines emission rates and contributions from each point source considered in     Sensitive to the imposed
                              the model at the same time resolution as the measurement.                              constraints (UB and LB).
    December 2009                                                A-276
    

    -------
        Receptor Model
    Description
    Strengths and
     Weaknesses
    PLSL
                               Principle
    
                               PLS examines the relationships between a set of predictor (independent) and response
                               (dependent) variables. It assumes that the predictor and response variables are controlled
                               by independent "latent variables" less in number than either the predictor or the response
                               variables. In recent applications,96 PM chemical composition and size distribution are used
                               as predictor (X) and response (Y) variables, respectively. Equation A- 2 is modified to:
                                                                                                    Equation A-8
                                                                                                    Equation A-9
                               where T and U are matrices of so-called "latent variables," and P and C are loading matrices.
                               If X and Y are correlated to some degree, T and U would show some similarity. Equations
                               A-8 and A-9 are solved by an iterative algorithm "NIPALS," which attempts to minimize E,D,
                               and the difference between T and U simultaneously. If T and U end up being close enough,
                               the X and Y variables can be  explained by the same latent variables. These latent variables
                               may then be interpreted as source or source categories.
    
                               Data Needs
    
                               Typical applications of PLS require both chemical speciated and size-segregated
                               measurements. The practitioner needs to decide the number of latent variables on the basis
                               of the correlation of resulting T and U matrices.
    
                               Output
    
                               PLS calculates latent variables, which are common factors best explaining the predictor and
                               response variables, and the residues from fitting. Rx and Ry,
                                                     Strengths
    
                                                     Fit two types of measurements
                                                     (e.g., chemistry and size) with
                                                     common factors. Provide more
                                                     information to identify sources.
    
                                                     Analyze strongly collinear and
                                                     noisy dataset.
    
                                                     Do not require source
                                                     measurements.
    
                                                     Weaknesses
    
                                                     Requires large (>100) ambient
                                                     datasets.
    
                                                     Difficult to relate latent
                                                     variables to any physical
                                                     quantities.
    
                                                     Do not provide quantitative
                                                     source contribution estimates.
    
                                                     Need to decide the number of
                                                     latent variables.
    
                                                     Do not explicitly make use of
                                                     measurement uncertainties.
    
                                                     Can result in no solution.
                                                            R, = 1 - var(ŁVvar(Jf)
                                                                                                   Equation A-10
                                                                                                   Equation A-11
    
    
                               indicate the degree to which variables X and Y are explained by the latent variables.
    Henry (1997. 0209411
    Lewis etal. (2003, 088413)
    Ogulei et al. (2006,1199751
    Park etal. (2005,156844)
    Paatero (1997. 087001)
    Paatero et al. (2002,1568361
    Paatero (1999.1568351
    Henry (2003,1565401
                                                                                                                  Source: Watson et al. (2008,1571281
    December  2009
        A-277
    

    -------
    Table A-53.    Different receptor models used  in the Supersites source apportionment studies: tracer-
                      based methods.
           Receptor Model
                                  Description
                      Strengths and Weaknesses
    The EF method may use a MLR
    algorithm, which is available in
    most statistical and spreadsheet
    software
    Principle
    
    A tracer (or marker) for a particular source or source category is a species
    enriched heavily in the source emission against other species and other sources.
    Using EFs-, concentration of the ith pollutant at a receptor site at time t (i.e., Ci,t)
    can be expressed as:
                    Strengths
    
                    No special software needed.
    
                    Indicate presence or absence of
                    particular emitters.
    
                    Provides evidence of secondary PM
                    formation and changes in source
                    impacts by changes in ambient
                    composition.
    
    Equation A-12  Could use a large (>100) dataset or a
                    small (e.g., < 10) dataset.
                                  where the enrichment factor EFi,pj is the ratio of emission rate of the pollutant of
                                  interest (Fj) and tracer species (Fpj) from source j. Cpjil is the concentration of
                                  tracer species for source j at time t, and Zi,t represents contributions from all other
                                  sources (including the background level). The solution for eq 12 is situation-
                                  dependent. EFjipj is usually unknown but may be estimated from source profiles,
                                  edges of a two-way scatter plot or the ratio of Cit to Cpjl for a particular period
                                  when it is believed that a single source is dominant. In cases where ZM is a
                                  constant, EFiipj may be derived from MLR.
    
                                  Data Needs
    
                                  The minimum data needs include concentrations of all primary tracers at the
                                  receptor site. Known EFs or background levels are helpful.
    
                                  Output
    
                                  The EF method determines contributions to species i from each source
                                  considered in the model.
                                                                            Weaknesses
    
                                                                            Semiquantitative method, not specific
                                                                            especially when the EFs are
                                                                            unknown in advance.
    
                                                                            Limited to sources with unique
                                                                            markers.
    
                                                                            Tracer species must be exclusively
                                                                            from the sources or source
                                                                            categories examined.
    
                                                                            Provide very limited error estimates.
    
                                                                            More useful for source/process
                                                                            identification than for quantification.
    NNLS
    
    The MatLab Optimization Toolbox
    provides a function "Isqnonneg"
    for performing the NNLS
    calculation.
    Principle
    
    NNLS also solves the EF equation (Equation A-12 or equivalent) with known
    target species and tracer concentrations. Conventional MLR solutions to eq 12
    may lead to negative EFs due to the uncertainty in measurements or colinearity in
    source contributions. This is avoided in the NNLS approach since additional non-
    negative constraints are built into the algorithm, i.e.:
                    Strengths
    
                    Implemented by many statistical
                    software packages.
    
                    Generate only non-negative EFs or
                    regression coefficients.
    
                    Do not require source
                    measurements.
                                                                                                           Possible to include meteorological or
                                                                                           Equation A-13  °'ner (besides chemistry) data into
                                                                                                           the model.
                                  Utilizing orthogonal decomposition, a NNLS problem can be reduced to the more
                                  familiar least-distance programming and solved by a set of iterative subroutines
                                  developed and tested by Lawson and Hanson.131 In a more general sense,
                                  NNLS linearly relates a response variable to a set of independent variables with
                                  only non-negative coefficients.
    
                                  Data Needs
    
                                  When applied to EF or MLR problems, NNLS requires the concentration of target
                                  (response) and tracer (independent) species.
    
                                  Output
    
                                  NNLS generates  non-negative regression coefficients for an EF/MLR problem and
                                  these coefficients can be related to the source contributions.
                                                                            Weaknesses
    
                                                                            Require a large (>100) set of ambient
                                                                            measurements.
    
                                                                            Semiquantitative method, not
                                                                            specific.
    
                                                                            Do not explicitly consider
                                                                            measurement uncertainties.
    
                                                                            Tracer species must be exclusively
                                                                            from the sources or source
                                                                            categories examined.
    
                                                                            Non-negative constraints may not be
                                                                            appropriate in some cases.
    December 2009
                                      A-278
    

    -------
           Receptor Model
    Description
    Strengths and Weaknesses
    FAC
                                   Principle
    
                                   FAC provides a simple mean of estimating the SOA production rate using the
                                   emission inventories of primary precursor VOCs. FAC is actually a source-
                                   oriented modeling technique but it does not take into account all the atmospheric
                                   processes. FAC is defined as the fraction of SOA that would result from the
                                   reactions of a particular VOC:
                                                  [SQA] = ^ FACi x ip/OGi], x Fraction of VOC /reacted!
                                                                                            Equation A-14
                                   where [VOCjo is the emission rate of VOC: and [SOA] is the formation rate of
                                   SOA. Equation A-14 can be viewed as an extension of Equation -12 but
                                   concentrations are replaced with emission rates and EFs are replaced with FACs.
                                   FAC and the fraction of VOC reacted under typical ambient conditions have been
                                   developed for a large number of hydrocarbons >C6 11. The most significant SOA
                                   precursors are aromatic compounds (especially toluene, xylene, and
                                   trimethylbenzenes) and terpenes. In most applications, these FACs are used
                                   directly to estimate SOA.
    
                                   Data Needs
    
                                   FAC requires the VOC emission inventory in the region of interest. The knowledge
                                   of 03 and radiation intensity is also helpful for slight modifications of the FACs.
    
                                   Output
    
                                   FAC method estimates the total production rate of SOA.
                                               Strengths
    
                                               Link SOA to primary VOC emissions
                                               so that SOA can also  be treated as
                                               primary particles in the PM modeling.
    
                                               Simple and inexpensive.
    
                                               Weaknesses
    
                                               Ignore the influence of aerosol
                                               concentration and temperature-
                                               dependent gas-particle partitioning on
                                               SOA yield.
    
                                               Limited  by the accuracy of VOC
                                               emission inventory.
    
                                               Do not directly infer the contribution
                                               of each  source to ambient SOA
                                               concentration.
    
                                               Difficult  to verify.
    Grosjean and Seinfeld (1989, 0456431
    Darns etal. (1970,156379)
    Reimann and De Capital (2000, 0132691
    Lawson and Hanson (1974,1566731
    Wang and Hopke (1989,1571051
                                                                                                                 Source: Watson et al. (2008, 157128)
    December  2009
        A-279
    

    -------
    Table A-54.    Different receptor models used  in the Supersites source apportionment studies:
                      meteorology-based methods.
          Receptor Model
     Description
    Strengths and
     Weaknesses
    CPF1
                                 Principle
    
                                 CPF estimates the probability that a given source contribution from a given wind direction will
                                 exceed a predetermined threshold criterion (e.g., upper 25th percentile of the fractional contribution
                                 from the source of interest). The calculation of CPF uses source contributions (i.e., 03 in Equation
                                 A-2) determined for the  receptor site and local wind direction data matching each of the source
                                 contributions in time. These data are then segregated to several sectors according to wind direction
                                 and the desired resolution (usually 36 sectors at a  10° resolution). Data with very low wind speed
                                 (e.g., < 0.1 m/sec) are usually excluded from analysis because of the uncertain wind direction. CPF
                                 is then determined by:
                                                                              .,
                                                                  CPRH) = -
                                                                            "is
                                                                                                        Equation A-15
                                 where mA6 is the number of occurrences in the direction sector 9 -> 9 + A6 that exceeds the
                                 specified threshold, and nA6 is the total number of wind occurrences in that sector. Because wind
                                 direction is changing rapidly, high-time resolution measurements (e.g., minutes to hours) are
                                 preferred for a CPF analysis. If the calculated source contributions represent long-term averages,
                                 wind direction needs to be averaged over the same duration. In addition to source contribution,
                                 CPF can be applied directly to pollutant concentration measurements at a receptor site.
    
                                 Data Needs
    
                                 CPF requires the time series of source contributions at a receptor site, which is usually determined
                                 by CMB or factor analysis methods using speciated measurements at the site. CPF also requires
                                 wind direction and wind speed data averaged over the same time resolution as the sampling
                                 duration.
    
                                 Output
    
                                 CPF reports the probability of "high" contribution from a particular source or factor occurring within
                                 each wind direction sector. The results are often presented in a wind rose plot.
                                                        Strengths
    
                                                        Infer the direction of
                                                        sources or factors
                                                        relative to the
                                                        receptor site.
    
                                                        Provide verification
                                                        for the source
                                                        identification made
                                                        by factor analysis
                                                        method.
    
                                                        Easy to implement.
    
                                                        Weaknesses
    
                                                        Criterion for the
                                                        threshold is
                                                        subjective.
    
                                                        Absolute source
                                                        contribution (or
                                                        fractional
                                                        contribution) may be
                                                        influenced by other
                                                        factors besides wind
                                                        direction (e.g.,  wind
                                                        speed, mixing
                                                        height).
    
                                                        Local and near-
                                                        surface wind
                                                        direction only has a
                                                        limited implication for
                                                        long-range transport.
    
                                                        Easy to be biased by
                                                        a small number of
                                                        wind occurrences in
                                                        a particular sector.
    
                                                        Work better for
                                                        stationary sources
                                                        than area or mobile
                                                        sources.
    December 2009
    A-280
    

    -------
          Receptor Model
      Description
    Strengths and
     Weaknesses
    NPR1
                                 Principle
    
                                 NPR calculates the expected (averaged) source contribution as a function of wind direction
                                 following:
                                 where Wi is the wind direction for the ith sample and Si is the contribution from a specific source to
                                 that sample, determined from measurements at the receptor site. K is a weighting function called
                                 the kernel estimator. There are many possible choices for K. Henry et al.136 recommend either
                                 Gaussian or Epanechnikov functions. The most important decision in NPR is the choice of the
                                 smoothing  parameter A6.  If A6 is too large, S(6) will be too smooth and meaningful peaks could be
                                 lost. If it is too small, S(6)  will have too many small, meaningless peaks. A6 needs to be chosen
                                 according to the project-specific spatial distribution of sources. NPR also estimates the confidence
                                 intervals of S(6) based on the asymptotic normal distribution of the kernel estimates, thus:
                                                         Strengths
    
                                                         Infer the direction of
                                                         sources or factors
                                                         relative to the
                                                         receptor site.
    
                                                         Provide verification
                                                         for the source
                                                         identification made
                                                         by factor analysis
                                                         method.
                                                         Require no
                                         Equation A-16 assumption about
                                                         the function form of
                                                         the relationship
                                                         between wind
                                                         direction and source
                                                         contribution.
                                 Data Needs
                                 NPR requires the same data as the CPF method, including the time series of source/factor
                                 contributions (or fractional contributions) at the receptor site and local wind direction data matching
                                 the sampling duration in time.
    
                                 Output
    
                                 NPR reports the distribution of source contribution as a function of wind direction and the
                                 confidence level associated with it.
                                                         Provide uncertainty
                                                         estimates.
    
                                                         Easy to implement.
    
                                                         Weaknesses
    
                                                         Choices for the
                                                         kernel estimator and
                                                         smoothing factor are
                                                         subjective.
    
                                                         Absolute source
                                                         contribution (or
                                         Equation A-17 fractional
                                                         contribution) may be
                                                         influenced by other
                                                         factors besides wind
                                                         direction (e.g., wind
                                                         speed, mixing
                                                         height).
                                                         Local and near-
                                                         surface wind
                                                         direction only has a
                                                         limited implication for
                                                         long-range transport.
    
                                                         Easy to be biased by
                                                         a small number of
                                                         wind occurrences in
                                                         a particular sector.
    
                                                         Work better for
                                                         stationary sources
                                                         than area or mobile
                                                         sources.
    December  2009
    A-281
    

    -------
          Receptor Model
                                           Description
      Strengths and
       Weaknesses
    TSA1J"
    
    ISA requires the calculation of
    air parcel back trajectory, which
    is often accomplished using the
    HY-SPLIT model.115'139 HY-
    SPLIT version 4.5 is available
    at http://www.arl.noaa.gov/-
    ready/hysplit4.html.
    Principle
    
    Similar to CPF, ISA clusters the measured pollutant concentration or calculated source contribution
    according to the wind pattern. However, air parcel back trajectory, rather than local wind direction,
    is used. A back trajectory traces the air parcel backward in time from a receptor. The initial height is
    often between 200 and 1000 m above ground level where the wind direction could differ from the
    surface wind direction substantively. For each sample i, ISA obtains one or more trajectories and
    calculates their total residence time in the jth directional sector (Ty, i.e., the total number of 1-h
    trajectory end points that fall into the sector). The pollutant concentration or source contribution in
    the sample, Si, is then linearly apportioned into each directional sector according to T,J and
    averaged over all samples to produce the directional dependent pollutant concentration/source
    contribution for the period of interest:
    
                                                                                                             Equation A-18
                                  where N is the number of samples. Compared with CPF and NPR, ISA considers the entire air
                                  mass history rather than just the wind direction at the receptor.
    
                                  Data Needs
    
                                  ISA requires the time series of pollutant concentration or source contribution at the receptor site,
                                  and back trajectories initiated over the site during the sampling duration. Trajectory is usually
                                  calculated once every hour so ISA is more suitable for analyzing measurements of >1-h resolution.
    
                                  Output
    
                                  ISA reports the avg pollutant concentration or source contribution as a function of wind direction
                                  based on back trajectory calculations.
    Strengths
    
    Infer the direction of
    sources or factors
    relative to the
    sampling site.
    
    Provide verification
    for the source
    identification made
    by factor analysis
    method.
    
    Account for air mass
    transport over
    hundreds to
    thousands of
    kilometers and on
    the order of several
    days.
    
    Can  represent plume
    spread from vertical
    wind shear at
    different hours of day
    by adjusting the
    initial height of back
    trajectories.
    
    Weaknesses
    
    Need to generate
    and analyze the back
    trajectory data.
    
    Uncertainty in back
    trajectory calculation
    increases with its
    length in  time.
    
    Source contribution
    depends  on not only
    trajectory residence
    time  but also
    entrainment
    efficiency, dispersion,
    and deposition.
    
    Difficult to resolve
    the direction of more
    localized sources.
    December 2009
                                         A-282
    

    -------
          Receptor Model
                                           Description
      Strengths and
       Weaknesses
    PSCF ™
    
    PSCF requires the calculation
    of air parcel back trajectory,
    which is often accomplished
    using the HY-SPLIT
    model.115'139 HY-SPLIT version
    4.5 is available at
    http://www.arl.noaa.gov/-
    ready/hysplit4.html.
    Principle
    
    Ensemble air parcel trajectory analysis refers to the statistical analysis on a group of trajectories to
    retrieve useful patterns regarding the spatial distribution of sources. Uncertainties associated with
    individual trajectory calculations largely cancel out for a sufficient number of trajectories or
    trajectory segments. As a popular ensemble back trajectory analysis, PSCF estimates the
    probability that an upwind area contributes to high pollutant concentration or source contribution.
    Back trajectories are first calculated for each sample at the receptor site. To determine the PSCF, a
    study domain containing the receptor site is divided into an array of grid cells. Trajectory residence
    time (the time it spends) in each grid cell is calculated for all back trajectories and for a subset of
    trajectories corresponding to "high" pollutant concentration or source contribution at the site. PSCF
    in cell (i,j) is then defined as:
                                                           PSCF,, =
                                   Sum of "high" residence time in cell (/, ft
                                     Sum of all residence time in cell it/i
                                                                                                              Equation A-19
                                  The criterion for high pollutant concentration or source contribution is critical for the PSCF
                                  calculation. The 75th or 90th percentileofthe concentration or factor is often used.  '  '
                                  Residence time can be represented by the number of trajectory end points in a cell.
    
                                  Data Needs
    
                                  Similar to TSA, PSCF calculation requires the time series of pollutant concentration or source
                                  contribution at the receptor site, and back trajectories initiated over the site during the sampling
                                  period. Trajectories should be calculated with 1 -to 3-h segment to reduce the uncertainty from
                                  interpolation (if needed).
    
                                  Output
    
                                  PSCF reports the probability that an upwind area contributes  to high pollutant concentrations or
                                  source contribution at the downwind receptor site. The results are often presented as a contour plot
                                  on the map. A high probability usually suggests potential source region.
    Strengths
    
    Infer the location of
    sources or factors
    relative to the
    sampling site.
    
    Provide verification
    for the source
    identification made
    by factor analysis
    method
    
    Account for air mass
    transport over
    hundreds to
    thousands of
    kilometers and on
    the order of several
    days.
    
    Resolve the spatial
    distribution of source
    strength
    (qualitatively).
    
    Weaknesses
    
    Need to generate
    and analyze the back
    trajectory data.
    
    Need to correct for
    the central tendency
    (residence time
    always increases
    toward the receptor
    site regardless of
    source contribution).
    
    Uncertainty in back
    trajectory calculation
    increases with its
    length in  time.
    
    Source contribution
    depends  on not only
    trajectory residence
    time  but also
    entrainment
    efficiency, dispersion,
    and deposition.
    
    Difficult to resolve
    the location of more
    localized sources.
    December 2009
                                          A-283
    

    -------
          Receptor Model
                                                                        Description
                                                                                                 Strengths and
                                                                                                 Weaknesses
    SQTBA 117 143
    
    SQTBA requires the calculation
    of air parcel back trajectory,
    which is often accomplished
    using the HY-SPLIT
    model.115'139 HY-SPLIT version
    4.5 is available at
    http://www.arl.noaa.gov/-
    ready/hysplM.html.
                                  Principle
    
                                  SQTBA is another type of ensemble air parcel trajectory analysis. The concept of SQTBA is to
                                  estimate the "transport field" for each trajectory ignoring the effects of chemical reactions and
                                  deposition. Back trajectories are first calculated for each sample at the receptor site, and a study
                                  domain containing the receptor site is divided into an array of grid cells. SQTBA assumes that the
                                  transition probability that an air parcel at (x',y',f), where x' and y' are spatial coordinates and t'
                                  means time, will reach a receptor site at (x,y,t) is  approximately normally distributed along the
                                  trajectory with a standard deviation that increases linearly with time upwind  '  ,thus:
                                                                                               Strengths
    
                                                                                               Imply the location of
                                                                                               sources or factors
                                                                                               relative to the
                                                                                               sampling site.
    
                                                                                               Account for air mass
                                                                                               transport over
                                                                                               hundreds to
                                                                                               thousands of
                                                                                               kilometers and on
                                                                                                            Equation A-20
                                  where (X,Y) is the coordinate of the grid center, a is the dispersion speed, and x'(t') and x' (t')
                                  represent the trajectory. The probability field, Q, for a given trajectory is then integrated over the
                                  upwind period, T, to produce a two-dimensional "natural" (nonweighted) transport field:
                                                                ,,.._
                                                           4 (Jf. y \x ', y > =
                                                                          f°
                                                                             Qi.x, y, t\x', y', z'}
                                                                                                            Equation A-21
                                  After the transport field for each trajectory is established, they are weighted by the corresponding
                                  pollutant concentration or source contribution at the receptor site and summed to yield the overall
    
    
                                  ""Needs'
                                                                                               Resolve the spatial
                                                                                               distribution of source
                                                                                               strength
                                                                                               (qualitatively).
    
                                                                                               Weaknesses
    
    
                                                                                               and analyze the back
                                                                                               trajectory data.
    
                                                                                               Need to correct for
                                                                                               the central tendency
                                                                                               (res idence time
                                                                                               always increases
                                                                                               toward the receptor
                                                                                               site regardless of
                                                                                               source contribution).
    
                                                                                               Need to estimate
                                                                                               dispersion velocity.
    
                                                                                               inuoiue comnlicated
                                                                                               involve complicated
                                                                                               unclear.
    SQTBA requires the time series of pollutant concentration or source contribution at the receptor
    site, and back trajectories initiated over the site during the sampling period. Trajectories should be   n-ffi   ,, ,      ,
    calculated with 1to 3-h segment to reduce the uncertainty from interpolation (if needed).             the locationof rrore
    Output                                                                                    localized sources.
    
    SQTBA put more weight on trajectories associated higher pollutant concentration or source
    contribution and therefore the resulting field may imply the major transport path.
    December  2009
                                         A-284
    

    -------
          Receptor Model
      Description
                                                                                                                                  Strengths and
                                                                                                                                  Weaknesses
    RTWC 146
    
    RTWC requires the calculation
    of air parcel back trajectory,
    which is often accomplished
    using the HY-SPLIT
    model.115'139 HY-SPLIT version
    4.5 is available at
    http://www.arl.noaa.gov/
    ready/hys plit4.html
                                  Principle                                                                                    Strengths
    
                                  As an ensemble air parcel trajectory analysis, RTWC requires back trajectories calculated for each  Imply the location of
                                  sample at the receptor site, and a study domain containing the receptor site divided into an array of  sources or factors
                                  grid cells. RTWC assumes that no major pollutant sources are located along "clean" (associated     relative to the
                                  with low pollutant concentrations) trajectories and that "polluted" trajectories picked up emissions    sampling site.
                                  along their paths. In practice, RTWC distributes pollutant concentrations at the receptor to upwind
                                  grid cells along the back trajectories according to the trajectory residence times in those cells.117'14
                                                                          resident time In cell i
                                                                   '"'average residence time in each cell
                                  where Sk is the pollutant concentration or source contribution determined upon the arrival of
                                  trajectory k and Siik is the redistributed pollutant concentration or source contribution for cell i
                                  upwind.
                                  RTWC is known for the problem of "tailing effect," i.e., spurious source areas can be identified
                                  when cells are crossed by a very small number of trajectories. Although some corrections were
                                  proposed! 47 these approaches are purely empirical.
                                                           Account for air mass
                                                           transport over
                                                           hundreds to
                                                           thousands of
                                                           kilometers and on
                                                           the order of several
                                          Equation A-22  days.
    
                                                           Resolve the spatial
                                                           distribution of source
                                                           strength
                                                           (qualitatively).
                                                           Weaknesses
    
                                                           Need to generate
                                                           and analyze the back
                                                           trajectory data.
    
                                                           Need to correct for
                                                           the central tendency
                                                           and tailing effect.
    
                                                           The amount of
                                                           emission
                                                           entrainment should
                                                           not be proportional to
                                                           the residence time of
                                                           trajectories (so there
                                                           is no linear
                                                           relationship between
                                                           RTWC field and
                                                           source strength).
    
                                                           Physical meaning of
                                                           the RTWC field is
                                                           unclear.
    
                                                           Difficult to resolve
                                                           the location of more
                                                           localized sources.
      (Pekneyetal., 2006,086115)
     ' (Zhou etal., 2004,157190)
     '(Ashbaugh, 1983,156229)
    
     ' (Ashbaugh et al., 1984, 0451481
     '(Henry etal, 2002,136097)
     ' (Yu etal. ,2004, 101779)
    
     3(Parekh and Husain, 1981,156840)
     ](Hopke etal, 1995,156566)
     3(Keeler and Samson, 1989,156633)
    
     '(Sam son.1978.188974)
     5 (Samson. 1980. 0730101
     3 (Stohl, 1996,157014)
    
     '(Cheng etal, 1993,052294)
                                                                                                                    Source: (Watson et al., 2008,1571281
    December 2009
    A-285
    

    -------
    A.3.2. Source Profiles
    Table A-55. Source Profiles: Part 1
    Element
    Aluminum
    Antimony
    Arsenic
    Barium
    Cadmium
    Calcium
    Chloride ion
    Chromium
    Cobalt
    Copper
    Total carbon
    Gallium
    Gold
    Indium
    Iron
    Lanthanum
    Lead
    Magnesium
    Manganese
    Mercury
    Molybdenum
    Nickel
    Nitrate
    Organic
    carbon
    Palladium
    Phosphorus
    Potassium
    Rubidium
    Selenium
    Silicon
    Silver
    Sodium
    Strontium
    Sulfate
    Sulfur
    Motor Vehicle Exhaust -
    Symbol Gasoline
    
    Al
    Sb
    As
    Ba
    Cd
    Ca
    Cl-
    Cr
    Co
    Cu
    TC
    Ga
    Au
    In
    Fe
    La
    Pb
    Mg
    Mn
    Hg
    Mo
    Ni
    N03"
    OC
    Pd
    P
    K
    Rb
    Se
    Si
    Ag
    Na
    Sr
    S04"
    S
    Weight %
    0.1
    0.01
    
    0.01
    
    0.42
    0.39
    0.01
    
    0.02
    
    
    
    0
    1.27
    0
    0.08
    0.14
    0.01
    0
    
    0.01
    0.06
    59.37
    
    0.27
    0.01
    
    
    1.61
    
    0.01
    
    
    0.37
    Uncertainty
    N/A
    N/A
    
    N/A
    
    N/A
    N/A
    N/A
    
    N/A
    
    
    
    N/A
    N/A
    N/A
    N/A
    N/A
    N/A
    N/A
    
    N/A
    N/A
    N/A
    
    N/A
    N/A
    
    
    N/A
    
    N/A
    
    
    N/A
    Coal Combustion
    Weight %
    5.968
    0
    0
    1.3315
    0
    3.4536
    
    0.0176
    0
    0.0179
    4.2763
    0.014
    
    0
    2.916
    0
    0.068
    
    0.0284
    0
    0
    0.0072
    0
    0
    0
    0.9372
    0.4644
    0.0053
    0.0406
    9.0112
    0
    
    0.1964
    10.1716
    2.948
    Uncertainty
    0.5247
    0.0625
    0.0164
    1 .0801
    0.0341
    1.0411
    
    0.0041
    0.0432
    0.0112
    4.2579
    0.014
    
    0.0404
    0.3827
    0.2462
    0.0336
    
    0.0139
    0.0154
    0.0134
    0.0019
    0.2116
    2.9263
    0.0263
    0.6322
    0.0602
    0.0043
    0.0407
    0.5675
    0.0312
    
    0.0686
    8.9405
    2.729
    Highway
    Weight %
    5.729
    0
    0
    0.1377
    0
    2.5657
    
    0.0271
    0
    0.0219
    14.3927
    0
    
    0
    4.5713
    0
    0.067
    
    0.087
    0
    0
    0.0081
    0
    12.7127
    0
    0
    2.7161
    0.0184
    0
    17.596
    0
    
    0.0395
    1.1604
    0.598
    Road Dust
    Uncertainty
    0.4058
    0.0335
    0.0123
    0.1027
    0.019
    0.1388
    
    0.0023
    0.0668
    0.0101
    2.3449
    0.005
    
    0.022
    0.2661
    0.1341
    0.0074
    
    0.009
    0.0083
    0.0071
    0.0015
    0.094
    2.1296
    0.0151
    0.0324
    0.3069
    0.0023
    0.0024
    1.4183
    0.0175
    
    0.0078
    0.2003
    0.0509
    Unpaved Road Dust
    Weight %
    7.4822
    0
    0
    0
    0
    2.163
    
    0.0312
    0
    0.0474
    4.2671
    0
    
    0
    5.5128
    0
    0.0288
    
    0.1372
    0
    0
    0.0091
    0
    4.2671
    0
    0.1603
    2.8299
    0.0184
    0
    24.2969
    0
    
    0.0313
    0.8688
    0.2808
    Uncertainty
    0.9315
    0.1601
    0.0226
    0.5473
    0.0881
    1.0444
    
    0.0161
    0.0869
    0.0307
    3.7193
    0.0233
    
    0.1041
    2.1152
    0.6521
    0.0284
    
    0.0509
    0.0383
    0.0331
    0.0057
    0.6371
    2.2637
    0.0701
    0.044
    0.4949
    0.0093
    0.0108
    4.0089
    0.083
    
    0.0112
    1.3788
    0.3884
    Refinery
    Weight %
    8.4853
    0
    0
    0
    0
    0.1236
    
    0.0443
    0
    0.0299
    0
    0
    
    0
    1.4708
    0
    0.0097
    
    0.016
    0
    0.0079
    0.04
    0
    0
    0
    0.0689
    0.0825
    0
    0
    17.9733
    0
    
    0.0094
    2.3243
    0.6304
    Uncertainty
    2.3478
    0.0285
    0.0045
    0.0979
    0.0155
    0.056
    
    0.0127
    0.0218
    0.0082
    1.6175
    0.0059
    
    0.0183
    0.2216
    0.1146
    0.0063
    
    0.002
    0.0073
    0.0088
    0.0065
    0.0772
    1 .5288
    0.0127
    0.0144
    0.0234
    0.002
    0.0021
    5.1834
    0.0151
    
    0.0031
    3.4523
    0.9627
    December 2009
    A-286
    

    -------
    
    Thallium
    Tin
    Titanium
    Uranium
    Vanadium
    Yttrium
    Zinc
    Zirconium
    Ammonium
    Sodium ion
    Carbonate
    Organic
    carbon II
    Organic
    carbon III
    Organic
    carbon IV
    ECI
    Chlorine
    atom
    EC III
    EC
    Bromine
    Atom
    Organic
    carbon 1
    ECU
    Sulfur
    dioxide
    Potassium
    ion
    
    Tl
    Sn
    Ti
    U
    V
    Y
    Zn
    Zr
    NH4+
    Na+
    C03"
    OC2
    OC3
    OC4
    EC1
    Cl-
    EC3
    EC
    Br
    OC1
    EC2
    S02
    K+
    Motor Vehicle Exhaust- Coa| Combustion
    
    0 0.0527
    0.4315 0.0651
    
    0 0.0734
    0 0.006
    0.49 N/A 0.0797 0.0341
    0.0247 0.0043
    0.34 N/A 0.3476 0.1352
    
    
    
    
    
    
    0.0629 0.0221
    
    16.44 N/A 4.2763 3.0931
    0.0147 0.0154
    
    
    7262.6687 7677.5681
    0.1109 0.0571
    Highway Road Dust
    
    0 0.0298
    0.3612 0.0313
    
    0.0288 0.0074
    0.0046 0.0012
    0.0932 0.0256
    0.0128 0.0025
    0 0.025
    
    
    
    
    
    
    3.4403 0.5505
    
    1.68 0.9817
    0.0037 0.0011
    
    
    
    0.2295 0.1046
    Unpaved Road Dust Refinery
    
    0 0.1464 0 0.0254
    0.5258 0.1289 0.6178 0.0711
    
    0 0.0646 0.0432 0.0084
    0 0.0146 0 0.0029
    0.0502 0.021 0.0166 0.003
    0.0219 0.0168 0.0166 0.0022
    0 0.1317 0.3281 0.5565
    
    
    
    
    
    
    0.1519 0.0755 0.0186 0.0074
    
    0 2.9512 0 0.5283
    0 0.0078 0 0.0017
    
    
    
    0.1263 0.0744 0.0115 0.0059
                                                                                  Source: USA EPA Specials database http://www.epa.gov/ttnchie1/software/speciate/index.html
    December  2009
    A-287
    

    -------
    Part II
    Element
    Aluminum
    Antimony
    Arsenic
    Barium
    Cadmium
    Calcium
    Chloride ion
    Chromium
    Cobalt
    Copper
    Total carbon
    Gallium
    Gold
    Indium
    Iron
    Lanthanum
    Lead
    Magnesium
    Manganese
    Mercury
    Molybdenum
    Nickel
    Nitrate
    Organic carbon
    Palladium
    Phosphorus
    Potassium
    Rubidium
    Selenium
    Silicon
    Silver
    Sodium
    Strontium
    Sulfate
    Sulfur
    Thallium
    Tin
    Titanium
    Uranium
    Symbc
    Al
    Sb
    As
    Ba
    Cd
    Ca
    Cl-
    Cr
    Co
    Cu
    TC
    Ga
    Au
    In
    Fe
    La
    Pb
    Mg
    Mn
    Hg
    Mo
    Ni
    N03"
    OC
    Pd
    P
    K
    Rb
    Se
    Si
    Ag
    Na
    Sr
    S042"
    S
    Tl
    Sn
    Ti
    U
    Residential Wood
    Burning
    Weight %
    0.0034
    0.0002
    0.0003
    0.0093
    0.0013
    0.0664
    0.0028
    0.0003
    0.0005
    0.0002
    70.6416
    0
    
    0.0021
    0.0038
    0.0086
    0.0031
    
    0.003
    0.0004
    0
    0.0002
    0.2025
    49.4961
    0.0006
    0
    0.6346
    0.0007
    0.0001
    0.0443
    0.0023
    
    0.0006
    0.4553
    0.1533
    
    0.0006
    0.001
    
    Uncertainty
    0.0103
    0.0108
    0.0016
    0.0369
    0.0058
    0.0165
    0.0004
    0.0012
    0.0005
    0.0007
    7.1435
    0.0016
    
    0.0069
    0.0017
    0.0431
    0.0018
    
    0.0013
    0.0027
    0.0024
    0.0005
    0.0156
    5.481
    0.0047
    0.0051
    0.1008
    0.0007
    0.0008
    0.0167
    0.0054
    
    0.0009
    0.0359
    0.0173
    
    0.0092
    0.012
    
    Oil Combustion
    Weight
    %
    0
    0
    0.02
    0
    0
    0
    
    0.01
    0.05
    0.01
    3.55
    0.01
    
    0
    0.68
    0
    0
    
    0
    0
    0
    2.36
    0
    1.71
    0
    0
    0
    0
    0.03
    0
    0
    
    0
    25.29
    16.48
    
    0
    0.01
    
    Uncertainty
    0.05
    0.01
    0
    0.03
    0.01
    0.04
    
    0.01
    0.01
    0.01
    1 .0855
    0
    
    0.01
    0.1
    0.04
    0
    
    0
    0
    0
    0.23
    0
    0.56
    0
    0.65
    0
    0
    0
    0.09
    0
    
    0
    5.62
    1.62
    
    0.01
    0.01
    
    Weight
    %
    0
    0
    0
    0.01
    0
    0.01
    
    0
    0
    0
    98.94
    0
    
    0
    0
    0.02
    0
    
    0
    0
    0
    0
    0.06
    90.8
    0
    0.01
    0
    0
    0
    0.01
    0
    
    0
    0.53
    0.59
    
    0
    0
    
    DE
    Uncertainty
    0.01
    0.01
    0
    0.04
    0.01
    0.01
    
    0
    0
    0
    17.859
    0
    
    0.01
    0
    0.05
    0
    
    0
    0
    0
    0
    0.01
    14.79
    0
    0.02
    0
    0
    0
    0.01
    0.01
    
    0
    0.07
    0.21
    
    0.01
    0.01
    
    Fly Ash
    Weight
    %
    1.5708
    0.007
    0.001
    0.0303
    0
    10.1398
    17.5498
    0.0054
    0.0015
    0.017
    1 .4329
    0.0013
    0.0008
    0
    0.8306
    0.0046
    0.0031
    0.4455
    0.0426
    0.0008
    0.0041
    0.0028
    0
    1 .4329
    0
    0.5808
    24.4341
    0.0351
    0.0018
    4.0201
    0
    2.8137
    0.0406
    8.0717
    2.6349
    0.0011
    0.0067
    0.058
    0.0021
    Uncertainty
    0.4755
    0.0218
    0.0023
    0.0655
    0.0154
    1 .7825
    1.5419
    0.001
    0.0128
    0.0013
    0.2009
    0.0018
    0.0033
    0.0164
    0.059
    0.0868
    0.0031
    0.0465
    0.0033
    0.0025
    0.001
    0.0004
    0.2192
    0.1592
    0.0126
    0.2447
    5.0076
    0.0026
    0.0003
    1.2886
    0.0143
    0.2174
    0.0029
    0.6409
    0.1873
    0.0025
    0.0198
    0.0093
    0.0052
    Incinerator
    Weight
    %
    1.15
    0.01
    0
    0.14
    0.01
    2.37
    
    0.02
    0
    0.08
    55.79
    0
    
    0.01
    1.72
    8.43
    14.56
    
    0.04
    27.63
    0.01
    0.01
    5.5
    37.21
    0.02
    0.05
    1.28
    0
    0.01
    4.42
    0.02
    
    0.02
    10.46
    3.16
    
    0.04
    0.11
    
    Uncertainty
    0.83
    0.15
    0.04
    0.55
    0.08
    0.62
    
    0.02
    0.03
    0.1
    27.5948
    0.02
    
    0.1
    0.31
    61.15
    11.69
    
    0.01
    47.27
    0.04
    0
    4.55
    18.03
    0.07
    0.16
    0.86
    0.02
    0.01
    1.82
    0.08
    
    0.01
    2.6
    0.63
    
    0.14
    0.17
    
    December 2009
    A-288
    

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    Residua, Wood Oi| Combustion
    Vanadium V 0.0007 0.005 0.4
    Yttrium Y 0.0001 0.0011 0
    Zinc Zn 0.0762 0.0054 0.01
    Zirconium Zr 0 0.0014 0
    Ammonium NH4+ 0.1132 0.014 0.84
    Sodium ion Na+ 0.11
    Carbonate C03~ 0
    0.04
    0
    0
    0
    0.24
    0.02
    0.0214
    0
    0
    0.02
    0
    0.03
    0
    0.2577
    DE Fly Ash
    0.01 0.0038 0.011
    0 0.0013 0.0021
    0.02 0.031 0.0023
    0 0.0039 0.0008
    0.01 0.0234 0.022
    0.01 4.7518 0.3438
    0.4463
    Incinerator
    0.01 0.07
    0 0.02
    0.57 0.39
    0 0.02
    7.41 7.81
    1.81 2.63
    
    Organic carbon QC2 ?513 „ 66?5
    Organic carbon QC3 8 962? 1 m5
    Organic carbon QC4 2 ?683 1 1919
    EC I EC1 20.342 2.9324
    Chlorine atom CI" 0.2874 0.0404 0.05
    0.01
    0.03
    0.01 27.5797 8.1193
    6.35 10.46
    EC III ECS 2.2878 0.4252
    EC EC 21.1455 4.5813 1.84
    Bromine Atom Br 0.0029 0.0011 0
    0.93
    0
    8.14
    0
    10.01 0 0.1227
    0 0.0441 0.0032
    18.58 20.89
    0.19 0.3
    Organic carbon I OC1 25.1452 4.6648
    ECU EC2 2.9362 1.2422
    Sulfur dioxide S02
    Potassium ion K+ 0.5208 0.0795 0.01
    A.3.3. Receptor Model Results
    0.01
    0
    0.01 14.5473 1.3393
    1.01 0.42
    Source: U.S. EPA SPECIATE database http://www.epa.gov/ttnchie1/software/speciate/index.html
    Table A-56. PM2.6 receptor model results (pg/m3)
    o«m«iin«o;*« Measured PM2 5 Vegetative
    Sampling Site Concentration Burning
    Albany, NY 2000-2001 20.9 5.5
    Birmingham, AL, 2000-2001 16.2 3.3
    Houston, TX, 2000-2001 12.4 3.1
    Long Beach, CA, 2000-2001 30.0 4.6
    Las Vegas, NV, 2000-2001 2.5 1.0
    El Paso, TX, 2000-2001 5.5 0.7
    Wfestbury, NY, 2000-2001 11.5 1.7
    Road
    Dust,
    Soil
    1.9
    1.4
    2.6
    1.3
    2.0
    2.8
    0.7
    (NH4)2S04
    2.4
    3.7
    1.6
    2.1
    0.5
    0.7
    5.2
    NH4N03 Tailpipe ^
    4.6 2.9 0.0
    2.4 5.7 0.0
    2.2 2.6 0.0
    16.3 4.1 0.4
    0.3 1.5 0.0
    0.3 2.0 0.3
    2.2 5.3 0.0
    
                                                                                    Source: Abu-Allaban et al. (2007, 0985751
    December 2009
    A-289
    

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    Table A-57. PMio receptor model results (mass
    Sampling Site
    Apline.CA, 1994-1995
    Apline.CA, 1995
    Apline.CA, 1995
    Atascadero, CA, 1994-1995
    Atascadero, CA, 1995
    Atascadero, CA, 1995
    Lake Arrowhead, CA, 1994-1995
    Lake Arrowhead, CA, 1995
    Lake Arrowhead, CA, 1995
    Lake Elsinore, CA, 1994-1995
    Lake Elsinore, CA, 1995
    Lake Elsinore, CA, 19952
    Lancaster, CA, 1994-1995
    Lancaster, CA, 1995
    Lancaster, CA, 1995
    Lompoc.CA, 1994-1995
    Lompoc.CA, 1995
    Lompoc.CA, 1995
    Long Beach, CA, 1994-1995
    Long Beach, CA, 1995
    Long Beach, CA, 1995
    MiraLoma.CA, 1994-1995
    MiraLoma.CA, 1995
    MiraLoma.CA, 1995
    Riverside, CA, 1994-1995
    Riverside, CA, 1995
    Riverside, CA, 1995
    San Dimas.CA, 1995
    San Dimas.CA, 1995
    Santa Maria, CA, 1994-1995
    Santa Maria, CA, 1995
    Santa Maria, CA, 1995
    Upland, CA, 1994-1 995
    Upland, CA, 1995
    Upland, CA, 1995
    Wood
    Smoke
    15.00
    9.92
    10.97
    44.22
    21.36
    73.45
    6.86
    4.85
    9.91
    12.72
    17.13
    6.84
    22.49
    3.69
    34.89
    
    13.09
    
    10.12
    2.38
    14.32
    4.68
    5.20
    27.97
    14.14
    6.20
    25.28
    7.62
    22.01
    18.66
    12.94
    12.24
    20.33
    7.33
    28.10
    Diesel
    33.19
    58.78
    65.64
    22.16
    38.99
    18.11
    46.55
    65.20
    38.90
    44.01
    74.72
    38.48
    43.14
    46.18
    37.30
    18.16
    51.27
    79.42
    43.24
    70.25
    56.80
    48.87
    53.72
    41.88
    46.67
    52.15
    47.65
    71.35
    61.34
    23.99
    52.57
    48.13
    46.39
    68.69
    46.52
    Gasoline
    Vehicles
    46.46
    11.47
    10.81
    26.44
    12.41
    
    33.92
    7.40
    46.70
    18.61
    
    10.85
    20.56
    12.66
    7.33
    49.65
    14.73
    10.19
    16.49
    5.47
    6.15
    18.10
    6.65
    8.87
    12.03
    7.93
    
    4.87
    4.48
    22.03
    11.87
    10.79
    14.08
    3.50
    4.90
    percent)
    Natural Gas
    Combustion
    
    
    
    
    
    
    2.73
    4.95
    0.79
    
    0.26
    0.21
    0.45
    0.20
    0.61
    
    
    
    0.13
    0.86
    0.72
    
    
    
    
    0.16
    
    0.15
    0.23
    
    0.27
    0.47
    
    0.17
    0.33
    
    Vegetative
    Detritus
    5.31
    19.63
    12.66
    
    17.89
    3.14
    9.85
    17.65
    3.66
    4.21
    7.81
    15.55
    3.73
    8.21
    7.78
    5.89
    20.73
    10.87
    3.97
    6.79
    5.34
    8.82
    18.79
    11.50
    6.83
    14.54
    6.91
    8.35
    3.70
    5.58
    9.63
    18.04
    4.49
    9.19
    10.30
    
    Tire Wear
    Debris
    
    
    
    6.91
    9.43
    5.31
    
    
    
    20.42
    
    28.01
    9.78
    29.17
    11.93
    26.38
    
    
    26.00
    14.11
    16.61
    19.52
    15.71
    9.85
    20.31
    19.06
    20.17
    
    7.85
    8.15
    12.78
    15.05
    14.70
    11.25
    9.81
                                                                                    Source: Manchester-Neesvig et al. (2003, 098102'
    December 2009
    A-290
    

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    A.4.   Exposure Assessment
    
    A.4.1.  Exposure  Assessment Study  Findings
    Table A-58.   Exposure Assessment Study Summaries
    Adar et al. (2007, 098635)
              Study Design
                   Period
                  Location
                Population
               Age Groups
             Indoor Source
           Personal Method
                   Periods
    
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Cohort
    March 2002-June 2002
    St. Louis, Missouri
    Senior citizens exposed to traffic-related PM
    60
    NR
    Samples of FeNO were collected between 8:00 and 9:00 a.m. on the mornings before and after each trip. In the hours
     surrounding these samples, group-level measurements of particle concentrations also were collected using several continuous
     instruments installed on two portable carts. These carts were first positioned in a central location inside the participants' living
     facilities 24-h before each trip. The carts remained at the facilities until it was time for the trips, at which point they followed the
     participants from the health testing room, onto the bus, to the group activity, and to lunch. After the trip home aboard the bus,
     the carts were returned to the central location in the living facility where they remained until the conclusion of the health testing
     on the following morning. Continuous measurements of ambient particles and gases also were collected from a central
     monitoring station in East St. Louis, Illinois. Two portable carts containing continuous air pollution monitors were used to
     measure group-level micro-environmental exposures to traffic  related pollutants, including PM2.5, BC, and size-specific particle
     counts. PM2.s concentrations were measured continuously using a DustTrak aerosol monitor model 8520 with a Nafion diffusion
     dryer. Integrated samples of PM2.5 mass also were collected using a Harvard Impactor for daily calibration of the trip and
     facility.
    Continuous BC concentrations were measured using a  portable aethalometer with a 2.5-um impaction inlet. Particle counts
     were measured using a model CI500 optical particle counter with a modified flow rate of 0.1 cubic feet per minute.
    NR
    PM2.5
    PM2.5, PM10
    BC, pollen and mold also assessed
    PM2.5 exposures resulted in increased levels of FeNO in elderly adults, suggestive of increased airway inflammation. These
     associations were best assessed by microenvironmental exposure measurements during periods of high personal particle
     exposures. In pre-trip samples, both microenvironmental and ambient exposures to PM25 were positively associated with
     FeNO. For example, an interquartile increase of 4 ug/m3 in the daily microenvironmental  PM2.5 concentration was associated
     with a 13% [95% Cl: 2-24)  increase in FeNO. After the  trips, however, FeNO concentrations were associated predominantly
     with microenvironmental exposures, with significant associations for concentrations measured throughout the whole day.
     Associations with exposures during the trip also were strong and statistically significant with a 24% (95% Cl: 15-34)  increase in
     FeNO predicted per interquartile increase of 9 ug/m3 in PM2 5. Although pre-trip findings were generally robust and the post-trip
     findings  were generally robust, the post-trip findings were sensitive to several influential days.
    Adgate et al. (2002, 030676)
              Study Design
                   Period
                  Location
                Population
               Age Groups
             Indoor Source
           Personal Method
             Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Comparison of outdoor, indoor and personal PM25 in three communities.
    April-June, June-August, September-November, 1999
    Battle Creek, East St. Paul, and Phillips, Minnesota, constituting the Minneapolis-St. Paul metropolitan area.
    Adults in urban areas
    Mean age 42 ± 10, range 24-64 yr
    No
    Inertial impactors (PEM) in a foam-insulated bag with shoulder strap with the inlet mounted on the front.
    PM2.5
    PM2.5
    PM2.5
    NR
    The relative level of concentrations report in other studies was duplicated. Outdoor < indoor < personal. On days with paired
     samples (n = 29), outdoor concentrations were significantly lower (mean difference 2.9 ug/m3, p = 0.026) than outdoor at home.
    December 2009
                                          A-291
    

    -------
    Adgate et al. (2007,156196)
               Study Design
                    Period
                   Location
                 Population
              Indoor Source
    
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    NR
    1999-; April 26-June 20, June 21-August 11, September 23-November 21
    Minneapolis-St. Paul metropolitan area
    NR
    Cigarette smoke, resuspension of house dust from carpets, furniture and clothes, and emissions from stoves and kerosene
     heaters (Leaderer et al., 1993; Ferro et al., 2004).
    Personal monitoring was conducted for two consecutive days, and was conducted so that the two 24-h averages matched
     indoor (I) and personal (P) measurements were collected in concert with outdoor (0) samples in each community. Gravimetric
     concentrations for P and I were collected using inertial impactor environmental monitoring inlets and air sampling pumps. To
     obtain I measurements, monitors were placed inside each residence in  a room where the participants reported spending the
     most waking hours. P measurements were obtained by carrying personal pumps in small bags. 0 samples were collected near
     the approximate geographic center of each  neighborhood and monitors ran from midnight to midnight for two consecutive 24-h
     periods, followed by a day to change filters. Gravimetric 0 PM2.5 concentrations were obtained using a federal reference
     method sampler.
    PM2.5
    PM2.5
    PM2.5
    Ag, Al, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, La, Mg, Mn, Na, Ni, Pb, S, Sb, Sc, Ti, Tl, V, Zn
    The relationships among P, I, and 0 concentrations varied across trace elements (TE). Unadjusted mixed-model results
     demonstrated that 0 monitors are more likely to underestimate than overestimate exposure to many of the TEs that are
     suspected to play a role in the causation of air pollution related health effects. These data also support the conclusion that TE
     exposures are more likely to be underestimated in a lower income and centrally located community than in a comparatively
     higher income community. Within the limits of statistical power for this sample size, the adjusted models indicated clear
     seasonal and community related effects that should be incorporated in long-term exposure estimates for this population.
    Adgate et al. (2003, 040341)
               Study Design
                    Period
                   Location
                 Population
                Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Time-series epidemiologic study
    April-November 1999; spring: 26 April-20 June; summer: 21 June-11 August;fall: 23 September-21 November
    Minneapolis-St. Paul, Minnesota
    Healthy non-smoking results
    24-64 yr (mean age 42 ± 10)
    NR
    Personal and indoor gravimetric PM concentrations were collected using PM2.5 inertial impactor environmental monitoring inlets
     and air sampling pumps. Monitors were placed inside each participant's residence in the room where he/she reported spending
     the majority of their waking hours to obtain I measurements. Participants also carried personal pumps in small bags to obtain P
     measurements. Start times for indoor and personal monitors were always within a few minutes of each other. Gravimetric 0
     and central site PM2 5 concentrations were obtained using a federal reference method sampler and EPA site requirements for
     ambient sampling. Gravometric samples were collected near the approximate geographic center of each neighborhood, and
     monitors ran from midnight to midnight for 2 consecutive 24-h periods, followed by a day to change filters.
    NR
    NR
    NR
    NR
    PM2.5 concentrations were higher than I concentrations, which were higher than 0 concentrations. In healthy non-smoking
     adults, moderate median for correlation between P and I; modest median for correlation between I and 0; and minimal median
     correlation between P and 0 longitudinal were observed for PM25 measurements. A sensitivity analysis indicated that
     correlations did not increase if the days with exposures to environmental tobacco smoke or occupational exposures were
     excluded. In the sample population neither P nor I monitors provided a highly correlated estimate of exposure to 0 PM25 over
     time. These results suggest that the studies showing relatively strong longitudinal correlation coefficients between P and 0
     PM2.5 for individuals sensitive to air pollution health effects do not necessarily predict exposure to PM2.5 in the general
     population.
    Allen etal. (2003. 053578)
               Study Design
    
                    Period
                   Location
                 Population
    
                Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
    Use of continuous light scattering data to separate indoor PM into indoor- and outdoor-generated components to enhance
     knowledge of the outdoor contribution to total indoor and personal PM exposures.
    November 1999-May 2001
    Seattle, WA
    Elderly people and children spending most of their time (up to 70%) indoors. The study included healthy elderly subjects, elderly
     with COPD and coronary heart disease (CHD), and child subjects with asthma.
    Age n; 0-29 25; 30-59 36; >60 22; unknown 2
    Suggested (not identified)
    NR. Indoor and outdoor sampling conducted
    NR
    PM2.5
    December 2009
                                            A-292
    

    -------
              Ambient Size  PM2.5
              Component(s)  S
           Primary Findings  A recursive mass balance model can be successfully used to attribute indoor PM to its outdoor and indoor components and to
                             estimate an avg Penetration, air exchange rate, deposition rate, and NH4+for each residence.
    Allen etal. (2007.154226)
                    Period
                   Location
                 Population
                Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Heating seasonOctober-February; Non-heating season March-September
    Seattle, WA
    NR
    NR
    NR
    Indoor and outdoor PM2.5was measured using a 10-l/min single-stage Harvard Impactor (HI) with 37-mm Teflon filters. The
     relationship between particle mass concentration and light scattering coefficient (bsp) was also measured on a continuous
     basis indoors and outdoors using nephelometers (model 902 and 903).
    NR
    PM2.5
    PM2.5
    S (measured by XRF)
    The authors showed that RM can reliably estimate Finf. Simulation results suggest that the RM Finf estimates are minimally
     impacted by measurement error. In addition, the average light scattering response per unit mass concentration was greater
     indoors than outdoors. Results show that the RM method is unable to provide satisfactory estimates of the individual
     components of Finf. Individual homes vary in their infiltration efficiencies, thereby contributing to exposure misclassification in
     epidemiologic studies that assign exposures using ambient monitoring data. This variation across homes indicates the need for
     home-specific estimation methods, such as RM or S, instead of techniques that give average estimates of infiltration across
     homes.
    Annesi-Maesano et al. (2007,093180)
               Study Design
                    Period
                   Location
                 Population
                Age Groups
              Indoor Source
           Personal Method
    
              Personal Size
      Microenvironment Size
               Ambient Size
              Component(s)
           Primary Findings
    Population based
    March 1999 to October 2000
    Bordeaux, France; Clermont-Ferrand, France; Creteil, France; Marseille, France; Strasbourg, France; Reims, France
    School children
    10.4±0.7yr
    NR
    PM2.5 was monitored simultaneously in both schoolyards (proximity level) and fixed-site monitoring stations (city level) using
     4L/min battery operated pumps attached to polyethylene filter sampling cartridges.
    NR
    NR
    PM2.5
    NR
    Results show an increased risk for EIB and flexural dermatitis at the period of the survey, past year atopic asthma and SPT
     positivity to indoor allergens in children exposed to high levels of traffic-related air pollution (PM2 5 concentrations exceeding
     10 ug/m3). Population based findings are also consistent with experimental data that have demonstrated that inhalation of
     traffic-related air pollutants either individually or in combination,  can enhance the immune responses and airway response to
     inhaled allergens, such as pollens or house dust mites, in atopic subjects.
    Balasubramanian and Lee (2007,156248)
               Study Design
                    Period
                   Location
                 Population
                Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
               Ambient Size
           Primary Findings
    Case study of 3 rooms of 1 flat on the 8th floor, and "outside the home."
    May 12-23, 2004
    Singapore
    Residents of an urban area in a densely populated country.
    NR
    Time-activity logs identified tobacco smoking, cooking, household cleaning and general resident movements.
    NR
    NR
    PM2.5
    PM2.5
    I/O suggest that chemicals such as CI", Na+, Al, Co, Cu, Fe, Mn, Ti, V, Zn, and EC were derived from the migration of outdoor
     particles (I/O  <1 or~1).
    December 2009
                                            A-293
    

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    Barn et al.  (2008,156252)
              Study Design
    
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Measure indoor Fu of PM2.5 from forest fires/wood smoke, effectiveness of high-efficiency particulate air (HEPA) filter air
     cleaners in reducing indoor PM2.5, and to analyze the home determinants of Finf and air cleaner effectiveness (ACE).
    2004-2005 (summer 2004 and 2005, winter 2004)
    British Columbia, Canada
    Homes affected by either forest fire smoke or residential wood smoke
    NR
    NR
    Personal Data RAM for ambient air sampling
    Indoor home PM25
    NR
    Outdoor home PM25
    NR
    Use of HEPA filter air cleaners can dramatically reduce indoor PM25 concentrations. Number of windows and season predict Finf
     (p< 0.001).
    Baxter et al. (2007, 092726)
              Study Design
    
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
    
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Part of a prospective birth cohort study performed by the Asthma Coalition for Community, Environment, and Social Stress
     (ACCESS)
    2003-2005. Non-heating season: May to October; Heating season: December to March
    Boston (urban)
    Lower socio-economic status (SES) households
    NR
    NR
    PM2.5 samples were collected with Harvard personal environmental monitors (PEM). NO concentrations were measured using
     Yanagisawa passive filter badges.
    NR
    PM2.5
    PM2.5
    EC
    The authors' regression models indicated that PM2.5 was influenced less by local traffic but had significant indoor sources, while
     EC was associated with local traffic and N02 was associated with both traffic and indoor sources. However, local traffic was
     found to be a larger contributor to indoor N02 where traffic density is high and windows  are opened, whereas indoor sources
     are a larger contributor when traffic density is low or windows are closed. Similarly, traffic contributed up to 0.2 |ig/m3 to indoor
     EC for homes with open windows, with an insignificant contribution for homes where windows were closed.; Comparing models
     based on p-values and using a Bayesian approach yielded similar results, with traffic density volume within a 50 m buffer of a
     home and distance from a designated truck route as important contributors to indoor levels of N02 and EC, respectively.
     However, results from the Bayesian approach also suggested a high degree of uncertainty in selecting the best model. The
     authors concluded that by utilizing public databases and focused questionnaire data they could identify important predictors of
     indoor concentrations for multiple air pollutants in a high-risk population.
    Baxter et al. (2007, 092725)
              Study Design
                    Period
                  Location
                 Population
              Indoor Source
    
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
              Copollutant(s)
           Primary Findings
    Simultaneous indoor and outdoor samples taken in 43 low SES homes in heating and non-heating seasons. Homes were
     selected from a prospective birth cohort study of asthma etiology (n = 25). Non-cohort homes were in similar neighborhoods
     (n = 18).
    2003-2005
    Boston, Massachusetts
    Lower SES populations in urban areas
    Home type, year built, tobacco smoke, opening windows, time spent cooking, use of candles or air freshener, cleaning activities,
     air conditioner use.
    NR
    NR
    PM2.5
    NR
    EC (m-1 x 10"5); Ca (ng/m3); Fe (ng/m3); K (ng/m3); Si (ng/m3); Na (ng/m3); Cl (ng/m3); Zn (ng/m3); S (ng/m3); V (ng/m3)
    N02
    The effect of indoor sources may be more pronounced in high-density multi-unit dwellings. Cooking times, gas stoves, occupant
     density and humidifiers contributed to indoor pollutants.
    December 2009
                                            A-294
    

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    BeruBe et al. (2004, 007894)
              Study Design
                    Period
                  Location
                 Population
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
                         6 homes in Wales and Cornwall were monitored four times per year, inside samples in the living areas and outside the home.
                         NR but < 2003
                         Wales and Cornwall, UK
                         Urban, suburban, and rural homes
                         ETS, pets, cleaning, traffic load
                         NR
                         NR
                         PM10
                         NR
                         NR
                         There are greater masses of PMio indoors, and that the composition of the indoor PM10 is controlled by outdoor sources and to
                          a lesser extent by indoor anthropogenic activities, except in the presence of tobacco smokers. The indoor and outdoor PMio
                          collected was characterized as being a heterogeneous mixture of particles (soot, fibers, sea salt, smelter, gypsum, pollen and
                          fungal spores).
    Branis et al. (2005,156290)
            Study Design
                  Period
                Location
              Population
             Age Groups
            Indoor Source
    
         Personal Method
            Personal Size
    Microenvironment Size
            Ambient Size
           Component(s)
         Primary Findings
                            Human exposure assessment in a university lecture hall
                            Oct. 8, 2001-Nov. 11,2001
                            Prague, Czech Republic
                            University students
                            NR
                            Presence of people identified as a source of coarse particles ; outdoor air identified as a source of indoor fine particles (PMi 0
                            and PM2.5)
                            Harvard impactors (HI) with membrane Teflon filters
                            PM,, PM15, PM10
                            PMi, PM2.5, PM10
                            PM^
                            NR
                            Presence of people is an important source of coarse particles indoors ; Outdoor air may be an important source of fine indoor
                            particles.
    Brunekreef et al. (2005, 090486)
    
              Study Design   Exposure assessment
                    Period   Winter and spring 1 998-1 999
                   Location   Amsterdam and Helsinki
                 Population   Elderly
               Age Groups   50-84 yr
              Indoor Source   NR
           Personal Method   Amsterdam Gillian with made to fit bags with belt with GK2.05 cyclone samplers 4L/min; Helsinki BGI with shoulder strap or
                            backpack with GK2.05 cyclone samplers 4 L/min.
              Personal Size   PM2.5
      Microenvironment Size   PM2.5
              Ambient Size   PM2.5
              Component(s)   S042"
           Primary Findings   In both cities, personal and indoor PM2.5 were highly correlated with outdoor concentrations.
    Chillrud et al. (2004, 054799)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
                         Repeated measures on a cohort of high school students in New York City
                         Summer and winter of 1999 (eight weeks each)
                         Manhattan, Bronx, Queens, Brooklyn, NY
                         Persons traveling the subway
                         14-1 Syr
                         No
                         Sampling packs carried by subjects
                         PM2.5
                         PM2.5 (home indoor and home outdoor)
                         PM2 5. Urban fixed-site and upwind fixed site operated for three consecutive 48-h periods each week.
                         Elemental Fe, Mn,and Crare reported in this study out of 28 elements sampled.
                         Personal samples had significantly higher concentration of Fe, Mn, and Cr than home indoor and ambient samples. The ratios
                          of Fe (ng/ug of PM2.5) vs Mn (pg/ug PM2.5) showed personal samples to be twice the ratio for crustal material. Similarly for the
                          Cr/Mn ratio. The  ratios and strong correlations between pairs of elements suggested steel dust as the source. Time-activity
                          data  suggested subways as a source of the elevated personal metal levels.
    December 2009
                                                                 A-295
    

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    Conner and Williams (2004,156364)
    
              Study Design  This is part of the EPA Baltimore PM Study of the Elderly.
                    Period  July-August, 1998
                  Location  Towson, Maryland
                Population  65+ adults
               Age Groups  65+ yr
              Indoor Source  Personal sampling devices (PEM)
           Personal Method  PM2.5
              Personal Size  PM2.5
      Microenvironment Size  NR
              Ambient Size  NR
          Primary Finding(s)  A greater variety of particles was observed in the personal samples compared to the fixed-location apartment samples.
    Cortez-Lugo et al. (2008,156368)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
    
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Cohort
    Feb-Nov 2000
    Mexico City, Mexico
    Ambulatory adults with moderate to severe COPD, active smokers excluded
    Adults
    carpeting, aerosol sprays used, boiler use and location, animals, mold, tobacco smoking, windows closed
    Personal pumps with 37-mm Teflon filters, flow rate 4 l/min in a bag with shoulder strap. The impactor was near the breathing
     zone
    PM2.5
    PM25,PMio
    PM25,PM10
    NR
    Indoor PM25 concentrations explained 40% of the variability of personal exposure. The best predictors of personal exposure
     were indoor contact with animals (12%), mold (27%), being present during cooking (27%), and aerosol use (17%).
    Crist et al. (2008,156372)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Indoor, outdoor, and personal monitoring
    January 1999-August 2000
    Ohio
    Fourth & fifth-grade children
    9-11 yr old
    Filter,  portable pump
    Filter,  PM2.5
    Indoor school; Filter, PM2.s
    Outdoor school; Filter, PM25
    PM2.5
    NR
    Higher correlation was observed between P and I compared with the correlation between either P and ambient (A) or I and A.
    Delfino et al. (2004, 056897)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Copollutant(s)
           Primary Findings
    Panel study with repeated measures
    Sep-Oct 1999 or Apr-Jun 2000
    Alpine, California
    Children
    9-17 yr
    No
    Personal dataRAM (pDR) carried at waist level using a fanny pack, shoulder harness, or vest.
    0.1-10 urn
    PM10 and PM2 5; measured immediately outside the house and in the living room of the home.
    PM10
    03 and N02 measured at central site
    Percent  predicted FEV, was inversely associated with personal exposure to fine particles. Also with indoor, outdoor and central
     site gravimetric PM2.5, PM10, and with hourly TEOM PM10.
    December 2009
                                           A-296
    

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    Delfino et al. (2006, 090745)
              Study Design
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
    
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
                 Cohort. Measured daily expired NO (FeNO)
                 Aug-Dec 2003
                 Riverside and Whittier, California
                 Children with asthma exacerbations in previous 12 months, non-smokers, non-smoking households
                 9-1 Syr
                 No
                 Wore a backpack during waking hours for PM2.5, EC and OC, N02, temperature, and relative humidity. Exhaled air collected in
                  Mylar bags to analyze for NO.
                 24-h PM25; 1-h max PM25; 8-h max PM25; 24-h N02
                 NR
                 24-h PM25; 24-h PM10; 8-h max 03; 8-h max N02; 24-h N02; 8-h max CO
                 24-h PM15 EC; 24-h PM2.5OC
                 The strongest positive associations were between FeNO and 2-day average pollutant concentrations. Per IQR increases 1.1
                  ppb FeNO/24 ug/m3 personal PM2.5.; 0.7 ppb FeNO/0.6 ug/m3 personal EC; 1.6 ppb FeNO /17 ppb personal  N02 Ambient
                  PM2.5 and personal and ambient EC were significant only when subjects were taking inhaled corticosteroids. Subjects taking
                  both  inhaled steroids and antileukotrienes had no significant associations. Distributed lag models showed personal PM25 in the
                  preceding 5 h was associated with FeNO.
    Diapouli et al. (2007,156397)
              Study Design
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
                  Exposure assessment. Sampling of schools, residence, private vehicle
                  Schools-11/2003-02/2004 and 10/2004-12/2004.; Residence-10/2004; Vehicle-10/204-12/2004
                  Athens, Greece
                  Primary school children
                  NR
                  NR
                  Handheld portable Condensation Particle Counters (TSI, Model 3007) were used for all sampling locations. Primary schools
                  indoor measurements were primarily conducted inside classrooms, at table height. However, at three of the schools, rooms of
                  different uses were selected. These included a teachers' office (where smoking was permitted), a computer day lab (used by
                  students only part of the day), and a library and gymnasium (where intense activity took place almost all day long). Outdoor
                  measurements took place in the yard of each school. Residence samples were taken in a bedroom at breathing height and on
                  the terrace, for indoor and outdoor samples, respectively. In-vehicle samples were taken by placing the CPC 3700 on the
                  passenger seat while the vehicle drove along predetermined routes.
                  NR
                  0.01-1 urn
                  0.01-1 urn
                  NR
                  The results showed that children attending primary schools in the Athens area are exposed to significant PM concentration
                  levels, both indoors and outdoors. Vehicular emissions seem to be a major contributor to the measured outdoor concentration
                  levels at the studied sites. Indoor PM concentrations appeared to be influenced by both vehicular emissions and indoor
                  sources including cleaning activities, smoking,  a high number of people in relation to room volume and furniture material (i.e.,
                  carpet). UFPs concentrations diurnal variation, both outside the schools and the  residence, supports the close relation  of UFPs
                  levels with traffic density. Indoor concentrations within schools exhibited variability during the school day only when there were
                  significant  changes in room occupancy. 24-h variation of indoor concentrations at the residence were well correlated with the
                  outdoor concentration (R2 = 0.89).
    Diapouli et al. (2008,190893)
    Study Design   Indoor, outdoor air monitoring of PM. To determine children exposure in school environment. To evaluate relationship between
                  indoor and outdoor levels.
                  Athens, Greece
                  Primary schools
                  NR
                  Indoor PMi, PM2.5, PM10, presence of children and activities of children in classrooms, infiltrated vehicular exhaust
                  Harvard PEM, Teflon filters Dust Trak Condensation particle counter
                  NR
                  PM^PMzs, PM10
                    Period
                   Location
                 Population
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
                  N03", S042"
                  High levels of PMio and PM2.5 measured indoors and outdoors. PMio more variable spatially than PM2.5. I/O ratio for PMio and
                  PM2.5 close to 1 at almost all sites. Ratio of PMi smaller than 1 in all cases. Vehicular traffic presumed to be the main source of
                  PM,. Indoor PM2.5 and PM10 levels dependent on the amount of activity in classroom and outdoor levels. Indoor S042~
                  concentrations strongly associated with outdoor levels. Result suggests that S042~ can be used as a proper surrogate for
                  indoor PM of outdoor origin.
    December 2009
                                                          A-297
    

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    Ebeltetal. (2005. 056907)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Personal exposure assessment related to health outcomes for a sensitive sub-population
    Summer 1998
    Vancouver, British Columbia, Canada
    16 persons who had COPD
    Mean subject age 74 yr, Range 54 to 86
    Separated total personal exposure into "ambient" and "non-ambient" based on sulfate results and modeling.
    24-h integrated filter sample
    PM2.5
    PM2.5, PM10, PM10.2.5
    PM25, PM10, PM10.25
    S042'
    Ambient exposures and (to a lesser extent) ambient concentrations were associated with health outcomes. Total and
     nonambient particle exposures were not.
    Farmer et al. (2003, 089017)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Case control molecular epidemiology studies of carcinogenic environmental pollutants, particularly PAHs
    12 months
    Prague, Czech Republic (2 sites); Kosice, Slovak republic; Sofia, Bulgaria
    Policeman and busdrivers usually working through busy streets in 8-10 h shifts and a control population.
    Variable, range not stated
    NR
    Personal Monitoring Devices; Blood and Urine Samples; Stationary Versatile Air Pollution Samplers (VAPS)
    PM10
    NR
    PM10; PM2.5 (not  reported)
    Extractable organic matter (EOM), B[a]P, c-PAHs
    EOM per PM^was at least 2-fold higher in winter than in summer, and c-PAHs over 10-fold higher in winter than in summer.
     Personal exposure to B[a]P and to total c-PAHs in Prague ca. was 2-fold higher in the exposed group compared to the control
     group, in Kosice ca. 3-fold higher, and in Sofia ca. 2.5-fold higher.
    Ferro et al. (2004,  055387)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Case study, 1 home
    Redwood City, California
    NR
    NR
    NR
    Co-located real-time particle counters and integrated filter samplers (Met-One Model 237B) were used to measure personal
     (PEM), indoor (SIM) and outdoor (SAM) PM concentrations. The PEM was attached to a backpack frame and worn by the
     investigator while performing prescribed activities. The SIM was attached to a six foot step-ladder with the intake at breathing
     height. The SAM was located under a two-sided roofed shed in the backyard of the home with the filter samplers supported by
     a metal stand and the real-time particle counters sitting on a table.
    PM5
    PM25;PM5
    PM25;PM5
    NR
    The results of this study indicate that house dust resuspended from a range of human activities increases personal PM
     concentrations and this resuspension effect significantly contributes to the personal cloud. The results of this study also
     suggest that normal human activities that resuspend house dust may contribute significantly to the strong correlations found
     between personal exposure and indoor PM concentrations in previous studies. The PEM/SIM ratios for human activity
     presented in this paper are also in the range of those reported by previous studies.
    December 2009
                                            A-298
    

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    Gadkari and Pervez (2007,156459)
              Study Design
    
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Evaluation of relative source contribution estimates of various routes of personal RPM in different urban residential
     environments.
    Summer 2004 (March 15-June 15)
    Chattisgarh, India
    All likely. Not specified
    21-61 yr, average age 40 ± 15 yr
    No
    Personal respirable dust samplers (RDS) with GFF
    RPM
    NR
    RPM
    Fe, Ca, Mg, Na K, Cd, Hg, Ni, Cr, Zn, As, Pb, Mn and Li
    Authors concluded that "(1) indoor activities and poor ventilation qualities are responsible for major portion of high level of
     indoor RPM, (2) majority of personal RPM is greatly correlated with residential indoor RPM, (3) time-activity diary of individuals
     has much impact on relationship investigations of their personal RPM with their respective indoor and ambient-outdoor RPM
     levels; as  reported in earlier reports and (4) residential indoors, local  road-traffic and soil-borne RPMs are the dominating
     routes of personal exposure compared to ambient outdoor RPM levels."
    Gauvin et al. (2002, 034893)
              Study Design
                    Period
                  Location
                 Population
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Fine particle exposure assessment for children in French urban environments, part of VESTA study
    March 1998-December2000
    Paris, Grenoble, Toulouse, France
    Children aged 8-14 yr
    ETS from mother, rodents at home.
    SKC pump 4 Lpm with PM2 5 inlet and 37 mm, 2 micron Teflon filter
    PM2.5
    NR
    PM10
    NR
    The final model explains 36% of the between subjects variance in PM25 exposure, with ETS contributing more than a third to
    this.
    Graney et al. (2004, 053756)
              Study Design
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    The study was designed to assess the trace metal quantification abilities of several analytical methods to measure the total as
     well as soluble amounts of metals with PM2.5 collected from indoor and PM samples. (X-ray fluorescence and instrumental
     neutron activation analysis)
    Retirement facility in Towson, Maryland
    Retirement facility with subjects who spent 94% of their time indoors
    Mean age = 84 yr
    NR
    Measured using personal exposure monitors (MSP Inc) with nozzle to remove particles > 4 urn
    PM2.5
    PM2.5
    NR
    42 elements were analyzed for in the PM2 5 samples collected from personal and well as indoor samples
    Most of the extractable components of the metals were in a water-soluble form suggesting a high potential for bioavailability of
     elements from respiratory exposure to PM25. Based on comparison of trace metals in central I site vs. P samples, resident
     activities result in exposure to higher concentration of soluble trace metals.
    December 2009
                                            A-299
    

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    Haverinen-Shaughnessy et al. (2007,156526)
              Study Design
                    Period
                  Location
                Population
               Age Groups
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
    
           Primary Findings
    Cross-sectional
    Winter, year not reported
    Eastern Sweden
    Elementary school teachers
    NR
    Button inhalable aerosol samplers
    Particle mass
    Particle mass
    NR
    Absorbance coefficient/m x 10"5; Total fungi (spores/m3); Total bacteria (cells/m3); Viable fungi MEA (CFU/m3); Viable fungi
     DG18 (CFU/m3); Viable bacteria (CFU/nf)
    The recall period of 7 days provided the most reliable data for health effect assessment. Both personal exposure and
     concentrations of pollutants at home were more frequently associated with health symptoms than work exposures.
    Ho et al. (2004, 056804)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
    
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Human exposure assessment
    25 Sept. 2002 to 8 March 2003
    Hong Kong
    Occupied buildings located near major roadways
    NR
    Yes. Regression of indoor versus outdoor concentrations of OC and EC revealed an indoor source of OC not present for EC,
     presumably due to such activities of cooking, smoking, and cleaning.
    Co-located mini-volume samplers (flow rate 5 L/min) and Partisol model 2000 sampler with 2.5 |im inlet. All samples on 47 mm
     Whatman quartz microfiber filters, weighed on an electronic microbalance. Analyzed for OC and EC using DRI Model 2001
     Thermal/Optical Carbon Analyzer.
    PM2.5
    NR
    PM2.5
    OC,EC,OM,TC
    The major source of indoor EC, OC, and PM2.5 appears to be penetration of outdoor air, with a much greater attenuation in
     mechanically ventilated buildings.
    Hoek et al. (2008,156554)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Exposure assessment, characterizing indoor/outdoor particle relationships
    October 2002-March 2004
    4 European cities Amsterdam, Athens, Birmingham, Helsinki
    Urban populations
    NR
    Smoking, candle burning, cooking/frying
    No personal exposure assessment was conducted
    NR
    PM10, PM25, PM10-25, Ultrafine (UFP)
    PM10, PM2.5, PM10-2.5, UFP
    soot, sulfate
    Correlation between 24-h average central site and indoor concentrations was lower for UFP than for PM2.5, soot, or S042",
     probably related to greater losses during infiltration due to smaller particle size. Infiltration factors for UFP and PM2.5 were low.
    Hopke et al. (2003, 095544)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Exposure assessment
    26 July to 22 August 1998
    Retirement facility in Towson, MD
    Elderly residents
    Mean age of 84
    Ammonium sulfate and ammonium nitrate, secondary sulfate, OC, and motor vehicle exhaust
    Inertial impactor PEM in the breathing zone of the subjects
    PM2.5
    PM2.5
    PM2.5
    S042'
    Personal exposures were influenced by a combination of indoor and outdoor factors. Indoor factors included gypsum, personal
     grooming products, and  an unknown indoor source. Outdoor factor included S042", soil, and an unknown factor. Outdoor
     factors accounted for 63% of personal exposure, and S042- was the largest ambient contributor to personal exposure (48%).
    December 2009
                                           A-300
    

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    Jacquemin et al. (2007,156600)
    
              Study Design  Assessment of relationship between outdoor and personal concentrations of PM2 5 absorbance and sulfur among post-
                            myocardial infarction patients
                    Period  January 2004-June 2004
                  Location  Barcelona, Spain
                           Survivors of a myocardial infarction exposed to ETS
                           n = 38, including 32  and 15 over age 64.
                           ETS
           Personal Method  Personal samplers (BGI GK2.05 cyclones and battery operated BGIAFC400S pumps)
              Personal Size  PM25
                           NA
                           PM2.5
                           S
           Primary Findings  Ambient measurements of light extinction and S can be used as surrogates to personal PM2.5 exposure, especially for those
                            exposed to ETS.
              Population
             Age Groups
           Indoor Source
    Microenvironment Size
            Ambient Size
           Component^
    Janssen et al. (2005, 088692)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
    
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
                         Panel Study
                         Amsterdam 11/2/1998-6/18/1999; Helsinki 11/1/1998-4/30/1999
                         Amsterdam, The Netherlands; Helsinki, Finland
                         Elderly Cardiovascular Patients
                         50-84 yr
                         No
                         Personal PM25 GK2.05; cyclones; indoor & outdoor Harvard Impactors; Reflectance EEL 43 reflectometers; Elemental
                          Composition Tracer Spectrace 5000 ED-XRF system
                         PM2.5
                         PM2.5
                         PM2.5
                         Estimated EC, elemental composition of a subset of personal, indoor and outdoor samples
                         For most elements, personal and indoor; concentrations were lower than and highly correlated with outdoor concentrations. The
                          highest correlations (median r = 0.9) were found for sulfur and particle absorbance (EC), which both represent fine; mode
                          particles from outdoor origin. Low correlations were observed for elements that represent the coarser part of the PM25 particles
                          (Ca,Cu,Si, CI").
    Jedrychowski et al. (2006,156606)
    
              Study Design   Prospective cohort
                    Period   11/2000-3/2003
                  Location   Krakow, Poland
                Population   Non-smoking pregnant women
               Age Groups   Yes
           Personal Method   Personal Exposure Monitor Sampler (PEMS, Harvard; School of Public Health)
                            PM2.5
                            NR
                            PM10
                            NR
           Primary Findings   The contribution of the background ambient PM10 level was a very strong determinant of the total personal exposure to PM2.5,
                            and it explained about 31% of variance between the subjects.
            Personal Size
    Microenvironment Size
            Ambient Size
           Component(s)
    Johannesson et al. (2007,156614)
    
              Study Design  Cohort
                    Period  Spring and fall seasons of 2002 and 2003
                  Location  Gothenburg, Sweden
                Population  General adult population
               Age Groups  23-51 yr
              Indoor Source  NR
           Personal Method  Fine particles were measured for 24 h using both personal and stationary monitoring equipment. Personal monitoring of PM2 5
                            and PMi was carried out simultaneously with parallel measurements of PM2.5 and PMi indoors in living rooms and outside the
                            house on a balcony, porch, etc. In addition, urban background PM25 levels were measured. Personal monitoring was
                            performed in two ways. The 20 randomly selected subjects carried personal monitoring equipment for PM2.5 only, while the 10
                            staff members carried two pieces of personal monitoring equipment at the same time. On the first measuring occasion, the staff
                            members carried one PM2.5 cyclone and one PMi cyclone. On the second occasion, duplicate monitors for PM2.5 were used.
                            For personal and residential monitoring, the BGI Personal Sampling Pump was used together with the GK2.05 cyclone for
                            PM2.5 sampling and the Triplex cyclone SCC1.062 for PMisampling. The personal sampling pump was placed in a small
    December 2009
                                                                A-301
    

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              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
     shoulder bag and the cyclone attached to the shoulder strap near the subject's breathing zone. The personal monitoring
     equipment was carried by the subject during awake time. During the night, it was placed in the living room. For indoor
     monitoring in living rooms, cyclones (PM2.5 and PMi) were placed at about 1.5 m above the floor. The same setup was used for
     residential outdoor monitoring. The urban background monitor was  placed on top of a roof somewhat south of the city center
     but not near any major highway.
    PM^PM,
    PMjslPM,
    PM25IPM,
    BS
    Personal exposure of PM2.5 correlated well with indoor levels, and the associations with residential outdoor and urban
     background concentrations were also acceptable. Statistically significantly higher personal exposure compared with residential
     outdoor levels of PM2.5 was found for nonsmokers. PMi made up a  considerable proportion (about 70-80%) of PM2.5. For BS,
     significantly higher levels were found outdoors compared with indoors, and levels were higher outdoors during the fall than
     during spring. There were relatively low correlations between particle mass and BS. The urban  background station provided a
     good estimate of the residential outdoor concentrations of both PM2.5 and BS2.5 within the city.  The  air mass origin affected the
     outdoor levels of both PM2.5 and BS2.5; however, no effect was seen on personal exposure or indoor levels.
    Kaur et al. (2005, 086504)
              Study Design
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Exposure assessment, evaluation of exposures between modes of transport, routes, timing
    April 28-May 23, 2003
    Street canyon intersection in Central London, UK
    Users of an urban street canyon intersection
    NR
    NR
    PM2.5 measured usnig high-flow gravimetric personal samplers (PM2.5) operating at a flow rate of 16 l/min carried in a backpack
     with sampling head positioned in personal breathing zone. UFP measured using TSI P-TRAK particle counters in which
     isopropyl alcohol condenses to form droplets that can be easily counted by a photodetector as they pass through a laser beam.
    PM25, UFP (0.02-1 .Oum)
    PM25, UFP (0.02-1 .Oum)
    PM2.5
    NR
    Personal exposures to  PM2.5 while walking were significantly lower then while riding in a car or taxi, likely a function of greater
     distance to roadside. No significant differences in PM2 5 were observed between exposures on the high traffic road compared
     with the backroad. Personal exposure levels were lowest during midday measurements for PM2.5 and highest in the early
     evening. Personal exposures to ultrafine particles were lowest while walking and highest while riding  the bus. Exposures to
     ultrafine particles were also significantly higher on the high traffic road and during morning measurements. Exposure to
     ultrafine particles were highest in the morning, likely the result of  peak traffic density in the morning. Exposure assessment also
     revealed that the background and curbside monitoring stations were not representative of the personal exposure of individuals
     to PM2.5 and CO at and around a street canyon intersection.
    Kaur et al. (2005, 088175)
              Study Design
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Personal exposure assessment of pedestrians walking along high-traffic urban road
    April 19, 2004-June 11, 2004
    Central London, UK
    Pedestrians
    NR
    NR
    PM2 5 gravimetric filter measurement, UFP (0.02-1 urn) P-TRAK device, reflectance reflectometer measurement of PM25 filter
    PM25, UFP (0.02-1 urn)
    NR
    PM2.5, UFP (0.02-1 urn)
    Absorbance of PM2.5 filter
    PM2.s pedestrian exposure was well correlated with and above background fixed-site monitoring levels. PM pedestrian exposure
     was influenced by proximity to curbside and the side of the road walked on.
    December 2009
                                             A-302
    

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    Kim et al. (2005,156640)
    
              Study Design  Panel study
                    Period  8/1999-11/2001
                  Location  Toronto, Canada
                Population  Cardiac-compromised patients
               Age Groups  Mean age 64 yr
             Indoor Source  Gas range (68%); indoor grill (11%); outdoor barbeque (30%); Gas heating fuel (68%); Oil heating fuel (7%)
           Personal Method  Rupprecht and Patashnick ChemPass Personal Sampling System
             Personal Size  PM2.5
      Microenvironment Size  NR
              Ambient Size  PM2.5
             Component(s)  NR
           Primary Findings  Personal PM2.5 exposures were higher than outdoor ambient levels. Personal PM2.5 exposures levels were correlated with
                            ambient levels, mean r = 0.58
    
    
    
    Koistinenetal. (2004.156655)
    
              Study Design  Representative  Population-based study
                    Period  Oct1996-Dec1997
                  Location  Helsinki, Finland
                Population  Non-smoking adults not exposed to environmental tobacco smoke.
               Age Groups  Adults 25-55 yr
             Indoor Source  Soil from outdoors, cooking, smoking, aerosol cleaners, sea salt, combustion sources
           Personal Method  Integrated 24-h filter sample
             Personal Size  PM2.5
      Microenvironment Size  PM2.5
              Ambient Size  PM2.5
             Component(s)  BS
           Primary Findings  Population exposure assessment of PM25, based on outdoor fixed-site monitoring, overestimates exposures to outdoor sources
                            like traffic and long-range transport and does not account for the contribution of significant indoor sources.
    
    
    
    Kousaetal. (2001. 025270)
    
              Study Design  Population based exposure assessment
                    Period  October 1996 to June 1998
                  Location  Helsinki, Finland; Basel, Switzerland; Prague, Czech Republic; Athens, Greece
                Population  Adult urban populations
               Age Groups  25-55 yr
             Indoor Source  Sometimes ETS
           Personal Method  Integrated 48-h filter sample
             Personal Size  PM2.5
      Microenvironment Size  PM2.5
              Ambient Size  PM2.5, PM10
             Component(s)  NR
           Primary Findings  Throughout the study, the highest correlations were those between personal exposures and indoor concentrations, which
                            suggests that indoor sources were important.  Correlations were generally lower between ambient concentrations and personal
                            exposures.
    December 2009
    A-303
    

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    Koutrakis et al. (2005, 095800)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Panel study
    Baltimore 6/28/98-8/22/98 (summer), 2/1/99-3/16/99 (winter); Boston 6/13/99-7/23/99 (summer), 2/1/00-3/12/00 (winter)
    Baltimore, MD Boston, MA
    Healthy older adults, children, adults with COPD
    Children 9-13y/o; Seniors 65+y/o
    NR
    Personal exposure samples of PM25; were collected using a specially designed multipollutant sampler (Demokritou et al. 2001).
     PM2.s was collected using personal environmental monitors (PEMs) and 37-mm; Teflon filters (Teflo, Gelman Sciences, Ann
     Arbor Ml).
    PM2.5
    NR
    PM2.5
    EC, S042"
    Ambient PM25 and S042~ are strong predictors of respective personal exposures. Ambient S042~ is a strong predictor of
     personal exposure to PM25. Because PM25 has substantial indoor sources and S042~ does not, the investigators; concluded
     that personal exposure to S042~ accurately reflects exposure to ambient PM25 and therefore the ambient component of
     personal exposure to PM2.5 as well.
    Lai et al. (2004, 056811)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
    
           Primary Findings
    Personal exposure study
    December 1998-February 2000
    Oxford, UK
    Adults
    25-55 yr(avg = 41)
    Cooking, active smoking, passive smoking heating by gas heater
    Integrated  48-h filter samples
    PM2.5
    PM2.5
    PM2.5
    Ag, Cr, Mn, Si, Al, Cu, Na, Sm, As, Fe, Ni, Sn, Ba, Ga, P, Sr, Br, Ge, Pb, Ti, Ca, Hg, Rb, Tl, Cd, I, S, Tm, Cl, K, Sb, V, Co, Mg,
     Se.Zn.Zr
    Personal exposures were  influenced by both indoor and ambient sources, and indoor levels exceeded ambient levels for PM25
     as well as for VOCs and eight other compounds. Correlation between personal and indoor PM2.5 was 0.60 (p < 0.001).
    Larson et al. (2004,098145)
              Study Design
                    Period
                  Location
                Population
               Age Groups
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Time-series epidemiologic study
    Sep26,2000-May25,2001
    Seattle, Washington
    "Susceptible Populations"
    Time-activity diary
    Harvard Personal Environmental Monitor
    PM2.5
    PM2.5 outside subject's residence, and inside residence
    PM2.5 at Central outdoor site (downtown Seattle)
    Light absorbing carbon (LAC) and trace elements
    Five sources of PM2 5 identified vegetative burning, mobile emissions, secondary sulfate, a source rich in chlorine, and crustal-
     derived material. The burning of vegetation (in homes) contributed more PM25 mass on average than any other sources in all
     microenvironments.
    December 2009
                                            A-304
    

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    Li et al. (2003,047845)
              Study Design
    
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
    
              Personal Size
      Microenvironment Size
           Primary Findings
    Concurrent 10-min avg indoor and outdoor concentrations of PM10 and PM2.5 were recorded for 2 days each in 10 homes with
     swamp coolers
    Summer 2001
    El Paso, Texas
    Cooking, cleaning, walking
    NR
    NR
    PM2.5 and PMi0; indoor and outdoor; tapered element oscillating microbalance (TEOM) instruments. 2 days were monitored for
     PM25, and2forPM10.
    NR
    NR
    Evaporative coolers were found to act as PM filters, creating indoor concentrations approximately 40% of outdoor PMio and
     35% of outdoor PM2.5, regardless of cooler type.
    Liu et al. (2003, 073841)
              Study Design
                    Period
                  Location
                Population
               Age Groups
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
           Primary Findings
    Comprehensive exposure assessment
    1999-2001
    Seattle, WA
    High-risk sub populations
    Children 6-13 yr, elderly 65-90 yr (one person was below 65, but his/her age was not specified)
    Harvard Personal Environmental Monitor for PM2 5 (HPEM2 5)
    PM25,PM10
    PM25,PM10
    PM2.5, PM10
    Average personal PM2.5 exposure was similar to ambient PM2.5 concentrations but much higher than average indoor
     concentrations.  Personal, indoor, and outdoor PM2.5 and PM10, as well as the ratio PM2.5/PM10, were all significantly higher
     during the winter. Personal PM2.5 and PM^ exposures were highest for the children in the study.
    Lung et al. (2007,156719)
                    Period
                  Location
    
               Age Groups
              Indoor Source
    
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Weekdays between Nov 1998 and Feb 1999
    6 communities in Taiwan, China 2 in Taipei, 2 in Taichung, and 2 in Kaohsiung. Sites are industrial, commercial, residential and
     mixed.
    18to>70
    Being in kitchen, park, major boulevard, stadium, incense burning, household work, factory, environmental tobacco smoke,
     traffic, ventilation conditions
    Personal Environmental Monitor with a SKC personal pump at 2 L/min, 37 mm Teflon filters
    PM10
    PM10
    PM10
    None
    Outdoor rather than indoor levels contributed significantly to personal exposure. Important factors include time spend outdoors
     and on transportation, riding a motorcycle, passing by factories, cooking or being in the kitchen, incense burning at home.
    Meng et al..  (2005, 081194)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
    
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Evaluation of the use of central-site PM, rather than actual exposure, in PM epidemiology
    Summer 1999-spring 2001
    3 cities:Houston (TX), Los Angeles County (CA), and Elizabeth (NJ)
    NR
    NR
    NR
    MSP monitors on the front strap of the sampling bag near the breathing zone. Pump, battery, and motion sensor were on the
     hip or back.
    PM2.5
    PM2.5
    PM2.5
    EC,OC,S,Si
    Use of central-site PM2 5 as an exposure surrogate underestimates the bandwidth of the distribution of exposures to PM of
     ambient origin.
    December 2009
                                           A-305
    

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    Meng et al. (2005, 058595)
              Study Design
                    Period
                  Location
                Population
             Indoor Source
           Personal Method
             Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    RIOPA study matched indoor home & outdoor exposure assessment
    May-October (hot); November-April (cool); (1999-2001)
    Los Angeles County, CA; Elizabeth, NJ; Houston, TX
    Non-smoking homes
    Combustion (primary); atmospheric (secondary); sulfate, organics, nitrates; mechanically (abrasion) generated.
    Filter (not specified)
    NR
    Indoor home.; PM2.5
    PM2.5, outdoor home
    Organic and elemental carbon; 24 elements (metals).
    The median contribution of ambient sources to indoor PM2.5 using the mass balance approach was 56% for all study homes,
     63% for California, 52% for New Jersey, and 33% for Texas.
    Molnar et al. (2005,156772)
              Study Design
                    Period
                  Location
                Population
               Age Groups
             Indoor Source
           Personal Method
             Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Indoor/outdoor exposure assessment related to domestic wood burning
    10 February to 12 March 2003
    Hagfors, Sweden
    Adult residents of Hagfors
    NR
    NR
    Integrated filter samples with a dichotomous virtual impactor to separate PM10.25 from PM25
    PM2.5
    PMio-2.s, PM2.5
    PM10-25, PM25
    BS, S, Cl, K, Ca, Mn, Fe, Cu, In, Br, Rb, Pb
    Wood burning made statistically significant contributions to personal exposure to K, Ca, and Zn.  Cl, Mn, Cu, Rb, Pb, and BS
     were found to be potential personal exposures from wood smoke, but their association was not always statistically significant.
     S had no significant association with personal exposure to wood smoke.
    Molnar et al. (2006,156773)
              Study Design
                    Period
                  Location
                Population
               Age Groups
             Indoor Source
           Personal Method
             Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Cross-sectional
    Autumn and spring in 2002 and 2003
    Goteborg, Sweden,
    Persons living in urban settings
    20 subjects 20-50 yr randomly selected from the population and 10 from departmental colleagues.
    NR
    Integrated filter samples with cyclones for PM25 and PM, cut points
    PM25andPM1
    NR
    NR
    S, Cl, K, Ca, Ti, V, Mn, Fe, Ni, Cu, Zn, Br, Pb
    Personal exposure to Cl, K, Ca, Ti, Fe, and Cu in PM2.5 were significantly higher than outdoor and central site ambient
     concentrations, and personal exposure to Cl, Ca, Ti, Fe, and Br were also significantly higher than indoor levels. In most
     cases, indoor concentrations were not higher than  outdoor concentrations.
    Na and Cocker (2005,156790)
              Study Design
                    Period
                  Location
                Population
               Age Groups
             Indoor Source
    
           Personal Method
             Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    Human exposure assessment
    Sept. 2001-January 2002
    Mira Loma, CA
    Residential homes  and a high school
    NR
    Indoor EC (elemental carbon) concentrations primarily of outside origin; Indoor PM2 5 significantly influenced by indoor OC
     (organic carbon) sources, including indoor smoking.
    Integrated filter samples for PM25
    PM2.5
    NR
    PM2.5
    EC.OC
    Indoor PM25 was significant influenced by indoor OC sources. Indoor EC sources were predominantly of outdoor origin.
    December 2009
                                           A-306
    

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    Naumova et al. (2003, 089213)
              Study Design
    
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
    RIOPAStudy-PAH partitioning indoor and outdoor pollutants to evaluate the hypothesis that outdoor air pollution contributed
     strongly to indoor air pollution.
    July 1999-June 2000
    Los Angeles, CA, Houston, TX, Elizabeth, NJ
    Houses
    NR
    NR
    Modified MSP Samplers, 37 mm quartz filter
    PM2.5
    PM2.5
    PM2.5
    OC, EC
    Both EC and OC were associated with gas/particle partitioning of PAHs, with EC being a better predictor. High correlation
     between EC and OC suggests that PAHs adsorb onto PM containing EC during combustion.
    Nerriere et al.  (2005, 0894811
              Study Design
    
                    Period
                  Location
                Population
    
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Copollutant(s)
           Primary Findings
    Exposure assessment with stratified sampling of children and adults in 3 environments: high traffic emissions, local industrial
     sources, and urban background.
    "Hot" season May-June and "cold" season Feb-Mar. Grenoble in 2001, Paris in 2002, Rouen in 2002-2003, Strasbourg 2003.
    Grenoble, Paris, Rouen, and Strasbourg, France
    Persons living, working, or going to school in 3 urban areas one highly exposed to traffic emissions, one influenced by local
     industrial sources, and a background urban environment. Industrial sources of pollution were present in each city.
    6-13 yr and 20-71 yr. All non-smokers and not exposed to environmental tobacco smoke or industrial air pollution.
    NR
    Rucksack with Harvard ChemPass
    PM25,PM10
    NR
    PM25,PM10
    N02
    The difference between ambient air concentrations and average total exposure is pollutant specific. PM2.5 and PM10
     concentrations underestimate population exposures across almost all cities, season, and age groups, but the opposite is true
     for N02.
    Noullett et al  (2006,155999)
    
              Study Design   Cohort
                    Period   5 February to 16 March 2001
                  Location   Prince George, British Columbia
                 Population   Children
               Age Groups   10-12 yr
              Indoor Source   NR
           Personal Method   PM2.5 Harvard Personal Environment Monitors (HPEM2.5)
              Personal Size   PM2.5
      Microenvironment Size   NR
              Ambient Size   PM2.5
             Component(s)   S042", ABS (light absorbing carbon)
           Primary Findings   Thermal inversions were associated with personal exposures as well as ambient PM2 5 concentrations and likely caused
                            observed spatial variability. However, ambient sampling locations were correlated in time. Similar observations were made for
                            S042' and ABS.
    December 2009
                                            A-307
    

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    Rojas-Bracho et al. (2004, 054772)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
    
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Cohort study with repeated measures.
    Winter or summer of 1996-1997
    Boston, Massachusetts
    COPD patients
    Adult
    Housecleaning, cooking, transport in motor vehicles, low-effort home activities, moderate-effort home activities, activities in
     public places, and resting or sleeping.
    PEM
    PM2.5, PM10, and PM10.2.5
    PM25, PMlo, & PM10-25
    NR
    NR
    During both seasons, personal exposures were higher than indoor or outdoor means, except during the winter when indoor
     concentrations were  higher than the personal or outdoor.
    Rotko et al. (2002, 037240)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Copollutant(s)
           Primary Findings
    European multi-city air pollution study
    Athens, Greece:26 January 1997-4 June 1998
    Basel, Switzerland 3 February 1997-23 January 1998
    Milan, Italy 10 March 1997-23 May 1998
    Oxford, UK November 1998-7 October 1999
    Prague, Czech Republic 3 June 1997-4 June 1998
    Helsinki, Finland 26 September 1996-10 December 1997
    Athens, Greece; Basel, Switzerland; Milan, Italy; Oxford, UK; Prague, Czech Republic; Helsinki, Finland
    Adults
    25-55 yr
    NR
    Integrated 48-h PM2 5 filter samples
    PM2.5
    PM2.5
    PM2.5
    N02
    Personal PM2.5 and N02 levels were associated with subjects' level of annoyance. Highest annoyance levels occurred while in
    traffic.
    Sanderson and Farant (2004,156942)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Indoor and outdoor air monitoring of PAH. Investigate the relationship between indoor and outdoor PAH.
    NR
    Canada
    Residential homes in neighborhoods around aluminum smelting plant
    NR
    NR
    Indoor quartz filter sample
    PM2.5
    NR
    NR
    4-6 ring PAHs on indoor particle
    Indoor concentration of 4-6-ring PAH were linked to outdoor industrial sources in residences without any major indoor source,
     but with industrial facility as the main outdoor source. This study suggests that simultaneous measurements of indoor and
     outdoor concentrations of PAH >4 rings predominantly associated with fine PM could provide useful estimates of particle
     infiltration efficiency.
    December 2009
                                            A-308
    

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    Sarnat et al. (2006, 089166)
              Study Design
                    Period
                  Location
                Population
             Indoor Source
    
           Personal Method
             Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
                           Outdoor-indoor pollutant infiltration, occupied residences
                           July28,2001-February25,2002
                           Los Angeles, CA
                           NR
                           Yes; cleaning, cooking, home ventilation (open windows/doors), kitchen fans, air conditioner/heating usage, number of
                            occupants, nearby roadways
                           NR
                           NR
                           PM2.5, Particle number
                           PM2.5
                           BC (nonvolatile component) ; N03 (volatile component)
                           Infiltration rate for PM2.5 was intermediate, while BC was highest and N03 lowest. Infiltration rate varied with particle size, air
                            exchange rate, outdoor N03. PM2.5 infiltration was lowest for volatile components. Outdoor volatile PM25 components may be
                            less representative of indoor exposure to volatile PM25 of ambient origin. Outdoor nonvolatile PM25 components may be more
                            representative of indoor exposure to nonvolatile PM25 of ambient origin.
    Sarnat et al. (2006, 090489)
    
              Study Design   Personal and ambient exposure assessment
                    Period   June 14-August 18 (summer); Sep 24-Dec 15 (fall), 2000
                   Location   Steubenville, OH
                 Population   Non-smoking, older adults
               Age Groups   NR
           Personal Method   Integrated filter gravimetric measurement
              Personal Size   PM2.5
      Microenvironment Size   NR
              Ambient Size   PM2.5
             Component(s)   S042"; EC
           Primary Findings   24-h ambient measurements are more representative of personal particle exposure than gases, and ventilation is an important
                            exposure modifier.
    
    
    
    Sarnat et al. (2005. 087531)
    
              Study Design   Time-series epidemiologic study
                    Period   Summer 1999 and winter 2000
                   Location   Boston, MA. Comparisons to a previous study in Baltimore are also made.
                 Population   School children and seniors
               Age Groups   NR
              Indoor Source   PM2.5
           Personal Method   NR
              Personal Size   PM2.5
      Microenvironment Size   NR
              Ambient Size   PM2.5
             Component(s)   S04,
              Copollutant(s)   03, N02, S02
           Primary Findings   Substantial correlations between ambient PM25 concentrations and corresponding personal exposures. Summertime gaseous
                            pollutant concentrations may be better surrogates of personal PM25 exposures (especially personal exposures to PM25 of
                            ambient origin) than they are surrogates of personal exposures to the gases themselves.
    
    
    
    Shalatetal. (2007. 156971)
    
              Study Design   Indoor home exposure assessment; sampling technology demonstration
                    Period   Winter heating season
                   Location   Residential home
                 Population   Children
               Age Groups   Pre-toddler (6- to 1 2-month-old) children
              Indoor Source   NR
           Personal Method   Integrated filter and real-time  nephelometer at floor height and at a height of 11 0 cm
              Personal Size   TSP, inhalable PM
      Microenvironment Size   NR
              Ambient Size   NR
              Copollutant(s)   NR
           Primary Findings   The study results suggest that young children are exposed to more inhalable PM and TSP because PM becomes resuspended
                            from the floor with motion.
    December 2009
                                                                   A-309
    

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    Shao et al. (2007,156973)
    
              Study Design   Exposure assessment
                    Period   July and Winter 2003
                  Location   Beijing, China
                 Population   General population
               Age Groups   NR
             Indoor Source   NR
           Personal Method   PMio measured with integrated filter samples
             Personal Size   PMio
      Microenvironment Size   PMio
              Ambient Size   PM10
             Component(s)   NR
           Primary Findings   Plasmid scission assay, coupled with the image analysis, can be used to evaluate the relationship between particle physico-
                            chemistry and toxicity.
    
    
    
    Shilton et al. (2002. 049602)
    
              Study Design   Respirable particulates inside and outside of a building were collected and compared
                    Period   24-h sampling from 12:45 pm Mondays to Fridays between 9/19/00 to 5/01/01
                  Location   Wolverhampton city center, University of Wolverhampton, UK
                 Population   NR
             Indoor Source   Mn,AI, N03, CI" (wind-blown dust), Cu and Zn"
           Personal Method   Active sampling using Casella sampler (filter)-
             Personal Size   Respirable PM
      Microenvironment Size   Respirable PM
              Ambient Size   Respirable PM
             Component(s)   N03", metals (Zn, Cu, Mn, Al), S042", CI"
           Primary Findings   The indoor particulate concentration was driven by ambient concentration, and meteorological-induced changes in ambient PM
                            were detected indoors.
    Strand et al. (2007,157018)
              Study Design
                    Period
                  Location
                 Population
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Cohort
    Winter of 1999-2000 and winter of 2000-2001
    Denver, Colorado
    Asthmatic children
    NR
    Modeling/extrapolation from fixed-site ambient monitoring (multiple methods)
    NR
    NR
    PM2.5
    NR
    Using modeled or extrapolated personal ambient PM exposure results in a deattenuation of decrements in FEV, associated with
     PM exposure, relative to use of fixed-site ambient monitoring PM levels. Associations between FEV1 decrements and the
     various estimation procedures (modeling and extrapolation) were similar to each other.
    Tang et al. (2007, 091269)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Cohort Study
    12/2003-2/2005
    Sin-Chung City, Taiwan
    Asthmatic children
    6-12 yr
    No
    Portable particle monitor; DUSTcheck Portable Dust Monitor, model 1.108, GRIMM Labortechnik Ltd., Germany
    PM10,PM25, PM^PM^s, PM25-i
    NR
    PM10,PM25, PMio-25-
    NR
    Results of linear mixed-effect model analysis suggested that personal PM data was more suitable for the assessment of change
     in children's PEFRthan ambient monitoring data.
    December 2009
                                           A-310
    

    -------
    Thornburg et al. (2004,157052)
    
              Study Design  PM exposure studies
                    Period  RTP: Summer 2000-spring 2001
                           Tampa: October-November 2002
                  Location  Research Triangle Park (RTP), NC and Tampa, FL
                Population  Residential home occupants
               Age Groups  NR
              Indoor Source  Resuspension of PM10 from a carpet and cooking
           Personal Method  Harvard impactors and PEMs, ME pdMOOO nepholometer
              Personal Size  PM2.5, PM10
      Microenvironment Size  NR
              Ambient Size  PM2.5, PM10
              Component(s)  NR
           Primary Findings  The association of duty cycle with indoor-outdoor (I/O) ratio was confounded by the short time span of ventilation system
                            operation and the presence of strong indoor sources.
    Toivola et al. (2002, 0265711
              Study Design  Random sample of teachers
                    Period  Nov 1998-Mar 1999 and Nov-Dec 1999
                  Location  2 cities in eastern Finland
               Age Groups  Adult
              Indoor Source  Fungi, bacteria
                Population  Elementary school teachers
           Personal Method  Button inhalable aerosol sampler
              Personal Size  Particle  Mass; BS
      Microenvironment Size  Particle  Mass; BS
              Ambient Size  NR
              Component(s)  Total fungi, total bacteria, viable fungi, viable bacteria
           Primary Findings  Personal BS exposure correlated with both home and work BS exposures. BS concentrations explained best the variation of
                            particle mass in personal and home concentrations.
    Trenga et al. (2006,155209)
              Study Design
                    Period
                  Location
                Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Panel study with repeated measures
    3 sampling periods Oct 1999-Aug 2000, Oct 2000-May 2001, Oct 2001-Feb 2002
    Seattle, Washington
    Adults with and without COPD and children with asthma
    adults ages 56-89 and children ages 6-13
    NR
    Carrying personal monitor (Harvard Personal Environmental Monitor for PM25)
    PM2.5
    PM2.5
    PM10-2s, PM25for residential outdoor, PM25 for central site
    NR
    FEVi decrements associated with 1 -day lagged central site PM2.5 in adult subjects with COPD. Associations between PM and
     lung function decrements were significant only in asthmatic children not receiving anti-inflammatory medication.
    Turpin et al. (2007,157062)
              Study Design
                    Period
                  Location
                Population
              Indoor Source
           Personal Method
    
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    RIOPAStudy 24-h integrated indoor, outdoor, and personal samples collected in 3 cites.
    Summer 1991-spring 2001
    Elizabeth, NJ, Houston, TX, and Los Angeles County, CA
    309 adults and 118 children (89-18)
    NR
    PEM on the front strap of a harness near the breathing zone. The bag on the hip contained the pump, battery pack, and motion
     sensor
    PM2.5
    PM2.5, in the main living area (not kitchen)
    PM2.5, in the front or backyard
    18 volatile organics, 17 carbonyl, PM2.5 mass and >23 PM2.5 species, organic carbon, elemental carbon, and PAHs
    The best estimate of the mean contribution of outdoor to indoor PM2 5 was 73% and the outdoor contribution to personal was
     26%.
    December 2009
                                           A-311
    

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    Vallejo et al. (2006,157081)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Panel study
    4/2002-8/2002
    Mexico City, Mexico
    Health young, non-smoking adults
    Mean age 27 yr
    NR
    pDR nephelometric method
    PM2.5
    NR
    NR
    NR
    The descriptive analysis showed that overall outdoor median concentration of PM2.5 was higher than the indoor concentration.
     In the indoor microenvironment, the highest concentrations occurred in the subway followed by the school, and the lowest was
     at home. The outdoor microenvironment with the highest concentrations was the public transportation (bus), while the
     automobile had the lowest. It was found that PM2.5 concentration levels had a circadian-like behavior probably related to an
     increase in the population daily activities during the morning hours, which decrease in the evening, especially at indoor
     microenvironments. The Center city area was found to have the highest concentrations of PM2.5.; Multivariate analysis
     corroborated that PM25 concentrations are mainly determined by geographical locations and hour of the day, but not by the
     type of microenvironment.
    van Roosbroeck et al. (2006, 090773)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Personal exposure assessment, effect of traffic-related pollutants
    March-June 2003
    Amsterdam, The Netherlands
    Schoolchildren
    9-12 yr
    ETS, cooking
    Integrated filter gravimetric measurement. Light absorbance.
    PM2.5
    NR
    PM2.5
    Absorbance
    Children living near busy roads had 35% higher personal exposure to 'soot' than children living in urban background locations.
    Vinzents et al. (2005, 087482)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
           Primary Findings
    Panel study
    3/2003-6/2003
    Copenhagen, Denmark
    Healthy young adults
    Mean age = 25 yr
    No
    Condensation  particle counters
    UFP(10-100nm)
    UFP(10-100nm)
    PM10
    UFP exposure predicted oxidative DNA damage.
    Wallace and Williams (2005, 057485)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Cohort
    2000-2001
    Raleigh, North Carolina
    African-American persons with elevated risk from exposure to particles.
    NR
    NR
    PEM PM2 5 monitor
    PM2.5
    Indoors PM2.5
    Outdoors near residence PM25 PM25
    S
    Using outdoor particles to determine the effect on health is not accurate. The infiltration factor is a good estimator for personal
     exposure. Indoor and outdoor measurements of sulfur could be used in the absence of personal exposure measurement to
     estimate the contribution of outdoor fine particles to personal exposures.
    December 2009
                                            A-312
    

    -------
    Wallace et al. (2006, 088211)
              Study Design
    
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Time series continuous monitoring of subjects with controlled hypertension or implanted defibrillators were monitored for 7
     consecutive days in 4 seasons.
    2000-2001
    North Carolina
    Health-compromised adults, non-smokers
    Adults
    Cooking, cleaning, personal care, smoking
    PEM
    PM2.5
    PM2 5; Indoor and outdoor
    NR
    NR
    Use of continuous particle measuring instruments allowed more precise identification of sources, frequency and magnitude of
     short-term peaks, and more accurate calculation of individual personal clouds.
    Wang et al. (2006,157108)
              Study Design
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Exposure assessment, identification of sources of outdoor and indoor PM and trace elements
    Aug4-Sep10,2004
    Guangzhou, China
    4 hospitals
    NR
    NR
    No personal exposure assessment was conducted.
    NR
    PM10,PM25
    PM10,PM25
    Na, Al, Ca, Fe, Mg, Mn, Ti, K, V, Cr, Ni, Cu, Zn, Cd, Sn, Pb, As, Se
    High correlation between PM2.5 and PMio suggest that they came from similar emission sources. Outdoor infiltration could lead
    to direct transportation of PM indoors. Human activities and ventilation types could also influence indoor PM. levels.
    Ward et al. (2007,157112)
              Study Design
                    Period
                   Location
                 Population
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Indoor air sampling to determine size fractionated concentrations of PM, OC, EC, and total carbon
    Jan-Mar 2005
    Libby, Montana
    Children exposed to wood-burning stoves in elementary and middle schools
    Burning wood in stoves for heating
    NR
    NR
    PM >2.5,1.0-2.5, 0.5-1.0, 0.25-0.5, and < 0.25 urn
    PM >2.5,1.0-2.5, 0.5-1.0, 0.25-0.5, and < 0.25 urn
    OC and EC
    Total measured PM mass concentrations were much higher inside the elementary schools, with particle size fraction (>2.5, 0.5-
     1.0, 0.25-0.5, and < 0.25 mm) concentrations between 2 and 5 times higher when compared to the middle school. The 1.0-2.5
     mm fraction had the largest difference between the two sites, with elementary school concentrations nearly 10 times higher
     than the; middle school values.
    Weisel et al. (2005,1571311
              Study Design
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
    
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Matched indoor, outdoor, and personal concentrations in proximity to pollution sources.
    May 1999-Feb 2001
    Elizabeth, NJ, Houston, TX, and Los Angeles County, CA
    urban children and adults
    Children and adults (6-89 yr)
    Age of house, recent renovations (< 1 yr), type of home (single, multiple family), attached garage, carpet indoors, local pollution
     sources.
    PEM on a harness with inlet near breathing zone.
    PM2.5
    PM2.5
    PM2.5
    NR
    Personal PM2.5 was significantly higher than indoor and outdoor PM2.5 concentrations.
    December 2009
                                            A-313
    

    -------
    Wichmann et al. (2005, 086240)
            Study Design
                  Period
                Location
              Population
             Age Groups
           Indoor Source
         Personal Method
           Personal Size
    Microenvironment Size
            Ambient Size
           Component(s)
         Primary Findings
                           Exposure assessment
                           November 29, 1993-March 30, 1994; October 17, 1994-December 22, 1994
                           Amsterdam, The Netherlands
                           Adults and schoolchildren living near high-traffic or low-traffic roads
                           Adults (50-70 yr), schoolchildren (10-1 2 yr)
                           NR
                           Personal impactor
                            PM10
                            Absorbance coefficient measurements
                            Found tentative support for using type of road as a proxy for indoor and personal exposure to traffic-related absorbance PM.
    Williams et al. (2003. 053338)
    
              Study Design  Cohort study, longitudinal
                    Period  Summer 2000, fall 2000, winter 2001 , and spring 2001
                  Location  Raleigh and Chapel Hill, North Carolina
                 Population  Elderly persons
               Age Groups  > 50 yr
              Indoor Source  Occasional ETS
           Personal Method  Integrated filter samples
              Personal Size  PM2.5
      Microenvironment Size  PM2.5; PMi0; PM^-is
              Ambient Size  PM2.5; PM10; PM10-2.5
              Component(s)  NR
           Primary Findings  When comparing cohorts, there was no statistically significant difference between PM2.5 exposure. Little spatial variability was
                            observed regarding PM2.5 concentrations; this was observed to a lesser extent for PM^ as well.
    Wilson and Brauer (2006, 088933)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
                         Exposure assessment
                         April-September 1998
                         Vancouver, Canada
                         Subjects with physician-diagnosed COPD
                         54-86-years-old
                         No
                         Personal integrated filter gravimetric measurement; TEOM outdoor ambient
                         PM2.5
                         NR
                         NR
                         S042'
                         It was observed that ambient PM2.5 exposure, estimated with the S042" method, accounted for 71 % of measured ambient
                          concentration and 44% of measured total personal exposure. No correlation between nonambient exposure and ambient
                          concentration was observed.
    Wu et al.  (2006,179950)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
                         Panel study
                         9/3/2002-11/1/2002
                         Pullman, WA
                         Asthmatic adults
                         18-52yr
                         No
                         Co-located Harvard Personal Environmental Monitors (HPEM2.5; Harvard School of Public Health, Boston, MA)\
                         PM2.5
                         PM2.5
                         PM2.5
                         Levoglucosan (LG); Elemental Carbon (EC); Organic Carbon (OC)
                         The authors observed significant variability between subjects for burning and nonburning episodes. The authors postulated that
                          activity patterns contribute to this variability and that central-site measurements of LG might not be a good surrogate for
                          biomass combustion smoke exposureforthis reason.
    December 2009
                                                                A-314
    

    -------
    Wu et al.  (2005, 086397)
    
              Study Design   Panel study
                    Period   1999-2000
                  Location   Alpine, CA
                 Population   Asthmatic children
               Age Groups   9-17 yr
                            NR
                            pDR
                            PM2.5
                            PM2.5
                            PM2.5
                            NR
           Primary Findings   Personal exposure was higher than those affixed sites. Subjects received only 45.0% of their exposure indoors at, although
                            they spent more than 60% of their time there. In contrast, 29.2% of their exposure was received at school where they spent
                            only 16.4% of their time. Thus, exposures in microenvironments with high PM levels where less time is spent can make
                            significant contributions to the total exposure.
           Indoor Source
         Personal Method
           Personal Size
    Microenvironment Size
            Ambient Size
           Component(s)
    Yeh and Small (2002, 040077)
              Study Design
                    Period
                  Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
                         Comparative assessment of AME and IES models
                         1997 (364 days) spring March-May, summer June-August, Fall September-November, winter December-February
                         Los Angeles County, CA
                         General population; ETS and non-ETS Homes
                         NR
                         Indoor Cooking, ETS, Other sources and unexplained particulates that maybe generated with engaging in various activities
                         NR
                         PM10PM25
                         NR
                         PM10PM25
                         NR
                         Adjusting from outdoor concentrations to personal exposures and correcting dose-response bias produce nearly equal results.
                          Roughly the same premature mortalities associated with short-term exposure to both ambient PM2.5 and PM10 are predicted by
                          both models
    Yip et al. (2004,157166)
              Study Design
    
                    Period
                  Location
                 Population
               Age Groups
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
             Component(s)
           Primary Findings
                         A panel study with repeated measures with personal & home monitoring for 8 2-week Periods. Children were stratified into
                          smoking and non-smoking households.
                         2000-2001
                         Detroit, Michigan
                         School-age children with asthma
                         7-11 yr
                         PEM in a backpack
                         PM10
                         PMi0; indoor  at home & indoor at school
                         PM10
                         NR
                         Personal PM concentrations were significantly correlated with home environment (r = 0.38 to 0.70), with the strongest
                          relationships in home with non-smokers.
    December 2009
                                                                A-315
    

    -------
    Zhao et al. (2006,156181)
              Study Design
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
    
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Aerosol source apportionment under four environments (personal, residential indoor, residential outdoor and ambient) to
     evaluate the relationship between different environments through exposure analysis, and to demonstrate the utility of the
     combined receptor model on air quality studies of various environments.
    June 2000 to May 2001
    Raleigh and Chapel Hill, NC
    NR. People with respiratory ailments most likely.
    NR
    4 main sources to residential indoor PM Cu-factor mixed with indoor soil, secondary sulfate, Personal care and activity, ETS and
     its mixture
    PEMandHI
    NR
    NR
    NR
    S042", OC, EC, and trace elements
    Secondary S042" and vehicle emissions were significant contributors of personal PM exposure and residential indoor PM
     concentrations.
    Zhao et al. (2007,156182)
              Study Design
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Ambient Size
              Component(s)
           Primary Findings
    Comprehensive analysis of the sources of PMi5 exposure on children with moderate to severe asthma in urban-poor settings.
    Two winter periods (October 2002-March 2003 and October 2003-March 2004)
    Elementary school for children with significant asthma, Denver, CO
    Schoolchildren in urban-poor settings suffering from moderate to severe asthma
    6-13 yr (60% in the range 10-13 yr, rest in the range 6-9 yr)
    Yes, House cleaning compounds, and smoking were identified as primary internal sources.
    PEM
    PM2.5
    PM2.5
    PM2.5
    EC.CI.Si, N03
    Four external sources and three internal sources were resolved in this study. Secondary nitrate and motor vehicle were two
     major outdoor PM2.5 sources. Cooking was the largest contributor to the personal and indoor samples. Indoor environmental
     tobacco smoking also has an important impact on the composition of the personal exposure samples.
    Zhu et al.  (2005,157191)
              Study Design
    
                    Period
                   Location
                 Population
               Age Groups
              Indoor Source
           Personal Method
              Personal Size
      Microenvironment Size
              Component(s)
           Primary Findings
    4 apartments near the freeway were monitored at 2 times for 6 consecutive days, 24 h per day. Subjects did not enter the
     bedrooms where the samplers were, no cooking, cleaning, children, or pets.
    Oct. 2003-Dec. 2003 and Dec. 2003-Jan. 2004
    Los Angles, CA
    Urban Populations near major freeways.
    NR
    NR
    NR
    Indoor and Outdoor ultrafine particles (6-220 nm)
    NR
    CO
    The size distributions of indoor aerosols showed less variability than the adjacent outdoor aerosols. Indoor to outdoor ratios for
     ultrafine particle concentrations depended strongly on particle size. I/O ratios were dependent on the indoor ventilation
     mechanisms applied. Size-dependent particle penetration factors and deposition rates were predicted from data by fitting a
     dynamic mass balance model.
    December 2009
                                            A-316
    

    -------
    Zollner et al. (2007,157192)
              Study Design
                    Period
                  Location
                Population
               Age Groups
           Personal Method
              Personal Size
      Microenvironment Size
    
              Ambient Size
    
           Primary Findings
            Exposure assessment
            Winter Period of 2005 and 2006
            Baden-Wuerttemberg, Germany
            School children
            NR
            NR
            NR
            They only reported concentrations for PM2.5. PM ranging in size from 0.02 to >20 |im were collected and analyzed but only
             PM2.s concentration were reported.
            They only reported concentrations for PM2.5. PM ranging in size from 0.02 to >20 |im were collected and analyzed but only
             PM2.s concentration were reported.
            The impaction of PM was strongly influenced by specific weather conditions. Time resolution of measurements in classrooms
             showed variation in particle concentration depending on the type of building and indoor activities. E'[Concentrations of very
             small particles indoors and in ambient air measured by condensation particle counter were influenced by traffic emissions.
    Table A-59.    Examples of studies showing developments with UFP sampling  methods since the 2004
                      PMAQCD.
    Reference
    Biswas et al.
    (2005, 150694)
    Feldpausch et
    al. (2006,
    155773)
    Heringetal.
    (2005, 155838)
    Hermann etal.
    (2007, 155840)
    Kinsey et al.
    (2006, 130654)
    Kulmala et al.
    (2007, 097838)
    Kulmala et al.
    (2007, 155911)
    PM Size PM
    Ranges Constituents
    
    20-100 Carbonaceous
    nm aerosols
    
    3-40 nm Ag, NaCI
    10nm-5 nF
    urn
    
    i in n™ Atmospheric
    2-20nm aerosol, Ag
    Instruments
    CPC (water)
    DS with CPC, compared with
    DMA
    CPC (water)
    CPC (water and butanol)
    TEOM, SMPS, CPC, DustTrak, E-
    BAM.ELPI, integrated filter
    samples
    CPC
    Battery of CPCs (water, butanol,
    n-butanol)
    Study Description
    Water-based CPC performance evaluation.
    The DS with CPC compared fairly well with the DMA for particle sizes
    up to 40 nm with 20-40% underestimation depending on discharge
    frequency settings. The DS sampling period is 3-5 s in comparison with
    the 1 min scanning time of the DMA.
    Water-based CPC performance evaluation.
    Roughly 95% collection efficiency for d >5 nm for TSI models 3776 and
    3786, 95% efficiency for d >20 nm for model 3775, near 90% efficiency
    for d>20 nm for model 3785, near 90% efficiency for d >25 nm for
    model 3772.
    TEOM compared best with gravimetric filter among mass concentration
    analyzers, ELPI and SMPS comparable for differential number
    distribution but ELPI not useful for gravimetric analysis because mass is
    not significant at small end of distribution.
    Changing temperature difference between saturator and condenser
    within CPC allowed for differences in cut-off diameters.
    Used the battery to discriminate between water-soluble, water-insoluble,
    butanol-soluble, and butanol-insoluble nucleation-mode particles.
    Ntziachristos
    and Samaras
    (2006,116722)
    7 nm-1
    urn
    Automobile
    exhaust
    5 instruments used
    simultaneously to reduce
    uncertainty: Teflon-coated filter
    downstream of constant volume
    sampling, ELPI with
    thermodenuder, CPC, SMPS,
    diffusion charger
    Use of four reduced variables combining output from all instruments
    (ratio of particle number concentration from CPC and ELPI, estimated
    mean geometric mobility diameter from signal of diffusion charger and
    number concentration from CPC, ratio of signal of diffusion charger to
    constant volume sampler mass, ratio of constant volume sampler mass
    to volume collected by ELPI) resulted in  identification of clear outliers
    and factors related to driving and fuel properties rather than
    measurement errors.
    Olfert et al.
    (2008,156004)
                   30-100
              NaCI, ambient   FIMS (compared with SMPS)
                                                 Particle number concentrations reported by the FIMS were 8-23%
                                                 higher than the SMPS using an inversion technique designed to correct
                                                 for particle residence time in the FIMS, which operates at 0.1 s
                                                 resolution.
    Petaja et al.
    (2006,156021)
                             CPC (water)
                                                 Water-based CPC performance evaluation.
    Winkleretal.
    (2008,156160)
    1.5-4 nm   Tungsten oxide   CPC (n-Propanol)
                                                 Authors remove excess charge on particles with ion trap to detect
                                                 particles down to ~ 1 nm (by eliminating electrostatic attraction to
                                                 agglomerate).
    December 2009
                                                   A-317
    

    -------
    Table A-60.   Summary of in-vehicle studies of exposure assessment.
    Reference
    Briggs et al.
    (2008, 156294)
    Diapoulietal.
    (2007, 156397)
    Fruin et al. (2008,
    097183):
    Westerdahletal.
    (2005, 086502)
    [Note: same data
    presented.]
    Gomez-Perales et
    al. (2004,
    054418)
    Study Design Mode of Transport
    UFP (P-Trak), PM,o, PM25, and PM, Car
    (OSIRIS light scatter) were operated in a
    car while driving or walking on one of 48 Walking
    routes in London. Trips ranged 1.5-15 min
    by car and were repeated up to 5 times to
    improve statistics.
    Study Period: Weekdays in May and June
    2005.
    UFP (CPC) concentrations were Car
    measured at school, residential, and in-
    vehicle environments in Athens, Greece.
    Study Period: school hours, Nov
    2003-Feb 2004 and Oct-Dec 2004
    On-road zero emissions vehicle driven on Car
    33-mi arterial road and 75-mi freeway
    measured UFP (CPCs, SMPS, BAD), BC
    (aethalometer), NOX (chemiluminescence),
    PM-bound PAHs (UV-photoionization), and
    CO (Q-Trak). DVD analysis of traffic
    density and car speed.
    Study Period: Feb-Apr 2003 for 2- to 4-h
    periods.
    PM2.s (personal filter pump), CO (T15 Bus
    electrochemical cell), and benzene
    (canister) were measured on transit Minibus
    routes, and PM2 5 filters were analyzed .. ,
    for mass, OC/EC, S042", N03-, and trace lvlelro
    metals.
    Exposures
    Units: PMrPMmfug/m0),
    UFP (pern"3)
    Avg Car Exposure:
    PM105.87 (3.09)
    PM25 3.01 (1.10)
    PM,1.82(1.10)
    UFP 21639 (14379)
    Avg Walking Exposure:
    PM1027.56(13.16)
    PM25 6.59(3.12)
    PM,3.37 (3.40)
    UFP 30334 (17245)
    15-min median
    (1000p/cm3):
    School indoor 13.6
    School outdoor 16.6
    Residence indoor11.2
    Residenceoutdoor24.0
    In-vehicle 78.0
    Arterial range of
    medians:
    UFP (1000p/cm3) 13-43
    PM2.5(ug/m3)7.9-45
    BC(ug/m3) 0.74-3.3
    Freeway range of
    medians:
    UFP (1000p/cm3) 47-190
    PM25(ug/m3)25-110
    BC(ug/m3)2.4-13
    PM2.5(ug/m3):
    Bus 68
    Minibus71
    Metro 61
    Primary Findings
    I n-car concentrations of PM2 5, PMi, and UFP
    correlated well with walking concentrations (R = 0.806,
    0.800, 0.799 respectively). Avg walking concentrations
    were 1.4-4.7 times higher than average in-car
    concentrations. Cumulative walking exposures (not
    shown here) were 4.4-15.2 times higher than those in
    cars, likely resulting from longer transit times for
    walking.
    In-vehicle UFP concentrations were roughly 3.5-7
    times higher than school or residence
    concentrations. Indoor concentration diel patterns
    were also shown to follow outdoor levels, which
    suggests that indoor levels are of outdoor origin.
    Measurements of freeway UFP, BC, PM-bound PAH,
    and NOK concentrations were roughly one order of
    magnitude higher than ambient measurements.
    Multiple regression analysis suggests these
    concentrations were a function of truck density and
    total truck count. (Only PM measurements reported
    here).
    Generally, PM2.5 concentration was higher in the
    morning than evening rush hour, but variability was
    higher for minibuses than other modes of transport.
    Wind speed was found to be associated with PM2.5
    concentration on minibuses.
                 Study period: 3-h morning and evening
                 rush hour May-June 2002
    December 2009
    A-318
    

    -------
    Reference
    Gomez-Perales et
    al. (2007,138816)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Gulliver and
    Briggs (2004,
    053238)
    
    Gulliver and
    Briggs (2007,
    155814)
    
    Study Design Mode of Transport
    PM2.5 (personal filter pump), CO (T15 Bus
    electrochemical cell), and benzene
    (canister) were measured on transit Minibus
    routes, and PM2 5 filters were analyzed ., ,
    for mass, OC/EC, S042", N03-, and trace lvlelro
    metals.
    Study period: 3-h morning and evening
    rush hour Jan-March 2003
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    PMio, PM2.5, and PMi sampled (OSIRIS Car
    light-scatter devices) in a car while
    driving or walking on northern corridor of ™lk
    Northhampton UK.
    Study Period: 1-h interval of morning and
    evening rush hour during Winter
    1999-2000.
    TSP, PM10, PM2.5, and PM, sampled Car
    (OSIRIS light-scatter devices) in a car
    while driving or walking on one of 48 ™lk
    routes in London. Trips ranged 1 .5-15
    min by car and were repeated up to 4
    times to improve statistics.
    Exposures
    Units: PM2.5 mass
    (ug/m ), components (%
    of mass)
    Bus:
    PM25 20-58
    (NH4035-8
    (NH4)2S0410-18
    OC 17-39
    EC 8-20
    Crustal15-18
    Non-crustal 2-3
    Unknown 6-24
    Minibus:
    PM25 25-55
    (NH4034-13
    (NH4)2S047-22
    OC22-37
    EC 9-1 9
    Crustal12-13
    Non-crustal 3-3
    Unknown 4-26
    Metro:
    PM25 24-41
    (NH4035-8
    (NH4)2S0410-21
    OC 35-42
    EC 9-1 3
    Crustal10-16
    Non-crustal 2-4
    Unknown 5-20
    Walking concentrations,
    Units: ug/rn
    Walk, Car, Background
    PM,0 38.2,43.2, 26.6
    PM2515.1,15.5
    PM, 7.1, 7.0
    
    Mean concentrations,
    Units: ug/rn
    Walk, Car, Background
    TSP-PM10 19.1 (19.8)
    18.2(18.0)4.9(5.1)
    Primary Findings
    Buses and minibuses had similar concentration
    levels for PM2.5 mass, and metro exposures were
    lower. CO and benzene concentrations were higher
    on minibuses than buses. OC was the largest PM
    constituent for all modes of transport. Measured
    concentrations were higher in the morning than in
    the evening rush hour periods. Maximum historical
    wind speeds (1995-2003) appeared to be inversely
    associated with measured concentration.
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    In-car PM^ concentrations were elevated
    compared with walking and background. PM2.5 and
    PM, concentrations were comparable for walking
    and background. Periods of elevated PM25
    compared with PM10 generally corresponded to
    times when S042~ levels were also high.
    
    Walking exposures larger than car and
    background, and car exposures were generally
    larger than background except for PMi. Peak
    exposures during walking were significantly higher
    than peak in-car exposures.
                      Study Period: Jan-Mar 2005.
                  PM10-2522.1 (22.8)15.1
                  (14.2)10.0(9.0)
    
                  PM25 -1 10.9(10.4)8.3
                  (8.4)7.6(7.1)
    
                  PM, 4.8 (3.4)2.9 (2.6)4.2
                  (2.4)       	
    Rossneretal.      Measured PM25 exposure of 50 city bus   Bus
    (2008,156927)     drivers and 50 controls in Prague, Czech
                      Republic using personal  samplers (type
                      not specified) and VOCs using passive
                      samplers. PM2.5 filters analyzed for c-
                      PAHs. Focus of study is oxidative stress
                      biomarkers in drivers.
    
                      Study period: winter 2005, summer
                      2006, winter 2006.
                  Units: ng/m
    
                  Winter 2005: Bus Control
                  C-PAH7.1 (3.7)9.4 (5.5)
                  B[a]P1.3(0.7)1.8(1.0)
    
                  Smmer 2006: BusControl
                  C-PAH1.8 (0.5)2.0 (0.8)
                  B[a]P0.2 (0.1)0.3 (0.2)
    
                  Wnter 2006:  Bus Control
                  C-PAH5.4 (3.5)4.1 (1.7)
                  B[a]P1.0(0.5)0.8 (0.4)
    c-PAH and B[a]P exposure to bus drivers was
    significantly higher in Winter 2006, but control
    exposure was significantly higher in Winter 2005
    for c-PAH and B[a]P and in summer 2006 for c-
    PAH. No significant difference in VOC exposure
    between bus drivers and controls was observed.
    Oxidative stress markers were significantly higher
    in bus drivers than controls for all seasons.
    December 2009
    A-319
    

    -------
    Reference
    Sabinetal.(2005,
    088300)
    
    
    
    
    
    
    
    
    
    
    Study Design
    BC (aethalometer), particle-bound PAH
    (UV-photoionization), and NO (luminol
    reaction) were measured on 3 diesel
    school buses, 1 diesel school bus with a
    particle trap, and one compressed gas
    bus during before- and after-school
    commutes.
    Study Period: May-June 2002.
    
    
    
    
    
    
    
    Mode of Transport
    School bus (diesel, diesel
    with particle trap (TO),
    compressed gas (CNG))
    
    
    
    
    
    
    
    
    
    
    Exposures
    In-bus mean
    concentration
    Units: BC(ug/m3)
    PAH (ng/m5)
    Windows closed:
    Dp DflU
    bU rAH
    Ambient: 2.5,27
    CNG:2.3,57
    10:7.1,190
    Diesel:11,290
    Windows open:
    BC PAH
    Ambient: 1.9,26
    CNG:1.5,43
    10:2.3,42
    Diesel: 3.9,58
    Primary Findings
    Mean concentrations on diesel buses without
    newer emissions control technologies were 2-4.4
    times higher than background. On buses with
    particle traps, concentrations were 1.2-2.5 times
    higher than background, while concentrations on
    compressed gas-fueled school buses were actually
    lower than background.
    
    
    
    
    
    
    
    
    Table A-61.    Summary of personal PM exposure studies with no indoor source during 2002-2008.
            Reference / Location
                Personal
                  Micro
                 Ambient
    SOUTHWEST
    Delfino et al. (2004, 056897)
    Alpine, California
    Method: pDR, Units = |ig/m°
    Last 2-hPM2 5 34.4 (33.7)
    Diurnal PM2 5 55.7(31.6)
    Nocturnal PM25 22.3 (13.6)
    1-h max PM25151.0(120.3)
    4-hmaxPM2587.5(55.3)
    8-hmaxPM2567.6(39.0)
    24-hPM25 37.9 (19.9)
    Method: HI, Units =
    lndoor24-hPM1030.3(11.9)
    Indoor 24-hPM2 5 12.1 (5.4)
    Outdoor 24-hPM1025.9 (10.4)
    Outdoor 24-hPM2511.0(5.4)
    Method: TEOM, Units = |ig/m°
    Diurnal PM1035.1 (11.3)
    Nocturnal PM10 23.3 (8.4)
    1-h max PM10 54.4 (13.8)
    4-h max PM10 44.5 (12.4)
    8-hmaxPM1039.8(11.2)
    24-hPM10 23.6 (9.1)
    24-h PM25 10.3 (5.6)
    Delfino et al. (2006, 090745)
    Riverside and Whittier, California
    Method: PEM, Units = ng/nf
    Riverside:
    n13
    24-hPM2532.78(21.84)
    1-h max PM25 97.94 (70.29)
    8-h max PM2.5 47.21 (30.0)
    
    Whittier:
    n32
    24-hPM2536.2(21.84)
    1-hmaxPM2593.63(75.19)
    8-h max PMis 51.75 (36.88)
                                      Method:FRM, Units = |ig/m°
                                      Riverside:
                                      24-hPM25 36.63 (23.46)
                                      24-h PM10 70.82 (29.36)
    
                                      Whittier:
                                      24-h PM25 18.0 (12.14)
                                      24-h PM10 35.73 (16.6)
    Turpin et al. (2007,157062)
    Los Angeles County, CA (and Elizabeth,
    NJ, Houston, TX)
    Method: PEM, Units = |ig/m0
    Avgof48-h PM25
    Child 40.2
    Adult 29.2
    Method: HI, Units = |ig/m0
    Avgof48-hPM2.5:16.2
    Method: HI, Units = |ig/m°
    Avgof48-hPM2.5:19.2
    Wu et al. (2005,157155)
    Alpine, CA
    Method :pDR, Units = |ig/m°
    n11
    Avgof24-hPM25 11.4(7.8)
    Method :pDR, Units = ng/m°
    n14
    Avgof24-hPM2.55.6(2.9)
    
    Method: HI
    n14
    Avgof24-hPM259.8(2.5)
    Method :pDR, Units = ng/m°
    n8
    Avgof24-hPM2.5 14.0(11.4)
    
    Method: HI
    n8
    Avgof24-hPM2.5 14.3(7.8)
    December 2009
                            A-320
    

    -------
            Reference / Location
                Personal
                               Micro
                 Ambient
    NORTHWEST
    Jansenetal.  (2005. 082236)
    Seattle, Washington, USA
                                        NR
                                      Method: HI, Units = ng/m°
                                      Indoor home:
                                      PM1011.93
                                      PM2.5 7.29
    
                                      Outdoor home:
                                      PM1013.47
                                      PM;.5 10.47	
                                                   Method: HI, Units = |ig/m°
                                                   PM1018.0
                                                   PM25  14.0
    Koenig et al. (2003,156653)
    Seattle, WA	
    13.4 ±3.2 ug/m°
                                                                          Inside homes = 11.1 ±4.9
                                                   Outside homes = 13.3 ±1.4
                                                   3 Central-sites = 10.1 ±5.7
    Liu Setal. (2003.073841)
    Seattle, WA
    Summary of PM concentrations
    (ug/m3) between October 1999 and
    May 2001 by study group.
    
    Group Mean ± SD Personal PM25
    COPD 10.5 ± 7.2 Healthy 9.3 ± 8.4
    Asthmatic 13.3 ± 8.2 CHD 10.8 ± 8.4
                Summary of PM concentrations (ug/m")
                between October 1999 and May 2001 by
                study group.
                Group Mean ±SD
                Indoor
                PM2.5
                COPD 8.5 ±5.1
                Healthy 7.4 ±4.8
                Asthmatic 9.2 ±6.0
                CHD 9.5 ±6.8
                PM10
                COPD 14.1 ±6.6
                Healthy 12.7 ±7.8
                Asthmatic 19.4 ±11.1
                CHD 16.2 ±11.3
    Summary of PM concentrations (ug/m")
    between October 1999 and May 2001 by
    study group.
    Location Pollutant
    Group Mean ±SD
    Outdoor PM2 5
    COPD 9.2 ±5.1
    Healthy 9.0 ±4.6
    Asthmatic 11.3 ±6.4
    CHD 12.7 ±7.9
    PM10
    COPD 14.3 ±6.8
    Healthy 14.5 ±7.0
    Asthmatic 16.4 ±7.4
    CHD 18.0 ±9.0
    Mar etal. (2005.087566)
    Seattle, WA USA
    Method: HI, Units = |ig/m°
    PM2.5:
    Healthy: 9.3 (8.4)
    CVD: 10.8(8.4)
    COPD: 10.5 (7.2)
                Method: HI, Units = |ig/m0
                PM2.5:
                Healthy: 7.4 (4.8)
                CVD: 9.5 (6.8)
                COPD: 8.5 (5.1)
    
                PM10:
                Healthy: 12.7(7.8)
                CVD: 16.2(11.3)
                COPD: 14.1 (6.6)
    Method: HI, Units = |ig/m°
    PM2.5:
    Healthy: 9.0 (4.6)
    CVD: 12.7 (7.9)
    COPD: 9.2 (5.1)
    
    PM10:
    Healthy: 14.5(7.0)
    CVD: 18.0(9.0)
    COPD: 14.3 (6.8)
    Trenga et al. (2006,155209)
    Seattle, Washington
    Method: PEM, Units = |ig/m°
    Median PM25
     Child 11.3
     Adult 8.5
                Method: HI, Units = |ig/m°
                Median PM25
                Child 7.5
                Adult 7.6
    Method: HI, Units = |ig/m°
    Residential Outdoor
    Median PM2 5
    Child 9.6
    Adult 8.6
    Residential Outdoor
    Median PMcoarse
    Child 4.7
    Adult 5.0
    Residential Outdoor
    Median PM2 5 central site
    Child 11.2
    Adult 10.3
    Wu et al. (2006,179950)
    Pullman, WA	
    During non-burning times: 13.8 (11.1)
    During burning episodes: 19.0 (11.8)
    SOUTHCENTRAL
    Turpin et al. (2007,157062)
    Houston (and Elizabeth, NJ, and Los
    Angeles County, CA)	
    Houston, Units = ng/m°
    Child: 36.6
    Adult: 37.2
    avg)
                Houston: 17.1
                                                   Houston: 14.7
    December 2009
                             A-321
    

    -------
             Reference / Location
                 Personal
                    Micro
                  Ambient
    MIDWEST
    Adgate et al. (2002, 030676)
    Battle Creek, East St. Paul, and Phillips,
    Minnesota, constituting the Minneapolis-
    St. Paul metropolitan area.
    PM2.5, Units = |ig/m
    
    Battle Creek
    All Seasons: 118,22.7, (25.7), 16.2
    (2.2)
    Spring: 41, 26.3 (25.7), 19.4 (2.1)
    summer: 31,28.5 (36.1), 20.3 (2.1)
    Fall 46,15.5 (13.4), 11.9(2.1)
    
    E. St. Paul
    All Seasons: 107,30.5 (38.7), 20.6
    (2.3)
    Spring: 44, 33.9 (34.4), 23.9 (2.3)
    summer:25,20.5 (15.0),17.2 (1.8)
    Fall: 38, 33.1 (51.9), 19.5(2.5)
    
    Phillips
    All Seasons: 107,26.5 (24.3), 20.9
    (2.0)
    Spring: 28, 37.5 (37.6), 30.0 (1.8)
    summer:40,22.7 (15.3),19.2 (1.7)
    Fall: 39, 22.7 (16.7),. 17.6 (2.1)
    PM2.5, Units = |ig/m
    
    Battle Creek
    All Seasons: 108,10.6 (6.6), 9.0 (1.8)
    Spring: 25,12.7 (7.7), 11.0(1.7)
    summer: 36,8.9 (3.8), 8.1 (1.5)
    Fall: 47,10.9 (7.4), 8.8 (2.0)
    
    E. St. Paul
    All Seasons: 97,17.4 (20.3), 12.2 (2.2)
    Spring: 30, 20.7 (26.4), 13.6 (2.4)
    summer: 26,15.8 (11.4), 13.7 (1.6)
    Fall 41 16.019.610.42.4
    
    Phillips
    All Seasons: 89,14.2 (13.0), 11.3 (1.9)
    Spring: 15,16.9 (14.2), 13.0 (2.1)
    summer: 36,13.2 (6.4), 11.4 (1.7)
    Fall: 38,14.4 (16.7), 10.6(2.0)
    PM2.5, Units = |ig/m
    
    Battle Creek
    All Seasons: 88 9.4 (6.2), 7.8 (1.8)
    Spring: 36,10.5 (7.1), 8.5 (2.0)
    summer: 22, 8.7 (4.4), 7.8 (1.6)
    Fall: 30,8.4 (6.2), 7.1  (1.7)
    
    E. St. Paul
    All Seasons: 95,10.8 (6.6), 9.3 (1.8)
    Spring: 36,12.0(7.3), 10.1 (1.9)
    summer: 25, 8.5 (3.2), 7.8 (1.6)
    Fall: 34,11.3 (7.5), 9.6 (1.8)
    
    Phillips
    All Seasons: 88,10.0 (5.8), 8.7, (1.7)
    Spring: 30 (12.1), 7.2 (10.5)
    summer: 30, 8.6 (3.8), 7.8 (1.6)
    Fall: 28,9.3 (5.5), 8.1  (1.7)
    Crist et al. (2008,156372)
    Ohio River Valley near Columbus
    PM2s, Units = |ig/m°
    Athens (rural): 17.61 (17.81)
    Koebel (urban): 14.59 (13.05)
    New Albany (suburb): 13.93 (12.25)
    PM2.5, Units = |ig/m°
    Indoor
    Athens (rural): 17.20 (13.56)
    Koebel (urban): 14.98 (12.30)
    New Albany (suburb): 16.52 (13.53)
    PM25, Units = |ig/m°
    Athens (rural): 13.66 (8.91)
    Koebel (urban): 13.89 (9.29)
    New Albany (suburb): 12.72 (8.86)
    Sarnatetal. (2006, 089784)
    Steubenville, OH
    Mean (SD):PM15, Units = |ig/m°
    
    Summer
    n = 169
    mean(SD) = 19.9(9.4)
    
    Fall
    mean (SD) = 20.1 (11.6)	
                                          Mean (SD):PM15, Units = |ig/m°
    
                                          Summer
                                          n = 65
                                          mean (SD) = 20.1 (9.3)
    
                                          Fall
                                          mean (SD) = 19.3 (12.2)
    SOUTHEAST
    Wallace and Williams (2005, 057485)
    Raleigh, North Carolina
    Units = |ig/m°
    PM25pers = 23.0(16.4)
    PM2.5 pers/PM15 out =1.31 (0.99)
    Units = |ig/m°
    PM25 in =19.4 (16.5)
    PM2.5 in/PM15 out = 1.08 (1.05)
    Units = |ig/m°
    PM2.5 out = 19.5 (8.6) 18.1 (8.1)
    Williams etal. (2003.053338)
    SE Raleigh, North Carolina
    Chapel Hill, North Carolina
    Pooled PM mass concentrations
    (ug/m) across all subjects,
    residences, seasons, and cohorts
    
    Variable N Geo mean Mean RSD(a)
    Personal PM2.5(b) 712 19.2 23.0 70.1
    
    (a) Relative standard deviation of the
    presented arithmetic mean.
    (b) measured using PEMs.
    Pooled PM mass concentrations (ug/m°)
    across all subjects, residences, seasons,
    and cohorts
    
    Variable N Geo mean Mean RSD(a)
    Indoor PM25 (c) 761,15.3,19.1,80.1
    Outdoor PM25 (c) 761,17.5,19.3,43.7
    Indoor PM10 (b) 761,23.2,27.7,70.6
    Outdoor PM10 (b) 761,27.5,30.4,46.4
    Indoor PM10.25(d) 761,6.3,8.6,111.8
    Outdoor PM10.2.5 (d) 761, 8.5,11.1,  86.9
    
    (a) Relative standard deviation of the
    presented arithmetic mean.
    (b) measured using PEMs.
    (c) measured using HI samplers.
    (d) measured by difference in PEM PMio
    monitor and co-located HI PM2.5 mass
    concentrations.
    Pooled PM mass concentrations (ug/m°)
    across all subjects, residences, seasons,
    and cohorts
    
    Variable N Geo mean Mean RSD(a)
    Ambient PM25 (c) 746,17.3,19.2, 44.9
    Ambient PM10 (b) 752, 27.9,31.4,51.5
    Ambient PM10.2.5(d) 210,8.6,10.0,62.3
    
    (a) Relative standard deviation of the
    presented arithmetic mean.
    (b) measured using PEMs.
    (c) measured using HI samplers.
    (d) measured by difference in  PEM PM^
    monitor and co-located HI PM2.5 mass
    concentrations.
    December  2009
                               A-322
    

    -------
            Reference / Location
                 Personal
    Micro
    Ambient
    NORTHEAST
    Koutrakis et al. (2005, 095800)
    Baltimore, MD Boston, MA
    PM2.5, Units = ng/m°:                   NR
    
    (Baltimore, Boston)
    Winter: Seniors: 15.1 (14.6), 14.1 (6.0)
    Children: 24.0 (21.8), 18.5(12.8)
    COPD: 16.4 (12.7), NR
    Summer: Seniors: 22.1 (10.1), 18.8
    (9.7)
    Children: 18.6 (8.1), 30.3 (14.2)
    COPD:NR, NREC:
    
    (Baltimore, Boston)
    Winter: Seniors: NR, 1.4(0.9)
    Children: 2.8 (1.8), 1.6(1.6)
    COPD: 2.0(1.2), NR
    Summer: Seniors: NR, NR
    Children: NR.NR
    COPD:NR, NRS04:
    
    (Baltimore, Boston)
    Winter: Seniors: 1.9 (1.1), 1.9(1.2)
    Children: NR, 2.3(1.7)
    COPD: 1.5 (0.8), NR
    Summer: Seniors: 5.7 (3.5), 2.9  (1.9)
    Children: NR, NR
    COPD:NR,NR	
                         PM2.s, Units = |ig/m :
    
                         (Baltimore, Boston)
                         Winter:
                         All: 20.1 (9.4), 11.6 (6.8)
                         summer:
                         Seniors: 25.2 (11.5), 12.7(5.4)
                         Children: 23.2 (14.0), 17.0 (11.5)
                         COPD: NR, NREC:
    
                         (Baltimore, Boston)
                         Winter:
                         All: 1.2 (0.6)
                         summer: NR, NRS04:
    
                         (Baltimore, Boston)
                         Winter:
                         All: 4.0 (1.7), 3.1 (1.8)
                         summer:
                         Seniors: 10.5 (7.1), 3.1  (1.8)
                         Children: NR, 6.5 (6.0)
    Sarnat etal. (2005. 087531)
    Boston, Massachusetts. Comparisons to a
    previous study in Baltimore are made.
    Units = |ig/rrf:
    
    Winter-Children:
    PM25:17.4-25.8
    S04:1.6-3.3
    
    Winter-Seniors:
    PM25:10.8-16.2
    S04:1.6-2.6
    
    Summer-Children
    PM25:25.4-32.8
    S04:2.7-3.3
    
    Summer-Seniors
    PM25:17.8-20.5
    S04:2.7-3.3
                                                                            NR
                         Units =|ig/rrf:
    
                         Winter:
                         PM25:6.5-15.5
                         S04:1.7-4.2
    
                         Summer:
                         PM25:11.9-21.4
                         S04:3.6-9.0
    Turpin etal. (2007,157062)
    Elizabeth, NJ, (and Houston, TX, and Los
    Angeles County, CA+
    48-h avg PM25, Units = |ig/m :
    Elizabeth
    Child: 54.0
    Adult: 44.8
                                                                            Elizabeth: 20.1
                                                                                                                Elizabeth: 20.4
    December 2009
                              A-323
    

    -------
    Table A-62.    Summary of PM species exposure studies.
    Reference Particle Sizes Measured Component Results
    Adgate et al. (2007, 156196) Personal, Micro, and Ag.AI, Ca, Cd.Co, Cr, Cs, Median, units :ng/m3:
    Ambient: PM25 - broken down Cu, Fe, K, La, Mg, Mn, Na,
    intoTE Ni.Pb, S,Sb, Sc.Ti.TI, V,Zn Outdoor, Indoor, Personal
    5334.4,272.1,351.6
    Ca 232.2,85.0, 174.1
    Al 96.3,23.3, 58.6
    Na 11 1 9(1 fi 11 Q-
    INd OO. I , ŁU.U, O I .3,
    Fe12.6, 43.1, 78.6
    Mg 10.9, 16.3, 27.5
    K ? 9 ?8 4 47 5
    l\ O.t, OO.t, *T( .O
    Ti7 n n A 14
    1 10. U, U.O, 1 .*f
    7n9 7 fi 5 Q fi
    Z-ii 1. / , o.vj, y .u
    PM 9 4 1 ^ 4 Q
    OU Ł .*T, I .O, *T.J?
    MIMA fl 1 1 A
    INIINM -U.I, I .0
    me 9 4 Q 9
    .vJ, t .*T, O.t
    Mn n fi 1 5 9 ?
    I VI 1 1 U.U, I .U, Ł.O
    Sb 0.08,0.21, 0.30
    Cd 0.05, 0.12, 0.14
    V0.05, 0.12, 0.16
    LaO.02, 0.05, 0.11
    Cs 0.00, 0.00,0.00
    Th 0.00, 0.00, 0.00
    Sc 0.00, 0.00, 0.01
    Ag 0.00, 0.07, 0.08
    Co NA0.02, 0.07
    Cr -0.09, 1.2, 2.6
    Brunekreefetal.(2005, Personal, Micro & Ambient: N03" Mean (SD), units = ng/m3:
    090486) PM2.5 „ , J
    Primary Findings
    The relationships among P, I,
    and 0 concentrations varied
    across TEs. Unadjusted mixed-
    model results demonstrated
    that ambient monitors are more
    likely to underestimate than
    overestimate exposure to many
    of the TEs that are suspected
    to play a role in the causation
    of air pollution related health
    effects. These data also
    support the conclusion that TE
    exposures are more likely to be
    underestimated in the lower
    income and centrally located
    PHI community than in the
    comparitively higher income BC
    K community. Within the limits
    of statistical power for this
    sample size, the adjusted
    models indicated clear
    seasonal and community
    related effects that should be
    incorporated in long-term
    exposure estimates for this
    population.
    In both cities, personal and
    indoor PM2 5 were lower than
    Brunekreefetal.(2005,
    090486)
    Personal, Micro, and
    Ambient: PM2.5
    S(V~, N03"
    Amsterdam:
    Personal 1389(1965)
    Indoor 1348(1843)
    outdoor 4063(4435)
    
    Helsinki:
    Personal 161 (202)
    Indoor 267 (215)
    Outdoor 1276(1181)
    
    Mean, units = ug/m3:
    S042":
    P,  I, 0
    Amsterdam 4.6 4.7 5.9
    Helsinki 2.7 3.0 5.0
    
    N03":
    P, I, 0
    Amsterdam 1.4 1.4 4.0
    Helsinki 0.2 0.3 1.3
                                                                                                               highly correlated with outdoor
                                                                                                               concentrations. For most
                                                                                                               elements, personal and indoor
                                                                                                               concentrations were also highly
                                                                                                               correlated with outdoor
                                                                                                               concentrations.
    In both cities personal and
    indoor PM2.5 were lower than
    highly correlated with outdoor
    concentrations. For most
    elements, personal and
    indoor concentrations were
    also highly correlated with
    outdoor concentrations.
    Chillrud et al. (2004, 054799)  Personal: PM2.
                               Micro :PM2.5
                               Home indoor and home
                               outdoor
    
                               Ambient: Urban fixed-site and
                               upwind fixed site operated for
                               three consecutive 48-h
                               periods each week.
                               Elemental iron, manganese,
                               and chromium are reported in
                               this study out of 28 elements
                               sampled.
                               Mean of duplicate samples:
                               PM2.5:62ug/m3
                               Fe:26 ug/n?
                               Mn: 240 ng/m3
                               Cr: 84 ng/m3
                               Variability: 1-15%
                               Personal samples had
                               significantly higher
                               concentration of iron,
                               manganese, and chromium
                               than home indoor and
                               ambient samples. The ratios
                               of Fe (ng/ ug of PM2.5) vs Mn
                               (pg/ ug PM2.5) showed
                               personal samples to be twice
                               the ratio for crustal material.
                               Similarly for the Cr/Mn ratio.
                               The ratios and strong
                               correlations between pairs of
                               elements suggested steel
                               dust as the source. Time-
                               activity data suggested
                               subways as a source of the
                               elevated personal metal
                               levels.
    December 2009
                                         A-324
    

    -------
            Reference
    Particle Sizes Measured
    Component
    Results
    Primary Findings
    Ebeltetal. (2005,056907)    Personal: PM2.5
                               Micro: "ambient exposure":
                               PM2.5,PM10, PM2.5-io;
                               "non-ambient exposure:"
                               PM2.5
    
                               Ambient: PM2.5, PM10, PM2.5.
                              Ambient SO/,
                              Ambient non-sulfate,
                              Personal sulfate,
                              personal ambient non-sulfate
                        Mean(SD),Units ug/m°
                        Ambient sulfate: 2.0 (1.1),
                        Ambient non-sulfate: 9.3
                        (3.7),
                        Personal sulfate: 1.5 (0.9),
                        personal ambient non-sulfate:
                        6.5 (3.0)
                      Ambient exposures and (to a
                      lesser extent) ambient
                      concentrations were
                      associated with health
                      outcomes; total and
                      nonambient particle
                      exposures were not.
    Farmer etal. (2003,089017) Personal: PM10
    Micro: NR
    A h' t- DM
    AmDieni. riviio
    Extractable organic material
    /Cl"ll\/h
    (tUM)
    BtelP
    LJ[QJI
    cPAHs
    Benzo[a]pyrene (B[a]P)
    Carcinogenic polycyclic
    aromatic hydrocarbons
    (cPAHs)
    
    
    
    Units :ng/m3
    Exposed, controls:
    Prague:
    cPAHs = 12.04(11. 10), 6.17
    (3.48)
    B[a]P= 1.79 (1.67), 0.84
    (0.60)
    Personal exposure to B[a]P
    and to total carcinogenic
    PAHs in Prague was two fold
    higher in the exposed group
    compared to controls, in
    Kosice three fold higher, and
    in Sofia 2.5 fold higher.
    
                                                                                     Kosice:
                                                                                     cPAHs = 21.72(3.12),6.39
                                                                                     (1.56)
                                                                                     B[a]P= 2.94 (1.44), 1.07
                                                                                     (0.66)
    
                                                                                     Sofia:
                                                                                     cPAHs = 93.84 (55.0) police,
                                                                                     94.74 (120.34) bus drivers,
                                                                                     41.65(33.36)
                                                                                     B[a]P=4.31 (2.6) police, 5.4
                                                                                     (3.18) bus drivers, 1.96 (1.53)
    Farmer etal. (2003,089017) Personal: PM10
    Micro: NR
    Ambient: PM10
    PM2.5 (not reported)
    
    
    
    PM10
    EOM
    EOM2
    B[a]P
    c-PAHsb
    
    
    
    Prague-SMWinter Summer
    EOM (ug/m3) 14.93 4.96
    EOM2 (%)23.9 13.4
    B[a]P (ug/m3)3.5 0.28
    c-PAHsb (ug/m3) 24.69 2.29
    Prague-LB Winter Summer
    EOM (ug/m3) 10.86 3.72
    EOM2 (%)27.9 14.1
    B[a]P (ug/m3)2.9 0.17
    c-PAHsb (ug/m3) 20.36 1.32
    Kosice Winter Summer
    EOM (ug/m3) 15.3 1.67
    FDM9 Wn19fid fifl
    Extractable organic matter
    (EOM) per PM10 was at least
    2-fold higher in winter than in
    summer, and c-PAHs over
    10-fold higher in winter than
    in summer Personal
    exposure to B[a]P and to total
    c-PAHs in Prague ca. was 2-
    fold higher in the exposed
    group compared to the
    control group, in Kosice ca. 3-
    fold higher, and in Sofia ca.
    O C fnlrl hinhor
    Ao-Toid nigner.
                                                                                     B[a]P (ug/m3) 1.37  0.15
                                                                                     c-PAHsb (ug/m3) 11.87 1.2
    
                                                                                     Sofia Winter Summer
                                                                                     EOM (ug/m3) 24.6  3.95
                                                                                     EOM2 (%)27.37 13.3
                                                                                     B[a]P (ug/m3)4.84  0.36
                                                                                     c-PAHsb (ug/m3) 36.44 2.43
    Gadkari et al. (2007,156459)  Personal: Respirable PM
                               (RPM)
    
                               Micro: NR
    
                               Ambient: RPM
                              Fe.Ca, Mg, NaK.Cd.Hg,
                              Ni,Cr,Zn,As,Pb, Mn and Li
                        Source contributions varied
                        widely among 12 sites.
    
                        Indoor: 0-95%
                        Ambient: 0-26%
                        Road: 0-94%
                        Soil: 0-75%
                      Authors conclude that personal
                      exposure to ambient RPM is
                      related to local traffic and soil
                      resuspension. They felt that
                      indoor activities or ventilation
                      determined indoor levels of
                      RPM.
    December 2009
                                        A-325
    

    -------
            Reference
     Particle Sizes Measured
           Component
             Results
         Primary Findings
    Gevhetal. (2005. 186949)
    Hanninen et al. (2004,
    056812)
    Ho et al. (2004, 056804)
    Jacquemin et al. (2007,
    192372)
    Personal: TD, PM10, PM2.5 EC
    Micro:NR VOC also assessed
    Ambient: TD, PM10, PM2.5
    Personal: PM25 PM25 -bound S
    Micro: NR
    Ambient: PM15
    Personal: PM25 OC
    EC
    Micro: NR QM
    Ambient: PM2.5 TCA
    Personal: PM15 S
    Micro :NA
    Mean (SD), units = ug/m3:
    Summary Statistics by Area
    Location
    October 2001 :
    Albany and West
    EC 5.9 (NA) OC 36 (NA)
    Liberty and Greenwich
    EC 5.3 (59) OC 30 (56)
    Park Place and Greenwich
    EC 1 4.5 (5. 4) OC 72 (26)
    Church and Dey
    EC 7. 9 (3. 3) OC 48 (15)
    April 2002:
    Liberty and West
    EC 4.2 (2.1) OC 26 (13)
    Barclay and Greenwich
    EC 4.0 (2.6) OC 18 (14)
    Church and Dey
    EC4.5(1.9)OC27(15)
    Middle of the Pile
    EC6.7(1.0)OC40(25)
    IndoorOutdoor
    Athens5.3 (2.0)7.6 (5.1)
    Basel2.6 (1.6)3.3 (1.6)
    Helsinki 1.6 (1.3) 2.2 (1.5)
    Prague 3.1 (1.3)4.0(1.5)
    Mean, Unit = ug/m3
    Indoors:
    OM = 18.1; TCA =22.9
    Outdoors:
    OM = 20.1; TCA =26.5
    Mean, units = ug/m3:
    Personal: 1.3 outdoor: 1.2
    Comparison of recorded EC
    and OC values from October
    2001 and April 2002 with
    previous studies suggests
    that the primary source of
    exposure to EC for the WTC
    truck drivers was emissions
    from their own vehicles.
    Associated with indoor
    concentration: wooden
    building material, city, building
    age, floor of residence (i.e.
    ground, 1st, etc.), and use of
    stove other than electric.
    The major source of indoor
    EC, OC, and PM2.5 appears
    to be penetration of outdoor
    air, with a much greater
    attenuation in mechanically
    ventilated buildings.
    Authors suggest that "outdoor
    measurements of absorbance
    and sulnhur can be used to
    Jansen et al. (2005. 082236)
    Personal, Micro, and
    Ambient: PM2.5
    Estimated Elemental Carbon
    
    Elemental composition of a
    subset of personal, indoor
    and outdoor samples
    Mean (SD), units = ug/m°:
    Amsterdam, Helsinki
    P,0,P,0
    PM2.5 14.5,15.7,9.4,11.4
                                                                                      Zn13.2,18.3,11.7,18.6
                                                                                      Fe57.0, 71.3, 41.6,79.2
                                                                                      K 87.4,70.3,103.1,93.9
                                                                                      Ca 72.9, 40.2, 68.5, 36.4
                                                                                      Cu 5.4,2.5,4.3,1.8
                                                                                      Si 29.7, 13.7,79.5,93.9
                                                                                      CI40.8, 72.7, 9.8,44.2
    estimate both the daily
    variation and levels of
    personal exposures also in
    Southern European
    countries, especially when
    exposure to ETS has been
    taken into account. For PM2.5,
    indoor sources need to be
    carefully considered."
    
    For most elements, personal
    and indoor concentrations
    were lower than and highly
    correlated with outdoor
    concentrations. The highest
    correlations (median r.0.9)
    were found for sulfur and
    particle absorbance (EC),
    which both represent fine
    mode particles from outdoor
    origin. Low correlations were
    observed for elements that
    represent the coarser part of
    the PM25 particles (Ca.Cu,
    Si, Cl).
    December 2009
                                         A-326
    

    -------
    Reference
    Johannesson et al. (2007,
    156614)
    Particle Sizes Measured
    Personal, Micro, and BS
    Ambient: PM2.5, PM,
    Component
    
    Results
    BS2.5 Mean SD
    Personal 0.65 0.47
    Primary Findings
    Personal exposure of PM2.5
    correlated well with indoor
                                                                                        Exclusively smokers 0.62
                                                                                        0.47
    
                                                                                        Residential indoor 0.56 0.47
    
                                                                                        Exclusively smokers 0.52
                                                                                        0.46
    
                                                                                        Residential outdoor 0.68 0.51
    
                                                                                        Exclusively smokers 0.71
                                                                                        0.54
    
                                                                                        Urban background 0.63 0.37
    
                                                                                        All measurements 0.68 0.40
    
                                                                                        PM,/BS1
    
                                                                                        Personal 0.55 0.20
    
                                                                                        Residential indoor 0.54 0.45
    
                                                                                        Exclusively smokers 0.49
                                                                                        0.43
    
                                                                                        Residential outdoor 0.66 0.51
    
                                                                                        Exclusively smokers 0.68
                                                  with residential outdoor and
                                                  urban background
                                                  concentrations were also
                                                  acceptable. Statistically
                                                  significantly higher personal
                                                  exposure compared with
                                                  residential outdoor levels of
                                                  PM2.s was found for
                                                  nonsmokers. PM, made up a
                                                  considerable proportion
                                                  (about 70-80%) of PM2.5. For
                                                  BS, significantly higher levels
                                                  were found outdoors
                                                  compared with indoors, and
                                                  levels were higher outdoors
                                                  during the fall than during
                                                  spring. There were relatively
                                                  low correlations  between
                                                  particle mass and BS. The
                                                  urban background station
                                                  provided a good estimate of
                                                  the residential outdoor
                                                  concentrations of both PM2.5
                                                  and BS2.5 within  the city. The
                                                  air mass origin affected the
                                                  outdoor levels of both PM2.5
                                                  and BS2.5; however, no effect
                                                  was seen on  personal
                                                  exposure or indoor levels.
    Kim etal. (2005,156640) Personal: PM15
    
    Micro: NR
    Ambient: PM15
    
    
    
    
    
    
    
    
    
    Koistinen et al. (2004, Personal, Micro, and
    156655) Ambient: PM15
    
    
    
    
    
    
    
    S042", EC, Ca2*, Mn2*, K, Na* Mean (SD), Units = ug/m3:
    
    S042": 2.7 (3.2)
    Ca2+:0.12(0.12)
    Mg2+: 0.02 (0.01)
    K: 0.07 (0.08)
    
    Na+: 0.09 (0.20)
    
    EC: 0.60 (0.54)
    
    
    
    Black smoke, S042", N03-, % contribution to PM25
    NhV, Al, Ca, Cl, Cu, K, Mg, P, Outdoor - Indoor - Work -
    S,Si,Zn Personal
    CoPM*35,28,32,33
    Secondary** 46, 36, 37,31
    Soil 16, 27, 27, 27
    Detergents 0, 6, 2, 6
    Sea Salt 3, 2, 1,2
    * PnDM io tha Hiffaran^a
    Traffic- related combustion,
    regional, and local crustal
    materials were found to
    contribute 19% ±17%,
    52% ±22%, and 10% ±7%,
    respectively.
    Among participants that spent
    considerable time indoors,
    exposure to outdoor PM2.5
    includes a greater relative
    contribution from combustion
    sources, compared with
    outdoor (ambient) PM2.5
    measurements.
    Population exposure
    assessment of PM2.5, based
    on outdoor fixed-site
    monitoring, overestimates
    exposures to outdoor sources
    like traffic and long-range
    transport and does not
    account for the contribution of
    significant indoor sources.
                                                                                        between total mass and other
                                                                                        identified components; i.e.,
                                                                                        primary combustion particles,
                                                                                        nonvolatile primary and
                                                                                        secondary organic particles,
                                                                                        and particles from tire wear,
                                                                                        water, etc. ** Secondary
                                                                                        particles are the sum of
                                                                                        sulfate, nitrate, and
                                                                                        ammonium. 4 factors were
                                                                                        identified for each exposure
                                                                                        type (residential indoor,
                                                                                        residential outdoor, workplace
                                                                                        indoor, and personal). The
                                                                                        factors contained the
                                                                                        elements AI,Ca,CI, Cu, K,
                                                                                        Mg, P, S, Si, Zn, and black
                                                                                        smoke, (insert in cell to left
                                                                                        after consolidating PM size)
    December  2009
    A-327
    

    -------
    Reference Particle Sizes Measured Component
    Koutrakis et al. (2005, Personal: PM25 Elemental Carbon (EC),
    0958001 S042-
    Micro:NR
    Ambient: PM2.5
    
    
    
    
    
    
    
    
    Kulkarni and Patil (2003, Personal: PM5 Pb
    156664)
    	 Micro: NR Ni
    Ambient: PM5 Cd
    Cu
    Cr
    Fe
    
    Mn
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Results
    Mean (SD) data are provided
    for Baltimore and Boston,
    Units = |jg/m3:
    EC:
    (Baltimore, Boston)
    Winter:
    Seniors: NR, 1.4(0.9)
    Children: 2.8 (1.8), 1.6(1.6)
    COPD:2.0(1.2), NR
    en 2~-
    GW4
    (Baltimore, Boston)
    Winter:
    Seniors: 1.9 (1.1), 1.9 (1.2)
    Children: NR, 2.3 (1.7)
    COPD:1.5(0.8), NR
    Summer:
    Seniors: 5.7 (3.5), 2.9 (1.9)
    Personal samples,
    Units = pg/m3:
    Mean + SD
    Type
    Pb
    Occupational
    4.384 ± 7.766 pg/m3
    Residential
    4.093 ± 5.925 pg/m3
    24-h integrated
    4.205 + 1.523 pg/m3
    PH
    UQ
    Occupational
    0.201 ±0.158 pg/m3
    Rssidsntisl
    0.111 ±0.165 pg/m3
    24-h integrated
    0.1 34 ±0.1 40 pg/m3
    Mn
    IvIM
    Occupational
    1.979 ±7.842 pg/m3
    Residential
    0.1 80 ±0.261 pg/m3
    24-h integrated
    1.983 ±6.824 pg/m3
    
    Occupational
    3.473 ± 4.691 pg/m3
    Residential
    4.589 ± 4.619 pg/m3
    24-h integrated Check
    Primary Findings
    Ambient PM2.5 and S042~ are
    strong predictors of
    respective personal
    exposures. Ambient S04 is
    a strong predictor of personal
    exposure to PM2.5. Because
    PM2.5 has substantial indoor
    sources and S042~ does not,
    the investigators concluded
    that personal exposure to
    S04 accurately reflects
    exposure to ambient PM2.5
    and therefore the ambient
    component of personal
    exposure to PM2.5 as well.
    
    
    
    All listed metals were
    detected in the ambient air
    where as only Lead,
    Cadmium, Manganese, and
    Potassium were detected in
    personal exposures. Mean
    daily exposure to lead
    exceeds the Indian NAAQS
    by a factor of 4.2. However,
    ambient concentration of lead
    conforms to this standard.
    There is a rising trend in the
    personal exposures and
    ambient levels of cadmium.
    However, they are low and do
    not pose any major health
    risk as yet. Personal
    exposures to toxic metals
    exceed the corresponding
    ambient levels by a large
    factor ranging from 6.1 to
    13.2. Thus, ambient
    concentrations may
    underestimate health risk due
    to personal exposure of toxic
    metals. Outdoor exposure to
    toxic metals is greater than
    the indoor (ratios ranging
    from 2.3 to 1.1) except for
    potassium (ratio 0.77).
    However, there is no
    significant correlation
    between these two.
    
    
    December 2009
    A-328
    

    -------
            Reference
     Particle Sizes Measured
           Component
             Results
         Primary Findings
    Lai et al. (2004, 056811)
    Personal, Micro, and
    Ambient: PM2.5
    Ag Cr Mn Si
    Al Cu Na Sm
    As Fe Ni Sn
    BaGaPSr
    BrGePbTi
    CaHgRbTI
    Cd I S Tm
    CIKSbV
    Co Mg Se Zn
    Zr
    GM(GSD), Units: ng/mj
    
    P,RI,RO,WI, I/O
    
    Al 280 (7.0), 67 (7 .2), 22
    (2.9), 110 (7.5), 1.4
    
    As 4.7 (1.6),  3.7(1.8),  2.6
    (2.7), 6(-),1.4
    
    Br 4.7 (2.2), 3.9(2.0), 2.4
    (2.5), 6.2(2.5), 1.6
    
    Ca 260 (2.0), 120(2.1), 30
    (1.6), 280(2.9), 3.3
    
    Cd23(1.4), 19(1.8), 7 (-),
    43 (2.2), -
    
    Cl 400 (3.0),  270 (3.9), 220
    (5. 2), 380 (3. 9), 1.0
    
    Cu 120 (1.3), 88 (1.7), 2.3
    (2.8), 230 (2.1), 37.1
    
    Fe 59(2.3),30(3.8),19(3.5),
     85 (2. 9), 1.6
    
    Ga  0.9 (2.1), 0.6 (2.2), 0.2
    (2.2), 2.0 (3.4), 2.4
    
    K 250 (2. 4), 180 (2. 7), 93
    (2.0),130(4.0),1.7
    
    Mg  260(2.1),130(3.1),140
    (2.9), 120 (2.8), 0.7
    
    Mn  2.1 (2. 6), 1.8 (2. 4) ,2. 2
    (1.5), 3.5 (3.0) ,0.8
    
    Na 21 00 (1.6) ,1800 (1.7),
     11 00 (3 .2), 2700 (1.9), 1.6
    
    NM1 (2.2), 8.6 (2.5), 1 8 (— ),
     23(2.9),—
    
    P 110 (2.1), 70 (2.2), 27(1.8),
     86 (2. 4), 2. 5
    
    Pb 26 (1.7), 19(1.8), 9.4(2.8),
     32(2.0),1.9
    
    S 1200 (1.9),1200 (2.0), 890
    (4.8), 1.2
    
    Se 8.4 (1.5) ,6.8 (1.7) ,2.3
    (1.8), 16 (2. 2) ,2. 8
    
    Si 740 (3.4), 360 (2.9) ,95
    (2.2), 570 (3.8), 2.6
    
    Sn35(1.5),27(1.8),0(-),68
    (2.6),-
    
    Ti 6.2 (1.7) ,2.8 (2.2), 1.1
    (2.0), 6.1 (3.2) ,2.3
    Both the indoor and outdoor
    environments have sources
    that elevated the indoor
    concentrations in a different
    extent, in turn led to higher
    personal exposures to
    various pollutants.
    
    Geometric mean (GM) of
    personal and home  indoor
    levels of PM25,14 elements,
    total VOC (TVOC) and 8
    individual compounds were
    over 20% higher than their
    GM outdoor levels. Those of
    N02,5 aromatic VOCs, and 5
    other elements were close to
    their GM outdoor levels.  For
    PM2.s and TVOC, personal
    exposures and residential
    indoor levels (in GM) were
    about 2 times higher among
    the tobacco-smoke exposed
    group compared to the non-
    smoke exposed group,
    suggesting that smoking is an
    important determinant ofthese
    exposures. Determinants for
    CO were visualised  by real-
    time monitoring, and the
    authors showed that the  peak
    levels of personal exposure
    to CO were associated with
    smoking, cooking and
    transportation activities.
    Moderate to good
    correlations were only found
    between the personal
    exposures and residential
    indoor levels for both PM25
    (r = 0:60; p< 0:001) and N02
    (r = 0:47; p= 0:003).
                                                                                     Zn 18(2.4),15(2.2),13
                                                                                     (2. 5) ,23 (2. 4), 0.9
    December 2009
                                         A-329
    

    -------
    Reference Particle Sizes Measured Component
    Larson et al. (2004, 098145) Personal: PM2.5 Light absorbing carbon (LAC)
    andAI, As, Br, Ca, Cl, Cr, Cu,
    Micro: PM2.5 outside subject's Fe K Mn Ni Pb Sj, s, Ti, V
    residence, and inside
    residence
    Ambient: PM2.5 at Central
    outdoor site (downtown
    Seattle)
    Maitre et al. (2002, 156726) Personal: PM4 PAH, benxene-toluene-
    Micro: NR ^nes (BTX), aldehydes,
    Ambient: PM4 a^ldehydf^6'
    Meng et al. (2005, 081194) Personal: PM2.5 EC, OC, S, Si
    Micro :NA
    Ambient: NR
    Results
    Personal, Rl, RO, Central
    Mass
    10,50010,25012,69311,970
    AI32, 19,21,31
    As1, 1,2,2
    LAC* 1439, 1105, 1830, 1741
    Br 3, 2, 3, 3
    Ca 72, 46, 36, 50
    0248,173,75,78
    Cr2,2, 1,2
    Cu 3, 4, 2, 3
    Fe 63, 35, 61, 95
    K57, 54, 78, 67
    Mn2, 2, 3, 6
    NiO.O, 1, 1
    Pb 2, 2, 5, 5
    Si 109, 65, 66, 62
    S 289, 289, 468, 492
    Ti 4, 3, 3, 6
    VO, 1,2,3
    Median
    Personal Ambient
    Resp ug/m 124, 124 (mean)
    BaPng/m3 0.28,0.1 4
    PAHcng/m31.19,1.56
    PAH ng/m3 13.14,12.26
    Benzene ug/m323.5, 17
    Toluene ug/m3 94.5, 52
    Xylene ug/m3 74, 39
    BTX ug/m3 192, 108
    Formaldehyde ug/m3 21 ,17.5
    Acetaldehyde ua/m3 17, 10.5
    Aldehyde ug/nf 38, 28
    Mean (SD), units = ng/m3:
    Indoor:
    EC: 11 65.9 (2081.0)
    OC: 7725.5 (9359.3)
    5:902.3(602.2)
    51:124.0(79.0)
    Outdoor:
    EC: 1144.1 (968.1)
    OC: 3777.7 (2520.1)
    5:1232.3(633.2)
    51:141.1(171.3)
    Primary Findings
    Five sources of PM2.5
    identified: vegetative burning,
    mobile emissions, secondary
    sulfate, a source rich in
    chlorine, and crustal-derived
    material. The burning of
    vegetation (in homes)
    contributed more PM2.5 mass
    on avg than any other
    sources in all
    microenvironments.
    The occupational exposure of
    policemen does not exceed
    any currently applicable
    occupational or medical
    exposure limits. Individual
    particulate levels should
    preferably be monitored in
    Grenoble in winter to avoid
    underestimations.
    Use of central-site PM2.5 as
    an exposure surrogate
    underestimates the
    bandwidth of the distribution
    of exposures to PM of
    ambient origin.
    December 2009
    A-330
    

    -------
    Reference Particle Sizes Measured Component
    Molnaretal. (2005, 156772) Personal: PM25 BS
    S
    Micro and Ambient: PM10-2.s ci
    and PM2.5 K
    Ca
    Mn
    Fe
    Cu
    Zn
    Br
    Rb
    Pb
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Molnaretal. (2006, 156773) Personal: PM15 and PM, S
    Micro and Ambient: NR CI
    
    Ca
    
    Ti
    
    V
    
    Mn
    FP
    re
    Ni
    
    Cu
    Zn
    
    Br
    
    Pb
    
    
    
    
    
    
    
    
    
    Results
    Median, unit = ng/m3
    Wood burners
    Ref 1 -sided p-value
    BS0.97, 0.74, 0.053
    5880,650,0.500
    
    CI 200, 160,0.036
    
    K 240, 140, 0.024
    Ca 76, 43, 0.033
    Mn 4.8, 3.5, 0.250
    
    Fe 64, 49,0.139
    Cu 8.9, 2.4, 0.016
    Zn 38, 22, 0.033
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Urban background PM25
    Mean, median, range (ng/m3)
    3620,320,95-1900
    CI 97, 54, 25-460
    K55, 50, 32-130
    Ca21, 17,6.6-6.2
    Ti 2.1, 1.9, 1.3-3.8
    V3.4, 2.4, 1.0-13
    Mn 1 6 1 4 0 67- 3 8
    Fe36, 33, 7.1-100
    NI1.6, 1.2,0.33-5.7
    Cu2.1, 1.4,0.33-11
    Zn14, 11,2.8-38
    BM.7, 1.4,0.47-44.3
    Pb 3.3, 2.1,0.94-11
    
    Personal PM25
    Mean, median, range (ug/m )
    S- < 470, 270-1400
    CI 270, 170, 60-920
    K140, 96, 39-690
    Ca110, 80, 27-670
    TM 1,9.5, 3.7-27
    V4.7, 4.0, 2.7-9.4
    Mn---
    Fe68, 69, 23-150
    Ni 4.2, 2.6, 0.89-46
    Cu10, 6.6, 1.1-81
    Zn 21, 16, 6.6-70
    Br2.0, 1.3,0.91-14
    Pb 2.9, 2.6, 0.92-8.3
    Primary Findings
    Statistically significant
    contributions of wood burning
    to personal exposure and
    indoor concentrations have
    been shown for K, Ca, and Zn.
    Increases of 66-80% were
    found for these elements,
    which seem to be good wood-
    smoke markers. In addition, CI,
    Mn, Cu, Rb, Pb, and BS were
    found to be possible wood-
    smoke markers, though not
    always to a statistically
    significant degree for personal
    exposure and indoor
    concentrations. For some of
    these elements, subgroups of
    wood burners had clearly
    higher levels which could not
    be explained by the information
    available.
    Sulfur, one of the more typical
    elements mentioned as a
    wood-smoke marker, showed
    no relation to wood smoke in
    this study due to the large
    variations in outdoor
    concentrations from LOT air
    pollution. This was also the
    case for PM25 mass. Personal
    exposures and indoor levels
    correlated well among the
    subjects for all investigated
    species, and personal
    exposures were generally
    higher than indoor levels.
    PM2 5 personal exposures were
    significantly higher than both
    outdoor and urban background
    for the elements CI, K, Ca, Ti,
    Fe, and Cu. Personal exposure
    was also higher t an indoor
    levels of CI, Ca, Ti, Fe, and Br,
    but lower than outdoor Pb.
    
    Residential outdoor levels were
    significantly higher than the
    corresponding indoor levels for
    Br and Pb, but lower for Ti and
    Cu. The residential levels were
    also significantly higher than
    the urban background for most
    elements.
    
    
    
    
    
    
    
    
    
    
    
    
    
    
                                                                                 Personal PM,
                                                                                 Mean, median, range (ug/m3)
    
                                                                                 S-,< 470, 240-1200
                                                                                 CI-, < 110,54-160
                                                                                 K 80, 82, 50-130
                                                                                 Ca 32, 23, 8.4-87
                                                                                 Ti 6.5,6.3,3.7-11
                                                                                 V-,< 4.2,2.8-8.9
    December  2009
    A-331
    

    -------
            Reference
    Particle Sizes Measured
    Component
                                        Results
    Primary Findings
                                                                                    Mn---
                                                                                    Fe 28, 25, 7.6-68
                                                                                    Ni 8.2,1.2,0.83-58
                                                                                    Cu 5.0, 4.4,1.6-14
                                                                                    Zn15,14, 7.6-37
                                                                                    Br 1.6,1.5,0.83-4.4
                                                                                    Pb 3.6, 2.8,1.1-11
    
                                                                                    Residential Outdoor PM2.5
                                                                                    Mean, median, range
                                                                                    5640,460,190-1800
                                                                                    016.3,140,57-840
                                                                                    K 200,78,32-200
                                                                                    Ca 82, 28, 4.6-85
                                                                                    Ti 34, 5.2, 3.3-21
                                                                                    V6.3,3.9,2.1-14
                                                                                    Mn~
                                                                                    Fe 5.5, 31, 8.8-200
                                                                                    Ni 45, < 1.6, 0.65-5.5
                                                                                    Cu 2.6,1.3,0.65-17
                                                                                    Zn 22,15,5.5-85
                                                                                    Br 2.0, >450,0.91-51
                                                                                    Pb4.6, 2.6, 0.90-20
    
                                                                                    Residential Outdoor PMi
                                                                                    S-, 1.3,24-2000
                                                                                    CI-, < 110,44-170
                                                                                    K 76, 68,  34-170
                                                                                    Ca- < 12, 5.1-78
                                                                                    Ti-,< 5.0, 2.2-9.5
                                                                                    V5.6,4.47,2.2-14
                                                                                    Mn~
                                                                                    Fe 23,14,3.7-140
                                                                                    Ni 3.3,1.4,0.73-28
                                                                                    Cu-< 1.1, 0.73-12
                                                                                    Zn 15,14,5.2-30
                                                                                    Br 1.5,1.4,0.78-4.3
                                                                                    Pb 4.1,1.5,1.0-17
    Na and Cocker (2005,
    156790)
    
    
    Personal: PM2.5 EC, OC
    Micro: NR
    Ambient: PM2.5
    
    Mean (SD), units = ug/m3
    Residential homes: EC 2.0
    (NR)
    OC14.8(NR)
    Hinh school (FCV
    Indoor PM2.5was significant
    influenced by indoor OC
    sources.
    Indoor EC sources were
    predominantly of outdoor
    origin.
                                                                                    Weekday samples 1.1 (0.9)
                                                                                    Weekend samples 1.0 (0.5)
    
                                                                                    High school (OC):
                                                                                    Weekday samples 8.8 (4.7)
                                                                                    Weekend samples 7.4 (2.4)
    Noulett et al. (2006,155999)   Personal: PM15
    
                               Micro: NR
    
                               Ambient: PM15
    ABS (light absorbing carbon)
                                                        Measurement Mean s.d.
    
                                                        Ambient so42" 2.72*3.11
    
                                                        Ambient ABS 1.4** 1.0
    
                                                        Personal S042" 1.33* 1.47
                                                        Personal ABS 1.0** 1.7
    
                                                        * Mean S042" values reported
                                                        in ug/m3
                                                        ** Mean ABS values reported
                                                        in10-5/m"1
                                                  S042" and light absorbing
                                                  carbon concentrations had
                                                  higher personal-ambient
                                                  correlations and less
                                                  variability. This indicates that
                                                  S042" and ABS were of
                                                  outdoor origin, while PM2.5
                                                  mass was of varied indoor
                                                  and outdoor origin.
    December 2009
                                       A-332
    

    -------
    Reference
    Salmaetal. (2007. 113852)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Sarnatetal.(2005RMID
    9171) (2005.087531)
    
    
    
    
    
    
    
    
    
    
    
    
    Sarnatetal. (2006. 089784)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Shilton et al. (2002, 049602)
    
    
    
    
    
    
    Particle Sizes Measured
    Personal: PMi0-2.o and PM2.0
    
    Micro :NA
    Ambient: NR
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Personal: PM15
    
    Micro :N/A
    Ambient: PM15
    
    
    
    
    
    
    
    
    
    
    Personal: PM25
    Micro: NR
    Ambient: PM2.5
    
    
    
    
    
    
    
    
    
    
    
    
    
    Personal, Micro, and
    Ambient: Respirable PM
    
    
    
    
    
    Component Results
    30 elements (Na, Mg.AI.Si, Units: ng/m3:
    P, S,CI, K, Ca,Ti,V,Cr, Mn,
    Fe, Ni, Cu, Zn, Ga, Ge, As, PM10-2.0; PM2.0
    Se.Br, Rb, Sr.Y.Zr, Nb, Mo, Mg 296 130
    Ba.andPb) AI53193
    ' Si 2.09 442
    S 978 828
    Cl 305 104
    K318127
    Ca 2.57 41 3
    Ti 47 25
    Cr3515
    Mn 310 148
    Fe 33.5 15.5
    NI298
    Cu 496 190
    Zn11850
    Br13DL
    Ba145DL
    Pb 47 21
    PM 83.6 33.0
    S04, 03, N02, S02 Correlations between
    personal PM2.5 and ambient
    gas
    03 correlated in summer.
    Spearman's R=0.4,
    Anti-correlated in winter,
    R=0.3-0.1.
    NOX somewhat correlated in
    summer. R=0.3
    Winter, R*0.2-0.4
    S02 not well correlated in
    summer or winter. R=0-0.1 .
    
    CO somewhat correlated in
    summer. R=0. 1-0.3.
    Correlated in winter R=0.2-
    0.3.
    No results were significant.
    S042" Mean (SD), units = ug/m3:
    EC Personal
    Ambient
    S042"
    Summer
    5.9 (4.2)
    7.7 (4.8)
    Fall
    4.4 (3.3)
    6.2 (4.7)
    EC
    Summer
    1.1 (0.6)
    1.1 (0.5)
    Fall
    1.2(0.7)
    1.1 (0.7)
    Respirable PM, metals (Zn, Cu, IndoorOutdoor
    Mn, Al), S042", N03", and Cl" 3
    Cu (ng/m3) 43.3, 24.99
    Mn(ng/m3) 15.6,4.18
    Al (ng/m3) 305.2, 52.90
    S042- (ng/m3) 4.72, 3.47
    Cl (ng/m'*) 1.08, 0.1 5
    N03'(ng/m3).35, 1.08
    Primary Findings
    The concentrations observed
    in the Astoria underground
    station were clearly lower (by
    several orders of magnitude)
    than the corresponding
    workplace limits.
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Substantial correlations
    between ambient PM2.5
    concentrations and
    corresponding personal
    exposures.
    Summertime gaseous
    pollutant concentrations may
    be better surrogates of
    personal PM2.5 exposures
    (especially personal
    exposures to PM2.5 of
    ambient origin) than they are
    surrogates of personal
    exposures to the gases
    themselves.
    
    
    
    
    
    High association between
    personal and ambient S042~
    and EC, especially for S04
    for which there is no
    significant indoor source.
    
    
    
    
    
    
    
    
    
    
    
    
    
    The indoor particulate cone
    was driven by ambient cone;
    meteorological-induced
    changes in ambient PM were
    detected indoors;
    
    
    
    
    December 2009
    A-333
    

    -------
            Reference
    Particle Sizes Measured
    Component
    Results
    Primary Findings
    Smith etal. (2006,156990)    Personal: PM2.5
                               Micro :PM2.s
                               Area samplers in the offices,
                               freight dock, or shop.
                               Ambient: PM2.5
                               Samplers were located in the
                               yard upwind of the terminal.
                              EC
                              OC
                        Work Area EC, OC, EC/TC
                        Office 0.31 (3.72), 11.29
                        (1.63)
                        Dock0.53 (3.24), 5.01 (1.76),
                         3% (3.10)
                        YardO.73 (2.89), 7.77 (1.65),
                         9% (2.49)
                        Shop 1.54 (3.52), 10.37
                        (2.00), 8% (2.21)
                        Non-smokers on-site: 12%
                        (2.13)
                        Clerk  0.09 (9.98), 15.97
                        (1.31)
                        Dock worker 0.76(2.13),
                         13.89(1.45),!% (10.19)
                        Mechanic 2.00 (3.82), 16.89
                        (1.64), 5% (1.96)
                        Hostler 0.88 (3.04), 14.89
                        (1.86), 10% (2.71)
                        Non-smokers off-site 5%
                        (2.09)
                        Pickup/deliver driver 1.09
                        (2.46), 12.40 (1.54)
                        Long haul driver 1.12(1.91),
                         19.26 (2.30),8% (2.13)
                        Smokers On-Site 7% (1.82)
                        Clerk  1.19 (1.70), 32.25
                        (1.70),NR
                        Dock worker 0.98(1.93),
                         24.02(1.87)
                        Mechanic 2.41 (2.27), 24.35
                        (1.78)
                        Hostler 1.74 (2.21), 43.92
                        (2.03)
                        Smokers off-site
                        Pickup & Delivery drivers
                        1.33 (3.84), 24.24 (2.14)
                        Long haul drivers 1.37
                        (2.40),32.81 (3.23)
    December 2009
                                        A-334
    

    -------
            Reference
     Particle Sizes Measured
           Component
             Results
    Primary Findings
    Ssrensen et al. (2003, Personal: PM25 BS Units: 10"6/m
    157000)
    	 Micro: NR n Median Q25-Q75
    Ambient: PM2.5 All 177 6.8 (5.0-13.2)
    Autumn 42 7.1 (6.5-17.2)
    
    Winter 46 8.2 (5.1 -13.3)
    Spring 46 12.6 (5.4-10.4)
    Summer 47 8.1 (3.4-9.0)
    
    
    
    
    
    
    
    Personal PM2.5 exposure was
    found to be a predictor of 8-
    oxodG in lymphocyte DMA.
    No other associations
    between exposure markers
    and biomarkers could be
    distinguished. ETS was not a
    predictor of any biomarker in
    the present study. The current
    study suggests that exposure
    to PM2.s at modest levels can
    induce oxidative DMA
    damage and that the
    association to oxidative DMA
    damage was confined to the
    personal exposure, whereas
    the ambient background
    concentrations showed no
    significant association.
                                                                                                                For most of the biomarkers
                                                                                                                and external exposure
                                                                                                                markers, significant
                                                                                                                differences between the
                                                                                                                seasons were found.
                                                                                                                Similarly, season was a
                                                                                                                significant predictor of SBs
                                                                                                                and PAH adducts, with avg
                                                                                                                outdoor temperature as an
                                                                                                                additional significant
                                                                                                                predictor.
    Sorenson et al. (2005,
    089428)
    Personal: PM25 and BS
    
    Micro: PM25 and BS
    
    Ambient: Street monitoring
    station and roof of a campus
    building PM25 and BS
    BS
    Mean, IQR, Units = ug/m
    
    Personal:
    Cold Season: 10.2 (5.6-14.8)
    Warm Season: 7.1 (5.5-11.4)
    
    Micro:
    Cold Season
    Home Indoor: 6.2 (5.5-11.4)
    Home front door: 10.8 (7.4-
    16.3)
    
    Warm Season
    Home Indoor: 6.1 (3.7-7.6)
    Home front door:
    8.8(5.6-11.54)
    
    Ambient:
    Cold Season: Street Station:
    31.6 (27.5-34.0)
    Urban Background:
    7.7(5.9-11.0)
                                                          Indoor sources of PM and BS
                                                          were shown to be greatly
                                                          influenced by indoor sources.
    
    
    Srametal. (2007, 192084) Personal: PMm, PM,S c-PAHs, BFalP
    Micro: NR
    Ambient: PM10, PM2.5
    
    Warm Season:
    Street Station:
    30.6 (24.7-36.0)
    Urban Background:
    6.8 (4.6-8.6)
    B[a]P:
    Exposed 1 .6 ng/m
    Control 0.8 ng/m3
    c-PAHs:
    Exposed 9.7 ng/m
    Control 5.8 ng/m3
    
    
    Ambient air exposure to c-
    PAHs increased fluorescent
    in situ hybridization (FISH)
    cytogenetic parameters in
    non-smoking policemen
    exposed to ambient PM
    December 2009
                                         A-335
    

    -------
    Reference Particle Sizes Measured Component Results
    Turpinetal. (2007. 157062) Personal: PM2.5 18 volatile organics, 17 For LosAngeles
    carbonyl, PM25 mass and .
    Micro :PM2.5, in the main >23 PM25 species organic Carbon (|jgC/m )
    living area (not kitchen) carbon, elemental carbon, EC 1.4
    Ambient: PM15, in the front or and PAHs Elements (ng/m3)
    backyard
    AgO.5
    Al 24.7
    As 0.5
    Ba 22.9
    Br5.3
    Ca 80.9
    CdO.4
    Cl 62.0
    CoND
    CrO.6
    Cu5.5
    Fe 162.9
    GaO.1
    GeO.1
    HgO.1
    In 0.3
    K74.1
    La 2.3
    Mn2.9
    Mo 0.4
    NI2.0
    Pb4.7
    PdO.3
    P0.1
    RbO.1
    S 1022.9
    Sb2.1
    Se1.4
    Si 128.9
    Sn7.9
    Sr1.8
    TI10.4
    V5.3
    Y0.1
    Zn16.4
    ZrO.5
    Primary Findings
    The best estimate of the
    mean contribution of outdoor
    to indoor PM2.5 was 73% and
    the outdoor contribution to
    personal was 26%.
    Wallace and Williams (2005,   Personal: PM25
    057485)
                                Indoor Micro: PM2.5
    
                                Outdoor Micro: PM2.
                     Mean (SD), units = ng/m :
    
                     Personal: 1046 (633)
    
                     Indoor: 1098 (652)
    
                     Outdoor: 1951 (1137)
    Generally, Finf provides a
    reliable estimate of personal
    exposure. S can be used in lieu
    of personal exposure to PM
    because it is generally derived
    from outdoors.
    Wu et al. (2006, 179950) Personal: PM25 LG Mean personal exposure
    EC (pg/m3):
    Micro:PM25
    OC LG: 0.01 8 (0.024)
    Amhipnt' PM
    r\l 1 lUlcl 11 . rlvl25
    EC: 0.4 (0.5)
    OC: 8.5 (2.7).
    
    Ambient: check component
    During non-burning times:
    0.026 (0.030)
    During burning episodes:
    0.010(0.012)
    
    
    
    
    
    
    
    
    Authors "found a significant
    between-subject variation
    between episodes and non-
    episodes in both the
    Exposure during agricultural
    burning estimates and
    subjects' activity patterns.
    This suggests that the LG
    measurements at the central
    site may not always represent
    individual exposures to
    agricultural burning smoke
    "Evidence of "Hawthorne
    Effect": During declared
    episodes (i.e. real and sham),
    subjects spent less time
    indoors at home and more
    time in transit or indoors
    away from home than during
    non-declared episode
    periods. The differences
    remained even when limited
    to weekdays only.
    December  2009
    A-336
    

    -------
    Reference Particle Sizes Measured Component Results
    Zhao et al. (2007, 1561821 Personal, Micro, and Ambient: EC, Cl, Si, N03 Units = pg/m3:
    PM25
    Personal:
    EC: 1.64
    N03: 0.135
    Si: 0.176
    Cl: 0.116
    i H
    indoor.
    K. -1 Q-IQ
    . i .0 iy
    Nfv nni?
    INW3. U.U I O
    Si: 0.051
    Q1 n roA.
    . U.UZ4
    Outdoor:
    EC: 1.876
    N03: 0.292
    Si: 0.115
    Cl: 0.013
    Primary Findings
    Four external sources and
    three internal sources were
    resolved in this study.
    Secondary N03" and motor
    vehicle exhaust were two major
    outdoor PM25 sources. Cooking
    was the largest contributor to
    the personal and indoor
    samples. Indoor environmental
    tobacco smoking also has an
    important impact on the
    composition of the personal
    exposure samples.
    
    
    
    
    
    Table A-63.   Summary of personal PM exposure source apportionment studies.
    Reference Study Design Results Primary Findings
    Source apportionment of
    personal and indoor central and
    apartment and outdoor PM2 5.
    Hopke et al. (2003, 095544) Ba|(imore re(irement home ^
    10 elderly subjects.
    July-Aug 1998.
    Source apportionment of
    personal and residences and
    central outdoor PM25 around
    Seattle with 10 elderly subjects
    and 10 asthmatic children. The
    Larson etal (2004 098145) purpose of the article was to
    	 compare PMF2 and PMF3
    methods.
    Seattle
    Sep 2000 and May 2001
    Source apportionment of
    personal and residential indoor
    and residential outdoor and
    central outdoor PM2 5,
    Zhao etal. (2006. 156181)
    Raleigh and Chapel Hill NCwith
    38 subjects.
    Summer 2000 and Spring 2001.
    % control P,l, C,0
    External
    Secondary
    SO,1"
    Unknown
    Soil
    46.3,
    13.6,
    2.8,
    64.0,
    14.5,
    3.1,
    79.0,
    17.4,
    3.6,
    64.0
    14.5
    3.1
    nternal
    Gypsum
    Activity
    Personal
    care
    0.7,
    36.2,
    0.4,
    0.4,
    17.8,
    0.3,
    0.0,
    0.0,
    0.0,
    0.0
    0.0
    0.0
    PMF2:
    % control P,l,0
    Veg burn
    Mobile
    Fuel oil
    S, Mn, Fe
    Secondary
    Cl-rich
    Crustal
    Crustal 2
    28.8, 47.6, 56.7
    0.0, 3.6, 7.5
    0.0, 0.0, 6.7
    8.1, 0.0, 0.0
    0.0, 34.5, 20.9
    9.9,3.6, 3.7
    25.2, 10.7, 4.5
    27.9, 0.0, 0.0
    PMF3:
    % control P,l, 0
    Veg burn
    Mobile
    Secondary
    Crustal
    41.0, 57.4, 71.3
    7.2,4.3, 8.2
    19.3, 13.8, 18.0
    32.5, 24,5 2.5
    % control P, 1, R,0
    Motor
    vehicle
    Soil
    Secondary
    S0<2~
    Secondary
    NO,"
    ETS
    Personal
    care and
    activity
    CU-factor
    mix with
    indoor soil
    Cooking
    10.0,
    3.5,
    15.9,
    4.4
    7.0,
    8.0,
    0.4,
    52.5,
    9.4,
    3.7,
    22.5,
    ,4.7,
    10.0,
    19.1,
    1.2,
    53.6,
    17.2,
    9.3,
    59.3,
    61.9
    7.6,
    0.0,
    0.0,
    0.0,
    0.0,
    19.4
    8.5
    
    7.8
    0.0
    0.0
    0.0
    0.0
    63% of personal exposure
    could be attributed to outdoor
    sources (with 46% from S042),
    and resuspension of indoor PM
    during vacuuming, cleaning, or
    other activities contributed 36%
    of personal exposure.
    Results showed that vegetative
    burning was the largest
    contributor to personal
    exposure and that was related
    to outdoor combustion. Crustal
    exposures were related to
    indoor activities.
    Secondary sulfate was the
    largest ambient source and the
    largest ambient contribution to
    personal exposure. Cooking
    produced the largest
    contribution to personal and
    indoor concentrations. Note that
    sums over 100% because
    multiple sources obscured PMF
    resolution.
    December 2009
    A-337
    

    -------
                Reference
            Study Design
                      Results
          Primary Findings
    Meng et al. (2007,194618)
    Source apportioned infiltration for
    personal and residential indoor
    and residential outdoor and
    central outdoor PM2.5.
    
    Los Angeles, Houston, and
    Elizabeth, NJ with 100 non-
    smoking residences and
    residents in each city.
    
    In each season between summer
    1999 and spring 2001 (RIOPA).
    % contrOutdoor Indoor
    (Outdoor Origin)
    Mechanically generated 2,17
    Primary Combustion43,43
    Secondary Formation*55,40
    'excludes nitrates
    Differential infiltration of the
    PM2.5 resulted in a reduction of
    secondary formation products
    relative to outdoors.
    Reffetal. (2007.156045)
    Strand et al. (2006, 089203)
    Functional group distinction for
    personal and residential indoor
    and residential outdoor and
    central outdoor PM2 5, PM25
    samples from 219 homes were
    used for this analysis.
    
    Los Angeles, Houston, and
    Elizabeth, NJ with 100 non-
    smoking residences and
    residents in each city.
    
    In each season between summer
    1999 and spring 2001 (RIOPA).
    S04'~:
    R,0,1, P
    01.0
    10.54-0.761.0
    P 0.54-0.73 0.84-0.901.0
    
    C = 0:
    R,0,1, P
    01.0
    10.12-0.611.0
    P-0.13-0.69 0.07-0.771.0
                                                                     CH:
                                                                     R,0,1, P
                                                                     01.0
                                                                     1-0.08-0.351.0
                                                                     P-0.07-0.190.41-0.851.0
    The main finding was that
    indoor and personal levels of
    CH in organic carbons were
    found to be substantially higher
    than outdoors. This reduced the
    polarity of indoor and personal
    organic carbons
    Source apportionment of
    personal and indoor school and
    outdoor school PM25.
    Zhao et al. (2007, 156182) Denver with 56 asthmatic
    children.
    Oct 2002-March 2003 and Oct
    2003-March 2004.
    % contrP 10
    Secondary
    SO,7"
    Soil
    Secondary
    NOT
    Motor
    vehicle
    Cl-based
    cleaning
    Cooking
    ETS
    4.3
    6.6
    9.4
    13.3
    2.8
    54.8
    9.2
    8.9
    4.2
    2.8
    26.5
    0.4
    30.2
    2.1
    9.6
    12.4
    40.8
    26.5
    0.0
    0.0
    0.0
    The largest personal exposure
    was from cooking (54.8%), but
    motor vehicle emissions were
    the largest outdoor contributor
    (13.3%) to personal exposure.
    Secondary nitrate comprised
    the largest outdoor source but
    accounted for only 9.4% of
    personal exposure.
    Using positive matrix factorization
    and an extrapolation method to
    estimate PM25 based on S042~Fe
    components.
    
    Denver.
    
    Winter 1999-2000 and
    2000-2001.
    Estimation method, Mean (SD, range):
    
    PMF:7.42 (1.93, 3.43-12.89)
    
    Extrapolation Method:
    Using S042": 6.38 (1.60, 3.20-10.97)
    Using S042"and Fe:6.50 (1.36, 3.54-10.12)
    Using S042 and Fe, temperature adjusted: 7.02
    (1.48,3.79-11.02)
    Using S042" (no gamma): 8.23 (2.06, 4.12-14.14)
    Similar results were found with
    each technique.
    December  2009
                                   A-338
    

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    Table A-64.    Summary of PM infiltration studies.
               Reference
             Study Design
                                                                                     Hnf
                                                    I/O
    Allen et al. (2003, 053578)
    Objective: Enhance knowledge of the
    outdoor contribution to total indoor
    and personal PM exposures.
    
    Methods: Continuous light scattering
    monitoring.
    
    Subjects: Elderly and children
    spending most of their time indoors.
    Healthy individuals, elderly with
    COPD or CHD and children with
    asthma. 44 residences measured for
    55 10-day sessions. Seattle, WA.
    PM2.5avg-0.65 ±0.21
    
    Non-heating season- 0.79 ± 0.18
    
    Heating season-0.53 ±0.16
    
    Open windows (mean)- 0.69
    
    Closed windows (mean)- 0.58
    
    All days (mean)- 0.65
    Light scattering (whole peak): 0.75 ±
    0.25
    
    Light scattering (uncensored data):
    0.77 ± 0.24
    
    Sulfur concentration (slope): 0.65 ±
    0.01
    Arhami et al. (2009,190096)
    Objective:To examine associations
    between size-segregated PM, their
    particle components, and gaseous
    co pollutants.
    
    Methods: Data analyzed with linear
    mixed-effect models.
    
    Subjects: Four different retirement
    communities in San Gabriel Valley,
    CAand Riverside, CA. 2005-2007.
    PM2.5:0.38-0.57
    
    EC: 0.64-0.82
    
    OC: 0.60-0.98
                                                                                                       N/A
    Balasubramanian et al. (2007, Objective: PM monitoring and
    156248) assessment based on analysis of
    chemical and physical characteristics of
    indoor and outdoor particles.
    Methods : Particle number and mass
    concentrations measured using real-
    time particle counter and low-volume
    particulate sampler.
    
    Subjects: 3 residential indoor and 1
    residential outdoor environments in
    Choa Chu Kang, Singapore. May 12-
    May23,2004.
    
    
    
    
    
    
    
    
    Barn et al. (2008, 156252) Objective: Measure infiltration factor
    from PM2.s from forest fires and
    determine effectiveness of HEPA
    filter.
    
    Methods: pDR for ambient air
    sampling.
    
    Subjects: Homes affected by forest
    fire or residential wood smoke. British
    Columbia, Canada. 38 homes
    sampled (valid samples : 1 9 winter, 1 3
    summer).
    N/A
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    PM25 (mean)
    Summer:
    HEPA: 0.19 ±0.20
    Unfiltered: 0.61 ± 0.27
    
    Winter:
    HEPA: 0.10 ±0.08
    Unfiltered: 0.28 ±0.18
    
    Both:
    HEPA: 0.13 ±0.14
    Unfiltered: 0.42 ± 0.27
    PM2.5: 0.93-1 .90
    Chemical Species:
    CI": 0.35-0.45
    N02": 2.50-4.13
    N03":1.41-5.41
    S042": 1.21 -1.70
    Na+: 0.43-0.74
    NH4+: 1.43-2.39
    EC: 0.75-0.96
    OC: 1.04-1 .92
    AM. 04-1 .92
    Co: 0.86-1 .32
    Cr: 1.35-2.90
    Cu: 0.50-0.69
    Fe: 0.30-0 .42
    Mn: 0.23-0.42
    Pb: 0.40-2.47
    Zn: 0.59-0.81
    Cd: 0.74-1 .75
    Ni: 0.71-1 .32
    Ti: 0.73-0.78
    V: 1.01-1 .05
    Mean:
    Summer:
    HEPA: 0.43
    Unfiltered: 0.77
    
    Winter:
    HEPA: 0.21
    Unfiltered: 0.36
    
    Both:
    HEPA: 0.25
    Unfiltered: 0.47
    December 2009
                                  A-339
    

    -------
    Reference
    Baxter et al. (2007, 092726)
    
    
    
    
    
    
    
    
    
    Baxter et al. (2007, 092725)
    
    
    
    
    
    
    
    
    
    
    
    Brown etal. (2008.190894)
    
    
    
    
    
    
    Cao et al. (2005, 156321)
    
    
    
    Study Design
    Objective: To develop predictive
    models of residential indoor air
    pollutant concentrations for lower
    SES, urban households. Part of
    ACCESS cohort study of asthma
    etiolooy
    
    Methods: Regression analysis; mass
    balance model; Finffrom slope in
    univariate regression analyses.
    Subjects: Lower SES populations. 43
    homes, 23 homes monitored in both
    seasons, 15 in the non-heating
    season (May-Oct) only, 5 in heating
    season (Dec-Mar ) only; 2003-2005.
    Objective: To predict residential
    indoor concentrations of traffic-
    related air pollutants in lower SES
    urban households. Part of ACCESS
    cohort study of asthma etiology.
    Methods: Regression modeling,
    Bayesian variable selection I/O is
    slope from multivariate model
    Subjects: Lower statuses, urban
    households in Boston, MA. 43 sites
    among 39 households, 66 sampling
    sessions, nonheating (May-Oct) and
    heating (Dec-Mar) 2003-2005
    Objective: To examine if ambient,
    home outdoor, and home indoor
    particle concentrations can be used
    as proxies of corresponding personal
    exposure.
    Methods : Associations characterized
    using univariate mixed effects models
    that included a random subject term.
    Subjects: 15 participants in Boston,
    MA in winter (Nov. 1999-Jan. 2000)
    and summer (June-July 2000).
    Objective: To determine relationships
    and distributions of indoor and outdoor
    PM25, OC, and EC. To determine
    indoor/outdoor sources of indoor
    carbonaceous aerosol.
    Finf
    PM25:0.91±0.23
    EC: 0.72 ±0.49
    Ca: 0.56 ±0.30
    Fe: 0.38 ±0.26
    K: 0.83 ±0.52
    Si: 0.02 ±0.00
    Na: 0.46 ±0.43
    Cl: 0.40 ±0.12
    Zn: 0.85 ±0.28
    S:0.95 ±0.78
    V: 0.60 ± 0.77
    
    
    
    
    
    N/A
    
    
    
    
    
    
    
    
    
    
    
    N/A
    
    
    
    
    
    
    N/A
    
    
    
    I/O
    PM25 (mean, coefficient of variation
    (CV)): 1.14 (0.71)
    EC: 0.89 (0.64)
    Ca: 1.16 (1.90)
    Fe: 0.69 (1.40)
    K: 1.10 (0.95)
    Si: 1.04 (1.31)
    Na: 1.05 (1.84)
    0:3.18(3.79)
    Zn: 0.83 ±(1.13)
    S: 0.76 ± (0.32)
    V: 0.76 ± (0.46)
    
    
    
    
    PM25:
    
    Open Wndows: 0.98
    Closed Wndows: 0.64
    EC: 0.38
    
    
    
    
    
    
    
    PM25:
    
    Wnter: Median: 1.2, Range: 0.8-1.8
    Summer: Median: 0.9, Range: 0.6-1.2
    EC:
    Wnter: Median: 1.1, Range: 0.7-4.5
    Summer: Median- 1.0, Range: 0.9-1.3
    S042':
    Wnter: Median: 0.5, Range: 0.3-0.8
    Summer: Median: 0.8, Range: 0.4-1.0
    20minPM25:
    Roadside: 0.7-4.0
    Urban: 0.9-6.7
    Rural: 0.5-1. 7
    
                                       Methods: Gravimetric analysis to
                                       determine PM2.? concentrations. OC
                                       and EC determined by TOR following
                                       IMPROVE protocol.
    
                                       Subjects: 6 residences in Hong Kong
                                       (2 roadside, 2 urban, 2 rural). March
                                       6-ApriM8,2004.
                                           Roadside: 0.8-1.4
                                           Urban: 1.2-2.0
                                           Rural: 1.0-1.8
    
                                           OC (average and range):
                                           Roadside: 1.9 (1.1-2.3)
                                           Urban: 2.3 (1.5-4.0)
                                           Rural: 1.3 (1.2-2.2)
    
                                           EC (average and range):
                                           Roadside: 1.0 (0.9-1.1)
                                           Urban: 1.1 (0.8-1.3)
                                           Rural: 1.1 (0.9-1.8)
    December  2009
    A-340
    

    -------
                Reference
              Study Design
                                                                                          Hnf
                                                      I/O
    Cortez-Lugo et al. (2008,156368)
    Objective:To determine personal      N/A
    PM2.5 and its relationship with outdoor
    and indoor PM2.5 and PM10.
    
    Methods: Linear regression model
    used to compare personal and indoor
    PM2.5. I/O variation studied using
    analysis of variance and predictors
    determined by generalized estimating
    equation models. I/O PM2.5 ratio
    transformed into natural logarithm.
    
    Subjects: 38 nonsmoking long-time
    Mexico residents with COPD. Mexico
    City, Mexico. Feb-Nov 2000.
                                       PM25:
    
                                       Average: 1.2
    
                                       Range: 0.05-6.1
    Diapoulietal. (2008,190893)
    Objective: To characterize the PM10f
    PM2.5, UFP concentrations at primary
    schools. To examine the relationship
    between indoor and outdoor
    concentrations.
    
    Methods: Chemical analysis of
    collected filters. Regressions to
    examine correlations between indoor
    and outdoor concentrations.
    
    Subjects: 7 primary schools with
    different characterizations of
    urbanization and traffic density in
    Athens, Greece. No ventilation
    system. Nov. 2003-Feb. 2004 and
    Oct.-Dec. 2004.
    N/A
    PM10:0.54-2.46
    
    PM2.5- 0.67-2.77
    
    UFP- 0.33-0.74
    Dimitroulopoulou et al. (2006,
    090302)
    Objective: To develop a probabilistic   N/A
    indoor air model (INDAIR).
    
    Methods: INDAIR predicts frequency
    distributions of concentrations of up to 4
    pollutants simultaneously (N02, CO,
    PMio,  PM25). 3 scenarios: no source,
    gas cooking, smoking.
    
    Subjects: 5 UK sites- Harwell (rural),
    Birmingham East (urban
    background), Bradford (urban
    center), Bloomsbury (urban center),
    Marylebone Road (roadside). Winter
    (October 1-March 31), summer (April
    1-September 30),  1997-1999.
                                       No source:
                                       PM10:0.5-0.65;
                                       PM2.5:0.6-0.7
    
                                       Gas cooking:
                                       PM10:0.6-0.9 (bedroom), 1.0-2.0
                                       (lounge), 1.6-4.3 (kitchen);
                                       PM25:0.74-0.9 (bedroom), 0.9-1.6
                                       (lounge), 1.6-2.9 (kitchen)
    
                                       Smoking:
                                       PM10: 0.7-1.1 (bedroom), 1.1-2.7
                                       (lounge), 1.1-2.5 (kitchen);
                                       PM25:0.8-1.3 (bedroom), 1.3-2.8
                                       (lounge), 1.4-2.6 (kitchen)
    Frommeetal. (2008,155147)
    Objective: To characterize the
    chemical and morphological
    properties of PM in classrooms and in
    corresponding outdoor air.
    
    Methods: PM Finf derived from  sulfate
    Finf and a correction factor that
    results from division of BPM
    (increase of indoor PM per outdoor
    PM, linear relationship) by Bsulf
    (increase of indoor sulfate per
    outdoor sulfate, linear relationship). If
    no indoor source, the sulfate Finfis
    equal to the sulfate I/O.
    
    Subjects: Primary school in northern
    Munich. Densely populated
    residential area 160m away from a
    very busy street. Classrooms had 21-
    23 students. Sampling during
    teaching hours. Oct.-Nov. 2005.
                                                                          N/A
                                       PM,,:
                                       S04?": 0.3,
                                       N03':0.1,
                                       CI": 0.6,
                                       Na2*: 0.9,
                                       NH4*:0.1,
                                       Mg: 0.6,
                                       Ca2*: 1.4,
                                       EC: 0.7,
                                       OC:1.1
                                       PM,5:
                                       SO?': 0.4,
                                       N03":0.2,
                                       CF: 0.5,
                                       Na2*: 0.6,
                                       NH4+:0.3,
                                       Mg: 0.5,
                                       Ca2*: 1.6
    December  2009
                                   A-341
    

    -------
               Reference
              Study Design
                                                                                        Hnf
                                                      I/O
    Guoetal. (2004.156506)1
    Objective:To investigate pollutant
    concentrations at air-conditioned and
    non-air-conditioned markets. To
    compare indoor air quality with the
    Hong Kong standard.
    
    Methods: PMio concentrations
    measured by Hi-Vol sampler
    correlated with corresponding levels
    measured by Dust-Trak monitor.
    
    Subjects: 3  non-air-conditioned and 2
    air-conditioned markets in Hong
    Kong. Sept. 2001-Jan. 2002.
                                                                         N/A
                                       PM10:
    
                                       Non-air-conditioned: -0.7, Air-
                                       conditioned: -0.98
    Hanninen et al. (2004,056812)2
    Objective: To assess indoor PM2.5 by
    origin and potential determinants.
    
    Methods: Part of EXPOLIS study.
    Pump and filter with gravimetric
    analysis.  Univariate single and
    stepwise-multiple regression
    analyses.
    
    Subjects: Residential homes in
    Athens, Greece; Basle, Switzerland;
    Helsinki, Finland; Prague, Czech
    Republic. Homes by city: Athens 50,
    Basle 50, Helsinki 189, Prague 49.
    PM25(mean):
    Athens-0.70 ±0.12
    Basle-0.63 ±0.15
    Helsinki-0.59 ±0.17
    Prague-0.61 ±0.14
    
    S (mean):
    Athens-0.82 ±0.14
    Basle-0.80 ±0.19
    Helsinki-0.70 ±0.20
    Prague-0.72 ±0.16
    PM25:
    Athens: -0.84
    Basle:-1.37
    Helsinki:-1.30
    Prague:-1.33
    
    S:
    Athens:~0.70
    Basle: -0.80
    Helsinki: -0.74
    Prague: -0.77
    Ho et al. (2004, 056804)3
    Objective: PM2.5, OC, and EC
    exposure assessment of occupied
    buildings located near major
    roadways under natural ventilation
    (NV) and mechanical ventilation
    (MV).
    
    Methods: Co-located mini-volume
    samplers and Partisol model 2000
    sampler with 2.5 micron inlet.
    IMPROVE TOR carbon analysis.
    
    Subjects: Occupants of MV (1
    classroom and office) and NV (3
    residences) buildings located within
    10m of major roadway; Hong Kong,
    China. Sep. 2002-Feb. 2003.
    PM25:0.42
    EC: MV: 0.42, NV: 0.76
    OC: MV: 0.66, NV: 0.71
    PM25 (average): 0.2-1.6
    MV (average): <0.7
    NV (average): 0.6-1.6
    EC: Range: 0.5+0.1-1.1+0.4
    OC: Range: 0.6+0.2-1.5+1.0
    Hoek et al. (2008,156554)
    Objective: Exposure assessmentof
    indoor/outdoor particle
    relationships.RUPIOH study.
    
    Methods: Sampling by condensation
    particle counters and Harvard
    impactors. Gravimetric analysis and
    reflectance. Calculations performed
    for 24h avg concentrations. Finf
    estimated by linear regression
    analysis.
    
    Subjects: 4 European cities (Helsinki,
    Finland; Athens, Greece; Amsterdam,
    The Netherlands; Birmingham,
    England). Urban populations. >35yrs.
    Asthma  or COPD. Non-smoking
    households. Work <16h/wk outside
    home. 153 homes sampled Oct.
    2002-Mar. 2004.
    Regression slope for indoor vs. central   N/A
    site outdoor:
    
    PM25: 0.30-0.51
    
    PM10:0.17-0.41
    
    PM10-2.5:0.01-0.17
    
    S042": 0.59-0.78
    
    Soot: 0.43-0.87
    
    Regression slope for indoor vs.
    residential outdoor:
    
    PM2.5:0.34-0.48
    
    PM10:0.26-0.44
    
    PM10-2.5:0.11-0.16
    
    Soot: 0.63-0.84
    December  2009
                                   A-342
    

    -------
               Reference
              Study Design
                                                                                        Hnf
                                                      I/O
    Hopke et al. (2003, 095544)
    Objective: To use advanced factor
    analysis models to identify and
    quantify PM sources. 1998 BPMEES
    data.
    
    Methods: PEM, outdoor and indoor
    sampling of unoccupied apartment in
    retirement facility. PMF used to derive
    source contributions. Multilinear
    Engine used to derive joint factors.
    
    Subjects: 10 non-smoking elderly
    subjects of mean age  84 who did not
    cook.Towson, MD. July 26-Aug. 22,
    1998.
    N03"-SO/:0.03
    
    S042': 0.38
    
    OC: 0.77
    
    MV Exhaust: 0.32
                                                                                                           N/A
    Hystad et al. (2008,190890)
    Objective: To explore the feas ibility of  Seattle:
    modeling residential PM2s Finf for
    occupied residences using data       Mean (all>: 0.59 ± 0.21
    readily available for most of North
    America.
                                                                                                           N/A
                                                                         Mean (detached residences): 0.60 +
                                                                         0.20
                                      Methods: Finf calculated by recursive
                                      mass balance model where Finf is a
                                      function of penetration efficiency,
                                      particle removal rate, and air
                                      exchange.
    
                                      Subjects: 46 residences in Seattle,
                                      WA1999-2003. 38 nonsmoking
                                      residences in Victoria,  British
                                      Columbia, Canada 2006. Heating
                                      (Oct.-Feb.) and nonheating (March-
                                      Sept.).
                                      Victoria:
    
                                      Mean (all): 0.62 ± 0.22
    
                                      Mean (detached residences): 0.59 +
                                      0.22
    Klinmalee et al. (2008.190888)
    Objective: To monitor indoor and       N/A
    outdoor pollution in an university
    campus and shopping center.
    
    Methods: PM measured by PEM and
    quartz filters. Analyzed for mass,
    water soluble ions by ion
    chromatography, and black carbon by
    a smokestain reflectometer. I/O
    calculated for each sample pair then
    average taken.
    
    Subjects: University campus and
    shopping center in northern suburb of
    Bangkok, Thailand. Dec. 2005-Feb.
    2006.
                                       PM2.5:
    
                                       University:
    
                                       Weekdays: 0.6, Weekends: 0.5
    
                                       Shopping center:
    
                                       Weekdays: 1.5, Weekends: 2.0
    
                                       BC in PM2.5:
    
                                       University: 0.9
    
                                       Shopping center: 0.67
    December 2009
                                   A-343
    

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                Reference
              Study Design
                                                                                            mf
                    I/O
    Koistinen et al. (2004, 156655)
    Objective:To identify PM2.5 sources in
    personal exposures with principal
    component analysis of the elemental
    compositions in residential outdoor,
    indoor, and workplace indoor
    microenvironments. Part of EXPOLIS
    study.
    
    Methods: Principal component
    analysis to identify sources of
    microenvironmental and personal
    PM2.5 exposure. Specific mass
    contributions of sources calculated by
    source reconstruction.
    
    Subjects: Non-smoking, 25-55yrs.
    Helsinki, Finland. Oct. 1996-Dec.
    1997.
                                                                           N/A
    Median seasonal:
    PM25:
    Wnter: 0.77, Spring: 1.03, Summer:
    0.95, Fall: 0.92, Total: 0.92
    Pb:
    Wnter: 0.67, Spring: 0.56, Summer:
    0.86, Fall: 0.69, Total: 0.67
    S:
    Wnter: 0.60, Spring: 0.63, Summer:
    0.90, Fall: 0.75, Total: 0.69
    
    Wnter: 0.57, Spring: 0.72, Summer:
    0.98, Fall: 0.89, Total: 0.77
    BS:
    Wnter: 0.65, Spring: 0.67, Summer:
    0.91, Fall: 0.88, Total: 0.79
    In:
    Wnter: 0.58, Spring: 0.75, Summer:
    0.66, Fall: 0.75, Total: 0.68
    Fe:
    Wnter: 0.52, Spring: 0.96, Summer:
    0.90, Fall: 0.95, Total: 0.83
    K:
    Wnter: 0.95, Spring: 1.05, Summer:
    1.01, Fall: 1.08, Total: 1.05
    Cl:
    Wnter: 1.01, Spring: 1.24, Summer:
    1.37, Fall: 1.74, Total: 1.24
    Al:
    Wnter: 1.19, Spring: 1.08, Summer:
    1.41, Fall: 2.20, Total: 1.27
    Objective: To establish effects of
    evaporative coolers on indoor PM
    concentrations.
    
    Methods: Concurrent 10min avg
    indoor and outdoor concentrations
    recorded for 2  days.I/O determined
    by equation based on mass
    conversation principles.
    
    Subjects: 10 homes with evaporative
    coolers. El Paso, TX. June 22-Aug.
    23,2001.
                                                                           N/A
    PM10:
    
    All: 0.60
    
    Cooler On: 0.57
    
    Cooler Off: 0.66
    
    PM25:
    
    All: 0.65
    
    Cooler On: 0.63
    
    Cooler Off: 0.73
    Lundenetal. (2008,155949)
    Objective: To investigate the
    physiochemical processes that
    influence the transport and fate of
    outdoor particles to the indoor
    environment.
    
    Methods: I/O calculated from
    measurements of aerosols collected
    on quartz filters.
    
    Subjects: 3-bedroom single-story
    unoccupied house in Clovis, CA. 3
    periods: Oct. 9-23, 2000; Dec. 1-19,
    2000; Jan. 12-23,2001.
                                                                           N/A
    PM25: Oct.: 0.46 ±0.2, Dec.: 0.39 ±0.2,
    Jan.: 0.38 ±0.3, All periods: 0.41 ±0.2
    
    Carbon: Oct.: 0.50 ±0.1, Dec.: 0.46 ±
    0.1, Jan.: 0.52 ±0.2, All periods: 0.50 ±
    0.2
    
    OC: Oct.: 0.48 ±0.1, Dec.: 0.44 ±0.1,
    Jan.: 0.50 ± 0.2, All periods: 0.47 ± 0.2
    
    Black carbon: Oct.: 0.60 ± 0.2, Dec.:
    0.60 ± 0.2, Jan.: 0.65 ± 0.2, All periods:
    0.61 ±0.2
    Macintosh et al. (2009,190887)
    Objective: To estimate the potential
    for residential air cleaning systems to
    mitigate exposure to fine particles of
    ambient origin.
    
    Methods: Multi-zone indoor air quality
    model to examine annual, 24h avg
    and diurnal concentrations of outdoor
    PM2.5 in residential indoor air.
    
    Subjects: Homes in Cincinnati,
    Cleveland, and Columbus, OH that
    have natural ventilation, forced air
    heating and cooling with conventional
    in-duct filtration, or forces air heating
    and cooling with high-efficiency in-
    duct air cleaning. 2005.
                                                                           N/A
    PM2.5 (range):
    
    Natural ventilation: 0.23-0.97
    
    Forced air-conventional filtration:
    0.13-0.94
    
    Forced air-high-efficiency
    electrostatic: 0.02-0.80
    December  2009
                                    A-344
    

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               Reference
             Study Design
                                                                                        Hnf
                                                     I/O
    Martuzevicius et al. (2008,190886)
    Objective: To determine the           N/A
    contribution of traffic-related PM to
    the indoor aerosols.
    
    Methods: Receptor modeling based
    on a  PARAFAC model.
    
    Subjects: 6 houses 30-300mfrom a
    highway, with conventional windows,
    central HVAC, and with smoking and
    cooking allowed. Spring: Mar. 30-May
    14, 2004. Fall: Sept. 13-Oct. 22,
    2004. Cincinnati, OH.
                                      Range- PM25: Spring: 0.5 ± 0.2-2.9 ±
                                      1.2; Fall: 0.7 ±0.1-4.7 ±6.9
                                      EC:
                                      Spring: 0.3 ±0.1-2.2 ±1.7;
                                      Winter: 0.6 ±0.1-1.3 ±0.7
                                      OC:
                                      Spring: 1.0+ 0.7-6.9+ 3.9;
                                      Winter: 1.2 ±0.1-7.6 ±10
                                      Si:
                                      Spring: 0.4+ 0.1-5.1 +3.9;
                                      Winter: 0.5+ 0.1-5.3+ 4.5
                                      S:
                                      Spring: 0.4 ±0.1-0.7 + 0.1;
                                      Winter: 0.5+ 0.1-0.9+ 0.4
                                      Mn:
                                      Spring: 0.3+ 0.2-0.8+ 0.6;
                                      Winter: 0.3+ 0.2-1.0 + 0.2
                                      Fe:
                                      Spring: 0.3+ 0.0-1.3+ 0.8;
                                      Winter: 0.4+ 0.1-0.9+ 0.6
                                      In:
                                      Spring: 0.3 ±0.1-0.7 + 0.6;
                                      Winter: 0.6+ 0.1-1.1 +0.8
                                      Br:
                                      Spring: 0.3+ 0.1-1.0 + 0.5;
                                      Winter: 0.2+ 0.1-0.9+ 0.6
                                      Pb:
                                      Spring: 0.3+ 0.3-0.9+ 0.6;
                                      Winter: 0.2+ 0.2-1.9+ 2.3
    Meng et al. (2005, 058595)
    Objective: Analyses of RIOPAdata,    PM25- 0.46
    which investigated relationships
    between indoor, outdoor, and
    personal exposure for several air
    pollutants.
    
    Methods: PM measured on Teflon
    filters collected by PEMs for 48h. The
    mass balance model and RCS
    statistical model used to estimate
    indoor and and personal PM
    concentrations.
    
    Subjects: 212 nonsmoking homes
    sampled. Houston, TX; Los Angeles
    County, CA; Elizabeth, NJ. Summer
    1999-spring 2001, all 4 seasons.
                                      Los Angeles:
                                      PM25: Mean: 0.84, Median: 0.90;
                                      EC: Mean: 0.93, Median: 0.92;
                                      OC: Mean: 1.32, Median: 1.31
                                      Elizabeth:
                                      PM25: Mean: 0.99, Median: 0.86;
                                      EC: Mean: 1.0, Median: 0.85;
                                      OC: Mean: 2.4, Median: 1.8
                                      Houston:
                                      PM25: Mean: 1.16, Median: 1.02;
                                      EC: Mean: 1.0, Median: 0.71;
                                      OC: Mean: 2.25, Median: 2.35
    Molnaretal. (2007,156774)
    Objective: To characterize and
    compare indoor and outdoor PM2.5
    trace element concentrations in
    difference microenvironments related
    to children.
    
    Methods: Elemental concentrations
    analyzed using X-ray fluorescence
    spectroscopy.
    
    Subjects: 40 sampling sites (10
    classrooms in 5 schools, 10
    preschools, 20 non-smoking homes).
    3 communities in Stockholm,
    Sweden. Sampled once during spring
    and once during winter. Dec. 1, 2003-
    July 1,2004.
    PM25 (containing S or Pb): 0.4-0.9
    S (median):
    
    Both seasons: 0.61  (homes), 0.53
    (schools), 0.69 (preschools);
    
    Winter: 0.47 (homes), 0.36 (schools),
    0.63 (preschools);
    
    Spring: 0.63 (homes), 0.55 (schools),
    0.90 (preschools)
    
    Pb (median):
    
    Both seasons: 0.70 (homes), 0.59
    (schools), 0.70 (preschools);
    
    Winter: 0.62 (homes), 0.43 (schools),
    0.63 (preschools);
    
    Spring: 0.70 (homes), 0.64 (schools),
    0.75 (preschools)
    December 2009
                                   A-345
    

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               Reference
             Study Design
                                                                                       Hnf
                                                     I/O
    Ngetal. (2005,155996)
    Objective:To estimate PM exposures  N/A
    following the September 11,2001
    attack in NYC.
    
    Methods: Outdoor PM25 interpolated
    and used in a deterministic micro-
    environmental model (INTAIR) to
    simulate analytically concentrations in
    indoor micro-environments. Linear
    regression equations used.
    
    Subjects: Lower Manhattan residents
    divided into representative  individuals
    - home-maker, office/shop-worker,
    student/child. Estimates Sept. 14-31.
                                      Mean I/O in home simulated with
                                      INTAIR:
                                      No Source: 0.6
                                      Smoking: 1.9
                                      Cooking: 1.3
                                      Smoking and Cooking: 2.3
                                      I/O of micro-environments simulated
                                      by analytical and empirical methods
                                      (no indoor source):
                                      Office/Shop: 0.4
                                      Classroom: 0.9:
                                      Transport Area: 1.9
                                      Store: 1.2
    Pascholdetal. (2003,156847)
    Objective: To identify PM sources
    inside homes with evaporative
    coolers.
    
    Methods: PM element composition
    analysis by ICP-MS.
    
    Subjects: 10 residences. El Paso, TX.
    Summer 2001.
                                                                        N/A
                                      PM10:
    
                                      Na: 0.33, Mg: 0.43, Al: 0.50, K: 0.48,
                                      Ca: 0.40, Ti: 0.52, Mn: 0.48, Fe: 0.46,
                                      Cu: 0.74, Zn: 0.52, Ba: 0.54, Pb: 0.76
    
                                      PM2.5:
    
                                      Na: 0.20, Mg: 0.29, Al: 0.34, K:0.30,
                                      Ca: 0.52, Ti: 0.40, Mn: 0.35, Fe: 0.30,
                                      Cu: 0.67, Zn: 0.34, Ba: 0.47, Pb: 0.51
    Polidorietal. (2007,156877)
    Objective: To investigate the
    relationships of indoor and outdoor
    PM2.s, its components, seasonal
    variations, and gaseous copollutants.
    PM2.
    Only l/0's<1 considered
                                                                        July 6-Aug. 20:0.71  ±0.10; Aug. 24-
                                                                        Oct. 15:0.60 ± 0.05; Oct. 19-Dec. 10:
                                                                        0.59 ±0.07; Jan. 4-Feb. 18:0.45 ±
                                      Methods: Finf estimated by analysis of  0.06
                                      l/0's and a recursive model
                                      technique.                          OC:
                                      Subjects: 2 retirement facilities in Los
                                      Angeles, CA. July 6-Aug. 20, 2005.
                                      Aug. 24-Oct. 15, 2005. Oct. 19-Dec.
                                      10, 2005. Jan. 4-Feb. 18, 2006.
                                      July 6-Aug. 20:0.86 ± 0.05; Aug. 24-
                                      Oct. 15:0.77 ± 0.09; Oct. 19-Dec. 10:
                                      0.82 ±0.07; Jan. 4-Feb. 18:0.64 ±
                                      0.10
    
                                      EC:
    
                                      July 6-Aug. 20:0.73 ± 0.07; Aug. 24-
                                      Oct. 15:0.71 ±0.05; Oct. 19-Dec. 10:
                                      0.77 ±0.06; Jan. 4-Feb. 18:0.64 ±
                                      0.10
    Ramachandran et al. (2003,195017)
    Objective: To examine variability in    N/A
    measurements of 24h avg and 15min
    avg PM2.5 concentrations.
    
    Methods: Linear regression of
    gravimetric measurements.
    
    Subjects: 3 urban residential
    neighborhoods in Minneaopolis-St.
    Paul, MN. 9-10 nonsmoking
    residences. Spring (April 26-June 2),
    summer (June 20-Aug. 10), fall (Sept.
    23-Nov.20)of1999.
                                      24h avg:
    
                                      Mean: 1.7, Median: 1.3, Standard
                                      deviation: 1.6
    
                                      15minavg:
    
                                      Mean: 2.7, Median: 1.2, Standard
                                      deviation: 8.7
    Rojas-Bracho et al. (2004, 054772)
    Objective:To examine determinants
    of personal exposure to PM2 5, PMio,
    PM2.5-10.
    
    Methods: 2 sets of mixed models.
    Personal  exposures modeled as
    dependent variables. Subject
    variability modeled using random
    effects. Explanatory variables and
    season modeled as fixed effects.
    
    Subjects: 18 COPD subjects in
    nonsmoking households. Boston,
    MA. Winters of 1996 and 1997,
    summer of 1996.
                                                                        N/A
                                      PM2.5:
    
                                      Winter: Mean: 1.58, Median: 2.11;
                                      Summer: Mean: 1.08, Median: 0.88
    
                                      PM10:
    
                                      Winter: Mean: 2.02, Median: 3.77;
                                      Summer: Mean: 1.14, Median: 1.05
    
                                      PM2.5-10:
    
                                      Winter: Mean: 2.65, Median: 3.59;
                                      Summer: Mean: 1.26, Median: 1.39
    December 2009
                                  A-346
    

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               Reference
             Study Design
                                                                                       Hnf
                                                     I/O
    Sarnatetal. (2006. 089166)
    Objective: To assess the ability of
    outdoor PM2.5 its volatile and
    nonvolatile components and particle
    sizes to infiltrate indoors.
    
    Methods: PM2.5 mass contributions
    estimated by the mean concentration
    ratio between each component and
    PM2.5. Indoor and outdoor particle
    concentrations relationships
    examined by Spearman correlation
    coefficient. I/O concentration ratios
    used during overnight (nonsource)
    period to  estimate fraction of ambient
    particles remaining airborne indoors
                                      Subjects: 17 occupied, nonsmoking
                                      Los Angeles, CA residences. July 28,
                                      2001 -Feb. 25, 2002.
    PM2.5:
    
    Median: 0.48, Interquartile range:
    0.39-0.57
    
    BC:
    
    Median: 0.84, Interquartile range:
    0.70-0.96
    
    UFP (0.02-0.03 urn):
    
    Median: 0.50, Interquartile range:
    0.39-0.60
    
    UFP (0.08-0.3 urn):
    
    Median:-0.75
    
    Coarse particles (5-10 urn):
    
    Median: <0.17
    PM2.5:
    
    Overnight: 0.40-0.57, Morning: 0.43-
    0.74, Afternoon: 0.45-0.90, Evening:
    0.42-0.82
    
    BC:
    
    Overnight: 0.70-0.97, Morning: 0.67-
    0.98, Afternoon: 0.77-1.04, Evening:
    0.70-1.01
    Stranger et al. (2008,190884)
    Objective: To assess indoor air
    quality by determining indoor and
    outdoor PM2.5 mass concentrations,
    elemental composition, and gaseous
    compounds.
    
    Methods: PM mass concentrations
    determined gravimetrically.
    
    Subjects: 27 primary schools in city
    center and suburbs of Antwerp,
    Belgium. Dec. 2002 and June 2003.
    N/A
                                      PM2.5:
    
                                      Urban: Range: 0.3-6.9, Average: 1.3;
                                      Suburban: Range: 0.2-8.8, Average:
                                      2.3
    
                                      V, Ni.Zn, Pb, Br, Mn:<1
    
                                      CI,Ca,AI,Si,K,Ti, Fe:>1
    
                                      BS: Urban: Average: Dec.- 0.7 + 0.1,
                                      June-1.1 ±0.3; Suburban: Dec.-0.8 +
                                      0.2, June-1.0 + 0.4
    Stranger et al. (2009,190883)
    Objective: To assess indoor air       N/A
    quality in residences by quantifying
    various gaseous pollutants, and PM
    mass concentrations, elemental
    composition, and water-soluble ionic
    content.
    
    Methods: PM mass concentrations
    gravimetrically determined. Elemental
    bulk analysis on filters.
    
    Subjects: 19 residential homes in
    Antwerp, Belgium that were a subset
    of participants in the ECRHS II study.
                                      PM,: Houses 1-15: Average: 2.0,
                                      Range: 0.3-9.6; Smokers: Average:
                                      3.9, Range: 1 .2-9.7; Non-smokers:
                                      Average: 0.8, Range: 0.3-14
    
                                      PM2.5: Houses 1-15: Average: 1.5,
                                      Range: 0.4-5.4, Smokers average:
                                      2.5, Smokers range: 1 .2-5.4, Non-
                                      smokers average: 0.8, Non-smokers
                                      range : 0.4-1 .3 ; Houses 16-19:
                                      Average: 2.6, Range: 0.3-3.9
    
                                      PM10: Houses 1-15: Average: 1.3,
                                      Range: 0.4-4.1 , Smokers average:
                                      2.1, Smokers range: 1.1-4.1, Non-
                                      smokers average: 0.8, Non-smokers
                                      range: 0.4-1 .2
    
                                      Ca,Ti,V,Cr, Mn.Fe, Ni.Zn, Pb.Si,
                                                                                                          K,Cu,Br,AI:>1
    Turpin et al. (2007,157062)
    Objective: To characterize and
    compare outdoor, indoor, personal
    PM2.5 exposure. Identify indoor and
    personal PM25 sources. Estimate
    outdoor PM2.5 effect on indoor and
    personal PM2.5. RIOPA study.
    
    Methods :Finf calculated in three
    ways: RCS model used to obtain
    constant Finf. Mass balance model
    shows Finf varying with AER. Robust
    regression uses major PM2.5 species
    for home-specific Finf.
    
    Subjects: 309 nonsmoking adults and
    118 children with no preexisting
    conditions. 219 homes sampled.
    Elizabeth NJ, Houston TX, and Los
    Angeles County CA.
    PM2.5:
    
    RCS model: 0.46
    
    Least-Trimmed Squared Regression:
    Mean: 0.69, Median: 0.70,SD:0.23
    
    Mass Balance Model: ~0.08-~0.85
    Los Angeles:
    PM25: Mean: 0.84, Median: 0.90
    EC: Mean: 0.93, Median: 0.92
    OC: Mean: 1.32, Median: 1.31
    
    Elizabeth:
    PM2.5: Mean: 0.99, Median: 0.86
    EC: Mean: 1.0, Median: 0.85
    OC: Mean: 2.4, Median:  1.8
    
    Houston:
    PM25: Mean: 1.16, Median: 1.02
    EC: Mean: 1.0, Median: 0.71
    OC: Mean: 2.25, Median: 2.35
    December 2009
                                   A-347
    

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               Reference
              Study Design
                                                                                        Hnf
                                                      I/O
    Wallace and Williams (2005, 057485)
    Objective: To estimate the
    contribution of outdoor PM2.5 to
    personal exposure in high-risk
    subpopulations.
    
    Methods: Longitudinal regressions of
    estimated indoor and outdoor PM2.5
    for Finf.
    
    Subjects: 29 African-Americans with
    hypertension and 8 with implanted
    cardiac defibrillators. Measured
    7d/season, 4 seasons in 2000-2001.
    Raleigh, NC.
    Range: 0.35-0.87
    PM2.5:
    
    Mean: 1.08 ± 1.05, Median: 0.75,
    Range: 0.24-9.48
    
    S:
    
    Mean: 0.59 ± 0.16, Median: 0.58,
    Range: 0.17-1.06
    Williams etal. (2003,053338)
    Objective:To estimate ambient PM2.5
    contributions to personal and indoor
    residential PM mass concentrations.
    
    Methods: Finf estimated from least
    squares, regression analysis, and
    mixed model slope.
    
    Subjects: Nonsmoking, ambulatory, >
    SOyrs. 2 cohorts: mostly Caucasian
    with implanted cardiac defibrillators in
    Chapel, NC; 30 African-Americans
    with controlled hypertension in low-to-
    moderate SES neighborhoods in
    Raleigh, NC. 7d/season, 4 seasons in
    2000-2001.
    Least squares estimate of indoor
    filtration factors:
    
    Mean: 0.42 ± 0.38, Range: -0.55 to
    1.62
    
    Regression analysis: 0.43 ± 0.06
    
    Mixed model slope: Mean- 0.45 ±
    0.21, Range-0.05-0.94
                                                                                                            N/A
    Williams etal. (2008.191201)
    Objective: To examine the spatial
    variability of PM2.5 and PMiq-2.s and
    their components to determine the
    suitability of conducting health
    outcome studies using a central site
    monitor in a metropolitan area having
    multiple source impacts.
    
    Methods: Gravimetric analysis of PM
    mass concentrations. ED-XRF
    analysis of PM elements.
    
    Subjects: Non-smoking, ambulatory,
    and living in detached homes and
    non-smoking households. Detroit, Ml.
    PM2.5:
    
    Range: 0.16-6.45, Mean: 0.7 ± 0.33,
    Median: 0.70 (indicate indoor sulfur
    source when Finf>1)
                                                                                                            N/A
    Wilson and Brauer (2006. 088933)     Objective: To provide additional       SO/: 0.72
                                       insight into factors affecting exposure
                                       to airborne PM and the resultant
                                       health effects.
    
                                       Methods: Finf estimated by mass
                                       balance equation.
    
                                       Subjects: 16 nonsmoking subjects
                                       with COPD. 54-86yrs. Vancouver,
                                       British Columbia. April-Sept. 1998.
                                                                         N/A
    Wu et al. (2006,179950)
    Objective: To assess personal PM2.5
    exposures from ambient sources and
    agriculture burning smoke.
    
    Methods: Finf estimated by PCS model.
    Application of Robust regression
    algorithm.
    
    Subjects: 33 adult asthmatics. 18-
    52yrs. Pullman, WA. Sept. 3,2002-
    Nov. 1,2002.
    Range: 0.25-0.94
                                                                                                            N/A
    December  2009
                                   A-348
    

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                Reference
              Study Design
                                                                                           Hnf
                    I/O
    Yang et al. (2009,190885)
    Objective: To characterize the         N/A
    concentrations of different indoor air
    pollutants.
    
    Methods: PM10 collected on pall flex
    membrane filer using MiniVol portable
    air samplers. Arithmetic and
    geometric means calculated for
    indoor concentrations. Differences in
    concentrations measured by Kruskal-
    Wallis test.
    
    Subjects: 55 schools in 6
    metropolitan areas in Korea. Samples
    from a classroom, laboratory, and
    computer classroom. 3 seasons,
    July-Dec. 2004.
    PM10:
    
    Classroom: Summer: 1.98, Autumn:
    2.25, Winter: 2.07, Total: 2.06
    
    Laboratory: Summer: 1.33, Autumn:
    1.32, Winter: 1.72, Total: 1.46
    
    Computer classroom: Summer- 0.77,
    Autumn: 1.43, Winter: 2.08, Total:
    1.43
    Zhuetal. (2005.190081)
    Objective:To determine penetration
    behavior of outdoor ultrafine particles
    into indoor environments in areas
    close to freeways.
    
    Methods: Dynamic mass balance
    model.
    
    Subjects: 4 2-bedroom apartments
    within 60m from the center of the 405
    Freeway in Los Angeles, CA. Non-
    smoking tenants. 2 sampling periods
    (non-cooking, non-cleaning): Oct.-
    Dec. 2003 and Dec. 2003-Jan. 2004.
                                                                           N/A
    Highest (largest ultrafine particles-
    70-100nm): 0.6-0.9
    
    Lowest (smallest ultrafine particles-
    10-20nm): 0.1-0.4
     . I/O estimated from Figure 8 in study.
      I/O calculated from indoor and outdoor concentrations in Table 1 in study.
      Fjnf measured by coefficient of determination, R .
    4. RIOPA calculated l/0's.
     . I/O calculated from mean and median indoor and outdoor concentrations listed in Table 1 of study.
    6. l/0's estimated from Figure 3 in study.
      Mean and median I/O concentrations calculated from all residences in study.
     . Finf estimated from Figure 2 in study.
     . Finf presented in box plot (Figure 8), however data is difficult to deduce. No numeric values reported.
    December 2009
                                    A-349
    

    -------
    Table A-65.  Summary of PM - copollutant exposure studies.
    Reference PM metric Copollutant metric Association between PM and copollutant Primary findings
    Fruin et al. (2008, In-vehicle UFP, BC, PM- In-vehicle NOX, CO
    0971831 bound PAH
    Schwartz et al. (2007, Ambient and personal Ambient and personal 03
    0902201 PM2 .5 data from the and N02 data from the
    Baltimore panel study Baltimore panel study.
    Tolbert et al. (2007, Ambient PM10, PMi0-25, Ambient 03, N02, CO,
    0903161 PM25, EC, OC.TC, S042" S02
    , water-soluble metals,
    oxygenated
    hydrocarbons
    R
    UFP
    PM25
    NO
    BC
    CO
    C02
    UFP
    1
    
    
    
    
    
    PM,,
    071
    1
    
    
    
    
    NO
    0.97
    0.69
    1
    
    
    
    BC
    0.95
    0.89
    0.91
    1
    
    
    CO CO,
    0.63 0.72
    0.66 0.68
    0.78 0.85
    0.65 0.74
    1 0.94
    1
    \lote that these correlations are computed from data
    presented by Fruin et al. (2008, 0971831 for mean
    concentrations at different loc ations.
    Median p for regressions:
    
    Personal
    PM25
    Personal
    PM25of
    ambient origin
    Personal
    so/-
    Personal 03
    Personal N02
    Ambient Ambient 03
    PM25
    0.0143 -0.0016
    0.0183 -0.0037
    0.0051 0.0035
    0.0014 0.0010
    0.0015 0.0009
    Amb ent
    N02
    0.0115
    0.0124
    0.0006
    0.0009
    0.0010
    
    
    PM10
    03
    N02
    CO
    SO,
    PMc
    PM25
    SO/
    EC
    OC
    TC
    Metals
    OHC
    sor
    SO^
    EC
    OC
    TC
    Metals
    OHC
    PM10
    1.0
    0.6
    0.5
    0.5
    0.2
    07
    0.8
    07
    0.6
    07
    07
    07
    0.5
    EC
    1.0
    0.3
    0.3
    0.3
    07
    0.5
    03
    
    1.0
    0.4
    0.3
    0.2
    0.4
    0.6
    0.6
    0.4
    0.5
    0.5
    0.4
    0.4
    OC
    
    1.0
    0.8
    0.9
    0.5
    0.4
    N02
    
    
    1.0
    0.7
    0.4
    0.5
    0.6
    0.1
    0.6
    0.6
    0.7
    0.3
    0.2
    TC
    
    
    1.0
    1.0
    0.5
    0.4
    CO
    
    
    
    1.0
    0.3
    0.4
    0.4
    0.1
    0.7
    0.6
    0.6
    0.4
    0.3
    Metals
    
    
    
    1.0
    0.5
    0.4
    S02 PMc
    
    
    
    
    1.0
    0.2 1.0
    0.2 0.5
    0.1 0.3
    0.2 0.5
    0.2 0.5
    0.2 0.5
    0.1 0.5
    0.1 0.4
    OHC
    
    
    
    
    1.0
    0.5 1.0
    
    Brook et al. (2007, Anbient PM10, PM10-2 5, Ambient N02, NO Sn '^nrwi m^ nm '
    091153) PM25,S042-,andtrace ^100(100,100)
    metals in 10 Canadian KK&)
    PM10-2 5 0.31 (0.04, 0.50)
    PM,n 0.50 (0.23 0.70)
    S04 0.33(0.10, 0.48
    Fe 0.44 (0.29, 0.56)
    Zn 0.39 (0.28, 0.52)
    NiO.20 (0.06, 0.40)
    Mn 0.51 (0.37 0.62)
    As 0.21 (0.07, 0.39)
    AID. 07 (-0.1 7, 0.18)
    Cu 0.03 (-0.07 0.15)
    PbO.28 (0.16, 0.39)
    310.19(0.00,0.32)
    Se 0.1 4 (-0.04 0.35)
    Measurements of
    freeway UFP, BC, PM-
    bound PAH, and NO
    concentrations were
    roughly one order of
    magnitude higher than
    ambient
    measurements.
    Multiple regression
    analysis suggests
    these concentrations
    were a function of truck
    density and total truck
    count.
    Results suggest that
    ambient 03 exposure
    may be related to
    personal S042~
    exposure but not to
    personal PM25
    exposure on the whole.
    Ambient N02 exposure
    was associated with
    personal PM25
    exposure, possibly
    because both have
    traffic sources.
    
    
    
    PM consliluenls.
    uomponents were
    used in a multi-
    pollutant model to
    ^ oredict emeroencv
    
    
    
    07 lo be the mosl
    0.7 significant predictor ot
    0.5 cardiovascular disease
    visits in one-, two-, and
    
    
    
    
    lespiialuiy disease
    visits i none-, two-, and
    three-pollutant models.
    N02 showed the
    strongest association
    with mortality, but it is
    unclear if this
    association is due to
    health effects of N02 or
    health effects of
    copollutant PM.
    December 2009
    A-350
    

    -------
        Reference
          PM metric
      Copollutant metric
                 Association between PM and copollutant
      Primary findings
    Ito et al. (2007,
    1565941
    Ambient PM2
    Ambient 03, N02,
    CO
    S02,    Shown in figure format only.
    Authors tested
    relationship between
    meteorological
    variables and
    copollutants to
    determine if multi-
    pollutant models are
    impacted by spatial or
    temporal variation or by
    meteorological
    conditions.
    Multicollinearity varied
    by pollutant and
    Kauretal. (2005,
    0865041
    Fixed-site and personal
    PM25, personal UFP
    Fixed site and personal
    CO
            Personal R:
            PM25UFPCO
            PM2510.5 0.2
            UFPO.510.7
            CO 0.2 0.71
    Fairly low correlation
    was observed between
    PM25andCOand
    between PM25 and
    UFP, stronger
    correlations between
    UFP and CO.
    Kaur et al. (2005,      Fixed-site and personal    Fixed site and personal
    0881751             PM2 5 analyzed post-      CO
                        sample for light
                        absorbance (as indicator
                        for carbonaceous
                        aerosol), personal UFP
                                                  Personal R:
                                                  RPM25AbsCOUFP
                                                  PM2510.3-0.1 0.0
                                                  Abs  0.310.20.7
                                                  CO  -0.10.210.1
                                                  UFP  0.00.70.11
                                                                                Strongest correlation
                                                                                observed between UFP
                                                                                and absorption, which
                                                                                is reasonable given
                                                                                that much absorptive
                                                                                carbonaceous aerosol
                                                                                is in the ultrafine range.
    S0renson et al. Personal, indoor Personal, indoor
    (2005, 089428) residential, and outdoor residential, and outdoor
    residential PM25 and BC residential N02
    Sabin et al. (2005, BC, particle-bound PAH N02 on a school bus.
    087728) on a school bus.
    ^ersonal exposure regression coefficients to:
    
    Bedroom
    Front door
    Background
    
    
    BC
    PB-PAH
    N02
    PM,,
    072
    0.46
    0.29
    
    BC
    1
    
    
    BC
    0.47
    0.61
    0.03
    NO,
    0.70
    0.60
    0.56
    
    PB-PAH
    0.94
    1
    
    N02
    0.49
    0.37
    1
    Note that these correlations are computed from dat
    jresented by Sabin et al. for mean concentrations \
    est bus travelled behind different vehicles.
    Personal N02
    concentration is more
    strongly influenced by
    background than PM2 5
    orBC.
    Less correlation was
    observed between N02
    and PM species. This
    study was aimed more
    a, .. at fuel choices and
    when the control technologies for
    children's exposures on
    school buses.
    Lai et al. (2004,
    0568111
    Microenvironmental and
    personal PM25 and trace
    elements for personal
    exposure (P), residential
    indoor (Rl), residential
    outdoor (RO), and
    workplace (Wl)
    measurements.
    Microenvironmental and
    personal VOCs, N02, and
    CO.
    R(PM,,)
    TVOC
    N02
    CO
    P
    0.21
    -0.1
    -0.07
    Rl
    0.21
    -0.02
    NR
    RO
    0.41
    -0.16
    NR
    Wl
    -0.32
    0.09
    NR
    
    The EXPOLIS Oxford
    study was more
    focused on the indoor-
    outdoor exposure
    relationship, but the
    correlation results
    showed no important
    relationships between
    the pollutants shown.
    Gomez-Perales et al.   Microenvironmental PM25  Microenvironmental CO.   Ratio of Cone PM25 CO Benzene
    (2004, 054418: 2007,  with S04  , N0r, EC,
    1388161             OC.
                                                  Minibus/Bus 1.04 1.54 2.01
    
                                                   1.20 1.40 1.33
    
                                                  Minibus/Metro 1.70 2.02 3.20
    
                                                   1.433.033.10
                                                                                Morning and evening
                                                                                measurements of PM2 5
                                                                                were on avg higher and
                                                                                more variable than for
                                                                                benzene and CO (in
                                                                                order). Benzene and
                                                                                CO had higher and
                                                                                more variable
                                                                                concentrations for
                                                                                minibuses than for
                                                                                buses and metros,
                                                                                respectively, while
                                                                                PM25 concentrations
                                                                                were not substantially
                                                                                different for buses and
                                                                                minibuses.
    December  2009
                                                  A-351
    

    -------
        Reference
    PM metric
    Copollutant metric
    Association between PM and copollutant
    Primary findings
    Sarnat et al. (2001 , Fixed site and personal Ambient 03, N02, S02,
    019401) PM25 monitors. and CO
    R
    PM25
    03
    N02
    S02
    CO
    PM,,
    1
    -0.72
    075
    -0.17
    0.69
    0,
    0.67
    1
    -0.71
    0.41
    -0.67
    NO,
    0.37
    0.02
    1
    -0.17
    0.76
    SO,
    
    ...
    
    1
    -0.12
    CO
    0.15
    -0.06
    0.75
    -0.32
    1
    
    Strong association
    between ambient N02
    and personal PM25
    suggests that ambient
    gas may be a suitable
    surrogate for personal
    exposure.
    December 2009
                                       A-352
    

    -------
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                            Annex B.  Dosimetry
    B.1.   Ultrafine Disposition
    Table B-1.    Ultrafine disposition in humans.
     Reference  Study Group  Aerosol
    Study Protocol
    Observations
    Mills et
    al.(2006,
    0887701
    
    
    
    
    Holler etal.
    (2008,
    1567711
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Wiebert et al.
    (2006,
    1561541
    
    
    
    
    
    Wiebert et al.
    (2006,
    157146)
    
    
    
    
    
    
    Healthy
    nonsmokers
    (5 M, 5 F;
    21-24yr)
    
    
    
    Healthy
    nonsmokers
    
    (n = 9;
    50 ± 11 yr)
    QrYinkPrQ
    Ol I lUrvCI o
    /n - -in1
    V ' "l
    ^1 + 1D \ir}
    j i z iu yi i
    COPD patients
    (n - 7'
    ([!-/,
    RQ 4- 10 \/r\
    oy I iu y[j
    
    
    
    
    
    
    Subjects having
    varied health
    status (9M, 6F;
    46-74 yr)
    
    6 healthy
    5 asthmatic
    4 smokers
    Healthy
    subjects (4M,
    5F; 56 + 9 yr)
    Asthmatics (2M,
    3F; 59 + 6 yr)
    Pnntrnl M M1
    OUI ILIUI ^ 1 IVI,
    Łn wr\
    ou yi)
    
    Carbon -
    99mTc
    
    108nm
    CMD
    (08 = 2.2)
    Technegas
    Generator
    Carbon -
    99mTc
    
    ~100nm
    CMD
    Tprhnpn3Q
    icui M icyao
    Generator
    
    
    
    
    
    
    
    
    
    
    Carbon -
    99mTc
    
    87nmCMD
    (eg = 1.7)
    Tprhnpn3Q
    icui M icyao
    Qpnprgfor
    
    Carbon -
    99mTc
    34nmCMD
    (eg = 1.5)
    T h
    lecnnegas
    oenerator
    
    
    Lung activity in the lung was measured at 0, 1,
    and 6 h post aerosol inhalation.
    
    
    
    
    
    On two separate occasions, subjects inhaled
    100 ml aerosol boli to target front depths of
    150 and 800 ml into the lungs to target the
    airways and alveoli, respectively. Retention
    measured at 10min, 1.5, 5.5, 24 and 48 h
    post inhalation. Isotope (99mTc) leaching from
    particles assessed via filters in saline, blood,
    and urine. 81 mKr utilized to assess ventilation.
    
    
    
    
    
    
    
    
    
    
    Technegas system was modified to reduce
    leaching of 99mTc radiolabel from particles.
    The avg tidal volume during aerosol inhalation
    was 1.8 L (range 0.8-3.3). Activity in chest
    region measured at 0, 2, 24, 46, and 70 h after
    inhalation. Leaching assessed in vitro and via
    urine collection.
    
    Slow deep aerosol inhalations with 10s breath
    hold. Mean inhalation time of 6 min. Control
    subject inhaled aerosol with loosely bound
    radiolabel. Retention scans at 10 min, 60 min,
    100 min, and 24 h post inhalation. Leaching
    assessed in vitro and via collection of blood
    and urine.
    
    
    
    On avg, lung activity decreased 3.2 + 0.7% during the first h and
    1.2 + 1.7% over the next 5 h. With 95.6% of the particles in the lungs
    at 6 h post inhalation and no accumulation of radioactivity detected
    over the liver or spleen, findings did not support rapid translocation
    from the lungs into systemic circulation.
    
    
    Shallow airways boli-Total deposition in airways (shallow boli) similar
    between groups. Pattern of deposition was significantly more central
    in the healthy subjects which was thought due to non-uniform
    ventilation distribution in smokers and COPD patients as visualized
    by gamma-camera scans. Airway retention after 1.5 h was
    significantly lower in healthy subjects (89 + 6%) than smokers (97 +
    3%) or COPD patients (96 + 6%). At 24 and 48 h, retention
    significantly remained higher in COPD patients (86 + 6% and 82 +
    6%) than healthy subjects (75 + 10% and 70 + 9%).
    Deep alveolar boli - Total deposition in alveoli (deep boli) significantly
    greater in smokers (64 + 11%) and COPD patients (62 + 5%) than
    healthy subjects (50 + 8%). Alveolar retention of particles similar at all
    times between groups. For example, at 48 h, 97 + 3% in healthy
    subject, 96 + 3% in smokers, and 96 + 2% in COPD patients.
    Retention at 24 and 48 correlated with isotope leaching, suggesting
    that the small amount of clearance primarily reflected the
    disassociation of 99mTc from the particles with little transport of
    particles from the lungs.
    Lung function not significantly different between healthy and affected
    lungs. The aerosol deposition fraction was 41 + 10%. Lung retention
    was 99 + 3%, 99 + 5%, and 99 + 10% at 24, 46, and 70 h post
    inhalation. Cumulative in vitro leaching by 70 h was 2.6 + 0.96%.
    Except for radiotracer leaching from particles (1.0 + 0.6% of initially
    deposited activity in urine by 24 h), there was not significant
    clearance from the lungs by 70 h. Individual leaching was not
    correlated with individual retention.
    Avg deposition fraction of 60 + 17% which was correlated with tidal
    volume during aerosol inhalation (p = 0.01). Activity excreted in urine
    over 24-h post inhalation was 51 % in the control subject (high 99mTc
    disassociation) and 3.6 + 0.9% of deposited activity. In the blood of
    the control subject, activity was 30%, 31%, and 5% of the deposited
    activity at 20 min, 80 min, and 24-h (respectively), whereas it was
    only 0.9 + 0.6%, 1.1 + 0.4%, and 1.5 + 0.5% the other 13 subjects at
    these times. Lung retention in the control subject was 30% at 1-h and
    18%at24h. In the remainder of subjects, lung retention was
    approximately 100% through 24 h.
     Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
     Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
     developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
    December 2009
              B-1
    

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    Table  B- 2.     Ultrafine disposition  in animals.
     Reference   Study Group
                           Aerosol
                                 Study Protocol
                                                             Observations
    Bermudez et
    al.(2004,
    0567071
    Fischer 344 rats,
    females (6 wk)
    
    B3C3F1 mice,
    females (6 wk)
    
    Hamsters,
    females (6 wk)
    Ti02:1.29-1.44pm
    MMAD
    (og = 2.46-3.65), 21
    nm primary particles
    Animals exposed 6 h/day, 5 day/wk,
    foMSwk to 0.5, 2and10mg/m3.
    Control animals exposed to filtered
    air. Animals sacrificed at 0, 4,13,
    26, and 56 (49 for hamsters) post-
    exposure. Groups of 25 animals per
    species and time point.
    Ti02 pulmonary retention half-times for the low-, mid-, and high-
    exposure groups, respectively: 63,132, and 365 days in rats; 48, 40,
    and 319 days in mice; and 33, 37, and 39 days in hamsters.
    
    Burden of Ti02 in lymph nodes increase with time postexposure in
    mid- and high-dosed rats; in high-dosed mice; but was unaffected in
    hamsters at any time or dosage group. In high-exposure groups of
    mice, epithelial permeability remained elevated (~2x control groups)
    out to 52 wk without signs of recovery. Epithelial permeability was
    3-4* control in high exposed rats through 4 wk post exposure, but
    approached control by 13 wk. Epithelial permeability was unaffected
    in all groups of hamsters.
    Chen et al.
    (2006,
    0879471
    Sprague-Dawley
    male rats
    
    (220 ± 20 g)
    Polystyrene
    
    1251 radiolabel
    
    Ultrafine: 56.4 nm
    
    Fine: 202 nm
    Intratracheal instillation of particles
    in healthy rats or those pretreated
    with IPS (12 h before particle
    instillation). Healthy rats sacrificed
    between 0.5-2 h and at 24 or 48 h
    post-instillation. IPS treated rats
    were sacrificed 0.5-2 h
    post-instillation.
    In healthy rats, there were no marked differences in lung retention or
    systemic distribution between the Ultrafine and fine particles. Results
    for healthy animals focused on Ultrafine particles which were
    primarily retained in lungs (72 + 10% at 0.5-2 h; 65 + 1% at 1 day;
    62 ± 5% at 5 days). Initially, there was rapid particle movement into
    the blood (2 ± 1% at 0.5-2 h; 0.1 ± 0.1% at 5 days) and liver (3 ± 2%
    at 0.5-2 h; 1 + 0.1% at 5 days). At 1 day post-instillation, about 13%
    of the particles where in the urine or feces. Following IPS treatment,
    Ultrafine accessed the blood (5 vs. 2%) and liver (11 vs.  4%) to a
    significantly greater extent than fine particles.
    Geiser et al.    Wistar rats 20
    (2005,         adult males
    0873621
    	        (250+10 g)
    Also included
    in in vitro
    studies
                     Ti02 (22 nm CMD,
                     1.7 og)
    
                     Spark generated
    
                     0.11 mg/m3
    
                     7.3x106
                     particles/cm3
                        Rats exposed 1-h via endotracheal
                        tube while anesthetized and
                        ventilated at constant rate. Lungs
                        fixed at 1 or 24-h postexposure.
                                      Distributions of particles among lung compartments followed the
                                      volume distribution of compartments and did not differ significantly
                                      between 1 and 24-h post-inhalation. On avg, 79.3 + 7.6% of
                                      particles were on the luminal side of the airway surfaces, 4.6 + 2.6%
                                      in epithelial or endothelial cells, 4.8 + 4.5% in connective tissues,
                                      and 11.3 + 3.9% within capillaries. Particles within cells were not
                                      membrane-bound.
    Kapp et al.
    (2004,
    1566241
    Charles River
    rats
    
    5 young adult
    male
    
    (250+10 g)
    Ti02 (22 nm CMD,
    1.7 og)
    
    Spark generated
    Rats exposed 1-h via endotracheal
    tube while anesthetized and
    ventilated at constant rate. Lungs
    fixed immediately postexposure.
    Of particles in tissues, 72% were aggregates of 2 or more particles;
    93% of aggregates were in round or oval shape aggregates, 7%
    were needle-like. The size distribution of particles in lung tissues (29
    nm CMD, 1.7 og) was remarkably similar to the aerosol; the small
    discrepancy may have been due to differences sizing techniques. A
    large 350 nm aggregate was found in a type II pneumocyte, a 37 nm
    particle in a capillary close to the endothelial cells, and a 106 nm
    particle within the surface-lining layer close to the alveolar
    epithelium.
    December 2009
                                                             B-2
    

    -------
    Table B- 3.     In vitro studies of ultrafine disposition.
     Reference
                      Animal
                                         Particles
                                                                  Study Protocol
                                                                                                               Observations
    Edetsberger   Human cervix
    et al. (2005,   carcinoma cells
    1557591      (HeLa cells)
                       Polystyrene spheres
                       (0.020 urn)
                          Cells incubated with polystyrene particles
                          having negative surface charges. Cell
                          cultures were naive or treated with
                          Genistein or Cytochalasin B (CytB) prior
                          to particle application. Genistein inhibits
                          endocytotic processes,  expecially
                          caveolae internalization. CytB inhibits
                          actin polymerization and phagocytosis.
    Particles translocated into cells by first measurement (~1 min
    after particle application) independent of treatment group. In
    naive cells, agglomerates of 88-117 nm were seen by 15-20
    min and of 253-675 nm by 50-60 min after particle
    application. Intracellular aggregates thought to be result from
    particle incorporation into endosomes or similar structures. In
    treated cells, onlya small number of agglomerates (161-308
    nm) were found and only by 50-60 min. At 50-60 min, 90%
    and 98% of particles were in the 20-40 nm range in naive and
    treated cells, respectively. Particles did  not translocate into
    dead cells, rather they attached to outside of the cell
    membrane.
    Geiser et al.   Porcine lung
    (2005,        macrophages(106
    0873621      cell/mLuman red
                 blood cells (RBC; 8
    Also included  x i06cells/mL)
    inhalation
    study
                       Fluorescent
                       polystyrene spheres
                       (0.078, 0.2, and
                       1pm)
    
                       Gold shheres
    
                       (0.025 urn)
                          Cells cultured for 4 h with each sized
                          polystyrene spheres. RBC were
                          employed as a model of nonphagocytic
                          cells. Some macrophages cultures were
                          treated with cytochalasin D (cytD) to
                          inhibit phagocytosis.  In addition, RBC
                          were also cultured with gold particles.
    Of the non-cytD treated macrophages, 77 + 15%, 21 + 11%,
    and 56 + 30% contained 0.078, 0.2, and 1 pm particles,
    respectively. CytD treatment of macrophages effectively
    blocked the phagocytosis of 1 pm particles, but did not alter
    the uptake of the 0.078 and 0.2 pm particles. Human RBC
    were found to contain 0.078 and 0.2 pm polystyrene spheres
    as well as the 0.025 pm gold particles, which were not
    membrane bound. In contrast, the RBC did not contain the
    larger 1 pm polystyrene spheres. Results suggest that
    ultrafine and fine (0.078 and 0.2 pm diameter) particles cross
    cellular membranes by a non-endocytic (i.e. not involving
    vesicle formation) mechanisms such as adhesive interactions
    and diffusion.
    Geys et al.
    (2006,
    1557891
     Human alveolar
     (A549) and
     bronchial (Calu-3)
     epithelial cellsRat
     primary type II
     pneumocytes
    Amine- and
    carboxyl-modified
    fluorescent
    polystyrene (46 nm)
                          Cells cultured in clear polyester
                          transwells with 0.4 or 3 pm pores.
                          Monolayer considered "tight" when <1%
                          sodium fluorescein moved from apical to
                          basolateral compartment. Particle
                          translocation assessed in transwells with
                          and without cells. Cells incubated with
                          particles for 14-16 h to assess
                          translocation from apical to basolateral
                          compartment.
    Without cells, 13.5% of carboxyl-modified particles passed
    through the 0.4 pm pores (n = 7) and 67.5% through 3 pm
    pores (n = 3). Movement of the amine-modified particles was
    4.2% through 0.4 pm pores (n = 7) and 52.7% through 3 pm
    pores (n = 3). The integrity of the monolayerwas insufficient
    for translocation studies using the A549 cells (0.4 and 4 pm
    pore size) and rat pneumocytes (0.3 pm  pore). Using 0.4 pm
    pores, there was no detectable translocation through either
    Calu-3 or rat pneumocyte monolayers. Using 3 pm pores,
    ~6% of both particle types passed through the Calu-3
    monolayer; however, results were highly variable with no
    translocation in 2 (of 5) and 3 (of 6) trials with carboxyl- or
    amine-modified particles, respectively.
    B.2.    Olfactory  Translocation
    Table B-4.      Olfactory particle translocation.
    Reference  Study Group
                           Aerosol
                                    Study Protocol
                       Observations
    DeLorenzo  Squirrel
    (1970,
    156391)
    monkeys
    
    Young males
    
    (1kg)
    Silver-coated colloidal    Intranasal instillation of 1 mL particle
    gold (50 nm)            suspension. Animals sacrificed at 0.25,
                           0.5,1, and 24-h after instillation.
     Rapid movement (30-60 min) into olfactory bulbs. Within
     30 min of being placed on nasal mucosa, particle
     aggregates were seen in axoplasm of the fila olfactoria
     Within 1  h, particles were in olfactory glomerulus.
     Particles in the olfactory bulb were located preferentially
     in mitochondria and not free in the cytoplasm.
    Dormanet   Crl:CDrats
    al  (2001
    055433)     Males (6 wk old)
                     Soluble and insoluble
                     Mn particle types;
    
                     MMAD= 1.3-2.1 urn;
                     GSD<2
                          Whole body exposure (6 h/day, 14
                          consecutive days) to 0, 0.03, 0.3, and
                          3 mg Mn/m  . Tissues analyzed in six
                          animals per concentration exposed to
                          soluble (MnS04) or insoluble (Mn304)
                          aerosols.
     Increased Mn levels in olfactory bulb observed following
     MnS04 of > 0.3 mg Mn/m3 and following Mn304 of 3 mg
     Mn/m . At 3 mg Mn/m , Mn levels were significantly
     greater in olfactory bulb (1.4-fold) and striatum (2.7-fold)
     following soluble Mn04 than insoluble Mn304. Mn levels
     in the cerebellum were unaffected following all
     exposures.
    December 2009
                                                            B-3
    

    -------
    Reference
    Dorman et
    al. (2004,
    155752)
    Elder etal.
    (2006,
    089253)
    Oberdb'rster
    etal. (2004,
    055639)
    Persson et
    al. (2003,
    051846)
    Study Group
    Crl:CD rats
    Males (6 wk old)
    Fisher 344 rats
    Males
    (200-250 g)
    Fisher 344 rats
    Males(14wk;
    284 ± 9 g)
    Sprague-Dawley
    male rats (150g)
    Freshwater Pike
    female (3 kg)
    Aerosol
    Soluble and insoluble
    Mn particle types;
    MMAD= 1.5-2 urn;
    GSD=1.4-1.6
    Mn oxide (~30 nm
    equivalent sphere with
    3-8 nm primary
    particles)
    Spark generated
    0.5 mg/m3
    18 x 106 particles/cm3
    13C(36nmCMD, 1.7
    °g)
    Spark generated
    65ZnCI2 dissolved in
    0.1 M HCI
    Study Protocol
    Whole body exposure (6 h/day,
    5 days/wk, 13 wk) to MnS04 at 0, 0.01 ,
    0.1 , and 0.5 mg Mn/m3. Compared to
    Mn phosphate (as hureaulite)
    exposure of 0.1 mg Mn/m3. Brain Mn
    levels assessed immediately following
    90 days of exposure or 45 days
    postexposure.
    Whole body inhalation exposure to
    either filtered air or Mn oxide for 1 2
    days (6 h/day, 5 days/wk) with both
    nares open or Mn oxide for 2 days (6
    h/day) with right nostril blocked.
    Intranasal instillation in left nostril of
    Mn oxide particles or soluble MnCI2
    suspended in 30 uL saline. Analyzed
    Mn in the lung, liver, olfactory bulb, and
    other brain regions.
    Rats (n = 12 3 per time point) exposed
    to 1 60 ug/m for 6 h in whole-body
    chamber and sacrificed at 1 , 3, 5, and
    7 day postexposure. Lung, olfactory
    bulb, cerebrum, and cerebellum
    removed for 13C analysis. Tissue
    ISC-levels were determined by isotope
    ratio mass spectroscopy and
    background corrected for 13C levels in
    unexposed controls (n = 3).
    Rats: intransal (0.03 pg Zn in 10 pL) or
    intraperitoneally (0.03 pg Zn in 100 pL);
    autoradiography and y spec at 1 day or
    1, 3, or 6 wk postexposure.
    Pike: instilled (0.1 2 pgZn in 10|jL)in
    right or both olfactory chambers, assayed
    2wk postexposure
    Observations
    Relative to air, the insoluble hureaulite was significantly
    increased at 90 days of exposure in the olfactory bulb,
    but not striatum or cerebellum. The soluble Mn
    phosphate showed a dose dependent increase in
    olfactory bulb Mn levels at 90 days. At 0.1 mg Mn/m3, Mn
    levels following Mn phosphate were significantly
    increased in the olfactory bulb and striatum relative to
    hureaulite and air exposures. At 45 days postexposure,
    relative to air, olfactory bulb Mn levels only remained
    increased Mn phosphate group at 0.5 mg Mn/m .
    After 12 day exposure via both nostrils, Mn in the
    olfactory bulb increased 3.5-fold, whereas in the lung Mn
    concentrations doubled; there were also increases in the
    striatum, frontal cortex, and cerebellum. After the 2 days
    exposure with the right nostril blocked, Mn accumulated
    in the mainly in the left olfactory bulb (~2.4-fold increase)
    in to a lesser extent in the right olfactory bulb (1 .2-fold
    increase). At 24-h post instillation, the left olfactory bulb
    contained similar amounts of the poorly soluble Mn oxide
    (8.2 ± 0.7%) and soluble MnCI2 (8.2 ± 3.6%) as a
    percent of the amount instilled.
    At 1 day postexposure, the lungs of rats exposed to ultrafme
    13C particles contained 1.34 + 0.22 pgof 13C
    (1.39 pg/g-lung) following background corrected. By 7 days
    postexposure, the 13C concentration had decreased to
    0.59 ug/g-lung. There was a significant and persistent
    increase in 13C in the olfactory bulb of 0.35 pg/g on day 1,
    which increased to 0.43 pg/g by day 7. Day 1 concentrations
    of 13C in the cerebrum and cerebellum were also
    significantly increased but the increase was inconsistent,
    possibly reflecting translocation of particles from the blood
    across the blood-brain barrier into brain regions.
    Zn uptake in olfactory epithelium and transport along
    olfactory neurons to olfactory bulb. Zn continued into
    interior of olfactory bulb and in rat went into anterior
    olfactory cortex. Zn found bound to both cellular
    constituents and cytosolic components. Some Zn bound
    to metallothionein in olfactory mucosa and olfactory bulb.
    Wang et al.  CD-1 (ICR) mice  Rutile Ti02
    (2007,
    155147)                      21 and 80 nm
    
                                 Anatase Ti02155 nm
                                           Twenty mice (n = 5 per group)
                                           exposed 0 or 0.01 g-Ti02 per mL Dl.
                                           Instilled 25 uL each day for 5 days,
                                           then inhaled 10 uL every other day.
                                           Mice sacrificed after 1 mo.
                                                                                           Rutile particles were observed to be column/fiber
                                                                                           shaped, whereas anatase was octahedral. Ti02 particles
                                                                                           taken up by olfactory bulb via the olfactory nerve layer,
                                                                                           olfactory ventricle, and granular  cell layer of the olfactory
                                                                                           bulb. Fine Ti02 showed greater entry into the olfactory
                                                                                           bulb presumably due to aggregation of smaller rutile
                                                                                           particles that was not seen for the fine anatase particles.
    Yu et al.
    (2003,
    Sprague-Dawley
    male rats, 6 wk
                                 Stainless steel
                                 welding-fume
    
                                 «,5um
    Whole body exposure 2 h/day for 1,
    15, 30, or 60 days
    
    Low: 64 ± 4 mg/m3 (1.6 mg/m3 Mn)
    
    High: 107 ± 6 mg/m3 (3.5 mg/m3 Mn)
    Significant increases in cerebellum Mn at 15-30 days of
    exposure.
    
    Slight increases in Mn in substantia nigra, basal ganglia,
    temporal cortex, and frontal cortex after 60 days.
    Significant increase at 30 days in basal ganglia at low
    dose. Authors suggested that pharmacokinetics and
    distribution of welding fume Mn differs from pure Mn.
    December 2009
                                                           B-4
    

    -------
    B.3.   Clearance and  Age
    Table B-5.      Studies of respiratory tract mucosal and macrophage clearance as a function of age.
     Reference   Animal
                         Particles
                                               Study Protocol
                                                      Observed Effect(s)
    NASAL AND TRACHEAL CLEARANCE
    Hoetal.      Human,    Not applicable
    (2001,        males and
    156549)      females
                                            Ninety subjects (47 M, 43 F; 52 ± 23 yr)
                                            between 11 and 90 yr of age were recruited
                                            to measure nasal saccharine clearance and
                                            ciliary beat frequency.
                                                                          Ciliary beat frequency (n = 90; r = -0.48, p
                                                                          <0.0001) and nasal mucociliary clearance time
                                                                          (n = 43; r = 0.64, p O.001) were correlated with
                                                                          subject age. Nasal clearance times were
                                                                          significantly (p <0.001) faster in individuals
                                                                          under 40 yr of age (9.3 + 5.2 min) versus older
                                                                          subjects (15.4 + 5.0 min). Results similar
                                                                          between males and females.
    Goodman et   Humans,   Radiolabed Teflon disks (1 mm
    al. (1978,     males and  diameter, 0.8 mm thick)
    071130)      females
                                            Tracheal mucus velocity following delivery via
                                            bronchoscope to the tracheal mucosa. Ten
                                            young (2 M, 8 F; 23 ± 3 yr) and ten elderly (2
                                            M, 5 F; 63 ± 5 yr) nonsmokers served as
                                            control subjects. Measurements were also
                                            made in young smokers, ex-smokers, and
                                            individuals with chronic bronchitis.
                                                                          Young nonsmokers had a tracheal mucus
                                                                          velocity of 10.1 ±3.5 mm/min which was
                                                                          significantly faster than the velocity of
                                                                          5.8 ± 2.6 observed in the elderly
                                                                          nonsmokers.
    Whaley et al.  Beagle    Macroaggregated albumin99mTc
    (1987,        dogs,      labelled
    156153)      males and
                 females
                                            Intratracheal instillation of 10- pi droplet of
                                            labelled albumin in saline. Tracheal clearance
                                            followed 25 min. Longitudinal measure
                                            measurements in 5 males and 3 females when
                                            young adults (2.8-3 yr), middle-aged (6.7-6.9 yr),
                                            and mature (9.6-9.8 yr). Additional 5 females
                                            and 3 males comprised immature group (9-10
                                            mo) and 4 males and 4 females used as aged
                                            group (13-16 yr).
                                                                          Tracheal mucus velocity significantly
                                                                          (p <0.05) greater in young (9.7 ± 0.6 [SE]
                                                                          mm/min) and middle-aged (6.9 ± 0.5) groups
                                                                          than in immature (3.6 ± 0.4), mature
                                                                          (3.5 ± 0.8), and aged (2.9 ± 0.5) dogs.
    Yeates et al.   Humans,   Radioaerosols 99mTc labelled
    (1981,        males and
    095391)      females
                                            Tracheal mucus velocities compiled for 74
                                            healthy non-smoking subjects (60 M, 14 F;
                                            10-65 yr, mean 30 yr) from prior studies.
                                            Forty-two (32 M, 10 F) inhaled albumin in
                                            saline droplets (6.2-6.5 urn MMAD), Yeates et
                                            al. (1975); twenty-two (21  M, 1 F) inhaled  iron
                                            oxide (4.2 urn MMAD), Yeates et al. (1981 b);
                                            and ten (7 M, 3 F) inhaled monodisperse iron
                                            oxide aerosol (7.5 urn MMAD), Leikauf et  al.
                                            (1981). Inhalations were via a mouthpiece
                                            with an inspiratory flow of ~1 liter/sec.
                                                                          Alognormal distribution of tracheal mucus
                                                                          velocities was reported. Age did not appear
                                                                          to affect velocities, e.g., 4.7 ± 2.5 mm/min in
                                                                          18-24yr olds vs. 4.6 ± 3.2 mm/min in
                                                                          individuals >30 yr of age. However, it should
                                                                          be noted that only 2 subjects were greater
                                                                          than 45 yr of age and that the data was
                                                                          complied from three studies using differing
                                                                          experimental techniques. Rather similar
                                                                          tracheal mucus velocities in males (4.7 ± 3.0
                                                                          mm/min) and females (4.9 ± 2.4 mm/min).
    BRONCHI AND BRONCHIOLES CLEARANCE
    Puchelle et
    al. (1979,
    006863)
    Human,
    males
    7.4 urn MMAD99mTc labelled
    resin
    Mucociliary clearance measured for 1 h post
    aerosol inhalation in 19 healthy non-smoking
    males (21-69yrof age). Clearance measure
    on two occasions in 16 individuals.
    Negative correlation (r = -0.472, p <0.05)
    between mucociliary clearance and age.
    Younger subjects (n = 9;21-37yr) had1-h
    clearance of 34 ± 14% which was
    significantly greater than the 22 ± 8% found
    in the older subjects (n = 5;>54yr).
    Separated by 5.4 wk (on avg), there was a
    good correlation between repeated
    clearance measurements (r= 0.65, p
    <0.001)
    Svartengren   Humans,   6 urn MMAD111 In labelled Teflon
    etal.(2005,   males and
    157034)      females
                                            Small airway clearance measured in five age
                                            groups (< 24 yr, n = 13; 25-29 yr, n = 8;
                                            30-49yr, n = 7; 50-64, n = 9; >65 yr, n = 9) of
                                            healthy subjects. Aerosol inhaled via
                                            mouthpiece at extremely slow rate of 0.05
                                            L/s. Activity in lungs measured at 1 day, 2
                                            days, and 1, 2, and 3 wk post-exposure.
                                            Under the presumption that most large  airway
                                            clearance was complete by 24 h, retention at
                                            24 h was normalized to 100%.
                                                                          Large and small airway clearance slowed
                                                                          with increasing age. Clearance correlated
                                                                          with age at all times (r = -0.46 to -0.50, -0.55,
                                                                          -0.66, and -0.70 at 1 day, 2 days, 1 wk, 2 wk,
                                                                          and 3 wk, respectively).  Based on linear
                                                                          regression, the clearance from 1 to 21 days
                                                                          post-exposure was 47% in a 20 yr-old
                                                                          versus 23% in an 80 yr-old.  Lung function
                                                                          was not a significant predictor of clearance
                                                                          when age considered.
    December 2009
                                                       B-5
    

    -------
     Reference   Animal
    Particles
    Study Protocol
    Observed Effect(s)
    Vastag et al.  Humans,   Monodisperseerythrocytes99mTc
    (1985,        males and  labelled
    157088)      females
                        Clearance measured for 1-h post-inhalation
                        in eighty healthy (59 M, 21  F; 43 ± 17 yr)
                        subjects who had never smoked. Smokers
                        and ex-smokers also studied. Aerosol
                        inhalation not described.
                                Clearance significantly associated with age.
                                Based on linear regression, total mucociliary
                                clearance at 1-h post-exposure was 46% in
                                a 20 yr old versus 23% in an 80 yr old.
                                Similar results for males and females.
    ALVEOLAR CLEARANCE
    Muhle et al.   Fischer    3.5 urn MMAD 85Sr labelled
    (1990,        344 rats   polystyrene latex
    006853)
                        Control animals compared across several     Typical alveolar clearance half-time of 45
                        studies. Aerosol inhaled by short-term nose    days in 5-mo-old rats compared to 74 days
                        only exposure. Alveolar clearance determined  in 23-mo-old rats. Statistical significance of
                        by exponential fit to thoracic activity          findings not proved.
                        measured over 75-100 days excluding the
                        first 15 days post-exposure.
    December 2009
                                   B-6
    

    -------
                                       Annex  B References
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           (2005). Ultrafine particles cross cellular membranes by nonphagocytic mechanisms in lungs and in cultured cells.
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           analysis of inhaled ultrafine particles in rat lungs. Microsc Res Tech, 63: 298-305. 156624
    
    Mills NL; Amin N;  Robinson SD; Anand A; Davies J; Patel D; de la Fuente JM; Cassee FR; Boon NA; Macnee W; Millar
           AM; Donaldson K; Newby DE. (2006). Do inhaled carbon nanoparticles translocate directly into the circulation in
           humans?. Am J Respir Crit Care Med, 173: 426-431. 088770
    
    Moller W; Felten K; Sommerer K; Scheuch G; Meyer G; Meyer P; Haussinger K; Kreyling WG (2008). Deposition,
           retention, and translocation of ultrafine particles from the central airways and lung periphery. Am J Respir Crit Care
           Med, 177: 426-432. 156771
    
    Muhle H; Creutzenberg O; BellmannB; HeinrichU; Mermelstein R. (1990). Dust overloading of lungs: investigations of
           various materials, species differences, and irreversibility of effects. J Aerosol Med, 1: S111-S128. 006853
    
    Oberdorster G; Sharp Z; Atudorei V; Elder A; Gelein R; Kreyling W; Cox C. (2004). Translocation of inhaled ultrafine
           particles to the brain. Inhal Toxicol, 16: 437-445. 055639
     Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
     Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
     developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
    December 2009                                        B-7
    

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    Persson E; Henriksson J; Tallkvist J; Rouleau C; Tjalve H. (2003). Transport and subcellular distribution of intranasally
           administered zinc in the olfactory system of rats and pikes. Toxicology, 191: 97-108. 051846
    
    Puchelle E; Zahm J-M; Bertrand A. (1979). Influence of age on bronchial mucociliary transport. Scand J Respir Dis, 60:
           307-313.006863
    
    Svartengren M; Falk R; Philipson K. (2005). Long-term clearance from small airways decreases with age. Eur Respir J, 26:
           609-615.  157034
    
    Vastag E; Matthys H; Kohler D; Gronbeck L; Daikeler G. (1985). Mucociliary clearance and airways obstruction in
           smokers,  ex-smokers and normal subjects who never smoked. Eur J Respir Dis, 139: 93-100. 157088
    
    Wang C. (2007).  Impact of direct radiative forcing of black carbon aerosols on tropical convective precipitation. Geophys
           Res Lett,  34: 5709. 156147
    
    Whaley SL; Muggenburg BA; Seiler FA; Wolff RK. (1987). Effect of aging on tracheal mucociliary clearance in beagle
           dogs. JApplPhysiol,62:  1331-1334. 156153
    
    Wiebert P; Sanchez-Crespo A; Falk R; Philipson K; Lundin A; Larsson S; Moller W; Kreyling W; Svartengren M. (2006).
           No Significant  Translocation of Inhaled 35-nm Carbon Particles to the Circulation in Humans.  Inhal Toxicol, 18:
           741-747.  156154
    
    Wiebert P; Sanchez-Crespo A; Seitz J; Falk R; Philipson K; Kreyling WG; Moller W; Sommerer K; Larsson S; Svartengren
           M. (2006). Negligible clearance of ultrafine particles retained in healthy and affected human lungs. Eur Respir J,
           28: 286-290. 157146
    
    YeatesDB; Gerrity  TR; Garrard CS. (1981). Particle deposition and clearance in the bronchial tree. Ann BiomedEng, 9:
           577-592.  095391
    
    Yu IJ; Park JD; Park ES; Song KS; Han KT; Han JH; Chung YH; Choi BS; Chung KH; Cho MH. (2003). Manganese
           distribution in brains of Sprague-Dawley rats after 60 days of stainless steel welding-fume exposure.
           Neurotoxicology, 24: 777-785. 156171
    December 2009                                        B-8
    

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                                                   Annex  C.
           Controlled  Human   Exposure  Studies
    Table C-1.    Cardiovascular effects.
             Study
           Pollutant
                  Exposure
                   Findings
    Reference: Barregard et al.  Wood smoke
    (2006, 091381)
                            Particle Size:
    Subjects: 13 healthy adults  Session 1: GMD 42 nm;
    Gender: 6 M/7 F
    
    Age: 20-56 yr
    Session 2: GMD 112 nm
    
    Particle Number/Count:
    Session 1:180,000/cm3;
    Session 2:95,000/cm3
    
    Concentration:
    Session 1: median:
    279 ug/m3;
    Session 2: median
    243 ug/m3
    Subjects exposed in two groups for 4 h to
    filtered air, followed a wk later by a 4-h
    exposure to wood smoke. Exposures
    conducted with two 25-min periods of light
    exercise. Other measured combustion
    products:
    
    Session 1: N02 (0.08 ppm), CO (13 ppm),
    formaldehyde (114 ug/m3), acetaldehyde
    (75 ug/m ), benzene (30 ug/m ),
    1,3-butadiene (6.3 ug/m3);
    
    Session 2: N02 (0.09 ppm), CO (9.1  ppm),
    formaldehyde (64 ug/nv), acetaldehyde
    (40 ug/m3), benzene (20 ug/m3),
    1,3-butadiene (3.9 ug/m3).
    
    Time to analysis: Immediately following
    exposure as well as 3 and 20 h post-
    exposure.
    Statistically significant increase in plasma
    factor VIII 20 h post wood smoke exposure
    relative to filtered air. The factor Vlll/von
    Willebrand ratio in plasma was increased with
    wood smoke relative to filtered air at 0, 3, and
    20 h post-exposure. Wood smoke exposure
    increased the urinary excretion of free
    8-iso-prostaglandin2a relative to clean air 20 h
    post-exposure (n = 9). These findings were
    more pronounced in session 1 than session 2
    (similar mass concentration but higher number
    concentration in Session 1).
    Reference: Beckett et al.    Ultrafine and fine zinc oxide
    (2005,156261)
    v	            Particle Size: UF:
    Subjects: 12 healthy adults  <0.1 urn; Fine: 0.1-1.0 urn
    
    Gender: 6 M/6 F
    
    Age: 23-52 yr
    Particle Number/Count:
    UF: 4.6 xio7/cm3; Fine: 1.9
    x105/cm3
    
    Concentration: 500 ug/m3
    Subjects exposed via mouthpiece for 2 h
    during rest to filtered air, ultrafine, and fine
    zinc oxide in a randomized crossover study
    design. Exposures were separated by at least
    3wk.
    
    Time to analysis: Immediately following
    exposure and 3, 6,11,23, and 24 h after
    exposure.
    Exposure to ultrafine and fine zinc oxide did
    not affect HRV (time and frequency domain
    parameters) relative to clean air immediately
    following exposure, or at 3, 6,11, and 23 h
    post-exposure. Exposure did not affect blood
    pressure through 24 h post-exposure. No
    effects of exposure to either fine or ultrafine
    zinc oxide observed on factor VII, von
    Willebrand factor (vWf), tissue plasminogen
    activator (t-PA), or fibrinogen. No effect of
    exposure observed on peripheral blood cell
    counts or levels of pro-inflammatory cytokines.
    Reference: Blomberg et al.   DE
    (2005,191991)
    
    Subjects: 15 older adults
    (former smokers) with COPD
    
    Age: 56-72 yr
    Concentration: 300 ug/m3
    Subjects exposed for 1 h with intermittent      DE was not observed to affect blood levels of
    exercise to DE and filtered air in a randomized  C-reactive protein, fibrinogen, D-Dimer,
    crossover study design.                    prothrombin factor 1-2, or von Willebrand
                                          factor activity at 6 and 24 h post-exposure.
    Time to analysis: 6 and 24 h post-exposure.
    Reference: Brauner et al.
    (2007, 091152)
    
    Subjects: 29 healthy adults
    
    Gender: 20 M/9 F
    
    Age: 20-40 yr
    Urban traffic particles
    Particle Number/Count:
    6-700nm:10,067/cm3
    
    Concentration: PIvl;:
    9.7 pg/m3; PMio-25-
    12.6|jg/m3
    Subjects exposed to urban traffic particles and
    filtered air for 24 h with and without two
    90-min periods of light exercise in a
    randomized crossover study design.
    Concentrations of NOX and NO were low and
    did not differ between filtered and unfiltered
    exposures. CO concentrations were higher
    with filtered air (0.35 and 0.41 ppm), while 03
    concentrations were lower with filtered air
    (12.08 and 4.29 ppb).
    
    Time to analysis: 6 and 24 h after the start of
    exposure.
    An increase in DNA strand breaks and
    formamidopyrimidine-DNAglycosylase sites in
    peripheral blood mononuclear cells were
    observed after 6 and 24 h of exposure to urban
    particulates. The particle concentration at the
    57nm mode was shown to be the major
    contributor to these effects.
     Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
     Environmental Research Online) at http://epa.gov/hero.  HERO is a database of scientific literature used by U.S. EPA in the process of
     developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
    December 2009
                                       C-1
    

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              Study
            Pollutant
                                              Exposure
                     Findings
    Reference: Brauner et al.
    (2008,156293)
    
    Subjects: 42 healthy older
    adults (21 couples)
    
    Age: 60-75 yr
    Indoor air particles
    
    Particle Number/Count:
    10-700 nm:10,016/cm3
    
    Concentration: Coarse:
    9.4 ug/m3; Fine: 12.6 ug/m3
                              Exposures consisted of two 48 h periods in
                              the home of each subject with or without the
                              use of a HEPAfilter (randomized crossover
                              design). HEPA filters reduced coarse
                              concentration from 9.4 to 4.6 ug/m3, and fine
                              concentration from 12.6 to 4.7 ug/m3.
                              Concentrations of N02 did not differ between
                              the 2 sessions (20 ppb).
    
                              Time to analysis: After the completion of
                              each 48 h session.
    The use of HEPA filters significantly improved
    microvascular function (p = 0.04) after 48 h
    (reactive hyperemia-peripheral arterial
    tonometry). Microvascular function was
    assessed using a scoring system representing
    the extent of reactive hyperemia. The
    reduction in PM concentration through the use
    of HEPA filters did not significantly affect blood
    pressure following the 48-h exposures.
    Lowering PM concentration did not significantly
    affect inflammatory response markers in
    peripheral venous blood (IL-6,TNF-a,
    C-reactive protein, plasma amyloid A).
    Reference: Brauner et al.
    (2008,191966)
    
    Subjects: 29 healthy adults
    
    Gender: 20 M, 9 F
    
    Age: M avg 27 yr, F avg
    26 yr
    Urban traffic particles
    
    Particle Number/Count:
    11,600/cm3
    
    Concentration: PM25:
    10.5|jg/m3;PMio.25:
    13.8|jg/m3
                              Subjects exposed to urban traffic particles and
                              filtered air for 24 h with and without two
                              90-min periods of light exercise in a
                              randomized crossover study design.
                              Concentrations of NOX and NO were low and
                              did not differ between filtered and unfiltered
                              exposures. CO concentrations were higher
                              with filtered air, while 03 concentrations were
                              lower with filtered air.
    
                              Time to analysis: 6 and 24 h after the start of
                              exposure.
    Exposure to urban traffic particles was not
    observed to affect microvascular function
    (digital peripheral artery tone) at 6 or 24 h after
    the start of exposure. No difference in various
    blood markers of coagulation, inflammation, or
    protein oxidation (e.g., fibrinogen, platelet
    count, CRP, IL-6, TNF- a) were demonstrated
    between particle and filtered air exposure.
    Reference: Carlsten et al.
    (2007,155714)
    
    Subjects: 13 healthy adults
    
    Gender: 11 M/2 F
    
    Age: 20-42 yr
    DE
    
    2002 Cummins B-series
    diesel engine (6BT5.9G6,
    5.9 L) operating at load
    
    Concentration: Fine PM:
    100, 200 ug/m3
                              Subjects exposed for 2 h at rest to filtered air
                              and each of the two DEPs concentrations in a
                              randomized crossover study design.
                              Exposures were separated by at least 2 wk.
                              Other diesel emissions measured: N02 (10-35
                              ppb), CO (0.7-1.8 ppm).
    
                              Time to analysis: 3, 6, and 22 h after the
                              start of exposure.
    No statistically significant changes in
    plasminogen activator inhibitor-1 (PAI-1), vWf,
    D-dimer, or platelet count observed 3, 6, or
    22 h following exposure to DE relative to
    filtered air. Non-statistically significant
    increases in D-dimer, vWf, and platelet count
    were observed at 6 h following the start of
    exposure (4 h post-exposure). No
    diesel-induced increase in C-reactive protein
    observed relative to filtered air in peripheral
    venous blood at 1 or 20 h post-exposure.
    Reference: Carlsten et al.
    (2008,156323)
    
    Subjects: 16 adults with
    metabolic syndrome
    
    Gender:  10M/6F
    
    Age: 25-48 yr
    DE
    
    2002 Cummins B-series
    diesel engine (6BT5.9G6,
    5.9 L)
    
    Concentration: Fine PM:
    100, 200 ug/m3
                              Subjects exposed for 2 h at rest to filtered air
                              and each of the two DE particle
                              concentrations in a randomized crossover
                              study design. Exposures were separated by at
                              least 2 wk. Other diesel emissions measured:
                              N02 (30 ppb), NO (1.69 ppm), CO (0.65 ppm).
    
                              Time to analysis: 3, 7, and 22 h after the
                              start of exposure.
    At 5 h after the end of diesel exposure (fine
    particulate concentration 200 ug/nv), the
    authors observed a significant decrease in vWf
    in peripheral venous blood. No other changes
    in thrombotic markers (vWf, D-dimer, PAI-1)
    were observed at either concentration between
    1 and 20 h post-exposure.
    Reference: Danielsen et al.
    (2008,156382)
    
    Subjects: 13 healthy adults
    
    Gender: 6 M/7 F
    
    Age: 20-56 yr
    Wood smoke
    
    Particle Size:
    
    Session 1: GMD 42 nm;
    Session 2: GMD 112 nm
    
    Particle Number/Count:
    Session 1:180,000/cm3;
    Session 2:95,000/cm3
    
    Concentration:
    
    Session 1: median:
    279 ug/m3;
    Session 2: median
    243 ug/m3
                              Subjects exposed in two groups for 4 h to
                              filtered air, followed a wk later by a 4-h
                              exposure to wood smoke. Exposures
                              conducted with two 25-min periods of light
                              exercise. Other measured combustion
                              products:
    
                              Session 1: N02 (0.08 ppm), CO (13 ppm),
                              formaldehyde (114 ug/m), acetaldehyde
                              (75 ug/m3), benzene (30 ug/m3),
                              1,3-butadiene (6.3 ug/m3);
    
                              Session 2: N02 (0.09 ppm), CO (9.1 ppm),
                              formaldehyde (64 ug/nv), acetaldehyde
                              (40 ug/m3), benzene (20 ug/m3),
                              1,3-butadiene (3.9 ug/m3).
    
                              Time to analysis: 3 and 20 h post-exposure.
    Exposure to wood smoke increased the mRNA
    levels of hOGG1 in PBMCs relative to filtered
    air 20 h after exposure. DNA strand breaks
    were shown to decrease in PBMCs 20 h after
    wood smoke exposure.
    Reference: Devlin et al.
    (2003, 087348)
    
    Subjects: 10 healthy older
    adults
    
    Gender: 7 M/3 F
    
    Age: Avg 66.9 yr
    Fine CAPs (Chapel Hill, NC) Exposures conducted for 2 h at rest to filtered
                              air and CAPs in a randomized crossover
                              study design.
    Concentration: Mean:
    40.5 ug/m3, Range:
    21.2-80.3 ug/m3
                              Time to analysis: Immediately following
                              exposure and 24 h post-exposure.
    CAPs exposure resulted in statistically
    significant reductions (p <0.05) in time domain
    (PNN50) and frequency domain (HF power)
    parameters relative to clean air immediately
    following exposure. These relative decreases
    were still apparent 24 h after exposure (p
    <0.08).
    December 2009
                                            C-2
    

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              Study
            Pollutant
                    Exposure
                     Findings
    Reference: Fakhri et al.
    (2009,191914)
    
    Subjects: 50 adults (40
    healthy, 10 asthmatic)
    
    Gender: 24 M/26 F
    
    Age: 19-48yr
    Fine CAPs (Toronto)
    
    Concentration: 127±
    62 ug/m3 with and without
    co-exposure to 03 (114 ±
    ppb)
    Exposures conducted through a facemask
    which covered the subject's nose and mouth.
    Subjects were exposed to CAPs, 03, CAPs +
    03 and filtered air for 2 h at rest in a
    randomized crossover study design.
    
    Time to analysis: Every 30 min during
    exposure, with the final measurement made
    immediately prior to the end of the exposure.
    Exposure to CAPs or 03, alone or in
    combination, resulted in no significant changes
    in HRV or blood pressure relative to filtered air.
    However, a negative concentration response
    relationship was reported between CAPs
    concentration with co-exposure to 03 and
    SDNN, rMSSD, HF power and LF power
    (statistically significant for LF power). Diastolic
    blood pressure was observed to  increase with
    exposure to CAPs + 03, but not with either
    pollutant alone. There was no difference in
    response between asthmatics and healthy
    subjects.
    Reference: Frampton et al.
    (2006, 088665)
    
    Subjects: 16 asthmatic
    adults, 40 healthy adults
    
    Gender: Asthmatics:
    8 M/8 F, Healthy: 20 M/20 F
    
    Age: 18-40yr
    Ultrafine EC
    
    Particle Size: CMD -25 nm
    
    Particle Number/Count:
    10 ug/m3:-2.0 xioW;
    25ug/m3:~7.0xio6/cm3;
    50ug/m3:~10.8xio6/cm3
    
    Concentration:  10,25, and
    50 ug/m3
    Study conducted using a randomized
    crossover design with 2-h exposures.
    Asthmatics (n = 16) exposed to filtered air and
    10 ug/m3.12 healthy adults exposed to filtered
    air and 10 ug/m3 at rest; 12 healthy adults
    exposed to filtered air, 10  and 25 ug/m3 with
    intermittent exercise; 16 healthy adults
    exposed to filtered air and 50 ug/m with
    intermittent exercise. Exposures were
    conducted via mouthpiece.
    
    Time to analysis: Immediately following
    exposure as well as 3.5,21, and 45 h post-
    exposure.
    No effect of ultrafine particle exposure on
    leukocyte counts or leukocyte expression of
    adhesion molecules observed in healthy
    subjects exposed at rest to 10 ug/m3. Among
    healthy adults exposed to ultrafine carbon
    during exercise, monocyte expression of
    adhesion molecules CD54 and CD18
    decreased relative to filtered air immediately
    following exposure. An ultrafine
    particle-induced decrease in PMN expression
    of CD18 was also observed 0-21 h
    post-exposure. Expression ofCDHbon
    monocytes and eosinophils was  reduced
    following exposure to ultrafine particles  in
    exercising asthmatics 0-21 h post-exposure. A
    decrease in total leukocyte count was
    observed following ultrafine particle exposure
    in exercising healthy and asthmatic subjects.
    Reference: Gong et al.
    (2004, 087964)
    
    Subjects: 13 older adults
    with COPD, 6 healthy older
    adults
    
    Gender: COPD: 5 M/8 F,
    Healthy: 2 M/4 F
    
    Age: COPD:avg 68 yr,
    Healthy: avg 73 yr
    Fine CAPs (Los Angeles)
    
    Particle Size: 85% of mass
    between 0.1 and 2.5 urn
    
    Concentration: Mean:
    194 ug/m3, Range:
    135-229 ug/m3
    Exposures to CAPs and filtered air
    (randomized crossover) for 2 h with
    intermittent light exercise (four 15-min
    periods). Exposures were separated by at
    least 2 wk.
    
    Time to analysis: Immediately following
    exposure as well as 4 and 22 h post-
    exposure.
    SDNN shown to decrease following CAPs
    exposure relative to filtered air in healthy older
    adults (4-22 h post-exposure). No
    CAPs-induced changes in HRV were observed
    in older adults with COPD. Ectopic heart beats
    were observed to increase slightly with CAPs
    relative to filtered air among healthy subjects,
    but decreased among subjects with COPD.
    Exposure to CAPs  did not affect platelet or
    white blood cell count, or levels of fibrinogen,
    vWF, or factor VII.
    Reference: Gong et al.
    (2004, 055628)
    
    Subjects: 12 adult
    asthmatics, 4 healthy adults
    
    Gender: Asthmatics:
    4 M/8 F, Healthy: 2 M/2 F
    
    Age: Asthmatics: avg 38 yr,
    Healthy: avg 32 yr
    Coarse CAPs (Los Angeles)
    
    Particle Size: 80% of mass
    between 2.5 and 10 urn,
    20% of mass <2.5  urn
    
    Concentration: Mean:
    157 ug/m , Range:
    56-218 ug/m3
    Exposures to CAPs and filtered air
    (randomized crossover) for 2 h with
    intermittent light exercise (four 15-min
    periods). Exposures were separated by at
    least 2 wk.
    
    Time to analysis: Immediately following
    exposure as well as 4 and 22 h post-
    exposure.
    SDNN shown to decrease following CAPs
    exposure relative to filtered air in healthy
    adults (4-22 h post-exposure). Decrease in
    PNN50 also observed in healthy adults at 4 h
    post-exposure. No CAPs-induced decreases in
    HRV demonstrated in asthmatics.
    Reference: Gong et al.
    (2008,156483)
    Ultrafine CAPs (Los
    Angeles)
    Subjects: 14 adult           Particle Number/Count:
    asthmatics,  17 healthy adults  145,000/cm3, Range
                               39,000-312,000/cm3
    Gender: Asthmatics:
    9 M/5 F, Healthy: 5 M/12 F    Concentration: Mean-
                               100 ug/m , Range-
    Age: Asthmatics: 34 ± 12 yr,  -| 3.277 uq/m3
    Healthy: 24  ± 8 yr                  Ha
    Subjects exposed for 2 h during intermittent
    exercise (15-min periods) to both CAPs and
    filtered air in random order. The first 7
    subjects underwent whole body exposure,
    while the remaining subjects were exposed
    through a facemask. Facemask exposures
    had higher particle counts but lower particle
    mass than whole body exposures. Exposures
    were separated by at least 2 wk.
    
    Time to analysis: Immediately following
    exposure as well as 4 and 22 h post-
    exposure.
    Relative to filtered air, exposure to ultrafine
    CAPs resulted in a transient decrease in LF
    power 4 h post-exposure. This effect of CAPs
    on HRV was not influenced by health status.
    CAPs exposure was not observed to affect any
    other measures of HRV, blood pressure, or
    blood markers of inflammation or coagulation.
    There were no differences in response
    observed between facemask and whole body
    exposures.
    December 2009
                                           C-3
    

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              Study
            Pollutant
                                              Exposure
                                                                                        Findings
    Reference: Graff etal.
    (2009,191981)
    
    Subjects: 14 healthy adults
    
    Gender: 8 M/6 F
    
    Age: 20-34 yr
    Coarse CAPs (Chapel Hill,
    NC)
    
    Concentration: 89
    ±49.5 ug/m3 (estimated
    inhaled dose * 67% of
    measured particle mass)
                              Subjects exposed for 2 h with intermittent
                              exercise (15-min periods) to coarse CAPs and
                              filtered air in a randomized crossover design.
                              Exposures were separated by at least 2 mos.
    
                              Time to analysis: 0-1 and 20 h post-
                              exposure.
                                                                       At 20 h post-exposure, tPAwas observed to
                                                                       decrease by 32.9% from baseline (pre-
                                                                       exposure) per 10 ug/m3 increase in CAPs
                                                                       concentration (p = 0.01). D-dimer
                                                                       concentration decreased 11.3% per 10 ug/m3,
                                                                       a change of marginal statistical significance (p
                                                                       = 0.07). No other coarse CAPs-induced
                                                                       changes in blood biomarkers of coagulation
                                                                       (e.g.,vWF, factor VII, plasminogen, fibrinogen,
                                                                       or PAI-1) or inflammation (e.g., CRP) were
                                                                       observed. At 20 h post-exposure, overall HRV
                                                                       (SDNN) was shown to decrease by 14.4%
                                                                       relative to  pre-exposure measurements per
                                                                       10 ug/m3 increase in CAPs concentration. No
                                                                       other changes in  HRV were observed following
                                                                       exposure to coarse CAPs.
    Reference: Huang et al.
    (2003, 087377)
    
    Subjects: 38 healthy adults
    
    Gender: 36 M/2 F
    
    Age: Avg 26.2 ±0.7 yr
    Fine CAPs (Chapel Hill, NC)  Subjects exposed to CAPs (n = 30) or filtered  The increase in blood fibrinogen following
                              air (n = 8) for 2 h with intermittent exercise     exposure to fine CAPs reported by Ghio et al.
                              (subjects did not serve as their own controls).  (2000, 012140) was shown to be associated
                              Component data of CAPs was available for 37 with copper, zinc, and vanadium content in the
                              of the 38 subjects.                         CAPs.
    
                              Time to analysis: 18 h after exposure.
    Concentration:
    23.1-311.1 ug/m3
    Reference: Larsson et al.
    (2007, 091375)
    
    Subjects: 16 healthy adults
    
    Gender: 10 M/6 F
    
    Age: 19-59yr
    Traffic particles (road
    tunnel)
    Particle Size: PM25, PM10;
    PM25 mass constituted
    ~36%ofPM10mass
    
    Particle Number/Count:
    20-1,000 nm: 1.1  xio5/cm3,
    < 100 nm: 0.85 xio5/cm3
    
    Concentration: PM25-
    46-81 ug/m3; PM10-
    130-206 ug/m3
    
    DE
    
    Protocol 1 (n=8): idling
    Deutz diesel engine
    (F3M2011,2.2 1,500 rpm)
    using gas oil
    
    Protocol 2 (n=12): idling
    Volvo diesel engine (TD45,
    4.5 L, 4 cylinders, 680 rpm)
    using Gasoil E10
    
    Particle Number/Count:
    Protocol!: 1.2 xio6/cm3;
    Protocol 2:1.26 xio6/cm3
    
    Concentration: Protocol 1:
    348 ug/m3, Protocol 2:
    330 ug/m3
                              Exposures were conducted for 2 h with
                              intermittent exercise in a room adjacent to a
                              busy road tunnel. Study used a randomized
                              crossover design with each subject also
                              exposed to normal air (control). Exposures
                              were separated by 3-10 wk. No exposures to
                              filtered air were conducted. Other traffic
                              emissions  measured: NO (874 ug/m3), N02
                              (230 ug/m), CO (5.8 ug/m reported, likely
                              5.8 mg/m3).
    
                              Time to analysis:  14 h post-exposure.
                                                                        No change in plasma levels of fibrinogen or
                                                                        PAI-1 observed 14 h post-exposure.
    Reference: Lucking et al.
    (2008,191993)
    
    Subjects: 20 healthy adults
    
    Gender: M
    
    Age: 21-44yr
                              In both protocols, exposures were conducted
                              with intermittent exercise (15-min periods) to
                              DE and filtered air in a randomized crossover
                              design with exposures separated by at least
                              one wk.
    
                              Protocol 1  (n=8): Exposures conducted for 2
                              h. Other diesel emissions measured: NOX
                              (0.58 ppm), N02 (0.23 ppm), NO (0.36 ppm)
                              CO (3.54 ppm), total hydrocarbon (2.8 ug/m ).
    
                              Time to analysis: 6 h post-exposure.
    
                              Protocol 2  (n= 12): Exposures conducted for
                              1h. Other diesel emissions measured: NOX
                              (2.78 ppm), N02 (0.62 ppm), NO (2.15 ppm),
                              CO (3.08 ppm), total hydrocarbon
                              (1.58 ug/m).
    
                              Time to analysis: 2 and 6 h post-exposure.
                                                                       Thrombus formation was observed to increase
                                                                       with diesel 2 and 6 h post-exposure using an
                                                                       ex vivo perfusion chamber. Both platelet-
                                                                       neutrophil and platelet-monocyte aggregates
                                                                       increased relative to filtered air 2 h following
                                                                       exposure to diesel (only evaluated in Protocol
                                                                       2). Plasma concentrations of soluble CD40L
                                                                       were also observed to increase with diesel.
                                                                       Exposure to diesel was not shown to affect
                                                                       total leukocyte, monocyte, or platelet counts.
    Reference: Lund et al.
    (2009,180257)
    
    Subjects: 10 healthy adults
    
    Gender: 4 M/6 F
    
    Age: 18-40yr
    DE
    
    Idling Cummins diesel
    engine (5.9 L) using
    commercial No. 2 fuel
    
    Particle Size: MMAD
    0.10 urn
    
    Concentration: 100 ug/m3
                              Subjects exposed for 2 h with intermittent
                              exercise (15-min periods) to DE and filtered
                              air in a randomized crossover study design.
                              Other diesel emissions measured: NOX (4.7
                              ppm), N02 (0.8 ppm), CO (2.8 ppm), total
                              hydrocarbons (2.4 ppm).
    
                              Time to analysis: 30 min and 24 h post-
                              exposure.
                                                                        Exposure to diesel resulted in an increase
                                                                        in MMP-9 plasma concentration and activity as
                                                                        well as an increase in endothelin-1 plasma
                                                                        concentration at both 30 min and 24 h post-
                                                                        exposure.
    December 2009
                                           C-4
    

    -------
              Study
            Pollutant
                    Exposure
                     Findings
    Reference: Lundback et al.
    (2009,191967)
    
    Subjects: 12 healthy adults
    
    Gender: M
    
    Age: 21-30 yr
    DE
    
    Idling Volvo diesel engine
    (TD45,4.5 L, 4 cylinders,
    680 rpm) using Gasoil E10
    
    Particle Number/Count:
    1.26xio6/cm3
    
    Concentration: 330 ug/m3
    Subjects exposed for 1 h with intermittent
    exercise (15-min periods) to DE and filtered
    air in a randomized crossover study design.
    Exposures were separated by at least one wk.
    Other diesel emissions measured: NOX (2.78
    ppm), N02 (0.62 ppm), NO (2.15 ppm), CO
    (3.08 ppm), total hydrocarbon (1.58 ug/m ).
    
    Time to analysis: 10,20,30, and 40 min
    post-exposure.
    Diesel-induced increase in arterial stiffness
    (increases in augmentation pressure and
    augmentation index, as well as decrease in
    time to wave reflection) observed at 10 and 20
    min post-exposure using radial artery pulse
    wave analysis. No effect of diesel observed on
    carotid-femoral pulse wave velocity which was
    assessed 40 min post-exposure, but not at
    earlier time points. No effect of diesel observed
    on blood pressure 10-30 min post-exposure.
    Reference: Mills et al.
    (2005, 095757)
    
    Subjects: 30 healthy adults
    
    Gender: M
    
    Age: 20-38 yr
    DE
    
    Idling 1991 Volvo diesel
    engine (TD45, 4.5 L, 4
    cylinders, 680 rpm)
    
    Particle Number/Count:
    1.2xio6/cm3
    
    Concentration: 300 ug/m3
    Subjects exposed for 1 h with intermittent
    exercise (15-min periods) to DE and filtered
    air in a randomized crossover study design.
    Exposures were separated by two wk. Other
    diesel emissions measured: N02 (1.6 ppm),
    NO (4.5 ppm), CO (7.5 ppm), total
    hydrocarbon (4.3 ppm), formaldehyde
    (0.26 ug/m).
    
    Time to analysis: 2-4 h post-exposure for 15
    subject; 6-8 h post-exposure for the other 15
    subjects.
    Forearm blood flow increase (induced by
    bradykinin, acetylcholine, and sodium
    nitroprusside) was attenuated by DE 2 and 6 h
    post-exposure. A6 mmHg increase in diastolic
    blood pressure (p = 0.08) 2 h following
    exposure to DE was observed relative to
    filtered air control. Bradykinin-induced release
    of t-PA was attenuated by diesel exposure 6 h
    post-exposure. DE did not affect the release of
    t-PA 2 h post-exposure. No diesel-induced
    changes in serum IL-6 or TNF-a observed 6 h
    post-exposure.
    Reference: Mills et al.
    (2007, 091206)
    
    Subjects: 20 older adults
    with prior myocardial
    infarction
    
    Gender: M
    
    Age: 60 ± 1 yr
    DE
    
    Idling 1991 Volvo diesel
    engine (TD45, 4.5 L, 4
    cylinders, 680 rpm)  using
    low sulfur gas-oil E10
    
    Particle Size: Median
    particle diameter 54 nm,
    Range 20-120 nm
    
    Particle Number/Count:
    1.26xio6/cm3
    
    Concentration: 300 ug/m3
    Subjects exposed for 1 h with intermittent
    exercise (15-min periods) to DE and filtered
    air in a randomized crossover study design.
    Exposures were separated by at least two wk.
    Other diesel emissions measured: NOX (4.45
    ppm), N02 (1.01 ppm), NO (3.45 ppm), CO
    (2.9 ppm), total hydrocarbon  (2.8 ppm).
    
    Time to analysis: During exposure and 6-8 h
    post-exposure.
    A greater increase in exercise induced
    ST-segment depression and ischemic burden
    was observed during exposure to DE than
    clean air. No diesel-induced effects on
    vasomotor dysfunction observed 6 h
    post-exposure. Bradykinin-induced release of
    t-PA was attenuated by diesel exposure
    relative to filtered air 6 h post-exposure. Effect
    of diesel on t-PA release was not evaluated at
    earlier times post-exposure. No diesel-induced
    changes in blood leukocyte counts or serum
    C-reactive protein 6 h post-exposure.
    Reference: Mills et al.
    (2008,156766)
    
    Subjects: 12 adults with
    coronary heart disease, 12
    healthy adults
    
    Gender: M
    
    Age:CHD:59±2yr,
    Healthy: 54 ± 2 yr
    Fine CAPs (Edinburgh,
    Scotland, UK)
    
    Particle Size: Mean
    1.23 urn
    
    Particle Number/Count:
    99,400/cm3
    
    Concentration:
    190 ±37 ug/m3
    Exposures conducted for 2 h with intermittent
    exercise. Subjects exposed to CAPs and
    filtered air using a randomized crossover
    design with exposures separated by at least 2
    wk.
    
    Time to analysis: 2,6-8, and 24 h post-
    exposure.
    CAPs exposure had no significant effect on
    vascular function in healthy adults or adults
    with coronary heart disease 6-8 h
    post-exposure (i.e., no change in  forearm
    blood flow as assessed using venous
    occlusion plethysmographyj.The authors
    attributed this lack of response to a low
    concentration of combustion-derived particles.
    Small increase in blood platelet and monocyte
    concentration observed following  CAPs
    exposure. Exposure to CAPs did  not affect
    serum CRP concentration or total leukocyte or
    neutrophil count.
    Reference: Peretz et al.
    (2007,156853)
    
    Subjects: 5 healthy adults
    
    Gender: M
    
    Age: 20-31 yr
    DE
    
    2002 Cummins B-series
    diesel engine (6BT5.9G6,
    5.9 L); operating at 75% of
    rated capacity
    
    Concentration: Fine PM
    50,100, 200 ug/m3
    Subjects exposed for 2 h at rest to filtered air
    and each of the three DE particle
    concentrations in a randomized crossover
    study design. Exposures were separated by at
    least 2 wk. Other diesel emissions measured,
    200 ug/m3 exposure: N02 (23 ppb), NO (1.75
    ppm), CO (1.58 ppm).
    
    Time to analysis: 6 and 22 h after the start of
    exposure.
    PBMC expression of 10 genes involved in the
    inflammatory response were observed to be
    significantly affected by exposure to DE at the
    highest concentration tested (8 upregulated, 2
    downregulated) 6 h after the start of exposure.
    The expression of 4 genes (1 upregulated, 3
    downregulated) associated with the
    inflammatory response showed significant
    changes 22 h after diesel exposure. PBMC
    expression of 5 genes involved in the oxidative
    stress pathways showed significant changes at
    6 h after the start of diesel exposure at the
    highest concentration tested (4 upregulated, 1
    downregulated). 7 genes involved in the
    oxidative stress pathways showed significant
    changes at 22 h following exposure (4
    upregulated, 3 downregulated).
    December 2009
                                           C-5
    

    -------
              Study
            Pollutant
                    Exposure
                     Findings
    Reference: Peretz et al.
    (2008,156854)
    
    Subjects: 17 adults with
    metabolic syndrome, 10
    healthy adults
    
    Gender:  Metabolic
    syndrome: 11 M/6 F,
    Healthy: 8 M/2 F
    
    Age: Metabolic syndrome:
    20-48 yr,  Healthy: 20-42 yr
    DE
    
    2002 Cummins B-series
    diesel engine (6BT5.9G6,
    5.9 L) using No. 2 undyed
    on-highway fuel; operating
    at 75% of rated capacity
    
    Particle Size: Median
    particle diameter 1.04 urn
    
    Concentration: Fine PM
    100, 200 ug/m3
    Subjects exposed for 2 h at rest to both
    concentrations of DE as well as filtered air in a
    randomized crossover design. Exposures
    were separated by at least 2 wk. Other diesel
    emissions measured, 100 ug/m3 exposure:
    N02 (16.5 ppb), NO (0.96 ppm), CO (0.51
    ppm); 200 ug/m  exposure: N02 (24.7 ppb),
    NO (1.54 ppm), CO (0.89 ppm).
    
    Time to analysis:  Immediately following
    exposure (within 30 min post-exposure) and
    3 h from the start of exposure.
    Exposure to 200 ug/m  elicited a statistically
    significant decrease in brachial artery diameter
    relative to filtered air immediately following
    exposure. A smaller decrease in brachial artery
    diameter was also observed following
    exposure to DE at 100 ug/m3. Plasma  levels of
    endothelin-1 were observed to increase
    following DE exposure (200 ug/m3). The
    observed effects were more pronounced in
    healthy subjects than in subjects with
    metabolic syndrome. DE did not affect
    endothelium-dependent flow-mediated
    dilatation. No effect of DE on blood pressure
    was demonstrated immediately following
    exposure.
    Reference: Peretz et al.
    (2008,156855)
    
    Subjects: 13 adults with
    metabolic syndrome, 3
    healthy adults
    
    Gender:  Metabolic
    syndrome: 8 M/5 F, Healthy:
    3M/OF
    
    Age: Metabolic syndrome:
    31-48 yr,  Healthy: 24-39 yr
    DE
    
    2002 Cummins B-series
    diesel engine (6BT5.9G6,
    5.9 L) using No. 2 undyed
    on-highway fuel; operating
    at 75% of rated capacity
    
    Concentration: Fine PM
    100, 200 ug/m3
    Subjects exposed for 2 h at rest to both
    concentrations of DE as well as filtered air in a
    randomized crossover design. Exposures
    were separated by at least 2 wk. Other diesel
    emissions measured, 100 ug/m3 exposure:
    N02 (20.6 ppb), NO (0.95 ppm), CO (0.47
    ppm); 200 ug/m3 exposure: N02 (28.3 ppb),
    NO (1.63 ppm), CO (0.74 ppm).
    
    Time to analysis:  1, 3, 6, and 22 h from the
    start of exposure.
    Exposure to 200 ug/m  increased HF power
    and decreased the LF/HF ratio 1h
    post-exposure; however, this effect was not
    consistent across subjects. No effect of DE
    was observed at later time points. Subjects
    with metabolic syndrome did not experience
    greater changes in HRVthan healthy subjects.
    Reference: Power et al.
    (2008,191982)
    Carbon and ammonium
    nitrate particles
    Subjects: 5 adults with mild-  Concentration:
    to-moderate allergic asthma
    Gender: 1 M/4 F
    
    Age: 28-51 yr
    With co-exposure to 0.2ppm
    03:255 ug/m3,
    
    Without co-exposure to
    0.2ppm03:313ug/m3
    Subjects exposed for 4 h with intermittent
    exercise (30-min periods) to filtered air,
    particles, and particles + 03 in a crossover
    study design. Exposures were separated by at
    least 3 wk.
    
    Time to analysis: 3 h 40 min from the start of
    exposure.
    Time and frequency domain HRV parameters
    were not affected by particle exposure relative
    to filtered air. However, exposure to particles
    with 03 resulted in a significant decrease in
    SDNN as well as  changes to both high and low
    frequency power  normalized to the difference
    between total and very low frequency power.
    Reference: Routledge et al.
    (2006, 088674)
    
    Subjects: 20 older adults
    with coronary artery disease,
    20 healthy older adults
    
    Gender: CAD: 17 M/3F,
    Healthy: 10M/1 OF
    
    Age: CAD: 52-74yr,
    Healthy: 56-75 yr
    Ultrafine carbon
    
    Particle Size: <10-300 nm;
    mode at 20-30 nm
    
    Concentration: Ultrafine
    carbon: 50 ug/m3; S02:200
    ppb
    Exposures conducted (head dome system) to
    filtered air, Ultrafine carbon, S02, and Ultrafine
    carbon + S02 for 1 h at rest using a
    randomized crossover study design.
    
    Time to analysis: Immediately following
    exposure as well as 3 and 23 h post-
    exposure.
    No PM-induced changes in HRV observed
    among subjects with coronary artery disease.
    Among healthy subjects, small increase in
    HRV (RR, SDNN, rMSSD, and LF power)
    demonstrated immediately post-carbon
    exposure. Relative to filtered air control,
    exposure to Ultrafine carbon did not
    significantly affect blood pressure in healthy
    adults or adults with coronary artery disease
    0-3 h post-exposure. Exposure to Ultrafine
    carbon, either alone or with S02, did not affect
    plasma levels of fibrinogen or D-dimer at 3 or
    23 h post-exposure. Exposure to Ultrafine
    carbon did not affect peripheral blood
    leukocyte count or C-reactive protein levels 3
    or 23 h post-exposure.
    Reference: Rundell and      Gasoline emissions
    Caviston (2008,191986)
                               2.5 hp gasoline engine
    Subjects:  15 healthy college  running 10 s each min
    athletes                    during exposure and in the
                               min prior to exposure
    Gender: M
    
    Age: Avg 19.5yr
    Particle Size: PM1.0
    
    Particle Number/Count:
    Trial!: 336,730 ±
    149,206/cm3;
    
    Trial 2:396,200 ±
    82,564/cm3
    Subjects were exposed twice to both clean air
    and dilute gasoline exhaust during 6-min
    periods of maximal exercise on a cycle
    ergometer. Clean air exposures occurred first
    and were separated by 3 days. Gasoline
    exhaust exposures were also separated by 3
    days, with the first occurring 7 days after the
    second clean air exposure. Other emissions
    measured: CO (6.3 ± 3.4 ppm).
    
    Time to analysis: 6  min
    There was no difference in total work done (kJ)
    between the clean air exposures or between
    the clean air exposures and the first exposure
    to gasoline exhaust. However, the second
    gasoline exhaust exposure was demonstrated
    to significantly decrease work accumulated
    over the 6min exercise period compared with
    either of the other exposure conditions (p <
    0.01).
    December 2009
                                           C-6
    

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              Study
            Pollutant
                    Exposure
                     Findings
    Reference: Samet et al.
    (2007,156940)
    
    Subjects: Ultrafine CAPs:
    20 healthy adults, Coarse
    CAPs: 14 healthy adults
    
    Gender: Ultrafine CAPs:
    11 M/9F, Coarse CAPs:
    8M/6F
    
    Age: Ultrafine CAPs:
    18-35yr, Coarse CAPs:
    18-35yr
    CAPs (Chapel Hill, NC)
    
    Particle Size: Ultrafine
    0.049 ± 0.009 urn; Coarse
    3.59 ± 0.58 urn
    
    Concentration: Ultrafine
    47.0 ±20.2 ug/m3; Coarse
    89.0 ±49.5 ug/m3
    Preliminary report comparing effects of
    controlled exposures to coarse, fine, and
    Ultrafine CAPs among healthy adults (3
    separate studies). A randomized crossover
    design was used in evaluating effects of
    coarse CAPs (n=14) and Ultrafine CAPs
    (n=20) relative to filtered air following 2-h
    exposures with intermittent exercise. Results
    compared with previous study of controlled
    exposure to fine CAPs (Chapel Hill, NC)
    where subjects did not serve as their own
    controls (Ghio et al., 2000, 012140).
    
    Time to analysis: 0-20 h post-exposure.
    Statistically significant decrease in SDNN
    observed 20 h following exposure to coarse
    CAPs relative to filtered air. Subjects in the
    high Ultrafine CAPs group experienced a
    decrease in SDNN based on an analysis of
    24 h ambulatory Holler monitoring relative to
    filtered air. Fine CAPs did not significantly
    affect HRV. Increased levels of D-dimer
    observed 18 h following exposure to Ultrafine
    CAPs. No CAPs-induced changes in plasma
    factor VII, plasminogen, fibrinogen, PAI-1, vWf,
    or t-PA. No CAPs-induced changes in
    C-reactive protein levels were observed.
    Reference: Samet et al.
    (2009,191913)
    
    Subjects: 19 healthy adults
    
    Gender: 10M/9F
    
    Age: 18-35 yr
    Ultrafine CAPs (Chapel Hill,
    NC)
    
    Particle Size: < 0.16 urn
    
    Particle Number/Count:
    120,662 ±48,232
    particles/cm
    
    Concentration: 49.8 ±
    20 ug/m3
    Subjects exposed for 2 h with intermittent 15
    periods of exercise to UF CAPs and filtered
    air using a randomized crossover study
    design.
    
    Time to analysis: Immediately following
    exposure and 1 and 18 h post-exposure.
    UF CAPs exposure resulted in an increase in
    plasma concentrations of D-dimer both
    immediately following exposure (20.6%
    increase per 105 particles/cm3) as well as 18 h
    post-exposure (18.2% increase per 105
    particles/crtv). Plasma concentration of PAH
    also increased with UF CAPs, although this
    increase was not statistically significant (24%
    increase, p = 0.1).  No UF CAPs-induced
    changes observed in plasma concentrations of
    tPA, vWF, CRP, fibrinogen, plasminogen,
    or Factor VII. HF and LF power were both
    observed to increase with UF CAPs exposure
    relative to filtered air at 18 h post-exposure
    (41.8% and 36%, respectively, per 10
    particles/cm3 increase in UF CAPs). UF CAPs
    expressed as mass concentration was not
    observed have a statistically significant effect
    in HF total power. UF CAPs was not observed
    to affect time domain measures of HRV over
    24 h. The QT interval was shown to decrease
    both immediately following and at 18 h post
    exposure (not statistically significant
    immediately following exposure).
    Reference: Shah et al. Ultrafine EC
    (2008, 156970)
    Particle Number/Count:
    Subjects: 16 healthy adults 10.8 ± 1 .7 x 106 /cm3
    Age: 26.9 ± 6.9 yr Concentration: 50 ug/m3
    Exposures conducted via mouthpiece for 2 h
    with intermittent exercise to filtered air and
    Ultrafine carbon in a randomized crossover
    study design.
    Time to analysis: Immediately following
    exposure as well as 3.5, 21 , and 45 h post-
    exposure.
    Exposure to Ultrafine carbon attenuated peak
    forearm blood flow after ischemia relative to
    filtered air 3.5 h post-exposure. Venous nitrate
    levels were significantly lower at 21 h following
    exposure to UF carbon compared with filtered
    air exposure. PM exposure was not observed
    to affect blood pressure relative to filtered air at
    times 0-45 h post-exposure.
    Reference: Tornqvist et al.
    (2007, 091279)
    
    Subjects: 15 healthy adults
    
    Gender: M
    
    Age: 18-38yr
    DE
    
    Idling 1991 Volvo diesel
    engine (TD45, 4.5 L, 4
    cylinders, 680 rpm)
    
    Concentration: 300 ug/m3
    Subjects exposed for 1 h with intermittent
    exercise (15-min periods) to DE and filtered
    air in a randomized crossover study design.
    Exposures were separated by at least two wk.
    Other diesel emissions measured: NOX (4.44
    ppm), N02 (0.82 ppm), NO (3.62 ppm), total
    hydrocarbon (2.21  ppm).
    
    Time to analysis:  24  h post-exposure.
    DE was observed to significantly attenuate
    endothelium-dependentvasodilation 24 h
    post-exposure. Endothelium-independent
    vasodilation was not affected by diesel
    exposure. Exposure to DE did not affect blood
    pressure  relative to filtered air 24 h after
    exposure. DE significantly increased plasma
    levels of IL-6 and TNF-a 24 h following
    exposure. Exposure to diesel resulted in an
    increase in total antioxidant capacity of plasma
    relative to filtered air 24 h post-exposure.
    Reference: Urch et al.
    (2004, 055629)
    
    Subjects: 24 healthy adults
    
    Gender:! 4 M/1 OF
    
    Age: 35±10yr
    Fine CAPs (Toronto)
    
    Concentration: 150 ug/m3
    (range 101-257 ug/m) with
    120ppb03
    Exposures conducted through a facemask
    which covered the subject's nose and mouth.
    Subjects were exposed to CAPs + 03 and
    filtered air for 2 h at rest in a randomized
    crossover study design. Exposures were
    separated by at least 2  days.
    
    Time to analysis: Immediately following
    exposure.
    CAPs + 03 exposure resulted in a significant
    decrease in brachial artery diameter
    immediately post-exposure (Brook et al., 2002,
    024987). which was demonstrated to be
    associated with both the organic and EC
    fractions of the CAPs.
    December 2009
                                           C-7
    

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              Study
            Pollutant
                    Exposure
                     Findings
    Reference: Urch et al.
    (2005, 081080)
    
    Subjects: 23 healthy adults
    
    Gender:! 3 M/1 OF
    
    Age: 32±10yr
    Fine CAPs (Toronto);
    
    Concentration: 150 ug/m3
    (range 102-214 ug/m) with
    120ppb03
    Exposures conducted through a facemask
    which covered the subject's nose and mouth.
    Subjects were exposed to CAPs + 03 and
    filtered air for 2 h at rest in  a randomized
    crossover study design.
    
    Time to analysis: Every 30 min during
    exposure, with the final measurement made
    immediately prior to the end of the exposure.
    An increase in diastolic blood pressure of 6
    mmHg was observed at the end of CAPs + 03
    exposure, which was statistically different from
    the change in blood pressure experienced
    during exposure to filtered air (1 mmHg). This
    effect was associated with the organic fraction
    ofPM2.5.
    Reference: Zarebaetal.
    (2009,190101)
    
    Subjects: 24 healthy adults
    
    Gender: 12 M/12 F
    
    Age: 18-40yr
    Ultrafine EC
    
    Particle Size: Count
    median diameter 25 nm
    
    Particle Number/Count:
    2x106/cm3(10ug/m3),
    7x106/cm3(25ug/m3)
    
    Concentration: 10 ug/m3;
    25 ug/m3
    Protocol 1 (n=12, 6 M/6 F): Subjects exposed
    to 10 ug/m  UF carbon and filtered air for 2 h
    at rest in a randomized crossover design.
    Exposures were separated by at least 2 wk.
    
    Protocol 2 (n=12, 6 M/6 F): Subjects exposed
    to 10 ug/m , 25 ug/m3, and filtered air for 2 h
    with intermittent exercise (15-min periods) in a
    restricted randomized crossover design (all
    subjects exposed to 10 ug/m3 before
    25 ug/m3). Exposures were separated by at
    least 2 wk.
    
    Time to analysis (both protocols):
    Immediately following exposure and 3.5 and
    21 h  post-exposure.
    Exposure to 10 ug/m at rest resulted in no
    change in HRV frequency domain parameters
    relative to filtered air exposure. Time domain
    parameters were observed to increase slightly
    with UF carbon exposure (10 ug/m at rest),
    however, only the increase in rMSSD was
    statistically significant (p = 0.032). Some
    trends toward less shortening of QT interval,
    increase in ST segment, and increase in
    variability of repolarization (variability of T
    wave complexity) were observed with
    exposure to 10 ug/m3 at rest, none of which
    were statistically significant.
    
    In Protocol 2, exposure to 10 ug/m3 UF carbon
    was observed to slightly increase HRV time
    domain parameters  as was demonstrated in
    Protocol 1. However, this was not observed at
    the higher concentration (25 ug/m3). As with
    exposure at rest, exposure to UF carbon
    during exercise was observed to affect
    repolarization (reduction in QT duration and
    increase in T-wave amplitude), although this
    effect was not statistically significant.
    December 2009
                                           C-8
    

    -------
    Table C-2.     Respiratory effects.
            Reference
             Pollutant
                                                 Exposure
                      Findings
    Reference: Alexis et al.
    (2006, 1543231
    
    Subjects: 9 healthy adults
    
    Gender: 3 M/6 F
    
    Age: 18-35 yr
    Coarse fraction particles
    (Chapel Hill, NC)
    
    Heat-treated (biologically
    inactive) and non-heated
    particles
    
    Particle Size: MMAD 5 urn
    
    Concentration: 0.65 mg per
    subject
                                Subjects were administered heat-treated
                                PM10.2.5, non-heated PM^.s, and 0.9% saline
                                (control) via nebulization in a randomized
                                crossover study design. Exposures were
                                separated by at least 1 wk.
    
                                Time to analysis: 2-3 h post-inhalation.
    Both heat-treated and non-heated coarse PM
    were observed to increase neutrophil counts in
    induced sputum 2-3 h post-inhalation. Biologically
    active PM (non-heated) induced an increase
    expression of macrophage TNF-a mRNA, eotaxin,
    and immune surface phenotypes on
    macrophages (mCD14, CD11b/CR3,  and
    HLA-DR).
    Reference: Barregard et al.
    (2008, 1556751
    
    Subjects: 13 healthy adults
    
    Gender: 6 M/7 F
    
    Age: 20-56 yr
    Wood smoke
    
    Particle Size:
    
    Session 1: geometric mean
    diameter 42 nm, Session 2:
    geometric mean diameter 112
    nm
    
    Particle Number/Count:
    Session 1:180,000/cm3;
    Session 2: 95,000/cm3
    
    Concentration: Session 1:
    median 279 pg/m3; Session 2:
    median 243 pg/m3
                                Subjects exposed in two groups for 4 h to filtered
                                air, followed a wk later by a 4-h exposure to
                                wood smoke. Exposures conducted with two
                                25-min periods of light exercise. Other measured
                                combustion products:
    
                                Session 1: N02 (0.08 ppm), CO (13 ppm),
                                formaldehyde (114 pg/m ), acetaldehyde
                                (75 pg/m3!, benzene (30 pg/m3), 1,3-butadiene
                                (6.3 pg/m3);
    
                                Session 2: N02 (0.09 ppm), CO (9.1 ppm),
                                formaldehyde (64 pg/m3), acetaldehyde
                                (40 pg/m3!, benzene (20 pg/m3), 1,3-butadiene
                                (3.9 |jg/m3).
    
                                Time to analysis:  Immediately following
                                exposure as well as 3 and 20 h post-exposure.
    Relative to filtered air, exposure to wood smoke
    was observed to increase levels of eNO 3 h
    post-exposure. Serum Clara cell protein
    increased 20 h after wood smoke  exposure.
    Wood smoke was observed to increase levels of
    malondialdehyde in breath condensate
    immediately after as well as 20 h post-exposure.
    Effects of wood smoke on eNO and
    malondialdehyde levels were similar between the
    two sessions of wood smoke exposure. However,
    serum Clara cell protein was significantly
    increased with wood  smoke in session 1 (higher
    particle count) but not in session 2.
    Reference: Bastain et al.
    (2003, 0986901
    
    Subjects: 18 nonsmoking
    adults with positive allergy
    skin test to short ragweed
    
    Gender: 7 M/11  F
    
    Age: 18-38 yr
    DEP
    
    Isuzu diesel engine, 4 cylinder,
    4JB1
    
    Concentration: 0.3 mg in
    200 pi saline
                                Subjects underwent nasal provocation challenge
                                (intranasal spray) with allergen and either DEP or
                                placebo (saline) in a randomized crossover study
                                design. Challenges were separated by 30 days.
                                This protocol was then repeated 30 days after
                                the last exposure.
    
                                Time to analysis: 24 h post-exposure and 4 and
                                8 days after exposure.
    DEP significantly increased allergic responses to
    short ragweed. Relative to allergen + placebo,
    allergen + DEP increased allergen specific IgE
    4days following exposure, and increased IL-4 1
    day post-exposure. The enhancement of allergic
    response with DEP was observed to be
    reproducible within subjects.
    Reference: Beckett et al.
    (2005, 1562611
    
    Subjects: 12 healthy adults
    
    Gender: 6 M/6 F
    
    Age: 23-52 yr
    Ultrafine and fine zinc oxide
    
    Particle Size: UF:
    O.1  pm; Fine: 0.1-1.0 urn
                                Subjects exposed via mouthpiece for 2 h during
                                rest to filtered air, ultrafine, and fine zinc oxide in
                                a randomized crossover study design.
                                Exposures were separated by at least 3 wk.
    No changes observed in neutrophil count in
    induced sputum. No PM (zinc oxide)-induced
    changes in respiratory symptoms observed
    0-24 h post-exposure.
    Particle Number/Count: UF:   71™ to analysis: 11 and 24 h after exposure.
    4.6 x 107cm .Fine: 1.9 x
    4.6xl07<
    105/cm3
    
    Concentration: 500 pg/m3
    Reference: Behndig et al.
    (2006, 0882861
    
    Subjects: 15 healthy adults
    
    Gender: 8 M/7 F
    
    Age: 21-27 yr
    DE
    
    Idling 1991 Volvo diesel
    engine (TD45, 4.5 L, 4
    cylinders, 680 rpm)
    
    Particle Size: PM10; majority
    ofPM mass made up of
    particles < 1 pm in diameter
    
    Concentration: 100 pg/m3
                                Exposures conducted for 2 h with intermittent
                                exercise to both DE and filtered air in a
                                randomized crossover design. Exposures were
                                separated by at least 3 wk. Other diesel
                                emissions measured: NOX (1.8 ppm), N02 (0.4
                                ppm), NO (1.3 ppm), CO (10.4 ppm), total
                                hydrocarbons (1.3 ppm).
    
                                Time to analysis: 18 h post-exposure.
    Exposure to DE increased neutrophil and mast
    cell numbers in bronchial mucosa at 18 h
    post-exposure. Neutrophils,  IL-8, and
    myeloperoxidase observed to increase in
    bronchial lavage fluid following exposure relative
    to filtered air. No inflammatory response observed
    in the alveolar compartment. Exposure to DE
    increased urate and reduced glutathione
    bronchoalveolar lavage at 18 h post-exposure.
    Reference: Blomberg et al.
    (2005, 1919911
    
    Subjects: 15 older adults
    (former smokers) with COPD
    
    Age: 56-72 yr
    DE
    
    Concentration: 300 pg/m3
                                Subjects exposed for 1 h with intermittent
                                exercise to DE and filtered air in a randomized
                                crossover study design.
    
                                Time to analysis: 6 and 24 h post-exposure.
    DE was not observed to affect levels of Clara cell
    protein in peripheral blood at 6 and 24 h post-
    exposure.
    December 2009
                                              C-9
    

    -------
            Reference
             Pollutant
                                                                             Exposure
                                                                                               Findings
    Reference: Bosson et al.
    (2007, 1562861
    
    Subjects: 16 healthy adults
    
    Gender: 7 M/9 F
    
    Age: 20-28 yr
    DE
    
    Idling Volvo diesel engine
    
    Concentration: PM
    300 pg/m  followed by
    exposure to filtered air or 0.2
    ppm03
                                                            Subjects exposed to DE for 1 h followed 5 h later
                                                            by a 2-h exposure to either filtered air or 03 (0.2
                                                            ppm) using a randomized crossover study
                                                            design. All exposures were conducted with
                                                            subjects engaged in intermittent exercise.
    
                                                            Time to analysis: 18 h after second exposure
                                                            (filtered air or 03).
                                                                             The percentage of neutrophils and concentration
                                                                             of myeloperoxidase in induced sputum (18 h
                                                                             post-Os/air exposure) was significantly higher
                                                                             following diesel + 03 than diesel + air.
    Reference: Bosson et al.
    (2008, 1966591
    
    Subjects: 14 healthy adults
    
    Gender: 9 M/5 F
    
    Age: 21-29 yr
    DE
    
    Idling 1991 Volvo diesel
    engine (TD45, 4.5 L, 4
    cylinders)
    
    Concentration: PM
    300 pg/m or filtered air
    followed by exposure to 0.2
    ppm03
                                                            Subjects exposed to DE or filtered air for 1 h
                                                            followed 5 h later by a 2-h exposure to 03 (0.2
                                                            ppm) using a randomized crossover study
                                                            design. All exposures were conducted with
                                                            subjects engaged in intermittent exercise. Other
                                                            diesel emissions measured: N02 (0.51 ppm),  NO
                                                            (1.65 ppm), total hydrocarbons (1.18 ppm).
    
                                                            Time to analysis: 24 h after the start of the initial
                                                            exposure.
                                                                             Neutrophil and macrophage numbers in bronchial
                                                                             wash were significantly increased 16 h following
                                                                             03 exposure when preceded by exposure to
                                                                             diesel, compared to 03 exposure preceded by
                                                                             exposure to filtered air.
    Reference: Brauner et al.
    (2009, 1902441
    
    Subjects: 29 healthy adults
    
    Gender: 20 M, 9 F
    
    Age: M avg 27 yr, F avg 26 yr
    Urban traffic particles
    
    Particle Size: PM2.5, PM10.2.5
    
    Particle Number/Count: 6-
    700nm:10,067/cm3
    
    Concentration: PM25:
    9.7 pg/m3, PMio.25:12.6 pg/m3
                                                            Subjects exposed to urban traffic particles and
                                                            filtered air for 24 h with and without two 90-min
                                                            periods of light exercise in a randomized
                                                            crossover study design. Concentrations of NOX
                                                            and NO were low and did not differ between
                                                            filtered and unfiltered exposures. CO
                                                            concentrations were higher with filtered air (0.35
                                                            and 0.41 ppm), while 03 concentrations were
                                                            lower with filtered air (12.08 and 4.29 ppb).
    
                                                            Time to analysis: 2.5, 6, and 24 h after the start
                                                            of exposure.
                                                                             Epithelial membrane integrity and blood-gas
                                                                             barrier permeability, assessed using pulmonary
                                                                             clearance of 99mTc-labeled diethylenetriamine
                                                                             pentaacetic acid (DTPA), was observed to
                                                                             increase with exercise, but was not affected by
                                                                             exposure to urban particles (2.5 h of exposure).
                                                                             Exposure to urban particles was not shown to
                                                                             affect plasma or urine concentration of Clara cell
                                                                             16 protein at 6 and 24 h after the start of
                                                                             exposure. No relationship between exposure and
                                                                             pulmonary function was observed at 2.5 h.
    Reference: Gilliland et al.
    (2004, 1564711
    
    Subjects: 19 adults with
    allergic rhinitis and positive
    skin test to ragweed, GSTM1
    (14 null, 5 present); GSTT1 (9
    null, 10 present); GSTP1
    codon 105 variants (13 I/I,  6
    IA/, OVA/)
    
    Gender:7M/12F
    
    Age: 20-34 yr
    DEP
    
    Isuzu diesel engine, 4 cylinder,
    4JB1
    
    Concentration: 0.3 mg DEP
    in 300 pL saline
                                                            Subjects were challenged intranasally with
                                                            allergen and placebo (saline) as well as allergen
                                                            plus DEP in saline in a randomized crossover
                                                            design. Challenges were separated by at least 6
                                                            wk.
    
                                                            Time to analysis: 10 min, 24 h, and 72 h post-
                                                            challenge.
                                                                             Subjects who were GSTM1 null or homozygous
                                                                             for GSTP1 1105 wild-type allele experienced
                                                                             significantly greater increase in nasal IgE and
                                                                             histamine with diesel plus allergen compared to
                                                                             subjects with functional GSTM1 or who were
                                                                             heterozygous for GSTP1  IA/(105).
    Reference: Gong et al.
    (2004, 0879641
    
    Subjects: 13 older adults with
    COPD, 6 healthy older adults
    
    Gender: COPD: 5 M/8 F,
    Healthy: 2 M/4 F
    
    Age: COPD: avg 68 yr,
    Healthy: avg 73 yr
    Fine CAPs (Los Angeles)
    
    Particle Size: 85% of mass
    between 0.1 and 2.5pm
    
    Concentration:  Mean:
    194 ug/m , Range:
    135-229 ug/m3
                                                            Exposures to CAPs and filtered air (randomized
                                                            crossover) for 2 h with intermittent light exercise
                                                            (four15-min periods). Exposures were separated
                                                            by at least 2 wk.
    
                                                            Time to analysis: Immediately following
                                                            exposure as well as 4 and 22 h post-exposure.
                                                                             No CAPs-induced respiratory symptoms
                                                                             observed in healthy older adults or older adults
                                                                             with COPD at 0, 4, or 22 h post-exposure.
                                                                             Exposure to CAPs did not significantly affect FVC
                                                                             or FEVi. CAPs exposure caused a decrease in
                                                                             arterial oxygen saturation immediately following
                                                                             exposure which was more pronounced in healthy
                                                                             older adults than in older adults with COPD.
                                                                             Exposure to CAPs was not observed to affect the
                                                                             levels of white blood cells, columnar epithelial
                                                                             cells, IL-6, or IL-8 in induced sputum.
    Reference: Gong et al.
    (2004, 0556281
    
    Subjects: 12 adult
    asthmatics, 4 healthy adults
    
    Gender: Asthmatic: 4 M/8 F,
    Healthy: 2 M/2 F
    
    Age: Asthmatic: avg 38 yr,
    Healthy: avg 32  yr
    Coarse CAPs (Los Angeles)
    
    Particle Size: 80% of mass
    between 2.5 and 10 pm, 20%
    of mass<2.5|jm
    
    Concentration: Mean:
    157 ug/m3; Range:
    56-218 ug/m3
                                                            Exposures to CAPs and filtered air (randomized
                                                            crossover) for 2 h with intermittent light exercise
                                                            (four15-min periods). Exposures were separated
                                                            by at least 2 wk.
    
                                                            Time to analysis: Immediately following
                                                            exposure as well as 4 and 22 h post-exposure.
                                                                             No effect of CAPs exposure on spirometry or
                                                                             arterial oxygen saturation was observed 0, 4, or
                                                                             22 h post-exposure. No respiratory symptoms
                                                                             reported 0-22 h post-exposure in either healthy or
                                                                             asthmatic adults.  Sputum cell counts at 22 h post-
                                                                             exposure did not  differ between CAPs and filtered
                                                                             air.
    December 2009
                                              C-10
    

    -------
            Reference
             Pollutant
                                                                             Exposure
                      Findings
    Reference: Gong et al.
    (2005, 0879211
    
    Subjects: 18 older adults with
    COPD, 6 healthy older adults
    
    Gender: COPD: 9 M/9 F,
    Healthy: 2 M/4 F
    
    Age: COPD: avg 72 yr,
    Healthy: avg 68 yr
    Fine CAPs (Los Angeles)
    
    Concentration: CAPs:
    200 pg/m3; N02: 0.4 ppm
                                                            Each subject was exposed to CAPs, N02, CAPs
                                                            + N02, and filtered air for 2 h with intermittent
                                                            exercise. Exposure order was not fully
                                                            counterbalanced as N02 exposures were
                                                            conducted after the majority of the CAPs and
                                                            filtered air exposures had been completed.
                                                            Exposures were separated by at least 2 wk.
    
                                                            Time to analysis: Immediately following
                                                            exposure as well as 4 and 22 h post-exposure.
    Exposure to CAPs was observed to decrease
    maximal mid-expiratory flow and arterial oxygen
    saturation relative to filtered air 4-22 h
    post-exposure. This response was more
    pronounced in healthy older adults than in older
    adults with COPD. Concomitant exposure to N02
    did not enhance the response. No other
    respiratory responses (symptoms, spirometry,
    sputum cell counts) were affected by exposure to
    CAPs.
    Reference: Gong et al.
    (2008, 1564831
    
    Subjects: 14 adult
    asthmatics, 17 healthy adults
    
    Gender: Asthmatics: 9 M/5 F,
    Healthy:5M/12F
    
    Age: Asthmatics: 34 + 12yr,
    Healthy:24 ± 8 yr
    Ultrafine CAPs (Los Angeles)
    
    Particle Number/Count:
    145,000/cm3, Range 39,000-
    312,000/cm3
    
    Concentration: Mean:
    100 ug/m3, Range:
    13-277 ug/m3
                                                            Subjects exposed for 2 h during intermittent
                                                            exercise (15-min periods) to both CAPs and
                                                            filtered air in random order. The first 7 subjects
                                                            underwent whole body exposure, while the
                                                            remaining subjects were exposed through a
                                                            facemask. Facemask exposures had higher
                                                            particle counts but lower particle mass than
                                                            whole body exposures. Exposures were
                                                            separated by at least 2 wk.
    
                                                            Time to analysis: Immediately following
                                                            exposure as well as 4 and 22 h post-exposure.
    No significant differences in respiratory symptoms
    observed between filtered air and ultrafine CAPs
    exposures. Individuals exposed to higher particle
    counts tended to experience greater symptoms
    with CAPs than with filtered air. An ultrafine
    CAPs-induced decrease in arterial oxygen
    saturation (0.5%) was observed at 0, 4, and 22 h
    post-exposure. A decrease in FEVi (2%) was also
    observed 22  h post-exposure relative to filtered
    air. Responses were not significantly different
    between healthy and asthmatic adults. CAPs
    exposure was not observed to affect total sputum
    cell counts or cytokine levels. There were no
    differences in response observed between
    facemask and whole body exposures.
    Reference: Graff et al. (2009,  Coarse CAPs (Chapel Hill,
    1919811                     NC)
    
    Subjects: 14 healthy adults    Concentration: 89
                                ± 49.5 pg/m3 (estimated
    Gender: 8 M/6 F             jnnaied dose = 67% of
    Age: 20-34 yr                measured particle mass)
                                                            Subjects exposed for 2 h with intermittent
                                                            exercise (15-min periods) to coarse CAPs and
                                                            filtered air in a randomized crossover design.
                                                            Exposures were separated by at least 2 mos.
    
                                                            Time to analysis: 0-1 and 20 h post-exposure.
                                                                             Pulmonary function (FVC, FEVi, and carbon
                                                                             monoxide diffusing capacity) was not affected by
                                                                             exposure to coarse CAPs either immediately
                                                                             following exposure or 20 h post-exposure. A
                                                                             significant increase in percent PMNs (10.7%
                                                                             increase per 10 pg/m3 coarse CAPs) was
                                                                             observed in BAL fluid 20 h post-exposure.
                                                                             Percent monocytes in BL fluid were slightly
                                                                             decreased at 20 h post-exposure (2.0% decrease
                                                                             per 10 [jg/m CAPs;  p = 0.05). Total protein in
                                                                             BAL fluid was also observed to decrease
                                                                             following CAPs exposure (1.8% decrease per
                                                                             10 pg/m  CAPs). Markers of inflammation in BAL
                                                                             and  BL fluids including IL-6,  IL-8,  and PGE2 were
                                                                             not affected by exposure to coarse CAPs.
    Reference: Huang et al.
    (2003, 0873771
    
    Subjects: 38 healthy adults
    
    Gender: 36 M/2 F
    
    Age: Avg 26.2 + 0.7 yr
    Fine CAPs (Chapel Hill, NC)
    
    Concentration:
    23.1-311.1 pg/m3
                                                            Subjects exposed to CAPs (n = 30) or filtered air
                                                            (n = 8) for 2 h with intermittent exercise (subjects
                                                            did not serve as their own controls). Component
                                                            data of CAPs was available for 37 of the 38
                                                            subjects.
    
                                                            Time to analysis: 18 h after exposure.
    The increase in bronchoalveolar lavage fluid
    neutrophils observed by Ghio et al. (2000,
    0121401 following exposure to fine CAPs was
    shown to be associated with iron, selenium, and
    sulfate content of the CAPs.
    Reference: Kongerud et al.
    (2006, 1566561
    
    Subjects: 17 asthmatic
    adults, 46 healthy adults
    
    Gender: Asthmatics-
    6M/11 F,  Healthy-24 M/22 F
    
    Age: Asthmatics: avg 23 yr,
    Healthy: avg 26 yr
    DEP
    
    N 1ST 1650, heavy duty diesel
    engine
    
    Concentration: Untreated
    and treated with 0.1 ppm 03
    (48 h); 300 pg per nostril
                                                            DEP (with and without 03 pre-treatment) were
                                                            intranasally instilled, using the saline vehicle as
                                                            control. Subjects did not serve as their own
                                                            controls (not a crossover design).
    
                                                            Time to analysis: 4 and 96 h post-instillation.
    Exposure to DEP was not observed to alter
    markers of inflammation in nasal lavage fluid
    (e.g., cell counts, IL-8, IL-6) at 4 or 96 h
    post-instillation.
    Reference: Larsson et al.
    (2007, 0913751
    
    Subjects: 16 healthy adults
    
    Gender:  10 M/6 F
    
    Age: 19-59 yr
    Traffic particles (road tunnel)
    
    Particle Size: PM2 5, PM,0;
    PM25 mass constituted -36%
    ofPM10mass
    
    Particle Number/Count: 20-
    1,000 nm:  1.1 xioW, <
    100 nm: 0.85 xl05/cm3
    
    Concentration: PM25-
    46-81 pg/m3; PM10-
    130-206 pg/m3
                                                            Exposures were conducted for 2 h with
                                                            intermittent exercise in a room adjacent to a busy
                                                            road tunnel. Study used a randomized crossover
                                                            design with each subject also exposed to normal
                                                            air (control). Exposures were separated by
                                                            3-10wks. No exposures to filtered air were
                                                            conducted. Other traffic emissions measured:
                                                            NO (874 pg/m3), N02 (230 pg/m3), CO (5.8 pg/m3
                                                            reported, likely 5.8 mg/m3).
    
                                                            Time to analysis: 14 h post-exposure.
    An increase in bronchoalveolar lavage fluid cell
    number, lymphocytes, and alveolar macrophages
    were observed 14 h after road tunnel exposure
    relative to control. Traffic particulate exposure
    was not shown to effect cytokine or adhesion
    molecule expression in bronchial tissues.
    Respiratory symptoms were reported to increase
    during exposure to road tunnel air relative to
    pre-exposure symptom ratings. Exposure to road
    tunnel air was not shown to affect lung function.
    December 2009
                                              C-11
    

    -------
            Reference
             Pollutant
                     Exposure
                      Findings
    Reference: Mudway et al.
    (2004,180208)
    
    Subjects: 25 healthy adults
    
    Gender: 16 M/9 F
    
    Age: 19-42 yr
    DE
    
    Idling 1991 Volvo diesel
    engine (TD45, 4.5 L, 4
    cylinders, 680 rpm)
    
    Concentration: PM10
    100 pg/m3
    Subjects exposed to DE and filtered air for 2 h
    with intermittent exercise (15-min periods) in a
    randomized crossover design. Exposures were
    separated by at least 3 wk. Other diesel
    emissions measured: N02 (0.2 ppm), NO (0.6
    ppm), CO (1.7 ppm), total hydrocarbons (1.4
    ppm), formaldehyde (43.5 pg/m ).
    
    Time to analysis: 1 h after the start of exposure,
    immediately following exposure,  and 6 h  post-
    exposure.
    DE caused mild throat irritation in some subjects
    and a significant increase in airways resistance
    (Raw) during or immediately following exposure.
    No changes in FEVi or FVC were observed
    following exposure to diesel. Neutrophil numbers
    in the bronchial airways tended to increase
    following exposure to DE; however, this increase
    was highly variable between subjects and did not
    reach statistical significance. Exposure to DE did
    not affect levels of SOD or malondialdehyde in
    the airways. An increase in levels of ascorbate
    and GSH in nasal lavage fluid  was observed 6 h
    following exposure to DE.
    Reference: Pietropaoli et al.
    (2004, 1560251
    
    Subjects: 16 asthmatic
    adults, 40 healthy adults
    
    Gender: Asthmatic: 8 M/8 F,
    Healthy: 20 M/20 F
    
    Age: 18-40 yr
    Ultrafine EC
    
    Particle Size: CMD -25 nm
    
    Particle Number/Count:
    10|jg/m3:~2.0xl06/cm3;
    25|jg/m3:~7.0xl06/cm3;
    50|jg/m3:~10.8xl06/cm3
    
    Concentration: 10, 25, and
    50 pg/m3
    Study conducted using a randomized crossover
    design with 2-h exposures. Asthmatics (n = 16)
    exposed to filtered air and 10 pg/m3.12 healthy
    adults exposed to filtered air and 10 pg/m3 at
    rest; 12 healthy adults exposed to filtered air, 10
    and 25 pg/m3 with  intermittent exercise; 16
    healthy adults exposed to filtered air and
    50 pg/m with intermittent exercise. Exposures
    were conducted via mouthpiece.
    
    Time to analysis:  Immediately following
    exposure as well as 3.5, 21, and 45 h post-
    exposure.
    No PM-induced changes in eNO or cell counts,
    IL-6, or IL-8 in induced sputum were observed in
    any of the protocols 21 h following exposure.
    Ultrafine carbon was not observed to increase
    respiratory symptoms in any of the study
    protocols. Healthy adults experienced an Ultrafine
    PM-induced reduction in maximal mid-expiratory
    flow and CO diffusing capacity relative to filtered
    air 21 h following exposure.
    Reference: Pourazar et al.
    (2005, 0883051
    
    Subjects: 15 healthy adults
    
    Gender: 11 M/4 F
    
    Age: 21-28 yr
    DE
    
    Idling Volvo diesel engine
    
    Particle Number/Count: 4.3
    x106/cm3
    
    Concentration: PM10
    300 pg/m3
    Subjects exposed to DE and filtered air for 1 h
    with intermittent exercise (randomized crossover
    study design). Other diesel emissions measured:
    N02 (1.6 ppm), NO (4.5 ppm), CO (7.5 ppm),
    total hydrocarbons (4.3 ppm), formaldehyde
    (0.26 mg/m3).
    
    Time to analysis: 6 h post-exposure.
    Exposure to DE significantly increased nuclear
    translocation of NF-KB, AP-1, phosphorylated
    p38, and phosphorylated JNK in bronchial
    epithelium 6 h post-exposure.
    Reference: Pourazar et al.
    (2008, 1568841
    
    Subjects: 15 healthy adults
    
    Gender: 11 M/4 F
    
    Age: 21-28 yr
    DE
    
    Idling Volvo diesel engine
    
    Particle Number/Count: 4.3
    x106/cm3
    
    Concentration: PM10
    300 pg/m3
    Subjects exposed to DE and filtered air for 1 h
    with intermittent exercise (randomized crossover
    study design). Other diesel emissions measured:
    N02 (1.6 ppm), NO (4.5 ppm), CO (7.5 ppm),
    total hydrocarbons (4.3 ppm), formaldehyde
    (0.26 mg/m3).
    
    Time to analysis: 6 h post-exposure.
    Exposure to DE observed to enhance epidermal
    growth factor receptor (EGFR) expression in
    bronchial epithelium 6 h post-exposure.
    Reference: Riechelmann
    et al. (2004, 1801201
    
    Subjects: 30 healthy adults
    
    Gender: 11  M/19 F
    
    Age: 22-32  yr
    Urban dust
    
    NISTSRM1649a
    
    Concentration: 150,
    500 pg/m3
    Subjects exposed to both concentrations of
    urban dust (nose only exposure system) as well
    as filtered air for 3h at rest in a randomized
    crossover design. Exposures were separated by
    at least 1 wk.
    
    Time to analysis: 30  min, 8 h, and 24 h post-
    exposure.
    An increase in nasal secretion (nasal cytology) of
    IL-6 and IL-8 were observed 24 h after exposure
    to 500 pg/m3 urban  dust.
    Reference: Samet et al.
    (2007, 1569401
    
    Subjects: Ultrafine CAPs: 20
    healthy adults, Coarse CAPs:
    14 healthy adults
    
    Gender: Ultrafine CAPs:
    11 M/9 F,  Coarse CAPs:
    8M/6F
    
    Age: 18-35 yr
    CAPs (Chapel Hill, NC)
    
    Particle Size: Ultrafine:
    0.049 + 0.009 pm, Coarse:
    3.59 +0.58pm
    
    Concentration: Ultrafine:
    47.0 + 20.2 pg/m3, Coarse:
    89.0 ± 49.5 pg/m3
    Preliminary report comparing effects of controlled
    exposures to coarse, fine, and Ultrafine CAPs
    among healthy adults (3 separate studies). A
    randomized crossover design was used in
    evaluating effects of coarse CAPs (n=14) and
    Ultrafine CAPs (n=20) relative to filtered air
    following of 2-h exposures with intermittent
    exercise. Results compared with previous study
    of controlled exposure to fine CAPs (Chapel Hill,
    NC) where subjects did not serve as their own
    controls (Ghio et al., 2000, 0121401
    
    Time to analysis: 0-20 h post-exposure.
    As was shown with fine CAPs, exposure to
    coarse CAPs increased the percentage of
    neutrophils in bronchoalveolar lavage fluid 20 h
    following exposure. Unlike fine CAPs, coarse
    CAPs did not increase the percent of monocytes
    in bronchoalveolar lavage fluid. Ultrafine CAPs
    were not shown to affect any markers of
    pulmonary inflammation in bronchoalveolar
    lavage fluid 18 h after exposure. No
    CAPs-induced changes in  lung function were
    observed.
    Reference: Samet et al.
    (2009,1919131
    
    Subjects: 19 healthy adults
    
    Gender: 10 M/9 F
    
    Age: 18-35 yr
    Ultrafine CAPs (Chapel Hill,
    NC)
    
    Particle Size: < 0.16pm
    
    Particle Number/Count:
    120,662 ± 48,232
    particles/cm3
    
    Concentration: 49.8 +
    20 pg/m3
    Subjects exposed for 2 h with intermittent 15
    periods of exercise to UF CAPs and filtered air
    using a randomized crossover study design.
    
    Time to analysis: Immediately following
    exposure and 1 and 18 h post-exposure.
    No effect of UF CAPs observed on pulmonary
    function immediately following exposure or 18 h
    post-exposure. IL-8 in BAL fluid was observed to
    increase with UF CAPs 18 h post-exposure. UF
    CAPs was not shown to alter any other
    inflammatory markers in BAL fluid.
    December 2009
                                              C-12
    

    -------
            Reference
               Pollutant
                     Exposure
                      Findings
    Reference: Schaumann et al.
    (2004, 0879661
    
    Subjects: 12 healthy adults
    
    Gender: 4 M/8 F
    
    Age: Avg27±2.5yr
      FinePM
    
      Collected (filter) from
      industrialized and
      non-industrialized areas in
      Germany
    
      Concentration: 100 |jg per
      subject
    Bronchoscopic instillation of particles collected
    from both areas was conducted in contralateral
    lung segments for each subject.
    
    Time to analysis: 24 h post-instillation.
    Particles collected from the industrialized area
    (transition metal-rich) increased the percentage of
    monocytes and oxidant radical generation in
    bronchoalveolar lavage fluid 24 h after exposure
    compared with PM containing less metal.
    Reference: Stenfors et al.
    (2004, 1570091
    
    Subjects: 15 asthmatic
    adults, 25 healthy adults
    
    Gender: Asthmatic: 10 M/5 F,
    Healthy:! 6 M/9F
    
    Age: Asthmatic: 22-52 yr,
    Healthy:! 9-42 yr
      DE
    
      Volvo diesel engine
    
      Concentration: PM1t
      108 pg/m3
    Subjects were exposed for 2 h with intermittent
    exercise to DE and filtered air using a
    randomized crossover study design. Other diesel
    emissions measured: N02 (0.7 ppm).
    
    Time to analysis: 1 h after the start of exposure,
    immediately following exposure, and 6 h post-
    exposure.
    DE was observed to increase neutrophilia and
    IL-8 in bronchial lavage fluid among healthy
    subjects 6 h after exposure. Among asthmatic
    subjects, exposure to DE did not cause an
    increase in inflammatory markers. No diesel-
    induced change in pulmonary function was
    observed during or immediately following
    exposure.
    Reference: Tunnicliffe et al.
    (2003, 0887441
    
    Subjects: 12 asthmatic
    adults, 12 healthy adults
    
    Gender: Asthmatics: 7 M/5 F,
    Healthy: 5 M/7 F
    
    Age: Asthmatics: avg 35.7 yr,
    Healthy: avg 34.5 yr
      Aerosols of ammonium
      bisulfate and sulfuric acid
    
      Particle Size: HMD 0.3 pm
    
      Concentration: 200,
      2,000 pg/m3
    Subjects were exposed for 1 h at rest to
    ammonium bisulfate (low and high
    concentrations), sulfuric acid (low and high
    concentrations) and filtered air in a randomized
    crossover design. Exposures were separated by
    at least 2 wk and were conducted using a head
    dome exposure system.
    
    Time to analysis: Immediately following
    exposure as well as 5.5-6 h post-exposure.
    Neither ammonium bisulfate nor aerosolized
    sulfuric acid were observed to affect lung function
    or respiratory systems following exposures to 200
    or 2,000 pg/m3 among healthy or asthmatic
    adults. Exposures to ammonium bisulfate at both
    concentrations resulted in a significant increase in
    eNO in the asthmatic subjects.
    Table C- 3.     Central nervous system effects.
           Reference
              Pollutant
                     Exposure
                      Findings
    Reference: Cruts et al.
    (2008,156374)
    
    Subjects: 10 healthy
    adults
    
    Gender: M
    
    Age: 18-39yr
    DE
    
    Idling Volvo diesel engine
    (TD45,4.5 L, 4 cylinders, 680
    rpm)
    
    Particle Number/Count: 1.2
    x106/cm3
    
    Concentration: 300 ug/nr
    Subjects were exposed to DE and filtered air for
    1 h at rest in a randomized crossover study
    design. Exposures were separated by 2-4 days.
    Other diesel emissions measured: N02 (1.6 ppm),
    NO (4.5 ppm), CO (7.5 ppm), total hydrocarbons
    (4.3 ppm).
    
    Time to analysis: From onset of exposure until
    1 h post-exposure.
     Exposure to DE was observed to significantly
     increase the median power frequency (MPF) in
     the frontal cortex during exposure, as well as in
     the hour following the completion of the
     exposure.
    December 2009
                                               C-13
    

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                                       Annex C References
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    Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
    developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
    December 2009                                       C-14
    

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    Danielsen PH; Brauner EV; Barregard L; Sallsten G; Wallin M; Olinski R; Rozalski R; Moller P; Loft S. (2008).
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    Ghio AJ; Kim C; Devlin RB. (2000). Concentrated ambient air particles induce mild pulmonary inflammation in healthy
           human volunteers. Am J Respir Grit Care Med, 162: 981-988.  012140
    
    Gilliland FD; Li YF; Saxon A; Diaz-Sanchez D. (2004). Effect of glutathione-S-transferase Ml and PI  genotypes on
           xenobiotic enhancement of allergic responses: randomised, placebo-controlled crossover study. Lancet, 363: 119-
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    Gong H Jr; Linn WS; Clark KW; Anderson KR; Geller MD; Sioutas C. (2005). Respiratory responses to exposures with
           fine particulates and nitrogen dioxide in the elderly with and without COPD.  Inhal Toxicol, 17:  123-132. 087921
    
    Gong H Jr; Linn WS; Clark KW; Anderson KR; Sioutas C;  Alexis NE; Cascio WE; Devlin RB. (2008). Exposures of
           healthy and asthmatic volunteers to concentrated ambient ultrafine particles in Los Angeles. Inhal Toxicol, 20: 533-
           545. 156483
    
    Gong H Jr; Linn WS; Terrell SL; Anderson KR; Clark KW; Sioutas C; Cascio WE; Alexis N; Devlin RB. (2004).
           Exposures of elderly volunteers with and without chronic obstructive pulmonary disease (COPD) to concentrated
           ambient  fine particulate pollution. Inhal Toxicol, 16: 731-744. 087964
    
    Gong H Jr; Linn WS; Terrell SL; Clark KW; Geller MD; Anderson KR; Cascio WE;  Sioutas C. (2004). Altered heart-rate
           variability  in asthmatic and healthy volunteers exposed to concentrated ambient coarse particles. Inhal Toxicol, 16:
           335-343. 055628
    
    Graff D; Cascio  W; Rappold A; Zhou H; Huang Y; Devlin R. (2009). Exposure to concentrated coarse air pollution
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    Huang Y-CT; Ghio AJ; Stonehuerner J; McGee J; Carter JD; Grambow SC; Devlin RB. (2003). The role of soluble
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    Kongerud J; Madden MC; Hazucha M; Peden D. (2006). Nasal responses in asthmatic and nonasthmatic subjects following
           exposure to diesel exhaust particles. Inhal Toxicol, 18: 589-594. 156656
    
    Larsson B-M; Sehistedt M; Grunewald J; Skold CM; Lundin A; Blomberg A; Sandstrom T; Eklund A; Svartengren M.
           (2007). Road tunnel air pollution induces bronchoalveolar inflammation in healthy subjects. Eur Respir J, 29: 699-
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    Lucking A; Lundback M; Mills N; Faratian D; Barath S; Pourazar J; Cassee F; Donaldson K; Boon N; Badimon J;
           Sandstorm T; Blomberg A; Newby D. (2008). Diesel exhaust inhalation increases thrombus formation in man. Eur
           Heart J, 29: 3043-3051. 191993
    
    Lund AK; Lucero J; Lucas S; Madden MC; McDonald JD;  Seagrave JC; Knuckles TL; Campen MJ. (2009). Vehicular
           emissions induce vascular MMP-9 expression and activity associated with endothelin-1 mediated pathways.
           Arterioscler Thromb Vase Biol, 29: 511-517. 180257
    
    Lundback M; Mills NL; Lucking A; Barath S; Donaldson K; Newby DE; Sandstrom T; Blomberg A. (2009). Experimental
           exposure to diesel exhaust increases arterial stiffness in man. Part Fibre Toxicol, 6: 7. 191967
    December 2009                                       C-15
    

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    Mills NL; Robinson SD; Fokkens PH; Leseman DL; Miller MR; Anderson D; Freney EJ; Heal MR; Donovan RJ;
           Blomberg A; Sandstrom T; MacNee W; Boon NA; Donaldson K; Newby DE; Cassee FR. (2008). Exposure to
           concentrated ambient particles does not affect vascular function in patients with coronary heart disease. Environ
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    Mills NL; Tornqvist H; Gonzalez MC; Vink E; Robinson SD; Soderberg S; Boon NA; Donaldson K; Sandstrom T;
           Blomberg A; Newby DE. (2007). Ischemic and thrombotic effects of dilute diesel-exhaust inhalation in men with
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    Mills NL; Tornqvist H; Robinson SD; Gonzalez M; Darnley K; MacNee W; Boon NA; Donaldson K; Blomberg A;
           Sandstrom T; Newby DE. (2005). Diesel exhaust inhalation causes vascular dysfunction and impaired endogenous
           fibrinolysis. Circulation, 112: 3930-3936. 095757
    
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           Kelly F J. (2004). An in vitro and in vivo investigation of the effects of diesel exhaust on human airway lining fluid
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    December 2009                                        C-16
    

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    Shah AP; Pietropaoli AP; Frasier LM; Speers DM; Chalupa DC; Delehanty JM; Huang LS; Utell MJ; Frampton MW.
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    December 2009                                       C-17
    

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                    Annex  D.   Toxicological  Studies
    Table D-1.     Cardiovascular effects.
          Study
              Pollutant
                  Exposure
                   Effects
    Reference: Anselme et DE: monocylinder Diesel engine using
    al. (2007, 0970841     Euro 4 ELF 85A reference gasoline
                                   Route: Whole-body Inhalation
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: Adult
    
    Weight: 200-225g
    Particle Size: DE: 10-650 nm (85 nm
    mean mobility diameter)
                                                                                  ; Other
    Dose/Concentration: DE: 0.5 mg/m
    emissions measured: non-methane
    hydrocarbons (7.7 ppm), N02 (1.1 ppm), CO
    (4.3 ppm)
    
    Time to Analysis: Experiments started 3 mo
    after L coronary artery ligation. ECG started at
    tO and the DE exposure at t30 min for a 3-h
    period; ventricular premature beats (VPBs) and
    RMSSD calculated every 30 min during clean
    room air exhaust and PE periods. Early (1210-
    300 min) and late ((480-540  min) PE were
    analyzed.
    Immediate decrease in RMSSD was observed in
    both healthy and CHF rats PE. Immediate
    increase in VPBs observed in CHF rats only;
    which lasted 4-5 h after exposure ceased.
    Whereas HRV progressively returned to baseline
    values within 2.5 h post-exposure (PE), the
    proarrhythmic effect persisted as late as 5 h PE
    termination in CHF rats
    Reference: Bagate et   IPS and EHC-93 (PM): Urban Air
    al. (2004, 0556381     collected at the Health Effects Institute
                       Ottawa, Canada
    Species: Rat
                       Particle Size: EHC-93: 0.8-0.4 pm
    Gender: Male        (mean) (range: <3 pm)
    
    Strain: SH
    
    Age: 13-15 wk
                                   Route: IT Instillation
    
                                   Dose/Concentration: PM: 10 mg/kg; IPS- 350
                                   EU/animal
    
                                   Time to Analysis: Sacrificed 4 or 24 h post-
                                   instillation
                                         PM and IPS elicited a significant increase in
                                         receptor-dependent vasorelaxation of the aorta
                                         compared to saline-instilled rats.
    Reference: Bagate et
    al. (2004, 0556381
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 13-15 wk
    EHC-93 (PM), CB-V or CB-Fe, IPS     Route: Aortic Suspension Fluid
    Particle Size: EHC-93: 0.8-0.4 pm
    (mean) (range: <3 pm)
    Dose/Concentration: Cumulative
    concentrations of EHC-93, CB-V and CB-Fe
    (10,25,50,75, 100|jg/mL)
    
    CB 1.5-2.0 nm (mean) (range <5 pm)
    
    Time to Analysis: Immediately post-exposure
    of aortic rings to cumulative concentrations of
    EHC-93, CB-V, CB-Fe and IPS.
    CB-V particles induced more relaxation than CB-
    Fe particles or EHC-93 in a dose-dependent
    manner. PM and IPS had an acute transient
    effect on the receptor dependent vasorelaxation.
    PM and IPS attenuated ACh-elicited
    vasocontraction in denuded aortic rings (DARs).
      Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
      Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
      developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
    December  2009
                                             D-1
    

    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Bagate et
    al. (2004, 0556381
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 13-15 wk
    EHC-93 (PM): Urban Air collected at
    the Health Effects Institute Ottawa,
    Canada.
    
    EHC-93 filtrate (PMF)
    
    Zn2* and Cu2* particles (10,000 and
    845 pg PM respectively)
    
    Particle Size: PM: 4.6 pm (GSD = 3.2)
    Route: In Vitro
    
    Dose/Concentration: PM Suspensions: 10-100
    pg/mL; CuS04/ZnS041-100 pmol; Phe 2 pm;
    arbacol: 10pm
    
    Time to Analysis: Measured immediately after
    maximum response for each cumulative dose
    was achieved.
    PM-lnduced Contraction: No effect of
    suspension or filtrate seen on resting tension of
    aorta and SMRA.
    
    PM- and Metal-Induced Vasorelaxation:
    Cumulative concentrations (10-100 pg/mL) of PM
    suspension and its water soluble components
    (PMF) elicited dose-dependent relaxation in
    aorta. Relaxation induced by particle suspension
    was higher than relaxation induced by free
    filtrate. The difference was significant at 100
    pg/mL  In SMRA, vasorelaxation similar to aorta's
    was observed, and the activity of the particle sus-
    pension was stronger than the filtrate, with the
    difference being significant starting at 30 pg/mL
    Both Zn  and Cu  in sulfate salts (10-100 pmol)
    induced relaxation  in pre-contracted aortic rings,
    with Cu2* having a greater effect than Zn2* at the
    same concentration.  Ions didn't affect ACh
    relaxation.
    
    Effect of PM on a-Adrenergic Contraction:
    Phenylephrine-induced dose-response
    contraction, starting at 1pM with max at 100
    pmol. Pre-treatment of SMRA did not change the
    phenylephrine-induced contraction.
    Reference: Bagate et
    al. (2006, 0976081
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    andSH
    
    Age: 13-15 wk
    EHC-93 (PM)                       Route: In Vitro
    
    EHC-93 (Filtrate)                    Dose/Concentration: PM and PMF
       2t       2t                       Suspensions: 10-100 pg/mL; CuS04 or
    Cu  andZn  solutions               ZnS04:10-100|jmol; Phenylephrine: 2 pm;
    
    Particle Size: PM: 4.6 pm (GSD = 3.2) Carbacol: 10 ^m
                                       Time to Analysis: Responses evaluated at
                                       maximum of each dose-response.
                                               PM and its soluble components elicited
                                               endothelium-independent vasodilation in rat aorta
                                               rings. This response is a result of the activation of
                                               sGC since its inhibition by NS2028 practically
                                               eliminated relaxation. PM suspensions stimulated
                                               cGMP production in purified isolated sGC.
                                               Neither receptor nor their signaling pathways
                                               played a significant role in the direct relaxation by
                                               PM or metals. Vasodilation responses were
                                               significantly higher in SH than WKY control rats.
    Reference: Bagate et
    al. (2006, 0961571
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH/NHsd
    
    Age: 11-12 wk
    
    Weight: 250-350 g
    EHC-93 (PM): Urban Air collected at
    the Health Effects Institute Ottawa,
    Canada.
    
    EHC-93 (Filtrate),
    
    Zinc (in PM), IPS
    
    Particle Size: PM: 4.6 pm (GSD = 3.2)
    Route: IT Instillation
    
    Dose/Concentration: PM: 10 mg/kg; IPS: 350
    EU/animal (0.5 ml)
    
    Time to Analysis: 4 h post-exposure
    Effect of Pretreatment on Baseline
    Parameters of Isolated Perfused Heart: After
    PM exposure a slight increase of baseline coro-
    nary flow (CF) and heart rate (HR) was noted.  In
    contrast, a significant decrease of left developing
    ventricular pressure (LDVP) was observed in SH.
    IPS also elicited a non-significant decrease in
    LVDP
    
    Effect of Pretreatment and Ischemia on
    Cardiac Function: When SH rats were
    pretreated with PM or IPS the isolated heart had
    a reduced  ability to recover to baseline levels
    after occlusion, in comparison with saline treated
    rats. After occlusion was released  CF went back
    to baseline values. Saline and IPS treated  rats,
    showed a gradual decrease in CF noted during
    the reperfusion period. Isolated hearts from PM-
    exposed SH showed a complete restoration of
    CF and no gradual decrease. The increase of
    Zn2+ elicited a rapid decrease of LDVP and HR.
    The impairment of cardiac function measured by
    LDVP and HR started immediately upon Zn2+
    infusion and remained the same during the
    perfusion period (no Zn2+ was present in the
    perfusate).
    Reference: Bagate et
    al. (2006, 0961571
    
    Species: Rat
    
    Strain: H9c2 (EACC),
    cardiomyocyte cells
    EHC-93 (PM) Filtrate: Urban Air col-
    lected at the Health Effects Institute
    Ottawa,  Canada,
    
    ZnS04
    
    Particle Size: PM:4.6|jm
    (GSD = 3.2); Carbon Particles: 44 nm
    Route: In Vitro
    
    Dose/Concentration: PM: 1, 50,100 pg/mL;
    ZnS04: 50 pmol
    
    Time to Analysis: 30 min incubation
    Effect of EHC-93 filtrate on Ca2* Uptake in
    Cardiomyocytes: Both PMF and Zn * inhibited
    ATP or ionophore-stimulated Ca2* influx in
    cardiomyocytes.
    December 2009
                                                    D-2
    

    -------
           Study
                                      Pollutant
                    Exposure
                      Effects
    Reference: Bartoli et
    al. (2009, 1562561
    
    Species: Dog
    
    Gender: Female
    
    Strain: Mixed breed
    
    Age: 2-12 yr
    
    Weight:
    Average:  15.7 kg,
    Range: 13.6-18.2 kg
                          CAPs (Boston; Harvard Ambient
                          Particle Concentrator)
    
                          Particle Size: Diameter: 0.15-2.5 pm
    Route: Permanent Tracheostomy
    
    Dose/Concentration: Concentration range and
    mean: CAPs: 94.1-1557(358.1 ± 306.7) pg/m3,
    BC: 1.3-32(7.5 + 6.1) pg/m3, Particle count:
    3000-69300(18230+13.151) particles/cm3
    
    Time to Analysis: Preanesthetized.
    Tracheostomy. 5 h exposures separated by
    minimum 1wk. Prazosin administered in 8 of 13
    dogs 30-60 min before exposure. 55 exposure
    days.
    CAPs significantly increased SBP, DBP, mean
    arterial pressure, HR and rate-pressure product.
    Prazosin (a-adrenergic antagonist) decreased
    these CAPs-induced effects. CAPs mass, BC,
    particle number concentrations were positively
    and significantly associated with each of the
    cardiovascular parameters except for pulse
    pressure.
    Reference: Bartoli et
    al. (2009, 1799041
    
    Species: Dog
    
    Gender: Female
    
    Strain: Mixed breed
    
    Age: Adult
    
    Weight: 14-18 kg
                          CAPs (Boston; Harvard Ambient
                          Particle Concentration)
    
                          Particle Size: Diameter: Ł2.5 pm
    Route: Permanent Tracheostomy
    
    Dose/Concentration: Concentration range and
    mean: CAPs: 94.1-1556.8 (349 + 282.6) pg/m3,
    BC: 1.3-32 (7.5 + 5.6) pg/m3, Particle number:
    3000-69300 (20381 + 13075) particles/cm3
    
    Time to Analysis: Tracheostomy. Minimum 3
    wk recovery. Acclimatized. Exposed 5 h. 2 5
    min occlusions of LAD coronary artery
    separated by 20 min rest. Exposure days
    separated by 1wk minimum.
    During coronary artery occlusion, CAPs exposure
    reduced myocardial blood flow and increased
    coronary vascular resistance, SBP and DBP
    CAPs effects were greater in ischemic tissue
    than nonischemic.  Increases in CAPs mass,
    particle number and BC concentrations were
    significantly associated with decreased
    myocardial blood flow and increased coronary
    vascular resistance.
    Reference: Campen et  High Whole DE (HVVDE); Low Whole
    al. (2005, 0839771      DE (LWDE); High PM Filtered (HPMF);
                          Low PM Filtered (LPMF)
    Species: Mouse
                          Particle Size: NR
    Gender: Male
    
    Strain: C57BL/6J and
    Apo E"'"
    
    Age: 10-12 wk
                                                             Route: Whole-body Inhalation and Ex-vivo
                                                             Exposures (isolated, pressurized septal
                                                             coronary arteries)
    
                                                             Dose/Concentration: HWDE: PM = 3.6 mg/m3;
                                                             N0x=102ppm
    
                                                             LWDE: PM = 0.512 mg/m3; NOX = 19 ppm;
                                                             PM = 0.770 mg/m3; NOX= 105 ppm
    
                                                             LPMF: PM = 0.006 mg/m3; NOX = 26 ppm
    
                                                             Time to Analysis: Whole-body Exposures: DE
                                                             or PFDE for 6 h/day for 3 days, euthanized at
                                                             the end of last exposure.
    
                                                             Coronary Vessels Exposure: PSS bubbled
                                                             with DE to expose coronary vessels to the
                                                             soluble contents of DE. Analysis occurred
                                                             immediately post exposure.
                                               Whole-body Exposure on ApoE : During DE
                                               exposure, ApoE" mice HR consistently
                                               decreased during high concentration exposures,
                                               compared to the C57BL/6J strain.
    
                                               Coronary Vascular Effects on ApoE  : DE had
                                               no significant effects on the resting myogenic
                                               tone of isolated septal coronary arteries. Control
                                               coronary arteries showed constrictive responses
                                               to ET-1 and  dilatory responses to SNP. DE
                                               exposed PSS vessels responses to ET-1
                                               enhanced compared to control. SNP-induced
                                               dilation blunted in vessels resting in diesel-
                                               exposed saline.
    Reference: Campen et  DE: generated by either of two         Route: Whole-body exposure
    al.(2003, 0556261       Cummins (2000 model) 5.9-L ISB turbo
                          engines fueled by Number 2 Diesel     Dose/Concentration: 0, 30,100, 300,1000
                          Certification Fuel.                    M9/m
    Species: Rat
    
    Gender: Male and
    Female
    
    Strain: SH
    
    Age: 4 mo
                          Particle Size: 0.1-0.2 pm aerodynamic  Time to Analysis: 6 h/day for 7 days; ECG
                          diameter                            measurements taken 4 days post-exposure.
                                               HR: Significantly higher in exposed animals and
                                               not concentration-dependent. More substantial
                                               results seen in male rats.
    
                                               ECG: The PQ interval was significantly prolonged
                                               among exposed animals in a concentration-
                                               dependent manner.
    Reference: Campen et  Road dust from paved surfaces (Reno,  Route: Whole-body inhalation
    al. (2006, 0968791
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 10 wk
                          NV)
    
                          Gasoline engine emissions, containing
                          PM, NOX, COandHC
    
                          Particle Size: Road dust: 1.6 pm
                          (Standard Deviation 2.0)
    
                          Gasoline engine emissions: Average
                          particle diameter of 15 nm
    Dose/Concentration: Road dust: 0.5 and 3.5
    mg/m3
    
    Gasoline engine emissions: 5 to 60 pg/m3 (at
    dilutions of 10:1,15:1, and 90:1)
    
    Mean concentrations of PM: 61 pg/m3; NOX:
    18.8 ppm; CO: 80 ppm.
    
    Time to Analysis: 6 h/days for 3 days.
    Sacrificed 18 h post-exposure.
    ET-1: Gasoline exhaust significantly upregulated
    ET-1 in a dose-dependent manner. ET-1 in-
    creased levels in the PM filtered group and
    decreased in the low levels of road dust.
    
    ECG: HR consistently decreased from beginning
    to end of exposure in all groups. No significant
    HR effects on road dust or gasoline exposure
    was observed. No significant effects on P-wave,
    PQ-interval, QRS-interval, or QT-interval were
    observed in either treatment.
    
    T-wave: Mice exposed to whole gasoline exhaust
    displayed significant increases in T-wave
    morphology from the beginning of exposures; this
    effect was consistent on all exposure days.
    December 2009
                                                                         D-3
    

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           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Cascio et   UFPM: Ultra fine PM, EPA Chapel Hill,  Route: IT Instillation
    al. (1987, 0075831
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age:6-10wk
    NC
    
    Particle Size: O.1 pm
    Dose/Concentration: 100 |jg in 100 pi
    
    Time to Analysis: 24 h post-exposure (single
    exposure)
    UFPM exposure double the size of myocardial in-
    farction attendant to an episode of ischemia and
    reperfusion while increasing post ischemic
    oxidant stress. UFPM alters endothelium-
    dependent/independent regulation of systemic
    vascular tone; increases platelet number, plasma
    fibrinogen, and soluble P-selectin  levels; reduces
    bleeding time.
    Reference: Chang et   UfCB: Ultra fine carbon black Ferric
    al. (2007, 1557201
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 60 days
    sulfate Fe2(S04)3
    
    Nickel sulfate NiS04
    
    Particle Size: UfCB
    Route: IT Instillation
    
    Dose/Concentration: UfCB: 415 and 830 pg
    
    Ferric Sulfate: 105 and 210 pg
    
    Nickel Sulfate: 263 and 526 pg
    
    Combined UfCB and ferric sulfate: 830 pg UfCB
    + 105 pg ferric sulfate
    
    Combined UfCB with Nickel Sulfate: 830 pg
    UfCB + 263 pg Nickel Sulfate
    
    Time to Analysis: Single dose, radiotelemetry
    readings recorded for 72 h post- exposure.
    Both high/low-dose UfCB decreased ANN
    (normal-to-normal intervals) slightly around the
    30th h, concurrent increases of LnSDNN.
    LnRMSSD returned to baseline levels after small
    initial increases. Minor effects observed after low-
    dose Fe and Ni instillation; biphasic changes
    occurred after high-dose instillations.  Combined
    exposures of UfCB and either Fe or Ni resulted in
    HRV trends different from values estimated from
    individual-component effects.
    Reference: Chang et   CAPs: collected during a dust storm
    al. (2007,1557201      from Chung-Li, Taipei
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 10 wk
    Particle Size: PM25
    Route: Nose-only Inhalation
    
    Dose/Concentration: 315.55 pg/m3
    
    Time to Analysis: 6 h
                                                                                  A linear mixed-effects model revealed sigmoid
                                                                                  increases in HR and a sigmoid decrease of QAI
                                                                                  during exposure, after an initial incubation period.
    Reference: Chang et
    al. (2004, 0556371
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 60 days
    CAPs collected in Chung-Li, Taipei
    (spring and summer periods)
    
    Particle Size: PM25
    Route: Nose-only Inhalation
    
    Dose/Concentration: Spring exposure: 202.0 +
    68.8 pg/m ; Mean number concentration: 2.30 *
    105 particles/cm3 (range: 7.12 xio3 - 8.26 xio5)
    
    Summer exposure: 141.0 + 54.9 pg/m3; Mean
    number concentration: 2.78 xio5 particles/cm3
    (range: 7.76 xio3-8.87 xio5)
    
    Time to Analysis: 4 days of spring exposure
    and days of summer exposure for 5 h each
    exposure. Parameters measured throughout
    duration of exposures.
    During spring exposures, the maximum increase
    of heart rate (HR) and blood pressure (BP) were
    51.6 bpm and 8.5 mmHg respectively. The
    maximum decrease of QAI (measures cardiac
    contractility) noted at the same time was 1.6ms.
    Similar pattern was observed during summer
    exposure, however, the responses were less
    prominent.
    Reference: Chang, et   CAPs collected in Chung-Li, Taipei
    al. (2005, 0977761
       v	'      Particle Size: PM25 (0.1-2.5 pm)
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Weight: 200 g
                                       Route: Nose-only Inhalation
    
                                       Dose/Concentration: 202.0 + 68.8 pg/m3
    
                                       Time to Analysis: 5 h/days for 4 days
                                               During the inhalation stage, crude effects of both
                                               LnSDNN and LnRMSSD for exposure and
                                               control groups decreased from the baseline
                                               values. Immediately after the experiments,  both
                                               LnSDNN and LNRMSSD decreased due to
                                               stresses produced by release from the exposure
                                               system, then returned to the baseline values.
    Reference: Chauhan
    et al. (2005, 1557221
    SRM-1879(Si02)andSRM-154b
    (Ti02) from the NIST
    Tumor Cell Line: A549  EHC-93 from Ontario, Canada
    derived from alveolar
    type II epithelial cells
    (EHCsol, EHCinsol)
    
    Particle Size: EHC-93 median
    physical diameter: 0.4 pm; Ti02 and
    Si02 particle size distribution: 0.3-0.6
    pm
    Route: Cell Culture
    
    Dose/Concentration: 0,1, 4, and 8 mg EHC
    total equivalent per 5 mL
    
    Time to Analysis: Culture medium was
    removed from flasks and replaced w/ 5 mL of
    the particle suspension media. Plates were
    incubated for 24 h. After 24 h cell culture
    supernatants were collected and analyzed.
    The decreased expression of preproET-1 in A549
    cells suggests that epithelial cells may not be the
    source of higher pulmonary ET-1 spillover in the
    circulation measured in vivo in response to
    inhaled urban particles. However, higher levels
    ECE-1 in A549 post-exposure to particles sug-
    gests an increased ability to process bigET-1 into
    mature ET-1  peptide, while increased receptor
    expression implies responsiveness. The
    increased release of II-8 and VEGF by epithelial
    cells in response to particles could  possibly up
    regulate ET-1 production in the adjacent pulmo-
    nary capillary endothelial cells, with concomitant
    increased ET-1 spillover in the systemic
    circulation.
    December 2009
                                                    D-4
    

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           Study
                Pollutant
                    Exposure
                                                                 Effects
    Reference: Chen et al.  CAPs (NYU, NY)
    (2005, 0872181
    Species: Mouse
    
    Strain: C57 and ApoE"'"
                          Particle Size: PM25
                                       Route: Whole-body Inhalation
    
                                       Dose/Concentration: 19.7 pg/m3 average
                                       concentration over 5 mo (daily average expo-
                                       sure concentration was 110 pg/m3)
    
                                       Time to Analysis: 6 h/days, 5 days/wk, for 5
                                       mo. Parameters measured continuously
                                       throughout.
                                               Significant decreasing patterns of HR, body
                                               temperature, and physical activity for ApoE"'"
                                               mice, with nonsignificant changes for C57 mice.
                                               SDNN and RMSSD in the late afternoon and
                                               overnight for ApoE'" mice showed a gradual
                                               increase for the first 6 wk, a decline for about 12
                                               more weeks, and a slight turn upward at the end
                                               of the study period. For C57 mice, there were no
                                               chronic effect changes in SDNN or RNSSD in the
                                               late afternoon, and a slight increase after 6 wk for
                                               the overnight period.
    Reference: Chen and
    Nadziejkov(2005,
    087219)(Chen and
    Nadziejko, 2006,
    087219)
    
    Species: Mouse
    
    Strain: C57, ApoE"'"
    
    Age: 26-28 wk(C57),
    39-41 wk(ApoE"'"), and
    18-20wk(LDLr"'"[DK])
    CAPs (NYU, NY)
    
    Particle Size: PM25
    Route: Whole-body Inhalation
    
    Dose/Concentration: Mean exposure
    concentration: 110|jg/m3
    
    Time to Analysis: 6 h/days, 5 days/wk for up to [.' "r'f wc;c V VT °
    5mo. Sacrificed 3-6 days after last exposure     "Pld content AP°E
                                               All DK mice developed extensive lesions in the
                                               aortic sinus regions. In male DK mice, the lesion
                                               areas appeared to be  enhanced by CAPs
                                               exposure. Plaque cellularity was increased, but
                                                                                                  Ł        ,
                                                                                  prominent areas of severe atherosclerosis.
                                                                                  Quantitative measurements showed that CAPs
                                                                                  increased the percentage of aortic intimal surface
                                                                                  covered by grossly discernible atherosclerotic
                                                                                  lesion.
    Reference: Corey LM
    et al. (2006, 1563661
    (2006,166366)(Corev
    et al, 2006, 156366)
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 11-12 mo
    
    Weight: 32.84 g (avg)
    PM collected November- March
    between 1996-1999 (Seattle, WA)
    
    Silica (U.S. Silica Company, Berkeley
    Springs, WV)
    
    Particle Size: PM25
    Route: Nasal Instillation
    
    Dose/Concentration: PM: 1.5 mg/kg; Saline:
    50 ul; Silica:  Min-u-Sil 5 in 50 pi saline
    
    Time to Analysis: Mice monitored for 1 day
    baseline prior to and for 4 days following
    exposure.
                                               After an initial increase in both HR and activity in
                                               all groups, there was delayed bradycardia with no
                                               change in activity of the animals in the PM and
                                               silica exposed groups. In addition, with PM and
                                               silica exposure, there was a decrease in HRV
                                               parameters.
    Reference: Cozzi et al.
    (2006, 0913801
    
    Species: Mouse
    
    Strain: ICR
    
    Age:6-10wk
    Ultrafine PM (collected continuously
    over 7-day periods in Oct 2002 in
    Chapel Hill, NC)
    
    Particle Size: <150nm
    Route: IT Instillation
    
    Dose/Concentration: 100 pg of PM in vehicle
    
    Time to Analysis: 24 h post-exposure
                                               Ischemia-Reperfusion: PM exposure doubled
                                               the relative size of myocardial infarction com-
                                               pared with the vehicle control. No difference was
                                               observed in the percentage of the vehicle at the
                                               risk of ischemia. PM exposure increased the
                                               level of oxidative stress in the myocardium after I-
                                               R. The density of neutrophils in the reperfused
                                               myocardium was increased by PM exposure, but
                                               differences in the numbers of blood leukocytes,
                                               expression of adhesion molecules on circulating
                                               neutrophils, and activation state of circulating
                                               neutrophils, 24 h after PM exposure, could not be
                                               correlated to the increase I-R injury observed.
    
                                               Isolated Aortas: Aortas isolated from PM-
                                               exposed animals exhibited a reduced
                                               endothelium-dependent relaxation response to
                                               ACh.
    Reference: Dvonch JT  CAPs, Detroit, Ml
    et al. (2004, 0557411
              	Particle Size: PM25
    Species: Rat
    
    Gender: Male
    
    Strain: Brown Norway
                                       Route: Whole-body Inhalation
    
                                       Dose/Concentration: Average concentration
                                       354 pg/m3
    
                                       Time to Analysis: 8 h/days for 3 consecutive
                                       days; plasma samples collected 24 h post-
                                       exposure.
                                               Plasma concentrations of asymmetric
                                               dimethylarginine (ADMA) were significantly
                                               elevated in rats exposed to CAPs versus filtered
    December 2009
                                                    D-5
    

    -------
           Study
                Pollutant
                    Exposure
                                                                                                    Effects
    Reference: Elder et al.
    (2004, 0556421
    
    Species: Rat
    
    Gender: Male
    
    Strain: Fischer 344
    andSH
    
    Age: 23 mo (Fischer);
    11-14mo(SH)
    
    Weight: NR
    UFP - Ultrafine carbon particles;
    IPS (Sigma)
    
    Particle Size: UFP: 36 nm (median
    size)
                                        Route: Whole-body inhalation; intraperitoneal
                                        injection (ip) for saline and IPS
    
                                        Dose/Concentration: Particles: 150 pg/m3;
                                        IPS: 2 mg/kg bw
    
                                        Time to Analysis: Single 6-h exposure to
                                        particles. Sacrificed 24 h after ip IPS exposure.
                                               BAL Fluid Cells: Neither inhaled UFP nor ip IPS
                                               cause a significant increase in BAL fluid total
                                               cells or the percentage of neutrophils in either rat
                                               strain. No significant exposure-related alteration
                                               in total protein concentration or the activities of
                                               LDH and b-glucuronidase.
    
                                               Peripheral Blood: In both rat strains ip IPS
                                               induced significant increase in the number and
                                               percentage of circulating PMNs. When combined
                                               with inhaled UFP, PMNs decreased, significantly
                                               for F-344 rats. Plasma fibrinogen  increased with
                                               ip IPS in both rat strains with the magnitude of
                                               change greater in SH rats. UFP alone decreased
                                               plasma fibrinogen in SH rats. Combined UFP and
                                               IPS response was blunted, but significantly
                                               higher than controls. Hematocrit was not altered
                                               in either rat strain by any treatment.
    
                                               TAT Complexes: Wth all exposure groups
                                               averaged, plasma TAT complexes in SH rats
                                               were 6.5 times higher than in F-344 rats. IPS
                                               caused an overall increase in TAT complexes for
                                               F-344 rats that was further augmented by inhaled
                                               UFP. UFP alone decreased response. In SH rats,
                                               UFP alone significant increased response and
                                               IPS decreased response.
    
                                               ROS in  BAL Cells: In F-344 rats both UFP and
                                               IPS have independent and significant effects on
                                               DCFD oxidation. Effects were in opposite
                                               directions;  particles decreased ROS, IPS
                                               increased ROS.
    Reference: Finnerty et
    al. (2007, 1564341
    
    Species: Mouse
    
    Gender: Male
    
    Strain: C57BL/6
    
    Age: 9 wk
    
    Weight: 22-2 7g
    Coal Fly Ash (U.S. EPA), Analysis:
    (PM25 samples) low unburned carbon
    (0.53 wt%), moderate levels of
    transition metals,  including (in pg/g):
    Fe(30, 400), Mg (31, 200), Ti (6, 180),
    Mn (907), and V (108).
    
    Particle Size: 1.8 and 2.5pm
    Route: IT Instillation
    
    Dose/Concentration: PM: 200 pg; 200 pg
    PM+10 pg IPS; 200 pg PM+100 pg IPS
    
    Time to Analysis: 18 h after IT instillation
                                                                                   Plasma: TNF-a significantly increased in both
                                                                                   PM+LPS10 and PM+LPS100 treatments. For
                                                                                   plasma IL-6, all groups tended to rise with a
                                                                                   significant increase in the PM+LPS100 group.
    Reference: Floyd et al.
    (2009, 1903501
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 20 wk
    CAPs: PM2 5 concentrated from
    Tuxedo, NY (April-Sept 2003)
    
    Particle Size: NR
                                        Route: Whole-body Inhalation
    
                                        Dose/Concentration: Avg 120 pg/m3
                                        (n=6/group)
    
                                        Time to Analysis: 6 h/days x 5 days/wk x 5 mo
                                               Gene Expression: Microarry gene expression
                                               identified 395 genes downregulated and 216
                                               genes upregulated in the aortic plaques.
                                               Ontologic analysis identified a list of functional
                                                                                   cellular movement, cellular growth and
                                                                                   proliferation, hematological system development
                                                                                   and function, lipid metabolism, cardiovascular
                                                                                   system function, cellular assembly and
                                                                                   organization, and cell death.
    Reference: Folkmann
    et al. (2007, 0973441
    
    Species: Mouse
    
    Gender: Female
    
    Strain: Wld type and
    ApoE'-
    
    Age: 11-13 wk
    
    Weight: 21 g (avg)
    DEP: SRM2975 (particulate fraction of
    exhaust from a filtering system
    designed for diesel-powered forklifts).
    
    Particle Size: DEP: NR
    Route: Intraperitoneal linjection
    
    Dose/Concentration: 0, 50, 500, 5,000 pg
    DEP/kg
    
    Time to Analysis: 6 or 24 h post-ip injection
                                                                                   The expression of inducible nitric oxide synthase
                                                                                   (iNOS) mRNA was increased in the liver 6 h post-
                                                                                   ip injection. The level of oxidized  purine bases,
                                                                                   determined byformamidopyrimidine DNA
                                                                                   glycosylase sites increased significantly in the
                                                                                   liver after 24 h in mice injected w/ 50|jg/kg. There
                                                                                   was no indication of systemic inflammation
                                                                                   determined as the serum concentration of nitric
                                                                                   oxide and iNOS expression,  and  DNA damage
                                                                                   was not increased in the aorta.
    December 2009
                                                    D-6
    

    -------
           Study
                Pollutant
                                                      Exposure
                      Effects
    Reference: Furuyama
    et al. (2006, 0970561
    
    Species: Rat
    
    Cell Type: Heart Micro
    vessel Endothelial
    (RHMVE) Cells
    OE-DEP, OE-UFP (from Urawa,
    Saitama, Japan)
    
    OE = Organic Extracts
    
    Particle Size: NR
                                       Route: Cell Culture
    
                                       Dose/Concentration: 0, 5, 10, 25 pg/mLof
                                       OE-DEP or OE-UFP
    
                                       Time to Analysis: Exposed for 0, 6,12, 24, or
                                       36 h
    The cell monolayer exposed to 10 pg/mL OE-
    UFP produced a larger amount of HO-1 than
    cells exposed to 10 pg/mL OE-UFP. OE-DEP and
    OE-UFP exposure reduced PAI-1 production by
    the cells but did not affect the production of
    thrombomodulin, tissue-type PA, or urokinase-
    type PA. Increased PAI-1 synthesis in response
    to treatment with 1 ng/mLTNF-aor0.5ng/mL
    TGF-|31 was reduced by OE-DEP  exposure.
    Suppression of PAI-1 production by OE-DEP
    exposure was mediated through oxidative stress
    and was independent of HO-1 activity.
    Reference: Gerlofs-
    Nijland et al. (2009,
    1903531
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 12 wk
    
    Weight: 200-300 g
    PM (Prague, Czech Republic;          Route: IT Instillation
    Duisburg, Germany; Barcelona, Spain)
    (Prague and Barcelona coarse PM      Dose/Concentration: 7 mg /kg
    
                                       Time to Analysis: DTPA added to some PM
                                       samples preinstillation. Instilled with PM.
                                       Necropsy 24 h post-exposure.
                          organic extracts)
    Particle Size: Coarse: 2.5-10 pm,
    Fine: 0.2-2.5 pm
    Inflammation (LDH, protein, albumin), cytotoxicity
    (NAG, MPO, TNF-a), and fibrinogen were
    increased by PM, and were greatest in the
    coarse PM fraction. Metal-rich PM had greater
    inflammatory and cytotoxic effects, and increased
    fibrinogen and vWF and decreased ACE. PAH
    content influenced greater inflammation
    (including neutrophils), cytotoxicity, and
    fibrinogen. Generally, whole PM and coarse PM
    were more potent than organic extracts and fine
    PM, respectively.
    Reference: Gerlofs-
    Nijland et al. (2007,
    0978401
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH/NHsd
    
    Age: 13 wk
    
    Weight: 250-350 g
    PM samples collected from:
    1. MOB high traffic density
    2. HIA high traffic density
    3. ROM high traffic density
    4. DOR moderate traffic density
    5 MGH low traffic density
    6 LYC low traffic density
    
    Particle Size: Coarse: 2.5-10 pm;
    Fine: 0.1-2.5pm
                                       Route: IT Instillation
    
                                       Dose/Concentration: 3,10 mg/kg
    
                                       Time to Analysis: 24 h
    Hematology: Fibrinogen responses of SH rats
    increased significantly at the high dose of both
    fractions of all PM samples, except fine PM from
    DOR.
    
    Location-Related Differences: Coarse PM from
    LYC lowered fibrinogen values more than PM
    from location MOB, HIA, and MGH. Fine PM
    showed less differences among the various sites.
    Reference: Gerlofs-
    Nijland et al. (2005,
    0886521
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH/NHsd
    
    Age: 11-12 wk
    
    Weight: 250-350 g
    RTD: road tunnel dust (obtained from a  Route: IT Instillation
    Motorway tunnel in Hendrik-ldo-
    Ambacht, Netherlands)               Dose/Concentration: 0.3,1, 3,10 mg/kg;
                                       EHC-93:10 mg/kg
    EHC-93
    (Ottawa, Canada)                    Time to Analysis: 4, 24, 48 h
    
    Particle Size: Coarse: 2.5-10 pm; fine:
    0.1-2.5 pm
                                                                                 Hematology: No significant changes in plasma
                                                                                 for bigET-1 or von Willebrand factor were
                                                                                 observed. At the highest dose, fibrinogen levels
                                                                                 significantly increased at 24 and 4 h for both PM
                                                                                 types.
    Reference: Ghelfi et al.
    (2008, 1564681
    
    Species: Rat
    
    Strain: SD
    
    Age: Adult
    CAPs
    
    CPZ (Capsazepine) (Axxora LLC, San
    Diego, CA)
    
    Particle Size: PM25
                                       Route: CAPs: Whole-body Inhalation; CPZ: IP
                                       Injection or Aerosol
    
                                       Dose/Concentration: CAPs: mean mass
                                       concentration: 218 + 23 pg/m ;  CPZ: 10 mg/kg
                                       (ip), 500 pmol (aerosol)
    
                                       Time to Analysis: Experiment 1: CPZ ip or 20
                                       min aerosol pretreatment immediately prior to
                                       CAPs exposure. Single CAPs exposure for 5 h.
                                       Parameters measured immediately following
                                       exposure.
    
                                       Experiment 2: CPZ ip pretreatment prior to
                                       CAPs exposure. Exposed to CAPs for 5 h/day
                                       for 4 mo. Parameters measured throughout
                                       duration of experiment.
    CPZ (ip or aerosol) decreased CAPs-induced
    chemiluminescence (CL), lipid thiobarbituric acid
    reactive substances (TBARS), and edema in the
    heart, indicating that blocking TRP receptors,
    systemically or locally, decreases heart CL. CAPs
    exposure led to significant decreases in HR and
    in the length of QT, RT, Pdur and Tpe intervals.
    These changes were observed immediately upon
    exposure, and were maintained throughout the
    5-h period of CAPs inhalation. Changes in
    cardiac rhythm and ECG morphology were pre-
    vented by CPZ.
    December 2009
                                                   D-7
    

    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Gilmour et
    al. (2004, 0541751
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar
    ufCB (Printex 90 from Frankfurt,
    Germany)
    
    fCB(Huber990fromUK)
    
    Particle Size: ufCB:  114 nm (MMAD);
    fCB: 268 nm (MMAD).
    Route: Whole-body Inhalation
    
    Dose/Concentration: ufCB: 1.66 mg/m3; fCB:
    1.40mg/m3
    
    Time to Analysis: Single exposure for 7 h.
    Sacrificed and samples taken at 0,16, and 48 h
    post-exposure.
    Exposure to ultrafine, but not fine, CB particles
    was also associated with significant increases in
    the total number of blood leukocytes. Plasma
    fibrinogen factor VIII and vWFwere unaffected by
    particle treatments as was plasma Trolox
    equivalent antioxidant status.
    Reference: Gilmour et
    al. (2005, 0874101
    
    Species: Human
    
    Cell Types: Primary
    Human Monocyte
    Derived  Macrophages
    (MP); Human Umbilical
    Vein  Endothelial Cells
    (HUVEC);A549 cells;
    16HBE
    PM10: (Carbon Black from Degussa
    Ltd, Frankfurt, Germany)
    
    Particle Size: PM10
    Route: Cell Culture
    
    Dose/Concentration: PM10: 50 and 100 pg/mL
    
    Time to Analysis: 6 and 20 h
    The culture media from MPsand 16HBE cells but
    not A549 cells, exposed to PM10 had an
    enhanced ability to cause clotting. H202 also
    increased clotting activity. Apoptosis was
    significantly increased in MPs exposed to PM10
    and IPS as shown by annexin V binding. TF
    gene expression was enhanced in MPs exposed
    to PM10 and HUVEC tissue factor. tPA gene and
    protein expression were inhibited.
    Reference: Gilmour et
    al. (2006, 1564721
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 12-14 wk
    
    Weight: 280-340 g
    Zinc Sulfate
    
    (ZnS04 in saline solution)
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 131 pg/kg (2 pmol/kg)
    
    Time to Analysis: 1,4, 24, 48 h
    Zinc levels in plasma and tissue: At 1-24 h
    post-exposure, zinc plasma levels increased to
    nearly 20% above baseline.
    
    mRNA expression: Cardiac tissues demon-
    strated similar temporal increases in expressions
    of TF, PAI-1 and thrombomodulin mRNA,
    following pulmonary instillation of Zn.
    
    Cardiac histopathology: Mild and focal acute,
    myocardial lesions developed in a few Zn ex-
    posed rats.  No changes in fibrin deposition or
    troponin disappearance were observed. At 24
    and 48h PE to Zn, increases occurred in levels of
    systemic fibrinogen an the activated partial
    thromboplastin time.
    Reference: Gong et al.
    (2007, 0911551
    
    Species: Mouse
    
    Cell Type: Human
    Microvascular
    Endothelial Cells
    (HMEC)
    
    Strain: C57BL/6J
    
    Gender: Male
    
    Age: 2 mo
    Organic DEP extract: collected from
    exhaust in a 4JB1-type LD, 2.74 liter,
    4-cylinder Isuzu diesel engine
    (provided by Masaru Sagai, Tsukuba,
    Japan)
    
    ox-PAPC: (provided by Judith Berliner,
    UCLA, CA)
    
    In vivo validation: Ultrafine (ufp) and
    fine (fp)  particulate matter
    
    Particle Size: DEP <1 pm (diameter)
    Route: Cell culture; In vivo validation via
    Whole-body inhalation
    
    Dose/Concentration: ox-PAPC: 10, 20, and 40
    pg/mL; DEP: 5,15, and 25 pg/mL; DEP (5
    pg/mL)+ox-PAPC: 10 or 20 pg/mL
    
    In Vivo Validation: Ufp: 3.2 4x105/cm3; fp: 2.7
    x105/cm3
    
    In vivo validation: Ufp: <0.18|jm; fp: <2.5|jm
    
    Time to Analysis: 4 h
    
    In vivo validation: Exposed to CAPs for 5 h/day,
    3 days/wk for 8 wk. Sacrificed 24 h after last
    CAPs exposure.
    Gene-expression profiling showed that both DEP
    extract and ox-PAPC co-regulated a large
    number of genes. Network analysis to identify co-
    expressed gene modules, led to the discovery of
    three modules that were highly enriched in genes
    that were differentially regulated by the stimuli.
    These modules were also enriched in
    synergistically co-regulated genes and pathways
    relevant to vascular inflammation.
    
    In vivo validation: Results were validated by
    demonstrating that hypercholesterolemic mice
    exposed to ambient ultrafine particles inhibited
    significant upregulation of the module genes in
    the liver.
    December 2009
                                                    D-8
    

    -------
           Study
                Pollutant
                   Exposure
                                                                                                                        Effects
    Reference: Goto et al.
    (2004, 0881001
    
    Species: Rabbit
    
    Gender: Female
    
    Strains: New Zealand
    White
    
    Age: NR
    
    Weight: 2.3 kg
    EHC-93 (Ottawa, ON.Canada)
    
    CC: Coilloidal Carbon (obtained from
    Hamburg, Germany)
    
    Particle Size: EHC-93: PM,0; CC: <1
    pm
    Route: Intrabronchial Instillation
    
    Dose/Concentration: AMs incubated with
    EHC-93 or CC: 0.6 ml/kg
    
    EHC-93 alone: 1 ml (500 pg/ ml)
    
    CC alone: 1 ml (1%CC)
    
    Time to Analysis: WBC counts measured
    4-168 h after BrdU injection. Sacrificed /days
    post instillation.
                                                                                                       Lung Distribution of PMi0: PM-containing AMs
                                                                                                       were distributed diffusely. PM-containing AMs
                                                                                                       were more prevalent in the PM exposed animals.
                                                                                                       There was noAM-containing particle difference
                                                                                                       between the CC-exposed and EHC-93-exposed
                                                                                                       groups.
    
                                                                                                       Monocyte Release from Bone Marrow: EHC
                                                                                                       exposure increased WBC and band cell counts
                                                                                                       from 12 h after instillation.  Monocyte count was
                                                                                                       not affected. Labeled monocytes peaked more
                                                                                                       quickly after DEP exposure (12 vs 16 h for
                                                                                                       control). There was no observed change in BM
                                                                                                       monocyte pool.
    
                                                                                                       Cytokine Release: EHC stimulation increased
                                                                                                       the release of GM-CSF,  IL-6, IL-lp, TNF-a, IL-8
                                                                                                       and MCP-1. No effect on m-CSF and MIP-1p. CC
                                                                                                       particles induced increases in IL-6 and TNF-a;
                                                                                                       other cytokine levels did not differ from control.
    
                                                                                                       Supernatant Instillation: AM+EHC increased
                                                                                                       circulating WBC and band cell counts. Circulating
                                                                                                       monocyte counts were unaffected. AM+EHC
                                                                                                       showed a major increase in fraction and amount
                                                                                                       of monocyte released as well as faster clearance
                                                                                                       when compared to control. The BM monocyte
                                                                                                       pool was similar in all groups.
    
                                                                                                       Monocyte Transit Time Through BM: Exposure
                                                                                                       to EHC, CC only shortened the transit time of
                                                                                                       monocytes as compared to controls. AM+EHC
                                                                                                       also shortened monocyte transit time whereas
                                                                                                       AM+CC had a nonsignificant effect.
    Reference: Gottipolu
    et al. (2009, 1903601
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wstar Kyoto,
    SH
    
    Age: 14-16 wk
    
    Weight: NR
    DE (30-kW (40hp) 4-cylinder indirect    Route: Inhalation
    injection Deutz diesel engine) (02-
    20%, CO-1.3-4.8 ppm, NO- <2.5-5.9
    ppm, N02- <0.25-1.2ppm, S02" 0.2-0.3
    ppm, OC/EC-0.3+ 0.03)
    Dose/Concentration: Low: 507 + 4 pg/m3:
    High: 2201 + 14 pg/m3
    Particle Size: Number Median
    Diameter: Low- 83 + 2 nm, High- 88. 2
    nm; Volume Median Diameter: Low-
    207 +2 nm, High-225 +2 nm
                                       Time to Analysis: Exposed 4 h/days, 5
                                       days/wk, 4 wk. Necropsied 1day post-exposure.
                                                                                                       DE dose-dependently inhibited mitochondrial
                                                                                                       aconitase activity. DE caused 377 genes to be
                                                                                                       differentially expressed within WKY rats, most of
                                                                                                       which were downregulated, but none in SH rats.
                                                                                                       However, WKY rats had an expression pattern
                                                                                                       shift that mimicked baseline expression of SH
                                                                                                       rats without DE. These genes regulated
                                                                                                       compensatory response, matrix metabolism,
                                                                                                       mitochondrial function, and oxidative stress
                                                                                                       response.
    Reference: Graff etal.
    (2005, 0879561
    
    Species: Rat
    
    Cell Type: Ventricular
    Myocytes
    Zn;V
    
    Particle Size: NR
                                                             Route: Cell Culture
                                       Dose/Concentration: 0, 6.25,12.5, 25, or 50
                                       pm
                                               Beat Rate: There were statistically significant
                                               reductions in spontaneous beat rate 4 and 24 h
                                               post-exposure (greater reductions were observed
                                               with Zn).
    
    Time to Analysis: Toxicity: 24 h post- exposure  inflammation: Exposure to Zn or V (6.25-50 pm)
    Beat Rate- 0 5 1 2 4 and 24 h PE            for 6 h Produced significant increases in IL-6,  IL-
    Beat Rate. 0.5, 1 , 2, 4, and 24 h PE            ^ hegt shocR protein ^ gnd connexin 43
    
    PCR: 6 and 24 h PE
                                                                                                       Impulse Conduction: 24 h post-exposure, Zn
                                                                                                       induced significant changes in the gene ex-
                                                                                                       pression of Kv4.2 and KvQLt, a-1 subunit of L-
                                                                                                       type Ca channel, Cx43, IL-6, and IL-1a. V pro-
                                                                                                       duced a greater effect on Cx43 and affected only
                                                                                                       KvLQTl
    Reference: Gunnison
    and Chen (2005,
    0879561
    
    Species: Mouse
    
    Gender: Male
    
    Strain: F2 generation
    DK (ApoE'~, LDLr'l
    
    Age: 18-20 wk
                          CAPs (Tuxedo, NY)
    
                          Copollutants measured: 03 and N02.
    
                          Particle Size: 389 + 2 nm
                                       Route: Whole-body Inhalation
    
                                       Dose/Concentration: CAPs: 131 + 99 pg/m3
    
                                       (range 13-441 pg/m3)
    
                                       03:10 ppb
    
                                       N02: 4.4 ppb
    
                                       Time to Analysis: 6 h/days, 5 days/wk for
                                       approximately 4 mo. Tissue collection was
                                       performed 3-4 days after the last day of
                                       exposure.
                                              Gene Expression: In CAPs-exposed heart
                                              tissue, the expression of Limdl and Rex3 were
                                              the most consistently affected genes among the
                                              exposed mice. Limdl was down regulated by
                                              1.5-fold or greater from moderate baseline
                                              expression. Rex3 showed a relatively small
                                              increase in absolute expression.
    December 2009
                                                   D-9
    

    -------
           Study
                Pollutant
                    Exposure
                                                                                                    Effects
    Reference: Gurgueira
    et al. (2002, 0365351
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Weight: 250-300 g
    CAPs;
    Carbon Black (CB from Fisher
    Scientific, Pittsburgh, PA): C (85.9 ±
    0.2%); 0(13 + 0.2%); S (1.17 +
    0.02%)
    
    ROFA: obtained from an oil-fired power
    plant (Boston, MA)
    
    Particle Size: CAPs size range: 0.1-
    2.5 fjm;CB and ROFA (PM2.5)
    Route: Whole-body Inhalation
    
    Dose/Concentration: CAPs: average mass
    concentration: 300 + 60 pg/m3; ROFA: 1.7
    mg/m3;CB: 170|jg/m3
    
    Time to Analysis: CAPs: 1, 3, and 5 h; ROFA:
    30 min; CB: 5 h
                                                                                  Oxidative Stress: Rats breathing CAPs aerosols
                                                                                  for 5 h showed significant oxidative stress,
                                                                                  determined as in situ chemiluminescence (CL) in
                                                                                  the lung, heart, but not in the liver. ROFA also
                                                                                  triggered increases in oxidant levels but not
                                                                                  particle-free air or CB. Increases in CL showed
                                                                                  strong associations with the CAPs content of Fe,
                                                                                  Al, Si and Ti in the heart. The oxidant stress
                                                                                  imposed by 5 h exposure to CAPs was
                                                                                  associated with slight, but significant increases in
                                                                                  the lung and  heart water content, with increased
                                                                                  serum levels of lactate dehydrogenase, indicating
                                                                                  mild damage to tissues. CAPs inhalation also led
                                                                                  to tissue-specific increases in the activities of
                                                                                  SOD and catalase.
    Reference: Gursinsky
    etal. (1976. 0156071
    
    Species: Rat
    
    Cell Type: Fibroblasts
    isolated from adult
    male Wistar rats hearts
    Fly ash (TAF98)
    
    Particle Size: NR
    Route: In Vitro
    
    Dose/Concentration: TAF98: 0,1, 2 3,10, 25,
    50, 100, 200|jg/mL
    
    Time to Analysis: 0, 5,10, 30, 60,120 min
                                                                                  Brief treatment of fibroblasts with fly ash triggered
                                                                                  the immediate formation of ROS. Using
                                                                                  phosphospecific antibodies the activation of p38
                                                                                  MAP kinase, p44/42 MAP kinase (ERK1/2) and
                                                                                  p70S6 kinase. Prolonged incubation with fly ash
                                                                                  increased the expression of collagen 1 and TGF-
                                                                                  P1, but decreased mRNA levels of MMP9 and
                                                                                  TNF-a. Cell proliferation was inhibited at high
                                                                                  concentrations of fly ash. An increase in the level
                                                                                  of advanced glycation end product modification
                                                                                  of various cellular proteins was observed.
    Reference: Hansen et
    al. (2007, 0907031
    
    Species: Mouse
    
    Gender: Female
    
    Strain: ApoE"'" and
    C57BL/6J ApoE*'*
    
    Age: 11-13 wk
    DEP: SRM-2975 (NIST)
    
    Particle Size: DEP: 215 nm
    (geometric mean diameter)
    Route: Intraperitoneal Injection
    
    Dose/Concentration: DEP: 0, 0.5 and 5 mg/kg;
    Aorta segments incubated with 0,10 and 100
    pg DEP/mL
    
    Time to Analysis: Sacrificed 1 h after ip
    injection.
                                                                                  Exposure to 0.5 mg/kg DEP caused a decrease
                                                                                  in the endothelium-dependent Ach elicited
                                                                                  vasorelaxation in ApoE"'" mice, whereas the re-
                                                                                  sponse was enhanced in ApoE*'* mice. No
                                                                                  significant changes were observed after
                                                                                  administration of 5 mg/kg DEP. K* or
                                                                                  phenylephrine induced constriction was not af-
                                                                                  fected.
    Reference: Hansen et
    al. (2007, 0907031
    
    Species: Mouse
    
    Gender: Female
    
    Strain: ApoE"'" and
    C57BL/6J ApoE*'*
    
    Use: Aorta rings used
    for in-vitro studies
    DEP: SRM-2975 (NIST)
    
    Particle Size: DEP: 215 nm
    (geometric mean diameter)
    Route: Cell Culture
    
    Dose/Concentration: 0,10 and 100 |jg
    DEP/mL
    
    Time to Analysis: Basal tone measured at 5
    different points throughout experiment.
                                                                                  Exposure to 100 pg DEP/mL enhanced ACh-
                                                                                  induced relaxation and attenuated
                                                                                  phenylephrine-induced constriction.
                                                                                  Vasodilatation induced by sodium nitroprusside
                                                                                  was not affected by any DEP exposure.
    Reference: Harder et
    al. (2005, 0873711
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 12-15 wk
    Carbon UFPs ((generated by Electric
    Spark Generator GFG 1000; Palas,
    Karlsruhe, Germany)
    
    Particle Size: 37.6 + 0.7 nm (mean)
                                       Route: Whole-body Inhalation
    
                                       Dose/Concentration: 180 pg/m3
    
                                       Time to Analysis: Days 1-3: baseline reading,
    
                                       Day 4: exposure to UFPs or filtered air for 4 or
                                       24 h then sacrificed immediately following
                                       exposure period OR
    
                                       Sacrificed following 1-3 days recovery period.
                                               Cardiovascular Performance: Mild but
                                               consistent increase in HR, which was associated
                                               with a significant decrease in HR variability
                                               during exposure (particle-induced alteration of
                                               cardiac autonomic balance, mediated by a
                                               pulmonary receptor activation).
    
                                               Lung Inflammation and Acute-Phase Re-
                                               sponse: BALF revealed significant but low-grade
                                               pulmonary inflammation.
    
                                               Effects on Blood: There was no evidence of an
                                               inflammation-mediated increase in blood
                                               coagulability; no changes in  plasma fibrinogen or
                                               factor Vila.
    
                                               Pulmonary and Cardiac Histopathology: Spo-
                                               radic accumulation of particle-laden
                                               macrophages found in the alveolar region. No
                                               signs of cardiac inflammation or cardiomyopathy.
    
                                               mRNA Expression Levels: No significant
                                               changes in the  lung or heart.
    December 2009
                                                   D-10
    

    -------
           Study
                Pollutant
                   Exposure
                     Effects
    Reference: Hirano et    Organic Extracts of DEP (DEP) and    Route: Cells Culture
    al. (2003, 0973451       Organic Extracts of Ultra Fine Particles
    
    Species: Rat           (UFP)'
                          (Urawa City, Saitama, Japan)
    Cell Types: Heart
    Microvessel Endothelial  Particle Size: DEP and UFP: <2.0 pm
    Cells (RHMVE)
                                       Dose/Concentration: MAC effects on viability:
                                       DEP: 25 fjg/ml; UFP: 50 pg/ml
    
                                       mRNA levels for DEP and UFP: 0,1,3,10 pg/ml
                                       cell monolayer exposed to DEP and UFP:
                                       1,10,100 fjg/ml
    
                                       Time to Analysis: mRNA levels measured after
                                       6 h incubation with DEP or UFP.  Other
                                       parameters measured after 24 h.
                                              Cytotoxicity and Oxidative Stress: LC50
                                              values were 17 and 34 pg/mL for DEP and UFP
                                              respectively. The viability of DEP and UFP
                                              exposed cells was ameliorated by N-acetyl-L-
                                              cysteine (MAC).
    
                                              mRNA Levels: mRNA levels increased dose-
                                              dependently with DEP and HO-1 mRNA showed
                                              the most marked response to DEP. mRNA levels
                                              of antioxidant enzymes and heat shock protein
                                              72 (HSP72) in DEP-exposed cells were higher
                                              than UFP exposed cells at the same
                                              concentration. The transcription levels of HO-1
                                              and HSP72 in DEP and UFP-exposed cells were
                                              also reduced by NAC.
    Reference: Hwang et
    al. (2005, 0894541
    
    Species: Mouse
    
    Strain: C57 and ApoE"'"
    CAPs (Tuxedo, NY)
    
    Particle Size: 389 + 2 nm
    Route: Whole-body Inhalation
    
    Dose/Concentration: CAPs Range: 5-627
    pg/m3. Mean CAPs Concentration: 133|jg/m3.
    Mean Concentrations of 03 and N02 in CAPs:
    10 and 4.4 ppb respectively.
    
    Time to Analysis: 6 h/day, 5 days/wk for 5 mo.
    Long-term Analysis: Significant decreasing
    patterns of HR, body temperature, and physical
    activity in ApoE"'" mice. Nonsignificant changes
    for C57 mice. The chronic effect changes for
    ApoE" mice were maximal in the last three wk.
    
    Short-term Analysis: Dose-dependent relation-
    ship for HR variations in ApoE"'" mice.
    
    Heart Rate Fluctuation: HR fluctuations in
    ApoE"'" mice during the period of 3-6 h increased
    by 1.35 fold at the end of the exposure and
    during a 15 min period increases by 0.7 fold at
    the end of the exposure.
    Reference: Inoueetal.
    (2006,1901421
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6- 7 wk
    DEP (obtained from a 4Jb1-type light-
    duty, 4-cylinder, 2.74-L Isuzu diesel
    engine)
    
    Washed DEP (carbonaceous nuclei of
    DEP after extraction) and DEP-OC
    (organic chemicals in DEP extracted
    with CH2CI2); Washed DEP+LPS and
    DEP-OC+LPS
    
    Particle Size: PM25
    Route: IT Instillation
    
    Dose/Concentration: Washed DEP: 4 mg/kg.
    DEP-OC: 4 mg/kg. IPS: 2.5 mg/kg. Washed
    DEP+LPS and DEP-OC+LPS: respective addi-
    tions of LPS to each component prior-
    experimentation.
    
    Time to Analysis: Sacrificed 24 h post single
    dose instillation.
    Both DEP components exacerbated vascular
    permeability. The increased fibrinogen and E-
    selectin levels induced by LPS. This exacerbation
    was more prominent with washed DEP than with
    DEP-OC. Washed DEP+LPS significantly
    decreased protein Cand antithrombin-lll and
    elevated circulatory levels of IL-6, KC and LPs
    without significance.
    Reference: Inoue et al. DEP (derived from 4 cyl, 2. 74! light
    (2006, 0978151 duty diesel engine)
    Species: Mouse Particle Size: NR
    Gender: Male
    Strains: C3H/HeJ
    (TLR-4 point mutant)
    and C3H/HeN (Control)
    Route: IT Instillation
    Dose/Concentration: 12 mg/kg
    Time to Analysis: 24 h
    
    Hematology: DEP increased plasma fibrinogen
    in both strains but with a greater increase in the
    knockout mice than the wild type.
    
    Age: 6 wk
    Reference: Ito et al.
    (2008, 0968231
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wstar Kyoto
    (Specific pathogen-
    free)
    
    Age: 13-14 wk
    CAPs (f-PM), Yokohama City, Japan.
    
    Particle Size: 0.1-2.5pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: 0.6-1.5 mg/m3
    
    Time to Analysis: Three groups exposed to:
    (1) filtered air for 4 days, (2) filtered air for 3
    days and CAPs for 1 day or (3) CAPs for 4
    days. All groups exposed for a maximum of 4.5
    h/days for 4 consecutive days.
    mRNA Expression and Cardiovascular
    Function: In samples of heart tissue, the mRNA
    of cytochrome P450 (CYP) 1B1, heme
    oxygenase-1 (HO-1), and endothelin A (ETA)
    receptor were  up-regulated by CAPs; their levels
    were significantly correlated with the cumulative
    weight of CAPs in the exposure chamber. The
    up-regulation of ETA receptor mRNA was signifi-
    cantly correlated with the increase in HO-1
    mRNA and weakly with the increase in MBP
    December 2009
                                                   D-11
    

    -------
           Study
                Pollutant
                    Exposure
                                                                                                                            Effects
    Reference: Khandoga
    Aetal. (2004, 0879281
    
    Species: Mouse
    
    Gender: Female
    
    Strain: C57B1/6
    
    Age: 5-7 wk
                          UFPs: Ultra fine carbon black particles  Route: Aortic Infusion
                          (Printex 90)                                                   7          7
                                                              Dose/Concentration: 1 xi O7 and 5 xi o7 total
                          Particle Size: 14 nm diameter (60%
                          <100nm)
                                        particles infused
    
                                        300 m2/g surface area
    
                                        Time to Analysis: Single exposure, analysis
                                        2 h post-exposure
                                                Platelet Effects: Application of UFPs caused
                                                significantly enhanced platelet accumulation on
                                                endothelium of postsinusodal venules and
                                                sinusoids in healthy mice. UFP-induced platelet
                                                adhesion was not preceded by platelet rolling but
                                                was strongly associated with fibrin deposition and
                                                an increase in vWF expression on the endothelial
                                                surface.
    
                                                Inflammatory Effects: In contrast, inflammatory
                                                parameters such as the number of
                                                rolling/adherent leukocytes, P-selectin expres-
                                                sion/translocation, and the number of apoptotic
                                                cells were not elevated. UFPs did not affect
                                                sinusoidal perfusion and Kupffer cell function.
    Reference: Knuckles ROFA-L: Leachate
    et al. (2007, 1566521
    Particle Size: <0.2 pm
    Species: Rat
    Gender: Female
    (Pregnant, purchased
    atGD19)
    Strain SD
    Route: Cell Culture
    Dose/Concentration: 3.5 |jg/mL
    Time to Analysis: 1 h
    ROFA-L Induced Alterations to the RCM
    Transcriptosome: 38 genes were suppressed
    and 44 genes were induced PE. Genomic
    alterations in pathways related to IGF-1, VEGF,
    IL-2, PI3/AKT, CVD, and free radical scavenging
    were detected. Global gene expression was
    altered in a manner consistent with cardiac myo-
    cyte electrophysiological remodeling, cellular
    oxidative stress and apoptosis.
    Age: 60-90 days
    
    Weight: 300 g
    
    Use: RMCs were
    harvest from 1 day-old
    neonatal pups
                                                                                   ROFA-L Induced Alterations to the RCM
                                                                                   Transcription Factor Proteome: ROFA-L
                                                                                   altered the transcription factor proteome by sup-
                                                                                   pressing activity of 24 and activating 40 trans-
                                                                                   cription factors out of 149.
    Reference: Knuckles
    et al. (2008, 1919871
    
    Species: Mouse
    
    Gender: Male
    
    Strain: C57BL/6
    
    Age:8-10wk
    
    Weight: NR
    DE (single cylinder Yanmar diesel
    generator burning #2 certified diesel
    fuel (Chevron-Phillips, Borger, TX)
    under 100% load)
    
    Particle Size: PM25
    Route: Whole-body Inhalation. Ex Vivo.
    
    Dose/Concentration: In vivo: 350 ug/m3; Ex
    vivo: PM2 5 concentration 2-3 mg/m flow rate
    500 mL/min
    
    Time to Analysis: Exposed 4 h. Ex vivo
    assays.
                                                                                                         Veins: DE increased vascular reactivity to ET-1.
                                                                                                         Ex vivo exposed vessels had greater
                                                                                                         vasoconstriction. L-NAME (an arginine blocker)
                                                                                                         did not promote constriction in DE-exposed rats
                                                                                                         but did so in controls.
    
                                                                                                         Arteries:  DE did not significantly alter vascular
                                                                                                         reactivity.  Carbonyls or alkanes alone or with DE
                                                                                                         did not alter vasoconstriction.
    Reference: Kodavanti
    et al. (2008, 1559071
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 12-14 wk
    G1: saline (control); G2: Mount Saint
    Helen's ash (SH); G3: whole suspen-
    sion of oil combustion PM at high
    concentration (PM-HD); G4: whole
    suspension of oil combustion PM at
    low concentration (PM-LD); G5: saline-
    leachable fraction of PM high-
    concentration suspension; G6:  zinc
    sulfate
    
    Particle Size: PM25
    Route: IT Instillation
    
    Dose/Concentration: Doses (mg/kg/wk) are for
    8 and 16 wk (PM-solid and soluble Zn)
    respectively. G1: 0.00-0.00 and 0.00-0.00;  G2:
    4.60-0.00 and 2.30-0.00; G3: 4.60-66.8 and
    2.30-33.4; G4: 2.30-33.4 and 1.15-16.7; G5:
    0.00-66.8 and 0.00-33.4; G6: 0.00-66.8 and
    0.00-33.4
    
    Time to Analysis: 1 x/wk for 8 or 16 wk;
    analyzed 48 h after last instillation.
                                                                                                          DMA Damage (left ventricular tissue): All
                                                                                                          groups except MSH caused varying degrees of
                                                                                                          damage relative to control. Total cardiac
                                                                                                          aconitase activity was inhibited in rats receiving
                                                                                                          soluble Zn. Analysis of heart tissue revealed mo-
                                                                                                          dest changes in mRNA for genes involved in sig-
                                                                                                          naling, ion channels function, oxidative stress,
                                                                                                          mitochondria! fatty acid metabolism, and cell
                                                                                                          cycle regulation in Zn, but not MSH-exposed rats.
    Reference: Kooter et
    al. (2006, 0975471
    Species: Rat
    Gender: Male
    Strain: SH
    Ana- •]r) '^A u/l/
    Age. IZ- 14 WK
    
    
    CAP-F = fine (Site 1)
    CAP-UF = fine + ultrafme (Site II)
    (Netherlands)
    Some measured components: Ammo-
    nium, nitrate, sulfate ions: 56 ± 16%
    CAP-F mass, 17 ± 6% CAP-UF mass
    Particle Size: 0.15
    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Kyoso et
    al. (2005, 1869981
    Species: Rat
    Gender: NR
    Strain: NR
    Age: 15 mo
    DE
    PM and NOX exposures
    Particle Size: NR
    Route: Whole-body Inhalation
    Dose/Concentration: PM (mg/m3): 0.01, 0.109,
    0.54, 1.09, 0.01 (from 1.09 concentration w/o
    PM)
    NOX (ppm): 0.19, 0.59, 2.60, 5.53, 5.47 (w/o
    PM)
    Time to Analysis: Exposed 16 h/days (from
    All of the resting R-R intervals before exposure
    were lower at night than during the day, but few
    changes were found after exposure.
                                                             5pm-9am) for 7 mo
    Reference: Lei et al.
    (2004, 0878841
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Weight: 300-350 g
    CAPs from Asian dust storm (Taiwan)   Route: Nose-only Inhalation
    Measured Components: Si, Al, S, Ca,
    K, Mg, Fe.As, Ni,W,V, OC, EC, S02,
    N02, nitrate, sulfate
    
    Particle Size: 0.01- 2.5pm
    Dose/Concentration: 315.6 pg/m3 (Low)
    or 684.5 pg/m3 (High)
    
    Time to Analysis: Low: Exposed for 6 h.
    Sacrificed 36 h post-exposure
    
    High: Exposed for 4.5 h. Sacrificed 36 h post-
    exposure
    
    Pulmonary hypertension induced 2 wk pre-
    exposure.
    Hematology: PM induced a dose-dependent
    increase in WBCs. No change was seen in
    RBCs. Platelet results were highly variable.
    Reference: Lei et al.
    (2005, 0886601
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Weight: 200-250 g
    
    Use: ip STZ (60 mg/kg)
    dissolved in citric acid
    buffer administered to 8
    rats to induce diabetes;
    ip citric acid buffer
    administered to 8 non-
    diabetic rats
    CAPs: Hsin-Chuang, Taipei
    
    Particle Size: PM: 0.01-2.5 pm
    Route: IT Instillation
    
    Dose/Concentration: PM25: 200 pg in 0.5 mL
    saline. Components (pg/m): (9.8-SD2.4)), EC
    (3.6-SD 3.2), Sulfate (4.8-SD 1.2), Nitrate (6.3-
    SD 3.4)
    
    Time to Analysis: Single dose. Animals
    sacrificed 24 h post instillation.
    Effects of Diabetes: Body weight (bw) of
    diabetic (D) rats (397.5 g) was lower than non-
    diabetic (ND) rats (483.1 g). Mean plasma
    glucose level was 163 mg/daysL in ND rats and
    448.2 mg/daysL in D rats. D rats had significant
    greater levels of 8-OHdG in plasma compared to
    ND rats.  D rats had significantly increased levels
    of plasma [nitrate+nitrite]. No observable
    changes in TNF-a for D and ND rats.
    
    Effects of PM Exposure ND Rats: Increase in
    plasma levels of 8-OHdG and plasma IL-6, TNF-
    a, and serum CRP Significant reduction of
    plasma [nitrate+nitrite]. No significant effect on
    plasma ET-1.
    
    Effects of PM Exposure STZ-D Rats:
    Significant elevation of plasma ET-1. Decrease in
    plasma [nitrate+nitrite] Plasma 8-OHdG and
    TNF-a significantly increased. No significant
    alterations in IL-6 and CRP.
    Reference: Lemos et
    al. (2006, 0885941
    
    Species: Mouse
    
    Gender: NR
    
    Strain: BALB/c
    
    Age: 1day (neonatal)
    
    n:10
    
    Weight: 4-6 g
    PM10, CO, N02, and S02 from
    Universidade de Sao Paulo, Brazil.
    
    Particle Size: PIvl-;
    Route: Whole-body Inhalation
    
    Dose/Concentration: Mean (+ SD)
    concentrations were: C02: 2.06 + 0.08 ppm (8h
    mean); N02:104.75 + 42.62 pg/m3 (24 h mean);
    S02:11.07 + 5.32 pg/m3 (24 h mean);
    PM,0: 35.52 +  12.84 pg/m3 (24 h mean)
    
    Time to Analysis: 24 h/days, 7 days/wk for 4
    mo
    Morphometric measurements of the ratio
    between the lumen and the wall (L/W) areas
    were performed on transverse sections of renal,
    pulmonary and coronary arteries. A significant
    decrease of L/W with exposure to air pollution
    was detected in pulmonary and coronary arteries,
    whereas no effects of air pollution were observed
    in renal vessels.
    Reference: Li et al.
    (2005, 0886471
    
    Species: Rat
    
    Strain: SD
    
    Tissues/Cell Types:
    Cultured HPAECs;
    Pulmonary Artery Rings
    (PARs)
    Urban Particles (UPsSRM 1648)
    
    Major Constituents (mass fraction in
    %):AI(3.4), Fe(3.9), K(1.1).
    
    Minor Constituents (mass fraction in
    %): Na (0.43), Pb (0.66), Zn (0.48).
    
    Trace Constituents (ng/mg): As (115),
    Cd (75), Cr (403), Cu (609), Mn (786),
    Ni (82), Se (27), U (5.5), V (127).
    
    Particle Size: NR
    Route: PARs: In vitro organ model HPAECs:
    grown to 80% confluence
    
    Dose/Concentration: PARs and HPAECs: 1 to
    100 pg/mL; Losartan treatment: 0.2 pmol
    Captopril treatment: 100 pmol
    
    Time to Analysis: PARs were exposed to
    increasing doses of UPs from 1 to 100 pg/mL
    Maximum tension was recorded within 5 min
    after each  UPs dose. HPAECs: exposed to UPs
    from 1 to 100 pg/mL for up to 2 min
    Effects of UPs on the constriction of isolated rat
    pulmonary PARs and the activation of
    extracellular signal-regulated kinases 1 and 2
    (ERK1/2) and p38 mitogen-activated protein
    kinases (MAPKs) in HPAECs with or without
    Losartan at 1-100 pg/mL induced acute
    vasoconstriction. UPs also produced a time- and
    dose-dependent increase in phosphorylation of
    ERK1/2 and p38 MAPK. Losartan pre-treatment
    inhibited both vasoconstriction and activation of
    ERK1/2 and p38. The water soluble fraction of
    UPs was sufficient for inducing ERK1/2 and p38
    phosphorylation, which was also inhibited by
    Losartan. Cu (CuS04) and V (VOS04), induced
    pulmonary vasoconstriction and phosphorylation
    of ERK1/2 and p38, but only phosphorylation of
    p38 was inhibited by Losartan. UPs induced
    activation of ERK1/2 and p38 was attenuated by
    Captopril.
    December 2009
                                                   D-13
    

    -------
           Study
                Pollutant
                    Exposure
                                                                                                                         Effects
    Reference: Li et al.
    (2006, 1566931
    
    Species: Rat, Rabbit,
    and Human
    
    Tissues/Cell Types:
    Pulmonary Artery Rings
    (PARs) (rat); isolated
    buffer-infused lungs
    (rabbits) and cultured
    HPAECs
    
    Strain: SD Rats, New
    Zealand White Rabbits
    
    Weight: Rat: 200-350
    g; Rabbit: 2.5-3.0 kg
    Urban Particles (UPsSRM 1648).
    
    Major Constituents (mass fraction in
    %):AI(3.4), Fe(3.9), K(1.1).
    
    Minor Constituents (mass fraction in
    %): Na (0.43), Pb (0.66), Zn (0.48).
    
    Trace Constituents (ng/mg): As (115),
    Cd (76), Cr (403), Cu (609), Mg (786),
    Ni (82), Se (27), U (5.5), V (127).
    
    Particle Size: NR
    Route: In Vitro
    
    Dose/Concentration: PARs and HPAECs: 1 to
    100 pg/mL
    
    Time to Analysis: PARs: treatment given 15
    min prior to exposure. Exposed to increasing
    doses of UPs from 1 to 100 pg/mL. Maximum
    tension was recorded within 5 min after each
    UPs dose. HPAECs: exposed to UPs from 1 to
    100|jg/mLfor20and120min.
                                                                                                        Effects of UP on H202 Release: Within minutes
                                                                                                        after UPs treatment, HPAEC increased H202
                                                                                                        production that could be inhibited by DPI, APO,
                                                                                                        and NaN3. The water soluble fraction of UPs as
                                                                                                        well as its two transition metal components Cu
                                                                                                        and V, also stimulated H202 production. NaN3
                                                                                                        inhibited H202 production stimulated by Cu and
                                                                                                        V, whereas DPI and APO inhibited only Cu-stimu-
                                                                                                        lated H202 production. Inhibitors of other H202-
                                                                                                        producing enzymes, including N-methyl-L-
                                                                                                        arginine, indomethacin, allopurinol, cimetidine,
                                                                                                        rotenone, and antimycin, had no effects.
    
                                                                                                        Effects of UP-induced H202 on MARK
                                                                                                        Activation: DPI but not NaN3  attenuated UPs-
                                                                                                        induced pulmonary vasoconstriction and
                                                                                                        phosphorylation of ERK1/2 and p38 MAPKs.
                                                                                                        Knockdown of p47phox gene expression by
                                                                                                        small interfering RNA attenuated UPs-induced
                                                                                                        H202 production and phosphorylation of ERK1/2
                                                                                                        and p38 MAPKs.
    Reference: Lippmann
    et al. (2005, 0874531
    
    Species: Mouse
    
    Strain: C57 and ApoE"'"
    (March-September 2003). Chemical
    Composition: regional secondary
    sulfate (SS) characterized by high S,
    Si, and organic C; resuspended soil
    (RS) characterized by high
    concentrations of Ca, Fe, Al, and Si;
    RO-fired powered emissions of the
    Eastern U.S. identified by the presence
    ofV, Ni, and Se; and motor vehicle
    (MV) traffic and other sources.
    Contributors to Average Mass: SS
     56.1%), RS(11.7%), RO combustion
     1.4%), MV traffic and other sources
    (30.9%)
    
    Particle Size: PM25
    Route: Whole-body Inhalation
    
    Dose/Concentration: PM25 concentrated ten-
    fold, producing an average of 113 pg/m3
    
    Time to Analysis: 6 h/days, 5 days/wk for 5
    mo. Parameters measured daily: during
    exposure, the afternoon after exposure, and
    late at night
                                                                                                       Associations Between Sources and Short-
                                                                                                       term Heart Rate Changes: There were no
                                                                                                       significant associations between SS, RS, RO,
                                                                                                       and MV factors and HR in C57 mice at any of the
                                                                                                       three intervals. There were significant asso-
                                                                                                       ciations between PM2 5 and the RS source factor
                                                                                                       and decreases in HR for the ApoE"'" mice during
                                                                                                       the daily CAPs exposures but no associations
                                                                                                       with the other factors. There was no residual
                                                                                                       association of HR with PM2 5 or the RS factor
                                                                                                       later in the afternoon or late at night.  In the
                                                                                                       afternoon, there was a significant association
                                                                                                       between decreases in HR and the SS factor for
                                                                                                       the ApoE" mice that had not been present during
                                                                                                       exposure and did not persist into the night time
                                                                                                       period. MV traffic and others were not
                                                                                                       significantly associated with HR during any of
                                                                                                       these three time periods. For the C57 mice, there
                                                                                                       were no significant associations of HR with PM2 5
                                                                                                       or any of its components during any of the three
                                                                                                       daily time periods.
    
                                                                                                       Associations Between Sources and Short-
                                                                                                       term HRV Changes: Signal noise during
                                                                                                       exposures did not permit reliable analyses of
                                                                                                       HRV changes during the hours of CAP exposure.
    Reference: Lippmann   CAPs (Sterling Forest, spring-summer
    et al. (2005, 0874531    2003)
    Species: Mouse
    
    Gender: NR
    
    Strain: ApoE"'", ApoE"'"
    LDLr"'", C57BL/6
    
    Age: NR
    
    Weight: NR
    Particle Size: PM2
    Route: Inhalation
    
    Dose/Concentration: PM25 average
    concentration: 110 pg/m3, Long-term average:
    19.7 pg/m3
    
    Time to Analysis: Exposed 6 h/days, 5
    days/wk, 5 or 6 mo. Semicontinuous EKG
    recordings.
                                                                                                        HR increased in ApoE" mice but not C57 mice.
                                                                                                        HRF increased over the duration of the
                                                                                                        experiment. Atherosclerotic plaque deposits and
                                                                                                        coronary artery disease lesions occurred in both
                                                                                                        CAPs-exposed mice and controls, but invasive
                                                                                                        lesions were only present in CAPs-exposed
                                                                                                        mice. A gene affecting circadian rhythm was
                                                                                                        upregulated  in double knockout mice. CAPs
                                                                                                        activated NF-KB. No inflammation occurred in the
                                                                                                        pulmonary system.
    Reference: Lippman M  CAPs from Tuxedo, NY. Component of  Route: Whole-body Inhalation
    et al. (2006, 091165)    interest: Ni.
    Species: Mouse
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 6 wk
                          Particle Size: PM25
                                       Dose/Concentration: Average daily CAPs:
                                       85.6 pgr3: Average daily Ni: 43 ng/m3
    
                                       Time to Analysis: 6 h/day, 5 days/wk, for 6 mo
                                       (July 2004-January 2005). 10-sECG, HR,
                                       activity, and body temperature data were
                                       sampled every 5 min for the duration of the
                                       experiment.
                                               For the CAPs-exposed mice, on 14 days there
                                               were Ni peaks at approximately 175 ng/m  and
                                               usually low CAPs and V For those days back-
                                               trajectory analysis identified a remote Ni point
                                               source. ECG measurements on CAPs-exposed
                                               and sham-exposed mice showed Ni to be
                                               significantly associated with acute changes in HR
                                               and HRV.
    December 2009
                                                   D-14
    

    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Lund et al.
    (2007, 1257411
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 10 wk
    
    Use: Mice were placed
    on a high fat at the
    beginning of the
    exposure.
    Varying dilutions of gasoline emis-
    sions: (generated using two 1996
    model 4.3L General Motors V-6
    engines, fueled with conventional,
    unleaded, non-oxygenated gasoline,
    equipped with stock exhaust systems).
    
    Composition for Hi, Med, and Lo
    dilutions:
    
    PM, NOX, CO, and Total Hydrocarbons
    (THC)
    
    Particle Size: NR
    Route: Whole-body Inhalation
    
    Dose/Concentration: FA: PM (2 pg/m3), NOX
    (0 ppm), CO (0.1 ppm), HC (0.1 ppm);
    
    Low (1: 90 dilution of exhaust): PM (8 pg/m3),
    NOX (2 ppm), CO (9 ppm), HC (0.9 ppm);
    
    Mid (1: 20): PM (39 pg/m3), NOX (12  ppm), CO
    (50 ppm), HC (8.4 ppm);
    
    High (1:12): PM (61 pg/m3), N0x(19ppm), CO
    (80 ppm), HC(12ppm);
    
    High-filtered (1:12): PM (2 pg/m3), NOX (18
    ppm), CO (80 ppm), HC (12.7 ppm).
    
    Time to Analysis: 6 h/day, 7 days/wk for 7 wk.
    Mice were sacrificed within 16 h PE.  During the
    study period all animals concurrently exposed
    to the following: FA: 8 pg/m3 and 40 pg/m3; PM
    Whole Exhaust: 60 pg/m ; or Filtered Exhaust
    w/ gases matching the 60 pg/m3 concentration.
    Inhalation exposure to gasoline engine emissions
    resulted in increased aortic mRNA expression of
    matrix metalloproteinase-3 (MMP-3), MMP-7, and
    MMP-9, tissue inhibitor of MMP-2, ET-1 and HO-
    1 in ApoE"'" mice; increased aortic MMP-9 protein
    levels were confirmed through immunochemistry
    Elevated ROS were also observed in arteries
    from exposed animals, despite absence of
    plasma markers. Similar findings were also
    observed in the aortas ApoE" mice exposed to
    particle filtered atmosphere, implicating the
    gaseous components of the whole exhaust in
    mediating the expression of markers associated
    with vasculopathy.
    Reference: Lund et al.
    (2007, 1257411
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 10 wk
    
    Weight: NR
    GEE (conventional unleaded,
    nonoxygenated, nonreformulated
    gasoline- ChevronPhillips Specialty
    Fuels Division)
    
    Particle Size: 0.150 pm(MMAD)
    Route: Inhalation
    
    Dose/Concentration: PM: 60 pg/m3, N02: 2
    ppm, NO: 16 ppm, CO: 80 ppm, THC: 12.7 ppm
    
    Time to Analysis: Mice fed high-fat diet 30
    days before exposure. Exposed 6 h/day, 1 or 7
    days. Some groups dosed with Tempol or BQ-
    123. Killed within 18 h of last exposure.
    Aorta gelatinase activity increased with GEE
    exposure time. MMP-2/9 activity spread
    throughout the vasculature by day 7. 7 day GEE
    exposure significantly increased the aorta protein
    expression of MMP-9, MMP-2, TIMP-2, and
    plasma MMP-9. Generally, in GEE-exposed
    mice, Tempol decreased TBARS and vascular
    ET-1, and BQ-123 decreased vascular ROS, ET-
    1, MMP-9, and gelatinase activity.
    Reference: McQueen
    et al. (2007, 0962661
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wstar Kyoto
    
    Weight: 228-500 g
    DEP: SRM 2975 (NIST)
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 0.5 mL/rat of 1 mg/mL;
    1-2.2 mg/kg
    
    Time to Analysis: 6 h.
    
    Pre-exposure: Vagotomy (sectioning of vagus
    nerve) or atropine, 1 mg/kg i.p. administered 30
    min prior, 2 and 4 h post.
    Cardiovascular Response: Blood pressure and
    heart rate were unaffected. Average arterial 02
    increased after DEP, but not when compared for
    each animal. C02 and pH were not affected
    Reference: Medeiros
    et al. (2004, 0960121
    
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age: 60 days
    
    Weight: 20-30 g
    CP: Carbon particles
    
    PSA: ROFA (solid waste incinerator
    hospital Sao Paulo, Brazil)
    
    PSB: electric precipitator, steel plant,
    Brazil)
    
    PSA/PSB Characteristics: Generally,
    PSB had greater component
    concentrations than PSA: Br(100+x),
    Cr (3x), Fe (10+x), Mn (2x), Rb (60+x),
    Se (7x), Zn (4x). PMA>PMB: Ce (3x),
    Co (10+x), La(100x), Sb(15x),V
    (50x).
    
    Particle Size: CP: 1.7 + 2.5 pm
    (78%<2.5 fjm)
    
    PMA:1.2±2.2|jm(98%<2.5|jm)
    
    PMB:1.2±2.2|jm(98%<2.5|jm)
    Reference: Intranasal Instillation
    
    Dose/Concentration: CP: 10 pg/mouse;
    0.5mg/kg
    
    PSA: 0.1,1 or 10 pg/mouse; 0.005, 0.05, 0.5
    mg/kg
    
    PSB: 0.1,1 or 10 pg/mouse; 0.005, 0.05, 0.5
    mg/kg
    
    Time to Analysis: Single, 24 h
    Hematology: PSA and PSB decreased
    leukocyte count (all 3 doses) and platelet count
    (2 high doses). No effect on hemoglobin,
    erythrocytes and reticulocytes was observed.
    Fibrinogen levels increased for both PSB and
    PSA with PSB seeing a higher increase. None of
    the effects were dose-dependent.
    
    Bone Marrow: Erythroblasts increased for PSA
    at all dose levels and PSB at mid and high dose
    levels (high variability).
    December 2009
                                                   D-15
    

    -------
           Study
                Pollutant
                    Exposure
                                                                                                                          Effects
    Reference: Montiel-
    Davalosetal.(2007,
    1567781
    
    Species: Human
    
    Cell Types: HUVEC
    (from primary human
    endothelial cells) and
    U937 (human leukemia
    pro-monocytic) cell
    cultures.
    PM25 and PMi0 from Mexico City
    
    Particle Size: PM25, PM10
    Route: In Vitro
    
    Dose/Concentration: HUVEC TNF-a (10
    ng/mLl, and a PM range of 5,10, 20, and 40
    pg/cm concentrations.
    
    Time to Analysis: 6 or 24 h (early and late
    adhesion molecules respectively)
                                                                                                         Results showed that both PM25 and PM10
                                                                                                         induced the adhesion of U937 cells to HUVEC,
                                                                                                         and their maximal effect was observed at 20
                                                                                                         pg/cm . This adhesion was associated with an in-
                                                                                                         crease in the expression of all adhesion
                                                                                                         molecules evaluated for PM10, and E-selectin, P-
                                                                                                         selectin, and ICAM-1 for PM25. In general the
                                                                                                         maximum expression of adhesion molecules in-
                                                                                                         duced by PM25 and PM10 was obtained with 20
                                                                                                         pg/cm ; however PMio-induced expression was
                                                                                                         observed from 5 pg/cm2. E-selectin and ICAM-1
                                                                                                         had the strongest expression  in response to
                                                                                                         particles.
    Reference: Moyer et    In phosphide (InP), Co sulfate hep-      Route: Inhalation
    al. (2002, 0522221
    
    Species: Mouse
    
    Gender: Male and
    Female
    
    Strain: B6C3F1
    tahydrate (CoS04 7H20), Vanadium
    pentoxide(V205) Gallium arsenide
    (GaAs), Ni oxide (NiO), Ni subsulfide
     Ni3S2), Ni sulfate hexahydrate
     NiS04 • 6H20), talc, and  Mo trioxide
    (Mo03)
    
    Particle Size: MMAD particle size
    (pm): InP (1.1-1.3), CoS047H20 (IS-
    IS), V205: (1.0), GaAs: (1.0)
    Dose/Concentration: High-Dose Con-
    centration in Chronic Studies, Male (pg/m ):
    InP: 0.3, CoS047H20: 3.0, V205: 4.0, GaAs:
    1.0
    
    High-Dose Concentration in Sub-Chronic
    Studies, Male or Female (pg/m3): InP: 100,
    CoS047H20: 30, V205:16, GaAs: 75
    
    Time to Analysis: Phase One: Evaluation of
    heart, kidney and lung tissues from all control
    and high dose male B6C3F1 mice exposed by
    inhalation to 9 particulate compounds for a 2yr
    period. Phase Two: evaluated heart, lung,
    kidney and mesentery tissues of control and
    high dose male and female B6C3F1 mice from
    the 90-day studies of the 4-compounds demon-
    strating arteritis after a 2-yr period.
                                                                                                         Phase One: High-dose males developed signifi-
                                                                                                         cantly increased incidences of arteritis over
                                                                                                         controls in 2 of the 9 studies (InP and CoS04
                                                                                                         7H20), while marginal increases of arteritis were
                                                                                                         detected in 2 additional studies (V205 and GaAs).
                                                                                                         In contrast, arteritis of the muscular arteries of
                                                                                                         the lung was not observed. Morphological
                                                                                                         features of arteritis in these studies included an
                                                                                                         influx of mixed inflammatory cells including
                                                                                                         neutrophils, lymphocytes, and macrophages.
                                                                                                         Partial and complete effacement of the normal
                                                                                                         vascular wall architecture, often with the exten-
                                                                                                         sion of the inflammatory process into the
                                                                                                         periarterial connective tissue, was observed.
    
                                                                                                         Phase Two: Results showed that arteritis did  not
                                                                                                         develop in the 90-day studies, suggesting that
                                                                                                         long-term chronic  exposure to lower-dose
                                                                                                         metallic PM may be necessary to induce or
                                                                                                         exacerbate arteritis.
    Reference: Mutlu et al.
    (2007,1214411
    
    Species: Mouse
    
    Gender: Male
    
    Strain: 57BL/6 (IL-6*'*
    and IL-ff'l
    
    Age: 6-8 wk
    
    Weight: 20-25 g
    PMio from ambient air in Dusseldorf,
    Germany
    
    Particle Size: PM10
    Route: IT Instillation
    
    Dose/Concentration: PMi0:10 pg; Clodronate:
    120mg
    
    Time to Analysis: For alveolar macrophage
    depletion, clodronate instilled into mice lungs
    following endotracheal intubation 48 h prior to
    instillation of PM. Parameters measured 24  h
    post-exposure.
                                                                                                         Mice treated with PMio exhibited a shortened
                                                                                                         bleeding time, decreased prothrombin and partial
                                                                                                         thromboplastin times (decreased plasma clothing
                                                                                                         times), increased levels of fibrinogen, and
                                                                                                         increased activity of factors II, VIII, and X. This
                                                                                                         prothrombotic tendency was associated with
                                                                                                         increased generation of intravascularthrombin,
                                                                                                         an acceleration of arterial thrombosis, and an
                                                                                                         increase in BALF concentration of prothrombotic
                                                                                                         IL-6. IL-6" mice were protected against PM-
                                                                                                         induced intravascular thrombin formation and the
                                                                                                         acceleration of arterial thrombosis. Depletion of
                                                                                                         macrophages by the IT administration of
                                                                                                         liposomal clodronate attenuated PM-induced IL-6
                                                                                                         production and the resultant prothrombotic
                                                                                                         tendency.
    Reference: Nadziejko
    et al. (2002, 0874601
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 16 wk
                          CAPs (PM25) from Tuxedo, NY. (S02,
                          N02 03 and NH3 were removed prior to
                          exposure).
    
                          H2S04 (fine and ultrafme)
    
                          Particle Size: Ultrafme H2S04 50-75
                          nm (MMAD)
                                        Route: Nose-only Inhalation
    
                                        Dose/Concentration: CAPs: 80 and 66 pg/m3
                                        (avg 73); Fine H2S04: 299, 280,119, and 203
                                        pg/m3 (avg 225); Ultrafme H2S04:140, 565,
                                        416, 750 pg/m3  (avg 468)
    
                                        Time to Analysis: 4 h/exposure
                                               Exposure to CAPs caused a striking decrease in
                                               respiratory rate that was apparent soon after the
                                               start of exposure and stopped when exposure to
                                               CAPs ceased. The decrease in respiratory rate
                                               was accompanied by a decrease in HR.
                                               Exposure of the same animals to fine-particle-
                                               size H2S04 aerosol also caused a significant
                                               decrease in respiratory rate similar to the effect of
                                               CAPs. Ultrafine  H2S04 had the opposite effect on
                                               respiratory rate compared to CAPs.
    Reference: Nadziejko
    et al. (2004, 0556321
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344
    
    Age: 18 mo
                          PM/CAPs (Tuxedo, NY)
    
                          UFC (lab generated)
    
                          S02
    
                          Particle Size: PM (Size Range): 0.5-
                          2.5pm; UFC (MMAD): 30-50 nm
                                        Route: Nose-only Inhalation
    
                                        Dose/Concentration: PM (pg/m3): 161-200,
                                        avg. 180; UFC (pg/m3): 500-1280, avg. 890;
                                        S02(ppm):1.2,1.2, avg. 1.2
    
                                        Time to Analysis: A total of 8 exposures were
                                        performed: 2 exposures to CAPs, 2 exposures
                                        to UFC, 4 exposures to S02. All three pollutants
                                        were tested w/ a crossover design so that each
                                        group alternated exposure to air and to
                                        pollutant. Exposures lasted 4 h and were
                                        performed at least 1wk apart. Parameters
                                        measured throughout duration of experiment.
                                               Old F344 rats had many spontaneous
                                               arrhythmias. There was a significant increase in
                                               the frequency of irregular and delayed beats after
                                               exposure to CAPs. The same rats were
                                               subsequently exposed to UFC, S02 or air with
                                               repeated crossover design. In these experiments
                                               there was no significant change in the frequency
                                               of any category of spontaneous arrhythmia
                                               following exposure to UFC or S02.
    December 2009
                                                    D-16
    

    -------
           Study
                                      Pollutant
                    Exposure
                      Effects
    Reference: Nemmar et  DEP (SRM 2975)
    al. (2008, 0965661
                          Particle Size: <1 |jm
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Weight: 440+14 g
                                                             Route: Intravenous via the tail vein
    
                                                             Dose/Concentration: DEP: 0.02mg orO.lmg
                                                             DEP/kg (corresponding to about 8 pg or 44 pg
                                                             DEP/rat)
    
                                                             Time to Analysis: 48 h following systemic
                                                             administration of saline or DEP
                                               Intravenous administration of DEP (0.1 mg/kg)
                                               triggered systemic inflammation characterized by
                                               an increase in monocyte an granulocyte
                                               numbers.  Both doses of DEP caused a reduction
                                               of RBC numbers and hemoglobin concentration.
                                               TEM analysis of RBCs after in vitro incubation (5
                                               pg/mL) or in vivo administration of DEP, revealed
                                               the presence of ultrafme-sized aggregates of
                                               DEP within the RBC. Larger aggregates were
                                               also taken up by the RBC. The myocardial mor-
                                               phology and capillary bed were  not affected by
                                               DEP exposure.
    Reference: Nemmar et  DEP (SRM 2975)
    ,.(2007,156800)      Partjc|e sjze: NR
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 16 wk
    
    Weight: 424 ± 8 g
                                                             Route: Tail Vein Injection
    
                                                             Dose/Concentration: 8, 42, or 212 pg DEP/rat
                                                             (150|jl of 0.02, 0.1, or 0.5 mg/kg)
    
                                                             Time to Analysis: 24 h
                                               Effect of DEP on Blood Pressure: Significant
                                               decrease on BP in DEP-exposed rats at doses of
                                               0.02 mg/kg, compared with mean BP  observed in
                                               controls.
    
                                               Effect of DEP on HR: Doses of 0.02,  0.1, and
                                               0.5 mg/kg in rats,  resulted in significant reduction
                                               of HR compared to controls.
    
                                               Effect of DEP on Tail Bleeding Time:
                                               Shortening of tail bleeding time in rats exposed to
                                               0.02, 0.1, and 0.5 mg/kg. The shortening was
                                               significant at the dose of 0.02 and 0.5 mg/kg
                                               compared w/ controls. Platelet counts in blood
                                               did not significantly increased post-DEP
                                               administration.
    
                                               Effect of DEP on WBC and RBC Numbers: No
                                               significant effect of DEP at doses of 0.02, 0.1  and
                                               0.5 mg/kg on the numbers of granulocytes,
                                               monocytes, or lymphocytes compared with
                                               control.
    Reference: Nemmar et  DEP (SRM 1650)
    al. (2003, 0965671
            	Particle Size: NR
    Species: Hamster
    
    Gender: Male and
    Female
    
    Weight: 100-110 g
                                                             Route: IT Instillation
    
                                                             Dose/Concentration: 120 \i\ (5, 50, or 500
                                                             pg/animal)
    
                                                             Time to Analysis: In-vivo: formation and
                                                             embolization of thrombus were continuously
                                                             monitored for 40 min. Ex-vivo: animals were
                                                             ITIy instilled w/ DEPs (0 or 50 pg per animal),
                                                             and blood was collected 5,15, 30, and 60 min
                                                             post-instillation. In-vitro: Saline or saline-
                                                             containing DEPs (0.1, 0.5,1, and 5 pg/mL) was
                                                             added to venous blood from untreated
                                                             hamsters, and closure time was measured in
                                                             thePFA-100after5min/animal.
                                               Doses of 5-500 pg enhanced experimental
                                               arterial and venous platelet-rich thrombus
                                               formation in-vivo. Blood samples taken from
                                               hamsters 30 and 60 min after instillation of 50 pg
                                               of DEPs yielded accelerated aperture closure
                                               (platelet activation) ex-vivo, when analyzed in the
                                               PFA-100. The direct addition of as little as 0.5
                                               pg/mL DEPs to untreated hamster blood
                                               significantly shortened closure time in vitro.
    Reference: Nemmar et  DEP (SRM 1650); Positively Charged
    al. (2004, 0879591      Polystyrene Particles (PCPSP)
    Species: Hamster
    
    Gender: Male and
    Female
    
    Weight: 100-110 g
                          Particle Size: PCPSP: 400 nm; DEP:
                          NR
    Route: IT Instillation
    
    Dose/Concentration: DEP: 50 pg/animal, or
    PCPSP: 500 pg/animal
    
    Time to Analysis: Pretreatment Phase:
    Hamsters were pretreated w/ Dexametasone IP
    (5 mg/kg) or IT (0.1  or 0.5 mg/kg) or Sodium
    Cromoglycate given IP (40 mg/kg), 1 h before
    DEP or vehicle instillation. Thrombosis: In-vivo
    thrombogenesis assessed 24 h post-instillation
    of DEP or vehicle.
    DEP increased thrombosis without elevating
    plasma vWF The IT instillation of PCPSP equally
    produced histamine release and enhanced
    thrombosis. Histamine in plasma resulted from
    basophil activation. IP pretreatment with
    Dexametasone abolished the DEP-induced
    histamine increase in BALF and plasma and
    abrogated airway inflammation and
    thrombogenicity The IT pretreatment with
    Dexametasone showed a partial but parallel
    inhibition of all these parameters. Pretreatment
    with Sodium Cromoglycate strongly inhibited
    thrombogenicity, and histamine release.
    Reference: Nemmar et  Ultrafine Particles: Unmodified
    al. (2003, 0974871      Polystyrene Particles (UPSPs); Nega-
                          tively Charged Carboxylate-Modified
    Species: Hamster      Polystyrene Particles (NCC-MPSPs);
                          Positively-Charged Amine Modified
                          Polystyrene Particles (PCA-MPSPs)
                                                             Route: IT Instillation                          Unmodified and negative UFPs did not modify
                                                                                                        thrombosis. Positive UFPs increased thrombosis
                                                             Dose/Concentration: 5, 50, and 500 pg/animal  at 500 and 50 pg/animal, but not at 5 pg/animal.
    Gender: Male and
    Female
    in 120 pi saline
    
    Time to Analysis: 1 h post-instillation
    Weight: 100-110 g
                          Particle Size: UPSPs: 60 nm; NCC-
                          MPSPs: 60 nm; PCA-MPSPs: 60 or
                          400 nm
    Positive 400 nm particles (500 pg/animal) did not
    affect thrombosis. PFA-100 analysis showed that
    platelets were activated by the in-vitro addition of
    positive UFPs and 400 nm particles to blood.
    December 2009
                                                                         D-17
    

    -------
           Study
                Pollutant
                                                                             Exposure
                      Effects
    Reference: Nemmar et  DEP (SRM 1650)
    al. (2003, 0879311
    Species: Hamster
    
    Weight: 100-110 g
                          Particle Size: NR
                                        Route: IT Instillation
    
                                        Dose/Concentration: 50 pg/animal in 120 |jl
                                        saline
    
                                        Time to Analysis: 1,  3, 6, and 24 h
                                                                                                         At 1, 6, and 24 h after instillation of 50 pg DEPs,
                                                                                                         the mean size of in-vivo induced and quantified
                                                                                                         venous thrombosis was increased by 480, 770,
                                                                                                         and 460%, respectively. Platelets activation in
                                                                                                         blood was confirmed by a shortened closure time
                                                                                                         in the PFA-100 analyzer. In plasma, histamine
                                                                                                         was increased only at 6 and 24 h. Pre-treatment
                                                                                                         with a H1 receptor antagonist (diphenhydramine,
                                                                                                         30 mg/kg intraperitoneally) did not affect DEP-
                                                                                                         induced thrombosis or platelet activation at 1  h;
                                                                                                         however both were markedly reduced at 6 and
                                                                                                         24 h.
    Reference: Niwa et al.
    (2007, 0913091
    
    Species: Mouse
    
    Gender: Male
    
    Strain: LDLr/KO
    
    Age,:6wk(n = 20)
    
    Use: IT CB dispersion;
    10-14 wk acute effect
    of CB dispersion on
    circulating  CRP
    Carbon Black
    
    Particle Size: 23-470 nm (mean size
    120.7 nm)
                                                              Route: IT Dispersion
    
                                                              Dose/Concentration: IT CB Dispersion Study:
                                                              1 mg per animal/wk; Acute Effect of CB
                                                              Dispersion on Circulating CRP Study:
                                                              1mg/animal (single administration)
    
                                                              Time to Analysis: IT CB Dispersion Study:
                                                              1x/wkfor 10wk
    
                                                              Acute Effect of CB Dispersion on Circulating
                                                              CRP Study: Single CB administration, blood
                                                              samples collected 24 h post-administration
    IT CB Dispersion Study: Although no difference
    in body weight (bw) between the four groups was
    observed at baseline, and all mice experienced
    an increase in bw with advancing age, the mice
    treated with CB tended to be smaller than those
    treated with vehicle (air). No significant
    differences were observed in cholesterol and TG
    levels among the for groups. Development of
    aortic lipid-rich lesions occurred in mice under a
    0.51 % cholesterol diet with or without CB
    infusion, but not in the mice fed a 0% cholesterol
    diet.
    
    Acute Effect of CB Dispersion on Circulating
    CRP Study: Circulating levels of CRP were
    significantly higher in mice exposed to CB versus
    those exposed to air, indicating an acute
    inflammatory response. Although the presence of
    CB in pulmonary macrophage-like cells in CB
    treated mice under 0.51% cholesterol diet was
    confirmed, CB was  not detected in aortas, livers,
    kidneys, or spleens.
    Reference: Niwa et al.
    (2007, 0913091
    
    Species: Mouse
    
    Cell Types: RAW264.7
    Carbon Black (CB); Water-Soluble
    Fullerene
    
    (C60(OH)24); Fluoresbrite Carboxylate
    Microspheres; Ox-LDL; Acetylated-LDL
    
    Particle Size: Carbon Black and
    C60(OH)24:7.1 nm(SD2.4);
    Fluoresbrite Carboxylate
    Microspheres: 6 nm
                                                              Route: Cell Culture
    
                                                              Dose/Concentration: CB: 1,10,100 pg/mL;
                                                              C6o(OH)24: 20,100ng/mL
    
                                                              Time to Analysis: RAW264.7+CB
    
                                                              for 24 h,  13 days, and 50 days;
    
                                                              RAW264.7+ C60(OH)24for 24 h or 10 days;
    
                                                              RAW264.7+ C60(OH)24for 8 days, then co-
                                                              treated w/ Ox-LDL for an additional 48 h;
    
                                                              RAW264.7+Ox-LDL for 5 days, and then co-
                                                              cultured w/ C60(OH)24 for an additional 48 h;
    
                                                              RAW264.7+ 6 nm beads: 3 days, the Ox-LDL or
                                                              acetylated-LDL added for 24 h
    CB alone had no significant effects on RAW264.7
    cell growth. C60(OH)24 alone or CB and C60(OH)24
    together w/ Ox-LDL induced cytotoxic
    morphological changes, such as Ox-LDL uptake-
    induced foam cell-like formation and decreased
    cell growth, in a dose-dependent manner.
    C60(OH)24 induced LOX-1  protein expression,
    pro-matrix metalloprotease-9 protein secretion,
    and tissue factor mRNA expression in lipid-laden
    macrophages. Although CB or C60(OH)24 alone
    did not induce platelet aggregation, C60(OH)24
    facilitated ADP-induced platelet aggregation.
    C60(OH)24 also acted as a competitive inhibitor of
    ADP receptor antagonists in ADP-mediated
    platelet aggregation.
    Reference: Niwa et al.  CB from Kyoto, Japan
    (2008, 1568121
    
    Species: Rat
    
    Strain: SD
    
    Age: 6 wk
                                                              Route: Whole-body Inhalation
                          Particle Size: Mean size (nm) + SD     Dose/Concentration: 15.6 + 3.5 mg/m3
                          determined at 1, 8,15, 22, and 29 day
                          post-exposure was 1181+24 1191+  Timeto Analysis: 6 h/day, 5 days/wk, for a
                                                                                   Although the presence of CB was confirmed in
                                                                                   pulmonary macrophages, electron microscopic
                                                                                   survey did not detect CB in other tissues
                                                                                   including, liver, spleen and aorta. CB exposure
    + 3.6 respectively
                                                              cuff plethysmography at 1,14,
                                                              -exposure. Sacrificed At 1, 7,14, 28, and 30
                                                              day post-exposure
                                                                                   inflammatory marker proteins, including
                                                                                   monocyte chemo attractant protein-1, IL-6, and
                                                                                   CRP, were higher in the CB treated groups than
                                                                                   in control groups.
    Reference: Nurkiewicz  ROFA (from Everett, MA). Major metal
    et al. (2004, 0879681    contaminants are: Fe, Al, V, Ni, Ca,
                          and Z. Main soluble metals are: Al, Ni,
    Species: Rat          and Ca.
    Gender: Male
    
    Strain: SD
    
    Age: 7-8 wk
    Particle Size: 2.2 pm (ROFA mean
    count diameter)
                                        Route: IT Instillation
    
                                        Dose/Concentration: ROFAgroup: 0.1, 0.25,
                                        1, or 2 mg/rat. Vehicle control group: 300 pi
                                        saline. Particle control group: Ti02 0.25 mg/rat.
                                                                                                         Saline Treated Rats: A23187 dilated arterioles
                                                                                                         up to 72 + 7% max.
    
                                                                                                         ROFA and Ti02 Exposed Rats: A23187-induced
                                                                                                         dilation was significantly attenuated.
                                                              Time to Analysis: After single IT instillation of a  Sensitivity of Arteriolar Smooth Muscle to
                                        particular dose, all rats recovered for 24 h.
                                                                                                         NO: Similar in saline treated and ROFA exposed
                                                                                                         rats.
    
                                                                                                         Other: Significant increase in venular leukocyte-
                                                                                                         adhesion and rolling observed in ROFA exposed
                                                                                                         rats.
    December 2009
                                                    D-18
    

    -------
           Study
                Pollutant
                    Exposure
                                                                                                                          Effects
    Reference: Nurkiewicz
    et al. (2006, 0886111
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 7-8 wk
                          ROFA from Everett, MA
    
                          Particle Size: ROFA mean count
                          diameter: 2.2 pm; Ti02 mean diameter:
                          1.0 pm
                                        Route: IT Instillation
    
                                        Dose/Concentration: ROFA group: 0.1 or 0.25
                                        mg/rat. Vehicle control group: 300 pi saline.
                                        Particle control group: Ti02 0.1 or 0.25 mg/rat.
    
                                        Time to Analysis: After single IT instillation of a
                                        particular dose, all rats recovered for 24 h.
                                               ROFA or TiO; Exposure and Arteriolar
                                               Dilation: Exposure caused a dose-dependent
                                               impairment of endothelium-dependent arteriolar
                                               dilation.
    
                                               ROFA or TiO Exposure and Arteriolar
                                               Constriction: Exposure did not affect
                                               microvascular constriction in response to PHE.
    
                                               ROFA and TiO  and Leukocyte Rolling and
                                               Adhesion: Exposure significantly increased
                                               leukocyte rolling and adhesion in aired venules,
                                               and these cells were identified as PMN
                                               leukocytes.
    
                                               ROFA and Ti02 and MPO: MPO was found in
                                               PMN leukocytes, adhering to the systemic mi-
                                               crovascular wall. Evidence suggests that some of
                                               this MPO had been deposited in the
                                               microvascular wall. There was also evidence of
                                               oxidative stress in the microvascular wall.
    Reference: Nurkiewicz  Ti02 (DeGussa, Sigma-Aldrich)
    et al. (2008, 1568161
                          Particle Size: Fine-1 pm, UF-21 nm
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 6-7wk
    
    Weight: NR
                                        Route: Whole-body Inhalation
    
                                        Dose/Concentration: Concentrations: Fine- 3-
                                        16 mg/m3; UF-1.5-12 mg/m3; Dose: Fine-8, 20,
                                        36, 67, 90|jg;UF-4, 6,  10, 19, 30|jg
    
                                        Time to Analysis: Acclimated 5 days. Exposed
                                        4-12 h. Sacrificed 24 h post-exposure.
                                               Particle accumulation within AMs, anuclear
                                               macrophages, particle-laden AMs intimately
                                               associated with the alveolar wall were all present
                                               in exposed rats. Calcium ionophore impaired
                                               arteriolar dilation in a dose-dependent manner in
                                               UF and fine exposed rats. UF produced greater
                                               systemic microvascular dysfunction.
                                               Microvascular dysfunction was the same for
                                               three groups of rats exposed to 30 pg UF Ti02
                                               under different conditions.
    Reference: Nurkiewicz
    et al. (2009, 1919611
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 7-8 wk
    
    Weight: NR
    Fine Ti02 (Sigma-Aldrich, St. Louis,
    MO) (-99% rutile)
    
    Ti02 nanoparticles (DeGussa-
    Aeroxide Ti02 P25, Parsippany, NJ)
    (80% anatase, 20% rutile)
    
    Particle Size: Fine Ti02- MMAD: 402
    nm, Primary size: <5 pm, ,CMD: 710
    nm; Nano-Ti02- MMAD:  138 nm,
    Primary size: 21  nm,, CMD: 100 nm
    Route: Aerosol Inhalation
    
    Dose/Concentration: 1.5-16mg/m3
    
    Time to Analysis: Acclimated 5 days. Exposed
    240-720 min. Anesthetized 24 h  post-exposure.
    Intravital microscopy, NO measurement,
    microvascular oxidative stress measurement,
    nitrotyrosine staining.
                                                                                                         Arteriolar Dilation: Nano-Ti02 significantly
                                                                                                         impaired endothelium-dependent arteriolar
                                                                                                         dilation. Equivalent levels of arteriolar dysfunction
                                                                                                         were found in fine and nano-Ti02. Arteriolar
                                                                                                         dilation in response to abluminal
                                                                                                         microiontophretic application of SNP was not
                                                                                                         different from the controls or between the
                                                                                                         exposure groups. Arteriolar dilation was partially
                                                                                                         restored  by radical scavenging with TEMPOL and
                                                                                                         catalase, NADPH oxidase with apocynin, and
                                                                                                         MPO inhibition with ABAH.
    
                                                                                                         Microcirculation: ROS increased in both
                                                                                                         groups. Nano-Ti02 significantly increased the
                                                                                                         area of tissue containing nitrotyrosine in the lung
                                                                                                         and spinotrapezius microcirculation.
    
                                                                                                         NO: Fine and nano-Ti02 significantly and dose-
                                                                                                         dependently decreased stimulated NO
                                                                                                         production in isolated microvessels. NO
                                                                                                         production was increased by radical scavenging
                                                                                                         with TEMPOL and catalase or NADPH oxidase
                                                                                                         with apocynin, and was largest in the fine Ti02
                                                                                                         group.
    December 2009
                                                    D-19
    

    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Okayama
    et al. (2006, 1568241
    
    Species: Rat
    
    Cell Type: Ventricular
    Cardiac Myocytes from
    Wistar Rats,
    approximately 3 days
    old
    DEP (Tsukuba, Japan)
    
    DEPE: 5g of DEP in 5 mL PBS
    containing 0.05% Tween 80.
    
    Others: Catalase, LDH,  MPG and
    SOD.
    
    Particle Size: DEP mass median
    diameter: 0.34 pm.
    Route: In Vitro
    
    Dose/Concentration: DEPE: 0-100 pg/mL;
    MPG: 0-1 mM; SOD: 800 U/mL; Catalase: 500
    U/mL
    
    Time to Analysis: cells were incubated for  1, 2,
    4, or 8, 24 or 48 h.
    
    LDH Activity of Supernatant: 24 h post-DEPE
    exposure.
    
    SOD, Catalase, MPG on DEPE-induced
    Toxicity: SOD, catalase or MPG was added  to
    cells w/ or w/o DEPE & incubated for 4 or 24 h.
    Medium then replaced w/serum-free & cells
    incubated for another 24 h to analysis.
    Cytotoxic Effects of DEPE on Cardiac
    Myocytes: DEPE above 20 pg/mL damaged
    cardiac myocytes in a time and concentration-
    dependent manner in both long- and short-term
    exposure conditions. However damage was
    greater after long-term exposure. LDH activity
    showed a concentration-dependent increase at
    higher levels of exposure (greater than 20
    |jg/mL).
    
    Effects of ROS Scavenging  Enzymes and
    Antioxidant on DEPE-induced Cell Damage:
    SOD or catalase attenuated 50 pg/mL DEPE-
    induced cell damage compared with DEPE-
    treated groups lacking antioxidant enzymes. Co-
    incubation with  SOD and catalase showed more
    protective effects towards DEPE-induced cell
    damage, although these effects were not
    statistically significant from cells treated with
    SOD only. MPG attenuated 50 pg/mL DEPE-
    induced cell damage in a concentration-
    dependent manner in both long and short-term
    exposure conditions. Especially in long-term
    exposure MPG  showed strong protective effects
    against DEPE-induced cell damage. Cell viability
    was not affected by SOD, catalase, or MPG.
    Reference: Proctor et
    al. (2006, 0884801
    
    Species: Rat
    
    Gender: Male
    
    Age: 12 wk
    
    Use: Thoracic Aorta
    from cp/cp and +/?
    Male Rats
    
    cp/cp = homozygous
    for cp gene. Prone to
    obesity and insulin
    resistant.
    
    +/? = heterozygous for
    either +/cp or +/+. Lean
    and metabolically
    normal.
    ROFA from Birmingham, AL
    
    Particle Size: 1.95 +0.18 fjm
    (aerodynamic diameter)
    Route: Protocol 1: Used two aorta rings per
    each experimental treatment group (4 groups
    total). Protocol 2: Used four rings.
    
    Dose/Concentration: Protocol 1: exposed to
    12.5 pg/mL ROFA-L (at  10 mg/mL).
    
    Protocol 2: exposed to 1.56, 3.25, 6.26,12.5
    pg/mL ROFA-L (at 10 mg/mL).
    
    Time to Analysis: Protocol 1: Cells treated with
    12.5 pg/mL ROFA-L and/or 104mol/L L-NAME
    for20min
    
    Protocol 2: Parameters measured after ROFA-L
    only treatment
    
    Contractile response to  phenylephrine (PE) was
    measured
    ROFA-L (12.5 pg/mL) increased PE-mediated
    contraction in obese, but not in lean rat aortae.
    Effect was exacerbated by L-NAME, and it
    reduced ACh-mediated relaxation in obese and
    lean aortae. Initial exposure of aortae to ROFA-L
    caused a  small contractile response, which was
    markedly  greater on second exposure in the
    obese aortae but marginal in lean.
    Reference: Radomski
    et al. (2005, 0913771
    
    Species: Rat
    
    Strain: Wistar Kyoto
    Carbon Nano Particles (CNPs)
    (purchased from SES Research,
    Houston, TX): Multiplewall Nanotubes
     MWNT); Single wall Nanotubes
     SWNT); C60 Fullerenes (C60CS);
    Mixed Carbon Nanoparticles (MCN)
    
    PM:(SRM1648)(NIST)
    
    Particle Size: CNPs: NR; PM: 1.4 pm
    average size
    Route: Simultaneous single PM injection into
    femoral vein as FeCI3 injected to induce carotid
    thrombosis
    
    Dose/Concentration: 0.5 mL suspension of 50
    |jg/mL of PM in 0.9% NaCI solution.
    
    Time to Analysis: Blood flow continuously
    monitored for 900 s.
    Vascular Thrombosis: FeCI3 induced carotid ar-
    tery thrombosis and MCN had an amplifying
    effect in the development of thrombosis.
    Infusions of MCN, SWNT, and MWNT signifi-
    cantly accelerated the time and rate of
    development of carotid artery thrombosis in rats.
    SRM1648 was less effective than CNPs in
    inducing thrombosis, while C60CS exerted no
    significant effect on the development of vascular
    thrombosis.
    Reference: Radomski
    et al. (2005, 0913771
    
    Species: Human
    
    Cell Types: Platelets
    
    Use: Human platelet
    aggregation
    Carbon Nano Particles (CNPs)
    (purchased from SES Research,
    Houston, TX): Multiplewall Nanotubes
    (MWNT); Singlewall Nanotubes
    (SWNT); C60 Fullerenes (C60CS);
    Mixed Carbon Nanoparticles (MCN);
    
    PM (SRM1648)
    
    Particle Size: CNPs: NR; PM: 1.4 pm
    average size
    Route: Cell Culture (2.5x108 platelets/mL)
    
    Dose/Concentration: CNPs: 0.2-300 pg/mL;
    PM: 5-300 pg/mL
    
    Time to Analysis: Prostacyclin (PGI2), S-ni-
    troso-glutathione (GSNO), aspirin, 2-methylthio-
    AMP, phenanthroline, EDTA and Go6976 were
    pre-incubated w/ platelets for 1 min before
    particle addition. Particles added to platelets
    and platelet aggregation studied for 8min.
    Platelet Aggregation: All CNPs, except C60CS,
    stimulated platelet aggregation (MCN 2
    SWNT>MWNT>SRM1648). All particles resulted
    in upregulation of GPIIb/llla in platelets.  In
    contrast, particles differentially affected the
    release of platelet granules, as well as the
    activity of thromboxane-, ADP, matrix
    metalloproteinase- and protein kinase C-de-
    pendent pathways of aggregation. Particle-
    induced aggregation was inhibited by
    prostacyclin and GSNO,  but not by aspirin.
    December 2009
                                                   D-20
    

    -------
           Study
                Pollutant
                   Exposure
                     Effects
    Reference: Reed et al.
    (2006, 1560431
    
    Species: Rat, Mouse
    
    Gender: Male and
    Female
    
    Strain: CDF
    (F344)/CrlBR (rat), SH
    (rat), A/J (mouse), and
    C57BL/6 (mouse)
    
    Age: 6-12 wk
    HWS (burned mix of hardwood in
    noncertified wood stove using a
    Pineridge model 27000, Heating and
    Energy Systems, Inc. Clackamas, OR)
    
    Measured Components: EC, OM, N03,
    S04, NH4, metals
    
    Particle Size: ~0.25 pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: Low: 30 pg/m3
    
    Mid-low: 100|jg/m3
    
    Mid-high: 300 pg/m3
    
    High: 1000 pg/m3
    
    Time to Analysis: 6 h/day, /days /wk for 1 wk
    or 6 mo. Immediate post-exposure analysis.
    Organ Weights: Liver declined in rats of both
    genders at 1 wk and female rats at 6 mo. Lung
    volume increased and lung weight decreased in
    female rats at 6 mo. Spleen weight increased in
    female mice and rats at 1wk. Thymus weight
    decreased in male rats at 1wk.
    
    Clinical Chemistry: Cholesterol decreased at
    the high dose for male rats at 1wk and 6 mo and
    increased at mid-low  and mid-high doses for
    female rats at 6 mo. ALP decreased for rats of
    both genders at 1wk and 6 mo for mid-low, mid-
    high and high dose levels (14-38%). AST
    decreased by 24% in male rats at Iwkwith high
    dose.  No effect on females. Creatinine serum
    levels decreased in males at 1wkat mid-high and
    high dose by 13%. No effect observed at 6 mo.
    BUN/Cre ratio  decreased in females at 1wk
    (25%) and both genders at 6 mo at mid-high and
    high dose (18-19%).
    
    Hematology: Hemoglobin and hematocrit
    increased in 6  mo male rats. Bilirubin increased
    in female rats at 6 mo at high dose. Platelets
    increased for male and female rats at 1wk (21%,
    19% respectively). No effect observed at 6m.
    WBC increased in males at 1wk.
    Reference: Reed et al.
    (2004, 0556251
    
    Species: Rat, Mouse
    
    Gender: Male and
    Female
    
    Strain: CDF
     F344)/CrlBR (rat), A/J
     mouse)
    
       e:12wk
    DE: generated from two 2000 model
    5.9 L Cummins ISM turbo diesel
    engines
    
    Co-exposure to 8 gas and 8 solid
    exhaust components measured
    
    Particle Size: 0.10-0.15pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: Low: 30 pg/m3
    
    Mid-low: 100|jg/m3
    
    Mid-high: 300 pg/m3
    
    High: 1000 pg/m3
    
    Time to Analysis: 6 h/day, 7 days/wk for 1wk
    or 6 mo. Analyzed 1  day post-exposure.
    Organ Weights: Kidney weight increased after
    6m for both males and female rats at the high
    dose.  Kidney and liver weight increased for
    female mice at all dose levels at 6 mo. Lung
    weight increased at high dose at 6mo for female
    mice and male rats. Spleen weight decreased in
    male mice  at the low and mid-high levels.
    
    Clinical  Chemistry: There was a massive
    decrease in cholesterol (24%) for rats of both
    genders after 1 wk and a smaller decrease for
    male rats at 6 mo. GGT significantly increased at
    6 mo for male and female rats at the mid-high
    and high dose. ALP increased in male rats at 1
    wk by  10%. AST decreased at mid-high (15%)
    and high dose in female rats at 6 mo. BUN and
    BUN/Creatine declined (19%, 17%) in female rats
    at mid-high and high doses after 6 mo. BUN
    increased by 21% at mid-low, mid-high and high
    doses in male rats at 1wk.
    
    Hematology: WBC decreased in high females
    after 6 mo.  Factor VII (blood clotting) decreased
    in MH  and  HR males after 1wk and male and
    female HR after 6 mo.  Thrombin-antithrombin
    complex declined massively but only in males
    after 1wk.
    Reference: Reed et al.
    (2008, 1569031
    
    Species: Rat
    
    Gender: Male, Female
    
    Strain: CDF
    (F344)/CrlBR, SH
    
    Age: NR
    
    Weight: NR
    GEE (two 1996 General Motors 4.3-L
    V-6 engines; regular, unleaded, non-
    oxygenated, non-reformulated
    Chevron-Phillips gasoline, U.S.
    average consumption for summer
    2001 and winter 2001-2002)
    
    Particle Size: 150 nm(MMAD)
    Route: Whole-body Inhalation
    
    Dose/Concentration: PM: Low- 6.6 + 3.7
    pg/m3, Medium-30.3 + 11.8|jg/m3, High-59.1 +
    28.3 pg/m3
    
    Time to Analysis: 2 wk quarantine period in
    chamber. Exposed 6 h/day, 7 days/wk, 3 day-6
    mo. SH- surgery to implant telemeter in
    peritoneal cavity. 4 wk recovery. ECG data
    obtained every 15 min beginning 3 day pre-
    exposure, 7 day exposure, 4 day post-
    exposure.
    Organ Weight: At 6 mo exposure, the heart
    weights of male and female rats increased and
    male rats' seminal vesicle weight decreased.
    
    Clinical Chemistry: Serum alanine
    aminotransferase, aspartate aminotransferase,
    and phosphorus decreased in medium and high-
    exposure females.
    
    Hematology: Hematocrit, red blood cell count,
    and hemoglobin dose-dependently increased for
    both genders at both time points. Plasma
    fibrinogen increased at 1wk in males.
    
    CV Effects in SH Rat: Lipid peroxides were
    significantly increased in  males in the high
    exposure group. TAT complexes decreased in
    females in the high exposure group.
    
    Removal of Emission PM: The removal of
    emission PM strongly linked PM to increased
    seminal vesicle weight, red blood cell counts,
    LDH, lipid peroxides, and methylation.
    December 2009
                                                   D-21
    

    -------
           Study
                Pollutant
                    Exposure
                                                                Effects
    Reference: Rhoden et
    al. (2005, 0878781
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: Adult
    
    Weight: 300 g
    Urban Ambient Particles (UAPs): SRM-  Route: UAPs: IT Instillation. CAPs: Inhalation
    1649; CAPs (Boston, MA)             „    ln     tt.    ,,,„,„
                                       Dose/Concentration: UAPs: 750 pg
    Particle Size: NR                    suspended in 300 pi saline; CAPs: 700 + 180
                                       pg/m3
    
                                       Time to Analysis: UAPs: 30 min post-instil-
                                       lation. CAPs: immediately after 5 h exposure
                                       period
                                               Oxidative Stress and HR Function: UAPs
                                               instillation led to significant increases in heart
                                               oxidants. HR increased immediately after
                                               exposure and returned to basal levels over the
                                               next 30 min. SDNN was unchanged immediately
                                               after exposure, but significantly increased during
                                               the recovery phase.
    
                                               Role of ROS in Cardiac Response: Rats were
                                               treated with 50 mg/kg MAC 1 h prior to UAPs in-
                                               stillation or CAPs inhalation. MAC prevented
                                               changes in heart rate and SDNN in UAPs-
                                               exposed rats.
    
                                               Role of the Autonomic Nervous System in
                                               PM-induced Oxidative Stress: Rats were given
                                               5 mg/kg atenolol, 0.30 mg/kg glycopyrrolate, or
                                               saline immediately before CAPs exposure. Both
                                               atenolol and glycopyrrolate effectively prevented
                                               CAPS-induced cardiac oxidative stress.
    Reference: Rivero et
    al. (2005, 0886531
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 3 mo
    
    Weight: -250 g
    PM2 5, collected from heavy traffic area
    in Sao Paulo, Brazil. PM25 Composi-
    tion (%): S (3.05), As (0.30), Br (0.21),
    Cl (2.09), Co (2.65), Fe (2.67), La
    (5.42), Mn (0.64), Sb (0.21), Sc (3.25),
    Th(8.14)
    
    Particle Size: PM25
    Route: IT Instillation
    
    Dose/Concentration: 100 or 500 pg of PM25.
    
    Time to Analysis: 24 h post-instillation
                                               Hematology: Total reticulocytes significantly
                                               increased at both PM25 doses, while hematocrit
                                               levels increased in the 500 pg group. Quan-
                                               tification of segmented neutrophils and fibrinogen
                                               levels showed a significant decrease, while
                                               lymphocytes counting increased with 100 pg of
                                               PM25.
    
                                               Pulmonary  Vasculature: Significant dose-de-
                                               pendent decrease of intra-acinar pulmonary
                                               arteriole lumen/wall ratio was observed in both
                                               PM25 groups.
    
                                               Wet-to Dry Weight Ratio: Significant increase in
                                               heart wet-to-dry weight ratio was observed  in the
                                               500 pg group.
    Reference: Rivero et
    al. (2005, 0886591
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 3 mo
    
    Weight: -250 g
    PM2 5, collected from heavy traffic area
    in Sao Paulo, Brazil. PM25 Composi-
    tion (%): S (3.05), As (0.30), Br (0.21),
    Cl (2.09), Co (2.65), Fe (2.67),
    La (5.42), Mn (0.64), Sb (0.21),
    Sc (3.25), Th (8.14)
    
    Particle Size: PM25
    Route: IT Instillation
    
    Dose/Concentration: 50 and 100 pg of PM25.
    
    Time to Analysis: HR and SDNN were
    assessed immediately b
    60 min post-instillation.
                                      < 3°and
                                               HR decreased significantly with time, but no
                                               significant effect of treatment or interaction
                                               between time and treatment was observed. In
                                               contrast, there was a significant SDNN
                                               interaction between time and treatment. The
                                               PM25 concentration of 50 and 100 pg.
    Reference: Seagrave
    et al. (2008, 1919901
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 10-12 wk
    
    Weight: 250-300 g
    GEE (2 1996 General Motors 4.3-LV6
    gasoline engines; conventional
    Chevron Phillips gasoline, U.S.
    average composition) (CO, NO, N02,
    S02, THC) (PM25 composition- EC,
    OC, S04, NH4, N03)
    
    Simulated downwind coal emission
    atmospheres (SDCAs) (fly ash, gas-
    phase pollutants, sulfate aerosols, NO,
    N02, S02)
    
    Paved Road Dust (RD)  (Los Angeles,
    CA; New York City, NY;  Atlanta, GA)
    
    Particle Size: GEE: 150 nm (MMAD),
    RD: 2.6+1.7 pm.SDCA: 0.1-1.Opm
    Route: Nose-only Inhalation
    
    Dose/Concentration: GEE: 60 pg/m3, SDCAs:
    317-1072 pg/m3, RD: 306-954 pg/m3; GEE: 00-
    104 ppm, NO-16.7 ppm, N02-1.1 ppm, S02-
    1.0 ppm, THC- 12ppm; SDCAs: CO- <1 ppm,
    NO- 0.19-0.62 ppm, N02- 0.10-0.37 ppm, S02-
    0.07-0.24 ppm, THC- <1  ppm
    
    Time to Analysis: 6 h exposure. Cannula
    ligated  into trachea and connected to rodent
    ventilator. Thorax and abdomen opened.
                                               GEE produced CL in the lungs, heart, and liver.
                                               RD produced a significant effect in the heart at
                                               the low dose. SDCAs had no effect on CL. RD
                                               significantly increased the heart's oxidative
                                               stress, as demonstrated by the TBARS levels..
    Reference:
    Simkhovich et al.
    (2007, 0965941
    
    Species: Rat
    
    Gender: Female
    
    Strain: Fischer 344 x
    Brown Norway hybrid
    
    Age: 4, 26 mo
    Ultra Fine Particles (UFPs) isolated
    from industrial diesel reference PM
    2975
    
    Particle Size: UFPs < 0.1 pm
    Route: Heart Perfusion (ex-vivo)
    
    Dose/Concentration: UFPs 12.5, 25, and 37.5
    mg.
    
    Time to Analysis: Hearts perfused w/ UFPs for
    30 min and analysis conducted every 10 min.
                                               Young adult and old hearts demonstrated equal
                                               functional deterioration in response to direct
                                               infusion of UFPs. Developed pressure in young
                                               adult UFPs-treated hearts fell from 101 ± 4 to 68
                                               + 8 mmHg.  In the old UFPs-treated hearts
                                               developed pressure fell by 35%. Positive dP/dt
                                               was equally affected in the young adult and old
                                               UFPs-treated hearts and was decreased by 28%
                                               in both groups.
    December 2009
                                                   D-22
    

    -------
           Study
                Pollutant
                   Exposure
                                                               Effects
    Reference: Smith et al.
    (2006,1108641
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 8 wk
    
    Weight:  260-270 g
    CFA: Coal Fly Ash (400 MW, Wasatch
    Plateau, Utah) (aerodynamic
    separation)
    
    Particle Size: 0.4-2.5pm
    Route: Nose-only Inhalation
    
    Dose/Concentration: 1400 pg/m3 PM25
    including 600 pg/m3 PM,
    
    Time to Analysis: 4 h/day for 3 consecutive
    days. Parameters measured 18 or 36 h post-
    exposure.
                                              Hematology: Plasma protein increased at 18h.
                                              Lymphocyte and hematocrit percentage
                                              decreased at 36 h.
    Reference: Stinn et al.
    (2005, 0883071
    
    
    Species: Rat
    
    Gender: Male and
    Female
    
    Strain: Crl: (WIU BR
    
    Age: 40  day
    DE (generated from 1.6 L VWdiesel
    under USFTP 72)
    
    CO: 10, 37 ppm
    C02: 2170, 6540 ppm
    NO: 7.0, 22.8 ppm
    NOX: 8.6, 28.3 ppm
    S02: 0.83, 3.09 ppm
    NH4: ND
    
    Measured Major Components: NO,
    S02,1-nitropyrene, Zi.  50% by DE
    weight is EC.
    
    Particle Size: 0.19-0.21 pm (MMAD)
    Route: Nose-only Inhalation
    
    Dose/Concentration: 3 and 10 mg/m3
    
    Time to Analysis: 6 h/day, 7 day/wk for 24 mo;
    6 mo post-exposure
                                              Hematology: Erythrocyteswere unaffected (12,
                                              24, 30) except in high dose females at 24 and 30
                                              mo. Hemoglobin and hematocrit increased dose-
                                              dependently with no gender differences.
                                              Leukocytes increased in a dose- and time-
                                              dependent manner.
    Reference: Sun et al.
    (2005, 0879521
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 16 wk
    CAPs: PM25 from Tuxedo, NY.
    
    HFCD: High Fat Chow Diet
    
    NCD: Normal Chow Diet
    
    Particle Size: PM25
                                  'm3; Daily
    Route: Whole-body Inhalation
    
    Dose/Concentration: PM25:
    concentration: 10.6 (SD3.4) pg/m1 (mean)
    
    Average exposure over 6 mo period: 15.2
    pg/m3.
    
    Time to Analysis: Study diets fed for at least
    10 wk prior to exposure to PM2 5 or FA. Exposed
    for 6 h/day, 5 days/wk for 6 mo. Sacrificed 15-
    47 days after exposure.
    Vasomotor Function: Mice fed HFCD and
    exposed to PM25 demonstrated an increase in
    the half-maximal dose for dilation to ACh with no
    changes in peak relaxation compared to the mice
    exposed to FA and fed HFCD and NCD.
    
    Atherosclerosis Burden with PM25: In vivo MRI
    imaging of atherosclerosis burden in the
    abdominal aorta revealed significantly increased
    plaque burden in the mice fed HFCD compared
    with the mice fed NCD. Mean (SD) plaque areas
    in the mice exposed to PM2 5 and fed HFCD vs.
    mice exposed to FA and fed HFCD were 33 (10)
    vs. 27 (13) units, respectively.
    
    Plfe and Vascular Inflammation: A 2.6-fold
    higher inducible NOS content was apparent in
    the mice exposed  to PM2 5 and fed HFCD com-
    pared with the mice exposed to FA and fed HFCD
    chow and a 4-fold  increase in the mice exposed
    to PM2 5 and fed NCD compared with the mice
    exposed to FA and fed NCD.
    Reference: Sun et al.
    (2008, 1570331
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 6 wk
    CAPs PM25
    
    Collected from Sterling Forest State
    Park, Tuxedo NY (40 miles NW of
    Manhattan)
    
    Particle Size: PM25
    Route: Whole-body Inhalation
    
    Dose/Concentration: Average Concentration
    of: 85 pg/m3 CAPs in chamber.
    
    Average exposure over 6 mo was 15.2 pg/m3.
    
    Time to Analysis: 6 h/day, 5 day/wk for 6 mo.
    
    Mice received two different diets, high-fat chow
    and normal-chow.
                                              Macrophage and Tissue Factor Expression in
                                              Aortic Segments: Tissue Factor (TF) expression
                                              was noted predominantly in the extracellular
                                              matrix surrounding macrophages, foam cell-rich
                                              areas and around smooth muscle cells.
    
                                              1. High-Fat Diet: Increased TF and increased
                                              macrophage infiltration was observed in the
                                              plaques of high-fat chow mice exposed to PM
                                              compared to mice exposed to air and high fat
                                              diet.
    
                                              2. Normal Diet: PM-exposed mice saw an
                                              increase in CD68 expression compared to air-
                                              exposed. However TF expression was not
                                              significantly different in PM exposed  normal diet
                                              mice compared to control normal diet mice.
    December  2009
                                                  D-23
    

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           Study
                Pollutant
                   Exposure
                      Effects
    Reference: Sun et al.
    (2008, 1570331
    
    Species: Human
    
    Cell Lines: BEAS-2B;
    Vascular Smooth
    Muscle Cells (hSMCs);
    and Monocytes (THP-
    1)
    Ambient Particles collected from
    Sterling Forest State Park, Tuxedo, NY
    (24h/dayfor4wk)
    
    Particle Size: Particle size ranges: 1.
    <0.18|jm
    2.1.8-2.5pm or
    3. 2.5-10pm
    Route: In vitro
    
    Dose/Concentration: 10-300 pg/ml
    
    Time to Analysis: Doses were tested for
    durations up to 24 h.
    Dose durations tested for up to 24-h did not
    indicate detectable effects on cell viability.
    
    Effect of PM on TF Expression and Activity in
    hSMCs: In the PM size range of 1-3 pm,
    significant increases in TF expression was
    observed at doses of 100 and 300 pm /ml. In the
    <0.18 pm size range, significant increase in TF
    expression was observed at all doses. The
    particles with sizes 0.18 -1.0 pm did not induce
    significant change in TF expression.
    
    Effect of PM on TF Expression and Activity in
    Monocyte  Cells: TF protein expression
    increased with O.18 pm and the 1-3 pm range
    particles. Expression was increased in the 0.18-
    1.0 pm  particle range but it was limited  compared
    to the other PM size ranges. In general TF
    expression was higher in monocytes than in
    hSMCs cells, but not significantly.
    
    Effect on TF Expression and Activity in
    Bronchial  Epithelial Cells: 100 pg/mLofthe 1-3
    pm and O.18 pm particles significantly increased
    TF expression.
    
    TF mRNA Expression: TF mRNA was increased
    rapidly within the first hour in response  to SRM-
    1694a PM. The lowest dose of SRM PM,0 pg/mL
    induced highest levels of mRNA in hSMCs, no
    further increase was observed at higher
    concentrations.
    Reference: Sun et al.
    (2008, 1570321
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 500-650 g
    PM25orUFP
    
    Particle Size: PM25; UFP: <0.1 pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: Mean PM25
    concentration: 79.1 ± 7.4 pg/m .  Normalized
    PM25 over 10wk period: 14.1 pg/m3.
    
    Time to Analysis: 6 h/day, 5 day/wk random
    exposure to PM2 5, UFP, or FA for a total of 10
    wk. At the end of wk 9 exposure,  rats were
    infused w/ 0.75 mg/kg/day of All for 7 days.
    PM25, UFP, or FA, continued during All infusion
    period.
    
    All = angiotensin II
    Mean Arterial Pressure (MAP): After All
    infusion, MAP was significantly higher in PM2 5 -
    All vs. FA-AII group. Aortic Vasoconstriction to
    PE was potentiated with exaggerated relaxation
    to the Rho-kinase (ROCK) inhibitor Y-27632 and
    increase in ROCK-1 mRNA levels in the PM25 -
    All group. Superoxide production in the aorta was
    increased in the PM25. All group compared to FA-
    AII group, inhabitable by apocynin and L-NAME
    with coordinate upregulation of NAD(P)H oxidase
    subunits p22phox and p47phox and depletion of
    tetrahydrobipterin.
    Reference: Sun et al.
    (2008, 1570321
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 500-650 g
    
    Cell Line: Primary Rat
    Aortic Smooth Muscle
    Cells (RASMCs)
    PM25orUFP
    
    Particle Size: PM25; UFP: <0.1 pm
    Route: Cell Culture
    
    Dose/Concentration: UFP, PM25:10 or 50
    pg/mL;AII: 100nmol/L
    
    Time to Analysis: Exposed to UFP or PM25
    and parameters measured at 0,1, 3, 6, and 15
                                       All = angiotensin I
    Exposure to UFPs and PM25 was associated with
    an increase in ROCK activity,  phosphorylation of
    myosin light chain, and MYPT1. Pretreatment
    with N-Acetylcysteine and the Rho kinase
    inhibitors (Fasudil and Y-27632) prevented MLC
    and MYPT-1 phosphorylation  by UFPs sug-
    gesting a superoxide-mediated mechanism for
    PM2 5 and UFPs effects.
    December 2009
                                                   D-24
    

    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Sun et al.
    (2009, 1904871
    
    Species: Mouse
    
    Gender: Male
    
    Strain: C57BL/6, c-
    fmsYFP (transgenic,
    yellow fluorescent
    protein under
    monocyte-specific
    promoter)
    
    Age: 8,10wk
    
    Weight: NR
    PM (concentrated- northeastern
    regional background; Tuxedo Park,
    NY)
    
    Particle Size: 2.5 pm (diameter)
    Route: Whole-body Inhalation. IT Instillation.
    
    Dose/Concentration: Exposure chamber
    (mean): 72.7 pg/m3, IT: 1.6mg/kg
    Metabolic Impairment: PM induced insulin,
    homeostasis model assessment indexes,
    elevated glucose, and abnormalities in lipid
    profile consistent with the IR phenotype.
                                       Time to Analysis: C57BL/6 mice, fed high-fat    Vascular Endothelium: PM decreased peak
                                       chow 10wk. Exposed in vivo 6 h/day, 5 day, 128  relaxation and ED50 to ACH and peak relaxation
                                       days. fmsYFP rendered diabetic or fed normal    to insulin  Lower levels of NO release were seen
                                       chow 10 wk. IT instilled with PM 2 times/wk for
                                       10 wk.                                      Insulin Signaling: PM reduced the
                                                                                  phosphorylation of Akt in intact aorta. PKC-|311
                                                                                  was the only PKC isoform to increase.
    
                                                                                  Adipose Inflammation, Visceral Adiposity: PM
                                                                                  significantly increased TNF-a, IL-6, E-selectin,
                                                                                  ICAM-1, plasminogen activator inhibitor-1, and
                                                                                  restin. PM increased visceral and mesenteric fat
                                                                                  mass. F4/80+ macrophages in fat tissue and
                                                                                  adipocyte size increased. PM downregulated IL-
                                                                                  10 and glactose-N-acetylgalactosamine-specific
                                                                                  lectin.
    
                                                                                  YFP Cell Adhesion and Infiltration: PM
                                                                                  increased YFP cells in the adipose tissue, YFP
                                                                                  cell infiltration in the mesenteric fat, and YFP cell
                                                                                  adhesion to endothelium.
    Reference: Tamagawa  PM10 (urban; Ottawa, Canada)
    et al. (2008, 1919881
                          Particle Size:: 0.8 + 0.4 pm (mean
    Species: Rabbit        diameter)
    
    Gender: Female
    
    Strain: New Zealand
    White
    
    Age: 12 wk
    
    Weight: Acute
    (average)-2.4 ±0.2 kg,
    Chronic (average)- 2.7
    ± 0.3 kg
                                       Route: Intrapharyngeal Instillation
    
                                       Dose/Concentration: Acute- 2.6mg/kg,
                                       Chronic- 2mg/kg
                                               Inflammation: PM10 induced more
                                               macrophages, AMs, positive and activated AMs,
                                               and fewer tissue macrophages.  NO, WBCand
                                               PMN were only significantly higher in the first two
                                               wk and IL-6 in the first wk.
                                       Time to Analysis: Acute animals exposed days
                                       1, 3, 5. Chronic animals exposed 2 times/wk for  Vascular endothelial function: PM10
                                       4wk.
                                                                                  significantly reduced Ach-stimulated relaxation
                                                                                  and did not alter SNP-stimulated relaxation. A
                                                                                  significant inverse relationship between IL-6 and
                                                                                  Ach-induced relaxation occurred at wk 1 in the
                                                                                  acute model and wks 1 and 2 in the chronic
                                                                                  model.
    
                                                                                  AMs: The chronic model had a significant
                                                                                  correlation between IL-6 and both positive and
                                                                                  activated AMs at wk 1. A significant inverse
                                                                                  relationship occurred between Ach and both the
                                                                                  volume fraction of positive and activated AMs.
    Reference: Tankersley  Carbon black (CB) (Wright dust feed
    et al. (2008,1570431    particle generator-BGI, Waltham, MA)
    Species: Mouse
    
    Gender: Male
    
    Strain: C57BL/6,
    C3H/HeJ, B6C3F1
    
    Age: 18, 28 mo
    
    Weight: NR
    Particle Size: 0.1-1. Opm
    Route: Whole-body Inhalation
    
    Dose/Concentration: Average PM25
    concentration- 401 ± 46 pg/m , Average PMi0
    concentration- 553 + 49 pg/m3
    
    Time to Analysis: 3 h/day, 4 days
    Hemodynamics: CB significantly elevated right
    atrial and ventricular pressures, pulmonary
    arterial pressure and vascular resistance, all of
    which were more pronounced in the 28 mo-old
    mice.  RV contractility (specifically, the ejection
    fraction and maximum change in pressure over
    time) reduced in CB-exposed 28 mo-old mice.
    
    Heart Tissue: CB significantly declined Ca2+-
    dependent NOS activity and was more
    pronounced in 28 mo-old mice,  who also had
    NOS2 upregulated. CB enhanced ROS
    generation and NOS-uncoupling and was
    greatest in 28 mo-old mice. CB also increased
    MMP-2, MMP-9, ANP,  BNP, which were greatest
    in 28 mo-old mice. CB also reduced PKG-1 in 28
    mo-old mice.
    December 2009
                                                   D-25
    

    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Tankersley  Carbon Black (CB)
    etal. (2007,091910)    partic|eSjze: c& 2 4pm (MMAD)
    
    Species: Mouse        (GSD 2.75 pm).
    
    Gender: Male
    
    Strain: C3H/HeJ and
    C57BL/6J
    
    Age: 10 wk
    
    Weight: 22-26 g
                                       Route: CB: Whole-body Inhalation;
                                       Sympathetic (S) & Parasympathetic (PS)
                                       blockade: IP Injection
    
                                       Dose/Concentration: CB: 159 + 12 pg/m3; PS
                                       (atropine): 0.5 mg/kg; S(propanolol): 1 mg/kg
    
                                       Time to Analysis: Successive 3 h CB and FA
                                       Exposures: conducted from 9 a.m. to 1 p.m., or
                                       at least 3 h after dark-to-light transition
                                       (exposure period selected based on the nadir in
                                       circadian pattern in HR responses).
    
                                       Subgroups of both strains exposed to PS S S
                                       blockade.
                                               FA Exposure with Saline: A significantly greater
                                               3 h average response occurred in C3 compared
                                               with B6 mice.
    
                                               PS Blockade: No evident strain difference
                                               between C3 and B6 was observed.
    
                                               S Blockade: 3 h average HR responses for C3
                                               mice were significantly reduced compared with
                                               saline.
    
                                               CB Exposure: HR responses were significantly
                                               elevated in C3 compared with B6 mice, but these
                                               HR responses were not different relative to  FA
                                               exposure.
    
                                               S Blockade: HR was significantly elevated  in B6
                                               mice during CB relative to FA, but was not
                                               changed in C3 mice.
    Reference: Tankersley  Carbon Black (CB) and Filtered Air
    et al. (2004, 0943781    (FA)
    Species: Mice
    
    Strain: AKR/J
    
    Age:-180 days
                          Particle Size: CB: 0.1 to 1 urn.
                                       Route: Whole-body Inhalation
    
                                       Dose/Concentration: CB average
                                       concentration: 160±22|jg/m3
    
                                       Time to Analysis: FA exposure on day 1, CB
                                       exposure 3 h/day for 3 consecutive days (days
                                       2-4)
                                               On day 1, HR was significantly depressed during
                                               FA in terminally senescent mice. By day 4, HR
                                               had significantly slowed due to the effects of 3
                                               days CB exposure. The combined effects of
                                               terminal senescence and CB exposure acted to
                                               depress HR to an average (+ SEM) 445 + 40
                                               bpm, ~ 80 bpm lower compared to healthy HR
                                               responses. The change in rMSSD was
                                               significantly greater on day 1 and day 4 in
                                               terminally senescent mice, compared to healthy
                                               mice. LF/HF ratio was significantly depressed in
                                               terminally senescent mice on day 1. By day 4,
                                               significant increases in LF/HF were evident in
                                               healthy mice during CB exposure. Terminally
                                               senescent mice modulated a lower HR without
                                               change in the LH/HF ratio during CB exposure.
    Reference: Thomson
    et al. (2005, 0875541
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344
    
    Weight: 200-250 g
    Urban Ambient Particles (EHC-93)
    from Ottawa, Canada; 03
    
    Particle Size: Respirable Modes
    (aerodynamic diameter): 1.3 and 3.6
    pm. Non-respirable Mode
    (aerodynamic diameter): 15 pm
    Route: Nose-only Inhalation
    
    Dose/Concentration: EHC-93: 0, 5, 50 mg/m3;
    
    03: 0, 0.4, 0.8 ppm
    
    Time to Analysis: 4 h to particles, 03, or
    combination of particles and 03.
    Both pollutants individually increased preproET-1,
    ET-1 and endothelial NOS mRNA levels in the
    lungs shortly after exposure, consistent w/ the
    concomitant increase in plasma of ET-1 [1-21].
    Prepro-ET1 mRNA remained elevated 24 h post-
    exposure to particles but no after 03.  Both
    pollutants transiently increased ET-B  receptor
    mRNA expression, while 03 decreased ET-A
    receptor mRNA levels. Coexposure to particles
    plus 03 increased lung preproET-1 mRNA but not
    plasma ET-1[1-21], suggesting alternative proc-
    essing or degradations of endothelins. This
    coincided w/ an increase of MMP-2 in the lungs
    (this enzyme cleaves bigET-1 to ET-1 [1-32]).
    Reference: Thomson
    et al. (2006, 0974831
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344
    
    Weight: 200-250 g
    Urban Ambient Particles (EHC-93)
    from Ottawa, Canada; 03
    
    Particle Size: NR
    Route: Nose-only Inhalation
    
    Dose/Concentration: EHC-93: 0, 50 mg/m3;
    
    03:0, 0.8 ppm
    
    Time to Analysis: 4 h to particles, 03, or
    combination of particles and 03. Sacrificed
    immediately following exposure or following
    24 h  recovery.
    Circulating levels of both ET-1[1-21] and ET-3[1-
    21] were increased immediately after exposure to
    PM and 03. While expression of preproET-1
    mRNA in the lungs increased, expression of
    preproET-3 mRNA decreased immediately after
    exposure. PreproET-2 mRNA was not detected in
    the lungs, and exposure to either pollutant did not
    affect plasma ET-2 levels. Coexposure to 03 and
    particles, while altering lung preproET-1 and
    preproET-3 mRNA levels in a fashion similar to
    03 alone, did not cause changes in the circulating
    levels of the two corresponding peptides.
    December 2009
                                                   D-26
    

    -------
           Study
                Pollutant
                   Exposure
                      Effects
    Reference: Totlandsdal
    et al. (2008, 1570561
    
    Species: Rat
    
    Gender: Male
    
    Strain: WKY/NCrl and
    Crl: Wl (Han)
    
    Age: Adult
    
    Weight: Crl/WI, 250-
    300 g
    
    Use: Isolation of Rat
    Ventricular
    Cardiomyocytes and
    Cardiofibroblasts
    (RVCMsandRVCFBs)
    Pigment Black Printex 90 (Frankfurt,
    Germany); PM:SRM 1648
    
    Particle Size: Printex 90:12-17 nm;
    PM:NR
    Route: Cell Culture
    
    Dose/Concentration: Printex 90: 0, 50,100,
    200 or 400 pg/mL; PM: 0, 200 pg/mL
    
    Time to Analysis: 20 h
    Cardiac Cell Cultures: IL-6 release was strongly
    enhanced upon exposure to conditioned media,
    and markedly exceeded the response to direct
    particle exposure. IL-1, but not TNF-a, seemed
    necessary, but not sufficient, for this enhanced
    IL-6 release. The role of IL-1 was demonstrated
    by use the use of an IL-1 receptor antagonist that
    partially reduced the effect of the conditioned
    media, and by a stimulating effect on the cardiac
    cell release of IL-6 by exogenous addition of IL-1
    a and IL-113.
    Reference: Tzeng et
    al. (2007, 0978831
    
    Species: Rat
    
    Strain: Wistar Kyoto
    
    Cell Type: Primary
    Vascular Smooth
    Muscle Cell Culture
    (VSMCs): isolated from
    thoracic aortas from
    200-250 g rats.
    Motorcycle Exhaust Particulate Extract  Route: In vitro
    (MEPE) collected from a Yamaha
    motorcycle with a 50 cm3 two-stroke
    engine using 95% octane unleaded
    gasoline.
    
    Particle Size: PM,, PM25, PM10
    Dose/Concentration: 10-100 pg/mL
    
    Time to Analysis: 3 days
    Exposure of VSMCs to MEPE (10-100 pg/mL),
    enhanced serum-induced VSMC proliferation.
    The expression of proliferating cell antinuclear
    antigen was also enhanced in the presence of
    MEPE. VSCMs treated with MEPE induced
    increase COX-2 mRNA, protein  expression, and
    PGE2 production, whereas the level of COX-1
    protein was unchanged. MEPE increased the
    production of ROS in VSMCs, in a dose-
    dependent manner. MEPE triggered time-
    dependent ERK1/2 phosphorylation in VSMCs
    which was attenuate by antioxidants (MAC,
    PDTC). The level of translocation of NF-KB-p65
    in the nuclei of VSMCs was also increased
    during MEPE exposure. The potentiating effect of
    MEPE in serum-induced VSMC  proliferation was
    abolished by COX-2 selective inhibitor NS-398,
    specific ERK inhibitor PD98059, and antioxidants
    (MAC, PTDC).
    Reference: Tzeng et
    al. (2003, 0972471
    
    Species: Rat
    
    Strain: Wistar Kyoto
    
    Cell Type: Primary
    Vascular Smooth
    Muscle Cell Culture
    (VSMCs)
    Motorcycle Exhaust Particulate Extract  Route: In vitro
    (MEPE) collected from a Yamaha
    motorcycle with a 50 cm3 two-stroke
    engine using 95% octane unleaded
    gasoline.
    Particle Size: NR
    Dose/Concentration: MEPE: 10 pg/mL;
    Nifedipine: lOpmol; Manganese Acetate: 100
    pmol; Staurosporine: 1-2 nM; Chelerythrine: 1
    pm
                                       Time to Analysis: 18 h
    MEPE induced a concentration-dependent
    enhancement of vasoconstriction elicited by
    phenylephrine in the organ cultures of intact and
    endothelium-denuded aortas for 18h. Nifedipine,
    manganese acetate, and Staurosporine, but not
    Chelerythrine, inhibited the enhancement of
    vasoconstriction by MEPE. ML-9 inhibited the
    enhancement of vasoconstriction by MEPE.
    MEPE enhanced the  phosphorylation of 20k-Da
    in rat vascular smooth muscle cells. N-
    acetylcysteine significantly inhibited the
    enhancement of vasoconstriction by MEPE. A
    time-dependent increase in ROS production by
    MEPE was also detected in primary cultures of
    VSMCs.
    Reference: Upadhay
    et al. (2008, 1593451
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 6 mo
    
    Weight: NR
    Ultrafine Carbon Particles (UFCP)
    
    Particle Size: Size- 31 + 0.3 nm,
    MMAD- 46 nm, Surface area
    concentration-0.139 m  particles/m ,
    Mass specific surface area- 807m2/g
    Route: Whole-body Inhalation
    
    Dose/Concentration: 172 pg/m3
    
    Time to Analysis: Acclimatized 2 day.  1 day
    baseline. 24 h exposure. 4 recovery. Sacrificed
    1st or 3rd day of recovery.
    Cardiophysiology: The mean arterial BP and
    HR increased but returned to baseline levels by
    the 4th recovery day. SDNN and HRV decreased.
    RMSSD and LF/HF decreased but were not
    significant.
    
    Pulmonary Inflammation: UFCP did not cause
    pulmonary inflammation.
    
    Pulmonary and Cardiac Tissue: HO-1, ET-1,
    ETA, ETB, TF, PAI-1 significantly increased in the
    lung on the 3rd recovery day. HO-1  was
    repressed in the heart, but the other markers had
    slight, nonsignificant increases.
    
    Systemic Responses: Neutrophil and
    lymphocyte cell differentials significantly
    increased on the 1st recovery day. Other blood
    parameters were unaffected. The plasma renin
    concentration increased on the first 2 recovery
    days. Ang I and II concentrations increased on
    the 1st recovery day but was not significant.
    December 2009
                                                   D-27
    

    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Wallenborn  Zinc Sulfate (ZnS04, aerosolized)
    et al. (2008,1911711
         v	Particle Size: NR
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    Age: 13 wk
    
    Weight: NR
                                       Route: Nose-only Inhalation
    
                                       Dose/Concentration: 9.0 + 2.1 pg/m3, 35 + 8.1
                                       pg/m3,123.2 + 29.6 pg/m3
    
                                       Time to Analysis: Exposed 5 h/day, 3 days/wk,
                                       16wk. Half of the rats used for plasma/serum
                                       analysis, other half for isolation of cardiac
                                       mitochondria.
                                               A trend toward increased BALF protein was
                                               seen. Cardiac mitochondrial ferritin had a small,
                                               significant increase. Mitochondrial succinate
                                               dehydrogenase and glutathione peroxidase had
                                               small, significant decreases. Subchronic
                                               exposure to 100 pg/m3 caused expression
                                               changes of cardiac genes involved with cell
                                               signaling events, ion channels regulation, and
                                               coagulation. No pulmonary-related effects were
    Reference: Wallenborn  PM: precipitator unit power plant
    et al. (2007,1561441    residual oil combustion
    Species: Rat
    
    Gender: Male
    
    Strain: WKY, SH, and
    stroke-prone SH
    (SHRSP)
    
    Age: 12-15 wk
    Particle Size: PM: 3.76pm (bulk) ±
    2.15
    Route: IT Instillation
    
    Dose/Concentration: WKY vs SHRSP: 1.11,
    3.33, 8.33 mg/kg
    
    SH vs SHRSP: 3.33, 8.33 mg/kg
    
    Time to Analysis: Single, 24 h
    
    Note: 4 h post-exposure study done on WKY vs
    SHRSP but not published.
    Oxidative Stress - Cardiac: SOD increased in
    the SHRSP vs WKY experiment only. Only
    SHRSP at 8.33 mg/kg showed a significant
    increase when compared to the control.
    
    GPx: No action but SHRSP levels were similar to
    SHR and, in the WKY vs SHRSP experiment,
    SHRSP exhibited higher activity level than WKY.
    
    Ferritin: Equivocal results were observed. Levels
    decreased at the high dose for WKY and SHRSP
    but increased at medium doses for SH and
    SHRSP.
    
    ICDH: Levels increased for WKY and decreased
    for SHRSP.
    Reference: Wellenius   CAPs
    et al. (2003, 055691
    Species: Dog
    
    Gender: Female
    
    Strain: Mixed mongrel
    
    Age: NR
    
    Weight: 14-17 kg
                          Particle Size: 0.26 + 0.04 pm
                                       Route: Permanent Tracheostomy
    
                                       Dose/Concentration: Median: 285.7 pg/m3,
                                       Range: 161.3-957.3 pg/m3
    
                                       Time to Analysis: Thoracotomy and
                                       tracheostomy performed. 5-13 wk recovery.
                                       Pairs of subjects: exposed 6 h/day either 2nd or
                                       3rd exposure time and filtered air other days. 5
                                       min preconditioning occlusion. 20 min rest
                                       interval. 5 min experimental occlusion. Some
                                       dogs exposed 6 h/d, 4 days (consecutive),
                                       filtered air on day 4.
                                               CAPs increased the ST-segment elevation and
                                               remained elevated 24 h after exposure. This
                                               increase was seen in precordial  leads V4 and V5.
                                               Multivariate regression analyses showed that the
                                               mass concentration of Si was significantly
                                               associated with the peak ST-segment elevation
                                               and integrated ST-segment change. Univariate
                                               regression analyses showed Pb to also be
                                               significantly associated with these  measures.
                                               CAPs had no effect on peak heart  rate during
                                               occlusion or the maximum occlusion-induced
                                               increase in heart rate.
    Reference: Wellenius   CAPs (Boston, MA); exposures during
    et al. (2004, 0878741    the period of 07/2000 and 01/2003.
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: Adult
    
    Weight: -250 g
    
    Use: Rat Model for
    Acute Myocardial
    Infarction (AMI):  Left-
    ventricular Ml induced.
    Animals allowed to
    recover for at least 12 h
    after surgery.
    CO
    
    Particle Size: PM25
    Route: Whole-body Inhalation
    
    Dose/Concentration: CO: 35ppm; CAPs
    (median concentration): 350.5 pg.m3;
    CAPs+CO: (CAPs median concentration):
    318.2 pg/m3
    
    Time to Analysis: 1 h exposure to CAPs or
    CAPs+CO for 1 h. Exposure to pollutants was
    preceded and followed by 1 h exposure to FA.
    CO exposure reduced the ventricular premature
    beat (VPB) frequency by 60.4% during the
    exposure time compared to controls. This effect
    was modified by both infarct type and the number
    of pre-exposure VPBs, and was mediated
    through changes in HR. Overall, CAPs exposure
    increased VPB frequency during the exposure
    period, but this did not reach statistical
    significance. This effect was modified by the
    number of pre-exposure VPBs. In rats with a high
    number of pre-exposure VPB, CAPS exposure
    significantly decreased VPB frequency (67.1%).
    Overall, neither CAPs nor CO had any effect on
    HR, but CAPs increased HR in specific
    subgroups. No significant interactions were
    observed between the effects of CO and CAPs.
    December 2009
                                                   D-28
    

    -------
           Study
                Pollutant
                    Exposure
                      Effects
    Reference: Wellenius
    et al. (2006, 1561521
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: Adult
    
    Weight: -250 g
    
    Use: Rat Model for
    Acute Myocardial
    Infarction (AMI):  Left-
    ventricular Ml induced.
    Animals allowed to
    recover for at least 12 h
    after surgery.
    CAPs: (Boston, MA)
    
    Particle Size: PM25
    Route: Whole-body Inhalation
    
    Dose/Concentration: CO: 35 ppm; CAPs
    (median concentration): 645.7 pg.m3;
    CAPs+CO: 37.9 ppm
    
    Time to Analysis: CAPs or CAPs+CO
    exposure for 1 h. Exposure to pollutants was
    preceded and followed by 1 h exposure to FA.
    Among rats in the CAPs group, the probability of
    observing supraventricular arrhythmias (SVA) de-
    creased from the baseline to exposure and post-
    exposure periods. The pattern was significantly
    different than that observed for the FA group
    during the exposure period. In the subset with
    one or more SVA during the baseline  period, the
    change in SVA rate from baseline to exposure
    period was significantly lower in the CAPs and
    CO groups only, when compared to the FA group.
    No significant effects were observed in the group
    simultaneously exposed to CAPs and CO.
    Reference: Wichers et
    al. (2004, 0556361
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 75 day
    HP-12 (oil-combustion derived PM
    obtained from inside wall of a Boston
    power plant stack burning residual oil
    number 6).
    
    Water-leachable constituents (pg/mg):
    S04 (217.3); Zn (11.4); Ni (6.9); Fe
    (0.0);V(1.3);Cu(0.2);Pb(0.0)
    
    1M HCI-leachable constituents
    (fjg/mg): S04 (220.6); Zn (15.5); Ni
     14.8); Fe (15.6); V (32.9); Cu(1.1);Pb
     1.7)
    
    Particle Size: 3.76 pm (MMAD) (GSD
    2.16)
    Route: IT Instillation
    
    Dose/Concentration: HP-12 (mg/kg): 0.00
     saline control), 0.83 (low), 3.33 (mid), 8.33
     high)
    
    Time to Analysis: 96 h or 192 h post-
    instillation.
    Exposures to mid and high-dose HP-12 induced
    large decreases in HR, BP, and body
    temperature. The decreases in HR and BP were
    most pronounced at night and did not return to
    pre-instillation values until 72 h (HR) and 48 h
    (BP) after dosing. ECG abnormalities (rhythm
    disturbances, bundle branch block) were
    observed primarily in the high dose group.
    Reference: Wold et al.
    (2006, 0970281
    
    Species: Rat
    
    Gender: Female
    
    Strain: SD
    
    Use: Left jugular vein
    and right carotid artery
    were cannulated.
    UFPs from either ambient air (UFAAs)
    or diesel engine exhaust (UFDGs);
    UFIDs from industrial forklift exhaust
    and soluble fraction UFID suspension,
    particle free (SF-UFID)
    
    Particle Size: UFAAs diameter < 150
    nm; UFDGs diameters 100 nm
    Route: IV Infusion
    
    Dose/Concentration: UFDG (50 pg/m)
    
    Time to Analysis: Infused w/UFAA or UFDG
    Monitored continuously for 1 h then sacrificed.
    Infusion of UFDGs caused ventricular premature
    beats (VPBs) in 2 out of 3 rats. Ejection fraction
    increased slightly in rats receiving UFAA and was
    unchanged in the UFDG and saline groups.
    Reference: Wold et al.
    (2006, 0970281
    
    Species: Rat
    
    Gender: Female
    
    Strain: SD
    UFPs from either ambient air (UFAAs)
    or diesel engine exhaust (UFDGs);
    UFIDs from industrial forklift exhaust
    and soluble fraction UFID suspension,
    particle free (SF-UFID)
    
    Particle Size: UFAAs diameter <150
    nm; UFDGs diameters 100 nm
    Route: Lagendorff Heart Perfusion
    
    Dose/Concentration: UFDG (100 pg/2ml);
    UFID (12.5 pg/l in perfusate); SF-UFID (12.5
    Time to Analysis: Lagendorff 1: Treated
    w/UFDG  Lagendorff 2: Treated with UFID &
    SFUFID.  Both experiments were monitored
    continuously for 1 h after injection.
    UFDGs caused a marked increase in left-
    ventricular and end-diastolic pressure (LVEDP)
    after 30 min of exposure. UFIDs caused a
    significant decrease in left-ventricular systolic
    pressure (LVSP) at SOmin after the start of
    infusion. This effect was absent when SF-UFID
    was studied.
    Reference: Yatera et
    al. (2008, 1571621
    
    Species: Rabbit
    
    Gender: Female
    
    Strain: WHHL
    
    Age: 42 wk
    
    Weight: 3.2 ±0.1 kg
    (avg)
    EHC-93 from Ottawa, Canada
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: PM10 suspension: 5 mg
    EHC-93 in 1 ml saline
    
    Time to Analysis: Exposed 2 times/wk for 4
    wk. Acute effects observed at 0.5,1, 2, 4, 8,12,
    and 24 h after initial instillation. Subchronic
    effects observed once/wk for 4 wk.
    Exposure to PM10 caused progression of
    atherosclerotic lesions in thoracic and abdominal
    aorta. It also decreased circulating monocytes
    expressing high levels of CD31 and CD49day,
    and increased expression of CD54 (ICAM-1) and
    CD106 (VCAM-1) in plaques. Exposure to PM,0
    increased the number of BrdU-labeled (*) mono-
    cytes into plaques and into smooth muscle
    underneath plaques.
    December 2009
                                                   D-29
    

    -------
           Study
                Pollutant
                                                                             Exposure
                      Effects
    Reference: Ying et al.
    (2009,1901111
    
    Species: Mice
    
    Gender: Male
    
    Strain: ApoE"'"
    
    Age: 16 wk
                          CAPs:,New York City (Manhattan), NY;   Route: Whole-body Inhalation
                          May-Sept 2007
                                                              Dose/Concentration: 138.4 + 83.7 pg/m
                          Particle Size: PM25
                                                              Time to Analysis: 6 h/day, 5 day wk, 4 mo
                                                                                   Vascular Tone: Significant decrease in PE-
                                                                                   induced maximum contraction of aortic rings in
                                                                                   CAPs-exposed mice. No difference in sensitivity
                                                                                   to PE between groups. Treatment with the
                                                                                   soluble guanylate cyclase inhibitor ODQ restored
                                                                                   the response to PE in CAPs aortic rings. No
                                                                                   significant differences in relaxation induced by
                                                                                   ACh. CAPs abolished the relaxation induced by
                                                                                   Ca ionophore A23187. CAPs exposure slightly
                                                                                   (but significantly) decreased maximum relaxation
                                                                                   induced by SNP
    
                                                                                   Protein Expression: iNOS mRNA expression
                                                                                   was increased in the aortas of CAPs-exposed
                                                                                   mice. eNOS and GTPCH levels were unchanged.
                                                                                   Distribution of inOS protein expression was
                                                                                   limited to plaque in air-exposed mice and was
                                                                                   found in the  plaque and media for CAPs-exposed
                                                                                                         Superoxide Production: Superoxide levels in
                                                                                                         CAPs-exposed mice were increased in the aorta
                                                                                                         compared to air-exposed mice. The addition of L-
                                                                                                         NAME significantly increased superoxide
                                                                                                         production. Extensive protein nitration in aortas of
                                                                                                         CAPs mice. NADPH subunits Pad and p47 phox
                                                                                                         mRNA expression was increased in aortas of
                                                                                                         mice exposed to CAPs.
    
                                                                                                         Atherosclerosis: Significant increase in plaque
                                                                                                         area of CAPs-exposed mice. Higher levels of
                                                                                                         macrophage infiltration, collagen deposition, and
                                                                                                         lipid composition of plaques from CAPs-exposed
                                                                                                         mice.
    Reference: Yokota et
    al. (2004, 0965161
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Weight: 345-498.2 g
    DEP (obtained from the Japan
    Automobile Research Institute)
    
    Particle Size: NR
                                                              Route: IT Instillation
    
                                                              Dose/Concentration: Group 1: DEP: 1 mg/0.1
                                                              ml; Group 2: DEP: 0.2 ml (10,12.5 or 25
                                                              mg/ml); Group 3: DEP 2.5 or 5 mg/0.2 ml
    
                                                              Time to Analysis: DEP pre-treatment 24-72 h
                                                              before ischemia/reperfusion.
    DEP Effects on Mmyocardial
    Ischemia/Reperfusion-induced Arrhythmia:
    An increased mortality was observed in the DEP
    group compared to the vehicle-treated group.
    46% of the animals in DEP died during the first 3
    min reperfusion period.  The animals of other
    groups were intratracheally instilled with DEP at
    the beginning of ischemia/reperfusion experi-
    ment, or were pretreated with polyethylene
    glycol-conjugated SOD (1000 lU/kg, iv). In these
    animals, incidences of both arrhythmia and
    mortality were similar to those in the animals
    treated with the vehicle.
    
    DEP Rffects on the  Biochemical and
    Hematological Parameters: Neutrophil count
    was elevated by a higher dose (5  mg) of DEP at
    24 h after the IT instillation, and oxygen radical
    production, which was induced by 12-0-
    tetradecanoylphorbol 13-acetate,  was enhanced
    at 72 h.
    Reference: Yokota et
    al. (2005, 0960031
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Weight: 303-472.2 g
    DEP from Japan
    
    Particle Size: NR
                                                              Route: IT Instillation
    
                                                              Dose/Concentration: DEP: 5 mg/animal
    
                                                              Time to Analysis: Single exposure 0.5,1, 2, 3,
                                                              6, 12, 24, 48 h.
    At 12 and 24 h post-instillation, circulatory
    neutrophil counts in the 5 mg DEP group were
    significantly elevated, and were 2.1-fold (12 h)
    and 2.3 fold (24 h) in vehicle treated animals. 1
    mg DEP caused an increase of approximately
    0.4-fold in CNC at 6 h. 12-0-
    tetradecanoylphorbol 13-acetate induced
    oxyradical production (ORP) in the isolated
    neutrophil was enhanced at 12 and 24 h after
    instillation with 5 mg DEP. In Serum, a marked
    elevation of CINC-1 and a slight elevation of MIP-
    2 were also observed, while TNF-a was not
    detected. GM-CSFwas not detected in serum 24
    h post-instillation.
    December 2009
                                                    D-30
    

    -------
           Study
                Pollutant
                   Exposure
                                                              Effects
    Reference: Yokota et
    al. (2008, 1901091
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ddy
    
    Age: NR
    
    Weight: 39.6-46.0 g
    DEP (DMSC (dichloromethane
    soluble-component), RPC (residual
    particle-component))
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 5 mg/kg, 10 mg/kg
    
    Time to Analysis: DMSC and RPC extracted
    from DEP. Mice acclimatized 7 day
    
    . DEP, DMSC, or RPC instilled. BALFand blood
    obtained and G-CSF, GM-CSF, IL-6 measured
    2,4,12, 24 h post-instillation.
                                             Inflammation: At 5 mg/kg DEP increased the
                                             total cell and macrophage count. DEP or RPC
                                             increased neutrophils at 5 and 10 mg/kg. 10
                                             mg/kg DEP or RPC increased macrophages at
                                             4h and decreased at 12 h.
                                                                               RPC or DEP caused sustained increases in RBC,
                                                                               WBC, and neutrophils.
    
                                                                               Cytokines: 5 mg/kg RPC markedly increased G-
                                                                               CSF and IL-6. Other cytokine increases at this
                                                                               dose were transient. 10 mg/kg DEP increased IL-
                                                                               6 at 4 h, and DEP or RPC increased G-CSF and
                                                                               IL-6 at 12 h. DEP or RPC also increased IL-1p.
    
                                                                               Myocardium: Myocardial MPO activity
                                                                               significantly increased in 5 mg/kg RPC at 12 and
                                                                               24 h. Myocardial MIP-2 increased the most in 5
                                                                               mg/kg RPC, while LIX tended to be lowered by
                                                                               RPC.
    Table D-2.      Respiratory effects:  in vitro studies.
           Study
                Pollutant
                  Exposure
                                                             Effects
    Reference: Aam and
    Fonnum (2007,
    1551231
    
    Species: Human, Rat
    
    Tissues/Cell Types:
    Human-Neutrophil
    Granulocytes (NG);
    
    Rat-AM
    DEP: SRM 1975
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: NG: 8.8 - 280 pg/mL
    
    AM: 140, 280|jg/mL
    
    Vitamin E = 5 pM
    
    Time to Analysis: 1 h
                                          ROS of NG: Formation of ROS in NG decreased
                                          with increased doses of DEP. Lucigenin
                                          chemiluminescence of ROS formation diminished
                                          25% at 8.8 pg/mL DEP and luminol
                                          chemiluminescence 32% with 17.5 pg/mL DEP. DCF
                                          fluorescence required much higher doses of DEP.
                                          Controls without PMA stimulation had highly reduced
                                          lucigenin and luminol with DEP dose of 140 pg/mL
                                          while DCF increased 116%.
    
                                          ROS of AM: 280 pg/mL of DEP decreased ROS
                                          level by 19% with  DCF. DEP with PMA-unstimulated
                                          cells increased 24% with  DCF.
    
                                          Necrosis: NG cell death was DEP dose-dependent.
                                          At 280 fjg/mL,  cell death increased 5.4% as
                                          compared to control. LDH concentration increased
                                          1.6% with 70 pg/mL DEP and 3.9% with 280 pg/mL
                                          after 1 h.
    Reference: Agopyan
    et al. (2003, 0560651
    
    Species: Human
    
    Tissues/Cell Types:
    BEAS-2B, NHBE,
    SAEC
    PC: synthetic carboxylate-modified
    particles
    
    Particle Size: 2,10pm
    Route: Cell Culture
    
    Dose/Concentration:
    
    PC2 = 0.83 g/mL or 3.4x109 particles/mL
    
    PC10 = 0.8 g/mL or 3x106 particles/mL
    
    Time to Analysis:
    
    PC2 = 12, 24, 8 h
    
    PC10 = 2, 6, 12, 24 h
                                          Calcium Imaging: PC10 induced increase of Ca2*
                                          concentration in all capsaicin-sensitive cells 100%.
                                          Similar reaction observed in cells exposed to PC2.
                                          However, more than 3-PC2s were required to induce
                                          a Ca increase unlike PC10. CPZ (10um) and
                                          amiloride could fully block PC-induced response.
    
                                          cAMP: Post 6 h, a dose-dependent increase in
                                          cAMP was observed. Again, CPZ blocked  increase
                                          by 70-90% depending on cell type: SAEC >NHBE ~
                                          BEAS-2B.
    
                                          Apoptosis: PC10 and PC2 induced apoptosis time-
                                          dependently. PC2 was slower in induction than
                                          PC10. Post 48 h, 80-95% cells were apoptotic in all
                                          cell types. Noncapaisin-sensitive cells (which did not
                                          bind to particles) did not exhibit apoptosis.  CPZ
                                          reduced apoptosis by 97% BEAS-2B, 96% NHBE
                                          and 98% SAEC. Amiloride did not block apoptosis.
    
                                          Necrosis: Induction of necrosis by PC2 and PC 10
                                          was negligible. A slight increase from 1 % to 2% was
                                          observed at 24-48 h in NHBE and SAEC. BEAS-2B
                                          showed slight decrease  from 3% to 4% in same time
                                          period.
    December  2009
                                                 D-31
    

    -------
           Study
                Pollutant
                                                     Exposure
                       Effects
    Reference: Agopyan
    et al. (2004, 1561981
    
    Species: Human,
    Mouse
    
    Tissues/Cell Types:
    Human-NHBE, SAEC;
    
    Mouse-Wildtype and
    TRPV1(-/-) Terminal
    Ganglion Neurons
    (TG)
    ROFA
    
    MSHA:MtSt Helen Ash
    
    Particle Size: NR
                                       Route: Cell Culture
    
                                       Dose/Concentration: 100 pg/mL ROFA or
                                       MSHA
    
                                       Time to Analysis: ROFA/MSHA in NHBE
                                       and SAEC = 2, 6, 24, 48 h
    
                                       ROFA/ MSHA in TG = 24 h
    Calcium Imaging in NHBE and SAEC: In 100% of
    reactive cells, ROFA/MSHA induced an increase in
    Ca2*. Levels remained elevated as long as PM
    bound to plasma membrane. Washing and disjoining
    PM from membrane caused Ca2* to slowly decline to
    baseline. CPZ (orCPZand amiloride) reversibly
    inhibited PM-induced  rises in Ca *.
                                                                              Calcium Imaging in TRPV1(+/+) and (-/-) mice
                                       cAMP measurements with NHBE and SAEC  sensory neurons: All sensitive neurons in
                                       exposed to ROFA/MSHA = 6 h              TRPV1(+/+) increased Ca  in response to ROFA.
                                         K                                    No effect of ROFA in TRPV1 (-/-).
    
                                                                              cAMP: ROFA and MSHA induced increases in Ca2*
                                                                              in NHBE and SAEC cells, which was completely
                                                                              blocked by cAM P.
    
                                                                              Apoptosis: ROFA or MSHA induced time-
                                                                              dependent apoptosis, peaking at 24 h. CPZ again
                                                                              inhibited this response. Neurons bound to PM
                                                                              (<25um) induced apoptosis in TRPV1 (+/+). Cells
                                                                              without bound PM or bound with PM (>25 pm)
                                                                              showed no effect. No apoptosis occurred in the
                                                                              absence of Ca *.
    
                                                                              Necrosis:  Necrosis for any of the cell types was
                                                                              negligible.
    
                                                                              PKA: Inhibition of PKA resulted in 90+% apoptosis
                                                                              in NHBE and SAEC. Again, no apoptosis was
                                                                              observed in a Ca2* free environment.
    Reference: Ahn et al.
    (2008, 1561991
    
    Species: Human
    
    Tissues/Cell Types:
    A549
    DEP: (6 cyl, 11L, turbo-charged, heavy-  Route: Cell Culture
    duty diesel engine, South Korea)
                                       Dose/Concentrations: 0,  1, 5,10, 50 and
                                       100|jg/mLofDEP
    Dex: anti-inflammatory (Sigma, St.
    Louis,  MO)
    
    Particle Size: NR
                                       Some cells pre-treated with 10, 20, 40, 50
                                       pg/mL of Dex.
    
                                       Time to Analysis: 24 h
    COX-2 Expression: Cells expressed dose-
    dependent increases in COX-2 expression after
    treatment with 10-100 pg/mL of DEP. Treatment of
    50 |jg/mL for 24 h induced statistically significant
    COX-2 expression in both mRNA and protein levels.
    Pre-treatment with Dex significantly reduced
    expression of COX-2 mRNA and protein. Dex
    treatment induced dose-dependent suppression of
    DEP-induced protein levels.
    
    PGE2 Levels: Levels of the inflammatory mediator,
    PGE2, increased when were cells exposed to 50
    |jg/mL of DEP. Pre-treatment with 50 pg /mL Dex
    completely inhibited  DEP-induced release of PGE2.
    Reference: Ahsan
    (2005, 1562001
    
    Species: Human
    
    Tissues/Cell Types:
    Trx-1-transfected
    Clone of Murine L-929
    cells; Control Clone (L-
    929-Neo1);A549
    DEP: provided by Dr.  Masaru Sagai,
    University of Health and Wfelfare,
    Aomori, Japan
    
    Particle Size: NR
                                       Route: Cell Culture
    
                                       Dose/Concentration:
    
                                       DEP: 50 pg/mL
    
                                       hTrx-1- or L-929-Neo1: 40 pg/mL
    
                                       Pretreatment: rhTrx-1 (10 pg/mL) or DM-
                                       rhTrx-1 (NR)
    
                                       Time to Analysis: Pretreatment for 1 h.
                                       Parameters measured 3 h post exposure.
    ROS: DEP induced significant increases of ROS in
    L929-Neo1 cells. hTRx-1 cells showed no affect. RT-
    PCR revealed hTrx-1 mRNA expression in
    transfected cells but not control L929-Neo1 cells.
    Endogenous murine Trx-1 mRNA expression
    increased in control cells, but not in hTrx-1 cells.
    A549 cells had increased ROS levels but these
    levels were suppressed with rhTrx-1 pretreatment.
    Pre-treatment with DM-rhTrx-1 increased ROS
    levels more.
    
    Akt (antiapoptotic molecule): Phosphorylated Akt
    prevents apoptosis. DEP induced phosphorylation of
    Akt in control cells after 3 h and dephosphorylation
    after 5 h. In hTrx-1 cells, Akt remained
    phosphorylated after 5 h. In A549 cells, Akt
    phosphorylated at 3 h and slowly turned off at 12-
    24 h. Pre-treatment with rhTrx-1  blocked
    dephosphorylation. This suggests that Trx-1
    preserves active form of Akt and thereby protects
    against cytotoxicity from DEP.
    December  2009
                                                   D-32
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Alfaro-
    Moreno et al. (2002,
    1562041
    
    Species: Human,
    Mouse, Rat
    
    Strain: Human-A549;
    Mouse-J774A.1,
    BALB-c
    
    Tissues/Cell Types:
    HUVEC, Mouse
    Fibroblasts, Rat Lung
    Fibroblasts (RLF)
    PMi0: Collected from 3 zones in Mexico  Route: Cell Culture
    City: North (industrial), Center
    (business) and South (residential)
    15000 cells/cm2 except:
    Particle Size: PM1(
    Cytotoxicity: Confluent Cultures 180,000
    cells/cm .
    
    DMA Breakage: 20,000 cells/well.
    
    Cytokine Assays: 180,000 cells/cm2
    
    Dose/Concentration: Cytotoxicity: 10, 20,
    40, 80, 160 pg/cm2
    
    Apoptosis: 160|jg/cm2
    
    DMA Breakage: 2.5, 5,10, 20, 40 pg/cm2
    
    Cytokine Assays: 10, 20, 40, 80 pg/cm2
    
    E-Selectin Expression: 40 pg/cm2
    
    Time to Analysis: Cytotoxicity: 24, 48, 72 h;
    Apoptosis: 24 h; DMA Breakage: 72 h;
    Cytokine Assays: 24 h
    Cytotoxicity: Cytotoxic effect exhibited dose-
    dependency after 72 h in proliferating cells of
    J774A.1, BALB-c and RLF cell lines.
    
    Proliferating Cells: Northern particles induced a
    statistically larger effect than central or southern
    particles. J774A.1 was more susceptible while
    BALB-c was less susceptible. A549 was most
    resistant to decreased viability during exposure. No
    significant variation in viability was observed when
    compared to the control. Particles were not cytotoxic
    among confluent cell growth for any cell lines when
    exposed to 20-160 pg/cm  .
    
    Apoptosis: Overall, particles induced low rates of
    cell death via apoptosis. J774A.1 depicted similar
    levels of apoptosis when exposed to three PM
    zones, -15% apoptotic cells measured. BALB-c was
    not reported. Results for the A549 measured
    apoptotic cells were: South- 4%, Central-11% and
    North-15%. HUVEC cells indicated an increase in
    apoptosis with northern particles.
    
    DMA Breakage: PMi0 from all zones induced DNA
    breakage. A dose-dependent relationship was
    established with PM2s particles at concentrations of
    10 pg/cm2. The Southern zone required a higher
    dose of PM  (10 pg/cm2) to produce the same effect
    as other zones (2.5  pg/cm2).
    
    Cytokines:  Particles induced TNF-a and IL-6
    secretion in  J774A.1 cells dose-dependently IL-6
    increased significantly with central particles. PGE2
    secretion in  RLF cells induced by exposure to PM
    showed dose-dependent responses. PM from the
    central zone induced the most PGE2 secretion. Max
    secretion was observed at doses of 40 pg/cm2 from
    all three PM zones.
    
    E-Selectin Expression: HUVEC cells showed a
    25% increase in E-selectin expression after
    exposure to 40 pg/cm2 of PM.
    Reference: Amakawa  DEP (obtained from a 4JB1, Isuzu,      Route: Cell Culture
    Species: Mouse,
    Human
    
    Strain: Mouse-ICR
    
    Tissues/Cell Types:
    AMs
    
    Gender: Male
    
    Age: Mouse 6-7 wk;
    Human 20-24 yr
    1500rpm, 4cyl diesel engine)
    
    DEPE = DEP Extract (methanol)
    
    CB = Charcoal (Sigma)
    
    Particle Size: DEP- 0.4 pm, CB- 0.7
    pm
    cells/ml
    
    Dose/Concentration: DEP = 1 or 10 pg/mL;
    DEPE=1or10pg/mL;CB=1,10,100
    pg/mL
    
    Time to Analysis: Human cells pre-treated
    with LPS 1 pg/mL. Murine cells pre-treated
    with SOD 300 lU/mL. Parameters measured
    24 h post exposure.
    Cells: For mice, more than 90% of the cells were
    macrophages and over 90% were viable. For
    humans, 96% of the cells were macrophages, 3%
    lymphocytes and 1% neutrophils; over 95% of the
    human cells were viable.
    
    DEP Cytotoxicity: None observed
    
    Cytokines: DEP (10 pg/mL) suppressed release of
    TNF-a and IL-6 for both mice and  humans in a dose-
    dependent manner.  Murine cells pre-treated with
    LPS or IFN-y released even less TNF-a and  IL-6. IL-
    10 was unaffected. Human macrophages pre-
    treated with LPS also released lower levels of TNF-
    a,  IL-6 and IL-8.
    
    ROS: Pre-treatment of SOD on murine cells  partially
    attenuated the suppressive effect of DEP as  well as
    decreased the production of ROS  generated by  DEP
    (10pg/mL).
    
    Carbon: Carbon particles did not suppress TNF-a or
    IL-6 release from murine AMs; however,100 pg/mL
    of CB stimulated TNF-a production.
    
    Methanol: No Cytotoxicity nor cytokine release
    effects were observed.
    
    DEPE: DEPE suppressed TNF-a and IL-6 release in
    a similar way as DEP.
    December 2009
                                                   D-33
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Amara et   DEP = SRM 2975
    al. (2007, 156212)      ^   .    u      ,     _,     t
                         CSC = cigarette smoke condensates
    Species: Human       (collected from Kentucky standard
    ~....    ,^n  „,„,  cigarettes, 2R4F; University of
    Cell Lines: A549, NCI- Klntucky)
    H292
                         DC = DEP + CSC
    
                         CB (Degussa, Frankfurt, Germany)
    
                         Particle Size: CB: 95 nm; DEP: NR
                                       Route: Cell Culture
    
                                       Dose/Concentration: DEP = 5-10 pg/cm2
    
                                       CB=10|jg/cm2
    
                                       CSC=10|jg/cm2
    
                                       Time to Analysis: 6 or 24 h
                                            Inflammatory Markers: LDH of A549 was
                                            unaffected at either time point with DEP or CB. LDH
                                            increased with CSC at concentrations high than 10
                                            pg/mL at both time points. DC had no effect.
    
                                            Proteases: MMP-1 mRNA expression showed a
                                            dose dependent increase with DEP in A549 cells.
                                            DEP also increased MMP-1 in NCI-H292 cells. CB
                                            and CSC had no effect. MMP-1  mRNA expressions
                                            were inhibited by N-acetylcysteine antioxidant.
                                            Similar inhibition was observed with NOX4 oxidase.
                                            DC induced a similar effect to DEP. MMP-1  protein
                                            expression increased post 24 h  with DEP. MMP-2,
                                            TIMP-1, TIMP-2 mRNA expression was  unaffected.
    
                                            TGF: TGF-|3 mRNA expression was unaffected.
    
                                            ROS: DEP and DC increased ROS formation after 1
                                            h. DEP effect was inhibited by N-acetylcysteine
                                            antioxidant pre-treatment.
    
                                            MAP-Kinase: DEP induced MMP-1 expression
                                            increased ERK1/2  phosphorylation after 10 min,
                                            peaking at 30 min,  and  returning to normal levels at
                                            60 min. Treatment  with  CBPs did not increase
                                            ERK1/2 phosphorylation whereas treatment with
                                            CSC resulted in phosphorylation. Only inhibitors of
                                            ERK1/2 reduced DEP induced MMP-1 activity. P38
                                            and JNK inhibitors  had  no effect.
    Reference: Anseth et
    al. (2005, 0886461
    
    Species: Human
    
    Cell Lines: A549;
    A549-pO (lacking
    mitochondria)
    s-ROFA: soluble portion
    
    Particle Size: 1.95 +018 fjm
    Route: Cell Culture (3X105 cells/ml)
    
    Dose/Concentration: 100 |jg/mL
    
    Time to Analysis: Experiments conducted
    by spreading monolayer of Infasurf (calf lung
    surfactant extract on PBS, PBS+ROFA or
    conditioned media from A549 AEC.
    Parameters measured after one 6-h
    incubation  period.
    Lung Surfactant Gelation: ROFA alone and A549
    conditioned media alone did not significantly alter
    Infasurf rheology However, conditioned media from
    A549 AEC at 16  h induced a significant increase in
    elastic storage and viscous loss moduli. Inhibiting
    ROS production  lowered effect, indicating s-ROFA
    gelation mediated through ROS.
    
    ROS: ROS mediated through mitochondria as
    evidenced by the effect of ROFA-AEC on surfactant
    gelation in the presence of mitochondria ROS
    inhibitors as well as A549-pO cells.
    Reference: Auger et
    al. (2006, 1562351
    
    Species: Human
    
    Tissue/Cell Type:
    Nasal Epithelial Cells
    DEP:SRM1650
    
    PM25: obtained from a highway in
    Paris, France
    
    Particle Size: DEP: 400 nm (mean
    diameter); PM25
    Route: Cell Culture (2-3.5x104 cells/cm2)
    
    Dose/Concentration: 10-80 pg/cm2
    
    Time to Analysis: Cells treated on apical
    side. Parameters measured 24 h following
    treatment.
    Cytotoxicity (LDH): No cytotoxicity for DEP or
    PM25 (80 pg/cm2).
    
    Cytokines: In non-stimulated All cultures, IL-8 was
    the most abundantly secreted cytokine, followed by
    GM-CSF, TNF-a, and IL-6 in decreasing levels of
    production. Amphiregulin was moderately, but
    consistently, secreted. After treatment, both DEP
    and PM25 induced IL-8 and amphiregulin release in
    a dose-dependent manner through the basolateral
    surface. PM25 stimulated IL-6 and GM-CSF release
    through the apical surface.
    
    ICAM-1 expression: No effect from DEP or PM25.
    
    ROS: DEP and PM25 both increased ROS
    production in a dose-dependent manner.
    December 2009
                                                   D-34
    

    -------
           Study
    Pollutant
    Exposure
    Effects
    Reference: Bachoual   PMi0 from two Paris, France subway
    et al. (2007,1556671    sites: PER and Metro
    
    Species: Mouse       CB (Frankfurt, Germany)
    
    Cell Type: RAW 264.7  Ti02 (Calais, France)
    
                         DEP:SRM1650(NIST)
    
                         Particle Size: CB: 95 nm; Ti02:150 nm;
                         DEP: NR
    
                         RER PM10:79% <0.5 \im, 20% 0.5-1
                         pm;
    
                         Metro PM,0: 88% <0.5 \im, 11% 0.5-1
                         pm.
                           Route: Cell Culture (40,000 cells/ml)
    
                           Dose/Concentration: All particles: 0.01,
                           0.1,1,10|jg/cm2
    
                           Time to Analysis: 3,  8, 24 h
                             Cell Viability: No effects from any particulate at
                             concentrations up to 10 pg/cm2 for 24 h.
    
                             Inflammatory Effect: Exposure of cells to 10
                             pg/cm2 of RER or Metro induced time-dependent
                             increase  in TNF-a and MIP-2 protein release. This
                             effect was similar to both locations. No effect was
                             observed at low concentrations of PM10. No effect of
                             CB, Ti02  or DEP was observed.
    
                             GM-CSF or KC production: RER and Metro PM,0
                             did not induce any effect at any concentration.
    
                             Effect on Protease mRNA Expression: Exposure
                             of cells to 10 pg/cm2 RER or Metro PM10 did not
                             modify mRNA expression  of MMP-2 or -9 or their
                             inhibitors TIMP-1 and-2. MMP-12 expression
                             significantly increased after exposure to RER or
                             MetroPMi0for8h.
    
                             Effects on HO-1 Protein  Expression: Exposure to
                             10 pg/cm2 of RER or Metro PM,0 for 24 h induced
                             positive cytoplasmic staining for HO-1.
    Reference: Baulig et   WUB: Winter Urban Background
    al. (2007,1517331     Particles (obtained from Vitry-sur-
                         Seine, suburb of Paris, France)
    Species: Human
                         SUB: summer Urban Background
    Cell Line: 16-HBE14o- Particles Vitry-sur-Seine)
    
                         WC: Winter Curbside Particles,
                         SRM1648 (obtained from Porte-
                         d'Auteuil, ring road of Paris, France)
    
                         SC: Summer Curbside Particles, SRM
                         1648(Porte-d'Auteuil)
    
                         DEP: SRM 1650a (NIST)
    
                         DPI (control)
    
                         Particle Size: WUB, SUB: PM25; WC,
                         SC, DEP: NR
                           Route: Cell Culture (20,000 cells/cm2)
    
                           Dose/Concentration: 10 pg/cm2
    
                           Time to Analysis: 18 or 24 h
                              EOF: All native PM25 induced similarAR secretion
                              by bronchial epithelial cells (in decreasing order WC,
                              WUB, SC, SUB), but this release was significantly
                              greater than the release induced by DEP. (3-cellulin
                              increased with SC, WUB and WC. No data was
                              available for SUB or DEP.
    
                              Interleukins: IL-1a increased significantly with
                              WUB, WC.SC, DEP, DPI (in decreasing order). No
                              data was available for SUB. Exposure to WUB
                              caused IL-113 to increase to induction factor of over
                              2. IL-11 R a decreased  significantly with SUB.
    
                              Cytokines: Exposure to WUB caused G-CSF to
                              increase with an induction factor of over 2.Though
                              not statistically significant, TNF-R1 also increased.
    
                              Proteases: TIMP-2 decreased with WUB but
                              significantly increased with SUB. Overall, SUB
                              downregulated integrins and interleukins seen with
                              other particles while upregulating neurotrophic
                              factors, chemokine receptors and adhesion
                              molecules. MMPs were not measured.
    
                              Chemokines: CCR-3 significantly increased with
                              SUB. GRO-v and GRO-a increased with WC at both
                              18 and 24 h. DEP had no effect with GRO-a.
                              Removal of metal from  particles lowered response of
                              GRO-a.
    December  2009
                                       D-35
    

    -------
           Study
                Pollutant
                  Exposure
                      Effects
    Reference: Bayram et  DEP: (obtained from a 4JB1-type, light-  Route: Cell Culture
    al. (2006, 0884391      duty, 4 cyl, 2.74-L Isuzu diesel engine)
    Species: Human       DEP-FCS: DEP + PCS
    
    Cell Type: A549       DEP-NAC: DEP + N-acetylcystine,
                         antioxidant
    
                         DEP-A: DEP + AEOL10113, catalytic
                         antioxidant
    
                         DEP-S: DEP + SP600125, inhibitor of
                         JNK
    
                         DEP-N: DEP + SN50, inhibitor of NF-
                         kB
    
                         Particle Size: DEP: 0.4 pm (mean
                         diameter)
                                       Dose/Concentration: DEP: 0, 5,10, 50,
                                       100, 200 pg/mL
    
                                       Time to Analysis: 24, 48, 72  h
                                           Cell Growth: With 10% PCS (as a positive control),
                                           A549 cells exhibited time dependent growth. A
                                           mixture of PCS and DEP did not affect cell growth
                                           for up to 48 h. With DEP alone, cell growth was
                                           prevented from cell number reduction due to
                                           removal of serum at 48 and 72 h. A dose of 10
                                           pg/mL induced a maximum proliferation effect.
    
                                           Cell Cycle: DEP increased the percentage of
                                           serum-starved cells in S phase at 48 h. DEP
                                           decreased the percentage in GO/1 phase and G2/M
                                           phase.
    
                                           Apoptosis: DEP prevented the increase in
                                           apoptotic, serum-starved cells.
    
                                           Protein Expression: p21CIP1/WAF1 expression
                                           increased at 48 h.  DEP dose-dependently
                                           decreased this expression.
    
                                           MAC: MAC alone, at 33 mM, induced an increase in
                                           cell numbers. DEP-NAC inhibited cell numbers at 48
                                           h. DEP-NAC inhibited cell numbers in S phase; thus,
                                           cells in  GO/1  phase increased. DEP-NAC induced a
                                           further decrease of cells in G2/M phase.
    
                                           AEOL10113: DEP-A caused a dose-dependent
                                           decrease in cell numbers.
    
                                           SP600125: Alone,  SP600125 increased cell
                                           numbers at 33 mM. DEP-S decreased cell numbers.
    Reference: Becher et   SPM = suspended PM SRM-1648
    al. (2007, 0971251
                         Particle Size: 6-8 pm
    Species: Rat
    
    Strain: Crl/WKY
    
    Cell Type:  AM,
    Alveolar Type II
    
    Gender: Male
    
    Weight: 200 g
                                       Route: Cell Culture (1.5x106 cells/well AM;
                                       6x106 cells/well Type II)
    
                                       Dose: 200 pg/mL = 20 pg/cm2
    
                                       Time to Analysis: 20 h
                                           Cytokines in Macrophages: SPM increased TNF-a
                                           and MIP-2. NADPH inhibitor DPI reduced MIP-2
                                           response, whereas iNOS inhibitor 1400Wdid not
                                           affect either.
    
                                           Cytokines in Type 2 Cells: SPM increased IL-6 and
                                           MIP-2 significantly This SPM effect was inhibited by
                                           DPI, whereas!400W reduced the IL-6 response
                                           significantly.
    
                                           ROS in Type 2 Cells: SPM significantly increased
                                           ROS formation. DPI largely blocked this SPM effect.
    
                                           ROS in Macrophages: No significant increases
                                           were observed.
    Reference: Becker et   PM (Coarse, Fine, Ultrafine): Chapel
    al. (2005, 0885901      Hill, NC
    Species: Human
    
    Gender: Male and
    Female
    
    Age: 18-35 yr
    
    Cell Types: Alveolar
    Macrophages, NHBE
    Particle Size: PM-C: PM25; PM-
    F:PM01;PMUF:<0.1|jm
    Route: Cell Culture (0.5-1 xio5 cells/well
    NHBE; 2-3x105/mL AM)
    
    Dose/Concentration: NH BE: 25, 50,100,
    250 pg/mL of PM; AMs: 50 pg/mL of DEP or
    10ng/mLofLPS
    
    Time to Analysis: 18h for NHBE; overnight
    forAMs
    Cytokines: All 3 fractions induced dose-dependent
    increases in IL-8 secretion with PM-c, PM-F, PM-UF
    (in order of decreasing effects). TLR-2 antibody
    blocked these particle induced IL-8 effects.
    
    Inhibitors of Endotoxin effects and TLR-4
    activation: No effects were observed in NHBE, but
    all 3 fractions repressed the IL-6 release in AMs.
    
    TLR mRNA Expression: PM did not affect TLR-2
    mRNA in NHBEs. PM-C and PM-F induced a slight
    increase in TLR-4 mRNA in  NHBEs while PM-UF
    induced a substantial increase. PM-C increased
    TLR-2 mRNA in AMs and decreased TLR-4 mRNA
    in AMs.
    
    Induction of Hsp70: PM-C and PM-F induced
    Hsp70 in NHBE dose-dependently Hsp70 was not
    induced in AM following  particle stimulator.
    December  2009
                                                  D-36
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Becker et  PM (Coarse, Fine, Ultrafine): Chapel    Route: Cell Culture (3-5x10 cells/well
    al. (2005, 0885921
    
    Species: Human
    
    Gender: Male
    
    Age: 18-35 yr
    
    Cell Types: AM,
    NHBE
    ROFA
    
    Fe, Si, Cr Components
    
    Oct2001, Jan 2002, April 2002, July
    2002
    
    Particle Size: PM-C: 2.5-10 pm; PM-F:
    <0.1 pm; PM-UF: <0.1 pm
    NHBE; 2-3x1 Ob cells/mLAM)
    
    Dose/Concentration: NHBE: 11 pg/mLof
    PM;AM:50|jg/mLofPM
    
    Time to Analysis: 18-24 h NHBE; 18 hAM
    IL-8 Release in NHBE: PM-C and PM-UF induced
    effects. No effects from PM-F (all 4 dates).
    
    IL-6 Release in AM: All 3 fractions induced increase
    with later dates having generally lower effects.
    
    ROS (DCF): NHBE, at lower exposures, were
    observed to be more responsive to PM than AMs.
    AM exhibited highly variable results over time.
    
    ROS (DHR): NHBE cells were observed to be more
    responsive to PM than AMs. AM responsiveness to
    PM increased over 4 time periods; this was not
    observed in NHBE.
    
    Seasonal Variability: Coarse particles were more
    potent than F and UF regardless of the month, and
    the potency for PM to induce  IL-6/IL-8 production
    varied significantly. Coarse particles induced a 5-25
    fold change in IL-6 release  for AMs and a 3-6 fold
    change in IL-8 release for NHBEs.
    
    Metal Correlation to IL-6/8 induction: Fe and Si
    were positively associated with IL-6 release in AMs
    incubated with the coarse fraction. Crwas positively
    associated with IL-8 release in NHBE cells
    incubated with F or UF.
    Reference: Beck-
    Speier et al. (2005,
    1562621
    Species: Human,
    Canine (Beagle)
    
    Cell Types: Human
    AMs, Canine AM
    (CAM)
    DEP = SRM 1650a (NIST)
    
    EC = Ultrafine EC (spark discharge)
    
    P90 = Printex 90 (Carbon Black,
    Degussa)
    
    PG = Printex G (Carbon Black,
    Degussa)
    
    Particle Size: DEP: 20-40 nm; EC: 5-
    10nm;P90:14nm;PG:51 nm
    Route: Cell Culture (1x1 Ob cells/mLAM)
    
    Dose/Concentration: All particles: 1 (EC
    only), 3.2,10,32,100|jg/mL
    
    Time to Analysis: 60 min
    Phagocytosis: All particles were phagocytosed by
    CAM within 60 min.
    
    Oxidative Potential: EC showed a very high effect.
    DEP, P90 and PG had no effect
    
    Formation of Lipid Mediators: DEP, EC P90 and
    PG increased arachidonic acid and PGE2/TXB2 in
    CAM in a dose-dependent manner. Only EC
    increased LTB4 and 8-isoprostane.
    
    ROS Activation: All particles increased activity in
    canine macrophages with EC, P90 and PG
    increasing activity in a dose-dependent manner.
    DEP increased activity in canine macrophages.
    Similar results were observed human alveolar
    macrophages but only EC and P90 were tested.
    
    Particle Mass vs Particle Surface Area:
    PGE2/TXB2 effects were highly correlated with
    particle surface area.
    Reference: Bitterle et
    al. (2006, 1562761
    
    Species: Human
    
    Cell Type: A549
    C-UFP = Ultrafine carbonaceous
    particles (obtained from a spark
    discharge aerosol generator GFG
    1000,  Palas, Karlsruhe, Germany)
    
    Particle Size: 90 nm (count median
    mobility diameter)
    Route: Cell Culture (3x107 cells)
    
    Dose/Concentration: 44 + 4 ng/cm2; 87 +
    23 ng/cm2; 230 + 70 ng/cm2
    
    Time to Analysis: 6 h
    Cell Viability: Exposure to clean air resulted in a
    93.7 ±9.1% viability. Exposure to low, mid and high
    doses of C-UFP resulted in a 94.9 + 9.5% viability.
    Thus C-UFP had no effect on cell viability.
    
    Interleukins: Clean air controls induced a 2-3 fold
    increase in IL-6 and IL-8 production vs submersed
    control. U-CFP exposures induced a similar effect
    on IL-8 and  IL-6 levels.
    
    Antioxidant enzyme HO-1:  The mid dose
    increased transcription of HO-1  by 2.7 fold. There
    was no observed effect at the high dose level which
    indicates possible cytotoxicity.
    December 2009
                                                   D-37
    

    -------
           Study
                                    Pollutant
                  Exposure
                      Effects
    Reference: Blanche!
    et al. (2004, 0879821
    
    Species: Human
    
    Cell Type:  16H BE
                         PM25
    
                         (Vitry-sur-Seine, Paris, France)
    
                         DEP = SRM 1650a
    
                         CB = Carbon Black (Degussa)
    
                         TI02 (Huntsman)
    
                         Particle Size: CB: 95 nm; TI02:150 nm
    Route: Cell Culture (45,000 cells/cm')
    
    Dose/Concentration: All particles: 0.1,1,
    10, 30 pg/cm2
    
    Time to Analysis: 6,18, 24, 30 h
    Amphiregulin Expression: DEP and PM25 both
    increased AR mRNA expression from 6 to 30 h, with
    PM25 inducing higher expression levels than DEP.
    Both DEP and PM25 increased AR protein secretion.
    No observed effect for CB and Ti02.  PM25 induced
    protein secretion dose-dependently.
    
    Signal Pathways  in AR Secretion:  MAP kinase
    and tyrosine kinase inhibitors reduced effects of
    DEP and PM2 5 but p38MAP kinase inhibitor did not.
    
    Role of Oxidative Stress: N-Acetylcysteine blocked
    AR secretion following PM25. Antioxidant enzyme
    catalase had no effect.
    
    Cytokines: DEP induced a significantly  high release
    ofGM-CSF,  higher than PM25. EGFR antibody
    reduced GM-CSF  release at 0.25 pg/mL dose.
    Reference: Bonvallot   DEP: SRM 1650
    etal. (2001, 156283'
                                                           Route: Cell Culture (3x1 Ob cells)
                         OE-DEP: dichloromethane extract (2x)   Dose/Concentration: DEP, sDEP, nDEP
                                                           and CB = 10 pg/cm2
    Species: Human      of DEP
    
    Cell Type: 16HBE14o- nDEP: native DEP
    
                        sDEP: nDEP - OE-DEP
    
                        CB: Carbon Black FR103 (Degussa)
    
                        BaP: Benzo[a]pyrene
    
                        CB: 95 nm
    
                        NR
    
                        Particle Size: CB: 95 nm; DEP: NR
                                                           OE-DEP = 15 pg/mL
    
                                                           BaP = 0.25, 50 and 250 pg/mL
    
                                                           Time to Analysis: 24 h
                                           Proinflammatory Response: At 10 pg/cm , nDEP
                                           induced GM-CSF release by 4.7 fold. OE-DEP
                                           increased GM-CSF by 3.7 fold. BaP and sDEP also
                                           induced increases of CN-CSF but had smaller effect.
                                           CB had no effect.
    
                                           NF-KB Activation: nDEP and OE-DEP induced
                                           enhanced degradation of 1KB at 2-4 h and 1 h
                                           respectively. NF-KB DNA binding was enhanced by
                                           OE-DEP (15 pg/mL, peak <1 h) and nDEP (10
                                           pg/cm2, peak at 2-h with plateau till 4 h). Both OE-
                                           and nDEP enhanced NF-kB DNA binding levels
                                           were higher than BaP enhanced binding levels.
    
                                           CYP1A1 mRNA: The CYP1A1 mRNA level was
                                           markedly increased in  nDEP and OE-DEP treated
                                           cells in comparison with their respective controls.
    
                                           Radical Scavengers (decreased  ROS in situ):
                                           Increases of GM-CSF and NF-KB DNA binding by
                                           nDEP and OE-DEP was attenuated by radical
                                           scavengers.
    
                                           MAPK Activation: Increases by nDEP and OE-DEP
                                           of GM-CSF was inhibited by Erk1/2 inhibitor but not
                                           by p38 inhibitors. Both nDEP and OE-DEP triggered
                                           Erk1/2 and p38 phosphorylation. sDEP affected p38
                                           phosphorylation only.
    Reference: Brown et
    al. (2007, 1563001
    
    Species: Human,
    Mouse
    
    Cell Type:  PBMC,
    A549 (Human);
    J774A.1 (Mouse)
                         PM10 (London, England)
    
                         CM from PM10-treated human
                         monocytes
    
                         Particle Size: PM10
    Route: Cell Culture (1 xio6 cells/ml
    J774A.1; 5x106 cells/ml PBMC; 5x105
    cells/well A549)
    
    Dose/Concentration: PMi0:75 pi (10
    pg/mL);CM:250pl;tBHP:12.5pm(in
    J774);TNF:0, 500 pg, 1 ng, 10 ng
    
    Time to Analysis: tBHP:1, 2, 4 h; PM: 4 h;
    TNF:18h
    Cytokines: PM10 induced release TNF-a protein
    from PBMCs at 10 pg/mL for 4 h. Further inhibited
    by verapamil and BAPTA-AM. Calmodulin inhibitor
    W-7 had no effect. CM increased IL-8 from A549
    cells 3 fold. Verapamil, BAPTA-AM and W-7
    significantly inhibited IL-8 release induced by CM.
    
    ICAM-1: A549 cells treated with TNF-a showed
    dose-dependently effect of TNF-a on ICAM-1
    upregulation at 18 h. CM also induced upregulation.
    Verapamil, BAPTA-AM and W-7 fully inhibited CM-
    induced upregulation.
    December  2009
                                                                      D-38
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Calcabrini  PM25(Rome, Italy)
    et al. (2004, 0968651
         v	Particle Size: PM25
    Species: Human
    
    Cell Type: A549
                                       Route: Cell Culture (5^104 cells/well)        Particle Characterization: Components measured
                                                                      ,        include C-rich particles, Ca sulfates, silica, silicates,
                                       Dose/Concentration: 30, 60 pg/cm (aliquot  Fe.rich particles, metals. Carbonaceous particles
                                       ofO.1 fjg/fjl)                              made up majority of PM.
                                       Time to Analysis: 5, 24, 48, 72 h
                                                                                                    Cell Surface Changes: PM deposited on the cell
                                                                                                    surface showed dose and time-dependent increases
                                                                                                    in microvilli rearrangement and cell shape alterations
                                                                                                    without affecting apoptotic markers for up to 72 h.
    
                                                                                                    PM internalization: At 24 h with the low dose,
                                                                                                    aggregates of PM in cytoplasm or surrounded by
                                                                                                    membrane was observed. With the high dose, large
                                                                                                    particle aggregates often close to nuclear envelopes
                                                                                                    were observed.
    
                                                                                                    Cytoskeleton: At 72 h PM induced dose-dependent
                                                                                                    alterations from rearrangement/interweaving of
                                                                                                    microtubules to bundling of microtubules with some
                                                                                                    shortening/disruption.
    
                                                                                                    Cell Growth: PM decreased cell growth in a dose
                                                                                                    and time-dependent manner
    
                                                                                                    ROS: PM increased ROS at the high dose for 5 h
                                                                                                    but not at 24 h or with the low dose.
    
                                                                                                    Cytokines: PM induced TNF-a peaked at 5 h at
                                                                                                    high dose and 48 h at low dose, both ND at 72 h.
                                                                                                    PM induced IL-6 starting at 24 h thru 72 h in time
                                                                                                    and dose dependent manner.
    Reference: Cao et al.
    (2007, 1563221
    
    Species: Human
    
    Cell Type: HAEC
    NIST-DEP: collected using a diesel
    forklift and hot bag filter system. (NIST,
    Minneapolis, MN)
    
    C-DEP: obtained from a 30-kw (40 hp)
    four-cylinder Deutz BF4M1008 diesel
    engine (U.S. EPA)
    
    Organic extract fraction of particles
    
    NIST-DEP 2%
    
    C-DEP 20 %
    
    Particle Size: NR
    Route: Cell Culture (5x105 cells)
    
    Dose/Concentration: NIST-DEP, C-DEP: 0,
    12.5,25,50, 100, 200|jg/mL
    
    Time to Analysis:  1-4h
    Cell Viability: DEP had no effect.
    
    StatS: Both DEPs induced time-dependent
    phosphorylization of StatS in cytoplasm. NIST-DEP
    induced phosphorylization dose-dependently from
    12.5 to 50 fjg/mL but stayed level at 100 and 200
    pg/mL p-Stat3 induction was inhibited by antioxidant
    BHA though it was reactivated with exposure to
    H202.  Reaction induced by H202 was similar to that
    of DEP.
    
    pStatS Nuclear Transport: NIST-DEP induced
    cytoplasmic pStatS to move from cytoplasm into
    nucleus.
    
    pEGFR Dephosphorylation: After 4 h of NIST-DEP
    exposure, dephosphorylation was  inhibited for up to
    90 min.
    Reference: Chang et
    al. (2005, 0977761
    
    Species: Human
    
    Cell Type: A540, THP-
    1
    UfCB (Printex 90, Degussa)
    
    Particle Size: 14 nm
    Route: Cell Culture (7x105 cells)
    
    Dose/Concentration: 100 |jg/mL
    
    Time to Analysis: 4 h
    ROS in THP-1 and A649: UFCB increased ROS.
    NAC pretreatment blocked most of the UFCB-
    induced ROS production.
    
    VEGF in THP-1: UFCB increased VEG.  NAC
    decreased the UFCB effects below those of the
    control.
    
    VEGF in A649: Produced similar, but less marked,
    results as with THP-1.
    December 2009
                                                   D-39
    

    -------
           Study
                Pollutant
                                                     Exposure
                       Effects
    Reference: Chauhan
    et al. (2004, 0966821
    
    Species: Mouse
    
    Strain: BALB/c
    
    Cell Type: RAW
    264.7;J774A.1;
    WR19M.1
    EHC-T: total EHC-93 (Env Health Ctr,
    Ottawa, Canada)
    
    EHC-I: insoluble EHC
    
    EHC-S: soluble EHC
    
    SRM1648: urban particulate St. Louis
    (NIST)
    
    SRM1649: urban dust/organics
    Washington (NIST)
    
    VERP: fine PM25 (Vermillion, Ohio)
    
    Cristobalite: SRM  1879 (NIST)
    
    Ti02:SRM154b(NIST)
    
    Particle Size: EHC-93: 0.5 pm (median
    diameter); Cristobalite, SRM 1648,
    SRM 1649, Ti02,:NR; VERP: PM25
                                       Route: Cell Culture (15000 cells/well)
    
                                       Dose/Concentration: Particle suspensions:
                                       20, 50, 100 fjg/well
    
                                       IPS: 0-5 pg/mL
    
                                       IFN-y:0-1000U/mL
    
                                       Time to Analysis: Particles added to culture
                                       at Oh,  IPS and IFN-v added at 2 h.
                                       Parameters measured after 22 h incubation
                                       period.
    Stimulation with LPS/IFN-y: IPS and IFN-y each
    induced NO release. Combination of IPS and IFN-y
    produced larger effect in all cell lines. L-NMMA,
    NOS inhibitor, suppressed most of the NO
    production with 100 nmol/L
    
    Cellular Viability and Cytotoxicity: Exposure of
    cells to particulates did not result in overt cytotoxicity
    or excessive loss of cellular material. There was no
    correlation between the cytotoxicity of the particles
    in the surviving cells and the loss of protein mass in
    monolayers.
    
    Nitrite Production: EHC-T, EH-93-I, SRM1648 and
    SRM 1649 produced dose-dependent decreases.
    Cristobalite only decreased at higher doses. No
    effect from EHC-S, VERP or Ti02.
    
    iNOS: EHC-I, EHC-T, Crisobalite and SRM1648
    inhibited iNOS expression. Ti02 had no effect. EHC
    sol, SRM  1649 and VERP were not tested.
    Reference: Chauhan
    et al. (2005, 1557221
    
    Species: Human
    
    Cell Type: A549
    EHC-T: total EHC-93
    
    EHC-I insoluble EHC
    
    EHC-S: soluble EHC
    
    Cristobalite (Si02): SRM-1879
    
    Ti02:SRM-154b
    
    Particle Size: EHC-93: 0.4 pm (median
    physical diameter); Ti02,  Si02: 0.3-0.6
    pm
                                       Route: Cell Culture (150000 cells/flask)
    
                                       Dose/Concentration: All particles: 0,1, 4,
                                       mg/5ml
    
                                       Time to Analysis: 24 h
    Cellular Viability: Decreased after exposure to
    EHC-T, EHC-I and Cristobalite. Rate of reduction
    was not consistent across doses. EHC-S and Ti02
    had no effect on viability.
    
    ET-1: Release of ET-1 peptide decreased dose-
    dependently for EHC-T, -S and -I. Fractions of EHC-
    S and EHC-I were more potent than EHC-T. Ti02
    and Cristobalite also reduced ET-1 secretion
    although this was not consistent across the dose
    range.
    
    Cytokines: Results showed no detectable amounts
    ofGM-CSF, IL-1P or TNF-a in cell culture
    supernatants. IL-8 increased dose-dependently with
    EHC-T, EHC-I and Cristobalite.
    
    VEGF: VEGF significantly increased dose-
    dependently with EHC-T, EHC-S and Cristobalite.
    EHC-S induced a significant decrease in VEGF.
    
    Gene Expression: mRNA levels for preproET-1
    reduced at 24 h for all particle types. EHC-S induced
    a significant decrease in ET-1 expression at this high
    dose. ECE-1 mRNA expression increased with EHC-
    T and EHC-I. Other particles had no effect. ETaR
    mRNA  increased with EHC-T, EHC-S, and Ti02 in
    biphasic manner where the highest expression of
    mRNA was seen at the  middle dose levels. EHC-S
    had no effect. ETbR mRNA increased with a low
    dose of EHC-T and decreased with a high dose of
    EHC-T. EHC-S, EHC-I and Cristobalite induced an
    increase of ETbR. Ti02  induced a significant
    decrease.
    
    Proteases: mRNA levels for MMP-2 reacted
    similarly to preproET-1.  mRNA levels for TIMP-2 was
    significantly induced with EHC-I. EHC-T and EHC-S
    induced small effects.
    Reference: Cheng et
    al. (2003, 1563371
    
    Species: Human
    
    Cell Type: A549
    DEP-h: DEP with high sulfur
    DEP-LS:DEP with low sulfur
                                       Route: In Vitro Cellular Exposure (Exhaust
                                       flow-through cell culture with air-cell-
    GEP: gasoline engine exhaust particles interface, exhaust diluted 10-15x with 8^10
    Primed cells pretreated with TNF-a     cells/mL)
                         Particle Size: DEP-h: 15.9 nm; DEP-
                         LS: 17.7 nm;GEP: 8.3 nm
                                       Dose/Concentration: DEP (total): 1.5-
                                       3.5x106 particles/cm3; GEP (total): 1-2x106
                                       particles/cm3; TNF-y: 5ml (25 ng/ml)
    
                                       Time to Analysis: 60-360  min
    IL-8: DEP-h induced a 3 fold increase in IL-8 than
    that of the control. DEP-LS also induced increases.
    Primed cell cases had higher levels (10x) than
    unprimed when exposed to DEP-LS. DEP-h induced
    higher levels of IL-8 than DEP-LS. This response
    lasted for up to 6 h. GEP induced a statistically
    insignificant increase of IL-8 in unprimed cells. Wth
    primed cells, GEP induced levels of IL-8 that
    exceeded those of DEP-h and  DEP-LS. This
    response lasted for 1-2 h.
    December 2009
                                                   D-40
    

    -------
    Study
    Reference: Chin et al.
    (2003, 1563401
    Species: Rat, Human
    
    Cell Line/Type: RAW
    264.7, MHS (Alveolar
    Macrophage Cell
    Line), A549
    
    
    
    Pollutant
    CB: (N339, with benzo[a]pyrene
    absorbed on surface. Manufactured in
    Cabot, Boston, MA)
    
    BaP
    Benzo [a] pyrene 1, 6-quinone: BP-1,6-
    Q (obtained from NCI, Kansas City,
    MO)
    Particle Size: CB 0.1 pm (mean
    diameter)
    Exposure
    Route: Cell Culture
    Dose/Concentration :
    
    CB: 1, 2, 4|jg/mL
    BaP: 2 pg/mL
    BP-1,6-Q:1 pM
    
    Time to Analysis: 1 -24 h
    
    Effects
    HO-1 mRNA Expression: In RAW2647, HO-1
    mRNA levels increased with 2 and 4 pg/mL at 2 h.
    Increases continued to 8 h and declined by 24 h.
    BaP had no effect. BP-1.6-Q increased HO-1 mRNA
    after 1 h and was maintained until 8 h. In A549 and
    MHS, HO-1 mRNA increased after 1 h, peaking at 8
    hinA549and4hinMHS.
    HO-1 Protein Expression: An increase of protein
    was observed from 4-8 h in RAW2647.
    AP-1 : Increases in binding activity were observed in
                                                                                                     RAW 264.7 cells at 2 h.
    Reference: Churg et
    al. (2005, 0882811
    
    Species: Rat
    
    Strain: SD
    
    Weight: 250 g
    
    Cell Type: Epithelial
    Cells of Tracheal
    Explants
    EHC93 (Ottawa Urban Air Particles)     Route: Cell Culture
    TiFe = Iron-loaded fine Ti02 (obtained
    from Aldrich Chemicals, Milwaukee,
    Particle Size: EHC-93: 3-4 pm
    (MMAD); TiFe: 0.12 +1.4 pm
    (geometric mean diameter)
    Dose/Concentration: EHC-93, TiFe: 500
    pg/cm2
    
    Time to Analysis: 1, 24 h. Some
    experiments (referred to as 2 h) explants
    transferred to different dish and incubated
    for additional hour. Pre-treated with
    Inhibitors/Chelatorsfor2h.
    Activation of NF-KB: Both particle types increased
    nuclear translocation of NF-KB. TiFe and EHC-93
    increased NF-KB 1.5 fold at 1 h. TiFe increased NF-
    KB 3.5 fold at 2 h. EHC-93 increased NF-KB more
    than 2 fold. Ti02 by itself did not increase NF-KB at
    any exposure  duration.
    
    Morphological changes in tracheal epithelial
    cells: No evidence of dust particles was observed
    (EHC-93 or Ti02) in the epithelial cell cytoplasm at 2
    h. No evidence of morphologic cell damage from
    particles was observed.
    
    Colchicine: Treatment with colchicine did not
    prevent NF-KB activation.
    
    Inhibitors/Activators: Tetramethylthiourea (TMTU)
    (membrane-permeable active oxygen scavenger),
    Deferoxamine (redox-inactive metal chelator), PPS
    (Src inhibitor) AG1478 (epidermal growth factor
    receptor inhibitor) prevented NF-KB activation in
    both EHC93 and TiFe exposed-cells. Iron-containing
    citrate extract  of both dusts increased NF-KB
    activation in both EHC93 and TiFe exposed-cells.
    Reference: Courtois et  PM (SRM 1648)
    al. (2008, 1563691
            	(63% in, 4-7% , mass fraction >1 %: Si,
    Species: Rat          S, Al, Fe, K, Na)
    Strain: Wstar
                          UF carbon black (FW2, P60)
                                        Route: Cell Culture
    
                                        Dose/Concentration: 100, 200 pg/mL
    
                                        Time to Analysis: 24 h incubation
    Cell Line: Dissected    Particle Size: SRM 1648 mean
    intrapulmonary arteries  diameter 0.4 pm; ultrafme carbon black:
    from rats used in        FW2-13 nm, P60- 21 nm
    corresponding in vivo
    experiments
                                             NO: Generally, Ach-induced relaxation in
                                            intrapulmonary arteries decreased, Ach-induced
                                            cGMP accumulation decreased, and relaxation  by
                                            SNP or DEA-NO also decreased.  UF carbon black
                                            did not affect NO responsiveness.
    
                                            Oxidative Stress, Inflammatory: Dexamethasone
                                            prevented SRM 1648-induced impairment of the Ach
                                            relaxation response but antioxidants did not. TNF-a,
                                            MIP2, IL-8 increased. ROS was not affected.
    Reference: Dagher et
    al., (2007, 0975661
    
    Species: Human
    
    Cell Type: L132
    (Normal Lung
    Epithelial Cells)
    LC10, LC50 = PM25
    (collected Jan-Sept in Dunkerque,
    France)
    
    Particle Size: cumulative frequency:
    0.5 pm: 34%; 1 pm: 64%; 1.5 pm: 79%;
    2 pm: 87%; 2.5 pm: 92%; 5 pm: 98%;
    10|jm:100%
    Route: Cell Culture (3x106,1.5x106,
    0.75x106cells/20mL)
    
    Dose/Concentration: LC10:19 pg/mL;
    LC50: 75 pg/mL
    
    Time to Analysis: 24, 48 or 72 h
    p66 Protein: Phosphorylation of p65 increased in
    PM-exposed L132 cells in dose-dependent manner.
    
    kBo Protein: Phosphorylated iKBa protein
    concentrations increased in cytoplasm with both
    particle types at all time points.
    
    p66 and p60 DMA: p65 DNA binding increased at
    24 h with LC10 and LC50, at 48 h with LC10, and at
    72 h with LC10 and LC50. p50 DNA binding
    increased at all time points with LC10 and LC50.
    December 2009
                                                    D-41
    

    -------
           Study
                Pollutant
                              Exposure
                       Effects
    Reference: Dai et al.
    (2003, 0879441
    
    Species: Rat
    
    Strain: SD
    
    Weight: 250 g
    
    Cell Type: Tracheal
    Explants
    EHC-93 (Environmental Health Center,
    Ottawa)
    
    DEP: SRM 1650a (NIST)
    
    Particle Size: EHC-93: 3-4 pm
    (MMAD); DEP 1.55 ± 0.04 pm (CMD)
                Route: Cell Culture
    
                Dose/Concentration: ECH, DEP: 500
                pg/cm2
    
                Time to Analysis: Exposed for 1 h.
                Parameters measured following a 7 day
                incubation period.
    Hydroxyproline: EHC93 induced an almost 3 fold
    increase in explant hydroxyproline. DEP increased
    tissue hydroxyproline 2.5 fold.
    
    Procollagen: EHC-93 doubled gene expression of
    procollagen. Procollagen gene expression could be
    fully inhibited by SN50, TMTU or treatment of the
    PM with DFX. Treatment of explants with p38 or
    ERK (inhibitors) had no effect on procollagen
    expression. DEP induced an increase in procollagen
    gene expression but this increase was completely
    prevented by SN50 and MAP kinase inhibitors
    (SB203580 and PD98059). Neither TMTU or DFX
    has any effect.
    
    TGF01: Treatment of explant with EHC93
    approximately doubled gene expression for TGF|31.
    Treatment with SN50, TMTU and fetuin (TGFfS
    antagonist) blocked increase. DFX, MAP kinase
    inhibitors (SB203580 and PD98059) had no effect.
    DEP roughly doubled TGF|31 expression.SN50 and
    MAP kinase inhibitors (SB203580 and  PD98059)
    fully blocked this effect. TMTU and DFX had no
    effect.
    Reference: Doherty et Ratios of: V: Fe; Al: Fe; I
    al. (2007, 0965321
    Species: Rat
    
    Strain: NR8383
    
    Cell Types: AMs
    V = sodium vanadate (NaV03)
    
    Al = aluminum chloride hexahydrate
    (AICI3)
    
    Mn = manganese chloride tetrahydrate
    (MnCI2)
    
    Fe = ferric chloride hexahydrate (FeCI3)
    
    Ratios based on PM25 measurements
    from NYC, LA and Seattle
    
    Particle Size: Metals from PM25
    samples
    : Fe         Route: Cell Culture (2x105 cells/ml)
    
                Dose/Concentration: Fe = 16 pmol
                (equivalent to urban NYC 500 pg PM25); V
                and Mn tested in molar rations of 0.02 to 0.4
                relative to Fe; Al tested in molar ratios of
                0.125 to 8  relative to Fe.
    
                Time to Analysis: 20 h
    IRP: Addition of V increased IRP activity 5 to 9 fold.
    Though there was no seeming dose responsivity,
    IRP activity remained strongly elevated over the
    range of V:Fe ratios tested. Addition of Mn only
    resulted in an effect at 0.1 molar ratio (two-fold), not
    at higher or lower ratios. Al resulted in peak
    increases of 5 fold at molar ratios 2 while declining
    to 2 fold at molar ratios 4 and 8.
    
    Cytotoxicity: Al was cytotoxic at molar ratios of 4
    and 8. All other Al, V, Mn ratios had no effect.
    
    Mixtures: The combination of metals tested at NYC
    PM ratios and V drove all the Fe transport activity.
    Combinations of V+Mn and V+AI increased activity
    more than V:Fe alone.
    Reference: Doornaert, DEP: SRM 1650 (NIST)
    et al. (2003, 1564101
                         CB: (Sigma, France)
    Species: Human
    
    Cell Line/Type:
    16HBE140-; P-HBE
    DPC: Dipalmitoyl phosphatidylcholine
    (positive control)
    
    0.5 um
    
    Particle Size: NR
                Route: Cell Culture
    
                Dose/Concentration: DEP and CB: 1-100
                pg/mL
    
                Time to Analysis: Parameters measured
                24, 48, 72 h post exposure. 1-HBE Cell
                Deadhesion Capacity: 24 h, evaluation of
                detachment performed every 5min for 40
                min after. Cell V\found  Repair Capacity: 24 h,
                repair evaluated 3.5, 7, 24  h after.
    Cytotoxicity: DEP was cytotoxic at 100 pg/mL at all
    time points in a time-dependent manner. CB and
    DPC Cytotoxicity was substantially lower but
    significant at 72 h.
    
    Phagocytosis: 1-HBE cell levels that were in
    contact with DEP or CB or have phagocytized those
    particles increased in a dose-dependent manner.
    DEP induced greater levels of cell contact and
    phagocytosis than CB.
    
    F-actin: Only DEPs were engulfed by F-actin
    stained cell fragments.
    
    Actin CSK Stiffness: DEP (5, 20,100 pg/mL)
    induced net dose-dependent decrease in
    cytoskeleton stiffness and a dose-dependent
    decrease in actin cytoskeleton stiffness. CB
    produced no significant decrease.
    
    Adhesion Molecules: DEP induced a concomitant
    reduction of both CD49 (a3) and CD29 (Ł1) integrin
    subunits and a decrease in level of CD44 (HBE cell-
    cell and cell-matrix adhesion molecule) at both 20
    and100|jg/mL
    
    Proteases: DEP also induced an isolated decrease
    in MMP-1 expression without change in tissue
    inhibitor of TIMP-1 or TIMP-2 at 100 fjg/mLCB
    produced no change or insignificant results.
    
    1-HBE Cell Deadhesion Capacity: DEP exposure
    induced a dose-dependent amplification of cell
    detachment at 5 min of incubation and onward.
    
    Cell Wound Repair Capacity: DEP inhibited wound
    repair/wound closure in a dose-dependent manner.
    December 2009
                                                   D-42
    

    -------
           Study
                Pollutant
                  Exposure
                                                              Effects
    Reference: Dostert et  Asbestos
    al. (2008, 1557531
    Species: Human
    
    Cell Line/Type: THP1,
    monocyte-derived
    macrophages (MM)
    Silica
    
    DEP
    
    CSE: cigarette smoke extract
    
    MSU: monosodium urate crystals
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: Asbestos: 0.1, 0.2
    mg/mL; Silica: 0.1, 0.2, 0.25, 0.5 mg/mL;
    DEP: 0.2, 0.25, 0.5 mg/mL; CSE: 5%, 10°/<
    in solution mg/mL; MSU: 0.1, 0.2 mg/mL
    
    Time to Analysis: 1, 3, 6h
                                           IL-10: Increased levels of IL-1|3 with asbestos and
                                           silica were observed in THP1 at 6 h. CSE and DEP
                                           had no effect. MM also had increased levels with
                                           asbestos, silica and MSU at high dose levels only.
    
                                           Caspase-1: Asbestos increased caspase-1 activity.
    
                                           ROS: Asbestos doses in THP1 exhibited an
                                           increase in ROS formation.
    Reference: Doyle, et
    al. (2004, 0884041
    
    Species: Human
    
    Cell Type: A549 from
    non-smoking  adults
    BD: 1,3-butadiene, known carcinogen
    
    Acrolein: photochemical and NO
    product of BD in atmosphere
    
    Acetaldehyde: photochemical and NO
    product of BD in atmosphere
    
    Formaldehyde: photochemical and NO
    product of BD and ISO in atmosphere
    
    ISO: isoprene, 2-methyl analog of BD
    
    Methacrolein: photochemical and NO
    product of ISO in atmosphere
    
    Methyl vinyl ketone: photochemical and
    NO product of ISO in atmosphere
    
    Particle Size: NR
    Route: Environmental Irradiation (smog)
    Chambers
                                           Cytotoxicity: ISO+NO and BD+NO induced small
                                           increases of LDH inA549. However, ISO+NO+light
                                           and BD+NO+light increased LDH levels 4-6 fold
    Dose/Concentration: 50 ppb NO; 200 ppbV indicating photochemical products of ISO and BD
                                           are highly cytotoxic. LDH levels of each combination
                                           were equivocal.
    ISO, BD
    Time to Analysis: Exposed to gases for 5 h.
    Analysis 9 h post exposure.
                                                                                                    IL-8 Protein: Methacrolein, methyl vinyl ketone and
                                                                                                    formaldehyde (products of ISO) increased IL-8
                                                                                                    protein levels significantly. ISO+NO had no effect.
                                                                                                    BD photochemical products (acrolein, acetaldehyde
                                                                                                    and formaldehyde) also increased IL-8 protein, more
                                                                                                    than doubling the photochemical products induced
                                                                                                    by ISO. BD+NO had no effect.
    
                                                                                                    IL-8 mRNA: IL-8 mRNA expression also increased
                                                                                                    with photochemical products of ISO and BD but did
                                                                                                    not reach a statistically significant level.
    Reference: Duvall et
    al. (2008, 0979691
    
    Species: Human
    
    Cell Type: Airway
    Epithelial Cells
    PM-F, -C, -UF
    
    Particles collected from: Seattle, WA
    (PM-S); Salt Lake City, UT (PM-SL);
    Phoenix, AZ (PM-P); South Bronx, NY
    (PM-SB); Hunter College, NY (PM-
    Sterling Forest, NY (PM-SF)
    
    Particle Size: Coarse: >2.5 pm; Fine:
    <2.5|jm;UFP:<0.1 pm
    Route: Cell Culture (100,000 cells/cm')
    
    Dose/Concentration: 5 mg/ml
    
    Time to Analysis: 1, 24 h post exposure
                                           Particle Characterization: PM-HR, PM-SL and PM-
                                           S contained the highest UF, F, and C concentrations.
                                           PM-SB and PM-HR had similar F and C
                                           concentrations. Sulfate was highest in PM-F for all
                                           sites except in PM-SB and PM-HR. V\food
                                           combustion was highest in PM-SL,  PM-S, PM-P. Soil
                                           dust was highest in PM-SL and PM-S.
    
                                           IL-8: PM-UF induced a greater increase in IL-8 than
                                           other types of PM except PM-P. PM-UF is
                                           associated with vanadium, lead, copper, sulfate. PM-
                                           F-HR caused the greatest increase followed by PM-
                                           SB. PM-F-SF and PM-F-P was least effective. PM-C
                                           also caused an increase in IL-8 levels and was
                                           associated with vanadium and EC.
    
                                           COX-2: PM-F-S induced the greatest increase in
                                           COX-2 expression. Other PM-F sites induced  similar
                                           increases. UF PM had no effect. PM-C, associated
                                           with EC, induced increases.
    
                                           HO-1: PM-F-SF induced the greatest increase in
                                           HO-1. PM-F-SL was the least effective. UF PM had
                                           no effect. PM-C, associated with copper,  barium and
                                           EC, caused an  increase.
    Reference: Dybdahl et DEP: SRM 1650 (NIST)
    al. (2004, 0890131
            	Particle Size: 90 nm (MMAD)
    Species: Human
    
    Cell Type: A549
                                       Route: Cell Culture (105cells/mL)
    
                                       Dose/Concentration: 0,10, 50,100, 500
                                       pg/mL
    
                                       Time to Analysis: 2, 5, or 24 h
                                            Cytokines: DEP induced dose-dependent increases
                                            of IL-1a, IL-6, IL-8 and TNF-a at 24 h. Cytokines
                                            increased between 4 and 18 fold at the highest DEP
                                            dose as compared to controlled cells. DEP also
                                            increased IL-6 mRNA expression levels in a dose
                                            and time-dependent manner.lL-6 mRNA levels
                                            increased 14 fold at 24 h, 8 fold at 5 h, and 2 fold at
                                            2h.
    
                                            Cell Viability: DEP exposure did not decrease cell
                                            viability at any dose tested.
    December  2009
                                                   D-43
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Fritsch et
    al. (2006, 1564521
    
    Species: Mouse
    
    Cell Type: RAW 264.7
    MAF02: incinerator fly ash (collected by Route: Cell Culture (1 xio  cells/well)
    electrostatic precipitation in commercial
    municipal waste incinerator facility)
    composition representing 12% of total
    mass (mg/g):
    
    Fe (9.1); Pb (23.3); Zn (75.7); C (7.5)
    
    Particle Size: 165 nm (modal value)
    Dose/Concentration: 6.3-188 pg/cm for
    Toxicity; 2.6, 6.5,13.2 pg/cm2 for
    ArachidonicAcid; 13.2 pg/cm2 for MARK
    Pathway; Other doses noted in Effect of
    Particles
    
    Time to Analysis:  1,2.5, 5, 24 h
    Toxicity: Viability decreased from 99% to 18% at
    62.5-188 pg/cm2. Lower doses had  no effect.
    
    Arachidonic Acid: At 2.5 h, AA level increased 2
    fold for 6.5 pg/cm2 and 6 fold for 13.2 pg/cm2.  No
    increase was observed after 5 h.
    
    MAPKs: Cells pretreated with PD98059, an inhibitor
    of MEK-1, inhibited AA liberation due to MAF02
    treatment of 13.2 pg/cm2
    
    COX-2: A time-dependent increase  of COX-2 protein
    expression was exhibited at 2.5 and 5 h.
    
    ROS: A dose-dependent increase in ROS formation
    was observed at concentrations greater than 31.3
    pg/cm after 3 h.
    
    GSH: There was an observed increase of production
    at 20 h. Doses greater than 60 pg/cm2 reduced total
    glutathione.
    
    HO-1: There was an observed dose-dependent
    increase in expression at 4 h.
    Reference: Fujii et al.  PMi0: EHC-93 (Ottawa, Canada)
    (2002,036478)
    
    Species: Human
    
    Cell Type: HBEC
    (from current
    smokers), AMs, Co-
    Culture: AMs+HBEC
    
    Age: HBEC: 48-70 yr
                                       Route: Cell Culture (HBEC: 2.5-3x 106
                                       cells/well); (AMs: 1.0x107 total)
    
                                       Dose/Concentration: 100, 500 pg/mL
    
                                       Time to Analysis: 2, 8, 24 h
                                            Viability: Over 90% of HBEC were viable after a 24
                                            h exposure of up to 500 pg/mL of PM. AMs
                                            incubated with and without 100 pg/mL saw no
                                            significant difference in viability.
    
                                            Cytokine mRNA: TNF-a, GM-CSF,  IL-lp, IL-6, LIF,
                                            OSM and IL-8 mRNA expression increased in co-
                                            culture with 100 pg/mL at 2 and 8 h. In AMs, TNF-a,
                                            IL-1|3, IL-6 mRNA expression increased with 100
                                            pg/mLat2h. INHBECs, IL-lp and LIF increased
                                            with 100 pg/mL at 2 h. HBECs added to AMs
                                            exposed to PM10, further increase in mRNA of IL-1|3,
                                            LIF and IL-8.
    
                                            Cytokine Protein: In co-culture and AMs, significant
                                            increase in protein production of GM-CSF, IL-8, IL-
                                            lp, IL-6 and TNF-a in dose-dependent manner. GM-
                                            CSF and IL-6 production significantly higher in co-
                                            culture then AM or HBEC alone.
    
                                            Bone Marrow: Co-culture instillation of
                                            supernatants increased circulating band cell counts
                                            at 6 and 24 h with 100pg/mL
    Reference: Fujii et al..  PM10:EHC93 (Ottawa, Canada)99%
    (2001, 1564551        <3.0um
    Species: Human
    
    Cell Type: HBEC from
    current smokers
    
    Age: 48-70 yr
    Particle Size: PM10( 99% < 3.0 pm)
    Route: Cell Culture (2.5-3x1 Ob cells/dish)
    
    Dose/Concentration: 10,100, 500 pg/mL
    
    Time to Analysis: 2, 8, 24 h
    Phagocytosis: 18.6% of cells engulfed particles
    when exposed to 100 pg/mL. Over 90% remained
    viable.
    
    Cytokine mRNA: LIF mRNA increased dose-
    dependently at 2 h but declined at 8 and 24 h. GM-
    CSF increased dose-dependently at 8h and peaked
    at 24 h. IL-1a increased at 2 h, increased dose-
    dependently at 8 h and peaked at 24 h. M-CSF,
    MCP-1, IL-8 were unaffected.
    
    Cytokine Protein: LIF, GM-CSF, IL-1|3 and IL-8
    increased dose-dependently. Soluble fraction of 100
    pg/mL PMio did not affect cytokine production.
    December 2009
                                                   D-44
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Garcon et
    al. (2006, 0966331
    
    Species: Human
    
    Cell Type: L132
    PM25 (collected in Dunkerque, France
    for 9mo, Jan-Sept)
    
     Particle Size: PM25- 0-0.5 pm
    (33.63%), 0.5-1.Opm (30.61%),  1.0-1.5
    pm (14.33%), 1.5-2.0 pm (8.69%), 2.0-
    2.5 pm (4.89%), >2.5 pm (7.87%)
    Route: Cell Culture: 3x10b cells/20ml (24 h);
    1.5x106cells/20ml(48h); 0.75x106
    cells/20ml (72 h)
    
    Dose/Concentration: 18.84, 37.68, 56.52,
    75.36,150.72 pg/mL; LC10-18.84 pg/mL;
    LC50- 75.36 pg/mL
    
    Time to Analysis: 24, 48 or 72 h
    Cytotoxicity: PM induced dose-dependent
    (R2 =.9907) cytotoxic effect in proliferating L132
    cells.
    
    LDH: Increase at 72 h with 56.52 and 75.36 pg/mL.
    
    Oxidative Stress: A decrease in MDF activity was
    observed at all exposure levels at 24, 48, and 72 h
    (72-h <5 % of control). MDA levels showed increase
    concentration after 72 h, both LC10 and LC50. LC10
    and LC50 saw an increase in SOD activity at 24 h;
    LC50 saw a decrease in activity after 48 and 72 h. 8-
    OHdG and PARP exhibited increases at all time
    points with LC10 and LC50.
    
    Inflammatory Response: Increases of TNF-a
    concentration was exhibited at 24 h at LC50, and at
    48 h and 72 h at LC10 and LC50. iNOS activity
    increase at all time points at LC10 and  LC50.NO
    concentration exhibited increases at all time points
    after exposure to LC10 and LC50.
    Reference: Geng et
    al. (2005, 0966891
    
    Species: Rat
    
    Strain: Wistar Kyoto
    
    Tissue/Cell Type:
    Lung macrophages
    BPM: Blowing PM25; PM collected from  Route: Cell Culture
    Wuwei City, Gansu Province, China
    (Blowing days correspond to desert
    storm days)
    NPM: Non-blowing (normal) PM25
    
    Particle Size: PM25
    Dose/Concentration: 0, 33,100, 300 pg/mL
    
    Time to Analysis: 4 h
    Cytotoxicity: Dosages greater than 150 pg/mL
    decreased cell viability.
    
    Plasma Membrane Fluidity: Dose-dependent
    decrease had no effect on membrane lipid
    hydrophilic region.
    
    Plasma Membrane Permeability: LDH enzyme
    activity and extracellular AP activity increased dose-
    dependently, indicating increased membrane
    permeability, but this was only statistically significant
    at 300 pg/mL dose. NPM may affect some
    parameters at 100 pg/mL Overall, NPM induced a
    slightly higher increase than BPM.
    
    Intracellular Ca2+: A dose-dependent increase was
    observed.
    
    Lipid Peroxidation (TBA): An increase was
    observed only at 300 pg/mL
    
    Antioxidant (GSH): A decrease was observed only
    at 300 pg/mL
    Reference: Geng et
    al. (2006, 097026)
    Species: Rat
    Strain: Wistar Kyoto
    Tissue/Cell Type:
    Lung macrophages
    DPM: dust storm samples; PM
    collected from Baotou City, Inner
    Mongolia, China in March 2004
    NPM: normal PM
    Particle Size: PM25
    Route: Cell Culture
    Dose/Concentration: 0, 33, 100, 300 pg/mL
    Time to Analysis: 4 h
    Cytotoxicity: MTT reduction assay revealed a
    significant decrease in cell viability at 150 pg/mL and
    300 pg/mL LDH enzyme activity significantly
    increased at 150 and 300 pg/mL
    GSH levels: Significant decreases were seen in
    cellular GSH levels and increases in TBARS levels
    in both groups with a 300 pg/mL dose.
                                                                                                   Plasma Membrane Activity: In the plasma
                                                                                                   membrane, Na, K-ATPase were significantly
                                                                                                   inhibited. Ca *Mg *-ATPase were unaffected.
    
                                                                                                   Plasma Membrane Lipid Fluidity: Results indicate
                                                                                                   that DPM could increase the surface fluidity of
                                                                                                   membrane lipid.
    
                                                                                                   Intracellular Ca2+: A dose-dependent increase in
                                                                                                   free intracellular Ca2+ levels was observed.
    Reference: Ghio et al.
    (2005, 0882721
    
    Species: Human
    
    Cell/Tissue Type:
    BEAS-2B
    FAC: ferric ammonium citrate
    
    (component of ROFA)
    
    VOS04: vanadyl sulfate
    
    (component of ROFA)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 100 pM FAC -
    preexposed before metal compounds or oil
    fly ash
    
    50 pM VOS04 - preexposed before metal
    compounds or oil fly ash
    
    100|jg/mLROFA
    
    Time to Analysis: 0-1 h, 4 h
    IRE DMT1: FAC increased mRNA and protein
    expression for -IRE DMT1. VOS04 decreased
    mRNA and protein expression for-IRE DMT1. +IRE
    DMT1 unaffected by any treatment.
    
    Metal transport: Uptake of iron increased after pre-
    exposure to FAC and decreased after pre-exposure
    to VOS04. Pre-exposure to FAC again increase the
    uptake of both iron and vandium. VOS04 induced
    opposite effect, decreasing  Fe uptake.
    
    ROS: Increased acetaldehyde, indicating increased
    oxidative stress. ROS decreased with FAC
    pretreatment. ROS increased with VOS04
    pretreatment.
    December  2009
                                                   D-45
    

    -------
           Study
                                     Pollutant
                  Exposure
                       Effects
    Species: Rat
    
    Strain: SD
    Reference: Gilmour et  Coal Fly Ash
    al. (2004, 0574201     MU = Montana Ultrafine
                         MF = Montana Fine
                         MC = Montana Coarse
                         KF = V\fest Kentucky Fine
                         KC = V\fest Kentucky Coarse
    Cell/Tissue Type: AM  Cog| combus(ion usjng g |aboratory.
    
                         scale down-fired furnace rated at
                         50kW. Montana subbituminous coal
                         and western Kentucky bituminous coal
    
                         Particle Size: Coarse:  >2.5 pm; Fine:
                         <2.5|jm;UFP:<0.2|jm
    Route: Cell Culture (2x1 Ob cells/ml)
    
    Dose/Concentration: 125 pg/mLor250
    pg/mL
    
    Time to Analysis: 4 or 24 h
    LDH: Mid and high doses of Montana ultrafine
    particles showed significant increase after 4 h
    exposure vs control. Other particle types had no
    effect. After 24 h, LDH level was not statistically
    significant between particles tested and control.
    
    Cytokines: Treatment with Montana ultrafine
    particles resulted in a significant production increase
    of TNF-a. MIP-2 showed increases in all the fine and
    ultrafine treatments, with Montana ultrafine and W.
    Kentucky fine PM showing the highest increases. IL-
    6 increased with Montana ultrafine particles although
    there was some variability and the increases were
    not statistically significant.
    Reference: Gilmour et  PM10: Collected from the Marylebone
    al. (2005, 0874101     and Bloomsbury monitoring sites in
                         London, UK
    Species: Human
    
    Cell/Tissue Types:
    monocyte derived
    macrophages,
    HUVECs, A549,
    16HBE
                         Particle Size: PIvl-
                                                             Route: Cell Culture
    
                                                             Dose/Concentration: 50 |jg/mL
    
                                                             Time to Analysis: 4 h, 6 h, 20 h
                                            IL-8: PM10 at 50 pg/mL induced a significant
                                            increase in IL-8mRNA and protein expression in
                                            PMM and 16HBE at 6 and 20h. A less substantial
                                            increase was also observed in A549.
    
                                            Procoagulant Activity: PMi0 induced a significant
                                            decrease in macrophage mediated clotting time in
                                            16HBE. Other cell types were unaffected.
    
                                            Annexin V Binding: At 100 pg/mL, PM10 induced a
                                            significant increase in binding macrophages at 4 and
                                            20 h. There was no effect at 50 pg/mL
    
                                            Tissue Factor mRNA Expression: Expression was
                                            increased in macrophages at 6 h only.
    
                                            tPA Expression: mRNA expression decreased at
                                            6 h. Protein expression decreased at 4 h and 20 h in
                                            a dose-dependent manner.
    
                                            TF Expression: TF mRNA expression increased in
                                            a dose-dependent manner at 6 h in HUVECs.
                                            Protein levels also increased at 4 h but declined to
                                            basal levels by 20 h.
    Reference: Gilmour et  PM10: Collected from the Marylebone
    al. (2003, 0969591     and Bloomsbury monitoring sites in
                         London, UK
    Species: Human
    
    Cell/Tissue Type:
    A549
                         TSA
    
                         H202
    
                         NAC
    
                         Mannitol
    
                         Provided by Sigma Chemical, Poole,
                         UKorGIBCO-BRL, Paisley, UK
    
                         Particle Size: PM10
    Route: Cell Culture
    
    Dose/Concentration: PM10:100 pg/mL;
    TSA: 100 ng/mL; H202: 200 pM; NAC and
    Mannitol: 5mM
    
    Time to Analysis: 24 h
    IL-8: PMio, TSA and H202 treatment induced an
    increase of IL-8. Concomitant exposure of TSA with
    PM10 or H202 significantly increased IL-8 release
    when compared to PM10 or H202 alone. IL-8 mRNA
    expression with PMio or H202 exposure and TSA
    coincubation caused significant increases. Silver
    staining of PCR products indicated that the IL-8
    gene promoter was associated with acetylated  H4
    following TSA, PM10 and TNF treatment.
    
    H4: PMio exposure significantly increased
    acetylation levels of H4 over controls. Increased
    acetylated H4 was mediated by PM10 in a dose-
    dependent manner. Treatment with PMio and H202
    increased HAT activity associated with H4 by 245%
    and 166% respectively. Significant increases in
    acetylation of H4 following treatment of cells with
    TSA, PM,o and H202 for 24 h was observed.
    PM10induced HAT activity was significantly
    decreased in the presence of NAC and mannitol.
    Nuclear presence of HDAC2 protein was
    significantly reduced by exposure to both HDAC
    inhibitor and PMio. There was a decreasing trend in
    HDAC2 gene expression following TSA and PM10
    treatment.
    
    NF-KB: The activation of the transcription factor NF-
    KB was enhanced following the  inhibition of HDAC
    with TSA and by treatment with
    December 2009
                                                                        D-46
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Graffetal.  PM
    (2007, 1564881
    
    Species: Human
    
    Cell/Tissue Type:
    HAEC
    -UF: ultrafine
    
    -F: fine
    
    -C: coarse
    
    Particles collected from Seattle, WA (-
    S), Salt Lake City, UT (-SL), Phoenix,
    AZ (-P), South Bronx, NY (-SB), Hunter
    College, NY (-H), Sterling Forest, NY (-
    SF)
    
    Particle Size: UF:<0.1 pm; F: 0.1-2.5
    pm;C: 2.5-10 pm
    Route: Cell Culture
    
    Dose/Concentration: 250 |jg/mL
    
    Time to Analysis: 6 h, 24 h
    Gene Expression: PM-UF, PM-F, and PM-C both
    upregulated and downregulated genes in the HAECs
    though downregulation was far more common for all
    the three PM fractions. PM-F affected the greatest
    number of transcripts, followed by the UF and C
    fractions.
    
    IL-8: mRNAexpression increased, with PM-F-S
    having the greatest impact. Aluminum, strontium,
    manganese and potassium were highly associated
    with expression. Wood combustion was moderately
    associated.
    
    HOX-1: mRNA expression increased, with PM-F-SF
    having the greatest impact. Potassium, manganese,
    strontium and wood combustion were highly
    associated with expression. Aluminum and
    vanadium were moderately associated.
    Reference: Gualtieri et TD: Tire debris extracted in methanol,
    al. (2005, 0978411     constituent of PM,0
    Species: Human
    
    Cell Type: A549
    (generated by spinning a new
    automotive tire against abrasive
    surface)
    
    Particle Size: 10-80 pm
    Route: Cell Culture
    
    Dose/Concentration: 10, 50, 60, 75 pg/mL
    
    Time to Analysis: 24, 48, 72 h
    Cytotoxic Effect: Treated cells presented inhibitory
    effect on reduction of MTT which appeared to be
    dose and time-dependent. A statistically significant
    reduction was observed at 48 and 72 h. Trypan blue
    showed a significant PM lethality as well as a dose-
    dependent increase in mortality.
    
    DMA Damage: At 24 and 72 h, DNA damage
    increased dose dependently in damaged and ghost
    cells.
    
    Cell Cycle Analysis: At 24 h, TD extract-treated
    cells presented a significant increase in the
    percentage of cells in G1 phase when com pared
    with control. This increase was associated with a
    decrease in the percentage of cells in S phase. At 48
    and 72 h, the increase in percentage of cells in G1
    was associated with a decrease in the percentage of
    cells in both S and G2/M phases. Cells exposed to
    TD extracts presented changed morphology.
    Modifications most obvious at 72 h. The highest dost
    produced increased vacuolization in cytoplasm and
    apoptotic nuclear images.
    Reference: Hetland et
    al. (2005, 0878871
    
    Species: Rat
    
    Gender: Male
    
    Strain: Crl/Wky
    
    Cell Type: AMs
    PMC = Coarse
    
    PMF = Fine
    
    -A = Amsterdam
    
    -L=Lodz
    
    -R = Rome
    
    -0 = Oslo
    
    Coexposures PAH, Fe, Al, Zn, Cu, V
    
    Particle Size: PMC: 2.5-10 pm; PMF:
    0.2-2.5 pm
    Route: Cell Culture (1.5x10b cells/well)
    
    Dose/Concentration: 50,100 pg/mL PM
    
    Time to Analysis: 20 h
    IL-6: PMC from all cities exhibited increases in IL-6
    release with spring and summer roughly equal and
    both inducing higher levels than the winter PMC. For
    the Spring and Summer samples, PMC-L exhibited
    the highest IL-6 releases (440% and 460%
    respectively) followed by Rome, Adam/Oslo, and
    Oslo/Adam. For the winter samples, Rome  and
    Amsterdam induced higher IL-6 levels (340% and
    300% respectively) than Lodz and Oslo (165% and
    160%). The fine fractions did not induce any
    significant cytokine release.
    
    TNF-a: PMC from all cities increased TNF-a release
    with 50 pg/mL generally inducing a slightly higher
    increase than 100 pg/mL
    
    Constituent Correlation: Levels of Fe, Al, Zn, Cu
    and V as well as PAH (total and fractions) showed
    no correlation with IL-6  release.
    
    Endotoxin Correlation with IL-6 release: A
    confirmatory test revealed no correlation.
    December 2009
                                                   D-47
    

    -------
           Study
                Pollutant
                                                                          Exposure
                                                                                                 Effects
    Reference: Hetland et
    al. (2004, 0975351
    
    Species: Rat, Human
    
    Cell Type: Alveolar
    Macrophages (Rat),
    A549
    
    Strain: Wky/NHsd
    
    Gender: Male
    
    Weight: 180-230 g
    AMC = Ambient Coarse
    
    AMF = Ambient Fine
    
    AMUF = Ambient Ultrafine
    
    (AM samples taken at a suburban site,
    without a dominating PM source, near
    Utrecht,  Netherlands)
    
    Road  PM: PM10, (collected in a road
    tunnel with predominating road
    abrasion due to use of studded tires in
    Trondheim, Norway)
    
    Particle Size: AMC: 2.5-10 pm; AMUF:
    <0.1 pm
                                                            Route: Cell Culture (1 xlOb cells/well)
    
                                                            Dose/Concentration: 0,100, 200, 400, 600,
                                                            800,1000pg/mL
    
                                                            Time to Analysis: 20h (Type 2 cells); 40h
                                                            (A549 cells)
                                                                              IL-8: All 3 AM fractions showed dose-dependent
                                                                              increases in A549 cells until 600 pg/mL; at that
                                                                              concentration, levels declined. AMC showed the
                                                                              most pronounced decline which correlates with
                                                                              decreased viability. Road PM showed a near linear
                                                                              response until 1000 pg/mL, whereas DEP plateaued
                                                                              at600|jg/mLinA549.
    
                                                                              MIP-2: AMC  and AMUF had no effect on Type 2
                                                                              cells. DEP induced increases at 200 pg/mL,
                                                                              whereas Road PM induced the strongest increase,
                                                                              peaking at 600 pg/mL  in  Type 2 cells.
    
                                                                              IL-6: AMC induced increases at 100 pg/mL in Type
                                                                              2, but levels declined below normal at 200 pg/mL.
                                                                              AMUF induced a decline of IL-6 levels. Road PM
                                                                              induced significant increases in Type 2.  DEP had a
                                                                              slight effect. AM fractions induced increases in A549
                                                                              cells, peaking at 600 pg/mL with AMF DEP and
                                                                              Road PM induced a dose-dependent increase.
    
                                                                              Cell Survival: AMC showed major effects at 200
                                                                              pg/mL  in Type 2. AMUF showed effects at 400
                                                                              pg/mL Road PM and DEP showed a gradual
                                                                              decline from  75% to 50% at 800 pg/mL in Type 2. All
                                                                              AM fractions induced a decrease in viability after
                                                                              600 pg/mL in A549 with AMC inducing a larger
                                                                              decrease than AMUF and AMF; AMUF and AMF
                                                                              induced similar levels. Road PM and DEP had no
                                                                              effect on A549.
    
                                                                              Apoptosis: AMC elicited a marked induction of
                                                                              apoptosis 200 pg/mL in Type 2 cells. AMF showed a
                                                                              dose-dependent increase in A549. Other AM
                                                                              fractions showed some slight increases in both cell
                                                                              types. Statistical significance was reached for all
                                                                              particles except for Road PM.
    Reference: Holder et
    al. (2008, 0933221
    
    Species: Human
    
    Cell Type: 16HBE14o
    DEP: generated from a single cylinder
    diesel engine using , commercial
    certified #2 diesel fuel
    
    Copollutants: NOX7 ppm, C020.1%
    
    Particle Size: Suspension: 223 nm
    (mean diameter); All: 122 nm (mean
    diameter)
                                                            Route: Suspension (1 xio cells/cm 1, Air
                                                            Liquid Interface (All, 1xl05 cells/cm)
    
                                                            Dose/Concentration: Suspension: 0.13,
                                                            0.24,1.88, 2.5, and 12.5 pg/cm2; All: 1
                                                            g/cm3 (total number of particles: 2.3x107
                                                            particles/cm2)
    
                                                            Time to Analysis: Exposure for 6 h.
                                                            Parameters measured 20 h post-exposure.
                                                                              All vs Tracheal Bronchial (TB) Deposition: The
                                                                              TB region deposition is 1.5 nominally x All, but
                                                                              particle diameter deposited in the TB was 62 nm
                                                                              (geometric mean diameter) as compared to the
                                                                              particle deposition in the All, measuring 260 nm.
    
                                                                              Inflammatory Response: Suspended DEP
                                                                              decreased viability at concentrations of 2.5 pg/cm or
                                                                              higher. IL-8 release  (corrected for viability) increased
                                                                              at concentrations of 1.88 pg/cm2 or higher in a dose-
                                                                              dependent manner.  IL-8 exhibited intermediate
                                                                              levels of secretion between in vitro levels of 0.25
                                                                              and 1.88 pg/cm2. No statistically significant results
                                                                              were observed in ALL Viability for ALI was near
                                                                              100%(75%uncorrected).
    Reference: Huang et
    al. (2003, 0873761
    
    Species: Human,
    Mouse
    
    Cell Type: BEAS-2B,
    RAW 264.7
                         PMC: PM coarse
    PMSM: PM submicron
    
    Collected between September-
    December 2000 from 4 ambient
    monitoring stations in Taiwan that
    represented background, urban, traffic,
    and industrial sites
    
    Particle Size: PMC: 2.5-10 pm; PMF:
    1-2.5pm; PMSM: <1 pm
                                       Route: Cell Culture (5x1 Ob cells/mL)
    
                                       Dose/Concentration: All PM: 50, 70,100
                                       pg/mL
    
                                       Time to Analysis: BEAS-2B: 8h; RAW
                                       264.7:16 h
                                                                                                   Viability: None of the PM fractions affected cell
                                                                                                   viability.
    
                                                                                                   IL-8: Only PMSM induced a significant IL-8 increase
                                                                                                   in BEAS-2B. IL-8 response was associated with a
                                                                                                   combination of Mn and Cr (R2 = 0.28). Response
                                                                                                   was also correlated with nitrate, although
                                                                                                   significance disappeared when 1 extreme nitrate
                                                                                                   value was removed.
    
                                                                                                   Lipid Peroxidation: Only PMSM enhanced lipid
                                                                                                   peroxidation in BEAS-2B, correlating with both
                                                                                                   elemental and.
    
                                                                                                   TNF-a: In RAW264.7, PMSM increased TNF-a
                                                                                                   production. Polymixin pretreatment significantly
                                                                                                   reduced TNF-a levels for all 3 PMs which indicates
                                                                                                   an endotoxin role in macrophage response. TNF-a
                                                                                                   production (after polymixin pretreatment only) was
                                                                                                   associated with Cr and Fe content.
    December 2009
                                                   D-48
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Hutchison  PMi0: Samples collected for 7 day
    et al. (2005, 0977501   during closure (-C) and reopening of
                         steel plant (-R)
    Species: Mouse
    
    CellLine:J774.1A
    PMT: PM total (aqueous sonicate)
    
    PMS: PM soluble aqueous
    
    PMI: PM insoluble aqueous
    
    Particle Size: PIvl-;
    Route: Suspension
    
    Dose/Concentration: 500 |jl (estimated
    concentrations of 112, 143,156,180, 233,
    255 pg/1 ml water)
    
    Time to Analysis: 4 h
    Particle Characterization: Reopening of the plant
    showed a significant increase in the total and acid
    extractable metal content of PM. Aqueous
    extractable metal content did not change. Soluble
    zinc, copper and manganese also increased
    significantly post reopening. Iron was the most
    abundant in acid extractable metals and increased
    greatly at the reopening.
    
    TNF-a: PMT-R and PMT-C induced a statistically
    significant increase. Treatment with chelation agent
    reduced effect to control levels.
    Reference: Imrich et
    al. (2007, 1558591
    
    Species: Rat
    
    Gender: Female
    
    Age: 12-14 wk
    
    Cell Type: AM
    UAP:SRM 1649 (positive control)
    
    Ti02: Particle control
    
    CAPs (Boston, MA)
    
    All cells primed with IPS
    
    Coexposure with MAC,
    dimethylthiourea (DMTU), H202 or
    catalase
    
    Particle Size: CAPs: <2.5 pm; UAP:
    PM25; Ti02: ~1 pm
    Route: Cell Culture (2x105 cells/well)
    
    Dose/Concentration: Caps 100 pg/mL;
    UAP: 50 or 100 pg/mL; IPS 250 ng/mL;
    MAC, DMTU: 2,10, 20 mM; Catalase: 1, 5,
    10 mM; H202 0-50 pm/hr
    
    Time to Analysis: 18-20h
    TNF-a: DMTU at 20 mM reduced TNF in LPS-
    primed cells in control and UAP-treated groups.
    MAC at 20 mM reduced TNF release but this was
    not statistically significant. Catalase significantly
    inhibited TNF in control and  UAP-treated groups.
    CAPs (especially the insoluble portion) significantly
    increased TNF unless co-exposed with NAC, DMTU
    or catalase. All three reduced levels back to around
    basal levels. DMTU was particularly effective at
    diminishing TNF release. H202 increased TNF
    release in CAPs-exposed cells. Ti02 had no
    increased ability to induced cytokine release when
    mixed with H202.
    
    Cell Death: Viability decreased substantially when
    exposed to H202 + CAPs. The soluble fraction of
    CAPs showed to be more effective with H202 than
    the insoluble portion. Ti02 had no significant effect.
    
    NO: Some CAPs induced slight increases when
    mixed with H202. No difference was observed
    between soluble and insoluble portions of CAPs.
    
    DFO: DFO at 0.05 mM completely inhibited
    oxidation induced with soluble CAPs + H202.
    Insoluble CAPs + H202 was  also DFO-sensitive.
    DFO was ineffective against the insoluble CAPs
    induction of TNF and MIP-2.
    Reference: Ishii et al.
    (2004, 0881031
    Species: Human
    Cell Type: A549
    (collected from 6
    lobectomy or
    pneumonectomy
    smokers), HBEC
    EHC-93:PM10 (obtained from
    Environmental Health Directorate,
    Ottawa, Ontario, Canada)
    Particle Size: PM10
    Route: Cell Culture (1x!07 cells)
    Dose/Concentration: 100 |jg/mL
    Time to Analysis: 3, 6, 24 h
    Cytokines: TNF-a, IL-lp, GM-CSF, IL-6, and IL-8
    levels were significantly increased in A549 cells.
    mRNA Expression: MCP-1, ICAM-1 and IL-8
    mRNA expression increased in untreated AM
    supernatants at 3 h. Only the MCP-1 levels were
    statistically significant at 3 h. Levels declined by 6 h.
    When A549 cells were exposed to PM10 exposed
    AM, levels of RANTES, TNF-a, ICAM-1, IL-1|3, and
    LIF increased. Except for RANTES mRNA, these
    differences were less in the 6 h samples. VEGF
    increased as well, but this increase was not
    statistically significant.
                                                                                                     TNF-a and IL-1p-neutralizing Antibodies:  L-1p
                                                                                                     antibody alone or in combination with TNF-a
                                                                                                     significantly reduced expression of all eight mRNAs.
                                                                                                     Combinations for some mRNAs reduced expression
                                                                                                     by up to 1/2. This effect was not observed when
                                                                                                     A549 was treated with the control AM.
    
                                                                                                     Transcription Factor Binding Activity: Binding of
                                                                                                     AP-1 and Sp1 increased when A549 treated with
                                                                                                     supernatants from PMio-exposed AM, but not from
                                                                                                     control AM.
    December 2009
                                                    D-49
    

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           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Ishii et al.
    (2005, 0961381
    Species: Human
    Cell Type: AMs
    (obtained from 10
    EHC-93: PM10 (obtained from
    Environmental Health Directorate,
    Ontario, Canada)
    Particle Size: PM10
    Route: Cell Culture (HBEC: 2.5-3.0x1 06
    cells; AM: 1 xio7 cells; co-culture of
    AM/HBEC: 5x1 06 cells)
    Dose/Concentration: 100 |jg/mL
    Ti me to Analysis: 2, 24 h
    mRNA Expression After 2 h Exposure: AM or
    HBEC exhibited no effect. In contrast, co-culture
    increased expression of MIP-lp, GM-CSF, M-CSF,
    IL-6, MCP-1 and ICAM-1-mRNA.
    mRNA Expression After 24 h Exposure: AMs
    exhibited no effect. HBEC increased levels of GM-
    smokers who stopped
    smoking 6 wk prior),
    HBEC
                                                                               CSf, LIF and ICAM-1. Co-culture, on the other hand,
                                                                               increased expression of MIP-lp, GM-CSF, M-CSF
                                                                               and ICAM-1 mRNA.
    
                                                                               Protein Levels: AM and HBEC both increased GM-
                                                                               CSF, IL-6 and MIP-1 p release into the supernatant.
                                                                               Co-culture effect was not additive but synergistic
                                                                               (i.e., higher than expected). MCP-1 levels did not
                                                                               increase significantly. Co-culture appeared to
                                                                               decrease protein levels for both the control and PM
                                                                               values. M-CSF levels increased for co-culture only.
    
                                                                               Surface Expression of ICAM-1: Upon 24 h
                                                                               exposure to PM, HBEC exhibited an increase in
                                                                               expression. Expression in AMs were not affected by
                                                                               2 h PM stimulation.
    
                                                                               ICAM-1 Inhibitors: IgG or anti-CD! 1b antibody was
                                                                               unaffected in co-culture.
    Reference: Jalava et
    al. (2005, 0886481
    UPM: SRM1649a (Washington, DC)
    
    DEP:SRM1650(NIST)
    Species: Mouse
                         EHC-93: Ottawa dust (Environmental
    Cell Type: RAW 264.7  Health Center, Ottawa, Canada)
    
                         HFP-00: Pooled ambient air PM25
                         sample from Helsinki, Finland
    
                         M-UPM: methanol extract of UPM
    
                         Particle Size: SRM 1649a, SRM 1650,
                         EHC-93: NR; HFP-00: PM25
    Route: Cell Culture (5x105 cells/ml)
    
    Dose/Concentration: 150 |jg/mL
    
    Time to Analysis: Methanol treatment of
    PM samples: 24 h; Exposure to ambient PM
    samples: 2, 4, 8,16, or24h.
    TNF-a: All the PM samples increased TNF-a.
    
    Cell Viability: SRM1649a exhibited the most
    cytotoxicity, followed by HFP-00 and EHC-93.
    Methanol significantly affected cytotoxicity of the
    EHC-93 sample only.
    
    Cytokines: TNF-a concentrations in the cell culture
    medium significantly increased at all time points
    between 2 and 24 h. The highest increase was seen
    in EHC-93. IL-6 production also increased at
    different levels with the highest increase observed in
    EHC-93. No response was observed for IL-10.
    
    Cell Viability: Duration of exposures had no
    significant effect on any of the samples. A 2 h
    exposure time was sufficient to induce the typical
    reductions in cell viability.
    Reference: Jalava et
    al. (2006, 1558721
    
    Species: Mouse
    
    Cell Type: RAW 264.7
    PM: Collected east of Helsinki, Finland
    between Aug 23 and Sept 23, 2002
    
    Divided in 12 groups (4 sizes by 3
    exposure types):
    
    -S: seasonal average
    
    -W: wildfire
    
    -M: mixed
    
    -B: blank
    
    Particle Size: PMio-25;PM25-1; PMi.02;
    PMo.2
    Route: Cell Culture (5x106 cells/mL)
    
    Dose/Concentration: 15, 50,150 and 300
    pg/mL
    
    Time to Analysis: 24 h
    Particulate Mass Concentrations in HVCL Size
    Ranges: The largest increase of PM concentrations
    was observed in PM^.
    
    NO: All 12 samples increased NO production when
    compared to corresponding unexposed controls.
    Peaks were observed at 150  pg/mL, except in PMi.
    0.2'
    
    Cytokines: All 12 samples increased TNF-a and IL-
    6 production. PM10.2.5 and PM25.i produced a much
    larger response than PM^and PM02. IL-6
    production for PM02 was not measured.  MIP-2
    production also increased with similar trends.
    
    Cytotoxicity: All 12 samples induced dose-
    dependent decreases in  cell viability. PM10-25 were
    the least active inducers of apoptosis while PMO.2
    showed the highest activity (4-17% of apoptotic
    cells).
    December 2009
                                                   D-50
    

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           Study
                                      Pollutant
                                                                           Exposure
                       Effects
    Reference: Jalava et
    al  (2007  096950)
     'v    --
    Species:  Mouse
    
    Cell Type: RAW2647
                         Urban background PM
                                                             Route: Cell Culture (5x10  cells/ml)
                         PM10, PM2 5, and PM0.2 collected from   Dose/Concentration: 15, 50, 150, 300
                         6 European cities during different times  pg/mL
                             e year from October 2002 to July
                         -D: Duisburg (Fall)
    
                         -P: Prague (Winter)
    
                         -A: Amsterdam (Winter)
    
                         -HR: Helsinki (spring),
    
                         -B: Barcelona (spring)
    
                         -AT: Athens (summer)
    
                         Particle Size: PMi0: 2.5-10 pm; PM25:
                         0.2-2.5 pm; PM02: <0.2 pm
    PM Characterizations: The highest mass
    concentrations of PM10 and PM0 2 were measured in
    Athens. Prague had the highest PM25
    concentrations.
    
    NO: All PM fractions induced statistically significant
    NO production in  macrophages. PM25 -P and PM25 -
    AT produced significantly larger responses, though
    all samples at 150 and 200 pg/mL induced
    statistically significant  production. When compared
    to the other PM0 2 samples, -P and -HR produced
    significantly larger responses.
    
    Cytokines: PM10  showed average cytokine
    production to be 7.8 fold and 83 fold for TNF-a, and
    4.4 fold and 530 fold for MIP-2 when compared to
    PM25 and PM02 respectively. PM10 induced
    statistically significant  increases in production of
    TNF-a, MIP-2 and IL-6. PM25, with exception of
    Prague, caused significant increases in cytokines.
    PM02-A and -AT showed small yet statistically
    significant increases in TNF-a. An increase in MIP-2
    was observed with -P and -HR. IL-6 increased
    significantly with PMi0 and slightly with PM2 5. In the
    PMo.2 range, only  the -A and -AT samples caused a
    small, statistically significant TNF- a production.
    MIP-2 production  was only detected from the -P and
    -HR samples. PM0 2 effects on  IL-6 response were
    negligible.
    
    Cytotoxicity: The average cytotoxicity of PM10 and
    PM25 were roughly equal, but PM02 were less
    cytotoxic with the  exception of -P. The dose-
    response trends for most of the samples were
    linearly declining,  with PM10 and PM2 5 exhibiting
    statistically significant declines in viability.
    Reference: Jimenez et PMi0: Collected from London and
                         Edinburgh air particulate monitoring
                         stations.
    al. (2002, 1566101
    
    Species: Human
    
    Cell Type/Line: A549,
    THP-1, Mono Mac 6
    (DSMZ)
                         Ti02:Tioxide Europe (London, UK) and
                         Degussa-Huls (Cheshire, UK)
    
                         UFTi02: Tioxide Europe (London, UK)
                         and Degussa-Huls (Cheshire, UK)
    
                         Particle Size: PM10, Ti02: 200 nm;
                         UFTi02: 20 nm
                                                             Route: Cell Culture (110,625 cells/well)
    
                                                             Dose/Concentration: PM10, Ti02, UFTi02:
                                                             100 pg/mL; TNF-a: 10ng/mL
    
                                                             Time to Analysis: 4 h
    NF-KB and AP-1 DMA Binding: NF-KB DNA binding
    increased in PM10 and TNF-a exposed macrophages
    by 9.5 and 12 fold. NF-KB activity remained
    unaltered in Ti02 and UFTi02 exposed
    macrophages.
    
    IL-8: Cells treated with PMio conditioned media
    increased transcription binding of NF-kB to IL-8
    promoter sites.  Increases were observed in gene
    expression after exposure to TNF-a and PMi0. Ti02
    or UFTi02 had no effect. Increases observed in IL-8
    production with PM10.
    
    IL-8 Promoter CAT Activity: PM10 media increased
    CAT expression by 65% over control. No differences
    observed with Ti02 or UFTi02 media.
    
    Neutrophil Chemotaxis: PMio conditioned media
    induced a 2.3 fold increase compared to control.
    
    TNF-a and IL-1p Production: PM1? media
    increased TNF-a and IL-1|3 production. No increases
    were observed in Ti02 and UFTi02 media.
    December 2009
                                                                         D-51
    

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           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Jung et al.  Soot Particles: Generated using a co-   Route: Surrogate Lung Fluid
    (2006, 1324211
    
    Species: N/A
    
    Type: Surrogate Lung
    Fluid
    flow, laminar, diffusion flame system
    
    CB (Degussa)
    
    PM25: Collected using IMPROVE air
    pollution samplers
    
    Particle Size: Soot: 185 nm; CB: 25
    nm, PM25
    Dose/Concentration: Soot: 0-30 mg; CB: 5-
    10 mg; PM25: 50 or 100|jg/mL
    
    Time to Analysis: Parameters measured
    continuously over 2 h.
    OH Radical Formation: Formation occurred with
    linear dependence on soot mass. Average response
    was 0.89 nmol OH produced per mg of soot.
    Formation also occurred with soot + hydrogen
    peroxide. Hydrogen peroxide alone did not form OH
    radicals.
    
    Fe: Average Fe concentration in soot particles was
    305 + 172 nM. Observed negative correlation
    between amount of Fe and amount of OH radical
    formation. DSF inhibited iron-induced increase in
    OH radical formation.
    
    Carbon Black: OH radical generation by carbon
    black was significantly less than soot. OH generation
    by CB was observed to be linearly proportional to
    PM mass, but CB was much less efficient at
    generating the OH radical.
    
    PMis: A high variability in the increase of OH
    radicals was observed with PM25. Pretreatment with
    DSF partially blocked OH radical production, but a
    significant level remained. This may be due to PM2 5
    containing high levels of Fe and Cu.
    Reference: Kafoury
    and Madden (2005,
    1566171
    
    Species: Mouse
    
    Cell Type: RAW 264.7
    DEP: SRM 1975 (purchased from
    NIST, Rockville, MD)
    
    BAY11 -7082, NF-KB inhibitor
    (coexposure)
    
    IL-1B: obtained from Santa Cruz
    Biotechnology (Santa Cruz, CA)
    
    Particle Size: DEP: 0.3 pm (mean
    diameter)
    Route: Cell Culture (3-4x1 Ob cells)
    
    Dose/Concentration: DEP 25,100, or 250
    fjg/mL;IL-1IJ:100ng/mL
    
    Time to Analysis: DEP: 4 h pre-treated with
    BAY11-7082for1.5h;IL-1|3:4h
    TNF-a: DEP induced a significant release of TNF-a
    at 100 and 250 pg/mL dose-dependently. Exposure
    at 25 |jg/mL had no effect. IL-113 containing PM
    samples at 100 pg/mL also resulted in a significant
    release of TNF-a.
    
    NF-KB Binding Activity: Treatment of RAW264.7
    with BAY11-7082 significantly inhibited IL-1|3-
    induced TNF-a release. Similar effects observed
    with DEP-induced TNF-a release.
    
    Apoptosis: Inhibition of NF-kB binding activity by
    BAY11-7082 resulted in DEP-induced apoptotic
    response. Without  BAY11-7082, apoptosiswas not
    induced even at the DEP dose of 250/|jg/mL for 4 h.
    The control, U937 cells with campothecin, induced
    apoptosis.
    Reference: Karlsson
    et al. (2006, 1566251
    
    Species: Human
    
    Cell Type: A549,
    Monocytes (isolated
    from heparinized
    whole blood)
    PM
    
    (W1: wood burning in old-type boiler;
    W2: wood burning in modern boiler;
    P: wood pellets burning in pellets
    burner; T1: PM10 tire debris with
    studded tires and ABT pavement;
    T2a: PM10 tire debris with studded tires
    and ABS pavement; T2b: PM25 tire
    debris with studded  tires and ABS
    pavement; T3: PMi0 tire debris with
    friction tires and ABS pavement;
    St: PM10 from busy street in Stockholm,
    Sweden; Su: PMi0 from platform of
    subway station in Stockholm)
    
    Particle Size: W: NR, T1, T2a, T3, St,
    Su: PM10, T2b: PM25
    Route: Cell Culture
    
    Dose/Concentration: Suspension: 40
    pg/cm2; Culture: 100 pg/cm2 (1 ml/well)
    
    Time to Analysis: Suspension: 4 h; Culture:
    18 h
    PM Characterization: Boiler emitting PM-W1 led to
    4 times higher emission of particles when compared
    to PM-W2 and 8 times higher emissions when
    compared to PM-P. Total concentration and CO was
    substantially higher in the old-type wood boiler.
    
    Effects with Filter Fibers: No increase of DNA
    damage was observed compared to the water
    control. Filter fibers led to the induction of cytokines
    in human macrophages.
    
    Genotoxicity: All particulate samples induced DNA
    damage in A549 cells. PM-Su exhibited the most
    genotoxicity and induced 4-5 times more DNA
    damage than others.
    
    Cytokines on Glass Fiber Filters: PM-W2 induced
    a significant increase in IL-8. PM-St induced the
    highest increases of IL-6,  IL-8, and TNF-a.
    
    Cytokines on Teflon Filters: PM-2a and PM-2b
    samples caused significant increases of IL-6,  IL-8,
    and TNF-a.
    December 2009
                                                    D-52
    

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           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Katterman  PM: Oils: OAAF, Oil Q, Oil III, NF2
    et al. (2007, 0963581
                         PM: Coal Germany and Ohio
    Species: Rat
                         Diesel particulates: ZODDA (doped with
    Cell Type/Line: RLE-  Zn), ZSDDA (doped with Zn and S): S:
    6TN (Alveolar         PMs washed in solution; F: Fresh
    Epithelial Cell Line)     samples; L: Leached
    
                         AI203, Fe203, Si02, Ti02, ZnO also
                         tested
    
                         Particle Size: NR
                                        Route: Cell Culture (cytotoxicity: 50,000
                                        cells/well; SEM: 25,000 cells)
    
                                        Dose/Concentration: Oils 0.2 mg/mL;
                                        Coals 0.7 mg/mL; Diesel 0.01 mg/mL; AI203
                                        0.5 mg/mL; Fe203 0.7 mg/mL; Si02 0.7
                                        mg/mL; Ti02 0.7 mg/mL; ZnO 0.05 mg/mL
    
                                        Time to Analysis: 24 h
                                            Metabolic Activity: For oils comprised of 3/4 fresh
                                            and 1/4 leached, metabolism decreased. Coals
                                            (fresh and leached) had no effect. ZODDA-F and
                                            ZSDDA-F both induced decreases in activity.
                                            ZSDDA-L had no effect.
    
                                            Cellular Morphology: PM-S had a minimal effect.
                                            PM-F induced widespread cell damage.
    
                                            Constituent Differences between PM-F and PM-
                                            L: In oil samples Cu, Ti and Ca salts were removed
                                            upon washing. Fe, Al, Si remained constant.
    
                                            Grinding Effects: Coal toxicity increased upon
                                            grinding, whereas diesel PM toxicity decreased upon
                                            grinding.
    
                                            Metal Oxide Effects: Only Si02, and ZnO (much
                                            higher at lower concentrations than other metal
                                            oxides) decreased  metabolic activity. Fresh, washed
                                            and sonicated samples exhibited similar results.
                                            Grinding only affected Ti02 (increase) and ZnO
                                            (decrease).
    Reference: Kendall et
    al. (2004, 1566341
    
    Species: Human
    
    Tissue Type: BALF
    (obtained by
    bronchoscope from 6
    nonsmokers and 3
    smokers)
    PM25 sample sites; 2 schools in Bronx,
    NY, 6 background urban, 6 urban
    roadside. Sampling occurred 24 h/day
    for 12 days.
    
    Particle Surface Chemistry: 79-87%
    carbonaceous material (Ch, COO, C-
     0,N)), 10-17% 0 (01s), 1.5-4% N
     NH4, N-C, N032'), 0.6-1 %S, and 0.3-2
    % Si.
    
    Only N03 - higher in roadside samples.
    
    NH4 and N03 - correlated with NO and
    NOX in air but not N02.
    
    Particle Size: PM25
    Route: BALF interaction
    
    Dose/Concentration: 5-10 ml of 0.5 M NaCI
    or BALF
    
    Time to Analysis: Filters treated with BALF
    for4h
    Saline Washing: Removed particles and decreased
    NH4, N03, 0 and S relative to C1.
    
    BALF treatment (XPS): PM2$ surfaces interacted
    strongly with BALF within hours of contact. Specific
    surface components of PM2 5 immersed in BALF
    were desorbed while biomolecules from BALF were
    adsorbed to particles. N-C on the PM surface
    increased 3 fold for smokers and 4 fold for
    nonsmokers (range 1.4-7.4). This is  most likely
    related to protein-like adsorption on PM. Treatment
    also induced a slight increase in COO and
    decreases in NH4, N03, 0 and S.
    
    ToF-SIMS - Organics: Particle loading and surface
    hydrocarbons  showed  a linear correlation. Loss of
    hydrocarbons  from PM25 surface averaged 55% (10-
    75) after undergoing saline and BALF washes.  In
    only 3/12 samples BALF removed less hydrocarbon.
    BALF treatment increased the amino acid and
    phospholipid content of the PM25 surface.
    
    ToF-SIMS - Inorganic: Saline washing appeared to
    increase Al and Si but with extreme variability; this
    increase was not statistically significant. Both saline
    and BALF washing decreased NH4 and  Na levels to
    a similar extent. BALF washing did not affect Al or
    Si.
    Reference: Kim et al.
    (2005, 0884541
    
    Species: Human
    
    Cell Type/Line:
    BEAS-2B
    Zn2*
    
    Particle Size: NA
    Route: Cell Culture
    
    Dose/Concentration: 15, 50,100 pmol
    
    Time to Analysis: 1-20h
    Cell Viability: At 50 pM for 20 h, no apoptosis was
    induced.
    
    IL-8: At 12 h, IL-8 increased in dose-dependent
    manner. At 15 or 50 pM, Zn2* increased protein 1.6
    and 4.6 fold respectively. IL-8 mRNA expression
    increased dose-dependently, reaching statistical
    significance at 2 h and continuing until 4 h.
    
    EGFP (adenoviral IL-8 promoter): Levels
    increased 2.4 fold with 50 pM Zn2*.
    
    Proteases: With 50 pM Zn2*, phosphorylation of
    MAPKs ERK, JNKand p38 increased by 15 min and
    continued increasing up to 2 h. Pre-exposure of
    inhibitors of MEK, JNK, before Zn2* exposure
    caused inhibition ofZn-induced IL-8 mRNA and
    protein production. Inhibitor of p38 had no effect.
    Dephosphorylation of ERK and JNK was partially
    inhibited with exposure to Zn *.
    December 2009
                                                    D-53
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Kleinman   UF1: Utrecht 1 Fine (urban freeway)
    et al. (2003, 0879381
         v	UC1: Utrecht 1 Coarse
    Species: Rat
    
    Strain: Wistar Kyoto,
    F344
    
    Age: 22-24 mo, 10wk
    
    Cell Type/Line: AM
    UF2: Utrecht 2 Fine (urban, freeway,
    light industrial)
    
    UC2: Utrecht 2 Coarse
    
    SRM 1650
    
    SRM 1648
    
    Particle Size: UF1: 0.2-2.5 pm; UC1:
    2.5-10 pm;UF2: 0.2-2.5 pm; UC2: 2.5-
    10pm
    Route: Cell Culture (10b cells/well at 10b
    cells/ml)
    
    Dose/Concentration: 1.2 to 1200 ng/106
    cells
    
    Time to Analysis: 4,18 h
    Macrophage PMA-stimulated respiratory burst
    activity: SRM 1648 and 1650 induced dose-
    dependent decreases approaching 0 at 50 -100
    pg/10 cells. Large dose-dependent decreases from
    old rat AMs exposed to fine PM exposure were
    followed by young rat AMs exposed to fine PM.
    However, no age-related effects were statistically
    significant.
    
    Free radical production: All coarse particles
    depressed free radical production in a semi-dose-
    dependent manner,  with UC2 exhibiting more
    potency than UC1.  Both fine particles also showed
    dose-dependent responses but UF1 and UF2
    responses were greater than the control at 3 pg/106
    cells.
    
    PM Characterization: Ratios between coarse and
    fine PM were similar for metals tested (Al, Fe, Mn,
    Zn). Al was higher in coarse samples and Zn higher
    in fine PM, although large variability was observed.
    Fe and Mn results were roughly equivalent for all
    samples.
    Reference: Kocbach   PMW: Wood smoke particles           Route: Cell Culture (1 xio cells/ml)
    et al  (2008 1988741
                         Collected from conventional Norwegian  Dose/Concentration: 30-280 pg/mL
    Species: Human      wood stove burning birch
                                                             Time to Analysis: 2, 5,12 h
    Cell Type/Line: THP-1  PMT+: Traffic-derived particles;
                         collected from road tunnel in winter
                         when studded tires were used
    
                         PMT-: Traffic-derived particles;
                         collected from road tunnel in summer
                         without studded tires
    
                         DEP: SRM2975
    
                         Porphyr: fine grain syenite porphyry
                         (prepared bySINTEF, Trondheim,
                         Norway)
    
                         Polymyxin B Sulphate (endotoxin
                         inhibitor)
    
                         Particle Size: PMVV PMT, DEP: NR;
                         Porphyr 8 pm (mean)
                                                                               Particle Characterization: PMT+ contained a high
                                                                               mineral particle content. PMT- contained carbon
                                                                               aggregates,  and polycyclic aromatic hydrocarbons
                                                                               (PAH). PMW and DEP contained carbon
                                                                               aggregates. PAH content of PMW was greater than
                                                                               DEP. Porphyr was not included in the analysis.
    
                                                                               Cytokines: PMT+ induced releases of TNF-a, IL-1|3,
                                                                               and IL-8 with 30 or 70 pg/mL PMW similarly
                                                                               induced TNF-a and IL-8. DEP induced IL-lp and IL-
                                                                               8. Porphyr induced IL-8 increases.  IL-4, IL-6 and IL-
                                                                               10 were unaffected. Overall, the order of effective
                                                                               cytokine induction from most to least effective was
                                                                               PMT+, PMW, DEP, and Porphyr.  mRNA expression
                                                                               of TNF-a, IL-1P, IL-8, and IL-10 increased with 140
                                                                               pg/mL of PMT+ and slightly for PMW
    
                                                                               LDH: PMT + induced small but statistically
                                                                               significant increases at low doses. DEP increased
                                                                               LDH at 280 pg/mL only.
    
                                                                               Polymyxin B Sulphate: The endotoxin inhibitor
                                                                               significantly inhibited  LPS-induced cytokine release
                                                                               by 80-90% and reduced PMT+ induction by 50-60%.
    
                                                                               Organic Extraction: PMT+ washed and native
                                                                               particles showed equivocal induction of cytokine
                                                                               release. PMT+  organic extract had no effect. PMT-
                                                                               and PMW organic extracts significantly increased
                                                                               TNF-a and IL-8. Washed particles induced less
                                                                               significant increases of IL-8. DEP organic  extract
                                                                               had no effect.
    December 2009
                                                   D-54
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Kristovich
    et al. (2004, 0879631
    
    Species: Human
    
    Cell Type/Line:
    HUVEC, HPAEC,
    HPMVEC, HPBMC
    CP: carbon particle (carbonaceous
    negative image of zeolite)
    
    CFE: C/Fe particulate (synthesized)
    
    CFE+: C-Fe/F-AI-Si particulate
    (synthesized)
    
    CFA: Coal Fly Ash (Coal-fired power
    plant, NOS)
    
    DEP: (exhaust pipe of diesel powered
    truck)
    
    CP, CFE, CFE+ approx 1 pm
    (resembling zeolite)
    
    Particle Characterization (Surface
    chemistry): CP = 88% C, 1% Si, 10%
    0, 1% N. CFE = 80% C, 2% Fe, 2% Si,
    16% 0. CFE+ = 20% C, 6% Al, 3% Si,
    50% F, 6%0, 11% N, 4%Na.
    CFA = 25% C, 3% Fe, 13% Al, 17% Si,
    41 %0, 1%N.  DEP = 70%C, 3%Fe,
    24% 0, 1%N, 2%S.
    
    Particle Size: CP, CFE, CFE+:
    approximately 1 pm (resembling
    zeolite); CFA: <2 pm; DEP: 150 nm
    Route: Cell Culture (4x1 Ob cells/well)
    
    Dose/Concentration: CP: 5-50 pg/cm2;
    CFE: 2.5-25 pg/cm2' CFE+: 2.5-25 pg/cm2;
    CFA: 10-100 fjg/cm ,  DEP: 2.5-25 pg/cm2
    
    Time to Analysis: 4,  8, or 24 h
    Cytotoxicity: CP exhibited no effects. DEP and
    CFE exhibited intermediate toxicities in the range of
    50-70 pg/cm2.  No toxicity was apparent when
    treated with CFA (up to 200 pg/ cm ) or synthesized
    C particulates.
    
    Endothelial Activation: ICAM-1, VCAM-1, and E-
    selectin were activated dose-dependently by DEP,
    CFE, and CFE+. No effects observed for CFA or CP.
    These effects were not the result of endotoxin
    release.
    
    Individual Variability: Donors (humans) showed
    variability in responses especially for CFA. 3/9 had a
    medium  response negated by ND responses in 6/9.
    Reference: Kubatova
    et al. (2006, 1988351
    
    Species: Rat, Human   burning hardwoods"
    PMW: Wood Smoke
    
    Collected from airtight wood stove
    Route: Cell Culture (RAW264.7:10b
    cells/ml; BEAS-2B: 105 cells/ml)
    
    Dose/Concentration: 50,100, 200 pg/mL
    Cell Type/Line: RAW   -P: Polar (fraction extracted from 25-50  Time to Analysis: 12 h
    264.7, BEAS-2B       C)
    
                         -MP: Mid Polar (fraction extracted from
                         100-150 C)
    
                         -NP: Nonpolar (fraction extracted from
                         200-300 C)
    
                         -C: P + MP + NP
    
                         Particle Size: NR
    GSH: PMW-MP and PMW-NP induced GSH
    depletion substantially in a dose dependent manner
    starting at 50 pg/mL in both cell types. DMSO had
    no effect.
    
    Cytotoxicity: PMW-MP and PMW-NP increased
    cytotoxicity at 200 pg/mL in RAW264.7. BEAS-2B
    was unaffected.
    
    Particle Characterization: PMW-MP contained
    higher concentrations of oxy-PAHs, disyringyls,
    syringylguaiacyls and PAHs. oxy-PAHs include 9-
    fluorenone, 1-phenalenone, 9,10-anthraquinoneand
    hydroxycadalene. PAHs included phenanthrene,
    fluoranthene  and pyrene.
    
    Effects of Individual Components of PMW-MP on
    GSH: 1,8-dihydroxy-9-10anthraquinone and 9,10-
    phenanthraquinone depleted GSH. 9,10-
    anthraquione, anthrone, 1-hydroxypyrene increased
    GSH. Phenanthrene, 1-methylpyrene, 9-fluorenone
    and xanthone had no effect.
    Reference: Kubatova
    et al. (2004, 0879861
    
    Species: Monkey
    
    Cell Type/Line:
    African green monkey
    kidney cells
    designated COS-1
    (CV-1 cells with origin -
    defective mutants of
    SV40), E coli PQ 37
    (SOS Chromotest)
    DEP: Obtained from diesel bus
    
    PMW: Wood smoke particulates
    obtained from airtight wood stove
    burning hardwood
    
    HSF: Hot pressure fractionation
    
    -C: P + MP + NP
    -P: Polar
    -MP: Mid  Polar
    -NP: Nonpolar
    OE: Organic Extraction
    -HNP: n-hexane nonpolar
    -MEP: methanol polar
    
    Particle Size:  NR
    Route: Cell Culture (10,000 cells/180 \i\)
    
    Dose/Concentration: 0, 50,100,150, 200,
    250, 300 pg/mL
    
    Time to Analysis: Cytotoxicity: 24 h;
    Chomotest: 2 h SOS
    Cytotoxicity: PMW induced cytotoxicity in a dose-
    dependent manner. PMW-HNP induced low
    cytotoxicity, followed by PMW-C (intermediate) and
    PMW-MEP (highest).  Levels above 25 pg/mL were
    cytotoxic. DEP-HNP induced cytotoxicity but was not
    dose-dependent. Results similar for all 3 fractions
    (highly variable). All fractions with concentrations
    higher than 100 pg/mL were cytotoxic.
    
    Extraction Water Temperature Effect: PMW was
    cytotoxic at temperatures over 50 C. DEP was
    cytotoxic at temperatures higher than 200° C. At
    250", cytotoxicity between DEP and PMW was
    similar. At 300° C, PMW cytotoxicity declined and
    DEP stayed high, resulting in DEP inducing higher
    cytotoxicity than PMW.
    
    SOS Chromotest: (3-Galactosidase formation
    increased, peaked at  200° C with DEP and declined
    to control at 300° C. Individual fractions showed
    linear dose response  from 25-200 pg/mL with 150° C
    and 200° C extracts significantly higher.
    December 2009
                                                   D-55
    

    -------
    Study Pollutant
    Reference: Lee et al. MEP: Motorcycle Exhaust Particles
    (2005, 1566821 (Yamaha Cabin engine, 95 octane
    Species: Human
    ~,,T „- ,c,n MEPE: MEP Particle Free
    Cell Type/Line: A549
    Exposure
    Route: Cell Culture (1 xio5 cells/well)
    Dose/Concentration: MEP 0.02, 0.2, 0.2, 2,
    20 |jg/mL; MEPE 20 pg/mL
    Time to Analysis: 24 h
    Effects
    IL-8: MEP induced IL-8 at concentrations greater
    than 0.2 pg/mL Levels increased 2fold at 24 h with
    pg/mL Induction of IL-8 mRNA expression was
    dose-dependent with MEP and MEPE.
                         Particle Size: MEP 0.5 pm; MEPEO.2
                         pm
                                                                              Cytotoxicity: Exposure to particles did not affect
                                                                              cytotoxicity.
    
                                                                              NF-KB: MEP (20 pg/l) induced time-dependent
                                                                              activation for 2 h and continued at same level for up
                                                                              to 6 h. Pretreatment of PDTC (1 mM) fully inhibited
                                                                              MEP induction.
    
                                                                              MAP Kinase: MEP induced time-dependent
                                                                              activation up to 30 min and stayed elevated for at
                                                                              least 60 min.
    
                                                                              ROI: MEP treatment induced a time-dependent
                                                                              increase in ROI for up to 1 h and then continued the
                                                                              at same level for up to 6 h.
    Reference: Lee and
    Kang (2002, 1988641
    
    Species: Mouse
    
    Cell Type/Line:
    Peritnoeal
    Macrophages, RAW
    264.7
    MEP Yamaha 2-stroke engine using
    unleaded gas)
    
    MEPE(particle-free MEP)
    
    Particle Size: Q.5|jm
    Route: Cell Culture (5x1 Ob cells/mL
    (Cytotoxicity), 3x105 cells/mL (Apoptosis),
    2x106 cells (MMP and ROI), 1 xio7 cells
    (GSH)
    
    Dose/Concentration: 5,10, 50,100, 300,
    1000 |jg/mL
    
    Time to Analysis: 6,12, 18, 24 h
    Cytotoxicity: Viability decreased dose and time-
    dependently in all cell types at 24 h.
    
    Apoptosis: subG1 significantly and dose-
    dependently increased at the 300 MEP pg/mL dose
    in all cell types, indicating increased apoptosis.
    MEPE induced similar results. Inhibition was
    successful against MEP-induced apoptosis by
    calcium chelators EGTA, BAPTA-AM, cyclosporin A
    and antioxidants MAC,  GSH, catalase and SOD.
    
    Ca2+: MEP and MEPE increased Ca2* at 300
         L. BAPTA-AM completely inhibited induction.
                                                                                                  ROI: MEP increased ROI in a time-dependent
                                                                                                  manner. Calcium chelators and antioxidants
                                                                                                  substantially attenuated induction.
    
                                                                                                  GSH: MEP significantly decreased GSH.
    
                                                                                                  MMP: Mitochondria membrane potential decreased
                                                                                                  dose-dependently with MEP 100 (jg/mL and 300
                                                                                                  pg/mL Calcium chelators and antioxidants partially
                                                                                                  inhibited reduction.
    Reference: Li et al.
    (2002, 0420801
    
    Species: Mouse
    VACES (Biosampler PM10 in Downey,
    CA-DEP concentrate in water)
    
    DEPM (DEP methanol extract)
    Cell Line: RAW264.7,  DEPME (DEP methylene chloride
    THP-1                extracts)
    
                         DEPAL (DEPME aliphatic (hexane))
    
                         DEPAR (DEPME aromatic
                         (hexane/methlene chloride))
    
                         DEPPO (DEPME polar (methylene
                         chloride/methanolj)
    
                         Particle Size: NR
    Route: Cell Culture (2x106 cells/well Mouse
    RAW264.7 and THP-1 ;0.67x106 cells/well
    Murine RAW 264.7)
    
    Dose/Concentration: 10-200 pg/mL
    
    JNKActivation and IL-8 Production: THP-1
    cells- 0, 10, 25, 50, 100 pg/mL DEPM; THP-
    1 cells-0,10, 25, 50,100|jg/mLof DEP;
    RAW264.7 cells-10-100 DEP pg/mL
    
    Cytotoxicity: 1,10, 25 (THP-1  cells only), 50,
    100, 200 pg/mL
    
    GHS/GSSG:0, 10, 25, 50, 100|jg/mL
    
    HO-1 Expression: 0, 25, 50,100, 200 pg/mL
    
    Time to Analysis: GHS/GSSG: DEPM,
    whole DEP (RAW264.7 only)  8 h.
    
    HO-1, MnSOD Expression: RAW264.7,
    THP-1 7h. RAW 264.7 cells exposed to
    whole DEP 16 h.
    
    JNKActivation, IL-8 Production: THP-1 cells
    30 min, 16 h. RAW264.7 cells 90 min.
    
    Cytotoxicity: RAW264.7, THP-1 18 h.
    GSH/GSSG Ratio: DEPM induced dose-dependent
    decrease in GSH/GSSG ratios in both cell lines.
    DEP induced decreases at comparable doses to
    DEPM.
    
    HO-1 Expression: Cells exhibited dose-dependent
    increases in HO-1 expression.
    
    HO-1 Expression in Murine RAW 264.7: VACES-F
    consistently induced HO-1 expression over a 9m
    period, whereas VACES-C was effective in inducing
    HO-1 during fall and winter. HO-1 induction
    positively correlated to higher OC and PAHsthat
    were represented in VACES-F, but also seen with a
    rise in PAHs in VACES-C during winter months.
    
    MnSOD: At doses of 2.5 pg/mL, DEPM increased
    MnSOD in  THP-1 cells.
    
    JNKActivation: DEPM dose-dependently
    increased JNK phosphorylation but did so without a
    change in the JNK expression level. DEP-exposed
    mouse RAW264.7 cells exhibited similar increases
    in JNK phosphorylation but without increasing JNK
    expression.
    
    IL-8: Exposure to DEPM elicited dose-dependent
    increase in IL-8 levels of THP-1 cells.
    December  2009
                                                  D-56
    

    -------
           Study
                Pollutant
                  Exposure
                      Effects
    Reference: Li et al.
    (2002, 0874511
    
    Species: Human
    
    Cell Line: BEAS-2B,
    NHBE, THP-1
    macrophages
    DEPM (DEP methanol extract)
    
    DEPME (DEP methylene chloride
    extracts)
    Route: Cell Culture (10bcells/mL)
    
    Dose/Concentration: 0,10, 25, 50,100
    pg/mL
    DEPAL (DEPME aliphatic (hexane))    Time to Analysis: 30, 60,120 min
    
    DEPAR (DEPME aromatic
    (hexane/methlene chloride))
    
    DEPPO (DEPME polar (methylene
    chloride/methanolj)
    
     Particle Size: 0.05-1 pm
    ROS: BEAS-2B cells demonstrated increased HE
    fluorescence, indicating increased ROS formation.
    THP-1 cells were unaffected.
    
    GSH/GSSG Ratio: DEPM dose-dependently
    decreased GSH/GSSG in THP-1 and BEAS-2B
    cells. Similar changes occurred with NHBE cells.
    THP-1 cells maintained a higher ratio of GSH/GSSG
    than BEAS-2B and NHBE cells.
    
    MAC on GSH/GSSG Ratio: Exposure to DEPM in
    the presence of NAC did not affect the GSH/GSSG
    ratio in BEAS-2B and NHBE cells. In THP-1 cells,
    NAC prevented a decline in the GSH/GSSG ratio.
    
    MnSOD and HO-1: THP-1,  BEAS-2B and NHBE
    cells showed constitutive MnSOD expression and
    dose-dependent expression of HO-1 protein and
    mRNA. No change occurred in the expression of |3-
    actin.
    
    DEPAL, DEPAR, DEPPO, CoPP on HO-1
    Expression: DEPPO was more potent than DEPAR.
    DEPAL lacked activity for THP-1 and BEAS-2B cells.
    The potency of DEPPO was sufficient to affect
    cellular viability and HO-1. CoPP induction of HO-1
    failed in THP-1 cells, but succeeded in BEAS-2B
    cells. However, it did not protect against the
    oxidizing effects of DEPM.
    
    JNK: JNK activation increased in DEP-exposed
    THP-1 and BEAS-2B cells. JNK isoforms were
    observed at doses of > 25 pg/mL. In BEAS-2B cells
    a high rate of cell death diminished this response at
    100 pg/mL NHBE also showed increased JNK
    phosphorylation at doses 50-100 pg/mL
    
    NAC on JNK:  NAC led to inhibition of JNK
    activation.
    
    IL-8: THP-1 cells showed dose-dependent increases
    of IL-8. NHBE cells showed incremental increases
    followed by rapid decline at 100 pg/mL attributed to
    apoptosis. BEAS-2B cells responded to 10 pg/mL
    with increased IL-8, but cellular toxicity and cell
    death led to a drop in IL-8 production at higher
    doses.
    
    Cytotoxicity: Comparing cytotoxicity at 25 pg/mL
    DEP, BEAS-2B cells had a higher rate of cell death
    than THP-1 cells. BEAS-2B cells showed a
    significant rise in cell death at doses larger than 10
    pg/mL In THP-1 cells, it took doses of 25 pg/mL or
    more before significant increases occurred.
    
    In BEAS-2B, cell death began at 2 h. In  THP-1,
    increases in cell death prolonged for 8h  or longer.
    NHBE cells also showed increase rates of
    cytotoxicity compared to macrophages. NAC in
    THP-1 interfered with a generation of cytotoxicity,
    but NAC did not have any decreasing effect on cell
    death in BEAS-2B or NHBE cells.
    December  2009
                                                  D-57
    

    -------
           Study
    Pollutant
                                                     Exposure
                       Effects
    Reference: Lindbom
    et al. (2007, 1559341
    
    Species: Mouse
    
    Cell Line/Type: RAW
    264.7
                           Route: Cell Culture (130,000 cells/cm')
    
                           Dose/Concentration: 1,10 or 100 pg/mL
    
                           Tlme to Analysis: 18, 24 h
    PM10:
    
    -ST: Street
    
    -S: Subway
    
    -G: Granite                          Analysis of Arachidonic Release (AA): Cells
                                       pre-incubated w/1 pCI tritium marked for AA
    -Q: Quartzite                        and wasned exposed to 10, 50,100 and 250
    
    (-G and -Q generated by road simulator  ^ m
    at Swedish National Road and
    Transport Research Institute)
    
    Particle Size: PM10; Bimodal with
    peaks around 4-5 urn and  7-8 urn.
    Cellular Viability: Viability was not influenced by
    any particle types and in all cases exhibited 90% or
    higher viability, except for the combination of subway
    particles and MAC where viability dropped to 20%.
    
    Cytokines: All particles induced TNF-a secretion in
    a dose-dependent fashion. PM-S was most potent at
    1 fjg/mL PM-G and PM-ST induced effects at 10
    pg/mL PM-Q induced increase of TNF-a at 100
    |jg/mLPM-ST induced IL-6 release at 10 pg/mL.
    PM-G, PM-Q, PM-S induced IL-6 secretion at 100
    pg/mL DFX inhibited TNF-a in cells exposed to PM-
    S and PM-ST. DFX induced increase of TNF-a with
    PM-Q. For all PM types (except PM-ST) DFX
    inhibited induced IL-6 secretion.
    
    NO: PM-ST and PM-G induced a significant release
    of NO, with PM-ST inducing a higher NO release
    than PM-G.
    
    MAC: NAC treatment significantly inhibited both
    TNF-a and IL-6 secretion with all PM particles.
    
    L-NAME: L-NAME caused a decrease in NO
    secretion at 100 pg/mL of  PM-ST. L-NAME did not
    have an effect on granite-induced NO secretion at
    100 pg/mL
    
    Cytokine Gene Expression: TNF-a mRNA showed
    a trend to increase for -ST, but this did not reach
    significance. IL-6 gene expression increased for PM-
    Q, PM-ST, PM-S but not for PM-Q.
    
    AA Release: PM-S exposure at 100 and 250 pg/mL
    was the only PM to induce AA release.
    
    Lipid Peroxidation: All particle types induced lipid
    peroxidation. PM-S and PM-ST induced significantly
    higher lipid peroxidation as compared to PM-Q and
    PM-G.
    
    ROS: All particle types induced ROS formation. PM-
    S and PM-ST induced significantly higher formation
    at 10 pg/mL PM-Q and PM-G induced small but
    significant decreases in absorption at 100|jg/mL.
    Both PM-ST and PM-S had significant dose
    responses for all concentrations tested. No
    difference was observed between PM-G and PM-Q.
    PM-S and PM-ST pretreated with DFX had a lower
    ability to induce ROS formation.
    
    Endotoxin Content: Only PM-ST showed  positive
    results for endotoxin content.
    December  2009
                                       D-58
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Liu et al.
    (2005, 0883041
    
    Species: Human
    
    Cell Type: HPAECs
    SE: V\food Smoke Extract; generated
    using a stainless steel receptacle
    containing 100g of dry wood dust
    
    Particle Size: NA
    Route: Cell Culture
    
    Dose/Concentration: 40 |jg/mL
    
    Time to Analysis: 0-4 h; Mitochondria!
    Membrane Destabilization: 0-60 min; DMA
    Defragmentation: 0-6 h; Cytotoxicity: 24 h
    Viability: SE exposure reduced cell viability dose-
    dependently Reduction reached ~38% of control.
    
    Effect on Oxidative Stress/Antioxidant Enzymes:
    SE caused an increase in ROS levels, in particular
    02- and H202 in a time-dependent manner.
    Exposure to SE for up to 4 h caused a decrease in
    GSH levels in a time-dependent manner. Increased
    expression of Cu/Zn SOD mRNAand HO-1 mRNA
    was observed. Catalase or GPx mRNA expression
    was unaffected. Upregulation of Cu/Zn SOD and
    HO-1 occurred in a time-dependent manner
    
    Mitochondrial Translocation/ Capsase-
    Independent Apoptosis/DNA fragmentation:
    Exposure for up to 60 min caused an increase in the
    percentage of annexin V-FITC-pos cells but not Pl-
    pos cells. At 4 h, FDA-pos cells was unaffected. SE
    exposure caused a loss of mitochondrial membrane
    potential (indicated by the change in JC-1
    fluorescence). Cytosolic bax levels  increased  after
    exposure for 1 or 2 h and returned to basal level at
    4 h after exposure. Levels of procaspase-3 and
    caspase-9 were unaltered by SE exposure after 4 h.
    Procaspase-3 increased and caspase-9 decreased
    by H202 exposure. SE exposure increased levels of
    AIF and EndoG (exposure up to 4 h). At 6 h,
    increased DNAdefragmentation was observed. Pre-
    treatment with caspase inhibitors (CMK  and Z-VAD-
    FMK) failed to suppress SE-induced apoptosis.
    
    MAC: Treatment with MAC prevented ROS increase
    in cells exposed to SE for 60 min. MAC addition
    prevented the reduction of GSH by SE.  MAC
    decreased nuclear levels of AIF and EndoG and
    completely reduced  DNA-fragmentation. MAC
    alleviated the SE-induced reduced viability. GSH
    and DMA fragmentation were unaffected by MAC.
    Reference: Long et al.
    (2005, 0874541
    
    Species: Human
    
    Cell Types: Human,
    Peripheral blood
    mononuclear cells
    (PBMCs) differentiated
    into MDMs (90-95 %
    CD14+)andT
    lymphocytes
    Synthetic C and C/Fe particles (phenol
    and paraformaldehyde polymers on a
    zeolite template)
    C/Fe analysis Al 1.38 %, Si 0.33 %, Fe
    0.46%
    
    Particle Size: 1 |jm
    Route: Cell Culture (5x106 cells, 2 mL /well
    MDMs) Dose/Concentration: 5 pg/cm
    
    Time to Analysis: 2-24 h
    ROS release: Oxidative burst form C/Fe maxes out
    at 20 min with no effect from C particles.
    
    Cellular participate actions: C particulates were
    present within lysosomes with small clumps forming
    after 24 h outside of lysosomes with no evidence of
    organelle lysis and/or agglomeration. C/Fe
    particulates showed similar initial effects progressing
    at 24-h total organelle  lysis extending to the outer
    cell membrane.
    
    T cell effects: No effects from C or C/Fe particles
    Medium  Effect: Particle agglomeration appears to be
    a direct result of serum present within a cell free
    medium
    
    Hydroxyl radical formation: C/Fe particles showed
    an order of magnitude of higher hydroxyl formation
    as compared to C particles
    December 2009
                                                   D-59
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Ma et al.
    (2004, 0884171
    
    Species: Mouse
    
    Cell Line: JB6P+
    (Epidermal Cell Line)
    DEP: SRM 1975
    
    Particle Size: 0.5pm
    Route: Cell Culture
    
    Dose/Concentration: Non-cytotoxic: 5,10,
    20 pg/mL; Cytotoxic: 0,10, 20, 40, 80,100,
    160 pg/mL
    
    Tlme to Analysis: 24, 48 h;
    
    NF-KBandAP-1:12h
    
    Phosphorylation of Akt: 5-120 min.
    
    Effect of LY294002 on DEP: Cells pretreated
    with LY294002 (0 or 10 pM) for 30 min and
    then exposed to DEP for 0-60 min.
    Viability: Below 20 pg/mL, DEP had no effect. At
    concentrations greater than 20 pg/mL, DEP caused
    apoptosis.
    
    NF-KB and AP-1: DEP stimulated NF-KB activity at
    5 and 10 pg/mL. At 20 pg/mL, NF-KB activity
    decreased, but was still greater than the control.
    DEP had no effect on AP-1 activity.
    
    PI3K/Akt Signaling Pathway: DEP induced
    phosphorylation of Akt on both Thr-308 and Ser-473.
    LY294002 (an inhibitor of P13K) blocked
    phosphorylation of Akt, p70/p85 s6 kinase and GSK
    3b. LY294002 eliminated DEP-mediated
    phosphorylation of Akt. Inhibition of P13K by
    expressing p85 also blocked DEP-induced Akt
    phosphorylation. DEP induced phosphorylation on
    GSH-3B on Ser-9 without affecting tyrosine
    phosphorylation and enhanced phosphorylation of
    p70/p85 S6 kinase on Thr-389. DEP had no effect
    on phosphorylation of FKHR.
    
    SAPK/JNK Pathway: DEP slightly activated the
    pathway. Increased transient activation of MKK4 (a
    signal component of the SAPK/JNK pathway) and
    thus enhanced phosphorylation of SAPK/JNK. DEP
    promoted phosphorylation of c-Jun and ATF-2.  DEP
    did not affect p38 MAPK or ERK phosphorylation.
    
    LY294002: Treatment with LY294002  (P13K
    inhibitor) eliminated DEP-induced NF-KB activity. A
    similar effect was observed with the use of another
    P13K inhibitor, wortmannin. TDZD-8 (GSK-3B
    inhibitor), D-JNKI(a JNK inhibitor), SB202190
    (inhibitor for p38 MAPK) or PD98059 (inhibitor for
    MEK1) had little effect on DEP-mediated NF-KB
    activation.
    Reference:
    Maciejczyk and Chen
    (2005, 0874561
    
    Species: Human
    
    Cell Type: BEAS-2B
    CAPs: PM25
    
    Collected via cyclone inlet on side of
    building in Tuxedo, NY. Weekdays 9-3
    March 4 to September 5, 2003
    
    Mass contributions of the Regional
    Sulfate, Soil,  Oil- Combustions and
    Unknown/other categories to CAPs are:
    Regional Sulfate- 65%, Soil- 20%,
    Unknown/Other-13% and Oil
    Combustion- 2%.
    
    Composition:
    
    * Regional Sulfate characterized by
    high concentrations of S, Si and .
    
    * Soil characterized by high
    concentrations of Ca, Fe, Al  and Si.
    
    * Oil-Combustion characterized by high
    concentrations of V, Ni and Se.
    
    Particle Size: PM25
    Route: Cell Exposure (subchronic
    exposures); Cell Culture (NF-KB) (9x104
    cells/well)
    
    Dose/Concentration: CAPS 109 + 178
    pg/m3 (air exposure); 300 pg PM/ml (culture)
    
    Time to Analysis: 24 h
    NF-KB: NF-KB response most notably correlated
    with V and Ni - elements associated with oil
    combustion source category (oil combustion makes
    up the group that is the smallest percentage of CAP
    mass).
    December 2009
                                                   D-60
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Madden et
    al. (2003, 1988771
    
    Species: Human
    
    Cell Type: NHBE
    DEP(SRM 2975)
                                                            Route: Cell Culture
                         Obtained from Caterpillar diesel engine,
                         4 cycl, 4 stroke, model 3304
    Diesel Exhaust Extracts from a High    Dose/Concentration: 0,10, 50,100, 250,
    load (HL~75% engine load) or Low load 500 pg/well
    (LLO% engine load):                       t  .  ,   -   „, t,  „  -i.  ,
                                       Time to Analysis: 24 h (after 2 h of
                                       treatment, 0.5 ml of BEGM added to each
                                       well and cells incubated for an additional 22
    
    Particle Characterization: LL extract
    has greater amount of low-molecular-
    weight carbonyls (2-5 carbons).  HL had
    more intermediate size carbonyls (6-9
    carbons). Largest carbonyls analyzed
    (11-12 carbons) found in similar ratios
    in the two types of extract (number of
    carbons is indicative of differences in
    boiling points).
    
    Particle Size: NR
                                            Cytotoxicity: LL, HL and SRM had no effect on
                                            LDH release.
    
                                            61Cr: Incubation of cells with LLorSRM (10 to 500
                                            pg/well) had no effect. 500 pg/well of HL induced a
                                            significant increase in 51 Cr release.
    
                                            IL-8: HL induced a 5-fold  increase in  IL-8 at 500
                                            pg/well. A decrease was observed at  the highest
                                            dose of LL extract. SRM did not significantly alter IL-
                                            8 production.
    
                                            PGE2: Production of PGE2 (inflammatory/immune
                                            mediator) increased in cells treated with HL extract
                                            at 500 pg/well. LL had no effect. Stimulation with
                                            melittin caused LL extract to have inhibitory effect on
                                            PGE2 at 500 pg/well. SRM had no effect.
    Reference: Matsuo et
    al. (2003, 1988791
    
    Species: Human
    
    Cell Type: NHBE,
    NHPAE, TIG-1.TIG-7
    (normal human lung
    embryonic fibroblasts)
    DEP: prepared at National Institute for
    Environmental Studies (Tsukuba,
    Japan)
    
    RDEP: residual DEP (after sequential
    extraction with hexane (NOS),
    benzene, dichloromethane, methanol,
    1N ammonium hydroxide)
    
    Particle Size: 0.4 pm(MMAD)
    Route: Cell Culture (NHBE: 5x104 cells/cm ,
    NHPAE: 3x103 cells/cm2; TIG-1 and TIG -7:
    3x103 cells/cm2. Apoptosis: 2x105 cells/cm2;
    ROS/NO: 2x10 cells/cm2; Cytotoxicity
    Modulating Agent: 3x104 cells/cm2; GSH:
    3x104 cells/cm2)
    
    Dose/Concentration: 25, 50,100, 200, 300,
    400, 500 pg/mL
    
    Time to Analysis: 1 h
    Cytotoxicity in NHBE: Both DEP and RDEP
    exhibited dose-dependent Cytotoxicity at
    concentrations beginning from 50 pg/mL and higher.
    RDEP was less cytotoxic than DEP. DEP exposure
    resulted in necrosis, not apoptosis.
    
    Comparative Cytotoxicity: The order of LC50
    values (50%  lethal concentration) was:  NHBE (118
    fjg/ml),  NHPAE (137 pg/ml), TIG (270 fjg/ml).
    NHBE's susceptibility was higher than the
    susceptibility of NHPAE and TIG cells.
    
    ROS/NO: DEP induced dose-dependent increases
    at25and50|jg/mL
    
    Reduced Glutathione: DEP induced dose-
    dependent decreases. At 200 or 300 pg/mL, GSH
    levels decreased by 55.2 or 97.3%, respectively.
    
    Antioxidant  Effects: Various antioxidants either
    decreased DEP Cytotoxicity (PMC, Ebselen, EUK-8)
    or had no effect on DEP Cytotoxicity (SOD, catalase,
    GSH, a-tocopherol)
    
    Chelating Agents: DEP became less cytotoxic
    when lon-chelating agents were preincubated for
    24 h. No effect on DEP Cytotoxicity was observed
    when chelating agents were administered to cells
    immediately after sonication.
    
    Endocytosis inhibitors: Decreased DEP toxicity
    was observed in a dose-dependent manner.
    Reference: Matsuzaki
    et al. (2006, 1995171
    
    Species: Human
    
    Cell Type: Peripheral
    neutrophils
    
    Gender: Male and
    Female
    
    Age: 20-40 yrs
    DEP: generated from a 4JB1-type, 4
    cyl Isuzu diesel engine
    
    me-DEP: methanol extract of DEP (40
    % of DEP by dry weight)
    
    Particle Size: 04 |jm
    Route: Cell Suspensions (5x10 cells/mL)
    
    Dose/Concentration: all me-DEP
    
    f-actin: 1, 5,10|jg/mL
    
    CD11b:5,10, 30|jg/mL
    
    IL-8: 5,10, 30|jg/mL
    
    H202:5,10, 30, 60|jg/mL
    
    MMP-9, LTB-4:5, 10, 30, 60|jg/mL
    
    Time to Analysis: f-Actin: 15 min
    
    CD11b:2h
    
    IL-8:2or24h
    
    H202:  30 min
    
    MMP-9, LTB-4:2or24h
    F-Actin: Treatment with me-DEP showed a dose-
    dependent increase in the f-actin content of
    neutrophils and this  increase was significantly higher
    at 5 and 10|jg/mL
    
    CD-11b: Treatment increased CD-11b expression
    two-fold at 30 pg/mL
    
    IL-8: Minimal response was observed after 2 h. A
    significant increase was observed (243%) at 24 h
    with 30 fjg/mL.
    
    LTB-4: At 2  h, LTB4 increased to 115% and 119%
    with 30 and  60 pg/mL me-DEP respectively. At 24 h
    with 60 |jg/mL me-DEP,  LTB-4 increased to153%.
    
    H&f. Exposure to 30 and 60 pg/mL of me-DEP
    induced large dose-dependent increases of 563%
    and 1220%, respectively.
    
    MMP-9: A significant increase at 2 and 24 h were
    observed. In both exposure periods, 30 pg/mL
    induced larger increases than 60 pg/mL
    December 2009
                                                   D-61
    

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           Study
                                      Pollutant
                  Exposure
                       Effects
    Reference: Molinelli et  PMH: PMi0 extracts in hexane
    al. (2006, 198949)      nllA   nll    t   t .
             	       PMA = PM10 extracts in acetone of
                          residue after hexane extraction
    Species: Human
    
    Cell Type: NHBE,
    BEAS-2B
                                                              Route: Cell Culture (3x10' cells/well)
    
                                                              Dose/Concentration: NHBE exposed to 0-
                          -G: Guaynabo(Urban) and
    
                          -F: Fajardo (Preservation Area)
    
                          Particle Size: PM10
    BEAS-2B exposed to 10,100, 250 pg/mL of
    PM10
    
    Time to Analysis: 48 h
    Metal analysis: Hexane extracts Cu, V, Ni all higher
    in winter than summer. For hexane extracts within
    the same season, metal concentrations were higher
    in the Fajardo extracts. On the other hand, the
    acetone extracts from Guaynabo generally had
    higher metal concentrations than Fajardo.
    
    Cytotoxicity NHBE: The order of most to least toxic
    for PM extracted with hexane is: winter-G, winter-F,
    summer -G , summer-F The order of most to least
    toxic for PM extracted with acetone is: summer-G,
    summer-F, winter-g.
    
    Cytotoxicity BEAS-2: For PM extracted with
    hexane, the Cytotoxicity order is: winter-G, winter-F,
    summer-G, summer-F. The order for acetone
    extracted PM is: summer-G , summer-F, winter-F,
    winter-G.  Effects trend similar to metal levels (no
    analysis). Summer extracts showed linear dose-
    response curves. Winter extracts exhibited more
    equivocal results, especially for Fajardo. Results
    suggest that NHBE cells are more sensitive than the
    BEAS-2B cells to PM extracts.
    Reference: Holler et
    al. (2002, 0365891
    
    Species: Canine,
    Mouse
                          fTi02 (origin NR)
    
                          ufTi02 (origin NR)
                          ufP-G: carbon black (Printex-G,
                          Degussa, Frankfurt, Germany)
    Cell Type: Beagle-Dog
    Alveolar Macrophages   ufP90: carbon black (Printex90,
    —	— •       Degussa, Frankfurt, Germany)
    Route: Cell Suspension
    
    Dose/Concentration: 10, 32,100, 320
    pg/mL
    
    Time to Analysis: 24 h
    (BD-AM), J774A.1
                          ufEC90: EC (produced by electrical
                          spark generator under standardized
                          conditions with low impurities)
    
                          DEP(SRM1650)
    
                          UrbD: Urban Dust (SRM 1649a)
    
                          Particle Size: (in diameter) Ti02: 220
                          nm; ufTi02: 20 nm; ufP-G: 51 nm;
                          ufP90:12 nm; ufEC90: 90 nm;
                          DEP: 120 nm; UrbD: NR
    Cytoskeleton of J774A.1: At doses of 32 pg/mL or
    less, the particles did not significantly influence
    relaxation and stiffness. fTi02and ufP90 had no
    effect at any dose. ufTi02 at 320 pg/mL induced
    retarded relaxation and significant stiffening. uEC90
    induced dose-dependent retardation of relaxation
    and increased stiffening. DEP and UrbD induced
    similar results.
    
    Cytoskeleton of BD-AM: ufTi02 and fTi02 both
    induced some retarded relaxation and increased
    stiffening at 100 pg/mL dose. ufTi02 appears to
    increase stiffening in a dose-dependent manner.
    ufEC90 induced dose-dependent acceleration of
    relaxation due to the carbon content of uEC90. DEP
    also induced acceleration of relaxation as well as a
    decrease in stiffness.
    
    Phagocytosis: At 24 h, ufTi02 and fTi02
    significantly reduced phagocytic ability in J774A.1
    but not in BD-AM. All carbonaceous particles
    induced significant impairment in J774A.1. All
    ultrafine carbon particles inhibited BD-AMs.
    
    Cell Proliferation: ufTi02 significantly inhibited
    proliferation compared to the control and fTi02 at
    100 pg/mL in J774A.1. ufEC90 and ufP90 inhibited
    proliferation slightly with uEC90 inducing slightly
    greater inhibition than  ufP90. UrbD and DEP also
    significantly reduced proliferating.
    
    Apoptosis: All particles induced decreased viability
    at 100  |jg/mL in both cell types. With ufTi02 inducing
    greater apoptosis than fTi02, uEC90 than ufP90
    and ufEC90 than ufP-G
    Reference: Mutlu et
    al. (2006, 1559941
    
    Species: Human, Rat
    
    Cell Type: A549
                          PM10
    
                          (Collected by baghouse from ambient
                          air in Dusseldorf, Germany)
    
                          Particle Size: PM10
    Route: Cell Culture
    
    Dose/Concentration: 0.05, 0.5, 5. 50
    pg/cm2
    
    Time to Analysis: 24 h
    Na, K-ATPase Plasma Membrane Protein: PM10
    induced a decrease of protein in the plasma
    membrane of A549 cells. Total Na,K-ATPase levels
    were unaffected.
    
    ROS: Pretreatment with EUK-134, superoxide
    dismutase and catalase mimetic, inhibited the
    decrease of GSH.  Furthermore, it attenuated the
    decrease of NA,K-ATPase in A549 cells.
    
    NA, K-ATPase Activity: PMi0 induced a dose-
    dependent decrease in ouabain-sensitive liberation
    of32Pfrom AT32P in primary rat alveolar type II
    cells. This effect was inhibited with pretreatment with
    EUK-134.
    December 2009
                                                                          D-62
    

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           Study
                Pollutant
                  Exposure
                                                             Effects
    Reference: Nam et al.
    (2004, 1988871
    
    Species: Human
    
    Cell Type:  A549
    PM25
    
    Collected from hospital rooftop, Seoul,
    South Korea
    
    Particle Size: PM25
    Route: Cell Culture
    
    Dose/Concentration: 0.5,1,10, 25, 50
    pg/cm2
    
    Time to Analysis: 6, 24 h
                                           NF-KB/kBa: 50 pg/cm DEP induced iKBa
                                           degradation which peaked at 2 h and recovered
                                           after 4 h. Treatment with increasing amount of PM2 5
                                           resulted in a dose-dependent decrease in IKBa.
                                           PM25 increased NF-KB in a dose-dependent manner
                                           up to 10 pg/cm2. NF-KB induction peaked at 12 h.
    
                                           IL-8: PM25 treatment increased protein level more
                                           than 3 fold with 100 pg/cm2 PM25. mRNA levels also
                                           increased.
    
                                           iNOS Inhibitor: PM25 induced IL-8 elevation was
                                           completely blocked by iNOS inhibitor. iNOS inhibitor
                                           also negated PM25 induction of NF-KB activity.
                                           Antioxidants and iNOS inhibitor reduced PM-induced
                                           IKBa degradation.
    Reference: Nozaki et
    al. (2007, 0978621
    
    Species: Mouse
    
    Cell Line: LA-4
    (Alveolar Epithelial
    Cells)
    PM: Rooftop of 5 story building, urban,
    Japan
    
    PME: dichloromethane extract of PM
    filtered
    
    P90: Printex 90 (carbon  black)
    (Degussa)
    
    Particle Size: PM: 0.22pm; PME: 2.5
    pm; P90:14 nm
    Route: Cell Culture (1.4x104 cells/cm2)
    
    Dose/Concentration: 1.1 pg/cm2
    
    Time to Analysis: 24, 28, 72 h
                                           Cytotoxicity: P90 had no effect. PM and PME were
                                           cytotoxic at similar levels.
    
                                           Protein Expression: All particles affected protein
                                           expression (no specific protein- 2D gel
                                           electrophoresis).
    Reference: Obot et al.
    (2002, 0423701
    
    Species: Mouse
    
    Cell Line: BALB/c
    
    Cell Type: AM
    PM:SRM1648
    
    PM-100:PM heated to 100° C
    
    PM-500:PM heated to 500° C
    
    PM-PH: PM acid digestion
    
    PMAC: Acetone extraction
    
    PMCH: Cyclohexane extraction
    
    PMH20: Water extraction
    
    All extract fraction used as residual
    particles
    
    Particle Size: NR
    Route: Cell Culture (5x105 cells/mL)
    
    Dose/Concentration: PM: 200 pg/mL; PM-
    100:188 pg/mL; PM-500:130 mg/l; PM-
    PH: 94 pg/mL; PMAC: 173 pg/mL;
    PMCH: 171 pg/mL; PMH20:188 pg/mL
    
    Fraction doses adjusted for mass loss during
    fraction treatment
    
    Time to Analysis: 4 h
                                           Cytotoxicity: All 7 fractions had cytotoxic effects.
                                           PM had highest Cytotoxicity. PM-500, PM-PH, PMAC
                                           less toxic than PM.
    
                                           Apoptosis: All 7 fractions significantly increased
                                           apoptosis. The PM fractions that induced the
                                           greatest apoptosis in descending order are: PM,
                                           PMH20,  PM-100, PM-500, PMAC, PMCH and PM-
                                           PH. PM-induced apoptosis (only PM, PM-500 and
                                           PMAC tested) was blocked by poly I or 2F8 antibody
                                           (scavenger receptors).
    
                                           Particle Characterization: Untreated PM and PM-
                                           100 did not have measurable amounts of transition
                                           metals on its surface. Measured components include
                                           carbon, 02, N, S, Si, Ca, Al,  P, Cl.  PM-PH mostly
                                           contained 02 and Si. PM-500 had  increased 02, Si
                                           compared to PM and measurable  amounts of Na, K,
                                           Zn, Co, Pb, Fe.  Included increased surface  density
                                           of S, P, Al. PMCH lacked nonpolar organic
                                           compounds.
    Reference: Obot et al.
    (2004, 0959381
    
    Species: Mouse (7-
    9wk), Human
    
    Cell Line: Mouse-
    BALB/c
    
    Cell Type: AM
    PM: SRM 1648 (collected by bag-
    house in St. Louis, MO).
    
    PM-100: PM heated to 100° C
    
    PM-500: PM heated to 500'C
    
    PM-PH: PM acid digestion
    
    PMAC: Acetone extraction
    
    PMCH: Cyclohexane extraction
    
    PMH20:V\Mer extraction
    
    All of the 6 extract fractions from
    PM1648
    
    PM25: Collected in Houston, TX
    
    Particle Size: PM1648: NR; PM25
    Route: Cell Culture (5x105 cells/mL)
    
    Dose/Concentration: PM: 200 pg/mL; PM-
    100: 188 pg/mL; PM-500:130 mg/l; PM-
    PH: 94 pg/mL; PMAC: 173 pg/mL;
    PMCH: 171 pg/mL; PMH20:188 pg/mL
                                           Human AM Viability: Only PM, PM-100, PMAC and
                                           PMH20 decreased viability.
    
                                           Human AM Apoptosis: PM, PM-100 and PMH20
                                           increased apoptosis. PM induced greater apoptosis
                                           than PM-100 and PMH20.
    Fraction doses adjusted for mass loss during  Regression Analysis Mouse vs Human: Although
                                           individual fractions differed somewhat, cell viability
                                           and apoptosis of all 7 fractions showed linear
                                           regression
    fraction treatment
    
    PM25 = 50, 100, 150, 200pg/mL
    
    Time to Analysis: Mouse-4 h; Human-24 h.
                                                                                                  Human and Mouse AM Viability with PM2.6:
                                                                                                  Nearly identical dose-dependent decrease was
                                                                                                  exhibited starting at 50 pg/mL
    
                                                                                                  Human and Mouse AM Apoptosis with PM25:
                                                                                                  Nearly identical dose-dependent increases were
                                                                                                  exhibited with human AM responses peaking at 150
                                                                                                  pg Art and declining at 200 pg/mL (no mouse data
                                                                                                  for200pg/mL).
    
                                                                                                  Regression Analysis with PM2.6: Excellent
                                                                                                  correlation of mouse and human responses for
                                                                                                  viability and apoptosis was exhibited.
    December  2009
                                                  D-63
    

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           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Okeson et  CG: Coal ash, Germany
    al. (2003, 0422921
    Species: Rat
    
    Cell Type: RLE-6TN
    (Type 11 Alveolar
    Epithelial Cells)
    CU: Coal ash, USA
    
    5C:PM# 5 Oil fly ash coarse
    
    5F:PM#50ilflyashfme
    
    6MSC: PM #6 Oil med sulfur fly ash
    coarse
    
    6HSC:PM# 6 Oil high sulfur fly ash
    coarse
    
    6HSF:PM# 6 Oil high sulfur fly ash
    fine
    
    Particle Size: CG, CU: NR; 5C, 6MSC,
    6HSC: >2.5 pm; 5F,  6HSF: <2.5 pm
    Route: Cell Culture
    
    Dose/Concentration: Coal Fly Ash 12.5,
    25, 50, 125, 250 pg/mL
    
    OilFlyAsh-100|jg/mL
    
    Time to Analysis: 24 h
    Oil PM Characterization: Generally, the fine
    fractions had higher metal levels than the coarse
    fractions except forZn. High sulfur had a higher
    metal content than med sulfur. Carbon percent
    weight was stable across all 5 fractions.
    
    Coal Ash Cytotoxicity: CG treatment exhibited
    similar cytotoxic results as CU. Cytotoxic effects
    were exhibited at concentrations of 12.5 pg/mL and
    above.  Effects remained  steady at concentrations
    above 50 pg/mL
    
    Oil Ash Cytotoxicity: Cytotoxic effects were
    induced by all. The order of PM fractions inducing
    the most Cytotoxicity to the least is the following: 5F,
    6HSF, 6HSC, 5C, 6MSC.
    
    Correlation of Metal Content and Cytotoxicity:
    Fe, V showed a reasonable correlation. Zn had no
    correlation.
    
    Cell Metabolism: An inhibitory effect was observed
    with 100 |jg/mL coal ash  after 6 h. After 12 h of
    exposure, CU, unlike CG, does not continue to
    inhibit cell metabolism. Oil ash was generally less
    effective than coal ash. The order of PM fractions
    inhibiting metabolism the most to the least is the
    following: 5F, 6HSC, 5C,  6MSC. 6HSF not tested.
    Reference: Okeson et  Zn, V, Fe chloride as salts (valence
    al. (2004, 0879611     state not reported)
    Species: Rat
    
    Cell Type: RLE-6TN
    (Type 11 Alveolar
    Epithelial Cells)
                         Particle Size: NR
                                        Route: Cell Culture (50000 cells/well)
    
                                        Dose/Concentration: 0.001, 0.01, 0.1,1.0,
                                        10 mM
    
                                        Time to Analysis: 24 h
                                            Cytotoxicity: All metals cytotoxic at concentrations
                                            greater than 0.1 mM. V is 5 times less cytotoxic than
                                            Zn, and Fe is 7 times less cytotoxic than Zn with a
                                            EC50 of 3mM and 4mM,  respectively. At 10 mM  of
                                            each metal, no surviving  cells were present.
    
                                            NCS: Incubation with NCS (5 or 10 %) decreased
                                            toxicity of Zn, especially at 0.1 mM, but had no effect
                                            on Fe or V toxicity.
    
                                            Albumin: BSA decreased Zn toxicity at equivalent
                                            concentrations but to a lesser extent than NCS.
    Reference: Osornio-
    Vargas et al. (2003,
    0524171
    Species: Mouse
    
    Cell Line/Type:
    J774A.1, L929
    (Mesenchymal Cells)
    PM10
    
    PM25
    
    -N = Northern (industrial)
    
    -SE = Southeastern (lake basin dust)
    sites, both heavy vehicular traffic,
    Mexico City, Mexico
    
    Particle Size: PM10;PM2 5
    Route: Cell Culture (J774A.1:15000
    cells/cm2; L929: 30,000 cells/well)
    
    Dose/Concentration: 20, 40, 80 pg/cm2
    
    Time to Analysis: 24-72 h
    PM Characterization: Elements similar in particle
    types with elements in PM10 more abundant.
    Northern particles contained more Co, Zn, Ni, Pb.
    
    Endotoxin: All PM samples had detectable amounts
    of endotoxin. PM25 -N had 22 EU/mg. PM,0-N had
    30 EU/mg. PM25 -SE had 12 EU/mg. PM,0-SE had
    59 EU/mg.
    
    Cytotoxicity (J774A.1): The two northern samples,
    PM25 and PMio, both induced similar cytotoxic
    effects at 40% survival. PM10-SE and PM25 -SE
    induced dose-dependent responses. In general, the
    northern samples had a higher cytotoxic effect than
    the southern samples.
    
    Apoptosis (J774A.1): Northern samples induced
    more apoptosis than did the southeastern samples.
    There was no difference between PM10 and PM25
    induced apoptosis.
    
    TNF-a and IL-6 (J774A.1): TNF-a and IL-6 induced
    dose-dependent increases. At 80 pg/cm2, PM10 -SE
    induced the most production of IL-6 followed by
    PM25 -SE, PM,o-N ,  and PM25 -N.
    
    J774A.1 Supernatant Toxicity (L929): Conditioned
    medium from J774A.1 pre-exposed to each PM type
    reduced cell viability in L929 cells. This was
    correlated with TNF-a level in supernatants.
    December 2009
                                                   D-64
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Penn et al.
    (2005, 0882571
    
    Species: Human
    
    Cell Type: BEAS-2B
    BDS: Butadiene soot (created on-site
    by passing BD through a back-flash
    protected stainless steel two-stage
    regulator to a stainless steel Bunsen
    burner)
    
    -P1:<2.5|jm
    
    -P2: 2.5-1 Opm
    
    -P3:>10pm
    
    BDS-W: solvent washed
    
    Graphite
    
    Composition: <2.5 pm = 92%, 2.5-10
    pm = 5%, >10pm = 3%
    
    Particle Size: BDS-P1: <2.5 pm; BDS-
    P2: 2.5-10 pm;  BDS-P3: >10 pm
    Route: Cell Culture (1-1.5x1 Ob cells)
    
    Dose/Concentration: 3 mg BDS
    
    Time to Analysis: 5 min-72 h
    Particle Characterization: By weight, EC makes up
    94% of BDS, hydrogen 2%, nitrogen and sulfur 1%,
    and oxygen less than 0.1%.
    
    PAH Components of BDS: 13 prominent PAHs:
    acenaphthylene, fluorene, anthracene,
    cyclopentaphenanthrene, fluoranthene,
    acephenanthrylene, pyrene, benzofluorenes,
    acepyrene, chrysene,  benzopyrenes, perylene,
    benzoperyiene.
    
    BDS Activity: At 60-120 min, BDS was observed in
    the cells. At 4 h,  fluorescence observed in
    cytoplasmic vesicles and increased during the first
    24 h then plateaued for the next 72 h. BDS-W
    appeared in vesicles sooner than BDS.
    Reference: Pozzi et
    al. (2005, 0886101
    
    Species: Mouse
    
    Cell Type: RAW 264.7
    PM: Collected continuously for 15 days,
    8-10 m from street, Sept 1999, Rome,
    Italy
    
    -F = Fine particulate
    
    -C = Coarse particulate
    
    CB (Degussa Huber NG90)
    
    Particle Size: PM-F: 0.4-2.5 pm; PM-
    C: 2.5-10 pm;CB: 200-250 nm
    Route: Cell Culture (1.3x105 cells/well)
    
    Dose/Concentration: 30 pg/mL; 14 pg/cm2
    
    120pg/mL;54pg/cm2
    
    Time to Analysis: 5, 24 h
    Cytotoxicity: For 24 h, lower levels of PM-F, PM-C,
    and CB had no effect on cell viability.  Higher levels
    of PM-C and CB induced a significant release of
    LDH.
    
    Arachidonic Acid (AA): Both fractions of PM
    increased AA release in a dose-dependent manner
    at 5 h. CB increased a release only at the higher
    concentrations although, in terms of magnitude, the
    CB-induced release was much less than the ambient
    PM-induced release. Pretreatment with
    deferoxamine was not effective in decreasing AA
    release.
    
    TNF-a: TNF-a levels increased significantly for both
    concentrations and time periods for PM. PM-C at
    24 h was significantly lower than at 5  h for both
    concentrations. PM-C at 30 pg/mL induced a much
    greater TNF-a release than PM-F at 5 h.
    
    IL-6: PM-F significantly increased at 5 h for both
    concentrations. Elevated IL-6 levels were exhibited
    at both PM-C doses at 24 h. At 5 h, only the high
    dose elevated IL-6 levels. CB was devoid of an
    effect on IL-6. LPS-induced IL-6 response was
    similar to coarse PM at the high dose, with the
    response being greater at 24 h than at 5 h.
    Reference: Prophete
    et al. (2006, 1568881
    
    Species: Rat
    
    Cell Type: NR8383
    AMs
    Ambient PM25
    
    NYC: 1 stand26St, NYC
    
    LA: San Gabriel foothills, Claremont,
    CA
    
    SEA: 15th Ave S and S. Charleston,
    Seattle, WA
    
    V,  Mn.AI, Fe levels in PM
    
    added metals to cells
    
    V:  Na3V04
    
    AI:AICI3-6H20
    
    Mn: MnCI2-4 h20
    
    Fe: FeCI3-6H20
    
    Particle Size: PM25
    Route: Cell Culture (2x105 cells/ml)
    
    Dose/Concentration: Fe(lll) 16 pmol
    
    V, Mn, and Fe(lll) mixtures with V or Mn in
    molar ratios 0.02, 0.08, 0.2 and 0.4 x Fe(lll)
    
    Al and Fe(lll) mixtures with Al in molar ratios
    0.37, 0.75, 2,7.5 xFe(lll)
    
    Time to Analysis: 20 h
    Particle Characterization: Fe and metal to F ratios
    based on ratios observed in PM2 5 from LA, SEA and
    NYC sites. V: Fe ratios remarkably similar among
    sites. Fe levels fixed at NYC level of 16 pm
    (highest).
    
    IRP: Coexposure with 3 metals increased IRP
    binding activity relative to Fe(lll) alone, by up to 3.5
    fold for Al (1.5-3 ratio), 2 fold for Mn (0.08-0.2 ratio)
    and 7 fold for V (0.2 ratio). IRP activity dropped at
    higher ratios. A drop in IRP activity at higher ratios
    may be result of cytotoxicity forAI, but not for V and
    Mn.
    
    iNOS: Al induced iNOS expression dose-
    dependently There was no observed effect for Mn
    andV.
    
    Induction of Hypoxia-inducible Factor (HIF-1a):
    Only V and Al induced HIF-1a.
    
    Activation of ERK1 and -2: V and Al induced
    pERK1,  but only V induced pERK2. Mn had no
    increasing effects,  but data indicated a decreasing
    induction.
    December 2009
                                                    D-65
    

    -------
           Study
                Pollutant
    Exposure
    Effects
    Reference: Ramage
    and Guy (2004,
    0556401
    
    Species: Human
    
    Cell Type:  A549
    PM10: Collected in Wolverhampton, UK  Route: Cell Culture
    
    ufCB: Ultrafine Carbon Particles        Dose/Concentration: 80 pg/mL
    
    (Origin not reported)                  Time to Analysis: 0, 0.5, 3, 6,18 h
    
    Particle Size: PMi0, ufCB: <100 nm
    (diameter)
                             CRP: Treatment with ufCB or PMio produced an
                             increase in CRP expression with similar effects
                             noted after 6 h. PM10 induced greater increases than
                             ufCB. Both the cytoplasm and nucleus contained
                             CRP.
    
                             Hsp70: PMio and ufCB induced increased levels at
                             all time points with ufCB inducing greater levels than
                             PMi0. Hsp70 expression was observed in the
                             cytoplasm and nucleus.
    
                             Antioxidants  of CRP and Hsp70: Coincubation  of
                             ufCB with Nacystelin and Trolox caused a small
                             reduction in CRP and Hsp 70.
    Reference: Rao et al.
    (2005, 0957561
    Species: Rat
    Strain1 9D
    wllallK OLJ
    Cell Type: AMs and
    cultured lung
    fibroblasts
    Reference: Reibman
    et al. (2003, 1569051
    Species: Human
    
    Cell Type: HBEC,
    BEAS-2B
    
    DEP: SRM 2975 (NIST)
    Particle Size: 05 |jm
    
    
    
    
    
    UFPM: Ultrafine PM
    FPM:FinePM
    
    IPM: Intermediate PM
    CPM: Coarse PM
    CB: Carbon black
    Route: Cell Culture
    Dose/Concentration: 200 |jg/mL
    Time to Analysis: 4 h
    
    
    
    
    Route: Cell Culture
    Dose/Concentration: 11 pg/cm2; 100 pg/mL
    
    Time to Analysis: 6, 18 h
    
    
    mRNA Expression: No change in IL-1 13 or iNOS
    were observed. Data suggests that the lung
    fibroblasts is the main source of IL-6 and MCP-1 in
    BAL fluid because of their comparatively high
    message levels. Due to the extreme variability in
    results, the cause of an increase on co-culture with
    AMs and/or DEPs was not assessed.
    
    
    Cytotoxicity: After treatment, cells were more than
    90% viable. UFPM and FPM caused no gross
    alterations in cell morphology or adhesion.
    
    MIP3o/CCL20 mRNA (6 h): Stimulation of mRNA
    released by HBEC upon exposure to UFPM
    appeared similar to that provided by TNF-a (5
    |jg/mL) and IL-1 13 (10 mg/mL).
                         All PM collected 8th floor, 26th St and
                         IstAve, New York City, NY
    
                         Particle Size: UFPM: <0.18 pm; FPM:
                         0.18 -1.0 pm; IPM: 1.0-3.2 pm; CPM:
                         >3.2 pm
                                                                              MIP3|3/CCL20 protein in HBEC (18 h): TNF-a and
                                                                              IL-113 induced a dose-dependent increase in
                                                                              MIP3o/CCL20 protein (0-10 ng/mL), whereas II-4
                                                                              and IL-13 induced MIP3a/CCL20 protein release
                                                                              that reached maximum levels at 1 ng/mL. No
                                                                              release of MIP1a/CCL3 nor RANTES/CCL-5 was
                                                                              observed upon stimulation with cytokines.
    
                                                                              Secretion of MIP3o/CCL20 in response to PM (18
                                                                              h): All PM fractions less than 2.5 pm resulted in the
                                                                              release of MIP3a/CCL20 protein in HBEC roughly
                                                                              equivalent amounts. CB similar in size to UF/fme PM
                                                                              did not result in the release of MIP3o/CCL20, nor did
                                                                              LPS (0.01-1.0  |jg/mL). No release of MIP1o/CCL3
                                                                              nor RANTES/CCL 5 was observed upon stimulation
                                                                              by PM fractions.
    
                                                                              Activation of MAPK (ERK1/2 and p38): ERK1/2
                                                                              and p38 was activated by TNF-a, IL-lp, IL-4and IL-
                                                                              13 within 15 min and was sustained for at least 60
                                                                              min. Erk1/2 and p38 inhibitors reduced
                                                                              MIP3o/CCL20 release in BEAS-2B cells in response
                                                                              to cytokines.
    December  2009
                                                  D-66
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Riley et al.  Zn: ZnCI2
    (2003, 0532371
    Species: Rat
    
    Cell Type: RLE-6TN
    (Type 11 Alveolar
    Epithelial Cells)
    Cu: CuCI2
    
    Fe: FeCI2
    
    V: VCI4
    
    Ni:NiCI2
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 0.01, 0.1,1.0,10 mM
    
    Time to Analysis: 2, 4, 24, 72 h
    Cytotoxicity (SDH): All particles were cytotoxic in a
    dose-dependent manner. Zn and V were cytotoxic at
    0.05 mM, Cu at 0.5 mM, Ni at 0.8 mM and Fe at 2
    mM. ForZn, cell death (LDH) had a biphasic
    response: a slow logslope until approx 0.1 mM at
    which point it rapidly accelerated to a peak at 5 mM
    with a small decline at 10 mM. Most of Zn
    cytotoxicity was not due to apoptosis. IPS did not
    affect either Zn or Cu cytotoxicity.
    
    Metabolism Inhibition Time Course Response
    (Cu and Zn only): At high (1 mM) concentrations,
    Zn toxicity peaked  at 36-48 h followed by a 2-fold
    recovery by 72 h. Cu showed a faster,  steady
    decline plateauing  after 36 h. At low concentrations
    (0.1 mM), Cu showed a steady slow decline. At 48 h,
    Zn decreased faster to max activity and returned to
    control by 72 h.
    
    IL-6 Secretion: Zn and Cu both decreased IL-6
    secretion. Decreases were very similar for both
    metals and concentrations when expressed as
    secretion per viable cell ratio except for Zn at 1.0
    mM.
    
    Metal Combinations: Zn and Cu gave variable
    results. Zn protected against V cytotoxicity. Zn and
    Cu  had an additive response. Zn did not affect Fe
    toxicity.
    Reference: Riley et al.  Fe: FeCI2
    (2005, 0964521
    v	'        Ni: NiCI2
    Species: Rat, Human
                         Cu: CuCI2
    Cell Type: RLE-6TN,
    NR8383 Alveolar      V:VC|2
    Macrophages, A549
                         Particle Size: NR
                                        Route: Cell Culture (5x104 cells/well
                                        Alveolar Cells; 1.2x105 cells/well NR8383)
    
                                        Dose/Concentration: AMs: 0.02, 0.05,
                                        0.07, 0.08 mM; RLE-6TN: 0.1, 0.2, 0.6, 1.0,
                                        6.0mM;A549:0.5, 0.8,  4.4, 4.8 mM
    
                                        Time to Analysis: 2-48 h
                                            Relative Sensitivity of Cell Strains to Metal
                                            Chloride: NR8383 was more sensitive than RLE-
                                            6TN and A549 except for V where
                                            NR8383 and RLE-6TN were both more sensitive
                                            thanA549.
    
                                            Relative sensitivity of Cell Strains to Metal
                                            Chloride vs Sulfate: With the exception of Cr,
                                            sulfate was generally more cytotoxic than chloride
                                            (note V valence state).
    
                                            A649 Cytotoxicity Time Course: Zn cytotoxicity
                                            takes 24 h to develop whereas Cu cytotoxicity
                                            develops within 2 h. LDH release for Cu, however,
                                            develops in 24 h.
    
                                            RLE Cytotoxicity Time  Course: Zn starts at 2 h
                                            and develops until 24 h.  Cu develops within 2 h and
                                            continues until 24 h where it is less toxic than Zn.
                                            Both release equivalent amounts of LDH after 24 h.
    
                                            NR8383 Cytotoxicity Time Course: Both Zn and
                                            Cu exhibit time dependent toxicity beginning as early
                                            as 4 h. LDH release maximizes at 12 h and either
                                            remains steady or declines.
    Reference: Ritz et al.
    (2007,1989011
    
    Species: Human
    
    Cell Type: BEAS-2B,
    NHBEC
    DX: Extract of DEP (generated from a
    light duty four-cylinder diesel engine
    4JB1 type  Isuzu Automobile)
    
    Particle Size: <1  pm (diameter)
    Route: Cell Culture
    
    Dose/Concentration: 0, 20, 50,100 pg/mL
    
    Time to Analysis: 24 h
    NQ01 (Sentinel Phase II Enzyme): Cells
    transfected with NQ01  reduced induction of IL-8 by
    DX exposure.
    
    Sulfurophane: Increased gene expression of phase
    II enzymes, particularly NQ01, was observed in both
    cell types. Gene expression in BEAS-2B was greater
    than that of NHBEC.
    
    Sulfurophane did not upregulate GSTM1 in BEAS-
    2B but induced a 2-fold increase in NHBEC.
    Pretreatment also inhibited DX-induction of IL-8 in
    both cell types.
    
    Cytokines: DX induced significant increase of IL-8
    in both cell types at concentrations of 10 pg/mL or
    higher. GM-CSFand IL-8 remained unaffected in
    BEAS-2B. GM-CSFand IL-8 Increased in NHBECs
    and reached statistical significance at 25 pg/mL
    December 2009
                                                    D-67
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Rosas
    Perez et al. (2007,
    0979671
    Species: Mouse
    
    Cell Type: J774A.1
    PM10
    
    Collected in Mexico City, Mexico from
    January-June, 2002
    
    North: Iztacala, manufacturing industry;
    
    Center: Merced, heavy traffic;
    
    South: Ciudad Universitaria, residential
    
    Principal Component Analysis of Air
    Pollution Data:
    
    Group 1:S/K/Ca/Ti/Mn/Fe/Zn/Pb (43%
    of variance);
    
    Group2:CI/Cr/Ni/Cu(16%);
    
    Group 3: Endotoxins/OC/EC (14%).
    
    For all 3 sites: Averages of Group 1 is
    statistically different among the center,
    north and south sites with the central
    site producing the highest values.
    Group 2 is similar among the sites and,
    for Group 3, the north had a lower
    average than the center and south
    sites.
    
    Particle Size: PM10
    Route: Cell Culture (1.5x104 cells/cm2)
    
    Dose/Concentration: 20, 40 or 80 pg/cm2
    
    Time to Analysis: 72 h
    Cytotoxicity: Responses were dose-dependent;
    there was no observed site interaction. Cytotoxicity
    seems to be a result of the following components:
    S/K/Ca/Ti/Mn/Fe/Zn/Pb.
    
    IL-6: Only the center site at 40 pg/cm2 induced an
    increase. Induction of  higher IL-6 levels seems to be
    related to high values  of S/K/Ca/Ti/Mn/Fe/Zn/Pb and
    endotoxins/OC/EC.
    
    TNF-a: Production was induced by all samples  in a
    dose-dependent manner. Similar to IL-6, induction of
    higher TNF-a levels seems to  be a result of high
    values of S/K/Ca/Ti/Mn/Fe/Zn/Pb and
    endotoxins/OC/EC.
    
    p63: Only south PM had effect. Induction of p54
    seems to depend on high levels of CI/Cr/Ni/Cu and
    low levels of S/K/Ca/Ti/Mn/Fe/Zn/Pb.
    Reference: Sakamoto  PM,0: EHC-93 (Obtained from Health
    etal.  (2007, 0962821   Canada, Canata)
    Species: Human
    
    Age: 58-82 yr
    (Smokers)
    
    Cell Type: HBEC
    Particle Size: PM10
    Route: Cell Culture
    
    Dose/Concentration: 100, 300 and 500
    pg/mL
    
    Time to Analysis: Calcium responses: up to
    60 min; cytokines: 6 or 24 h
    Intracellular [Ca2+]: [Ca] concentration slowly
    increased, elevating after 10 and 30 min for 500 and
    300 mg/mL, respectively. The response plateaued at
    35 min for 500 pg/mL.
    
    Extracellular [Ca2+]: Starting at 20 min, the
    removal of extracellular Ca decreased the PM10
    response significantly. Calcium channel blocker
    (10|jM or 1mM) LaCIS and  (5mM) NICI2 significantly
    blocked the PM-induced intracellular Ca. Lacl2
    administration (1mM) inhibited the PM-induced
    Ca2+ response in a dose-dependent manner.
    
    Mode of Action: Intracellular Ca induced by ATP
    declined more slowly in the cells exposed by PM10.
    This indicates that PMio blocks Ca clearance via the
    calcium pumps.
    
    Cytokines: PMio induced a dose-dependent
    increase in cytokine mRNA levels and  cytokines IL-
    1P, LIF,  IL-8 and GM-CSF.  Cytokine expression was
    unaffected by the reduction of extracellular Ca2+ .
    Preincubation with the calcium chelator reduced
    responses for IL-lp and IL-8 but not LIF or GM-CSF.
    Reference: Salnikow
    et al. (2004, 0874691
    
    Species: Human
    
    Cell Line: 1 hAEo-
    FeS04
    
    FeCI3
    
    NiS04
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 0.25 and 0.5 mM
    
    Fe exposures also contained 60 pg/mL
    apotransferrin
    
    Time to Analysis: 24 h
    Cytotoxicity: Both Fe had no effect. NiS04 caused
    marginal Cytotoxicity (75%).
    
    Hypoxic Stress: At 20 h, NiS04 (at concentrations
    of 0.25 or 0.5 mM) induced NDRG-1/Cap43 protein
    production indicating hypoxic stress. DFX and
    DMOG induced a similar effect.
    
    IL-8: NiS04 induced IL-8 time-dependently for up to
    48 h. At 48 h, the increase was 6+ fold.
    
    Coexposure (Ni + Fe) on Fe uptake: Fe(lll)  uptake
    was greater than Fe(ll) uptake. NiS04 had no effect.
    Ni uptake was greater than Fe uptake but was
    decreased by coexposure to Fe. Coexposure also
    did not effect hypoxic stress. Coexposure with Fe
    did reduce Ni-induced IL-8 production.
    December 2009
                                                    D-68
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Salonen et PMi0 (urban traffic) Finland            Route: (2^10 cells/well)
    al  (2004  1870531
           '	      Pooled as winter (W), spring I (SI), or   Dose/Concentration: 15, 50,150, 500,
    Species:  Mouse       spring II (Sll) based on component/time  1000|jg/mL
                         considerations
    Cell Type: RAW 264.7                                      Time to Analysis: 0, 24 h
                         Particle Size: PM10:  0.12-10 pm
                                                                                Air quality parameters: Winter and spring I did not
                                                                                differ. Sll much lower PM25
    
                                                                                Metal data equivocal as well as highly variable
                                                                                resuspension rates.
    
                                                                                Total PAHs:  W=303; Sl=233; SI 1=204 ng/mg
    
                                                                                Inflammation (IL-6, TNF-o, N0)/Cytotoxicity: A
                                                                                dose-dependent increase was observed for TNF-a,
                                                                                IL-6 and NO except for SI. The IL-6 levels, of those
                                                                                particles exposed to SI, decreased at 1000 pg/mL
    
                                                                                TNF-a, IL-6: SI = SI l»W>control.
    
                                                                                NO production: W>SI>SII
    
                                                                                Cell Viability: W=SI=SII toxic at 500 and 1000
                                                                                pg/mL
    
                                                                                Water-soluble vs Insoluble: TNF-a and IL-6 were
                                                                                nearly entirely the result of insoluble components of
                                                                                PM10. Cytotoxicity was driven by both soluble and
                                                                                insoluble components.
    
                                                                                Metal Chelation: The addition of metal chelators did
                                                                                not modify IL-6, TNF-a or cytotoxicity
    
                                                                                IPS inhibitor: Treatment with the LPS inhibitor
                                                                                eliminated the IL-6 response and,  perhaps, slightly
                                                                                reduced the TNF-a response but not cytotoxicity
    
                                                                                Hydroxyl radicals: A dose-dependent induction of
                                                                                hydroxyl radicals and induction of hydroxyl  radical
                                                                                lesions (at 500 and 1000 pg/m ) in the calf thymus
                                                                                DNA were observed.
    Reference: Samet et   As: NaAS03
    al. (2003, 1137821
    Species: Human
    
    Cell Type: A431
    (Epidermoid Cells)
    V: VOS04
    
    Zn: ZnS04
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 5QQ|j[vl
    
    Time to Analysis: 20, 30 or 90 min
    EGFR Dimerization: Zn, V or As did not induce
    EGFR dimerization in a cell free system i.e., no
    direct crosslinking. Zn did not induce dimerization in
    whole cells either.
    
    Phosphorylation of EGFR: Zn induced
    phosphorylation at 3 sites similar to EGF As and V
    had no effect.
    
    EGFR Kinase Inhibitor: While EGF action was
    blocked, Zn continued to induce phosphorylation
    and was independent of EGFR kinase activity.
    
    c-Src: Blocking of c-Src tyrosine kinase
    (transactivator of phosphorylation) negated all Zn-
    induced phosphorylation but only had a slight effect
    on EGF stimulated cells.
    
    ERK1/2 Phosphorylation: Zn increased levels of
    ERK1/2. Pretreatment with EFGR kinase inhibitor
    reduced both Zn and EGF effect. This effect was not
    blocked by the c-Src blocker.
    Reference: Santini et  DEP: Collected adjacent to moderate
    al. (2004, 0878791     traffic in Rome, Italy
    
    Species: Mouse       Particle Size: PM25
    
    Cell Type: RAW 264.7
                                        Route: Cell Culture (2.5x105 cells/ml)
    
                                        Dose/Concentration: 0.01, 0.1,1.0 pg/mL
    
                                        Time to Analysis: 24 h
                                            600 MHz Results (no 1 ug/mL): DEP induced a
                                            dose-dependent increase in choline compounds, a-
                                            and pgamma- glutamine/glutamate (0.01 >0.1
                                            pg/mL), lactate, and CH2, CH3 moieties of fatty
                                            acids. DEP decreased inositol and
                                            phosphoreatinine.
    
                                            700 MHz Results (no 1 ug/mL): DEP induced
                                            similar results, except a-,  pgamma-glutamine were
                                            dose-dependent. Inositol showed no effect. Taurine
                                            slightly increased. Results were confirmed after
                                            eliminating biological interferences via perchloric
                                            acid.
    
                                            Growth Curves/Cell Cycle Analyses/Cell
                                            Morphology: DEP had no effect.
    
                                            Cytokines: IL-6 levels increased at 0.1 and 1
                                            pg/mL TNF-a was unaffected.
    December 2009
                                                    D-69
    

    -------
           Study
                Pollutant
                  Exposure
                                                               Effects
    Reference: Saxena et  DEP: SRM 1650
    al. (2003, 0969861
    Species: Mouse
    
    Cell Type: RAW 264.7
    CO: Crude Organic Extract of DEP
    
    Fractionated into
    
    asphaltene (pentane/hexane),
    
    saturated hydrocarbon,
    
    less polar (aromatic) hydrocarbon,
    
    more polar (aromatic) hydrocarbon,
    
    resins, residual (resins)
    
    Particle Size: NR
    Route: Cell Culture (2.5*104 cells/ml)       Cytotoxicity: No cytotoxic effects were observed.
    
                                            NO: DEP alone induced NO in a dose-dependent
                                            manner which peaked after 1 day and plateaued for
                                            days 2 and 3. IFN-y + DEP showed dose- and time-
                                            dependency. IPS + DEP showed no effect at 1 day,
                                            but dose-dependently reduced NO production on
                                            days 2 and 3. Addition of Bacillus Calmette-Guerin
                                            (BCG) eliminated the effect of DEP at 2 days but
                                            showed a dose-dependent decrease at 3 days.
    
                                            Effectiveness of Particulate Components: The
                                            carbonaceous core of DEP did not affect BC G-
                                            stimulated NO production. CO significantly inhibited
                                            BCG-stimulated  NO production. Study indicated that
                                            the extract of aromatic hydrocarbons and resins
                                            caused an inhibitory effect in a dose-dependent
    Dose/Concentration: DEP, CO 5,10,15,
    20, 25 pg/mL
    
    IFN-y: 10 ng/mL
    
    IPS: 1 mg/mL
    
    Time to Analysis: 1-3 days
    Reference: Seagrave
    et al. (2007, 0975491
    
    Species: Human
    
    Gender: Male (3
    donors)
    
    Age: 16, 23 yr
    
    Cell Type: A549
    DE: Generated by DE 5500 watt
    generator using #2 certification oil
    performed under SOOOw load.
    Emissions diluted to 3 mg/m3 total
    particulate matter.
    
    Particle Size: 0.14-0.5pm
    Route: Air Liquid Interface
    
    Dose/Concentration: 8.33 mL/min/well
    
    Time to Analysis: 3 h exposure; 1 or 21  h
    post-exposure
                                            Particle Deposition: 140 and 500 nm microspheres
                                            demonstrated uniform deposition of approx. 10%.
    
                                            Transepithelial Electric Resistance: No effect of
                                            DE; rather, more effect was observed from air
                                            controls.
    
                                            Macromolecular permeability: DE caused an
                                            increase 1 h but returned to control at 21 h.
    
                                            LDH/Cytotoxicity: DE had a highly variablefdonor
                                            specific) effect at  1 h and returned to  control levels
                                            at 21 h
    
                                            Mitochondria! activity (WST): DE reduced activity
                                            at 1 h and possibly increased activity  at 21 h (high
                                            donor-to-donor variability)
    
                                            Mucus Like Substance Excretion: There was high
                                            donor to donor variability;  no overall effects were
                                            observed.
    
                                            Alkaline Phosphatase (AP): DE decreased at 1 h
                                            and perhaps increased at 21 h
    
                                            Glutathione: DE  caused a large decrease at 1 h but
                                            returned to normal at 21 h.
    
                                            HO-1: After DE exposure, levels increased but were
                                            still lower than air exposed controls
    
                                            Cytokines: No differences for IL- 8 or 12, TNF-a,
                                            GM-GSF, IL-1a, or IFN-y were observed. IL-4 and -6
                                            were decreased upon DE exposure.
    Reference: Seagrave
    et al. (2004, 0874701
    
    Species: Human
    
    Cell Type: A549
    DPM: SRM2975 (NIST)
    
    DPM-0: DPM organic extract
    (acetone/DCM)
    
    CB: Carbon Black (Elftex-12, Cabot)
    
    Particle Size: CB: 37 nm; Stokes
    diameter! 98 nm
    Route: Cell Culture (1 xlOb cells/well)
    
    Dose/Concentration: 0.03 -1,000 pg/cm2
    
    Time to Analysis: 0,18 h
                                            IL-8 release: DPM increased semi dose-
                                            dependently (perhaps steady based on error range)
                                            up to 1 pg/cm after which IL-8 declined dose
                                            dependently to zero (control = 100%) at 300 and
                                            1000 pg/cm2. LDH release was steady which
                                            indicates no cytotoxicity.
    
                                            DPM interaction with IL-8: DPM depletes IL-8 from
                                            solution in a dose-dependent manner (cell free).
                                            BSA preincubation reduced the slope of the dose
                                            response but not the final result.  CB has no effect.
                                            DPM-0 residuals act identical to  DPM. Increasing
                                            NaCI concentrations reduced DPMs depletion of IL-8
    
                                            Neutrophil  responses: DPM and bound IL-8
                                            together caused a marked aggregation of cells
                                            resulting in spindle shapes. DEM or IL-8 alone did
                                            not cause this aggregation although DEP did recruit
                                            neutrophils
    December 2009
                                                    D-70
    

    -------
           Study
                                      Pollutant
    Exposure
    Effects
    Reference: Seagrave   PM filter collection
    et al. (2003, 0549791
                          Collected from diesel or gasoline
    Species: Human, Rat   powered vehicles as follows:
    
    Cell Line: F344/&I BR  BG: BS Gasoline
    
                   G30: Normal Emitter gasoline (30F)
    Age: 11 wk (mouse)
                          G: Normal emitter gasoline (72F)
    
                          HD: High Emitter Diesel
    
                          D30: current technology diesel (30F)
    
                          D: current technology diesel (72F)
    
                          WG: White Smoke Gasoline
    
                          Particle Size: NR
                                                              Route: Cell Culture (1 xlOb cells/well)
    
                                                              Dose/Concentration: 0.03-10,000 pg/cm2
    
                                                              Time to Analysis: 16-18 h
    Weight: 250 g
    
    Cell Type: A549, AMs
                              Cytotoxicity: LDH activity increased in A549 cells.
                              The types of pollutants that are most toxic, in
                              decreasing order of cytotoxicity, are the following:
                              BG, G30, and G which are significantly different from
                              HD, D30, D, WG which are also significantly
                              different from DS. LDH activity also increased in rat
                              macrophages. G, G30, and BG were the most toxic.
                              HD and D30 were intermediately toxic and D, WG,
                              and DS were the least toxic. In both cell types,
                              gasoline was more cytotoxic than diesel.
    
                              Cytokines: All particle types except DS increased
                              IL-8 levels in A549 though not all increases were
                              statistically significant. Also, many particle samples
                              at high concentrations produced an apparent
                              suppression of IL-8 release.
    
                              Alkaline Phosphatase: G30 and G were more
                              potent than the other particle samples in A549. WG
                              and D30 induced no significant effects. For A549
                              cells, activity increased at low concentrations and
                              was suppressed at higher concentrations.
    
                              Macrophage Peroxide Production: In rat AMs,
                              peroxide production was often the highest at the
                              lowest concentrations and the lowest production
                              caused by the highest concentrations. D30 followed
                              this trend and induced the highest production as well
                              as the greatest suppression. Using two different
                              statistical methods,  D30 >6 others which in turn
                              >DS. Using the second method D30 and D >all other
                              6. Order of potency between two methods
                              completely different. Authors noted that in vitro
                              potency quite different from in vivo potency
                              (previous paper).
    Reference: Seaton. et  PM25 from London                    Route: Cell Culture
    al  (2005 1989041
                          PM10 from Manchester (positive control)  Dose/Concentration: 1-100 pg/mL
    Species: Human
    
    Cell Type: A549
                          PM from Holland Park, Hampstead and  Time to Analysis: Cytotoxicity: 24 h; IL-8:
                          Oxford Circus stations (HP, HR and      h; Generation of hydroxyl radicals: 8 h
                          OC)
    
                          Particle Size: PM25,PM10, Holland
                          Park, Hampstead and Oxford Circus
                          PM had a median diameter of 0.4 pm.
                          80% of the particles had a diameter
                          less than 1 pm.
                              Cytotoxicity: Dust from all three tunnels (Holland
                              Park, Hampstead and Oxford Circus) were able to
                              cause cell death (LDH). The release of LDH
                              indicated a dose-dependent relationship. The
                              highest dose of Holland Park PM induced the -17%
                              release of LDH, Hampstead triggered ~ 13% and
                              Oxford Circus -3% (no different than control). PM10
                              from Manchester caused a 7% LDH release at the
                              highest dose. The  negative control (Ti02) caused no
                              response (2% release at highest dose).
    
                              IL-8: All three tunnel PMs induced  a dose-
                              dependent release of IL-8. At the highest dose, all
                              three tunnel dusts  induced IL-8 stimulation more so
                              than the control site PM25. HP induced  a 3 fold
                              increase. Also,  the highest Ti02 concentration
                              caused the least IL-8 stimulation.
    
                              Hydroxyl Radical Generation/ DMA Plasmid
                              assay: The plasmid assay indicated that the tunnel
                              dusts induce more free radical activity than the
                              Manchester PMi0 and Ti02.
    
                              HP nearly doubled the percentage of DNA damage
                              with intermediate results for HR and OC. Results for
                              PM10, Ti02 and control were identical
    December 2009
                                                                          D-71
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Singal and AE2:Aerosil 200, amorphous silica      Route: Cell Culture (5^10 cells/well)
    Finkelstein (2005,
    1989051
    
    Species: Human,
    Mouse
    
    Cell Type/Line:
    A549Lud lung
    adenocarcinoma
    epithelial cell line
    (human), MLE15Lud
    and MLE15Luc2
    (mouse)
    
    All cells contain human
    cytokine IL-8
    controlling firefly
    luciferase
    (Degussa)
    
    Cl: Carbon iron particles (25% Fe)
    Dose/Concentration: 18 pg/mL, 36 pg/mL,
    72 pg/mLall in 1 ml/well
    Particle Size: AE2:12 nm surface area  Time to Analysis: 24 h
    ~200±25m2/g;CI:~40nm
    Luc Activity: Luciferase enzyme activity is
    significantly less in MLE15Luc2 cells than in
    MLE15Lud cells. For both cells, luciferase activity is
    time- and dose-dependent peaking at 4-8 h.
    
    Aerosil 200: AE2 induced dose- and time-
    dependent Luc response which peaked at 3 h and
    decreased thereafter in a similar way as TNF-a.
    Contrary to TNF-a, AE2 induced much cytotoxicity
    starting at 6 h.
    
    Effect of Proteasomal Inhibitors (MG-132):
    Inhibitor reduced AE2 Luc activity to near control
    levels. Similarly, LDH-cytotoxicity was halved
    
    A649 Human Cell Response: AE2 acted similarly
    to the MLE response. Cl particles showed slightly
    less activity without peaks. AE2 increased
    cytotoxicity after 12 h, whereas Cl had no effect.
    
    Contrary to MLE mouse, MGJ32 did not affect Luc
    activity but PD98059 (selective noncompetitive
    inhibitor of the MAP pathway) and SN50 (NF-KB
    inhibitor) reduced AE2 and Cl-induced activity.
    Reference: Song et al.
    (2008, 1560931
    
    Species: Rat
    
    Cell Type: RAW 264.7
    DEP collected from a 4JB1-type, light-
    duty (2740 cc), four-cylinder diesel
    engine operated using standard diesel
    fuel at speeds of 1500 rpm under a
    load of 10 torque.
    
    Particle Size: 0.4 pm (mean diameter)
    Route: Cell Culture (5x10  cells seeded on
    a 24-well plate)
    
    Dose/Concentration: 50 |jg/mL
    
    Time to Analysis: 72 h
    Nitrite Production: 50 pg/mL of DEP induced
    production when compared to the control. Over the
    72 h period, a general trend was not observed, but
    maximal induction of nitrite occurred at 4 h after
    stimulation.
    Reference: PMC: PM Coarse
    Steerenberg et al.
    (2006, 088249) PMF: PM "ne
    Species: Rat, Human Ambient air samples collected from
    Route: Cell Culture
    Dose/Concentration: NR
    Time to Analysis: 20 h
    Crustal material (metals and endotoxin but not Ti,
    As, Cd, Zn, V, Ni, Se) were positively associated
    with AM IL-6 and TNF-a and Type 2 MIP-2 and IL-6.
    Sea spray (Na and Cl) was also correlated with AM
    IL-6.
    Cell Type: AM (rat),
    Type 2 cells (rat), A549
    Poland; Amsterdam, the Netherlands;
    De Zilk, the Netherlands.
    
    Particle Size: PMC: 2.35-8.5 pm; PMF:
    0.12-2.35 pm
    Reference: Tal et al.
    (2006, 1085881
    
    Species: Human
    
    Cell Type: HAEC
    100 mM Zn(ll) orV(IV) stock solutions
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 500 pmol
    
    Time to Analysis: 5, 20 min
    Zn-mediated EGFR Phosphorylation: EGFR
    kinase activity was required but not EFGR ligand
    binding. EGFR Kinase inhibition reduced Zn
    mediated EGFR activation, (authors NOTE:
    complete reverse of results in B82L and A431 cells).
    Src Kinase is not required. Zn inhibiting Src kinase
    was nearly total after 20 min.
    
    EGFR-Specific Protein Tyrase Phosphatase
    (PTP): Zn inhibited PTPs, similar to V(IV) resulting in
    a decrease of exogenous EGFR dephosphorylation
    Reference: Tamaoki et UFCB: Ultrafine Carbon Black - (Tokai   Route: Cell Culture (104 cells/well)
    al. (2004,1570401     Carbon, Japan)                                         .,^,,0,^c
             	                                          Dose/Concentration: 6.1,12.3,18.4, 24.5,
    Species: Human      FCB: Fine Carbon Black (Tokai Carbon,  30.7 pg/cm2
                         Jaoanl
    Cell Type: HBEC                                          Time to Analysis: Up to 72 h
                         Particle Size: UFCB: 11+0.5 nm
                         (mean diameter)
    
                         FCB: 250+16 nm (mean diameter)
                                                                               DMA Synthesis/ Protein Synthesis: Synthesis
                                                                               increased by UFCB (30.7) for up to 72 h and
                                                                               flattened after 48 h. FCB had no effect. UFCB also
                                                                               showed a dose-dependent response beginning at
                                                                               12.3 pg/cm2 up to 24.5 after which the response
                                                                               plateaued. The addition of Cu/Zn Super oxide
                                                                               dismutase (SOD) or a NADPH oxidase inhibitor
                                                                               completely inhibited the UFCB effects. Similarly, two
                                                                               different EGFR tyrosine kinase inhibitors, and a Me
                                                                               inhibitor all reduced UFCB response to control
                                                                               levels.
    
                                                                               ERK activation: UFCB caused phosphorylation of
                                                                               ERK beginning at 2 min, peaking at 5 min and
                                                                               decreasing at 10 min. ERK activation was inhibited
                                                                               by EGFR tyrosine kinase inhibitor Cu/Zn SOD and
                                                                               neutralizing body for HB-EGF but not by PDGF-R
                                                                               kinase inhibitor.
    
                                                                               HE (polyclonal heparin binding)-EGF release:
                                                                               UFCB induced rapid cell surface loss with recovery
                                                                               after 20 min and nearly full recovery at 360 min.
                                                                               Metalloproteinase inhibitor and Cu/Zn SOD both
                                                                               prevented HB-EGF release.
    December 2009
                                                   D-72
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Tao and    UAP: Urban Air Particles (SRM 1649)
    Kobzik (2002, 1570441
    Species: Rat
    
    Cell Type: RLE-6TN
    (Alveolar Type II
    Epithelial Cells), Fetal
    Lung Fibroblasts
    (RFL), AMs
    Ti02
    
    Si02
    
    ROFA
    
    Particle Size: Ti02: ~1 pm; Si02: ~1
    pm; ROFA: NR
    Route: Cell Culture (1x1 Ob cells AM
    
    1.4x105 cells RLE/RFL)
    
    Dose/Concentration: 1-50 pg/mL
    
    Time to Analysis: 24 h
    Cytokines: TNF-a and MIP-2 in RLE was
    unaffected by any particle samples. TNF-a and MIP-
    2 in AM significantly increased with 25 pg/mL UAP.
    TNF-a and MIP-2 in the co-culture of AM + RLE
    increased with each particle. The order of particles
    in decreasing order are as follows: Si02 at 25pg/mL,
    UAP at 12.5 fjg/mL, ROFA at 25 pg/mL, and Ti02 at
    50 pg/mL Except for Si02, the blocking of effects
    caused by LPS absorbed on the particles did not
    affect the cytokine response. For Si02, the response
    was reduced but still above the control.
    
    Co-culture: Physically separating AM and RLE cells
    and adding PM completely negated the co-culture's
    response to PMs. This indicates that cell to cell
    contact is required for co-culture potentiation of PM
    effects.
    
    Inhibitors: Various inhibitors of cell adhesion
    molecules (heparin, p -1, 2 or 3 integrin) had no
    effect on UAP-induced cytokine release.
    Reference: Veranth et  Artificial particles and PMs
    al. (2007, 0903461
                         N-AI: nano alumina AI203
    Species: Human
    
    Cell Type: BEAS-2B,
    A549, NHBE
    M-AI: Micro AI203
    N-Ce: nano Ce02
    M-Ce: micro Ce02
    N-Fe: nano Fe203
    M-Fe: micro Fe203
    N-Ni: nanoNiO
    M-Ni: micro NiO
    N-Si: nano Si02
    M-Si: micro Si02
    N-Ti: nanoTi02
    M-Ti: micro Ti02
    KLN: kaolin
    
    MUS: Min-U-Sil (ground crystalline
    silica)
    
    DD: desert rural soil Utah PM25
    
    JE: Juarez, urban street PM25
    
    MNC: Mancos, rural Utah PM25
    
    LPS: lipopolysaccharide
    
    V:VOS04 (soluble) (19 pg/mL)
    
    Particle Size: (Surface mean diameter)
    
    N-AI: 6 nm (261 nf/gl
    M-AI: 210 nm (7.7 nf/g)
    N-Ce:14nm(71 m2/g)
    M-Ce:1500nm(0.6m2/g)
    N-Fe: 5 nm (221 m2/g)
    M-Fe:100nm(12nf/g)
    N-Ni:6nm(145m2/g)
    M-Ni: 16nm(57nf/g)
    N-Si: 19 nm (127(11%)
    M-Si: 440 nm (5.4 m7g)
    N-Ti: 6 nm (242 m2/g)
    M-Ti: 410 nm (3.5 nf/g)
    KLN: 100 nm (24.3 nf/g)
    MUS: (NOS <5 pml
    DD: 400 nm (6.2 m /g)
    JE: (NOS <3 fjm)
    MNC: 200  nm  (13.0 nf/g)
    Route: Cell Culture (35,000 cells/cm2 BEAS;
    2500 cells/cm2 NHBE; 20,000 cells/cm2
    A549)
    
    Dose/Concentration: 0.53, 5.3 and 53
    |jg/cnf(=1,10,100|jg/mL)
    
    Time to Analysis: 24 h
    Cell Viability: Except for Ni and V no cytotoxicity
    was observed at the highest concentration.
    
    IL-6 Secretion in BEAS-2 B Cells: Nano and micro
    sizes of the same metal showed no differences in
    response (high experiment to experiment variability).
    In general, the soil-derived dusts (JE, DD, MNC)
    were more potent than the metal and ceramic oxide
    particles.  In KGM media, BEAS-2B cells are more
    responsive to vanadium and other soluble metals
    and less responsive to LPS, but this relationship is
    reversed  in LHC-9 media.
    
    IL-8 Secretion in BEAS/LHC vs NHBE in BEGM
    Cells: Levels were much higher in NHBE cells than
    BEAS-2B cells. For BEAS-2B, the nano size Si and
    both sizes of Ni induced levels statistically greater
    than the control. For NHBE, only Si and Ni (for both
    sizes) were statistically greater than control.
    
    IL-6 in NHBE: The nano and micro sized particles of
    Al, Ce, Fe and nano sized Si all induced statistically
    significant increases. Control levels of IL-6 were
    much  higher  in NHBE cells than in BEAS-2B cells.
    Secretion induced by pure oxide  particles was small
    for both the mid and high concentration levels (5.3
    and 53 pg/cm ).
    
    BSA/  Bovine Serum Addition Effect: In a fixed
    solution nano-Ni,  nano-Ti and KLN all reduced the
    measured IL-6 by 60+ percent. Addition of BSA or
    bovine serum dose dependently reduced the action
    of the  particles to near control levels.
    
    PM Effects (without added protein) on IL-6 In
    Solution: Increasing metal concentration did not
    affect  a fixed  IL-6 concentration until the 100 or 316
    pg/mL levels.
    December 2009
                                                   D-73
    

    -------
           Study
                Pollutant
                                                                           Exposure
                                                               Effects
    Reference: Veranth et
    al. (2007, 0903461
    
    Species: Human,
    mouse, rat
    
    Cell Type: A549,
    BEAS-2B (types E and
    U), RAW 264.7,
    Primary macrophages
    S: desert dust (collected from unpaved
    desert road in Utah, PM25 enriched)
    
    V: vanadium soluble (prepared from
    VOS04, Alfa Aesar, Ward Hill, MA)
    
    C: Coal fly ash (PM2 5 enriched and
    derived from commercial power plant
    burning Utah bituminous coal)
    
    D: Diesel PM (tail-pipe particles
    collected from high emitting BSr on-
    road light duty truck)
    
    L: Lipopolysaccharide
    
    T: Titanium dioxide (Alfa Aesar)
    
    K: Kaolin (purchased from Capitol
    Ceramics,  UT)
    
    Particle Size: BET surface (m2/g)
    
    S: 6.2 (PM25 enriched)
    
    V:NA
    
    C: 5.4 (PM2.5 enriched)
    
    D:NR
    
    LIMA
    
    T: 3.5 (1-2  pm)
    
    K: 24 (<200 mesh = 74  \im)
                                                             Route: Cell Culture
    
                                                             Dose/Concentrations: Maximum
                                                             concentrations:
    
                                                             S= 100|jg/cm2
    
                                                             V = 100 pg/cm2
    
                                                             C=100|jg/cm2
    
                                                             D = 32 pg/cm2
    
                                                             L=1000EU/mL
    
                                                             T = 100 pg/cm2
    
                                                             K= 100|jg/cm2
    
                                                             Time to Analysis: 24 h
                                            Viability: Generally, cell viability was greater than
                                            75% of the control post treatment. Vanadium, at the
                                            highest concentration, induced less than 50% of
                                            control viability whereas kaolin,  also at the highest
                                            concentration, induced cell death.
    
                                            IL-6: BEAS-2B E or U in LHC-9 showed a response
                                            to S and L. BEAS-2B (U) was in LHC-9 medium with
                                            added serum (FBS). This resulted in a doubling of
                                            response coupled with at least an 8 fold increase in
                                            control levels. BEAS-2B (E) showed response for S
                                            and V but not L. A549 showed response to S and K.
                                            RAW 264.7 and Rat macrophages showed
                                            responses to Sfvery low) and L. In general, the IL-6
                                            responses in A549 and RAW 264.7 were similar and
                                            significantly lower than the responses in rat
                                            macrophages or BEAS-2B.
    
                                            Effect of Culture Media Composition (BEAS-2B):
                                            Varying ratios of LHC-9 and KGM media resulted in
                                            a near 10 fold increase in control rate once LHC was
                                            33% or more of the media. Upon Soil Dust (NOS)
                                            exposure IL-6 increased linearly with % LHC-9 in
                                            culture/exposure  media. Addition of calf serum (0.1-
                                            10 %) raised control IL-6 levels  at least 40 fold. At a
                                            steady PM concentration, the addition of serum
                                            resulted in a log-linear increase in IL-6 release which
                                            blocked any PM effect.
    
                                            Reversibility of Media Effect:  Changing  media with
                                            every passage showed that media effects do not
                                            persist once media are changed.
    
                                            Culture Well Size: Going from a 6 well to 96 well
                                            plate (decreasing well size) increased IL-6 control
                                            values about ten fold, while the  positive control
                                            (TNF) response increased 3 fold. Hence the
                                            sensitivity of the test (i.e., positive/control response)
                                            declined from 11 fold to 3 fold with increasing well
                                            number / decreasing well size. Because cell seeding
                                            density and the like were held constant, these
                                            changes suggest that edge effects are the cause of
                                            the IL-6 changes.
    Reference: Veranth et  PM2.s samples from 28 samples from 8
                         locations in Utah, New Mexico and
                         Texas (rural, industrial, road side,
                         military)
    al. (2006, 0874791
    
    Species: Human
    
    Cell Type: BEAS-2B
                         2 coal fly ash samples (a product of
                         combustion using Utah bituminous coal
                         and New Mexico bituminous coal)
    
                         Ti02
    
                         kaolin clay
    
                         Particle Size: PM25; Ti02:1-2 pm
    Route: Cell Culture (35,000 cells/ cm2)
    
    Dose/Concentration: 10, 20, 40, 80 pg/cm2
    
    Time to Analysis: 24 h
                                                                                Cell Assays: In sample soils viability declined dose
                                                                                dependency while IL-6 increased dose-dependently
                                                                                IL-8 was highly variable (peak at 20 pg/l, dose-
                                                                                dependent increase or flat response.)
    
                                                                                IL-6 Assays for All Soil PMs: Soils ranged across
                                                                                an order of magnitude greater than LPS, coal fly
                                                                                ash, Ti02 or kaolin samples. One soil even
                                                                                exceeded the pos V control at equal concentrations
    
                                                                                Correlation with Cell Viability: Correlation was
                                                                                strong for Mn (p<0.001) and weak for ECS, K, Se,
                                                                                andHg(0.01
    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Veranth et  PM25 enriched soil samples
    al. (2004, 0874801     ^ _,    ^ _,  t       _,
                         DD: desert dust, unpaved road, Utah
    Species: Human
    
    Cell Type: BEAS-2B
    WM: West Mesa, sandy grazing site,
    NM
    
    R40: Range 40 gravel soil, TX
    
    UN :Uinta, sandy soil, UT
    
    Particle Size: 0.4-3 pm
    Route: Cell Culture (20,000/crri)
    
    Dose/Concentration: 10, 20, 40, 80,160
    pg/cm2
    
    Time to Analysis: 24 h
    Elemental Analysis of PM: Major differences UN
    generally lower in major minerals but high Fe
    content and high EC. High Mn. Low Pb and Zn
    
    Cytotoxicity: UN and WM were the most cytotoxic
    at all dose levels, followed by R40 and DD. All
    particles showed a dose-dependent cytotoxic
    response.
    
    IL-6 Release: DD and R40 (up to the 160 pg/cm2)
    showed dose-dependent responses and induced an
    8-fold increase at the highest concentration levels.
    WM peaked at 40 pg/cm2 and UN induced similar
    responses above 10 pg/cm2.
    
    IL- 8 Release: DD induced a dose-dependent
    response. WM peaked at 10 pg/cm2. Release
    induced by DD and WM seemed to be limited by
    toxicity There was no treatment with R40.
    
    TNF-a: DD, WM and UN induced release was not
    detected at the 40 or 80 pg/cm2 concentrations.
    
    IPS: IPS was the primary factor in inducing IL-6
    release when exposed to LPS-containing  mixtures.
    LPS alone induced lesser responses than treatment
    to the environmental dust particles. TiLPS induced a
    less than  two-fold increase in IL-6 versus the over
    seven-fold increase induced by soil dust positive
    control. LPS treatments were less cytotoxic than DD.
    Limited IL-6 and IL-8 responses were observed  at
    2000 EU/mL compared with DD at 80 pg/cm
    
    Endotoxin: Inverse relationship between  endotoxin
    content and IL-6 release was observed.
    
    Viability vs Physical Modification of Dust Sample
    (no UN):  Only leaching in a variety of water based
    vehicles increased viability minimally (generally  <25
    %). Heat treatment (150-, 300, 550° F) and
    methanol extraction had no effect
    
    IL-6 Release vs Physical Modification of Dust
    Sample (no UN): One hour thermal treatment at
    150°  F had no effect on IL-6 response. All other
    treatments reduced IL-6 release (heat 350°, 500°
    and extractions).
    Reference: Veronesi
    et al. (2002, 0245991
    
    Species: Human
    
    Cell Type: BEAS-2B
    Ambient PM
    
    - St. Louis: Urban particulates
    
    - Ottawa: Urban particulates
    
    -MSH: Volcanic dust from Washington
    state's Mt. St. Helen
    
    -Woodstove: Woodstove particles from
    conventional fireplace burner
    
    -CFA: Coal fly ash from western U.S.
    power plant
    
    -OFA: Oil fly ash from Niagara, NY
    
    -A: Total Fractions
    
    - B: Soluble Fractions
    
    - C: Washed Fractions
    
    Particle Size: PM >2.5 pm; PM: 2-10
    pm; PM >10 pm
    Route: Cell Culture
    
    Dose/Concentration: 50 pg/mL; 30 pg/cm2
    
    100pg/mL; 60 pg/cm2
    
    Time to Analysis: 4,16 h
    Ca: Calcium increased significantly with all particles
    types.
    
    IL-6: At 50 and 100 pg/mL, IL-6 increased with all
    particle types at 4 and 16 h. Overall, fraction -A was
    the most potent.
    
    Surface charge: Surface charge correlated strongly
    with increases in both Ca2* and IL-6 levels. OFA,
    however, was unmeasurable due to technical
    difficulties.
    December 2009
                                                    D-75
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Vogel et
    al. (2005, 0878911
    
    Species: Human
    
    Cell Type: U937
     ATCC) monocytes
     macrophage
    differentiation)
    UDP:SRM 1649 (MIST)
    
    UDP-OE: DCM extract of SRM-1649,
    0.45 pm filter
    
    sUDP: stripped particles UDP
    
    DEP: SRM 2975 (NIST)
    
    DEP-OE: DCM extract of SRM-2975,
    0.45 pm filter
    
    sDEP: stripped particles DEP
    
    CB95: Carbon Black (Degussa)
    
    Particle Size: UDP, DEP: NR;
    CB95: 95 nm
    Route: Cell Culture (2x10b - 2x10b cells/ml)
    
    Dose/Concentration: DEP, UDP: 2.5,10 or
    40 pg/cm2
    
    (eq to 12.5, 40, 200|jg/mL)
    
    DEP-OE, UDP- OE: 10 pg/cm2 (particle
    equivalent)
    
    Time to Analysis: 24 h
    Effect On mRNA Expression (COX-2, TNF-o, IL-6,
    IL-8, C/EBPp, CRP, CYP1a1): All DEP and UDP
    induced dose-dependent increases. IL-6 tended to
    plateau at 10 pg/cm .  Generally, with the exception
    of COX-2, UDP effects on genes were stronger than
    DEP.
    
    Cytotoxicity: Both DEP and UDP were cytotoxic at
    40 pg/cm2
    
    Fractionation and mRNA Expression: For COX-2,
    TNF-a, IL-8 mRNA fractions were much more active
    than parent particles and consequently stripped
    particles were much less active than parent
    particles. CB95 had no effect. The reverse effect
    occurred for IL-6 and  CRP mRNA expression. The
    particles that induced mRNA expression in
    decreasing order are: sUDP, UDP, UDP-OE.
    
    Inhibition Of mRNA  Expression: CRP:
    pretreatment with IgG and wortmannin (Fey receptor
    binding and ingestion dependent inhibitors resp)
    blocked the effects of DEP,  UDP and sDEP and
    sUDP Luteolin (AhR inhibitor) had no effect.
    
    COX-2: Only luteolin inhibited COX-2 expression for
    DEP, DEP-OE, UDP, and UDP-OE.
    
    CYP1a1: Luteolin also inhibited OE-DEP and OE-
    DUP effects (only those two particles tested).
    
    Cholesterol Accumulation: DEP, UDP and UDP-
    OE and DEP-OE at 10 pg/cm2 all increased
    cholesterol accumulation by at least 2 fold
    Reference: Wang et
    al. (2003, 1571061
    
    Species: Rat
    
    Cell Type: Lung
    Myofibroblasts
    V205: (Aldrich Chemical Co.,
    Wisconsin)
    
    Particle Size: NR
    Route: Cell Culture (1 xio5 cells/100 mm
    dish; 3.2x104 cells/cm2)
    
    Dose/Concentration: 400 |jm
    
    Time to Analysis: 0.5,1,4, 24 h
    H202 Drives STAT-1 Activation: Pretreatment with
    NAC or catalase reduced V205-induced STAT
    activation by more than 90% and completely
    abolished H202-induced STAT activation. Within 5
    min of V20s treatment, H202 was significantly
    decreased in the supernatants of cultured
    myofibroblasts and suppression of H202 levels
    continued for up to 24 h post V205 treatment. This
    supports the findings that myofibroblast-generated
    H202 is required for V205-induced STAT activation.
    
    Temporal STAT-1 Activation: H202 induced rapid
    activation within minutes whereas activation by V205
    occurred more slowly (beginning 8h post treatment).
    
    p38, ERK, EGFR: p38 and EGFR are required for
    H202- or VA-induced STAT-1 activation whereas
    ERK is not required
    Reference: Whitekus
    et al. (2002, 1571421
    
    Species: Mouse
    
    Cell Line: RAW264.7
    DEP (light-duty, four-cylinder engine-
    4JB1 type, Isuzu Automobile, Japan;
    standard diesel fuel) (extracts)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 50 pg/mL
    
    Time to Analysis: 5 h
    DEP significantly reduced the GSH:GSSG ratio. This
    effect was prevented by adding thiol antioxidants
    NAC or BUG. DEP increased  lipid peroxide levels,
    but the addition of all antioxidants decreased these
    levels. DEP increased carbonyl groups. NAC, BUG,
    and luteolin reduced HO-1 expression.
    December  2009
                                                   D-76
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Wilson et  CB: Carbon Black, Printex 90
    al. (2007, 0972681     (Degussa)
    Species: Mouse
    
    Cell Type: J774
    FeCI3
    
    ZnCI2
    
    Particle Size: CB: 14nm
    Route: Cell Culture (4x1 Ob cells/ml at
    1 ml/well)
    
    Dose/Concentration: CB 1.9 -31 pg/mL;
    FeCI3,ZnCI2 0.01-100 pmol
    
    Time to Analysis: 4 h
    ROS Production in Cells: CB alone increased
    ROS. Coexposure with ZnCI2 did not affect ROS.
    
    ROS Production - Cell Free: CB induced a
    significant increase in ROS. ZnCI2 had no effect.
    Coexposure CB/Zn also had no effect.
    
    TNF-o Production (Fe -In 0.01-100 umol):
    Coexposure of CB over a range of metals gave no
    change over CB alone for Fe. For Zn, only at the
    concentration of 100  pmol was there a small
    interaction between Zn and CB.
    
    Similar results were seen at metal concentrations
    between 20 -100 pmol. Synergism was observed
    between Zn and CB and no observed effect of Fe.
    
    Macrophage Cytoskeleton: CB resulted in black
    vacuoles. Co-treatment of cells with Zn and CB
    increased the severity of Zn effects.  Fe exhibited no
    synergism.
    
    Apoptosis /Necrosis: No synergism of CB with
    either Fe or Zn.
    
    Phagocytosis: Only at 31  pmol CB and 50 pmol Zn
    did a synergistic effect occur; it resulted in a 4-fold
    reduction.
    Reference: Wottrich et Fe: hematite a-Fe203
    al. (2004, 0945181
                         Si60: silicasol (Si02, amorphous silica)
    Species: Human
                         SMOO: silicasol
    Cell Type: A549, THP-
    1, Mono Mac 6        Q: crystalline quartz DQ12
    
                         Particle Size: Fe: 50-90 nm; Si60: 60
                         nm; SMOO: 80-110 nm;Q<5|jm
                                        Route: Cell Culture (2x104 cells/well. Co-
                                        culture: 2x104A549 and 2x103
                                        Macrophages)
    
                                        Dose/Concentration: A549 light
                                        microscopy hematite 100|jg/mL (23 pg/cm2)
    
                                        TEM hematite 50 pg/mL (16 pg/cm2)
    
                                        Cytotoxicity 10,  50,100 and 200 pg/mL (6.1,
                                        30, 61 and 121  pg/cm2)
    
                                        Cytokines 50 and 200 pg/mL
    
                                        Time to Analysis:  24 h
                                            Particle Uptake: Hematite agglomeration was
                                            observed in all 3 cell lines. TEM confirmed cytosol
                                            aggregates as well as single particles, which
                                            includes particles transported intracellularly to
                                            basolateral membrane of epithelial cells.
    
                                            Cytotoxicity: LDH increased significantly in A549.
                                            In decreasing order, Q, Fe, S60, and S100 (which
                                            exhibited levels similar to controls) all induced
                                            Cytotoxicity. THP-1  cells appeared the most sensitive
                                            with Q, Fe, S60, S100, control inducing Cytotoxicity
                                            in decreasing order. Mono Mac 6 cells were the least
                                            sensitive with Fe, S60, Q, S100.
    
                                            Cytokines: IL-6 and IL-8 released from A549 cells
                                            upon exposure to all particles. No response was
                                            observed in Mono Mac 6 or in THP-1  cells.
    
                                            Co-cultures: Mix of A549 with either  Mono Mac 6 or
                                            THP-1 led to a large (ten fold) increase  in response
                                            to particles. Ten fold increases were observed in IL-6
                                            and IL-8 levels with the Mono Mac 6 co-culture and
                                            the THP-1 co-culture,  respectively.
    December 2009
                                                    D-77
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Wu et al.
    (2007, 0984121
    
    Species: Human
    
    Cell Line: B82L
    
    Cell Type: B82L- par
    (parental fibroblasts),
    B82L-wt (wild type
    EGFR),  B82L-K721M
    (kinase defective
    EGFR),  B82L-c'958
    (COOH-terminally
    truncated EGFR at
    Tyr-958)
    ZnS04 (Sigma)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: Zn: 500 pmol
    
    EGF:100ng/mL
    
    Time to Analysis: 20 min
    EGFR Mutations: EGFR-wt has a
    functional tyrosine kinase domain, intact Src
    phosphorylation (Tyr 845) and 5 tyrosine
    autophosphorylation sites. EGFR-c'958 lacks all 5
    tyrosine autophosphorylation sites. EGFR-
    K721M lacks tyrosine kinase (ATP binding). EGFR-
    Y845F lacks Src autophosphorylation (Tyr 845) and,
    instead, has a receptor at Tyr 845 that is
    phosphorylated by nonreceptor Tyrosine kinase Src.
    
    Zn Induced Ras (MARK signaling protein): No
    effect was observed in B82L-par cells. Zn  had an
    effect in -wt, -c'958,  and -K721M which confirms the
    need for EGFR. This indicates that neither tyrosine
    kinase nor autophosphorylation sites were required
    for Zn effects. No observed increase for Y845F
    indicated that EGFR tyrosine 845 (phosphorylated
    by c-Src) is  required for Zn effects. However,  it was
    not required for EGF effects.
    
    Src Kinase Requirement: Using a Src blocker
    drastically reduced Zn effect but not the EGF effect.
    Src activation occurred independent of EGFR Tyr-
    845.
    
    Zn Induced Association of EGFR with Src: Zn
    induced a physical association in all 4 mutants; EGF
    did not.
    
    Zn Induced Phosphorylation of EGFR at Tyr-846:
    Zn induced  phosporylation of EGFR at Tyr-845 in
    B82L-wt,-c'958 and  -K721 M.  EGF exhibited similar
    effects. Src  blockers significantly reduced
    phosphorylation induced byZn but not for EGF.
    Neither Zn or EGF induced phosphorylation in B82L-
    Y845F cells.
    Reference: Wu et al.
    (2003, 1997491
    
    Species: Human
    
    Cell Type: BEAS-2B
    Zinc Ion: Zn *
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 10, 25, 50 pmol
    
    Time to Analysis: 0-8 h
    Cytotoxicity: Exposure to 50 pmol Zn2* for 8 h did
    not result in significant alterations in cell viability.
    
    PTEN Protein Levels:  50 pmol Zn2* for 4 and 8 h
    significantly decreased  levels in a dose-dependent
    manner. Exposure to 50 pM vanadyl sulfate
    (tyrosine phosphatase inhibitor) had minimal effects
    on PTEN. 100 ng/mL of non-specified EGF receptor
    ligand for 1-8 h did not exhibit any significant effects
    on PTEN levels.
    
    P13K/Akt: Zinc induced Akt activation in a dose-
    and time- dependent fashion. Active Akt levels were
    the highest at 1 h post exposure to Zn2*,
    corresponding with the time period when there was
    a minimal effect on PTEN protein  level. When
    treated with LY294002 (inhibitor of P13K activity),
    Akt phosphorylation was significantly inhibited.
    
    PTEN mRNA Levels: Decreased PTEN  mRNA
    expression was observed in cells  exposed to 50
    pmol Zn2* for 8 h whereas PTEN protein  levels
    declined as early as 4 h.
    
    Proteasome-mediated PTEN Degradation: Use of
    MG132 (proteasome inhibitor) had no significant
    effect on Zn2* induced PTEN mRNA expression.
    Therefore mRNA expression may not play a critical
    role in PTEN protein reduction. Instead data
    suggested that 26 S proteasome played a vital role
    in Zn2* induced PTEN degradation. PI3K inhibitor
    blocked Zn-induced PTEN degradation, but failed  to
    prevent significant Zn-induced down-regulation of
    PTEN mRNA.
    December 2009
                                                    D-78
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Wu et al.
    (2004, 0969491
    
    Species: Human
    
    Cell Type: NHBE
    Zinc Ion: Zn *
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 100 pmol
    
    Time to Analysis: 2 h
    Cell Viability: After 2 h of exposure, Zn * induced
    effects in NHBE cells at 100 and 200 pmol levels
    (but not 50 pmol). Continuing exposure to 100 pmol
    Zn * for 4 and 6 h did not significantly alter cell
    viability. Thus, in all subsequent studies, NHBE cells
    were treated with 100 pmol Zn2*.
    
    Induced EGFR Phosphorylation: Exposure to
    100pM Zn2* for 1-4 h induced phosphorylation of
    EGFR in NHBE cells. EGFR kinase inhibitor
    PD153035 (to determine if phosphorylation of EGFR
    was the result of autophosphorylation of activated
    EGFR tyrosine kinase activity) caused Zn * -induced
    phosphorylation to subside. Zn2* activity requires
    tyrosine kinase activity.
    
    EGFR Phosphorylation Pathway: To test whether
    Zn * exposure results in ligand release, which in turn
    can activate phosphorylation, NHBE cells were
    pretreated with LA1 blocking antibody Results
    showed significant suppression of Zn * induced
    phosphorylation, therefore Zn2* phosphorylation
    might be initiated by the release of EGFR ligands.
    
    HB-EGF, TGF-a, EOF: To examine the involvement
    of specific ligands (HB-EGF. TGF-a and EGF) in the
    phosphorylation pathway,  cells were exposed to
    anti-HB-EGF, anti-TGF-a and anti-EGF. Results
    showed that anti-HB-EGF reduced Zn2* induced
    phosphorylation significantly, anti-TGF-a produced
    partial inhibition and anti-EGF had no inhibitory
    effect. Exposure with blocking antibody LA1 was
    tested to determine if it caused an increase in
    soluble HB-EGF. HB-EGF mRNA expression was
    also elevated in cells exposed to Zn . Previous
    studies indicate metalloproteinase (MMP)
    involvement in cleaving ligand precursors. It was
    found that MMP-3 inhibitor partially blocks Zn2*
    induced HB-EGF release. (MMP-2 and MMP-9 did
    not show similar inhibition patterns) Zn2* exposure
    increased the release of MMP-3 from HNBE cells.
    December 2009
                                                    D-79
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Wu et al.
    (2005, 0973501
    
    Species: Human
    
    Cell Line: Subclone
    S6
    
    Cell Type: BEAS-2B
    Zinc Ion: Zn *
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 50 pmol
    
    Time to Analysis: 4 or 8 h; EGFR
    phosphorylation: 30, 60,120, 240 min
    Cell Viability: Exposure to 50 pmol Zn * for 8 h did
    not result in significant alterations in cell viability
    (assessed by LDH release).
    
    P13K/AM Signaling Pathway: To evaluate P13K's
    on COX-2 Zn  induced expression, LY-294002 (a
    P13 inhibitor) and another unnamed P13 inhibitor
    were used. Exposed cells indicated suppressed
    levels of Zn2* induced COX-2. To determine Akt role,
    ad-DN-Akt (AAA) was used. Infected cells indicated
    over-expression of Akt and significant reduction of
    Zn2* induced GSK-3o/|3 phosphorylation. Over
    expression of DN-Akt(AAA) blocked Zn2* induced
    COX-2 expression.
    
    PTEN's Role in Blocking Zn2+ Induced COX-2
    mRNA Expression: PTEN is an antagonist of
    P13/AM pathway. Overexpression of wildtype PTEN
    blocked Zn2*-induced mRNA COX-2 expression,
    suggesting PTEN inhibits PIPS signal transduction to
    Akt.
    
    Analysis of the Src/EGFR Signaling Pathway:
    Zn2* induced a time-dependent increase in Src and
    EGFR phosphorylation in cells. Blockage of Src
    activity via PP2 (Src inhibitor) decreased Zn2*
    induced EGFR phosphorylation. The EGFR tyrosine
    inhibitor completely blocked Zn2*-induced EGFR
    phosphorylation. EGF (a ligand of EGFR signaling)
    induced COX-2 expression, suggesting that EGFR
    regulated Zn2* -induced COX-2 expression.
    
    p-38 and EGFR Kinase Activity: Use of PD-
    153035 (EGFR inhibitor) and PP2 (Src inhibitor) and
    SB-203580 (p38 inhibitor) all blocked Zn2*-induced
    Akt phosphorylation of Src., EGFR and p38. It is
    thought that p38 is a critical kinase in regulation of
    Zn *-induced COX-2 protein expression.
    Reference: Yacobi et
    al. (2007, 1561661
    
    Species: Rat
    
    Cell Type: L2 (Lung
    epithelial cells)
    PNP: Polystyrene nanoparticles,
    negatively charged (Molecular Probes,
    Eugene, OR)
    
    PNPA:Amidine modified PNP,
    positively charged
    
    SWCNT: Single-wall carbon nanotubes
    (Carbon Nanotech, Houston, TX)
    
    QDC: Chitosan coated (CdSe/ZnS)
    Quantum dots, positively charged
    (made)
    
    QDA: Alginate coated QD, negatively
    charged
    
    UAPS:  Ultrafme Ambient particulate
    suspensions (VACES) (48 % OC)
    
    Particle Size: PNP20: 20 nm;
    PNP100:100 pm; SWCNT: 0.8-1.2 nm
    (diameter); SWCNT: 100-1000 nm;
    QD:30nm;UAPS:<150nm
    Route: Cell Culture (1.2x106 cells/cm2)
    
    Dose/Concentration: PNP up to 706 pg/mL
    
    QDupto176|jg/mL
    
    SWCNT up to 88 pg/ ml
    
    UAPS up to 36 pg/mL
    
    Time to Analysis: on days 4, 5 or 6 by
    replacing monolayer apical fluid with PM in
    suspension for up to 1440 min.
    
    Intermediate measurements at 15, 30, 60,
    120, 240 and 1440 min.
    UAPS and Rt (transmonolayer resistance): Rt
    declined up to 60% within 1 h at 36 pg/mL Rt
    plateaued (or exhibited a very slight upgradient) for
    up to 24 h (last measurement). No cytotoxicity was
    observed. Replacement of apical fluid with fresh
    media after 2 h of exposure restored Rt to near
    control values within 24 h.
    
    UAPS and Leq (short-circuit current): Peak
    decline of 30% after 4 h followed by gradual
    recovery over 24 h. Replacing media after 2 h
    exposure returned leq to control values within 24 h.
    
    UAPS and Apparent Permeability: Permeability
    measured via C14 mannitol and inulin showed no
    effect of UAPS.
    
    QD and Rt: QD depressed Rt by nearly 55% at 4 h
    for positively charged and 30% for negatively
    charged QDs. Recovery towards control values
    started at 4 h and was near complete at 24 h
    
    SWCNT and Rt: SWCNT depressed Rt by ~ 40% at
    1 h (same for 22, 44, and 88 pg/mL). Recovery was
    near complete at 4 h and complete at 24 h.
    
    PNP and Rt: No statistically significant effects were
    observed.
    December  2009
                                                   D-80
    

    -------
           Study
                Pollutant
                  Exposure
                       Effects
    Reference: Yun et al.   DEP: Collected using a 6 cyl 11L,       Route: Cell Culture (3x104 cells/well)
    (2005, 0883021        heavy duty (2001 yr) bus engine (South
    v	Korea)                             Dose/Concentration: 1,10,100,250,500
    Species: Human                                          and 1000 pg/mL; main testing 250 pg/mL
                         Particle Size: NR
    Cell Type:  A549                                          Time to Analysis: 12 h
                                                                              NF-KB Transcription Activation: DEP induced
                                                                              dose-dependent activity up to 250 pg/mL After
                                                                              peaking at 250 pg/mL, concentrations above 250
                                                                              induced dose- dependent declines. Activity peaked
                                                                              at 12 h for 250 pg/mL and declined to control at 24
                                                                              or 48 h. The mechanism of DEP action was the
                                                                              degradation of iKBa which is an intracellular inhibitor
                                                                              of nuclear translocation of NF-KB.
    
                                                                              TAK1  and NIK Required for NF-KB Activation by
                                                                              DEP:  Dominant negative mutants of TAK1 and NIK
                                                                              reduced DEP induced response to basal level. TAK1
                                                                              was phosphorylated after DEP exposure and was
                                                                              sustained for at least 90 min.
    Reference: Zhang et
    al. (2007, 1561791
    PM25: Collected by baghouse from
    Dusseldorf, Germany
    Species: Human, Rat   Particle Characterization: Carbon 20%,
    ~,,T     Ac.nn, ^   Hydrogen 1.4%, Nitrogen <0.5%,
    Cell Type:  A549, RLE-  oxygen 14.1%, Sulfur 2.1%, Ash
    6TN                  63*2%.
    
                         Particle Size: PM25
    Route: Cell Culture
    
    Dose/Concentration: 100 |jg/cm;
    
    Time to Analysis: 24 h
    Apoptosis: At 100 pg/mL for 24 h, PM induced a
    2.5 fold increase in apoptosis in A549.
    
    Mitochondria! Membrane Potential: A significant
    reduction in AEC mitochondrial membrane potential
    was observed.
    
    Caspase -3 & -9: Increased  activity of both
    enzymes in both cell types was observed. More
    specifically, a 2- to 2.5-fold increase of caspase -3
    and -9 in A549 and an 8-fold increase of caspase-9
    and 4-fold increase of caspase-3 in RLE-6TN were
    observed.
    
    BIM: Downregulation of BIM by RNA interference
    inhibited PM-induced apoptosis. An inhibited
    decrease in mitochondrial membrane potential and
    activation of both caspases were observed.
    Reference: Zhang et
    al. (2004, 1571831
    
    Species: Mice
    
    Cell Line/Type: C10
    (alveolar Type I Hike
    epithelial cell line)
    DEP: SRM 1650a
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 5 or 25 pg/mL
    
    Time to Analysis: 30-360 min
    fra Expression: DEP induces fra-1 but not fra-2
    expression. mRNA induction peaks around 180 min
    DEP affects fra-1 mRNA expression at the
    transcriptional level.
    
    ERK/JNK/p38 MARK signaling pathways: 3
    inhibitors (PD-98059, SB-202190 or SP-600125) all
    reduced DEP stimulated fra-1 induction to near
    control levels. DEP stimulated phosphorylation of
    the MAPKs which peaks at 60 min but stays
    elevated at 180 min.
    
    MMP-9 promoter activity: fra-1 upregulation may
    play a role in DEP induced increases in MMP-9
    promoter activity as fra-1 appears to bind at the -79
    TRE sequence of the MMP-9 promoter.
    Table D-3.      Respiratory effects:  in vivo studies.
    Reference
    Reference:
    Adamson et al.
    (2003, 0879431
    Species: Rat
    uGndGT! M3l6
    Strain: SD
    Weight: 150g
    
    
    
    
    Pollutant
    PM,0: EHC-93W (whole dust)
    EHC-93S (soluble)
    EHC-93L (leached)
    EHC-2KW, -S, -L
    Measured components Zn, Mg,
    Pb, Fe, Cu, Al
    Particle Size: EHC-93VV -93S, -
    93L, -2KW, -2KS, -2KL: PM,0
    
    
    
    
    Exposure
    Route: IT Instillation
    Dose/Concentration: 5 mg/rat; 33.3 mg/kg
    Time to Analysis: 4 h, 1 day, 3 day, 7 days, 14
    days
    
    
    
    
    
    
    
    Effects
    BALF Cells: The greatest increase in cell numbers
    was observed with EHC-93W Activity peaked at 1 day
    with a return to normal levels by 7 days. EHC-93L also
    induced an increase in cell numbers, more so than
    EHC-93S, but both particles induced statistically
    significant increases. However, these increases were
    mostly attributable to an increase in the AM and PMN
    populations.
    BALF Inflammatory/Injury Markers: Metallo-
    proteinase (MMP) 2 and 9 both increased, peaking at 1
    day and 4 h respectively. MMP2 activity appears
    related to the soluble fraction whereas MMP-9 activity
    appears to be related to the leachable fraction.
    December  2009
                                                   D-81
    

    -------
        Reference
             Pollutant
                                                                     Exposure
                                                                                                                     Effects
    Reference: Ahn et
    al. (2008, 1561991
    
    
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/C1
    
    Age: 6 wk
    
    Weight: 19-24 g
    DEP: Collected using a turbo-     Route: Oropharyngeal Aspiration
    charged, intercooler, 6-cylinder,
    heavy-duty, diesel engine (model  Dose/Concentration: 1,10, 25 mg/kg per day;
        —                      Those receiving 25 mg/kg DEP also received pre-
                                  treatment of Dex (1, 5 mg/kg) 1 h prior
                       year 2000
    
                       DPBS: control
    
                       Particle Size: NR
                                 Time to Analysis: 5 consecutive days; 72 h post
                                 final exposure
                                                                                                  BALF Inflammatory/Injury Markers: Lung injury was
                                                                                                  more severe in mice exposed to 25 mg/kg of DEP than
                                                                                                  when compared to mice exposed to 1 mg/kg DEP.
                                                                                                  However, lung injury caused by exposure to 25 mg/kg
                                                                                                  DEP could be completely prevented with pre-treatment
                                                                                                  of 5mg/kg Dex. Treatment with 1 mg/kg Dex prior to
                                                                                                  exposure to 25 mg/kg DEP depicted partial reduction in
                                                                                                  lung injury.
    
                                                                                                  BALF Cells: Treatment with DEP over a 5 day period
                                                                                                  caused an increase in total number of cells
                                                                                                  (macrophages, neutrophilsand lymphocytes) when
                                                                                                  compared to control.
                                                                                                  Total Cells: Control - 5.33 ± 0.44 cells
                                                                                                  1 mg/kg DEP-6.26 ±0.87 cells
                                                                                                  10 mg/kg DEP-14.40+ 1.90 cells
                                                                                                  25 mg/kg DEP - 47.20  ± 3.40 cells
    
                                                                                                  COX-2 Expression: Exposure to DEP lead to a dose-
                                                                                                  dependent increase in COX-2 levels; specifically,
                                                                                                  treatment with 25 mg/kg significantly increased COX-2
                                                                                                  levels. This effect was completely reduced by treatment
                                                                                                  with 5mg/kg of Dex.
    Reference: Ahsan   DEP: Obtained from Dr. Masaru   Route: IT Instillation
    et al. (2005,1562001 Sagai (Amori, Japan)
    
                       Particle Size: NR
    Species: Mouse
    
    Gender: Male and
    Female
    
    Strains: hTrx-1-
    transgenic and
    C57BL/6 (control)
    
    Age: 8-8.5 wk
                                                     Dose/Concentration: Lung Damage: 0.1
                                                     mg/mouse; Survival Analysis: 0.2 mg/mouse; ESR:
                                                     0.05 mg/mouse
    
                                                     Time to Analysis: 24 h
                                                                              ESR: hTrx-1 induced 0.05 mg generation of hydroxyl
                                                                              radicals in the lungs (mid thorax ESR spectra)
                                                                              compared to control.
    
                                                                              BAL Inflammatory/Injury Markers: hTrx-1 attenuated
                                                                              cellular damage from 0.1 mg DEP. Control mice showed
                                                                              massive edema with neutrophilic infiltration,
                                                                              hemorrhagic alveolar damage and collapsed air
                                                                              spaces.  hTrx-1 mice showed mild/moderate edema
                                                                              with clear demarcation of air spaces.
    
                                                                              Viability: After 4,12 and 24 h, survival was 32, 24 and
                                                                              12% respectively  as compared to 80, 52 and 40% for
                                                                              hTrx-1 mice.
    Reference: Andre et UFCP: Ultra Fine Carbon
    al. (2006, 0913761    Particles (electric spark
                       generator,  Model GFG 1000;
    Species: Mouse     pa|aS] Karlsruhe, Germany)
    Gender: Female
    
    Strain: BALB/cJ
    
    Age: 10-12 wk
                       Measured Component:
                       UFCP>96% EC
    
                       Particle Size: 49 nm
                                  Route: Whole-body Inhalation
    
                                  Dose/Concentration: 380 |jg/m;
    
                                  Time to Analysis: 4 and 24 h; 0 and 24 h post-
                                  exposure
                                                                                                  BALF Cells: A small increase in PMN number
                                                                                                  suggests a minor inflammatory response after 24 h
                                                                                                  exposure. Number of macrophages did not increase.
    
                                                                                                  BAL Inflammatory/Injury Markers: Total protein
                                                                                                  concentration significantly increased post 24 h
                                                                                                  inhalation. Post 4 h, heat shock proteins were induced.
                                                                                                  Post 24 h, immunomodulatory proteins (osteopontin,
                                                                                                  galectin-3 and lipocalin-2) significantly increased in
                                                                                                  alveolar macrophages and septal cells. 236 (1.9%)
                                                                                                  genes was increased and 307 (2.5%) genes were
                                                                                                  decreased with upregulated genes being primarily
                                                                                                  related to the inflammatory process.
    Reference:
    
    Antonini etal.
    (2004, 0971991
    
    Species: Rats
    
    Gender: Male
    
    Strain: SD
    
    Weight: -250 g
    ROFA-P: Precipitator
    
    -S: Soluble (0.22 pm filter),
    Components: Fe, Al, Ni, Ca, Me
    Zn
    
    -I: insoluble, Components: Fe,
    Al, Ni, Ca, Mg, Zn, V
    
    -T: total
    
    ROFA-AH: Air Heater
    
    -S: Soluble (0.22 pm filter),
    Components: Fe, V, Ni, AL
    -I: Insoluble, Components: Fe,  V,
    Ni.AL
    
    -T: Total
    
    Particle Size: < 3 pm (mean
    diameter)
                                                     Route: IT Instillation
    
                                                     Dose/Concentration: 1mg/100g bw in 300 pi
                                                     saline; 60 mg/kg
    
                                                     Time to Analysis: 24 h; Clearance Experiment:
                                                     two single exposures day 0 and 3 observed at day
                                                     6, 8 and 10
                                                                                                  ESR: Only ROFA-P contained free radicals, primarily in
                                                                                                  ROFA-P-S.
    
                                                                                                  BALF Cells: No effects on alveolar macrophages were
                                                                                                  observed, but all ROFA-P fractions increased lung
                                                                                                  neutrophils. ROFA-P-S and ROFA-P-I effects combined
                                                                                                  roughly equaled ROFA-P-T.
    
                                                                                                  BAL Inflammatory/Injury Markers: ROFA-AH-T and
                                                                                                  ROFA-AH-I increased LDH. ROFA-P and -AH
                                                                                                  increased albumin for T and I fractions.
    
                                                                                                  Pulmonary Clearance (Listeria Monocytogenes):
                                                                                                  ROFA-P-T and ROFA-P-S significantly slowed bacteria
                                                                                                  clearance from lungs. ROFA-AH and ROFA-P-I had no
                                                                                                  effect.
    December 2009
                                                     D-82
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Arimoto
    et al. (2007, 0979731
    Species: Mouse
    
    Strain: ICR
    Gender: Male
    
    Age: 6 wk
    
    Weight: 29-33 g
    
    Reference:
    Bachoual et al.
    (2007, 1556671
    Species: Mouse
    
    Strain: C5B1 7
    Gender: Male
    Age: 7 wk
    
    Weight: 22.3 ±
    073 g
    DEP (collected using a 4JB1 4-
    cyl, 2.74L Isuzu diesel engine)
    DEP-OC: organic chemical
    extracts
    
    IPS
    DL=DEP + LPS
    
    DDL = DEP-OC + IPS
    
    Particle Size: 0.4pm
    PER: PM10
    Paris, France subway
    CB
    Ti02
    DEP
    Particle Size: PER: 79% < 0.5
    pm; 20%: 0.5-1 pm
    PR' qc nm
    WD. y\j MI M
    Tif~l ' 1 ^D i im
    1 1^2' ' ^^ M
    DEP: NR
    Route: IT Instillation
    Dose/Concentration: DEP or DEP-OC: 4 mg/kg;
    LPS:2.5mg/kg;DLorDOL:NR
    
    Time to Analysis: 24 h
    
    
    
    
    
    
    Route: IT Instillation
    Dose/Concentration: 5, 50, 100 pg/mouse, 0.22,
    2.2, 4.5 mg/kg
    
    Time to Analysis: 8 or 24 h
    
    
    
    
    
    Cytokines: DEP-OC or DEP alone did not change
    levels of MIP-1a, MCP-1 orMIP-2. DL induced
    significant increases in MIP-1, MIP-2 and MCP-1.
    IPS: IPS and DDL induced increases in MCP-1
    though the increase induced by DLwas greater. No
    effect on MIP-1a or MIP-2 was observed.
    
    
    
    
    
    BALF Cells: 100 pg RER and 100 pg DEP increased
    total cell count and neutrophil influx after 8 h and
    returned to normal by 24 h. Smaller doses of RER and
    DEP induced no effect. CB induced no effect.
    
    BAL Inflammatory/Injury Markers: 100 pg RER
    increased BALF protein after 8 h. No effect was
    observed after 24 h nor with smaller doses of PM. RER
    significantly increased MMP-12 mRNA level after 8 h
    and HO-1 total lung mRNA content. No effects on
    MMP-2 or -9 or TIMP-1 or -2 expression were
    observed. No effects from CB or DEP were observed.
    f^wtnLinec- 100 I in PPP inrroacoH RAI TMF.rf anH
                                                                                                   MIP-2 protein content after 8 h.
    Reference: Batalha
    et al. (2002, 0881091
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: NR
    
    Weight: 200-250 g
    CAPs (Harvard Ambient Particle
    Concentrator)
    
    Particle Size: Mean: 2.7pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: Range: 73.5-733 pg/m3
    
    Time to Analysis: CAPs exposure 5 h/day, 3 days
    (consecutive). S02 exposure to  induce CB 5 h/day,
    5 days/wk, 6 wk. Killed 24 h postexposure.
    Histopathology: CAPs slightly increased the wall
    thickness of small pulmonary arteries and edema in the
    adventitia and hyperplasia of the terminal bronchiole
    and alveolar ducts epithelium.
    
    L/W ratio: The L/W ratio decreased in CAPs-exposed
    rats as particle mass, Si, Pb, S042-, EC and OC
    increased. Univariate analyses showed  significant
    negative correlations between the L/W ratio and Si and
    S042- in normal rats and Si and  OC in CB rats.
    Multivariate analysis showed only Si to be significant in
    both groups.
    Reference: Becher
    et al. (2007, 0971251
    
    
    Species: Mouse
    
    Strain: Crl/Wky
    (iNOS(-/-)) and
    C57BI/6
    
    Gender: Male
    
    Age: 8-14 wk
    
    Weight: 25 g
    Suspended PM:SRM-1648
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 1.6 pg/lung; 64 mg/kg
    
    Time to Analysis: 20 h
    Cytokines: In both wild and KO strains, all particles
    caused increases of IL-6, MIP-2 and TNF-a levels.
    NADPH-oxidase KO mice showed significantly lower
    levels of IL-6 and MIP-2 responses to SPM compara-
    tively to wildtype. iNOS KO mice showed significantly
    reduced IL-6, TNF-a, MIP-2 responses to SPM
    comparatively to wildtype.
    
    Free Radicals: SPM induced significant increases in
    free radical formation in alveolar type 2 cells but could
    be inhibited by DPI.
    Reference:
    Bhattacharyya et al.
    (2004, 0880951
    
    Species: Mouse
    
    Strain: SD
    
    Weight: 200-250 g
    Douglas Fir Wood Smoke
    (generated by burning wood at
    400°C in crucible oven)
    
    Particle Size: NR
    Route: Nose-only Inhalation
    
    Dose/Concentration: 25 g/mouse
    
    Time to Analysis: Various exposure periods (0, 5,
    1 0,15, 20 min). Parameters measured after 24 h
    recovery period.
    Biochemical Parameters: Lipid peroxidation
    increased after 20 min of wood smoke inhalation as did
    Myeloperoxidase at 20 min. No effects were observed
    at other times or for total antioxidant status, reduced or
    oxidized glutathione.
    
    Antioxidant Enzyme Activities: No effect was
    observed.
    
    Histology: Dose-dependent damage progressing from
    loss of cilia (5 min), degeneration of mucosal
    epithelium, loss of mucosal epithelium to disrupted
    mucosal epithelium with submucosal edema and
    inflammation. Changes persisted for up to 4 days.
    December 2009
                                                      D-83
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Cao et
    al. (2007, 0974911
    
    Species: Rat
    
    Strain: SH and
    WKY
    
    Age: 12 wk
    PM25 (Shanghai, China)
                                                     Route: IT Instillation
    Components: As, Cd, Cr, Cu, Fe,  Dose/Concentration: 1.6, 8.0 and 40 mg/kg
    Ni, Pb, Zn, V, Ba, Se, Mg, Co,
    Mn                            Time to Analysis: Exposed 1/day for 3 days,
                                  sacrificed 24 h following last exposure
    Particle Size: PM2 5
                                                 BALF Cells: PM decreased macrophages and
                                                 increased neutrophils and lymphocytes in a dose-
                                                 dependent manner. For the same exposed dose, WKY
                                                 rats had a higher percentage than SH but a smaller
                                                 percentage of neutrophils and lymphocytes.
    
                                                 BAL Inflammatory/Injury Markers: LDH activity and
                                                 TBARs increased a in dose-dependent manner.
                                                 Notably, activity in  SH rats was much higher than WKY
                                                 at the same dose exposed for each dose level.
    
                                                 Cytokines: PM induced pro-inflammatory cytokine
                                                 release (IL-lp,  TNF-a, CD44,  MIP-2, TLR-4, OPN).
                                                 Again, SH cytokine level was greater than WKY at all
                                                 dose levels. PM induced anti-inflammatory cytokines
                                                 CC16 and HO-1 in a similar manner but at much lower
                                                 rate.
    Reference: Carter
    et al. (2006, 0959361
    
    Species: Rat,
    Mouse, Hamster
    
    Gender: Female
    (all)
    
    Strain: F-344 (rat),
    B6C3F1 (mouse),
    Syrian Golden
    (hamster)
    
    Age:7-10wk
    CB: Printex 90
    
    Particle Size: primary size: 17
    nm; 1.2-1.6pm (aerosol
    aerodynamic diameter)
    Route: Whole-body Inhalation
    
    Dose/Concentration: 1, 7, 50 mg/m3
    
    Time to Analysis: 6 h/day for 5 days/wk for 13 wk;
    1 day, 3 m, 11 m post-exposure
    Superoxide: Levels rose in all species at 50 mg dose.
    Hamsters had no increase at 7 and 1 mg doses. Mice
    also increased at 7 mg. Rats significantly increased at
    all dose levels. Rats maintained elevation except for
    the 50 mg dose at 11 mo postexposure; it declined but
    was still higher than control. Mice maintained elevation
    at 50 mg while 7 mg returned to control levels by 3 mo
    postexposure.
    
    HJQf. At 50 mg, increased levels in all species, with the
    highest in rat, were observed. At 7 mg, increased levels
    in rats and mice were initially seen but levels returned
    to baseline by 11  mo. Hamster levels were not
    significant. At 1 mg, no significant changes were
    observed.
    
    NO: Induced similar reactions as H202. Rat response
    continued through the study while mice and hamsters
    returned to baseline by 11 mo postexposure. Rats
    produced significantly higher levels at all times than
    other species.
    
    BALF Cells: CB induced significant increases in
    neutrophils at 7 and 50 mg for all species. Rats had the
    highest and most prolonged PMN response. Mice and
    hamsters had very similar reactions.
    
    Cytokines: TNF-a, MIP-2 and IL-10 increased in a
    dose-dependent manner in rats and mice. Hamsters
    increased for IL-10 only. MIP-2 levels were highest in
    rats. TNF-a level were similar in all three species at 50
    mg, but hamsters started with a markedly higher basal
    level.
    
    Glutathione Peroxidase: Hamsters were the most
    responsive with significant increases at all levels. Rats
    and mice increased at 50mg and continued to increase
    for up to 11 mo. Hamster levels declined with time but
    continued to be higher than control.
    
    Glutathione Reductase: Rats increased only at 50mg
    and remained elevated for up to 11 mo. Mice increased
    at 7 and 50mg and remained  elevated for up to 11 mo.
    Hamsters increased at all levels at 11 mo, but at 50mg,
    levels only increased post 1 day.
    
    Superoxide Dismutase: All species reacted in a dose-
    dependent manner. Rats were the least responsive.
    Rat SOD activity increased over time while rat and
    mouse activity decreased at 50mg.  Data were
    consistent with cytokine data.
    
    Summary: Rats appear to produce proinflammatory
    responses while mice and hamsters produce
    antiinflammatory responses.
    December 2009
                                                      D-84
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Cassee
    et al. (2005, 0879621
    
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    and SH/NHsd
       e:7wkand8-12
    wk
    CAPs: PM25
    
    Netherland suburban, industrial
    and freeway tunnel site
    collections
    
    Wistar rats pre-exposed to 03
    
    S04, N03 and NH4 ions: 54 ± 4%
    suburban, 53 + 7% industrial and
    35 + 5% freeway site cone, of
    total CAPS mass
    
    Particle Size: PM2 5
    (0.15
    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Cho et
    al. (2005, 1563441
    
    Species: Mouse
    
    Gender: Male
    
    Strains: DBA/2J,
    129P3/J, C57BL/6J,
    BALB/cJ, A/J,
    C3H/HeJ,
    C3H/HeOuJ
    
    Age: 6-8 wk
    ROFA: Obtained from Power unit  Route: IT Instillation                            BALF Cells: Significant genetic effects on number of
    4, Boston, MA                                                               macrophages and PMNs after ROFA challenge. For
                                  Dose/Concentration: 6 mg/kg bw (150 pg in 50pl/ PMNS] DBA/2j, C57BL/6J, BALB/cJ, and 129P3/J all
    Absent of LPS                  25 g)                                         induced increases significantly higher than C3H/HeJ.
    
    Particle Size: NR
                                o
    mice, single. 1.5, 3 and 6 h (compare TLR-
    mediated molecular events)
                                                                                  ^  pM     d macrphages ay increased with
                                                                               ^0uJ< .^   {mxeas^^nm^ different from
                                                                               HeJ.
    
                                                                               BAL Inflammatory/Injury Markers: Significant genetic
                                                                               effect on mean total protein concentration was
                                                                               observed. In decreasing order, DBA/2J, 129P3/J and
                                                                               C57BL/6J all induced increases significantly higher
                                                                               than C3H/HeJ.
    
                                                                               TLR4 mRNA Expression: A significant decrease was
                                                                               observed in TLR4 transcript level in HeJ- ROFA
                                                                               exposed mice post 1 .5 h. Post 6 h, TLR4 levels were
                                                                               greater than the control levels. OuJ expression
                                                                               increased beginning 1.5 h post exposure.
    
                                                                               TLR4 Protein Level: Protein level of OuJ mice
                                                                               significantly exceeded (~2-3 fold) HeJ mice at 1.5, 3
                                                                               and 6 h.
    
                                                                               Activation of Downstream Signal Molecules:
                                                                               Greater activation of MYD88, TRAF6, IRAK-1, NF-KB,
                                                                               MAPK, and AP-1 was observed in OuJ mice than in
                                                                               HeJ mice before the development of ROFA- induced
                                                                               pulmonary injury.
    
                                                                               Cytokines: IL-lp, LT-p,  IL-1a, IL-7, IL-13, IL-16
                                                                               increased in both strains (OuJ and HeJ). Levels of all
                                                                               cytokines above were significantly higher in OuJ than  in
                                                                               HeJ.
    Reference: Churg et
    al. (2003, 0878991
    
    Species: Human
    
    Gender: Female
    (Mexico City); Male,
    Female (Vancouver)
    
    Age: 66 + 9yr
    (Mexico City); 76 +
    11yr (Vancouver)
    
    Weight: NR
    PM (Mexico City-high PM
    region, Vancouver- low PM
    region)
    
    Particle Size: Geometric mean
    size of individual particles in
    tissue: 0.040-0.067 pm;
    Aggregates in tissue: 0.34-0.54
    pm; Mexico City: 2.5,10 pm
    Route: Ambient Air Exposure. Autopsy Tissue.
    
    Dose/Concentration: 10 - >1000x106 g dry
    tissue;  Mexico City: PM10: 66 pg/m3, Vancouver:
    PMi0:25|jg, PM25:15 pg
    
    Time to Analysis: Lung samples taken from
    deceased lifelong Mexico City residents and
    Vancouver residents >20 yr. Subjects were never-
    smokers, did not work in dust occupations or cook
    with biomass fuels.
    The lungs from Mexico City residents showed
    increased muscle and fibrous tissue in the
    membranous bronchioles and respiratory bronchioles
    compared to the Vancouver residents. Pigmented dust,
    lumental distortion and carbonaceous aggregates of
    UFPs were present in the Mexico City lungs.
    Reference: Costa et
    al. (2006, 0884381
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 60 day
    ROFA
    FPSLplant#6oil, 1% sulfur
    
    Particle Size: ~1.95pm
    Route: IT Instillation, Nose-only Inhalation (IH)
    
    Dose/Concentration: IT instillation = 110 pg/rat
    
    IH = 12mg/m3
    
    Time to Analysis: IT instillation: single; IH:6h
    
    24, 48, 96 h (histopathology 24 and 48 only)
    ROFA distribution: IH and IT instillation resulted in
    equivocal distribution (pg/g lung tissue) in 5 different
    lung lobes.
    
    Airway Hyperactivity: IT instillation resulted in
    doubled airway hyperreactivity at 24 h which was
    sustained for 96 h. IH hyperreactivity did not reach
    statistically significant level.
    
    BALF Cells: Neutrophils peaked at 24 h and slowly
    declined at 48 and 96 h.
    
    BAL Inflammatory/Injury Markers: IH and IT
    instillation showed very similar responses (R2  = 0.98).
    Time-dependent increases were observed for protein
    and LDH.
    
    Lung Pathology: IT instillation showed more  alveolitis,
    bronchial inflammatory and fibrinous fluid infiltrate. IH
    showed  relatively more congestion of small airways
    and alveolar hemorrhage.
    December 2009
                                                      D-86
    

    -------
    Reference
    Reference: Courtois
    et al. (2008, 1563691
    Species: Rat
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 12-14 wk
    \A/AiMkti MD
    weight: NK
    Reference: Dick et
    al. (2003, 0366051
    Species: Mouse
    Gender: Female
    Strain: CD1
    Age:8-10wk
    
    Weight: 20-25 g
    
    
    
    Pollutant
    PM(SRM1648;63%inOC, 4-
    7% OC, >1% mass fraction- Si,
    S, Al, Fe, K, Na)
    
    Carbon black (FVV P60)
    UF, fine Ti02
    
    Particle Size: PM mean
    diameter: 0.4 pm; Carbon black:
    FW-13nm, P60-21 nm;Ti02
    mean diameter: 0.1 4pm
    CO: PM Coarse
    Fl: PM Fine
    FU: PM ultrafine
    PM collected in RTP, NC
    Particle Size: CO: 3.5-20 pm;
    FI:1.7-3.5|jm;FU:<17|jm
    
    
    
    
    
    
    Exposure
    Route: IT Instillation
    Dose/Concentration: 5 mg PM or Ti02
    
    Time to Analysis: 6-72 h
    
    
    
    
    
    
    Route: IT Instillation
    Dose/Concentration: 10 |jg 50 |jg 100
    pg/mouse; 0.5, 2.5, 5.0 mg/kg
    Time to Analysis: DMTU 500 mg/kg bw 30 min
    pre-exposure for some mice. Parameters
    measured 18 h post-exposure.
    
    
    
    
    
    
    Effects
    Particles were present in lung parenchyma that was
    removed 12 and 72 h post-instillation.
    
    
    
    
    
    
    
    
    Particle Characteristics: S increased (00-33.20
    pg/mg, Fl- 49.44 pg/mg FU- 122.79 pg/mg) with
    decreasing particle size (mostly in the water-soluble
    fraction). Fe and Cu higher in coarse and fine fractions
    (mostly present in the insoluble). CO PM contained
    more nickel (in both soluble and insoluble) than Fl or
    FU particles. Also, endotoxin levels similar in CO and
    Fl; much lower in FU (0.165 EU/mg).
    
    BALF Cells: PMN increased with exposure for all 3
    fractions ex cept 1 00 pgFI.
    BAL Inflammatory/Injury Markers: Albumin increased
    only at 100 pg Fl. No differences in NAG or LDH
    observed.
                                                                                                   Cytokines: IL-6 increased at 100 pg dose for all 3
                                                                                                   fractions with similar responses. TNF-a increased a
                                                                                                   100 pg dose of fine PM vs control.
    
                                                                                                   Effect of PM After Pre-treatment w/DMTU: Systemic
                                                                                                   administration of DMTU alone depicted a two-fold
                                                                                                   increase in total antioxidant capacity.
    
                                                                                                   DMTU halved neutrophil response observed with
                                                                                                   PMs alone: No fractions were increased over DMTU
                                                                                                   alone which was at least two-fold saline control. IL-6
                                                                                                   concentrations were drastically reduced in the DMTU
                                                                                                   group for the mice exposed to coarse particles (all
                                                                                                   fractions were reduced but only coarse had  a
                                                                                                   significant response). TNF-a levels were decreased
                                                                                                   after treatment with particles and DMTU but treatment
                                                                                                   with particles and saline (control) produced similar
                                                                                                   results.
    Reference: Dybdahl  DEP: SRM 1650 (NIST)
    et al. (2004, 0890131
              	Particle Size: DEP: NR; Control:
                        PM 0.13pm diameter
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/CJ or
    trans-genie
    (MutaMouse)
    
    Age:9-10wk
    
    Weight: -20 g
                                  Route: Nose-only Inhalation
    
                                  Dose/Concentration: I: 20, 80 mg/m3
    
                                  II: 5, 20mg/m3
    
                                  Time to Analysis: I: single exposure 90 min; II: 90
                                  min/day for 4 days; I S II: parameters measured 1,
                                  3, or 22 h post exposure
                                                  Cytokines: A single 90 min DEP exposure increased
                                                  IL-6 gene level dose-dependently in the lung. For 80
                                                  mg/m3 DEP, significantly higher IL-6 gene level was
                                                  observed, both 1 and 22 h post exposure. For 20
                                                  mg/m  DEP, a significantly higher IL-6 level was
                                                  observed at 1 h post exposure but normalized at 3 h.
    
                                                  BALF Cells: Inhalation of DEP did not decrease
                                                  viability of BALF cells. For mice exposed to 20  mg/m3
                                                  DEP, at 1 h post exposure in BAL fluid there was 3 fold
                                                  increase in total cell number.
    
                                                  DMA Damage: Level of 8-oxodG increased post single
                                                  exposure with 80 mg/m3 inducing levels significantly
                                                  higher than controls. Repeated exposures were
                                                  associated with significantly higher DNA strand breaks.
    Reference: Elder et   UFP: argon-filled chamber with
    al. (2004, 0556421    electric arc discharge (TSI,  Inc.,
                        St. Paul,  MN)
    Species: Rat
    
    Gender: Male
    
    Strain: F344, SH
    
    Age: 23 m (Fisher),
    11-14 m(SH)
    Particle Size: 36 nm
    Route: Whole-body Inhalation.
    Dose/Concentration: UFP: 150 pg/m3 bw; LPS: 2
    mg/kg
    
    Time to Analysis: 6 h, 18 h
    BALF Cells: Neither inhaled UFP nor LPS cause a
    significant increase in BALF total cells or percentage
    of neutrophils in either rat strain. No significant
    exposure-related alteration in total protein
    concentration was observed. In both rat strains LPS
    induced a significant increase in the amount of
    circulating PMNs. When combined with inhaled UFP,
    PMNs decreased; for F-344 rats, this decrease was
    significant.
    
    ROS in BALF: In F-344 rats, both UFP and  LPS have
    independent and significant effects on DCFD oxidation.
    Effects were in  opposite directions; particles decreased
    ROS whereas LPS increased ROS.
    December 2009
                                                      D-87
    

    -------
        Reference
              Pollutant
                     Exposure
                        Effects
    Reference: Elder et
    al. (2004, 0873541
    
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344
    
    Age: 21 mo
    Freshly generated vehicle
    exhaust emissions from I-90
    between Rochester and Buffalo,
    NY
    
    Particle Size: NR
    Route: Whole-body Inhalation; IT Instillation
    (Influenza)
    
    Dose/Concentration: Vehicle exhaust: 0.95-
    3.13x105 particles/cm3
    
    Endotoxin: 84 EU
    
    Influenza (IV): 10, 000 EID 50 in 250 \i\
    
    Time to Analysis: 1 *6 h, 3^6 h or both.
    Parameters measured 18 h post-exposure. 48 h
    prior toon-road exposures, instilled intratracheally
    with IV Immediate pre-exposure of priming agent
    endotoxin.
    
    EXPERIMENTS
    1:LPS+PM6h
    2:LPS+PM6h, 3x6h
    3:IV+PM6h
    4:IV+PM6h, 3x6h
    No departures from normal baseline cellular or
    biochemical values were observed, suggesting that on-
    road exposures were well tolerated by the rats.
    
    BAL Inflammatory/Injury Markers: Increase in total
    protein concentration, LDH and B-glucuronidase
    activities were observed.
    
    Specific results according to groups 1-4 are as
    follows:
    
    Experiment 1: No endpoints revealed significant
    differences between groups of rats exposed to gas
    phase only versus the gas-phase/particle mixture.
    
    Experiment 2: Combination of endotoxin and particles
    produced greater inflammatory responses than those
    treated with saline and particles post 1 day. After 3
    days, no statistically significant changes were noted.
    
    Experiment 3: Influenza virus significantly increased
    ROS release in BALF cells.
    
    Experiment 4: Influenza virus significantly increased
    both percentage of PMNs in BALF and BALF cell ROS
    release.
    Reference: Elder et
    al. (2005, 0881941
    
    Species: Rat,
    Mouse, Syrian
    Golden Hamster
    
    Gender: Female
    
    Strain: F-344,
    B6C3F1FIB
    HSCb: Printex-90 high surface
    area carbon black, Deguss-
    Huels (Trostberg, Germany).
    
    LSCb: Sterling V, low surface
    area carbon black, Cabot
    (Boston, MA)
    
    Particle Size: HSCb = 14 nm,
    LSCb = 70 nm
    Reference: Whole-body Inhalation
    
    Dose/Concentration: 0,1, 7, 50 mg/m3 HSCb; 50
    mg/m3 LSCb (rats only)
    
    Time to Analysis: 6 h/day, 5 daus/wk for 13 wk.
    
    Parameters measured 1 day, 3 mo, 11 mo post-
    exposure
    Body Weight: Environmental changes pre and post-
    exposure affected test subjects' life spans, particularly
    hamsters. Hamsters also experienced significant loss
    of body weight when exposed to high doses of HSCb.
    
    Effects of Carbon Black: In rats,  lung weight of the
    high dose HSCb doubled. After 11  mo, analysis of all
    lungs showed no significant difference. Mice had the
    highest relative lung burdens at the end of exposure
    time but also cleared particles faster at high doses than
    rats. However, clearance slowed over the 11 mo
    recovery period, especially in high dose mice.
    Hamsters showed significant elevations in lung carbon
    black burden for all exposures at all time points.
    Hamsters exposed to high dose HSCb exhibited
    impaired clearance.
    
    BALF Cells: Presence of PMNs was limited to the mid
    and high dose groups. Overall  maximal response was
    reached in mice and hamsters, but not in rats with
    increasing mass dose  of HSCb.
    Reference: Evans
    et al. (2006, 0970661
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    DEP: collected under dry,
    outdoor, ambient conditions from
    tractor exhaust pipe (1985,
    Japanese ISEK11500 cc tractor)
    burning Esso 2000 diesel and
    20/30 mixture of Esso light
    engine oil.
    
    10% UF, 90% fine
    
    Cabosil: amorphous silicon
    dioxide
    
    16%UF, 84% fine
    
    Particle Size: DEP: 30 nm;
    Cabosil: 7 nm
    Route: IT Instillation
    
    Dose/Concentration: 1 mg/rat DEP; 1 mg/rat
    Cabosil
    
    Time to Analysis: Pretreatment with 0.5 unit of
    bleomycin; IT 3 or 7 days
    
    after pre-treatment; 1wk post-IT
    Lung permeability: In bleomycin-treated group,
    obvious inflammatory status and edema within the lung
    was observed. This was shown by significant increases
    in acellular protein and free cells.
    
    Changes in lung: Body weight ratio, lung surface
    protein content, free cell counts, and apical surface
    protein of rat type I cells were only altered by
    bleomycin treatment and not particle exposure.
    December 2009
                                                     D-88
    

    -------
        Reference
                                 Pollutant
                                                                     Exposure
                        Effects
    Reference: Finnerty  Coal Fly Ash (generated at U.S   Route: IT Instillation
    et al. (2007,1564341  EPA National Risk Management
                       Research Laboratory by burning   Dose/Concentration: PM: 200 mg/mouse; 9.1
    Species: Mouse     Montana subbituminous coal     m9/k9
                       under conditions simulating full-   PM+LPS10: 200 mg PM+10 mg IPS
                       scale utility boiler conditions)     PM+LPS100: 200 mg PM+100 mg IPS
    .... ~C7D, „,,                                  IPS: 100 ug
    Strain. C57BL/61    Trgnsition metg|s Qf Cog| R
    Age:12wk         Ash: Fe, Mg, Ti, Mn, V           Time to Analysis: 18 h
    
    Weight: 24.3 ± 0.3 g  Particle Size: >PM25
    Gender: Male
                                                                                                  BALF Cells: No significant differences in platelet
                                                                                                  concentration or white blood cell count in any groups
                                                                                                  were observed. The percentage of neutrophils in-
                                                                                                  creased significantly with PM+LPS100. PMN rose in
                                                                                                  PM groups and increased further with IPS treatment.
                                                                                                  Increases in PM+LPS were groups statistically
                                                                                                  significant. More leukocytes were present in the
                                                                                                  alveolar space in PM+LPS10 compared to the PM
                                                                                                  group. The most severe response was in the
                                                                                                  PM+LPS100 group.
    
                                                                                                  Cytokines: Plasma TNF-a and IL-6 significantly
                                                                                                  increased for the PM+LPS100 group. An additive effect
                                                                                                  of IPS and PM for IL-6 was observed. For saline and
                                                                                                  PM groups, pulmonary TNF-a was below detection
                                                                                                  range. A synergistic effect for TNF-a was observed. A
                                                                                                  less than additive effect for IL-6 was observed.
                                                                                                  Pulmonary TNF-a significantly increased in the PM+
                                                                                                  LPS100 group. Pulmonary IL-6 significantly  increased
                                                                                                  in both PM+LPS groups.
    Reference: Fujimaki  DEP: collected from a 4-cylinder,  Route: Whole-body Inhalation
    et al. (2006, 0966011 2.74 L, Isuzu diesel engine
    
    Species: Mouse     Particle Size: 0.4 |jm
    
    Gender: Male
    
    Strain: IL-6(-/-) and
    WT: B6J129SV
    (control)
    
    Age: 5-6 wk
                                                     Dose/Concentration: 1.0, 3.0 mg/m
    
                                                     Time to Analysis: 12 h/dayfor4wk. Parameters
                                                     measured 1 day post-exposure
                                                                                                  BALF Cells: Treatment significantly increased BAL
                                                                                                  cells from WT mice at both dose levels. The increase of
                                                                                                  macrophages and neutrophils were dose-dependent.
                                                                                                  An increase in lymphocytes were present in WT mice
                                                                                                  with the low dose. No significant increase in cells were
                                                                                                  observed from IL-6 (-/-).
    
                                                                                                  Cytokines: TNF-a largely increased in IL-6(-/-) mice
                                                                                                  exposed to 3 mg/m3 compared to WT mice.  IL-6
                                                                                                  production increased in WT mice exposed to 3 mg/m3.
                                                                                                  CCL3 increased in both WT and IL-6(-/-) at high dose.
                                                                                                  IL-1p remained at the control level.
    Reference: Gerlofs-  RTD: road tunnel dust (obtained   Route: IT Instillation
    Nijland et al. (2005,
    0886521
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH/NHsd
    
    Age: 11-12 wk
    
    Weight: 250-350 g
                       from a Motorway tunnel in
                       Hendrik-ldo-Ambacht, Nether-
                       lands)
    
                       EHC-93
                       (Ottawa, Canada)
    
                       Particle Size: Coarse: 2.5-10
                       pm; fine: 0.1-2.5pm
                                                     Dose/Concentration: 0.3,1, 3,10 mg/kg; EHC-
                                                     93: 10mg/kg
    
                                                     Time to Analysis: 4,  24, 48 h
    BALF Cells: PMN significantly increased in RTD (3
    and 10 mg/kg dose) and EHC-93 exposed animals at
    24 h and decreased by 48 h but remained statistically
    significant. AM numbers decreased for 3 mg/kg RTD
    group at 4 h.
    
    BAL Inflammatory/Injury Markers: Myeloperoxidase
    (measured at 24 h in 1, 3,10 mg/kg RTD groups) was
    elevated in a dose-dependent manner. RTD induced
    time-dependent increases in LDH activity at 24 and 48
    h, although these increases were less than EHC-93
    values at the same time points. Alkaline phosphatase
    increased dose-dependently for RTD at 48 h. GSH
    decreased at 24 h to approximately the same levels in
    0.3,1, and 3 mg/kg RTD dose groups. Uric acid only
    decreased in 1 mg/kg RTD group at 24 h.
    
    Cytokines: IL-6 levels were elevated only at 10 mg/kg
    for RTD and EHC-93 at 4 and 24 h; it remained
    elevated for EHC-93 at 48 h. A dose-dependent
    increase in TNF-a at 4 h for RTD was observed. TNF-a
    levels remained elevated only for the 10 mg/kg groups
    at 24 h and returned to control  levels by 48 h. A dose-
    dependent increase in MIP-2 for all RTD dose groups
    were observed and remained elevated through 48 h for
    both PM types (although values were returning to
    control levels).
    
    Pulmonary Histopathology: A dose-dependent
    increase in the number of inflammatory foci at 24 and
    48 h for 3 and 10 mg/kg RTD groups was observed.
    The response was even greater for the EHC-93
    exposed group at similar time points.
    December 2009
                                                                        D-89
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Gerlofs-
    Nijland et al. (2007,
    0978401
    Species: Rat
    
    Gender: Male
    
    Strain: SH/NHsd
    
    Age: 13 wk
    
    Weight: 250-350 g
    PM samples collected from:
    1. MOB high traffic density
    2. HIA high traffic density
    3. ROM high traffic density
    4. DOR moderate traffic density
    5 MGH low traffic density
    6 LYC low traffic density
    
    Particle Size: Coarse: 2.5-10
    pm; Fine: 0.1 -2.5pm
    Route: IT Instillation
    
    Dose/Concentration: 3,10 mg/kg
    
    Time to Analysis: 24 h
    Age: 12 wk
    
    Weight: 200-300 g
    BALF Cells: Pulmonary inflammation was induced in a
    significant and dose-dependent manner for both dose
    levels. Inflammation in the BALF included airway
    neutrophilia, increased macrophage numbers and mild
    lymphocytosis. Both coarse and fine PM caused dose-
    dependent alveolitis. Fine PM from LYC (10 mg/kg
    dose) also caused some bronchiolitis.
    
    BAL Inflammatory/Injury Markers: LDH was
    significantly increased for all doses of coarse PM and
    for the high dose of fine PM. BALF protein
    concentration was observed predominantly at the high
    dose of coarse PM. Location ROM had evidence of
    attenuated responses with fine PM. Ascorbate concen-
    trations were reduced but were only significant for rats
    exposed to the highest dose of coarse PM fractions
    from the locations MOD, HIA, and LYC.
    
    Cytokines: TNF-a concentrations increased for all
    coarse samples with the exception of  DOR and LYC.
    Fine PM induced similar responses for all sites. MIIP-2
    concentrations increased only at certain sites for
    coarse but not fine PM.
    
    Location-related Differences:  Coarse PM from MOB,
    HIA and MGH induced higher LDH responses than
    other locations. Coarse PM from HIA produced BALF
    protein concentrations higher than LYC and ROM.
    MGH induced greater amounts of BALF protein than
    ROM. Coarse PM from LYC lowered fibrinogen values
    more than PM from location MOB, HIA, and MGH. Fine
    PM showed less differences among the various sites.
    
    Particle Correlation: Fine PM exhibited significant
    correlation between zinc content and BALF cytotoxicity
    markers protein and LDH - mainly from HIA. Fine PM
    also exhibited positive correlations with copper and
    barium. Coarse PM showed positive correlation with
    barium and copper, mainly from MOB.
    Reference: Gerlofs- PM (Prague, Czech Republic;
    Nijland et al. (2009, Duisburg, Germany; Barcelona,
    1903531 Spain) (Prague and Barcelona
    coarse PM organic extracts)
    Species: Rat
    Particle Size: Coarse: 2.5-10
    Gender: Male ^ Fine: 0.2-2.5 pm
    Strain: SH
    Route: IT Instillation
    Dose/Concentration: 7mg/kg
    Time to Analysis: 24 h
    Cytotoxicity (LDH, protein, albumin) and inflammation
    (NAG, MPO, TNF-a were increased by PM, and were
    greatest in the coarse PM fraction. Metal-rich PM had
    greater inflammatory and cytotoxic effects. PAH content
    influenced greater inflammation (including neutrophils),
    and cytotoxicity. Generally, whole PM and coarse PM
    were more potent than organic extracts and fine PM,
    respectively.
    Reference: Ghio et
    al. (2005, 0882721
    
    Species: Rat
    
    Gender: Male
    
    Strain: N8 b/b
    Belgrade rats and
    N8+ Ib Belgrade
    controls
    Oil Fly Ash (Southern Research
    Institute, Birmingham, AL)
    
    Particle Size: 1.95 +0.18 fjm
    (MM AD)
    Route: IT Instillation
    
    Dose/Concentration: 500 pg/rat; 2 mg/kg
    
    Time to Analysis: 24 h
    BALF Cells: Homozygous Belgrade with mutation
    G185R had higher levels of Fe and V 24 h post-
    exposure. This may demonstrate a decreased ability to
    remove Fe and V from the lower respiratory tract than
    heterozygous +lb littermates. This also indicates that
    DMT1 is normally responsible for at least some Fe and
    V uptake; thus, a defective DMT1 transports less.
    
    BAL Inflammatory/Injury Markers: Increased protein
    and LDH concentrations in the homozygous strain were
    observed when compared to control
    Reference: Ghio et
    al. (2005, 0882751
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 60 day
    
    Weight: 250-300 g
    Ferric ammonium citrate (FAC)
    
    Vanadyl sulfate (VOS04)
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 0.5 mL 100 pm FAC/rat; 0.5
    mL 10 pm VOS04/rat; 500 pg oil fly ash; 2 mg/kg
    
    Time to Analysis: Single or double exposure with
    24 h rest period. Parameters measured 15, 30, 60
    min, 24 h post-exposure.
    DMT1 Immunohistochemistry and Lung Injury: FAC
    increased and VOS04 decreased -IRE DMT1 staining.
    Same exposures had no effect on +IRE DMT1. -IRE
    DMT1 expression in macrophages,  airway and alveolar
    epithelial cells increased with increased Fe exposure.
    Vanadium nearly eliminated staining except in alveolar
    macrophages. Increased metal clearance with pre-
    exposure to FAC. Less metal clearance with pre-
    exposure to VOS04. Pre-exposure to iron diminished
    lung injury whereas pre-exposure to vandium increased
    lung injury after oil fly ash instillation. Lung injury
    measured by concentration of protein and LDH in BAL.
    December 2009
                                                     D-90
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Gilmour
    et al. (2007, 0964331
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 10-12 wk
    
    Weight: 20-22 g
    PM-CO, Fl, UF
    (obtained from U.S. Seattle (S),
    Salt Lake City (SL), South Bronx
    (SB), Sterling Forest (SF))
    
    SB: included 35% sulfate, 22%
    gasoline, diesel and brake wear.
    
    SF: 48% sulfate.
    
    SL: 34% wood combustion and
    28% sulfate
    
    S: 39% wood combustion and
    29% sulfate
    
    Residual oil combustion and soil
    dust less than 5% for all sites.
    
    Particle Size: CO: 2.5-10 pm;
    FI:<2.5|jm;UF:<0.1 pm
    Route: Oropharyngeal Aspiration                 BALF Cells: PMN increased with the high dose of CO
                                                 samples from SB, SL, S, but not SF. No significant
    Dose/Concentration: 25 pg or 100 pg PM; 1.25 or increases from Fl were observed, though the high dose
    5 m9'k9                                      induced increased PMN. UF from SL caused a highly
    Time to Analysis: 18 h                         variable response.
    
                                                 BAL Inflammatory/Injury Markers: Seattle CO
                                                 fractions showed no dose-dependent effect on protein
                                                 concentration. Results for other locations were
                                                 distinctly higher with 100 pg dose than 25 pg and
                                                 saline doses. SL CO high dose induced the most
                                                 significant increase.  LDH response was weakly dose-
                                                 related. Only SB showed a statistically significant
                                                 increase for LDH with the high dose UF.
    
                                                 Cytokines: MIP-2 was similar to PMN response. SB
                                                 CO induced the most significant response. SL UF was
                                                 highly variable.
    
                                                 Particle Characteristics: LPS was higher in S (CO, Fl,
                                                 UF) and SL (CO, Fl, UF). Zn levels were highest in SB
                                                 (CO, Fl, UF). Fe was higher in all CO and Fl samples
                                                 with SB CO inducing the highest.
    Reference:
    
    Gilmour et al. (2004,
    0574201
    
    Species: Mouse
    
    Gender: Female
    
    Strain: CD1
    
    Age:8-10wk
    
    Weight: 20-25 g
    Coal Fly Ash
    MU: Montana Ultrafme
    MF: Montana Fine
    MC: Montana Coarse
    KF: W. Kentucky Fine
    KC: W. Kentucky Coarse
    
    Particle Characteristics:
    Montana Sulfur 0.83%, Ash
    11.72%. Trace amounts of Ba, P,
    Sr, V, Nb, Cd, Se, Ga, Cu.
    Depleted in Si, Al, Fe, Mg, Ti.
    Kentucky Sulfur 3.11%, Ash
    8.07%
    
    Particle Size: Coarse: >2.5  pm;
    Fine: <2.5|jm;
    Ultrafme: <0.2 pm
    Route: Oropharyngeal Aspiration
    
    Dose/Concentration: 25 ug or 100 pg/mouse
    
    Time to Analysis: 18 h
    BALF Cells: PMN highly increased for MU at both
    doses. The level was comparable to the positive
    control. PMN also increased with KF at high dose.
    Coarse particles caused no significant increase in
    PMN. Number of macrophages did not change, but
    NAG increased significantly with  MU for both dose
    levels and with  KF and MF at high dose level.
    
    BAL Inflammatory/Injury Markers: Total protein and
    LDH was not significantly elevated. Albumin
    concentration increased significantly after treatment
    with the fine high dose of both particle types.
    
    Cytokines: MU particles caused  a significant increase
    in TNF-a. MIP-2 increased in all fine and ultrafme PM-
    instilled animals with the highest  in the MU and KF at
    both doses. IL-6 was detectable only in the BALF of
    MU and KF with substantial variability. The IL-6 levels
    were not significant.
    Reference: Gilmour
    et al. (2004, 0879481
    
    Species: Rat
    
    Gender: Male
    
    Strain: SH/NQIBR,
    WKY
    
    Age: 12 wk
    
    Weight: 280-340 g
    PM (collected from precipitator
    unit of an oil burning power plant
    in Boston)
    
    Measured Components of PM:
    S, Zn, Ni, V,AI, Cu, Pb, Fe, Ca,
    Na, K, Mg, Endotoxin
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 0.0, 0.83, 3.3, and 8.3
    mg/kg in SH rats; 0.0 or 3.3 mg/kg in WKY and SH
    rats
    
    Time to Analysis: 24 h
    BALF Cells: No increase in macrophage number was
    observed in either rat strain following saline or PM
    exposure at 24 h.
    
    BAL Inflammatory/Injury Markers: LDH activity
    increased in a dose-related manner; this was observed
    in SH rats after exposure to 0.83, 3.33 and 8.3 mg/kg
    PM. SH rats showed greater lung permeability following
    PM exposure than WKY rats. SH rats showed acute
    lung  inflammatory response after exposure to PM when
    com pared to WKY rats.
    
    Cytokines: MIP-2 mRNA expression increased
    significantly in SH PM exposure group only. No
    significant differences in TNF-a RNA expression in
    either WKY, SH rats or control treatment groups were
    observed.
    
    CD14: A significant increase in lung CD14 protein was
    observed only in SH rats exposed to PM.
    
    TLR4: A significant increase in TLR4 protein in  SH rats
    exposed to PM was observed.
    
    NF-KB: A significant increase in NF-KB binding  protein
    in the nuclei of SH rats exposed to PM was observed.
    This  effect was not observed in the control of PM-
    exposed WKY rats.
    December 2009
                                                     D-91
    

    -------
    Reference
    Reference: Gilmour
    et al. (2004, 0541751
    Species: Rat
    Gender: Male
    Strain: Wstar Kyoto
    Age: 12 wk
    
    Reference:
    Godleski et al.
    (2002, 1564781
    Species: Rat
    Gender: Male
    
    Strain: SD
    Age: NR
    Weight: 200-250 g
    Reference:
    Gottipolu et al.
    (2009, 1903601
    
    Species: Rat
    Gender: Male
    -
    Strain: Wstar
    Kyoto, SH
    Age: 14-16 wk
    
    Weight: NR
    Reference:
    Gunnison and Chen
    (2005, 0879561
    Species: Mouse
    Gender: Male
    Strain: DK (ApoE"'",
    LDLr'')
    
    Age: 18-20 wk
    Reference:
    Gurgueira et al.
    (2002, 0365351
    Species: Rat
    
    Gender: Male
    Strain: SD
    Weight: 250-300 g
    
    
    
    
    
    
    
    
    Pollutant
    ufCB: Ultrafme carbon black
    (Printex 90 (Degussa)
    CB:(Huber990, HR. Haeffner
    and Co)
    Particle Size: ufCB: 14nm;CB:
    260 nm (primary particle
    diameter)
    
    CAPs (Boston; Harvard Ambient
    Particle Concentrator)
    Particle Size: 0.27 + 2. 3pm
    (diameter)
    
    
    
    
    DE(30-kW(40hp)4-cylinder
    indirect injection Deutz diesel
    engine) (0,- 20%, CO- 1.3-4.8
    ppm, NO- <2.5-5.9 ppm, N02-
    <0.25-1. 2 ppm, S02- 0.2-0.3
    nnm DP/FP H ? + D CfV\
    |J|JIM, \J\slC\s~ U.O ± U.UOJ
    Particle Size: Number Median
    Diameter: Low- 83 + 2 nm, High-
    88.2 nm; Volume Median
    Diameter: Low- 207 + 2 nm,
    High- 225 + 2 nm
    
    CAPS
    (Northeastern regional back-
    ground)
    Ambient air copollutants
    measured 03, N02
    Particle Size: 389 + 2 nm
    
    
    
    CAPs
    (Harvard Ambient Particle
    Concentrator)
    CB
    (C1 98 Fischer Scientific, Pitts-
    burg, PA USA)
    Composed of 85.9+ 0.2%
    Carbon, 13.0+ 0.2% 02, 1.17 +
    0.2% Sulfur
    
    ROFA
    (Boston, MA USA oil-fired power
    plant)
    Particle Size: CAPs: 1-2.5 pm;
    CB: <2.5 pm; ROFA: <2.5 pm
    
    
    
    Exposure
    Route: Whole-body Inhalation
    Dose/Concentration: ufCB: 1.66 mg/m3
    fCB:1.40mg/m3
    Number concentrations
    ufCB: 52380 particles/cm3
    fCB: 3800 particles/cm3
    Time to Analysis: Exposed for 7 h. Sacrificed 0,
    16or48h post-exposure.
    
    Route: Whole-body Inhalation
    Dose/Concentration: 73.5-733 pg/m3
    Time to Analysis: Exposed 5 h/days, 3 days
    (consecutive). BAL 24 h post-exposure
    
    
    
    
    Route: Inhalation
    Dose/Concentration: Low- 507 + 4 pg/m3, High-
    2201 + 14|jg/m3
    Time to Analysis: Exposed 4 h/day, 5 days/wk, 4
    wk. Necropsied 1 day post-exposure.
    
    
    
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: CAPS =131+99 pg/m3
    including 03 = 10 ppb and N02 = 4.4 ppb
    Time to Analysis: 6 h/day, 5 days/wk for 4 mo
    (5/12/03-9/5/03). Sacrificed 3-4 days post-
    exposure.
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: 300 + 60 pg/m3
    Time to Analysis: 1, 3, 5 h CAPs Exposure
    followed by immediate post-exposure analysis.
    5 h CB, immediate analysis.
    SOmin ROFA, Immediate analysis.
    
    
    
    
    
    
    
    
    Effects
    BALF Cells: Total number of cells increased
    significantly in UfCB-exposed rats at 0 and 16 h.
    Recruitment of cells did not occur in response to CB
    exposure. PMNs increased significantly in the BALF of
    ufCB-exposed rats at 16 h. Leukocytes remained
    unchanged following CB exposure but increased
    significantly at 0 and 48 h post exposure to ufCB.
    Cytokine mRNA: A significant increase in BALF MIP-2
    mRNA expression was observed at 48 h. No
    differences in MIP-2 mRNA levels were observed in the
    whole lung tissue.
    BALF Cells and Inflammatory Markers: PMNs
    significantly increased with CAPs exposure and also in
    relation to CAPs mass, Br, S042", EC, OC and Pb. An
    overall increase in pro-inflammatory mediators and
    decrease in immune enhancer and evidence of
    vascular endothelial responses occurred with CAPs
    exposure.
    
    
    
    DE increased neutrophils in a concentration-dependent
    manner, and GGT activity at the high dose. Particle-
    laden macrophages were found in DE-exposed rats.
    
    
    
    
    
    
    
    
    
    Microarray Data: 13 genes in the heart tissue and 47
    genes in the lung tissue were identified as possibly
    affected. Strict standards (1.5 fold response, 10% false
    discovery rate) resulted in responses by only 1/13
    genes (Rex3 - no known heart physiology) in the heart
    tissue and 0/47 genes in the lung tissue. Using more
    liberal response (nonstatistical) standards (1.5 fold
    only) and comparison of each CAPS animal with all 3
    control animals (3x3 array) resulted in possible effects
    on 7 additional genes in the heart tissue and 37 genes
    in the lung tissue.
    In situ Chemiluminescence(CL): Data show a
    significant increase in lung and heart CL at 5 h. Lung
    CL increased linearly with time of exposure.
    Oxidants: CAPs-initiated oxidative stress was not
    detectable in those rats allowed to recover in room air
    after the simulated "peak' in particulate air pollution.
    Rats breathing particle-free filtered air for 3 days had
    significantly lower levels of oxidants. Exposure to inert
    CB did not exert oxidant effects on the heart and lung.
    BAL Inflammatory/Injury Markers: The water content
    of the lung and heart increased significantly upon
    exposure to CAPs but not to filtered air and increased
    as a function of length of exposure. Rats breathing
    CAPs also showed increases in LDH and CPK as a
    function of length of exposure.
    Antioxidant Enzymes: Data showed an increase in
    SOD and catalase activities in both the lung and heart.
    The pattern of increase was tissue specific.
    December 2009
    D-92
    

    -------
        Reference
              Pollutant
                     Exposure
                                                                                                                       Effects
    Reference: Hamoir
    et al. (2003, 0966641
    
    Species: Rabbit
    
    Strain: New
    Zealand
    
    Age: 12-16 wk
    
    Weight: 2.8 +0.5kg
    PSC: Polystyrene particles, Car-
    boxylate modified, 3 types
    
    PSA: Polystyrene particles,
    Amine modified, 1 type
    
    Particle Size: PSC: 24,110 or
    190nm(PSC24, PSC110,
    PSC190);PSA:190nm
    Route: IT Instillation
    
    Dose/Concentration: PSC24: 0.04 or 4 mg/rabbit
    
    PSC110, PSC190, PSA190: 4 mg/rabbit
    
    Time to Analysis: 0, 30, 60, 90,120 min
                                                                                                   Capillary Filtration Coefficient: A time-dependent
                                                                                                   increase correlating to total number of particles/surface
                                                                                                   area, not particle size, was observed. PSA induced a
                                                                                                   significant increase in microvascular permeability as
                                                                                                   compared to PSC. This suggests that the number of
                                                                                                   particles exposed should be considered an important
                                                                                                   parameter for measuring air quality rather than total
                                                                                                   particle surface area.
    Reference: Happo
    et al. (2007, 0966301
    
    Species: Mouse
    
    Gender: Male
    
    Strain: C57BL/6J
    
    Weight: 19-30 g
    
    Age: 10-11 wk
                        PMC (Coarse)
    
                        PMF (Fine)
    
                        PMUF(Ultrafme)
    
                        Collected in 6 European cities:
                        Duisburg, Prague, Amsterdam,
                        Helsinki, Barcelona, Athens
    
                        Particle Size: PMC: PM10-2.5;
                        PMF: PM25-0.2; PMUF: PM0.2
                                  Route: IT Instillation
    
                                  Dose/Concentration: 1, 3,10 mg/kg
    
                                  Time course: 10 mg/kg
    
                                  Time to Analysis: 1. Dose-Response study:
                                  parameters measured 24 h post exposure. 2. Time
                                  course study: parameters measured 4,12, 24 h
                                  post single exposure (at 10 mg/kg).
                                                 BALF Cells: 1. For the dose-response study, all the
                                                 PMC samples exhibited dose-dependent increases of
                                                 total cell numbers. The 3 and 10 mg/kg doses of PMC
                                                 induced statistically significant increases. At 10 mg/kg,
                                                 only 2/6 samples induced statistically significant
                                                 increases. No PMUF samples induced effects at any
                                                 dose. 2. For the time-response study, no increases in
                                                 cell numbers were shown at 4 h. Though the levels
                                                 induced by PMC at 24 h were lower than at 12 h, both
                                                 levels were statistically significant. PMF induced
                                                 statistically significant increases only at 12  h for 4/6
                                                 samples. PMUF induced only 1 significant increase at
                                                 12 h; the 24 h time point was not tested.
    
                                                 BAL Injury Markers: 1. The lower doses of 1 and 3
                                                 mg/kg did not induce significant increases in any of the
                                                 PM samples, except for PMUF-Athens. All 6 samples of
                                                 PMC, at 10 mg/kg, induced significant increases. At 10
                                                 mg/kg,  4/6 PMF samples induced significant increases.
                                                 2. At 4  h, none of the samples increased protein
                                                 concentration. The PMC samples, excluding Prague,
                                                 induced significantly higher concentrations at 12 h. At
                                                 24 h, only 3/6 PMC samples induced significant
                                                 increases. Only 2 PMF samples induced significant
                                                 increases at 12 and 24 h. At 12 h, effects induced  by
                                                 PMUF were minimal and inconsistent; the 24 h time
                                                 point was not tested.
    
                                                 Cytokines: 1. Only PMC induced dose-dependent
                                                 responses that reached statistical significance at 10
                                                 mg/kg.  PMF and PMUF induced minimal and
                                                 inconsistent responses. 2.  TNF-a levels increased
                                                 significantly at 4 and  12 h by PMC. At 24 h, TNF-a
                                                 levels returned to near control levels. PMF, at 4 h,
                                                 induced statistically significant increases for 3/6
                                                 samples and significant increases in 2/6 samples at 12
                                                 h. No PMUF samples significantly increased TNF-a
                                                 levels.  PMC induced  the highest IL-6 levels at 4 h.
                                                 Levels  at 12 and 24 h were reduced with 6/6 and 3/6
                                                 samples showing statistically significant increases,
                                                 respectively. PMF showed a similar trend with 4 h
                                                 inducing the highest levels that were reduced at 12 and
                                                 24 h. Of the PMUF samples, only the Helsinki and
                                                 Duisburg samples induced statistically significant
                                                 results  at 4 and 12 h. Generally, the PMUF responses
                                                 were negligible when compared to PMC and PMF. 2.
                                                 All PMC samples induced the highest levels of KC
                                                 production at 4 h. At 12 and 24 h, levels were reduced
                                                 but 4/6 samples induced statistically significant levels.
                                                 PMF showed a similar trend- the highest levels were
                                                 induced at 4 h (in 3/6 samples). PMUF at 4 h showed
                                                 small, though not significant, increases. At 12 h, only 2
                                                 samples showed statistically significant differences
                                                 from the control; the 24 h time point was not tested.
    Reference: Harder
    et al. (2005, 0873711
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 14-17 wk
    
    Weight: NR
    Carbon UFP
    
    Particle Size: 37.6 +0.7 nm
    (diameter)
    Route: Inhalation
    
    Dose/Concentration: 180 pg/m3
    
    Time to Analysis: 24 h exposure. 3 day recovery.
                                                                                                   UFP induced mild pulmonary inflammation, significantly
                                                                                                   increased PMN, and increased the total protein and
                                                                                                   albumin concentrations. Particle-laden  macrophages
                                                                                                   sporadically accumulated in the alveolar region.
    December 2009
                                                      D-93
    

    -------
        Reference
                                 Pollutant
                     Exposure
                        Effects
    Reference:
    Harkema et al.
    (2004, 0568421
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344, BN
    
    Age: 10-12 wk
    
    Weight: NR
                       CAPs (Detroit; July-Sept. 2000;   Route: Inhalation, IT Instillation.
                       Harvard Ambient Fine Particle
                       Concentrator)                  Dose/Concentration: 4 day concentration: 676 ±
                                                     288 pg/m3, 5 day concentration: 313+119 pg/m3,
                       Particle Size: 2.5 pm (diameter)  July concentration: 16-185 pg/m3, September
                                                     concentration: 81-755 pg/m3; IT Instillation- 200 pL
                                                     (soluble and insoluble)
    
                                                     Time to Analysis: F344 rats sensitized to
                                                     endotoxin, BN rats to OVA. Exposed 10 h/day 1, 4,
                                                     5 days (consecutive). Another group of rats IT
                                                     instilled. Both groups killed 24 h post-exposure.
                                                 The retention of PM in the airways was enhanced by
                                                 allergic sensitization. Recovery of anthropogenic trace
                                                 elements was greatest for CAPs-exposed rats.
                                                 Temporal increases in these elements were associated
                                                 with eosinophil  influx, BALF protein content and
                                                 increased airway mucosubstances. A mild pulmonary
                                                 neutrophilic inflammation was observed in rats instilled
                                                 with the insoluble fraction but instillation of total, soluble
                                                 or insoluble PM25 in allergic rats did not result in
                                                 differential effects.
    Reference:
    Hiramatsu et al.
    (2003, 1558461
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c and
    C57BL/6
    
    Age: 8 wk
    
    Weight: 17-22 g
                       DE: generated by 2369-cc diesel  Route: Whole-body Inhalation
                       engine (Isuzu) at 1050 rpm and
                       80% load with commercial light
    Dose/Concentration: DEP: 100 pg/m3 or 3
                       Particle Size: NR
    mg/m ; S02<0.01 ppm; N02 2.2 ±0.3 or 15 ± 1.5
    ppm;C03.5 ± 0.1 or 9.5 ±0.6 ppm
    
    Time to Analysis: 7h/d, 5 days/wk for 4 or 12 wk,
    Immediate
    BALF Cells: Alveolar macrophages (AMs) increased
    dose-dependently at 30 and 90 day. High DE exposure
    resulted in bronchus-associated lymphoid tissue
    (BALT) around DEP-AMs; this was less conspicuous in
    C57BL/6 than in BALB/c mice. B- and T-cell
    populations were found in the BALT with no significant
    differences observed between the strains.
    Lymphocytes and neutrophils increased time- and
    dose-dependently with a greater increase in  BALB/c
    than C57BL/6 observed. No eosinophils or basophils
    were observed. Mac-1-positive cells exposed to high
    DE levels increased in both strains at 1 month (33.8%)
    and 3 mo (20.3%) vs. low dose group (5.3 and 7%
    respectively).
    
    Cytokines: At 30 days, TNF-a, IL-12p40, IL-4 and IL-
    10 mRNA increased, IL1b and iNOS decreased. IFN-y
    increased in BALB/c but decreased in C57BL/C. IL-6
    mRNA was not affected. At 90 day, IL-4 and  IL-10
    mRNA similarly increased in C57BL/6 mice exposed to
    low DE level but decreased at high DE level.
    Reference:
    Hollingsworth et al.
    (2004, 0978161
    
    Species: Mouse
    
    Gender: Male
    
    Strains:
    C57BL//6TLR*'*,
    C57BL//6TLR"'"
    
    Age: 8-9 wk
                       ROFA
    
                       Particle Size: NR
    Route: Oropharyngeal Aspiration
    
    Dose/Concentration: 50 pi of 1pg/mL suspension
    per mouse
    
    Time to Analysis: Parameters measured post
    single exposure of 6 and 24 h.
    Methacholine sensitivity: No ROFA effect was
    observed in wild type or knockout mice.
    
    BALF Cells: ROFA increased total cell number. Total
    number of neutrophils with lavage fluid increased 24 h
    post-exposure in both strains.
    Reference:
    Hutchison et al.
    (2005, 0977501
    Species: Rat
    
    Gender: Male
                       PM10
                       United Kingdom
                       samples collected before (-B),
                       during closure (-C) and
                       reopening of steel plant (-R)
    Route: IT Instillation
    
    Dose/Concentration: 112 to 180 pg PM in 500 pi;
    0.44-0.72 mg/kg
    
    Time to Analysis: 18 h
                       PMT = PM total (aqueous
                       sonicate)
    Strain- Wistar Kvoto PMS = PM aclueous supernatant
    btram. vvistar Kyoto pM| = pM inso|ub|e pe||et
    
    Age:3m           Particle Size: PM10
    Weight: 250-300 g
    BALF Cells: PMT-R neutrophil cell number and
    percentage were significantly higher than PMT-Cor
    control. PMS-R and PMI-R were also higher than their
    respective controls. The neutrophil cell numbers
    induced by PMI-R were greater than PMI-C and the
    control. Total cell count unchanged.
    
    BALF Inflammatory/Injury Markers: Only albumin
    increased after PMT-R. Upon exposure, total protein
    and LDH did not increase.
    
    Cytokine mRNA expression: Only PMT-R increased
    IL-1B mRNA expression. No effects on TNF-a and
    TGF-B expression  levels were observed. IL-6, MIP2,
    and GM-CSF mRNA was not detected  in BAL cell
    extracts from either the control or treated groups.
    Reference: Inoue et DEP (derived from 4 cyl, 2.74!
    al. (2006, 0978151    light duty diesel engine)
    Species: Mouse
    
    Gender: Male
    
    Strains: C3H/HeJ
    (TLR-4 point mutant)
    and C3H/HeN
    (Control)
    
    Age: 6 wk
                       Particle Size: NR
                                                     Route: IT Instillation
    
                                                     Dose/Concentration: 12 mg/kg
    
                                                     Time to Analysis: 24 h
                                                 BALF Cells: DEP induced an increase in total cells,
                                                 neutrophils, and mononuclear cells. TLR4 knockout
                                                 mice (C3H/HeJ) showed a much lower response.
    
                                                 Cytokines: DEP induced a massive increase in MIP-
                                                 1x, IL-1P and KC. However, levels of MIP-1x were
                                                 significantly less in the knockout than the wild type
                                                 while levels of IL-113 and KC were significantly higher in
                                                 knockouts than the wild type.
    December 2009
                                                                         D-94
    

    -------
        Reference
                                 Pollutant
                     Exposure
                        Effects
    Reference: Inoue et  DEP (derived from 4 cyl, 2.741
    al. (2005, 0974811     light duty diesel)
    Species: Mouse
    
    Gender: Male
    
    Strain: NC/Nga
    
    Age: 10 wk
                        Particle Size: NR
                                                     Route: IT Instillation
    
                                                     Dose/Concentration: 100 pg/mouse
    
                                                     Time to Analysis: 1/wkfor6wk. Parameters
                                                     measured 24 h after last administration
                                                  BALF Cells: DEP significantly increased total cells,
                                                  neutrophils and mononuclear cells but did not induce
                                                  an effect on eosinophils.
    
                                                  Cytokines: DEP increased IL-4, KC and MIP-1. The
                                                  increase in IL-5 was not statistically significant.
    Reference: Ishihara
    et al. (2003, 0964041
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 5 wk
                        DE
                        (from 2 engines, produced on
                        site)
    
                        -L = low level DE
                        -M = medium level
                        -MG = DE w/o particulates
                        -HR = high level
    
                        Measured Components: N02,
                        S04, S02, CO, C02, NOX, NO,
                        HTHC, HCHO, 02
    
                        Particle Size: L: 0.33-0.50 pm
                        M: 0.35-0.40 pm
                        HR: 0.42-0.45 pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: L: 0.18 - 0.21 mg/m3
    M: 0.92-1.18 mg/m3
    MG: 0.01 mg/m
    HR: 2.57-2.94 mg/m3
    
    Time to Analysis: 16h/day, 6days/wk, for 6,12,
    18 & 24 mo. Parameters measured immediately
    following last exposure.
    Morbidity and Mortality: Weight gain in HR group was
    less than other groups at 18 and 24 mo. This indicates
    a significant difference between the HR and C group.
    Mortality during the study was frequent. C group
    experienced an 8% mortality rate, L group 12%, M
    group 15%, MG group 12% and HR group 23%.
    
    BALF Cells: The HR group showed a significant
    increase in total cell count from 6 to 18 mo. The
    percentage of PMN increased at 6mo in M, MG and HR
    group. M group lymphocytes significantly increased at
    6,12, and 24 mo of exposure. Macrophages decreased
    at 6 mo for the M and HR groups.
    
    BAL Inflammatory/Injury Markers: Significant
    differences were seen among groups with respect to
    number of total cells and percentages of cell
    differential, total protein, fucose, sialic acid,
    phospholipid  and prostoglandin  E2. Total protein
    increase was observed in both M and HR dose groups
    with the HR group increasing time-dependently.
    
    Mucus and Surfactant: The HR group showed a
    significant increase from  12 to 18 mo.
    Reference: Jones et ASP: Amorphous silica particles
                       (Hypersil)
    al. (2005, 1988831
    
    Species: Rabbit
    
    Strain: New
    Zealand
    
    Weight: 2.5- 3.5 kg
                        MCSP: Microcrystalline silica
                        particles
    
                        Particle Size: ASP: 5pm;
                        MCSP: 5 pm
    Route: Intrapulmonary Instillation (Right upper
    lobe of lung)
    
    Dose/Concentration: 50mg in 0.5 ml saline
    
    Time to Analysis: Parameters measured at
    varying times from 6 h to 91 days post treatment.
    MCSP: At 6 h, neutrophils increased. Macrophages
    increased 3 fold. At 60 h, neutrophils were pyknotic and
    the lungs displayed a thickened interstitium containing
    silica particles. At 5 days, collagen deposition
    appeared. At 8 days, fibroblastic activity and necrosis
    were observed. At 15 days, aggregation of silica
    particles and necrotic debris were apparent. At 8 wk,
    fibroblasts were still present. At 13 wk, active scarring
    and raised neutrophil macrophage counts were still
    present.
    
    ASP: At 15 h, neutrophils increased. Macrophages
    tripled and remained increased for 3wk. At 4 day,
    macrophages bore particles. At 13 day, neutrophils
    decreased significantly. By 25 day, silica spheres were
    gradually removed from lungs.
    
    PET Scanning: 18F-fluoroproline showed increased
    activity beginning at 14 days and peaking at 41-54
    days.
    
    Microautoradiography: 3 h-proline at 13 wk showed
    radiolabel localization to fibroblasts in the challenged
    lung.
    December 2009
                                                                         D-95
    

    -------
        Reference
              Pollutant
                     Exposure
                                                                                                                       Effects
    Reference: Kato
    and Kagawa (2003,
    Species: Rat
    
    Gender: Male
    
    Strain: Jcl Wistar
    
    Age: 5 wk
    Roadside air
    (Prefectural Tokyo-Danishi-
    Yokohama highway, Yokohama-
    Haneda Airport Metropolitan
    expressway and Satsukibashi-
    Mizuecho city road, Japan)
    
    Particle Size: NR
    Route: Whole-body Inhalation
    
    Dose/Concentration: Exposed group: 62.7 pg/m3
    PM, 557ppbN02,;
    
    Control group: 14.3 pg/m3 PM, 5.1 ppb N02
    
    Time to Analysis: Exposed for 24, 48, 60 wk.
    Parameters measured immediately following
    exposure.
                                                                                                   Respiratory Tissue: Post 24 wk, the lung surface was
                                                                                                   light gray with some BC particle deposits. Post 48-60
                                                                                                   wk, however, the surface was scattered with particle
                                                                                                   deposits in addition to its light gray color.
    
                                                                                                   Airway Changes: After 60 wk, no remarkable changes
                                                                                                   seen in the epithelium. The structure of the airways
                                                                                                   remained normal.
    
                                                                                                   Cells: No proliferation or ectopic growth of goblet cells
                                                                                                   were noted. Mast cells increased in epithelial
                                                                                                   intercellular space. No mast cell degranulation was
                                                                                                   observed. Lysosomes increased in ciliated  cells post
                                                                                                   48 wk. Clara cells were unaffected.
    
                                                                                                   Lymph Nodes: Deposition of carbon particles were
                                                                                                   noted in the trachea and bronchiole-associated lymph
                                                                                                   nodes post 24 wk.
    
                                                                                                   Alveolar Changes: No changes in morphology of
                                                                                                   broncho-alveolar junctions were noted. Anthracosis
                                                                                                   observed within alveolar walls and pleura post 24 wk
                                                                                                   and became progressively marked with increased
                                                                                                   exposure. No change in the number of alveolar holes
                                                                                                   between exposure and control groups were observed.
    Reference: Kato et
    al. (2003, 1988821
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 7 wk
    
    Weight: 190-220 g
    Polystyrene latex suspension of  Route: IT Instillation with nebulizer
    latex beads (Japan Synthetic
    Rubber Co) uncoated or coated  Dose/Concentration: 5 ml of 0.2% suspension
    with lecithin'                   administered over 20 min at flow rate of 0.25
                                  ml/min
    Particle Size: 240 nm
                                                  Alveolar Macrophages: Following treatment, AMs
                                                  appeared undamaged. AMs ingested more uncoated
                                                  than coated beads, but both were ingested. Ingestion
                                                  of beads differed as coated beads were engulfed
                                                  individually while uncoated beads were engulfed
                                  Time to Analysis: Exposed for 20 min.
                                  Parameters measured 30 min following treatment.
                                                  individually or in aggregates.
                                                  Epithelial Cells: Tyf
                                                                                                                  Type I cells incorporated coated
                                                                                                   beads within a layer of cytoplasm. Type II cells
                                                                                                   incorporated beads in lamellar bodies. Uncoated beads
                                                                                                   were not incorporated.
                                                                                                   Other: Neither type of beads were incorporated into
                                                                                                   endothelial cells, fibroblasts or interstitium of alveolar
                                                                                                   wall
                                                                                                   Monocytes: Only the coated beads were incorporated
                                                                                                   by the monocytes.  They were found inside and outside
                                                                                                   phagosomes and lysosomes of monocytes. PMNs did
                                                                                                   not incorporate any beads.
    Reference:
    Kleinman et al.
    (2003, 0535351
    
    Species: Rat
    
    Gender: NR
    
    Strain: F344n-NIA
    
    Age: 22-24 m
                        03
                                  Route: Nose-only Inhalation
                        CCL: 03 + Ammonium bisulfate    Dose/Concentration: 03: 0.2 ppm
                        (ABS) + Elemental Carbon (EC)
    
                        CCH:03 + ABS+EC
    
                        Purified Air (control)
    
                        Particle Size: CCL: 0.30 ± 2.5
                        |jm;CCH: 0.29 + 2.3pm
                                  CCL: 50 pg/m3 EC + 70 pg/m3 ABS + 0.2 ppm 03
    
                                  CCH: 100 pg/m3 EC + 140 pg/m3 ABS + 0.2 ppm
                                  03
    
                                  Time to Analysis: 4 h/days, 3 consecutive
                                  days/wk for 4 wk
                                                  BALF Cells: CCL and CCH induced macrophage
                                                  respiratory burst activity. The effect induced by 03 was
                                                  not significant.
    
                                                  BAL Inflammatory/Injury Markers: Total protein,
                                                  mucus glycoprotein and albumin were somewhat
                                                  elevated in all exposure groups but only reached
                                                  statistically significance for CCL and protein (very high
                                                  variability). CCL and CCH both depressed Fc receptor
                                                  side binding. No effect for 03 was observed.
    
                                                  DMA Replication: 03 caused a slight effect of 20-40%
                                                  increase. CCL and CCH caused between 250 - 340%
                                                  increase for interstitial and epithelial cells. CCL induced
                                                  greater reactions than the high dose.
    Reference:
    Kleinman and
    Phalen (2006,
    0885961
    Species: Rat
    
    Gender: Male
    Strain: SD
    Age: 6 wk
    Weight: 200 g
    
    
    
    
    L03: Low 03
    H03: High 03
    LS: Low H2S04
    HS: High H2S04
    LOLS: Low 03 + Low H2S04
    LOHS: Low 03 + High H2S04
    HOLS: High 03 + low H2S04
    HOHS: High 03+ high H2S04
    
    Particle Size: LS = 0.23 pm +
    2 3
    HS = 0.28 |jm + 2.1
    LOLS = 0.23 pm ±2.3
    LOHS = 0.28 pm ± 2.1
    HOLS = 0.23 pm ± 2.3
    HOHS = 0.28 pm ± 2.1
    Route: Nose-only Inhalation
    Dose/Concentration: L03 = 0.30 ppm
    H03 = 0.61 ppm
    LS = 0.48mg/m3
    HS=1.00mg/m3
    LOLS = 0.31 ppm + 0.41 mg/m3
    LOHS = 0.31 ppm +1.04 mg/m3
    HOLS = 0.60 ppm + 0.52 mg/m3
    HOHS = 0.60 ppm + 0.86 mg/m
    Time to Analysis: Exposed for 4 h. Parameters
    measured 42 h post-exposure.
    
    
    Inflammatory Lesions in Lung Parenchyma: Neither
    Type 1 or 2 lung lesions were affected by sulfuric acid
    alone. H03 doubled Type 1 lesions and increased Type
    2 lesions 25-fold. Additions of H2S04 to 03 appeared to
    have a dose-dependent protective effect for both types
    OT issions.
    DMA Synthesis in Nasal, Tracheal and Lung Tissue:
    Increased DNA synthesis was observed at all high 03
    exposures but was not affected by coexposure to
    H2S04.
    Macrophage FcR binding: No effects were observed
    (no data for L03 and H03).
    Macrophage Phagocytosis: All levels of exposure (no
    data for L03 and H03) decreased phagocytosis.
    
    
    December 2009
                                                      D-96
    

    -------
        Reference
                                Pollutant
                     Exposure
                                                                                                                     Effects
    Reference:
    Kodavanti et al.
    (2005, 0879461
    
    Species: Rat
    
    Gender: Male
    
    Strain: WKY and
    SH/NCrlBR
    
    Age: 11-14 wk
                       CAPs (EPA, NC)
    
                       Measured components included
                       Al, Be, Ba, Co, Cu, Zn, Pb, Mn,
                       Ni, Ag, Ti, As.
    
                       Particle Size: 1 day: 1.07-1.19
                       |jm;2days: 1.27-1.48pm
                                                     Route: Whole-body Inhalation
    
                                                     Dose/Concentration: 1 day study: 1138-1765
                                                     pg/m3
    
                                                     2 day study: 144-2758 pg/m3
    
                                                     Time to Analysis: 4 hr (SH only); 4 hr/day, 2 day
                                                     (WKY and SH)
    
                                                     Post-exposure: 1 day: 3 h except study #4,18-20
                                                     h;2day:18-20h
                                                 Breathing Parameters: In a paired analysis of control
                                                 SH and treated SH, treated SH showed an increase in
                                                 expiratory and inspiratory time due to CAPs. The
                                                 treated and control groups of WKY rats did not show
                                                 significant differences.
    
                                                 BALF Cells: In the 2 day study, WKY rats showed
                                                 decreases in total cells; this decrease was associated
                                                 with decreased macrophages. WKY showed an
                                                 increase in  neutrophils.
    
                                                 BAL Inflammatory/Injury Markers: Total protein and
                                                 albumin in WKY rats decreased whereas SH rats
                                                 maintained  the same approximate level. LDH activity
                                                 lowered slightly in both strains.
    
                                                 Cell Membrane Integrity: SH rats showed increased
                                                 GGT (membrane bound enzyme) activity and plasma
                                                 fibrinogen for 5/7 exposures but these increases did
                                                 not appear to be dose-dependent.
    
                                                 Cytokines: Levels were undetermined in SH rats.
                                                 WKY showed slight increases in IL-6, TNF-a, and MIP-
                                                 2 but these increases were not statistically significant.
    Reference: Kooter   CAP-F = fine (Site I)
    et al. (2006, 0975471 CAP-UF = fine + ultrafine (Site
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 12-14 wk
                       (Netherlands)
    
                       Some measured components:
                       Ammonium, nitrate, sulfate ions:
                       56+ 16% CAP-F mass, 17 +
                       6% CAP-UF mass
    
                       Particle Size: 0.15
    -------
        Reference
             Pollutant
                     Exposure
                                                                     Effects
    Reference: Lei et al.
    (2004, 0878841
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Weight: 300-350 g
    CAPs from Asian dust storm
    (Taiwan)
    
    Measured Components: Si, Al,
    S, Ca, K, Mg, Fe, As, Ni, W, V,
    OC, EC, S02, N02, nitrate,
    sulfate
    
    Particle Size: 0.01- 2.5pm
    Route: Nose-only Inhalation
    
    Dose/Concentration: 315.6 pg/m3 (Low) or 684.5
    pg/m3 (High)
    
    Time to Analysis: Low: Exposed for 6 h.
    Sacrificed 36 h post-exposure
    
    High: Exposed for 4.5 h. Sacrificed 36 h post-
    exposure
    
    Pulmonary hypertension induced 2 wk pre-
    exposure.
                                                 BALF Cells: PM induced dose-dependent increases in
                                                 total cells and percentage of neutrophils. No change in
                                                 macrophages, lymphocytes or eosinophils occurred.
                                                 Basophils were highly variable.
    
                                                 BALF Inflammatory/Injury Markers: Dose-dependent
                                                 increases were observed for total protein and LDH.
    
                                                 Cytokines: IL-6 increased dose-dependently (control:
                                                 33.5 ± 7.5, low 165.1  ± 117.2, 273.6 ± 62.8 pg/mL).
    Reference: Li et al.
    (2007, 1559291
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c,
    C57BL/6
    
    Age: 9 wk
    
    Weight: NR
    DEP (2369-cc diesel engine
    manufactured by Isuzu Motor,
    operated at 1050 rpm, 80% load,
    commercial light oil)
    
    Particle Size: NR
                                                     Route: Inhalation
    Dose/Concentration: DEP: 103.1 + 9.2 pg/m3,
    CO: 3.5 + 0.1 ppm, N02: 2.2 + 0.3 ppm, S02:
    <0.01 ppm
                                                 Airway Hyperresponsiveness: Penh values
                                                 increased in BALB/c mice compared to the control at
                                                 day 0, but no significant changes occurred after this
                                                 time. Penh values increased in C57BL/6 mice at 1 wk
                                                 compared to the control but returned to control levels at
    Time to Analysis: Protocol 1: Exposed 7h/day, 5   8 wk
    days/wk. Sacrificed at day 0, week 1, 4, 8. Protocol  BA|_F: Compared to the other strain, the total number
                                                 of cells and macrophages increased significantly at 1
                                                 wk in C57BL/6 mice and at 8 wk in BALB/c mice.
                                                 Neutrophils, lymphocytes, MCP-1, IL-12, IL-10, IL-4, IL-
                                                 13 increased significantly for both strains. No
                                                 eosinophils were found. IL-1|3and IFN-y increased
                                                 significantly in BALB/c mice compared to C57BL/6
                                  2: DE alone or DE+NAC 7h/day, 1-5 days.
                                                                                                  HO-1 mRNAand Protein: HO-1 mRNA was more
                                                                                                  marked in BALB/c mice at 1 wk and C57BL/6 mice at 4
                                                                                                  and 8 wk. HO-1 protein percentage changes from the
                                                                                                  control were greater in BALB/c mice at 1 wk and
                                                                                                  C57BL/C mice at 8 wk.
    
                                                                                                  MAC: NAC inhibited the increased Penh values, total
                                                                                                  number of cells and  macrophages in C57BL/6 mice at
                                                                                                  1 wk and neutrophils and lymphocytes in both strains.
    Reference: Liu et al.
    (2008, 1567091
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 11 wk
    
    Weight: NR
     DEP (5500-watt single-cylinder
    diesel engine generator
    (Yanmar, Model YDG 5500E),
    406 cc displacement air-cooled
    engine, Number 2 Diesel
    Certification Fuel, 40 weight
    motor oil)
    
    Particle Size: -0.1 pm (MMAD)
    Route: Intranasal
    
    Dose/Concentration: Average particle
    concentration: 1.28 mg/m
    
    Time to Analysis: Four groups: saline+air control,
    saline+DEP, A. fumigatus+air, A.fumigatus+DEP. A.
    fumigatus exposure every 4 day for 6 doses. DEP
    exposure 5 h/day for 3 wk concurrent with A.
    fumigatus exposure.
                                                 A.fumigatus+DEP increased IgE, the mean BAL
                                                 eosinophil percentage, goblet cell hyperplasia, and
                                                 eosinophilic and mononuclear cell inflammatory
                                                 infiltrate around the airways and blood vessels
                                                 compared to the A. fumigatus or DEP treatments.
                                                 A.fumigatus+DEP also caused methylation at the IFN-y
                                                 promoter sites CpG-53, CpG-45, and CpG-205.
    Reference: Lopes
    et al. (2009, 1904301
    
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age: 6-8 wk
    
    Weight: NR
    PM (high density traffic; winter
    2004; Sao Paulo, Brazil) (N02,
    CO, S02)
    
    Particle Size: 10 pm (diameter)
    Route: Open-Top Exposure Chamber
    
    Dose/Concentration: 33.86 + 2.09 pg/m3
    
    Time to Analysis: Some rats pretreated with
    papain. Exposed to UAP or filtered air 24 h/day, 7
    days/wk, 2 mo.
                                                 The papain+UAP treatment increased Lm values,
                                                 collagen fibers, and decreased the density of elastin
                                                 fibers over the papain+filtered air treatment. The
                                                 papin+UAP treatment increased 8-isoprotane more
                                                 than any other group.
    December 2009
                                                     D-98
    

    -------
        Reference
             Pollutant
                     Exposure
                                                                                                                      Effects
    Reference:
    Mangum et al.
    (2004, 0973261
    
    Species: Rat
    
    Gender: Female
    
    Strain: CDF
    (F344)/CrlBR
    
    Age: 7 wk
                       Ti02 (DuPont)
    
                       Particle Size: NR
                                  Route: Whole-body Inhalation
    
                                  Dose/Concentration: 10, 50 or 250 mg/m3
    
                                  Time to Analysis: 6 h/day, 5 days/wk, 13 wk.
                                  Parameters measured 0, 4,13, 26, 52 wk post-
                                  exposure.
                                                 OPN (osteopontin) Expression: At 0 wk, OPN mRNA
                                                 expression exhibited a dose-dependent increase. Low
                                                 dose induced a 2-fold increase while the high dose
                                                 induced an almost 100 -fold increase. At 4 wk, the mid-
                                                 dose and high-dose elevated OPN mRNA levels. At 13
                                                 wk, the high dose elevated OPN mRNA levels. No
                                                 significant elevation with mid dose level was observed.
                                                 At 26 wk, the mid and high dose induced elevated OPN
                                                 mRNA levels. At 52 wk, rats in the low, mid and high
                                                 dose groups all indicated elevated levels of OPN
                                                 mRNA. Specifically, the low, mid and high doses
                                                 induced a 3-fold increase, 7-fold increase and 400-fold
                                                 increase, respectively.
    
                                                 OPN Protein in BALF: Data was not reported at 0 and
                                                 4 wk. At 13 wk, protein increased 9-fold (~800 pg/mL
                                                 OPN) at mid dose and 100-fold (-8000 pg/mLOPn) at
                                                 high dose. At 26 wk, the mid and high dose groups
                                                 remained elevated. At 52 wk, protein increased by 2.5
                                                 fold in low dose, 7-fold in mid dose and 166-fold in high
                                                 dose group.
    
                                                 Histopathology: At 52 wk, slight OPN
                                                 immunoreactivity was observed in control and low dose
                                                 group (immunostaining mostly limited to intraalveolar
                                                 MACSJ.Trichrome-stained lung sections from control
                                                 and low dose groups showed no increase  in collagen.
                                                 Rats exposed to mid or high dose groups showed
                                                 areas of lesions.
    Reference: Martin   UAP-BA: Urban Air particles
    et al. (2007, 0963661 (Buenos Airs, Argentina)
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age: 1-2 mo
    Particle Size: <2.5pm
    Route: Intranasal Installation
    
    Dose/Concentration: 0.17 mg/kg
    
    Time to Analysis: 3*day, 3 days/wk, 2 days apart
    (1, 4, 7 day). Parameters measured 1 h post-
    exposure.
                                                                                                  Particle Characteristics: 3 types, ultrafmes <0.2 um
                                                                                                  (inorganics ND), bunched agglomerates of ultrafmes
                                                                                                  and <40 um with aluminum silicates, ions and trace
                                                                                                  metals.
    
                                                                                                  BALF Cells: Increased amount of phagocytes in
                                                                                                  alveolar area, reducing airspace percentage (control
                                                                                                  52.9% ± 1.39, UAP-BA24.7% ± 2.87). Increased
                                                                                                  number of PAS positive cells.
    
                                                                                                  Morphometry: Induced focal inflammatory lesions.
                                                                                                  Accumulation of refractile material in upper and lower
                                                                                                  respiratory tract. PM in phagocytes of bronchiolar
                                                                                                  lumen and alveolar space. No evidence of fibrosis
                                                                                                  and/or collagen changes.
    Reference: Mauad
    et al. (2008, 1567431
    
    Species: Mouse
    
    Gender: Male,
    Female
    
    Strain: BALB/c
    
    Age: 10 day
    
    Weight: Parental:
    21.4 + 4.0-26.3 +
    2.8 g; 15 day-old
    offspring: 7.8+ 1.1 -
    9.0+ 1.0 g; 90 day-
    old offspring: 20.3 +
    2.3-27.4+1.8 q
    PM (busy traffic street Sao
    Paulo, Brazil; Aug. 2005-April
    2006) (N02, S02, CO)
    
    Particle Size: 2.5,10pm
    (diameter)
    Route: Open-Top Chamber
    
    Dose/Concentration: PM25: filtered chamber- 2.9
    + 3.0 pg/m3, nonfiltered chamber-16.9 + 8.3
    pg/m3; Outdoor concentration: PM10-36.3+ 15.8
    pg/m3, CO- 1.7 + 0.7ppm, NO-89.4+ 31.9 pg/m3,
    S02-8.1 + 4.8 pg/m3
    
    Time to Analysis: Nonfiltered exposure 24 h/day
    for 4 mo. Mated at 120 days exposure. After birth,
    30 females and offspring transferred to filtered or
    nonfiltered chamber. Killed 15 or 90 day of age.
                                                                                                  Mild foci of macrophage accumulations containing
                                                                                                  black dots of carbon pigment occurred in the alveolar
                                                                                                  areas on 90 day-old mice. Surface-to-volume ratio
                                                                                                  decreased from 15 to 90 days of age and was higher in
                                                                                                  mice exposed to air pollution. PM exposure reduced
                                                                                                  inspiratory and expiratory volumes at higher levels of
                                                                                                  transpulmonary pressure.
    Reference:
    McDonald et al.
    (2004, 0874591
    
    Species: Mouse
    
    Strain: C57BL/6
    
    Age:8-10wk
    DEE: high load, No 2, No cat
    (620:1 dilution)
    
    DEE-ER (Control): Emissions
    Reduced  (high load, low sulfur
    ECD1) (same dilution)
    (Yanmar diesel generator, 406
    cc, 5500 watt load)
    
    Particle Size: DEE: 110 nm;
    DEE-ER:  NR
    Route: Whole-body inhalation
    
    Dose/Concentration: DEE PM: 236 pg/m3
    DEE-ER PM: 7 pg/m3
    
    Time to Analysis: DEE: 6 h/day for 7 days.
    DEE-ER: 6 h/day for 7 days. RSV administered
    post-exposure for some: single, 4 days. Those not
    infected with RSV sacrificed immediately upon last
    exposure.
                                                                                                  Differences in Exposure Conditions: CO, PM, EC,
                                                                                                  OC, nitrate, alkyne, c2-c212 alkenes, phenanthrenes,
                                                                                                  total particle PAHs, total Oxy-PAHs, benzene, pyrene,
                                                                                                  benzojayrene, zinc were reduced by 90-100% in the
                                                                                                  emissions reduction case. Most other components
                                                                                                  were reduced by around 60%.
    
                                                                                                  DEE vs. DEE-ER Effects: DEE increased viral
                                                                                                  retention and lung histopathology DEE-ER increases
                                                                                                  were not statistically significant.
    
                                                                                                  Cytokines: DEE increased TNF-a, IL-6, IFN-y and HO-
                                                                                                  1. DEE-ER responses were not statistically significant
                                                                                                  (significantly higher variability in DEE-ER controls vs.
                                                                                                  DEE controls).
    December 2009
                                                     D-99
    

    -------
    Reference Pollutant
    Reference: DEP: SRM 2975 (NIST)
    McQueen etal.
    (2007, 0962661 Particle Size: NR
    Species: Rat
    Gender: Male
    Strain: Wistar Kyoto
    Weight: 228-500 g
    Reference: CP: Carbon particles
    Medeiros et al.
    (2004, 096012) PSA: ROFA (solld waste
    incinerator hospital Sao Paulo,
    Species: Mouse Brazil)
    Gender: Male PSB: electric precipitator, steel
    ~ • „„,„, plant, Brazil)
    Strain: BALB/c
    PSA/PSB Characteristics:
    Age: 60 days Generally, PSB had greater
    Weight: 20-30 g «^™*™*ff*
    (10+x), Mn (2x), Rb (60+x), Se
    (7x , Zn (4x). PMA>PMB: Ce
    (3x, Co (10+x), La(100x), Sb
    (15x),V(50x).
    Particle Size: CP: 1.7 + 2.5pm
    (78%<2.5|jm);PMA:1.2±2.2
    pm(98%<2.5pm);PMB:1.2 +
    2.2 pm (98%<2.5 pm)
    Reference: Mutlu et PM10
    al. (2006, 1559941 Collected by baghouse from
    Dusseldorf, Germany
    Species: Mouse
    Particle Size: NR
    Strain: C57BL/6
    Age: 6-8 wk
    Weight: 20-25 g
    Reference: CAPs: produced at Tuxedo, NY
    Nadziejko, et al. laboratory using centrifugal
    (2002, 0874601 aerosol concentrator
    Species: Rat FA: Fine Particle SulfuricAcid
    „ ., ., , Aerosol
    Gender: Male
    UFA: Ultra-Fine Particle Sulfuric
    Strain: SH Acid Aerosol
    Age: 16 wk Particle Size: CAPs: PM25;
    FA: 160 nm; UFA: 50-75 nm
    Reference: Nemmar DEP: SRM 2975
    et al. (2007, 1568001
    Particle Size: <1 pm
    Species: Rat
    Gender: Male
    Strain: Wistar Kyoto
    Age: 16 wk
    Weight: 424 ± 8g
    Exposure
    Route: IT Instillation
    Dose/Concentration: 0.5 mL/rat of 1 mg/mL; 1-
    2.2 mg/kg
    Time to Analysis: 6 h.
    Pre-exposure: Vagotomy (sectioning of vagus
    nerve) or atropine, 1 mg/kg i.p. administered 30
    min prior, 2 and 4 h post.
    Reference: Intranasal Instillation
    Dose/Concentration: CP: 10 pg/mouse; 0.5
    mg/kg
    PSA: 0.1, 1 or 10 pg/mouse; 0.005, 0.05, 0.5
    mg/kg
    PSB: 0.1, 1 or 10 pg/mouse; 0.005, 0.05, 0.5
    mg/kg
    Time to Analysis: Single, 24 h
    Route: IT Instillation
    Dose/Concentration: 100 ng/mouse; 1 pg/mouse;
    10 pg/mouse; 100 pg/mouse
    Time to Analysis: 1-7 days
    Route: Nose-only Inhalation
    Dose/Concentration: CAPS 80, 66 pg/m3; avg 73
    pg/m3
    FA: 299, 280, 119, 203 pg/m3; avg 225 pg/m3
    UFA: 140, 565, 416, 750 pg/m3; avg 468 pg/m3
    Time to Analysis: 1 0 exposures of 4 h each, each
    exposure at least 1 wk apart.
    (2 exposures to CAPs, 4 to FA and 4 to UFA)
    Route: Intravenous Injection
    Dose/Concentration: 0.02, 0.1 or 0.5 mg/kg
    Time to Analysis: single, 24 h
    Effects
    BALF Cells: A 9-fold increase in neutrophils with high
    individual variability in response was observed.
    Bilateral vagotomy prior to DEP reduced neutrophil
    increase to 3 fold. Vagotomy with saline instillation had
    no effect. Atropine reduced neutrophils to levels similar
    to saline response. No differences were observed
    between DEP response in anesthetized when
    compared to conscious animals. Macrophages,
    eosinophilsand lymphocytes remain unchanged.
    Respiratory Response: RMV increased post DEP.
    Vagatomy reduced response by one-third. Atropine pre-
    treatment did not have effect.
    BALF Cells: No change in BAL cell count was seen.
    Quantitative cellular counts increased for perivascular
    area for both groups at all dose levels. Inflammatory
    cells in alveolar septum area only increased for PSA.
    Alveolar Fluid Clearance: At 100 pg/mouse,
    decreased clearance peaked at 24 h and recovered at
    7 days.
    Histology: Evidence of mild lung injury at doses of 100
    pg/mouse or more was seen.
    BALF Cells: Significant increase in total cell number
    was observed. Neutrophils increased but this was not
    statistically significant.
    Wet/Dry Ratio: Exposure did not induce any effects.
    Na, K-ATPase: At 100 pg/mouse, decreased activity of
    Na, K-ATPase in basolateral membranes was
    observed.
    Respiratory Rate: CAPs decreased the respiratory
    rate as did FA at all dose levels. However, the FA-
    induced respiratory rate was not statistically significant
    unless the data was combined. UFA increased this rate
    significantly.
    BALF Cells: Marked cellular influx at all dose levels
    Was observed. Macrophages increased at the high
    dose, but this was not statistically significant. PMN
    increased significantly at all dose levels.
    Wet/Dry Ratio: All dose levels induced increases.
    December 2009
    D-100
    

    -------
        Reference
              Pollutant
                     Exposure
                        Effects
    Reference: Nemmar PS: Polystyrene particles
    et al. (2003, 0879311
               	 PSC: Polystyrene particles, Car-
    Species: Hamster   boxylate modified
    Gender: Male and
    Female
    
    Weight: 100-110 g
    PSA: Polystyrene particles,
    Amine modified
    
    Particle Size: PS, PSC, PSA-
    60: 60 nm; PSA-400: 400 nm
    Route: IT Instillation
    
    Dose/Concentration: 5, 50 or 500 pg/animal;
    0.05, 0.5, 5 mg/kg
    
    Time to Analysis: Single, 10 min post-exposure
    Rose Bengal administered to induce thrombosis,
    immediate study thereafter
    BALF Cells: Both PSA-60 and PSA-400 (PSA-
    60>PSA-400) induced a massive influx of PMNs. PSA-
    60 effect may exhibit some dose-dependency
    
    BALF Inflammatory/Injury Markers: Small increases
    in total protein were seen at 500 pg level for both PSA-
    60 and PSA-400. LDH was increased at all PSA-60
    levels but not for 500 ug PSA-400. Histamine increased
    for all PSA-60 levels and PSA-400 but due to high
    variability only the effect at 500 pg PSA-60 was
    statistically significant.
    Reference: Nemmar DEP: SRM 1650
    et al. (2003, 0974871
    Species: Hamster
    
    Gender: NR
    
    Weight: 100-110 g
                        Particle Size: NR
                                  Route: IT Instillation
    
                                  Dose/Concentration: 50 pg/animal
    
                                  Time to Analysis: Single exposure, parameters
                                  measured 1, 3, 6 or 24 h post- exposure.
                                                 BALF Cells: DEP led to a significant PMN flux at 1 h
                                                 (13% of total cell number), 6 h (22%) and 24 h (37%).
    
                                                 Histamine: Concentrations in BALF were consistently
                                                 elevated starting at 1 h. Plasma histamine did not
                                                 increase until 6 h.
    
                                                 Pretreatment with Histamine Receptor Antagonist:
                                                 A major decrease in DEP induced PMN infiltration was
                                                 seen. No effect on histamine  in BALF or plasma was
                                                 observed.
    Reference: Pereira  Ambient Particles
    et al. (2007,1560191 (Porto Allegre, Brazil)
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 3 m
    Particle Size: <10|jm
    Route: Whole-body Inhalation
    
    Dose/Concentration: P-6: 34, 22 or 225 pg/m3
    
    P-20:139or112|jg/m3
    
    P-l:99|jg/m3
    
    Time to Analysis: P-6: single/continuous for 6 h
    
    P-20: single/continuous for 20h
    
    P-l: intermittent (5 h) periods per day for 4 days
    consecutively
    
    Parameters measured 0 or 24 h post-exposure
    BAL Inflammatory/Injury Markers: An increase in
    lipid peroxidation was statistically significant only for
    the 20 h continuously exposed group. Leukocytes also
    increased at P-20. No change at P-6. Total protein
    remained unaffected at all dose levels.
    
    Wet to Dry Ratio (Oh): No effect was observed.
    Reference:
    Pinkerton et al.
    (2004, 0874651
    Species: Rat
    Gender: Female
    (pregnant),
    Offspring- NR
    Strain: SD
    Age: 10 days
    (pups), Pregnant
    females- 10-1 4 days
    of gestation
    Weight: NR
    Reference:
    Pinkerton et al.
    (2002, 0876451
    Species: Rat
    
    Gender: Male,
    Female
    PM (Fe and soot from
    combustion of acetylene and
    ethylene in a laminar diffusion
    flame system)
    Particle Size: Median diameter:
    72-74 nm; size range: 10-50 nm
    
    
    
    
    
    
    
    
    PM (Fe, Soot) (ethylene, iron
    pentacarbonyl, acetylene
    combined; Fe203; soot: 60% EC,
    40% OC) (CO, NOX)
    Particle Size: Fe (diameter) 40
    nm; Soot (primary particles,
    diameter) 20-40 nm
    Route: Inhalation
    Dose/Concentration: Mean mass concentration:
    243 ± 34 pg/m ; Average Fe concentration: 96
    pg/m3
    Time to Analysis: Exposed 10 days postnatal
    age, 6 h/day, 3 days (consecutive).
    
    
    
    
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: Adult males: Fe- 57, 90
    pg/m3, Soot- 250 pg/m3, Fe+Soot- Fe: 45 pg/m3,
    Total PM: 250 pg/m ; Neonates: Fe+Soot- Low:
    Fe- 30 pg/m3, Total PM: 250 pg/m3, High: Fe- 100
    pg/m3, Total PM: 250 pg/m3
    Time tn Analwcic1 AHiilt malpc pYnncprl tn Fp
    A significant reduction of cell proliferation occurred only
    within the proximal alveolar region of exposed animals
    compared to controls. There were no significant
    differences between the groups for alveolar formation
    and separation within the proximal alveolar region.
    
    
    
    
    
    
    
    
    
    Fe: Only the high dose had significant effects. This
    dose increased total protein in the lavage fluid,
    decreased total antioxidant power, induced GST
    activity, and induced a non-significant, increasing trend
    of GSH and GSSG. IL-1|3, intracellular ferritin, and NF-
    KB increased.
    
    Fe+Soot, Soot: Fe+Soot significantly reduced the total
    Strain: SD
    
    Age: 11-13 wk (adult
    male), 10-12 days
    (neonatal)
    
    Weight: NR
                                  soot, Fe+Soot, or filtered air. Exposed 6 h/d, 3
                                  days (consecutive). BAL, 2 h postexposure, lung
                                  tissue, 24 h postexposure. Neonatal rats exposed
                                  to Fe+Soot 10-12 day-old and 23-25 day-old.
                                                 antioxidant power in BALF and supernatant from lung
                                                 tissue homogenate. Fe+Soot significantly increased
                                                 GSSG, IL-1P, NF-KB, CYP1A1, and CYP2E1. CYP2B1
                                                 increased but was not significant. Soot alone was not
                                                 significant for anything.
    
                                                 Neonates: The high-dose significantly decreased cell
                                                 viability, increased LDH activity, and increased IL-lp
                                                 and ferritin. Both doses significantly increased GSSG,
                                                 GRR, and GST, and decreased total antioxidant power.
    December 2009
                                                     D-101
    

    -------
        Reference
    Pollutant
    Exposure
    Effects
    Reference: Pires-
    Neto et al. (2006,
    0967341
    Species: Mouse
    Gender: Male
    Strain: Swiss
    Age: 6 days
    
    Ambient Air:
    PM25, N02andCB
    (Sao Paulo, Brazil)
    Particle Size: PM2 5
    
    
    
    
    
    
    
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: PM25: 46.49 ug/m3
    Control: 18.62 ug/m3
    I\I02' 59 52 ug/m3
    Control: 37.08 ug/m3
    CB:12.52|jg/m3
    Control: 0 ug/m3
    Time to Analysis: 24 h/day, 7 days/wk for 5 mi
    Nasal Cavity: Increased total mucus and acidic mucus
    at proximal and medial areas of cavity. Nonsecretory
    epithelium declined. No significant changes in amount
    of neutral mucus, volume proportion of neutral mucus,
    volume proportion of total mucus, thickness of
    epithelium, volume proportion of nonsecretory
    epithelium or ratio between neutral and acidic mucus
    were observed.
    Types of Acidic Mucus Cells: Proximal and medium
    D cells increased. Effects on distal cells were equivocal.
                                                     (weaned at 21 days into exposure, mothers
                                                     removed)
    Reference: DEP: generated from idling
    Pourazar et al. Volvo diesel engine
    (2005, 088305) 3
    DEP 300 ug/m comprised of:
    N021.6ppm
    Species: Human NO 4.5 ppm
    CO 7.5 ppm
    Gender: Male and Hydrocarbons 4.3 ppm
    Female (nonatopic & Formaldehyde 0.26 mg/m3
    nonsmokers) Suspended particulates
    Age: 21-28 yr 43x1°W
    Route: Whole-body Inhalation
    Dose/Concentration: DEP 300 pg/m3
    Time to Analysis: Single exposure for 1 h.
    Parameters measured 6 h post exposure.
    Transcription Factors: Exposure induced increased
    cytoplasmic and nuclear immunoreactivity of phos-
    phorylated p38 MAPK in bronchial epithelium.
    Increased nuclear translocation of phosphorylated p38
    and JNK, MAPK as well as increased nuclear
    phosphorylated tyrosine immunoreactivity were
    observed. No change in total or nuclear c-fos
    immunoreactivity was seen. Exposure induced
    increased nuclear translocation of phosphorylated JNK
    significantly associated with phosphorylation of nuclear
    c-jun and also resulted in an increase in nuclear p65.
                       Particle Size: <10|jm
                                                                                                 Cytokines: Expression of IL-8 was positively
                                                                                                 associated with nuclear phosphorylated p38 post-
                                                                                                 exposure.
    Reference: Pradhan RSPM: Respirable Suspended
    et al. (2005, 0961281 PM
                       (Lucknow, India)
    Species: Rat
                       Quartz dust (positive control)
    Gender: Female
                       Particle Size: < 5 urn
    Strain: Wstar Albino
    
    Weight: 120-180 g
                        Route: IT Instillation
    
                        Dose/Concentration: 2.5, 5.0, or 10.0 mg/0.05
                        ml; 20, 42, 83 mg/kg
    
                        Time to Analysis: 15 days.
                                Relative Lung Weight: A dose-dependent increase in
                                total lung weight of RSPM-instilled animals was
                                observed.
    
                                BALF Cells: Exposure induced a dose-dependent
                                increase in total cells dose-dependent with the low and
                                mid dose levels. PMNs increased massively at all dose
                                levels with RSPM inducing less of an increase than
                                Quartz. Exposure at low dose levels resulted in an
                                influx of inflammatory cells (predominantly
                                macrophages into lumen of alveolar ducts and alveoli).
                                Reaction at the high dose was more intense than that
                                seen in mid dose-exposed lungs.
    
                                BAL Inflammatory/Injury Markers: A significant dose-
                                dependent increase in LDH and NO was observed, but
                                the Quartz-induced increase was greater than the
                                RSPM-induced increase. An increase in protein was
                                significant at the mid dose level for RSPM and
                                significant at the high dose level for both RSPM and
                                Quartz.
    
                                Lung  Biochemistry: An increase in lipid peroxidation
                                was dose-dependent. Superoxide dismutase (SOD)
                                enzyme levels showed a dose-dependent decrease.
    Reference: Ramos   WS (Pine wood) (00(<80ppm),   Route: Whole-body Inhalation
    et al. (2009, 1901161  C02 (0.35%), 02 (20.1 %), PM2 5,
    .    .    „ .        PM10)
    Species: Guinea
    Pig                Particle Size: PM2 5, PM10
                        Dose/Concentration: WS: 60 g, PM25:363 ± 23
                        ug/m , PM10: 502 + 34 ug/m
    Gender: NR
    
    Strain: NR
    
    Age: NR
    
    Weight: 330-370 g
                        Time to Analysis: Exposed 3 h, 5 days/wk for 1,
                        2, 3, 4, 6, 7 mo.
                                WS significantly decreased body weight between 4 and
                                7 m exposure. The concentration of blood
                                carboxyhemoglobin increased. Recovered BALF cells
                                were higher in WS-exposed pigs. Macrophages and
                                neutrophils increased. Inflammation in the lungs was
                                seen. Pulmonary arterial hypertension and
                                emphysematous lesions were observed. Macrophage
                                and lung tissue homogenate elastolysis increased.
                                Collagenolysis increased. Generally, MMP-2, MMP-9,
                                and MMP-1  increased. BAL macrophage apoptosis
                                increased with time.
    December 2009
                                           D-102
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Rao et
    al. (2005, 0957561
    
    
    Species: Rat
    
    Strain: SD
    
    Weight: 175 g
    DEP: SRM 2975                Route: IT Instillation
    
    Particle Size: 0.5 pm            Dose/Concentration: 5, 35, 50 mg/kg bw
    
                                  Time to Analysis: Sacrificed 1, 7, 30 days post
                                  single exposure. Cytokines measured after 24 h
                                  incubation (in vitro).
                                                 BALF Cells: Macrophages unaffected. Increased
                                                 PMNs at 1 day for all dose levels, sustained elevation
                                                 at 7days for mid and high dose and at 30 days for all
                                                 dose levels.
    
                                                 BAL Inflammatory/Injury Markers: Increased albumin
                                                 at 1 and 30 days at all dose levels. Increased LDH
                                                 except at low dose at 7 days.
    
                                                 Cytokines: The high dose induced a significant
                                                 increase of mRNA expression for IL-113, iNOS, MCP-1,
                                                 and MIP-2 in BAL cells. MCP-1 mRNA sustained high
                                                 levels at 7 days for mid and high dose and at 30 days
                                                 for all dose levels. mRNA expression of IL-6, IL-10,
                                                 TGF-|31, TNF-awere unaffected. However, IL-6 and
                                                 MCP-1 proteins increased significantly in BALF at 1
                                                 day for mid and high dose, returning to basal levels at 7
                                                 days. MIP-2 increased for all dose levels at all time
                                                 points. NO level unaffected.
    Reference: Reed et
    al. (2006, 1560431
    
    Species: Rat,
    Mouse
    Gender: Male and
    Female
    
    Strain: CDF
    (F344)/CrlBR (rat),
    SH (rat), A/J
    (mouse), and
    C57BL/6 (mouse)
    Aae: 6-1 2 wk
    HWS (burned mix of hardwood
    in noncertified wood stove using
    a Pineridge model 27000,
    Heating and Energy Systems,
    Inc. Clackamas, OR)
    Measured Components: EC,
    OM, N03, S04, NH4, metals
    
    Particle Size: -0.25 pm
    
    
    
    Route: Whole-body Inhalation
    
    Dose/Concentration: Low: 30 pg/m
    Mid-low: 100|jg/m3
    Mid-high: 300 pg/m3
    High: 1000 pg/m3
    
    Time to Analysis: 6 hr/day, 7 days/wk for 1wk or 6
    mo. Immediate post-exposure analysis.
    
    
    
    Organ Weights: Liver declined in rats of both genders
    at 1 wkand female rats at 6 m. Lung volume increased
    and lung weight decreased in female rats at 6 m.
    Spleen weight increased in female mice and rats at 1
    wk. Thymus weight decreased in male rats at 1 wk.
    Cells: Eosinophils decreased and lymphocytes
    increased in males at 6m. Neutrophils decreased at 6m
    in both genders. Minimal increases in alveolar
    macrophages and sparse brown-appearing
    macrophages in all species.
    Bacterial Clearance: Mice instilled with bacteria were
    mostly unaffected by exposure, except for a decline in
    histopathology summary score after 6m.
                                                                                                  Tumorigenesis: No values for exposed groups differed
                                                                                                  significantly from controls. There was no evidence of
                                                                                                  progressive exposure related trend.
    Reference: Reed et DE: generated from two 2000 Route: Whole-body Inhalation
    al. (2004, 055625) model 5.9 L Cummins ISM turbo 3
    diesel engines Dose/Concentration: Low: 30 pg/m
    Species: Rat, ,
    Mouse Co-exposure to 8 gas and 8 Mid-low: 1 00 pg/m
    solid exhaust components . ., . .... ,nn , ,,3
    Gender: Male and measured Mid-high. 300 pg/m
    Female uiinkv innn,,n;m3
    Organ Weights: Kidney weight increased after 6m for
    both males and female rats at the high dose. Kidney
    and liver weight increased for female mice at all dose
    levels at 6 mo. Lung weight increased at high dose at
    6m for female mice and male rats. Spleen weight
    decreased in male mice at the low and mid-high levels.
    Cells: Minimal increases in alveolar macroohaaes and
                       Particle Size: 0.10-0. 15pm
    (F344)/CrlBR (rat),
    A/J (mouse)
    
    Age: 12 wk
                                  Time to Analysis: 6 h/day, 7 days/wk for 1wk or 6
                                  mo. Analyzed 1 day post-exposure.
                                                 PM within the macrophages were seen.
    
                                                 Cytokines: TNF-a decreased in female rats after 6m.
    
                                                 Tumorigenesis: No significant effect was observed.
    Reference: Reed et
    al. (2008, 1569031
    
    Species: Mouse
    
    Gender: Male,
    Female
    
    Strain: C57BL/6,
    A/J, BALB/c
    
    Age: NR
    
    Weight: NR
    GEE (2 1996 General Motors
    4.3-LV-6 engines; unleaded
    gasoline)
    
    Particle Size: 150 nm(MMAD)
    Route: Whole-body Inhalation
    
    Dose/Concentration: Control: 2.5 ± 2.9, Low-
    exposure: 6.6 + 3.7, Mid-exposure: 30.3 + 11.8,
    High-exposure: 59.1 + 28.3, High filtered exposure:
    2.3±2.6|jg/m3
    
    Time to Analysis: Exposed 6 h/day, 7 days/wk, 3
    days-6 mo.
    Body and Organ Weight and Histopathology in A/J:
    Kidney weight decreased, but no effects pertaining to
    weight were significant. No visible inflammatory
    changes were seen.
    
    Lung Damage in A/J: No significant effect was seen,
    but hypomethylation was seen in females at 1wk, and
    methyiation was reduced in all exposed female groups.
    
    Bacteria in Lungs of C67BL/6: Exposure did not
    affect the clearance of bacteria from the lung.
    
    Respiratory Allergic Response in BALB/c: Exposure
    had little effect, but serum total IgE increased
    significantly for the high-exposure group. Increasing
    trends were seen in OVA-specific serum IgE and  lgG1,
    as well as neutrophils and eosinophils.
    December 2009
                                                     D-103
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Reed et
    al. (2008, 1569031
    
    Species: Mouse
    
    Gender: Male,
    Female (only
    BALB/c)
    
    Strain: C57BL/6,
    A/J, BALB/c
    
    Age: NR
    
    Weight: NR
    GEE (two 1996 General Motors
    4.3-LV-6 engines; regular,
    unleaded, non-oxygenated, non-
    reformulated gasoline blended to
    US average consumption for
    summer 2001 and winter 2001-
    2002- Chevron-Phillips)
    
    Particle Size: 150 nm(MMAD)
    Route: Whole-body Inhalation
    
    Dose/Concentration: PM: Low- 6.6 + 3.7 pg/m3,
    Medium- 30.3 ± 11.8 pg/m3, High- 59.1 ± 28.3
    pg/m3
    
    Time to Analysis: A/J - exposed 6 h/days, 7
    days/wk, 3 days-6 mo. C57BL/6- 1wk exposure.
    Instillation of P. aeruginosa. Killed 18 h
    postinstillation. BALB/c- Conditioned to exposure
    chambers and mated. Pregnant females exposed
    GD 1 and throughout gestation. Offspring
    exposures continued until 4 wk-old.  Half of
    offspring sensitized to OVA. Tested for airway
    reactivity by methacholine challenge 48 h post-
    instillation and euthanized.
    The kidney weight of female A/J mice decreased at 6m
    and was strongly related to PM by the removal of
    emission PM. PM-containing macrophages increased
    by 6 mo. Hypomethylation occurred in females at 1 wk.
    The clearance of P. aeruginosa was unaffected by
    exposure. Serum total  IgE significantly and dose-
    dependently increased. OVA-specific IgE and lgG1
    gave slight exposure-related evidence but were not
    significant.
    Reference: Reed et
    al. (2008, 1569031
    
    Species: Rat
    
    Gender: Male,
    Female
    
    Strain: CDF
    (F344)/CrlBR, SHR
    
    Age: NR
    
    Weight: NR
    GEE (two 1996 General Motors
    4.3-LV-6 engines; regular,
    unleaded, non-oxygenated, non-
    reformulated Chevron-Phillips
    gasoline, U.S.  average
    consumption for summer 2001
    and winter 2001-2002)
    
    Particle Size:  150 nm(MMAD)
    Route: Whole-body Inhalation
    
    Dose/Concentration: PM: Low- 6.6 ± 3.7 pg/m3,
    Medium- 30.3 ± 11.8 pg/m3, High- 59.1 ± 28.3
    pg/m3
    
    Time to Analysis: 6 h/day, 7 days/wk, 3 days-6
    mo.
    Organ Weight: At 6 mo. exposure, the heart weights of
    male and female rats increased and male rats' seminal
    vesicle weight decreased.
    
    Histopathology: PM-containing macrophages
    increased by 6 mo.
    
    Lung DMA Damage: Hypermethylation occurred in
    medium- and high-exposure male rats at 6 mo.
    
    BAL: For both genders in the high-exposure group,
    LDH and MIP-2 significantly increased at 6 mo. ROS
    decreased at Iwkand 6 mo. Generally, the production
    of hydrogen peroxide and superoxide decreased in the
    high-exposure group and medium- and high-exposure
    groups, respectively.
    
    Removal of Emission PM: The removal of emission
    PM strongly linked PM to increased seminal vesicle
    weight, red blood cell counts, LDH, lipid peroxides, and
    methylation.
    Reference:
    Rengasamy et al.
    (2003, 1569071
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Weight: -200 g
    DEP:SRM1650
    CBEIftex-12 furnace black,
    Cabot, Boston, MA
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 5,15, or 35 pg/kg
    
    Time to Analysis: Single; 1, 3, 5, 7 days post
    exposure
    CYP1A1: DEP at all doses significantly increased
    CYP1A1 protein, was maximal at 1 day, and
    normalized at 5 days. CB had no effect.
    
    CYP2B1: DEP and CB at 15 and 35 mg/kg inhibited
    activity at 1 day
    Protein level significantly decreased at 1 day with 5,15
    and 35 mg/kg DEP and at 15 and 35 mg/kg CB. A time
    dependent decrease was shown at 35 mg/kg for both
    DEP and CB.
    Reference: Renwick
    et al. (2004, 0560671
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wstar Kyoto
    
    Weight: 370-470 g
    FCB: Fine Carbon Black (Huber
    990)
    UCB: Ultrafme Carbon Black
    (Printex 90, Degussa)
    FTO: Fine Titanium Dioxide
    (Tioxide)
    UTO: Ultrafine Titanium dioxide
    (Degussa)
    
    Particle Size: FCB: 260 nm;
    UCB:14nm;FTO:250nm;
    UTO: 29 nm
    Route: IT Instillation
    
    Dose/Concentration: 125 or 500 pg/rat
    
    Time to Analysis: Single, 24 h
    BALF Cells: UTO and UCB induced a large dose-
    dependent increase in percent neutrophils (only
    statistically significant at 500 pg for UTO).
    
    BAL Inflammatory/Injury Markers: UTO and UCB
    also increased total protein content only at the 500 pg
    dose. UCB induced LDH release at 125 and 500 pg,
    UTO and CB at 500 pg. UTO and UCB induced large
    dose-dependent increases in GGT activity (only
    statistically significant at 500 pg for UTO).
    
    Phagocytosis: All 4 particles decreased but only at the
    500 pg level.
    
    Chemotaxis: Only UTO and UCB at 500 pg/l
    increased chemotactic migration.
    December 2009
                                                    D-104
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Rhoden  CAPs
    et al. (2004, 0879691 (Boston, MA)
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Weight: 250-300 g
    Particle Size: CAPS: 0.1-2.5 pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: 1060 + 300 pg/m3
    
    Time to Analysis: Single exposure for 5 h.
    Analyzed 24 h post-exposure.
    
    (CAPS-MAC = CAPS with 50 mg/kg bw MAS (N-
    acetylcysteine) pretreatment)
    Particle Characteristics: Major components did not
    appear to show any correlation to total particle mass.
    Included Na, Mg, Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe,
    Ni, Cu, Zn, Br, Ba, Pb. Metals Al, Si and Fe (somewhat
    less for Pb, Cu, K) correlated with TBARS.
    
    BALF Cells: CAPS increased PMN 4 fold.  MAS
    treatment reduced this increase to control levels.
    
    BAL Inflammatory/Injury Markers: LDH and total
    protein not affected. Histology confirms slight
    inflammation with CAPS and no inflammation with
    CAPs-NAC.
    
    Oxidative Stress: CAPS increased TBARS and
    oxidized protein by 2+ fold. MAS fully prevented the
    increase in TBARS and partially prevented an increase
    in protein carbonyl.
    
    Tissue Damage: Wet/dry ratio increased with CAPS
    but significantly decreased with MAC.
    Reference: Rhoden
    et al. (2008, 1904751
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: NR
    
    Weight: 300 g
    Urban Air Particles (UAP) (SRM
    1649)
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 1mg in 100 |JL saline
    
    Time to Analysis: Instilled with UAP. CL
    analysis:15 min post-exposure. BAL
    measurements: 4 h post-exposure.
    
    Some rats pre-treated with MnTBAP 2 h prior to
    UAP exposure.
    UAP significantly increased the total cell number, PMN,
    MPO activity, and protein levels. MnTBAP prevented
    UAP-induced lung inflammation. UAP increased
    oxidants in lung CL, which was prevented by MnTBAP.
    Reference: Rivero
    et al. (2005, 0886531
    
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar Kyoto
    
    Age: 3 mo.
    
    Weight: 250 g
    Ambient air (Sao Paulo, Brazil)
    
    Particle Size: <2.5pm
    Route: IT Instillation
    
    Dose/Concentration: 100 or 500 pg/rat; 0.4 or 2
    mg/kg
    
    Time to Analysis: Single, 24 h
    Histopathology: At both doses, acute alveolar
    inflammation was observed and was more pronounced
    in the 500 pg group.
    
    Lung Morphometry: Lumen wall ratio values show a
    dose-dependent increase in peribronchial as well as
    intra-acinar pulmonary arterioles. No effect in
    myocardial arterioles were observed.
    
    Tissue Damage: Lung wet/dry ratios were unaffected.
    Reference: Roberts
    et al. (2004, 1989031
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 60-90 days
    
    Weight: 300-350 g
    ROFA: SRI (cyclone power
    plant)
    
    Particle Size: NR
    Route: IT Instillation
    
    Dose/Concentration: 0.5 mg/rat; 1.67 mg/kg
    
    Time to Analysis: Single, 6 and 24 h
    Technology: Laser capture microdissection of airway
    cells were used to analyze results.
    
    Protein: pERK1/2: ERK1/2 ratio increased by 60% at
    6 h and 80% at 24 h. NF-KB activity increased at 6 h
    but was not statistically significant.
    Reference: Saber et
    al. (2005, 0978651
    
    Species: Mouse
    
    Gender: Female
    
    Strain: TNF(-/-) (B6,
    129S-Tnftm1Gk1),
    C57/BL
    
    Age:9-10wk
    DEP: SRM 2975
    
    CB: Printex 90 (Degussa)
    
    Particle Size: DEP: 215 nm;
    CB: 90 nm
    Route: Nose-only Inhalation
    
    Dose/Concentration: DEP: 20 mg/m3; CB: 20
    mg/m3
    
    Time to Analysis: 90 min/day for 4 days
    consecutively, 1 h
    BALF Cells: Neutrophils increased significantly to 15%
    when compared to control (4%) with DEP exposure. No
    response difference was observed between TNF (+/+)
    and TNF(-/-). CB did not induce any changes in
    neutrophil numbers.
    
    Cytokines: IL-6 increased 2-3 fold in DEP and CB
    exposure in both normal and knockout mice. IL-1|3was
    unaffected.
    
    mRNA: In TNF (+/+) mice, DEP and CB increased
    expression of TNF mRNA 2-fold. IL-6 mRNA
    expression was high in DEP-exposed knockout mice
    when compared to normal mice.
    
    DMA:  DNA strand breaks increased in both strains.
    Knockout mice showed  a higher response to CB and
    DEP exposure. For normal mice, only CB induced a
    statistically significant effect.
    December 2009
                                                    D-105
    

    -------
        Reference
             Pollutant
                                                  Exposure
                                                                     Effects
    Reference: Schins
    etal. (2004,
    0541731
    Species: Rat
    
    Gender: Female
    
    Strain: Wistar Kyoto
    
    Weight: 350-550 g
    Soluble fractions
    PMC:PM10.25
    PMF: PM25
    -B: Borken, Germany (rural)
    -D: Duisburg, Germany (industri-
    alized)
    
    Particle Size: PMio-2.5, PM2.5
    Route: IT Instillation
    
    Dose/Concentration: 0.32 + 0.01 mg/rat; 0.91+
    0.58 mg/kg
    
    Time to Analysis: Single, 18 h
                                                                               BALF cells: Both PMC showed a massive increase in
                                                                               neutrophils. PMC-B induced the greatest increase
                                                                               followed by PMC-D. Both PMF did not induce a
                                                                               significant increase.
    
                                                                               BAL Inflammatory/Injury Markers: PMC from both
                                                                               sites induced markedly higher endotoxin concentration
                                                                               vs PMF as follows in decreasing order: PMC-B, PMC-
                                                                               D, PMF-B, PMF-D, control. Glutathione decreased only
                                                                               for PMC-B. LDH and total protein were unaffected.
    
                                                                               Cytokines: TNF-a and IL-8 increased with PMC from
                                                                               both sites. PMF induced a slight increase in IL-8 but did
                                                                               not induce an increase in TNF-a.
    
                                                                               Radical Formation: Formation of hydroxyl radicals
                                                                               increased with exposure. Relative intensity was: PMC-
                                                                               D, PMF-D, PMC-B, PMF-B, and control.
    Reference:
    Seagrave etal.
    (2005, 0880001
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344/DCrl
    BR
    
    Age: 11 +1  wk
                       PM from 3 sources:
                                                     Route: IT Instillation
    NT: New Technology bus, Detroit  Dose/Concentration: 0.25-2.2 mg/rat in 0.5ml
    Diesel 50G, exhaust oxidation     saline
    catalyst, 216 miles, 2002 model -
    jn use                         Time to Analysis: Single, 24 h
    
    NE: Normal emitter bus, Detroit
    Diesel 50G, no catalyst, 134259
    miles, 1997 model - in use
    
    HE: High Emitter bus, Cummins
    L10G, no catalyst, >250, 000
    miles, 1992, retired
    
    Fuel composition very similar for
    3 vehicles: methane (96-96.8%),
    ethane (1.6-1.9%), carbon
    dioxide (0.9-1.1%), nitrogen (0.6-
    0.8%), traces of other gases
    
    Particle Size: NR
                                                                               Engine Specific Emission data: HE had significantly
                                                                               higher PM and SVOC recovered emission rates than
                                                                               NEandNT.
    
                                                                               Organic mass in PM: The following PM sources are
                                                                               listed in decreasing order of percent of total mass: HE,
                                                                               NE, NT.
    
                                                                               Total PAH: The following PM sources are listed in
                                                                               decreasing order of total mass: HE, NT, Control, NE.
    
                                                                               Nitro PAH: The following PM sources are also listed in
                                                                               decreasing order of total mass: NE, HE, Control, NT.
                                                                               Authors note confounding technical issues (mostly
                                                                               technique  related) with mostly mild effects.
    
                                                                               BAL Inflammatory/Injury Markers: LDH showed
                                                                               dose-dependent increases with HE inducing higher
                                                                               increases than NT and NE. Total protein exhibited
                                                                               dose-dependent increases with HE,  NT and the
                                                                               positive control SRM2975 inducing higher levels than
                                                                               NE.
    
                                                                               Potency Factors Cytotoxicity and  Inflammation: HE
                                                                               was significantly more potent than NT and NE, with NT
                                                                               also showing significant potency.
    
                                                                               Lung Toxicity: The results were highly variable but the
                                                                               general toxicity levels in increasing order is the
                                                                               following: NE, NT, HE, Normal gasoline, diesels, and
                                                                               high gasolines, though individual factors may differ
                                                                               greatly.
    Reference:
    Seagrave et al.
    (2006, 0912911
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344/Crl BR,
    
    Age: 11 +1 wk
    PM25 sources: BHM: Birming-
    ham, Alabama; urban
    JST: Jefferson Street, Atlanta,
    Georgia; urban
    PNS: Pensacola, Florida; urban/
    residential
    CTR: Centreville, Alabama; rural
    "smoke" = downwind of forest
    fires/burns (NR)
    
    Particle Size: PM2 5
                                  Route: IT Instillation
    
                                  Dose/Concentration: 0.75,1.5, 3 mg/rat
    
                                  Time to Analysis: Single, 24 h
                                                 BALF PMN: In general, the winter samples induced
                                                 greater increases in potency than the summer samples
                                                 except for PNS. For the winter samples, the samples
                                                 that induced the greatest increases, in descending
                                                 order, are: JST, BHM, CTR, PNS and Smoke. For the
                                                 summer, the samples that induced increases, in
                                                 descending order, are: BHM, JST,  PNS, and CTR.
    
                                                 BALF Macrophages: For the winter, the BHM and JST
                                                 samples significantly increased potency whereas the
                                                 PNS sample induced  significantly negative potency.
                                                 For the summer,  only the BHM sample significantly
                                                 induced potency.
    
                                                 BALF Lymphocytes: Only the JST-Wand BHM-W
                                                 significantly increased potency. The BHM-S, CTR-S
                                                 and PNS-S also significantly increased potency.
    
                                                 Histopathology: All the winter and summer samples,
                                                 excepting PNS, significantly induced inflammation.
    
                                                 Lung weight/body Weight Ratio: In general,  for all
                                                 end points, JST-S was significantly less potent than
                                                 JST-W. The summer samples of BHM and CTR were
                                                 also generally more potent than their winter
                                                 counterparts.
    December 2009
                                                    D-106
    

    -------
    Reference
    Reference:
    Seagrave et al.
    (2005, 0880001
    
    Species: Rat
    Gender: Male,
    Female
    
    Strain: CDF(F-
    344)/CrlBR
    Age: 10-12 wk
    
    
    
    
    
    
    
    
    
    
    
    
    Reference:
    Seagrave et al.
    (2008, 1919901
    Species: Rat
    Gender: Male
    Strain: SD
    Pollutant
    DE:
    (Two 6 cyl Cummins ISB turbO)
    HWS = hardwood smoke
    (mixed black/white oak,
    uncertified conventional wood
    stove)
    
    DE:
    ,
    EC = 557 pg/m
    OC = 269 pg/m3
    NO = 45 ppm
    N02 = 4 ppm
    CO = 30 ppm
    THV = 2 ppm
    
    HWS:
    EC = 43 pg/m3
    OC = 908 pg/m3
    NO or N02 = 0 ppm
    00= 13 ppm
    THV = 3 ppm
    Particle Size: DE: 0.14 ±1.8
    pm; HWS: 0.36 ±2.1 pm
    
    
    GEE (2 1996 General Motors
    4.3-L V6 gasoline engines;
    conventional Chevron Phillips
    gasoline, U.S. average
    composition) (CO, NO, N02,
    S02, THC) (PM2 5 composition-
    EC, OC, S04, NH4, N03)
    
    Exposure
    Route: Whole-body Inhalation
    Dose/Concentration: 30, 100, 300, 1000 pg/m3
    TPM
    Time to Analysis: 6 h/day, 7 days/wk for 6 mo. 1
    day post-exposure
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Route: Nose-only Inhalation
    Dose/Concentration: GEE: 60 pg/m3, SDCAs:
    317-1072 pg/m3, RD: 306-954 pg/m3; GEE: 00-
    104 ppm, NO- 16.7 ppm, N02- 1.1 ppm, S02-
    LOppm, THC- 12 ppm; SDCAs: CO- <1 ppm, NO-
    0.19-0.62 ppm, N02- 0.10-0.37 ppm, S02- 0.07-
    0.24 ppm, THC- <1 ppm
    Effects
    Particle Characteristics: Major differences K:
    HWS»DE; Ca DE»HWS; Zn: DE»HWS.
    BALF Cells: No effects were observed except for an
    increase in macrophages at 30 pg/m3 for HWS males
    exposed to HWS.
    
    Cytokines: IL-1 13 was unaffected by DE or HWS. MIP-
    2 decreased for both genders at 1000 HWS. TNF-a
    decreased in females with DE exposure. No TNF-a
    effects for HWS were observed.
    BAL Inflammatory/Injury Markers: LDH was
    unaffected by DE. Exposure to HWS induced an
    increase for males only at 100 and 300 but not at 1000
    pg/m3. Protein was unaffected by DE. HWS exposure
    showed male-only effects at 100 and 300 pg/m3 but not
    at 1000. AP was unaffected by DE or HWS except for
    slight decline induced by HWS at 1000 pg/m3 for both
    genders.
    Other: |3-glucose was unaffected by DE. HWS-
    exposed females showed decreased (3-glucose at 100
    and 300 but not at 1000 pg/m3.
    BALF GSH to (GSH+GSSG): No effects for DE were
    observed. HWS significantly decreased the ratio in both
    males and females at 1000 pg/m3. The effect for
    females was greater than the male effect.
    GEE produced CL in the lungs, heart, and liver. RD
    produced a significant effect in the heart at the low
    dose. SDCAs had no effect on CL. GEE did not affect
    the amount of macrophages or PMN. SDCAs increased
    macrophages. The RD low dose increased
    macrophages and PMN. SDCAs increased Penh
    values and tidal volumes.
    
    Age: 10-12 wk
    
    Weight: 250-300 g
                       Simulated downwind coal
                       emission atmospheres (SDCAs]
                       (fly ash, gas-phase pollutants,
                       sulfate aerosols, NO, N02, S02)
    
                       Paved Road Dust (RD) (Los
                       Angeles, CA; New York City, NY;
                       Atlanta, GA)
    
                       Particle Size: GEE: MMAD-150
                       nm, RD: 2.6 ± 1.7pm, SDCA:
                       0.1-1.Opm
    Time to Analysis: 6 h exposure, immediately
    post-exposure
    Reference: Singh et  A-DEP (4cyl light duty 2.7I Isuzu  Route: Oropharyngeal Aspiration
    al. (2004, 0874721    diesel at 6 kg/m)
                                                    Dose/Concentration: 25 or 100 pg/mouse
                       DEP: SRM 2975               T    L  „   ,  .    .  ,   t ^
    Species- Mouse                                  Tin* to Analysis: single, 4 h
                       Particle Size: A-DEP >50 pm
    Gender: Female                                  (18 h post-exposure measurements taken  but NR
                                                    due to similar results)
    Strain: CD-1
    
    Age: 6-8 wk
                                                                                                Particle Characteristics: DEP had 60% EC vs 9% in
                                                                                                A-DEP. A-DEP had 50% OC vs 5% in DEP.
                                                                                                Phenanthrene and Fluoranthene fractions were much
                                                                                                more prevalent in PAH from DEP than A-DEP.
    
                                                                                                BALF Cells: PMNs significantly increased dose-
                                                                                                dependently with DEP and remained elevated at 18h.
                                                                                                Endotoxin induced the greatest increases of PMNs.
                                                                                                Macrophages increased with A-DEP and were
                                                                                                unaffected by DEP.
    
                                                                                                Cytokines: Endotoxin induced massive responses for
                                                                                                IL-6, MIP-2 and TNF-a but no response from IL-5. A-
                                                                                                DEP increased all 4 cytokines but only at the 100 pg
                                                                                                dose level. Similarly, DEP only increased IL-6 at the
                                                                                                100 pg dose level.
    
                                                                                                BAL Inflammatory/Injury Markers: Microalbumin
                                                                                                increased for both pollutants except DEP induced
                                                                                                increases only at 100 pg. Endotoxin increased microal-
                                                                                                bumin. NAG increased with 100 pg A-DEP.
    December  2009
                                                                      D-107
    

    -------
        Reference
                                 Pollutant
                     Exposure
                        Effects
    Reference: Smith et  CAPs
    al. (2003, 0421071
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 11-12 wk
                        (Fresno, CA)
    
                        Particle Size: <2. 5pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: 6 exp in 2 sets of 3:
    
    Fall! = 847 pg/m3
    Fall2 = 260 pg/m3
    FallS = 369 pg/m3
    Winterl = 815 pg/m3
    Wmter2 = 190 pg/m3
    Winters = 371 pg/m3
    
    Time to Analysis: 4 h/days for 3 consecutive
    days. Parameters measured immediately following
    last exposure.
    Particle Characteristics: Nitrate showed the highest
    variability near 10 fold, followed by Si, S and EC. OC
    concentration was relatively consistent.  Metals
    otherwise appeared proportionate to the
    concentrations.
    
    BALF Cells: Total cells increased at wkl Percent of
    macrophages reduced in wk2 with CAPs.  Number of
    neutrophils increased with CAPs, but only achieved
    statistical significance during wk1 of the fall and winter.
    Lymphocytes increased but were not statistically
    significant.
    
    BAL cell permeability: Upon CAPs exposure, the
    proportion of nonviable cells were increased up to
    242% when compared to controls. The fall of wk2
    induced the highest significant increases followed by
    fall wkl fall wk3, and winter wk3.
    Reference: Smith et
    al. (2006, 1108641
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 8 wk
    
    Weight: 260-270 g
                       CFA: Coal Fly Ash (400 MW,
                       Wasatch Plateau, Utah)
                       (aerodynamic separation)
    
                       Particle Size: 0.4-2.5 pm
    Route: Nose-only Inhalation
    
    Dose/Concentration: 1400 pg/m3 PM25 including
    600 pg/m3 PM,
    
    Time to Analysis: 4 h/days for 3 consecutive
    days. Parameters measured 18 or 36 h post-
    exposure.
    BALF Cells: Percent and total number of neutrophils in
    BALF and blood increased significantly at both 18 and
    36 h. Percent of macrophages decreased slightly while
    number of macrophages increased in bronchiole-
    alveolar duct regions at both time periods.
    
    Cytokines: MIP-2 and transferrin increased at 18 h. IL-
    1|3 increased at 36 h.
    
    Other: Gamma glutamyl transferase decreased at
    36 h. Lung antioxidant increased at 18 h.
    Reference: Song et
    al. (2008, 1560931
    
    Species: Mouse,
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 5-6 wk
                        DEP collected from a 4JB1-type,
                        light-duty (2740 cc), four-cylinder
                        diesel engine operated using
                        standard diesel fuel at speeds of
                        1500 rpm under a load of 10
                        torque.
    
                        Particle Size: 0.4 pm (mean
                        diameter)
    Route: Intranasal Instillation (days 1-5), Whole-
    body Inhalation (days 6-8)
    
    Dose/Concentration: 0.6 mg/mL in 50 pL of saline
    (days 1-5), 6mg/m3 for 1 h/day for 3 days (days 6-
    Time to Analysis: Enhanced Pause (Penh),
    measured on day 9. BAL and lung tissues
    collected  on day 10.
    Airway Hyperresponsiveness: Intranasal exposure
    plus aerosolized DEP caused a significant increase in
    methacholine-induced Penh over the control.
    
    BAL Analysis: There was no significant increase in
    IFN-y in the BAL fluid following DEP treatment but
    there was a significant increase in IL-4 levels compared
    to the control. (IL-4 increase could indicate that DEP
    modulates Th-2 cytokines in the mouse model). DEP
    also induced an increase in total neutrophils and
    lymphocytes in the BAL when compared to the control.
    The nitrite concentration in BAL (indicating NO
    generation) was significantly greater in the DEP
    exposed group than the control.
    
    Histology: Peribronchial and perivascular infiltrates
    were more common in the group exposed to DEP than
    the control.
    
    Ym1 and Ym2 Expression: (see explanation in
    comments section) Ym1  and Ym2 transcripts were
    upregulated in response to DEP exposure in mice.
    Reference:
    Steerenberg et al.
    (2006, 0882491
    Species: Rat
    
    Strain: Crl/WKY
    Age: 6-8 wk
    Ambient air samples
    PMC, PMF:
    -1: Rome, Italy
    -N: Oslo, Norway
    -PL: Lodz, Poland
    -NL: Amsterdam, Netherlands
    Measured Components: Li, Be,
    Route: IT Instillation
    Dose/Concentration: 1 and 2.5 mg/animal
    Time to Analysis: Single, 24 h
    
    
    
    Particle Characteristics: Concentrations of metals
    were highest in Rome. Amsterdam was noted for high
    Mg and V. Lodz was noted for high Pb, Zn, PAH. More
    of PMC was composed of Fe, Mn, Al, Cr, Cu. More of
    PMF, on the other hand, was composed of Zn, Pb, Ni,
    y
    
    BALF Cells: PMNs increased.
                        B, Na, Mg, Al, K, Ca, Ti, V, Cr,
                        Mn, Fe, Co, Ni, Cu, Zn, As, Se,
                        Sr, Mo, Cd, Sn, Sb, Ba,  Ce, Nd,
                        Sm.Au, Hg, TI, Pb, Bi, U, Si,
                        Endotoxins, Cl, NO-, S04
    
                        Particle Size: PMC: 2.35-8.5
                        pm; PMF: 0.12-2.35 pm
                                                                                                   Cytokines: MIP-2 increased dose-dependently. TNF-a
                                                                                                   also increased.
    
                                                                                                   BAL Inflammatory/Injury Markers: CC16 decreased
                                                                                                   substantially. Crustal material (endotoxin, Na, Cl and
                                                                                                   metals but not Ti, As, Cd, Zn, V, Ni, Se) was positively
                                                                                                   associated with short term CC16. Albumin increased.
    December 2009
                                                                         D-108
    

    -------
       Reference
    Pollutant
    Exposure
    Effects
    Reference: Stinn et
    al. (2005, 0883071
    Species: Rat
    Gender: Male and
    Female
    Strain: Crl: (WIU BR
    Age: 40 days
    DE (generated from 1. 6 LVW
    diesel under USFTP 72)
    CO: 10, 37ppm
    C02: 2170, 6540 ppm
    NO: 7.0, 22.8 ppm
    NOX: 8.6, 28.3 ppm
    S02: 0.83, 3.09 ppm
    NH4: ND
    Measured Major Components:
    NO, S02, 1-nitropyrene, Zi. 50%
    by DE weight is EC.
    Route: Nose-only Inhalation
    Dose/Concentration: 3 and 10 mg/m3
    Time to Analysis: 6 h/day, 7 days/wk for 24 mo; 6
    mo. post-exposure
    Body Weight: Mean weight increased substantially
    during the first few weeks in all groups. Food
    consumption decreased in 1-24 mo but was recovered
    in 24-30 mo. Body weight decreased at 23 mo in all
    categories, but recovered except in high dose males at
    30 mo.
    Organ Weight: Absolute weight of lungs, larynx and
    trachea increased from 0 to 12 to 24 mo and stayed
    elevated at 30 mo: Low
    -------
    Reference
    Reference:
    Sureshkumar et al.
    (2005, 0883061
    Species: Mouse
    
    Gender: Male
    Strain: Swiss
    An-, -in 19 wV
    MQd IU~ I Z Wl\
    Weight: 20-25 g
    
    
    
    Pollutant
    GE: Gasoline Exhaust
    (Honda generator EBK 1200,
    four stroke one cyl)
    Including: S02 = 0.11 mg/m3
    NOX = 0.49 mg/m3
    C0= 18.7 ppm
    Particle Size: GE
    >4|jm = 34.1%
    3-4 pm = 15.8%
    2-3 pm = 15.8%
    1.5-2|jm = 10.6%
    0.5-1. 5pm = 5.3%
    <0.5pm = 18.4%
    Exposure
    Route: Nose-only Inhalation
    Dose/Concentration: 0.635 mg/m3
    Time to Analysis: 15min/day7, 14 or 21 days; ;
    <1 h post-exposure
    
    
    
    
    
    
    
    
    Effects
    BALF Cells: Neutrophils (%) increased at 7, 14 and 21
    days (stable). Total cell count, macrophages and
    eosinophils were unaffected. Leukocytes and
    lymphocytes increased, though not significantly.
    Cytokines: GE caused time-dependent increases in
    TNF-aand IL-6. IL-10and IL-1|3 were unaffected.
    
    BAL Inflammatory/Injury Markers: y-GGT, ALP and
    LDH increased after 2 wk of GE exposure and stayed
    stable at 21 days. Total protein slightly increased on 14
    and 21 days, though these increases were not
    statistically significant.
    
                                                                                                  Histopathology: Minor changes at 7 days, mild edema
                                                                                                  in alveolar region at 14 days and sloughing of epithelial
                                                                                                  cells in bronchiolar region and focal accumulation of
                                                                                                  inflammatory cells in alveolar region at 21 days were
                                                                                                  observed in a time-dependent manner.
    Reference:
    Tesfaigzi et al.
    (2002, 0255751
    
    Species: Rat
    
    Gender: NR
    
    Strain: Brown-
    Norway
    
    Age: 7-8 wk
    
    Weight: 310-330 g
    WS (wood stove- Vogelzang
    Boxwood Stove, Model BX-42E,
    wood-Pinusedulis)(CO, NO,
    NOX, total hydrocarbon)
    
    Particle Size: Smaller size
    fraction: 0.405-0.496 pm, larger
    size fraction: 6.7-11.7 pm
    Route: Whole-body Inhalation
    
    Dose/Concentration: Target concentration (low,
    high exposure): 1,10 mg/m3; CO-15-106.4 ppm,
    NO- 2.2-18.9 ppm, NOX- 2.4-19.7 ppm, total
    hydrocarbon-3.5-13.8 ppm
    
    Time to Analysis: 3 h/day, 5 days/wk, 4 or 12 wk.
    Respiratory Function: Total pulmonary resistance
    increased for exposure groups and was significant for
    the low-exposure group. In exposed groups, forced
    expiratory flows and quasistatic compliance were lower
    and dynamic lung compliance higher, the latter being
    significant for the high-exposure group. For the high-
    exposure group,  vital capacity slightly decreased,
    residual volume slightly increased, and CO-diffusing
    capacity had a slight, significant decrease.
    
    BALF Cells: Macrophages decreased significantly in
    the high-exposure group. Particle-laden macrophages
    increased with concentration. Lymphocytes and
    neutrophils slightly increased in the high-exposure
    group.
    
    Cytokines:  LDH increased slightly and protein levels
    decreased slightly in the high-exposure group.
    Cytokines were below  detectable levels.
    
    Histopathology: WS caused minimal to mild chronic
    inflammation in the epiglottis of the larynx. PAS-positive
    cells increased in the 30 day high-exposure group. AMs
    increased with time and concentration.  Particle-laden
    macrophages were seen after 90 days. AB- and PAS-
    positive epithelial cells increased for the 90 day low
    exposure group.
    Reference: Tin-Tin-
    Wn-Shwe et al.
    (2006, 0884151
    
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age: 7wk
    CB14: Printex 90 (Degussa)      Route: IT Instillation
    CB90: Flammruss101
    (Degussa)
    
    Particle Size: CB14:14 nm
    CB95: 95 nm
    Dose/Concentration: 25, 125, 625 pg/mouse;
    approx. 1, 5, 25 mg/kg
    
    Time to Analysis: 1/wk for 4wk. 4 h post-
    exposure
    Body Weight, Thymus, Spleen, Splenic Cell Count:
    No effects were observed.
    
    BALF Cells: Increased total cell numbers were
    observed for 125, 625 pg CB14 (dose-dependent) and
    625 pg CB95. Total cell count was twice as high for
    CB14 at 125 and 625 pg compared to CB95. AM
    numbers exhibited a dose-dependent response for both
    CB14 and CB95 for all doses except 125 pg. Lympho-
    cyte numbers increased at 125 and 625 pg for CB14
    and 625 pg for CB95. PMN numbers increased at 125
    and 625 pg for CB14 and CB95, but the response was
    greater with CB14. PMN numbers were proportional to
    dose surface area for both PM sizes.
    
    BAL Cytokines: CB14 and CB95 induced dose-
    dependent increases in IL-1J3. TNF-a increased at 125
    and 625 pg dose in CB14 with the 125 dose inducing a
    slightly greater increase. CB14 and CB95 induced
    CCL-3 increases 125 and 625 pg.
    
    Chemokine mRNA in lung and lymph nodes: CCL-3
    mRNA increased for CB14 but not CB95 4 h following
    the last exposure. CCL-2 was unchanged.
    
    Mediastinal lymph nodes: The number of CB-laden
    phagocytes increased  in a dose-dependent manner for
    CB14 and CB95. CB14 had higher numbers at all
    doses compared to CB95.
    December 2009
                                                     D-110
    

    -------
       Reference
             Pollutant
                    Exposure
                       Effects
    Reference: long et
    al. (2006, 0976991
    
    Species: Mouse
    
    Gender: Male
    
    Strain: KP600 CD-1
    
    Weight: 22-26 g
    PM25 (collected from stacked
    filter air sampler in Shanghai,
    China)
    
    Fe: FeS04
    
    Zn: ZnS04
    
    PMF:PM25+FeS04
    
    PMFZ: PM25 + FeS04 + ZnS04
    
    Major Measured Components:
    Fe 26 ppm, Zn 9 ppm, S 61 ppm
    
    Particle Size: PM2 5
    Route: IT Instillation
    
    Dose/Concentration: PM: 25 mg/mL, 1mg/mouse
    
    Fe: 15mg/mL, 0.6 mg/mouse
    
    Zn: 15mg/mL, 0.6 mg/mouse
    
    PMF: PM 25 mg/mL + Fe 15 mg/mL,
    1.6 mg/mouse
    
    PMFZ: PM 25 mg/mL + Fe 15 mg/mL,
    1.6 mg/mouse
    
    Time to Analysis: Instilled twice at 0 and 24 h.
    Parameters measured 24 h following last exposure
    (at 48 h).
    Synchrotron X-ray imaging: PMFZ showed the
    greatest increase in alveolar changes. Fe induced
    more hemorrhagic changes, whereas Zn induced more
    nonuniformity of lung texture. This suggests that Zn
    induces PBMC in a dose-dependent manner which
    releases IL-1, IL-6, TNF-a, and IFN-y.
    
    Histopathology: PMFZ induced the most severe
    changes including serious inflammation/pus in bronchia
    and bronchial epidermal cell hyperplasia. For Fe or
    PMF hemorrhagic changes predominated but were less
    severe than PMFZ.
    Reference:
    Upadhyay et al.
    (2008, 1593451
    Species: Rat
    Gender: Male
    Strain: SH
    Age: 6 mo.
    Weight: NR
    Reference:
    Wallenborn et al.
    (2007, 1561441
    Species: Rat
    
    Gender: Male
    Strain: WKY SH
    and stroke-prone SH
    (SHRSP)
    Age: 12-15 wk
    
    
    
    Ultrafme Carbon Particles
    (UFCP)
    Particle Size: Size- 31 + 0.3 nm,
    MMAD- 46 nm, Surface area
    concentration- 0.1 39 m
    particles/m3, Mass specific
    surface area- 807 m /g
    
    
    PM: precipitator unit power plant
    residual oil combustion
    Particle Size: PM: 3.76 pm
    (bulk) ±2. 15
    
    
    
    
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: 172 pg/m3
    Time to Analysis: 24 h exposure. 4 days
    recovery. Sacrificed 1st or 3rd day of recovery.
    
    
    
    
    Route: IT Instillation
    Dose/Concentration: WKY vs SHRSP: 1.11, 3.33,
    8.33 mg/kg
    
    SH vs SHRSP: 3.33, 8.33 mg/kg
    Time to Analysis: Single, 24 h
    Note: 4 h post-exposure study done on WKY vs
    SHRSP but not published.
    
    
    
    
    Pulmonary Inflammation: UFCP did not cause
    pulmonary inflammation.
    Pulmonary and Cardiac Tissue: HO-1, ET-1, ETA,
    ETB, TF, PAI-1 significantly increased in the lung on
    the 3rd recovery day HO-1 was repressed in the heart,
    but the other markers had slight, nonsignificant
    increases.
    
    
    BALF Cells: A dose-dependent increase in total cells
    and neutrophils was observed. Equal response for all 3
    strains except for SH, for both concentrations was
    observed.
    
    BAL inflammation/Injury Markers: LDH exhibited a
    dose-dependent increase in equal response for all 3
    strains. WKY had higher baseline levels of NAG activity
    but, upon PM exposure, SHRSP induced higher
    increases than WKY. GGT exhibited a dose-dependent
    response for all 3 strains. SHRSP showed the highest
    increase followed by WKY and SH. Protein levels
    increased at the high dose level with SHRSP exhibiting
    the highest increases followed by SH and WKY.
    Albumin levels were inconsistent between experiments.
                                                                                             Oxidative Stress - Lung: (WKY vs SHRSP only): SOD
                                                                                             decreased following increased exposure levels with
                                                                                             SHRSP levels generally higher than WKY. Ferritin
                                                                                             levels declined only in SHRSP.
    
                                                                                             GPx: No action but SHRSP levels were similar to SHR
                                                                                             and, in the WKY vs SHRSP experiment, SHRSP
                                                                                             exhibited  higher activity level than WKY.
    
                                                                                             Ferritin: Equivocal results were observed. Levels
                                                                                             decreased at the high dose for WKY and SHRSP but
                                                                                             increased at medium doses for SH and SHRSP.
    
                                                                                             ICDH: Levels increased for WKY and decreased for
                                                                                             SHRSP.
    Reference: Zinc Sulfate (ZnS04,
    Wallenborn et al. aerosolized)
    (2008, 191171)
    	 Particle Size: NR
    Species: Rat
    Gender: Male
    Strain: Wstar Kyoto
    Age: 13 wk
    Weight: NR
    Route: Nose-only Inhalation
    Dose/Concentration: 9.0 + 2.1 pg/m3, 35 + 8.1
    pg/m3, 123.2 ± 29.6 pg/m3
    Time to Analysis: Exposed 5 h/days, 3 days/wk,
    16wk. Half of the rats used for plasma/serum
    analysis, other half for isolation of cardiac
    mitochondria.
    A trend toward increased BALF protein was seen. No
    pulmonary-related effects were seen.
    December 2009
                                                  D-111
    

    -------
    Reference
    Reference:
    Wegesser and Last
    (2008, 1905061
    Species: Mouse
    fipnripr1 Mfllp
    tjciiuci. iviaic
    Strain: BALB/c
    
    Age:8-10wk
    
    
    
    
    Reference:
    Whitekus etal.
    (2002, 1571421
    Species: Mouse
    Gender: Female
    Strain: BALB/c
    Age: 6-8 wk
    Weight: NR
    Pollutant
    Ambient PM2.5-io
    Collected from San Joaquin
    Valley, CA
    Particle Size: PM10.2 5
    
    
    
    
    
    
    
    
    
    DEP (light-duty, four-cylinder
    engine- 4JB1 type, Isuzu
    Automobile, Japan; standard
    diesel fuel) (extracts)
    Particle Size: 0. 5-4 pm
    
    
    
    Exposure
    Route: IT Instillation
    Dose/Concentration: 25-50 pg/mouse
    Time to Analysis: 3, 6, 18, 24, 48, 72 h post IT
    instiiistion.
    
    
    
    
    
    
    
    
    Route: Inhalation
    Dose/Concentration: 200, 600, 2000 pg/m3
    Time to Analysis: Exposed 1 h/day,10 days.
    Animals receiving OVA had 20 min OVA exposure
    after DEP exposure.
    
    
    
    Effects
    BALF Cells: Increased amount of viable cells found in
    PM-exposed mice with dose-response relationship
    between dose of PM and number of total cells
    recovered in BALF. At 6 h, increased numbers of
    macrophages at both 25 and 50 pg/mouse. Increased
    percentage of neutrophils observed with 50 pg/mouse
    PM only. Furthermore, both macrophages and
    neutrophils increased with longer time period from
    instillation, peaking at 24 h. At 50 pg/mouse, MIP-2
    concentrations increased, peaking at 3 h, though not
    statistically significant and returned to basal levels by
    6 h. Positive correlation observed between MIP-2
    concentration and increased neutrophil counts. No
    correlation found between MIP-2 and macrophages.
    DEP+OVA dose-dependently increased IgEand lgG1,
    being more effective than the OVA-alone treatment.
    This effect was significantly suppressed by thiol
    antioxidants MAC or BUG. DEP+OVA increased
    carbonyl protein and lipid peroxide over OVA. MAC or
    BUG suppressed lipid peroxide and protein oxidation.
    No general markers for inflammation were observed.
    
    
    
    Reference: Wichers  PM (HP-12): inside wall of stack
    et al. (2004, 0556361  of Boston, MA power plant
                        burning #6 oil.
    Species: Rat
                        Particle Size: PM: 3.76 urn +
    Gender: Male        2 15
    
    Strain: SH
    
    Age: 75 days
                                  Route: IT Instillation
    
                                  Dose/Concentration: 0.83, 3.33 or 8.33 mg/kg
    
                                  Time to Analysis: single, 6 h for Whole-body
                                  plethysmographs (WBP) and repeated daily for 4-7
                                  days,
                                  96 or 192 h post-exposure
    
                                  non-WBP animals: single,
                                  24,96,192 h post-exposure
                                                  Tidal Volume: A dose-dependent decrease in tidal
                                                  volume (45 % at high dose) was sustained for 1 day
                                                  with very slow recovery over 7 days.
    
                                                  Breathing Frequency: Dose-dependent increase (100
                                                  % at high dose) with recovery at 7 days was observed.
    
                                                  Minute Ventilation: Small dose-dependent increases
                                                  were observed with a return to normal ventilation in 2
                                                  days.
    
                                                  Penh (enhanced pause): Equivocal results in all
                                                  groups were observed (due to major control variation).
    
                                                  BALF Cells: Dose-dependent increases in  total cells at
                                                  24 h, with declined, but still elevated, levels at 192 h.
                                                  Neutrophils increased significantly (10 fold) at 24 h in
                                                  the mid and high dose groups and showed declined,
                                                  but still elevated, levels at 192 h.  Macrophages slowly
                                                  increased in a dose-dependent manner at 192 h.
    
                                                  BAL Inflammatory/Injury Markers: Protein and
                                                  albumin increased at 24 h, returned to relative basal
                                                  level at 192 h at the mid and high dose levels. NAG
                                                  exhibited dose-dependent increases at 24 h and
                                                  sustained these levels through 192 h.
    Reference: Wichers  PM (HP-12): inside wall of stack
    et al. (2006,1038061  of Boston, MA power plant
                        burning #6 oil.
    Species: Rat
    
    Gender: Male
    
    Strain: SH
    
    Age: 71-73 days
    
    Weight: 255-278 g
    Particle Size: 1.95pm ±3.49
    Route: Whole-body Inhalation
    
    Dose/Concentration: 13 mg/m3
    
    Time to Analysis: Phase 1:1st day, filtered air,
    2nd day, 6 h of PM
    
    Phase II: 1st day filtered air, 4 days of 6 h PM each
    
    Immediate post-exposure
    Body/ Lung Weight: No effects on Phase I rats were
    observed. HP-12 exposure increased body weight, left
    lung, right intercostal, and right diaphragmatic lobes in
    Phase II rats. However, results appeared due to normal
    growth in juvenile rats over 4 days.
    
    Lung lobe to Body Weight Ratio: No effects at 1 or 4
    days were observed.
    
    Deposition calculations: V and Co were used to
    estimate deposition rates (good correlation between
    two metals at R2 = 0.94). Total HP-12 deposition using
    Co was 26 and 99 pg (for 1 day and 4 day
    experiments) and using V was 31  and 116 pg.
    Modeling information estimated HP-12 deposition at
    43% in conducting airways and 57% in alveolar region.
    
    Breathing parameters: No changes were observed for
    1 or 4 days studies except for a possible decrease in
    frequency for the 1 day study.
    December 2009
                                                     D-112
    

    -------
        Reference
             Pollutant
                     Exposure
                        Effects
    Reference: Witten   DEP (heavy-duty Cummins N14  Route: Nose-only Inhalation
    et al. (2005, 0874851  research engine operated at
                       75% throttle)
    Species: Rat
    
    Gender: Female
    
    Strain: F344
    
    Age: 8 wk
    
    Weight: ~175 g
                                 Dose/Concentration: Low- 35.3 ± 4.9 pg/m3,
    Particle Size: 7.234-294.27 nm
    High-632.9 ±47.61
    
    Time to Analysis: Exposed 4 h/day, 5 days/wk,
    3 wk. Pretreated with saline or capsaicin.
    There were no differences for substance P. The low-
    exposure group had significantly less NK1. DEP
    reduced NEP activity. Plasma extraversion dose-
    dependently increased and was greatest in capsaicin
    animals. Respiratory permeability dose-dependently
    increased.  IL-113 was significantly higher for the low-
    exposure group. IL-12 was significantly lower in the
    capsaicin high-exposure group. TNF-a increased in the
    high-exposure group and capsaicin low-exposure
    group. High exposure induced particle-laden AMs in the
    lungs, perivascular cuffing consisting of mononuclear
    cells, alveolar edema and increased mast cell number.
    Neutrophil and eosinophil influx was not seen.
    Reference: Wong et
    al. (2003, 0977071
    
    Species: Rat
    
    Gender: Female
    
    Strain: F344/NH
    
    Age: ~4 wk
    
    Weight: ~175 g
    DEP (Cummins N14 research    Route: Nose-only Inhalation
    engine at 75% throttle) (EC-                                           ,
    34 93-601 67 ug/m3 OC-1  90-   Dose/Concentration: Low- 35.3 ± 4.9 pg/m ,
    11.25 pg/m3, Sulfates 0.94-17.96 High- 669.3 ± 47.6 pg/m
    ng/m', Fe- 3.17-6.44, Cr- 0.68-
    1.31 ng/m3, Mn-0.11-0.22 ng/m3,
    Pb-0.97-1.24 ng/m3)
    
    Particle Size: 7.5-294.3 nm
                                  3 wk. Pretreated with saline or capsaicin.
                                                 DEP dose-dependently increased plasma extraversion,
                                                 which was further increased by capsaicin. In the high-
                                                 exposure group, particle-laden AMs (which were
                                                 reduced by capsaicin), inflammatory cell margination,
                                                 perivascular cuffing with subsequent mononuclear cell
                                                 migration and dispersal, increased mast cells, and
                                                 decreased substance P were all seen. NK-1R was
                                                 downregulated in the low-exposure group and
                                                 upregulated in the capsaicin-pretreated high-exposure
                                                 group. NEP decreased significantly for both groups.
    Reference: Wu et
    al. (2003, 1997491
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 60 days
    Zn2*
    
    Particle Size: NA
    Route: IT Instillation
    
    Dose/Concentration: 50 pm/rat
    
    Time to Analysis: Single, 24 h
    Cells: Decreased number of airway epithelial cells
    shown with PTEN protein immunostaining.
    Macrophages were unaffected.
    Reference:
    Yamamoto et al.
    (2006, 0966711
    
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age: 7 wk
    
    Weight: 23 g
    CB14: Printex 90 (Degussa)     Route: IT Instillation
    CB95:Flammruss101
    (Degussa)
    
    LTA: Lipoteichoic acid
    
    14CLCB14+LTA
    
    95CL: CB95 + LTA
    Dose/Concentration: CB14: 0, 25,125, 625
    pg/mouse
    
    CB95: 0, 25,125, 625 pg/mouse
    
    LTA: 10or50|jg/mouse
    
    14CL: 125 pg CB14 + 10 or 50 pg LTA
    CB14 measured Components: C 95CL: 125 pg CB95 + 10 or 50 pg LTA
    96.79%, HR 0.19%, NO.13%, S
    0.11%, Ash 0.05%, 0 2.74%     Time to Analysis: Single, 4 and 24 h
    
    CB95 measured Components: C
    97.98%, HR 0.15%, N 0.28%, S
    0.46%, Ash 0%, 01.14%
    
    Particle Size: CB14:14 nm;
    CB95: 90 nm
    BALF Cells: CB95 induced dose-dependent increases
    of PMN. CB14 induced an increase in PMNs but the
    increases were not dose-dependent.  LTA massively
    increased PMN. LTA induced dose-dependent
    increases in total cells, especially at high dose at 24 h.
    LTA had massive synergistic effect with CB14 and
    CB95 for total cells and PMNs. Total cell count and
    PMN levels were highest in 14CL with levels at 24 h
    higher than at 4 h. Macrophage data were inconsistent.
    
    Cytokines: CB95 induced dose-dependent  increases
    in IL-6, TNF-a, CCL2 and CCL3. CB14  induced dose-
    dependent increase in CCL2 and CCL3. Exposure
    induced increases of IL-6 at the high dose only. Slight
    effect on TNF-a was observed. LTA induced  dose-
    dependent increases of IL-6, TNF-a and CCL3.14CL
    massively induced IL-6 and CCL2. No combination of
    CB and LTA affected TNF-a or CCL3.
    
    mRNA Expression: LTA, 14CL and 95CL increased
    TLR2 mRNA expression with 95CL and  14CL inducing
    higher increases than LTA. No effect on TLR4 mRNA
    expression was observed.
    December 2009
                                                    D-113
    

    -------
        Reference
             Pollutant
                    Exposure
                        Effects
    Reference:
    
    Yanagisawa et al.
    (2003, 0874871
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6 wk
    
    Weight: 29-33 g
    DEP:
    (4JB1  light duty 4cyc 2, 74 liter
    Isuzu engine)
    
    LPS
    
    DEP-OC: organic compounds
    
    DL: DEP + IPS
    
    DDL: DEP-OC + IPS
    
    Particle Size: 04 |jm
    Route: IT Instillation
    
    Dose/Concentration: DEP/DEP-OC: 125
    pg/mouse
    
    IPS: 75 pg/mouse
    
    Time to Analysis: Single, 24 h
    BALF Cells: DEP and DEP-OC increased neutrophils
    but the increases were not statistically significant. IPS
    increased neutrophils significantly. DL and DDL
    massively increased neutrophils at greater levels than
    IPS alone. Macrophages were unaffected.
    
    Cytokines: IPS increased IL-lp, MIP-1a, MCP-1 and
    KC. DEP and DEP-OC had no effect. DL induced
    further increases. DDL decreased cytokines compared
    to LPS alone. DEP-OC increased IL-lp and  MIP-1a
    mRNA expression slightly. DEP had no effect. LPS
    significantly increased IL-1|3and MIP-1a mRNA
    expression. DL increased expressions while DOL did
    not.
    
    Pulmonary Edema: LPS, DEP and DEP-OC increased
    edema. DL further increased this effect. DOL had no
    effect compared to LPS alone.
    
    Histology: DL elevated neutrophil inflammation
    interstitial edema and alveolar hemorrhages. DOL
    induced neutrophilic inflammation without the alveolar
    hemorrhages.
    
    mRNA Expression of TLRs: DEP-OC, DL,  DOL and
    LPS increased TLR2.  DEP had no effect. All  particles
    increased TLR4 mRNA expression.
    Reference:
    Yokohira et al.
    (2007, 0979761
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344/DuCrj
    
    Age: 10 wk
    DQ-12: Quartz dust (Douche
    Montan)
    
    HT: Hydrotalcite (Kyoward 500,
    PL-1686, KYOWA)
    
    POP: Potassium Octatitanate
    fiber (TISMO, Otsuka)
    
    PdO: Palladium Oxide
    
    CB: Carbon Black (Mitsubishi
    Kasei)
    
    Particle Size: DQ12 <7 pm
    
    HT7.8 ± 1.5pm
    
    POP: <50 urn length; <2 pm
    width
    
    PdO: 0.54 ±1.11  pm
    
    CB: 28 nm
    Route: IT Instillation
    
    Dose/Concentration: 4 mg/rat in 0.2 ml saline
    
    Time to Analysis: Single, 1 and 28 days
    Lung Weight/Body Weight Ratio: DQ-12, HT and
    POP induced increases after 1 day. After 28 days, all
    samples induced increases in lung weight.
    
    BALF Cells: Neutrophils increased significantly in
    walls and alveolar spaces in all groups on 1 day except
    at HT. At 28 days, this increase was maintained only in
    walls with severe and moderate elevations, except for
    DQ-12.
    
    Histopathology: DQ-12 caused pulmonary edema
    both at 1 and 28 days. PdO and CB induced edema at
    28 days. Fibrosis was observed after 28 days with the
    most significant increase, in decreasing order, induced
    by DQ-12, PdO, POP, HT, CB, and the control.
    Histiocyte infiltration was observed after 1 day for DQ-
    12,  POP and PdO. At 28 days, infiltration was observed
    for DQ-12, HT, POP and PdO. Restructuring of alveolar
    walls and microgranulation was observed for all 5
    particles but only at 28 days with DQ 12, PdO, HT,
    POP, CB and control.
    
    Immunohistochemistry: BrdU: At 1  day all 5 particles
    elevated in both area and number. Activity declined
    after 28 days but was still higher than the control.
    
    iNOS: At 1 day DQ-12, POP and PdO induced
    increases. At 28 days, DQ-12 and HT induced in-
    creases.
    
    MMP-3: DQ-12 induced increases at both 1 and 28
     days and PdO at 28 days.
    
    Toxicity scoring: The levels of toxicity are, in
    decreasing order,  as follows: DQ-12,  HT/PdO/POF, and
    CB.
    December  2009
                                                    D-114
    

    -------
        Reference
    Pollutant
    Exposure
    Effects
    Reference: Zhao et  DEP: SRM 2975
    al. (2006, 1009961    DEPE: SRM 1975
    Species: Rat
    
    Strain: SD
    
    Age: NR
    
    Weight: 200 g
                       Particle Size: NR
                        Route: IT Instillation
    
                        Dose/Concentration: 35 mg/kg
    
                        Time to Analysis: Single, 1 day
    
                        AG group coexposed 30 pre and 3, 6, 9 h post
                        DEP/DEPE
                                iNOS Expression in AMs: Both DEP and DEPE
                                increased 12 and 6 fold respectively. NO and
                                peroxynitrite levels increased accordingly. AG had no
                                effect on iNOS expression but AG attenuated NO for
                                both DEP and DEPE but peroxynitrite only for DEPE.
                                DEP induced much higher levels of oxidants than
                                DEPE. Unlike DEPE, DEP was unaffected byAG
    
                                Role of iNOS in Lung Injury: DEP and DEPE induced
                                inflammation (PMN), cellular toxicity (LDH) and lung
                                injury (protein). AG significantly attenuated the DEPE
                                response but no effect was observed on the DEP
                                responses.
    
                                Cytokines: IL-12 levels were induced by both DEPE
                                and DEP, with DEPE inducing higher increases than
                                DEP, and both were significantly attenuated byAG
                                DEP and DEPE induced similar increases in IL-10
                                levels. AG increased DEP effect 3 fold and attenuated
                                DEPE to control.
    
                                CYP Enzymes: DEP and DEPE induced increases in
                                CYP1A1 level and activity. AG attenuated CYP1A1
                                activity for both  DEP and DEPE. CYP2B1 level and
                                activity were slightly decreased by DEP and DEPE. AG
                                had no effect.
    
                                Cytosol Phase II Enzymes: DEPE had no effect; AG
                                treatment increased catalase activity. DEP reduced
                                catalase and GST activities. AG had no effect. Neither
                                DEP, DEPE nor AG affected OR quinone reductase.
    Reference: Zhou et  UFe: Ultrafme Fe particles
    al. (2003, 0879401    „  ^.  ,  „.    ,„
                       Particle Size: 72 nm
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 10-12 wk
                        Route: Whole-body Inhalation
    
                        Dose/Concentration: 57 or 90 pg/m3
                                BALF Cells: No significant changes observed in total
                                cell number, cell viability or cell differentials.
                                                                     Cytokines: Only at the high dose was an increase in
                        Time to Analysis: 6 h/days for 3 days, parameters  |L-1|3 observed. No effect on TNF-a or NF-KB-DNA
                        measured within 2 h post-exposure.               bindjng actjvity was observed.
    
                                                                     BAL Inflammatory/Injury Markers: At the high dose,
                                                                     total protein increased. No significant changes were
                                                                     observed in LDH.
    
                                                                     Intracellular Ferritin: The high dose induced
                                                                     increases. No significant differences were observed
                                                                     between the low dose and control.
    
                                                                     Oxidative stress: Antioxidant level by FRAP value
                                                                     decreased at the high dose. GST (glutathione-S-
                                                                     tranferase) activity increased at the high dose. No
                                                                     effect on intracellular GSH and GSSG (glutathione
                                                                     disulfide) was observed.
    December 2009
                                           D-115
    

    -------
    Table D-4.      Effects related to immunity and  allergy.
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Apicella et al.
    (2006, 0965861
    
    Species: Mouse
    
    Strain: BALB/c
    
    Cell Line: 112D5
    hybridoma
    
    Primary
    Macrophages:
    Peritoneal
    Poly OVA (Ovalbumin on polystyrene
    beads) Soluble OVA
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: PolyOVA and Soluble OVA:
    0.2,1.0or5.0|jg/mL
    
    Time to Analysis: 48 h
    IL-6: Stimulation with PolyOVA higher than
    stimulation with soluble OVA
    
    TNF-a: Stimulation with PolyOVA higher than
    stimulation with soluble OVA.
    
    IL-10: No modifications in levels after PolyOVA
    or soluble OVA stimulation.
    
    Viability of Peritoneal Macrophages:
    Stimulation with PolyOVA led to 33% decrease
    in viability. Stimulation with soluble OVA led to
    24% in viability.
    
    Effects of PolyOVA Stimulated Macrophages:
    Culture supernatants from PolyOVA stimulated
    macrophages had a percentage increase of
    asymmetric IgG; however, the addition of rmlL-6
    at identical concentrations did not induce a
    significant increase. It also decreased the
    proliferation of 112D5 hybridoma.
    Reference:
    Arantes-Costa et
    al. (2008, 1871371
    
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age: 6 wk
    
    Weight: NR
    ROFA (solid waste incinerator powered
    by combustible oil; Sao Paulo, Brazil)
    
    Particle Size: NR
    Route: Intranasal Instillation
    
    Dose/Concentration: 60 pg ROFA in 50 pL saline
    
    Time to Analysis: OVA sensitized days 1 and 14.
    OVA-challenged days 22, 24, 26, and 28.  ROFA
    exposed 1-3 h after OVA challenge or saline.
    Pulmonary responsiveness measured day 30 then
    sacrificed. Lungs removed, fixed for 48  h.
    ROFA increased pulmonary responsiveness and
    decreased ciliated cells in nonsensitized mice,
    which were both further amplified in the
    presence of OVA. ROFA did not affect
    eosinophils, macrophages, chronic
    inflammation, or neutral or acidic mucus.
    Reference: Archer  PM = SRM 1648 (NIST)
    et al. (2004,
    0880971
    Species: Mouse
    
    Strain: BALB/c
    D011.10+/+
    transgenic - ova
    specific receptor
    for OVA peptide
    323-339
    
    Age: 4 wk
    Ti02
    
    Particle Size:
    
    SRM1648:avg1.4|jm
    
    Ti02: avg 0.3 pg (sic)
    Route: Intranasal instillation
    
    Dose/Concentration: 500 pg/30 pi sterile saline,
    initial 0-750 pg range finding
    
    Time to Analysis: Ova challenge at 68 h, Meth-
    acholine aerosolization/AR at 72 h
    Airway responsiveness (WBP): AR induced by
    Ova/Mch challenge was significantly and dose-
    dependently increased at doses of
    SRM1648 >500 pg .  Ti02/0va exposure was not
    significantly different from saline. PM associated
    endotoxin did not contribute to enhanced AR.
    
    Lung inflammation/pathology: No increases
    in BAL macrophages or eosinophils and no
    histological alterations after PM  exposure. Both
    Ti02 and PM increased pulmonary neutrophils,
    indicating particles alone were responsible for
    this increase and that the inflammatory
    response could occur independently of AR.
    Reference: Barrett  HWS (black/white oak)
    et al. (2006,
    1556771
    
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age:8-10wk
    CO
    
    Total Vapor Hydrocarbon (TVH)
    
    Particle Size: 0.25 ±3.3, 0.35 + 2.5,
    0.35 ± 2.0, 0.36 ± 2.1 fjm (MMAD+GSD)
    Route: Whole-body Inhalation
    
    Dose/Concentration: HWS: 30, 100 300,
    1000|jg/m3
    00:0.7,1.6,4.0, 13 ppm
    TVH: 0.3, 0.6, 1.3,3.1 ppm
    
    Time to Analysis:  Pretreatment: ip 10 pg OVA and
    2 mg aluminum hydroxide post-OVA. OVA aerosol
    challenge on day 14, followed by 3 days of HWS.
    Pre-OVA received aerosol OVA challenge on day
    14, then 3 days of HWS on days 26-28 and an
    immediate (second) OVA challenge HWS 6 h/day
    for 3 days. Sacrificed 18 h post-exposure.
    Allergic Inflammation: A statistically significant
    increase in eosinophils was observed at
    300 pg/m3 HWS following OVA challenge as
    compared to OVA alone. No changes in
    macrophages, neurophils and lymphocytes were
    observed. Post-OVA HWS did not significantly
    alter BAL cytokine or serum antibody levels, but
    linear trend analyses indicated decreases in IL-
    2, IL-4, and  IFN-v in the absence of OVA, as
    well as a statistically significant upward trend in
    OVA-specific IgE when HWS exposure followed
    OVA challenge. HWS exposure pre-OVA (prior
    to second OVA challenge) resulted in a
    decrease in  IL-13 (statistically significant at the
    high dose but no evidence of an exposure-
    dependent response), an increase in OVA lgG1
    (trend  significant) and no change in IL-2, IL-4,
    IL-5, IFN-v, OVA IgE, total IgE or OVA lgG2a.
    December 2009
                                                      D-116
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Burchiel et al.
    (2005, 088090)
    Species: Mouse
    Gender: Female
    Strain: A/J
    Age: 12-14 wk
    HWS (black/white oak)
    HWS particle Mass
    BC
    OC
    CO
    Total Vapor Hydrocarbon
    29 other minor components PAH and
    metals
    Particle Size: 0.3 + 3. 0.4 +2.0.4 + 2.
    Route: Inhalation
    Dose/Concentration: HWS: 30, 100, 300,
    1000|jg/m3
    BC:3, 12, 25, 43pg/m3
    CC40, 107, 281,908|jg/m3
    CO: 1,2, 4, 13ppm
    TVH:ND, 1, 1,3ppm
    Time to Analysis: 6 h/day for 6 mo.
    Proliferative Responses: HWS increased
    splenic T cell proliferation at 100 pg/m3 with a
    dose dependent decrease at 300 and
    1000 pg/m exposures (p<0.05) HWS exposure
    did not affect T (CDS), helper! cell (Th, CD4),
    cytotoxic T cell (CTL, CDS), macrophage (Mac-
    1), natural killer cell (NK, CD1 6) cell markers or
    B cell proliferative response to IPS.
                      0.4 + 2|jm(MMAD + GSD)
    Reference:
    Burchiel et al.
    (2004, 0555571
    
    Species: Mouse
    
    Strain: AJ
    
    Age: 10-12 wk
    DE generated alternatively from two
    2000 Cummins ISB Turbo Diesel 5.9 L
    engines using no 2 (chevron) oil and
    15w/40 oil (RotellaT, Shell) run ac-
    cording to USEPA Dynamometer
    Schedule for Heavy-Duty Diesel Engines
    18 PAHs quantified at exposure levels
    (text mentions 65)
    
    Particle Size: NR
    Route: Inhalation
    
    Dose/Concentration: 30,100, 300,1000 mg/m3
    diesel PM
    
    Time to Analysis: 6 h/day, 7 days/wk for 6 mo.
    Proliferative Responses: DE depressed
    splenic T cell proliferation at all exposure levels
    but was not dose-dependent and most
    pronounced at the 30 pg/m3 level. (p<0.05 at all
    levels) Splenic B cell proliferation was increased
    at the 30 pg/m3 level, but not at the other
    exposure levels. Little, if any, PAH was found in
    DE, and the majority of PAH tested in vitro
    enhanced T cell proliferation (below), so PAH is
    likely not responsible for the
    immunosuppressive effect of DE on murine
    spleen cell responses.
    Reference: Chan
    et al. (2006,
    0974681
    
    Species:
    Mouse
    
    Strain: D011.10,
    BALB/c, Nrf2J-
    
    Cell Types:
    Primary bone
    marrow dendritic
    cells and dendritic
    cell line (BC1),T
    cells (BMDC)
    DEP: DE particles
    
    DEP methanol extract:
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: DEP: 10 pg/mL
    
    LPS: 5 ng/mL
    
    Time to Analysis: 24 h
    Dendritic Cell Maturation: Organic DEP
    chemicals interfered in the expression of several
    DC maturation markers. Both DEP and DEP
    extracts were found to inhibit CD86 expression
    and IL-12 production in LPS-exposed DCs, and
    intact particles were not as effective as DEP
    extract. DEP extract treatment of BC1 cells
    reduced their ability to stimulate co-cultured
    antigen-specific T cells, leading to decreased
    IFN-  y and increased IL-10 without affecting IL-4
    or IL-13. DEP extract also induced oxidative
    stress and interfered with DC activation by
    several other Toll-like receptor agonists as well
    as the NF-kB cascade. Inhibition of IL-12
    production by DEP extract was shown to be
    mediated by pro-oxidative chemicals that
    engage the Nrf2 pathway. Taken together the
    inhibition of both IL-12 and IFN-y indicates a
    suppression of the Th1 pathway and provides a
    novel explanation for the adjuvant effect of
    DEPs on allergic inflammation.
    December 2009
                                                       D-117
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Ciencewicki et al.
    (2007, 0965571
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 10-12 wk
    
    Weight: 17-20 g
    DE: generated from a 30-kW(40 hp), 4-
    cylinder Deutz BF4M1008 diesel engine
    
    Influenza A/Bangkok/1/79 (H3N2
    serotype) from Dr. Melinda Beck of the
    University of North Carolina, Chapel Hill
    
    02, CO, N02, NO, S02
    
    02: 20.9-20.5% (Lo, Hi)
    CO: 0.9-5.4 ppm
    N02: 0.25-1.13 ppm
    NO: 2.5-10.8 ppm
    S02: 0.06-0.32  ppm
    H3N2: NR
    
    Particle Size: NR
    Route: Inhalation; Oropharyngeal aspiration (virus)
    
    Dose/Concentration: DE: 529 or 2070 pg/m3
    
    Time to Analysis: 4 h/day for 5 days. Virus
    exposure immediately after last DE exposure.
    Analyzed 18 h post infection.
    DE exposure on susceptibility to Influenza
    Infection: Mice exposed to 0.5 mg/m3 had
    significantly greater levels of HA mRNA
    compared to air-exposed mice. HA levels not
    significantly altered in mice exposed to 2.0
    mg/m3.
    
    DE Exposure on the Influenza-induced
    Inflammatory Response:  f IL-6 mRNA levels
    were significantly greater when exposed to 0.5
    mg/m3 of DE prior to infection compared to air
    exposure. Significantly increased amount of IL-6
    protein observed in exposed mice. Exposure to
    DE in absence of influenza infection had no
    significant effect on IL-6 mRNA or protein levels.
    
    DE Exposure on Pulmonary Injury: Infection
    with the  influenza virus increases levels of PMN
    in BAL fluid. Exposure to either dose of DE prior
    to infection showed no significant effect on PMN
    levels Exposure to DE alone had no effect on
    PMNs in BAL fluid. Neither exposure to DE nor
    infection with influenza significantly increased
    BAL fluid protein levels when compared to non-
    infected, air-exposed.
    
    Other Markers of Injury, NAG and MIA were
    not statistically affected by  DE or influenza
    exposure.
    
    DE Exposure on the Influenza Induced
    Interferon Response: No  significant change in
    TFN-a mRNA levels at either dose of DE,
    although mice exposed to 0.5 mg/m3 of DE prior
    to infection had significantly greater levels of
    IFN-B MRNA compared to  air controls. No effect
    on any of the IFNs observed in uninfected mice
    exposed to DE.
    
    DE Exposure on Surfactant Protein
    Expression: Influenza virus infection alone
    significantly increased expression of SP-A in air-
    exposed. Exposure to 0.5 mg/m3 of DE prior to
    infection had significant decreases in levels of
    SP-A mRNA in the lunas, this effect was not
    observed in 2.0 mg/m DE  exposed. Decrease
    seen in expression of SP-A protein  in lungs of
    mice exposed to 0.5 mg/m3 DE prior to infection.
    Levels of SP-D mRNA and protein were
    significantly decreased in lungs of mice exposed
    to 0.5 mg/m3 of DE prior to infection compared
    with mice exposed to air or 2.0 mg/m3  DE  prior
    to infection. Exposure to 0.5 mg/m  of DE  prior
    to infection with influenza decreased levels of
    SP-D, especially in airways. Mice exposed to
    2.0 mg/m  DE prior to infection showed no
    significant difference.
    Reference: Day et  GEE (General Motors 1996 model 4.3-L
    al. (2008,1902041  V6 engine; regular unleaded fuel) (CO,
                      NO, N02, S02, NH3)
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age:8-10wk
    
    Weight: NR
    Particle Size: NR
    Route: Whole-body Inhalation
    
    Dose/Concentration: Low(L)- 6.6 + 3.7 PM/m3,
    MediumfMl- 30.3 ± 11.8 PM/m3, High(H)- 59.1 ±
    28.3 PM/m , High-Filtered(HF)
    
    Time to Analysis: Pre-OVA protocol: OVA or saline
    sensitized 7 days. OVA challenge day 14. GEE or
    air exposed 6 h/day on days 26-28. Immediately
    after exposure on day 28 challenged with OVA.
    Tested for MCh-induced changes 24 h post-
    exposure then sacrificed. Post-OVA protocol: OVA
    or saline sensitized 7 days. OVA challenge day 14.
    GEE or air exposed days 15-17. Tested for MCh-
    induced changes 24 h post-exposure then
    sacrificed.
    Pre-OVA: In nonsensitized mice, neutrophils
    and IgE decreased in the H group.  IL-2
    increased in the HF group and was dose-
    dependent.  Eosinophils dose-dependently
    decreased.  OVA-specific IgE increased in the H
    group, and OVA-specific lgG2a dose-
    dependently increased. In OVA-sensitized mice,
    OVA-specific lgG1 increased in the M group.
    Airway hyperresponsiveness was lower in the M
    and HF groups.
    
    Post-OVA:  In nonsensitized mice, neutrophils
    dose-dependently decreased, IL-4 decreased in
    the M group, IL-5 decreased  in the HF group,
    and IFN-y decreased at all exposures. In OVA-
    sensitized mice, IL-13 dose-dependently
    decreased.
    December 2009
                                                      D-118
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: de
    Haaretal.  (2005,
    0978721
    
    Species: Mouse
    
    Gender: Female
    
    Strain:
    BALB/cANNCrl
    
    Age: 6-8 wk
    
    Weight: NR
    CBP: Carbon black particles in
    phosphate buffered saline, 1:10 & 1:
    100 dilutions (Brunschwich Chemicals,
    Amsterdam, The Netherlands)
    
    OVA: Ovalbumin
    
    Particle Size: CBP: 30-50 nm
    Route: Intranasal Droplet
    
    Dose/Concentration: CBP+ OVA 200, 20, 2 pg
    (3.3, 0.33, 0.033 mg/ml)
    
    OVA only: 20 pg (0.5 mg/ml)
    
    Time to Analysis: Droplet applied on days 0,1, 2.
    Sacrificed on day 4 or challenged with OVA droplet
    on days 25, 26, & 27. Sacrificed on day 28
    Acute Airway Damage and Inflammation:
    Only day 4 had LDH increased in the 200 pg
    CBP+OVA group. The 200 pg CBP+OVA group
    induced significantly higher numbers of BAL
    cells compared to OVA control. Total protein and
    TNF-a levels were increased only in 200 pg
    CBP+OVA group. RAS, parameter for
    phagocytosis, 200 pg and 20 pg CBP+OVA had
    higher levels than OVA controls.
    
    Adjuvant Activity on PBLN: Total lymphocytes
    in PBLN significantly increased 4-5 fold in the
    200 pg CBP+OVA exposed. 20 pg and 2 pg
    exposures did not increase the number of PBLN
    cells compared to OVA control. All CBP+OVA
    concentrations induced higher levels of IL-4,  IL-
    5, IL-10, and IL-13,  with 200 pg concentration
    having 10-200 times higher levels. IFN-y
    cytokine was increased in the 200 pg dose.
    
    IgE Production: In CBP+OVA, IgEwere
    significantly increased.
    
    PBLN and Lung Lymphocytes after OVA
    Challenge: PBLN cell numbers increased in
    OVA and CBP+OVA sensitized mice. CD4 and
    CDS populations increased in both groups.
    PBLN levels in CBP+OVA and challenged with
    PBS were higher than mice treated with OVA
    and challenged with PBS, both groups cytokine
    production was low, only IL-5 levels were
    significant in the CBP+OVA/PBS group. Higher
    lung lymphocyte numbers were caused by
    higher numbers of CD4 and CD19. Production
    of IL-5 and IL-10 was four to five times higher
    than in OVA treated mice.
    
    OVA Challenge Induces Asthma like Airway
    Inflammation in CBP+OVA Sensitized Mice:
    Total number of cells in BAL increased 10 fold in
    CBP+OVA mice challenged with OVA.
    Eosinophils exhibited highest increase in CBP+
    OVA/OVA group. Perivascular  and peribronchial
    infiltrates and goblet cell hyperplasia in
    CBP+OVA/OVA was confirmed by histological
    examination. Antigen specific inflammation
    induced in CBP+OVA mice.
    December  2009
                                                     D-119
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: de
    Haar (2006,
    1447461
    
    Species: Mouse
    
    Gender: Female
    
    Strain:
    BALB/cANNCr
    
    Age: 6-8 wk
    
    Weight: NR
    CBP: fine (F) and ultrafine (UF) carbon
    black particles (Ken Donaldson Group)
    
    Ti02: fine and ultrafine
    
    OVA: Ovalbumin
    
    Particle Size: F CBP: 260.0 nm
    UF CBP: 14.0 nm
    
    FTi02: 250.0 nm
    UFTi02:29.0nm
    Route: Intranasal Droplet
    
    Dose/Concentration: CBP: 200 pg (3.3 mg/mL)
    
    Ti02: 200 pg (3.3 mg/mL)
    
    OVA: 10 pg
    
    CBP+OVA:200+10|jg
    
    Time to Analysis: Days 0,1,2: Exposed to OVA or
    CBP+OVA. Sacrificed on day 8 & analyzed after 2
    h, or continued to second group.
    Second group: days 25, 26, 27 given OVA
    challenge day 28: sacrificed , analyzed 24 h post
    sacrifice
    Ultrafine Particles Induce Lung
    Inflammation: UF Ti02 and CBP induced a
    local inflammatory response in the airways and
    showed higher levels of LDH and total protein
    as compared to mice exposed to the F particles.
    Cytokine levels were much higher in groups
    exposed to ultrafine particles. Histologic
    analysis of the airways showed that exposure to
    ultrafine Ti02 or CBP leads to peribronchial and
    perivascular inflammatory infiltrates (mostly
    neutrophils). Exposure to OVA alone, or
    combined with fine Ti02 and fine CBP had no
    effects on lung histology.
    
    Ultrafine Stimulate Local Immune
    Responses: Ti02 and CBP particles stimulated
    the local immune response against co
    administered OVA antigen. Fine Ti02 particles
    induced a low but significant increase in PBLN
    cell number. Both types of ultrafine particles
    elicited higher levels of Th-2 associated
    cytokines, with UF CBP stimulating a greater
    response. IFN-y  production was low, but
    significantly higher than OVA exposures.
    
    Ultrafine T\0> Increase OVA-specific IgE and
    lgG1 Levels: Levels of OVA specific IgE were
    significantly increased in animals exposed to the
    UF Ti02+ OVA compared to F Ti02 or OVA-only
    Average IgE level in mice  exposed to ultrafine
    CBP+OVA was not a significant increase. OVA-
    specific lgG2a not detected in any groups.
    
    Ultrafine Particles Stimulate Allergic Airway
    Sensitization Against OVA: At day 28, the
    PBLN cell numbers were significantly higher  in
    both  ultrafine and combination with OVA.
    Production of OVA specific IL-4, IL-5, IL-10and
    IL-13 by PBLN cells was significantly increased
    in both ultrafine Ti02 and CBP. IFN-y levels were
    significantly increased in ultrafine CBP+OVA
    treated animals.  F Ti02  had low, but significant,
    increases in IL-4 and IFN-y compared to OVA
    only.  Allergic airway inflammation and Influxes of
    eosinophils, neutrophils and lymphocytes were
    only found in both groups  exposed to ultrafine
    particles.
    Reference: de
    Haar (2008,
    1871281
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c,
    CD80/CD86-
    deficient, D011.10
    
    Age: 6-8 wk
    
    Weight: NR
    Ultrafine Carbon Black (UFCB)
    (Brunschwich Chemicals; Amsterdam,
    The Netherlands)
    
    Particle Size: Diameter: 30-50 nm
    Route: Intranasal Exposure
    
    Dose/Concentration: 20 |jg/mL
    
    Time to Analysis: Exposed days 1, 2, 3. OVA
    challenge days 25, 26, 27. Spleens and lymph
    nodes from D011.10 mice pooled and CD4+ T-cells
    isolated. Solution injected into tail veins of BALB/c
    mice day 0. CTLA4-lg  ip injected days 0, 2.  PBLN
    cell suspensions plated, restimulated with OVA 4
    day.
    UFCB+OVA induced proliferation of CD4+ T-
    cells, increased cytokine production.
    UFCB+OVA did not induce any effects in
    CD80/CD86-deficient mice. UFCB-induced
    airway inflammation is dose-dependent.
    Reference: de     Ultrafine Carbon Black (UFCB)
    Haar et al. (2008,   (Brunschwich Chemicals; Amsterdam,
    1871281           The Netherlands)
    
    Species: Mouse    Particle Size: Diameter: 30-50 nm
    
    Cell Line: Myeloid
    dendritic cells
    (mDCs)
                                        Route: Cell Culture
    
                                        Dose/Concentration: 25 |jg/mL
    
                                        Time to Analysis: 18 h
                                                  UFCB+OVA increased mDCs in the
                                                  peribronchial lymph nodes, and their
                                                  expressions of CD80, CD86, and MHC-11.
    December 2009
                                                      D-120
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Dong
    et al. (2005,
    0880791
    
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    (BN/CrlBR)
    
    Age: NR
    
    Weight: 200-225 g
    DEP: SRM 2975 (NIST, Gaithersburg,
    MD)
    
    OVA: Ovalbumin
    
    Particle Size: 0.5 pm(MMAD)
    Route: Inhalation
    
    Dose/Concentration: DEP: 20.6 + 2.7 mg/m3
    
    OVA 40.5 +6.3 mg/m3
    
    Time to Analysis: 4 h/dayfor 5 days + OVA 30
    min/day1 xwk on days 8,158,29. Sacrificed on
    days 9 or 30.
    Lung Inflammation/Injury: Both the BAL
    proteins and inflammatory cell counts for DEP
    exposure alone were not different from those of
    the air exposed control, suggesting that DEP
    exposure did not cause lung injury at 9 or 30
    days post-exposure. OVA exposure caused
    significant increases in neutrophils,
    lymphocytes, eosinophils, albumin and LDH
    activity in the lung after two exposures. DEP did
    show a strong  effect on OVA-induced
    inflammatory responses.
    
    Alveolar Macrophage (AM) function: OVA
    exposure resulted in an increase in NO levels in
    the acellular BAL fluid and AM conditioned
    media. This increase was significantly
    attenuated in rats exposed to DEP. DEP
    exposure had no significant effect on the
    production of IL-10 or IL-12 by AM recovered
    from  rats 9 and 30 days post exposure. In
    contrast, OVA sensitization elevated both IL-10
    and IL-12 secretion by AM at both time points.
    
    Lymphocyte population and cytokine
    production: DEP exposure was found to
    increase the numbers of total lymphocytes, T
    cells  and their CD4+ and CD8+ subsets in
    LDLN. OVA exposure also significantly
    increased these cell counts on days 9 and 30.
    DEP+OVA exposure showed a significant
    reduction in total lymphocytes, T cells, CD4+
    and CD8+ subsets on day 30. Levels of IL-4 and
    IFN-y in lymphocyte conditioned media were
    below detection limit of the ELISA kits.
    
    Intracellular GSH levels in AM and
    Lymphocytes: DEP exposure alone slightly
    decrease GSH levels in AM,  but markedly
    reduced GSH concentration in lymphocytes on
    days 9 and 30. OVA exposure significantly
    decreased intracellular GSH in both cell types.
    Combined exposure showed AM and
    lymphocytes to have depleted intracellular GSH.
    
    OVA specific IgE and IgG levels in serum: In
    all samples collected on day 9, both serum IgG
    and IgE levels were under the detection limits.
    On day 30, no measureable IgE levels were
    found. The OVA exposure, however, resulted in
    elevated IgE levels, and was enhanced in rats
    preexposed to DEP. IgE and IgG levels for
    DEP+OVA was twO times higher than OVA alone
    indicating that  DEP has an adjuvant effect on
    the production of IgG and IgE.
    
    Effects of DEP and OVA on Lung iNOS
    expression: AM from various exposure groups
    did not stain for iNOS. 1 rat at day 9 from the
    combined DEP+OVA group showed a slightly
    positive iNOS staining. On day 30, 2 of 5 rats
    from  combined exposure group and 1  from the
    OVA  group showed a positive airway staining.
    December 2009
                                                     D-121
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Dong   DEP: SRM 2975 Diesel Exhaust
    et al. (2005,
    0880831
    
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    (BN/CrlBR)
    
    Age: NR
    
    Weight: 200-225 g
    Particles (NIST)
    
    OVA: Ovalbumin
    
    Particle Size: 0.5 pm(MMAD)
    Route: Nose-only Inhalation
    
    Dose/Concentration: DEP 22.7 + 2.5 mg/m3
    OVA 42.3 +5.7 mg/m3
    
    Time to Analysis: Day 1, 8,15: OVA exposure 30
    min/day
    
    Days 24-28: DEP exposure 4 h/day
    
    Day 29: OVA challenge
    
    Day 30: Whole-body plethysmography
    
    Day 31: Sacrifice
    Effect of DEP on OVA Induced Allergic
    Responses: DEP exposure had a synergistic
    effect with OVA on inducing airway hyper-
    responsiveness (AHR) in rats. DEP alone had
    no effect on IgG production. Levels of OVA-
    specific IgG and IgE increased in OVA+DEP
    exposure. This indicates that DEP pre-exposure
    augments the immune response of rats to OVA
    in the production of allergen specific IgG and
                                                                                      Effect of DEP on OVA Induced Cell
                                                                                      Differentiation: Neither DEP, OVA nor the
                                                                                      combination induced elevated levels of LDH
                                                                                      activity or albumin content, indicating that the
                                                                                      exposure protocols did not cause significant
                                                                                      lung injury.  DEP alone induced moderate but
                                                                                      significant increase of neutrophil numbers. OVA
                                                                                      exposure induced a greater infiltration of
                                                                                      neutrophils than DEP, and infiltration of
                                                                                      eosinophilsand lymphocytes. OVA-induced
                                                                                      eosinophil count markedly increased with DEP
                                                                                      exposure. Total lymphocytes, T cells, and their
                                                                                      CD4+ and CD8+ subsets in LDLN from rats
                                                                                      sensitized and challenged by OVA were
                                                                                      significantly higher than those of air-exposed
                                                                                      non sensitized rats. DEP+OVA exposure
                                                                                      resulted in substantial increase in T cells
                                                                                      compared to OVA alone.
    
                                                                                      Effect of DEP on OVA-induced Oxidant
                                                                                      Generation and GSH Depletion: Exposure to
                                                                                      DEP or OVA alone had no effect on ROS
                                                                                      production by AM. Substantial elevation seen in
                                                                                      ROS for the DEP+OVA exposed group. Both
                                                                                      OVA and DEP exposures resulted in an
                                                                                      increased presence of NO in the acellular BAL
                                                                                      fluid and in AM conditioned media; OVA+DEP
                                                                                      exposure further increased these levels.  The
                                                                                      ATI I cells from OVA exposed rats exhibited a
                                                                                      higher percentage of cells that produce NO and
                                                                                      superoxide than air exposed, non sensitized
                                                                                      rats. DEP and OVA exposure resulted in  a signi-
                                                                                      ficant increase in the percentage of cells that
                                                                                      produce NO and superoxide over the control.
    
                                                                                      iNOS Expression: Immunohistological analysis
                                                                                      in lung tissues showed no AM staining in any
                                                                                      group. Airway epithelium was found to be
                                                                                      positive in all 5 rats from the DEP+OVA group
                                                                                      and 3 of 5 rats from single exposure of DEP or
                                                                                      OVA and 2  of 5 in air only exposed rats. iNOS
                                                                                      expression was significantly higher in ATII cells
                                                                                      isolated from rats exposed to combined DEP
                                                                                      and OVA .
    
                                                                                      GSH levels in AM and lymphocytes: Levels
                                                                                      were slightly lowered by DEP or OVA exposure,
                                                                                      though not statistically significant. DEP+OVA
                                                                                      showed a significant reduction in GSH levels.
    December 2009
                                                      D-122
    

    -------
         Study
                 Pollutant
                                                          Exposure
                     Effects
    Reference: Drela   ASM: Air suspended PM from Upper
    etal. (2006,        -   •  - •    -
    0963521
    Species: Mouse
    Strain: BALB/c
    
    Age: 6 wk
    
    Weight: NR
    Silesia (Poland)
    
    IpgofASM:
    
    Pb(1.136ng)
    
    Cu (0.004 pg)
    
    Co (0.072 ng)
    
    Mn (0.406 ng)
    
    Fe(0.016|jg)
                                         Route: Intraperitoneal Injection
    
                                         Dose/Concentration: 170 mg/kg
    
                                         Time to Analysis: Single, 72 h
                      Cr(0.418ng)
    
                      Ni (0.238 ng)
    
                      Particle Size: 0.3-1 Opm
    CD28 Expression on Thymocytes at Different
    Stages of Development: ASM exposure
    accelerated thymocyte maturation but did not
    alter the expression of CD28 on peripheral CD4
    and CDS T cells isolated from lymph nodes. A
    slight but not statistically significant decrease in
    the expression of CD28 on spleen T cells from
    ASM animals was observed.
    
    Distribution of CD28(low) and CD28(high):
    Acute exposure to ASM resulted in the increase
    of CD28(low) and decrease of CD28 (high)
    thymocyte percentages in the total thymocyte
    population. The percentages of CD28 low and
    high thymocytes did not differ between intact
    and PBS controls. Acute ASM exposure resulted
    in the increase of the percentage of CD28(low)
    and the decrease of CD28(high) thymocytes in
    the CDS low subset. The percentage of CD28
    low and  high positive thymocytes did not differ  in
    CDS high thymocyte subset.
    
    Natural  Regulatory CD4+ CD26+ T Cells in
    the Thymus: The development of thymic
    natural regulatory cells was unaffected by ASM.
    
    Proliferation of Splenocytes and Lymph
    Node Lymphocytes: Decreased proliferative
    responses were evident in splenocytes from
    ASM-exposed animals when cells were
    stimulated with low but not high levels of anti-
    CD3 mAb. In contrast, lymph node lymphocytes
    from ASM treated mice had increased
    proliferative responses independent of anti-CDS
    concentration. Both CD4+ and CD8+ T cells
    from ASM treated mice proliferated more
    vigorously than  from controls. Almost all CD8+  T
    cells from ASM mice were induced to proliferate.
    Reference: Dybing
    et al. (2004,
    0975451
    
    Species: Mouse
    
    Gender: NR
    
    Strain: BALB/cA
    
    Age: NR
    
    Weight: NR
    UP: Urban ambient particles collected in
    5 different sites (Amsterdam, Lodz, Oslo,
    Rome, Dutch seaside) during four-wk
    periods in spring, summer, winter
    seasons from March 2001 to March
    2004.
    
    DEP as reference std: SRM  1650 (NIST)
    
    OVA: Ovalbumin (Sigma Chemical, St.
    Louis, MO)
    
    Particle Size: UP: PM,n and PM, 5
                                         Route: Injection in hind foot pad
    
                                         Dose/Concentration: UP: 100- 200 pg
    
                                         DEP: 50 pg
    
                                         OVA: 50 pg
    
                                         Time to Analysis:
    
                                         DayO: 1 exposure to OVA alone, OVAw/particles,
                                         particles alone.
    
                                         Day 6: Lymph nodes harvested
    
                                         Day 21:1 OVA w/o particles exposure
    
                                         Day 26: Antibody assay
    Allergy Screening: All samples were
    immunostimulatory in the popliteal lymph node
    assay; activity was weak in the absence of OVA
    but statistically significant when injected with
    OVA, indicating an adjuvant effect. Particle
    adjuvancy was further demonstrated via
    significant enhancement of OVA-specific
    antibody responses. All ambient particle
    fractions from all seasons increased IgGl
    Except for a few coarse samples, all fractions
    significantly increased IgE. All fine fractions and
    some coarse fractions significantly increased
    lgG2a,  indicating that most particles could exert
    both Th1 and Th2 adjuvancy. In general, fine
    particles demonstrated stronger adjuvant activity
    than coarse in a pair-wise comparison of coarse
    and fine particles from the same location.
    Reference:
    Dybing, et al.
    (2004, 0975451
    
    Species Rat
    
    Cell Lines: Type 2
    cells, AM
                                         Dose/Concentration: 0-50 |jg/ml
    
                                         Time to Analysis: 20 h
    UP: Urban ambient particles collected in   Route: Cell Culture
    5 different sites (Amsterdam, Lodz, Oslo,
    Rome, Dutch seaside) during four-wk
    periods in spring, summer, winter
    seasons from March 2001 to March
    2004.
    
    DEP: SRM 2975 (NIST)
    
    OVA: Ovalbumin (Sigma Chemical, St.
    Louis, MO)
    
    Particle Size: PM10 and PM2 5
    Inflammation: The coarse fractions were more
    potent than the fine fractions. Among the
    samples, the overall effects of the coarse
    fractions on the cells were dependent on the site
    of collection.  High MIP-2 levels were found
    using particles from some spring collections.
    Coarse particles collected in summer
    demonstrated the highest potency, and samples
    collected during winter proved to be less potent
    but seasonal variation was not obvious for all
    sites. Only minor responses were observed
    using fine fractions from urban sites.
    December 2009
                                                      D-123
    

    -------
         Study
                 Pollutant
                     Exposure
                      Effects
    Reference: Farraj
    et al. (2006,
    1417301
    
    Species: Mouse
    
    Gender: Male
    
    Strain: BALB/c
    
    Age: 6 wk
    
    Weight: NR
    DEP: SRM 2975 NIST
    
    OVA: Ovalbumin
    
    Anti-p75: Rabbit anti-mouse p75
    neurotrophin receptor polyclonal
    antibody (Chemicon, Temecula, CA)
    
    Anti-trkA: anti-mouse trkA NGF receptor
    antibody (Santa Cruz, Santa Cruz, CA)
    
    Particle Size: DEP:  1.47 pm(MMAD),
    2.75 GSD
    Route: Nose-only Inhalation
    
    Dose/Concentration: DEP: 1.78 to 2.18 mg/m3
    
    Anti-p75: 50 \i\
    
    Anti-trkA: 50 pi
    
    OVA injection: 20 pg
    
    MCH:0,16, 32, 64 mg/ml
    
    Time to Analysis: On day 0: ip injection of 20 pg
    OVA
    
    Day 14: intranasal instillation of 50 pi anti-p75 or
    anti-trkA, 1 h after 1st exposure challenged with
    OVA aerosol for 1 h followed by a h exposure to
    DEP
    
    24 h after DEP exposure: MCH challenge
    Airways Responsiveness: No significant
    differences in avg baseline Penh values of any
    treatment groups.
    
    Vehicle sensitized mice: exposure to DEP, anti-
    p75 or anti-trkA had no effect on MCH-induced
    Penh values.
    
    OVA-sensitized DEP-exposed: seen increase of
    Penh values. Administration of anti-p75 or anti-
    trkA to OVA sensitized mice reversed DEP
    induced Penh increases.
    
    Lung  Function in Ventilated Mice: Compared
    to vehicle sensitized mice, central airway
    resistance (Rn) increased 62% in OVA
    sensitized mice was not a significant increase.
    
    OVA-sensitized DEP-exposed mice,  anti-p75
    decreased central airway resistance (Rn) and
    anti-trkA did not significantly alter Rn. though Rn
    response for anti-p75 was significantly less than
    anti-trkA response, Constant phase model
    parameter of tissue elastance not significantly
    affected by any treatments or by increasing
    MCH dose, indicating development of significant
    regional ventilation inhomogeneity during
    bronchoconstriction.
    
    Airway Pathology: OVA-sensitized mice had
    small increases in intraepithelial mucus
    compared to vehicle-sensitized mice. DEP
    exposure did not enhance severity of OVA-
    induced airway pathology. Anti-p75 or anti-trkA
    administration did not influence airway
    morphology.
    
    BAL Cells: Vehicle-sensitized DEP-exposed
    mice had significantly enhanced macrophage
    numbers by 92% compared to air-exposed,
    vehicle-sensitized mice. Anti-p75 or Anti-trkA
    administration significantly suppressed DEP-
    induced macrophage increase to levels similar
    to air-exposed, vehicle-sensitized group. DEP
    co exposure significantly decreased number of
    macrophages in OVA-sensitized mice to control
    levels. Anti-trkA or anti-p75 had no effect in
    OVA-sensitized, DEP-exposed. Eosinophil
    number greater in OVA-sensitized DEP-exposed
    mice than  in vehicle-sensitized air-exposed
    mice.  No significant effects of DEP exposure on
    neutrophils from vehicle- or OVA-sensitized
                                                                                                           Cytokines: IL4: OVA-sensitized DEP-exposed
                                                                                                           had five-fold increase over vehicle-sensitized,
                                                                                                           air-exposed mice and anti-trkA or anti-p75
                                                                                                           significantly inhibited the DEP-induced increase.
    
                                                                                                           IL5, IL13: OVA-sensitized DEP-exposed had no
                                                                                                           significant change. Anti-p75 or anti-trkA
                                                                                                           administration had no significant effect.
    
                                                                                                           Serum IgE: OVA sensitized mice had a 10 fold
                                                                                                           increase in IgE levels for air and DEP exposed
                                                                                                           mice. Anti-p75, anti-trkA treatment did not cause
                                                                                                           significant effects on IgE levels.
    December 2009
                                                       D-124
    

    -------
         Study
                 Pollutant
                                                          Exposure
                     Effects
    Reference: Farraj   DEP: SRM 2975 collected from diesel-
    etal. (2006,               	"	"'
    Species: Mouse
    
    Gender: Male
    
    Strains: C57/BI6
    
    Age: 6 wk
    powered industrial forklift filter (NIST)
    
    OVA: Ovalbumin
    
    Anti-p75: Rabbit anti-mouse p75
    neurotrophin receptor polyclonal
    antibody
                                         Route: Nose-only Inhalation
    
                                         Dose/Concentration: DEP: 0.87 mg/m3
    
                                         MCH:0,16, 32, 64 mg/ml
    
                                         OVA: 20 pg ip
    
                                         Anti-p75: 50 \i\
    Particle Size: 1.47 (MMAD), 2.75 (GSD)  T|me to Ana|ysis: Day Q. OVA in ge| vehic|e] ip
    
                                         Day 14: anti-p75 exposure,  intranasal instillation
    
                                         1 h post anti-p75 exposure,  OVA aerosol challenge
                                         forl h
    
                                         1 h post OVA challenge: DEP exposure for 5 h
    
                                         48  h post DEP exposure: MCH challenge
    Airway Responsiveness: No significant
    differences in average Penh values among any
    vehicle control groups. No significant differences
    in treatment groups in OVA-sensitized mice at
    baseline 0,16, or 32 mg/mL of MCH. At 64
    mg/mL MCH, OVA-sensitized, DEP-exposed
    mice had a 22% increase in  Penh compared to
    vehicle mice, and a 68% increase compared to
    vehicle-sensitized,  air-exposed mice. Instillation
    of anti-p75 inhibited the DEP induced increased
    Penh.
    
    BALF Cells: DEP exposure in vehicle-
    sensitized mice significantly increased
    macrophages by 161 % compared to air-
    exposed, vehicle-sensitized  mice, while OVA-
    sensitized mice had 69% increase. Anti-p75
    administration significantly suppressed DEP-
    induced  macrophage increase in vehicle-
    sensitized mice. No significant effects of DEP
    exposure or anti-p75 treatment in OVA-allergic
                                                                                                        OVA-sensitized air-exposed mice had a several
                                                                                                        hundred fold increase in the number of
                                                                                                        eosinophils. No significant effects of DEP
                                                                                                        exposure or anti-p75 treatment on eosinophils
                                                                                                        from OVA-sensitized mice. OVA-exposure or
                                                                                                        DEP-exposure had no significant effects on
                                                                                                        neutrophil or lymphocyte number.
    
                                                                                                        Cytokines: No significant effects of DEP alone
                                                                                                        orwithOVAonlL-4, IL-5, or IL-13.
    
                                                                                                        Serum IgE: OVA sensitization in the presence
                                                                                                        or absence of DEP or anti-p75 caused at least a
                                                                                                        3 fold increase in IgE levels. No significant
                                                                                                        effects of DEP or anti-p75 treatment on  IgE
                                                                                                        levels.
    Reference:
    Finkelman et al.
    (2004, 0965721
    
    Species: Mouse
    
    Gender: Female
    
    Strains: BALB/c,
    C57BL/6
    
    Age: 2-4 mo
    DEP: 4JB1 type; Isuzu Automobile,
    Tokyo, Japan
    
    Particle Size: 2pm (MMAD)
                                         Route: Groupl: 1 ip injection of 2 mg of DEP.
                                         Group 2: daily ip injections of 2 mg of DEP
    
                                         Dose/Concentration: 2 mg
    
                                         Time to Analysis: 2-96 h
    Serum Cytokines: Mice in group 1
    demonstrated an increase in serum IL-6
    production but no increase in IL-4 or IL-2
    production. IFN-y levels were decreased in
    group 2. TNF production was not affected.
    
    Spleen Cytokines: When injected before IPS,
    DEP had little effect on the LPS-induced TNF-a
    and IL-6 response, but resulted in a minor
    suppression of INF-y and IL-10. DEP LPS-
    induced increase in INF-y mRNA responses in
    spleen cells.  DEP caused a dose related
    suppression of LPS stimulated INF-y. DEP had
    little or no effect on the percentage of NK or
    NKT cells in the spleen and inhibited LPS-
    induced IFN-y production by NK and NKT. DEP
    failed to inhibit the IFN-y response by anti-CD3
    mAb-activated NKT cells. Oxidant activity was
    not responsible for DEP inhibition of LPS-
    induced IFN-y production.
    Reference:
    Fujimaki and
    Kurokawa (2004,
    0965751
    
    Species: Mouse
    
    Gender: Male
    
    Strains: BALB/c
    
    Age: 4 wk
    
    Cell Types:
    Cervical lymph-
    node (CLN) cells
    DE + particles: Comparison of exposure
    to DE including particles and exposure to
    particle-filtered DE
    
    DE: 12.09 +0.15 NOX, 1.99 + 0.02 N02,
    10.02+ 0.12 NO, 0.18+ 0.002 S02 and
    1769.2 +13.2 C02 (all in ppm).
    
    DE gas: 11.93 + 0.13 NOX, 2.93 + 0.06
    N02, 8.91 + 0.09 NO, 0.11 + 0.003 S02
    and 1838.8 + 15.3 C02 (all in  ppm)
    
    Particle Size: 0.4 pm (MMAD)
                                         Route: Whole-body Inhalation
    
                                         Dose/Concentration: Exposure to: 0,1.0 mg/m3 or
                                         1.0 mg/m3 DE gas only (0.04 mg/m3 PM)
    
                                         Time to Analysis: Exposure for 12 h daily for 5 wk.
                                         Days 14 and 35 challenge with sugi basic protein
                                         (SBP), a cedar pollen allergen, intranasally.
                                         Evaluation is 24 and  48 h after final SBP injection.
    CLN Response: Exposure to DE or DE gas did
    not affect B1 lymphocyte subpopulations of
    CLN. Culture supernatants of CLN cells from DE
    exposed/SBP immunized mice showed
    significant increase in MCP-1 at 24 and  48 h.
    Exposure to DE or DE gas significantly
    increased the amount of TARC and MIP-1a in
    CLN cells from SBP-immunized mice at 48 h.
    December 2009
                                                      D-125
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Fujimaki et al.
    (2005, 1564561
    
    Species: Mouse
    
    Gender: Male
    
    Strains: C57BL/6
    
    Age: 4 wk
    DE generated by 4 cyl 2.741 Isuzu diesel
    
    DE gas = DE filtered to remove particles
    
    Composition of Diesel Exhaust: DE
    DEP: 1.01 mg/m3
    1796ppmC02
    12.09ppmNOx
    0.18ppmS02
    
    Composition of filtered DE Gas: DEP:
    0.04 mg/m3
    1839ppmC02
    11.93ppm NOX
    0.11 ppmS02
    
    Sugi Basic Protein (SBP)- allergen
    
    Particle Size: 0.4 pm (average
    diameter)
    Route: Whole-body Inhalation
    
    Dose/Concentration: 1.0 mg DEP/m3 or 1.0 mg
    DEP/m3 DE gas
    
    Time to Analysis: 12 h daily, 5wk. All mice were
    injected IP with 100 pg SBP before exposure to gas
    or DE and again received 50 pg SBP intranasally
    on days 14 and 35. Evaluation is 1 day after final
    SBP-immunization (mice are euthanized and CLN
    and blood samples are collected)
    CLN: Exposure to DE and gas led to a decrease
    in total number of CLN cells and percentage of
    CD4+ and TCR-B levels. Cell proliferation
    response to SBP was higher in gas-exposed
    mice than in the control group. The production
    of MCP-1 increased in CLN cells when
    stimulated with SBP (in vitro) but the difference
    was not significant at 24 and 48 h. SBP-
    stimulated cells in gas-exposed mice showed
    greatly enhanced MIP-1a production at 24 and
    48 h. Exposure to gas increased the amount of
    TARC in the culture supernatants of CLN cells.
    
    Plasma: Exposure to DE or gas significantly
    decreased the anti-SBP lgG1 antibody liters and
    increased the anti-SBP lgG2a antibody liters in
    mouse plasma.
    Reference:        DEP: generated by a 2369-cc diesel
    Fujimoto et al.      engine operated at 1050 rpm and 80%
    (2005, 0965561     load with commercial light oil
    
    Species: Mouse    Particle Size: 0.4 pm (MMAD)
    
    Gender: Female
    1st day of
    pregnancy)
    
    Strains: Sic: IRC
                                        Route: Whole-body Inhalation
    
                                        Dose/Concentration: 0.3,1.0 and 3.0 mg DEP/m3
                                        (Groups 1,2,3)
    
                                        Time to Analysis: Exposure began at 2 days
                                        postcoitum and was continued until 13 days
                                        postcoitum. Exposure time was 12 h daily for 7
                                        days/wk. Pregnant females were sacrificed 14 days
                                        postcoitum.
                                                 mRNA Expression in Placentas: In groups
                                                 exposed to DE, the expression of CYP1A1
                                                 mRNA decreased to undetectable levels during
                                                 placental absorption and INF-y was increased.
                                                 Levels of CYP1A1  mRNA in normal placentas
                                                 from DE-exposed mice were unchanged. mRNA
                                                 levels of inflammatory cytokines IL-2,  IL-5, IL-
                                                 12a, IL-12B and GM-CSF increased in
                                                 placentas of mice exposed to DE.
    Reference: Gao et  ROFA: collected near a power plant in
    al. (2004, 0879501   FL burning low sulfur # 6 oil.
    Species: Human
    
    Cell Line: Lung
    fibroblasts infected
    with Mycoplasma
    fermentans
    (PM from Dusseldorf, volcanic ash for
    Mt. St. Helens, PM from Utah used to
    compare against ROFA in one
    experiment)
    
    NiS04, CuS04, VOS04, Na3V04
    
    Particle Size: NR
    Route: Cell Culture; seeded into 6-well plates (3-
    4.5x105 cells/3 mL/well) or 24-well plates (0.6-
    1xl05 cells/1.0  mL/well)
    
    Dose/Concentration: PM: 3,10, 20, 40, 50 pg/ml
    
    Metallic salts: 2, 20, 200 pM
    
    Time to Analysis: 24, 48h
    Cytokines: ROFA exposure in combination with
    Mycoplasma fermentans infection synergistically
    amplifies the induction of IL-6 production in
    human lung fibroblasts (HLF). PM from the other
    sources has little synergistic effect on IL-6
    release. Exposing HLF cellsto,M. fermentans
    derived macrophage activating lipopeptide-2
    (MALP-2) and ROFA has the same synergistic
    effect as M. fermentans infection and ROFA.
    MALP-2 and ROFA extract have a similar
    synergistic effect that requires more time to
    appear. ROFA contains high levels of V, Ni, Fe
    and Cu. Exposure of HLF to NiS04 alone and
    NiS04 with MALP-2 produced 10 and 50 fold
    increases,  respectively, in IL-6 production.
    Exposure of HLF to CuS04, VOS04 and
    Na3V04, with and without the presence of
    MALP-2, did not produce as dramatic results as
    seen with Ni. The action of NiS04 and MALP-2
    on IL-6 production was found to be dose
    dependent.
    December 2009
                                                      D-126
    

    -------
         Study
                 Pollutant
                                                          Exposure
                                                                    Effects
    Reference: Gavett  PM2 5 from the German cities of Hettstedt Route: Oropharyngeal Aspirations
    etal. (2003,        orZerbst
    0531531
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 7wk
                                         Dose/Concentration: 50-100 |jg
    PM Composition: samples from Hettstedt
    have several-fold higher levels of Zn,     Time to Analysis: Single, 18 h.
    Mg, Pb, Cu and Cd than samples from
    Zerbst.
    Particle Size: PM2
                                         Sensitization Model: Mice were exposed to 50 pg
                                         PM 2 h before being sensitized with 10 pg OVA,
                                         repeated two days later. On day 14 all mice were
                                         challenged with 20 pg OVA.
    
                                         Parameters measured on days 2 and 7 after final
                                         exposure to OVA.
    
                                         Challenge Model: Mice were sensitized IP with 20
                                         fjg OVA or adjuvant only. 14 days later mice were
                                         exposed to 100 pg PM25 followed 2  h later by 20 pg
                                         OVA. Parameters measured on days 2 and 7 after
                                         final exposure to OVA.
                                                  BAL Analysis: Hettstedt PM significantly
                                                  increased BAL protein and NAG levels. Zerbst
                                                  PM did not. Mice exposed to Zerbst had lower
                                                  levels of LDH than control groups. Hettstedt
                                                  exposed mice had increased levels of IL-1B, IL-
                                                  6 and MIP-2 in comparison to control and to
                                                  mice exposed to Zerbst PM.  PM2 5 at a dose of
                                                  100 pg was not found to be toxic, therefore used
                                                  for subsequent studies.
    
                                                  Airway Responsiveness (PenH): In allergic
                                                  mice tested immediately after exposure,
                                                  Hettstedt PM increased PenH 190% compared
                                                  to baseline, Zerbst increased PenH by 120%
                                                  and the Control increased by 44%.:.: Two days
                                                  after OVA challenge, no differences in non-
                                                  allergic mice from either group. In allergic mice,
                                                  Hettstedt PM still caused a significant response
                                                  to Mch responsiveness, Zerbst none. No effects
                                                  on day seven.
    
                                                  IgE Levels: Serum collected on day 2 showed
                                                  antigen-specific  IgE was increased by Hettstedt
                                                  PM25 in both the sensitization and challenge
                                                  phases when compared to the control and
                                                  exposure to Zerbst. Day 7 serum indicated no
                                                  effect.
    
                                                  BALF Cells: In non-allergic mice both Hettstedt
                                                  and Zerbst PM increased neutrophil numbers
                                                  (3-fold; not statistically significant) and in allergic
                                                  mice, only Hettstedt PM significantly increased
                                                  neutrophil count. Eosinophil numbers were
                                                  increased only in allergic mice exposed to
                                                  Hettstedt PM. Lymphocyte numbers were not
                                                  different among groups.
    
                                                  BAL Injury Markers: At 2 days after both
                                                  Hettstedt and Zerbst PM administered in allergic
                                                  mice caused significant increases in protein,
                                                  LDH and NAG compared to the non-allergic
                                                  groups. Both PMs caused an increase in LDH in
                                                  allergic mice compared to the allergic control,
                                                  but only Hettstedt caused an increase NAG in
                                                  allergic mice compared to control. At 7 days no
                                                  effect.
    
                                                  BAL Cytokines: Allergic mice had increased
                                                  levels of IL-4, IL-5 and IL-13 compared to non-
                                                  allergic mice (at  2 days after). IL-5 was
                                                  significantly increased by exposure to either PM
                                                  in allergic mice compared to  non-allergic mice.
                                                  Exposure to either PM caused an increase in
                                                  TNF-a and IFN-y (by 6-8 fold) in allergic mice,
                                                  there was also an increase in these
                                                  inflammatory cytokines in the non-allergic group
                                                  but was not statistically significant. No
                                                  significant effects were observed in animals that
                                                  underwent the sensitization protocol alone for
                                                  any measurement or endpoint.
    Reference: Gowdy
    et al. (2008,
    0972261
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age:-12-14 wk
    
    Weight: 17-20 g
    DEP (30kW (40hp) 4-cylinder Deutz
    BF4M1008 diesel engine, steady state,
    20% full load) (Low dose: 21% 02, 0.4wt
    ratio OC/EC; High dose: 20.7% 02,
    0.4wt ratio OC/EC) (CO, NOX, S02)
    
    Particle Size: Diameter: -240 nm
    Route: Inhalation
    
    Dose/Concentration: Low- 514 + 3 pg/m3, High-
    2026 + 38 pg/m3
    
    Time to Analysis: 4 h/day, 1 or 5 days
    (consecutive). Necropsied immediately or 18 h
    postexposure.
                                                                                       BAL Analysis: Neutrophils and lung injury
                                                                                       dose-dependently increased. ICAM-1 increased
                                                                                       immediately after both exposures and after 18h
                                                                                       postexposure in the low dose.
    
                                                                                       Cytokines: After 1 day exposure, IFN-y and
                                                                                       TNF-a increased immediately at both doses and
                                                                                       the high dose, respectively. Immediately after 5
                                                                                       days exposure TNF-a and IFN-y increased at
                                                                                       both concentrations and IL-6 increased at the
                                                                                       low dose. At 18 h postexposure IL-6 and IFN-y
                                                                                       increased at both doses, TNF-a and IL-13
                                                                                       increased at the low dose, and  MIP-2 dose-
                                                                                       dependently increased.
    
                                                                                       CCSP, Surfactants: CCSP decreased. SP-A
                                                                                       and SP-D decreases were only significant after
                                                                                       5 days exposure, 18 h post-exposure.
    December 2009
                                                       D-127
    

    -------
         Study
                 Pollutant
                     Exposure
                      Effects
    Reference:
    Hamada et al.
    (2007, 0912351
    
    Species: Mouse
    
    Gender: Female
    (Pregnant close to
    partruition)
    
    Strain: BALB/c
    ROFA (obtained from a precipitator until
    of a local power plant)
    
    Composition of ROFA (in pg/mL): 341.2
    Ni, 323.4V, 232.2 Zn, 18.3 Co, 15.8 Mn,
    8.4 Ca, 6.7 Cu, 6.1 Sr, 5.0 mg, 0.9 Sb,
    and 0.6 Cd.
    
    Particle Size: NR
    Route: Nebulized ROFA leachate
    
    Dose/Concentration: 50 mg/mL dilution
    
    Time to Analysis: Pregnant mice exposed to
    nebulized ROFA leachate for 30 min/day at days
    14,16 and 18 of pregnancy.
    
    Newborns received a single injection (ip) of OVA (5
    pg)+ alum (1 mg) at day 0 followed by exposure to:
    1. aerosolized OVA days 12,13 and 14 (2-wkold
    protocol)
    OR
    2. aerosolized OVA days 32, 33 and 34 (5 wk old
    protocol)
    
    Analysis 48 h after final allergen exposure
    Susceptibility to Asthma: Exposure of mother
    to PBS aerosols during pregnancy did not result
    in prominent asthma features in young. The
    offspring of the ROFA mothers revealed
    increasing AHR and elevated numbers of
    eosinophils in the BAL fluid. Similar results were
    seen in both the 2-wk and 5-wk old groups.
    
    IgE Levels: Histopathology revealed prominent
    inflammation in the lungs of the ROFA neonates
    and increased allergen-specific IgE and lgG1
    levels in the 5-wk group.
    
    Maternal Influence: Breast milk was not shown
    to be responsible for the increased susceptibility
    to allergy seen in offspring.
    
    IL-4 and IFN-y: IL-4 and IFN-y levels in
    maternal mice showed no difference between
    PBS exposed or ROFA exposed mice. Cultured
    spleen cells from mice born of ROFA-exposed
    mothers showed either increased or similar
    levels of IL-4 and decreased production of IFN-y
    causing an increase in the ratio of IL-4/IFN-y
    indicating greater susceptibility to develop Th2-
    allergic response.
    
    Eosinophils: Exposure of mothers to Ni levels
    similar to those found in ROFA had no
    appreciable effect on BAL eosinophil.
    Reference: Hao et  DEP (4-cylinder diesel engine under a
    al. (2003, 0965651  10-torque load)
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 6-7 wk
                      Particle Size: NR
                                         Route: Nebulization
    
                                         Dose/Concentration: 2 mg DEP m3
    
                                         Time to Analysis: Mild Sensitization- Mice receive
                                         IP OVA alum and are challenge with aerosolized
                                         OVA with and without DEPs.  Mice sacrificed d19.
                                         Postchallenge Model- DEPs are delivered to mice
                                         sensitized by IP OVA and alum.  Mice sacrificed
                                         d23.
    
                                         Transgenic Mice: Mice exposed  to nebulized saline
                                         or DEPs for 1 h daily for 3 days.  Mice sacrificed
                                         day5.
                                                   Mild Sensitization: Exposure of previously OVA
                                                   sensitized mice to aerosolized DEP and OVA did
                                                   not affect OVA-specific IgE production, BAL
                                                   eosinophilia or methacholine-induced AHR.
                                                   Aerosolized particles induced inflammation and
                                                   increased MBP deposition and MBP positive
                                                   eosinophils in the mucosa.
    
                                                   IL-6 Transgenic: Exposure to aerosolized DEP
                                                   did not change BAL cytokine levels, but did
                                                   increase AHR and BAL cell count.
    
                                                   Classic Sensitization, Post-Challenge: Did
                                                   not lead to a discernable increase in OVA-
                                                   induced AHR. DEP treatment was associated
                                                   with increased airway inflammation and mucin
                                                   production in larger and intermediary airways.
    Reference:
    Harkema et al.
    (2004, 0568421
    
    Species: Rat
    
    Gender:  Male
    
    Strain: F344, BN
    
    Age: 10-12 wk
    
    Weight: NR
    CAPs (Detroit; July-Sept. 2000; Harvard
    Ambient Fine Particle Concentrator)
    
    Particle Size: 2.5 pm (diameter)
    Route: Inhalation; IT Instillation.
    
    Dose/Concentration: 4 day concentration: 676 +
    288 pg/m3, 5 day concentration: 313+119 pg/m3,
    July concentration: 16-185 pg/m3, September
    concentration: 81-755 pg/m3; IT Instillation- 200 pL
    (soluble and insoluble)
    
    Time to Analysis: 10 h/day 1, 4, 5 day
    (consecutive); F344 rats sensitized to endotoxin,
    BN rats to OVA. Both groups killed 24 h post-
    exposure.
    The retention of PM in the airways was
    enhanced by allergic serialization. Recovery of
    anthropogenic trace elements was greatest for
    CAPs-exposed rats. Temporal increases in
    these elements were associated with eosinophil
    influx, BAL protein content and increased airway
    mucosubstances. A mild pulmonary neutrophilic
    inflammation was observed  in rats instilled with
    the insoluble fraction but instillation of total,
    soluble or insoluble PM25 in allergic rats did not
    result in differential effects.
    December 2009
                                                       D-128
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Harrod  DEE: Diesel Engine Emissions
    et al. (2003,
    0970461
    
    Species: Mouse
    
    Gender: NR
    
    Strains: C57BL/6
    
    Age:8-10wk
    generated from a 5.9-liter turbo diesel
    engine fueled by Number 2 fuel.
    
    DEE Composition:
    
    NOX: 2.0-43.3 ppm
    
    CO: 0.94-29.0 ppm
    
    S02: 8.3-364.9  ppb
    
    Particle Size: 0.1-0.2 pm(MMAD)
    Route: Whole-body Inhalation
    
    RSV: IT administration
    
    Dose/Concentration: DEE: 38.8 pg/m3 (low level)
    or 10027 pg/m3 (high level)
    
    RSV:100|jl
    
    Time to Analysis: 6 h/day 7 days
    
    After the final 6 h exposure period mice were
    infected with RSV.
    
    Parameters measured 4 days post infection
    Viral Gene Expression: For air+RSV, RSV-F
    gene expression was not apparent but RSV-G
    gene expression was detectable at very low
    levels. In DEE+RSV (for high and  low levels),
    RSV-F and -G were markedly elevated. B-Actin
    mRNA levels not changed in DEE-exposed
    compared to air-treated. DEE+RSV for high and
    low levels show 10- to 20- fold induction of RSV-
    G mRNA levels as compared to air+RSV.
    
    BALF Cells: Uninfected low-level  DEE did not
    induce statistically significant increase in cell
    numbers as compared to air+RSV. High level
    DEE+RSV caused increase as compared to
    air+RSV. Uninfected high-level DEE had
    increase as compared to uninfected  air group.
    For all groups, alveolar macrophages were
    predominant cell type and no substantial
    changes in infiltrating cell populations by
    exposure to DEE were noted.
    
    Lung Inflammation & Airway Epithelial
    Morphology: Lung sections from air- or DEE-
    exposed, uninfected did not exhibit any
    observable change. Low level DEE + RSV had
    increased inflammatory cell infiltration in
    peribronchial regions and loss of normal
    cuboidal appearance of Clara cells as compared
    to air+RSV. High level DEE+RSV had more
    apparent lung-inflammation, especially
    surrounding bronchi and bronchioles, and
    increased appearance of pseudo-stratified,
    columnar epithelial cell morphology and
    apparent airway epithelial cell sloughing as
    compared to low level  DEE+RSV,  indicating
    dose-related increase in lung histopathology to
    RSV infection by prior DEE exposure.
    
    Cytokines: TNF-a and IFN-y were significantly
    increased in RSV-infected mice exposed to low
    or high level DEE and  not increased in RSV-
    infected  mice exposed to air. TNF-a  levels
    elevated to similar levels for low and high level
    DEE+RSV. IFN-y exhibited more dose-related
    increase with higher levels in high level
    DEE+RSV versus low level DEE+RSV.
    
    Mucous Cell Metaplasia: DEE exposure in
    uninfected was not altered. Mucous metaplasia
    was increased in epithelium of RSV-infected
    mice when exposed to DEE in a dose-
    dependent manner. Following high level
    DEE+RSV, mucous staining of airway epithelial
    cells in more distal airways was occasionally
    observed.
    
    CCSP Production in Airway Epithelium: DEE
    alone did not have an effect CCSP-producing
    cells, or  Clara cells, decreased in Low DEE +
    RSV and further decreased in high level
    DEE+RSV in large and terminal airways.
    
    Surfactant Protein B: proSP-B staining post
    RSV alone shows now discernible decrease
    when compared to uninfected. Staining levels in
    alveolar  lung regions decreased when exposed
    to low level DEE+RSV,  and further decreased in
    high level DEE+ RSV. Staining in airway
    epithelium  following high level DEE+RSV
    diminished when compared to RSV alone or low
    level DEE+RSV.
    
    SP-A: In alveolar type II cells and  airway
    epithelial cells for untreated and air +RSV, no
    discernible changes in levels. Prior exposure to
    low or high level DEE decreased SP-A staining
    in alveolar type II cells and airways epithelial
    cells during RSV infection.
    December 2009
                                                      D-129
    

    -------
         Study
                 Pollutant
                                                         Exposure
                     Effects
    Reference: Harrod  DEE (2 2000 model 5.9-1 Cummins ISB  Route: Inhalation
    et al. (2005,
    0881441
    
    Species: Mouse
    
    Gender: Male
    
    Strain: C57B1/6
    
    Age: 10-12 wk
    
    Weight: NR
    turbo diesel engines, No. 2 certification
    diesel fuel)
    
    Particle Size: NR
                                        Dose/Concentration: Low- 30 pg/m3 PM, Mid-
                                        Low- 100 pg/m3 PM, Mid-High- 300 pg/m3 PM,
                                        High-1000|jg/m3PM
    
                                        Time to Analysis: 6 h/d, 7 days/wk, 1 wk or 6 mo.
                                        1 wk exposure repeated on separate occasion.
                                        Immediately after exposure, mice anesthetized, IT
                                        instilled with Pseudomonas aeruginosa.
    Bacterial Clearance: Lung bacterial clearance
    was decreased at all levels after 1wk exposure
    and was concentration-dependent 18h
    postinfection. Bacterial clearance was not
    affected at 6m and bacterial counts were higher.
    
    Inflammation, Particle Deposition: Lung
    inflammation and histopathology were increased
    in all exposure groups postinfection. All
    exposure groups possessed particle-laden
    macrophages. Higher doses had a
    concentration-dependent increase.
    
    Ciliated, Clara Cells, TTF-1: Generally, ciliated
    cells decreased with exposure dose, were more
    discernible in inflamed airways, and higher
    doses caused effects in small distal airways.
    Clara cells decreased equally at all exposures
    and were most notable in the distal airway
    epithelium. TTF-1 decreased postinfection.
    Reference:
    Heidenfelder et al.
    (2009, 1900261
    
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    
    Age: 10-12 wk
    
    Weight: NR
    CAPs (Grand Rapids, Ml; July)
    
    Particle Size: Diameter: 0.1-2.5 pm
                                        Route: Whole-body Inhalation
    
                                        Dose/Concentration: CAPs: 493 + 391 pg/m3; OC:
                                        244 ± 144 pg/m3, EC: 10 ± 4 pg/m3, Sulfate: 79 ±
                                        131 pg/m , Nitrate: 39 + 67 pg/m , Ammonium: 39 +
                                        59 pg/m3; Urban dust (Fe, Al, Ca, Si): 18 + 6 pg/m3
    
                                        Time to Analysis: Sensitized to OVA 3 day.
                                        Challenged with OVA or saline 2wk later for 3 day.
                                        Exposed to CAPs 8h/d, 13d. OVA or saline
                                        challenge 9 day after first challenge. Sacrificed 24 h
                                        after last CAPs exposure.
    CAPs enhanced the effects of OVA by causing
    differential expression in genes primarily
    involved in inflammation and airway remodeling.
    CAPs exposure alone had no effect on gene
    expression. CAPs+OVA also increased IgE,
    mucin glycoprotein, and BALF total protein, and
    caused a more severe bronchopneumonia,
    increased mucus cell metaplasia/hyperplasia
    and mucosubstances.
    Reference:
    Hiramatsu et al.
    (2003, 1558461
    
    Species: Mouse
    
    Gender: Female
    
    Strains: BALB/c
    and C57BL/6
    
    Age: 8 wk
    
    Weight: 17-22 g
    DE -DE (generated by diesel engine and  Route: Inhalation
    diluted with filtered clean air)
    Particle Size: NR
                                                                         ,
                                         Dose/Concentration: Low -0.1 mg/m
                                         High -3 mg/m3
    
                                         Time to Analysis: 7 h/day, 5 days/wk, 1 or 3 mo
    Lung Histopathology: DEP-laden
    macrophages accumulated in the alveoli and
    peribronchial tissues in a dose- and duration-
    dependent manner in both strains. Lymphocytes
    and neutrophils increased in both strains, but
    were greatest in the BALB/c mice.
    
    BALF and Mac-1 Positive Cells: BALT
    formation in DEP-laden AMs was seen at the
    high dose group and was greater in the BALB/c
    mice. Mac-1 positive cells, a marker for
    phagocytic activation of the AMs, was observed
    in the high dose groups of both strains at 1 and
    3 mo, and in the low dose group at 1 mo. in
    BALB/c mice.
    
    Cytokine and iNOS mRNA expression:!
    month of exposure increased TNF-a, IL-12p40,
    IL-4 and IL-10 mRNA in a dose-dependent
    manner. IL-1B and iNOS decreased in a dose-
    dependent manner. IFN-y mRNA expression
    increased in BALB/c mice and decreased in
    C57BL/6 mice. Similar results were seen at 3
    mo, except IL-4 and IFN-y mRNA expression
    decreased in the BALB/c mice. In C57BL/6
    mice, IL-4 and IL-10 mRNA increased at the low
    dose but decreased at the high dose.  NF-KB
    activation occurred after 1 wkand 1 month DE
    exposure and was more prevalent in BALB/c
    mice.
    December 2009
                                                      D-130
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Hiramatsu,  (2005,
    0882851
    
    Species: Mouse
    
    Gender: Female
    
    Strains: BALB/c
    
    Age: 8 wk
    
    Weight: 17-22 g
    DE (generated by diesel engine and
    diluted with filtered clean air.)
    
    Mycobacterial Infection -M.tuberculosis
    (ATCC35812) Kurono strain
    
    Particle Size: NR
    Route: Inhalation
    
    Dose/Concentration: Low-0.1 mg/m3
    High-3mg/m3
    
    Mycobaterial infection: 5 ml (nebulized) of a 106
    colony-forming units (CPU) suspension
    
    Time to Analysis: 7 h/day 5 day/wk, 1, 2 or 6 mo.
    Subset infected on last day of DE exposure. CPU
    evaluation 7 wk postinfection.
    Histopathological Observations: DEP-laden
    AMs and DEPs in the alveoli and peribronchial
    tissues increased in a time-dependent manner.
    DE-exposed mice had a greater number of
    mycobacterial lesions, which were
    disseminated. Lesions in the control mice had
    clear borders and consisted of epithelial cells
    and lymphocytes. Tubercle bacilli and DEPs
    coexisted in AMs. BALT was seen around DEPs
    in the 2 and 6-month exposure groups.
    Inflammation cells increased in a time-
    dependent manner with respect to DE exposure.
    
    Granulomatous Lesions in Lungs: 6-month
    DE-exposed mice had a significantly higher
    amount of gross lesions than the 6-month
    control mice.
    
    Mycobacterial Burden: CPU in lungs were
    increased in DE-exposed animals but only the 6
    month exposure resulted in statistically
    significant increases (a ~4-fold increase over
    control). CPU in spleen were not significantly
    altered by DE exposure.
    
    Cytokines and iNOS mRNA Expression:
    Infected DE-exposed mice had time-dependent
    increases of TNF-a, IL-1B, IL-12p40, IFN-yand
    iNOS mRNAs compared to the infected  control
    mice. IL-12 mRNA expression decreased in
    infected  6-month DE-exposed mice.
    Reference:
    Ichinose, T. et al.
    (2003, 0415251
    
    Species: Mouse
    
    Gender: NR
    
    Strains:
    BALB/cAnN,  ICR,
    C3H/HeN
    
    Age: 6 wk
    
    Weight: NR
    DE: DE generated by 3059cc 4-cylinder
    diesel engine
    
    Der f: Crude extract of D. farinae
    
    Particle Size: 0.4 pm(MMAD)
    Route: Inhalation
    
    Dose/Concentration: 1. Air
    2. DE only: 3.0 mg/m3
    3. Air + Der f: 1 mg Der f
    4. DE 3.0 mg/m3 + 1 mgDerf
    
    Time to Analysis: DE: 12 h/day, 7 days/wk, 8wk
    Der f: 2 wk intervals, 6 wk
    
    Analyzed 3 days after last instillation
    Light Microscopic Observations: DE
    exposure caused the proliferation of nonciliated
    cells and epithelial cell hypertrophy. Soot-
    containing macrophages were found in the
    alveolar tissue spaces. Accumulated
    lymphocytes were present in the peribronchiolar
    lymphoid tissue. Inflammatory cells and soot-
    containing macrophages were found in the
    submucosal layer and the vessel interstitium of
    mice treated with DE+Der f in all strains.
    DE+Der f treated C3H/He mice  had
    desquamated goblet cells.
    
    Eosinophil Infiltration: DE treated C3H/He
    mice had a slight eosinophil infiltration in the
    submucosal layer. DE+Der f treated mice in all
    strains had a slight to moderate eosinophil
    infiltration.
    
    Lymphocyte Accumulation: Lymphocytes
    significantly increased in all strains under the
    DE treatment as compared to the air+saline
    treatment, and further increased under the
    DE+Der f treatment.
    
    Goblet Cell Proliferation:  Little proliferation
    was seen in all strains under the DE treatment.
    DE+Der [caused a significant increase  in
    proliferation compared to air+Derf in  ICR mice,
    but a significant decrease in C3H/He  mice.
    
    Local Cytokine and Chemokine Expression
    in Lung Tissue Supernatant: DE+saline
    significantly increased MIP-1a in all strains.
    MCP-1 also increased but not significantly.
    DE+Der f increased IL-5, RANTES, eotaxin,
    MCP-1 and MIP-1ain all strains as compared
    with air+saline and air+Der f.  IL-5 decreased in
    C3H/He mice treated with DE+Der f compared
    to air+Der f. IL-3 decreased in ICR and C3H/He
    mice compared to air+saline.
    
    Derf-specific Immunoglobulin Production in
    Plasma: Increased production of lgG1 was
    statistically significant in ICR and C3H/He mice
    treated with DE+Der f as compared to air+Der f.
    IgE was low in all strains.
    December 2009
                                                      D-131
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Ichinose et al.
    (2004, 1803671
    
    Species: Mouse
    
    Gender: NR
    
    Strains: BALB/c,
    ICR and C3H/He
    
    Age: 5 wk
    
    Weight: NR
    DEP: 2740cc 4-cylinder engine
    
    D. farinae: crude extract
    
    Particle Size: 0.4 pm(MMAD)
    Route: IT Instillation
    
    Dose/Concentration: 1. D. farinae: 1 pm in PBS
    2. D. farinae + DEP: 1 pg in PBS + 50 pg mg DEP
    
    Time to Analysis: 4 times at 2 wk intervals. Mice
    examined 3 wk after last instillation
    Histological Changes: Mice in all three strains
    treated with DEP+D. farinae had a significant
    recruitment of eosinophils, more proliferation of
    goblet cells, and more eotaxin positive
    macrophages in the alveoli than mice treated
    with D. farinae alone.
    
    Local Cytokine Expression in Lung Tissue
    Supernatant: DEP+D. farinae induced
    significant elevation of IL-5 in ICR and C3H/He
    mice as compared to D. farinae alone.
    Production levels of IL-4 and RANTES did not
    correlate with the manifestations of allergic
    airway inflammation induced by the D. farinae
    treatment with or without DEP.
    
    Cytokine Expression in Plasma: IL-5 in
    C3H/He mice treated with DEP+D. farinae was
    significantly higher than D. farinae alone.
    RANTES was unaffected by the DEP treatment
    in all strains.
    
    D. farinae-specific Immunoglobulin
    Production in Plasma: The adjuvant effect of
    DEP on lgG1 production was observed in all
    three strains, with C3H/H3 being statistically
    significant. The production levels of lgG1
    correlated with the manifestations of
    eosinophilic airway inflammation by both
    treatments. No adjuvant effect on IgE production
    was observed.
    Reference: Inoue   PM-OC: Urban PM, collected for 1
    et al. (2007,
    0967241
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6 wk
    
    Weight: 29-33 g
    month during early summer, 2001 in
    Urawa city Saitama,  Japan
    
    IPS
    
    Particle Size: <2.0|jm
    Route: IT Instillation
    
    Dose/Concentration: Vehicle group: PBS
    PM-OC group: 4 mg/kg of PM-OC
    IPS group: 2.5 mg/kg of IPS
    PM-OC+LPS group: combined administration of
    PM-OC +LPS
    
    Time to Analysis: Single, 24 h
    Effects of PM-OC on LPS Related Lung
    Inflammation: PM-OC alone did not
    significantly increase the infiltration of
    neutrophils, but LPS challenge showed a
    marked increase in the number of neutrophils
    compared with vehicle. Administration of LPS
    combined with PM-OC significantly increased
    the infiltration of neutrophils compared with LPS
    administration alone.
    
    Effects of PM-OC on Histological Changes in
    the Lung: Combined treatment with PM-OC
    and LPS resulted in enhanced neutrophilic
    inflammation.
    
    Effects of PM-OC on Pulmonary Edema
    Related to LPS: LPS group compared with
    vehicle group had a significant increase in lung
    water. The combined administration of PM-OC
    and LPS resulted in further increase in the lung
    water compared with LPS administration alone,
    however it was not statistically significant.
    
    Effects of PM-OC on Protein Expression IL-
    1B,MIP-1a,MCP-1andKC:The
    concentrations of these molecules were below
    the detection limits in the PM-OC group. LPS
    treatment significantly increased the protein
    levels of these molecules compared with the
    vehicle treatment. In the PM-OC + LPS group all
    concentrations, particularly KC, were smaller
    than  in the LPS group.
    December 2009
                                                      D-132
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Inoue
    et al. (2006,
    0909511
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6 wk
    
    Weight: 29-33 g
    Carbon black (14 nm PrinteX 90; PrinteX Route: IT Instillation
    25; Degussa, Dusseldorf, Germany)
    Particle Size: 14 nm - 300 rrn
    56 nm - 45 m2/g
    Dose/Concentration: Vehicle group: PBS at pH7.4
    IPS group: 2.5 mg/kg of IPS in vehicle
    Nanoparticle groups: 4 mg/kg carbon black
    nanoparticles (14 nm or 56 nm) in vehicle
    IPS + nanoparticle group: combined administration
    of carbon black and IPS in vehicle
    
    Time to Analysis: Single, 24 h
    Effects of Nanoparticles: Nanoparticles alone
    increased number of total cells and neutrophils,
    but not statistically significant. IPS exposure
    significantly increased numbers for both groups.
    Nanoparticles and/or IPS enhance pulmonary
    edema.
    
    Histology: Treatment with LPS+14 nm
    nanoparticles markedly enhanced neutrophil
    sequestration into the lung parenchyma
    compared to IPS alone. LPS+56 nm
    nanoparticles did not.
    
    Cytokines:  IL-1B level significantly greater for
    both LPS+ nanoparticles groups. TNF-a was not
    significantly altered among the experimental
    groups.
    
    Chemokines: Challenge with 14 nm
    nanoparticles alone elevated the levels of all
    chemokines without significance except for KC.
    IPS alone and with both nanoparticle groups
    caused significant increases in all chemokines..
    
    Formations of 8-OHdG in Lung: IPS plus
    nanoparticles resulted in intensive expression 8-
    OHdG, strongest in LPS+14 nm nanoparticle
    
    Plasma Coagulatory Changes: PT - no
    change for any group. APTT - some change with
    IPS and IPS + nanoparticle groups, fibrinogen
    level significantly elevated after IPS and for
    LPS+14 nm nanoparticle. APC decrease with
    LPS (significant) and LPS + nanoparticle
    groups. vWF increase with LPS (significant) and
    LPS+14 nm (significant).
    Reference: Inoue
    et al. (2004,
    0879841
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6 wk
    
    Weight: 29-33 g
    DEPs [4JB-1 type light-duty, four-
    cylinder, 2.74 liter Isuzu diesel engine
    (Isuzu Automobile Co., Tokyo Japan)]
    
    Washed DEP and DEP-OC - extracted
    with dichloromethane
    
    Particle Size: NR
    Route: IT instillation
    
    Dose/Concentration: Vehicle group: PBS;
    Washed DEP group: 4mg/kg of DEP; DEP-OC
    group: 4mg/kg of DEP-OQLPS group: 2.5mg/kg of
    LPS; Washed DEP+LPS group: combined
    administration of washed DEP +LPS; DEP-OC+
    LPS group: combined administration of DEP-OC +
    LPS
    
    Time to Analysis: 4 h
    COX-1 mRNA: Slightly elevated in both washed
    DEP and DEP-OC groups, but slightly
    decreased in other groups compared to vehicle
    group.
    
    COX-2 mRNA: Slightly increased with DEP-OC,
    increased with LPS, washed DEP + LPS and
    DEP-OC + LPS groups compared to vehicle.
    COX-2 in the DEP-OC + LPS decreased when
    compared to the LPS only group.
    
    Pulmonary Edema: Washed DEP + LPS group
    showed a synergistic enhancement of
    pulmonary edema and local expression of
    proinflammatory chemokines (MCP-1, MIP-1a,
    KC, IL-1B).
    Reference: Inoue
    et al. (2006,
    0967201
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6-7 wk
    
    Weight: 29-33 g
    Carbon black (PrinteX 90; PrinteX 25;
    Degussa, Dusseldorf, Germany)
    
    Particle Size: 14 nm - 300 m2/g
    56 nm - 45 m /g
    Route: IT instillation
    
    Dose/Concentration: Vehicle group: PBS
    Ovalbumin (OVA) group: 1mg OVA; Nanoparticle
    groups: 50 mg carbon black nanoparticles (14 nm
    or 56 nm);;OVA+ nanoparticle group: combined
    administration of nanoparticles and OVA
    
    Time to Analysis: Vehicle group - weekly for 6wk
    OVA group - biweekly for 6 wk
    Nanoparticle groups - weekly for 6 wk
    OVA+Nanoparticle group (same protocol as OVA
    and Nanoparticle) studied 24 h after last
    administration
    Nanoparticles: Exposure to carbon
    nanoparticles resulted in the lung expression of
    TARC, GM-CSFand MIP-1a. The levels were
    higher in the 14 nm group compared to the
     56 nm group.
    
    OVA: In the presence of OVA, nanoparticles
    enhanced levels of TARC, GM-CSF, MIP-1a, IL-
    2 and IL-10, with the effects seen more
    prominently in the 14 nm particles + OVA group.
    December 2009
                                                     D-133
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Inoue
    et al. (2005,
    0886251
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6-7wk
    
    Weight: 29-33 g
    Carbon black (PrinteX 90; PrinteX 25;
    Degussa, Dusseldorf, Germany)
    
    Particle Size: 14 nm - 300 m2/g
    56 nm - 45 m2/g
    Route: IT Instillation
    
    Dose/Concentration: Vehicle group: PBS;
    Ovalbumin (OVA) group: 1mg OVA; Nanoparticle
    groups: 50mg carbon black nanoparticles (14nm or
    56 nm); OVA+ nanoparticle group: combined
    administration of nanoparticles and OVA
    
    Time to Analysis: Vehicle group - weekly for 6 wk
    OVA group - biweekly for 6 wk
    Nanoparticle groups - weekly for 6 wk
    OVA+Nanoparticle group: same protocol as OVA
    and Nanoparticle studied 24 h after last
    administration
    Nanoparticles + OVA: Nanoparticles given with
    OVA enhanced airway inflammation,
    characterized by increased eosinophils,
    neutrophils, mononuclear cells and goblet cells.
    In addition, nanoparticles + OVA significantly
    increased local expression of IL-4, IL-5, eotaxin,
    IL-13,  RANTES,  MCP-1 and IL-6. The formation
    of 8-OHdG was enhanced by nanoparticles +
    OVA.
    
    14 nm Nanoparticles: All these effects were
    more prominent when 14 nm nanoparticles were
    used. The 14 nm nanoparticle + OVA group
    significantly raised levels of total IgE and
    antigen specific production of lgG1  and IgE.
    Reference: Inoue
    et al. (2006,
    1901421
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6 wk
    
    Weight: 29-33 g
    Whole DE (generated by 4-cylinder,
    3.0591, Isuzu diesel engine, Isuzu
    automobile, Tokyo, Japan)
    
    IPS
    
    Particle Size: 110 nm (peak particle
    size)
    Route: Whole-body Inhalation
    
    Dose/Concentration: 0.3 mgsoot/m3
    1.0mgsoot/m3
    3.0 mg soot/m
    
    LPS:125mg/kg
    
    Time to Analysis: IPS prior to
    12 h exposure to exhaust
    BAL fluid, total cells, neutrophils, protein and
    gene levels (MCP-1 and KC) decreased
    compared to control with IPS,  but were smaller
    with IPS + DE. Results are suggestive that
    short-term exposure to DE does not exacerbate
    LPS-related lung inflammation.
    Reference: Inoue
    et al. (2007,
    0967021
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6 wk
    
    Weight: 29-33 g
    
    Cell Type
    Splenocytes
    DEPs [4JB-1 type light-duty, four-
    cylinder, 2.74 liter Isuzu diesel engine
    (Isuzu Automobile Co., Tokyo Japan)]
    IPS
    
    Particle Size: PM2 5
    Route: Cell Culture (Splenocytes resuspended to
    cell density of 1 xl06/mL and 1000 ml applied into
    each of 12-well plate)
    
    Dose/Concentration: DEP: 100 mg/mL; IPS: 1
    mg/mL; LPS(1 mg/mL) + DEP (1,10 or 100 mg/mL)
    
    Time to Analysis: 72  h
    Cell viability: No effect.
    
    Mononuclear cell response: Incubation with
    DEP alone inhibited basal cytokine production.
    LPS significantly increased protein levels of IFN-
    Y, IL-2, and IL-10 compared to control. DEP
    suppressed the LPS-enhanced protein levels in
    a dose-dependent manner and moderately
    elevated the IL-13 level.
    Reference: Inoue
    et al. (2007,
    1988851
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6-7 wk
    
    Weight: 20-30 g
    Carbon nanoparticles (PrinteX 90,
    PrinteX 25; Dusseldorf, Germany)
    OVA
    
    Particle Size: CB14 = 14 nm, CB56
    = 56nm
    Route: IT Instillation
    
    Dose/Concentration: 50 pg and/or 1 pg OVA in
    PBS
    
    Time to Analysis: 1 */wk for 6 wk; sacrifice 24 h
    after last exposure
    Lung Responsiveness: Respiratory system
    resistance, Newtonian resistance and tissue
    dampening were significantly higher in the
    nanoparticle + OVA groups. Elastance and
    tissue elastance were higher in these groups but
    not significantly so. Compliance was
    significantly lower in the nanoparticle + OVA
    groups compared to the control.
    
    Lung mRNA Level for MucSac: Levels were
    significantly higher in nanoparticle + OVA groups
    compared to the control.
    Reference: Inoue
    et. al. (2007,
    0966921
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 6-7 wk
    
    Weight: 29-34 g
    DEP-OC collected from 4JB1 type, light
    duty, 4 cylinder, 2.74 liter Isuzu diesel
    engine, Isuzu Automobile Company,
    Tokyo, Japan)
    OVA
    
    Particle Size: 0.4 |jm
    Route: IT Instillation
    
    Dose/Concentration: 50 pg and/or 1 pg OVA in
    PBS
    
    Time to Analysis: DEP or DEP-OC w/ or w/o OVA
    initially; OVA or vehicle every 2 wk for 6 wk; DEP
    components or vehicle 1 x/wk for 6 wk; sacrifice
    24 h after last instillation
    Total respiratory system resistance, elastance,
    Newtonian resistance, tissue damping, tissue
    elastance displayed general positive trends and
    were significantly higher in OVA and OVA +
    DEP-OC groups. Compliance displayed a
    general negative trend and was significantly
    lower in the washed DEP + OVA group.
    December 2009
                                                      D-134
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Ito et
    al. (2006, 0883911
    
    Species: Rat
    
    Cell Line: L2 cells
    of alveolar
    epithelial cell type
    II origin
    DEP - generated from 2982-cc common
    rail direct injection diesel engine with
    oxidation catalyst and exhaust gas
    recirculation system.
    
    Particle Size: PM2 5
    Route: Cell Culture
    
    Dose/Concentration: 1*106
    
    1,10or30mg/mL
    
    Time to Analysis: 3 h
    ICAM-1 and LDL Receptor mRNA: Up-
    regulation in a dose-dependent manner.
    Statistically  significant at 30 mg/mL compared to
    control.
    
    HO-1 and PAF Receptor mRNA: Up-regulation
    in dose-dependent manner and statistically
    significant at all doses compared to control.
    
    Correlation Between HO-1 and ICAM-1, LDL,
    and PAF: Significant correlation between HO-1
    and each of these.
    Reference: Jang
    et al. (2005,
    1553131
    
    Species: Mouse
    
    Gender: Female
    
    Strains: BALB/c
    
    Age: 5-6 wk
    DEP -generated from 4JB1 type, light
    duty, four-cylinder diesel engine (Isuzu
    Automobile, Co, Tokyo, Japan)
    
    03 - (generated with Sander Model 50
    ozonizers, Sander, Eltze Germany)
    
    OVA
    
    Particle Size: NR
    Route: Whole-body Inhalation
    
    Dose/Concentration: DEP: 2,000 pg/pL (sic)
    03: 2 ppm (avg 1.98 +  0.08 ppm)
    OVA sensitization: 10 mg
    
    Time to Analysis: OVA sensitization,
    DEP, 03 and OVA Challenge on d21- 23
    Exposed to 03 for 3 h and DEP for 1 h
    AH and BAL measured 1 day after last challenge
    Airway Responsiveness: OVA + 03 + DEP
    exposure group had significantly higher
    methacholine-induce Penh than sham group or
    OVA group.
    
    Total cells, proportion of eosinophils and
    neutrophils: The OVA + 03 + DEP group was
    significantly higher than OVA group and OVA+
    03 group.
    
     \L-4: OVA + 03, OVA + DEP and OVA + 03 +
    DEP IL-4 level increased compare to OVA
    group.
    
    IFN-y: Levels significantly decreased in OVA +
    DEP and OVA + 03 + DEP compared to OVA +
    03.
    Reference:
    Jaspers et al.
    (2005, 0881151
    
    Species: Human
    
    Cell Lines: A549
    cells, primary
    human bronchial
    and nasal epithelial
    cells
    DEas: aqueous-trapped solution of DE
    (emissions from Caterpillar diesel
    engine, model 3304)
    
    Influenza: A/Bangkok/1/79 (H3N2
    serotype)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: Influenza: 3x105 cells
    infected with 320 hemagglutination units (HAU)
    
    DEas: For A549 cells: 6.25,12.5, 25 pg/cm2. For
    bronchial and nasal cells: 22 or 44 pg/cm2.
    
    Time to Analysis: 2  h incubation with DEas then
    virus added.
    
    HA RNA levels analyzed at 0,15, 30, 60 or 120 min
    post infection.
    
    IFN and MxA responses: analyzed 24 h post
    infection.
    
    Fluorescence: some cells treated with GSH-ET 30
    min before DEas exposure. Measured 2 h post-
    influenza infection.
    A649 Cells Increased Susceptibility: DEas
    enhances HA RNA levels in A549 cells in a
    dose-dependent manner. 25 pg/cm2 significantly
    enhanced levels in A549 cells compared to the
    influenza-infected controls. Viral protein levels
    were increased in A549 cells. Exposure to DEas
    increased the number of influenza-infected
    epithelial cells in A549 cells.
    
    Human Nasal and Bronchial Cells
    Susceptibility: Exposure to DEas increased HA
    RNA levels in the nasal and bronchial cells.
    Statistically significant at 22 pg/cm2 for nasal
    cells and approaching significance at 44 pg/cm
    for bronchial cells. Exposure of both types to 44
    pg/cm2 enhanced viral protein levels.
    
    Influenza Induced IFN Response in A649:
    Exposure to DEas does not suppress but
    enhances IFN-B mRNA levels. Treatment
    enhanced influenza-induced nuclear levels of
    both phospho-STAT-1 and  ISFGSg. ISRE-
    promoter activity was enhanced,  but not
    significantly. Treatment enhanced myxovirus
    resistance protein (MxA) mRNA levels. This data
    suggest that DEas exposure enhances influenza
    virus replication without suppressing production
    of IFN-B or IFN-B-inducible genes.
    
    Influenza Induced IFN Response in Human
    Nasal and Bronchial Cells: Exposure to DEas
    increased IFN-B and MxA levels.
    
    Oxidative Stress in A649: DEas exposure
    dose-dependently increases oxidative stress in
    A549 cells within 2-h post-exposure. Add the
    antioxidant GSH-ET and it reverses the effect.
    Pretreatment with GSH-ET A549 cells reversed
    the effects of DEas on the number of influenza-
    infected cells, and reduced HA RNA levels.
    
    Oxidative Stress in Human Bronchial Cells:
    The results were the same  asA549 cells
    pretreated with GSH-ET. Or Pretreatment with
    GSH-ET also reversed effects of DEas on HA
    RNA levels.
    December 2009
                                                      D-135
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Kaan
    and Hegele (2003,
    0957531
    
    Species: Guinea
    pig
    PMio - EHC-93 obtained (Environmental
    Health Canada, Ottawa, ON, Canada)
    
    RSV - Human RSV (long strain/lot!8D)
    (American Tissue Culture Collection,
    Bethesda, MD)
    Gender: Female    Particle Size: PMio (0.35 pm MMAD)
    
    Strain: Cam
    Hartley
    
    Age: 22-29 days
    
    Weight: 250-300 g
    
    Cell Types: AM
    Route: Cell Culture
    
    Dose/Concentration: PM10: 500 pi/well (100 pg/ml
    MEM)
    
    RSV exposure:: 1 ml/well (6x106 pfu/ml MEM)
    
    Groups: PM10+RSV
    RSV+PM,o
    RSV only
    PM10only
    negative control
    
    Time to Analysis: PM10 - 60 min; RSV - 90 min
    
    Parameters measured 24 h post treatment
    Interaction on Phagocytic Ability of AM: Not
    affected by sequential exposure to RSV and
    PMi0. More than 95% of AM exposed to PM,0
    engulfed PM. AM exposed to PMio showed
    significant increase in mean side scatter in
    comparison to negative control and RSV-
    infected AM. No significant difference between
    AM exposed only to PM10 and AM exposed to
    both agents. No significant side mean side
    scatter difference between AM exposed to PM
    only and to both agents.
    
    Interaction on RSV Immunopositivity: PIvl-;
    exposure inhibits. All RSV-treated groups
    showed significantly greater proportion of  RSV-
    immunopositive cells compared with negative
    control. PM10+RSV showed significantly smaller
    proportion of RSV-immunopositive cells
    compared with RSV group. RSV+PMio group
    similar to RSV group.  Proportion of RSV-
    immunopositive AM was influenced by the
    sequence of exposure to RSV and PMio.
    
    Interaction on RSV Replication: PM exposure
    suppressed RSV replication. AM exposed  to
    both agents produced 3 to 9 fold less RSV
    progeny compared with RSV alone group.
    Quantity of RSV progency was not significantly
    affected by the sequence of exposure RSV and
    PMio. Negative control and PMio only did  not
    propagate progeny.
    
    Interaction of RSV Yield: RSV alone group
    produced the highest RSV yield, those exposed
    to both agents, independent of sequence,
    showed a 5-fold decrease.
    
    Cytokine production: RSV infection stimulated
    all three cytokines measure (IL-6, IL-8 and TNF-
    a) compared to negative control. IL-6: PM10
    significantly reduced RSV-induced IL-6
    production. IL-6 was affected by the sequence
    of exposure to PM,o and RSV (PMio+RSV vs.
    RSV+ PM10).  IL-8: PM10 significantly decreases
    RSV-induced IL-8 production and baseline. No
    affect on sequence of exposure. TNF-a:
    production was increased when exposed to
    RSV, PM10 or a combination of both agents. No
    differences among treatments.
    Reference:
    Kleinman et al.
    (2005, 0878801
    
    Species: Mouse
    
    Gender: Male
    
    Strains: BALB/c
    
    Age: 8-19 wk
    
    Weight: NR
    CAPS: fine (F) and ultrafme (UF) using
    VACES system; performed a 2 sites in
    Los Angeles, CA, one 50-m downwind
    and another 150-m downwind from a
    complex of three roadways, State Road
    CA60, Interstate 10, and Interstate 5
    
    F CAPS in 2001 and 2002, UF CAPS in
    2002 only
    
    OVA: Ovalbumin
    
    Particle Size: UF: dp < 150 nm
    F: dps2.5pm
    Route: Whole-body Inhalation
    
    OVA sensitization: nasal instillation
    
    OVA challenge: inhalation
    
    Dose/Concentration: UF at 50 m: 433 pg/m3
    -UFat150m:283|jg/m3
    
    F at 50 m or 150 m: average 400 pg /m3
    
    OVA sensitization: 50 pg/5 pi
    
    OVA challenge: 30 mg/m3
    
    Time to Analysis: CAPS: 4 h/day, 5 days/wk for 2
    wk
    Sensitization: On morning of each exposure
    
    1st Challenge: week after 10 days of treatment
    
    2nd Challenge: one week following 1st challenge
    
    Sacrificed: 24 h after 2nd challenge
    There were significantly higher concentrations of
    IL-5, IgE, lgG1 and eosinophils in mice exposed
    to either CAPS compared to air. Mice exposed
    to CAPS at 50-m downwind showed higher
    levels of IL-5, lgG1, and eosinophils than those
    exposed to CAPS 150-m downwind.
    December  2009
                                                     D-136
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Kleinman et al.
    (2007, 0970821
    
    Species: Mouse
    
    Gender: NR
    
    Strains: BALB/c
    
    Age: 6-8 wk
    CAPS - concentrated fine (F) and
    ultrafine (UF) using VACES system -
    performed a 2 sites in Los Angeles, CA,
    on 50-m downwind and another 150-m
    downwind from State Road CA60 and
    Interstate 5. Fall 2001-summer 2004
    
    OVA
    
    Particle Size: F: PM25; UF: PM0.15
    Route: Whole-body Chamber
    
    Dose/Concentration: 50 m - F: 394 + 94 pg/m3
    50 m - UF: 297 ± 189 pg/m3
    
    150 m - F: 387 ± 68 pg/m3
    150m-UF:213±95|jg/m3
    
    OVA - 50 mg in 5 ml saline
    
    Time to Analysis: 3, 4 h/day, 5 days/wk, 2wk
    OVA the morning of each exposure
    60m Site: higher levels and statistically
    significant concentration curves of IL-5 and lgG1
    in F-CAP mice at the 50 m site.
    
    160m Site: in no cases were responses greater
    than the 50m or control groups.
    
    F vs. UF: The study was not able to differentiate
    between the effects of F PM and UF PM
    exposures.
    Reference: Klein-
    Patel et al. (2006,
    0970921
    
    Species: Cattle
    and Human
    
    Cell Types
    Bovine tracheal
    epithelial cells
    (BTE)andA549
    ROFA
    
    V205, VOS04, Si02 Ti02, Fe2(S04)3,
    NiS04, IPS
    
    Particle Size: 1.95 pm(MMAD)
    Route: Cell Culture
    
    Dose/Concentration: ROFA: 0, 2.5, 5,10,15, 20
    pg/cm2
    
    IPS: 100 ng/mL
    
    V205: 0, 0.15, 0.3, 0.61, 1.25, 2.5, 5, 10, 20 pg/cm2
    
    NiS04  Fe2(S04)3, Ti02, Si02: 0, 1.23, 2.5, 5,  10, 20
    pg/cm
    
    VOS04: 0, 0.145, 0.29, 0.58, 1.16, 2.32 pg/cm2
    
    Time to Analysis: IPS: 0, 6, or 18 h
    ROFA:  0, 2,4,6 h
    V205:0, 0.25, 0.5, 1,2, 4,6, 8h
    NiS04,  Fe2(S04)3, Ti02, Si02, VOS04: 6 h
    ROFA in BTE: ROFA and ROFA leachate
    inhibition of LPS-induced TAP gene expression
    increases with exposure time and dose. Washed
    particles of ROFA at doses 2.5 to 10 mg/cm
    significantly increased inducible TAP
    expression.
    
    Soluble Metals in BTE: V205 inhibition of IPS
    and IL-1|3 induced TAP gene expression
    increases with exposure time and dose. NiS04
    exhibits non-significant dose dependent
    suppression of inducible TAP gene expression.
    Fe2(S04)3, Ti02 and Si02 were found to have no
    effect.
    
    A549: Results with ROFA and V205 in BTE were
    replicated using the A549 cell line and IL-1|3to
    induce  hBD2 gene expression.
    
    Cellular Viability: Was not significantly affected
    in ROFA doses below 20 pg/cm2 and
    V205/VOS04 doses below 2.5 pg/cm2.
    Reference: Koike
    and Kobayashi
    (2005, 0883031
    
    Species: Rat
    
    Gender: Male
    
    Strains: Wstar
    Kyoto
    
    Age:8-10wk
    
    Weight: 280-350 g
    
    Cell Types: AM,
    PBM (peripheral
    blood monocytes),
    T-cells (antigen
    sensitized)
    Whole DEP: Diesel Exhaust Particles
    collected in the dilution tunnel of a diesel
    inhalation facility. (Ratio of organic
    extract to residual particles in the whole
    DEP was 3:1.)
    Organic extract of DEP
    Residual particles of DEP
    OVA: Ovalbumin
    
    Particle Size: NR
    Route: Cell Culture (1 xio6 cells/ml)
    
    Dose/Concentration: Whole DEP: 10, 30, 100
    pg/mL
    
    Organic extract of DEP: 7.5, 22.5, 75 pg/mL
    
    Residual particles:  2.5, 7.5, 25 pg/mL
    
    Time to Analysis: 24 h post exposure
    la Antigen and Costimulatory Molecules:
    Most control AM did not express these
    molecules. Whole DEP did not cause any
    increase in expression level. 20% of control
    PBM expressed la and 10% B7; expression of
    these molecules was significantly increased by
    whole DEP. Organic extract significantly
    increased the expression of la and B7
    molecules on PBM similar to whole DEP.
    Residuals caused no effect. Organic extract-
    induced expression of la antigen in PBM was
    reduced by treatment with MAC.
    
    AP Activity: After exposure to organic extract, T
    cell proliferation was significantly increased by
    the addition of control PBM in a cell number-
    dependent manner. AP activity of PBM was
    increased over control by exposure to 3 pg/mL
    organic extract, although higher concentrations
    suppressed the activity of PBM.
    
    Cytokine Production: Organic extract
    treatment of PBM decrease IFN-y production
    from T-cells stimulated by PBM. No significant
    effect on IL-4 observed.
    
    HO-1 Protein Level: Levels in PBM were
    significantly increased by exposure to whole
    DEP or organic extract. Levels induced by
    organic extract was diminished by MAC
    treatment.
    December 2009
                                                      D-137
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Last et  PM - aerosol of soot and iron oxide
    al. (2004, 0973341   OVA
    Species: Mouse
    
    Gender: NR
    
    Strains: BALB/c
    
    Age: 6 wk
    
    Weight: 16-20 g
    Particle Size: PMni-PM,
    Route: Inhalation
    
    OVA - Intraperitoneal Injections; Aerosol Exposure
    
    Dose/Concentration: PM - 235-256 pg/m3
    
    OVA-10|jg/0.1 ml injection
    
    OVA aerosol -10 ml of 10 mg/mL (1%) solution
    
    Time to Analysis: PM: 4 h/day, 3 days/wk; OVA: 2
    ip injections days 1 and 15. Aerosol on day 28 after
    first ip; 60 min 3x/wk
    2 Wk PM Exposure/4 Wk OVA Aerosol
    Treatment: The OVA alone group had
    significantly more airway collagen than the PM
    alone group. Histology showed significantly
    more collagen in the treatment than the air
    alone group. There was a significantly greater
    amount of goblet cells than the OVA alone
    group.
    
    4 Wk OVA Aerosol/ 2 Wk PM Treatment: The
    OVA treatment had significantly more goblet
    cells than the PM alone group.
    
    6 Wk Concurrent PM and OVA Treatment:
    Significantly more cells were observed in the
    OVA alone group over the treatment. The
    treatment had significantly more lymphocytes
    and significantly less macrophages than groups
    exposed to PM before or after OVA. Histology
    showed significantly more collagen in the
    treatment than the air or PM alone groups. The
    treatment had significantly more goblet cells
    than the OVA alone group.
    Reference: Li et    DEP (2369-cc diesel engine
    al. (2007, 0931561   manufactured by Isuzu Motor, operated
                      at 1050 rpm, 80% load, commercial light
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c,
    C57BL/6
    
    Age: 9 wk
    
    Weight: NR
    oil)
    
    Particle Size: NR
    Route: Inhalation
    
    Dose/Concentration: DEP: 103.1 + 9.2 pg/m3,
    CO: 3.5 + 0.1 ppm, N02: 2.2 + 0.3 ppm, S02:
     O.01 ppm
    
    Time to Analysis: Protocol 1: Exposed 7h/day,
    5days/wk. Sacrificed at day 0, week 1, 4, 8.
    Protocol 2: DE alone or DE+NAC 7h/d, 1-5 days.
    Airway Hyperresponsiveness: Penh values
    increased in BALB/c mice compared to the
    control at day 0, but no significant changes
    occurred after this time. Penh values increased
    in C57BL/6 mice at 1wk compared to the control
    but returned to control levels at 8 wk.
    
    BALF: Compared to the other strain, the total
    number of cells and macrophages increased
    significantly at 1wk in C57BL/6 mice and at 8wk
    in BALB/c mice. Neutrophils, lymphocytes,
    MCP-1, IL-12, IL-10, IL-4, IL-13 increased
    significantly for both strains. No eosinophils
    were found. IL-1 B and IFN-y increased
    significantly in BALB/c mice compared to
    C57BL/6 mice.
    
    HO-1  mRNAand Protein: HO-1  mRNA was
    more marked in BALB/c mice at 1wk and
    C57BL/6 mice at 4 and 8 wk. HO-1  protein
    percentage changes from the control were
    greater in BALB/c mice at 1wk and C57BL/C
    mice at 8 wk.
    
    MAC: NAC inhibited the increased Penh values,
    total number of cells and macrophages in
    C57BL/6 mice at 1 wk and neutrophils and
    lymphocytes in both strains.
    Reference: Li et
    al. (2009, 1904571
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 6-8 wk
    
    Weight: NR
    CAPs (downtown Los Angeles, CA from
    major freeway, traffic mainly passenger
    cars and diesel trucks; Jan. 2007 or
    Sept. 2006)
    
    Ultrafine carbon black (UFCB; used as
    control)
    
    Particle Size: Fine- <2.5 pm (diameter),
    UF-O.15|jm (diameter)
    Route: Intranasal Instillation
    
    Dose/Concentration: 0.5 pg PM in 50 pL
    suspension
    
    Time to Analysis: Day 1 exposed to PM or saline.
    Day 2 exposed to PM+OVA or OVA or saline alone.
    Repeated on days 4, 7, 9. Different experiment:
    NAC ip injected 4 h pre-instillation on days 1, 2, 4,
    7, 9. All animals rested and OVA aerosol
    challenged 30 min on days 21,  22. Sacrificed day
    23.
    UFP alone had no effect on the lung. UFP+OVA
    significantly increased eosinophils, and OVA-
    specific lgG1 and IgE. The induction of
    eosinophils and lgG1 were inhibited by NAC.
    Generally, UFP+OVA mice had greater signs of
    inflammation than the other groups as
    determined by pulmonary histopathology and
    airway morphometry. UFP had a greater PAH
    content than fine particles. UFP significantly
    increased IL-5, IL-13, TNF-a, IL-6, KC,  MCP-1,
    and MIP-1a.
    Reference: Li et
    al. (2009, 1904571
    
    Species: Mouse
    
    Cell Line: RAW
    264.7
    CAPs (downtown Los Angeles, CA from
    major freeway, traffic mainly passenger
    cars and diesel trucks; Jan. 2007 or
    Sept. 2006)
    
    Ultrafine carbon black (UFCB)
    
    Particle Size: Fine- <2.5 pm (diameter),
    UF-0.15pm (diameter)
    Route: Cell Culture
    
    Dose/Concentration: 1, 5, 8.3, 10 pg/mL
    
    Time to Analysis: NR
    UFP induced greater HO-1 expression than fine
    particles. The higher PAH content of UFP
    correlated with HO-1 expression.
    December 2009
                                                      D-138
    

    -------
         Study
                 Pollutant
                                                                            Exposure
                                                                                                                          Effects
    Reference: Liu et
    al. (2008, 1567091
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 11wk
    
    Weight: NR
                      DEP (5500-watt single-cylinder diesel
                      engine generator (Yanmar, Model YDG
                      5500E), 406 cc displacement air-cooled
                      engine, Number 2 Diesel Certification
                      Fuel, 40 weight motor oil)
                      Particle Size:
                                       ^m 
                                         Route: Intranasal Exposure
    
                                         Dose/Concentration: Average particle
                                         concentration: 1.28 mg/m3
    
                                         Time to Analysis: Four groups: saline+air control,
                                         saline+DEP, A. fumigatus+air, A.fumigatus+DEP. A.
                                         fumigatus exposure every 4 days for 6 doses. DEP
                                         exposure 5 h/dayfor 3 wk concurrent with A.
                                         fumigatus exposure.
                                                                                                        A.fumigatus+DEP increased IgE, the mean BAL
                                                                                                        eosinophil percentage, goblet cell hyperplasia,
                                                                                                        and eosinophilic and mononuclear cell
                                                                                                        inflammatory infiltrate around the airways and
                                                                                                        blood vessels compared to the A. fumigatus or
                                                                                                        DEP treatments. A.fumigatus+DEP also caused
                                                                                                        methylation at the IFN-y promoter sites CpG-53,
                                                                                                        CpG-45, and CpG-205.
    Reference: Liu et
    al. (2007, 0930931
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 11wk
                      DEP: 5500-watt single-cylinder diesel
                      engine.
    
                      Particle Size: NR
                                                           Route: Inhalation
    
                                                           Dose/Concentration: Average particle
                                                           concentration 1.28 mg/m3.
    
                                                           Time to Analysis: 1. Aerosol vehicle (saline) + air
                                                           2. Aerosol vehicle (saline) + DEP
                                                           3. A. fumigatus + air
                                                           4. A. fumigatus + DEP
    
                                                           A. fumigatus: 62.5 pg aerosolized protein extract in
                                                           50 pL PBS; 6 total doses, every 4 d.
    
                                                           DEP exposure 5 h/day 3wk concurrent with A.
                                                           fumigatus.
                                                                                       IgE Production: IgE production increased with
                                                                                       the A.fumigatus treatment and increased further
                                                                                       with the A.fumigatus and DEP treatment.
    
                                                                                       Histopathology: A. fumigatus with DEP caused
                                                                                       an increase in goblet cell hyperplasia and
                                                                                       eosinophil and mononuclear cell infiltrate around
                                                                                       the airways and blood vessels as compared to
                                                                                       the control and DEP treatments.
    
                                                                                       Gene Methylation: Greater methylation at the
                                                                                       CpG-53 site of the IFN-y promoter occurred
                                                                                       under the A. fumigatus + DEP treatment
                                                                                       compared to the A. fumigatus or DEP
                                                                                       treatments. The DEP treatment did not induce
                                                                                       methylation. Methylation correlated with
                                                                                       increased IgE and hypomethylation with
                                                                                       decreased IgE. Hypomethylation occurred in the
                                                                                       IL-4 promoter under the A. fumigatus + DEP
                                                                                       treatment.
    Reference:
    Lundborg et al.
    (2007, 0960401
    
    Species: Rat
    
    Gender: Male
    
    Strains: SD
    
    Age: NR
    
    Weight: 300-400 g
    
    Cell Line: AM
    Carbon-Black Particles (93% C)
    
    DEPs (97% C) - toluene-extracted
    
    10-fold Cr, Mn, N; 50-100 fold Al, Cd,
    Cu, Fe, Mg, Pb, Zn more in DEP
    aggregates
    
    Particle Size: Carbon aggregates: 0.17
    + 0.08 pm (mean diameter)
    
    Diesel Particles: 0.69 + 0.46 pm (mean
    diameter)
    
    Primary particles:  0.044 + 0.01 pm
    (mean diameter)
                                                           Route: Cell Culture (0.5x106 AM/well)
    
                                                           Dose/Concentration: 20 |jg/mL
    
                                                           surface area: 159 + 4m2/g
    
                                                           Time to Analysis: 6 different experiments. AM pre-
                                                           exposed to carbon or washed DEP. Loaded with
                                                           particles. Incubated with S. pneumoniae, ATCC
                                                           strain or clinical isolates.
                                                                                                         Effect of Time on Survival of S. Pneumoniae
                                                                                                         when Incubated with Carbon Loaded AM:
                                                                                                         Loading AM with carbon significantly increased
                                                                                                         the bacterial survival. Bacteria opsonization
                                                                                                         decreased bacterial survival.
    
                                                                                                         Effect of Carbon Load in AM on Survival of
                                                                                                         S. Pneumoniae: Bacterial survival increased in
                                                                                                         a dose-dependent manner as the carbon
                                                                                                         particle load of AM increased.
    
                                                                                                         Survival of S. Pneumoniae after Incubation
                                                                                                         with Carbon or Washed Diesel Loaded AM:
                                                                                                         Bacterial survival increased in carbon loaded
                                                                                                         AM compared to the control. No difference
                                                                                                         existed with the washed diesel particles.
    
                                                                                                         Survival of the ATCC Strain and Clinical
                                                                                                         Isolates of S. Pneumoniae when Incubated
                                                                                                         with Carbon Loaded AM or Control AM:
                                                                                                         Carbon significantly increased the CFU of
                                                                                                         opsonized and unopsonized bacteria for the
                                                                                                         ATCC strain and clinical isolates.
    
                                                                                                         Ability of carbon or washed diesel loaded
                                                                                                         AM, incubated with the ATCC strain of S.
                                                                                                         pneumoniae, to induce LPO of lung
                                                                                                         surfactant: A 97% increase in the surfactant
                                                                                                         LPO occurred after incubation with washed
                                                                                                         diesel loaded AM compared to control AM. The
                                                                                                         effect of washed diesel particles was
                                                                                                         significantly greater than that of carbon
                                                                                                         particles.
    
                                                                                                         LPO by carbon loaded AM incubated with the
                                                                                                         ATCC strain or clinical isolates in the
                                                                                                         presence of absence of surfactant: LPO
                                                                                                         induced by AM increased when incubated with
                                                                                                         carbon loaded AM compared to control AM.
    December 2009
                                                      D-139
    

    -------
         Study
                 Pollutant
                     Exposure
                                                                                                                          Effects
    Reference:
    Matsumoto et al.
    (2006, 0980171
    
    Species: Mouse
    
    Gender: Female
    
    Strains: BALB/c
    
    Age: 6 wk
    
    Weight: 15-20 g
    DE (collected from a 2369 cm  diesel
    engine operated at 1050 rpm and 80%
    load with commercial light oil; engine
    exhaust passed through a particulate air
    filter and charcoal filer)  Diluted DE
    introduced into the exposure chamber.
    
    Composition of the DE: 3.5 + 0.1 ppm
    CO, 2.2 + 0.3 ppm N02, <0.01  ppm S02
    and 103.1 ± 9.2 pg/m3 DEP
    
    Particle Size: NR
    Route: Whole-body Inhalation
    
    Dose/Concentration: 100 pg/m3 DE
    
    Time to Analysis: Mice were initially sensitized w/
    OVA (20ug absorbed to 2 mg alum diluted with 0.5
    ml saline) via ip injection on day 0, 6 and 7. Two
    wks later the mice were challenged with OVA
    (0.1 mg in 0.1 ml saline) intranasallyonday21.
    
    DEfor1dor1,2, 3, 4 or 8 wk (at 7 h/day for 5
    days/wk).
                                                                                                         Airway Hyperresponsiveness: Exposure to
                                                                                                         DE significantly increased airway reactivity to
                                                                                                         methacholine after 1 wk in both 24 and 48
                                                                                                         mg/mL Mch and after 4 wk in the 48 mg/mL DE
                                                                                                         exposure caused an increase in airway
                                                                                                         sensitivity after 1 wk of exposure, 4 wk and 8 wk
                                                                                                         of exposure did not result in a significant
                                                                                                         increase.
    
                                                                                                         BAL Cells: The total cell count was increased
                                                                                                         after 1 wk of DE exposure. This increase was
                                                                                                         mostly due to an increase in eosinophils. After 1
                                                                                                         wkthe total cell count dropped drastically even
                                                                                                         after continuous exposure to DE. DE did not
                                                                                                         effect the number of CDS, CD4, CDS or NK1
                                                                                                         cells at any point in time.
    
                                                                                                         Cytokine/Chemokine mRNA Levels: DE
                                                                                                         exposure on day 1 caused an increase in mRNA
                                                                                                         levels of IL-4, IL-5 and IL-13 when compared to
                                                                                                         the control mice but longer periods of DE
                                                                                                         exposure failed to cause an increase. Protein
                                                                                                         levels of IL-4 were significantly elevated at
                                                                                                         compared to control at day 1, but did not persist
                                                                                                         with time.  mRNA levels of MDC were increased
                                                                                                         at 1 wk of exposure (compared to control) but
                                                                                                         also decreased at time periods after. mRNA
                                                                                                         levels of RANTES were increased at 2 and 3 wk
                                                                                                         after exposure and remained elevated at 4 wk
                                                                                                         but not significantly. The level of RANTES
                                                                                                         protein increased as the weeks went along, but
                                                                                                         increased significantly only at 8 wk.
    
                                                                                                         Histopathology: OVA sensitization caused an
                                                                                                         increase peribronchial and perivascular
                                                                                                         infiltration of inflammatory cells which peaked at
                                                                                                         1 wk after exposure and decreased afterward.
                                                                                                         DE exposure did not cause/show any additional
                                                                                                         signs of inflammation.
    Reference:
    Morishita et al.
    (2004, 0879791
    
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    
    Age: 10-12 wk
                      CAPs (generated from ambient air in an
                      urban Detroit community).
    
                      Particle Size: 0.1-2.5pm
                                         Route: Whole-body Inhalation
    
                                         Dose/Concentration: July 676 pg/m3' September
                                         313|jg/m3
    
                                         Time to Analysis: First rats were sensitized (days
                                         1-3) and challenged (days 14-16) with saline
                                         (control) or OVA by intranasal instillation (5% in
                                         saline, 150 pL/nasal passage).
    
                                         4 days after the last intranasal challenge, rats
                                         began exposure in the chambers. Exposures were
                                         10 h long. The July exposure was for 4 consecutive
                                         days. The September exposure was for 5
                                         consecutive days.
                                                  Recovery of Trace Elements in Animal Lung
                                                  Tissues: July Exposure-Anthropogenic trace
                                                  elements were below limit of detection in
                                                  pulmonary tissue of animals exposed to July
                                                  CAPs. September Exposure- Several elements
                                                  were recovered from pulmonary tissue during
                                                  the Sept. exposure. La concentrations were
                                                  increased in both control/CAPs exposure and in
                                                  the OVA/CAPs exposure groups. V
                                                  concentration was increased in OVA/CAPs
                                                  exposed animals but not in rats exposed to just
                                                  CAPs. S content was only significant in animals
                                                  exposed to OVA/CAPs compared to the non-
                                                  exposed control.
    
                                                  Particle Characterization: July PM had an
                                                  average mass concentration twice as high as
                                                  the September mass concentration. S
                                                  concentration was four-folds higher in July PM.
                                                  In the September PM- the concentration of La
                                                  was 12.5 fold higher than in July PM, V was 2.7
                                                  fold higher than in July PM and Mnwas 1.5 fold
                                                  higher than in July PM.
    
                                                  BALF Analysis: Eosinophil concentration was
                                                  not significantly different when comparing rats
                                                  exposed to CAPs only in either July or
                                                  September (this was explained by the elapsed
                                                  time between exposure and BALF collection).
                                                  However OVA and CAP exposure  in the
                                                  September group led to elevated eosinophil
                                                  levels. Similarly, the protein content was only
                                                  significantly increased in the September
                                                  OVA/CAP exposed rats, compared to the control
                                                  group.
    December 2009
                                                      D-140
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Nygaard et al.
    (2005, 0886551
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 6-7 wk
    Coarse and fine ambient air particles
    collected in Rome (spring), Oslo (1-
    summer, fine only, 2- following spring,
    fine and coarse), Lodz (summer) and
    Amsterdam (spring). These represent
    areas with high population and
    dominance of traffic.
    
    DEP (Standard reference material
    1650a)
    
    Particle Size: Fine PM 0.1-2.5 pm;
    Coarse PM 2.5-10 pm
    Route: Subcutaneous Injection into mouse
    footpads.
    
    Dose/Concentration: 100 |jg of particle
    
    Time to Analysis: Animals were in eight groups: 1.
    Control- Hank's Balanced Salt  Solution
    2. OVA- 50 ug 3. OVA (50 pg)+ Amsterdam Coarse
    PM (100 pg) 4. OVA (50 pg)+ Amsterdam Fine PM
    (100 pg) 5. OVA (50 pg)+  Lodz Coarse PM (100
    pg) 6.  OVA (50 pg)+ Lodz Fine PM (100 pg) 7. 5.
    OVA (50 pgj+ Oslo Coarse PM (100 pg) 8. OVA (50
    pg)+ Oslo Fine PM (100 pg)
    
    Analysis 5 days after injection.
    Cell Numbers and Cell Phenotypes in the
    Lymph Node: The overall number of B
    lymphocytes, lymph node cells, PLN cells, and
    the expression of MHC class II, CD86 and CD23
    on B lymphocytes were increased by
    coexposure of OVA+ the particles compared to
    the OVA or particle groups alone. The OVA +
    particle groups displayed a significant decrease
    in T lymphocytes. Particles only significantly
    increased the number of lymph node cells and
    MHC Class II expression. There were no
    differences observed between coarse and fine
    PM fractions.
    
    Cytokine Production  by Lymph Node (ex
    vivo culture of popliteal lymph node cells):
    The OVA + particle (DEP and Oslol only)
    significantly increased  IL-4 and IL-10 levels. No
    change was observed in  IFN-y. The particle
    groups only increased  IL-4 and IL-10. All coarse
    and fine particle fractions co-exposed with OVA
    significantly increased  IL-4 and IL-10 compared
    to OVA alone. There was no significant
    difference between coarse and fine particles.
    IFN-y levels were not significantly affected by
    most of the groups, but the fine fractions of PM
    consistently produced higher levels of IFN-y.
    
    Lymph Node Histology: OVA+  particle groups
    resulted in significantly enlarged lymph nodes
    and the formation of germinal centers.
    Reference:
    Nygaard et al.
    (2005,,
    Polysterene Particles (PSP)
    
    Particle Size: 0.1 pm (diameter)
    Species: Mouse
    
    Gender: Female
    
    Strains: BALB/c
    
    Age: 6-8 wk
    Route: Subcutaneous Injection into footpads.
    
    Dose/Concentration: 40 pg PSP (5.94x1010
    particles) per injection suspended in HBSS. One
    injection per footpad
    
    Time to Analysis:! HBSS
    2. OVA (10 pg per injection)
    3. PSP (40 pg per injection)
    4. OVA (10 pg per injection) + PSP (40 pg per
    injection).
    
    Antibody experiments: reinjected with 10 pg OVA
    on day 21. Killed on day 26.
    
    Popliteal lymph node cell experiments-- animals
    injected. Killed 1 to 21 days post-injection.
    OVA-specific IgE, lgG1 and lgG2a
    Antibodies: Analysis at day 26 indicated IgE,
    lgG1 levels were significantly higher in mice
    exposed to OVA+PSP compared to mice
    injected with HBSS, OVA or PSP. No significant
    difference was observed for lgG2a levels.
    
    Number of Particle Containing Cells: There
    was no significant difference between PSP
    alone and OVA+PSP. Throughout days 0 -21 the
    number of particle-containing cells in the PSP or
    OVA+ PSP groups were significantly greater
    than the HBSS group.
    
    Total Cell Numbers, B and T Lymphocytes
    and MHC class II Expression: The total cell
    number and B lymphocytes significantly
    increased by coexposure to OVA+ PSP when
    compared to the other groups. Both OVA and
    OVA+PSP increased T lymphocytes on Days 1,
    3 and 5. MCH class II expression was
    significantly higher in the OVA+PSP group on
    days 5, 7 and 21 than other groups.
    
    Cell Types and Surface Markers: The number
    of CD40+ B Lymphocytes showed a slight but
    significant decrease with OVA+PSP and OVA
    compared to HBSS and PSP. CD86+, CD23+
    and CD69+ B lymphocytes were significantly
    higher in OVA+PSP group than other groups.
    PSP alone did not affect CD86+ or CD23+
    levels.
    
    Cytokine Production: IL-4 and IL-10 were
    significantly higher in the OVA+PSP group when
    compared to the other groups. OVA alone
    caused a slight increase compared to PSP. PSP
    did not alter IL-4 or IL-10 levels.
    December 2009
                                                      D-141
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Nygaard et al.
    (2004, 0585581
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 6-7 wk
    
    Weight: NR
    CB (carbon black/DEP)
    
    Polystrene Particles (PSP)
    
    Particle Size: PSP diameter: 0.0588,
    0.202, 1.053, 4.64 or 11.14pm
    Route: Single subcutaneous injection into footpad
    
    Dose/Concentration: 10 pg OVA + 40 pg (low
    dose) or 200 pg (high dose) of particles
    
    Time to Analysis: 5 days after OVA injection
    OVA Specific IgE and Ig2a: OVA with CB, DEP
    or PSP of diameters 0.0588 and 0.202 pm
    increased IgE compared to OVA alone, as well
    as the 1.053, 4.64 and 11.14 pm PSP. OVA with
    0.0588 pm PSP or CB significantly increased
    lgG2a compared to OVA alone.
    
    Primary Cellular Response: All OVA and PSP
    groups (except the low dose of 11.14 pm PSP)
    had more total lymph node cell numbers than
    the OVA alone group. The low and high does
    groups of 0.202 pm PSP had the greatest
    amount of cell proliferation and lymphoblasts.
    The OVA and 0.202 PSP treatment produced
    the greatest amounts of B lymphocytes, IL-4, IL-
    10 and IFN-Y.  IL-2 in the PLN cells was
    significantly lower in both dosage groups of OVA
    and 0.202 PSP than the OVA control.
    
    Particle Mass, Size, Number and Surface
    Area: Total particle surface area explained 64%
    of the variance in the IgE levels. 60-80%
    variance of the PLN cellular parameters (except
    CD23) were explained by total particle surface
    area, number and diameter.
    Reference: Reed
    et al. (2008,
    Species: Mouse
    
    Gender: Male,
    Female (only
    BALB/c)
    
    Strain: C57BL/6,
    A/J, BALB/c
    
    Age: NR
    
    Weight: NR
    GEE (two 1996 General Motors 4.3-L V-
    6 engines; regular, unleaded, non-
    oxygenated, non-reformulated gasoline
    blended to US average consumption for
    summer 2001 and winter 2001-2002-
    Chevron-Phillips)
    
    Particle Size: 150 nm(MMAD)
    Route: Whole-body Inhalation
    
    Dose/Concentration: PM: Low- 6.6 ± 3.7 pg/m3,
    Medium- 30.3 ± 11.8 pg/m3, High- 59.1 ± 28.3
    pg/m3
    
    Time to Analysis: A/J- 6 h/day, 7days/wk, 3 days-6
    mo. C57BL/6- 1wk exposure.  Instillation of P.
    aeruginosa. Killed 18 h postinstillation. BALB/c-
    Pregnant females exposed GD1 and throughout
    gestation. Offspring  exposures continued until 4wk-
    old. Half of offspring sensitized to OVA. Tested for
    airway reactivity by methacholine challenge 48 h
    post-instillation and euthanized.
    The kidney weight of female A/J mice decreased
    at 6 mo. and was strongly related to PM by the
    removal of emission PM. PM-containing
    macrophages increased by 6 mo.
    Hypomethylation occurred in females at 1 wk.
    The clearance of P. aeruginosa was unaffected
    by exposure. Serum total IgE significantly and
    dose-dependently increased. OVA-specific IgE
    and lgG1 gave slight exposure-related evidence
    but were not significant.
    Reference:
    Roberts et al.
    (2007, 0976231
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    
    Age: 10 wk
    
    Weight: 250-300 g
    R-Total = ROFA (Residual oily fish ash)    Route: IT Instillation
    R-Soluble = Soluble fraction of ROFA
    R-Chelex = R-Soluble+Chelex (insoluble
    resin)
    Particle Size: 2.2 pm (mean diameter)
    Dose/Concentration: 10 mg/kg (2.5-3 mg)
    
    Time to Analysis: Pre-exposure to ROFA samples
    on Day 0. Inoculation with 5*10 L. Monocytogenes
    or saline on day 3. Sacrifice on days 6, 8,10.
    Uninfected Groups: Compared to the controls,
    the R-total and R-soluble groups had increased
    LDH, PMNs, lymphocytes and AMs. The R-total
    group had a slight, but significant increase in IL-
    6 and the R-soluble group had a decrease in IL-
    2.
    
    Infected Groups: The R-soluble group had
    increased levels of LDH (which also increased
    for the R-total  group), albumin, BALF cells, NK
    cells, PMA-stimulated and zyomason-stimulated
    CL compared to all other groups at various time
    points. NOX was significantly elevated in the R-
    soluble group  at early time points, but in later
    time points R-soluble and R-total AMs produced
    less NOX than the controls. IL-10 and IL-6
    increased in the R-soluble group, while IL-12,
    IL-4 and IL-2 decreased. IL-12 also decreased
    in the R-total group.
    Reference:
    Saxena et al.
    (2003, 0543951
    
    Species: Mouse
    
    Gender: Female
    
    Strain: C57B1/6J
    
    Age: 18-30 wk
    
    Weight: NR
    DEPs (standard)
    
    Particle Size: NR
    Route: Intrapulmonary Instillation
    
    Dose/Concentration: 100 pg/mouse
    
    Time to Analysis: Pre-exposure to 2.5x104
    bacillus Calmette-Guerin bacteria (BC G) with or
    without coadministration of DEP.  Sacrifice 5 wk
    later.
    The BC G + DEP group had four times the BC G
    lung load than BC G alone. The load was
    significantly greater in other organs in the BC G
    + DEP group. Interstitial lymphocytes, T, B and
    NK cells were increased in the BC G + DEP
    group over the DEP-alone group. DEP caused
    no release of NO by AMs, but inhibited the
    release of NO in response to IFN-y. Except for
    CDS cells,  no increase in  IFN-y was seen in the
    BC G  + DEP group.
    December 2009
                                                      D-142
    

    -------
         Study
                 Pollutant
                     Exposure
                                                                                                      Effects
    Reference:
    Schneider etal.
    (2005, 0883681
    
    Species: Mouse
    
    Strain: BALB/c
    
    Cell Line: RAW
    264.7
    SRM 1648 (greater than 63% inOC; 4-    Route: Cell Culture (625,000 cells/cm' in 96 well
    7% OC; Si, S, Fe, Al, K greater than 1 %   plate)
    by weight; Mg, Pb, Na, Zn, Cl, Ti, Cu, As                     „-,„.,,-„„.,„    Jm?
    Cr, Ba, Br, Mn less than  1%)            Dose/Concentration: 0, 7.8,15.6, 31.2, and 62.5
    Ti62
    
    Particle Size: Ti02 = 0.3 pm average,
    1.0pm max
    SRM 1648 = 0.4 pm (mean diameter)
                                        Time to Analysis: 1, 3, 6, and 12 h
                                                 No significant toxicity was exhibited by SRM
                                                 1648. The rate of dye oxidation was significantly
                                                 higher in SRM 1648-exposed cells. SRM 1648
                                                 significantly increased reduced glutathione
                                                 compared to the control at the 12-h time point.
                                                 SRM 1648 increased GSH and concurrently
                                                 caused significant PGE2 production compared
                                                 to the no ester control at the 6-h and 12-h time
                                                 points.
    Reference:
    Schober et al.
    (2006, 0973211
    
    Species: Human
    
    Gender: Male and
    Female
    
    Age: 21-39 yr
    treatment group;
    23-32 yr control
    group
    
    Tissue Type:
    Whole blood
    samples
    PM - organic extracts of airborne sample  Route: Cell Culture
    AERexld - urban aerosol 1 day sample
    (total air volume-1270m3)
    
    AERexSd - urban aerosol 5 day sample
    (total air volume-6230m3)
    
    rBetv 1 (birch pollen allergen 1a,
    Biomay, Vienna, Austria)
    
    Particle Size: NR
    Dose/Concentration: 100 pi heparinized whole
    blood
    
    Time to Analysis: Blood stimulated with PBS/IL-3
    foMOmin. Incubated with rBet v 1 alone or with
    AERex for 20 min. Ice bath 5 min.  Incubated with
    antibody reagent 20 min.
                                                                                     Nine organic compound classes were identified
                                                                                     in AERexld and AERexSd, with AERexld
                                                                                     having 20 times more PAHs. Basophil activation
                                                                                     increased in all treatment groups up to 90%,
                                                                                     with AERexld being the most pronounced. 5-50
                                                                                     fold lower concentrations of AERexld were
                                                                                     needed to achieve the maximal effect on
                                                                                     basophil activation. AERex-induced
                                                                                     enhancement of CD63 upregulation of rBet v 1
                                                                                     in sensitized basophils occurred in a dose-
                                                                                     dependent manner. The AERex-alone treatment
                                                                                     did not affect CD63 expression.
    Reference: Shwe
    et al. (2005,
    1115531
    
    Species: Mouse
    
    Gender: Male
    
    Strains: BALB/c
    
    Age: 8 wk
    
    Weight: NR
    CB = carbon black particles (Degussa,
    Germany)
    
    CB14:
    
    C: 96.79%
    
    1-1:0.19%
    
    N:0.13%
    
    3:0.11%
    
    Ash: 0.05%
    
    Others including 0: 2.74%
    
    CB95:
    
    C: 97.98%
    
    H:0.15%
    
    N: 0.28%
    
    S: 0.46%
    
    Others including 0:1.14%
    
    Particle Size: CB14 = 14 nm (primary
    particle size); CB95 = 95 nm (primary
    particle size)
    Route: IT instillation
    
    Dose/Concentration: 25,125, or 625 pg in 1 ml
    saline solution
    
    Time to Analysis: 1/wk for 4 wk; 4or24h  after
    last instillation
                                                                                     BALF Cells: In CB14, the total number of BAL
                                                                                     cells increased significantly and dose-
                                                                                     dependently. In CB95, only the 625pg dose
                                                                                     showed a significant increase.
    
                                                                                     Cytokine and Chemokine: For CB14 and
                                                                                     CB95,125 or 625 pg showed a significant IL-1B
                                                                                     increase in a dose-dependent manner. For
                                                                                     CB14, only the 625 pg dose showed a
                                                                                     significant IL-6 increase. No difference was
                                                                                     observed in the CB95 group. For CB14, only
                                                                                     larger doses showed a significant TNF-a
                                                                                     increase. For CB95, no significant differences
                                                                                     were observed.
    
                                                                                     In BAL Fluid: CCL-2 production was
                                                                                     significantly increased for the 625pg dose in
                                                                                     both the CB14 and  CB95 groups.  CCL-3
                                                                                     production was significantly increased for the
                                                                                     larger doses in both the CB14 and CB95
                                                                                     groups.
    
                                                                                     Splenic Lymphocytes: No significant
                                                                                     differences were detected among  the CB14
                                                                                     dosages, except for CD8+. No significant
                                                                                     differences were observed among the various
                                                                                     groups for CB95.
    
                                                                                     Deposition in Lymph Nodes: For all dosages,
                                                                                     greater deposition of CB14 than CB95 was
                                                                                     observed.
    
                                                                                     Chemokine mRNA Expression in Lungs and
                                                                                     Lymph Nodes: At 125 pg, significant increases
                                                                                     of CLL-3 mRNA expression was observed for
                                                                                     CB14; for CB95,  no differences were detected.
    December  2009
                                                     D-143
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference: Sigaud
    et al. (2007,
    0961001
    
    Species: Mouse
    
    Gender: Male
    
    Strains: BALB/c
    
    Age:8-10wk
    
    Weight: NR
    CAPs: Concentrated Ambient Particles
    (Collected from ambient Boston air on
    Teflon filters.)
    
    Ti02
    
    IFN-Y
    
    S. pneumoniae (ATCC 6303, American
    Type Culture Collection, Manassas, VA)
    
    Particle Size:  CAPs: <2.5 pm
    Route: IFN-Y priming: aerosol
    
    Particle exposure and infection: Intranasal
    Instillation
    
    Dose/Concentration: CAPS or Ti02: 50 pg/50 pL
    PBS
    
    S. pneumoniae: 105CFU/25 \A saline
    
    Time to Analysis: Primed for 15 min
    
    One time particle exposure 3 h post priming with
    lung RNA analyzed 3, 6, 24 h after exposure
    
    Sacrificed 24 h after exposure or one time infection
    Inflammation: Saline-primed and unprimed
    mice exposed to CAPs produced a significant
    increase in PMNs in the lung (100% more than
    mice exposed to Ti02.) Groups primed with IFN-
    ythen exposed to CAPs produced a strong
    inflammatory response, a 2.5 increase in PMNs
    when compared to the increase caused by
    PBS+ CAPs exposure.
    
    Cytokine Levels: IFN-y primed and CAPs
    exposed groups
    
    Inflammation* S. Pneumo Infection: Saline-
    primed and unprimed mice exposed to CAPs
    produced a significant increase in PMNs in the
    lung  (100% more than mice exposed to Ti02.)
    Groups primed with IFN-y then exposed to
    CAPs produced a strong inflammatory
    response, a 2.5 increase in PMNs when
    compared to the increase caused by
    PBS+CAPs exposure.
    
    Cytokine Levels: IFN-y primed and CAPs
    exposed groups showed a 1.5-fold increase
    over  the control.
    
    PMNs: Treatment with CAPs enhanced
    inflammation, causing a 2-fold increase in PMN
    numbers as compared to the infected control.
    IFN-y+CAPs+S. pneumo produced a 3.5 fold
    increase compared to the infected control and a
    1.6-fold increase compared to
    PBS+CAPs+S.pneumo. Despite increased
    numbers of PMNs in the IFN-y+CAPs groups,
    the lungs were unable to clear the S. pneumo
    infection.
    
    Bacterial Load: Control groups showed
    efficient clearance of bacteria after infection.
    Unprimed, CAPs-treated, infected groups did
    not show a decrease  in bacterial numbers. IFN-
    y+CAPs showed a 2.5-fold increase in bacterial
    numbers.
    
    Histopathology: Indicated moderate
    pneumonia in PBS+CAPs and severe
    pneumonia in IFN-y+CAPs. The other groups
    did not indicate areas of pneumonia.
    
     Bacterial Uptake AM and PMN Cells: In all
    the treated groups, the bacterial content in AMs
    showed a decrease, with a more marked
    decrease in the IFN-y+CAPs group, but these
    decreases were not statistically significant.
    Groups exposed to CAPs showed a statistically
    significant decrease in bacterial uptake by
    PMNs.
    
    ROS Levels in AM and PMN Cells:
    Intracellular ROS significantly increased in AM
    cells  in the IFN-y+CAPs group, approximately
    50%  greater than controls. In PMNs, iROS
    increased 100% in the IFN-y+CAPs groups as
    compared to the controls.
    December  2009
                                                     D-144
    

    -------
         Study
                 Pollutant
                     Exposure
                                                                                                                         Effects
    Reference:
    Steerenberg et al.
    (2004, 0874741
    
    Species: Rat
    
    Gender: Male
    
    Strain: Wistar
    Kyoto
    
    Age: 6-8 wk
                      DEP:SRM1650a (NIST, Gaithersburg,
                      MD
    
                      EHC-93: ambient PM (Ottawa, Canada)
    
                      03 (positive control)
    
                      L. mono: Listeria monocytogenes (strain
                      L242/73type4B)
    
                      Particle Size: DEP, EHC-93: NR
                                         Route: DEP/EHC-93: intranasal droplet; 03:
                                         Whole-body inhalation
    
                                         Dose/Concentration: DEP/EHC-93: 50 pg (1.0
                                         mg/ml)
    
                                         03: 2mg/m3
    
                                         L. mono: 0.2 or 0.3 ml (5x106 PFU/ml) 1 have
                                         emailed author regarding correct dose
    
                                         Time to Analysis: DEP/EHC-93:1/day for 7 days
                                         (-7 days  to -1 days)
    
                                         03 24 h/day for 7 days (-7 days  to -1 daysR
    
                                         All rats infected on day 0. Sacrificed on days 3, 4,
                                         or 5.
                                                  Body weight: Growth declined for 03 exposed
                                                  group while DEP or EHC-93 groups grew
                                                  progressively. Exposure to L. mono caused all
                                                  groups to decline in weight.
    
                                                  Bacterial Count in the Lung: The number of
                                                  bacteria in the lung of those rats exposed to 03
                                                  was significantly greater than those exposed to
                                                  saline. No differences in bacteria number were
                                                  found for rats exposed to saline, EHC-93 or
                                                  DEP at any time.
    
                                                  Bacterial Count in the Spleen: The 03
                                                  exposed group exhibited statistically significant
                                                  increases in bacteria numbers when compared
                                                  to the saline-treated group.  No differences in
                                                  bacteria number were found for rats exposed to
                                                  saline, EHC-93 or DEP at any time. Exposure to
                                                  03 decreases the defense of the respiratory
                                                  tract against L. mono infection; however, DEP
                                                  and  EHC-93 did not appear to affect the host
                                                  defense system in regards to clearing/fighting L.
                                                  mono.
    Reference:
    Steerenberg et al.
    (2005, 0886491
    
    Species: Mouse
    
    Gender: Male
    
    Strain:
    BALB/cByJ.ico
    
    Age: 6-8 wk
    PM: collected from Rome, Oslo, Lodz,
    Amsterdam and De Zilk during the
    spring, summer and winter.
    
    Rome, Oslo, Lodz and Amsterdam
    represent areas with high population and
    dominance of traffic. DeZilk, selected as
    a negative control site, has low traffic
    emissions and natural allergens.
    
    EHC-93: used as a positive control
    
    OVA: Ovalbumin
    
    Particle Size: Coarse PM: 2.5 -10.0 pm
                      (MMAD
                      (MMAD
           ; Fine PM: 0.1 - 2.5pm
                      EHC-93: NR
           ; Ultrafine: <0.1 pm(MMAD);
    Route: Intranasal Exposure
    
    OVA challenge: aerosol
    
    Dose/Concentration: PM: 450 pg PM (at 0, 3, or 9
    mg/ml)
    
    OVA sensitization: 50 pg (0.4 mg/ml).
    
    OVA challenge: 20 pg (0.4 mg/ml)
    
    EHC-93 was administered at
    0 - 900 pg to evaluate any dose-response
    relationship.
    
    Time to Analysis: Sensitization and PM exposure
    on days 0,14
    
    Challenged on days 35, 38, 41 for 20 min/day
    
    Sacrificed on day 42
                                                                                                        Effects of Coarse and Fine Particles:
                                                                                                        Immunoglobulins: 6/13 of the coarse and 9/13
                                                                                                        fine PM samples induced an increase in IgE and
                                                                                                        IgGlwhen compared to the control. lgG2a levels
                                                                                                        were increased in 3/13 of the coarse and 5/13 of
                                                                                                        the fine PM. Particles from De Zilk induced all
                                                                                                        three immunoglobulins, except the fine PM did
                                                                                                        not induce lgG2a. De Zilk was intended as a
                                                                                                        negative control (see Table 3). Analysis among
                                                                                                        the sites comparing the subclasses of
                                                                                                        antibodies indicated a rank as follows:  Lodz
                                                                                                        >Rome 2 Oslo.
    
                                                                                                        Histopathology: 9/13 of the coarse PM
                                                                                                        samples and 5/13 of the fine PM samples
                                                                                                        induced an inflammatory response.
    
                                                                                                        BALF Cells: Lodz (spring/ summer) coarse and
                                                                                                        fine PM induced a significant increase in
                                                                                                        eosinophils, neutrophils and monocytes. The
                                                                                                        coarse and fine PM from Rome (spring) induced
                                                                                                        an increase in neutrophils and the coarse PM in-
                                                                                                        duced an increase in eosinophils. Also both
                                                                                                        Lodz and Rome from the coarse PM from the
                                                                                                        spring induced an increase in macrophages.
                                                                                                        Other PM samples did not have an effect on
                                                                                                        BAL cell counts.
    
                                                                                                        Cytokine Production: None of the samples
                                                                                                        produced a significant effect on IL-4 levels. IFN-
                                                                                                        Y levels were significantly decreased in mice
                                                                                                        exposed to the fine PM fraction (in 8/13 of the
                                                                                                        samples) when compared to control. Coarse
                                                                                                        particle exposure did not appear to affect IFN-y
                                                                                                        levels.  TNF-a levels were significantly increased
                                                                                                        (in 2 of the 13 samples) when exposed to
                                                                                                        coarse PM; fine PM showed similar responses
                                                                                                        compared to the OVA only group. IL-5 was
                                                                                                        significantly increased in 4/13 of the coarse and
                                                                                                        fine PM samples.
    
                                                                                                        Analysis of PM Components: Samples from
                                                                                                        Lodz, Oslo and Rome (all spring) were
                                                                                                        evaluated and the water-soluble coarse PM
                                                                                                        fraction showed increased immunoglobulin and
                                                                                                        pathological responses and  the water-insoluble
                                                                                                        fine PM fraction from Lodz (Spring) showed
                                                                                                        increased reactivity Leukocytes and cytokines
                                                                                                        showed no major differences.
    December 2009
                                                      D-145
    

    -------
         Study
    Pollutant
    Exposure
    Effects
    Reference:        EHC-93
    Steerenberg et al.
    (2004,0879811     OVA
    
    Species: Mouse    Particle Size: NR
    
    Gender: Male
    
    Strain:
    BALB/cByJ.ico
    
    Age: 6-8 wk
    
    Treatment:
    1.C.D2-VH6:
    NrampIS and
    NrampIR deficient
    
    2. B6.129P2:
    Nos2tmLau: iNOS
    deficient
    
    3. BALB/CIL4
    (tm2Nnt): deficient
    in IL-4
    
    4. BALB/c (wild
    type) pretreated
    with N-
    Acetylcysteine
    (MAC)
                            Route: Sensitization, Challenge: Intranasal
    
                            MAC: IP injection
    
                            Dose/Concentration: OVA: 200 pg (0.4 mg/ml)
    
                            EHC-93:150 pg (3 mg/ml)
    
                            MAC: 320 mg/kg
    
                            Time to Analysis: OVA-only or OVA+EHC-93
                            sensitization on days 0 and 14.
    
                            Some mice received MAC before intranasal
                            exposure on days 0 and 14
    
                            OVA challenge on days 35, 38 and 41
    
                            Sacrificed on day 42
                                 Natural-Resistance-Associated Macrophage
                                 Protein 1 (Nrampl): When exposed to only
                                 OVA, NrampIS evoked less of an antibody
                                 responses (IgE, lgG1 and lgG2a) compared to
                                 Nrampl RHowever when coexposed to OVA and
                                 EHC-93, the level of increased production of
                                 antibodies was similar in both groups. After
                                 coexposure, the wild-type showed increased
                                 histopathological lesions, whereas the
                                 macrophage-stimulation-deficient types showed
                                 only a slight increase (not significant). IL-4, IFN-
                                 Y, TNF-a and IL-5 levels were similar in wild-
                                 type and the Nrampl strains.
    
                                 Pretreatment with MAC: lgG2a concentration
                                 was increased further in the group pretreated
                                 with NAC. The wild-type mice and the NAC
                                 pretreated mice showed similar
                                 histopathological lesion patterns. IL-4 levels
                                 were similar in wild-type and the NAC pretreated
                                 mice. (IFN-y, TNF-a and IL-5 levels not
                                 reported)
    
                                 Inducible Nitric Oxide Synthase (iNOS): The
                                 wild-type and the iNOS-deficient mice had
                                 similar levels of increased IgE antibody
                                 production. The lgG1 and lgG2a antibody
                                 response was twice as great in the iNOS-
                                 deficient mice compared to the wild type. The
                                 wild-type and the iNOS-deficient mice showed
                                 similar histopathological lesions. No differences
                                 in BAL cells or cytokines were observed
                                 between the wild-type and iNOS-deficient mice.
    
                                 IL-4: The IL-4-deficient mice did not produce an
                                 increase in IgE or lgG1  antibodies, as was seen
                                 in the wild-type mice. The lgG2a antibody
                                 response in the IL-4-deficient mice was similar
                                 to the wild type response resulting in adjuvant
                                 activity for the lgG2a antibodies. Overall the
                                 histological response of the wild-type mice was
                                 greater compared to the IL-4 deficient mice.
                                 There was no real difference between the two
                                 strains observed in the BAL cells, except IL-5
                                 was significantly lower in the IL-4-deficient mice.
    December 2009
                                         D-146
    

    -------
         Study
                                   Pollutant
                     Exposure
                     Effects
    Reference:
    Stevens et al.
    (2008, 1553631
    
    Species: Mouse
    Strain: BALB/c
    
    Age: 10-12 wk
    
    Weight: 17-20 g
                      DE: generated using a 30 kW4-cylinder
                      Deutz BF4M1008 diesel engine
                      connected to a 22.3 kWSaylor Bell air
                      compressor. The engine was operated
                      on Diesel fue| purchased from a service
                      station in Research Triangle Park, NC.
                      The engjne wgs operated gt g steady.
    
                      s'a'e>  approx. 20% of engine's full load.
    
                      Hi9n composition:
    
                      02: 4.3 ± 0.07 ppm
    
                      NO: 9.2  ± 0.30 ppm
    
                      N02: 1.1 ±0.05 ppm
    
                      S02: 0.2 ±0.10 ppm
    
                      Low composition:
    
                      02, NO,  N02, S02 below detection limits
    
                      Particle Size: NR
    Route: Whole-body Inhalation
    
    OVA immunization and challenge: intranasal
    
    Dose/Concentration: High = 2000 pg/m3
    Low = 500 pg/m
    
    Time to Analysis: DE exposure for 4 h/day on
    days 0-4.
    
    OVA immunization 40 min after DE exposure on
    days 0-2
    
    Challenged on days 18 and 28.
    
    Sacrificed 4 h after last exposure of day 4 for gene
    set analysis or 18, 48, or 96 h after the last
    challenge
    IgE Antibody Production: In the absence OVA,
    IgE antibodies were not detected. 18, 48 and 96
    h following OVA, mice exposed to low and high
    doses of DE had an increase in antibodies over
    time. Mice exposed to high dose had an
    increase (non-significant) to the OVA exposed
    control at the 48 h time mark
    
    BAL Cells: Cell counts at 18 and 96 h after OVA
    treatment did not differ among treatment groups.
    At 48 h the number of eosinophils, neutrophils
    and lymphocytes were significantly increased in
    mice exposed to both high and low
    concentrations of DE. With DE exposure alone,
    only neutrophils were statistically increased in
    the high DE concentration. This indicates the
    combination exposure of DE and an antigen is
    essential to promote the development of allergic
    lung disease.
    
    BAL Cytokines: IL-6 production showed a
    dose-dependent and time-dependent increase,
    but was significantly increase in the  high dose
    group at 96 h. The high dose group saw a non
    significant increase in IL-10 levels over time.
    The greatest increase in IL-10 for the low dose
    group occurred18 h after OVA stimulation.
    
    Pulmonary Inflammation and Lung Injury: No
    differences among the groups were observed
    for macrophage, lymphocyte, neutrophil and
    eosinophil counts. Protein and LDH levels were
    not found to be increased in the BALF of any
    group.
    
    Gene Analysis: Pair wise comparisons
    revealed significant gene set difference between
    the high DE and control groups. Comparison of
    the high DE/OVA versus air/OVA showed
    significant changes in 23 gene sets, including
    genes involved in oxidative stress responses.
    The high DE/saline versus the air/saline showed
    significantly altered pathways. Altered pathways
    include those for cell  adhesion, cell cycle
    control, apoptosis, growth and differentiation,
    and cytokine signaling. The results show that
    relatively short exposures to DE cause mild
    increases in immunologic sensitization to
    allergen.
    December 2009
                                                                         D-147
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Takizawa et al.
    (2003, 1570391
    
    Species: Human
    
    Cell Lines: Normal
    Small Airway
    Epithelial Cells and
    Bronchial Epithelial
    Cells (BET-1A)
    Suspended DEP: collected using a
    2,300-cc Isuzu diesel engine using
    standard diesel fuel at 1,050 rpm under
    a load of 6 torque.
    
    DE exposure in vitro (air exposure):
    collected using a 2,300-ml Isuzu diesel
    engine at 1,050 rpm.
    
    Composition:
    
    Fine particles: 1  mg/m3
    
    CO: 10.6 ppm
    
    N02: 7.3 ppm
    
    S02: 3.3 ppm
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: Suspended DEP: varying
    doses from 0-50 pg/ml
    
    IL-13: varying doses from 0-25 ng/ml
    
    DE exposure in vitro (air exposure):  100 pg/m3
    
    Time to Analysis: Cells were exposed to varying
    concentrations of suspended DEP for up to 24 h.
    
    NF-KB: analyzed at 6 h after suspended DEP
    exposure
    
    Air exposure at 0, 2, 4,  8 or 14 h
    Preliminary experiments indicated that DEP at
    0.1- 50 |jg/mL had no significant cytotoxicity to
    BET-1A cells and human bronchial epithelial
    cells (as analyzed by LDH levels).
    
    Eotaxin Production: (Eotaxin is a cc
    chemokine that plays a role in eosinophil
    accumulation in a variety of allergic disorders)
    Epithelial and BET-1 A cells treated with
    suspended DEP or IL- showed a dose-
    dependent stimulatory effect on eotaxin release
    or production. Simultaneous exposure to 25
    ng/mL IL-13 and DEP depicted an additive effect
    for both cell types.
    
    Eotaxin mRNA: At 25 pg/mL, suspended DEP
    showed a time-dependent effect on eotaxin
    mRNA  levels up to 12 h in both cell types.
    Extracted RNAfrom human bronchial epithelial
    cells exposed to varying doses of DEP showed
    a dose-dependent effect for both cell types (up
    to 25 pg/mL DEP) on eotaxin mRNA levels after
    12 h of exposure. IL-13 also induced a dose-
    dependent increase on eotaxin mRNA levels in
    cells in  both cell types. Combination of IL-13
    and DEP showed an additive effect on mRNA
    levels in BET-1 A cells. DE exposure in vitro also
    showed a time-dependent stimulatory effect on
    eotaxin production in BET-1 A cells.
    
    NF-KB  / STAT6 Activation: (it has been
    suggested that NF-KB plays a role in the trans-
    criptional regulation of eotaxin gene expression)
    Cells exposed to 1-25 pg/mL DEP for 6 h
    increased NF-KB. BET-1 A cells treated with
    suspended DEP failed to activate STAT6.
    
    Effect of MAC and PDTC on Eotaxin mRNA
    Levels: (NAC and PDTC are antioxidant
    reagents with inhibitory effects on NF-KB
    activation) in  BET-1A, both NAC and PDTC
    showed a dose-dependent inhibitory effect on
    DEP-induced eotaxin production. Both reagents
    also blocked DEP-induced eotaxin mRNA levels
    in BET-1 A cells. NAC and PDTC did not
    suppress eotaxin production or eotaxin mRNA
    levels in IL-13 stimulated BET-1A cells. In
    addition pre-treatment with NAC attenuated NF-
    KB activation induced by DEP but had  no effect
    on STAT6 induction by IL-13.
    
    These findings suggest that DEP stimulated
    eotaxin gene expression via NF-KB dependent,
    but STAT6-independent, pathways.
    December 2009
                                                      D-148
    

    -------
         Study
                 Pollutant
                     Exposure
                                                                                                                          Effects
    Reference:
    Tesfaigzi et al.
    (2005,1561161
    
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    
    Age: 6 wk
                      PM: Wood smoke generated from a
                      conventional wood stove that has a
                      0.5m3 firebox and a sliding gate air
                      intake damper. The stove was operated
                      over a 3-phase burn cycle that spanned
                      6 h. Fire was started (initiated exposure)
                      with imprinted / unbleached  newspaper
                      and a mix of black and white oak.
    
                      Wood smoke components: organic
                      material, small amounts of EC and
                      metals and associated analytes.
    
                      Particle Size: 0.36 pm(MMAD)
                                         Route: Whole-body Inhalation
    
                                         Dose/Concentration: PM: 1000 pg/m3
    
                                         Time to Analysis: Exposed to wood smoke or
                                         filtered air 6 h/day for 70 consecutive days
    
                                         OVA IP injection immunization on days 2, 9
    
                                         OVA aerosol exposure 2 h/day on days 67-70
                                         following daily exposure to wood smoke or filtered
                                         air
    
                                         Sacrificed day 70
                                                  Body Weight and Respiratory Function: No
                                                  difference in clinical signs or body weight was
                                                  observed when comparing the two rat groups.
                                                  The wood smoke exposed group had a 45%
                                                  lower dynamic lung compliance when compared
                                                  to those exposed to the filtered air group before
                                                  the methacholine challenge. Challenging the
                                                  rats with methacholine caused a decrease in
                                                  dynamic lung compliance in both groups, but the
                                                  decrease was greater in the air-exposed group.
                                                  At the highest dose of methacholine, the
                                                  dynamic lung compliance in controls was similar
                                                  to the baseline value  of the smoke-exposed
                                                  group. No significant  differences in total
                                                  pulmonary resistance were observed. Wood
                                                  smoke exposed rats had a 10% increase in
                                                  functional residual capacity than the air-exposed
                                                  group.
    
                                                  BAL Cells and Cytokines: There was no
                                                  difference in lymphocyte, eosinophil or
                                                  neutrophils in the BALF of either group. There
                                                  was an increase, though not statistically
                                                  significant, in macrophages the wood smoke
                                                  exposed group when  compared to the filtered air
                                                  group. In the BALF, IFN-y and IL-1IS levels were
                                                  significantly decreased, IL-4 and GRO-a levels
                                                  were increased in rats exposed to wood smoke
                                                  compared to filtered air. Serum IgE levels
                                                  experienced a reduction trend in the wood
                                                  smoke group, but it did not reach significance.
                                                  Both groups showed  mild signs of inflammation.
                                                  The average eosinophils present in stained
                                                  tissue was 21 % higher in the wood  smoke ex-
                                                  posed group compared to the air exposed.
    Reference: Tomita
    et al. (2006,
    0978271
    
    Species: Mouse
    
    Gender: Female
    
    Strain: C57BL/6J;
    AHR-deficient;
    mEH-deficient;
    ARNT floxed (loxP
    sequences
    inserted in Arnt
    gene);
    Tcell-specific
    ARNT-deficient
    
    Age: 7 wk
    
    Weight: 20 g
    DEP: two independent preparations
    fractionated into 13 different fractions
    based on acidic and basic functionality
    (one from light-duty, 4-cylinder diesel
    engine using standard diesel fueled and
    other generated from A4JB-type, Isuzu
    automobile, Japan)
    Individual PAH tested (Osaka, Japan):
    BbF = benzo[b]fluoranthene
    BeP = Benzo e]pyrene
    IDP=lndeno1,2,3-cd]pyrene
    BpPe = Benzo[ghi]perylene
    BaP = Benzo[a]pyrene
    BkF = Benzo[k]fluoranthene
    Per = Perylene
    DBA= Dibenzo[a,h]anthracene
    
    Particle Size: NR
    Route: Intraperitoneal Injection
    
    Dose/Concentration: DEP, fractionated DEP or
    PAH compounds: 0.5 pg -10 mg/kg bw in 50 pi of
    olive oil
    
    Time to Analysis: Single, sacrificed 3 days post-
    exposure.
                                                                                                         Effect on Thymus: DEP treatment (10 mg/kg of
                                                                                                         body weight) caused severe atrophy of the
                                                                                                         thymus while the spleen and lymph nodes
                                                                                                         appeared normal. Three days following DEP
                                                                                                         treatment showed a marked reduction in thymus
                                                                                                         size. The total number of thymocytes was
                                                                                                         reduced  by more than 70% mostly due to a
                                                                                                         massive  reduction in DP cells (CD4+CD8+).
                                                                                                         DEP induced no significant alterations in the cell
                                                                                                         numbers of CD4/CD8 ratios in the spleen and
                                                                                                         lymph nodes.
    
                                                                                                         DEP Extracts: Only the WAC (carbonic acid
                                                                                                         fraction) and BE (weak basic fraction) did not
                                                                                                         produce a significant reduction in thymocyte
                                                                                                         numbers in vivo. Among the active fractions, 7
                                                                                                         produced a marked selective loss of immature
                                                                                                         DP thymocytes, similar to the crude extract of
                                                                                                         DEP.
    
                                                                                                         PAH Effects: Thymic involution was severely
                                                                                                         induced by the N and various other fractions. 7
                                                                                                         out of the 8 PAH compounds were significantly
                                                                                                         effective  in decreasing the number of
                                                                                                         thymocytes upon in vivo exposure. Only BpPe
                                                                                                         did not have an effect.
    
                                                                                                         AHR/ARNT and mEH Deficient Mice (BaP and
                                                                                                         DEP only): In the absence of AHR, BaP
                                                                                                         treatment did not result in a loss of thymocytes.
                                                                                                         Like DEP, BaP produced severe thymic
                                                                                                         involution in mEH-deficient mice.  DEP-mediated
                                                                                                         thymic involution was significantly enhanced in
                                                                                                         mEH-deficient mice.
    December 2009
                                                      D-149
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Verstraelen et al.
    (2005, 0968721
    
    Species: Human
    
    Tissue/Cell
    Types: Monocyte-
    derived dendritic
    cells (Mo-DC)
    
    Cord blood
    samples of seven
    women were
    collected from
    umbilical vessels
    of placentas of
    normal, full-term
    infants.
    DEP- SRM 2975
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: DEP in varying
    concentrations: 0.2, 2, 20, 200, 2000 ng/mL
    
    LPS100ng/mL
    
    Time to Analysis: 24 h
    Biological Markers: Exposure to DEP alone did
    not alter expression levels of HLA-DR,  CD86 or
    CD83.
    
    Treatment with IPS alone caused a non-
    significant increase in all three markers when
    compared to the control.
    
    Treatment with DEP+LPS caused a significant
    increase in the expression of CD83 and a non-
    significant increased expression of HLA-DR and
    CD86. DEP+ IPS induced a bell-shape dose-
    response curve on the expression of all three
    markers, with a dose of 20 ng/mL DEP + 100
    ng/mL IPS causing the largest increase in
    upregulation.
    
    When only the results of the LPS-responsive
    donors (5 out of 7 blood cord samples) were
    included,  the effects described above become
    more pronounced.
    Reference:
    Walczak-
    Drzewiecka et al.
    (2003, 1888031
    
    Species: Mouse
    
    Cell Line:
    C1.MC/C57.1
    (C57) Mast Cells
    Metal and Transition Metal Ions: Sr *,
    Ni2*, Cd2*, Al3*, Pb2*
    
    Particle Size: NR
    Route: Cell culture,
    
    Dose/Concentration: 0.1-5 pmol
    
    Time to Analysis: 10min-4h
    B-Hex Mediator Release in Mast Cells:
    Incubation with SrCI2, NiS04, CdCI2 or AICI3
    resulted in a 2-5% release of B-hexoaminidase
    in mast cells. Incubation with a mixture of all
    these compounds induced a greater (11%)
    release in B-hexoaminidase, indicating there
    might be a additive effect.
    
    Cell Viability: Incubation of cells at
    concentrations and incubation time employed
    did not result in decrease in cell viability.
    
    Antigen-Mediated Mediator Release in Mast
    Cells: Al3* and Ni2* enhanced antigen-mediated
    release. 10-7 M AICI3 released  23% of B-
    hexoaminidase compared to antigen alone,
    which induced 11 % release of B-
    hexoaminidase. Cd *, Sr * and  Pb * enhanced
    antigen-mediated release to a lesser extent.
    Ni2*, Al3*, Sr2* and Cd2* depicted a dose-
    dependent relationship with antigen-mediated B-
    hexoaminidase release.
    
    Antigen-Induced Protein Phosphorylation:
    Addition of the antigen induced the anticipated
    phosphorylation of multiple proteins in C57 mast
    cells The presence of Ni * and Pb * mediated an
    increase in phosphorylation of several of the
    proteins and Al3* mediated a decrease in
    phosphorylation of multiple proteins (specifically
    the 56 and 37 kD bands).
    
    Antigen-Mediated Cytokine Secretion (IL-4):
    At certain concentrations all tested metal and
    transition metal ions were able to induce IL-4
    secretion or enhance antigen-induced IL-4
    secretion in mast cells, but no dose-dependent
    relationship was established.
    Reference: Wan
    and Yu (2006,
    1571041
    
    Species: Human
    
    Cell Lines:
    Human, Bcell
    lymphocytes
    PMBC
    (>98.5% B cells-
    CD19+CD20+; <1
    % T cells (CD3+))
    
    Human lymphocyte
    cell lines -- DG75
    NQ01 wild type
    DEP from 4 cyl Isuzu diesel methanol
    extracts
    
    Particle Size: NR
    Route: Cell Culture, PMBC = 1 xio6 cell
    
    DG 75 = 3x106 cells
    
    lgEPMBC1xl06/mL
    B-cells 0.5x106/mL
    
    Dose/Concentration: 2.5, 5,10, 20 pg DEPX/
    plate (20 pg/mL)
    
    IgE DEPX 100 ng/mL
    sulfurophane at 0 - 30 pmol
    
    Time to Analysis:  6 h mRNA; 16 h protein assay.
    IgE 14 days.
    Induction of NQ01 by DEPX: In PBMCs and
    DG75DEPX dose-dependently induced NQ01
    mRNA expression NQ01 ARE was increased
    NAC inhibited NQ01 gene expression dose
    dependently. p38 MAPKand P13K inhibition
    partially blocked NQ01 mRNA and ARE
    induction  by DEPX.
    
    Induction of phase II  enzymes: DEPX induced
    IgE potentiation was reduced dose dependently
    by induced phase II  enzymes.
    December 2009
                                                      D-150
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:        DEP (light-duty, four-cylinder engine-
    Whitekus et al.     4JB1 type, Isuzu Automobile, Japan;
    (2002,1571421     standard diesel fuel) (extracts)
    
    Species: Mouse    Particle Size: NR
    
    Cell Line: RAW
    264.7
                                         Route: Cell Culture
    
                                         Dose/Concentration: 50 |jg/mL
    
                                         Time to Analysis: Exposed to antioxidants 5 h.
                                         HO-1 western blot, determination of cellular
                                         GSH:GSSG ratios, carbonyl protein content, lipid
                                         hydroperoxides performed.
                                                   DEP significantly reduced the GSH:GSSG ratio.
                                                   This effect was prevented by adding thiol
                                                   antioxidants MAC or BUG. DEP increased lipid
                                                   peroxide levels, but the addition of all
                                                   antioxidants decreased these levels. DEP
                                                   increased carbonyl groups. MAC, BUG, and
                                                   luteolin reduced HO-1 expression.
    Reference:
    Whitekus et al.
    (2002, 1571421
    
    Species: Mouse
    
    Gender: Female
    
    Strain: BALB/c
    
    Age: 6-8 wk
    
    Weight: NR
    DEP (light-duty, four-cylinder engine-
    4JB1 type, Isuzu Automobile, Japan;
    standard diesel fuel) (extracts)
    
    Particle Size: 0.5-4 pm
    Route: Inhalation
    
    Dose/Concentration: 200, 600, 2000 pg/m3
    
    Time to Analysis: Exposed 1 h/day, 10 days.
    Animals receiving OVA had 20 min OVA exposure
    after DEP exposure.
    DEP+OVA dose-dependently increased IgE and
    lgG1, being more effective than the OVA-alone
    treatment. This effect was significantly
    suppressed by thiol antioxidants NAG or BUG.
    DEP+OVA increased carbonyl protein and lipid
    peroxide over OVA. NAG or BUG suppressed
    lipid peroxide and protein oxidation. No general
    markers for inflammation were observed.
    Reference: Witten
    et al. (2005,
    0874851
    
    Species: Rat
    
    Gender: Female
    
    Strain: F344
    
    Age: 8 wk
    
    Weight: ~175 g
    DEP (heavy-duty Cummins N14
    research engine operated at 75%
    throttle)
    
    Particle Size: 7.234-294.27 nm
    Route: Nose-only Inhalation
    
    Dose/Concentration: Low- 35.3 ± 4.9 pg/m3, High-
    632.9 ± 47.61 pg/m3
    
    Time to Analysis: Exposed 4 h/day, 5 days/wk,
     3 wk. Pretreated with saline or capsaicin.
    There were no differences for substance P. The
    low-exposure group had significantly less NK1.
    DEP reduced NEP activity. Plasma extraversion
    dose-dependently increased and was greatest
    in capsaicin animals. Respiratory permeability
    dose-dependently increased. IL-1|3was
    significantly higher for the low-exposure group.
    IL-12 was significantly lower in the capsaicin
    high-exposure group. TNF-a increased in the
    high-exposure group and capsaicin low-
    exposure group. High exposure induced
    particle-laden AMs in the lungs, perivascular
    cuffing consisting of mononuclear cells, alveolar
    edema and increased mast  cell number.
    Neutrophil  and eosinophil influx was not seen.
    Reference: Wong
    et al. (2003,
    0977071
    
    Species: Rat
    
    Gender: Female
    
    Strain: F344/NH
    
    Age: ~4 wk
    
    Weight: ~175 g
    DEP (Cummins N14 research engine at
    75% throttle) (EC- 34.93-601.67 pg/m3,
    OC-1.90-11.25 pg/m3, Sulfates 0.94-
    17.96 pg/m3, Na- 4.07-4.78 ng/m3, Mg-
    0.60-0.86 ng/m3, Ca- 5.05-10.66 na/m3,
    Fe- 3.17-6.44, Cr- 0.68-1.31 ng/m3; Mn-
    0.11-0.22 ng/m3, Pb-0.97-1.24 ng/m3)
    
    Particle Size: 7.5-294.3 nm
    Route: Nose-only Inhalation
    
    Dose/Concentration: Low- 35.3 + 4.9 pg/m3, High-
    669.3 ± 47.6 pg/m3
    
    Time to Analysis: Exposed 4 h/day, 5 days/wk,
     3 wk. Pretreated with saline or capsaicin.
    DEP dose-dependently increased plasma
    extraversion, which was further increased by
    capsaicin. In the high-exposure group, particle-
    laden AMs (which were reduced by capsaicin),
    inflammatory cell margination, perivascular
    cuffing with subsequent mononuclear cell
    migration and dispersal,  increased mast cells,
    and decreased substance P were all seen. NK-
    1R was downregulated in the low-exposure
    group and upregulated in the capsaicin-
    pretreated high-exposure group. NEP
    decreased significantly for both groups.
    December 2009
                                                       D-151
    

    -------
         Study
                 Pollutant
                     Exposure
                     Effects
    Reference:
    Yanagisawa et al.
    (2006, 0964581
    
    Species: Mouse
    
    Gender: Male
    
    Strain: ICR
    
    Age: 5 wk
    
    Weight: 25-28 g
    Washed DEP (carbonaceous core),
    DEP-OC(extracted organic chemicals)
    and Whole DEP
    
    Particles collected from: 4JB1-Type,
    four-cylinder, 2.74 L, Isuzu diesel
    engine, while operated on standard
    diesel fuel at 200 g under a load of 10
    torques.
    
    Particle Size: 0.4 pm(MMAD)
    Route: IT Instillation
    
    Dose/Concentration: 50 pg/0.1L
    
    1. Control-0.1mL PBS
    2. DEP-OC- 50 pg
    3. Washed DEP- 50 ug
    4. Whole DEP- 50 ug DEP-OC + 50 ug Washed
    DEP5. OVA-1 pg =
    6. DEP-OC-1  pg + OVA
    7. Washed DEP- 50 pg + OVA 8. Whole DEP- 50
    pg DEP-OC +  50 pg Washed DEP + OVA
    
    Time to Analysis: All groups received OVA or PBS
    every 2 wk for 6 wk and the PM component or PBS
    once a week for 6 wk.
    BALF Cells: DEP-OC + OVA caused a
    significant increase in PMN infiltration in the
    BALF compared to the control. Exposure to
    Whole DEP+ OVA caused PMN count to rise
    further. OVA alone DEP-OC +OVA, Washed
    DEP + OVA and Whole DEP + OVA all caused a
    significant increase in macrophages com pared
    to the control.
    
    Lung Histology: Exposure to OVA, Washed
    DEP, DEP-OC and Whole DEP caused a slight
    increase in PMNs, mononuclear cells and goblet
    cell proliferation. Treatment with all three DEP
    groups + OVA caused a significant increase in
    mononuclear cells, PMNs and goblet cell
    proliferation. Whole DEP + OVA had the
    greatest impact.
    
    Th1 and Th2 Cytokine  Expression: Washed
    DEP+OVA caused a significant increase  in IFN-
    Y compared to control, whereas Whole
    DEP+OVA caused a significant decrease
    compared to control. No significant differences
    in IL-2 and IL-4 levels were seen among  groups.
    DEP-OC+ OVA and Whole DEP+  OVA caused
    significant increases in IL-5 compared to control
    and compared to OVA Whole DEP+OVA caused
    significant increase in IL-13 compared to control
    
    Eotaxin and MIP-1o Expression: OVA
    increased eotaxin levels and DEP-OC+OVA
    caused a more significant increase in eotaxin.
    Whole DEP alone caused a significant increase
    in MIP-1a and  Whole DEP+OVA caused an
    even greater increase in MIP-1a.
    
    lgG1 Levels: Exposure to DEP-OC+OVA
    caused an increase in lgG1 and exposure to
    Whole DEP+OVA caused greater  elevation  in
    lgG1 levels.
    Reference: Yang
    et al. (2003,
    0878861
    Species: Mouse
    
    Gender: Female
    
    Strain: B6C3F1
    
    Age: 6-8 wk
    DEP-SRM 1650
    
    Particle Size: 0.5 pm(MMAD)
    Route: IT Aspiration
    
    Dose/Concentration: 1, 5, or 15 mg /kg
    
    Time to Analysis: 3 times in 2 wk or 6 times in
     4wk.
    Toxicity of DEP Exposure: DEP did not have a
    significant effect on body, liver or spleen weight.
    The highest dose of DEP caused an increase in
    lung weight and lung weight relative to body
    weight. None of the hematological parameters
    were significantly different in the mice exposed
    for 2 wk; in the 4 wk group there was a
    significant decrease in platelet counts in mice
    exposed to 15mg/kg.
    
    Exposure on Spleen IgM AFC: DEP exposure
    for 2 wk induced a dose-dependent decrease in
    spleen AFC in response to sRBC immunization.
    Mice exposed to 15 pg/kg depicted a 35%
    reduction in total spleen activity.  In the group
    exposed to DEP for 4 wk, the decrease in AFC
    was not significantly different than the control.
    
    DEP  Exposure on Spleen Cell
    Number/Lymphocyte Counts: Exposure for 2
    or 4 wk did not affect total number of nucleated
    splenocytes. DEP caused a 30% reduction  in
    total T cells. The number of B cells were not
    significantly affected.
    
    DEP  Exposure on Spleen T-Cell Function:
    (evaluated in  2 wk exposure group only) DEP
    induced a dose-dependent decrease in spleen
    cell proliferation to ConA. DEP did not affect
    spleen cell proliferation in response to anti-CD3
    mAb. Production of IL-2 in response to ConA
    was reduced  in a dose-dependent manner by
    DEP  exposure.  IFN-y production was decreased
    by exposure to DEP. IL-4 production was not
    measured.
    December  2009
                                                     D-152
    

    -------
         Study
                                   Pollutant
                     Exposure
                     Effects
    Reference: Yin et  DEP = SRM 2975 (NIST)
    al. (2005, 0881331  Listeria
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    (BN/CrlBR)
    
    Age: NR
    
    Weight: 200-250 g
                      Particle Size: NR
                                                           Route: Nose-only inhalation (DEP), IT instillation
                                                           (Listeria)
    
                                                           Dose/Concentration: 100,000 CPU (Listeria); 21.2
                                                           ± 2.3 mg/m3 (DEP)
    
                                                           Time to Analysis: DEP exposure for 4 h/day for 5
                                                           days; infection with Listeria 7 days post-exposure;
                                                           sacrifice 3 and 7 days postinfection
                                                  Lung Deposit: Estimated mean lung deposit of
                                                  DEP = 406 + 29 pg/rat DEP prolonged growth of
                                                  bacteria in lung
    
                                                  Alveolar Macrophage (AM) Response: DEP
                                                  significantly inhibited Listeria-induced IL-1|3
                                                  secretion at day 7 and TNF-a and IL-12 at both
                                                  day 3 and day 7 IL-10 production was enhanced
                                                  at day 7.
    
                                                  T-Lymphocyte Response: DEP significantly
                                                  reduced the development of T cells in response
                                                  to Listeria infection. These lymphocytes
                                                  displayed increased production  of IL-6 at day 7,
                                                  but significantly diminished levels of IL-10, IL-2
                                                  and IFN-y.
    Reference: Yin et  DEP = SRM 2975 (NIST)
    al. (2004, 0976851  Listeria
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    (BN/CrlBR)
    
    Age: NR
    
    Weight: 200-250 g
                      Particle Size: NR
                                                           Route: Inhalation (DEP), IT instillation (Listeria)
    
                                                           Dose/Concentration: 20.62 + 1.31 mg/m3 (DEP).
    
                                                           100,000 CPU Listeria
    
                                                           Time to Analysis: DEP exposure for 4 h/day for 5
                                                           days; inoculation with bacteria 2 h postexposure;
                                                           sacrifice 3, 7,10 days postinfection
                                                  Lung Deposit: Estimated mean lung deposit of
                                                  DEP = 389 ± 25 pg/rat
    
                                                  Pulmonary Responses and Bacterial
                                                  Clearance: DEP significantly augmented
                                                  Listeria-induced PMN infiltration, lung CPU and
                                                  recoverable AM at all times post-infection. LDH
                                                  activity was increased 3 days post-infection.
                                                  Bacterial count in DEP exposed rats remained
                                                  significantly higher through day 7.
    
                                                  Cytokine Production by AM: DEP exposure
                                                  significantly lowered Listeria-induced production
                                                  of IL-1P, TNF-a and IL-12. Production of IL-10
                                                  was strongly augmented.
    
                                                  T-lymphocyte Responses: DEP moderately
                                                  but not significantly lowered the total number of
                                                  lymphocytes, CD4+ cells and lymphocyte IL-10
                                                  production. Listeria-induced T-celi development
                                                  was strongly inhibited, as were the development
                                                  of CD8+ cells, IL-12 production and IFN-Y
                                                  secretion. DEP and Listeria exposure showed
                                                  and increased production of IL-6 at day 3 and
                                                  day 7 post-exposure.
    Reference: Yin et   DEP = SRM 2975
    al. (2007,1989801   eDEP = organic DEP extract
                      wDEP = washed DEP
                      CB = carbon black
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    (BN/CrlBR)
    
    Age: NR
    
    Weight: 225-250 g
    
    Cell Line: AM
                      Particle Size: DEP: median diameter-
                      19.4 pm, surface area- 91 m2/g; CB: 0.1-
                      0.6 pm
    Route: IT Instillation of Listeria; Cell Culture
    (2.5x105 cells/well)
    
    Dose/Concentration: DEP: 10, 50,100 pg/mL;
    CB: 50 |jg/mL
    
    Time to Analysis: Sacrifice 7 days postinfection or
    no infection. Cell culture: 1, 4,16, 24 h.
    AM Phagocytosis: None of the DEP or CB
    treatments were cytotoxic or affected the
    number of adherent cells. 10-100|jg/mL DEP
    significantly decreased AM phagocytosis in a
    concentration- and time-dependent manner,  with
    increased concentration and time decreasing
    activity.
    
    Bacterial Activity: The inhibition of AM
    bactericidal activity by DEP was time- and
    concentration-dependent. eDEP and wDEP
    inhibited the AM bactericidal activity but were
    less effective than DEP. The CB treatment was
    not significant.
    
    Cytokine Secretion by AM: DEP and eDEP
    concentration-dependently decreased TNF-a,
    IL-1B and IL-12, but increased IL-10.  wDEP  and
    CB did not show a significant effect.
    
    Cytokine Secretion by Lymphocytes: DEP
    and eDEP concentration-dependently
    decreased IL-2 and IFN-y. wDEP and CB had
    little effect, except high concentrations of wDEP
    decreased IFN-y.
    December 2009
                                                                        D-153
    

    -------
         Study
                 Pollutant
                     Exposure
                                                                   Effects
    Reference: Yin et
    al. (2004, 0879831
    
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    (BN/CrlBR)
    
    Age: NR
    
    Weight: 225-250 g
    
    Cell Line: AM
    DEP = SRM2975
    eDEP = organic DEP extract
    wDEP = washed DEP
    CB = carbon black
    
    Particle Size: DEP- NR, CB- 0.1-0.6 pm
    Route: IT Instillation of Listeria; Cell Culture
    Dose/Concentration: 50 pg/mL (DEP or CB)
                                                  DEP-lnduced ROS Production: ROSwas
                                                  induced by DEP or eDEP and inhibited by eDEP
                                                  with ANF or NAC. eDEP induction of ROS was
    Time to Analysis: Killed 7 days postinstillation. AM  Dependent. wDEP or CB did not induce
    isolated then incubated. DEP treatments for up to
    24 n                                          DEP-lnduced HO-1  Expression: DEP- or
                                                  eDEP-induced HO-1 expression was inhibited
                                                  by ANF, NAC or SB203580. wDEP or CB did not
                                                  induce ROS.  DEP or eDEP exposure resulted in
                                                  a 2.5- to 3-fold induction of HO-1  expression in
                                                  uninfectedAM.
    
                                                  eDEP-Modulated Cytokine Production: eDEP
                                                  exposure resulted in a time-dependent increase
                                                  in LPS-stimulated IL-10 or TNF-a production,
                                                  and both were inhibited by ANF or NAC. wDEP
                                                  did not affect  either. SOD pretreatment
                                                  attenuated eDEP-upregulated HO-1  expression,
                                                  inhibited IL-10, and reversed eDEP inhibition of
                                                  IL-12. Znpp decreased IL-10.
    Reference: Yin et   DEP = SRM 1650a
    al. (2003, 0961271
                      L. monocytogenes
    Species: Rat
    
    Gender: Male
    
    Strain: Brown-
    Norway
    (BN/CrlBR)
    
    Age: NR
    
    Weight: 200-250 g
    Particle Size: NR
    Route: Nose-only Inhalation (DEP); IT Instillation
    (Listeria)
    
    Dose/Concentration: 50 or 100 mg/m3 (DEP);
    100,000 bacteria per 500 pL sterile saline (Listeria)
    
    Time to Analysis: DEP exposure for 4 h. Bacterial
    inoculation. Sacrificed 3, 7 days post-exposure.
                                                  Lymphocyte Population: DEP-alone exposure
                                                  increased total lymphocytes, T cells and T-cell
                                                  subsets. Elevated cell counts in the combined
                                                  exposure were DEP dose-dependent, with the
                                                  100 mg/m  treatment having significant
                                                  increases in the cell number and CD8+/CD4+
                                                  ratio.
    
                                                  IL-2: DEP exposure in noninfected rats at both
                                                  doses increased IL-2 in the 24 h culture and
                                                  decreased IL-2 in the 48 h culture. The increase
                                                  in IL-2 at 3 days postinfection was not
                                                  significant. DEP exposure increased IL-2Ra in
                                                  response to ConA stimulation. DEP-treated
                                                  infected rats had increases in ConA-inducible
                                                  CD4+/IL-2RQ+ and CD8+/ IL-2Ra+.
    
                                                  IL-6: IL-6 production was dose-dependent in
                                                  DEP-treated uninfected rats and infected rats.
                                                  The combined exposure produced less IL-6 than
                                                  the DEP-alone or Listeria-alone treatments.
    
                                                  IFN-y: DEP decreased IFN-y at 3 days post-
                                                  exposure, but increased at 7 days post-
                                                  exposure in a dose-dependent manner.
                                                  Uninfected DEP-treated rats did not
                                                  substantially respond to HKLM. HKLM-induced
                                                  IFN-y production is strongly inhibited at all
                                                  tested DEP doses.
    Reference:
    Zelikoffetal.
    (2003, 0390091
    
    Species: Rat
    
    Gender: Male
    
    Strain: F344
    
    Age: 7-8 mo
    
    Weight: NR
    CAPS (concentrated ambient PM25 from
    New York City)
    S.pneumoniae
    
    Particle Size: 0.4 pm(MMAD)
    Route: Nose-only Inhalation (CAPS); IT Instillation
    (S.pneumoniae)
    
    Dose/Concentration: CAPS: Study 1- Mean- 345
    pg/m ; 60-600 pg/m . .Study 2- Mean-107 pg/m  ;
    65-150|jg/m3
    
    (S.pneumoniae 2-4*107)
    
    Time to Analysis: Study 1: Uninfected rats
    exposed to air or CAPS for 3 h. Sacrificed 3, 24, or
    72 h post-exposure or IT instilled 4, 24, 72,120 h
    and sacrificed 4, 24, 72 h postinfection
    Study 2: Infection with bacteria. Exposed 48 h later
    to CAPS or filtered air for 5 h. Sacrifice 9,18, 24,
    72,120 h post-exposure.
                                                  Study 1: CAPS did not effect cell numbers,
                                                  viability, profiles, lavageable LDH activity, total
                                                  protein, or total circulating WBC counts.
                                                  Exposure to CAPs prior to infection significantly
                                                  increased PMN  and decreased lymphocytes.
                                                  WBC levels returned to control levels by 4  h
                                                  postinfection. CAPS had  no effect on circulating
                                                  monocyte values. CAPS significantly increased
                                                  bacterial burdens at 24 h, but thereafter the
                                                  burden decreased to below control levels.
    
                                                  Study 2: In CAPS exposed rats, PMN
                                                  decreased, Pam increased, and the cytokines
                                                  TNF-a, IL-1|3and IL-6 decreased. Lymphocytes
                                                  and monocytes were unaffected. Bacterial
                                                  burdens in CAP-exposed rats were about 10%
                                                  greater than air  controls at 9 h and >300%
                                                  greater at 18 h.  CAPS significantly increased
                                                  the percent of affected lung area and severity of
                                                  infection.
    December 2009
                                                      D-154
    

    -------
         Study
                  Pollutant
                          Exposure
                                 Effects
    Reference:
    Zelikoffetal.
    (2002, 0377971
    
    Species: Rat
    
    Gender: Male
    
    Strain: Fischer
    344
    
    Age: 7-9 mo.
    
    Weight: NR
     Ambient NYC PM
    
     Single transition metals of Fe, Mn,
    
     Streptococcus pneumoniae
    
     Particle Size: NYC PM: PM2 5
    
     Fe2*'Mn2*, Ni2*: 0.4 pm (MMAD)
         Route: Nose-only Inhalation, IT instillation (S.
         pneumoniae)
    
         Dose/Concentration: Single metals/NYC PM: 65-
         90 pg/m3; 15-20x106 (S.pneumoniae)
    
         Time to Analysis: Infection/no infection followed
         by 5 h exposure to NYC PM or single transition
         metal. Sacrifice 4, 5, 9,18, 24, and 120 h after
         exposure.
                CAPs exposure to infected rats significantly
                increased pulmonary bacterial burdens of S.
                pneumo in a time-dependent manner. At 9 h,
                 18 h, 24 h, and 5 days after CAPs exposure,
                bacterial burdens were 10%, 300%, 70% and
                30% above controls. Uninfected rats exposed to
                the single transition metals showed significant
                alterations in PMNs and lymphocytes values at
                1 h post-exposure.
    
                Exposure to Fe of uninfected rats significantly
                increased superoxide anion production by
                pulmonary macrophages. Uninfected rats
                exposed to inhaled Fe significantly reduced B-
                lymphocyte proliferation at 48 h, but did not
                affect T-lymphocyte production. Inhaled Ni, for
                the uninfected, significantly decreased T-
                lymphocyte production at 18 h, and did not
                affect B-lymphocyte production. Inhalation of Fe
                by infected  rats facilitated an increase in
                bacterial numbers while Ni inhibited bacterial
                clearance. Inhaled Fe by infected also
                significantly decreased PMNs and lymphocyte
                numbers by 35% and increased pulmonary
                macrophage numbers by 29% when compared
                to the air exposed group. Results demonstrated
                that inhalation of Fe altered innate and adaptive
                immunity in uninfected hosts, and both Fe and
                Ni reduced  pulmonary bacterial clearance in
                previously infected rats.
    Reference: Zhong  CAPs: Concentrated Air Particles
    et al. (2006,        (Boston, MA)
    0932641
    	            Urban air particles (UAP)SRM1649
    Species: Mouse    (Washington, DC)
    Gender: Male
    
    Strain: BALB/c
    
    Age: 6-8 wk
    
    Weight: NR
    
    Cell Line:
    J774A.1, IFN-y-
    primedAMs,
    unprimedAMs
     Ti02
    
     Carbon Black (CB) (Sigma, St. Louis,
     MO)
    
     Streptococcus pneumoniae: strain
     ATCC6303
    
     Particle Size: UAP = NR;
     Ti02/CB = NR;CAPs:
    -------
    Reference
    Reference:
    Campbell et al.
    (2005, 0872171
    Species: Mouse
    Strain: BALB/c
    
    Age: 7 wk
    Reference: Che
    et al. (2007,
    0964601
    Species: Rat
    Strain: SD
    Gender: Male
    and Female
    Age: 9 wk
    Weight: 190-
    220 g
    Reference:
    Kleinman et al.
    (2008, 1900741
    Species: Mouse
    Gender: Male
    Strain: ApoE"'"
    Age: 6 wk
    Weight: NR
    Reference: Liu
    et al. (2005,
    0886501
    Species: Rat
    Strain: Wistar
    Gender: Male
    Age: 8 wk
    Reference:
    Sirivelu et al.
    (2006, 1111511
    
    Species: Rat
    
    Gender: Male
    
    Strain: Brown
    Norway
    Age: 12-13 wk
    Pollutant
    CAPs from Los Angeles, lacking
    reactive organic and H20 soluble
    gases, 03, NOX, SOX
    Particle Size: F+UF: <2.5 pm;
    UF:<0.18|jm
    
    
    Gasoline exhaust (collected from
    1996 Guangzhou passenger car
    with Dongfeng Gasoline Series 155
    kw engine and no exhaust catalytic
    converter fuelled with 90-octane Pb-
    free gasoline from China
    Petroleum).
    Particle Size: NR
    
    
    
    CAPs (Los Angeles, CA) (OC, EC =
    -50%; sulfate, nitrate -11%)
    Particle Size: NR
    
    
    
    
    CAPs from Taiyuan, China
    Particle Size: <2.5|jm
    
    
    
    CAPs from Grand Rapids, Ml
    
    Particle Size: <2.5|jm
    
    
    
    
    
    
    
    
    Exposure
    Route: Whole-body Inhalation
    Dose/Concentration: 20-fold
    concentration of near highway ambient air,
    avg UF concentration: 282.5 pg/m3, avg F
    concentration: 441. 7 pg/m3
    Time to Analysis: 4 h/day, 5 days/wk for 2
    wk
    Route: IT Instillation
    Dose/Concentration: 5.6, 16.7, or 50.0
    L/kg, final volume 0.3 mL/rat
    Time to Analysis: 1/wk for 4 wk; 24 h post
    -instillation.
    
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: High dose: Mass
    concentration- 114.2 pg/m3, Low dose:
    Mass concentration: 30.4 pg/m3
    Time to Analysis: 5 h/day, 3days/wk, 6
    wk; 24 h postexposure.
    
    
    Route: IT Instillation
    Dose/Concentration: 0, 1.5, 7.5, or 37. 5
    mg/kg, final volume 0.2 mL/rat
    Time to Analysis: 24 h
    
    
    Route: Whole-body Inhalation
    
    Dose/Concentration: 500 pg/m3
    
    Time to Analysis: 8h; assayed at 24-h PE
    
    
    
    
    
    
    Results
    Mice were challenged with OVA prior to exposure and 1 and 2
    wk following exposure, and then brains were assayed. F+UF
    and UF exposure increased NF-KB DNA binding in brain. TNF-
    a increased with F+UF. IL-1a increased with UFand F+UF.
    This suggests a possible link between PM exposure and
    neurodegenerative disease processes.
    
    
    A dose-dependent increase was observed in brain DNA
    damage starting at 5.6 L/kg. Increase in lipid peroxidation and
    carbonyl protein was also observed at 50 L/kg. Decrease in
    brain SOD occurred at all exposures. GPx activity was
    unchanged with exposure. This suggests an association
    between gasoline exhaust and oxidative damage to the brain.
    
    
    
    
    Activated AP-1 dose-dependently increased. Activated NF-KB
    significantly increased with the high CAPs dose. GFAP (which
    represented activated astrocytes) and activated JNK
    significantly increased with the low CAPs dose.
    
    
    
    
    In the brain, SOD and CAT activity were significantly
    decreased at the 2 highest doses; GSH levels were
    significantly decreased at the highest dose. This suggests an
    association between PM exposure and oxidative damage
    mediated by prooxidant/antioxidant imbalance or high levels of
    free radicals.
    
    
    PVN: CAPs alone or with OVA increased NE.
    
    MPA: CAPs increased Da when treated with OVA while no
    changes in NE, 5-HIAA and DOPAC were observed.
    
    Arcuate nucleus: OVA sensitization increased NE levels.
    
    OB: CAPs and OVA increased NE levels, but no changes in
    Da, DOPAC, or 5-HIAA were observed.
    Other areas: No differences in other areas of hypothalamus,
    substantia nigra, or cortex were observed. CAPs alone or with
                                                                                             OVA increased serum corticosterone. These results suggest
                                                                                             that CAPs can cause region-specific modulation of
                                                                                             neurotransmitters in brain and that the stress axis may be
                                                                                             activated causing aggravation of allergic airway disease.
    Reference:
    Veronesi et al.
    (2005, 0874811
    
    Species: Mouse
    
    Strain: ApoE"'" or
    C57BI/6
    
    Age: Young
    adults
    CAPs from Tuxedo, NY
    
    Particle Size: <2.5|jm
    Route: Whole-body Inhalation
    
    Dose/Concentration: Average daily
    concentration 113|jg/m3
    
    Time to Analysis: 6 h/day, 5days/wk for 4
    CAPs-exposed ApoE" mice had an 29% reduction in TH-
    stained neurons and a 8% increase in GFAP staining
    compared to air-exposed ApoE"'". No differences were see in
    C57 mice. The results suggest that ApoE" mice, characterized
    by increased brain oxidative stress, are susceptible to PM-
    induced neurodegeneration.
    December 2009
                                                        D-156
    

    -------
    Reference
    Reference: Win-
    Shwe et al.
    (2008, 1901461
    Species: Mouse
    Gender: Male
    Strain: BALB/c
    Age: 7 wk
    Weight: NR
    Reference:
    Zanchi et al.
    (2008, 1571731
    Species: Rat
    Gender: Male
    Strain: Wistar
    Age: 45 days
    Pollutant
    DEP (Nanoparticle-rich - NPDE; 81-
    diesel engine, steady-state
    condition, 5 h/d, 2000rpm, 0 Nm)
    (CO, C02, NO, N02, S02)
    Particle Size: 26.21 + 1. 50 nm
    (diameter)
    
    
    ROFAfrom Universidade de Sao
    Paulo, Brazil
    Particle Size: 1.2 + 2.24pm
    (MMAD)
    
    
    Exposure
    Route: Whole-body Inhalation
    Dose/Concentration: 148.86 + 8.44 pg/m3
    Time to Analysis: 5 h/day, 5 days/wk,
    4 wk. Some mice ip injected with
    lipoteichoic acid (LTA) 1*/wk, 4wk. Morris
    water maze behavioral test: 3 days
    acquisition, 2 day probe trial.
    
    
    Route: Intranasal Instillation
    Dose/Concentration: 20 pg/10 pi saline
    Time to Analysis: 30 days
    
    
    Results
    Mice in the LTA+NPDE group had significantly longer mean
    escape latencies, indicating impaired acquisition of spatial
    learning. NPDE directly increased NR1 and TNF-a.
    LTA+NPDE increased NR2A, NR2B, and IL-lp, however LTA
    was primarily responsible for the increases.
    
    
    Exposed rats had increased lipid peroxidation in striatum and
    cerebellum. This could be reversed with N-acetylcysteine
    treatment. ROFA treatment altered motor activity shown by
    decreased general exploration and peripheral walking, and
    was not prevented by NAC. Results suggests that chronic
    ROFA induces behavioral changes and brain oxidative stress.
    
    
    Table D-6.     Reproductive and developmental effects.
       Reference
    Pollutant
    Exposure
    Effects
    Reference: Fedulov  DEP
                                       Route: Intranasal Instillation
                                                                           DEP increased BAL PMN counts in normal and pregnant mice.
                                                                                   '  '   —   •--		   IL-6
    Species: Mouse
    Gender: Female
    (pregnant),
    Offspring: NR
    Strain: BALB/c
    Age: NR
    Weight: NR
    Reference: Fujimoto
    et al. (2005, 0965561
    Species: Mouse
    Strain: Sic: ICR
    Gender: Females
    (pregnant mice and
    fetuses)
    Age: NR (pregnant
    females), 14 days of
    gestation (fetuses)
    Reference:
    Hougaard et al.
    (2008, 1565701
    Species: Mouse
    Strain: C57BI/6
    Gender: Pregnant
    females, male and
    female offspring
    Age: 12, 16 wk
    (female offspring),
    13, 17 wk (male
    offspring)
    Carbon black (CB)
    Ti02
    Particle Size: NR
    DE: generated by 2369
    ccdiesel engine at 1050
    rpm at 80% load with
    commercial light oil
    Particle Size: 0.4 |jm
    (MMAD)
    DEP(SRM2975)
    Particle Size: 90 m2/g
    (SA)
    Dose/Concentration: DEP, Ti02: 50 pg in 50 pL,
    50 pg/mouse; CB: 250 pg in 50 pL
    Time to Analysis: Particle samples baked 3 h.
    Protocol 1a: Pregnant mice treated with DEP or
    Ti02. Analyzed 1 9 or 48 h later. Protocol 1 b:
    Pregnant mice DEP, Ti02 or CB treated day 14 of
    pregnancy. 4 day-old offspring i.p. injected with
    OVA+alum. 12-14 days-old exposed aerosolized
    OVA.
    Route: Inhalation
    Dose/Concentration: 0.3, 1.0 or 3.0 mg DEP/m3
    Time to Analysis: 1 2 h/day, 7 days/wk from 2 day
    post coitum to 13 dpc. Sacrificed 14 dpc. mRNA
    expression examined in female fetuses.
    Route: Whole-body Inhalation
    Dose/Concentration: 20 mg DEP/m3
    Time to Analysis: Exposed 1 h/dayfrom gestation
    days 7-19. Mice separated for behavioral testing
    on PND 22 (day of delivery is PND 0). Behavioral
    testing at 12, 16 wk for female offspring and 13,
    1 7 wk for male offspring.
    and KC compared to nonpregnant controls. Offspring of DEP,
    CB or Ti02 exposed mice had increased AHR and airway
    inflammation. Ti02 exclusively altered the expression of 80
    genes in pregnant mice.
    Significant increase in absorbed placentas were observed in
    the 0.3 and 3.0 concentration. A decrease in absorbed
    placentas was observed for the 1 .0 concentration. Increased
    inflammatory cytokine mRNA in placentas from exposed
    offspring were observed. An increased number of absorbed
    placentas in DE-exposed offspring were seen.
    Body weight of exposed unchanged at birth. Body weight
    decreased at weaning.
    Unchanged dams & pups at weaning. At 2 mo, exposed female
    pups required less time to locate platform in spatial Reversal
    task of Morris Water maze.
    December 2009
                                      D-157
    

    -------
        Reference
                              Pollutant
                                                                Exposure
                                                                                                                   Effects
    Reference:
    Hougaard et al.
    (2008, 1565701
                        DEP (SRM 2975)
    
                        Particle Size: 240 nm
                        (MMAD); surface area 90
    Species: Mouse      mg /g, density 2.1 g/cm'
    
    Gender: Female
    (pregnant),
    Offspring- male,
    female
    
    Strain: C57BL/6
    
    Age: NR
    
    Weight: NR
                                               Route: Inhalation
    
                                               Dose/Concentration: 19.1 + 1.13 mg DEP/m3
    
                                               Time to Analysis: Pregnant dams exposed GD 7-
                                               19,1 h/day. GD 20 named PND 0 for pups.
                                               Weights recorded,  1 pup from each group
                                               sacrificed PND 2. Weights recorded PND 9. PND
                                               22 1 male and female removed from each group
                                               for behavioral testing. Dams and remaining
                                               offspring sacrificed PND 23 or 24.
                                                                                           DEP females gained more weight during gestation. Generally,
                                                                                           DEP pups weighed less. No significant DNA damage was
                                                                                           measured, but DEP caused slightly higher IL-6, MCP-1, and
                                                                                           MIP-2. Plasma thyroxin levels as well as learning and memory
                                                                                           were similar amongst the groups.
    Reference: Huang
    et al. (2008, 1565741
    
    Species: Rat
    
    Gender: Male
    (adults), male and
    female (fetuses)
    
    Strain: Wstar
                        ME: Motorcycle Exhaust
                        (generated from 1992
                        Yamaha cabin motorcycle
                        with two-stroke 50 cc
                        engine).
    
                        Particle Size: NR
                                               Route: Nose-only Inhalation
    
                                               Dose/Concentration: 1: 10and 1: 50 dilutions
    
                                               Time to Analysis: 2 h/day (1 h in morning and 1
                                               h in afternoon), for 5 consecutive days/wk, for 4
                                               wk (1 :50,  1 :10 dilutions) and 2 wk (1 :10 dilution).
                                               Male mated with untreated females. Pregnant
                                               females sacrificed on 20 days of gestation. Male
                                               and female fetuses observed.
                                                                                           After exposure, decreased body weight and testicular
                                                                                           spermatid number were observed. 1: 10 ME exposure for 4 wk
                                                                                           (no recovery) decreased testicular weight and increased the
                                                                                           inflammatory cytokine mRNA. Glutathione system and lipid
                                                                                           peroxidation were not affected.
    Age: 8 wk (male
    adults), 20 days of
    gestation (fetuses)
    Reference:
    Lichtenfels et al.
    (2007, 0970411
    Ambient air in Sao Paulo,
    Brazil
    Particle Size: NR
    Route: Ambient Air Exposure
    Dose/Concentration: NA
    Time to Analysis: Males housed in
    Decreased testicular, epididymal sperm counts, decreased
    number of germ cells, and decreased elongated spermatids
    were observed. Decreased SSR, and a sex ratio shift (fewer
    open top males) also occurred after exposure.
    Gender: Male and
    Female
    
    Strain: Swiss
    
    Age: NR
                                               chambers for 24 h/day, everyday for 4 mo,
                                               beginning 10 days after birth. Males mated to non-
                                               exposed females immediately following exposure.
                                               Males sacrificed immediately following mating.
                                               Pregnant females remain in chamber and
                                               sacrificed on 19 days of pregnancy.
    Reference: Mauad
    et al. (2008, 1567431
    
    Species: Mouse
    
    Gender: Male,
    Female
    
    Strain: BALB/c
    
    Age: 10 days
    
    Weight: Parental:
    21.4 + 4.0-26.3 +
    2.8 g; 15 day-old
    offspring: 7.8+ 1.1 -
    9.0+ 1.0 g; 90 days-
    old offspring: 20.3 +
    2.3-27.4+1.8 g
                        PM (busy traffic street
                        Sao Paulo, Brazil; Aug.
                        2005-April 2006) (N02,
                        S02, CO)
    
                        Partjc|e size: 2.5, 1 0 pm
                        (diameter)
                                               Route: Ambient Air Exposure                    Mild foci of macrophage accumulations containing black dots
                                                                                            of carbon pigment occurred in the alveolar areas on 90 day-old
                                               Dose/Concentration:JM25: filtered chamber- 2.9  mice  Surface-to-volume ratio decreased from 15 to 90 days of
                                                                                            age anc|was hjgner jnmjce exp0sec| to air pollution. PM
                                                                                            exposure reduced inspiratory and expiratory volumes at higher
                                                                                            levels of transpulmonary pressure.
                                               + 3.0 pg/m3, nonfiltered chamber- 16.9 + 8.3
                                               pg/m3; Outdoor concentration: PM10-36.3+ 15.8
                                               pg/m3, CO- 1.7 + 0.7 ppm, NO- 89.4 + 31.9 pg/m3,
                                               S02- 8. 1+4.8 pg/m3
                                               Time to Analysis: Nonfiltered exposure 24 h/day
                                               for 4 mo. Mated at 120 days exposure. After birth,
                                               30 females and offspring transferred to filtered or
                                               nonfiltered chamber. Killed 15 or 90 days of age.
    Reference:
    Mohallem et al.
    (2005, 0886571
    
    Species: Mouse
    
    Strain: BALB/c
    
    Gender: Female
    
    Age: 10 wk, 10 days
                        Filtered or ambient air in
                        downtown Sao Paulo
                        situated at crossroads
                        with high traffic density
                        (predominant source of
                        Partic|e size: NR
                                               Route: Whole-body Inhalation
    
                                               Dose/Concentration: PM10: 35.5 + 12.8 pg/m3;
                                               CO: 2.2 + 1.0 ppm; N02:107.8 + 42.3 pg/m3; S02:
                                               11.2+ 5.3 pg/m3
    
                                               Time to Analysis: Exposed for 24 h/7days/wk for
                                               4 mo.  Newborns mated after reaching
                                               reproductive age of 12 wk. All pregnant females
                                               sacrificed between 19th and 20th day of
                                               pregnancy.
                                                                                           No effects in adult exposed animals. Increased implantation
                                                                                           failure of neonatal exposed-dams.
    
                                                                                           Sex ratio, # of pregnancies, resorbtions, fetal deaths, and fetal
                                                                                           placenta Weights unchanged after neonatal ambient air
                                                                                           exposure.
    December 2009
                                                                        D-158
    

    -------
    Reference
    Reference: Mori et
    al. (2007, 0965641
    Species: Mouse
    Strain: C57/BL
    
    Gender: Male
    Age: 6 wk
    Reference: Ono et
    al. (Ono et al, 2007,
    1560071
    Species: Mouse
    Strain: ICR
    Gender: Pregnant
    females, male
    offspring
    Age: NR (pregnant
    females), 12wk
    (offspring)
    Reference: Ono et
    al. (Ono et al, 2007,
    1560071
    Species: Mouse
    
    Strain: ICR
    
    Gender: Male
    offspring, Pregnant
    females
    Age: 12 wk (male
    offspring)
    Reference:
    Pinkerton et al.
    (2004, 0874651
    Species: Rat
    Gender: Female
    (pregnant),
    Offspring- NR
    Strain: SD
    Age: 10 days (pups),
    Pregnant females-
    10- 14 days of
    gestation
    Pollutant
    DEP: generated by 4-
    cylinder diesel engine
    Particle Size: NR
    
    
    
    
    DE: generated from 4-cyl
    diesel Isuzu engine at
    1500rpm using standard
    diesel fuel.
    Particle Size: NR
    
    
    
    
    
    
    
    DE: generated from 4JB-
    2type, light duty 3060 cc
    4-cyl Isuzu diesel engine
    under 1 500 rpm
    Particle Size: NR
    
    
    
    
    
    
    
    PM (Fe and soot from
    combustion of acetylene
    and ethylene in a laminar
    diffusion flame system)
    Particle Size: Median
    diameter: 72-74 nm; size
    range: 10-50 nm
    
    
    
    
    
    
    Exposure
    Route: Dorsal Subcutaneous Instillation
    Dose/Concentration: 0.2 ml (of 1. 1 mg/ml or 0.37
    mg/ml)
    Time to Analysis: 2*/wk for 10wk; 1 wk post last
    instillation.
    
    
    Route: Inhalation
    Dose/Concentration: NR
    Time to Analysis: Exposed from 2 day post
    coitum to 16 dpc. Parameters for male offspring
    measured on days 8, 16, 21, 35, 84 and sacrificed
    at 84 days.
    
    
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: 1.0 mg DEP/m3
    Time to Analysis: Pregnant females exposed
    from 2 day postcoitum- 16 dpc. Without
    undergoing further exposure, male offspring
    sacrificed at 12wk.
    
    
    
    
    
    Route: Inhalation
    Dose/Concentration: Mean mass concentration:
    243 + 34 pg/m3; Average Fe concentration: 96
    fjg/m
    Time to Analysis: Exposed 10 days postnatal
    age, 6 h/day, 3 days (consecutive).
    Bromodeoxyuridine injected 2 h before necropsy. .
    
    
    
    
    
    Effects
    cDNA library screen after sub-cutaneous injection identified
    activated clones related to prostanoids and arachadonic acid
    (Platg2c2c, Acsl6) and sperm production (Stk35). However, the
    route of exposure was unconventional.
    
    
    
    
    PND 8 and 16 male reproductive accessory gland weight
    decreased. PND 21 decreased serum testosterone (T); PND
    84 increased serum T. FSHr, sTAR mRNA decreased PND 35
    and 84. Relative testis and epididymal weight unchanged.
    Sertoli cell degeneration observed.
    
    
    
    
    
    
    
    Dose-dependent increase in seminiferous tubule degeneration
    and decreased DSP. After 1 mo recovery, DSP recovered at
    the lowest dose.
    
    
    
    
    
    
    
    
    
    A significant reduction of cell proliferation occurred only within
    the proximal alveolar region of exposed animals compared to
    controls. There were no significant differences between the
    groups for alveolar formation and separation within the
    proximal alveolar region
    
    
    
    
    
    
    
    
    Weight: NR
    Reference: Silva et
    al. (Silvaetal.,
    2008,166981)
    
    Species: Mouse
    
    Strain: Swiss
    
    Gender: Females
    (pregnant mice)
    
    Age: 1st, 2nd,  3rd
    wk of pregnancy
    (females), GD19
     fetuses)
    Ambient air: Sao Paulo,
    Brazil
    
    Particle Size: NR
    Route: Ambient Air Exposure
    
    Dose/Concentration: NR
    
    Time to Analysis: 1stwk, 2ndwk, Srdwk
    or combo of exposure during pregnancy.
    Decreased fetal weight with exposure in 1st wk of pregnancy.
    
    Decreased placental weight with exposure in any of the 3 wk of
    pregnancy.
    December  2009
                                                   D-159
    

    -------
    Reference
    Reference: Somers
    et al. (2002, 0781001
    Species: Mouse
    Strain: Swiss
    Webster
    
    Sender: Male and
    Female
    Age: 6-8 wk (adult
    male and females), 5
    days (pups)
    Reference: Somers
    et al. (2004, 0780981
    Species: Mouse
    Gender: NR
    Strain: Sentinal Lab
    Age: NR
    Weight: NR
    Reference:
    Sugamata et al.
    (2006, 1570251
    Species: Mouse
    
    Strain: ICR
    Gender: Pregnant
    -emales, male and
    emale offspring
    \ge: 11 wk
    offspring), NR
    pregnant females)
    Reference: Tozuka
    et al. (2004, 0908641
    Species: Rat
    
    Strain: F344
    
    Sender: Pregnant
    emales, male and
    emale fetuses
    Age: Gestation day
    20 (fetuses), NR
    (pregnant females)
    Reference: Tsukue
    et al. (2004, 0966431
    Species: Mouse
    Strain: Sic: ICR
    Sender: Pregnant
    emales, female
    fetuses
    Age: Gestation day
    14 (fetuses)
    Pollutant
    Ambient air: 2 sites in
    Canada (polluted
    industrial area 1km
    downwind from two
    integrated steel mills &
    rural location 30 km
    gywgw\
    
    Particle Size: NR
    
    
    
    PM (rural or urban-
    industrial)
    Particle Size: >0.1 pm
    
    
    
    
    DE
    Particle Size: NR
    
    
    
    
    
    
    
    
    
    DE: generated by diesel
    engine (309 cc Model
    NFAD-50)
    
    Particle Size: NR
    
    
    
    
    
    
    DE: generated by 2369
    cc Isuzu diesel engine
    operating at 1 050 rpm
    with 80% load and using
    commercial light oil.
    Particle Size: NR
    
    
    
    
    Exposure
    Route: Ambient Air Exposure
    Dose/Concentration: NR
    Time to Analysis: Exposed 24 h/day, 7 days/wk
    for 10 wk from September 10, 1999- November
    21, 1999. Exposed to clean air for 6 wk post-
    treatment. Paired with mice within exposure
    group. 5d old pups measured.
    
    
    
    Route: Ambient Air Exposure
    Dose/Concentration: Mean TSP: Rural- 16.2 +
    8.3-31.7+13.2 pg/m3, Urban-Industrial- 38.9 +
    10.5 -115.3 + 25.3 pg/m3
    Time to Analysis: Exposed 1 0 wk. Bred 9 wk
    postexposure.
    
    
    Route: Inhalation
    Dose/Concentration: 0.3 mg DEP/m3
    Time to Analysis: Pregnant females exposed
    from 2 day post coitum to 16 dpc. Offspring
    sacrificed 11 wk after birth.
    
    
    
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: 1.73mg/m3
    
    Time to Analysis: Exposed 6 h/day from GD 7-20
    with no exposure on Saturdays or Sundays (4
    non-exposure days total). Fetuses and maternal
    blood collected on GD20. PAHs: Exposed 6 h/day
    from GD 7-14 with no exposure on Saturdays or
    Sundays. Breast milkcollected PND14.
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: 0.1 mg DEP/m3 (at 1:8
    dilution with clean air)
    Time to Analysis: Exposed for 8h/day from 2 day
    postcoitum to 13 dpc (with no exposure on days 4,
    5, 11, 12). Sacrificed 14 dpc. Only female fetuses
    studied.
    
    
    
    Effects
    ESTR germ line mutations following exposure.
    Heritable mutation rate increased 1 .5 to 2 fold in urban vs.
    rural site. Increased frequency is paternal line dependent.
    
    
    
    
    
    The offspring of urban-industrial mice inherited paternal ESTR
    mutations 1.9-2.1 times more than rural or HEPA-filtered
    offspring. Maternal ESTR mutations were not significant.
    
    
    
    
    Exposed pups had increased caspase 3 positive cells and
    decreased purkinjie cell number (cerebellum), similar to human
    Autism brain phenotype.
    
    
    
    
    
    
    
    
    
    Gestational and lactational exposure to DE'sAnd PAHs. 7 milk
    PAHs increased in DE-exposed dams. DE exposure can lead
    to PAH pup exposure through breast milk.
    
    
    
    
    
    
    
    
    SF-1 & MISmRNAdid not change. Other steroidogenic genes
    were also unchanged. BMP-15 and oocyte differentiation
    mRNA decreased.
    
    
    
    
    
    
    December 2009
    D-160
    

    -------
    Reference
    Reference: Tsukue
    et al. (2002, 0305931
    Species: Mouse
    Strain: C57/BL
    
    Gender: Females,
    male and female
    offspring
    Age: 6 wk, 70 days
    post natal (offspring)
    Reference: Ueng et
    al. (2004, 0961991
    Species: Mouse
    Gender: Female
    
    Strain: Wistar
    Age: 21 days
    Cell Line: MCF-7
    Reference: Veras et
    al. (2008, 1904931
    Species: Mouse
    Gender: Male,
    Female
    Strain: BALB/c
    Age: 20 days,
    newborns
    Weight: NR
    Reference: Veras et
    al. (2009, 1904961
    Species: Mouse
    Gender: Male,
    Female
    Strain: BALB/c
    Age: 20 days
    Weight: NR
    Reference:
    Watanabe (2005,
    0879851
    Species: Rat
    Gender: Female
    (pregnant),
    Offspring- male
    
    Strain: F344/DuCrj
    Age: 7 days of
    gestation - parturition
    (females), 96 days
    (offspring)
    Weight: 240-262 g
    (offspring)
    Pollutant
    DE: generated by light-
    duty, 4-cyl Isuzu diesel
    engine at 1500 rpm.
    Particle Size: NR
    
    
    
    
    
    ME: generated from a
    Yamaha Cabin
    motorcycle 2-stroke 50-
    cc engine and variable
    venture carburetor
    Pflrtirlp ^170* MR
    ralUUIC wltd INf\
    
    
    PM (downtown Sao
    Paulo, Brazil near
    crossroads with high
    traffic density, 67% PM2 5
    comprises air pollution)
    Particle Size: 2.5 |jm
    (diameter)
    
    
    PM (Sao Paulo, Brazil;
    near crossroads with high
    traffic density) (Al, Ca,
    Cu, Fe, K, Na, Ni, P, Pb,
    S, Si, Ti, V, Zn, C)
    Particle Size: 2.5 |jm
    (diameter)
    
    
    DE (309cc engine, Model
    NFAD50, Yanmar Diesel
    Co., Osaka, Japan,
    1800rpm, 45% load) (PM,
    N02)
    Particle Size: 90% <0.5
    pm
    
    
    
    
    
    
    
    
    Exposure
    Route: Whole-body Inhalation
    Dose/Concentration: 0.3, 1.0 or 3.0 mg DEP/m3
    Time to Analysis: Exposed 12 h/day, 7 days/wk
    for 4 mo. Some females sacrificed immediately
    following exposure. Remainder mated with
    unexposed males. Parameters measured in
    offspring at postnatal day 70.
    
    
    Route: Intraperitoneal Instillation. Cell Culture.
    Dose/Concentration: IP: 1, 10, 50 pg/ml
    Cell Culture: 0.01, 0.1, 1, 10, 50, 100 pg/ml
    
    Time to Analysis: IP: 1/day for 3 days and
    sacrificed on 24 day. Cell Culture: 3, 24, 30, 48 h
    and 2 days.
    
    Route: Open-Top Chamber
    Dose/Concentration: PM25- 27.5 pg/m3; N02-
    101 pg/m ; CO- 1.81 pg/m ; S02- 7.66 ppm
    Time to Analysis: 20 days-old mice maintained in
    filtered or nonfiltered chamber until 60 days-old.
    Offspring maintained in respective chambers until
    21 days-old. Offspring mate at 60 days-old.
    Females euthanized 18th GD.
    
    
    Route: Open-Top Chamber
    Dose/Concentration: Mean: Non-filtered- 27.5
    pg/m , Filtered- 6.5 pg/m
    Time to Analysis: 20 days-old mice maintained in
    filtered or non-filtered chamber. Allowed to mate at
    60 days. 2 generation model.
    
    
    Route: Inhalation
    Dose/Concentration: High dose total group: PM-
    1.71 pg/m3, N02- 0.79 ppm; Low dose total group:
    PM- 0.17 pg/m3, N02- 0.10 ppm
    Time to Analysis: Pregnant rats exposed
    gestational day 7 to delivery 6 h/day. 5 groups:
    high dose total DE, high dose PM, N02 filtered,
    low dose total DE, low dose PM, N02 filtered,
    clean air control. Offspring sacrificed day 96 after
    birth.
    
    
    
    
    
    Effects
    DE-exposed females had decreased uterine weight at 4 mo.
    Offspring had decreased body weight at 6 and 8 wk of age.
    Decreased rate of good nesting construction (3 mg/m3).
    AGO decreased In males (30 and 70 days old).
    
    Organ weight decreased in females and female crown to rump
    length decreased.
    
    
    10 mg/kg +E2 induced anti-estrogenic uterine effects and
    antiestrogenic with in vitro (MCF-7 cells) E2 screen.
    
    
    
    
    
    
    Fetal weight and maternal blood space volume and surfaces
    declined in the groups exposed to nonfiltered air. Fetal
    capillary surfaces were greater in nonfiltered air groups. There
    was a significant gestational effect on maternal :fetal surface
    ratios with values declining significantly in groups exposed
    during pregnancy to nonfiltered air. The total oxygen diffusive
    conductance of the intervascular barrier increased significantly
    during pregestational exposure to nonfiltered air. Mass-specific
    conductance increased during pregestational and gestational
    periods of exposure to nonfiltered air.
    
    
    Ambient air pollution extended the estrus cycle, which reduced
    the number of cycles. Antral follicles decreased. Mating time
    increased and fertility and pregnancy indices decreased. The
    mean post-implantation loss rate increased, which was
    influenced by both pre- and post-gestational exposure. Fetal
    weight decreased and was also influenced by pre- and post-
    gestational exposure, which exhibited a significant interaction.
    
    
    All groups had significantly less daily sperm production than
    the control. PM and N02 in DE decreased spermatogenia but
    was not significant, however the high dose PM filtered group
    achieved significance. Pachytene cells, spermatids, and Sertoli
    cells were lower in all groups compared to the control.
    
    
    
    
    
    
    
    
    
    
    December 2009
    D-161
    

    -------
        Reference
          Pollutant
                     Exposure
                           Effects
    Reference: Yauk et
    al. (2008, 1571641
    
    Species: Mouse
    
    Strain: C57BL/6x
    CBA F1 hybrid
    
    Gender: Male
    
    Age: 7-9 wk
    HEPA-Filtered air (PM    Route: Ambient Air Exposure
    removed) and ambient air
    at 2 sites               Dose/Concentration: NR
    
    -2 km from two integrated Time to Analysis: Parameters measured 3,10
    steel mills              wk, or 10 + 6 wk recovery following exposure.
    
    -1 km from major
    highway on Hamilton
    Harbor
    
    Components:
    
    Metals 3.6 + 0.7  pg/m3
    
    TSP9.4+17|jg/m3
    
    Particle Size: NR
                                                 10+6 wk exposure induced increased ESTR mutations in
                                                 sperm DMA of exposed v filtered. No testicular DMA adducts
                                                 seen in exposed males. At 3 wk DMA increased adducts seen
                                                 in lungs of exposed males, not in filtered males. Mutations
                                                 were PM dependent, and gas-phase independent.
    Reference: Yokota
    et al. (2009, 1905181
    
    Species: Mouse
    
    Gender: Female
    (pregnant), Male
    (offspring)
    
    Strain: ICR
    
    Age: NR
    
    Weight: NR
    DE (2369-cc diesel
    engine, Isuzu Motors,
    Ltd..Tokyo,  Japan; 1050
    rpm, 80% load,
    commercial  light oil)
    
    Particle Size: NR
    Route: Inhalation. Pre-natal Exposure
    
    Dose/Concentration: DE: 1.0 mg/m3; CO: 2.67
    ppm, N02: 0.23 ppm, S02: <0.01 ppm
    
    Time to Analysis: Pregnant mice exposed 8 h for
    5 days from GD 2-17. Mothers and pups kept in
    clean room. Pups weaned on PND 21 then
    transported to Tokyo University of Science. 2wk
    acclimation. Exposed 12 h light/dark cycle. Activity
    monitor with infrared ray sensor measured
    spontaneous motor activity (SMA), 10 min
    intervals 2 days. After behavioral test, mice
    decapitated.
    Prenatal DE exposure decreased SMA in the male offspring.
    DE decreased locomotor activity during the light phase.
    Dopamine levels in the striatum and nucleus accumbens did
    not change, but HVA concentrations decreased in DE-exposed
    mice.
    Reference: Yoshida   DEjgenerated from a 4-
    et al. (2006,1561701  cyl, 2300 cc diesel Isuzu
                        engine at 1050 rpm and
    Species: Mouse      80o/0 |oad).
                           Route: Whole-body Inhalation
    
                           Dose/Concentration: 0.1 mg DEP/m3
    
                           Time to Analysis: Exposure on 2-13 days of
                                                 Responses to exposure showed strain-related variations with
                                                 ICR as the most sensitive followed by C57 and ddY as the
                                                 least sensitive. MIS mRNAexpression, a factor in male
                                                 gonadal differentiation, was significantly decreased in the ICR
    Strain: ICR,
    C57BI/6J or DDY
    Gender: Pregnant
    Females, Male
    fetuses
    Age: 14 days of
    gestation (fetuses),
    2-13 days of
    gestation (pregnant
    females)
    Reference: Yoshida
    et al. (2006, 0970151
    Species: Mouse
    Strain: ICR
    Gender: Pregnant
    females and male
    offspring
    
    Age: 2-1 6 days
    postcoitum (pregnant
    females), 28 days
    (male offspring)
    Particle Size: NR
    
    
    
    
    
    
    
    
    DE: generated by 4Jb1-
    type, light duty 4-cylinder
    Isuzu diesel engine using
    standard diesel fuel at
    1500 rpm.
    Particle Size: NR
    
    
    
    
    
    
    
    gestation. Parameters measured on 14 days of
    gestation.
    
    
    
    
    
    
    
    
    Route: Whole-body Inhalation
    Dose/Concentration: 0.3, 1.0 or 3.0 mg DEP/m3
    Time to Analysis: Pregnant females exposed 12
    h/days, 7 days/wk from 2-16 days postcoitum.
    Offspring sacrificed on postnatal day 28.
    
    
    
    
    
    
    
    ana uo; strains. Amor/ar- 1 expression was signmcanny
    decreased in the ICR strain only.
    
    
    
    
    
    
    
    
    NOAEL 0.3 mg DEP/m3.
    DE exposure induced increased reproductive gland weight
    (two higher doses) in male mice. mRNA decreases in
    aromatase and 3 p-hD (3.0 mg DEP/m3).
    No change in sex ratio. Two higher doses induced significant
    increased reproductive organ weights.
    
    Male pup weight Increased at PND 28. Increased serum T was
    observed in pups exposed to LOrng DEP/m3.
    
    Serum T positively correlated with DSP, testis weight, steroid
    enzyme mRNA.
    
    Reference: Yoshida   DE
    et al. 2004 (2004,
    0977601
    Species: Mouse
    
    Gender: Female
    (pregnant),
    Offspring- male
    
    Strain: ICR
    
    Age: 4, 6 wk
    
    Weight: NR
    Particle Size: NR
    Route: Inhalation
    
    Dose/Concentration: 6wk-old males, embryos:
    0.3,1.0, 3.0 mg DEP/m , Pregnant mice: 0.1, 3.0
    mg DEP/m3
    
    Time to Analysis: 6 wk-old males: Exposed 12
    h/day, 6 mo. 1 mo clean air exposure. Pregnant
    mice: Exposed 2-13 p.c. 8 h/day. Male embryos:
    Exposed 2-16 p.c. Examined at 4 wk-old.
    6wk-old Males: In the seminiferous tubules, DE dose-
    dependently caused degenerative and necrotic changes,
    desquamation of the seminiferous epithelium, and loss of
    spermatozoa. Spermatogenesis was still inhibited after a 1 m
    clean air exposure.
    
    Pregnant Mice: Ad4BP/5F-1 and MIS mRNA significantly and
    dose-dependently decreased in male fetuses exposed to DE.
    
    4wk-old Male Newborns: Tissue weight of the testis and
    accessory reproductive glands were significantly greater in DE-
    exposed mice. Blood testosterone concentration was 8X
    higher than the control at 1.0 mg DEP/m3. No significant
    differences occurred for testosterone synthetase mRNA.
    December 2009
                                                    D-162
    

    -------
    Table D-7.    Mutagenic/genotoxic effects in bacterial cultures.
    Reference
    Reference:
    Binkova et al.
    (2007, 1562731
    Species:
    Salmonella (+S9
    (rat liver))
    
    Cell Line: Calf
    thymus DMA
    Reference: Brits
    et al. (2004,
    0873971
    
    Species: S.
    typhimuriam
    Strain: TA98 ±
    S9 (Ames);
    TA104recN2-4
    andTA104pr1
    (Vitotox)
    Cell Line:
    Human whole
    blood (Comet,
    MN assays)
    Reference:
    Brown et al.
    (2005, 0959191
    Species: S.
    typhimuriam
    
    Strain:TA98
    Cell Line: Rat
    hepatomaH4IIE
    Reference:
    Bungeretal.
    (2006, 1563031
    
    Species:
    Salmonella
    typhimuriam
    
    Strain: TA98, TA
    100
    
    
    
    Reference:
    Bungeretal.
    (2007, 1563051
    
    Species:
    Salmonella
    typhimuriam
    Strain: TA98, TA
    100
    
    Pollutant
    PM (Prague, Kosice, Sofia,
    Czech Republic; summer,
    winter) (organic extracts)
    Particle Size: Diameter: <10
    pm
    
    
    
    
    PM (Flanders, Belgium;
    urban, rural, industrial sites)
    (organic extracts)
    
    Particle Size: 10pm
    (diameter)
    
    
    
    
    
    
    
    
    PM (New Zealand, summer,
    winter) (extracts)
    Particle Size: 10pm
    (diameter)
    
    
    
    
    
    DEP (diesel fuel (DF), low-
    sulfur diesel fuel (LSDF),
    rapeseed oil methyl ester
    (RME), and soybean oil
    methyl ester (SME)) (SOF-
    soluble organic fractions)
    Particle Size: Total particulate
    matter (no OCC) (gh-1): Mean
    DF- 4.0 ±0.2; 2.8 ±0.5; 1.8 +
    0.0; 3.4 ±0.2; 1.2 ±0.1
    
    
    Diesel engine emissions
    (DEE)-rapeseed oil (RSO)
    and rapeseed methyl ester
    (RME, biodiesel), natural gas
    derived synthetic fuel (GTL),
    and diesel fuel (DF)
    (SOF- soluble organic
    fractions)
    Particle Size: NR
    Exposure
    Route: Cell Culture
    
    Dose/Concentration: 100 pg EOM/mL
    Time to Analysis: PM collected 24 h daily 3
    mo, extracted. 24 h incubation BaP, c-PAH,
    EOM, with or without S9. 32P-Postlabeling
    4h. Autoradiography 1-24h.
    
    
    Route: Cell Culture
    Dose/Concentration: 2.5, 5, 10, 20m3 air
    equivalents/ml
    Time to Analysis: Air samples extracted.
    Ames assay 48 h. Vivotox test. Comet assay
    24 h. MN assay.
    
    
    
    
    
    
    
    Route: Cell Culture
    Dose/Concentration: 9.7-20.8 pg/m3
    (summer), 21.8-61 pg/m (winter)
    
    Time to Analysis: Air samples collected 15
    days, extracted. Ames test: Bacteria growth
    12 h, incubated 24 h. Hepatoma bioassay:
    24 h incubation 2x. EROD assay.
    
    Route: Cell Culture
    Dose/Concentration: Log 2 dilutions of
    extracts: 1.0, 0.5, 0.25, 0.125
    Time to Analysis: SOF extracted 12 h.
    Plates incubated 48 h.
    
    
    
    
    
    
    Route: Cell Culture
    Dose/Concentration: Log 2 dilutions of
    extracts: 1.0, 0.5, 0.25, 0.125
    Time to Analysis: SOF extracted 12 h.
    Plates incubated 48 h.
    
    Effects
    DNA adducts in EOM treatments were greater with S9 than
    without. Positive correlations were found between the amount of
    DNA adducts and the PAH content (notably BaP) in the EOM
    treatment.
    
    
    
    
    
    Ames: S9 induced mutagenicity of all extracts from all areas in a
    dose-dependent manner. Without S9, only extracts from the urban
    and industrial areas were mutagenic at the highest dose.
    
    Vitotox: Extracts were toxic at the highest dose.
    Comet: Significant DNA damage in the extracts was seen and
    enhanced by S9.
    MN: A dose-response relationship was seen in the urban extracts
    for increased micronucleated binuclear cells.
    
    
    
    
    
    Generally, the mutagenic rate was positively correlated to PM10, as
    well as PAH and BaP. PMi0 levels were higher and more
    mutagenic in winter than summer.
    
    
    
    
    
    
    No OCC: Without oxidation catalytic converter (OCC), DF extract
    produced the highest number of revertant colonies at all load
    modes in both TA98 and TA100 ± S9. RME, SME, and LSDF
    extracts caused lower or no mutagenic effects, seen especially at
    partial load modes and idle motion.
    OCC: Wth OCC, all extracts reduced the number of revertant
    colonies in TA98 and TA100 ±S9 at partial load modes B, C, and
    D. At load mode A (rated power), there was an increase of the
    number of revertant colonies in all assays -S9, significant for
    extracts from RME (TA98, TA100) and SME (TA98). S9 lowered
    frequency of mutations. At load mode E (idling), number of
    revertant colonies of DF extracts increased ±S9.
    Compared to DF, RSO significantly increased mutagenic effects of
    particle extracts (i.e., revertants) by 9.7-59 in TA98 and by 5.4-
    22.3 in TA100. (mRSO, RSO with lowered viscosity and fuel
    preheating in tank, produced highest number of revertant colonies
    in both strains ±S9.) RSO fuels condensates had 13.5 times
    stronger mutagenicity than DF. RME extracts had moderate but
    significantly higher mutagenic response in TA98 +S9 and TA100
    -S9. Effects of GTL did not differ significantly from DF.
    
    December 2009
    D-163
    

    -------
      Reference
            Pollutant
                  Exposure
                             Effects
    Reference: de
    Koketal. (2005,
    0886561
    
    Species: S.
    typhimurium
    
    Strain: TA98
    (with and without
    rat liver S9)
    
    Cell Line:
    Salmon testis
    DMA
    TSP (Total suspended
    particulate, Maastricht, The
    Netherlands; PMi0 and PM25
    from 6 urban locations with
    different traffic intensities.)
    
    (organic extracts)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: Mutagenicity assay:
    2.5, 9, or 18m3 sampled air in 100 pL DMSO;
    DMA adduct assay: 5 pL DMSO containing
    PMio or TSP from equivalent 50m3 sampled
    air. PM25 concentration equivalent to 35m3
    sampled air.
    
    Time to Analysis: Mutagenicity assay: Cells
    incubated 1 h with extracts. DMA adduct
    assay:  DMA incubated 4 h with extracts.
    Overall, the direct mutagenicity and DMA reactivity of PM25
    extracts were higher compared to PM10 and TSP. S9 generally
    reduced mutagenic activity in TA98 but increased reactivity to
    Salmon testis DMA. Total PAH and total carcinogenic PAH levels
    correlated with the mutagenicity of TSP and the S9-mediated
    mutagenicity of PM2 5. Neither transition metal composition nor
    radical generating capacity of PM correlated with mutagenic
    potential. Total PAH and carcinogenic PAH levels from PMio and
    PM25 correlated with direct and S9-mediated DNAadducts; for
    TSP these levels correlated with  direct DMA reactivity only.
    Reference:
    DeMarini et al
    (2004, 0663291
    
    Species:
    Salmonella
    
    Strain: TA98,
    TA98NR.TA98/1,
    8-DNP6,
    YG1021,
    YG1024, TA100
    A-DEP and forklift DEP (SRM
    2975)
    
    DEP (EOM)
    
    Particle Size: 0.4 pm (mean
    diameter)
    Route: Cell Culture
    
    Dose/Concentration: 0, 0.25, 0.5,1.0, 2.0
    EOM pg/plate
    
    Time to Analysis: DEPs sonicated 20min.
    Centrifuged 10 min. Organic material
    extracted and concentrated. Ames assay.
    Incubated 3 days.
    A-DEPs were more mutagenic in both TA98 and TA100 than SRM
    2975. There was 22x more PAH-related and 8-45x more
    nitroarene-related activity.
    Reference: El     PM (Jeddah, Saudi Arabia; 11
    Assouli et al.      sites, urban, winter) (organic
    (2007,1869141    extracts)
    Species: S.
    typhimuriam
    
    Strain: TA98
    (±S9)
    Particle Size: 10pm
    (diameter)
                                Route: Cell Culture
    
                                Dose/Concentration: 2.5, 50, 100 pg/plate;
                                EOM range: 6-40 pg/m3
    Time to Analysis: 24 h air samples,
                                             PAHs varied from 0.83 to 0.18 ng/m . Only 2 locations of heavy
                                             petrol driven cars showed strong genotoxic responses. A
                                             correlation existed between DMA damage and the amount of
                                             pollutants and PAHs. Toxicity and mutagenicity occurred only in
                                             the presence of S9. Only 3 of the 11 sites exhibited moderate
                                                               . Comet  mutagenic activities.
                                assay. 48 h incubation. Ames assay.
    Reference: Endo  PM (Tokyo, Japan; winter)      Route: Cell Culture
                                                                        Mutagenicity tests showed dose-response relationships that were
    et al. (2003,
    0972601
    
    Species: S.
    typhimuriam
    Strain: YG1024
    (±S9)
    Reference:
    Erdingeretal.
    (2005, 1564231
    Species: S.
    typhimurium
    
    Strain: TA98.
    TA100, TA98NR
    Reference: Iba et
    al. (2006,
    1565821
    
    Species: S.
    typhimuriam
    Strain: TA98,
    TA100(±S9(rat
    liver))
    Reference: Liu et
    al. (2005,
    0970191
    
    Species: S.
    typhimurium
    Strain: YG1024,
    YG1029
    Cell Line:
    Chinese hamster
    lung V79 cells
    (organic extracts)
    Particle Size: Diameter:
    >12.1 -0.06>|jm; Bimodal
    mass concentration: 1-2 pm
    
    
    PM (Baden-Wurttemberg,
    Germany; urban, 8 locations,
    glass fiber filters) (organic
    extracts)
    Particle Size: NR
    
    
    
    PM (wood smoke (WS) (New
    Jersey) and cigarette smoke
    (CS) (Tobacco Research and
    Health Institute, University of
    Kentucky) (organic extracts)
    Particle Size: 10 pi aliquots of
    organic extracts
    
    
    DEP extract (DP), gasoline
    engine exhaust particulate
    extract (GP), diesel exhaust
    SVOC extract (DSVOC),
    gasoline engine SVOC extract
    (GSVOC), NISTSRM1650a
    Particle Size: Gasoline PM:
    0.554 mg extract (mgPM)-1;
    Diesel PM: 0.363 mg extract
    (mg PM)-1
    
    Dose/Concentration: 2.5, 5, 10 pi; 0.30 -
    22.76 pg/m3
    Time to Analysis: Air samples collected,
    extracted. 90 min pre-incubation. 48 h
    incubation.
    
    Route: Cell Culture
    Dose/Concentration: 0.25, 2.5, 5, 12.5, 25
    m3/plate
    Time to Analysis: Standard Ames test
    protocol followed.
    
    
    Route: Cell Culture
    Dose/Concentration: 62.5, 12.5 pg TPM
    equivalent/plate
    Time to Analysis: Incubation, shaking 25
    min. Agar added. 48 h incubation. Rat lung
    explants incubated 18 h. 12 h incubation with
    treatments.
    
    Route: Cell Culture
    Dose/Concentration: 1.48, 4.44, 13.3, 40,
    120, 360, 1080 pg/plate
    Time to Analysis: 30 min preincubation. 48
    h (YG1029). 66 h (YG1024). Overnight
    preincubation 20 h.
    
    
    
    
    higher without S9 and increased with decreasing size.
    
    
    
    
    Extracts were mutagenic in all strains evaluated. No significant
    difference in response with or without metabolic activation. Activity
    in TA98NR suggests that the mutagenicity correlates with
    concentrations of air pollutants such as NOX.
    
    
    
    
    WS and CS were equally mutagenetic to TA98, but CS was 3-fold
    more mutagenetic to TA100 than WS. CS induced CYP1A1 in the
    explants, but WS did not.
    
    
    
    
    
    Mutations: All samples induced mutations in both strains. The
    increase was highly significant and dose-dependent. Response
    with S9 was generally greater than without S9. PM extract was
    more mutagenic than SVOC extract.
    DP, GP, and GSVOC: Dose-response was seen for DNA damage
    and micronuclei induction. GP, GSVOC and SRM 1650a were
    stronger inducers of micronuclei than DP.
    
    
    
    
    December 2009
                                                       D-164
    

    -------
      Reference
            Pollutant
                  Exposure
                            Effects
    Reference:
    Matsumoto et al.
    (2007, 1870201
    
    Species: S.
    typhimuriam
    
    Strain: TA98,
    TA100(±S9)
    ARM (airborne participate
    matter)
    
    APE (airborne participate
    extracts)
    
    (Hokkaido, Japan; residential)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: Crude APE: 979mg/m!
    air (CALUX BaP Equivalent (BaPEq)), 21
    mg/m3 air (CALUX TCDD Equivalent
    (TCDDEq)); Cleaned APE: 7.87 mg/m3 air
    (CALUX BaPEq), 0.614 mg/m3 air (CALUX
    TCDDEq)
    
    Time to Analysis: Air samples collected,
    extracted. Preincubation with S. typhimuriam.
    3, 24 h exposure in CALUX assay. RNA
    extracted from mice 6  days after last
    application.
    Most of the CALUX BaPEq for crude APE was derived from PAH-
    like compounds, as suggested by the CALUX BaPEq of cleaned
    APE accounting for 0.80% of CALUX BaPEq for crude APE.
    CALUX TCDDEq showed TCDD and similar compounds to have a
    low contribution. The TA100 strain was more mutagenic to APE,
    with and without S9. S9 increased mutagenicity in both strains.
    Reference:
    Pastorkova et al.
    (2004, 0874311
    Species: S.
    typhimuriam
    Strain: TA98,
    YG1041 (+S9)
    Reference:
    Rivedal et al.
    (2003, 0976841
    Species: S.
    typhimurim
    Strain: TA1 00,
    TA98,TA100NR,
    TA98NR,
    TA98/1.8-DNP6
    Reference:
    Seagrave et al.
    (2003, 0549791
    Species:
    Salmonella
    Strain: TA98,
    TA100
    PM (EOM) (Plzeh, Prague,
    Usti, Zd'ar - Czech Republic)
    Particle Size: 10pm
    (diameter)
    DEP(SRM1650)(organic
    extracts) (fractionated into
    PAH, nitro-PAH, dinitro-PAH,
    aliphatics, polar fraction)
    Particle Size: NR
    Compressed natural gas
    (CNG) emissions (heavy-duty
    vehicles): High emitter (HE),
    Normal emitter (NE), New
    technology (NT)
    Particle Size: NR
    Route: Cell Culture
    Dose/Concentration: TA98 (4 doses): 20-
    200 fjg/plate, YG1041 (4 doses): 4-20
    pg/piate
    Time to Analysis: Collected 24 h every 18th
    day, Oct-Mar, 1999-2003. Extracted. Ames
    assay. 70 h incubation.
    Route: Cell Culture
    Dose/Concentration: Ames: 300, 600
    DEP/plate; Gap junction: 100, 200 pg/mL
    DEP
    Time to Analysis: Extracted 16 h.
    Fractionated. Ames assay. Gap junction
    intracellular communication: exposed 1-6 h.
    Western blot.
    Route: Cell Culture
    Dose/Concentration: PM (mg/mi)- NE- 7.0,
    NT- 5.0, HE- 406; Recovered PM (mg/mi)-
    NE-1.26, NT- 0.71, HE- 57.1; Recovered
    SVOC- NE- 58, NT- 26.4, HE- 227.5
    Time to Analysis: Samples collected in
    filters 7x/day over several days. Recovered
    Significant dose-response effects in mutagenic potency of EOM
    occurred. Prague, one of the most polluted cities, had the highest
    mutagenicity values. Increasing time-trends were observed in the
    TA98 + S9 mutagenicity and PAH concentrations.
    TA100 was the most mutagenic without S9 activation. GJIC was
    dose- and time-dependently inhibited. The polar fraction was the
    most potent inhibitor. Nitro-PAH and dinitro-PAH were the most
    responsive fractions in the Ames assay.
    All three CNG emissions were mutagenic in both strains.
    Mutagenicity was reduced by S9 in TA100 but not in TA98. Activity
    ranking in both strains was HE>NE>NT
                                              PM, recovered SVOC extracts combined.
                                              Ames assay.
    Reference: PM (airborne, 4 sites: an oven
    Sharma et al. hall and receiving hall in a
    (2007, 1569751 waste incineration plant;
    heavy-traffic street;
    Species: S background; Mar-June 2005)
    typhimurium
    Particle Size: 2.5 urn
    Strain: TA98, Miampfprt
    YG1041, YG5161 (d'ameter)
    Cell Line:
    Human A549 lung
    epithelial cells
    Reference: Song PM (soluble organic fraction
    et al. (2007, (SOF) extracts from diesel
    1553061 engines using fuels blended
    with ethanol by volume: EO -
    Species: S. base diese| fue|; E5 . 5%- E10
    typhimurium . 10%; E15 - 15%; E20 - 20%)
    Strain: TA98, Particle Size: Density
    TA10° (g/cm3): EO- 0.8379; E5-
    Cell Line- Rat 0.8349; E1 0-0.8324; E1 5-
    fibroc?esL929 0.8301; E20- 0.8279
    cells
    Route: Cell Culture
    Dose/Concentration: 0.25 mg/ml
    Time to Analysis: Samples taken over 7-1 6
    days. A549 cells incubated 24 h. Comet and
    microsuspension assays performed.
    Route: Cell Culture
    Dose/Concentration: Ames Assay: 0.025,
    0.05, 0.1 mg/plate; Comet Assay: 0.125,
    0.25,0.5, 1.0mg/mL
    Time to Analysis: Samples extracted 24 h.
    Ames and comet assays performed
    DMA damage: Samples from all four sites induced DNA damage
    in the comet assay with the street samples more damaging than
    the oven hall sample.
    Mutations: Microsuspension assay was used to assess
    mutagenic activity. No mutagenic activity was observed for any of
    the non-polar fractions from any sample sites. The moderately
    polar fractions were all mutagenic, except for the oven hall
    sample, only when S9 was added. Comparatively, the polar and
    crude fractions were mutagenic without metabolic activation,
    suggesting a direct mutagenic effect.
    All PM extracts induced higher mutational response in TA98 (3- to
    5-fold increase over spontaneous) than in TA100 (2-to 3-fold
    increase). The highest brake specific revertants (BSR) ±S9 in both
    strains occurred with E20 and lowest BSR was in E5 (except in
    TA98 -S9). EO and E20 caused more significant DNA damage
    (similar in effect) than the other extracts. Damage was dose-
    dependent but variable with increasing ethanol volume.
    December 2009
                                                     D-165
    

    -------
      Reference
            Pollutant
                                          Exposure
                            Effects
    Reference:
    Zhang et al.
    (2007, 1571861
    
    Species: S.
    typhimurium
    
    Strain: TA98,
    TA100
    
    Cell Line: A549
    Gasoline engine exhaust
    (GEE)
    
    Methanol engine exhaust
    (MEE)
    
    Particle Size: NR
                           Route: Cell Culture
    
                           Dose/Concentration: MTT Assay- 0.05-0.8
                           GEE or MEE L/ml; MN Assay- 0.025, 0.05,
                           0.1, 0.2 GEE or MEE L/ml; Comet Assay-
                           0.025, 0.05, 0.1, 0.2, 0.4 GEE or MEE L/ml;
                           Ames Assay- GEE: 0.625, 1.25, 2.5, 5.0, 10,
                           20 L/plate; MEE: 0.3125, 0.625, 1.25, 2.5,
                           5.0,10, 20 L/plate
    
                           Time to Analysis: Organic extracts from
                           GEE and MEE. MTT assay- 24 h incubation,
                           followed by 2 or 24 h incubation, followed by
                           4 h incubation. MN assay- 24 h  incubation.
                           Comet assay. Ames assay- 72 h incubation.
    Mutagenicity: GEE was mutagenic in TA98 but not TA100, -S9 at
    10 and 20 L/plate and +S9 at >1.25 L/plate. Mutagenicity was
    higher with S9 than without at 0.625-10 L/plate and a dose-
    response was reported. MEE had no effect in either strain.
    
    MN: GEE significantly and dose-dependently induced MN. MEE
    had no significant effect at any dose.
    
    DMA damage: GEE significantly induced DNA damage at all
    doses compared to controls. MEE had no effect at any dose.
    Reference: Zhao
    et al. (2004,
    1009721
    
    Species: Rat
    
    Gender: Male
    
    Strain: SD
    DEP (SRM 2975)
    
    DEPE(SRM1975)
    
    Carbon black (CB) (Elftex-12
    furnace black, Cabot, Boston,
    MA)
    
    Particle Size: NR
                           Route: IT Instilled. Cell Culture.
    
                           Dose/Concentration: DEP orCB: 35mg/kg;
                           S9: 25, 50,100, 200 pg/plate; Cytosolic
                           protein: 20, 40, 80,160 pg/plate; Microsomal
                           protein: 5,10, 20, 40|jg/plate
    
                           Time to Analysis: Rats instilled. Sacrificed
                           1, 3, 7 days post-exposure. S9, cytosolic,
    DEP and CB-exposed lung S9 time-dependently decreased 2-
    aminoanthracene (2-AA) mutagenicity. Metyrapone and a-
    napthoflavone inhibited the S9-activation of 2-AA in DEP and CB
    exposed rats. Lung S9 increased the mutagenicity of DEPE but
    not of DEP or CB. Liver S9 reduced DEPE dose-dependently.
    CYP2B1 and CYP1A1 activated DEPE, with CYP2B1  being more
    effective.
    Age: NR
    Weight: -200 g
    Cell Line: S.
    typhimurium
    YG1024(±S9)
    Reference: Zhao
    et al. (2006,
    1009961
    Species: S.
    typhimuriam
    Strain: YGL024
    (±S9)
    
    DEP (SRM 2975)
    DEPE (SRM 1975)
    Aminoguanidine (AG)
    Particle Size: NR
    homogenates. Ames assay: 72 h incubation.
    Route: Cell Culture
    Dose/Concentration: NR
    Time to Analysis: Lung S9 obtained from
    rats used in in vivo experiment. Ames test.
    Modified microsuspension assay. All assays
    in duplicate plates. Repeated 3x.
    
    AG significantly lowered 2-aminoanthracene mutagenic activity of
    DEP or DEPE-exposed lung samples, with DEP being lowered the
    most.
    Table D-8.      Mutagenicity and genotoxicity data summary:  In vitro and in vivo.
        Reference
                     Particle
                                                     Exposure
                                  Effects
    Reference: Abou
    Chakra et al. (2007,
    0988191
    
    Species: Human
    
    Gender: Male,
    Female
    
    Age: 6-1 Syr and
    Adults
    
    Participant
    Characteristics:
    Non-smokers
    
    Cell Line: HeLa S3
    cells
    PM (3 French metropolitan cities: Urban  Route: Cell Culture
    PM25 and PM10 from "Residential
    Sector," "Proximity Sector," "Industrial
    Sector")
                                           Dose/Concentration: 200 pL organic
                                           extract; 20 pL aphidicoline
        (organic extracts)
    
        Particle Size: 2.5,10 pm (diameter)
                                           Time to Analysis: 24 h
               Seasonal variation was observed with genotoxic
               effects being greater in winter. PM25 was more
               active than PMio extracts. Samples from the
               "Proximity Sector" (downtown area with heavy traffic)
               exhibited the strongest genotoxic responses.
    Reference: Arrieta et  PM (El Paso, Texas; Juarez,
    al. (2003, 0962101
    
    Species: Rat
    
    Cell Line: Hepatoma
    (H4IIE)
    
    Species: Mouse
    
    Cell Line: Hepatoma
    H1l1.1c2
        Chihuahua, Mexico; Sunland Park, New
        Mexico) (organic extracts)
    
        Particle Size: 10 pm (diameter)
                                       Route: Cell Culture
    
                                       Dose/Concentration: EROD test: 0.03,
                                       0.17, 0.34, 0.50, 0.68, 4.96, 9.93 extract
                                       equivalents (m  air); Luciferase: 0.17, 0.51,
                                       1.26, 5.01 extract equivalents (m3 air)
    
                                       Time to Analysis: 24 h
               EROD activity declined at higher extract amounts,
               but luciferase activity was not inhibited. Cytotoxicity
               occurred only at extract equivalents to 0.47 m3 air.
               PAH concentration increased with PM mass.
    December  2009
                                                      D-166
    

    -------
        Reference
                  Particle
                  Exposure
                       Effects
    Reference: Bao et al.
    (2007, 0972581
    
    Cell Line: Human-
    hamster hybrid (AL)
    DEP (organic extracts) (SRM 2975)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 10, 20, 50,100 pg/mL
    
    Time to Analysis: Phagocytosis inhibitors:
    Exposed 24 h with or without cytochalasin B
    or ammonium chloride. Cytotoxicity: 24, 48 h
    incubation. Mutations: Exposed 24 h. 5-7
    days culture. Incubated additional 7-8 days.
    The nucleus of DEP-treated cells was condensed
    and shrunken compared to controls. DEPs
    accumulated in cells, disrupting the mitochondria!
    cristae, and were lodged in large cytoplasmic
    vacuoles. DEP  produced minimal toxicity CD59
    locus mutations dose-dependently increased but
    decreased when simultaneously treated with
    cytochalasin B or ammonium chloride.
    Reference: Carvalho-  PM (Sao Paulo, Brazil; spring, bus strike  Route: Cell Culture
    Oliveria et al. (2005,
    0778981
    
    Species: T. pallida; A.
    cepa
    and non-strike days) (organic extracts)
    
    Particle Size: 2.5 pm (diameter)
    Dose/Concentration: Strike day: 47.32
    pg/m ; Non-strike day: 43.01 pg/m
    
    Time to Analysis: 8 h. 24 h recovery. A.
    cepa roots induced 5 days. Exposed 30 h.
    Fixed 24 h.
    Element concentrations, sulfur and BTEX decreased
    on the strike day. Micronuclei decreased in T. pallida
    during the strike. Toxicity measured in A. cepa was
    not significant, but higher on strike days.
    Reference: Dybdahl
    et al. (2004, 0890131
    
    Species: Human
    
    Cell Line: A549
    DEP (SRM 1650)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 10, 50,100, 500 pg
    DEP/mL
    
    Time to Analysis: 2, 5, 24 h incubation.
    DEP induced dose-dependent increases of IL-1a, IL-
    6, IL-8, TNF-a. The cytokines increased 4-18-fold at
    the highest dose. Cell viability did not decrease.
    Comet tail length increased at 100 and 500 pg/mL
    for 2, 5, 24 h.
    Reference: Gabelova
    et al. (2007, 1564581
    
    Species: Human
    
    Cell Line: Hepatoma
    HepG2
    PM (PRG-SM, PRG-LB, Kosice, Sofia;    Route: Cell Culture
    winter, summer) (organic extracts)
                                         Dose/Concentration: 5-150 pg/mL
    Particle Size: 10pm (diameter)             *...„„„„„,
                                         Time to Analysis: 2, 24, 48 h
                                            Cell viability significantly decreased in the 24, 48 h
                                            exposure groups compared to the 2 h exposure
                                            group. DNA migration significantly dose-dependently
                                            increased at most concentrations. In general,
                                            oxidative DNA damage did not significantly increase.
    Reference: Gabelova
    et al. (2007, 1564571
    
    Species: Human
    
    Cell Line: Hepatoma
    Hep G2 cell line
    PM10 (Prague (Czech Republic), Ko'sice  Route: Cell Culture
    (Slovak Republic) and Sofia (Bulgaria);
    urban, winter, summer)                 Dose/Concentration: 5 -150 pg/ml
    (organic extracts)
    
    Particle Size: 10 pm (diameter)
    Time to Analysis: 24 h DNA adduct
    formation. 2 h Comet assay. Oxidative DNA
    damage measured by Fpg-sensitive sites.
    Total DNA adducts ranged from -60 to 200 adducts
    per 108 nucleotides. Extracts also produced
    approximately the same levels of strand breaks.
    Results suggested that the genotoxic potential of
    ambient air was at least 6-fold greater in the winter
    compared to summer.  No substantial difference was
    reported for oxidative DNA damage induced by
    summer vs. winter samples.
    Reference: Gong et
    al. (2007, 0911551
    
    Species: Human
    
    Cell Line:
    Microvascular
    endothelial (HMEC)
    DEP (aggregates, exhaust 4JB1-type     Route: Cell Culture
    LD.274 1,4-cylinder Isuzu diesel engine,
    10 torque load, cyclone impactor,
    dilution tunnel constant volume sampler)
    Dose/Concentration: 5,15, 25 pg/mL
    Particle Size: <1 pm (diameter)
    Time to Analysis: Cells treated with DEP,
    ox-PAPC (oxidized 1-palmitoyl-2-
    arachidonyl-sn-glycero-3-
    phosphorylchlorine), DEP+ox-PAPC
    HO-1 expression was dose-dependent and greatest
    with the DEP+ox-PAPC treatment. DEP significantly
    dose-dependently upregulated or downregulated a
    number of genes and was shown to have a
    synergistic effect with co-treatment of ox-PAPC. The
    most varying genes were significantly enriched for
    EpRE,  inflammatory response, UPR, immune
    response, cell adhesion, lipid metabolism, apoptosis
    and protein folding genes.
    Reference:
    Greenwell et al.
    (2003, 0974781
    
    Species: Rat
    
    Cell Line: Epithelial
    fluid; icosahedral
    bacteriophage
    cpX174-RFDNA
    PM (South Wales, UK) (urban,
    industrial)
    
    Particle Size: Coarse diameter: 10-2.5
    pm, Fine diameter: 2.5-0.1 pm
    Route: Cell Culture
    
    Dose/Concentration: Urban mean: 18.7 +
    4.7 mg/day; Industrial mean: 22.6 + 2.5
    mg/day
    
    Time to Analysis: 24 h air samples 4-11
    days. Substrates vortexed 1 h, suspended
    4 h, centrifuged 1  h. Oxidation assay.
    Industrial PM was more bioreactive than urban PM.
    Coarse fractions had greater oxidative potential and
    bioreactivity than fine fractions.
    Reference: Gu et al.
    (2005, 1959231
    
    Species: Hamster
    
    Strain: Chinese
    
    Cell Line: Lung
    fibroblast (V79)
    DPM (1980 model General Motors 5.7-L  Route: Cell Culture
    V-8 enaine)
                                         Dose/Concentration: 25, 50,100,150
    Particle Size: NR                     pg/mL; 10 pg DPM in 10 pg in DPPC/mL; 10
                                         pg DPM in 10 pg DMSO/mL
    
                                         Time to Analysis: Chromosomal aberration:
                                         24 h incubation. Treated 24 h. Incubated
                                         again 24 h. MN assay: 24 h treatment. Gene
                                         mutation: 24 h treatment. Cells replated. 7
                                         days expression times. Staining at 8,10
                                         days.
                                            DPM significantly and dose-dependently increased
                                            aberrant cells at 25-100 pg/mL DPM increased MN
                                            formation dose-dependently. Mutant frequencies
                                            were not significant and showed no dose-dependent
                                            trends. DPM was toxic to cells at the highest
                                            concentration.
    December 2009
                                                    D-167
    

    -------
        Reference
                  Particle
                  Exposure
                       Effects
    Reference: Gualtieri   TD (Tire debris, generated by rotating     Route: Cell Culture
    et al. (2005, 0978411   new vehicle wheel against a steel brush,
                         significant component of PM10) (organic   Dose/Concentration: 50, 60, 75 pg/mL
    Species: Human      extracts!
                         exlracls)                              Time to Analysis: Particles extracted 6 h.
    Cell Line: A549       Particle Si?e-1 n.an i im MiamptPrt       Cells subcultured every 3-4 days. After 24 h,
                                                              TD treatments 24, 48, 72 h.
    Particle Size: 10-80 pm (diameter)
                                            A time- and dose-dependent inhibitory effect on the
                                            reduction of MTT was seen. Mortality increased
                                            dose-dependently and was significantly greater than
                                            the controls. DMA strand breaks increased
                                            significantly in a dose-dependent manner. A
                                            significant cell cycle block in the G1 phase with a
                                            consequent decrease in the cell number in the S and
                                            G2/M phases was seen. Exposed cells had a
                                            modified morphology.
    Reference:
    Gutierrez-Castillo et
    al. (2006, 0890301
    
    Species: Human
    
    Cell Line: A549
    PM25 and PM10 (4 monitoring stations in  Route: Cell Culture
    Mexico City: (1) downtown high auto
    traffic, (2) two industrial areas with high
    levels of auto traffic and low vegetation,
    (3) medium-traffic residential area)
    (winter, spring , 4 sampling days in each
    period)
    
    (aqueous and organic extracts)
    
    Particle Size: 2.5 or 10 pm (diameter)
    Dose/Concentration: 0.05, 0.07, 0.1 m/r
    equivalents PM25; 0.82,1.25,1.63m3/ml
    equivalents PMi0
    
    Time to Analysis: 48 h
    Higher amounts of water-soluble metals were found
    in samples collected during winter. V\Mer-soluble
    extracts increased DMA damage 1.7-fold over the
    background. Similar results were observed with
    organic extracts. In general, PM25 extracts had
    greater genotoxic potential than PMi0 extracts, and
    water soluble fractions form both particle sizes were
    more genotoxic than the corresponding organic
    extracts.
    Reference: Izawa H
    et al. (2007, 1903871
    
    Cell Line: NA
    DEPE (4JB-1 Isuzu 4-cylinder direct-
    injection 2740ccdiesel engine; 1500
    rpm, 10 kg/m load)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: DEP: Ah-1
    experiment-111, 55.5, 27.8,13.9, 6.9, 3.5,
    1.7 pg/mL; Foods, polyphenols experiment-
    27.8 pg/mL
    
    Time to Analysis: DEPE incubated 2 h for
    dioxin toxicity measurement. Absorbance at
    405 nm measured. Food, polyphenol
    inhibitory effects: food extract or polyphenol
    solution added to cytosol solution, shaken 5
    min. DEPE added, shaken 5 min. 2 h
    incubation. Absorbance at 405 nm
    measured.
    The dioxin toxicity equivalent was 6,479 ± 58 ng
    DEQ/g of DEP. The absorbance showed a sigmoid
    curve and dose-dependently increased from 6.9 to
    27.8 pg DEP/mL The Ginkgo biloba extract
    significantly inhibited AhR activation significantly
    more than the other foods, and was followed by
    green tea, onions, and garlic. Quercetin and
    myricetin dose-dependently inhibited AhR activation.
    Ginkgolides A and B had weak inhibitory effects and
    resveratol was the weakest.
    Reference: Jacobsen  DEP (SRM 1650b)
    et al. (2008, 1565971
              	Carbon black (CB) (Printex 90)
    Species: Mouse       Partic|esize: DEP: 18.30 nm; CB: 14
    
    Cell Line: FE1-       nm; Agglomerates in suspensions: DEP
    MutaTM lung          Peaks- 249 nm, CB Peaks- 476 nm
    epithelial cells
                                         Route: Cell Culture
    
                                         Dose/Concentration: 37.5, 75 pg/mL
    
                                         Time to Analysis: 8 repeated 72 h
                                         incubations.
                                             Mutagenicity: The 75 pg/mL dose was significantly
                                             increased compared to the 37.5 jjg/mL dose. Linear
                                             regression showed a significant increasing trend by
                                             increasing exposure. There was no change in the
                                             total cell numbers.
    
                                             ROS: ROS production increased in DEP-treated
                                             cells after 3 h of exposure. CB-treated cells showed
                                             a dose-dependent increase.
    Reference: Karlsson   PM (urban dust particles, SRM 1649)     Route: Cell Culture
    et al. (2004, 1989761
    
    Species: Human
    
    Cell Line:
    Fibroblasts; calf
    thymusDNAwith
    human liver
    microsomes or rat
    liver S9
    (extracted with DCM, acetone, DMSO,
    water) (Fe 3% w/w, Ti 0.32% w/w, V
    0.04% w/w,  Mn 0.03% w/w, Cu 0.025%
    w/w)
    
    Particle Size: <10 pm (mean diameter)
    Dose/Concentration: 0.1,1.0,10,100
    pg/cm2
    
    Time to Analysis: Fibroblasts exposed
    24 h. Comet assay. Calf thymus incubated 2
    h with microsomes or S9. 32P-labelled.
    DMA damage increased dose-dependently, and a
    significant amount of DMA-damaged cells had
    particle interactions. DMA damage induced by the
    insoluble particle core significantly increased after
    each extraction. Native particles were more
    genotoxic than  those extracted with DMSO, DCM
    and water, but not with acetone or hexane. DMSO
    extracts had the most adduct-forming PACs, and
    water extracts had the most oxidizing substances.
    Reference: Karlsson   PM (subway station, urban street)
    et al. (2005, 0863921   Subway particles: 02, Fe (Fe from
                         Fe304) Street particles: Fe from Fe203
    Species: Human
                         Particle Size: 10 urn (diameter)
    Cell Line: A549
                                         Route: Cell Culture
    
                                         Dose/Concentration: Comet: 5,10, 20, 40
                                         pg/cm ; 8-oxodG: 10 pg/cm
    
                                         Time to Analysis: 4h.
                                             Both PM types induced concentration-dependent
                                             DMA damage, but subway particles were more
                                             potent. Subway particles caused more 8-oxodG
                                             formation and oxidation of dG, the latter of which
                                             was inhibited by deferoxaminemesylate. Oxidation
                                             from subway particles was due to nonsoluble, redox
                                             active substances, and soluble substances from
                                             street particles.
    Reference: Karlsson
    et al. (2006, 1566251
    
    Species: Human
    
    Cell Line: A549;
    monocytes from
    heparinized whole
    blood
    PM (wood- old, modern boiler; pellets-    Route: Cell Culture
    pellets burner, electrical ignition; tire-
    road simulator studded, friction tires;
    Street- busy street, Stockholm; Subway-
    platform near street)
    Dose/Concentration: 40 pg/cm2
    Particle Size: 2.5,10 pm (diameter)
    Time to Analysis: Cells grown 24 h. Comet
    assay. Monocytes incubated 10 days.
    Macrophages incubated 18 h.
    All particles tested caused DMA damage, but there
    was no significant difference between the size
    fractions. Subway particles were the most genotoxic.
    The urban street particles were the most potent
    inducers of the cytokines. On the Teflon filters, PMi0
    was somewhat more potent than PM2 5.
    December 2009
                                                    D-168
    

    -------
        Reference
                 Particle
                  Exposure
                                                               Effects
    Reference: Kubatova
    et al. (2004, 0879861
    
    Species: Monkey
    
    Cell Line: African
    green kidney COS-1
    (CV-1 cells with
    origin-defective SV40
    mutants) (+S9)
    PM (DE from diesel bus, wood smoke
    (WS) from chimney, hardwood smoke)
    (organic extracts)
    
    Particle Size: NR
    Route: Cell Culture                       WS had significantly increased cytotoxicity in
                                            fractions of 25-250°C, and DE in nonpolar fractions
                                            of 250 and 300°C and polar fractions of 50°C. The
                                            cytotoxicity of DE PM nonpolar fractions
                                            corresponded to increased concentrations of PAHs.
                 is- 24 h cvtotoxicitv 2 h SOS  WS was not 9enotoxic and DE was Qenotoxic in
                 .\s. M n cytotoxicity i n bus>  midpo|arjty fractjons (50-250°C). Genotoxic
                                            response was not increased after S9 activation.
    Dose/Concentration: 25, 50,100, 200
    pg/mL; 50mg of each material used for all
    experiments
    Reference: Landvik
    et al. (2007, 0967221
    
    Species: Mouse
    
    Cell Line: Hepatoma
    Nepal dc7  cells
    DEP extracts (DEPE in the paper)
    
    Particle Size: NR
    Route: Cell Culture
    
    Dose/Concentration: 10, 20, 30, 50, 70
    pg/mL
    
    Time to Analysis: 24 h
                                            50 and 70 pg/mL DEPE did not induce DMA
                                            fragmentation but did cleave caspase 3 to a minor
                                            extent.
    Reference: Mehta et
    al. (2008, 1904401
    
    Species: Human
    
    Cell Line: A549
    PM(SRM1949a)
    
    Particle Size: Ł 0.18 pm (diameter)
    Route: Cell Culture
    
    Dose/Concentration: 0, 50,100, 200, 400
    pg/mL
    
    Time to Analysis: Cell culture and cell
    viability assay: PM treatment 24 h.  10 days
    incubation. Host cell reactivation  assay:
    pGL3-luciferase plasmid UV irradiated 20
    min. PM treatment 24 h.  16 h transfection.
    24 h PM incubation. DMA repair synthesis
    assay: PM treatment 24 h. Proteinase K
    treatment 30 min. supf mutagenesis assay:
    PM treatment 24 h. PM culture 60 h. DMA
    extracted. Overnight incubation of
    transformed bacteria.
                                            PM reduced colony-forming ability and repair
                                            synthesis capacity was proportional to the PM
                                            concentration. PM dose-dependently decreased
                                            HCR capacity and decreased more than TSP. PM
                                            induced cyclobutane dimmers and pyrimidine<6-
                                            4>pyrimidones mutations in UV-irradiated supf.
    Reference: Meng
    and Zhang (2007,
    1989631
    Species: Rat
    Gender: Male
    Strain: Wistar Kyoto
    Age: NR
    Weight: Mean: 230g;
    Range: 200-250g
    Dell Line: AMs from
    reated rats
    Reference: Motta et
    al. (2004, 1989531
    Species: Hamster
    Strain: Chinese
    
    Cell Line: Epithelial
    iver, ovary
    Reference: Oh and
    Chung (2006,
    0882961
    Cell Line: A549
    Comet CHO-K1
    CBMN , H4IIE
    EROD-microbiassay)
    PM (Baotou, Wuwei, China) (normal
    weather, dust storms, Mar 1-31)
    (organic extracts, water soluble
    fractions)
    Particle Size: 2.5 |jm
    
    
    
    
    
    PM (Catania, Sicily; spring) (organic
    extracts)
    Particle Size: NR
    
    
    
    
    Crude extract (CE) DEP and fractions of
    CE of DEP (organic extracts: F1 -
    organic bases, F2 - organic acids, F3 -
    aliphatic, F4 - aromatic, F5 - slightly
    polar, F6 -moderately polar, F7 - high
    poisrj
    Particle Size: Diameter: <2.5 pm,
    87.71%, 2.5-10 fjm, 3.87%, >10 pm,
    n A^n/
    Route: Cell Culture
    Dose/Concentration: AM: 0, 33.3, 100, 300
    |jg/mL; Water-soluble: 0, 75, 150, 300
    pg/mL; Organic extracts: 0, 25, 50, 100
    pg/mL; Mass concentration normal day:
    68.49 + 28.83 pg/m3; Mass concentration
    dust storm day: 221.83 + 69.89 pg/m
    Time to Analysis: 24 h; cultures 4 h.
    
    
    
    
    Route: Cell Culture
    Dose/Concentration: 0.60, 1.21, 2.42, 4.85,
    9.70, 19.40 pg/mL; 0.78, 1.56, 2.12, 6.25,
    12.50, 25.00 pg/mL
    Time to Analysis: 24 h
    
    
    Route: Cell Culture
    Dose/Concentration: 100 |jg/mL
    Time to Analysis: DEP generated,
    extracted. Comet assay- 24 h incubation,
    CE, DEP exposed 24 h. MN assay- cultured
    24 h, 4 h treatment, growth medium
    incubation 20 h. EROD-microbioassay- 48 h.
    OC, NH4*, N03" were higher in normal weather
    PM25. S042", Ca2* were higher in dust storm PM25.
    Fe, Al, Ca, Mg were 5x higher in dust storm PM2s.
    Cell viability reduced in a concentration-dependent
    manner, with normal weather being slightly more
    cytotoxic. DNA damage was dose-dependently
    induced, with normal weather and organic extracts
    showing the greatest damage.
    
    
    
    
    
    The treatment was only slightly cytotoxic at the
    highest dose. DNA damage and aberrant cells
    generally increased with dose. No effect was seen in
    the Chinese hamster ovary cells without metabolic
    activation.
    
    
    
    DNA damage: CE significantly increased the
    amount of DNA damage in A549 cells with and
    without SKF-525A, a CYP450 inhibitor, and in CHO-
    K1 cells. It significantly increased MN formation ±S9
    com pared to controls.
    Organic Extracts: Organic base (F1) and neutral
    (F3-F7) fractions of CE of DEP significantly induced
    DNA damage without SKF-525A compared to
                                                                                                     controls. Adding SKF-525Acompletely inhibited
                                                                                                     damage caused by F3, F4, F6 and F7 but kept the
                                                                                                     effect of F1 similar to that without SKF and only
                                                                                                     partially inhibited that of F5. F2 did not induce DNA
                                                                                                     damage with or without SKF. All fractions except F6
                                                                                                     induced MN formation ±S9.
    December 2009
                                                   D-169
    

    -------
        Reference
                                      Particle
                  Exposure
                       Effects
    Reference: Poma et
    al. (2006, 0969031
                         PM (L'Aquila, Italy; urban); air samples
                         collected weekly basis Jan-Mar 2004.
    Species: Mouse       Carbon black (CB)
    
    Cell Line: RAW 264.7  Particle Size: 2.1-0.43 pm (diameter)
    Route: Cell Culture
    
    Dose/Concentration: 1,3,10 pg/cm2
    
    Time to Analysis: Cells cultured 48 h.
    Treatment 48 h. MN assay: 44 h incubation,
    28 h incubation.
    PM and CB dose-dependently reduced cell
    proliferation and induced micronuclei. PM and CB
    also reduced cellular metabolism of the
    macrophages and induced significant amounts of
    apoptosis. PM produced more micronuclei than
    equally-weighted CB.
    Reference: Roubicek  PM (Mexico City from an industrial area
    et al. (2007,1569291   with high-traffic and a medium-traffic
                         residential area)
    Species: Human
    
    Cell Line: A549       (aqUe°US °r °rganiC eXtraCtS)
                         Particle Size: 10 pm (diameter)
                                                             Route: Cell Culture
    
                                                             Dose/Concentration: 1.25,1.63, 2.5 mVml
                                                             equivalents of PMio
    
                                                             Time to Analysis: Cells treated 24 h
                                                             followed by 48 h incubation with
                                                             cytochalasin B. Micronuclei frequency
                                                             determined.
                                            Water and organic extracts induced a significant
                                            dose-dependent increase in the micronuclei
                                            frequency. After doses of PM from different regions
                                            were normalized for mass differences, the genotoxic
                                            potency was higher for samples from the industrial
                                            area.
    Reference: Salonen
    et al. (2004, 1870531
                         PM (Vallila, Finland; busy traffic site;
                         spring, winter)
    Species: Mouse       Particle Size: <10 pm (diameter)
    
    Cell Line: RAW264.7
    Route: Cell Culture
    
    Dose/Concentration: 15, 50,150, 500,
    1000|jg/mLofRPMI
    
    Time to Analysis: 24 h
    PAHs decreased from winter to spring. TNF-a dose-
    dependently increased and was higher in spring
    samples. IL-6 generally increased in spring but not in
    winter. NO dose-dependently increased and was
    higher in winter. Cell viability generally decreased
    but there were no consistent potency differences
    between the samples. Generally, proinflammatory
    activity, cytotoxicity and IL-6 were associated with
    the insoluble PM fractions. Polymyxin B inhibited IL-
    6 and TNF-a. 'OH and 8-hydroxy-2'-deoxyguanosine
    dose-dependently increased and were higher in the
    spring and winter, respectively.
    Reference: Seaton et  PM (3 busy London underground (LU)
    al. (2005,1989041     stations and cabs) (LU dust in PM2 5
                         samples: iron oxide 64-71%, chromium
                         0.1-0.2%, manganese 0.5-1%, copper
                         <0.1-0.9%; respirable dust samples: 1-
                         2%)
    
                         Particle Size: Diameter: <2.5 pm, 10
                         pm,  Median diameter: 0.4 pm
    Species: Human
    
    Cell Line: A549
    Route: Cell Culture
    
    Dose/Concentration: Assays: 1,10, 50,
    100|jg/mL
    
    Time to Analysis: 8, 24 h.
    PM10 caused less LDH release, IL-8 stimulation and
    free radical activity than LU dust particles that
    contained PM25. Chelation had little effect on PMio
    soluble components.
    Reference:           PMio (Prague, Czech Republic; Ko'sice;
    Sevastyanova et al.    Slovak Republic; Sofia, Bulgaria)
    (2007,1569691        (urban, summer, winter)
    
    Species: Human       (organic extracts)
    
    Cell Line: HepG2 cell  Particle Size: 10 pm (diameter)
    line, embryonic lung
    diploid fibroblasts
    (HEL), or acute
    monocytic leukemia
    cells (THP-1)
                                                             Route: Cell Culture
    
                                                             Dose/Concentration: 10-100 pg/ml
    
                                                             Time to Analysis: 24 h
                                            DNA adducts were observed in all cell types
                                            evaluated. Highest adduct levels were observed in
                                            HepG2 cells, followed by HEL and THP-1 cells. A
                                            correlation between DNA adduct levels and
                                            carcinogenic PAH content was observed in HepG2
                                            cells at 50 pg/ml.
    Reference: Shi et al.
    (2003, 0882481
    
    Species: Human
    
    Cell Line: A549
                         PM (Dusseldorf, Germany, July-Dec.)
                         Weekly samplings July-Dec 1999.
    
                         Particle Size: Fine diameter: <2.5 pm;
                         Coarse diameter: 10-2.5 pm
    Route: Cell Culture
    
    Dose/Concentration: Fine: 0.57-2.49 mg;
    Coarse: 0.66-1.89 mg; Concentration: 0.57
    mg/mL
    
    Time to Analysis: NR
    Coarse and fine particles generated 'OH, but coarse
    particles had significantly higher 'OH formation as
    well as 8-hydroxy-2'-deoxyguanosine formation. 8-
    hydroxy-2'-deoxyguanosine and 'OH had a
    significant correlation.
    Reference: Skarek et
    al. (2007, 0968141
    
    Species: Rat
    
    Cell Line: Modified
    hepatomaH4IIE.Iuc;
    SOS: E. coli PQ37
    (±S9)
                         PM (urban: Usti and Laben, Karvina;
                         background: Cervenohorske sedlo,
                         Kosetice - Czech Republic; July)
                         (organic extracts, TSP); GP (gas
                         phase). 24 h samples July 2002
    
                         Particle Size: <2.5 pm (diameter)
    Route: Cell Culture
    
    Dose/Concentration: SOS: 8, 4, 2,1 m3/ml;
    Dioxin:TSP+GP-8,1.33, 0.22, 0.04m3/ml,
    PM25+GP:4, 0.66, 0.11, 0.02m3 ml-1
    
    Time to Analysis:. SOS chromotest: 22 h
    incubation. Dioxin toxicity test: 24 h
    exposure.
    The urban areas had a much greater level of
    carcinogenic PAHs and overall number of PAHs than
    the background areas. Significant genotoxic activity
    was only detected at TSP+GP without S9 from urban
    areas. PM2 5+GP had lower dioxin activity at the
    urban areas, but similar levels of toxicity were seen
    for both treatments in the background areas.
    Reference: Song et
    al. (2007, 1553061
    
    Species: S.
    typhimurium
    
    Strain: TA98, TA100
    
    Cell Line: Rat
    fibrocytes L-929 cells
                         PM (soluble organic fraction (SOF)
                         extracts from diesel engines using fuels
                         blended with ethanol by volume: EO -
                         base diesel fuel; E5 - 5%; E10 -10%;
                         E15-15%;E20-20%)
    
                         Particle Size: Density (g/cm3): EO-
                         0.8379; E5-0.8349; E10-0.8324; E15-
                         0.8301 ;E20-0.8279
    Route: Cell Culture
    
    Dose/Concentration: Ames Assay: 0.025,
    0.05, 0.1 mg/plate; Comet Assay: 0.125,
    0.25,0.5,1.0 mg/mL
    
    Time to Analysis: 24 h
    All PM extracts induced higher mutational response
    in TA98 (3- to 5-fold increase over spontaneous)
    than in TA100 (2-to 3-fold increase). The highest
    brake specific revertants (BSR) ±S9 in both strains
    occurred with E20 and lowest BSR was in E5
    (except in TA98 -S9). EO and E20 caused more
    significant DNA damage (similar in effect) than the
    other extracts. Damage was dose-dependent but
    variable with increasing ethanol volume.
    December 2009
                                                                         D-170
    

    -------
        Reference
    Particle
    Exposure
    Effects
    Reference: Ueng et   MEP (Yamaha cabin motorcycle 2-strok  Route: Cell Culture
    al. (2005, 0970541     50-cc engine)
    Species: Human      Particle Size: NR
    
    Cell Line: Lung
    epithelium CL5
    (cancerous), BEAS-
    2B, WI-38 normal
    lung fibroblast
                          Dose/Concentration: 1,10,100, 200 pg/mL
    
                          Time to Analysis: microarray analysis. RT-
                          PCR: 2 h.ELISA: 12 h incubation.
                          Centrifuged 24 h post-treatment. Bioactivity:
                          12 h incubation. Centrifuged 24 h post-
                          treatment. Medium replaced 48 h post-
                          incubation. Fibroblasts determined 96 h
                          post-incubation. Time response studies: 3-
                          48 h treatment. Concentration response
                          studies: 6 h treatment.
                             Drug Metabolism Array Study: MEP increased
                             CYP1A1,CYP3A7andUGT2B.
    
                             Cytokine Array Study: MEP increased fibroblast
                             growth factor (FGF)-6,  FGF-9, IL-1a,  IL-22 and
                             vascular endothelial growth factor (VEGF)-D mRNA.
    
                             Oncogene, Tumor Suppressor, Estrogen
                             Signaling Pathway: MEP increased  fra-1, c-src,
                             SHC, p21, COX7RP, and decreased p53 and Rb
                             expression.
    
                             RT-PCR: MEP increased CYP1A1, CYP1B1, IL-6,
                             IL-11,  IL-1a, FGF-6, FGF-9, VEGF-D, fra-1 and p21.
    
                             Concentration and Time  Responses:
                             Concentration and time-dependent increases
                             occurred for FGF-9, IL-1a, IL-6, IL-11, but decreased
                             time-dependently after 6 h exposure.
    
                             BEAS-2B Cells: MEP  had concentration-dependent
                             increases on CYP1A1  and CYP1B1 but did not
                             affect anything else.
    
                             Peroxide, MEP+NAC, WI-38 Cells: MEP increased
                             peroxide production. The MEP+NAC treatment
                             reduced MEP-elevated levels of IL-1a, IL-6, FGF-9,
                             VEGF-D to control levels. Fibroblasts increased in
                             WI-38 cells.
    Reference:
    Umbuzeiro et al.
    (2008, 1904911
    Species: Salmonella
    typhimurium
    Strain: TA98,
    YG1041 (+/-S9)
    Reference:
    Upadhyay et al.
    (2003, 0973701
    Species: Human
    Cell Line A549
    Reference:
    Valavanidis et al.
    (2005, 0964321
    Cell Line: NR
    Reference: Xu and
    Zhang (2004,
    0972311
    Species: Human
    Cell Line: A549
    PM (urban; Sao Paulo, Brazil- Cerqueira
    Cesar street station, Ibirapuera park
    station) (winter- June 17, 18; average
    temperature: 16°C) (EOM)
    Particle Size: NR
    PM (Dusseldorf, Germany) (Particles
    contain carbon (19.70%),
    hydrogen(1.4%),nitrogen (<05%),
    oxygen(14.12%), sulfur (2.09%), ash
    (63.24%)) (lonizable metals
    concentrations (ppm): Co(103),
    Cu(48),Cr(104),Fe(14,521 , Mn(21.3),
    Ni(1,519),Ti(131),V(2,767
    Particle Size: NR
    PM (TSP: high volume pumps, Athens;
    DEP: 2.0L engine GM Astra; GEP: 1.6L
    passenger vehicle Ford; Wood smoke
    soot: domestic fireplace exhaust
    chimney; PMi0: high volume sampling
    system, Athens; PW2S\ high volume
    cascade impactor (Anderson) system
    Particle Size: >10.2-<0.41 pm
    (diameter)
    PM (Taiyuan, Beijing; Nov-Feb)
    (Taiyuan: coal-fume pollution; Beijing:
    coal-fume and vehicle exhaust)
    Particle Size: 2.5 pm (diameter)
    Route: Cell Culture
    Dose/Concentration: Cerqueira Cesar:
    UPM- 156 pg/m3, EOM- 57.7 mg/total UPM;
    Ibirapuera Park: UPM- 32 pg/mr EOM- 41.7
    mg/total UPM; Salmonella assay- 0.5, 1, 5,
    10,50, 100UPMequiv/plate(|jg)
    Time to Analysis: Organic extraction 20 h.
    PAH fractionation.
    Route: Cell Culture
    Dose/Concentration: 1, 5, 25, 100 pg/cm2;
    10,25,50, 100|jg/cm2
    Time to Analysis: 1, 4, 8, 12, 24 h.
    Route: Incubation
    Dose/Concentration: 20, 40 mg/5mL
    Time to Analysis: PM incubated with H202
    and 2'-deoxyguanosine (dG). Stored 3-7
    days at -20°C.
    Route: Cell Culture
    Dose/Concentration: 5, 50, 200 pg/mL
    Time to Analysis: 12-24h
    The TSP and EOM were similar for both sites. The
    PAH fraction had very low mutagenicity for the
    Cerqueira Cesar sample in the YG1041 strain and
    no mutagenicity for the Ibirapuera sample. Nitro-PAH
    and oxy-PAH had similar mutagenetic activities from
    both samples. S9 decreased mutagenicity in nitro-
    PAH but was increased in oxy-PAH. DNA adduct
    levels were dose-dependent and not different
    between the two sites.
    PM induced dose- and time-dependent reductions in
    ds-DNA due to the formation of DNA-SB. The
    soluble component caused higher DNA damage.
    Apoptosis and DNA fragmentation increased dose-
    dependently AYm decreased dose-dependently in
    control cells, but not in cells with Bcl-xl
    overexpression. PM caused activation of caspase 9.
    Pretreatment with iron chelators or a free radical
    scavenger reduced PM-induced DNA-SB formation,
    DNA fragmentation, caspase 9 activation, and
    weakened AYm reductions.
    PM generated 'OH by a Fenton reaction, which is
    increased by the addition of EDTA but inhibited by
    deferoxamine. PM dose-dependently induced dG
    hydroxylation and 8-hydroxy-2'-deoxyguanosine
    formation. Transition metals Ni, V, Co, Crthat are
    capable of redox cycling electron producing ROS
    were found in the PM samples.
    Taiyuan had a significantly higher daily PM25
    average than Beijing. It was shown that the smaller
    the particulate diameter, the higher the concentration
    of BaP and Pb. A dose- and time-response
    relationship was seen in DNA fragmentation.
    December  2009
                                     D-171
    

    -------
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    Yokota S; Furuya M; Seki T; Marumo H; Ohara N; Kato A. (2004). Delayed exacerbation of acute myocardial
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    Yokota S; Mizuo K; Moriya N; Oshio S; Sugawara I; Takeda K. (2009). Effect of prenatal exposure to diesel exhaust on
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    December 2009                                       D-197
    

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      Annex F. Source Apportionment  Studies
    Table F-1.     Epidemiologic studies of ambient PM sources, factors, or constituents
    Reference: Andersen et Subjects: NR N: NR
    al. (2007.093201)
    Exposure: NR
    Location: 1 monitor in
    Copenhagen, Denmark/
    6yr, but apportionment
    done for 1 .5 yr only
    (2002-2003)
    
    Particle Size: PM10
    Number of
    Constituents
    considered for
    grouping: 31
    
    
    
    
    Grouping
    method :PCA +
    PMF/CMB hybrid
    (COPREM)
    # of groups: 12,
    but only 6 used in
    relating to health
    effects, and CO,
    N02
    Groups/Factors/ Sources:
    Road, vehicle, salt,
    biomass, oil, coal, rock,
    lime, NaN03, NH4N03,
    (NH4)2S03, (NH4S04)
    
    
    
    
    PM variables used:
    Mass contribution of
    sources
    
    
    
    
                         Results: Single pollutant models: Biomass, secondary compounds, oil, and crustal significantly associated with CVD HA
                         (4-day ma). Biomass and secondary components significantly associated with respiratory HA (5-day ma). No significant effects
                         for asthma HA in children (6-day ma).
    
                         Two pollutant models: Crustal effect for CVD admissions remained robust. Biomass effect for respiratory admissions was
                         highest. Effect of vehicle source remained robust for asthma admissions in children in presence of other PM 10 sources.
    Reference: Bell et al. (Bell
    etal., 2009, 191007)
    Location: PM25:
    2000-2005 (6 yr)/1 06 US
    counties/EPA composition
    data
    Subjects: NR N: NR
    Exposure: NR
    Number of
    Constituents
    considered for
    grouping: 16
    elements + N03,
    S04, EC, OC
    Grouping
    method: NR
    # of groups: NR
    Groups/Factors/ Sources:
    NR
    PM variables used:
    Every component (16
    elements + N03,
    S04,EC, OC)
    PM10:1987-2000/100
    counties/EPA composition
    data
    
    Particle Size: PM10, PM2.5
    Results: Mortality: Ni significantly increased PM10 mortality risks. However, effect of Ni was not significant when New York City
    was removed, in a sensitivity analysis conducted by selectively removing cities from the overall estimate.
    
    Hospital Admissions: CVD and respiratory HAs higher in counties with higher EC, Ni, and V PM25. In CVD association
    between PM25, RR and V robust to inclusion of EC or V, and V robust to inclusion of EC.
    Reference: Cakmak et al.
    (2009,191995)
    Location: 1 monitor in
    Santiago, Chile
    Particle Size: PM25
    Subjects: NR N: NR
    
    Exposure:
    1998-2009
    (8.3 yr)
    
    Number of
    Constituents
    considered for
    grouping: 16
    elements + CO,
    N02, S02, EC,
    OC
    Grouping
    method: PCA
    # of groups: 4
    
    Groups/Factors/ Sources:
    Vehicle (CO, N02, EC, OC),
    Soil (Al, Ca, Fe, Si),
    Combustion (Cr, Cu, Fe,
    Mn.Zn), Factor 4 (Br.CI,
    Pb)
    PM variables used:
    individual components,
    then groupings
    
                         Results: Individual components: EC, OConly stat. sign, risk estimates for total, cardiac, and respiratory mortality for 1-day lag
                         after adjustment for other elements.
    
                         Groupings: Lag 1. Vehicle factor: Increased total mortality, cardiac mortality, and respiratory mortality. Soil factor: increased
                         cardiac mortality and respiratory mortality (but smaller than vehicle factor RRs). Combustion factor: greatest RR for respiratory
                         mortality, but significant for total and cardiac mortality. Factor 4: increased total, cardiac, and respiratory mortality. Point
                         estimates for Factor 1 significantly different from Factors 3 and 4. Elderly had higher risk estimates for combustion and soil
                         sources. No significant effect modification by gender or season.
    Reference: Franklin et al.
    (2008, 155779)
    Location : STN/25
    communities/2000-2005
    (6yr)
    Particle Size: PM25
    Subjects: NR N: NR Number of
    Constituents
    Exposure: NR considered for
    grouping: 15
    elements + EC,
    OC, N03
    Grouping Groups/Factors/Sources: PM variables used:
    method: NR NR Every component
    # of groups: NR
    Results: The PM25-mortality association was significantly modified by Al, As, Sulfate, Ni, and Si. When including a combination
    of species proportions and using backwards elimination Al, sulfate, and Ni remained significant. Aland Ni explained most of the
    residual heterogeneity.
     Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
     Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
     developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
    December 2009
                                      F-1
    

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                Annex  E.  Epidemiologic  Studies
    E.1. Short-Term  Exposure and Cardiovascular Outcomes
    
    E.1.1.Cardiovascular Morbidity Studies
    Table E-1    Short-term exposure - cardiovascular morbidity outcomes:
              Study
         Design & Methods
          Concentrations
      Effect Estimates (95% Cl)
    Reference: Baccarelli et al. (2007,
    0913101
    Period of Study: Jan 1995-Aug 2005
    
    Location: Lombardia region, Italy
    Outcome: Fasting and postmethionine-
    load total homocysteine (tHcy)
    
    Age Groups: 11-84yr
    
    Study Design: Cross-sectional / Panel
    
    N: 1,213 participants
    
    Statistical Analyses: Generalized
    additive models
    
    Covariates: Age, sex, BMI, smoking,
    alcohol, hormone use, temperature, day
    of the yr, and long-term trends
    
    Season: Adjusted for long-term trends
    to account for season
    
    Dose-response Investigated? No
    
    Statistical Package: R v2 2 1
    
    Lags Considered: 1-day, 7-day ma.
    Pollutant: PMio (some TSP measures
    used to predict PM10)
    
    Averaging Time: 24 h
    
    Mean (SD): NR
    
    Percentiles:
    25th: 20.1
    50th: 34.1
    75th: 52.6
    
    Max: 390.0
    
    Monitoring Stations: 53
    
    Copollutant: CO, N02, S02, 03
    PM Increment: IQR
    
    Percent Change: [Lower Cl, Upper
    Cl]: Homocysteine, fasting: 0.4 (-2.4,
    3.3)
    Homocysteine, postmethionine-load:
    1.1 (-1.5,3.7)
    
    Percent Change: per 26.7m3
    increase in 7-day ma of PMio
    
    Homocysteine, fasting: 1.0 (-1.9, 3.9)
    Homocysteine, postmethionine-load:
    2.0 (-0.6, 4.7)
    
    Percent Change: on fasting
    homocysteine per IQR increase in
    24-h PMio levels
    
    Among smokers: 6.2 (0.0,12.7)
    Among non-smokers: -1.6 (-5.5, 2.5)
    
    Percent Change: on postmethionine-
    load homocysteine per IQR increase
    in 24-h PMio levels: Among smokers:
    6.0(0.5,11.8)
    
    Among non-smokers: -0.1 (-3.6, 3.5)
    December 2009
                           E-1
    

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                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Baccarelli et al. (2007,
    0907331
    
    Period of Study: Jan 1995-Aug 2005
    
    Location: Lombardia region, Italy
    Outcome: Prothrombin time (PT)
    
    Activated partial thromboplastin time
    (APTT)
    
    Fibrinogen
    Functional antithrombin
    Functional protein C
    Protein C, antigen
    Functional protein S
    
    Free protein S
    
    Age Groups: 11-84yr
    
    Study Design: Cross-sectional / Panel
    
    N: 1,218 participants
    
    Statistical Analyses: Generalized
    additive models
    
    Covariates: Age, sex, BMI, smoking,
    alcohol, hormone use, temperature, day
    of the yr, and long-term trends
    
    Season: Adjusted for long-term trends
    to account for season
    
    Dose-response Investigated? No
    
    Statistical Package:  R software v2.2.1
    Pollutant: PMi0 (some TSP measures
    used to predict PMio)
    
    Averaging Time: Hourly concentrations
    used to calculate lags of same day, 7-
    day, 30-day, and h 0-6
    
    Mean (SD): NR
    
    Percentiles:
    Sep-Nov:
    5th: 33.1
    50th: 51.2
    75th: 76.5
    Max: 148.9
    
    Dec-Feb:
    25th: 47.9
    50th: 68.5
    75th: 95.3
    Max: 238.3
    
    Mar-May:
    25th: 30.0
    50th: 64.1
    75th: 64.8
    Max: 158.5
    
    Jun-Aug:
    25th: 28.0
    50th: 44.3
    75th: 61.3
    Max: 94.7
    
    Monitoring Stations: 53 sites
    
    Copollutant: CO, N02, S02,  03
    PM Increment: SD
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Estimated changes in endpoint
    
    PT (international normalized ratio):
    At time of blood sample: -0.06 (-0.12,
    0.00)
    Avg levels 7 days prior: -0.03  (-0.10,
    0.04)
    Avg levels 30 days prior: -0.08 (-0.14, -
    0.01)
    (Hourly ma  presented in Fig 2)
    
    APTT (ratio to reference plasma):
    At time of blood sample: 0.02  (-0.04,
    0.08)
    Avg levels 7 days prior: 0.00 (-0.07,
    0.06)
    Avg levels 30 days prior: 0.01  (-0.06,
    0.08)
    
    Fibrinogen:
    At time of blood sample: 0.01  (-0.05,
    0.07)
    Avg levels 7 days prior: -0.03  (-0.09,
    0.04)
    Avg levels 30 days prior: -0.02 (-0.09,
    0.05)
    
    Functional antithrombin:
    At time of blood sample: -0.02 (-0.09,
    0.04)
    Avg levels 7 days prior: -0.06  (-0.13,
    0.01)
    Avg levels 30 days prior: -0.06 (-0.13,
    0.02)
    
    Functional protein C:
    At time of blood sample: 0.00  (-0.06,
    6.1)
    Avg levels 7 days prior: -0.06  (-0.12,
    0.01)
    Avg levels 30 days prior: -0.06 (-0.14,
    0.01)
    
    Protein C, antigen:
    At time of blood sample: 0.00  (-0.06,
    6.0)
    Avg levels 7 days prior: -0.04  (-0.10,
    0.03)
    Avg levels 30 days prior: -0.06 (-0.14,
    0.01)
    
    Functional protein S:
    At time of blood sample: 0.04  (-0.03,
    0.10)
    Avg levels 7 days prior: -0.03  (-0.11,
    0.06)
    Avg levels 30 days prior: -0.14 (-0.23,
    -0.05)
    
    Free protein S:
    At time of blood sample: 0.05  (-0.01,
    0.10)
    Avg levels 7 days prior: 0.01 (-0.05,
    0.07)
    Avg levels 30 days prior: -0.01 (-0.08,
    0.06)
    December 2009
                                      E-2
    

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                  Study
           Design & Methods
            Concentrations1
            Effect Estimates (95% Cl)
    Reference: Barclay et al.
    (2009, 1799351
    
    Period of Study: Jan 2003-May 2005
    
    Location: Aberdeen, Scotland
    Outcome: Haematological outcomes,
    Heart Rhythm outcomes, & Heart Rate
    Variability outcomes
    
    Age Groups: 70.4 (8.9)
    
    Study Design: Panel
    
    N: 132 patients w/ chronic heart failure
    
    Statistical Analyses: Linear & Mixed
    Effects Regression Model
    
    Covariates: Age, temperature,
    humidity, pressure
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: Lags 0-2 day
    Pollutant: PM,0
    
    Averaging Time: daily
    
    Mean (SD): 20.25
    
    Min:7.375
    
    Max: 68.3
    
    Monitoring Stations: 1
    
    Copollutant: PM25, PNC, N02
    
    Co-pollutant Correlation:
    N02 city: 0.294
    NO city: 0.112
    N02 personal: 0.055
    PNC DEOM: 0.241
    PM25 total: 0.476*
    PM25 traffic: 0.882*
    PNC total: 0.125
    PNC traffic: 0.190
    
    'Correlations based on 3-day avg
    concentrations
        PM Increment: NR
    
        Beta (Lower Cl, Upper Cl):
    
        Haemoglobin: 0.136 (-0.274, 0.546)
        Mean corpuscular haemoglobin: 0.030
        (-0.232, 0.291)
        Platelets: 0.096 (-0.923,1.115)
        Haematocrit:0.131  (-0.289,0.551)
        White blood cells: 0.034 (-1.175,1.244)
        C reactive protein: -4.872 (-12.094,
        2.351)
        IL-6: 2.207 (-4.995,  9.410)
        von Willebrand factor: 0.660 (-2.651,
        3.970)
        E-selectin:-0.536 (-2.528, 1.457)
        Fibrinogen:-0.432 (-2.470,1.607)
        Factor VII: 0.990 (-1.265, 3.245)
        day-dimer:-1.225 (-4.505, 2.055)
        All arrhythmias: -3.447 (-11.521, 4.627)
        Ventricular ectopic beats: -2.110 (-
        12.135,7.915)
        Ventricular couplets: -1.561  (-10.811,
        7.689)
        Ventricular runs: -0.709 (-6.677, 5.259)
        Supraventricular ectopic beats: 0.033
        (-9.242, 9.308)
        Supraventricular couplets: 0.006
        (-8.618, 8.629)
        Supraventricular runs: 3.710 (-2.847,
        10.266)
        Avg HR: 0.321 (-0.197, 0.838)
        24 hSDNN: 1.040 (-0.415, 2.494)
        24 hSDANN: 1.195 (-0.473, 2.863)
        24 hRMSSD: 0.321 (-0.197, 0.838)
        24 hPNN: 2.837 (-3.791, 9.465)
        24 h LF power: 0583 (-3.622, 4.787)
        24 hLF normalized:-3.137 (-5.540,
        -0.733)*
        24 h HF power: 0.872 (-4.649, 6.392)
        24 h HF normalized: -2.223 (-4.952,
        0.505)
        24 h LF/HF ratio: -0.296 (-3.832, 3.240)
        *p < 0.05
    
        Notes: LF= low frequency
        HF= high frequency
    Reference: Briet et al. (2007, 0930491
    
    Period of Study: NR
    
    Location: Paris, France
    Outcome: Endothelial Function
    
    Age Groups: 20-40 yr
    
    Study Design: Panel
    
    N: 40 white male nonsmokers
    
    Statistical Analyses: Multiple Robust
    Regrssion
    
    Covariates: R53R/R53H genotype,
    diet, subject factor, visit, temperature
    
    Dose-response Investigated? No
    
    Statistical Package: NCSS
    
    Lags Considered: 0-5 day
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    5 day Mean (SD): 43 (10)
    
    Monitoring Stations: NR
    
    Co-pollutant: PM25, S02, NO, NO;
    
    Co-pollutant Correlation: N/A
        PM Increment: 1 SD
    
        Beta (Lower Cl, Upper Cl), P, R2:
        Flow-mediated brachial artery dilation:
        0.07 (-0.62, 0.76), NS, 0.03
    
        Reactive hyperemia:
    CQ 15.91 (7.74, 24.0), O.001, 0.16
    December 2009
                                      E-3
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Choi et al. (2007, 0931961
    
    Period of Study: 2001-2003
    
    Location: Incheon, South Korea
    Outcome: Blood pressure              Pollutant: PMi0
    
    Study Design: Cross-sectional          Averaging Time: Measured hourly and
                                         calculated 24-h means
    N: 10459 subjects with a hospital health
    examination                          Percentiles:
                                         Warm season: Median: 36.7
    Statistical Analyses: Linear regression  Co|d season: Median: 45 7
                                        Covariates: Season: Effect
                                        modification by season
                                         Monitoring Stations: 9 stations
    
                                         Copollutant: N02, S02
                                         PM Increment: 10 pg/m
    
                                         Effect Estimate [Lower Cl, Upper Cl]:
                                         Estimate (p-value) for the relationship
                                         between systolic blood pressure (SBP)
                                         and diastolic blood pressure (DBP) and
                                         an increase in PMi0 on lag day 1
    
                                         SBP: Warm season: 0.0798 (p < 0.001)
    
                                         DBP: Warm season: 0.0240 (p < 0.001)
    
                                         Note: No evidence of associations
                                         between PMi0 and BP during the cold
                                         season
    Reference: Chuang et al. (2007,
    0910631
    
    Period of Study:
    Between Apr-Jun 2004 or 2005
    
    Location: Taipei, Taiwan
    Outcome: High-sensitivity C-reactive
    protein (hs-CRP)
    
    Fibrinogen, plasminogen activator
    fibrinogen inhibitor-1  (PAI-1), tissue-
    type plasminogen activator (tPA), 8-
    hydroxy-2'-deoxyguanosine(8-OHdG),
    and log-transformed  HRV indices
    (SDNN = standard deviation of NN
    intervals, r-MSSD = square root of the
    mean of the sum of the squares of
    differences between  adjacent NN
    intervals, LF = low frequency [0.04-
    0.15Hz], and HF= high frequency
    [0.15-0.40HZ])
    
    Age Groups: 18-25yr
    
    Study Design: Panel (cross-sectional)
    
    N: 76 students
    
    Statistical Analyses: Linear mixed-
    effects models
    
    Covariates: Age, sex, BMI, weekday,
    temperature of previous day, relative
    humidity
    
    Season: Only 1  season of data
    collection
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Pollutant: PM,0
    
    Averaging Time: Hourly data used to
    calculate avg over 1- to 3-day periods
    
    Mean (SD): 1-day avg: 49.2 (18.0)
    2-day avg: 55.3 (18.6)
    3-day avg: 54.9 (18.2)
    
    Range (Min, Max):
    1-day avg: 29.5, 83.4
    2-day avg: 25.5, 85.1
    3-day avg: 22.2, 87.2
    
    Monitoring Stations: 2 sites (each
    pollutant measured at one site only)
    
    Copollutant: PM25, Sulfate, Nitrate,
    OC, EC, N02, CO, S02,  03
    PM Increment: IQR (1-day avg: 32.7
    2-day avg: 34.5
    3-day avg: 26.0)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change in health endpoint per
    increase in IQR of PM10 (1-3 day
    averaging period
    single pollutant models)
    
    hs-CRP:  1-day: 135.8 (1.8, 269.7)
    2-day: 108.2 (-10.9, 227.3)
    3-day: 109.6 (2.5, 216.7)
    
    8-OHdG:1-day:-9.2(-21.5, 3.2)
    2-day:-6.1 (-17.0, 4.8)
    3-day:-5.6 (-13.8, 2.6)
    
    PAI-1:1-day: 30.0 (12.4, 47.7)
    2-day: 19.1  (3.6, 34.7
    3-day: 21.2 (9.7, 32.8
    
    tPA:1-day: 16.0 (-4.1,36.2)
    2-day: 10.4 (-6.3, 27.2)
    3-day: 8.8 (-2.8, 20.5)
    
    Fibrinogen: 1-day: 5.3 (1.5,15.2)
                                                                                                                 2-day: 1.5
                                                                                                                 3-day: 3.3
                                                   -4.4, 7.5)
                                                   -1.1,7.7)
                                                                                                                  Heart Rate Variability
                                                                                                                  SDNN: 1-day:-4.9 (-7.8,-2.1)
                                                                                                                  2-day:-4.0 (-6.6,-1.4)
                                                                                                                  3-day:-4.1 (-6.1,-2.2)
    
                                                                                                                  r-MSSD: 1-day:-4.8 (-12.3, 2.7)
                                                                                                                  2-day: -2.2 (-9.0, 4.7)
                                                                                                                  3-day: -4.0 (-9.0, 0.9)
    
                                                                                                                  LF: 1-day:-6.1 (-10.1,-2.1)
                                                                                                                  2-day:-3.0 (-7.2,1.2)
                                                                                                                  3-day:-4.3 (-7.0,-1.6)
    
                                                                                                                  HF: 1-day:-5.5 (-13.0, 2.1)
                                                                                                                  2-day:-2.7 (-9.5, 4.1)
                                                                                                                  3-day: -2.0 (-7.2, 3.2)
    December 2009
                                      E-4
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Ebelt et al. (2005, 0569071
    
    Period of Study: Summer of 1998
    
    Location: Vancouver, Canada
    Outcome: CVD
    
    Age Groups: Range from 54-86 yr
    mean age= 74 yr
    
    Study Design: Extended analysis of a
    repeated-measures panel study
    
    N: 16 persons with COPD
    
    Statistical Analyses:
    Earlier analysis expanded by
    developing mixed-effect regression
    models and by evaluating additional
    exposure indicators
    
    Dose-response Investigated? No
    
    Statistical Package: SASV8
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD):
    Ambient PM10:17 + 6
    Exposure to ambient PMi0:10.3 ± 4.6
    
    Range (Min, Max):
    Ambient PM10.2.5:7-36
    Exposure to ambient PM10-2s:
    1.5-23.8
    
    Monitoring Stations: 5
    
    Copollutant (correlation):
    Ambient concentrations and exposure
    to ambient PM were highly correlated
    for each respective metric: r > 0.71
    
    PM10.2.5:r >0.72
    
    PM25:r >0.92
    Note: Total personal fine particle
    exposure (T) were dominated by
    exposures to non ambient particles
    which were not correlated with ambient
    fine particle exposure (A) or ambient
    concentrations (C). Results for each of
    these metrics are listed.
    
    Effect estimates and 96% Cl for IQR
    range increases in exposure
    
    Increment: C10: IQR = 7 pg/m3
    SBP (mm Hg): -2.2 (-4.78-0.38)
    DBP (mm Hg):-0.78 (-2.65-1.09)
    Ln-SVE(bph): 0.16 (-0.07-0.40)
    HR(bpm): 1.02 (-0.79-2.82)
    SDNN(ms):-2.14 (-6.94-2.65)
    R-MSSD(ms):-2.24 (-4.27-0.21)
    
    Increment: A10: IQR = 6.5|jg/m3
    SBP (mm Hg): -2.81 (-5.67-0.05)
    DBP (mm Hg):-0.59 (-2.79-1.62)
    Ln-SVE (bph): 0.27 (0.03-0.52)
    HR(bpm): 0.86 (-1.61-3.33)
    SDNN(ms):-3.91  (-9.73-1.91)
    R-MSSD(ms):-0.81 (-4.94-3.31)
    Reference: Folino et al. (2009, 1919021
    
    Period of Study: Jun 2006-May 2007
    Location: Padua, Italy
    
    
    
    
    
    
    
    Outcome: HRV & Inflammatory
    Markers
    
    Age Groups: 45-65 yr
    Study Design: Panel
    N: 39 patients w/ myocardial infarction
    Statistical Analyses: Linear
    Regression Model, ANOVA
    
    Covariates: Temperature, relative
    humidity, atmospheric pressure, beta-
    blocker, aspirin, or nitrate consumption,
    smoking habit
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Mean (SD):
    Summer: 46.4 (16.1)
    Winter: 73.0 (30.9)
    Spring: 38.3 (15. 4)
    Monitoring Stations: NR
    Copollutant: PM25, PM025
    
    Co-pollutant Correlation: NR
    
    PM Increment: 1 pg/m3
    
    Beta (SE), p-value:
    SDNN: 0.115 (0.093), 0.218
    SDANN' 0138 (0103) 0182
    RMSSD: 0.049 (0.034), 0.146
    pH: 0.002 (0.001), 0.033
    LTB4: 0.427 (0.0279), 0.126
    eNO: 0.000 (0.002), 0.851
    PTX3: -0.003 (0.001), 0.033
    C-reactive protein: -0.006 (0.004),
    0.161
    CC16: -0.002 (0.002), 0.280
    IL-8: 0.000 (0.003), 0.895
                                       Dose-response Investigated? No
    
                                       Statistical Package: Stata
    
                                       Lags Considered: NR
    Reference: Forbes et al. (2009,
    1903511
    Period of Study: 1994,1998, 2003
    
    Location: England
    Outcome: Inflammation markers
    
    Age Groups: 16+yr
    
    Study Design: Cross-sectional
    
    N: 25,000 white adults w/fibrinogen
    measurements & 17,000 white adults w/
    C-reactive protein measurements
    
    Statistical Analyses: Multilevel Linear
    Regression Models
    
    Covariates: Age,  sex,  BMI, social
    class, region, cigarette smoking
    
    Dose-response Investigated?  No
    
    Statistical Package: Stata
    
    Lags Considered: NR
    Pollutant: PM10
    
    Averaging Time: Yearly
    
    1994
    Median: 19.5
    Range: 12.5-36.1
    IQR: 3.7
    1998
    Median: 17.9
    Range: 12.6-27.0
    IQR: 2.7
    2003
    Median: 16.2
    Range: 11.0-22.7
    IQR: 2.6
    
    Monitoring Stations: NR
    
    Copollutant: N02, S02, 03
    
    Co-pollutant Correlation: N/A
    PM Increment: 1 pg/m
    
    Percent Change (Lower Cl, Upper
    Cl):
    
    Fibrinogen
    1994 Crude:-0.068 (-0.367, 0.231)
    1994 Adjusted: 0.080 (-0.164, 0.326)
    1998 Crude:-0.592 (-0.902,-0.280)
    1998 Adjusted: -0.388 (-0.727, -0.047)
    2003 Crude:-0.339 (-0.696, 0.019)
    2003 Adjusted: -0.069 (-0.458, 0.322)
    Combined:-0.077 (-0.254, 0.100)
    
    C-reactive protein
    1998 Crude:-0.914 (-2.206, 0.395)
    1998 Adjusted:-0.266 (-1.782, 1.274)
    2003 Crude: 0.286 (-1.327, 1.925)
    2003 Adjusted: 0.661(-1.068, 2.421)
    Combined: 0.140 (-1.003,1.296)
    December 2009
                                     E-5
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Kaufman (1987, 1909601
    Period of Study: Nov 2004-2005
    
    Location: Isfahan, Iran
    
    
    
    Outcome: Inflammation
    Age Groups: 10-18 yr
    
    Study Design: Panel
    N: 374 children
    Statistical Analyses: Linear
    Regression, Logistic Regression
    Pollutant: PM,0
    Averaging Time: 24 h
    
    Mean (SD): 122.08 (33.63)
    Oth: 11.00
    25th: 86.50
    50th: 153.0
    Tfith- •iQ'i nn
    / win • i CM . uu
    PM Increment: NR
    Beta (SE):
    CRP: 1.5(0.2)
    Ox-LDL:1.4(0.1)
    MDA:1.3(0.1)
    CDE:1.1 (0.1)
    HOMA-IR:1.1(0.3)
    
                                        Covariates: Age, gender, BMI, waist
                                        circumference, healthy eating index,
                                        physical activity level
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: SPSS
    
                                        Lags Considered: 0- to 7-day avg
                                        Monitoring Stations: 3
    
                                        Copollutant: 03, S02, N02, CO
    
                                        Co-pollutant Correlation: NR
    Reference: Liao et al. (2004, 0565901
    
    Period of Study: 1996-1998
    
    Location: ARIC study cohort
    (Washington County, MD
    Forsyth County, NC
    and selected suburbs of Minneapolis,
    Outcome: 5-min HR, HRV indices (HF,
    LF, SDNN)
    
    Study Design: Cross-sectional
    
    Statistical Analyses: Linear regression
    The 4th quarter of the ARIC cohort was
    sampled exclusively from black
    residents of Jackson, MS.
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 24.3 (11.5)
    
    Copollutant:
    03
    CO
    S02
    NO,
    PM Increment: SD
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Estimate (SE)
    HF: -0.06 ms2 (0.018)
    SDNN:-1.03ms (0.31)
    H: 0.32 beats/min (0.158)
    Reference: Liao et al. (2005, 0886771
    
    Period of Study: 1987-1989 baseline
    health exam
    
    Location: 3 centers in the U.S.
    (Forsyth County, NC
    suburbs of Minneapolis, MN
    black residents of Jackson, MS)
    Outcome: Fibrinogen, factor VIII co-
    agulant activity (VIII-C), von Willebrand
    factor (vWF), white blood cell count
    (WBC), and serum albumin
    
    Age Groups: 45-64 yr
    
    Study Design: Cross-sectional
    
    N: 10,208 participants (7705 for PM)
    
    Statistical Analyses: Multiple  linear
    regression
    
    Covariates: Age, sex, ethnicity-center,
    education,  smoking, drinking status,
    BMI, history of chronic respiratory
    disease, humidity, season, cloud cover,
    and temperature
    
    Dose-response Investigated?
    Yes, examined higher-ordered terms for
    each pollutant
    
    Statistical Package: SASv8.2
    Pollutant: PM10
    
    Averaging Time: 24-h avg (1, 2, and 3
    days prior to the exam)
    
    Mean (SD): 29.9 (29.9)
    
    Mean (SD) within Quartiles:
    Q1-3: 24.0 (6.96)
    04:47.3(10.11)
    
    Copollutant:
    CO, S02, N02, 03
    PM Increment: 1 SD (12.8 pg/m3)
    
    Effect Estimate: Adjusted regression
    coefficient (SE): Fibrinogen (mg/dl):
    0.163(0.755)
    
    Factor VIII-C (%): Non-linear
    association: |3 (PM,o) = -5.30,  p < 0.01
    
    P (PM,o)2 = 0.80, p < 0.05
    
    vWF(%): Diabetics: 3.93 (1.80)
    
    Nondiabetics: -0.54 (0.58)
    
    Albumin (g/dl): CVD: -0.006 (0.003)
    
    Non-CVD: 0.029 (0.017)
    
    p < 0.05
    December 2009
                                     E-6
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95%  Cl)
    Reference: Liao et al. (2007, 1802721 Outcome: Ectopy
    Period of Study: 1999-2004 Age Groups: Women 50-79 yr
    Location: 24 U.S. states Study Design: Panel
    
    N: 57,422
    Statistical Analyses: Logistic
    regression & random effects modeling
    Covariates: Age, race, center,
    education, history of CVD/chronic lung
    disease, rel. humidity, temperature,
    smoking
    Pollutant: PM,0
    Averaging Time: Daily
    Mean (SD)*:
    All: 27.5 (12.1)
    No Ectopy: 27.5 (12.1)
    Any Ectopy: 27.5 (11. 9)
    6th, 96th percentile*:
    All: 12.2, 48.9
    No Ectopy: 12.3, 48.8
    Any Ectopy: 11.8,49.3
    Monitoring Stations: NR|
    PM Increment: 10 pg/m3
    Percent Change (Lower Cl, Upper
    Cl):
    
    All Ventricular Ectopy
    Lag 0:1. 01
    Lag 1:1. 02
    Lag 2: 0.99
    Current Smc
    Lag 0:1. 21
    Lag 1:1. 32
    Lag 2: 1.22
    0.95, 1.07)
    0.96, 1.09)
    0.93, 1.06)
    )ker Ventricular Ectopy
    0.96, 1.53)
    1.07, 1.65)
    0.95, 1.56)
                                        Dose-response Investigated? No
    
                                        Statistical Package: SAS, Stata
    
                                        Lags Considered: Lags 0-365 day
    
                                        I Monitors used in model for spatial
                                        interpolation of daily PM values.
                                         Copollutant: PM25
    
                                         Co-pollutant Correlation: NR
    
                                         *Lag1
                                         Nonsmoker Ventricular Ectopy
                                         Lag 0:1 (0.93,1.06)
                                         Lag 1:1.01
                                         Lag 2: 0.98
               0.94, 1.07)
               0.92, 1.05)
                                                                             All Supraventricular Ectopy
                                                                             Lag 0:1 (0.95,1.06)
                                                                             Lag 1:1 (0.95,1.05)
                                                                             Lag 2: 0.99 (0.94, 1.04)
    
                                                                             All Ventricular or Supraventricular
                                                                             Ectopy
                                                                             Lag 0:1 (0.95,1.04)
                                                                             Lag 1:1 (0.96,1.04)
                                                                             Lag 2: 0.98 (0.94, 1.02)
    Reference: Liu et al. (2007,1567051
    
    Period of Study:
    May 2005-Jul 2005
    
    Location: Windsor, Ontario, Canada
    Outcome: Heart rate, blood pressure,
    brachial arterial diameter, flow-mediated
    vasodilatation (FMD), plasma cytokines,
    and thiobarbituric acid reactive
    substances (TEARS)
    
    Age Groups: 18-65yr
    
    Study Design: Panel
    
    N: 24 nonsmoking subjects with type I
    or II diabetes over a 7 week period (2-
    14 visits for subjects)
    
    170 total vascular measurements and
    134 total blood samples collected
    
    Statistical Analyses: Mixed effects
    regression models
    
    Covariates: (Time-dependent
    covariates) Daily temperature, relative
    humidity, blood glucose level, also
    checked for confounding by ambient air
    pollutant concentrations (controlled for
    ambient PM25)
    
    Season: No adjustment since testing
    was completed within a 7-wk period
    during early summer
    
    Dose-response Investigated? No
    
    Statistical Package: S-Plus
    Pollutant: PM10 (personal)
    
    Averaging Time: Real-time monitor
    measured exposure during 24-h period
    prior to clinic measures
    
    Median (6th-96th percentile):
    0-24 h: 25.5 (9.8-133.0)
    0-6 h: 15.3 (5.3-83.2)
    7-12 h: 17.0 (7.1-186.3)
    13-18 h: 28.5 (11.4-167.0)
    19-24 h: 30.5 (10.1-148.2)
    
    Monitoring Stations:
    Personal  monitoring
    
    Copollutant (correlation):
    Ambient PM25 (r = 0.34)
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    **p < 0.05
    *p < 0.10. Regression coefficients (SE)
    
    End-diastolic basal diameter (urn): All
    subjects (n=24): -2.52 (3.27)
    subjects not taking vasoactive meds
    (n=17): -3.93 (3.66)
    subjects w/BMI < 29kg/m2 (n=14):  8.85
    (5.85)
    
    End-systolic basal diameter (urn): All
    subjects (n=24): -9.02 (3.58)**
    subjects not taking vasoactive meds
    (n=17): -10.59 (4.36)**
    subjects w/BMI <29kg/m2 (n=14): 3.85
    (5.49)
    
    End-diastolic FMD (%): All subjects
    (n=24): 0.20 (0.08)**
    subjects not taking vasoactive meds
    (n=17): 0.23 (0.09)**
    subjects w/BMI <29kg/m2 (n=14): 0.12
    (0.05)**
    
    End-systolic FMD (%): All subjects
    (n=24): 0.38 (0.18)**
    subjects not taking vasoactive meds
    (n=17):0.51 (0.22)**
    subjects w/BMI <29kg/m2 (n=14):  0.18
    (0.10)*
    
    Flow (cm/s): All subjects (n=24): -0.16
    (0.19)
    subjects not taking vasoactive meds
    (n=17): -0.48 (0.21)**
    subjects w/BMI < 29kg/m2 (n=14):  -0.39
    (0.23)*
    
    Heart rate (bpm): All subjects (n=24):
    0.01 (0.11)
    subjects not taking vasoactive meds
    (n=17): -0.06 (0.12)
    subjects w/BMI <29kg/m2 (n=14):  0.15
    (0.12)
    
    Diastolic blood pressure (mm Hg): All
    subjects (n=24): 0.19 (0.16)
    subjects not taking vasoactive meds
    December 2009
                                      E-7
    

    -------
                  Study                        Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                 (n=17): 0.40 (0.18)**
                                                                                                                 subjects w/BMI < 29kg/m2 (n=14): 0.27
                                                                                                                 (0.21)
    
                                                                                                                 Systolic blood pressure (mm Hg): All
                                                                                                                 subjects (n=24): 0.17 (0.19)
                                                                                                                 subjects not taking vasoactive meds
                                                                                                                 (n=17): 0.43 (0.24)*
                                                                                                                 subjects w/ BMI < 29kg/m2 (n=14): 0.38
                                                                                                                 (0.24)
    
                                                                                                                 CRP (ug/mL): All subjects (n=24): 0.11
                                                                                                                 (0.07)
                                                                                                                 subjects not taking vasoactive meds
                                                                                                                 (n=17): 0.10 (0.09)
                                                                                                                 subjects w/ BMI < 29kg/m2 (n=14): 0.02
                                                                                                                 (0.03)
    
                                                                                                                 ET-1 (pg/mL): All subjects (n=24): 0.00
                                                                                                                 (0.00)
                                                                                                                 subjects not taking vasoactive meds
                                                                                                                 (n=17): 0.00 (0.00)
                                                                                                                 subjects w/BMI < 29kg/m2 (n=14): 0.00
                                                                                                                 (0.01)
    
                                                                                                                 IL-6 (pg/mL): All subjects (n=24): 0.00
                                                                                                                 (0.05)
                                                                                                                 subjects not taking vasoactive meds
                                                                                                                 (n=17):0.01 (0.05)
                                                                                                                 subjects w/BMI < 29kg/m2 (n=14): -0.00
                                                                                                                 (0.03)
    
                                                                                                                 TNF-a (pg/mL): All subjects (n=24):
                                                                                                                 0.03 (0.05)
                                                                                                                 subjects not taking vasoactive meds
                                                                                                                 (n=17): 0.02 (0.05)
                                                                                                                 subjects w/ BMI < 29kg/m2 (n=14): 0.03
                                                                                                                 TEARS (pmol/mL) All subjects (n=24):
                                                                                                                 16.12(4.00)**
                                                                                                                 subjects not taking vasoactive meds
                                                                                                                 (n=17): 8.10 (9.18)
                                                                                                                 subjects w/ BMI < 29kg/m2 (n=14): -
                                                                                                                 0.28 (6.60)
    
                                                                                                                 regression coefficients (SE) among
                                                                                                                 subjects not taking vasoactive
                                                                                                                 medications, with lag time
    
                                                                                                                 End-diastolic basal diameter (urn): 0-
                                                                                                                 6 h: 29.91 (10.64)**
                                                                                                                 7-12 h: 0.72 (3.95)
                                                                                                                 13-18 h:-3.62 (2.80)
                                                                                                                 19-24 h:-0.57 (1.7)
    
                                                                                                                 End-systolic basal diameter (urn): 0-6
                                                                                                                 h: 28.88 (11.22)**
                                                                                                                 7-12 h:-0.78 (4.58)
                                                                                                                 13-18 h:-7.70 (3.30)**
                                                                                                                 19-24 h: -2.87 (2.05)
    
                                                                                                                 End-diastolic FMD(%): 0-6 h:-0.12
                                                                                                                 (0.10)
                                                                                                                 7-12 h: 0.04 (0.05)
                                                                                                                 13-18 h: 0.11  (0.03)**
                                                                                                                 19-24 h: 0.12  (0.04)**
    
                                                                                                                 End-systolic FMD(%): 0-6 h: 0.36
                                                                                                                 (0.08)**
                                                                                                                 7-12 h: 0.48 (0.32)
                                                                                                                 13-18 h: 0.19  (0.06)**
                                                                                                                 19-24 h: 0.34  (0.13)**
    
                                                                                                                 Flow (cm/s):  0-6 h:-0.34 (0.22)
                                                                                                                 7-12 h:-0.26 (0.27
                                                                                                                 13-18 h:-0.27 (0.15)*
                                                                                                                 19-24 h:-0.30 (0.11)**
    
                                                                                                                 Heart rate (bpm): 0-6 h: 0.31 (0.13)**
                                                                                                                 7-12 h: 0.26 (0.12)**	
    December 2009                                                     E-8
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                13-18 h: 0.01 (0.09)
                                                                                                                19-24 h: -0.08 (0.05)
    
                                                                                                                Diastolic blood pressure (mm Hg): 0-
                                                                                                                6 h:-0.29 (0.12)**
                                                                                                                7-12 h: 0.24 (0.12)**
                                                                                                                13-18 h: 0.46 (0.17)**
                                                                                                                19-24 h: 0.18 (0.14)
    
                                                                                                                Systolic blood pressure (mm Hg): 0-
                                                                                                                6 h:-0.65 (0.18)**
                                                                                                                7-12 h: 0.17 (0.19)
                                                                                                                13-18 h: 0.86 (0.24)**
                                                                                                                19-24 h: 0.11 (0.10)
    
                                                                                                                CRP (ug/mL): 0-6 h: 0.15 (0.13)
                                                                                                                7-12 h: 0.15 (0.13)
                                                                                                                13-18 h: 0.03 (0.06)
                                                                                                                19-24 h: 0.04 (0.03)
    
                                                                                                                ET-1 (pg/mL): 0-6 h: 0.02 (0.00)**: 7-12
                                                                                                                h: -0.00 (0.00)
                                                                                                                13-18 h:-0.00 (0.00)
                                                                                                                19-24 h: 0.00 (0.00)
    
                                                                                                                IL-6 (pg/mL): 0-6 h: 0.03 (0.06)
                                                                                                                7-12 h: 0.00 (0.06)
                                                                                                                13-18 h: 0.02  0.03
                                                                                                                19-24 h: 0.00  0.02
    
                                                                                                                TNF-a (pg/mL): 0-6 h: 0.01 (0.07)
                                                                                                                7-12 h: 0.09 (0.04)**
                                                                                                                13-18 h: 0.01 (0.04)
                                                                                                                19-24 h: -0.00 (0.03)
    
                                                                                                                TEARS (pmol/mL): 0-6 h: -4.44 (6.72)
                                                                                                                7-12 h: 11.94 (5.08)**
                                                                                                                13-18 h: 5.06 (4.03)
                                                                                                                19-24 h: 1.06 (4.64)
    
                                                                                                                Note: Adding ambient PM2s data as a
                                                                                                                covariate in the model yielded similar
                                                                                                                regression coefficients for personal
                                                                                                                PM10
    Reference: Lipsett et al. (2006,
    0887531
    Period of Study: Feb-May 2000
    
    Location: Coachella Valley, CA
    Outcome: HRV parameters: SDNN,
    SDANN, r-MSSD, LF, HF, total power,
    triangular index (TRII).
    
    Study Design: Panel study
    
    N: 19 non-smoking adults with coronary
    artery disease
    
    Statistical Analysis: Mixed linear re-
    gression models with random effects
    parameters
    Pollutant: PM10
    
    Averaging Time: 2 h
    
    Mean (range):
    Indio: 23.2 (6.3-90.4)
    Palm Springs: 14 (4.7-52)
    
    Monitoring Stations: 2
    
    Copollutant: 0;
    PM Increment: SE*1000
    
    Effect Estimate (change in HRV per
    unit increase in PM concentration):
    SDNN: -0.71 msec (SE = 0.268)
    
    Notes: Weekly ambulatory 24 h ECG
    recordings (once per week for up to 12
    wk), using Holter monitors, were made.
    Subjects' residences were within 5
    miles of 1 of 2 PM monitoring sites.
    Regressed HRV parameters against 18:
    00-20: 00 mean particulate pollution.
    December 2009
                                      E-9
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Ljungman et al. (2008,
    1802661
    Period of Study: Aug 2001-Dec 2006
    
    Location: Gothenburg & Stockholm,
    Sweden
    Outcome: Ventricular Arrhythmia
    
    Age Groups: 28-85 yr
    
    Study Design: Case-crossover
    
    N: 88 patients w/ implantable
    cardioverter defibrillators
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature, humidity,
    pressure, ischemic heart disease,
    ejection fraction, heart disease,
    diabetes, use of beta-blockers, age,
    BMI, location at time of arrhythmia,
    distance from air pollution monitor
    
    Dose-response Investigated? No
    
    Statistical Package: Stata, S-plus
    
    Lags Considered: Lags 2-24 h
    Pollutant: PM,0
    
    Averaging Time: Hourly
    
    Gothenburg, Stockholm
    
    Median:
    2h: 18.95, 14.62
    24 h: 19.92, 15.23
    
    Min:
    2h: 0.00, 0.33
    24 h: 2.13, 3.96
    
    Max:
    2h: 203.75, 159.79
    24 h: 78.01, 90.50
    
    IQR:
    2h: 14.16, 11.59
    24 h: 11.49, 9.59
    
    Monitoring Stations: 2
    
    Copollutant: PM25, N02
    
    Co-pollutant Correlation
    2 h N02: 0.36
    24 h N02: 0.29
    PM Increment: Interquartile Range
    
    Odds Ratio (Lower Cl, Upper Cl):
    2 h: 1.31 (1.00, 1.72)
    24 h: 1.24 (0.87, 1.76)
    
    Notes: OR of ventricular arrhythmia for
    an IQR increase of air pollutants in
    different subgroups (Fig 2)
    Reference: Ljungman et al. (2009,
    1919831
    Period of Study: May 2003-Jul 2004
    
    Location:
    Athens, Greece
    Helsinki, Finland
    Ausburg, Germany
    Barcelona, Spain
    Rome, Italy
    Stokholm, Sweeden
    Outcome: lnterleukin-6 Response
    
    Age Groups: 35-80 yr
    
    Study Design: Panel
    
    N: 955 male myocardial infarction
    survivors
    
    Statistical Analyses: Additive Mixed
    Models
    
    Covariates: Age, sex, BMI, city,
    HDL/total cholesterol, smoking,
    alcohol intake, HbA1c, NT-proBNP,
    history of Ml, heart failure, or
    diabetes, phlegm
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 1 day
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean: 31.6
    25th: 21.1
    76th: 38.4
    
    Monitoring Stations: NR
    
    Copollutant: CO, N02, PNC, PM25
    
    Co-pollutant Correlation
    PM25: 0.81
    PM Increment: Interquartile Range
    (17.4 pg/m3)
    
    Change of IL-6 (Lower Cl, Upper Cl),
    p-value:
    0.0 (-1.3, 1.3), 1.0
    Reference: Mar et al. (2005, 0875661
    
    Period of Study:  1999-2001
    
    Location: Seattle, WA
    Outcome: Change in arterial 02 satura-
    tion, heart rate, and blood pressure
    (SBP and DBP)
    
    Age Groups: >75 yr
    
    Study Design: Panel study
    
    N: 88 elderly subjects
    
    Statistical Analysis: GEE
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD):
     Indoor: 12.6 (7.8)
    Outdoor: 14.5 (7.0)
    PM Increment: 10 pg/m
    
    Unit change in measure(96% Cl):
    Among all subjects:
    Each increase in outdoor same day
    PM10 was associated with: SBP: -0.10
    mmHg(95%CI:-1.37,1.18)
    
    DBP: -0.03 mmHg (95% Cl: -0.79, 0.73)
    
    HR: -0.48 beats/min (95% Cl: -1.03,
    0.06)
    
    Each increase in indoor same day
    PM25was associated with: SBP: 0.92
    mmHg (95% Cl:-0.95, 2.78)
    
    DBP: 0.63 mmHg (95% Cl:-0.29,1.56)
    
    HR: 0.02 beats/min (95% Cl: -0.54,
    0.58)
    
    Notes: Results by health status
    presented in Fig 1. Used 2 sessions
    that each were  10 consecutive days of
    measurement. Used personal, indoor,
    and outdoor measures of PM2 5
    December 2009
                                    E-10
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Metzger et al. (2007,
    0928561
    
    Period of Study: Jan 1993-Dec 2002
    
    Location: Atlanta, GA
    Outcome: Days with any event
    recorded by the [CD, days with [CD
    shocks/defibrillation and days with
    either cardiac pacing or defibrillation
    
    Study Design: Repeated measures
    
    N: 884 subjects
    
    Statistical Analysis: Logistic
    regression with GEE to account for
    residual autocorrelation within subjects
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 28.0 (12.2)
    
    Median: 26.4
    
    Copollutant:
    03, N02, CO, S02. Aug1998-Dec2002:
    Oxygenated hydrocarbons
    PM Increment: OR (96% Cl):
    
    Outcome = Any event recorded by ICD
    
    OR = 1.00 (95% 0:0.97,1.03)
    Reference: Min et al. (2008,1919011
    
    Period of Study: Dec 2003-Jan 2004
    
    Location: Taein  Isalnd, South Korea
    Outcome: Heart Rate Variability
    
    Age Mean (SD): 44.3 (21.9)
    
    Study Design: Panel
    
    N: 1.349 participants
    
    Statistical Analyses: Linear
    Regression
    
    Covariates: Age, sex, BMI, smoking
    
    Dose-response Investigated? No
    
    Statistical Package: SAS, R
    
    Lags Considered: 0-72 h
    Pollutant: PM,0
    
    Averaging Time: 1 h
    
    Mean (SD): 33.244 (19.017)
    
    Percentiles:
    25th: 18.000
    50th: 26.000
    75th: 41.000
    
    Range: 187.000.16.000
    
    Monitoring Stations: 1
    
    Copollutant: N02, S02
    PM Increment: 1 SD (19 pg/rri)
    
    Percent Change: [Lower Cl, Upper
    Cl]:
    
    SDNN
    6-h avg: -4.34 (-7.99, -0.55 **
    9-havg:-5.48 (-9.61,-1.17 **hA
    12-h avg:-6.23 (-10.47,-1.79)***
    24-h-avg: -4.73 (-9.73, 0.56)-
    48-h avg:-1.25 (-5.59, 3.29)
    72-h avg: -0.85 (-5.35, 3.86)
    
    LF
                                                                                                                6-h avg:-10.32
                                                                                                                9-havg:-13.79
                  -18.05,-1.86)*1
                  -22.26, -4.39)*1
                                                                                                                12-h avg:-14.48 (-23.18, -4.80)*1
                                                                                                                24-h-avg:-13.15 (-23.36,-1.57)*'
                                                                                                                48-h avg:-0.10 (-9.99,10.87)
                                                                                                                72-h avg:-7.61 (-17.04, 2.88)
    
                                                                                                                HF
                                                                                                                6-h avg:-1.07  (-10.43, 9.28)
                                                                                                                9-havg:-3.28  (-13.72, 8.43)
                                                                                                                12-h avg:-4.06 (-14.77, 8.00)
                                                                                                                24-h-avg:-1.22 (-13.96,13.41)
                                                                                                                48-h avg: -3.55
                                                                                                                72-h avg: -3.88
                                                                                          -14.01,8.18
                                                                                          -14.64, 8.23
                                                                                                                Notes: Percent change in HRV for air
                                                                                                                pollution children, adults, and the
                                                                                                                elderly (Fig 2)
    
                                                                                                                Percent change in HRV for PMi0
                                                                                                                exposure in all ages (Fig 3)
    December 2009
                                     E-11
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Peters et al. (2009,
    1919921
    
    Period of Study: May 2003-Jul 2004
    
    Location:
    Helsinki, Finland
    Ausburg, Germany
    Barcelona, Spain
    Rome, Italy
    Stokholm, Sweeden
    Outcome: Plasma Fibrinogen
    
    Age Groups: 37-81
    
    Study Design: Panel
    
    N: 854 adults
    
    Statistical Analyses: Additive Mixed
    Models
    
    Covariates: Age, sex, BMI, city,
    HDL/total cholesterol, smoking,
    HbA1c,  NT-proBNP, history of
    arrhythmia, asthma, arthrosis, stroke,
    bronchitis, season, apparent
    temperature, relative humidity,
    weekday, hour of visit
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 0- to 5-day avg
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 30.3
    
    Min:0
    
    Max: 194
    
    Monitoring Stations: NR
    
    Copollutant: PM25, PM10-25
    
    Co-pollutant Correlation: NR
    PM Increment: 13.5 pg/m
    
    Change (Lower Cl, Upper Cl):
    
    Genotype 1 1
    rs2070006:1.22 (0.47, 1.96)
    rs2070011:1.16 (0.41, 1.90)
    rs1800790: 0.27 (-0.36, 0.91)
    rs2227399: 0.27 (-0.36, 0.91)
    rs6056: 0.19 (-0.45, 0.83
    rs4220: 0.19 (-0.45, 0.83
    Haplotype in cluster 2: 0.09 (-0.53,
    0.76)
    rs1800791: 0.18 (0.21, 1.40)
    
    Genotype 1 2
    rs2070006:0.5(-0.19, 2.15)
    rs2070011: 0.42 (-0.28, 1.13)
    rs1800790:1.28 (0.54, 2.01)
    rs2227399:1.28 (0.55, 2.02)
    rs6056:1.26 (0.49, 2.04
    rs4220:1.27 (0.49, 2.04
    Haplotype in cluster 2:1.17(0.35,1.S
    rs1800791: 0.40 (-0.48, 1.28)
    
    Genotype 2 2
                                                                                                                rs2070006:0.11
                                                                                                                rs2070011:0.08
                                                                                           -1.94,2.15)
                                                                                           -2.08, 2.24)
                                                                                                                rs1800790: 2.15 (0.71, 3.60)
                                                                                                                52227399:2.18(0.73,3.63)
                                                                                                                S6056: 2.24 (0.72, 3.77)
                                                                                                                S4220: 2.25 (0.73, 3.78)
                                                                                                                Haplotype in cluster 2: 2.16 (0.61, 3.71)
                                                                                                                rs1800791:-0.13 (-1.84, 1.58)
    Reference: Rosenlund et al. (2007,
    1146791
    
    Period of Study: 1985-1996
    
    Location: Stockholm County
    Outcome: Myocardial Infarction
    
    Age Groups: 15-79yr
    
    Study Design: Case-control
    
    N: 24,387 first event of myocardial
    infarction cases and 276,926 population
    based controls
    
    Statistical Analyses: Logistic
    Regression
    
    Covariates: Age, sex, calendar yr, SES
    
    Dose-response Investigated? No
    
    Statistical Package: Stata
    
    Lags Considered: 5 yr
    Pollutant: PM,0
    
    Averaging Time: 5 yr
    
    Median: 2.4
    
    6th-96th: 0.3-6.2
    
    Median: 2.2
    
    5th-95th: 0.3-6.0
    
    Monitoring Stations: NR
    
    Copollutant: N02, CO
    
    Co-pollutant Correlation: HNR
    PM Increment:
    5th-95th percentile (5|jg/m3)
    
    Odds Ratio (Lower Cl, Upper Cl):
    
    All Subjects
    Controls: 1.0
    All Cases: 1.04 (1.00,1.09)
    Nonfatal Cases: 0.98 (0.963,1.03)
    Fatal Cases: 1.16 (1.09,1.24)
    In-hospital death:  1.05 (0.95,1.17)
    Out-of-hospital death: 1.23(1.14,1.33)
    
    Subjects who did not move b/t
    population censuses
    Controls: 1.0
    All Cases: 1.11 (1.02,1.21)
    Nonfatal Cases: 1.05 (0.96,1.15)
    Fatal Cases: 1.56 (1.28,1.91)
    In-hospital death:  1.58 (1.13, 2.19)
    Out-of-hospital death: 1.56(1.22,1.98)
    December 2009
                                     E-12
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Ruckerl et al. (2007,
    1569311
    Outcome: lnterleukin-6 (IL-6),
    fibrinogen, C-reactive protein (CRP)
    Period of Study: May 2003-Jul 2004   Age Groups: 35-80 yr
    Location: Athens, Augsburg,
    Barcelona, Helsinki, Rome, and
    Stockholm
    Study Design: Repeated measures/
    longitudinal
    
    N: 1003 Ml survivors
    
    Statistical Analyses: Mixed-effect
    models
    
    Covariates: City-specific confounders
    (age, sex, BMI) long-term time trend
    and apparent temperature RH, time of
    day, day of week included if adjustment
    improved  model fit
    
    Season: Long-term time trend
    
    Dose-response Investigated? Used p-
    splines to allow for nonparametric
    exposure-response functions
    
    Statistical Package: SASv9.1
    Pollutant: PM,0
    
    Averaging Time: Hourly and 24 h (lag
    0-4, mean of lags 0-4, mean of lags 0-1,
    mean of lags 2-3, means of lags 0-3)
    
    Mean (SD): Presented by city only
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: Central
    monitoring sites in each city
    
    Copollutant:
    S02
    03
    NO
    NO,
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change in mean blood markers per
    increase in IQR increase of air pollutant.
    
    IL-6: Lag (IQR): % change in GM
    (95%CI)
    Lag 0(17.4):-0.34 (-1.66, 0.99)
                                                                                                               Lag1
                                                                                                               Lag 2
          17.4):-0.69
          17.4):-1.59
    -1.95,0.58
    -3.99, 0.88
                                                                                                               5-day avg (13.5):-0.87 (-2.28, 0.55)
    
                                                                                                               Fibrinogen: Lag (IQR): % change in
                                                                                                               AM (95%CI)
                                                                                                               Lag 0(17.4): 0.06 (-0.43,  0.55)
                                                                                                               Lag 1(17.4): 0.14 (-0.35,  0.63)
                                                                                                               Lag 2 (17.4): 0.24 (-0.24,  0.72)
                                                                                                               5-day avg (13.5): 0.60 (0.10,1.09)
    
                                                                                                               CRP: Lag (IQR): % change in GM
                                                                                                               (95%CI)
                                                                                                               Lag 0(17.4):-0.71 (-2.75, 1.37)
                                                                                                               Lag1
                                                                                                               Lag 2
                                              17.4):-0.63
                                              17.4):-1.42
                     -2.61, 1.39
                     -4.23, 1.47
                                                                                                               5-day avg (13.5):-1.35 (-3.45, 0.79)
    December 2009
                                     E-13
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ruckerl et al. (2006,
    0887541
    Period of Study: Oct 2000-Apr 2001
    
    Location: Erfurt, Germany
    Outcome: C-reactive protein (CRP)
    serum amyloid A (SAA)
    E-selectin
    vWF
    intercellular adhesion molecule-1
    (ICAM-1)
    fibrinogen
    Factor VII
    prothrombin fragment 1+2
    D-dimer
    
    Age Groups: 50+ yr
    
    Study Design: Panel (12 repeated
    measures at 2-wk intervals)
    
    N: 57 male subjects with coronary
    disease
    
    Statistical Analyses: Fixed effects
    linear and logistic regression models
    
    Covariates: Models  adjusted for differ-
    ent factors based on  health endpoint
    CRP: RH, temperature, trend, ID
    ICAM-1: temperature, trend, ID
    vWF: air pressure, RH,  temperature,
    trend,  ID
    FVII: air pressure, RH, temperature,
    trend,  ID, weekday
    
    Season:  Time trend  as covariate
    
    Dose-response Investigated? Sensi-
    tivity analyses examined nonlinear
    exposure-response functions
    
    Statistical Package: SAS v8.2 and
    S-Plusv6.0
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 20.0 (13.0)
    
    Percentiles:
    25th: 10.8
    50th: 15.6
    75th: 26.0
    
    Range (Min, Max): 5.4, 74.5
    
    Monitoring Stations: 1 site
    
    Copollutant:
    UFPs
    AP
    PM25
    PM10
    OC
    EC
    N02
    CO
    PM Increment: IQR (15.2
    5-day avg: 12.8)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Effects of air pollution on blood markers
    presented as OR (95%CI) for an
    increase in the blood marker above the
    90th percentile per increase in IQR air
    pollutant.
    
    CRP: Time before draw: 0-23 h: 1.2
    (0.8,1.9)
    24-47 h: 2.0 (1.1, 3.6
    48-71 h: 2.2 (1.2, 3.8
    5-day mean: 2.0 (1.2, 3.7)
    
    ICAM-1: Time before draw: 0-23 h: 1.3
    (0.9, 1.8)
    24-47 h: 3.1 (2.0, 4.8)
    48-71 h: 3.4 (2.2, 5.2)
    5-day mean: 3.4 (2.2, 5.3)
    
    Effects of air pollution on blood markers
    presented as % change from the
    mean/GM in the blood marker per
    increase in IQR air pollutant.
    
    vWF: Time before draw: 0-23 h: 4.0
    (-0.6, 8.5)
    24-47 h: 6.0 (0.6, 11.5)
    48-71 h:1.1 (-4.9,7.0)
    5-day mean: 6.1 (-0.6,12.8)
    
    FVII: Time before draw: 0-23 h: -6.6
    (-10.4--2.5)
    24-47 h:-8.4 (-12.3--4.3)
    48-71 h: -5.9 (-9.6, -2.0)
    5-day mean:-8.0 (-12.4,-3.4)
    
    Note: Summary of results presented in
    figures. SAA results indicate increases
    in association with PM (not as strong
    and consistent as with CRP)
    
    No association observed between  E-
    selectin and PM
    
    An increase in prothrombin fragment
    1+2 was consistently observed,
    particularly with lag 4
    
    Fibrinogen results revealed few
    significant associations, potentially due
    to chance
    
    D-dimer results revealed null
    associations in linear and logistic
    analyses
    December 2009
                                     E-14
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Ruckerl et al. (2007,
    0913791
    Period of Study: Oct 2000-Apr 2001
    
    Location: Erfurt, Germany
    Outcome: Soluble CD40 ligand
    (SCD40L), platelets, leukocytes,
    erythrocytes, hemoglobin
    
    Age Groups: 50+ yr
    
    Study Design: Panel (12 repeated
    measures at 2-wk intervals)
    
    N: 57 male subjects with coronary
    disease
    
    Statistical Analyses: Fixed effects
    linear regression models
    
    Covariates: Long-term time trend,
    weekday of the visit, temperature, RH,
    barometric pressure
    
    Season: Time trend as covariate
    
    Dose-response Investigated? No
    
    Statistical Package: SAS v8.2 and
    S-Plusv6.0
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 20.0 (13.0)
    
    Percentiles:
    25th: 10.8
    50th: 15.6
    75th: 26.0
    
    Range (Min, Max): 5.4, 74.5
    
    Monitoring Stations: 1 site
    
    Copollutant:
    UFPs
    AP
    PM25
    PM10
    NO
    PM Increment: IQR (15.2
    
    5-day avg: 12.8)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Effects of air pollution on blood markers
    presented as % change from the
    mean/GM in the blood marker per
    increase in IQR air pollutant.
    
    SCD40L,  % change GM (pg/mL): lagO:
    1.6 (-3.5,  7.0)
    lag 1:1.1  (-5.4,7.9)
    lag 2: -3.5 (-8.9, 2.2)
    lag 3:-1.4 (-6.0, 3.4)
    5-day mean:-1.2 (-7.8, 5.8)
    
    Platelets, % change mean (103/ul):
    lag 0:-0.4 (-1.9,1.0)
    lag 1:0.4 (-1.4, 2.3)
    lag 2: 0.5 (-1.4, 2.3)
    lag 3:-0.1 (-1.6,1.4)
    5-day mean: 0.0 (2.1, 0.0)
    
    Leukocytes, % change in mean
    (103/ul): lagO:-1.1 (-2.8,0.7)
    lag 1:-0.5 (-2.6,1.5)
    lag 2: 0.1  (-2.1,2.4)
    lag 3:-0.7 (-2.6,1.2)
    5-day mean:-1.1 (-3.6,1.4)
    
    Erythrocytes, % change mean
    (106/ul): lagO: 0.0 (-0.4, 0.5)
    lag 1:-0.4 (-1.0, 0.1)
    
    
    Reference: Steinvil et al. (2008,
    1888931
    
    Period of Study: 2003-2006
    Location: Tel-Aviv, Israel
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Inflammation
    Age Groups:
    Mean(SD):46(12)yr
    Study Design: Panel
    N1 ?fi^Q
    • \j\j\jy
    Statistical Analyses: Linear
    Regression
    Covariates: Age, waist circumference,
    BMI, HDL, OLDL, triglycerides, diastolic
    & systolic BP, alcohol consumption,
    sports intensity, medications, smoking
    status, family history of CHD,
    temperature, humidity, precipitation,
    season, & yr
    
    Dose-response Investigated? No
    
    Statistical Package: SPSS
    Lags Considered: 0-7 days
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (SD):
    64 (100.8)
    25th: 33.1
    60th: 43.0
    75th: 60.7
    Monitoring Stations: NR
    Copollutant: S02, N02, 03, CO
    Co-pollutant Correlation:
    S02: 0.043
    N02: 0.082
    03: -0.113
    CO: 0.075
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    lag 2: -0.7 -1.2, -0.2)
    lag 3: -0.4 -0.8, 0.0)
    5-day mean: -0.6 (-1.2, -0.1)
    Hemoglobin, % change mean (g/dl):
    lag 0: -0.1 -0.7,0.6)
    lag 1: -0.4 -1.2,0.3)
    lag 2: -0.7 (-1.3, 0.0)
    lag 3: -0.3 (-0.9, 0.2)
    5-day mean: -0.7 (-1.5, 0.1)
    PM Increment: Interquartile Range
    (27.6 pg/m3)
    
    hs-CRP Relative % Change (Lower
    Cl, Upper Cl):
    Men:
    Lag 0: -1 (-2, 1)
    Lag1:0(-1, 1);Lag2:-1 (-2, 1)
    Lag 3: -1 (-2, 0)
    Lag 4:0 (-1,1)
    Lag 5:0 (-1,2)
    Lag 6: 1 (0, 2)
    Lag 7: 1(0,1)
    0-7 avg: -2 (-5, 1)
    
    V\fomen:
    Lag 0: 0 (-2, 2)
    Lag 1:0(-1, 2)
    Lag 2: 1 (0, 2)
    Lag3:0(-1, 1)
    Laq 4' 0 -1 2
    i_uy -T. w \ i , f-j
    Lag 5:0 (-1,2)
    Lag 6: -1 (-3, 1)
    Lag 7: 0 (-2, 1)
    0-7 avg: 1 (-2, 4)
    Fibrinogen Absolute % Change
    (Lower Cl, Upper Cl):
    Men:
    LagO: 0.7(0.0,1. 5); Lag1:0.4(-0.2, 0.9);
    Lag2:-0.1(-0.9, 0.6)
    Lag3:-0.1(-0.7, 0.6); Lag4: 0.0(-0.7,
    0.7);Lag5:0.1(-0.7, 1.0)
    Laq6:0.6(-0.1, 1.3); Laq7: 0.4(0.0, 0.8);
    December 2009
                                     E-15
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                 0-7avg:-0.4(-1.9,1.0)
    
                                                                                                                 V\fomen:
                                                                                                                 LagO: 0.3(-0.6,1.2); Lag1: -0.1 (-0.8,
                                                                                                                 0.7); Lag2: -0.3(-0.9, 0.3)
                                                                                                                 Lag3:-0.1(-0.7, 0.5); Lag4: 0.2(-0.4,
                                                                                                                 0.9); Lag5: 0.2(-0.7,1.2)
                                                                                                                 Lag6:-0.3(-1.4, 0.8); Lag7:0.7(-0.1,
                                                                                                                 1.5);0-7avg:0.0(-1.5,1.5)
    
                                                                                                                 WBC Absolute Change (Lower Cl,
                                                                                                                 Upper Cl):
    
                                                                                                                 Men:
                                                                                                                 LagO: 2 (-22, 27)
                                                                                                                 Lag1:3(-14,19)
                                                                                                                 Lag2:1 (-22, 24)
                                                                                                                 Lag3:-7(-28,14)
                                                                                                                 Lag4: -22 (-44, -1)
                                                                                                                 Lag5: -20 (-46, 7
                                                                                                                 Lag6:-5(-27,16
                                                                                                                 Lag7:-4(-16, 9)
                                                                                                                 0-7avg:-11(-58, 36)
    
                                                                                                                 V\fomen:
                                                                                                                 Lag 0: 20 (-6, 46)
    Reference: Su et al. (2006,1570221
    
    Period of Study: Feb-Apr 2002
    
    Location: Taipei, Taiwan
    Outcome: Total cholesterol, HDL,
    tryglycerides, LDL, hs-CRP, IL-6, TNF-
    a, tPA, PAI-1, and fibrinogen
    
    Age Groups: 40-75 yr
    
    Study Design: Panel study
    
    N: 49 subjects (31  males and 18
    females) with coronary heart disease or
    multiple risk factors for CHD
    
    Statistical Analysis: Linear mixed
    effects regression
    Pollutant: PM,0
    
    Averaging Time: 1 h
    
    (High pollution day = PM10 from 08:
    00-18: 00 >100)
    
    Copollutant: 0;
    PM Increment: High vs.. Low pollution
    days
    
    Effect Estimate [Lower Cl, Upper Cl]:
    CHD patients (n = 23): P-value for
    paired t-test comparing health endpoint
    means on high and low pollution days
    
    hs-CRP: p = 0.568
    IL-6: p = 0.856
    TNF-a: p = 0.246
    PAI-1: p = 0.008
    tPA: p = 0.322
    
    Fibrinogen: p = 0.189
    P-value for health endpoint in mixed-
    effects models
    PAI-1: p = 0.010
    tPA: p = 0.329
    Fibrinogen: p = 0.747
    
    Patients with multiple CHD risk
    factors (n = 26): P-value for paired t-
    test comparing health endpoint means
    on high and low pollution days
    
    hs-CRP: p = 0.475
    IL-6: p = 0.561
    TNF-a: p = 0.572
    PAI-1: p = 0.098
    tPA: p = 0.260
    
    Fibrinogen: p = 0.087
    P-value for health endpoint in mixed-
    effects models
    PAI-1: p = 0.891
    tPA: p = 0.789
    
    Fibrinogen: p = 0.923
    
    Notes: Subjects had paired fasting
    blood samples taken during high and
    low air pollution days.
    December 2009
                                     E-16
    

    -------
                  Study
                                               Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Vedal et al., (2004, 0556301  Outcome: Implantable cardioverter
    „..,„..   „„„-,„„„,            defibrillator (ICD) discharge
    Period of Study: 1997-2000
    Location: Vancouver, British Columbia
                                        Age Groups: All
    
                                        Study Design: Time series
                                        (Retrospective, longitudinal panel study)
    
                                        N: 50 ICD patients with 1+ discharges
                                        (40,328 person-days and 257
                                        arrhythmia event days)
    
                                        Statistical Analyses: Multiple logistic
                                        regression with GEE
    
                                        Covariates: Temperature, relative
                                        humidity, barometric pressure, rainfall,
                                        wind direction and speed
    
                                        Season: Summer (May-Sep) and winter
                                        (Oct-Apr)
    
                                        Dose-response Investigated: No
    
                                        Statistical Package: NR
    
                                        Lags Considered: -3 day
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (min-max): 12.9 (3.8-49.3)
    SD = 5.6
    
    Monitoring Stations: 8
    
    Copollutant (correlation):
    03:r = 0.11
    S02:r = 0.70
    N02:r = 0.49
    CO: r = 0.43
    
    Other variables:
    Temp: r = 0.43
    Humidity: r = -0.35
    Baro Pressures = 0.26
    Rain: r = -0.63
    Wind:  r = -0.53
    PM Increment: 5.6 pg/m  (SD)
    
    Percent Change [Cl]: Values NR
    
    Notes: The author states that significant
    negative associations were found for
    ICD discharge with same-day lag, and
    also for 3-day lag with more arrhythmia-
    prone patients. All other non-significant
    percent change estimates are shown in
    Fig 3 and 4.
    Reference: Vedal et al. (2004, 0556301   Outcome: ICD discharges
    
    PeriodofStudy:1997-2000
    Location: Vancouver, British Columbia,
    Canada
                                        N: 150 patients w/ICD, 4 yr
    
                                        Statistical Analysis: Logistic
                                        regression, GEE
    
                                        Covariates: Temporal trends,
                                        temperature, relative humidity, wind
                                        speed, rain
    
                                        Season: Summer, winter
    
                                        Dose-response Investigated? No
    
                                        Lags Considered: 0,  1, 2, and 3 days
    Pollutant: PM,0
    
    Mean: 12.9 (SD = 5.6)
    
    Copollutant): 03, S02, N02, CO
    Increment: 1 SD
    
    Effect Estimates, e.g., % change in the
    rate of arrhythmia, were presented in
    Fig 3. No association with PMiq was
    observed while S02 was associated
    with an increase in the rate of
    arrhythmia among 16 patients with at
    least 2 discharges per yr.
    December 2009
                                                                        E-17
    

    -------
                  Study
                                                Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Whitsel et al. (2009,
    1919801
    
    Period of Study: 1993-2004
    
    Location: U.S.
                                        Outcome: Heart Rate Variability
    
                                        Age Groups: 50-79 yr
    
                                        Study Design: Panel
    
                                        N: 4,295 women
    
                                        Statistical Analyses: Random Effects
                                        Model
    
                                        Covariates: Temperature, humidity
    
                                        Dose-response Investigated? No
    
                                        Statistical Package:  SUDAAN
    
                                        Lags Considered: 0
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Amsterdam
    
    Mean: 20.0
    Min:3.8
    26th: 10.4
    50th: 16.9
    76th: 23.9
    Max: 82.2
    
    Erfurt
    
    Mean: 23.1
    Min:4.5
    25th: 10.5
    60th: 16.3
    76th: 27.4
    Max: 118.1
    
    Helsinki
    
    Mean: 12.7
    Min:3.1
    26th: 8.1
    60th: 10.6
    76th: 16.0
    Max: 39.8
    
    Monitoring Stations: 3
    
    Copollutant: NR
    
    Co-pollutant Correlation: N/A
    PM Increment: 10 pg/m
    
    Beta (Lower Cl, Upper Cl):
    
    Supine Position, Amsterdam
    Lag 0: -0.06 (-0.95, 0.84)
                                                                                                                 Lag 1:0.18
                                                                                                                 Lag 2: 0.93
               -0.74, 1.10)
               0.01, 1.85)
                                                                                                                 5-day avg: 0.49 (-0.74,1.72)
    
                                                                                                                 Supine Position, Erfurt
                                                                                                                 Lag 0:-0.36 (-0.83, 0.11)
                                                                                                                 Lag 1:-0.40 (-0.91, 0.11)
                                                                                                                 Lag 2:-0.68 (-1.20,-0.17)
                                                                                                                 5-day avg:-0.68 (-1.44, 0.09)
    
                                                                                                                 Supine Position, Helsinki
                                                                                                                 Lag 0:-0.44 (-2.27, 1.40)
                                                                                                                 Lag 1:-0.17 (-1.69,1.3.5)
                                                                                                                 Lag 2:-1.14 (-2.51, 0.23)
                                                                                                                 5-day avg:-0.59 (-3.08,1.90)
    
                                                                                                                 Supine Position, Pooled
                                                                                                                 Lag 0:-0.30 (-0.71, 0.11)
                                                                                                                 Lag 1:-0.25 (-0.68, 0.18)
                                                                                                                 Lag 2:-0.26 (-1.22, 0.70)*
                                                                                                                 5-day avg:-0.36 (-0.99, 0.27)
    
                                                                                                                 Standing Position, Amsterdam
                                                                                                                 Lag 0:-0.44 (-1.6, 0.72)
                                                                                                                 Lag 1:-0.61 (-1.8,0.59)
                                                                                                                 Lag 2: 0.32 (-0.88, 1.51)
                                                                                                                 5-day avg:-0.55 (-2.15,1.04)
    
                                                                                                                 Standing Position, Erfurt
                                                                                                                 Lag 0:-0.59 (-1.24, 0.06)
                                                                                                                 Lag 1:-0.70 (-1.42, 0.03)
                                                                                                                 Lag 2:-0.65 (-1.37, 0.07)
                                                                                                                 5-day avg:-0.68 (-1.74, 0.39)
    
                                                                                                                 Standing Position, Helsinki
                                                                                                                 Lag 0:1.17 (-1.46, 3.80)
                                                                                                                 Lag 1:0.01 (-2.17,2.19)
                                                                                                                 Lag 2:-0.63 (-2.60, 1.34)
                                                                                                                 5-day avg:-1.96 (-5.51,1.60)
    
                                                                                                                 Standing Position, Pooled
                                                                                                                 Lag 0:-0.48 (-1.03, 0.07)
                                                                                                                 Lag 1:-0.62 (-1.21,-0.03)
                                                                                                                 Lag 2:-0.41 (-1.00, 0.17)
                                                                                                                 5-day avg:-0.72 (-1.57, 0.14)
    
                                                                                                                 *p<0.1
    Period of Study:
    12-wk period b/t Sep 2003-Jul 2004
    
    Location: Chapel Hill, NC
    Reference: Yeatts et al. (2007, 0912661 Outcome: Heart Rate Variability
    
                                        Age Groups: 21-50 yr
    
                                        Study Design: Panel
    
                                        N: 12 asthmatics
    
                                        Statistical Analyses: Linear Mixed
                                        Model
    
                                        Covariates: Temperature, humidity,
                                        pressure
    
                                        Dose-response Investigated? No
    
                                        Statistical Package:  SAS
    
                                        Lags Considered: 1 day
    Pollutant: PM10
    
    Averaging Time: 24 h
    
    Mean (SD): 17.5 (7.8)
    
    Min:1.4
    
    Max: 45.6
    
    Monitoring Stations: 1
    
    Copollutant: PM2.5, PM10.2.5
    
    Co-pollutant Correlation
    PM25 = 0.90*
    PMio-2.5 = 0.73*
    
    *p < 0.01
    PM Increment: 1 pg/m
    
    Beta, SE, p-value (Lower Cl, Upper
    Cl): NR
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                                                                          E-18
    

    -------
    Table E-2.      Short-term exposure - cardiovascular morbidity studies: PMio25.
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Chuang et al. (2007,
    0910631
    
    Period of Study: Nov 2002-Mar 2003
    
    Location: Taipei, Taiwan
    Outcome: Heart Rate Variability
    
    Age Groups: 52-76 yr
    
    Study Design: Panel
    
    N: 10 CHD & 16 Hypertensive Patients
    
    Statistical Analyses: Linear Mixed
    Effects Model
    
    Covariates: Age, sex, BMI, time of day,
    temperature, humidity, pressure, HRV
    
    Dose-response Investigated? No
    
    Statistical Package: S-PLUS
    
    Lags Considered: 1- to 4-h ma
    Pollutant: PM10.2.5
    
    Averaging Time: 1 h
    among CHD, among hypertensive
    
    Mean (SD): 16.4 (10.7), 14.0(11.1)
    
    IQR: 14.8, 11.9
    
    Min: 0.7, 0.3
    
    Max: 59.6, 66.5
    
    Monitoring Stations: 1 personal
    monitor each
                                                                           Copollutant: PM,
                       , PM0
                                                                           Co-pollutant Correlation:
                                                                           NR
    PM Increment: Interquartile range
    
    Percent Change (Lower Cl, Upper
    Cl):
    
    Cardiac Patients- SDNN
    1h moving:-1.73 (-3.53, 0.08)
    2h moving:-1.97 (-4.43, 0.49)
    3h moving:-1.70 (-4.39, 0.89)
    4h moving:-1.75 (-5.42,1.92)
    
    Cardiac Patients- r-MSSD
    1h moving:-4.39 (-9.54, 0.03)
    2h moving: -4.36 (-8.99, 0.27)
    3h moving:-4.20 (-9.02, 0.61)
    4h moving: -2.70 (-9.24, 3.84)
    
    Cardiac Patients- LF
    1h moving:-1.85 (-4.33, 0.62)
    2h moving: -3.87 (-8.22, 0.47
    3h moving: -2.98 (-6.65, 0.69)
    4h moving:-3.11 (-8.22,1.99)
    
    Cardiac Patients- HF
    1h moving:-4.46 (-9.23, 0.32)
    2h moving: -4.41 (-9.55, 0.72)
    3h moving:-3.80 (-9.12,1.53)
    4h moving:-3.39 (-10.62, 3.84)
    
    Cardiac Patients- LF:  HF ratio
    1h moving: 8.45 (-3.48, 20.38)
    2h moving: 1.66 (-15.22,18.55)
    3h moving: 11.69 (-7.27, 30.64)
    4h moving: 8.18 (-17.22, 33.57)
    
    Hypertensive Patients- SDNN
    1h moving:-2.64 (-3.93, 0.55
    2h moving: -3.51 (-7.87, 0.85)
    3h moving: -2.74 (-6.22, 0.74)
    4h moving:-2.49 (-6.13,1.15)
    
    Hypertensive Patients- r-MSSD
    1h moving:-2.53 (-5.10, 0.04)
    2h moving:-5.42 (-10.92, 0.09)
    3h moving:-3.15 (-6.32, 0.03)
    4h moving: -4.23 (-8.88, 0.42)
    
    Hypertensive Patients- LF
    1h moving:-4.38 (-8.78, 0.03)
    2h moving:-5.23 (-10.95, 0.05)
    3h moving:-3.34 (-1.72, 0.04)
    4h moving:-2.96 (-6.63, 0.71)
    
    Hypertensive Patients- HF
    1h moving:-4.92 (-9.94, 0.10)
    2h moving:-6.07 (-12.28, 0.13)
    3h moving:-1.94 (-5.44,1.55)
    4h moving:-2.78 (-6.78,1.21)
    
    Hypertensive Patients- LF: HF ratio
    1h moving: 5.94 (-3.27,15.15)
    2h moving: 10.70 (-2.19, 23.59)
    3h moving:-1.51 (-17.02,14.00)
    4h moving: 3.41 (-16.91, 23.74)
    
    *p < 0.05
    December 2009
                                     E-19
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ebelt et al. (2005, 0569071
    
    Period of Study: Summer of 1998
    
    Location: Vancouver, Canada
    Outcome: CVD
    
    Age Groups: range from 54-86 yr
    mean age= 74 yr
    
    Study Design: extended analysis of a
    repeated-measures panel study
    
    N: 16 persons with COPD
    
    Statistical Analyses:
    Earlier analysis expanded by
    developing mixed-effect regression
    models and by evaluating additional
    exposure indicators
    
    Dose-response Investigated? No
    
    Statistical Package: SASV8
    Pollutant: PM10.2.5
    
    Averaging Time: 24 h
    
    Mean (SD):
    Ambient PM10.2.5: 5.6 (3.0)
    Exposure to ambient PM10.25: 2.4 (1.7)
    
    Range (Min, Max):
    Ambient PMio-25: (-1.2-11.9)
    Exposure to ambient PM10.25: (-0.4-7.2)
    
    Monitoring Stations: 5
    
    Copollutant (correlation):
    Ambient concentrations and exposure
    to ambient PM were highly correlated
    for each respective metric: r > 0.71
    Note: Total personal fine particle
    exposure (T) were dominated by
    exposures to non ambient particles
    which were not correlated with ambient
    fine particle exposure (A) or ambient
    concentrations (C). Results for each of
    these metrics are listed.
    
    PM Increment:
    
    Increment: C10-2.5: IQR = 4.5 pg/m3
    SBP (mm Hg):-2.12 (-5.07-0.82)
    DBP (mm Hg): -0.92 (-3.37-0.36)
    Ln-SVE (bph): 0.06 (-0.24-0.36)
    HR(bpm): 1.09 (-0.69-2.86)
    SDNN(ms): 2.64 (-2.85-8.13)
    R-MSSD (ms): -0.33 (-4.49-3.82)
    
    Increment: A10-2.5: IQR = 2.4 pg/m3
    SBP (mm Hg):-2.55 (-6.15-1.05)
    DBP (mm Hg):-0.75 (-3.50-2.01)
    Ln-SVE (bph): 0.26 (-0.07-0.58)
    HR(bpm): 1.04 (-0.95-3.03)
    SDNN (ms): 0.68 (-3.07-4.42)
    R-MSSD (ms): 1.10 (-3.08-5.28)
    Reference: Lipsett et al. (2006,
    0887531
    Period of Study: Feb-May 2000
    
    Location: Coachella Valley, CA
    Outcome: HRV parameters, specifically  Pollutant: PM10.25
    SDNN, SDANN, r-MSSD, LF, HF, total
    power, triangular index (TRII).           Averaging Time: 2 h
    
    Study Design: Panel study             Monitoring Stations: 2
    
    N: 19 non-smoking adults with coronary  Copollutant: 03
    artery disease
    
    Statistical Analysis: Mixed  linear
    regression models with random effects
    parameters
                                        PM Increment: SE*1000
    
                                        Effect Estimate (change in HRV per
                                        unit increase in PM concentration):
                                        SDNN: -0.72 msec (SE = 0.296)
    
                                        Notes: PM10.2.5 calculated by
                                        subtracting PM25 concentration from
                                        PM10 concentration. Weekly ambulatory
                                        24-h ECG recordings (once per wk for
                                        up to 12 wk), using Holter monitors,
                                        were made. Subjects' residences were
                                        within 5 mi of 1 of 2 PM monitoring
                                        sites. Regressed HRV parameters
                                        against 18: 00-20:  00 mean particulate
                                        pollution
    Reference: Metzger et al. (2007,
    0928561
    Period of Study: Aug 1998-Dec 2002
    
    Location: Atlanta, GA
    Outcome: Days with any event
    recorded by the ICD, days with ICD
    shocks/defibrillation and days with
    either cardiac pacing or defoliation
    
    Study Design: Repeated measures
    
    N: 884 subjects between 1993 and
    2002
    
    Statistical Analysis: Logistic
    regression with GEE to account for
    residual autocorrelation within subjects
    Pollutant: PMio.25 (n/cm3)
    
    Averaging Time: 24 h
    
    Mean (SD): 9.6 (5.4)
    
    Median: 8.7
    
    Copollutant:
    03, N02, CO, S02, oxygenated
    hydrocarbons
    PM Increment: OR (96% Cl):
    OR = 1.03 (95% Cl: 1.00, 1.07)
    Reference: Pekkanen et al. (2002,
    0350501
    
    Period of Study: Winter 1998-1999
    
    Location: Helsinki, Finland
    Outcome: ST Segment Depression
    (>0.1mV)
    
    Study Design: Panel of ULTRA Study
    participants
    
    N: 45 subjects, 342 biweekly
    submaximal exercise tests, 72 exercise
    induced ST Segment Depressions
    
    Statistical Analysis: Logistic
    regression / GAM
    Pollutant: PM10.25 (n/cm3)
    
    Averaging Time: 24 h
    
    Median: 4.8
    
    IQR: 5.5
    
    Monitoring Stations: 1
    
    Copollutant: N02, CO, PM25, PM,,
    ACP, ultrafme
    PM Increment: IQR
    
    Effect Estimate(s): PMio.25: OR = 1.99
    (0.70, 5.67), lag 2
    
    Notes: The effect was strongest for
    ACP and PM25, which in 2 pollutant
    models appeared independent.
    Increases in N02 and CO were also
    associated with increased risk of ST
    segment depression,  but not with
    coarse particles.
    Reference: Timonen et al. (2006,
    0887471
    Period of Study: 1998-1999
    
    Location Amsterdam, Netherlands
    Erfurt, Germany
    Helsinki, Finland
    Outcome: HRV measurements: [LF,
    HF, LFHFR, NN interval, SDNN, r-
    MSSD]
    
    Study Design: Panel study
    
    N: 131 elderly subjects with stable
    coronary heart disease
    
    Statistical Analysis: Linear mixed
    models
    Pollutant: PMio.25
    
    Means:
    Amsterdam: 15.3
    Erfurt: 3.7
    Helsinki: 6.7
    
    Copollutant: N02, CO
    PM Increment: 10 pg/m
    
    Effect Estimate: SDNN
    0.69ms (95% Cl:-1.24,  2.63)
    HF:2.9%(95%CI:-7.3, 13.1)
    LFHFR:-3.3 (95% Cl:-12.7, 6.1)
    
    Notes: Followed for 6 mo with biweekly
    clinic visits
    
    2-day lag. ULTRA Study
    December 2009
                                     E-20
    

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                  Study
                                              Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Period of Study:
    12-wk period b/t Sep 2003-Jul 2004
    
    Location: Chapel Hill, NC
    Reference: Yeatts et al. (2007, 0912661 Outcome: Heart Rate Variability
    
                                       Age Groups: 21-50 yr
    
                                       Study Design: Panel
    
                                       N: 12 asthmatics
    
                                       Statistical Analyses: Linear Mixed
                                       Model
    
                                       Covariates: Temperature, humidity,
                                       pressure
    
                                       Dose-response Investigated? No
    
                                       Statistical Package: SAS
    
                                       Lags Considered: 1 day
    Pollutant: PM10.2.5
    
    Averaging Time: 24 h
    
    Mean (SD): 5.3 (2.8)
    
    Min:0
    
    Max: 14.6
    
    Monitoring Stations: 1
    
    Copollutant: PM25, PM10
    
    Co-pollutant Correlation:
    PM25 = 0.46*
    PM10 =  NR
    
    *p < 0.01
    PM Increment: 1 pg/m .
    
    Beta, SE (Lower Cl, Upper Cl), p-
    value
    
    HRV
    Max Heart Rate:-1.95, 0.88 (-3.67, -
    0.23), 0.03
    ASDNN5: -0.77, 0.37 (-1.580, -0.04),
    0.05
    SDANN5:-3.76, 1.53 (-6.76, -0.76),
    0.02
    SDNN24HR(mesc): -3.36, 1.38 (-6.06, -
    0.65), 0.02
    rMSSD:-0.75, 0.53 (-1.79, 0.28), 0.16
    pNN50_24hr: -0.50, 0.27 (-1.03, 0.03),
    0.07
    pNN50_7min: -1.88, 0.55 (-2.95, -0.81),
    0.07
    Low-frequency power: -0.19, 0.42 (-
    1.01, 0.63), 0.65
    Percent low frequency: 0.57,1.08 (-
    1.55, 2.69), 0.60
    High-frequency power: -0.46, 0.17 (-
    0.79,-0.14), 0.01
    Percent high frequency: -2.14, 0.94 (-
    3.98, -0.30), 0.03
    
    Blood Lipids
    Triglycerides: 4.78, 2.02(0.81,8.74),
    0.02
    VLDL: 1.15, 0.44 (0.29, 2.02), 0.01
    Total cholesterol: 0.78, 0.54 (-0.28,
    1.84), 0.15
    
    Hematologic Factors
    Circulating eosinophils: 0.16, 0.06
    (0.04, 0.28), 0.01
    Platelets:-1.71,1.11 (-3.89, 0.47), 0.13
    
    Circulating Proteins
    Plasminogen: -0.01, 0.01 (-0.02, 0.00),
    0.08
    Fibrenogen: -0.04, 0.02 (-0.08, 0.00),
    0.07
    Von Willibrand factor: -1.23, 0.66 (-2.53,
    0.06), 0.07
    Factor VII:-0.90, 0.85 (-2.58, 0.77),
    0.29
    1AII units expressed in ug/m3 unless otherwise specified.
    Table E-3.      Short-term exposure - cardiovascular morbidity studies: PIVhs (including PM
                       components/sources).
                Reference
                                               Design & Methods
              Concentrations1
          Effect Estimates (95% Cl)
    Reference: Adar et al. (2007, 0014581
    
    Period of Study: Mar-Jun 2002
    
    Location: St. Louis,  Missouri
                                        Outcome: Heart rate variability: heart
                                        rate, standard deviation of all normal-to-
                                        normal intervals (SDNN), square root of
                                        the mean squared difference between
                                        adjacent normal-to-normal intervals
                                        (rMSSD), percentage of adjacent
                                        normal-to-normal intervals that differed
                                        by more than 50 ms (pNNSO), high
                                        frequency power (HF in the  range of
                                        0.15-0.4Hz), low frequency  power (LF, in
                                        the range of 0.04-0.15Hz), and the ratio
                                        ofLF/HF
    
                                        Age Groups: > 60 yr
    
                                        Study Design: Panel (4 planned
                                        repeated measures surrounding bus
     Pollutant: PM25 (fjg/nf)
    
     Averaging Time: Measurements
     collected over 48 h period surrounding
     the bus trip (during which health
     endpoints were measured) used to
     calculate 5-, 30-, 60-min, 4-h, 24-h ma
    
     Median  (IQR):
     All: 7.7 (6.8)
     Facility:  6.8 (5.1)
     Bus: 17.2 (10.3)
     Activity:  8.2 (16.1)
     Lunch: 11.2 (5.9)
    
     Monitoring Stations: 2 portable carts
    
     Copollutant:	
      PM Increment: IQR
    
      Effect Estimate [Lower Cl, Upper Cl]:
      % change (95%CI) in HRV per IQR in
      the 24-h ma of the microenvironmental
      pollutant (IQr = 4.5 pg/m )
    
      Single-pollutant models:
      SDNN: -5.5 (-6.3, -4.8)
      rMSSD:-9.1 (-9.8,-8.4)
      pNN50+1:-12.2 (-13.3, -11.1). LF: -
      10.8 (-12.3,-9.3)
      HF:-15.1 (-16.7,-13.7)
      LF/HF:5.1(3.9, 6.4)
      H: 1.0 (0.9, 1.2)
    
      Two-pollutant models (with particle
    December 2009
                                                                       E-21
    

    -------
                Reference
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                         trips with a total of 158 person-trips, 35
                                         participating in all 4 trips)
    
                                         N: 44 participants
    
                                         Statistical Analyses: Generalized
                                         additive models
    
                                         Covariates: Subject, weekday, time,
                                         apparent temperature, trip type, activity,
                                         medications, and autoregressive terms
    
                                         Season: Limited data collection period
    
                                         Dose-response Investigated? No
    
                                         Statistical Package: SASv8.02, R
                                         V2.0.1
                                  PM25
                                  BC
                                  Fine particle counts
                                  coarse particle counts
    
                                  Correlation notes: 24-h mean PM25,
                                  BC, and fine particle count concentra-
                                  tions ranged from 0.80-0.98
    
                                  r = 0.76-0.97 when limited to time spent
                                  on the bus
    
                                  r = 0.55-0.86 when comparing bus
                                  concentrations to 24-h ma
    
                                  r = -0.003-0.51 when comparing 5-min
                                  avg and 24-h ma
    
                                  Poor correlations found between coarse
                                  particle count concentrations and all fine
                                  particulate measures during all times
                                  periods
                                 number count coarse):
                                 SDNN: -5.7 (-6.5, -4.9)
                                 rMSSD:-9.4(-10.1,-8.6)
                                 pNN50+1:-13.1(-14.3,-11.9).
                                 LF:-10.7(-12.4,-9.1)
                                 HF: -14.9(-16.5, -13.3); LF/HF: 4.9 (3.6,
                                 6.2)'H: 0.9 (0.7,1.1)
    
                                 Independent short- and medium-term
                                 associations with  HRV across all time
                                 periods
    
                                 % change per IQR (95%CI)
                                 IQR 5-min means = 6.8 pg/m3 and 23:
                                 55-hmeans = 4.2|jg/m3
                                 SDNN: 5-min mean:-0.5 (-0.8,-0.1)
                                 23: 55-h mean: -4.6 (-5.3, -4.0)
                                 rMSSD: 5-min mean: -0.9 (-1.3, -0.5)
                                 23: 55-h mean:-7.5 (-8.1 to-6.8)
                                 pNNSO + 1
                                 5-min mean:-1.1  (-1.7 to-0.5)
                                 23: 55-h mean:-9.9 (-10.9 to-8.9). LF
                                 5-min mean: 0.4 (-0.5,1.2)
                                 23: 55-h mean:-10.0 (-11.4 to-8.6)
                                 HF
                                 5-min mean:-1.5  (-2.3 to-0.6)
                                 23: 55-h mean:-12.9 (-14.2 to-11.5)
                                 LF/HF
                                 5-min mean: 1.9(1.3, 2.4)
                                 23: 55-h mean: 3.2 (2.1, 4.3)
                                 H: 5-min mean: 0.1 (0.1,0.2)
                                 23: 55-h mean: 0.8 (0.7, 0.9)
                                 Independent associations of short-term
                                 avg (5-min means) of PM with HRV by
                                 bus and nonbus periods
    
                                 IQR for bus =  10|jg/m3)and
                                 nonbus = 5.6 pg/m )
    
                                 % change (95%CI)
                                 p-value of interaction
                                 SDNN
                                 Bus:-5.0 (-6.3 to-3.7)
                                 Nonbus:-0.5 (-0.9 to-0.2)
                                 p-value for interaction: O.0001. rMSSD
                                 Bus:-4.8 (-6.2 to-3.5)
                                 Nonbus: -0.7 (-1.1 to -0.4. p-value for
                                 interaction: <0.0001
                                 pNNSO + 1
                                 Bus:-6.3 (-8.4 to-4.2)
                                 Nonbus:-0.8 (-1.4 to-0.3)
                                 p-value for interaction: <0.0001
                                 LF: Bus: -7.0 (-9.8 to -4.1) Nonbus: 0.6
                                 (-0.1, 1.4)
                                 p-value for interaction: O.0001. HF:
                                 Bus: -10.7 (-13.5to -7.9)' Nonbus: -0.7
                                 (-1.5, 0.04) p-value for interaction:
                                 O.0001. LF/HF: Bus: 3.9 (1.7, 6.0)
                                 Nonbus: 1.4 (0.8,1.9)
                                 p-value for interaction: 0.39. H: Bus: 0.7
                                 (0.5,1.0)
                                 Nonbus:-0.01 (-0.08,0.1)
                                 p-value for interaction: <0.0001
                                 Note: Exposure to health associations
                                 by all lag periods presented in Fig 2
                                 (magnitude of associations increased
                                 with averaging period, with the largest
                                 associations consistently found for 24-h
    December 2009
                             E-22
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Adar et al. (2007, 0014581
    
    Period of Study: Mar-Jun 2002
    
    Location: St. Louis, Missouri
    Outcome: Heart rate variability: heart
    rate, standard deviation of all normal-to-
    normal intervals (SDNN), square root of
    the mean squared difference between
    adjacent normal-to-normal intervals
    (rMSSD), percentage of adjacent
    normal-to-normal intervals that differed
    by more than 50 ms (pNNSO), high
    frequency power (HF
    
    intherangeofO.15-0.4Hz), low
    frequency power (LF, in the range of
    0.04-0.15Hz),  and the ratio of LF/HF
    
    Age Groups:  2 60 yr
    
    Study Design: Panel (4 planned
    repeated  measures with a total of 158
    person-trips
    
    35 participating in all 4  trips)
    
    N: 44 participants
    
    Statistical Analyses: Generalized
    additive models
    
    Covariates: Subject, weekday, time,
    apparent temperature, trip type, activity,
    medications, and autoregressive terms
    
    Season: Limited data collection period
    
    Dose-response Investigated? No
    
    Statistical Package: SASv8.02, R
    V2.0.1
    Pollutant: BC (ng/rri)
    
    Averaging Time: Measurements
    collected over 48 h period surrounding
    the bus trip (during which health
    endpoints were measured) used to
    calculate 5-, 30-, 60-min, 4-h, 24-h ma
    
    Median  (IQR): All: 330 (337)
    Facility:  285 (270)
    Bus: 2911(2464)
    Activity:  482 (1168)
    Lunch: 434 (276)
    
    Monitoring Stations: 2 portable carts
    
    Copollutant: PM25
    BC
    Fine particle counts
    Coarse particle counts
    
    Correlation notes: 24-h mean PM25,
    BC, and fine particle count
    concentrations ranged from 0.80 to 0.98
    
    r = 0.76  to 0.97 when limited to time
    spent on the bus
    
    r = 0.55  to 0.86 when comparing bus
    concentrations to 24-h ma
    
    r = -0.003 to 0.51 when comparing 5-min
    avg and 24-h ma
    
    Poor correlations found between coarse
    particle count concentrations and all fine
    particulate measures during all times
    periods
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change (95%CI)  in HRV per IQR in
    the 24-h ma of the microenvironmental
    pollutant (IQr = 459 ng/m3)
    
    Single-pollutant models
    SDNN:-5.3 (-6.5 to-4.1)
    rMSSD:-10.7 (-11.9 to-9.5)
    pNN50+1:-13.2 (-15.0 to-11.4)
    LF:-11.3(-13.7to-8.8)
    HF: -18.8 (-21.1 to-16.5)
    LF/HF: 9.3 (7.2, 11.4)
    
    H: 1.0 (0.8, 1.3)
    
    Independent short-  and medium-term
    associations with  HRV  across all time
    periods
    % change per IQR (95%CI)
    
    IQR 5-min means = 337 ng/m3 and 23:
    55-h means = 490 ng/m3)
    SDNN: 5-min mean: -0.3 (-O.Sto -0.1)
    23:  55-h mean:-4.7 (-5.9 to-3.5)
    rMSSD: 5-min mean: -0.3 (-O.Sto -0.1)
    23:  55-h mean:-9.3 (-10.5 to-8.1)
    pNN50+  1: 5-min mean:-0.3 (-0.6 to -
    0.1)
    23:  55-h mean:-10.5 (-12.3 to-8.7)
    LF:  5-min mean: -0.5 (-0.9 to -0.1)
    23:  55-h mean:-9.8 (-12.4 to-7.2)
    HF: 5-min mean: -0.9 (-1.2 to -0.5)
    23:  55-h mean:-15.4 (-17.8 to-12.9)
    LF/HF: 5-min mean: 0.3 (0.1, 0.6)
    23:  55-h mean: 6.5  (4.5, 8.6)
    H: 5-min mean: 0.1  (0.1, 0.2)
    23:  55-h mean: 0.4  (0.2, 0.7)
    Independent associations of short-term
    avg (5-min means) of PM with HRV by
    bus and nonbus periods
    
    IQR for bus = 2.6 pg/m3) and
    nonbus = 0.27 pg/m )
    
    % change (95%CI)
    p-value of interaction
    SDNN: Bus: -4.6 (-6.1 to -3.0)'  Nonbus: -
    0.1  (-0.3,0.1)
    p-value for interaction:  <0.0001
    rMSSD: Bus: -2.6 (-4.2 to -0.9): Nonbus:
    -0.3 (-0.5 to-0.1)
    p-value for interaction: 0.64
    pNN50+1:Bus:-2.0(-4.5, 0.5):
    Nonbus:-0.5 (-0.8 to-0.1)
    p-value for interaction: 0.34
    LF: Bus: -6.0 (-9.3 to -2.5): Nonbus: -0.2
    (-0.7, 0.3)
    p-value for interaction: 0.028
    HF: Bus:  -5.8 (-9.1 to-2.3)
    Nonbus:-0.9 (-1.4 to-0.4)
    p-value for interaction: 0.50
    LF/HF: Bus:-0.8 (-3.1,  1.7)
    Nonbus: 0.8 (0.5,1.1)
    p-value for interaction:  <0.0001
    H: Bus:-0.5 (-0.8 to-0.2)
    Nonbus: 0.3 (0.26, 0.34)
    p-value for interaction:  <0.0001
    Note: Exposure to health associations
    by all lag  periods presented in Fig 2
    (magnitude of associations increased
    with averaging period, with the largest
    associations consistently found for 24-h
    ma)
    Reference: Auchincloss et al.
    1562341
    Outcome: Blood pressure: Systolic      Pollutant: PM25
    (SBP), diastolic (DBP), mean arterial
                                         PM Increment: 10 pg/m (approx.
                                         equivalent to difference between 90th
    December 2009
                                     E-23
    

    -------
                 Reference
            Design & Methods
             Concentrations1
                            Effect Estimates (95% Cl)
    Period of Study: Jul 2000-Aug 2002      Pulse Pressure 
    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                Note: Supplementary material available
                                                                                                                on-line shows results for DBP and MAP,
                                                                                                                among others
    Reference: Baccarelli et al. (2009,
    1881831
    
    Period of Study: Nov 2000-Jun 2005
    
    Location: Boston, Mass
    Outcome: Heart rate variability
    
    Age Groups: Elderly
    
    Study Design: Panel
    
    N:549 men
    
    Statistical Analyses: Mixed-effects
    model
    
    Covariates: Age, past/current CHD,
    BMI, mean arterial pressure, fasting
    blood glucose, smoking, alcohol
    consumption, use of beta-blockers, CA
    channel blockers, angiotensin-
    converting enzyme inhibitors, room
    temperature, season, apparent
    temperature
    
    Season: No
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    Pollutant: PM25
    
    Averaging Time: 48-h ma
    
    Geometric Mean (96%CI):
    All Visits: 10.5 (10.0,10.9)
    Visits w/Genotype Data: 10.4(9.9,11.0)
    Visits w/o Genotype Data: 10.5 (9.8,
    11.4)
    
    Monitoring Stations: 1
    
    Copollutant: NR
    
    Correlation:  N/A
    PM Increment: 10 pg/m
    
    Percent Change [Lower Cl, Upper Cl],
    P:
    
    All Subjects w/ Genotype Data
    SDNN:-6.0 (-13.5, 2.0), 0.14
    HF:-17.1 (-32.3, 1.6), 0.07
    LF:-8.2 (-22.1, 8.2), 0.31
    
    All Subjects
    SDNN:-7.1 (-13.2, -0.6), 0.03
    HF:-18.7 (-31.1,-4.0), 0.01
    LF:-11.8 (-23.2, -1.3), 0.08
    December 2009
                                    E-25
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Barclay et al. (2007,
    1922291
    
    Period of Study: Jan 2003-May 2005
    
    Location: Aberdeen, Scotland
    Outcome: Haematological outcomes,
    Heart Rhythm outcomes, & Heart Rate
    Variability outcomes
    
    Age Groups: 70.4 (8.9)
    
    Study Design: Panel
    
    N: 132 patients w/ chronic heart failure
    
    Statistical Analyses: Linear & Mixed
    Effects Regression Model
    
    Covariates: Age, temperature, humidity,
    pressure
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: Lags 0-2 day
    Pollutant: PM25
    
    Averaging Time: Daily
    
    Mean: 7.454
    
    Min: 1.092
    
    Max: 21.97
    
    Monitoring Stations: 0
    
    Copollutant: PM10, PNC, N02
    
    Co-pollutant Correlation
    N02 city: 0.164
    NO city: 0.048
    PM,o city: 0.476*
    N02 personal: 0.169
    PNC DEOM: 0.115
    PM25 traffic: 0.522*
    PNC total: 0.367*
    PNC traffic: 0.234
    
    'correlations based on 3-day avg
    concentrations
    
    Notes: PM25 values model predicted
    PM Increment: NR
    
    Beta (Lower Cl, Upper Cl):
    Haemoglobin: -0.509 (-1.560, 0.542)
    Mean corpuscular haemoglobin: 0.188 (-
    0.481,0.857)
    Platelets: 3.022 (0.403, 5.642)
    Haematocrit:-0.813 (-1.892, 0.267)
    White blood cells: -1.652 (-4.727,1.424)
    C reactive protein: 4.924 (-13.022,
    22.869)
    IL-6:-5.980 (-23.649, 11.690)
    von Willebrand factor: 1.363 (-6.561,
    9.287)
    E-selectin: 2.136 (-2.946, 7.217)
    Fibrinogen: -5.579 (-10.403, -0.755)*
    Factor VII: 3.747 (-1.959, 9.452)
    day-dimer: 5.211 (-2.974,13.397)
    All arrhythmias: -7.082 (-28.789,14.626)
    
    Ventricular ectopic beats: -12.203 (-
    39.021, 14.615)
    
    Ventricular couplets: -1.255 (-25.678,
    23.168)
    
    Ventricular runs: -2.548 (-17.448,
    12.351)
    
    Supraventricular ectopic beats:  4.898 (-
    19.772, 29.568)
    
    Supraventricular couplets: 6.138 (-
    16.242, 28.518)
    
    Supraventricular runs: -0.545 (-17.577,
    16.487)
    
    Avg HR: 0.617 (-0.782, 2.016)
    24 hSDNN: 3.645 (-0.227, 7.517)
    24 h SDANN: 4.437 (0.030, 8.844)*
    24 hRMSSD: 0.617 (-0.782, 2.016)
    24 h PNN 50%: 11.247 (-6.228, 28.722)
    24 hLF power: 4.439 (-6.823, 15.701)
    24 hLF normalized:-5.659 (-11.815,
    0.497)
    24 h HF power: 3.800 (-10.863, 18.464)
    24 h HF normalized: -6.597 (-13.724,
    0.531)
    24 hLF/HF ratio: 1.033 (-8.355, 10.414)
    
    *p < 0.05
    
    Notes: Estimates also available for
    PM25 traffic
    
    LF= low frequency
    HF= high frequency
    Reference: Briet et al. (2007, 0930491
    
    Period of Study: NR
    
    Location: Paris, France
    Outcome: Endothelial Function
    
    Age Groups: 20-40 yr
    
    Study Design: Panel
    
    N: 40 white male nonsmokers
    
    Statistical Analyses: Multiple Robust
    Regrssion
    
    Covariates: R53R/R53H genotype, diet,
    subject factor, visit, temperature
    
    Dose-response Investigated? No
    
    Statistical Package: NCSS
    
    Lags Considered: 0-5 days
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    6 day Mean (SD): 28 (6)
    
    Monitoring Stations: NR
    
    Co-pollutant: PM10, S02, NO, N02, CO
    
    Co-pollutant Correlation: N/A
    PM Increment: 1 SD
    
    Beta (Lower Cl, Upper Cl), P, R2:
    Flow-mediated brachial artery dilation:
    -0.32 (-1.10, 0.46), NS, 0.04
    
    Reactive hyperemia:
    15.68(7.11,23.30), O.0001, 0.24
    
    Changes in Endothelial function b/t
    visits:
    1.98(0.67, 3.259), 0.004, 0.44
    December 2009
                                    E-26
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Cardenas et al. (2008,
    1919001
    Period of Study: NR
    Location: Mexico City, Mexico
    Outcome: Heart Rate Variability
    Age Groups: 20-40 yr
    Study Design: Panel
    N: 54 subjects
    Statistical Analyses: Linear GEE
    Pollutant: PM25
    Averaging Time: NR
    26th, 60th, 76th percentile:
    Indoor: 14.8, 28.3, 47.9
    Outdoor: 6.4, 10.8, 16.8
    PM Increment: NR
    Mean Difference (Lower Cl, Upper Cl),
    lag:
    Ln low frequency
    Indoors: -0.028 (-0.0423, -0.0138)
    Outdoors: -0.194 (-0.4509, 0.0627)
                                         models
    
                                         Covariates: Localization, supine
                                         position, gender, age, humidity, heart
                                         rate, orthostatic position, head-up tilt test
                                         result
    
                                         Dose-response Investigated? No
    
                                         Statistical Package: NR
    
                                         Lags Considered: NR
                                         Co-pollutant: NR
    
                                         Co-pollutant Correlation: N/A
                                         Ln high frequency
                                         Indoors:-0.019 (-0.0338,-0.0044)
                                         Outdoors: -0.298 (-0.5553, -0.0401)
    
                                         Ln LF/HF ratio
                                         Indoors:-0.017 (-0.0330,-0.0007)
                                         Outdoors: -0.278 (-0.5540, 0.0030)
    Reference: Cavallari et al. (2007,
    1574251
    Period of Study: 1999-2006
    
    Location: Massachusetts
    Outcome: Heart Rate Variability
    
    Age Groups: 22-63
    
    Study Design: Panel
    
    N: 36 males
    
    Statistical Analyses: Mixed Effects
    Regression Model
    
    Covariates: Age, smoking,  heart rate at
    work
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: Lags 0-14 h
    Pollutant: PM25
    
    Averaging Time: Hourly
    
    Mean (SD): 1.12 (0.76)
    
    Min:0.12
    
    Max: 3.99
    
    Monitoring Stations: NR
    
    Copollutant: NR
    
    Co-pollutant Correlation: N/A
    PM 1 mg Increment: m
    
    Beta (Lower Cl, Upper Cl):
    
    Model 1
    Lag1 h:-1.44 (-7.75, 4.87)
    Lag 2 h:-5.33 (-10.97, 0.31)*
    Lag 3 h:-6.86 (-11.91,-1.81)}
    Lag 4 h:-2.17 (-9.33, 4.99)
    Lag 5 h:-4.73 (-11.99, 2.53)
    Lag 6 h: -3.52 (-9.89, 2.84)
    Lag 7 h:-1.59 (-7.53, 4.35)
    Lag 8 h: -0.72 (-7.63, 6.20)
    Lag 9 h:-5.55 (-10.65,-0.45)}
    Lag 10 h:-3.66 (-8.85, 1.53)
    Lag 11 h:-8.60 (-17.45, 0.24)*
    Lag 12 h:-5.98 (-14.67, 2.70)
    Lag 13 h:-8.27 (-17.00, 0.46)*
    Lag 14 h:-4.19 (-12.71, 4.33)
    
    Model 2
    Lag1 h: 4.10 (-0.39, 8.60)*
    Lag 2 h:-3.21, (-8.78, 2.37)
    Lag 3 h:-6.45 (-11.59, -1.31)}:
    Lag 4 h: -0.01 (-6.96, 6.94)
    Lag 5 h: -2.03 (-8.27, 4.22)
    Lag 6 h:-1.99 (-8.46, 4.48)
    Lag 7 h: -0.34 (-6.22, 5.54)
    Lag 8 h: 0.72 (-6.35, 7.78)
    Lag 9 h:-5.26 (-10.62, 0.11)*
    Lag 10 h:-3.68 (-9.17,1.80)
    Lag 11 h:-9.41 (-18.60,-0.23)}
    Lag 12 h:-6.45 (-15.62, 2.72)
                                                                                                                   Lag 13 h:-7.33
                                                                                                                   Lag 14 h:-4.75
                                                                                             -16.55, 1.8
                                                                                             -13.81, 4.32
                                                                                                                   *p<0.05, }p<0.10
    
                                                                                                                   Notes: Model 1 adjusted for smoking
                                                                                                                   status and age only. Model 2 adjusted
                                                                                                                   for smoking status, age, and heart rate
                                                                                                                   during work.
    December 2009
                                     E-27
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chahine et al. (2007,
    1563271
    
    Period of Study: Jan 2000-Jun 2005
    
    Location: Boston, MA
    Outcome: Heart Rate Variability
    
    Age Groups: Mean 72.8(6.6) yr
    
    Study Design: Panel
    
    N: 539 white males
    
    Statistical Analyses: Mixed Effects
    Model
    
    Covariates: Age, BMI, mean arterial
    pressure, fasting blood glucose,
    smoking, alcohol consumption, use of
    beta-blockers, calcium channel blockers,
    ACE inhibitors,  room temperature,
    season,  outdoor temperature
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 0- to 2-day ma
    Pollutant: PM25
    
    Averaging Time: 1 h
    
    Mean (SD): 11.7 (7.8)
    
    Monitoring Stations: 1
    
    Copollutant: PM10
    
    Co-pollutant Correlation: N/A
    PM Increment: 10 pg/m
    
    Percent Change (Lower Cl, Upper Cl),
    p-value:
    
    loglOSDNN
    Total:-6.8 (-12.9, -0.2), 0.0436
    GSTM1 wildtype: -2.0 (-11.3, 8.3),
    0.6908
    GSTM1 null:-10.5 (-18.2, -2.2), 0.0150
    HMOX-1 <25 repeats: 7.4 (-8.7, 26.2),
    0.3891
    HMOX-1 >25 repeats: -8.5 (-14.8, -1.8),
    0.0137
    
    loglOHF
    Total:-17.3 (-30.0, -2.3), 0.0263
    GSTM1 wildtype: -4.0 (-24.8, 22.6),
    0.7442
    GSTM1 null:-24.2 (-39.2, -5.5), 0.0139
    HMOX-1 <25 repeats: 8.9 (-27.1, 62.8),
    0.6759
    HMOX-1 >25 repeats: -20.1 (-32.9, -5.0),
    0.0115
    
    loglOLF
    Total:-11.2 (-22.8, 2.2), 0.0986
    GSTM1 wildtype:-0.6 (-19.0, 22.0),
    0.9545
    GSTM1 null: -17.0 (-31.0, -0.2), 0.0478
    HMOX-1 <25 repeats: 14.0 (-18.6,  59.5),
    0.4465
    HMOX-1 >25 repeats: -14.0 (-25.7, -0.5),
    0.0430
    Reference: Chen and Schwartz (2008,
    1901061
    
    Period of Study: 1989-1991
    
    Location: U.S.
    Outcome: White Blood Cell count
    
    Age Groups: 20-89 yr
    
    Study Design: Panel
    
    N: 2,978 participants
    
    Statistical Analyses: Mixed Effects
    Models
    
    Covariates: Age, sex, race, SES,
    smoking, alcohol consumption, MS
    abnormalities, indoor air pollutants,
    exercise
    
    Dose-response Investigated? No
    
    Statistical Package: Stata
    
    Lags Considered: NR
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD): 36.8 (13.0) Median(range)
    for
    01:23.1(14.6-27.8)
    PM Increment: Quartile, lyravg (36.8
    pg/m3)
    
    Avg WBC count(SE) by PM quartile:
    01:6760
             79
                                                                            02:31.2
                                                                            03: 38.8
             27.9-34.3
             34.3-43.3
                                                                            04: 53.7 (43.3-78.5)
    
                                                                            Monitoring Stations: NR
    
                                                                            Copollutant: NR
    
                                                                            Co-pollutant Correlation: N/A
    02:6942
    03:
    04:7109(61)
    
    Beta(Lower Cl, Upper Cl), p-value:
    Crude: 239 (58, 420), 0.01
    Model 1:145 (10, 281), 0.035
    Model 2:141 (6,  277), 0.041
    Model 3:138 (2,  273), 0.046
    
    Model 1: Age, sex, race, SES, smoking,
    alcohol consumption, MS abnormalities.
    Model 2: Model 1 plus indoor air
    pollutants, exercise.  Model 3: Clean
    areas (01) vs.. other more polluted
    areas
    December 2009
                                    E-28
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chuang et al. (Chuang et
    al, 2007, 0910631
    
    Period of Study: Between Apr-Jun
    2004 or 2005
    
    Location: Taipei, Taiwan
    Outcome: High-sensitivity C-reactive
    protein (hs-CRP)
    
    Fibrinogen, plasminogen activator
    fibrinogen inhibitor-1 (PAI-1), tissue-type
    plasminogen activator (tPA), 8-hydroxy-
    2'-deoxyguanosine (8-OHdG), and log-
    transformed HRV indices
    (SDNN = standard deviation of NN
    intervals, r-MSSD = square root of the
    mean of the sum of the squares of
    differences between adjacent NN
    intervals, LF = low frequency [0.04-
    0.15Hz], and HF = high frequency[0.15-
    0.40HZ])
    Pollutant: PMi0, nitrate, sulfate
    
    Averaging Time: Hourly data used to
    calculate avg over 1- to 3-day periods
    
    Mean (SD):
    1-day avg: 31.8 (10.6)
    2-day avg: 36.4 (12.6)
    3-day avg: 36.5 (12.6)
    
    Range (Min, Max):
    1-day avg: 16.2, 50.1
    2-day avg: 15.0,53.4
    3-day avg: 12.7,59.5
    
    Monitoring Stations: 2 sites (each
    pollutant measured at 1 site only)
    PMis Increment: IQR
    (1-day avg: 20.4
    2-day avg: 25.2
    3-day avg: 20.0)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change in health endpoint per
    increase in IQR of PM25 (1-3 day
    averaging period
    single pollutant models)
    
    hs-CRP:
                                                                                                                 1-day: 90.2
                                                                                                                 2-day: 99.1
               -10.2,190.1
               -26.1,224.3
                                                                                                                 3-day: 100.4 (-2.9, 203.7)
    
                                                                                                                 8-OHdG:
    «yc wivupa. iu-^u yi
    Study Design: Panel (cross-sectional) f^°gUtant: ™10
    N: 76 students Nitrate
    OC
    Statistical Analyses: Linear mixed- EC
    effects models N02
    CO
    Covariates: Age, sex, BMI, weekday, S02
    temperature of previous day, relative QS
    humidity
    Season: Only 1 season of data
    collection
    Dose-response Investigated? No
    Statistical Package: NR
    1-day: -5.0 -14.3,4.4)
    2-day: -5.5 -15.6,4.6)
    3-day: -5.6 (-13.8, 2.6)
    PAI-1:
    
    1-day: 20.4 (17.3, 33.5)
    2-day: 16.2 1.9,30.5)
    3-day: 20.0 18.5,31.5)
    tPA:
    
    1-day: 12.0 (-2.4, 26.3)
    2-day: 12.0 -2.9, 26.9);
    3-day: 12.0 -2.7, 26.6)
    Fibrinogen:
    1-day: 2.6 (-2.7, 7.8)
    2-day: 1.5 (-4. 1,7.1)
    3-day: 3.6 (-0.8, 8.1)
    
    
    Heart Rate Variability
    
    SDNN:
    
    1-day: -4.0 (-6.1 to -1.9)
    2-day: -2.5 -4.6 to -0.4)
    3-day: -3.0 -5.0 to -1.1)
    
    r-MSSD:
    
    1-day: -3.0 (-8.7, 2.7)
    2-day: -2.0 (-8.4, 4.4);
    3-day: -3.6 (-8.8, 1.6)
    
    LF:
    
    1 -day: -3.1 (-6.1 to -0.1)
    2-day: -3.2 (-4.6, 0.1);
    3-day: -3.4 (-6.1 to -0.6)
    
    
    
    HF:
    1-day: -3.7 -9.4,2.1
    2-day: -2.1 -8.4,4.3
    
    
    ;
    3-day: -4.0 (-9.3, 1.2)
    December 2009
                                    E-29
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chuang et al. (2007,
    0910631
    
    Period of Study: Between Apr-Jun
    2004 or 2005
    
    Location: Taipei, Taiwan
    Outcome: High-sensitivity C-reactive
    protein (hs-CRP)
    Fibrinogen, plasminogen activator
    fibrinogen inhibitor-1 (PAI-1), tissue-type
    plasminogen activator (tPA), 8-hydroxy-
    2'-deoxyguanosine (8-OHdG), and log-
    transformed HRV indices
    (SDNN = standard deviation of NN
    intervals, r-MSSD = square root of the
    mean of the sum of the squares of
    differences between adjacent NN
    intervals, LF = low frequency [0.04-
    0.15Hz], and HF = high frequency[0.15-
    0.40Hzj)
    
    Age Groups: 18-25 yr
    
    Study Design: Panel (cross-sectional)
    
    N: 76 students
    
    Statistical Analyses: Linear mixed-
    effects models
    
    Covariates: Age, sex, BMI, weekday,
    temperature of previous day, relative
    humidity
    
    Season:  Only 1 season of data
    collection
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Pollutant: Nitrate
    
    Averaging Time: Hourly data used to
    calculate avg over 1-3 day periods
    
    Mean (SD): 1-day avg: 4.5 (2.7)
    2-day avg: 4.7 (2.4
    3-day avg: 4.4 (2.2
    
    Range (Min, Max): 1-day avg: 0.7,10.6
    2-day avg: 0.7, 8.9
    3-day avg: 0.8, 7.5
    
    Monitoring Stations: 2 sites (each
    pollutant measured at 1  site only)
    
    Copollutant: PM10
    Sulfate
    PM25
    OC
    EC
    N02
    CO
    S02
    03
    Nitrate Increment: IQR (1-day avg: 2.5
    2-day avg: 4.0
    3-day avg: 3.4)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change in health endpoint per
    increase in IQR of nitrate (1-3 day
    averaging period
    single pollutant models)
    
    hs-CRP: 1-day:-2.1 (-21.9,17.8)
    2-day:-11.6 (-58.6, 35.5)
    3-day:-18.7 (-69.9, 32.5)
    
    8-OHdG:  1-day: 9.0 (4.0,14.1)
    2-day: 15.1 (5.9, 24.3)
    3-day: 15.0 (4.9, 25.0)
    
    PAI-1:1-day: 4.0 (-2.5,10.4)
    2-day: 11.6 (0.1, 23.1)
    3-day: 16.9 (4.3, 29.4)
    
    tPA: 1-day: 2.0 (-6.2,10.3)
    2-day: 12.9 (-1.6, 27.5)
    3-day: 10.0 (-5.8, 25.8)
    
    Fibrinogen: 1-day: 1.6 (-1.3, 4.5)
    2-day: 1.3 (-3.9, 6.5)
    3-day: 1.0 (-4.6, 6.6)
    
    Heart Rate Variability
    SDNN: 1-day: -1.5 (-2.6 to -0.3)
    2-day:-2.6 (-4.7 to-0.5)
    3-day:-3.0 (-5.3 to-0.7)
    
    r-MSSD: 1-day:-5.5 (-8.7 to-2.2)
                                                                                                                               -14.0to-0.2
                                                                                                                     2-day:-7.1
                                                                                                                     3-day:-8.1
                                                                                                                     LF: 1-day:-1.0(-1.6to-0.5)
                                                                                                                     2-day:-2.0 (-5.6,1.6)
                                                                                                                     3-day:-2.0 (-5.2,1.2)
    
                                                                                                                     HF: 1-day: -2.0 (-5.3,14[potential typo,
                                                                                                                     possibly 1.4])
                                                                                                                     2-day:-4.9 (-10.9, 0.9)
                                                                                                                     3-day:-6.9 (-13.4 to-0.3)
    December 2009
                                     E-30
    

    -------
    Reference
    Reference: Chuang et al. (2007,
    0910631
    Period of Study: Between Apr-Jun
    2004 or 2005
    Location: Taipei, Taiwan
    
    
    Design & Methods Concentrations1 Effect Estimates (95% Cl)
    Outcome: High-sensitivity C-reactive Pollutant: Sulfate
    Sulfate Increment: IQR
    protein (hs-CRP) . (1-day avg: 3.9
    Averaging Time: Hourly data used to 2-dav aver 4 3
    Fibrinogen, plasminogen activator calculate avg over
    fibrinogen inhibitor-1 (PAI-1), tissue-type
    plasminogen activator (tPA), 8-hydroxy- Mean (SD): 1-daY
    2'-deoxyguanosine (8-OHdG), and log- 2-daY av9: 41 (37
    transformed HRV indices 3-daY av9: i9 (3^5
    (SDNN = standard deviation of NN R (Mi .. ,
    intervals, r-MSSD = square root of the ™"8' „ '"' ""'
    1- to 3-day periods 3-day avg: 3.8)
    avg: 4. 1 (3.6) Effect Estimate [Lower Cl, Upper Cl]:
    % change in health endpoint per
    increase in IQR of sulfate (1-3 day
    1 H -CIA mo averaging period
    -, ~ ' ' ' ' single pollutant models)
    mean of the sum of the squares of ^ "^n? 11 *
    differences between adjacent NN 3-day avg. 0.4, 11.5 hs.CRP:
    intervals, LF = low frequency [0.04- Monitoring Stations: 2 sites (each ^ay: °°'° ?,8k i« >\\
    0.15HZJ, and HF = high frequency[0.15- po||utant measured at 1 site only) ^ %} %*• 159.4)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    u.tunzj)
    Copollutant: PIvl-;
    Age Groups: 18-25 yr pM25
    Mitrato
    Study Design: Panel (cross-sectional) QCrale
    N: 76 students EC
    N02
    Statistical Analyses: Linear mixed- CO
    effects models S02
    03
    Covariates: Age, sex, BMI, weekday,
    temperature of previous day, relative
    humidity
    Season: Only 1 season of data
    collection
    Dose-response Investigated? No
    Statistical Package: NR
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    8-OHdG:
    1-day: 1.0 (0.3, 1.3)
    2-day: -0.4 (-5.4, 4.7)
    3-day: -0.3 (-4.3, 3.7)
    PAI-1:
    1-day: 12.0 (5.4, 18.7)
    2-day: 13.3 (6.6, 19.9)
    3-day: 11. 2 (5.7, 16.6)
    tPA:
    1-day: 2.0 (-4.6, 8.7)
    2-day: 3.8 (-2.8, 10.3)
    3-day: 3.0 (-2.3, 8.2)
    Fibrinogen:
    1-day: 2.9 (0.2, 5.5)
    2-day: 2.8 (0.1, 5.5)
    3-day: 2.2 (0.4, 4.7)
    Heart Rate Variability
    SDNN:
    1-day: -3.1 (-4.1 to -2.1)
    2-day: -4.1 -5.2 to -3.1)
    3-day: -2.0 -2.9 to -1.2)
    r-MSSD:
    1-day: -5.0 (-8.0 to -2.0)
    2-day: -6.0 (-8.9 to -2.9)
    3-day: -5.7 (-8.2 to -3.2)
    LF:
    1-day: -3.4 (-4.9 to -1.8)
    2-day: -3.0 (-4.5 to -1.5)
    3-day: -3.0 (-4.3 to -1.7)
    HF:
    1-day: -3.5 -6.5 to -0.4)
    2-day: -3.9 -7.0 to -0.8)
    3-day: -3.0 (-5.5 to -0.5)
    December 2009
    E-31
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chuang et al. (2007,
    0986291
    
    Period of Study: NR
    
    Location: Boston, MA
    Outcome: ST Segment Depression
    
    Age Groups: 43-75 yr
    
    Study Design: Panel
    
    N: 48 coronary artery disease patients
    
    Statistical Analyses: Linear &  Mixed
    Logistic Regression models
    
    Covariates: Participant, day of week,
    order of visit, visit date, hour of  day,
    hourly temperature
    
    Dose-response Investigated? No
    
    Statistical Package: R
    
    Lags Considered: Lags 1-72 h
    Pollutant: PM25
    
    Averaging Time: Hourly
    
    26th, 60th, 76th percentile:
    12-havg: 6.18, 8.91,13.18
    24-havg:  6.38,9.20, 13.31
    
    Max:
    12-havg: 37.13
    24-h avg: 40.38
    
    Monitoring Stations: 1
    
    Co-pollutant: BC, CO, 03, N02, S02
    
    Co-pollutant Correlation
    BC: 0.56
    03: 0.20
    N02: 0.38
    S02: 0.25
    PM Increment: Interquartile Increase
    
    Change (Lower Cl, Upper Cl):
    
    12-hmean
    PM25:-0.022 (-0.032,-0.012)
    PM25+ N02: -0.023 (-0.034, -0.012)
    PM25+S02:-0.009 (-0.02, 0.001)
    PM25+BC:-0.011 (-0.023,0.001)
    
    24-h mean
    PM25:-0.026 (-0.037,-0.015)
    PM25+ N02: -0.017 (-0.029, 0.004)
    PM2 5+S02:-0.014 (-0.025,-0.002)
    PM25+BC:-0.012  (-0.026, 0.003)
    
    Relative Risk (Lower Cl, Upper Cl):
    
    12-h mean
    PM25:1.02 (0.86, 1.21)
    PM25+N02: 0.99 (0.82, 1.21)
    PM25+S02: 0.87 (0.71, 1.05)
    PM25+BC: 0.92 (0.74, 1.14)
    
    24-h mean
    PM25:1.22 (0.99, 1.50)
    PM25+N02:1.00 (0.80, 1.25)
    PM25+S02:1.04(0.83, 1.30)
    PM25+BC: 0.87 (0.65, 1.17)
    
    Mean (Lower Cl, Upper Cl):
    12-h mean
    Myocardial Infarction: -0.042 (-0.057, -
    0.026)
    No Myocardial Infarction: -0.012 (-0.023,
    0.00)
    p-for interaction: 0.002
    Visit!:-0.102 (-0.12,-0.085)
    Visits 2-4: 0.006 (-0.005, 0.017)
    p-for interaction: O.001
    Diabetic:-0.097 (-0.119,-0.074)
    Non-diabetic: -0.009 (-0.019, 0.002)
    p-for interaction: O.001
    Diurnal daytime pattern: -0.032 (-0.043, -
    0.021)
    Diurnal nighttime pattern: -0.006 (-0.018,
    0.006)
    p-for interaction: O.001
    24-h mean
    Myocardial Infarction: -0.027 (-0.043, -
    0.012)
    No Myocardial Infarction: -0.025 (-0.038,
    0.011)
    p-for interaction: 0.787
    Visit!:-0.127 (-0.148,-0.105)
    Visits 2-4: 0.001  (-0.011,0.013)
    p-for interaction: O.001
    Diabetic:-0.118 (-0.144,-0.091)
    Non-diabetic:-0.13 (-0.024,-0.002)
    p-for interaction: O.001
    Diurnal daytime pattern: -0.031 (-0.043, -
    0.020)
    Diurnal nighttime pattern: -0.018 (-0.030,
    -0.005)
    p-for interaction: 0.233
    Notes: The effects of PM on half-h St
    segment levels (Fig 1)
    December 2009
                                     E-32
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Dales et al. (2007,1557431
    
    Period of Study: NR
    
    Location: Ottawa, Canada
    Outcome: Vascular Reactivity
    
    Age Groups: 18-50yr
    
    Study Design: Panel
    
    N: 39 volunteers
    
    Statistical Analyses: Mixed Effects
    Model
    
    Covariates: Temperature, humidity,
    wind speed, time of day testing was
    done, site
    
    Dose-response Investigated? No
    
    Statistical Package: S-PLUS
    
    Lags Considered: NR
    Pollutant: PM25
    
    Averaging Time: 2 h
    
    Mean (SD):
    Downtown: 40 (20)
    Tunney's Pasture: 10 (10)
    p-value 0.000
    
    Monitoring Stations: NR
    
    Copollutant: PM1.0
    
    Co-pollutant Correlation
    N/A
    PM Increment: Interquartile Range
    (27.02 pg/m3)
    
    Beta (SE), p-value:
    Flow mediated vasodilation (%): -0.016
    (0.0072) p=0.03
    Heart Rate (beats/min): 0.081  (0.135)
    p=0.55
    Diastolic blood pressure (mmHg): 0.088
    (0.088) p=0.32
    Systolic blood pressure (mmHg): -0.108
    (0.006) p=0.48
    Reference: de Hartog et al. (2009,
    1919041
    
    Period of Study: 1998-1999
    
    Location:
    Amsterdam, The Netherlands
    Erfurt, Germany
    and Helsinki, Finland
    Outcome: Heart Rate Variability
    
    Age Groups: 50+
    
    Study Design: Panel
    
    N: 122 coronary heart disease patients
    
    Statistical Analyses: Linear Regression
    
    Covariates: Time trend, temperature,
    humidity, pressure
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: Lags 0-3 days
    Pollutant: PM25
    
    Averaging Time: Daily
    
    p26, p60, p76. p96:
    Amsterdam: 10.4,16.7, 23.9, 47.0
    Erfurt: 10.8, 16.3, 26.7, 62.3
    Helsinki: 8.3,10.6,15.9,25.8
    
    Monitoring Stations: NR
    
    Copollutant: PM <0.1, PMO.1-1.0, N02,
    S02
    
    Co-pollutant Correlation
    NR
    
    Note: Correlations are provided for
    source-specific PM25 & elements
    PM Increment: 1 pg/m
    
    Beta (Lower Cl, Upper Cl):
    
    SDNN
    Local traffic:-0.12 (-0.36, 0.12)
    Long-range transport: -0.04 (-0.14, 0.06)
    Oil combustion:-0.29 (-1.04, 0.45)
    Industry: 0.03 (-0.12, 0.19)
    Crustal:0.11  (-0.35,0.56)
    Salt:-0.19 (-1.92, 1.55)
    
    HF
    Local traffic: 0.43 (-0.91,1.79)
    Long-range transport: 0.19 (-0.38, 0.77)
    Oil combustion: 1.05 (-2.70, 4.94)
    Industry: 0.62 (-0.34,1.59)
    Crustal: 1.57 (-1.28, 4.50)
    Salt:-1.43 (-9.86, 7.78)
    
    SDNN
    ABS:-0.52 (-1.39, 0.31)
    S:-0.51 (-1.36, 0.33)
    V:-0.66 (-1.73, 0.41)
    Zn: 0.12 (-0.55, 0.79)
    Ca: 0.27 (-0.58, 1.11)
    Cl: 0.14 (-0.39, 0.67)
    Fe: 0.15 (-1.00,1.30)
    Cu: -0.08 (-0.74, 0.57)
    
    SDNN
    ABS: 2.91 (-2.54, 8.67)
    S:0.25 (-4.42, 5.14)
    V: 0.73 (-4.74, 6.53)
    Zn: 3.85 (-0.26, 8.13)
    Ca: 3.39 (-1.80, 8.86)
    CM.13 (-1.48, 3.81)
    Fe: 6.69 (0.11, 13.69)
    Cu: 3.00 (-0.85, 7.00)
    
    Notes: Estimates provided are for all
    subjects at lag 1,  estimates are also
    available at lags 0, 2, and 3, as well as
    for subjects w/o beta-blockers at lags
    0-3.
    December 2009
                                     E-33
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: DeMeo et al. (2004,
    0873461
    
    Period of Study: Jul-Aug 1999
    
    Location: Boston, MA
    Outcome: Oxygen saturation
    
    Age Groups: 60.4-89.2 yr
    
    Study Design: Cross-sectional study
    
    N: 28 adult participants
    
    Statistical Analyses: GLM, Natural
    Spline Smoothing, Regression Analysis,
    Random-effects model
    
    Covariates:  Mean temperature, Dew
    point temperature, Barometric pressure,
    Medication use
    
    Season: Summer
    
    Dose-response Investigated? No
    
    Statistical Package:
    S-PLUS, SAS
    
    Lags Considered: Hourly lags between
    2 and 7 h
    Pollutant: PM25
    
    Averaging Time: 6 h, 12 h, 24 h, 48 h
    PM Increment: IQR (13.42 pg/rri)
    increase
    6 h: 13.42 pg/m3
    12 h: 10.81 pg/m3
    24h:10.26|jg/m3
    48:10.57 pg/m3
    Overall: 0.172% (-0.313, 0.031)
    decrease
    6 h: -0.769% (-1.21 to -0.327) decrease
    B-blocker users: -0.062% (-0.248, 0.123)
    
    Rest: 6 h:-0.173  (-0.345 to-0.001)
    12 h:-0.160 (-0.308 to-0.012)
    24 h:-0.169 (-0.316 to-0.022)
    48 h:-0.153 (-0.304, 0.002)
    
    Exercise: 6 h:-0.005 (-0.215,  0.205)
    12 h:-0.014 (-0.196, 0.168)
    24 h: 0.001 (-0.180,0.182)
    48 h:-0.011 (-0.196, 0.174)
    
    Post exercise Rest: 6  h: -0.173 (-0.332
    to-0.014)
    12 h:-0.128 (-0.266, 0.010)
    4 h:-0.113 (-0.250, 0.023)
    48 h:-0.157 (-295 to-0.019)
    
    Paced breathing: 6 h:  -0.142 (-0.292,
    0.007)
    12 h:-0.139 (-0.269 to-0.010)
    24 h:-0.121 (-0.248,0.007)
    48 h:-0.082 (0.211, 0.047)
    
    Summary over protocol
    6 h:-0.131 (-0.247 to-0.015)
    12 h:-0.120 (-0.221, 0.020)
    24 h:-0.112 (-0.212 to-0.013)
    Notes: Fig of the variation in oxygen
    saturation during  the first rest period vs..
    individual hourly lag measurements for
    PM25
    Reference: Diez-Roux et al. (2006,
    1564001
    
    Period of Study: Baseline data
    collected Jun 2000-Aug 2002
    
    Location:
    USA
    6 field centers:
    Baltimore, MD
    Chicago, IL
    Forsyth Co, NC
    Los Angeles, CA
    New York, NY
    St. Paul, MN
    Outcome: C-reactive protein (CRP)
    assessed continuously and as a
    dichotomous variable (cutpoint, 3 mg/L)
    
    interleukin-6 (IL-6)
    
    Age Groups: 45-84 yr
    
    Study Design: Cross-sectional
    
    N: 5634 persons
    
    Statistical Analyses: Linear regression
    & logistic regression
    
    Covariates: Age, sex, race/ethnicity,
    general health status, BMI, diabetes,
    cigarette status, secondhand smoke,
    physical activity, arthritis flare in last 2
    wk, medications, infections in last 2 wk
    (also ran models including site,
    copollutants, and weather)
    
    Season: Examined seasonal patterns in
    the residuals of fully adjusted models
    stratified by season
    
    Dose-response Investigated? No
    
    Statistical Package:  NR
    Pollutant: PM25
    
    Averaging Time: Prior day, prior 2 days,
    prior wk, prior 30 days, and prior 60
    days
    
    Mean (SD): Presented in Fig 1 by site
    
    Percentiles: Presented in Fig 1 by site
    
    Range: NR
    
    Monitoring Stations: NR
    
    Long-term exposure to PM estimated
    based on residential history reported
    retrospectively
    
    All addresses geocoded
    
    Ambient AP obtained from U.S. EPA
    
    Copollutant:
    S02
    N02
    CO
    03
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Adjusted (all personal-level covariates)
    relative difference in CRP (mg/L) per
    10 pg/m3 increase in PM25
    
    Prior day: 0.99 (0.96,1.01)
    Prior2 days: 0.99 (0.96,1.01)
    Prior 7 days: 1.00 (0.96,1.04)
    Prior 30 days: 1.03
    Prior 60 days: 1.04
    0.98,1.10)
    0.97,1.11)
    Odds Ratios of CRP of > 3 mg/L per
    10 pg/m3 increase in PM25 (adjusted for
    all personal-level covariates)
    
    Prior day: 0.98 (0.92,1.04)
                                                                                                                    Prior 2 days: 0.99
                                                                                                                    Prior 7 days: 1.05
                     0.93,1.06
                     0.96, 1.15
                                                                                                                    Prior 30 days: 1.12 (0.98,1.29)
                                                                                                                    Prior 60 days: 1.12 (0.96,1.32)
    December 2009
                                     E-34
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Dubowsky et al. (2006,
    0887501
    
    Period of Study: Mar-Jun 2002
    
    Location: St. Louis, Missouri
    Outcome: White blood cells (WBC),
    C-reactive protein (CRP), interleukin-6
    (IL-6)
    
    Age Groups: > 60 yr
    
    Study Design: Panel (4 planned
    repeated measures
    
    n = 35 participated in 4 trips)
    
    N: 44 participants
    
    Statistical Analyses: Linear mixed
    models
                                         Covariates: Sex, obesity, diabetes,
                                         smoking history, time-varying
                                         parameters (apparent temperature, h,
                                         day, trip, residence, mold, pollen, illness,
                                         and juice intake), medication and vitamin  Copollutant:
                                         consumption (day of blood draw)
    Pollutant: PM25 (ambient)
    
    Averaging Time: Hourly data used to
    calculate avg concentrations over 1-7
    days preceding the blood draw (ambient
    PM25)
    
    Microenvironmental PM25 measures
    were avgd over the 1-2 days preceding
    the blood draw
    
    Mean (SD) (1-day): 16 (6.0)
    
    Percentiles (1-day): 0:6.5
    25th: 12
    75th: 22
    100th: 28
                                         Monitoring Stations: 1 ambient monitor
                                         Season: Limited data collection period
    
                                         Dose-response Investigated? No
    
                                         Statistical Package: SAS v8.02
                                         PM25 (ambient)
                                         BC (ambient)
                                         PM25(microenvironment)
                                         CO
                                         N02
                                         S02
                                         03
    PM Increment: 6.1 pg/m (5-day mean)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Note: Most results presented in figures.
    Selected result in abstract text: %
    change in WBC per increase in IQR
    (5.4 fjg/m3) of PM2 5 avgd over the
    previous week: 5.5(0.1,11)
    
    Associations (% changes and 95%CI)
    between 5-day mean ambient
    concentrations and markers of
    inflammation per increase (IQR)  in
    pollutant.
    
    CRP: All participants: 14 (-5.4, 37)
    
    Among those with all 3 conditions
     diabetes, obesity, and hypertension): 81
     21,172)
    
    Among those with at least 2 of the
    conditions: 11 (-7.3, 33)
    
    IL-6: All participants:-2.1 (-13,11)
    
    Among those with all 3 conditions
    (diabetes, obesity, and hypertension): 23
    (-5.3, 59)
    
    Among those with at least 2 of the
    conditions:-3.1 (-14,9.7)
    
    WBC (X109/L): All participants: 3.4 (-1.8,
    8.9)
    
    Among those with all 3 conditions
    (diabetes, obesity, and hypertension):
    0.4 (-8.8,11)
    
    Among those with at least 2 of the
    conditions: 3.6 (-1.7, 9.1)
    Reference: Dubowsky et al. (2006,
    0887501
    Period of Study: Mar-Jun 2002
    
    Location: St. Louis, Missouri
    Outcome: White blood cells (WBC),
    C-reactive protein (CRP), interleukin-6
    (IL-6)
    
    Age Groups: > 60 yr
    
    Study Design: Panel (4 planned
    repeated measures
    
    n = 35 participated in 4 trips)
    
    N: 44 participants
    
    Statistical Analyses: Linear mixed
    models
                                         Covariates: Sex, obesity, diabetes,
                                         smoking history, time-varying
                                         parameters (apparent temperature, h,
                                         day, trip, residence, mold, pollen, illness,
                                         and juice intake), medication and vitamin  Copollutant:
                                         consumption (day of blood draw)
    Pollutant: BC (ng/m3) (ambient)
    
    Averaging Time: Hourly data used to
    calculate avg concentrations over 1-7
    days preceding the blood draw (ambient
    PM)
    
    microenvironmental PM25 measures
    were avgd over the 1-2 days preceding
    the blood draw
    
    Mean (SD) (1-day): 900 (280)
    
    Percentiles (1-day): 0:290
    25th: 730
    75th: 1,100
    100th: 1,400
                                         Monitoring Stations: 1 ambient monitor
                                         Season: Limited data collection period
    
                                         Dose-response Investigated? No
    
                                         Statistical Package: SAS v8.02
                                         PM25 (ambient)
                                         BC (ambient)
                                         PM25(microenvironment)
                                         CO
                                         N02
                                         S02
                                         03
    PM Increment: 230 ng/m  (5-day mean)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Note: Most results presented in figures.
    
    Associations (% changes and 96%CI)
    between 6-day mean ambient
    concentrations and markers of
    inflammation per increase (IQR) in
    pollutant.
    
    CRP: All participants: 13 (-0.34, 28)
    
    Among those with all 3 conditions
    (diabetes, obesity,  and hypertension): 49
    (16, 90)
    
    Among those with at least 2 of the
    conditions: 9.0 (-3.8, 24)
    
    IL-6: All participants: -0.8 (-8.9, 8.0)
    
    Among those with all 3 conditions
     diabetes, obesity,  and hypertension): 15
     -2.2, 35)
    
    Among those with at least 2 of the
    conditions:-2.7 (-11, 6.2)
    
    WBC (X109/L): All participants: 1.3 (-2.1,
    4.8)
    
    Among those with all 3 conditions
    (diabetes, obesity,  and hypertension):
    0.05 (-5.9,  6.3)
    
    Among those with at least 2 of the
    conditions: 1.5 (-2.0, 5.1)
    December 2009
                                     E-35
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ebelt et al. (2005, 0569071
    
    Period of Study: Summer of 1998
    
    Location: Vancouver, Canada
    Outcome: CVD
    
    Age Groups: Range from 54-86 yr
    mean age= 74 yr
    
    Study Design: Extended analysis of a
    repeated-measures panel study
    
    N: 16 persons with COPD
    
    Statistical Analyses: Earlier analysis
    expanded by developing mixed-effect
    regression models and by evaluating
    additional exposure indicators
    
    Dose-response Investigated? No
    
    Statistical Package: SASV8
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD):
    Ambient PM25:11.4 ±4.6
    Exposure to ambient PM2.$. 7.9 ±3.7
    
    Range (Min, Max):
    Ambient PM25: 4.2-28.7
    
    Exposure to ambient PM25: 0.9-21.3
    
    Monitoring Stations: 5
    
    Copollutant (correlation):
    Ambient concentrations and exposure to
    ambient PM were highly correlated for
    each respective metric:  r 2 0.71
    PM Increment:
    
    Increment: C2.5: IQR = 5.8
    SBP (mm Hg):-1.70 (-3.48-0.08)
    DBP (mm Hg): -0.58 (-2.02-0.85)
    Ln-SVE (bph): 0.20 (0.00-0.40)
    HR (bpm): 0.93 (-0.90-2.75)
    SDNN (ms): -4.37 (-9.40-0.65)
    R-MSSD(ms):-2.79 (-6.16-0.57)
    
    Increment: NS_C2.5: IQR = 4.2
    SBP (mm Hg):-1.52 (-2.94--0.09)
    DBP (mm Hg):-0.77 (-1.87-0.32)
    Ln-SVE (bph): 0.19 (-0.01-0.38)
    HR (bpm): 1.03 (-0.43-2.48)
    SDNN (ms):-3.83 (-7.77-0.11)
    R-MSSD(ms):-2.90 (-5.55--0.25)
    
    Increment: S_C2.5: IQR =1.5
    SBP (mm Hg):-1.10 (-3.48-1.28)
    DBP (mm Hg): 0.76 (-1.15-2.68)
    Ln-SVE (bph): 0.09 (-0.05-0.23)
    HR (bpm):-0.42 (-2.28-1.44)
    SDNN (ms):-3.14 (-9.73-3.45)
    R-MSSD(ms): 0.24 (-5.14-5.63)
    
    Increment: A2.5: IQR = 4.4
    SBP (mm Hg):-1.90 (-3.66--0.14)
    DBP (mm Hg):-0.33 (-1.72-1.06)
    Ln-SVE (bph): 0.20 (0.02-0.37)
    HR (bpm): 0.57 (-1.34-2.47)
    SDNN (ms): -3.91 (-8.79-0.97)
    R-MSSD(ms):-1.05 (-4.79-2.17)
    
    Increment: NS_A2.5: IQR = 3.4
    SBP (mm Hg):-1.70 (-3.27--0.14)
    DBP (mm Hg):-0.51 (-1.71-0.70)
    Ln-SVE (bph): 0.20 (0.02-0.37)
    HR (bpm): 0.69 (-0.96-2.35)
    SDNN (ms):-4.18 (-8.51-0.15)
    R-MSSD(ms):-1.40 (-4.40-1.60)
    
    Increment: S_T2.5: IQR = 0.9
    SBP (mm Hg):-1.55 (-3.35-0.26)
    DBP (mm Hg): 0.49 (-0.91-1.90)
    Ln-SVE (bph): 0.08 (-0.14-0.19)
    HR (bpm):-0.24 (-1.75-1.26)
    SDNN (ms): -0.68 (-4.74-3.38)
    R-MSSD (ms): 0.91 (-3.51-5.33)
    
    Increment: T2.5: IQR =10.1
    SBP (mm Hg):-1.26 (-2.60-0.08)
    DBP (mm Hg): 0.34 (-1.26-1.94)
    Ln-SVE (bph): 0.01 (-0.10-0.11)
    HR (bpm):-0.23 (-1.09-0.63)
    SDNN (ms):-2.11 (-4.90-0.68)
    R-MSSD (ms):-0.83 (-3.60-1.94)
    
    Increment: N2.5: IQR = 8.9
    SBP (mm Hg):-0.81 (-2.15-0.53)
    DBP (mm Hg): 0.40 (-1.19-1.98)
    Ln-SVE (bph):-0.04 (-0.18-0.10)
    HR (bpm):-0.35 (-0.85-0.14)
    SDNN (ms):-1.10 (-3.10-0.90)
    R-MSSD (ms):-0.54 (-2.54-1.46)
    
    Note: Total personal fine particle
    exposure (T) were dominated by
    exposures to non ambient particles
    which were not correlated with ambient
    fine particle exposure (A) or ambient
    concentrations (C). Results for each of
    these metrics are listed.
    December 2009
                                    E-36
    

    -------
    Reference Design & Methods
    Reference: Fan et al. (2008, 191979) Outcome: Cardiopulmonary Health
    „ • ., «~ ., ,-,„ ™nr (FEV, FVC, PEF, SDNN, HR)
    Period of Study: Feb-May 2005
    Age Groups: 61.2 (13.7)
    Location: Paterson, New Jersey
    Study Design: Panel
    
    N:11
    Statistical Analyses: Mixed Effects
    models, Linear Regression models
    Covariates: Temperature, humidity
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered :0
    
    
    
    
    
    
    
    
    
    
    Concentrations1
    Pollutant: PM,5
    Averaging Time: Daily
    Mean (SD): |
    
    APM25avg
    Morning: 35.2 (25.9)
    Afternoon: 24.1 (22.1)
    APM25peak
    Morning: 71. 3 (56.1)
    Afternoon: 64.3 (43.5)
    Range:
    APM2.5 avg
    Morning: 1.1 -87
    Afternoon: 1.2-98
    APM25 peak
    Morning: 4.0 -278
    Afternoon: 3.0 -150
    Monitoring Stations: NR
    Copollutant: NR
    Co-pollutant Correlation: N/A
    
    
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    Beta (SE), p-value:
    ASDNN
    Morning, APM25avg
    15mirv-145(69) 006
    2h: -18.9 (4.2), 0.0002
    4h: -2.5 (8.6), 0.78
    Morning, APM25 peak
    15min: -9.2 (112), 0.43
    2h: -5.1 (13.8), 0.72
    4h: -7.4 (12.0), 0.55
    Afternoon, APM25 avg
    15min: -2.4 (7.6), 0.77
    2h: -20.2 (10.8), 0.10
    4h: -0.7 (11. 2), 0.95
    Afternoon, APM25 peak
    15min: 0.6 (8.9), 0.95
    2h: 19.2 (14.6), 0.23
    4h: -6.8 (14.1), 0.64
    AHR
    Morning, APM25avg
    15min: 1.2 (3.1), 0.71
    2h: -5.5 (2.9 , 0.08
    4h: -3.1 (4.6, 0.51
    Morning, APM25peak
    15min: 0.8 (4.4), 0.86
    2h: -7.2 (4.2, 0.11
    4h: -7.1 (6.3, 0.28
                                                                                                                 Afternoon, APM25 avg
                                                                                                                 15min:-2.0 (4.0), 0.62
                                                                                                                 2h: 0.9 (5.4), 0.87
                                                                                                                 4h: 8.2 (5.2), 0.14
    
                                                                                                                 Afternoon, APM25 peak
                                                                                                                 15min:-5.6 (5.3), 0.31
                                                                                                                 2h: 3.1 (8.1), 0.71
                                                                                                                 4h:11.1 (8.1), 0.20
    
                                                                                                                 AFEV,
                                                                                                                 Morning, APM25 avg: 0.02 (0.04), 0.68
                                                                                                                 Morning, APM25 peak: -0.13 (0.08), 0.16
    
                                                                                                                 A FVC
                                                                                                                 Morning, APM25 avg: -0.10 (0.09), 0.31
                                                                                                                 Morning, APM25 peak: -0.12 (0.17), 0.51
    
                                                                                                                 A PEF
                                                                                                                 Morning, APM25 avg: -0.54 (0.62), 0.42
                                                                                                                 Morning, APM25 peak: -1.46 (1.12), 0.24
    
                                                                                                                 Notes: Estimates relative to increases in
                                                                                                                 the avg and peak PM25 concentrations
    Reference: Folino et al. (2009,1919021
    
    Period of Study: Jun 2006-May 2007
    
    Location: Padua, Italy
    Outcome: HRV & Inflammatory Markers
    
    Age Groups: 45-65 yr
    
    Study Design: Panel
    
    N: 39 patients w/ myocardial infarction
    
    Statistical Analyses: Linear Regression
    Model, ANOVA
    
    Covariates: Temperature, relative
    humidity, atmospheric pressure, beta-
    blocker, aspirin, or nitrate consumption,
    smoking habit
    
    Dose-response Investigated? No
    
    Statistical Package: Stata
    
    Lags Considered: NR
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD):
    Summer: 33.9 (12.7)
    Winter: 62.1 (27.9)
    Spring: 30.8 (14.0)
    
    Monitoring Stations: NR
    
    Copollutant: PM10,  PM0.25
    
    Co-pollutant Correlation: NR
    PM Increment: 1 pg/m
    
    Beta (SE), p-value:
    
    SDNN: 0.109 (0.115), 0.345
    SDANN: 0.127 (0.126), 0.314
    RMSSD: 0.045 (0.040), 0.256
    pH: 0.002 (0.001), 0.041
    LTB4: 0.590 (0.324), 0.069
    eNO: -0.002 (0.003), 0.503
    PTX3: -0.004 (0.002), 0.013
    C-reactive protein: -0.008 (0.005), 0.115
    CC16:-0.002 (0.002), 0.410
    IL-8: 0.000 (0.003), 0.989
    December 2009
                                    E-37
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Folino et al. (2009,1919021
    
    Period of Study: Jun 2006-May 2007
    
    Location: Padua, Italy
    Outcome: HRV & Inflammatory Markers
    
    Age Groups: 45-65 yr
    
    Study Design: Panel
    
    N: 39 patients w/ myocardial infarction
    
    Statistical Analyses: Linear Regression
    Model, ANOVA
    
    Covariates: Temperature, relative
    humidity, atmospheric pressure, beta-
    blocker, aspirin, or nitrate consumption,
    smoking habit
    
    Dose-response Investigated? No
    
    Statistical Package: Stata
    
    Lags Considered: NR
    Pollutant: PM025
    
    Averaging Time: 24 h
    
    Mean (SD):
    Summer: 17.6(7.5)
    Winter: 30.5 (17.4)
    Spring: 18.8 (10.8)
    
    Monitoring Stations: NR
    
    Copollutant: PM10, PM25
    
    Co-pollutant Correlation: NR
    PM Increment: 1 pg/m
    
    Beta (SE), p-value:
    
    SDNN: 0.214 (0.204), 0.295
    SDANN: 0.214 (0.214), 0.316
    RMSSD: 0.081 (0.077), 0.291
    pH: 0.005 (0.002), 0.004
    LTB4: 0.835 (0.533), 0.117
    eNO:-0.006 (0.005), 0.182
    PTX3: -0.006 (0.003), 0.071
    C-reactive protein: -0.011  (0.007), 0.104
    CC16: 0.001 (0.004), 0.890
    IL-8: -0.004 (0.006), 0.527
    Reference: Goldberg et al. (2008,
    1803801
    Period of Study: Jul 2002-Oct 2003
    
    Location: Montreal, Canada
    Outcome: Oxygen saturation & pulse
    rate
    
    Age Groups: 50-85 yr
    
    Study Design: Panel
    
    N:31
    
    Statistical Analyses: Mixed Random
    Effects Model
    
    Covariates: Body temperature,
    consumption of salt, intake of fluids,
    being ill the day before, ambient
    temperature, relative humidity,
    barometric pressure
    
    Dose-response Investigated? No
    
    Statistical Package: Splus
    
    Lags Considered: lags 1 day; 0- to
    2-day avg
    Pollutant: PM25
    
    Averaging Time: Daily
    
    IQR: 7.3
    
    Monitoring Stations: 8
    
    Co-pollutant: CO, N02, S02, 03
    
    Co-pollutant Correlation
    CO: 0.72
    N02: 0.62
    PM Increment: Interquartile Range
    (7.3pg/m3)
    
    Mean Difference (Lower Cl, Upper Cl),
    lag:
    
    Oxygen Saturation
    Unadjusted:
    -0.087 (-0.143, -0.031), lag 0
    Unadjusted:
    -0.058 (-0.114, -0.002), lag 1
    Unadjusted:
     -0.083 (-0.155, -0.010), lag 0-2-day avg
    Adjusted: -0.056 (-0.117, 0.005), lag 0
    Adjusted: -0.019 (-0.079, 0.041), lag 1
    Adjusted: -0.039 (-0.118, 0.039), lag 0-
    2-day avg
    
    Pulse Rate
    Unadjusted: 0.226 (-0.037, 0.489), lag 0
    Unadjusted: 0.288 (0.022, 0.554), lag 1
    Unadjusted: 0.420 (0.067, 0.772), lag 0-
    2-day avg
    Adjusted: 0.158 (-0.136, 0.451), lag 0
                                                                                                                 Adjusted: 0.246
                                                                                                                 Adjusted: 0.353
                                                                                                                 2-day avg
                                                                                            -0.040, 0.531), lag 1
                                                                                            -0.034, 0.740), lag 0-
    December 2009
                                    E-38
    

    -------
    Reference
    Reference: Goldberg et al. (2008,
    1803801
    
    Period of Study: Jul 2002-Oct 2003
    Location: Montreal, Canada
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Shortness of Breath &
    General health
    
    Age Groups: 50-85 yr
    Study Design: Panel
    
    N:31
    Statistical Analyses: Mixed Random
    Fffprtc Mnrlpl
    CIICULo IVIUUCI
    Covariates: Body temperature,
    consumption of salt, intake of fluids,
    being ill the day before, ambient
    temperature, relative humidity,
    barometric pressure
    Dose-response Investigated? No
    Statistical Package: Splus
    Lags Considered: lags 0-4 days; 0- to
    2-day avg
    
    
    Concentrations1
    Pollutant: PM25
    
    Averaging Time: Daily
    Mean: 9.5
    
    Median: 7.0
    Mirr D R
    IVIIIK U.u
    Max: 50.2
    
    IQR: 7.3
    Monitoring Stations: 8
    Co-pollutant: CO, N02, S02, 03
    Co-pollutant Correlation
    CO: 0.66
    N02: 0.54
    03: 0.32
    S02: 0.50
    Effect Estimates (95% Cl)
    PM Increment: Interquartile Range
    (7.3 pg/m3)
    
    
    
    Mean Difference (Lower Cl, Upper Cl),
    lag:
    IMV).
    General Health
    
    
    Unadjusted: -0.317 (-0.699, 0.064), lag 0
    Unadjusted: -0.284
    Unadjusted: -0.048
    -0.670, 0.103), lag 1
    -0.427, 0.332), lag 2
    Unadjusted: -0.241 (-0.620, 0.139), lag 3
    Unadjusted: -0.010 (-0.390, 0.370), lag 4
    Unadjusted: -0.482 (-1.053, 0.090), lag
    0-2-day avg
    Adjusted: -0.125 (-0.545, 0.295), lag 0
    Adjusted: -0.167 (-0.568, 0.234 , lag 1
    Adjusted: -0.081 (-0.464, 0.302 , lag 2
    Adjusted: -0.222 (-0.602, 0.157), lag 3
    Adjusted: 0.016 (-0.364, 0.396), lag 4
    Adjusted: -0.281 (-0.886, 0.325), lag
    0-2-day avg
    
    Shortness of breath at night
    
    
    Unadjusted: -0.421
    Unadjusted: -0.278
    -0.847, 0.006), lag 0
    -0.711,0.155), lag 1
    Unadjusted: -0.100 (-0.526, 0.327), lag 2
    
    
    
    
    
    
    Unadjusted: -0.220
    Unadjusted: -0.206
    -0.645, 0.206), lag 3
    -0.632, 0.220), lag 4
    A *-jr\ n n/?o\ i 	
                                                                                                                     Unadjusted: -0.555 (-1.172, 0.063), lag
                                                                                                                     0-2-day avg
                                                                                                                     Adjusted: -0.171 (-0.639, 0.297), lag 0
                                                                                                                     Adjusted: -0.130 (-0.579, 0.319), lag 1
                                                                                                                     Adjusted:-0.127 (-0.553, 0.299
                                                                                                                     Adjusted:-0.192 (-0.616, 0.231
                                                                          Jag 2
                                                                          , Iag3
                                                                                                                     Adjusted: -0.171 (-0.594, 0.253), lag 4
                                                                                                                     Adjusted: -0.301 (-0.952, 0.350), lag
                                                                                                                     0-2-day avg
    Reference: Ibald-Mulli et al. (2004,
    0874151
    
    Period of Study: Winter 1998-1999
    Location:
    Helsinki, Finland
    Erfurt, Germany
    Amsterdam, the Netherlands
    
    
    
    
    Reference: Langrish et al. (2009,
    1919081
    
    Period of Study: Aug 2008
    Location: Beijing, China
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Blood Pressure & Heart Rate
    
    Age Groups: 40-84
    Study Design: Panel
    
    N: 131 adults w/CHD
    Statistical Analyses: Linear Regression
    Covariates: Trend, day of week,
    temperature, barometric pressure,
    relative humidity, medication use
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: 0-2, 5-day avg
    Outcome: Cardiovascular Effects
    
    Age Groups: Median 28 yr
    Study Design: Panel
    N: 15
    Statistical Analyses: NR
    Covariates: NR
    
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: NR
    
    
    
    
    
    
    Pollutant: PM25
    
    Averaging Time: 24 h
    Mean (SD):
    Downtown: 40 (20)
    Tunney's Pasture: 10 (10)
    p-value 0.000
    Monitoring Stations: NR
    Copollutant: PM10
    Co-pollutant Correlation: N/A
    
    
    Pollutant: PM25
    
    Averaging Time: NR
    Mean:
    W/o mask: 86
    W/ mask: 140
    Monitoring Stations: NR
    Co-pollutant: CO, S02, N02
    
    Co-pollutant Correlation: N/A
    
    
    
    
    
    
    
    
    PM Increment: Interquartile Range
    (27.02 pg/m3)
    
    Beta (SE), p-value:
    Flow mediated vasodilation (%):
    -0.016 (0.0072) p=0.03
    Heart Rate (beats/min):
    0.081 (0.135) p=0.55
    Diastolic blood pressure (mmHg):
    0.088 (0.088) p=0.32
    Systolic blood pressure (mmHg):
    -0.108 (0.006) p=0.48
    
    
    
    PM Increment: NR
    
    Mean (Lower Cl, Upper Cl):
    W/o Mask (Day)
    SBP:100(104, 116)
    DBP' 73 (69 76)
    MAP: 85 (81, 88)
    Heart Rate: 79 (74, 84)
    Avg NN interval: 829 (789, 869)
    pNNSO: 15.9 (10.7, 21.0)
    RMSSD:35.1 (29.2,41.0)
    SDNN:61.2(54.9, 67.5)
    Triangular index: 12.9(11.9, 13.9)
    LF power: 81 6 (628, 1004)
    HF power: 460 (325, 595)
    LFn: 62.8 (56.7, 68.9)
    HFn: 29.2 (25.5, 32.8)
    HF/LF ratio: 0.738 (0.507, 0.970)
    W/ Mask (Day)
    SBP: 109 (104, 114)
    DBP: 73 (70-76)
    MAP: 85 (81, 89)
    December 2009
    E-39
    

    -------
                Reference                      Design & Methods                   Concentrations1               Effect Estimates (95% Cl)
    
                                                                                                                    Heart Rate: 78 (73, 82)
                                                                                                                    Avg NN interval: 850 (805, 896)
                                                                                                                    pNNSO: 17.9 (14.2, 21.6)
                                                                                                                    RMSSD:37.1 (32.2,42.0)
                                                                                                                    SDNN: 65.5 (59.0, 72.2)*
                                                                                                                    Triangular index: 13.8 (13.0,14.5)
                                                                                                                    LF power: 919 (717,1122)*
                                                                                                                    HF power: 485 (400, 569)
                                                                                                                    LFn: 64.5 (60.6, 68.4)
                                                                                                                    HFn: 30.0 (27.0, 33.1)
                                                                                                                    HF/LF ratio: 0.680 (0.519, 0.842)
    
                                                                                                                    W/o Mask (During Walk)
                                                                                                                    SBP:  121 (115, 127)
                                                                                                                    DBP:  81 (75-87)
                                                                                                                    MAP: 94 (89, 99)
                                                                                                                    Heart Rate: 88 (82, 94)
                                                                                                                    Avg NN interval: 594 (562, 627)
                                                                                                                    pNNSO: 3.3 (0.8, 5.7)
                                                                                                                    RMSSD: 17.2 (13.4, 21.0)
                                                                                                                    SDNN: 45.8 (36.8, 54.8)
                                                                                                                    Triangular index: 10.7(9.1,12.4)
                                                                                                                    LF power: 313 (170, 455)
                                                                                                                    HF power: 76.5 (33.6, 120.0)
                                                                                                                    LFn: 68.2 (60.9, 75.5)
                                                                                                                    HFn: 16.1  (11.9, 20.3)
                                                                                                                    HF/LF ratio: 0.259 (0.173, 0.344)
    
                                                                                                                    VW Mask (During Walk)
                                                                                                                    SBP:  114 (108, 120)
                                                                                                                    DBP:  79 (74, 83)
                                                                                                                    MAP: 90 (86, 94)
                                                                                                                    Heart Rate: 91 (85, 97)
                                                                                                                    Avg NN interval: 613 (571, 655)
                                                                                                                    pNN50:2.1 (-0.1,-4.4)
                                                                                                                    RMSSD: 20.0 (15.5, 24.6)
                                                                                                                    SDNN: 54.8 (42.5, 67.0)
                                                                                                                    Triangular index: 11.4 (9.4,13.3)
    
                                                                                                                    W Mask (During Walk)
                                                                                                                    LF power: 414 (233, 595)
                                                                                                                    HF power: 116.8 (52.6,181.0)
                                                                                                                    LFn: 67.9 (61.9, 73.9)
                                                                                                                    HFn: 16.0 (12.5, 19.4)
                                                                                                                    HF/LF ratio: 0.247 (0.180, 0.314)
    
                                                                                                                    Mean (SD):
                                                                                                                    W/o Mask (After Walk)
                                                                                                                    Headache: 2.53 (5.55)
                                                                                                                    Dizziness: 1.07 (2.22)
                                                                                                                    Tiredness: 8.47 (12.14)
                                                                                                                    Sickness:  1.07 (2.22)
                                                                                                                    Cough: 1.80 (4.80)
                                                                                                                    Difficulty Breathing: 0.67 (0.90)
                                                                                                                    Eye irritation: 1.40(3.60)
                                                                                                                    Throat irritation: 1.47 (4.07)
                                                                                                                    Nose irritation: 1.53(3.78)
                                                                                                                    Unpleasant Smell: 0.93 (1.22)
                                                                                                                    Bad taste: 0.73 (0.96)
                                                                                                                    Difficulty walking: 12.53 (13.24)
                                                                                                                    Perception of Pollution: 19.80 (18.37)
    
                                                                                                                    W/Mask (After Walk)
                                                                                                                    Headache: 0.73 (1.03)
                                                                                                                    Dizziness: 0.80 (1.57
                                                                                                                    Tiredness: 7.40 (9.37)
                                                                                                                    Sickness: 0.87 (1.51)
                                                                                                                    Cough: 1.00 (1.73)
                                                                                                                    Difficulty Breathing: 3.80 (8.10)
                                                                                                                    Eye irritation: 1.67 (3.27)
                                                                                                                    Throat irritation: 1.07 (2.63)
                                                                                                                    Nose irritation: 1.07 (1.91)
                                                                                                                    Unpleasant Smell: 0.60 (0.91)
                                                                                                                    Bad taste: 0.60 (1.18)
                                                                                                                    Difficulty walking: 15.13 (11.51)
                                                                                                                    Perception of Pollution: 11.60 (10.44)
                                                                                                                    *p < 0.05
                                                                                                                    Notes: Estimates also available for 24 h,
                                                                                                                    night, before walk, and 24 h after walk.
    December 2009                                                     E-40
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Lanki et al. (2006, 0884121
    
    Period of Study: Fall 1998-spring 1999
    
    Location: Helsinki, Finland
    Outcome: ST segment depressions (2
    endpoints: >0.1mV regardless of the
    direction of the ST slope and >0.1mV
    with horizontal or downward slope
    [stricter criteria])
    
    Age Groups: Mean = 68.2 (6.5) yr
    
    Study Design: Panel
    
    N: 45 elderly nonsmoking persons with
    stable coronary heart disease
    
    342 total exercise tests for analyses
    
    Statistical Analyses: Generalized
    additive models with penalized splines
    (logistic regression)
    principal components analysis and linear
    regression of 13 measured elements
    used to apportion PM25 mass between
    different sources
    
    Covariates: Subject, linear terms for
    time trend, temperature, relative
    humidity, penalized spline for change in
    heart rate during the exercise test
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: S-plus 2000 and R
    Pollutant: PM25 (Analyses conducted
    for source specific PM25)
    
    Averaging Time: Daily filter samples
    
    Mean:
    Crustal: 0.6
    Long-range transported: 6.4
    Oil combustion: 1.6
    Salt: 0.9
    Local traffic: 2.9
    Total: 12.8
    
    Percentiles: Crustal
    25: 0.0
    50: 0.4
    75:1.1;
    Max: 5.3
    
    Long-range transported
    25:2.2
    50: 5.5
    75: 9.8;
    Max: 26.5
    
    Oil combustion
    25: 0.6
    50:1.3
    75:2.3;
    Max: 12.2
    
    Salt
    25: 0.3
    50: 0.8
    75:1.2;
    Max: 5.9
    
    Local traffic
    25:1.7
    50: 2.5
    75: 3.4;
    Max: 12.0
    
    Total
    25: 8.3
    50:10.6
    75:15.9;
    Max: 39.8
    
    Monitoring Stations: 1  monitor
    
    Copollutant (correlation):
    
    Correlations with PM25:
    
    Crustal: r =-0.01
    
    Long-range transported: r = 0.82
    
    Oil combustion: r = 0.35
    
    Salt: r = 0.19
    
    Local traffic: r = 0.26
    PM Increment: 1 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Adjusted ORs between daily source-
    specific  PM25 concentrations and
    ST-segment depressions. ST-segment
    depression defined as >0.1 mV (n = 62)
    
    Crustal
                                                                                                                    Lag 0: 0.80
                                                                                                                    Lag 1:0.66
               0.47, 1.36)
               0.40, 1.10)
                                                                                                                    Lag 2:1.18 (0.68, 2.06)
                                                                                                                    Lag 3:1.87 (0.85, 4.09)
    
                                                                                                                    Long-range transport
                                                                                                                    Lag 0:0.94 (0.84, 1.05)
                                                                                                                    Lag 1:1.00 (0.92,1.08)
                                                                                                                    Lag 2:1.11  (1.02,1.20)
                                                                                                                    Lag 3:1.06 (0.95,1.18)
    
                                                                                                                    Oil combustion
                                                                                                                    Lag 0:0.87 (0.57, 1.32)
                                                                                                                    Lag 1:1.04 (0.75,1.45)
                                                                                                                    Lag 2:1.10
                                                                                                                    Lag 3:1.12
               0.83, 1.46)
               0.79, 1.58)
                                                                                                                    Salt
                                                                                                                    LagO: 1.03 (0.57,1.85)
                                                                                                                    Lag1: 0.72 (0.37,1.40)
                                                                                                                    Lag2: 0.66 (0.31,1.40)
                                                                                                                    Lag3:1.55 (0.83, 2.89)
    
                                                                                                                    Local traffic
                                                                                                                    Lag 0:0.91  (0.69,1.21)
                                                                                                                    Lag 1:1.22
                                                                                                                    Lag 2:1.53
                                                                                          0.88, 1.69)
                                                                                          1.19,1.97)
                                                                                                                    Lag 3: 0.98 (0.78, 1.23)
    
                                                                                                                    ST-segment depression defined as >0.1
                                                                                                                    mV with horizontal or downward slope
                                                                                                                    (n = 46)
    
                                                                                                                    Crustal
                                                                                                                    LagO: 0.76 (0.42, 1.35)
                                                                                                                    Lag1:0.41 (0.22,0.79)
                                                                                                                    Lag2:1.17 (0.65, 2.09)
                                                                                                                    Lag3:1.60 (0.72, 3.59)
    
                                                                                                                    Long-range transport
                                                                                                                    Lag 0: 0.98 (0.86,1.10)
                                                                                                                    Lag 1:1.03 (0.95,1.12)
                                                                                                                    Lag 2: 1.11  (1.02, 1.21)
                                                                                                                    Lag 3:1.02 (0.95,1.10)
    
                                                                                                                    Oil combustion
                                                                                                                    Lag 0:0.95 (0.61,1.49)
                                                                                                                    Lag 1:1.13
                                                                                                                    Lag 2:1.33
                                                                                          0.76, 1.68)
                                                                                          0.98, 1.80)
                                                                                                                    Lag 3:1.29 (0.90, 1.86)
    
                                                                                                                    Salt
                                                                                                                    Lag 0:1.15
                                                                                                                    Lag 1:0.90
                                                                                          0.56, 2.38)
                                                                                          0.44, 1.81)
                                                                                                                    Lag 2:1.39 (0.63, 3.08)
                                                                                                                    Lag 3:1.93 (1.00, 3.72)
    
                                                                                                                    Local traffic
                                                                                                                    Lag 0:0.89 (0.64, 1.23)
                                                                                                                    Lag 1:1.21 (0.86,1.71)
                                                                                                                    Lag 2:1.37 (1.03,1.83)
                                                                                                                    Lag 3:1.03 (0.80,1.32)
    
                                                                                                                    Adjusted ORs for the association of
                                                                                                                    indicator elements of PM25 sources and
                                                                                                                    ST-segment depressions in
                                                                                                                    multipollutant models (models include all
                                                                                                                    5 indicator elements). ST-segment
                                                                                                                    depression defined as >0.1  mV (n = 62)
    
                                                                                                                    Si (Crustal)
                                                                                                                    LagO: 0.73 (0.39, 1.38)	
    December 2009
                                     E-41
    

    -------
                Reference                      Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                    Lag 1:0.48 (0.25, 0.93)
                                                                                                                    Lag2: 0.78 (0.35, 1.71)
                                                                                                                    Lag3:1.95 (0.69, 5.48)
    
                                                                                                                    S (Long-range transport)
                                                                                                                    LagO: 0.70 (0.25, 1.95)
                                                                                                                    Lag 1:0.58 (0.23, 1.47)
                                                                                                                    Lag2:1.08 (0.44, 2.63)
                                                                                                                    Lag3:1.60 (0.73, 3.48)
    
                                                                                                                    Ni (Oil combustion)
                                                                                                                    LagO: 0.78 (0.30, 2.04)
                                                                                                                    Lag 1:1.20 (0.58, 2.46)
                                                                                                                    Lag2:1.15(0.61,2.18)
                                                                                                                    Lag3:1.02 (0.41, 2.54)
    
                                                                                                                    Cl (Salt)
                                                                                                                    LagO: 1.03 (0.79,1.34)
                                                                                                                    Lag 1:0.88 (0.56, 1.38)
                                                                                                                    Lag2:1.02 (0.62, 1.69)
                                                                                                                    Lag3:1.27 (0.85,1.91)
    
                                                                                                                    ABS (Local traffic)
                                                                                                                    LagO: 0.92 (0.36, 2.37)
                                                                                                                    Lag 1:1.83 (0.73, 4.59)
                                                                                                                    Lag2: 4.46 (1.69, 11.79)
                                                                                                                    Lag3: 0.92 (0.40, 2.12)
    
                                                                                                                    ST-segment depression defined as >0.1
                                                                                                                    mV with horizontal or downward slope
                                                                                                                    (n = 46)
    
                                                                                                                    Si (Crustal)
                                                                                                                    LagO: 0.67 (0.33, 1.36)
                                                                                                                    Lag1: 0.34 (0.15, 0.81)
                                                                                                                    Lag2: 0.81 (0.33, 2.00)
                                                                                                                    Lag3:1.90 (0.64, 5.65)
    
                                                                                                                    S (Long-range transport)
                                                                                                                    LagO: 0.84 (0.29, 2.47)
                                                                                                                    Lag 1:0.89 (0.34, 2.32)
                                                                                                                    Lag2:1.36 (0.54, 3.45)
                                                                                                                    Lag3:1.12 (0.53, 2.40)
    
                                                                                                                    Ni (Oil combustion)
                                                                                                                    LagO: 1.10(0.36, 3.37)
                                                                                                                    Lag1:1.16 (0.45, 2.96)
                                                                                                                    Lag2:1.64 (0.84, 3.20)
                                                                                                                    Lag3:1.63 (0.64, 4.14)
    
                                                                                                                    Cl (Salt)
                                                                                                                    LagO: 1.13 (0.80,1.62)
                                                                                                                    Lag 1:0.99 (0.58, 1.68)
                                                                                                                    Lag2:1.55 (0.87, 2.76)
                                                                                                                    Lag3:1.45 (0.94, 2.25)
    
                                                                                                                    ABS (Local traffic)
                                                                                                                    LagO: 0.74 (0.25, 2.23)
                                                                                                                    Lag1:1.76 (0.62, 5.00)
                                                                                                                    Lag2: 4.86 (1.55, 15.26)
                                                                                                                    Lag3: 0.97 (0.39, 2.41)
    December 2009                                                     E-42
    

    -------
    Reference
    Reference: Lanki et al. (2008, 191984)
    
    Period of Study: Jan 1999-Apr 1999
    
    Location: Helsinki, Finland
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: ST Segment Depressions
    >0.1 mV
    
    Age Groups: 50+
    
    Study Design: Panel
    
    N: 41 elderly people w/CHD
    Statistical Analyses: Logistic
    Regression Model
    Covariates: Long-term time trend,
    temperature, humidity, change in heart
    rate following exercise test
    Dose-response Investigated? No
    Statistical Package: R
    Lags Considered: lags 0-24 h
    
    Concentrations1
    Pollutant: PM,5
    
    Averaging Time: Hourly
    
    26th, 60th, 76th, Max:
    
    Personal PM25
    1h:6.9, 11.2, 15.8, 41.5
    4h: 5.9, 10.0, 14.6, 41.3
    8h:5.0, 7.9, 13.0, 34.9
    12h: 5.2, 7.8, 12.1,28.8
    22h:6.6, 9.3, 13.0,30.2
    Outdoor PM2 5
    1h:8.9, 12.9, 17.8,42.9
    4h:8.8, 12.5, 17.6, 40.8
    8h:8.3, 12.1, 17.2,39.2
    12h: 8.3, 11.9, 17.0, 37.0
    24 h: 9.0, 12.5, 17.7, 30.5
    Monitoring Stations: 1
    Co-pollutant: PM<0.1
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    
    Odds Ratio (Lower Cl, Upper Cl):
    
    Personal PM2 5
    1-havg: 3.26 (1.07, 9.99)*
    4-h avg: 2.42 0.75, 7.83)
    8-havg:1.57 0.49,5.09)
    12-h avg: 1.96 (0.44, 8.64)
    22-h avg: 2.06 (0.30, 14.10)
    Outdoor PM2 5
    1-havg: 1.77 (0.87, 3.58)
    4-h avg: 2.47 (1.05, 5.85)*
    8-h avg: 1.83 (0.80, 4.20)
    12-h avg: 1.90 (0.77, 4.65)
    24-h avg: 1.60 (0.59, 4.39)
    *p < 0.05
    
    
                                                                          Co-pollutant Correlation
                                                                          Personals Outdoor PM2 5
                                                                          1 h&1 h:0.70
                                                                          4hS4h:0.54
                                                                          8hS8h:0.60
                                                                          12hS12h:0.50
                                                                          22hS24h:0.80
    Notes: 1-22 h pollutant averaging times.
    Correlations also available for personal-
    personal and outdoor-outdoor.
    Reference: Liao et al. (2007, 1802721 Outcome: Ectopy Pollutant: PM25
    Period of Study: 1999-2004 Age Groups: women 50-79 yr Averaging Time: Daily
    Location: 24 U.S. States Study Design: Panel Mean (SD)*:
    „„,„ All: 13.8 (79)
    N: 57>422 No Ectopy: 13.8 (7.9)
    Statistical Analyses: logistic regression AnV EctoPy; 13'8 <7'6'
    & random effects modeling 6th, 95th percentile*:
    AH1 5 29 1
    Covariates: Age, race, center, M V t ^ ?Q ?
    education, history of CVD/chronic lung A° SfL i ns OR *
    disease, rel. humidity, temperature, Any Ectopy. 5.06, 28.5
    smokin9 Monitoring Stations: NRJ
    Dose-response Investigated? No Copollutant: PM10
    Statistical Package: SAS, State Co-pollutant Correlation: NR
    Lags Considered: lags 0-365 days *|_ag 1
    ^Monitors used in model for spatial
    interpolation of daily PM values.
    PM Increment: 10 pg/m3
    Percent Change (Lower Cl, Upper Cl):
    All Ventricular Ectopy
    Lag 0:1. 01 (0.91, 1.1 3)
    Lag 1:1.07 (0.96, 1.20)
    Lag 2: 1.09 (0.98, 1.21)
    Current Smoker Ventricular Ectopy
    Lag 0:1. 52 (1.04, 2.24)
    Lag 1:2 (1.32, 3.03)
    Lag 2: 1.59 (0.99, 2.55)
    Nonsmoker Ventricular Ectopy
    Lag 0: 0.99
    Lag 1:1. 05
    0.89, 1.11)
    0.94, 1.17)
    Lag 2: 1.08 (0.97, 1.21)
    All Supraventricular Ectopy
    Lag 0:1. 04 (0.96, 1.13)
    Lag 1:1. 01
    Lag 2: 0.96
    0.93, 1.10)
    0.87, 1.05)
    All Ventricular or Supraventricular
    
    
    
    Ectopy
    Lag 0:1. 03
    Lag 1:1. 04
    
    0.96, 1.11)
    0.97,1.11)
    Lag 2:1 (0.94, 1.07)
    Reference: Lipsett et al. (2006, 0887531 Outcome: HRV parameters, specifically Pollutant: PM25
    PM Increment: SE*1 00
                                       SDNN, SDANN, r-MSSD, LF, HF, total
    Period of Study: Feb-May 2000        power] triangular index (TRII).
    Location: Coachella Valley, CA
                                       Study Design: Panel study
    
                                       N: 19 non-smoking adults with coronary
                                       artery disease
    
                                       Statistical Analysis: Mixed linear
                                       regression models with random effects
                                       parameters
        Averaging Time: 2 h
    
        Mean (range)
        Indio: 23.2 (6.3-90.4)
        Palm Springs: 14 (4.7-52)
    
        Monitoring Stations: 2
    
        Copollutant: 0;
    Effect Estimate (change in HRV per
    unit increase in PM concentration):
    SDNN: -0.37 msec (SE= 1.01)
    
    Notes: Weekly ambulatory 24 h ECG
    recordings (once per week for up to 12
    wk), using Holter monitors, were made.
    Subjects' residences were within 5 mi of
    1 of 2 PM monitoring sites. Decreased
    HRV was associated with PM2 5, but
    these effects were not statistically
    significant. Regressed HRV parameters
    against 18: 00-20:  00 mean particulate
    pollution.
    December 2009
    E-43
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ljungman et al. (2008,
    1802661
    
    Period of Study: Aug 2001-Dec 2006
    
    Location: Stockholm, Sweden
    Outcome: Ventricular Arrhythmia
    
    Age Groups: 28-85 yr
    
    Study Design: Case-crossover
    
    N: 88 patients w/ implantable
    cardioverter defibrillators
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature, humidity,
    pressure, ischemic heart disease,
    ejection fraction, heart disease,
    diabetes, use of beta-blockers, age,
    BMI, location at time of arrhythmia,
    distance from air pollution monitor
    
    Dose-response Investigated? No
    
    Statistical Package: Stata, S-plus
    
    Lags Considered: lags 2-24 h
    Pollutant: PM25
    
    Averaging Time: Hourly
    
    Median:
    2 h: 9.17
    24 h: 9.49
    
    Min:
    2 h: 0.15
    24 h: 2.97
    
    Max:
    2 h: 99.25
    24 h: 47.07
    
    IQR:
    2 h: 6.69
    24 h: 5.27
    
    Monitoring Stations: 1
    
    Copollutant: PM10, N02
    
    Co-pollutant Correlation: NR
    PM Increment: Interquartile Range
    
    Odds Ratio (Lower Cl, Upper Cl):
    2 h: 1.23 (0.84, 1.80)
    24 h: 1.28 (0.90, 1.84)
    
    Notes: OR of ventricular arrhythmia for
    an IQR increase of air pollutants in
    different subgroups (Fig 2)
    Reference: Ljungman et al. (2009,
    191983)
    Period of Study: May 2003-Jul 2004
    
    Location: Athens, Greece
    Helsinki, Finland
    Ausburg, Germany
    Barcelona, Spain
    Rome,  Italy
    Stokholm, Sweeden
    Outcome: lnterleukin-6 Response
    
    Age Groups: 35-80 yr
    
    Study Design: Panel
    
    N: 955 male myocardial infarction
    survivors
    
    Statistical Analyses: Additive Mixed
    Models
    
    Covariates: Age, sex, BMI, city,
    HDL/total cholesterol, smoking, alcohol
    intake, HbA1c, NT-proBNP, history of Ml,
    heart failure, or diabetes, phlegm
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 1 day
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean: 17.7
    26th: 10.9
    75th: 21.9
    
    Monitoring Stations: NR
    
    Copollutant: CO, N02,  PNC, PM25
    
    Co-pollutant Correlation:
    PM,0:0.81
    PM Increment: Interquartile Range
    Change of IL-6 (Lower Cl, Upper Cl),
    p-value:
    
    0.6 (-0.8, 2.0), 0.40
    Reference: Luttman-Gibson et al.
    (2006, 0897941
    
    Period of Study: Jun-Dec 2000
    
    Location: Steubenville, OH
    Outcome: Heart rate variability
    
    Age Groups:
    
    Study Design: Panel study
    
    N: 32 participants
    
    Statistical Analysis: Linear mixed
    models
    Pollutant: PM25
    
    Averaging Time:
    1 h
    24 h
    
    Mean (IQR)
    
    PM25: 20.0 (15.2)
    Sulfate:6.9(5.1)
    EC: 1.1 (0.6)
    
    Copollutant: N02, S02, 03
    PM Increment: IQR
    
    Percent change (96% Cl): Each
    13.4 pg/m3 increase in 24 h mean PM25
    concentration was associated with:
    SDNN: -4.0% (95% Cl: -7.0% to -0.9%)
    
    r-MSSD:-6.5%(95%CI:-12.1%to
    -0.6%)
    
    HF: -11.4% (95% Cl: -21.5% to -0.1%)
    
    Each 5.1 pg/m3 increase in sulfates on
    the previous day was associated with:
    SDNN: -3.3% (95% Cl: -6.0% to -0.5%)
    
    r-MSSD: -5.6% (95% Cl: -10.7%, 0.2%)
    
    HF: -10.3% (95% Cl: -19.5% to -0.1%)
    
    Notes: The authors conclude that
    increases in both traffic related particles
    and sulfates may adversely effect
    autonomic function.
    December 2009
                                    E-44
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Mar et al. (2005, 0875661
    
    Period of Study: 1999-2001
    
    Location: Seattle, WA
    Outcome: Change in arterial 02
    saturation, heart rate, and blood
    pressure (SBP and DBP)
    
    Age Groups: >75 yr
    
    Study Design:  Panel study
    
    N: 88 elderly subjects
    
    Statistical Analysis: GEE
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD):
    Personal: 9.3(8.4)
    Indoor: 7.4 (4.8)
    Outdoor: 9.0 (4.6)
    PM Increment: 10 pg/m
    
    Unit change in measure (96% Cl):
    Among all subjects: Each increase in
    outdoor same day PM2 5 was associated
    with: SBP: -0.81 mmHg (95% Cl: -2.34,
    0.73)
    
    DBP: -0.46 mmHg (95% Cl: -1.49 to
    0.57)
    
    H: -0.75 beats/min (95% Cl: -1.42 to
    -0.07)
    
    Each increase in indoor same day PM25
    was associated with: SBP: 0.92 mmHg
    (95% Cl:-2.04 to 3.87)
    
    DBP: 0.38 mmHg (95% Cl:-1.43 to
    2.20)
    
    H: 0.22 beats/min (95% Cl:-0.71 to
    1.16)
    
    Each increase in personal same day
    PM25 was associated with: SBP: 0.37
    mmHg (95% Cl:-0.93 to 1.67)
    
    DBP: -0.20 mmHg (95% Cl: -0.85 to
    0.46)
    
    H: 0.44 beats/min (95% Cl: 0.04to 0.84)
    
    Notes: Results by health status
    presented in Fig 1
    
    Used 2 sessions that each were 10
    consecutive days of measurements
    
    Used personal, indoor, and outdoor
    measures of PM25
    Reference: Metzger et al. (2007,
    0928561
    Period of Study: Aug 1998-Dec 2002
    Location: Atlanta, GA
    Outcome: Days with any event
    recorded by the ICD, days with ICD
    shocks/defibrillation and days with either
    cardiac pacing or defibrillation
    Study Design: Repeated measures
    N: 884 subjects between 1993 and 2002
    Statistical Analysis: Logistic regression
    with GEE to account for residual
    autocorrelation within subjects
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD):
    PM25: 17.8 (8.6)
    PM25sulfates:5.0(3.4)
    PM25EC:1.7(1.2)
    PM25OC:4.4(2.4)
    PM2 5 water-soluble metals: 0.029
    (0.024)
    Percentiles:
    PM25: Median: 16.2
    PM25sulfates: Median: 4.1
    PM25 EC: Median: 1.4
    PM25 OC: Median: 3.9
    PM2 5 water-soluble metals:
    Median: 0.022
    PM Increment: OR (96% Cl):
    Outcome = Any event recorded by ICD
    PM25
    OR = 1.00
    (95% Cl: 0.95, 1.04)
    PM25EC
    OR = 1.01
    (95% Cl: 0.98, 1.05)
    PM25OC
    OR = 1.01
    (95% Cl: 0.98, 1.03)
    PM25Sulfates
    OR = 0.99
    (95% Cl: 0.93, 1.06)
    PM25V\feter soluble metals
    OR = 0.95
    (95% Cl: 0.90, 1.00
                                                                           Copollutant:
                                                                           03
                                                                           N02
                                                                           CO
                                                                           S02
                                                                           Oxygenated hydrocarbons
    Reference: O'Neill et al. (2007, 0913621
    
    Period of Study: May 1998-Dec 2002
    
    Location: Boston, MA
    Outcome: Soluble intercellular adhesion  Pollutant: PM
    molecule 1 (ICAM-1)
    Vascular cell adhesion molecule 1
    (VCAM-1)
    
    von Willebrand factor (vWF)
    
    Age Groups: Mean (SD): 56.6 (10.6)
    Averaging Time: 24 h (lagged ma of
    days 0 to 1, 2, 3, 4, and 5)
    
    Mean (SD): 11.4 (5.9)
    
    Descriptive statistics represent entire
    study period
    PM Increment: IQR (specific to lag
    period)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change per IQR of PM2 5
    
    ICAM-1-All subjects
    Lag 0: 2.87 (-4.63, 10.95)
    2 dma: 2.25 (-5.15,10.22)
    Study Design: Cross-sectional
    N: 92 participants (type 2 diabetic
    patients)
    Percentiles: IQR range: 7.6
    Range (Min, Max): 0.07, 33.7)
    3 dma: 1.48
    4 dma: 1.80
    5 dma: 1.51
    6 dma: 2. 12
    -5.63, 9.11)
    -4.98, 9.07)
    -5.30, 8.80)
    -4.23, 8.89)
    December 2009
                                   E-45
    

    -------
                Reference
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                        Statistical Analyses: linear regression   Monitoring Stations: 1 site
                                        Covariates: Apparent temperature,
                                        season, age, race, sex, glycosylated
                                        hemoglobin, cholesterol, smoking
                                        history, BMI
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: NR
                                Copollutant:
                                PM25
                                BC.
                                S042"
                               Subjects not known to be taking
                               statins
                               Lag 0: 5.47 (-3.74, 15.57)
                               2 dma: 5.70 (-3.70,16.01)
                               3dma:4.57
                               4 dma: 4.57
           -4.31, 14.27
           -4.27, 14.23
                                                                    5 dma: 3.80 (-4.84, 13.22)
                                                                    6 dma: 3.79 (-4.49, 12.80)
    
                                                                    Subjects who report smoking in the
                                                                    past (but not within 6 mo)
                                                                    Lag 0: 0.9 (-9.56, 12.66)
                                                                                                               2 dma: 0.40
                                                                                                               3 dma: 1.34
                                                                               -12.08, 14.65)
                                                                               -9.23, 13.14)
                                                                                                               4 dma: 2.29 (-6.84, 12.30)
                                                                                                               5 dma: 1.09  -8.30,11.44)
                                                                                                               6 dma: 3.08  -6.30,13.40);
    
                                                                                                               Subjects who did not report smoking
                                                                                                               in the past
                                                                                                               Lag 0: 0.46 (-8.23, 9.97)
                                                                                                               2 dma: 1.37 (-7.96,11.65)
                                                                                                               3 dma:-0.96 (-10.01, 9.00)
                                                                                                               4 dma:-1.34 (-10.35, 8.58)
                                                                                                                5 dma: -0.87
                                                                                                                6 dma:-1.78
                                                                                -10.17, 9.40)
                                                                                -10.64, 7.94)
                                                                                                               VCAM-1- All subjects
                                                                                                               Lag 0: 6.88 (-2.88, 17.62)
                                                                    2 dma: 8.18
                                                                    3 dma: 6.92
                                                                                                                           -1.43, 18.72
                                                                                                                           -1.66,16.25
                                                                                                                4 dma: 6.46 (-1.16,14.66)
                                                                                                                5 dma: 8.57 (0.05,17.80)
                                                                                                                6 dma: 11.76 (3.48, 20.70)
    
                                                                                                                Subjects not known to be taking
                                                                                                                statins
                                                                                                                Lag 0:10.26 (-0.64, 22.35)
                                                                                                                2 dma: 15.02
                                                                                                                3 dma: 14.59
                                                                                 3.76, 27.49
                                                                                 3.94, 26.34
                                                                                                                4 dma: 15.15 (4.54, 26.84)
                                                                                                                5 dma: 16.16  5.77,27.58
                                                                                                                6 dma: 17.66  7.77,28.45
    
                                                                                                                Subjects who report smoking in the
                                                                                                                past (but not within 6 mo)
                                                                                                                Lag 0:13.2 (-1.30, 29.72)
                                                                                                                2 dma: 18.4 (0.69, 39.33)
                                                                                                                3 dma: 15.7 (1.19, 32.30)
                                                                                                                4 dma: 13.1
                                                                                                                5 dma: 13.2
                                                                               0.88, 26.78)
                                                                               0.49, 27.58)
                                                                                                                6 dma: 16.2 (3.76, 30.10)
    
                                                                                                                Subjects who did not report smoking
                                                                                                                in the past
                                                                                                                Lag 0:-3.12 (-12.41, 7.17)
                                                                                                                2 dma:-0.34 (-10.57,11.05)
                                                                                                                3 dma:-1.09 (-11.15,10.12)
                                                                                                                4 dma:-0.81 (-10.91,10.43)
                                                                                                                5 dma: 2.07 (-8.59, 13.96)
                                                                                                                6 dma: 4.89 (-5.56, 16.50)
    
                                                                                                                vWF-All subjects
                                                                                                                Lag 0:15.16 (-9.79, 47.01)
                                                                                                                2 dma: 12.57 (-9.19, 39.55)
                                                                                                                3 dma: 25.14 (-9.87, 73.74)
                                                                                                                4 dma: 23.42
                                                                                                                5 dma: 17.92
                                                                                 -9.47, 68.25)
                                                                                 -10.22, 54.87)
                                                                                                                6 dma: 20.48 (-8.82, 59.22)
    
                                                                                                                Subjects not known to be taking
                                                                                                                statins
                                                                                                                Lag 0:7.40 (-19.82, 43.88)
                                                                                                                2 dma: 7.10 (-19.09, 41.76)
                                                                                                                3 dma: 10.78 (-17.92, 49.52)
                                                                                                                4 dma: 11.61 (-16.64,49.42)
                                                                                                                5 dma: 9.15 (-20.32, 49.53)
                                                                                                                6 dma: 7.91 (-20.70,46.85)
    
                                                                                                                Subjects who report smoking in the
    December 2009
                            E-46
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                past (but not within 6 mo)
                                                                                                                Lag 0:19.23 (-24.29, 87.77)
                                                                                                                2dma:19.92
                                                                                                                3dma:29.54
                                                                                        -29.65,104.41)
                                                                                        -17.24, 102.76)
                                                                                                                4 dma: 41.98 (-6.95, 116.63)
                                                                                                                5 dma: 44.05 (-1.23,110.07)
                                                                                                                6 dma: 50.39 (9.35, 106.82)
    
                                                                                                                Subjects who did not report smoking
                                                                                                                in the past
                                                                                                                 Lag 0:-14.21 (-53.20,57.24)
                                                                                                                2 dma:-20.66 (-63.14, 70.77
                                                                                                                3 dma:-28.89 (-68.43, 60.19
                                                                                                                4 dma:-23.51 (-55.11, 30.34)
                                                                                                                5 dma:-29.18 (-60.08, 25.66)
                                                                                                                6 dma:-30.68 (-55.95, 9.08)
    Reference: O'Neill et al. (2007, 0913621
    
    Period of Study: May 1998-Dec 2002
    
    Location: Boston, MA
    Outcome: Soluble intercellular adhesion  Pollutant: BC
    molecule 1 (ICAM-1)
    Vascular cell adhesion molecule 1
    (VCAM-1)
    
    von Willebrand factor (vWF)
    
    Age Groups: Mean (SD): 56.6 (10.6)
    
    Study Design: Cross-sectional
    
    N: 92 participants (type 2 diabetic
    patients)
    
    Statistical Analyses: Linear regression
    
    Covariates: Apparent temperature,
    season, age, race, sex, glycosylated
    hemoglobin, cholesterol, smoking
    history, BMI
    
    Dose-response  Investigated? No
    
    Statistical Package: NR
    Averaging Time: 24 h (lagged ma of
    days 0 to 1,2, 3, 4, and 5)
    
    Mean (SD): 1.1 (0.8)
    
    descriptive statistics represent entire
    study period
    
    Percentiles: IQR range: 0.8
    
    Range (Min, Max): 0.2, 5.8
    
    Monitoring Stations: 1 site
    
    Copollutant:
    PM25
    BC.
    S042"
    PM Increment: IQR (specific to lag
    period)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change per IQR of BC
    
    ICAM-1--All subjects
    Lag 0: 5.09 (-2.37, 13.11)
    2 dma: 3.97 (-10.24, 20.42)
    3 dma: 5.10 (-10.17, 22.96)
    4 dma: 8.38 (-6.46, 25.56)
    5 dma: 10.09 -7.36,30.83
    6 dma: 10.58 -5.34,29.18
    
    Subjects not known to be taking
    statins
    Lag 0: 5.77 (-3.92, 16.44)
    2 dma: 2.39 (-7.65, 13.52)
    3 dma: 0.84 (-8.16,10.73)
                                                                                                                4 dma: 1.67
                                                                                                                5 dma: 1.55
                                                   -6.71, 10.80
                                                   -6.46, 10.24
                                                                                                                6 dma: 2.20 (-6.47,11.6
    
                                                                                                                Subjects who report smoking in the
                                                                                                                past (but not within 6 mo)
                                                                                                                Lag 0:5.84 (0.87, 11.05)
                                                                                                                2 dma: 5.08 (-2.34, 13.07)
                                                                                                                3 dma: 4.44 (-2.70,12.11)
                                                                                                                4 dma: 5.02
                                                                                                                5 dma: 5.89
                                                                                       -1.78, 12.29
                                                                                       -2.14, 14.58
                                                                                                                6 dma: 6.73 (-1.54,15.70)
    
                                                                                                                Subjects who did not report smoking
                                                                                                                in the past
                                                                                                                Lag 0:6.04 (0.87, 11.48)
                                                                                                                2 dma: 6.54 (-1.64, 15.39)
                                                                                                                3 dma: 5.86 (-1.90,14.22)
                                                                                                                4 dma: 6.11  (-1.18,13.94)
                                                                                                                5 dma: 6.89 (-1.42, 15.89)
                                                                                                                6 dma: 7.86 (-1.35, 17.94)
    
                                                                                                                VCAM-1-All subjects
                                                                                                                Lag 0:9.26 (2.98, 15.91)
                                                                                                                2 dma: 10.18 (1.93,19.10)
                                                                                                                3 dma: 15.45 (2.70, 29.78)
                                                                                                                4 dma: 17.97
                                                                                                                5 dma: 23.83
                                                                                        3.63, 34.30
                                                                                        8.41,41.44
                                                                                                                6 dma: 27.51 (11.96,45.21)
    
                                                                                                                Subjects not known to be taking
                                                                                                                statins
                                                                                                                Lag 0:9.19 (3.23, 15.49)
                                                                                                                2 dma: 14.64 (5.02, 25.14)
                                                                                                                3 dma: 14.39
                                                                                                                4 dma: 14.19
                                                                                        5.30, 24.28
                                                                                        5.71,23.36
                                                                                                                5 dma: 19.11 (9.44, 29.65)
                                                                                                                6 dma: 22.60 (11.79, 34.45)
    
                                                                                                                Subjects who report smoking in the
                                                                                                                past (but not within 6 mo)
                                                                                                                Lag 0:12.4 (2.77, 22.92)
                                                                                                                2 dma: 28.5 (8.38, 52.24)
                                                                                                                3 dma: 25.14 (3.50, 51.30)
                                                                                                                4 dma: 23.1  (2.70,47.58)	
    December 2009
                                    E-47
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                  5 dma: 32.0 (7.29, 62.30)
                                                                                                                  6 dma: 31.8 (9.74, 58.26)
    
                                                                                                                  Subjects who did not report smoking
                                                                                                                  in the past
                                                                                                                  Lag 0:5.15 (-5.63, 17.17)
                                                                                                                  2 dma: 2.09 (-9.07,14.61)
                                                                                                                  3 dma: 3.90 (-6.38,15.31)
                                                                                                                  4 dma: 4.92
                                                                                                                  5 dma: 7.89
                                                                                         -4.63, 15.43
                                                                                         -1.31, 17.95
                                                                                                                  6 dma: 10.97 (0.98, 21.96)
    
                                                                                                                  vWF-All subjects
                                                                                                                  Lag 0:7.96 (-4.34, 21.84)
                                                                                                                  2 dma: 14.87 (-2.85, 35.82)
                                                                                                                  3 dma: 15.34 (-3.22, 37.45)
                                                                                                                  4 dma: 15.47 (-7.60, 44.31)
                                                                                                                  5 dma: 19.50 -8.89,56.74
                                                                                                                  6 dma: 20.53 -9.80,61.05
                                                                                                                  Subjects not known to be taking
                                                                                                                  statins
                                                                                                                  Lag 0:3.23 (-8.91, 17.00)
                                                                                                                  2 dma: 9.82 (-8.39, 31.66)
                                                                                                                  3 dma: 17.79  (-16.03, 65.21)
                                                                                                                  4 dma: 13.14
                                                                                                                  5 dma: 16.14
                                                                                          -18.71,57.47)
                                                                                          -20.43, 69.52)
                                                                                                                  6 dma: 13.25 (-22.09, 64.62)
    
                                                                                                                  Subjects who report smoking in the
                                                                                                                  past (but not within 6 mo)
                                                                                                                  Lag 0:7.63 (-17.01, 39.58)
                                                                                                                  2 dma: 37.64 (-7.18, 104.10)
                                                                                                                  3 dma: 75.41 (6.16, 189.85)
                                                                                                                  4 dma: 72.05
                                                                                                                  5 dma: 73.14
                                                                                          -3.34, 206.22)
                                                                                          6.94, 180.32)
                                                                                                                  6 dma: 71.23 (14.00, 157.19)
    
                                                                                                                  Subjects who did not report smoking
                                                                                                                  in the past
                                                                                                                  Lag 0:10.22 (-23.14, 58.04)
                                                                                                                  2 dma: 17.07 (-18.86, 68.91)
                                                                                                                  3 dma: 6.56 (-42.75, 98.36)
                                                                                                                  4 dma:-9.20 (-65.79, 140.99)
                                                                                                                  5 dma:-23.86 (-71.05,  100.29)
                                                                                                                  6 dma:-48.69 (-77.75,  18.29)
    Reference: O'Neill et al. (2005, 0884231
    
    Period of Study:
    
    Baseline period: May 1998-Jan 2000
    Time trial: 2000-2002
    
    Location: Boston, MA
    Outcome: Changes in vascular
    reactivity, specifically percent change in
    brachial artery diameter (flow-mediated
    and nitroglycerin-mediated)
    Pollutant: PM25
    
    Mean (SD): 11.5 (6.4)
    
    Range: 1.1-40.0
    N: 270 patients with diabetes or at risk of  ./,.„:,....:„„ «»«„..• 1
    diabetes, who participated in non-air      Monitoring Stations. 1
    pollution related studies at the Joselyn
    Diabetes Center in Boston
                                         Statistical Analysis: Linear regression
    Copollutant:
    Sulfates
    BC
    Ultrafine particle counts
    PM Increment: IQR (value not given)
    
    Percent change (96% Cl): PM2 5 6-day
    ma
    
    Nitroglycerin-mediated reactivity: -7.6%
    (95% Cl: 12.8% to-2.1%)
    
    Notes: PM25 was positively associated
    with nitroglycerin-mediated reactivity
    an association was also reported with
    ultrafine particles. Effect estimates were
    larger in type II than type I diabetes. BC
    and sulfate increases were associated
    with decreased flow-mediated reactivity
    among those with diabetes. Although the
    largest associations were with the 6-day
    ma, similar patterns and quantitatively
    similar results appear  in the other lags.
    December 2009
                                     E-48
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: O'Neill et al. (2007, 0913621
    
    Period of Study: May 1998-Dec 2002
    
    Location: Boston, MA
    Outcome: soluble intercellular adhesion  Pollutant: S04'
    molecule 1 (ICAM-1)
    vascular cell adhesion molecule 1
    (VCAM-1)
    
    von Willebrand factor (vWF)
    
    Mean Age: 56.6 (10.6)
    
    Study Design: Cross-sectional
    
    N: 92 participants (type 2 diabetic
    patients)
    
    Statistical Analyses: Linear regression
    
    Covariates: Apparent temperature,
    season, age, race, sex, glycosylated
    hemoglobin, cholesterol, smoking
    history, BMI
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Averaging Time: 24 h (lagged ma of
    days 0 to 1, 2, 3, 4, and 5)
    
    Mean (SD): 3.0 (2.0)
    
    descriptive statistics represent entire
    study period
    
    Percentiles: IQR range: 2.2
    
    Range (Min, Max): 0.5, 9.6)
    
    Monitoring Stations: 1 site
    
    Copollutant: PM25, BC, S042"
    PM Increment: IQR (specific to lag
    period)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change per IQR of PM2 5
    
    ICAM-1 All subjects
    Lag 0: 5.30 (-2.60, 13.83)
    2 dma: 4.02 (-3.26,11.85)
    3 dma: 4.03 (-5.34, 14.34)
    4 dma:-0.79 (-7.30, 6.18)
    5 dma: 1.06 (-7.10, 9.93)
    6 dma: 3.15 (-5.66, 12.78)
    
    Subjects not known to be taking
    statins
    Lag 0:10.14 (0.44, 20.77)
    2 dma: 9.39 (-1.28, 21.20)
    3 dma: 10.93 (-2.23, 25.85)
    4 dma:-0.24 (-9.66,10.16)
    5 dma: 4.03 -8.66, 18.47
    6 dma: 5.66 -7.52,20.72
    
    Subjects who report smoking in the
    past (but not within  6 mo)
    Lag 0: -4.00 (-24.79, 22.52)
                                                                                                                 2 dma: -4.82
                                                                                                                 3 dma:-7.19
                                                                                         -18.01, 10.48)
                                                                                         -23.66, 12.83)
                                                                                                                 4 dma:-9.8 (-27.96, 12.97)
                                                                                                                 5 dma:-10.4 (-29.92, 14.44)
                                                                                                                 6 dma:-6.8 (-25.72, 17.03)
    
                                                                                                                 Subjects who did not report smoking
                                                                                                                 in the past
                                                                                                                 Lag 0: 6.67 (-4.34, 18.94)
                                                                                                                 2 dma: 5.65 (-4.67,17.10)
                                                                                                                 3 dma: 10.21 (-5.83, 28.99)
                                                                                                                 4 dma: 0.80
                                                                                                                 5 dma: 2.80
                                                                                        -9.94, 12.83)
                                                                                        -10.85, 18.54)
                                                                                                                 6 dma: 5.15 (-7.78, 19.89)
    
                                                                                                                 VCAM-1 All subjects
                                                                                                                 Lag 0:-0.04 (-3.75, 3.80)
                                                                                                                 2 dma: 0.94 (-4.79, 7.01)
                                                                                                                 3 dma:-0.87 (-3.50,1.82)
                                                                                                                 4 dma: 0.13 (-2.02, 2.34)
                                                                                                                 5 dma:-0.47 -2.67,1.78
                                                                                                                 6 dma:-0.46 -1.99,1.09
                                                                                                                 Subjects not known to be taking
                                                                                                                 statins
                                                                                                                 Lag 0:-1.34 (-11.23, 9.66)
                                                                                                                 2 dma:-0.19 (-11.13,12.09)
                                                                                                                 3 dma:-2.84 (-13.90, 9.64)
                                                                                                                 4 dma: 4.28 (-6.18,15.90)
                                                                                                                 5 dma:-0.26 (-13.44, 14.93)
                                                                                                                 6 dma:-3.44 (-16.51,11.67)
    
                                                                                                                 Subjects who report smoking in the
                                                                                                                 past (but not within 6 mo)
                                                                                                                 Lag 0: 0.07 (-23.40, 30.73)
                                                                                                                 2 dma:-5.62 (-20.77, 12.43)
                                                                                                                 3 dma:-26.92 (-33.31 to-19.91)
                                                                                                                 4 dma: -3.06
                                                                                                                 5 dma: -6.42
                                                                                         -28.01,30.56)
                                                                                         -30.75, 26.47)
                                                                                                                 6 dma: -6.46 (-28.55, 22.47)
    
                                                                                                                 Subjects who did not report smoking
                                                                                                                 in the past
                                                                                                                 Lag 0:-3.28 (-12.66, 7.12)
                                                                                                                 2 dma:-3.17 (-11.75, 6.23)
                                                                                                                 3 dma: -9.67
                                                                                                                 4 dma:-5.51
                                                                                         -22.07, 4.70)
                                                                                         -14.28, 4.15)
                                                                                                                 5 dma:-12.17 (-22.05 to-1.05)
                                                                                                                 6dma: -11.77 (-20.95to-1.52)
    
                                                                                                                 vWF (sulfate measures not available)
    December 2009
                                    E-49
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Park et al. (2008,1568451    Outcome: Total homocysteine (tHcy)    Pollutant: PM2
    Period of Study: Jan 1995-Jun 2005
    
    Location: Greater Boston area, MA
    Mean Age: 73.6 +6.9 yr
    
    Study Design: Cross-sectional and
    longitudinal analyses performed
    
    N:960 men
    Averaging Time: 24 h (ma up to 7 days
    prior to blood collection)
    
    Mean (SD): 12.0 (6.6)
    
    Median: 10.6
    Statistical Analyses: Generalized       Range (Min, Max): 2.0, 62.0
    additive models (also hierarchical mixed-
    effects regression models to assess
    repeated measures of tHcy)
                                                                             Monitoring Stations: 1 site
    
                                                                             Copollutant:
                                         Covariates: Model 1: season, age, long- PM25_
                                         termtrend, apparent temperature        BC(r-0.51)
    Model 2: further adjustment for BMI,
    systolic blood pressure, smoking status,
    pack yr of cigarettes, alcohol consump-
    tion
    
    Model 3: further adjustment for serum
    creatinine,  plasma folate, vitamin B6,
    and vitamin B12
    
    Dose-response Investigated? Modeled
    continuous covariates as penalized
    splines to determine if association with
    tHcy was linear
    
    Statistical Package: R software
                                                                             UL/ (r ~ u.oi j
                                                                             S04  (r = 0.85)
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Estimated % change in tHcy per IQR
    increase in pollutant.
    
    Lag model
    
    Concurrent day. IQR: 7.66
    Model 1:1.32 (-0.83, 3.52)
    Model 2:1.55 (-0.77, 3.91)
    Model 3:1.57 (-0.38, 3.56)
                                         1-day previous. IQR: 6.91
                                         Modell:-1.43 (-3.51, 0.69
                                         Model 2:-1.41 (-3.53, 0.76
                                         Model 3:-1.28 (-3.12, 0.60)
    
                                         2-day ma. IQR: 6.47
                                         Model 1:0.04 (-2.13, 2.26)
                                         Model 2:-0.07 (-2.26, 2.17)
                                         Model 3: 0.25 (-1.69, 2.22)
    
                                         3-day ma. IQR: 5.83
                                         Model!:-0.64 (-2.92, 1.69)
                                         Model 2:-0.74 (-3.04, 1.61
                                         Model 3:-0.59 (-2.63, 1.49
    
                                         4-day ma. IQR: 5.21
                                         Modell:-0.63 (-2.94, 1.72)
                                         Model 2:-0.86 (-3.19, 1.52
                                         Model 3:-0.73 (-2.78, 1.37
    
                                         5-day ma. IQR: 4.68
                                         Model!:-0.51 (-2.79, 1.83)
                                         Model 2:-0.82 (-3.13, 1.54)
                                         Model 3:-0.84 (-2.85, 1.22)
    
                                         6-day ma. IQR: 4.50
                                         Model!:-0.91 (-3.32, 1.56)
                                         Model 2:-1.32 (-3.76, 1.17)
                                         Model 3:-1.44 (-3.58, 0.74)
    
                                         7-day ma. IQR: 4.20
                                         Modell:-0.84 (-3.27, 1.64
                                         Model 2:-1.19 (-3.64, 1.33
                                         Model 3:-1.69 (-3.84, 0.51)
                                                                                                                  Stratified analyses: No significant
                                                                                                                  difference in effect of PM25 among those
                                                                                                                  with high and low levels of vitamins
    December 2009
                                     E-50
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Park et al. (2008,1568451    Outcome: Total homocysteine (tHcy)     Pollutant: BC
    Period of Study: Jan 1995-Jun 2005
    
    Location: Greater Boston area, MA
    Mean Age: 73.6 +6.9 yr
    
    Study Design: cross-sectional and
    longitudinal analyses performed
    
    N:960 men
    Averaging Time: 24 h (ma up to 7 days
    prior to blood collection)
    
    Mean (SD): 0.99 (0.56)
    
    Median: 0.87
                                         Statistical Analyses: Generalized       Range (Min, Max): 0.07, 3.7
                                         additive models (also hierarchical mixed-
                                         effects regression models to assess
                                         repeated measures of tHcy)
                                                                             BC
                                                                             OC(r = 0.0.51)
                                                                             S04 (r = 0.50)
                                         Monitoring Stations: 1 site
    
                                         Co pollutant
    Covariates: Model 1: season, age, long-  ,,nr...,..tjnn\.
    term trend, apparent temperature        PM2 5 (r = 0 51)
    
    Model 2: further adjustment for BMI,
    systolic blood pressure, smoking status,
    pack yr of cigarettes, alcohol
    consumption
    
    Model 3: further adjustment for serum
    creatinine,  plasma folate, vitamin B6,
    and vitamin B12
    
    Dose-response Investigated? Modeled
    continuous covariates as penalized
    splines to determine if association with
    tHcy was linear
    
    Statistical Package: R software
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Estimated % change in tHcy per IQR
    increase in pollutant.
    
    Lag model Concurrent day. IQR: 0.66
    Model 1:2.64 (-0.12, 5.48)
                                                                              Model 2: 2.62
                                                                              Model 3: 3.13
                                                      -0.17, 5.48)
                                                      0.76, 5.55)
                                         1-day previous. IQR: 0.66
                                         Model 1:1.46 (-0.98, 3.96)
                                         Model 2:1.32 (-1.14, 3.85)
                                         Model 3: 0.95 (-1.12, 3.05)
    
                                         2-day ma. IQR: 0.60
                                         Model 1:2.75
                                         Model 2: 2.63
                 -0.18, 5.76
                 -0.33, 5.67
                                                                                                                  Model 3: 2.59 (0.10,5.14)
    
                                                                                                                  3-day ma. IQR: 0.57
                                                                                                                  Model 1:2.95
                                                                                                                  Model 2: 2.97
                                                      -0.44, 6.46
                                                      -0.46, 6.51
                                                                                                                  Model 3: 3.12 (0.21, 6.11)
    
                                                                                                                  4-day ma. IQR: 0.52
                                                                                                                  Model 1:3.94 (0.24, 7.78)
                                                                                                                  Model 2: 3.76
                                                                                                                  Model 3: 3.00
                                                      0.02, 7.64)
                                                      -0.13, 6.22)
                                                                                                                  5-day ma. IQR: 0.49
                                                                                                                  Model 1:3.26 (-0.60, 7.27)
                                                                                                                  Model 2: 2.64 -1.23,6.67
                                                                                                                  Model 3: 2.38 -0.89, 5.77
    
                                                                                                                  6-day ma IQR: 0.44
                                                                                                                  Model 1:1.63 (-1.99, 5.38)
                                                                                                                  Model 2:1.03 (-2.62, 4.80)
                                                                                                                  Model 3: 0.93 (-2.15, 4.11)
    
                                                                                                                  7-day ma. IQR: 0.44
                                                                                                                  Model 1:1.38 (-2.45, 5.36)
                                                                                                                  Model 2: 0.69 (-3.16, 4.70)
                                                                                                                  Model 3: 0.45 (-2.81, 3.83)
    
                                                                                                                  % change in tHcy per IQR increase in
                                                                                                                  BC, 24-h avg
    
                                                                                                                  Among those with low folate: 5.31 (2.26,
                                                                                                                  8.42)
    
                                                                                                                  Among those with low B12: 5.06 (2.03,
                                                                                                                  8.17)
    
                                                                                                                  nearly null associations among those
                                                                                                                  with high levels
    December 2009
                                    E-51
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Park et al. (2008,1568451   Outcome: Total homocysteine (tHcy)     Pollutant: OC
    Period of Study: Jan 1995-Jun 2005
    
    Location: Greater Boston area, MA
    Mean Age: 73.6 +6.9 yr
    
    Study Design: Cross-sectional and
    longitudinal analyses performed
    
    N:960 men
    Averaging Time: 24 h (ma up to 7 days
    prior to blood collection)
    
    Mean (SD): 3.5 (1.8)
    
    Median: 3.1
                                        Statistical Analyses: Generalized       Range (Min, Max): 0.29,11!
                                        additive models (also hierarchical mixed-
                                        effects regression models to assess      Monitoring Stations: 1 site
                                        repeated measures of tHcy)
                                                                             Copollutant (correlation):
                                        Covariates: Model 1: season, age, long-  PM2= (r - 0.51)
                                        term trend, apparent temperature        BC (r - °'51)
    
                                        Model 2: further adjustment for BMI, sys-  S042" (r = 0.41)
                                        tolic blood pressure, smoking status,
                                        pack yr of cigarettes, alcohol consump-
                                        tion
    
                                        Model 3: further adjustment for serum
                                        creatinine, plasma folate, vitamin B6,
                                        and vitamin B12
    
                                        Dose-response Investigated? Modeled
                                        continuous covariates as penalized
                                        splines to determine if association with
                                        tHcy was linear
    
                                        Statistical Package: R software
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Estimated % change in tHcy per IQR
    increase in pollutant.
    
    Lag model
    
    Concurrent day. IQR: NA
    Model 1:NA
    Model 2: NA
    Model 3: NA
    
    1-day previous. IQR: 2.00
                                                                             Model 1:2.12
                                                                             Model 2:1.69
                                                     -0.98, 5.31
                                                     -1.51,5.00
                                                                             Model 3:1.87 (-0.81, 4.62)
    
                                                                             2-day ma. IQR: 1.93
                                                                             Model!:-0.39 (-3.67, 3.01
                                                                             Model 2: -0.88 (-4.26, 2.61
                                                                             Model 3:1.05 (-1.86, 4.06)'
    
                                                                             3-day ma. IQR: 1.68
                                                                             Model 1:0.53 (-2.66, 3.83)
                                                                             Model 2: 0.14  -3.15,3.54
                                                                             Model 3:1.32  -1.44,4.16
    
                                                                             4-day ma. IQR: 1.64
                                                                             Model 1:1.57 (-1.89, 5.15)
                                                                             Model 2:1.42  -2.14,5.12
                                                                             Model 3:1.89  -1.15,5.03
    
                                                                             5-day ma, IQR: 1.60
                                                                             Model 1:2.27 (-1.49, 6.16)
                                                                             Model 2: 2.11 (-1.77,6.15)
                                                                             Model 3: 2.12 (-1.29, 5.65)
    
                                                                             6-day ma. IQR: 1.43
                                                                             Model 1:2.83 (-0.74, 6.52)
                                                                             Model 2: 2.78 (-0.90, 6.60)
                                                                             Model 3: 2.53 (-0.59, 5.74)
    
                                                                             7-day ma. IQR: 1.23
                                                                                                                 Model 1:2.75
                                                                                                                 Model 2: 2.55
                                                                                          -0.41,6.02
                                                                                          -0.71,5.92
                                                                                                                 Model 3: 2.55 (-0.21, 5.39)
    
                                                                                                                 % change in tHcy per IQR increase in
                                                                                                                 OC, 7-day avg.
    
                                                                                                                 Among those with low B12: 5.23 (1.59,
                                                                                                                 9.01)
    
                                                                                                                 Nearly null associations among those
                                                                                                                 with high levels
    December 2009
                                    E-52
    

    -------
    Reference
    Reference: Park et al. (2005, 0573311
    Period of Study: Nov 2000-Oct 2003
    Location: Greater Boston area, MA
    Design & Methods
    Outcome: Change in HRV (SDNN, HF,
    LF, LFHFR)
    Mean age: 72.7 yr
    Study Design: Cross-sectional
    N: 497 adult males living in the Greater
    Boston, MA area
    Concentrations1
    Pollutant: PM25
    Averaging Time:
    4h
    24 h
    48 h
    Mean (SD): 11. 4 (8.0)
    Range: 6.45-62.9
    Effect Estimates (95% Cl)
    PM Increment: 8 pg/m3
    Percent change (96% Cl): 48h mean
    PM25: 20.8% decrease in HF (95% Cl:
    4.6%, 34.2%)
    18.6% increase in LFHFR (4.1%,
    35.2%).
    Notes: Subjects were monitored during
                                                                             Copollutant:
                                                                             03, Particle number count, BC, N02,
                                                                             SO,, CO
                                                                             a 4-min rest period between 8 a.m. and
                                                                             1 p.m.  Modifying effects of hypertension,
                                                                             IHD, diabetes, and use of cardiac/anti-
                                                                             hypertensive medications also
                                                                             examined. Linear regression analyses.
                                                                             This subject group is from the VA
                                                                             Normative Aging Study. The 4-h
                                                                             averaging period was most strongly
                                                                             associated with HRV indices. The PM
                                                                             effect was robust in models including 03.
                                                                             The HRV change per IQR increase in
                                                                             PM25 were larger in subjects with
                                                                             hypertension (n = 335)  IHD (n =  142),
                                                                             and diabetes (n = 72). In addition, those
                                                                             who did not use calcium-channel
                                                                             blockers had a greater decline in LF
                                                                             associated with each IQR increase in
                                                                             PM25 than did those who did use
                                                                             calcium channel blockers. IQR increases
                                                                             in 48h  mean BC concentration were also
                                                                             associated with adverse changes in
                                                                             HRV, suggesting traffic pollution  may be
                                                                             particularly toxic.
    Reference: Park et al. (2006, 0912451
    Period of Study: Nov 2000-Dec 2004
    Location: Greater Boston area, MA
    Outcome: Change in HF
    Study Design: Cross-sectional
    N: Statistical Analysis: Linear
    regression models
    Pollutant: PM25
    Averaging Time: 48 h
    Mean (SD):
    PM25: 11.7 (7.8)
    Sulfates: 3.3 (3.3)
    BC: 0.92 (0.46)
    Copollutant: 0;
    PM Increment: 10 pg/m3
    Percent change (96% Cl): Wild-type
    HFE genotype: 31.7% (95% Cl: 10.3,
    48.1)
    Among those with either of the 2 HFE
    variants, there was no association
    between 48h PM25 and HF (shown in a
    graph, ~10% non-significant increase).
                                                                                                                  Notes: Normative Aging Study.
                                                                                                                  Examining association between PM and
                                                                                                                  HF among those with and without the
                                                                                                                  wild-type HFE genotype.
    Reference: Pekkanen et al. (2002,
    0350501
    
    Period of Study: Winter 1998-1999
    
    Location: Helsinki, Finland
    Outcome: ST-Segment Depression
    (>0.1mV)
    
    Study Design: Panel of ULTRA Study
    participants
    
    N: 45 Subjects, n = 342 biweekly
    submaximal exercise tests, 72 exercise
    induced ST Segment Depressions
    
    Statistical Analysis: Logistic regression
    /GAM
    Pollutant: PM25
    
    Averaging Time: 24 h
    Median: 10.6
    IQR: 7.9
    
    Pollutant: PM1
    Median: 7.0
    IQR: 5.6
    
    Pollutant: ACP (100 to 1000nm) (n/cm3)
    Median: 1200
    IQR: 760
    
    Copollutant: N02, CO, PM10.25, ultrafine
    PM Increment: IQR
    
    Effect Estimate(s): ACP: OR = 3.29
    (1.57, 6.92), lag 2
    
    PM,: OR = 4.56 (1.73, 12.03), lag 2
    PM2.5: OR = 2.84 (1.42, 5.66), lag 2
    
    Notes: The effect was strongest for ACP
    and PM25, which in 2 pollutant models
    appeared independent. Increases in N02
    and CO were also associated with
    increased risk of ST-segment
    depression, but not with coarse particles.
    December 2009
                                    E-53
    

    -------
                Reference
            Design & Methods
                                                 Concentrations1
        Effect Estimates (95% Cl)
    Reference: Park et al. (2008,1568451
    
    Period of Study: Jan 1995-Jun 2005
    
    Location: Greater Boston area, MA
    Outcome: Total homocysteine (tHcy)     Pollutant: S04'
    Mean Age: 73.6 +6.9 yr
    
    Study Design: Cross-sectional and
    longitudinal analyses performed
    
    N: 960 men
                                         Averaging Time: 24 h (ma up to 7 days
                                         prior to blood collection)
    
                                         Mean (SD): 3.2 (3.0)
    
                                         Median: 2.4
    Statistical Analyses: Generalized       Range (Min, Max): 0.39, 29.0
    additive models (also hierarchical mixed-
    effects regression models to assess
    repeated measures of tHcy)
    Covariates: Model 1 : season, age, long-
    term trend, apparent temperature
    
    Model 2: further adjustment for BMI,
    systolic blood pressure, smoking status,
    pack yr of cigarettes, alcohol consump-
    tion
    
    Model 3: further adjustment for serum
    creatinine,  plasma folate, vitamin B6,
    and vitamin B12
    
    Dose-response Investigated? Modeled
    continuous covariates as penalized
    splines to determine if association with
    tHcy was linear
    
    Statistical Package: R software
                                                                              Monitoring Stations: 1 site
    
                                                                              Copollutant (correlation):
                                                                                   (r - 0.85)
                                                                              BC(r-O.SO)
                                                                              UL/ (f ~ U.41 J
                                                                              S04
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Estimated % change in tHcy per IQR
    increase in pollutant.
    
    Lag model
    
    Concurrent day: IQR: NA
    Model 1:NA
    Model 2: NA
    Model 3: NA
    
    1-day previous: IQR:  2.61
                                                                              Model 1:0.91
                                                                              Model 2: 0.99
                 -0.77, 2.62
                 -0.94, 2.95
                                                                              Model 3: 0.91 (-0.72, 2.57)
    
                                                                              2-day ma: IQR: 2.10
                                                                              Model!:-0.25 (-2.07, 1.60
                                                                              Model 2:-0.29 (-2.35, 1.82
                                                                              Model 3: 0.05 (-1.74, 1.86)'
    
                                                                              3-day ma: IQR: 1.73
                                                                              Model!:-0.15 (-1.97, 1.69)
                                                                              Model 2:-0.17 (-2.23, 1.93
                                                                              Model 3: -0.01 (-1.78,1."
    
                                                                              4-day ma: IQR: 1.64
                                                                              Model!:-0.69 (-2.74, 1.41)
                                                                              Model 2:-0.60 (-2.95, 1.81
                                                                              Model 3:-0.58 (-2.63, 1.51
    
                                                                              5-day ma: IQR: 1.60
                                                                              Modell:-1.14 (-3.53, 1.30)
                                                                              Model 2:-0.90 (-3.64, 1.92)
                                                                              Model 3:-1.09 (-3.48, 1.36)
    
                                                                              6-day ma;' IQR:  1.40
                                                                              Model 1:0.00 (-2.39, 2.44)
                                                                              Model 2: 0.36 (-2.36, 3.16)
                                                                              Model 3: 0.41 (-2.01,2.89)
    
                                                                              7-day ma
                                                                              IQR: 1.30
                                                                              Modell:-0.16 (-2.51, 2.24)
                                                                              Model 2: 0.30 (-2.37, 3.04)
                                                                              Model 3: 0.07 (-2.25, 2.43)
                                                                                                                  Stratified analyses: No significant
                                                                                                                  difference in effect of SO?' among those
                                                                                                                  with high and low levels of vitamins
    Reference: Peters et al. (2005, 0957471
    Also Peters et al. (2005,1568591
    
    Period of Study: Feb 1999-Jul 2001
    
    Location: Augsburg, Germany
    Outcome: Myocardial infarction
    
    Study Design: Case-crossover
    
    N: 691  myocardial infarction patients
                                         Pollutant: PM25
                                         Averaging Time:
                                         1 h: Median = 14.5
                                         IQR: 9.1
    Statistical Analysis: Conditional logistic  ^"h:,M,edlan = 149
    regression                            u
                                         Dose-response Investigated? No
                                                                              Copollutant: N02, S02, CO
    Effect Estimate: 2-h lag: OR = 0.93
    
    95% 0:0,83,1.04
    24-h mean, 2-day lag: OR = 1.18
    95% Cl: 1.03, 1.34
    
    Notes: Examined triggering for Ml at
    various lags before Ml onset (up to 6 h
    before Ml,  up to 5 days before Ml). PM2 5
    levels 2 days before Ml onset were
    associated with increased risk of Ml, but
    not on the concurrent day, or lags 1, 3,
    4, or 5. These findings are consistent
    with the prior Boston Ml study  for a 1- to
    2-day lagged effect of PM2 5.
    December 2009
                                     E-54
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Pope et al. (2004, 0552381
    Period of Study: Winter 1999-2000 (in
    Wasatch Front, UT). Summer 2000 (in
    Hawthorne, UT).
    Winter 2000-2001 (in Bountiful, UT and
    Lindon, UT)
    Location:  Utah: Wasatch Front,
    Hawthorne, Bountiful, and Lindon
    Outcome: Change in autonomic         Pollutant: PM25 (TEOM)
    function (measured by changes in HRV),
    C-reactive protein (CRP), blood cell      Averaging Time: 24 h
    counts, platelets, and blood viscosity
    associated with short-term changes in
    PM25
    Mean (SD): 18.9 (13.4)
    Copollutant: None
    Age Groups: Elderly (specific age range
    not given)
    Study Design: Panel study
    N: 88 elderly subjects
    Statistical Analysis: Linear regression
    Season: Wnter, summer
    Dose-response Investigated? No
    PM Increment: 100 pg/m
    Effect Estimate: Each 100 pg/m3
    increase associated with: -35 (SE = 8)
    msec decline in SDNN
    0.81 (SE 0.17) mg/dL increase in CRP
    0.31 (SE 9.34) k/pL increase in platelets
    0.07 (SE 0.21) cP increase in blood
    viscosity
    Notes: The study observed small but
    statistically significant adverse
    associations between daily mean PM25
    and HRV and C-reactive protein (CRP).
    The authors point out,  however, that
    most of the variability in the temporal
    deviation of these physiological
    endpoints was not explained by PM2 5.
    These observations therefore suggest
    that PM25 may be 1 of multiple factors
    that influence HRV and CRP.
    Reference: Pope et al. (2006, 0912461   Outcome: Acute ischemic heart disease Pollutant: PM25 (FRM)
    Period of Study: 1994-2004
    Location: Wasatch Front, Utah
    Study Design: Case-crossover study
    (time-stratified control selection)
    N: Statistical Analysis: Conditional
    logistic regression
    Averaging Time: 24 h
    Mean (SD): Site 1:10.1
    Site 2:10.8
    Site 3:11.3
    Monitoring Stations: 3
    Copollutant: PM10 (FRM) measured at
    4 monitoring sites
    PM Increment: 10 pg/m
    Effect Estimate: For same-day increase
    inPM25:OR = 1.045
    95% Cl: 1.011, 1.080
    Notes: Case-crossover study (time-
    stratified control selection) triggering of
    acute ischemic heart disease by ambient
    PM25 concentrations on the same and
    previous 3 days. PM25 measured at 3
    sites and estimated for missing days.
    Effect estimates were larger for those
    with angiographically demonstrated
    coronary artery disease.
    Reference: Pope et al. (2004, 0552381
    Period of Study: 1999-2001
    Location: Wasatch Front, Utah
    Outcome: Heart rate variability (HRV)
    C-reactive protein (CRP)
    Blood cell counts, whole blood viscosity
    Age Groups: 54-89 yr
    Study Design: Panel study
    N: 88 participants
    Statistical Analyses: Linear regression
    Covariates: Subject-specific fixed
    effects
    Interactive spline smooths for temp, RH
    (partial control for H)
    Season: Temperature as covariate
    Dose-response Investigated?
    Yes, also assessed PM by including
    cubic smoothing splines with 3 df
    Statistical Package: SAS
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 23.7 (20.2)
    Range (Min, Max): 1.7, 74.0
    Monitoring Stations: NR
    Copollutant: None
    PM Increment: 100 pg/m
    Effect Estimate [Lower Cl, Upper Cl]:
    Regression coefficients (SE) for
    associations with concurrent day
    pollutant: Mean H:-4.49 (1.73)
    SDNN: -34.94 (8.32)
    SDANN:-18.98 (8.67)
    r-MSSD: -42.25 (10.90)
    CRP: 0.81 (0.18)
    Whole blood viscosity: 0.07 (0.21)
    WBC: -0.07 (0.38)
    Granulocytes: 0.02 (0.37)
    Lymphocytes:-0.07 (0.14)
    Monocytes:0.12(0.04)
    Basophils:-0.01  (0.01)
    Eosinophils: -0.01 (0.02)
    RBC: 0.03 (0.06)
    Platelets: 0.31 (9.34)
    Reference: Rich et al. (2005, 0796201
    Period of Study: Jul1995-Jul 2002
    Location: Eastern Massachusetts, USA
    Outcome: Confirmed ventricular
    arrhythmias
    Study Design: Case-crossover (time-
    stratified control selection)
    N: 203 patients with implantable
    cardioverter defibrillators
    Statistical Analysis: Conditional logistic
    regression
    Pollutant: PM25 (TEOM)
    Averaging Time: 1-h avg
    24-h avg
    Median (IQR):
    1-h avg: Median = 9.2 pg/m3
    24-h avg: Median = 9.8 pg/m3
    IQr = 7.8
    Copollutant: 03, BC, CO, N02, S02
    PM Increment: 7.8 pg/m
    Effect Estimate: For mean PM25 in the
    24 h before ventricular arrhythmia: OR
    = 1.19
    95% 0:1.02,1.38
    Notes: 794 ventricular arrhythmias
    among 84 subjects.
    Lag h: 0-2, 0-6, 0-23, 0-47
    December 2009
                                    E-55
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Rich et al. (2006, 0884271
    Period of Study: Jul 1995-Jul 2002
    Location: Eastern Massachusetts, USA
    Outcome: Confirmed episodes of
    paroxysmal atrial fibrillation
    Study Design: Case-crossover (time-
    stratified control selection)
    N: 203 patients with implantable
    cardioverter defibrillators
    Statistical Analysis: Conditional logistic
    regression
    Pollutant: PM25 (TEOM)
    Averaging Time: 1-h avg
    24-h avg
    Median (IQR):
    1-h avg: Median = 9.2 pg/m3
    24-h avg: Median = 9.8 pg/m3
    IQr = 7.8
    Copollutant: 03, BC, CO, N02, S02
    PM Increment: 9.4 pg/m
    Effect Estimate: 0-h lag: OR 1.41 (0.82,
    2.42)
    Notes: 91  paroxysmal atrial fibrillation
    (PAF) episodes among 29 subjects.
    Lag h:  0, 0-23
    Positive, but not significant increases in
    the relative odds of PAF associated with
    PM25 concentrations in the same h and
    24-h before PAF episode onset. Authors
    note reduced statistical power for PM25
    analyses due to missing data.
    Reference: Rich et al. (2006, 0884271
    Period of Study: Jul 1995-Jul 2002
    Location: Eastern Massachusetts, USA
    Outcome: Confirmed episodes of
    paroxysmal atrial fibrillation
    Study Design: Case-crossover (time-
    stratified control selection)
    N: 203 patients with implantable
    cardioverter defibrillators
    Statistical Analysis: Conditional logistic
    regression
    Pollutant: BC
    Averaging Time: 1-h avg, 24-h avg
    Median (IQR):  IQR: 0.91 pg/m3
    Copollutant: 03, PM25, CO, N02, S02
    PM Increment: 0.91 pg/m3 (IQR)
    Effect Estimate: 0- to 23-h lag period:
    OR 1.46 (95% 0:0.67,3.17)
    Notes: 91  paroxysmal atrial fibrillation
    (PAF) episodes among 29 subjects.
    Lag h:  0, 0-23
    Positive, but not significant increases in
    the relative odds of PAF associated with
    BC concentrations in the same h and 24
    h before PAF episode onset. Authors
    note reduced statistical power for BC
    analyses due to missing data.
    Reference: Rich et al. (2006, 0898141
    Period of Study: May 2001-Dec 2002
    Location: St. Louis, MO metropolitan
    area
    Outcome: Confirmed ventricular
    arrhythmia
    Study Design: Case-crossover design
    (time-stratified control selection)
    Dose-response Investigated? No
    Pollutant: PM25 (CAMM)
    Averaging Time: 24 h
    Median (IQR): 16.2 |jg/m3(IQr = 9.7)
    Copollutant: N02, S02, CO, 03, EC, OC
    PM Increment: 9.7 pg/rri (IQR)
    Effect Estimate: OR (PM25) = 0.95
    (95% Cl: 0.72, 1.27)
    OR (S02) = OR = 1.24 (95% Cl: 1.07,
    1.44)
    Notes: 139 confirmed ventricular
    arrhythmia episodes among 56 subjects.
    Lags:0-2h, 0-6h, 0-11h,  0-23h, 0-47h
    Authors did not find increased relative
    odds of VA associated with each IQR
    increase in 24-h mean PM25, but did find
    non-significantly increased relative odds
    of VA associated with 24-h EC.  Shorter
    and longer lag times' relative odds
    estimates provided no evidence of
    immediate ventricular arrhythmic effects
    of air pollution.
    Reference: Rich et al. (2004, 0556311
    Period of Study: Feb-Dec 2000
    Location: Vancouver, British Columbia,
    Canada
    Outcome: ICD discharges (as a proxy
    forVTA/F)
    Age Groups: 15-85yr
    Study Design: Case-crossover design
    (ambidirectional control selection + 7
    days)
    N: 34 patients with implantable
    cardioverter defibrillators
    Statistical Analysis: Conditional logistic
    regression
    Dose-response Investigated? No
    Pollutant: PM25 (Partisol)
    Averaging Time: 1 h
    Mean (SD), IQR:
    Mean:: 8.2 pg/m3(SD= 10.7)
    IQr = 5.2
    Copollutant: 03, EC, OC, S042", CO,
    N02, S02, PM,o
    PM10: Mean::  13.3 pg/m3
    (SD = 4.9)
    IQr = 7.4
    PM Increment: Effect Estimate: Odds
    ratios were less than 1.0 at all lags (0,1,
    2, 3)forPM25.
    No consistent association between any
    of the air pollutants and implantable
    cardioverter defibrillators discharges.
    Notes: Same study as Vedal et al.
    (2004, 0556301, except Rich (2004)
    used data from a shorter time period so
    as to estimate relative odds of ICD
    discharge associated with acute
    increases in more pollutants than Vedal
    (2004, 0556301.
    December 2009
                                     E-56
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Rich et al. (2008,1569101
    
    Period of Study: NR
    
    Location: New Jersey
    Outcome: Pulmonary Artery and Right
    Ventricular Pressures
    
    Age Groups: 25-68
    
    Study Design: Panel
    
    N: 11 subjects
    
    Statistical Analyses: Repeated
    Measures
    
    Covariates: Long-term trends, calendar
    month, weekday, apparent temperature
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered :0-6d
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD): NR
    
    Monitoring Stations: NR
    
    Copollutant: NR
    
    Co-pollutant Correlation: N/A
    PM Increment: 11.62|jg/m
    
    Change (Lower Cl, Upper Cl), p-value:
    
    ePAD:0.19(0.05, 0.33), 0.01
    
    RV diastolic pressure: 0.23 (0.11, 0.34),
    <0.001
    
    RV systolic pressure: 0.12 (-0.07, 0.31),
    0.23
    
    MPAP: 0.12 (-0.05, 0.28),  0.16/
    Reference: Riediker et al. (2004,
    0912611
    
    Period of Study: Fall 2001
    
    Location: Wake County, North Carolina
    Outcome: Heart rate variability
    (measured 10 h after shift): mean cycle
    length of normal R-R intervals (MCL),
    the standard deviation of normal R-R
    intervals (SDNN), and percentage of
    normal R-R interval differences greater
    than 50 msec  (PNN50), low frequency
    (0.04-0.15Hz), high frequency (0.15-
    0.40Hz), the ratio of low to high
    frequency.
    
    Blood analysis (measured 16 h after
    shift): Uric acid, blood urea nitrogen,
    gamma glutamyl transpeptidase, white
    blood cell count, red blood cell count,
    hematocrit,  hemoglobin, mean red blood
    cell volume (MCV), neutronphils (count
    and %), lymphocytes (count and %), C-
    reactive protein, plasminogen,
    plasminogen activator inhibitor type  1,
    von Willebrand factor (vWF),  endo-
    vthzelin-1, protein C, and interleukin-6
    
    Age Groups:  23-30 yr
    
    Study Design: Panel
    
    N: 9 healthy male troopers, repeated
    measures (36  person-days)
    
    Statistical Analyses: Mixed effects
    regression models (principal factor
    analysis for classification of exposure)
    
    Covariates: Potential confounders:
    temperature, relative humidity, number
    of law-enforcement activities during the
    shift and the avg speed during the shift
    
    Controlling had no effect on effect esti-
    mates for "crustal" and "speed-change"
    factors
    
    However, confounder inclusion  in the
    "speed change" and blood urea nitrogen
    and vWF reduced the effect estimate
    and the Cl included zero
    
    Season: Only 1 season included
    
    Dose-response Investigated? No
    
    Statistical Package: S-Plus 6.1
    Pollutant: In-vehicle PM25 components
    identified with factor analysis (crustal
    material, wear of steel automotive
    components, gasoline combustion,
    speed-changing traffic with engine
    emissions and brake wear
    
    Averaging Time: Exposure assessed
    during 3 p.m. to 12a.m. work shifts
    
    Mean: PM25mass= 23.0 pg/m3
    
    Monitoring Stations: Per vehicle
    
    Copollutant (correlation): Correlation
    to PM25Mass
    Benzene: r = 0.50
    Aldehydes: r = 0.34
    CO: r = 0.52
    Aluminum: r = 0.58
    Silicon: r = 0.66
    Sulfur: r = 0.58
    Calcium: r = 0.37
    Titanium: r = 0.41
    Chromium: r = 0.51
    Iron: r = 0.71
    Copper: r = 0.16
    Selenium: r = 0.38
    Tungsten: r = 0.37
    PM2.Lightscatter:r = 0.71
    PM Increment: 1 SD change in source
    factor
    
    Effect Estimate: % change in the health
    outcome per 1 SD change in the "speed
    change" factor
    
    MCL: 7%
    HRV: 16%
    supraventricular ectopic beats: 39%
    % Neutrophils: 7%
    % lymphocytes:-10%
    red blood cell volume MCV:  1%
    vWF: 9%
    blood urea nitrogen: 7%
    protein C:-11%
    % change in the health outcome per 1
    SD change  in the "crustal" factor
    MCL: 3% serum uric acid
    concentrations: 5%
    
    Note: Results (including CIs) are
    reported in figures 2 & 3.
    December 2009
                                    E-57
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Riojas-Rodriguez et al.
    (2006, 1569131
    Outcome: Heart rate variability (5-
    minute periods)
    Period of Study: Dec 2001 -Apr 2002    Study Design: Panel study
    
    Location: Mexico City metropolitan area N: 30 patients from the outpatient clinic
                                        of the National Institute of Cardiology of
                                        Mexico, where each subject had existing
                                        ischemic heart disease.
    
                                        Statistical Analysis: Mixed models
    Pollutant: PM25 (nephelometry)
    
    Averaging Time: 5 min
    
    Mean (SD), Range:
    46.8 pg/rri (SD= 1.82)
    
    Range: 0-483 pg/m3
    
    Copollutant: CO
    PM Increment: 10 pg/m
    
    Effect Estimate: Each 20 pg/m3
    increase in 5 min PM25 was associated
    with a: -0.008 decrease in the
    ln(HF)(95%CI: -0.015, 0.0004
    
    Notes: Population of subjects with
    known ischemic heart disease (25 men
    and 5 women who had at least 1 prior Ml
    [not in last 6 mo])
    
    Each 10 pg/m3 increase in 5-min mean
    PM25 was associated with non-
    significantly decreased HF, and  with
    similar, but smaller changes in LF and
    VLF
    Reference: Romieu et al. (2005,
    0862971
    Period of Study: 2000-2001
    
    Location: Mexico City, Mexico
    Outcome: Heart rate variability (HF, LF,   Pollutant: PM25
    VLF, PNN50, SDNN, r-MSSD)
                                         Averaging Time: 24 h
    Age Groups: >60 yr of age
     a       K      *    a               Copollutant: 03, N02, S02, PM1(
    Study Design: Double blind randomized
    controlled trial
    
    N: 50 elderly residents of a Mexico City
    nursing home
                                         PM Increment: 8 pg/m
    
                                         Effect Estimate: In the group receiving
                                         the fish oil supplement, each 8 pg/m3
                                         change in 24-h mean total exposure
                                         PM25 was associated with a: a) 54%
                                         reduction (95% Cl: -72% to -24%) in HF
                                         (log transformed) in the pre-
                                         supplementation phase
    
                                         b) 7% reduction (95% Cl: -20%, 7%) in
                                         the supplementation phase.
    
                                         Changes in other HRV parameters were
                                         also smaller in the supplementation
                                         phase. In the group receiving soy oil
                                         supplementation, the % reduction in HF
                                         was also smaller in the supplementation
                                         phase, but the differences were smaller
                                         and not statistically significant.
    
                                         Notes: Study of the effect of omega-3-
                                         fatty acid supplementation (2 g/day of
                                         fish oil vs.. 2 g/day of soy oil) to mitigate
                                         the effect of ambient PM25 on HRV.
                                         Subjects had no cardiac arrhythmias,
                                         cardiac pacemakers, allergies to omega-
                                         3 fatty acids or fish, treatment with  oral
                                         anticoagulants, or history of bleeding
                                         diathesis.  PM25 was measured and
                                         estimated indoors, outdoors, and with
                                         regards to total exposure (the same as
                                         Holguin et al.  (2003)).
    December 2009
                                    E-58
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Romieu et al. (2008,
    1569221
    Period of Study: Sep 2001-Apr 2002
    
    Location: Mexico City, Mexico
    Outcome: Copper/zinc superoxide
    dismutase activity (Cu/Zn SOD)
    
    Lipoperoxidation (LPO)
    
    Reduced glutathione (GSH)
    
    Age Groups: 60-96 yr
    
    Study Design: Intervention (randomly
    assigned fish oil or soy oil)
    
    N: 52 participants
    
    Statistical Analyses: Linear mixed
    models
    
    Covariates: Time
    
    Dose-response Investigated?
    Assessed possible nonlinearity using
    generalized additive mixed models with
    p-splines
    
    Statistical Package: STATAv8.2 and
    SASv9.1
    Pollutant: PM25 (indoor)
    
    Averaging Time: 24 h (same day)
    
    Mean (SD): 38.7 (14.7)
    
    Percentiles:
    25th: 30.62
    50th: 35.11
    75th: 41.10
    
    Range (Min, Max):  14.8, 70.9
    
    Monitoring Stations: Indoor measured
    inside nursing home
    
    Copollutant: 0;
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Regression coefficient (SE
    
    p-value):
    Cu/Zn SOD: -0.05 (0.02
    0.001)
    LPO (square root transformed): 0.08
    (0.09
    0.381)
    GSH (log-transformed
    quadratic term for PM): -0.05 (0.01
    0.002)
    
    Regression coefficient (SE
    
    p-value) by supplementation groups
    (same transformations as above): Cu/Zn
    SOD
    
    Soy Oil: -0.06 (0.02, O.001)
    
    Fish Oil:* 0.04 (0.02, 0.009)
    
    LPO
    Soy Oil:-0.02 (0.14, 0.904)
    Fish Oil: *0.16 (0.07, 0.024)
    
    GSH
    Soy Oil:-0.03 (0.04, 0.406)
    Fish Oil:-0.09 (0.04, 0.017)
    
    'Quadratic term for PM
    Reference: Ruckerl et al. (2007,
    1569311
    Outcome: lnterleukin-6 (IL-6),
    fibrinogen, C-reactive protein (CRP)
    Period of Study: May 2003-Jul 2004     Age Groups: 35-80 yr
    Location:
    Athens, Augsburg, Barcelona, Helsinki,
    Rome, and Stockholm
    Study Design: Repeated measures /
    longitudinal
    
    N: 1003 Ml survivors
    
    Statistical Analyses: Mixed-effect
    models
    
    Covariates: City-specific confounders
    (age, sex,  BMI)
    
    Long-term time trend and apparent
    temperature
    
    RH, time of day, day of week included if
    adjustment improved model fit
    
    Season: Long-term time trend
    
    Dose-response Investigated? Used p-
    splines to allow for nonparametric
    exposure-response functions
    
    Statistical Package: SASv91
    Pollutant: PM25
    
    Averaging Time: Hourly and 24-h (lag
    0-4, mean of lags 0-4, mean of lags 0-1,
    mean of lags 2-3, means of lags 0-3)
    
    Mean (SD): Presented by city only
    
    Monitoring Stations: Central
    monitoring sites in each city
    
    Copollutant:
    S02
    03
    NO
    N02
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change in mean blood markers per
    increase in IQR of air pollutant.
    
    IL-6
    Lag (IQR): % change in GM (95%CI)
    Lag 0(11.0): 0.46 (-0.89, 1.83)
                                                                                                                  Lag1 (11.0):-0.39
                                                                                                                  Lag 2 (11.0):-0.23
                     -1.69,0.93)
                     -1.53, 1.07)
                                                                                                                  5-day avg (8.6): 0.05 (-1.37,1.50)
    
                                                                                                                  Fibrinogen
                                                                                                                  Lag (IQR): % change in AM (95%CI)
                                                                                                                  Lag 0(11.0): 0.05 (-0.48, 0.58
                                                                                                                  Lag 1(11.0): 0.17 (-0.35, 0.69
                                                                                                                  Lag 2 (11.0): 0.20 (-0.32, 0.71)
                                                                                                                  5-day avg (8.6): 0.38 (-0.21,  0.96)
    
                                                                                                                  CRP
                                                                                                                  Lag (IQR): % change in GM  (95%CI)
                                                                                                                  Lag 0(11.0): 0.11  (-1.95, 2.21)
                                                                                                                  Lag1 (11.0):-0.06 (-1.98,1.90)
                                                                                                                  Lag 2 (11.0): 0.11  (-1.80, 2.06)
                                                                                                                  5-day avg (8.6):-0.13 (-2.15,1.92)
    December 2009
                                    E-59
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ruckerl et al. (2006,
    0887541
    Period of Study: Oct 2000-Apr 2001
    
    Location: Erfurt, Germany
    Outcome: C-reactive protein (CRP)
    serum amyloid A (SAA)
    E-selectin
    von Willebrand Factor (vWF)
    intercellular adhesion molecule-1  (ICAM-
    1)
    fibrinogen
    Factor VII
    prothrombin fragment 1+2
    D-dimer
    
    Age Groups: 50+
    
    Study Design: Panel (12 repeated
    measures at 2-wk intervals)
    
    N: 57 male subjects with coronary
    disease
    
    Statistical Analyses: Fixed effects
    linear and logistic regression models
    
    Covariates: Models  adjusted for
    different factors based on health
    endpoint
    
    CRP: RH, temperature, trend, ID
    
    ICAM-1: temperature, trend, ID
    
    vWF: air pressure, RH,  temperature,
    trend, ID
    
    FVII: air pressure, RH, temperature,
    trend, ID, weekday
    
    Season: Time trend  as covariate
    
    Dose-response Investigated?
    Sensitivity analyses examined nonlinear
    exposure-response functions
    
    Statistical Package: SAS v8.2 and S-
    piusve.o
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD): 20.0 (15.0)
    
    Percentiles:
    25th: 9.7
    50th: 14.9
    75th: 26.1
    
    Range (Min, Max): 2.6, 83.7
    
    Monitoring Stations: 1 site
    
    Copollutant:
    UFPs
    AP
    PM25
    PM10
    OC
    EC
    N02
    CO
    PM Increment: IQR (16.4
    
    5-day avg: 12.2)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Effects of air pollution on blood markers
    presented as OR (95%CI) for an
    increase in the blood marker above the
    90th percentile per increase in IQR air
    pollutant.
    
    CRP
    
    Time before draw:0to 23 h:  1.1 (0.7,
    1.8)
    24-47 h: 1.5 (0.9, 2.5)
    48-71 h: 1.2 (0.8, 1.9)
    5-day mean: 1.4 (0.9, 2.3)
    
    ICAM-1
    
    Time before draw: 0-23 h: 0.7 (0.4, 0.9)
    24-47 h: 1.3 (0.8, 1.8
    48-71 h: 1.8 (1.2, 2.7
    5-day mean: 1.1 (0.8,1.5)
    
    Effects of air pollution on blood markers
    presented as % change from the
    mean/GM in the blood marker per
    increase in IQR air pollutant.
    
    vWF
    
    Time before draw: 0-23 h: 3.9 (-0.3, 8.1)
    24-47 h: 3.1 (-1.6, 7.8)
    48-71 h: 3.6 (-1.1, 8.3)
    5-day mean: 5.6 (0.5,10.8)
    
    FVII
    
    Time before draw: 0-23 h: -2.5 (-6.2 to
    1.4)
    24-47 h:-2.8 (-6.1 to 0.6)
    48-71 h:-2.3 (-5.0 to 0.6)
    5-day mean:-3.5 (-6.4 to-0.4)
    
    Note: Summary of results presented in
    figures. SAA results indicate increase in
    association with PM (not as strong and
    consistent as with CRP)
    
    No association observed between  E-
    selectin and PM
    
    An increase in prothrombin fragment
    1+2 was consistently observed,
    particularly with lag 4
    
    Fibrinogen results revealed few
    significant associations, potentially due
    to chance
    
    D-dimer results revealed null
    associations in linear and logistic
    analyses
    December 2009
                                     E-60
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ruckerl et al. (2006,
    0887541
    Period of Study: Oct 2000-Apr 2001
    
    Location: Erfurt, Germany
    Outcome: C-reactive protein (CRP)
    serum amyloid A (SAA)
    E-selectin
    von Willebrand Factor (vWF)
    intercellular adhesion molecule-1
    (ICAM-1)
    fibrinogen
    Factor VII
    prothrombin fragment 1+2
    D-dimer
    
    Age Groups: 50+ yr
    
    Study Design: Panel (12 repeated
    measures at 2-wk intervals)
    
    N: 57 male subjects with coronary
    disease
    
    Statistical Analyses: Fixed effects
    linear and logistic regression models
    
    Covariates: Models  adjusted for
    different factors based on health
    endpoint
    
    CRP: RH, temperature, trend, ID
    
    ICAM-1: temperature, trend, ID
    
    vWF: air pressure, RH,  temperature,
    trend, ID
    
    FVII: air pressure, RH, temperature,
    trend, ID, weekday
    
    Season: Time trend  as covariate
    
    Dose-response Investigated?
    Sensitivity analyses examined nonlinear
    exposure-response functions
    
    Statistical Package: SAS v8.2 and S-
    piusve.o
    Pollutant: EC
    
    Averaging Time: 24 h
    
    Mean (SD): 2.6 (2.4)
    
    Percentiles:
    25th: 1.0
    50th: 1.8
    75th: 3.2
    
    Range (Min, Max): 0.2,12.4
    
    Monitoring Stations: 1  site
    
    Copollutant:
    UFPs
    AP
    PM25
    PM10
    OC
    EC
    N02
    CO
    PM Increment: IQR (2.3
    
    5-day avg: 1.8)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Effects of air pollution on blood markers
    presented as OR (95%CI) for an
    increase in the blood marker above the
    90th percentile per increase in IQR air
    pollutant.
    
    CRP
    Time before draw: 0-23 h: 1.2 (0.7, 2.0)
    24-47 h: 1.3 (0.7, 2.4)
    48-71 h: 1.6 (0.9, 2.7)
    5-day mean: 1.2 (0.7, 2.1)
    
    ICAM-1
    
    Time before draw: 0-23 h: 1.0 (0.7,1.6)
    
    24-47 h: 2.6 (1.7, 3.8)
    
    48-71 h: 4.0 (2.5, 6.1)
    
    5-day mean: 2.2 (1.4, 3.3)
    
    Effects of air pollution on blood markers
    presented as % change from the
    mean/GM in the blood marker per
    increase in IQR air pollutant.
    
    vWF
    
    Time before draw: 0-23 h: 5.0 (0.0,10.1)
    
    24-47 h: 7.6 (1.4, 13.7)
    48-71 h:1.1 (-5.2,7.4)
    5-day mean: 5.7 (-0.5,12.0)
    
    FVII
    
    Time before draw: 0-23 h: -5.7 (-10.5 to -
    0.7)
    24-47 h:-6.9 (-11.2 to-2.3)
    48-71 h: -4.2 (-8.4, 0.2)
    5-day mean:-6.0(-10.5to-1.2)
    
    Note: Summary of results presented in
    figures. SAA results indicate increase in
    association with  PM (not as strong and
    consistent as with CRP)
    
    No association observed between
    E-selectin and PM
    
    An increase in prothrombin fragment
    1+2 was consistently observed,
    particularly with lag 4
    
    Fibrinogen results revealed few
    significant associations, potentially due
    to chance
    
    D-dimer results revealed null
    associations in linear and logistic
    analyses
    December 2009
                                     E-61
    

    -------
                Reference
            Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
    Reference: Ruckerl et al. (2006,
    0887541
    
    Period of Study:
    Oct 2000-Apr 2001
    
    Location: Erfurt, Germany
    Outcome (ICD9 and ICD10): C-reactive  Pollutant: OC
    protein (CRP)                         .      .   „
    Serum amyloid A (SAA)                 Averaging Time: 24 h
    
    v'onw'febrand Factor (vWF)            Mean (SD): 1.5(0.6)
    intercellular adhesion molecule-1 (ICAM-  percentiles:
    1)                                   25th: 1.1
    Fibrinogen                            50th: 1.4
    FactorVII                             75th: 1.8
    Prothrombin fragment 1+2
    D-dimer                              Range (Min, Max): 0.3, 3.4
                                         Age Groups: 50+ yr
    
                                         Study Design: Panel (12 repeated
                                         measures at 2-wk intervals)
    
                                         N: 57 male subjects with coronary
                                         disease
    
                                         Statistical Analyses: Fixed effects
                                         linear and logistic regression models
    
                                         Covariates: Models adjusted for
                                         different factors based on health
                                         endpoint
                                         CRP: RH, temperature, trend,  ID
                                         ICAM-1: temperature, trend, ID
                                         vWF: air pressure, RH,  temperature,
                                         trend, ID
                                         FVII: air pressure, RH, temperature,
                                         trend, ID, weekday
    
                                         Season: Time trend as covariate
    
                                         Dose-response Investigated?
                                         Sensitivity analyses examined nonlinear
                                         exposure-response functions
    
                                         Statistical Package: SAS v8.2 and S-
                                         piusve.o
                                         Monitoring Stations: 1 site
    
                                         Copollutant:
                                         UFPs
                                         AP
                                         PM25
                                         PM10
                                         OC
                                         EC
                                         N02
                                         CO
                                PM Increment: IQR (0.7
    
                                5-day avg: 0.5)
    
                                Effect Estimate [Lower Cl, Upper Cl]:
                                Effects of air pollution on blood markers
                                presented as OR (95%CI) for an
                                increase in the blood marker above the
                                90th percentile per increase in IQR air
                                pollutant.
    
                                CRP
                                Time before draw: 0-23 h: 1.2 (0.7,1.9)
                                24-47 h: 1.3 (0.8, 2.1)
                                48-71 h: 1.4 (0.8, 2.4)
                                5-day mean: 1.2(0.7,1.8)
    
                                ICAM-1
                                Time before draw: 0-23 h: 0.9 (0.6,1.3)
                                24-47 h: 2.0 (1.3, 3.2)
                                48-71 h: 3.0 (1.8, 4.8)
                                5-day mean: 1.3(0.8,2.0)
    
                                 Effects of air pollution on blood markers
                                presented as % change from the
                                mean/GM in the blood marker per
                                increase in IQR air pollutant.
    
                                vWF
                                Time before draw: 0-23 h: 5.5 (0.2,10.8)
                                24-47 h: 8.0 (2.1, 13.9)
                                48-71 h: 3.5 (-2.6, 9.6)
                                5-day mean: 7.4 (2.0,12.8)
    
                                FVII
                                Time before draw: 0-23 h: -6.1 (-10.6 to -
                                1.4)
                                24-47 h:-7.2 (-11.4 to-2.8)
                                48-71 h: -3.8 (-8.2, 0.9)
                                5-day mean:-5.6 (-9.8 to-1.1)
    
                                Note: Summary of results presented in
                                figures. SAA results indicate increase in
                                association with  PM (not as strong and
                                consistent as with CRP)
    
                                No association observed between  E-
                                selectin and PM
    
                                An increase in prothrombin fragment
                                1+2 was consistently observed,
                                particularly with lag 4
    
                                Fibrinogen results revealed few
                                significant associations, potentially due
                                to chance
    
                                D-dimer results revealed null
                                associations in linear and logistic
                                analyses
    December 2009
                                     E-62
    

    -------
    Reference
    Reference: Ruckerl et al. (2007,
    0913791
    Period of Study: Oct 2000-Apr 2001
    Location: Erfurt, Germany
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Soluble CD40 ligand
    (sCD40L), platelets, leukocytes,
    erythrocytes, hemoglobin
    Age Groups: 50+ yr
    
    Study Design: Panel (12 repeated
    measures at 2-wk intervals)
    N: 57 male subjects with coronary
    disease
    Statistical Analyses: Fixed effects
    linear regression models
    Covariates: Long-term time trend,
    weekday of the visit, temperature, RH,
    barometric pressure
    Season: Time trend as covariate
    
    Dose-response Investigated? No
    Concentrations1
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 20.0 (15.0)
    
    Percentiles:
    25th: 9.7
    50th: 14.9
    75th: 26.1
    Range (Min, Max): 2.6, 83.7
    Monitoring Stations: 1 site
    Co pollutants:
    UFPs
    AP
    PM
    r IVI2.5
    PM,o
    MO
    INW
    Effect Estimates (95% Cl)
    PM Increment: IQR (16.4
    5-day avg: 12.2)
    Effect Estimate [Lower Cl, Upper Cl]:
    Effects of air pollution on blood markers
    presented as % change from the
    mean/GM in the blood marker per
    increase in IQR air pollutant.
    SCD40L, % change GM (pg/mL)
    lagO' 1 5 (-4 0 73)
    Lag 1:0. 2 (-5. 4, 6.2)
    Lag2: -2.6 (-8.0, 3.1)
    Lag3: 0.5 (-3.9, 5.0)
    5-day mean: 0.2 (-5.4, 6.2)
    Platelets, % change mean (103/ul)
    LagO: -0.6 (-1.9, 0.7)
    Lag1: 0.1 (-1.3, 1.5)
    Lag2:0.5 -0.9, 1.9
    Lag3:0.2 -1.1,1.5
    (T j— i, «.._«. n A i A r\ A o\
                                        Statistical Package: SAS v8.2 and S-
                                        piusve.o
                                                                             5-day mean:-0.4 (-1.9,1.2)
    
                                                                             Leukocytes, % change in mean
                                                                             (103/ul)
                                                                             LagO:-1.6 (-3.2, 0.0)
                                                                             Lag 1:-0.4 (-2.2, 1.4)
                                                                             Lag2:-0.2  -2.1, 1.7
                                                                             Lag3: -0.8 (-2.4, 0.7
                                                                             5-day mean:-1.6 (-3.5, 0.3)
    
                                                                             Erythrocytes, % change mean (106/ul)
                                                                             LagO:-0.1 (-0.5,0.3)
                                                                             Lag 1:-0.3 (-0.7, 0.2
                                                                             Lag2: -0.4 (-0.8, 0.0
                                                                             Lag3:-0.2 (-0.5, 0.1)
                                                                             5-day mean: -0.4 (-0.8, 0.0)
    
                                                                             Hemoglobin, % change mean (g/dl)
                                                                             LagO: 0.0 (-0.6, 0.5)
                                                                             Lag 1:-0.2 (-0.8, 0.3)
                                                                             Lag2:-0.5  -1.1, 0.0
                                                                             Lag3: -0.2 (-0.7, 0.2
                                                                             5-day mean:-0.5 (-1.0, 0.1)
    Reference: Sarnat et al. (2006, 0904891  Outcome: Supraventricular ectopy
                                        (SVE) or ventricular ectopy (VE)
    Period of Study: Summer and fall 2000
    Location: Steubenville, OH
    N: 32 nonsmoking older adults
    
    Statistical Analysis: Logistic mixed
    effects regression
    
    Season: Summer and fall
    
    Dose-response Investigated? No
    Pollutant: PM25
    
    Averaging Time: 5 days
    
    Median (IQR): PM25: Median: 19.0
    |jg/m3
    
    IQr=10.0
    
    Sulfate: Median: 6.1. IQR: 4.2
    
    EC: Median: 0.9. IQR:  0.5
    
    Copollutants: 03, N02, S02
    PM Increment: IQR
    
    Effect Estimate: PM25: SVE: OR = 1.42
    (95% 01:0.99, 2.04)
    
    VE: OR =1.02 (95% Cl: 0.63-1.65)
    
    Sulfate: SVE: OR =1.70 (95% 01:1.12,
    2.57)
    
    VE: OR =1.08 (95% 01:0.65, 1.80)
    
    EC: SVE: OR = 1.15 (95% 01:0.73,
    1.81)
    
    VE: OR =1.00 (95% 01:0.57, 1.75)
    
    Notes: Longitudinal study of 32
    nonsmoking older adults who had ECG
    measurements made every week for 24
    wk. PM measured within 1 mile of
    subjects' residences, and central site
    pollutant measurements were also
    made.
    December 2009
                                    E-63
    

    -------
    Reference
    Reference: Schneider et al. (2008,
    1919851
    
    Period of Study: Nov 2004-Dec 2005
    Location: Chapel Hill, NC
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Endothelial Function
    Parameters
    
    Age Groups: 48-80 yr
    Study Design: Panel
    N: 22 diabetics
    
    Statistical Analyses: Mixed Models
    Covariates: Season, day of the week,
    temperature, relative humidity,
    barometric pressure
    Dose-response Investigated? No
    Statistical Package: SAS
    
    Lags Considered: 0-4 days; 5-day ma
    
    Concentrations1
    Pollutant: PM25
    
    Averaging Time: Daily
    Mean (SD): 13.6 (7.0)
    Min:2.0
    
    Max: 38.9
    Monitoring Stations: 2
    Copollutant: NR
    
    
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    
    Percent Change: (Lower Cl, Upper
    Cl), lag:
    cyr> AI
    rlvlU. I
    -1 7.3 (-34.6, 0.0, lag 0
    -4.4 (-24.6, 15.8, lag 1
    -18.6 (-44.8, 7.6), lag 2
    1.6 (-23.6, 26.9), lag 3
    18.4 (-3.5, 40.3), lag 4
    -19.4 (-62.6, 23.8), 5-day ma
    NTGMD:
    2.5 (-9.0, 13.9), lag 0
    -13.6 (-24.5, -2.6), lag 1*
    -10.2 (-23.5, 3.0), lag 2
    -8.0 (-22.4, 6.4), lag 3
    3.6 (-7.9, 15.0), lag 4
    -19.4 (-44.3, 5.5), 5-day ma
                                                                                                                 LAEI:
                                                                                                                 0.4 (-4.2, 5.0), lag 0
                                                                                                                 -0.3 (-6.0, 5.4), lag 1
                                                                                                                 2.5 (-4.3, 9.4), lag 2
                                                                                                                 -7.3 (-13.5, -1.1), Iag3*
                                                                                                                 -2.3 (-8.0, 3.3), lag 4
                                                                                                                 -4.6 (-15.3, 6.1), 5-day ma
                                                                                                                 SAEI:
                                                                                                                 -3.0 (-13.0, 7.0), lag 0
                                                                                                                 -17.0 (-27.5,  -6.4), Iag1**
                                                                                                                 -9.7 (-23.5, 4.2), lag 2
                                                                                                                 -15.1 (-29.3,-0.9)*, lag 3
                                                                                                                 -2.1 (-14.0, 9.7), lag 4
                                                                                                                 -25.4 (-45.4,  -5.3), 5-day ma*
    
                                                                                                                 SVR:
                                                                                                                 -1.6 (-3.7, 0.4), lagO
                                                                                                                 1.6 -0.9, 4.1), lag 1
                                                                                                                 3.5 0.5, 6.5), lag 2
                                                                                                                 2.4 (-0.5, 5.3), lag 3
                                                                                                                 " " 0.7, 5.6), lag 4*
                                                                                                                 4.5
                                                                                                                     -0.3, 9.2), 5-day ma
                                                                                                                 *p<0.05, **p<0.01
    
                                                                                                                 Notes: Percent change (95% Cl) per
                                                                                                                 10 pg/m3 PM25 by GSTM1 genotype
                                                                                                                 (Fig 3)
    Reference: Schwartz et al. (2005,
    0743171
    
    Period of Study: 12 wk during the
    summer of 1999
    
    Location: Boston, MA
    Outcome: Heart rate variability (HRV),
    (SDNN,
    
    r-MSSD, PNN50, LFHFR)
    
    Age Groups: 61-89 yr
    
    Study Design: Panel study
    
    N: 28 elderly subjects
    
    Statistical Analysis: Mixed models. To
    examine heterogeneity of effects,
    hierarchical modeling was used.
    
    Season: Summer
    
    Dose-response Investigated? No
    Pollutant: PM25
    
    Averaging Time: 1 h, 24 h
    
    Median: 24-h: 10 pg/m3
    
    Monitoring Stations: 1
    
    Copollutant: BC, 03, CO, S02, N02
    PM Increment: IQR (not given)
    
    Effect Estimate: 24 h: 2.6 ms decrease
    in SDNN (95% Cl: 0.8 to-6.0)
    
    10.1 ms decrease in r-MSSD (95% Cl: -
    2.8to-16.9).
    
    1 h: 3.4 ms decrease in SDNN (95% Cl:
    0.6to-7.3)
    
    7.4 ms decrease in r-MSSD (95% Cl:
    1.6to-15.5).
    
    Notes: Various log-transformed HRV
    parameters were measured  for 30
    minutes once a week. The random
    effects model indicated that the negative
    effect of BC on  HRV was not restricted
    to a few subjects.
    
    Same study population as Gold et al.
    (2005). Boston  Elders Study
    
    For each pollutant/averaging time,
    similarly sized changes were observed
    for PNN50 (%) and LFHFR.
    December 2009
                                    E-64
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Schwartz et al. (2005,
    0743171
    Period of Study: 12 wk during the
    summer of 1999
    Location: Boston, MA
    Outcome: Heart rate variability (HRV),
    (SDNN, r-MSSD, PNN50, LFHFR)
    Age Groups: 61 -89 yr
    Study Design: Panel study
    N: 28 elderly subjects
    Statistical Analysis: Mixed models. To
    examine heterogeneity of effects,
    hierarchical modeling was used.
    Season: Summer
    Dose-response Investigated? No
    Pollutant: BC
    Averaging Time: 24 h
    Median: 1.0|jg/m3
    Monitoring Stations: 1
    Copollutant: PM25, 03, CO, S02, N02
    PM Increment: IQR
    Effect Estimate: 5.1 ms decrease in
    SDNN (-1.5 to-8.6)
    10.1 ms decrease in r-MSSD (-2.4 to -
    17.2).
    Notes: Various log-transformed HRV
    parameters were measured for 30
    minutes once a week. The random
    effects model indicated that the negative
    effect of BC on HRV was not restricted
    to a few subjects. Same study
    population as Gold et al. (2005). Boston
    Elders Study. Subjects with a prior Ml
    experienced greater declines in BC
    associated HRV. For each
    pollutant/averaging time, similarly sized
    changes were observed for PNN50 (%)
    and LFHFR.
    Reference: Schwartz et al. (2005,
    0743171
    Period of Study: 2000
    Location: Boston, Massachusetts
    Outcome: HF (high frequency
    component of heart rate variability)
    Study Design: Cross-sectional
    N: 497 subjects
    Statistical Analysis: Linear regression,
    controlling for covariates
    Pollutant: PM25
    Averaging Time: 48 h
    Mean(SD):11.4|jg/m3(8.0)
    Copollutant: None
    PM Increment: 10 pg/m
    Effect Estimate: 34% decrease in HF
    (95% Cl: -9% to -52%) in subjects
    without the GSTM1 allele. In subjects
    with the allele, no effect was noted.
    Similar findings for obese subjects and
    those with high neutrophil counts.
    Notes: Study population: Normative
    Aging Study.
    Effects of PM2 5 appear to be mediated
    by ROS.
    Reference: Sorensen et al. (2005,
    0894281
    Period of Study: Nov 1999-Aug 2000
    Location: Copenhagen, Denmark
    Outcome: 7-Hydro-8-Oxo-2'-
    Deoxyguanosine (8-oxodG) (measured
    in lymphocytes and urine)
    Age Groups: 20-33 yr
    Study Design: Panel (repeated
    measures)
    N: 49 students living and studying in
    central Copenhagen
    50 students examined each season (66
    subjects total
    32 participated in each season
    total of 98 measurements)
    Statistical Analyses: Mixed models
    repeated measures
    Covariates: PM25, season, subject
    (random factor)
    Dose-response Investigated? No
    Statistical Package: SAS v8e
    Pollutant: PM25
    Averaging Time: 48 h
    Mean (SD): Fall: 20.7
    Summer: 12.6
    Percentiles: IQR Fall: 13.1-27.7
    IQR summer: 9.4-24.3
    Range (Min, Max): NR
    Monitoring Stations: NA (personal
    assessment)
    Copollutant (correlation):
    Spearman correlations with PM25 mass:
    chromium (r = 0.22)
    copper (r = 0.33)
    iron (r = 0.29)
    vanadium (p>0.5)
    nickel (p>0.5)
    platinum (p>0.5)
    PM Increment: see below
    Effect Estimate [Lower Cl, Upper Cl]:
    Association between 8-oxodG in
    lymphocytes and personal exposure to
    transition metals in PM2 5.
    % increase in 8-oxodG per increase in
    metal concentration indicated
    Vanadium: 1.9% per 1 pg/L (0.6, 3.3)
    Chromium: 2.2% per 1 pg/L (0.8, 3.5)
    Platinum: 6.1% perl ng/L(-0.6,13.2)
    Nickel: 0.8% per 10 pg/L (-2.1, 3.7)
    Copper:  -0.8% per 10 pg/L (-2.7,1.0)
    Iron: 0.6%  per 10 pg/L (-1.4, 2.6)
    Note: PM25 mass was independently
    associated with 8-oxodG in 5 of 6
    transition metal models  (p < 0.02 in
    models with vanadium, chromium,
    nickel, copper, and iron
    p = 0.07  in platinum model). No
    transition metals were associated with 8-
    oxodG measured in urine
    December 2009
                                    E-65
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Sorensen et al. (2003,
    0427001
    Period of Study: Nov 1999-Aug 2000
    Location: Copenhagen, Denmark
    Outcome: RBC count, hemoglobin,
    platelet count, fibrinogen, PLAAS (2-
    aminoadipic semialdehyde in plasma
    proteins), HBGGS (v-glutamyl
    semialdehyde in hemoglobin), HBAAS
    (2-aminoadipic semialdehyde in
    hemoglobin), MDA (malondialdehyde)
    Age Groups: 20-33 yr
    Study Design: Panel (repeated
    measures)
    N: 50 students living and studying in
    central Copenhagen
    50 students examined each season (68
    subjects total
    31 participated in each season
    total of 195 measurements)
    Statistical Analyses: Mixed model
    repeated-measures analysis
    Covariates: Season,  avg outdoor
    temperature,  and sex
    Season: Repeated measures 4 times
    (once per season)
    Dose-response Investigated? No
    Statistical Package:  SAS v8e
    Pollutant: PM25 (personal)
    Averaging Time: 48 h
    Median: 16.1 pg/m3
    Percentiles: Q25-Q75:10.0-24.5
    Copollutant:
    Urban background PM25
    Personal PM25
    PM Increment: 1 pg/m
    Effect Estimate [Lower Cl, Upper Cl]:
    Relationship between exposure and
    biomarkers
    Estimate (p-value): Platelet count (x
    106/g protein): 0.0008 (0.37)
    Fibrinogen (nmol/g protein): 0.0006
    (0.69)
    PLAAS (pmol/mg protein): 0.0016
    (0.061)
    HBGGS (pmol/mg protein): 0.0001
    (0.94)
    HBAAS (pmol/mg  protein): 0.0006 (0.64)
    Increase (96%CI) in biomarkers per 10
    ug/m3 increase in PM25
    RBC
    Men: 0% (-1.6,1.6)
    Vtomen: 2.3% (0.5, 4.1)
    Hemoglobin
    Men: 0.0% (-1.7,1.5)
    Vtomen: 2.6% (0.8, 4.5)
    Reference: Sorensen et al. (2003,
    0427001
    Period of Study: Nov 1999-Aug 2000
    Location: Copenhagen, Denmark
    Outcome: RBC count, hemoglobin,
    platelet count, fibrinogen, PLAAS (2-
    aminoadipic semialdehyde in plasma
    proteins), HBGGS (Y-glutamyl semi-
    aldehyde in hemoglobin), HBAAS (2-
    aminoadipic semialdehyde in
    hemoglobin), MDA (malondialdehyde)
    Age Groups: 20-33 yr
    Study Design: Panel (repeated
    measures)
    N: 50 students living and studying in
    central Copenhagen
    50 students examined each season (68
    subjects total
    31 participated in each season
    total of 195 measurements)
    Statistical Analyses: Mixed model
    repeated-measures analysis
    Covariates: Season,  avg outdoor
    temperature,  and sex
    Season: Repeated measures 4 times
    (once per season)
    Dose-response Investigated? No
    Statistical Package:  SAS v8e
    Pollutant: Personal exposure to black
    carbon (10-6/m)
    Averaging Time: 48 h
    Median: 8.1
    Percentiles: Q25-Q75: 5.0-13.2
    Copollutant:
    Urban background PM25
    Personal PM25
    PM Increment: 10-6/m
    Effect Estimate [Lower Cl, Upper Cl]:
    Relationship between exposure and
    biomarkers
    Estimate (p-value): RBC count (x 109/g
    protein): 0.0003 (0.75)
    Hemoglobin (pmol/g protein): 0.0004
    (0.65)
    Platelet count (x 106/g protein): 0.0009
    (0.51)
    Fibrinogen (nmol/g protein): -0.0027
    (0.29)
    PLAAS (pmol/mg protein): 0.0041
    (0.0009)
    HBGGS (pmol/mg protein): 0.0024
    (0.25)
    HBAAS (pmol/mg  protein): 0.0022 (0.20)
    MDA (pmol/mg protein): 0.0018 (0.30)
    December 2009
                                    E-66
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Sorensen et al. (2003,
    0427001
    Period of Study: Nov 1999-Aug 2000
    Location: Copenhagen, Denmark
    Outcome: RBC count, hemoglobin,
    platelet count, fibrinogen, PLAAS (2-
    aminoadipic semialdehyde in plasma
    proteins), HBGGS (v-glutamyl
    semialdehyde in hemoglobin), HBAAS
    (2-aminoadipic semialdehyde in
    hemoglobin), MDA (malondialdehyde)
    Age Groups: 20-33 yr
    Study Design: Panel (repeated
    measures)
    N: 50 students living and studying in
    central Copenhagen
    50 students examined each season (68
    subjects total
    31 participated in each season
    total of 195 measurements)
    Statistical Analyses: Mixed model
    repeated-measures analysis
    Covariates: Season, avg outdoor
    temperature,  and sex
    Season: Repeated measures 4 times
    (once per season)
    Dose-response Investigated? No
    Statistical Package: SAS v8e
    Pollutant: PM25 (urban background
    concentration)
    Averaging Time: 48 h
    Median: 9.2 pg/m3
    Percentiles: Q25-Q75: 5.3-14.8
    Copollutant:
    Urban background PM25
    Personal carbon black
    PM Increment: 1 pg/m
    Effect Estimate [Lower Cl, Upper Cl]:
    Relationship between exposure and
    biomarkers
    Estimate (p-value): RBC count (x 109/g
    protein): 0.0008 (0.36)
    Hemoglobin (pmol/g protein): 0.0005
    (0.53)
    Platelet count (x 106/g protein): -0.0008
    (0.49)
    Fibrinogen (nmol/g protein): 0.0004
    (0.84)
    PLAAS (pmol/mg protein): 0.0004 (0.76)
    HBGGS (pmol/mg protein): -0.0020
    (0.39)
    HBAAS (pmol/mg protein): -0.0021
    (0.29)
    MDA (pmol/mg protein): 0.0012 (0.52)
    Reference: Sullivan et al. (2007,
    1000831
    Period of Study: Feb 2000-Mar 2002
    Location: Seattle, Washington, USA
    Outcome: Blood CRP, fibrinogen, D-
    dimer
    Age Groups: >55 yr of age
    Study Design: Panel study
    N: 47 elderly subjects
    Pollutant: PM25
    Averaging Time: 24 h
    Median (IQR): 7.7 pg/m3 (6.4)
    Monitoring Stations: 1
    Copollutant: Indoor PM25
    PM Increment: 10 pg/m
    Effect Estimate: Among those with
    CVD, PM251 day earlier: CRP: 1.25
    (95% 0:0.97,1.58)
    Fibrinogen: 1.01 (95% Cl: 0.97,1.05)
    D-dimer: 1.04 (95% Cl: 0.93,1.15)
    With COPD: CRP: 0.69 (95% Cl: 0.34,
    1.42)
    Fibrinogen: 1.05 (95% Cl: 0.97,1.13)
    D-dimer: 1.10 (95% Cl: 0.95,1.28)
    Healthy: CRP: 1.01 (95% Cl: 0.85,1.19)
    Fibrinogen: 0.88 (95% Cl: 0.81, 0.95)
    D-dimer: 1.10 (95% Cl: 0.75,1.58)
    Notes: Out of 47 subjects, n = 23 with
    CVD and n = 24 (n = 16 COPD and 8
    healthy) without CVD. Blood markers
    were measured on 2-3 morning over a
    5-10 day period, and outdoor PM25 was
    measured at a central monitoring site.
    These findings are not consistent with
    and effect of fine PM on markers of
    inflammation  and thrombosis in the
    elderly.
    December 2009
                                    E-67
    

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               Reference                    Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
    Reference: Sullivan et al. (2005,         Outcome: Heart rate variability (H, LF,    Pollutant: PM25                     PM Increment: 10 pg/m3
    1094181                            HF, r-MSSD, SDNN)                   .      .   „     „ t                 ™  .-.-.„,
                                                                          Averaging Time: 1 h                 Effect Estimate: 1 h:
    Period of Study: Feb 2000-Mar 2002    Study Design: Panel study
                 y                          y    a           >             Median (IQR): 10.7 (7.6)              With CVD: HF: (3% increase, 95% Cl:
    Location: Seattle, Washington, USA     N: 34 elderly subjects with (n = 21) and                                     -19, 32)
                                       without (n = 13) CVD                  Copollutant: CO, N02
                                             1      '                                                         Wthout CVD: H F(5% decrease, 95% Cl:
                                       Statistical Analysis: Linear mixed                                         -34, 36)
                                       effects regression                                                                        .
                                                                                                            Similarly, no association was found for
                                                                                                            4-h or 24-h mean PM25 concentrations.
    
                                                                                                            Notes: 285 daily 20 min HRV measures
                                                                                                            were made in the homes of study
                                                                                                            subjects over a 10-day period.
    December 2009                                                 E-68
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Sullivan et al. (2005,
    1094181
    
    Period of Study: Feb 2000-Mar 2002
    
    Location: Seattle area, WA
    Outcome (ICD9 and ICD10): High-
    sensitivity C-reactive protein (hs-CRP)
    
    fibrinogen
    
    D-dimer
    
    Endothelin-1 (ET-1)
    
    lnterleukin-6 (IL-6
    
    lnterleukin-6 receptor (IL-6r)
    
    Tumor necrosis factor-a (TNF-8- a)
    
    Tumor necrosis factor-receptors (p55,
    p75)
    
    Monocyte chemoattractant protein-1
    (MCP-1)
    
    Age Groups: > 55 yr
    
    Study Design: Panel (repeated
    measures)
    
    N: 47 participants with (23) and without
    (10COPD and 8 healthy) CVD
    
    Statistical Analyses: Mixed models
    
    Covariates: Age, gender, medication
    use, meteorological variables
    (temperature and RH)
    
    Dose-response Investigated? No
    
    Statistical Package: SAS v8.02
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    (0-day and 1-day lags)
    
    Mean (SD): NR
    Percentiles: For all subject-days:
    25th: 5.2
    50th: 7.7
    75th: 11.5
    90th: 19.9
    Range (Min, Max): 1.3, 33.9
    
    Monitoring Stations: NA, measured at
    participant's residence
    
    Copollutant: None
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Multiplicative change in mean outcome
    associated with 10 pg/m3 increase in PM
    
    Among those with different disease
    status.
    
    CRP Fold-rise (96%CI)
    CV
    0-day lag: 1.21 (0.86,1.70)
    CV
    1-day lag: 1.25 (0.97,1.58);
    COPD
    0-day lag: 0.93 (0.48,1.80)
    COPD
    1-day lag: 0.69 (0.33,1.46)
    Healthy
    0-day lag: 0.98 (0.88,1.08)
    Healthy
    1-day lag: 1.01 (0.841.21)
    Fibrinogen Fold-rise (96%CI)
    CV
    0-day lag: 1.02 (0.98,1.06)
    CV
    1-day lag: 1.0 (0.97,1.03);
    COPD
    0-day lag: 1.0 (0.91,1.09)
    COPD
    1-day lag: 1.08 (0.99,1.17)
    Healthy
    0-day lag: 0.94 (0.87,1.01)
    Healthy
    1-day lag: 0.99 (0.88,1.17)
    
    D-dimer Fold-rise (96%CI)
    CV
    0-day lag: 1.02 (0.88,1.17)
    CV
    1-day lag: 1.03 (0.93,1.15);
    COPD
    0-day lag: 1.04 (0.93,1.16)
    COPD
    1-day lag: 1.09 (0.94,1.27)
    Healthy
    0-day lag: 0.95 (0.79,1.14)
    Healthy
    1-day lag: 0.97 (0.71,1.31)
    Among those with cardiovascular
    disease
    
    MCP-1  Fold-rise (96%CI)
    
    0-day lag: 1.3 (1.1,1.7)
    1-day lag: 1.0 (0.9,1.3)
    
    ET-1 Fold-rise (96%CI)
    
    0-day lag: 1.1 (0.8,1.2)
    1-day lag: 1.1 (0.9,1.2)
    
    Note: TNF-a and IL-6 measures were
    below the limit of detection  of assays
    Reference: Timonen et al. (2006,
    0887471
    Period of Study: 1998-1999
    
    Location Amsterdam, Netherlands
    
    Erfurt, Germany
    
    Helsinki, Finland
    Outcome: Heart variability (HRV)
    measurements: [LF, HF, LFHFR,  Nl\
    interval, SDNN, r-MSSD]
    
    Study Design: Panel study
    
    N:131 elderly subjects with stable
    coronary heart disease
    
    Statistical Analysis: Linear mixed
    models
    Pollutant: PM25
    
    Means:
    
    Amsterdam: 20.0
    
    Erfurt: 23.3
    
    Helsinki: 12.7
    
    Copollutant: N02, CO
    PM Increment: 10 pg/m
    
    Effect Estimate: SDNN
    
    -0.33ms (95% Cl:-1.05, 0.38)
    
    HF: -0.3% (95% Cl: -10.6, 5.4)
    
    LFHFR:-1.4 (95% Cl:-5.9, 8.7)
    
    Notes: Followed for 6 mo with biweekly
    clinic visits
    
    2-day lag. ULTRA Study
    December 2009
                                    E-69
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Vallejo et al. (2006,1570811  Outcome: Heart rate variability
    „  •  .,  «~ .,   ,    ,    .vw,         measures (SDNN, pNNSO)
    Period of Study: Apr-Aug 2002
    Location: Mexico City metropolitan area
    Age Groups: Mean age 27 yr
    
    Study Design: Panel study
    
    N: 40 young healthy participants (non-
    smokers, no meds or history of CVD,
    respiratory,  neurological, or endocrine
    disease)
    
    Statistical Analysis: Linear mixed
    effects models
    Pollutant: PM25
    
    (pDR nephelometric method-DataRAM)
    
    Copollutant: None
    PM Increment: 30 pg/m
    Effect Estimate: pNNSO:
    0 h lag:-0.01%  (95% Cl:-0.03, 0.01)
    1  h:-0.01% (95% Cl:-0.04, 0.02)
    2 h: -0.05% (95% Cl: -0.09, 0.00)
    3 h:-0.07% (95% Cl:-0.13 to-0.02)
    4 h:-0.08% (95% Cl:-0.14 to-0.01)
    5 h:-0.06% (95% Cl:-0.13, 0.02)
    6 h:-0.05% (95% Cl:-0.13, 0.04)
    SDNN:
    Oh: 0.00% (95%Cl:0.00, 0.01)
                                                                                                                   1 h: 0.00%
                                                                                                                   2 h: 0.00%
                                                    95% Cl:-0.01, 0.01
                                                    95% Cl:-0.02, 0.01
                                                                                                                   3 h:-0.01% (95% Cl:-0.02, 0.00)
                                                                                                                   4 h:-0.01% (95% Cl:-0.02, 0.01)
                                                                                                                   5 h:-0.01% (95% Cl:-0.02, 0.01)
                                                                                                                   6 h: 0.00% (95% Cl:-0.02, 0.02)
                                                                                                                   Notes: Subjects underwent 13 h of ECG
                                                                                                                   monitoring and personal PM25
                                                                                                                   measurement. HRV measures were
                                                                                                                   regressed against different lags of PM2 5
                                                                                                                   concentration.
    Reference: Van Hee et al. (2009,
    1921101
    
    Period of Study: Jul 2000-Aug 2002
    
    Location: Baltimore, Maryland
    
    Chicago, Illinois
    
    Winston-Salem, North Carolina
    
    St. Paul
    
    Minnesota
    
    New York, New York
    
    Los Angeles, California
    Outcome: Left Ventricular Mass Index
    and Ejection Fraction
    
    Age Groups: 45-84 yr
    
    Study Design: Cross-sectional
    
    N: 3,827 participants
    
    Statistical Analyses: Linear Regression
    Models
    
    Covariates: Age, race, income, sex,
    education, medication use, LDL, HDL,
    physical activity, alcohol consumption,
    smoking, diabetes, systolic BP, diastolic
    BP
    
    Dose-response Investigated? No
    
    Statistical Package: Stata
    
    Lags Considered: NR
    Pollutant: PM25
    
    Averaging Time: NR
    
    Mean (SD): Fig only
    
    Monitoring Stations: N/A
    
    Interpolation used
    
    Copollutant: NR
    
    Co-pollutant Correlation: N/A
    PM Increment: 10 pg/m
    
    Difference (Lower Cl, Upper Cl), p-
    value:
    
    Left Ventricular Mass Index
    
    Unadjusted: -6.0 (-7.8, -4.2), O.0001
    
    All covariates except center, BP: -6.1 (-
    7.8, -4.4), O.0001
    
    All covariates except BP: 3.7 (-6.0,
    13.4), 0.46
    
    Full model: 4.6 (-4.7,13.9), 0.33
    
    Full model plus center/race interaction:
    3.8 (-6.1,13.7), 0.45
    
    Left Ventricular Ejection Fraction
    
    Unadjusted: 3.0 (2.2, 3.8),  <0.0001
    
    All covariates except center, BP: 1.4
    (0.5, 2.2), 0.001
    
    All covariates except BP: -1.1 (-5.8, 3.7),
    0.66
    
    Full model:-1.3 (-6.0, 3.5), 0.60
    
    Full model plus center/race interaction: -
    3.0 (-8.0, 2.0), 0.24
    Reference: Wellenius et al. (2007,
    0928301
    Outcome: Circulating levels of B-type
    natriuretic peptide (BNP
    Period of Study: Feb 2002-Mar 2003    Measured in whole blood at 0, 6,12 wk)
    
    Location: Boston, Massachusetts, USA  Study Design: Panel study
    
                                         N: 28 subjects (each with chronic stable
                                         HF and impaired systolic function)
    
                                         Statistical Analysis: Linear mixed
                                         effects models
    Pollutant: PM25
    
    Copollutant: N02, S02, 03, CO, BC
    PM Increment: 10 pg/m
    
    Effect Estimate: Same day PM25: 0.8%
    increase in BNP (95% Cl: -16.4, 21.5)
    
    Notes: The study found no association
    between any pollutant and measures of
    BNP at any lag. Further, the within
    subject coefficient of variation was large
    suggesting the magnitude of effected air
    pollutant health effects are small in
    relation to within subject variability in
    BNP.
    December 2009
                                     E-70
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Wellenius et al. (2007,
    0928301
    Period of Study: Feb 2002-Mar 2003
    Location: Boston, Massachusetts
    Outcome (ICD9 and ICD10): B-type
    natriuretic peptide (BMP) (natural-log
    transformed)
    Age Groups: 33-88 yr
    Study Design: Panel (blood collected at
    0, 6, and12wk)
    N: 28 patients with chronic stable heart
    failure and impaired  systolic function
    Statistical Analyses: Linear mixed-
    effects models
    Covariates: Temperature, dew point,
    mean dew point over the past 3 days,
    calendar month of blood draw, mea-
    surement occasion, treatment
    assignment, measurement occasion by
    treatment assignment interaction
    Season: Adjusted for calendar month
    Dose-response Investigated? No
    Statistical Package: SASv91
    Pollutant: PM25
    Averaging Time: Daily (assessed lags
    of 0-3 days)
    Mean (SD): 10.9 (8.4)
    Percentiles: 50th: 8.0 pg/m3
    Range (Min, Max): 07-50.9 pg/m3
    Monitoring Stations: 1 monitor
    Copollutant (correlation):
    CO (r = 0.35)
    N02(r = 0.31)
    S02(r = 0.18)
    03(r = 0.35)
    BC(r = 0.68)
    PM Increment: IQr = 8.1 pg/m
    Effect Estimate [Lower Cl, Upper Cl]:
    % change in BMP per IQR increase in
    PM25
    LagO: 1.5 (-18.7,19.2)
    Lag1:2.1 (-20.0,30.3)
    Lag2:1.3 (12.3,17.1)
    Lag3: 5.6 (-16.8, 34.0)
    Note: No significant associations
    observed between any pollutant and
    BMP levels at any lags (presented in
    Fig 2)
    Reference: Wheeler et al. (2006,
    0884531
    Period of Study: Fall 1999 and spring
    2000
    Location: Atlanta, GA
    Outcome: Heart rate variability
    Age Groups: 49-76 yr
    N: 18 subjects with COPD and 12
    subjects with a recent Ml
    Statistical Analysis: Linear-mixed
    effect model
    Season: Fall and spring
    Pollutant: PM25
    Averaging Time:
    1 h
    4h
    24 h
    Mean: 24-h: 17.8 pg/m3
    Copollutant: 03, CO, S02, N02
    PM Increment: 11.65 pg/m3 (IQR) in 4 h
    PM25
    Effect Estimate: Among COPD
    patients: 8.3% increase in SDNN (95%
    0:1.7,15.3)
    Among Ml patients: 2.9% decrease in
    SDNN (95% Cl:-7.8, 2.3)
    Results for 1-h and 24-h averaging times
    were similar.
    Notes: Data was collected on 7 days in
    the fall of 1999 or spring of 2000.
    Effects were modified by medication
    use, baseline pulmonary function, and
    health status.
    December 2009
                                    E-71
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Yeatts et al. (2007, 0912661
    Period of Study: 12-wk period b/t
    Sep 2003-Jul 2004
    Location: Chapel  Hill, NC
    Outcome: Heart Rate Variability
    Age Groups: 21-50 yr
    Study Design: Panel
    N: 12 asthmatics
    Statistical Analyses: Linear Mixed
    Model
    Covariates: Temperature, humidity,
    pressure
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: 1 day
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 12.5 (6.0)
    Min:0.6
    Max: 37.1
    Monitoring Stations: 1
    Copollutant: PM10.2.5, PM10
    Co-pollutant Correlation:
    PMio-25 = 0.46*
    PM10 = NR
    *p < 0.01
    PM Increment: 1 pg/m
    Beta, SE (Lower Cl, Upper Cl), p-
    value:
    HRV
    Max Heart Rate: 0.40, 0.43 (-0.45,1.24),
    0.36
    ASDNN5: -0.07, 0.15 (-0.37, 0.22), 0.63
    SDANN5:1.66, 0.65 (0.39, 2.93), 0.02
    SDNN24HR(mesc): 1.16, 0.58(0.02,
    2.29), 0.06
    rMSSD:0.53, 0.20(0.14, 0.91), 0.01
    pNN50_24hr:-0.06, 0.11 (-0.27, 0.15),
    0.58
    pNN50_7min: 0.47, 0.42 (-0.35,  1.29),
    0.27
    Low-frequency power: -0.23, 0.14 (-0.51,
    0.05), 0.11
    Percent low frequency: -0.78, 0.41 (-
    1.59, 0.03), 0.07
    High-frequency power: 0.14, 0.07 (-0.01,
    0.28), 0.07
    Percent high frequency: 0.64, 0.36 (-
    0.07, 1.34), 0.09
    Blood Lipids
    Triglycerides: -0.63, 0.84 (-2.29,1.02),
    0.46
    VLDL:-0.17, 0.22 (-0.61, 0.26), 0.44
    Total cholesterol: -0.06, 0.22 (-0.49,
    0.36), 0.77
    Hematologic Factor
    Circulating eosinophils: -0.02, 0.00 (-
    0.02, -0.02),  0.27
    Platelets:-0.01, 0.45 (-0.88, 0.86), 0.98
    Circulating Proteins
    Plasminogen: 0.00, 0.00 (-0.01, 0.00),
    0.82
    Fibrenogen: 0.00, 0.01 (-0.01,0.02),
    0.59
    Von Willibrand factor: -0.31, 0.29 (-0.87,
    0.25), 0.28
    Factor VII:-0.65, 0.33 (-1.29, -0.01),
    0.05
    December 2009
                                     E-72
    

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                 Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95%  Cl)
    Reference: Yue et al. (2007, 0979681
    
    Period of Study: Oct 2000-Apr 2001
    
    Location: Erfurt, Germany
    Outcome: QT interval and T-wave
    amplitude for ECG recordings, and vWF,
    CRP from blood samples
    
    Study Design: Panel study
    
    N: 56 patients (male CAD patients with
    12 clinical visits)
    
    Statistical Analysis: Linear and logistic
    regression models
    
    Dose-response Investigated? No
    Pollutant: PM25, PNC (n/crri)
    
    Averaging Time: Mean:
    Mass concentrations of PNC
    (0.1-2.84 n/cm3)
    
    Monitoring Stations:  1
    
    Copollutant: None
    PM Increment:. IQR
    
    Effect Estimate: Each IQR increase in
    0-23 h mean traffic particle concentration
    was associated with: QT interval: 0.6%
    (95% Cl:-0.3, 1.4)
    
    T wave amplitude: -1.6% (95% Cl: -3.3,
    0.1)
    
    vWF: 3.2% (95% Cl: -0.5,  7.0)
    
    CRP: (OR = 1.5
    
    95% Cl 1.0-2.3)
    
    Each IQR  increase in 0-23 h mean
    combustion-generated particle
    concentration was associated with: QT
    interval: 0.1%(-0.3, 0.6)
    
    T wave amplitude: -0.2% (-1.2, 0.7)
    
    vWF: 2.8% (0.8, 4.8)
    
    CRP (OR = 1.0
    
    0.8, 1.2)
    
    Notes: Five sources of particles were
    identified (airborne soil, local traffic-
    related ultrafine particles, combustion-
    generated  aerosols, diesel traffic-related
    particles, and secondary aerosols).
    Reference: Yue et al. (2007, 0979681
    
    Period of Study:
    Oct 12, 2000-Apr 27, 2001
    
    Location: Erfurt, Germany
    Outcome: QT interval, T wave
    amplitude, von Willebrand factor (vWF),
    C-reactive protein (CRP above 90th
    percentile compared to below)
    
    Age Groups: >50 yr
    
    Study Design: Panel (12 visits
    
    625 observations for repolarization
    parameters and 578 observations for
    inflammatory markers)
    
    N: 57 male coronary artery disease
    patients
    
    Statistical Analyses: Linear and logistic
    fixed-effects regression models
    (generalized additive models)
    
    Covariates: Trend, weekday, and
    meteorological variables  (temperature,
    relative humidity, barometric pressure)
    
    Dose-response Investigated? No
    
    Statistical Package: SASv9.1  and S-
    piusve.o
    Pollutant: Five particle source factors    PM Increment: IQR
    (airborne soil, local traffic-related
    ultrafine particles, combustion-generated
    aerosols, diesel traffic-related particles,
    and secondary aerosols); see below for
    size fractions (factor scores)
                                                                                Averaging Time: Used daily factor
                                                                                scores in analyses
    
                                                                                Mean (SD):
                                                                                Factor 1: particles from airborne soil
                                                                                (1.0-2.8  fjm): 2390 (1696)
    
                                                                                Factor 2: ultrafine particles from local
                                                                                traffic (0.01-0.1 pm):9931 (5858)
    
                                                                                Factor 3: secondary aerosols from local
                                                                                fuel combustion (0.1-0.5 pm): 3770
                                                                                (6129)
    
                                                                                Factor 4: particles from traffic (0.01-
                                                                                0.5 pm): 6865 (5689)
    
                                                                                Factor 5: secondary aerosols from
                                                                                multiple  sources (0.2-1.0 pm): 4732
                                                                                (3890)
                                                                                Median:
                                                                                Factor 1:2053
                                                                                Factor 2: 8531
                                                                                Factor 3:1348
                                                                                Factor 4: 5045
                                                                                Factor 5: 3752
                                                                                IQR (6-day avg):
                                                                                Factor 1:1110
                                                                                Factor 2: 5749
                                                                                Factor 3: 4124
                                                                                Factor 4: 5000
                                                                                Factor 5: 3393
                                                                                Range (Min, Max):
                                                                                Factor 1:284,12960
                                                                                Factor 2: 866, 26632
                                                                                Factor 3:139, 39097
                                                                                Factor 4: 283, 27605
                                                                                Factor 5: 67,  20129
                                                                                Monitoring Stations: 1 monitor
    Effect Estimate [Lower Cl, Upper Cl]:
    QT interval, % change (96%CI)
    Factor 1:
     0-5 h:-0.1 (-0.6,0.6)
    6-11 h: -0.5 (-1.1, 0.2)
    12-17 h: 0.1  (-0.4,0.4)
    18-23 h:-0.2 (-0.7, 0.2)
    0-23 h: -0.2 (-0.9, 0.4)
    1 day:-0.1 (-0.7,0.6)
    2 day: -0.3 (-0.9, 0.4)
    3 day:-0.7 (-1.4, 0.1
    4 day: -0.2 (-0.9, 0.5
    0-4 day avg:-0.7 (-1.8, 0.3)
    Factor 2:
    0-5 h: 0.2 (-0.4, 0.8)
    6-11h:0.8(-0.0, 1.7)
    12-17 h: 0.6 (-0.2, 1.4)
    18-23 h: 0.5 (-0.4, 1.4)
    0-23 h: 0.9 (-0.1, 2.0)
    1 day: 1.5 (0.3, 2.7)
    2 day:-0.4 (-1.7,1.0)
    3 day: 0.5 (-0.9,1.9)
    4 day: 0.1 (-1.2,1.4)
    0-4 day avg: 1.6 (-0.1, 3.3)
    Factors:
    0-5 h: 0.1 (-0.3,0.5)
    6-11 h: 0.2 (-0.3, 0.6)
    12-17 h: 0.2 (-0.3, 0.6)
    18-23 h: 0.1  (-0.3,0.4)
    0-23 h: 0.1 (-0.3, 0.6)
    1 day: 0.1 (-0.3, 0.4)
    2 day:-0.1 (-0.4,0.3
    3 day:-0.2 (-0.5, 0.2
    4 day:-0.1 (-0.5, 0.2)
    0-4 day avg:-0.1  (-0.7,0.6)
    Factor 4:
    0-5 h: 0.2 (-0.4, 0.8)
    6-11 h: 0.8 (0.0, 1.6)
    12-17 h: 0.5 (-0.2, 1.3)
    18-23 h: 0.5 (-0.2, 1.2)
    0-23 h: 0.6 (-0.3,  1.4)
    1 day:-0.4 (-1.5, 0.7)
    2 day:-0.9 (-2.0, 0.1)
    3 day:-0.5 (-1.4, 0.5)	
    December 2009
                                      E-73
    

    -------
                 Reference                       Design & Methods                   Concentrations1                Effect Estimates (95% Cl)
    
                                                                                    Copollutant:NA4 day: -0.5 (-130.2)
                                                                                       f                                    0-4 day avg: -0.3 (-1.7,1.1)
                                                                                                                            Factor 6:
                                                                                                                            nO-5h:1.0(-0.1,2.1)
                                                                                                                            6-11 h: 0.9 (-0.2, 2.0)
                                                                                                                            12-17 h: 0.3 (-0.7, 1.4)
                                                                                                                            18-23 h:-0.1 (-1.2, 1.0)
                                                                                                                            0-23h: 0.7 (-0.6, 1.9)
                                                                                                                            1 day: 0.1 (-1.1,1.3)
                                                                                                                            2 day:-0.2 (-1.5,1.1)
                                                                                                                            3 day:-0.6 (-1.9, 0.8
                                                                                                                            4 day:-0.9 (-2.0, 0.2
                                                                                                                            0-4 day avg:-0.4 (-1.9,1.2)
                                                                                                                            Twave amplitude, % change (96%CI)
                                                                                                                            Factor!:
                                                                                                                            0-5 h:-0.3 (-1.5, 0.9)
                                                                                                                            6-11 h:-0.6 (-1.9, 0.7)
                                                                                                                            12-17 h: 0.1 (-0.8,0.9)
                                                                                                                            18-23 h:-0.6 (-1.5, 0.4)
                                                                                                                            0-23 h:-0.5 (-1.8, 0.9)
                                                                                                                            1 day: 0.4 (-0.9,1.7)
                                                                                                                            2 day: 1.2
                                                                                                                            3 day: 0.2
               -0.3, 2.7)
               -1.2,  1.7)
    4 day:-0.2 (-1.3,1.0)
    0-4 day avg: 0.8 (-1.1, 2.6)
    Factor 2:
    0-5 h:-1.7 (-3.0 to-0.4)
    6-11 h:-2.6 (-4.5 to-0.6)
    12-17 h:-1.0 (-2.6, 0.7)
    18-23 h:-1.1  (-2.8,0.7)
    0-23 h:-3.1 (-5.3 to-0.9)
    1 day: -0.3 (-2.9, 2.2)
    2 day:-1.2 (-4.1,1.7)
    3 day:-0.5 (-3.2, 2.1
    4 day:-3.4 (-9.9, 3.1
    0-4 day avg:-1.5 (-4.4,1.5)
    Factor 31
    0-5 h:-0.3 (-1.1, 0.6)
    6-11 h:-0.1 (-0.9,0.9)
    12-17 h: 0.1 (-0.9, 1.0)
    18-23 h:-0.4 (-1.2, 0.4)
    0-23 h:-0.2 (-1.2, 0.7)
    1 day: 0.1 (-0.7,0.8)
    2 day:-0.1 (-0.7, 0.7)
    3 day: 0.4 (-0.3,1.1)
    4 day: 0.1 (-0.7,0.7)
    0-4 day avg: 0.3 (-0.9,1.5)
    Factor 4:
    0-5 h:-1.5 (-2.8 to-0.2)
    6-11 h:-1.3 (-3.0, 0.3)
    12-17 h:-1.1  (-2.7,0.4)
    18-23 h: -0.9 (-2.4, 0.6)
    0-23 h:-1.6 (-3.3, 0.1)
    1 day:-1.2 (-3.3, 0.9)
    2 day:-1.0 (-3.2,1.2)
    3 day: 0.2 (-1.5,1.9)
    4 day: 0.5 (-1.0,  2.0)
    0-4 day avg:-1.7 (-4.1,0.7)
    Factor 6:
    0-5 h:-1.6 (-3.6, 0.4)
    6-11 h:-0.1 (-2.1,2.0)
    12-17 h:-0.2 (-2.2, 1.8)
    18-23 h:-1.8 (-3.8, 0.2)
    0-23 h:-1.2 (-3.4, 1.0)
    1 day:-1.8 (-4.2, 0.6)
    2 day:-0.7 (-3.5, 2.1)
                                                                                                                            3 day: 0.8
                                                                                                                            4 day: 0.5
               -1.5, 3.2)
               -1.5, 2.5)
    0-4 day avg:-1.4 (-4.0,1.2)
    vWF, % change (95%CI)Factor 1:
    0-5 h: 1.1  (-1.5,3.6)
    6-11 h: 1.6 (-1.2, 4.5)
    12-17 h: 0.4 (-1.4, 2.1)
    18-23 h: 1.4 (-0.6, 3.5)
    0-23 h: 1.6 (-1.3, 4.4)
    1 day:-1.0 (-3.9,1.9)
    2 day:-1.8 (-4.8,1.2)	
    December 2009                                                         E-74
    

    -------
                 Reference                       Design & Methods                   Concentrations1               Effect Estimates (95% Cl)
    
                                                                                                                           3 day:-2.5 (-5.8, 0.9)
                                                                                                                           4 day: 0.5 (-2.9, 3.9)
                                                                                                                           0-4 day avg:-2.5 (-7.1,2.2)
                                                                                                                           Factor 2:
                                                                                                                           0-5 h: 0.4 (-2.4, 3.2)
                                                                                                                           6-11 h:-0.4 (-4.3, 3.4)
                                                                                                                           12-17 h: 2.1 (-1.4, 5.7)
                                                                                                                           18-23 h: 2.3 (-1.4, 5.9)
                                                                                                                           0-23 h: 1.9 (-2.8, 6.6)
                                                                                                                           1 day: 2.8 (-2.8, 8.3)
                                                                                                                           2 day: 5.1 (-0.8,11.1)
                                                                                                                           3 day: 11.4 (5.3,17.6)
                                                                                                                           4 day: 6.6 (0.0,13.1)
                                                                                                                           0-4 day avg: 11.4 (3.7,19.1)
                                                                                                                           Factor 31
                                                                                                                           0-5 h: 1.8 (0.1, 3.6)
                                                                                                                           6-11 h: 1.7 (-0.3, 3.7)
                                                                                                                           12-17 h: 2.2 (0.3, 4.2)
                                                                                                                           18-23 h: 2.8 (1.1, 4.5)
                                                                                                                           0-23 h: 2.8 (0.8, 4.8)
                                                                                                                           1 day: 2.7 (1.0, 4.4)
                                                                                                                           2 day: 3.4 (1.8, 5.0)
                                                                                                                           3 day: 2.3
                                                                                                                           4 day: 1.4
               0.8, 3.8)
               -0.2, 2.9)
    0-4 day avg: 4.8 (2.0, 7.6)
    Factor 4:
    0-5h:1.5(-1.4, 4.3)
    6-11h:2.0(-1.7, 5.6)
                                                                                                                           12-17h:2.6
                                                                                                                           18-23h: 3.5
                -0.8, 5.9)
                0.4, 6.6)
                                                                                                                           0-23h: 3.2 (-0.5, 7.0)
                                                                                                                           1 day: 5.4
                                                                                                                           2 day: 4.5
               0.6, 10.2)
               -0.6, 9.5)
    3 day: 3. 8 (-0.6, 8.1)
    4 day: 3.0 (-0.6, 6.6)
    0-4d avg: 11.3 (5.0, 17.6)
    Factors:
    0-5 h: 1.9 (-2.8, 6.6)
    6-11 h: 3.2  (-1.6, 8.0)
    12-17 h: 2.4 (-2.3, 7.1)
    18-23 h: 1.6  -3.1,6.2
    0-23 h: 2.9 (-2.5, 8.2)
    1 day: -2.2  (-7.6, 3.2)
    2 day: -1.3  (-7.4, 4.9)
    3 day: 1.1  (-4.8, 7.1)
    4 day: 1.3 (-4. 2, 6.7)
    0-4 day avg: 3.3 (-4.1, 10.6)
    
    CRP, Odds Ratio (96%CI)
    Factor 1
    0-5 h: 0.9 (0.7, 1.1)
    6-11 h: 1.4  (1.1, 1.8)
    12-17 h: 1.2 (1.0, 1.4
    18-23 h: 1.0 (0.8, 1.3
    0-23 h: 1.1  (0.9,  1.5)
    1 day: 1.4
    2 day: 1.3
                                                                                                                                      1.1, 1.8)
                                                                                                                                      1.0, 1.7)
                                                                                                                           3 day: 1.0 (0.7, 1.4)
                                                                                                                           4 day: 1.1 (0.9, 1.5)
                                                                                                                           0-4 day avg: 1.6 (1.1, 2.2)
                                                                                                                           Factor 2
                                                                                                                           0-5h: 0.8 (0.6, 1.0)
                                                                                                                           6-11h:1.0(0.7, 1.4)
                                                                                                                           12-17h:1.1(0.8,  1.5)
                                                                                                                           18-23h:1.0 0.8,  1.4)
                                                                                                                           0-23h: 0.9 (0.6, 1.4)
                                                                                                                           1 day: 0.9 (0.6, 1.5)
                                                                                                                           2 day: 2.1
                                                                                                                           3 day: 1.9
               1.3,3.3)
               1.0,3.6)
                                                                                                                           4 day: 1.4 (0.8, 2.3)
                                                                                                                           0-4d avg: 1.4 (0.8, 2.6)
                                                                                                                           Factor 3
                                                                                                                           0-5 h:  1.0 (0.8, 1.1)
                                                                                                                           6-11 h: 0.9 (0.8, 1.1)
                                                                                                                           12-17  h: 1.0 (0.9, 1.2)
                                                                                                                           18-23  h: 1.0 (0.8, 1.2)
                                                                                                                           0-23 h: 1.0 (0.8, 1.2)
                                                                                                                           1 day: 1.1 (1.0,1.3)
    December 2009                                                         E-75
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                  2 day: 1.0(0.9,1.2)
                                                                                                                  3 day: 1.2
                                                                                        1.1, 1.4)
                                                                                        1.0, 1.3)
                                                                                                                  4 day: 1.1
                                                                                                                  0-4dYavg:1.2(1.0,1.5)
                                                                                                                  Factor 4
                                                                                                                  0-5 h: 0.8 (0.6, 1.1)
                                                                                                                  6-11 h: 0.8 (0.6, 1.1)
                                                                                                                  12-17 h:  1.3 (1.0, 1.8
                                                                                                                  18-23 h:  1.1 (0.8, 1.5
                                                                                                                  0-23 h: 1.0 (0.7, 1.4)
                                                                                                                   1 day: 1.5
                                                                                                                   2 day: 2.0
                                                                                        1.0,2.3)
                                                                                        1.3,3.2)
                                                                              3 day: 1.5 (0.9, 2.3)
                                                                              4 day: 1.3 (0.9,1.8)
                                                                              0-4 day avg: 1.7 (1.0, 2.9)
                                                                              Factor 6
                                                                              0-5 h: 0.7 (0.5, 1.1)
                                                                              6-11 h: 1.4 (0.9, 2.1)
                                                                              12-17 h: 1.9 (1.3, 2.8)
                                                                              18-23 h: 1.4 (1.0, 2.0)
                                                                              0-23 h: 1.4 (0.9, 2.2)
                                                                              1 day: 1.6 (1.0, 2.6)
                                                                                                                  2 day: 1.6
                                                                                                                  3 day: 2.3
                                                                                       0.9, 2.6)
                                                                                       1.3,4.1)
                                                                                                                  4 day: 1.6 (0.9, 2.8)
                                                                                                                  0-4 day avg: 2.1 (1.2,3.8)
    Reference: Zanobetti et al. (2004,
    0874891
    Period of Study: 1999-2001
    
    Location: Boston, Massachusetts, USA
    Outcome: Blood pressure (systolic
    blood pressure, diastolic blood pressure,
    mean arterial blood pressure)
    
    Age Groups: Elderly
    
    Study Design: Panel study
    
    N: 62 elderly subjects with n = 631
    repeated visits for cardiac rehabilitation
    
    Statistical Analysis: Linear mixed
    effects models
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Median (10th-90th percentile)
    
    Median: 8.8 pg/m3
    
    10th-90th: 13.4
    
    Monitoring Stations: 1
    
    Copollutant: S02, 03, CO, N02, BC
    
    120-havg
    
    Median: 0.651
    
    10th-90th: 0.376
    PM Increment: .10.4 pg/m  for 5-day
    mean, 13.9pg/m  for2-daymean
    
    Effect Estimate: Each 10.4 pg/m3
    increase in 5-day mean PM25
    concentration was associated with:
    Systolic BP: 2.8mmHg (95% Cl: 0.1, 5.5)
    
    Diastolic BP: 2.7mmHg (95% Cl: 1.2,
    4.3)
    
    Mean arterial BP: 2.7mmHg (95% Cl:
    1.0,4.5)
    
    Each 13.9 pg/m3 increase in 2-day mean
    PM25, during exercise in person with
    HJObprn
    
    Diastolic:  7.0mmHg (95% Cl: 2.3,12.1)
    
    Mean arterial BP: 4.7mmHg (95% Cl:
    0.5,9.1)
    December 2009
                                     E-76
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Zeka et al. (2006,1571771
    
    Period of Study: Nov 2000-Dec 2004
    
    Location: Greater Boston area
    (Massachusetts)
    Outcome: White blood cells (WBC), C-
    reactive protein (CRP), sediment rate,
    fibrinogen
    
    Age Groups: Mean age (SD) = 73.0
    (6.7)
    
    Study Design: Cross-sectional
    
    N: 710 subjects
    
    Statistical Analyses: Linear regression
    
    Covariates: Age, BMI, season (also
    assessed potential for confounding by
    temperature, RH, barometric pressure,
    hypertensive or cardiac medications,
    hypertension, smoking, alcohol, and
    fasting glucose levels)
    
    Dose-response Investigated? No
    Pollutant: BC
    
    Averaging Time: Hourly (PN, BC,
    PM25) and 24-h (S042~) measurements
    used to create 48-h, 1-wk, and 4-wk ma
    
    Mean (SD): 0.77 (0.63)
    
    Percentiles: 50th: 0.61
    
    75th: 1.00
    
    90th: 1.51
    
    Monitoring Stations: 2 sites
    
    Units: ng/m3
    
    Copollutant (correlation):
    PM25(r = 0.52)
    
    BC
    
    PN(r = 0.30)
    
    S042"(r = 0.30)
    PM Increment: 1 SD increase
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % increase (95%CI) in biomarker per 1
    SD increase in pollutant.
    Fibrinogen
    48 h: 0.84 (-0.63, 2.31)
    1wk: 0.60 (-0.95, 2.15)
    4 wk: 1.78 (0.19, 3.36)
    CRP
    48 h: 4.51  (-2.03, 11.06)
                                                                                                                  1wk:1.07
                                                                                                                  4wk:5.41
              -5.55, 7.68)
              -1.00, 11.81)
                                                                                                                  Sediment rate
                                                                                                                  48 h:-4.56 (-25.55, 16.43)
                                                                                                                  1 wk: 1.98 (-18.15, 22.11)
                                                                                                                  4 wk: 21.65 (1.48, 41.82)
                                                                                                                  WBC count
                                                                                                                  48 h:-0.63 (-2.45, 1.19)
                                                                                                                  1 wk:-0.13 (-1.87,1.60)
                                                                                                                  4 wk:-0.55 (-2.36, 1.26)
                                                                                                                  Note: No statistically significant
                                                                                                                  difference was reported for any category
                                                                                                                  of effect modifiers (age, obesity,
                                                                                                                  medications, homozygousforthe
                                                                                                                  deletion of GSTM1-null, hypertension)
    
                                                                                                                  However, results suggested almost all
                                                                                                                  the effect of BC on sediment rate was
                                                                                                                  among  the younger group (<78 yr)
    
                                                                                                                  There was a 4-fold difference for the
                                                                                                                  association  between  BC and CRP in the
                                                                                                                  presence of obesity
    
                                                                                                                  Also evidence for effect modification by
                                                                                                                  obesity of the association between BC
                                                                                                                  and sediment rate
    
                                                                                                                  There was a suggestive greater effect of
                                                                                                                  BC on CRP among GSTM1-null subjects
                                                                                                                  (9.73% [1.48,  17.98]) vs..  GSTM1-
                                                                                                                  present subjects (-2.97%  [-14.05, 8.10]
                                                                                                                  for concentrations 4-wk prior)
    
                                                                                                                  A stronger effect of BC on sediment rate
                                                                                                                  was seen among non-users of statins
                                                                                                                   36.01% [13.88, 58.13]) vs.. users
                                                                                                                   •12.29% [39.13, 14.55])
    Reference: Zeka et al. (2006,1571771
    
    Period of Study: Nov 2000-Dec 2004
    
    Location: Greater Boston area
    (Massachusetts)
    Outcome: White blood cells (WBC), C-
    reactive protein (CRP), sediment rate,
    fibrinogen
    
    Age Groups: Mean age (SD) = 73.0
    (6.7)
    
    Study Design: Cross-sectional
    
    N: 710 subjects
    
    Statistical Analyses: Linear regression
    
    Covariates: Age, BMI, season (also
    assessed potential for confounding by
    temperature, RH, barometric pressure,
    hypertensive or cardiac medications,
    hypertension, smoking, alcohol, and
    fasting glucose levels)
    
    Dose-response Investigated? No
    Pollutant: S04
    
    Averaging Time: Hourly (PN, BC,
    PM25) and 24-h (S042~) measurements
    used to create 48-h, 1-wk, and 4-wk ma
    
    Mean (SD): 2.29 (1.62)
    
    Percentiles:
    50th: 1.84
    
    75th: 2.81
    
    90th: 4.10
    
    Monitoring Stations: 2 sites
    
    Copollutant (correlation):
     PM25(r = 0.50)
    
    BC(r = 0.30)
    
    PN(r = -0.15)
    
    S042"
    PM Increment: 1 SD increase
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % increase (95%CI) in biomarker per 1
    SD increase in pollutant.
    Fibrinogen:
    48 h: 0.60 (-1.23, 2.42)
    1wk:0.03 -1.93,1.99
    4wk:1.12 -0.52,2.77
    CRP:
    48 h: 1.57 (-7.13, 10.27)
    1 wk: 0.21 (-8.27, 8.69)
    4 wk: 5.29 (-1.91, 12.49)
    Sediment rate:
    48 h: 4.05 (-23.26, 31.36)
    1 wk: -5.87 (-32.39, 20.64)
    4 wk:-1.60 (-25.24, 22.04)
    WBC count:
    48 h:-0.12 (-2.35, 2.11)
    1 wk:-0.48 (-2.87, 1.90)
    4 wk: 0.75 (-1.30, 2.80)
    Note: No statistically significant
    difference was reported for any category
    of effect modifiers (age, obesity,
    medications, homozygousforthe
    deletion of GSTM1-null, hypertension)
    December 2009
                                     E-77
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Zeka et al. (2006,1571771
    
    Period of Study: Nov 2000-Dec 2004
    
    Location: Greater Boston area
    (Massachusetts)
    Outcome (ICD9 and ICD10): White
    blood cells (WBC), C-reactive protein
    (CRP), sediment rate, fibrinogen
    
    Age Groups: Mean age (SD) = 73.0
    (6.7)
    
    Study Design: Cross-sectional
    
    N: 710 subjects
    
    Statistical Analyses: Linear regression
    
    Covariates: Age, BMI, season (also
    assessed potential for confounding by
    temperature, RH, barometric pressure,
    hypertensive or cardiac medications,
    hypertension, smoking, alcohol, and
    fasting glucose levels)
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Pollutant: PM25
    
    Averaging Time: Hourly (PN, BC,
    PM25) and 24-h (S042~) measurements
    used to create 48-h,  1-wk, and 4-wk ma
    
    Mean (SD): 11.16 (7.95)
    
    Percentiles:
    50th: 9.39
    
    75th: 14.57
    
    90th: 21.48
    
    Monitoring Stations: 2 sites
    
    Copollutant (correlation):
    PM25
    
    BC(r = 0.52)
    
    PN(r = -0.02)
    
    S042"(r = 0.50)
    PM Increment: 1 SD increase
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % increase (95%CI)  in biomarker per 1
    SD increase in pollutant.
    Fibrinogen: 48 h:-0.18 (-1.93,1.57)
    1wk:-1.39 (-3.46, 0.67)
    4wk: 1.14 (-0.60, 2.88)
    CRP: 48 h: -4.88 (-13.29, 3.53)
    1 wk: -1.37 (-10.44, 7.71)
    4 wk: 4.36 (-3.25, 11.96)
    Sediment rate: 48 h: -16.91  (-43.66,
    9.84)
    1 wk: -18.89 (-47.48, 9.70)
    4 wk: 24.93 (0.68, 49.18)
    WBC count: 48 h: -3.18 (-5.39 to -0.97)
    1 wk: -0.51 (-3.02, 2.00)
    4 wk:-0.03 (-2.17, 2.10)
    Note: No statistically significant
    difference was reported for any category
    of effect modifiers (age, obesity,
    medications, homozygousforthe
    deletion of GSTM1-null,  hypertension)
    Reference: Zhang et al. (2009,1919701
    
    Period of Study: 1999-2003
    
    Location: U.S.
    Outcome: Myocardial Ischemia
    
    Age Groups: 52-90
    
    Study Design: Panel
    
    N: 55,529
    
    Statistical Analyses: Logistic & Linear
    Regression
    
    Covariates: Age, race/ethnicity,
    education, exam site, BMI, current
    smoking status, history of CHD,
    diabetes, hypertension, SBP, chronic
    lung disease,  or hypercholesterolemia,
    day of week, time of day, temperature,
    dew point, pressure, season
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags  Considered: 0-5-day
    Pollutant: PM25
    
    Averaging Time: NR
    
    Mean (SD):
    
    Lag 0:14.1 (8)
    
    Lag 1:13.8 (8)
    
    Lag 2:13.8 (8)
    
    Lag 3:13.8 (8)
    
    Lag 4:13.9 (8)
    
    Lag 5:14.1 (8)
    
    Lag 0-2:13.9 (7)
    
    Monitoring Stations: NRJ
    
    Co-pollutant: NR
    
    I Monitors used in model for spatial
    interpolation of daily PM values.
    PM Increment: 10 pg/m
    
    Odds Ratio (Lower Cl, Upper Cl), l
    
    Minnesota Codes*
    MC4:1.04
    MC4:1.04
              0.97,  1.10), lag 0-2
                                                                                                                                      0),
                                                                                                                               0.98, 1.11), lag 3-5
                                                                                                                    MC5: 1.05 (1.00, 1.09), lag 0-2
                                                                                                                    MC5: 1.04 (1.00, 1.08), lag 3-5
                                                                                                                    MC 4 or 5: 1.04 (1.00, 1.09), lag 0-2
                                                                                                                    MC 4 or 5: 1.03 (0.99, 1.07), lag 3-5
                                                                                                                    Change (Lower Cl, Upper Cl), lag:
    
                                                                                                                    ST-segment amplitude
                                                                                                                    Lead I: -0.07 (-0.36, 0.21), lag 0-2
                                                                                                                    Lead I: 0.1 8 (-0.10, 0.46), lag 3-5
                                                                                                                    Lead II: -0.12 (-0.47, 0.23), lag 0-2
                                                                                                                    Lead II: 0.16 (-0.18, 0.50), lag 3-5
                                                                                                                    Lead aVL: -0.01 (-0.25, 0.23), lag 0-2
                                                                                                                    Lead aVL: 0.11 (-0.12, 0.34), lag 3-5
                                                                                                                    Lead V1: -0.02 (-0.39, 0.35), lag 0-2
                                                                                                                    Lead V1: -0.22 (-0.58, 0.14), lag 3-5
                                                                                                                    Lead V2: 0.07 (-0.57, 0.70), lag 0-2
                                                                                                                    Lead V2: -0.01  (-0.61, 0.62), lag 3-5
                                                                                                                    Lead V3: -0.11  (-0.68, 0.47),  lag 0-2
                                                                                                                    Lead V3: -0.02 (-0.58, 0.54), lag 3-5
                                                                                                                    Lead V4: -0.0.3 (-0.51, 0.45), lag 0-2
                                                                                                                    Lead V4: 0.24 (-0.23, 0.71), lag 3-5
                                                                                                                    Lead V5: -0.01  (-0.41, 0.39), lag 0-2
                                                                                                                    Lead V5: 0.35 (-0.04, 0.74), lag 3-5
                                                                                                                    Lead V6: 0.02 (-0.30, 0.33), lag 0-2
                                                                                                                    Lead V6: 0.35 (0.04, 0.65), lag 3-5
                                                                                                                    T-wave amplitude
                                                                                                                    Lead I:-1.60
                                                                                                                    Lead I: -0.31
                                                                                           -3.07,-0.13), lag 0-2
                                                                                                                                -1.73,1.11), lag 3-5
                                                                                                                    Lead 11:-0.54 (-1.99, 0.92), lag 0-2
                                                                                                                    Lead II: 0.71 (-0.70, 2.13), lag 3-5
                                                                                                                    Lead aVL:-1.21 (-2.50, 0.10), lag 0-2
                                                                                                                    Lead aVL:-0.55 (-1.18, 0.71), lag 3-5
                                                                                                                    Lead V1:1.45 (-0.16, 3.06, lag 0-2
                                                                                                                    Lead V1: 0.03 (-1.53,1.59, lag 3-5
                                                                                                                    Lead V2:-0.18 (-2.96, 2.60), lag 0-2
                                                                                                                    Lead V2: 0.57 (-2.12, 3.27), lag 3-5
                                                                                                                    Lead V3:-2.33 (-5.15, 0.49), lag 0-2
                                                                                                                    Lead V3:-0.13 (-2.87, 2.60), lag 3-5
                                                                                                                    Lead V4:-2.03 (-4.69, 0.63), lag 0-2
                                                                                                                    Lead V4: 0.64 (-1.94, 3.22), lag 3-5
                                                                                                                    Lead V5:-1.92 (-4.22, 0.38), lag 0-2
                                                                                                                    Lead V5: 0.55 (-1.69, 2.78), lag 3-5
                                                                                                                    Lead V6:-0.63 (-2.36,1.10), lag 0-2
                                                                                                                    Lead V6: 0.82 (-0.86, 2.49), lag 3-5
                                                                                                                    QRS/T angles and heart rate (change)
    December 2009
                                     E-78
    

    -------
                Reference
            Design & Methods
              Concentrations1
          Effect Estimates (95% Cl)
                                                                                                                 QRS/T angle-spatial (°):0.19 (-0.21,
                                                                                                                 0.59), lag 0-2
    
                                                                                                                 QRS/T angle-spatial (°): -0.20 (-0.59,
                                                                                                                 0.19), lag 3-5
    
                                                                                                                 QRS/T angle-frontal (°): 0.13 (-0.24,
                                                                                                                 0.50), lag 0-2
    
                                                                                                                 QRS/T angle-frontal (°): 0.35 (-0.01,
                                                                                                                 0.71), lag 3-5
    
                                                                                                                 Heart Rate (beats/min): 0.16 (0.02,
                                                                                                                 0.30), lag 0-2
    
                                                                                                                 Heart Rate (beats/min): 0.04 (-0.10,
                                                                                                                 0.18), lag 3-5
    
                                                                                                                 *Any ST abnormality (MC 4.1 -4.4)
    
                                                                                                                 Any T abnormality (MC 5.1-5.4)
    1AII units expressed in ug/m3 unless otherwise specified.
    Table E-4.      Short-term exposure-cardiovascular morbidity studies:  Other size fractions.
                Reference
           Design & Methods
            Concentrations
        Effect Estimates (95% Cl)
    Reference: Adar et al. (2007, 0014581
    
    Period of Study: Mar-Jun 2002
    
    Location: St. Louis, Missouri
    Outcome: Heart rate variability: heart
    rate, standard deviation of all normal-to-
    normal intervals (SDNN), square root of
    the mean squared difference between
    adjacent normal-to-normal intervals
    (rMSSD), percentage of adjacent
    normal-to-normal intervals that differed
    by more than 50 ms (pNNSO), high
    frequency power (HF in the range of
    0.15-0.4Hz), low frequency power (LF,
    in the  range of 0.04-0.15Hz), and the
    ratio of LF/HF
    
    Age Groups: > 60 yr
    
    Study Design: Panel (4 planned
    repeated measures with a total of 158
    person-trips 35 participating in all 4
    trips)
    
    N: 44  participants
    
    Statistical Analyses: Generalized
    additive models
    
    Covariates: Subject, weekday, time,
    apparent temperature, trip type, activity,
    medications, and autoregressive terms
    
    Season: Limited data collection period
    
    Dose-response Investigated? No
    
    Statistical Package: SAS v8.02, R
    V2.0.1
    Pollutant: Particle count fine (PC fine)
    (particles/cm3)
    
    Averaging Time: Measurements
    collected over 48-h period surrounding
    the bus trip (during which health
    endpoints were measured) used to
    calculate 5-, 30-, 60-min, 4-h, 24-h ma
    
    Median (IQR):
    All: 42 (57)
    Facility: 36 (45)
    Bus: 105 (96)
    Activity: 50 (133)
    Lunch: f" ""
                                                                           Monitoring Stations: 2 portable carts
    
                                                                           Copollutant:
                                                                           PM25
                                                                           BC
                                                                           Fine particle counts
                                                                           Coarse particle counts
    
                                                                           Correlation notes: 24-h mean PM25,
                                                                           BC, and fine particle count
                                                                           concentrations ranged from 0.80 to 0.98
    
                                                                           r = 0.76 to 0.97 when limited to time
                                                                           spent on the bus
    
                                                                           r = 0.55 to 0.86 when comparing bus
                                                                           concentrations to 24-h ma
    
                                                                           r = -0.003 to 0.51 when comparing 5-
                                                                           min avg and 24-h ma. Poor correlations
                                                                           found between coarse particle count
                                                                           concentrations and all fine particulate
                                                                           measures during all times periods
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change (95%CI) in HRV per IQR in
    the 24-h ma of the microenvironmental
    pollutant (IQr = 39 pt/cm3)
    
    Single-pollutant models
    
    SDNN:-5.1  (-5.8 to-4.4)
    
    rMSSD:-8.0 (-8.7 to-7.2)
    
    pNN50+1:-10.2 (-11.3to-9.0)
    
    LF:-9.9 (-11.4 to-8.4)
    
    HF:-13.7 (-15.1 to-12.2)
    
    LF/HF: 4.3 (3.1, 5.5)
    
    H: 0.9 (0.8, 1.1)
    
    Note: Exposure to health associations
    by all lag periods  presented in Fig 2
    (magnitude of associations increased
    with averaging period, with the largest
    associations consistently found for 24-h
    December 2009
                                     E-79
    

    -------
                Reference
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Adar et al. (Adar et al.,
    2007, 0014581
    
    Period of Study: Mar-Jun 2002
    
    Location: St.  Louis, Missouri
    Outcome: Heart rate variability: heart
    rate, standard deviation of all normal-to-
    normal intervals (SDNN), square root of
    the mean squared difference between
    adjacent normal-to-normal intervals
    (rMSSD), percentage of adjacent
    normal-to-normal intervals that differed
    by more than 50 ms (pNNSO), high
    frequency power (HF in the range of
    0.15-0.4Hz), low frequency  power (LF,
    in the range of 0.04-0.15Hz), and the
    ratio of LF/HF
    
    Age Groups:  > 60 yr
    
    Study Design: Panel (4 planned
    repeated measures with a total of 158
    person-trips
    
    35 participating in all 4 trips)
    
    N: 44 participants
    
    Statistical Analyses: Generalized
    additive models
    
    Covariates: Subject, weekday, time,
    apparent temperature, trip type, activity,
    medications, and autoregressive terms
    
    Season: Limited data collection period
    
    Dose-response Investigated? No
    
    Statistical Package: SAS v8.02, R
    V2.0.1
    Pollutant: Particle count coarse (PT     PM Increment: IQR
    coarse) (pt/cm ]
    
    Averaging Time: Measurements
    collected over 48-h period surrounding
    the bus trip (during which health
    endpoints were measured) used to
    calculate 5-, 30-, 60-min, 4-h, and 24-h
    ma
    
    Median (IQR):
    All: 0.02 (0.11)
    Facility: 0.01 (0.04)
    Bus: 0.16 (0.13)
    Activity: 0.29 (0.26)
    Lunch: 0.16 (0.36)
    
    Monitoring Stations: 2 portable carts
    Copollutant:
    PM25
    BC
    Fine particle counts
    Coarse particle counts
    Correlation notes: 24-h mean PM25,
    BC, and fine particle count
    concentrations ranged from 0.80 to 0.98
    
    r = 0.76 to 0.97 when  limited to time
    spent on the bus
    
    r = 0.55 to 0.86 when  comparing bus
    concentrations to 24-h ma
    
    r = -0.003 to 0.51  when comparing 5-
    min avg and 24-h ma. Poor correlations
    found between coarse particle count
    concentrations and all fine particulate
    measures during all times periods
    Effect Estimate [Lower Cl, Upper Cl]:
    % change (95%CI) in HRV per IQR in
    the 24-h ma of the microenvironmental
    pollutant (IQr = 0.066 pt/cm3)
    
    Single-pollutant models
    
    SDNN: 2.4 (1.3, 3.6)
    
    rMSSD: 3.9 (2.6,  5.1)
    
    pNN50+1:2.9 (1.0, 4.9)
    
    LF: 6.4 (3.7, 9.1)
    
    HF: 10.2 (7.4, 13.1)
    
    LF/HF:-3.3 (-5.0 to-1.6)
    
    H:-1.1  (-1.3(0-0.8)
    
    Two-pollutant models (with PM25):
    SDNN:-0.7 (-1.9, 0.6)
    
    rMSSD:-1.3 (-2.6 to-0.05)
    
    pNN50+1:-4.3(-6.3to-2.4)
    
    LF: 0.2 (-2.5, 3.0)
    
    HF: 1.3 (-1.5, 4.1)
    
    LF/HF:-0.9 (-2.7, 1.0)
    
    H:-0.6 (-0.9 to-0.4)
    
    Note: Exposure to health associations
    by all lag  periods presented in Fig 2
    (magnitude of associations increased
    with averaging period, with the largest
    associations consistently found for 24-h
    ma)
    Reference: Delfmo et al. (2008,
    1563901
    
    Period of Study: 2005-2006
    
    Location: Los Angeles, California, air
    basin
    Outcome: C-reactive protein (CRP)
    
    Fibrinogen, tumor necrosis factor-a
     TNF-a) and its soluble receptor-ll
     TNF-RII)
    
    lnterleukin-6 (IL-6) and its soluble
    receptor (IL-6sR)
    
    Fibrin D-dimer
    
    Soluble platelet selectin (sP-selectin)
    
    Soluble vascular cell adhesion mole-
    cule-1 (sVCAM-1)
    
    Intracellular adhesion molecule-1
    (slCAM-1) and myeloperoxidase (MPO)
    
    Erythrocyte lysates for glutathione
    peroxidase-1 (GPx-1)
    
    Copper-zinc superoxide dismutase (cu,
    Zn-SOD)
    
    Age Groups:  2 65 yr
    
    Study Design: Panel (biomarkers
    measured weekly 12 times)
    
    N: 29 participants (nonsmoking with
    history of coronary artery disease)
    
    Statistical Analyses: Mixed models
    
    Covariates: temperature (infectious
    illnesses were excluded by excluding
    weeks with such observations)
    
    Season: Collected 6 wk of data during
    warm period and 6 wk of data during
    Pollutant: PM (multiple size fractions
    and components)
    
    Averaging Time: 24-h avg preceding
    the blood draw (lag 0) and cumulative
    avg up to 5 days preceding the draw
    
    Outdoor hourly PM: EC: Mean (SD):
    1.61  (0.62)
    Median: 1.56
    IQR: 0.92
    Min,  Max: 0.24, 3.94
    OC:  Mean (SD): 5.94 (2.11)
    Median: 5.58
    IQR: 2.79
    Min-Max: 2.51,13.60
    BC: Mean (SD): 2.00 (0.77)
    Median: 1.89
    IQR: 0.96
    Min-Max: 0.58, 5.11
    OCpri: Mean (SD): 3.37 (1.21)
    Median: 3.21
    IQR: 1.63
    Min-Max: 0.99, 7.11
    Secondary OC: Mean (SD): 2.49 (1.50)
    Median: 2.10
    IQR: 1.86
    Min-Max: 0,8.10
    PN (p/cm3): Mean (SD): 16,043 (5886)
    Median: 13,968
    IQR: 7,386
    Min-Max: 6837, 31263
    Indoor hourly PM EC: Mean (SD):
    1.31  (0.52)
    Median: 1.30
    IQR: 0.70
    Min-Max: 0.19, 2.89
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Note: Nearly all results presented in
    figures
    
    Results: The authors found significant
    positive associations for CRP, IL-6,
    sTNF-RII, and sP-selectin with outdoor
    and/or indoor concentrations of quasi-
    ultrafme PM Ł 0.25 pm in diameter, EC,
    OCpri, BC, PN, CO, and nitrogen
    dioxide from the current-day and
    multiday avg. There were consistent
    positive but largely nonsignificant
    coefficients for TNF-a, sVCAM-1, and
    slCAM-1, but not fibrinogen, IL-6sR, or
    D-dimer. The authors found inverse
    associations for erythrocyte Cu, Zn-
    SOD with these pollutants and other PM
    size fractions (0.25-2.5 and 2.5-10 pm).
    Inverse associations of GPx-1 and MPO
    with pollutants were largely
    nonsignificant. Indoor associations were
    often stronger for estimated indoor EC,
    OCpri, and PN of outdoor origin than for
    uncharacterized indoor measurements.
    There was no evidence for positive
    associations with SOA.
    December 2009
                                      E-80
    

    -------
               Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                       cool period
    
                                       Dose-response Investigated? No
    
                                       Statistical Package: NR
                                       EC of outdoor origin: Mean (SD): 1.11
                                       (0.39)
                                       Median: 1.06
                                       IQR: 0.51
                                       Min-Max: 0.41, 2.97
                                       OC:Mean(SD):5.69(1.51)
                                       Median: 5.60
                                       IQR: 1.96
                                       Min-Max: 2.34,10.79
                                       OCpri of outdoor origin: Mean (SD):
                                       2.18(0.82)
                                       Median: 2.15
                                       IQR: 1.07
                                       Min-Max: 0.32, 5.21
                                       Secondary OC of outdoor origin: Mean
                                       (SD): 2.08 (1.26)
                                       Median: 1.75
                                       IQR: 1.45
                                       Min-Max: 0, 6.87
                                       PN (particles/cm3): Mean (SD):  14,494
                                       (6770)
                                       Median: 12,341
                                       IQR: 7,337
                                       Min-Max: 1016, 43027
                                       PN of outdoor origin (p/cm3):  Mean
                                       (SD):10,108(3108)
                                       Median: 9,580
                                       IQR: 3,684
                                       Min-Max: 1016,17700
                                       Outdoor PM mass PM0.25: Mean
                                       (SD): 9.47 (2.97)
                                       Median: 9.4
                                       IQR: 4.2
                                       Min-Max: 3.31,18.75
                                       PMO.25-2.5: Mean (SD): 13.53 (10.67)
                                       Median: 11.7
                                       IQR: 11.5
                                       Min-Max: 1.29, 66.77
                                       PM10.2.5: Mean  (SD):  10.04 (4.07)
                                       Median: 9.9
                                       IQR: 5.9
                                       Min-Max: 1.76, 22.38
                                       Indoor PM mass PM0.25: Mean (SD):
                                       10.45(6.77)
                                       Median: 9.5
                                       IQR: 4.5
                                       Min-Max: 1.42, 69.86
                                       PMO.25-2.5 (pg/m3):  Mean (SD): 7.36
                                       (4.57)
                                       Median: 6.5
                                       IQR: 5.7
                                       Min-Max: 0.77, 30.86
                                       PMio-25: Mean  (SD): 4.12 (4.76)
                                       Median: 2.8
                                       IQR: 3.5
                                       Min-Max: 0.12, 37.63
                                       Copollutant: Outdoor hourly gases
                                       (N02, CO, 03) and indoor hourly gases
                                       (N02, CO)
    Reference: Pekkanen et al. (2002,
    0350501
    
    Period of Study: Winter 1998-1999
    
    Location: Helsinki, Finland
    Outcome: ST Segment Depression
    (>0.1mV)
    
    Study Design: Panel of ULTRA Study
    participants
    
    N: 45 Subjects, n = 342 biweekly
    submaximal exercise tests, 72 exercise
    induced ST Segment Depressions
    
    Statistical Analysis: Logistic
    regression / GAM
    Pollutant: UltrafmeNCO.01-0.1 pm
    (n/cm3)
    
    Averaging Time: 24 h
    
    Median: 14,890
    
    IQR: 9830
    
    Monitoring Stations: 1
    
    Copollutant: N02, CO, PM25, PMi0.25,
    PMi.ACP
    PM Increment: IQR
    
    Effect Estimate(s): NCO.01-0.1: OR
    = 3.14(1.56, 6.32), lag 2
    
    Notes: The effect was strongest for
    ACP and PM25, which in 2 pollutant
    models appeared independent.
    Increases in N02 and CO were also
    associated with increased risk of ST
    segment depression,  but not with
    coarse particles.
    December 2009
                                    E-81
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Peters et al. (2005,
    0957471
    Also Peters et al, 2005 (2005,1568591
    Period of Study: Feb 1999-Jul 2001
    Location: Augsburg, Germany
    Outcome: Myocardial infarction
    Study Design: Case-crossover
    N: 691 myocardial infarction patients
    Statistical Analysis: Conditional
    logistic regression
    Dose-response investigated
    (yes/no)? No
    Pollutant: Ultrafine (TNC) (n/cm ,
    Averaging Time:
    1 h: Median = 10,001
    IQR: 7919
    24 h: Median = 10,934
    IQR: 6276
    Copollutant: N02, S02, CO
    PM Increment: Effect Estimate: 2-h
    lag: OR = 0.95
    95% Cl: 0.84, 1.06
    24-h mean, 2-day lag: OR = 1.04
    95% Cl: 0.90, 1.20
    Notes: Examined triggering for Ml at
    various lags before Ml onset (up to 6 h
    before Ml,  up to 5 days  before Ml).  No
    statistically significant increases in
    lagged ultrafine particle concentration
    were found.
    Reference: Ruckerl et al. (2006,
    0887541
    Period of Study: Oct 2000-Apr 2001
    Location: Erfurt, Germany
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome (ICD9 and ICD10):
    C-reactive protein (CRP)
    Serum amyloid A (SAA)
    E-selectin
    von Willebrand Factor (vWF)
    Intercellular adhesion molecule-1
    (ICAM-1)
    Fibrinogen
    Factor VII
    Prothrombin fragment 1+2
    D-dimer
    
    Age Groups: 50+ yr
    
    Study Design: Panel (12 repeated
    measures at 2-wk intervals)
    N: 57 male subjects with coronary
    disease
    Statistical Analyses: Fixed effects
    linear and logistic regression models
    Covariates: Models adjusted for
    different factors based on health
    end point
    
    CRP: RH, temperature, trend, ID
    
    ICAM-1: temperature, trend, ID
    vWF: air pressure, RH, temperature,
    trend, ID
    
    FVII: air pressure, RH, temperature,
    trend, ID, weekday
    Season: Time trend as covariate
    Dose-response Investigated?
    Sensitivity analyses examined nonlinear
    exposure-response functions
    Statistical Package: SAS v8.2 and S-
    Dh ir« wC n
    Pollutant: AP (n/cm3)
    Averaging Time: 24 h
    Mean (SD): 1593 (1034)
    
    Percentiles:
    9"v R91
    ZJ. OZ I
    50: 1238
    75: 2120
    Range (Min, Max): 328, 4908
    Unit (i.e. pg/m3): n/cm3
    Monitoring Stations: 1 site
    
    Copollutant:
    UFPs
    AP
    PM25
    PM
    r Ivlio
    oc
    EC
    N02
    
    CO
    
    
    
    
    
    
    
    
    
    
    PM Increment: IQR (1299
    5-day avg: 11 27)
    Effect Estimate [Lower Cl, Upper Cl]:
    Effects of air pollution on blood markers
    presented as OR (95%CI) for an
    increase in the blood marker above the
    90th percentile per increase in IQR air
    pollutant.
    CRP
    Time before draw:
    0 to 23 h: 0.7 (0.5, 1.2)
    24 to 47 h: 1.5 0.9,2.6
    48 to 71 h: 3.2 1.7,6.0
    5-day mean: 1.5(0.8, 3.0)
    ICAM-1
    Time before draw:
    0 to 23 h: 0.6 (0.4, 0.9)
    24 to 47 h' 1 8 12 28
    48 to 71 h: 1.6 1.o|2.5
    5-day mean: 0.9 (0.6, 1.5)
    Effects of air pollution on blood markers
    presented as % change from the
    mean/GM in the blood marker per
    increase in IQR air pollutant.
    vWF
    Time before draw:
    0 to 23 h: 4.8 (0.2, 9.3)
    24 to 47 h: 5.9 (0.4, 11.5)
    48 to 71 h: 7.0 (0.7, 13.4)
    5-day mean: 13.5(6.3,20.6)
    FVII
    Time before draw:
    0 to 23 h: 0.0 (-2.9, 3.0)
    24 to 47 h: -2.9 (-6.1, 0.4)
    48 to 71 h: -3.6 (-6.8 to -0.3)
    5-day mean: -4.1 (-7.9 to -0.3)
    Note: Summary of results presented in
    figures.
    SAA results indicate increase in
    association with PM (not as strong and
    consistent as with CRP)
    No association observed between E-
    selectin and PM
                                                                                                                An increase in prothrombin fragment
                                                                                                                1+2 was consistently observed,
                                                                                                                particularly with lag 4
                                                                                                                Fibrinogen results revealed few
                                                                                                                significant associations, potentially due
                                                                                                                to chance
                                                                                                                D-dimer results revealed null
                                                                                                                associations in linear and logistic
                                                                                                                analyses
    December 2009
                                     E-82
    

    -------
    Reference
    Reference: Ruckerl et al. (2006,
    0887541
    Period of Study: Oct 2000-Apr 2001
    Location: Erfurt, Germany
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Soluble CD40 ligand
    (SCD40L), platelets, leukocytes,
    erythrocytes, hemoglobin
    Age Groups: 50+ yr
    
    Study Design: Panel (12 repeated
    measures at 2-wk intervals)
    N: 57 male subjects with coronary
    disease
    
    Statistical Analyses: Fixed effects
    linear regression models
    Covariates: Long-term time trend,
    weekday of the visit, temperature, RH,
    barometric pressure
    
    Season: Time trend as covariate
    Dose-response Investigated? No
    Statistical Package: SAS v8.2 and S-
    piusve.o
    
    
    
    
    
    
    
    
    
    
    Concentrations1
    Pollutant: AP (n/cm3)
    Averaging Time: 24 h
    Mean (SD): 1593 (1034)
    
    Percentiles:
    25th: 821
    50th: 1238
    75th: 2120
    Range (Min, Max): 328, 4908
    Monitoring Stations: 1 site
    Copollutant:
    UFPs
    
    AP
    PM25
    PM10
    
    NO
    
    
    
    
    
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: IQR (1299
    5-day avg: 11 27)
    Effect Estimate [Lower Cl, Upper Cl]:
    Effects of air pollution on blood markers
    presented as % change from the
    mean/GM in the blood marker per
    increase in IQR air pollutant.
    SCD40L, % change GM (pg/mL)
    lagO: 6.9 (0.5, 13.8)
    Iag1:-1.1(-8.0, 6.4)
    Iag2: -4.9 (-11.9, 2.7)
    Iag3: -3.8 (-10.3, 3.2)
    5-day mean: -1.3 (-9.9, 8.1)
    Platelets, % change mean (103/ul)
    Iag0:-1.0 -2.5,0.5
    Iag1:-0.4 -2.1, 1.6
    Iag2:0.8(-1.0,2.4)
    Iag3:0.0(-1.8, 1.7)
    5-day mean: -0.9 (-3.0, 1.3)
    Leukocytes, % change in mean
    (103/ul)
    Iag0:-1.9(-3.8to-0.1)
    lag1:-0.6(-2.9, 1.6)
    Iag2: -0.6 (-3.2, 2.0)
    Iag3: -2.3 (-4.6, 0.1)
    5-day mean: -2.7 (-5.5, 0.1)
    Erythrocytes, % change mean
    (106/ul)
    Iag0:-0.1(-0.5, 0.3)
    Iag1:-0.4 -0.9,0.2
    Iag2: -0.4 -0.9, 0.2
                                                                                                                Iag3: -0.4 (-0.6, 0.3)
                                                                                                                5-day mean:-0.4 (-1.0, 0.2)
                                                                                                                Hemoglobin, % change mean (g/dl)
                                                                                                                lagO: -0.2 (-0.7, 0.4)
                                                                                                                lag 1:-0.3
                                                                                                                Iag2:-0.1
                                                                                     -1.0,0.4
                                                                                     -0.9, 0.7
                                                                                                                Iag3:-0.1(-0.8, 0.6)
                                                                                                                5-day mean: -0.2 (-1.1, 0.6)
    Reference: Ruckerl et al. (2007,
    1569311
    
    Period of Study: May 2003-Jul 2004
    
    Location: Athens, Augsburg,
    Barcelona, Helsinki, Rome, and
    Stockholm
    Outcome: lnterleukin-6
    
    (IL-6), fibrinogen, C-reactive protein
    (CRP)
    
    Age Groups: 35-80 yr
    
    Study Design: Repeated measures /
    longitudinal
    
    N: 1003 Ml survivors
    
    Statistical Analyses: Mixed-effect
    models
    
    Covariates: City-specific confounders
    (age, sex,  BMI)
    
    Long-term time trend and apparent
    temperature
    
    RH, time of day, day of week included if
    adjustment improved model fit
    
    Season: Long-term time trend
    
    Dose-response Investigated? Used p-
    splines to allow for nonparametric
    exposure-response functions
    
    Statistical Package: SAS v9.1
    Pollutant: UFP (n/cm3)
    
    Averaging Time: Hourly and 24 h (lag
    0-4, mean of lags 0-4, mean of lags 0-1,
    mean of lags2-3, means of lags 0-3)
    
    Mean (SD): Presented by city only
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: Central
    monitoring sites in each city
    
    Copollutant:
    S02
    
    03
    
    NO
    
    NO,
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    % change in mean blood markers per
    increase in IQR of air pollutant.
    IL-6
    Lag (IQR): % change in GM (95%CI)
    Lag 0(11852): 1.88 (-0.16, 3.97)
    Lag 1(11852):-0.67 (-2.56, 1.25)
    Lag2(11852):-2.12 (-4.03 to-0.17)
    5-day avg (11003): -0.93 (-3.37,1.56)
    
    Fibrinogen
    Lag (IQR): % change in AM (95%CI)
    Lag 0(11852): 0.40 (-0.40, 1.19)
    Lag1 (11852): 0.11 (-0.69,0.91)
    Lag 2 (11852): 0.09 (-0.71, 0.90)
    5-day avg (11003): 0.50 (-2.20, 3.20)
    
    CRP
    Lag (IQR): % change in GM (95%CI)
    Lag 0(11852): 1.33 (-3.05, 5.90)
                                                                                                                Lag1
                                                                                                                Lag 2
                                              11852
                                              11852
                                                                                                                             -1.52
                       -4.39, 1.45
                       -6.70, 3.71
                                                                                                                5-day avg (11003): -0.08 (-3.78, 3.75)
    December 2009
                                     E-83
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Pekkanen et al. (2002,
    0350501
    
    Period of Study: Winter 1998-1999
    
    Location: Helsinki, Finland
    Outcome: ST Segment Depression
    (>0.1mV)
    
    Age Groups: Study Design: Panel of
    ULTRA Study participants
    
    N: 45 Subjects, n = 342 biweekly
    submaximal exercise tests, 72 exercise
    induced ST Segment Depressions
    
    Statistical Analysis: Logistic
    regression / GAM
    Pollutant: Ultrafme NCO.01-0.1 pm      PM Increment: IQR
    (n/cm ]
    
    Averaging Time: 24 h
    
    Median: 14,890
    
    IQR: 9830
    
    Monitoring Stations: 1
    
    Copollutant: N02, CO, PM25, PMio.25,
    PM,,ACP
    Effect Estimate(s): NCO.01-0.1: OR
    = 3.14(1.56, 6.32), lag 2
    
    Notes: The effect was strongest for
    ACP and PM25, which in 2 pollutant
    models appeared independent.
    Increases in N02 and CO were also
    associated with increased risk of ST
    segment depression, but not with
    coarse particles.
    Reference: Peters et al. (2005,
    0957471
    Also Peters et al, 2005 (2005,1568591
    
    Period of Study: Feb 1999-Jul 2001
    
    Location: Augsburg, Germany
    Outcome: Myocardial infarction
    
    Study Design: Case-crossover
    
    N: 691 myocardial infarction patients
    
    Statistical Analysis: Conditional
    logistic regression
    
    Dose-response Investigated? No
    Pollutant: Ultrafme (TNC) (n/cm3)
    
    Averaging Time: 1 h: Median = 10,001
    
    IQR: 7919
    
    24-h: Median = 10,934
    
    IQR: 6276
    
    Copollutant: N02, S02, CO
    PM Increment: Effect Estimate:
    
    2-h lag: OR = 0.95
    
    95% Cl: 0.84, 1.06
    
    24-h mean, 2-day lag: OR = 1.04
    
    95% Cl: 0.90, 1.20
    
    Notes: Examined triggering for Ml at
    various lags before Ml onset (up to 6 h
    before Ml,  up to 5 days  before Ml). No
    statistically significant increases in
    lagged ultrafme particle concentration
    were found.
    Reference: Ruckerl et al. (2007,
    0913791
    Period of Study: Oct 2000-Apr 2001
    
    Location: Erfurt, Germany
    Outcome (ICD9 and ICD10): Soluble
    CD40 ligand (sCD40L), platelets,
    leukocytes,  erythrocytes, hemoglobin
    
    Age Groups: 50+ yr
    
    Study Design: Panel (12 repeated
    measures at 2-wk intervals)
    
    N: 57  male subjects with coronary
    disease
    
    Statistical Analyses: Fixed effects
    linear  regression models
    
    Covariates: Long-term time trend,
    weekday of the visit, temperature, RH,
    barometric pressure
    
    Season: Time trend as covariate
    Pollutant: UFP
    
    Averaging Time: 24 h
    
    Mean (SD): 12,602 (6455)
    
    Percentiles:
    25th: 7326
    
    50th: 11,444
    
    75th: 17,332
    
    Range (Min, Max): 328, 4908
    
    Monitoring Stations: 1 site
    
    Copollutant:
    
    AP
    PM Increment: IQR (10,005
    
    5-day avg: 6,821)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    SCD40L, % change GM (pg/mL)
    lag 0:7.1 (0.1,14.5)
    lag 1:0.3 (-6.6, 8.6
    lag 2: 0.6 (-5.9, 8.6
    lag 3:-8.5 (-15.8,-0.5)
    5-day mean: -0.7 (-7.6, 6.8)
    Platelets, % change mean (103/ul)
    lag 0:-1.8 (-3.4,-0.2)
    lag 1:-1.1 (-2.9,0.6)
    lag 2:1.0 (-2.9, 0.8)
    lag 3: -2.4(4.5, -0.3)
    5-day mean: -2.2 (-4.0, -0.3)
    Leukocytes, [103/ul]
    lag 0: -2.4 (-4.5, -0.2)
    Dose-response Investigated? No
    Statistical Package: SAS v8.2 and S-
    piusve.o
    nvi25
    PM10
    NO
    lag 1: -2.1
    lag 2: -0.2
    lag 3: -1.5
    5-day mea
    -4.4, 0.2)
    -2.4, 2.8)
    -4.4, 1.4)
    r. -1.6 (-4.1, 0.8)
     All units expressed in pg/m unless otherwise specified.
    December 2009
                                     E-84
    

    -------
    E.1.2.Cardiovascular Emergency  Department Visits and  Hospital
    Admissions
    Table E-5.      Short-term exposure-cardiovascular: ED/HA PM
                                                                                  10
               Reference
                                           Design & Methods
            Concentrations
                                                                         Effect Estimates (95% Cl)
    Reference: Anderson et al. (2003,
    0548201
    Period of Study: 1992-1994
    Location: London, U.K.
                                     Outcome: Ischemic Heart Disease
                                     Age Groups: 0-15, 15-64, 65-74, 75+
                                     Study Design: Time series
                                     N:NR
                                     Statistical Analyses: NR
                                     Covariates: NR
                                     Dose-response Investigated? No
                                     Statistical Package: NR
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (min-max): NR
    Monitoring Stations: NR
    Copollutant: NR
                                                                     PM Increment: 10th-90th percentile
                                                                     % Change in Daily IHD Admissions
                                                                     byAge[CI]:0-15yr:NR
                                                                     15-64 yr: 2.6 [0.3,5]
                                                                     65-74 yr: 2.5 [0.1,4.9]
                                                                     75+ yr: 2.2 [0.2,4.6]
                                                                     Notes: RRs are presented in graph
                                                                     form showing little change with
                                                                     increasing age (PM increment of
                                                                     10 |jg/m3). This article is primarily a
                                                                     systematic literature review of other
                                                                     studies.
    Reference: Andersen et al. (2008,
    1896511
    Period of Study: May 2001-Dec 2004
    Location: Copenhagen, Denmark
                                                                     Pollutant: PM,,
    Outcome (ICD-10): CVD, including
    angina pectoris (I20), myocardial
    infarction (121-22), other acute ischemic  Averaging Time: 24 h
    heart diseases (I24), chronic ischemic
    heart disease (I25), pulmonary
    embolism (I26), cardiac arrest (I46),
    cardiac arrhythmias (148-48), and heart
    failure (ISO).
                                                                     ..„„ ,.ra. ,,,,,>
                                                                     Mean ' 24<14'
                                                                     Median: 21
                                                                     IQR: 16-28
                                     Age Groups: >65 yr (CVD and RD),
                                     5-18 yr (asthma)
                                     Study Design: Time series
                                     N:NR
                                     Statistical Analyses: Poisson GAM
                                     Covariates: Temperature, dew-point
                                     temperature, long-term trend,
                                     seasonally, influenza, day of the week,
                                     public holidays.
                                     Season: NR
                                     Dose-response Investigated: No
                                     Statistical Package: R (gam
                                     procedure, mgcv package)
                                     Lags Considered: Lag 0 -5 days, 4-
                                     day pollutant avg (lag 0 -3) for CVD.
                                                                     99th percentile): 72
                                                                     Monitoring Stations: 1
                                                                     Copollutant (correlation):
                                                                     NCtot:r = 0.39
                                                                     NC100:r = 0.28
                                                                     NCa12:r = 0.02
                                                                     NCa23:r = -0.12
                                                                     NCa57:r = 0.45
                                                                     NCa212:r = 0.63
                                                                     PM25:r = 0.80
                                                                     CO: r = 0.37
                                                                     N02:r = 0.35
                                                                     N0x:r = 0.32
                                                                     N0xcurbside:r = 0.18
                                                                     03:r = -0.21
                                                                     Other variables:
                                                                     Temperature: r = 0.12
                                                                     Relative humidity: r = 0.05
                                     PM Increment: 13 pg/m3 (IQR)
                                     Relative risk (RR) Estimate [Cl]:
                                     CVD hospital admissions
                                     (4-day avg, lag 0 -3), age 65+:
                                     One-pollutant model: 1.03 [1.01-1.05]
                                     Adj for NCtot: 1.04 [1.02-1.06]
                                     Adj for NCa212:1.05 [1.01-1.09]
                                     RD hospital admissions
                                     (5-day avg, lag 0 -4), age 65+:
                                     One-pollutant model: 1.06 [1.02-1.09]
                                     Adj for NCtot: 1.05 [1.01-1.10]
                                     Adj for NCa212:1.04 [0.98-1.11]
                                     Asthma hospital admissions
                                     (6-day avg lag 0-5), age 5-18:
                                     One-pollutant model: 1.02 [0.93-1.12]
                                     Adj for NCtot: 1.01 [0.91-1.12]
                                     Adj for NCa212: 0.94 [0.81-1.09]
                                     Estimates for individual day lags
                                     reported only in Fig form (see notes):
                                     Notes: Fig 2: Relative risks and 95%
                                     confidence intervals per IQR in single
                                     day concentration (0- to 5-day lag).
                                     Summary of Fig 2: CVD: Positive,
                                     marginally or statistically significant
                                     associations at Lag 0-Lag  2.
    December 2009
                                                                   E-85
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Anderson et al. (2007,
    1562141
    
    Period of Study: January
    1999-December2004
    
    Location: Copenhagen, Denmark
    Outcome (ICD10): Hospital Admission,
    CVD, including angina pectoris (I20),
    myocardial infarction (121-22), other
    acute ischemic heart diseases (I24),
    chronic ischaemic heart disease (I25),
    pulmonary embolism (I26), cardiac
    arrest (I46), cardiac arrhythmias
    (148-48), and heart failure (ISO).
    
    Age Groups Analyzed: Age >65
    
    Study Design: Time series
    
    N: 2192 days, 9 Hospitals
    
    Statistical Analyses: Principal
    Component Analysis and Constrained
    Physical Receptor Model (COPREM),
    Poisson regression, GAM,
    
    Covariates: Season, day of the wk,
    public holidays, influenza epidemics
    and meteorology
    
    Season: All yr
    
    Dose-response Investigated?  No
    
    Statistical package: R, gam/mgcv
    package
    
    Lags Considered: 0-6 days
    Pollutant: Source specific PMi0
    components
    
    Averaging Time: 24 h
    
    Mean (SD): Percentiles:
    25th: 16
    
    50th (Median): NR
    
    75th: 30
    
    Monitoring Stations: 1
    Copollutant (correlation):
    PM10:
    Biomass: r = 0.53
    Secondary: r = 0.73
    Oil: r = 0.57
    Crustal:r = 0.37
    Sea salt: r = 0.04
    Vehicle: r = 0.02
    Notes: Correlations between source
    specific PM10 components presented in
    paper
    PM Increment: IQR
    
    RR Estimate
    
    Respiratory disease (age >66)
    
    Single pollutant model:
    
    PM10:1.027 (1.013, 1.042), IQR=14
    
    PM,o (other 5 sources):  1.045 (1.016,
    1.074),  IQR=13
    
    Biomass: 1.040 (0.009,  1.072), IQR=5.4
    
    Secondary: 1.050 (1.021,1.081),
    IQR=6.1
    
    011:1.035(1.006,  1.065), IQR=2.8
    
    Crustal: 1.054 (1.028, 1.081), IQR=1.8
    
    Sea salt: 0.98 (0.947, 1.017), IQR=2.2
    
    Vehicle: 0.989 (0.949, 1.032), IQR=0.6
    
    Notes:  2 pollutant model results for
    PMio with source specific components
    and gases also presented in
    manuscript.
    Reference: Baccarelli et al. (2007,
    0913101
    Period of Study: Jan 1995-Aug 2005
    
    Location: Lombardia region, Italy
    Outcome (ICD9 and ICD10): Fasting
    and postmethionine-load total
    homocysteine (tHcy)
    
    Age Groups: 11-84yr
    
    Study Design: Cross-sectional/Panel
    
    N: 1,213 participants
    
    Statistical Analyses: Generalized
    additive models
    
    Covariates: age, sex, BMI, smoking,
    alcohol, hormone use, temperature, day
    of the yr, and long-term trends
    
    Season: Adjusted for long-term trends
    to account for season
    
    Dose-response Investigated? No
    
    Statistical Package: R software v2.2.1
    Pollutant: PM10 (some TSP measures
    used to predict PMio)
    
    Averaging Time: Hourly concentrations
    used to calculate 24-h ma and 7-day
    ma
    
    Mean (SD): NR
    
    Percentiles:
    25th: 20.1
    
    50th: 34.1
    
    75th: 52.6
    
    Range (Min, Max): Max: 390.0
    
    Monitoring Stations: 53 sites
    
    Copollutant:
    CO
    N02
    S02
    03
    PM Increment: IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Estimates (%) per 32.5 pg/m3 increase
    in 24-h maofPM10
    
    Homocysteine, fasting: 0.4 (-2.4, 3.3)
    
    Homocysteine, postmethionine-load:
    (-1.5,3.7)
    
    Estimates (%) per 25.7m3 increase in 7-
    day maof PMio
    
    Homocysteine, fasting: 1.0 (-1.9, 3.9)
    
    Homocysteine, postmethionine-load:
    2.0 (-0.6, 4.7)
    
    Estimates of effect (%) on fasting
    homocysteine per IQR increase in 24-h
    PM,o levels
    
    Among smokers: 6.2 (0.0,12.7)
    
    Among non-smokers: -1.6 (-5.5, 2.5)
    
    Estimates of effect (%) on
    postmethionine-load homocysteine per
    IQR increase in 24-h PMio levels
    
    Among smokers: 6.0 (0.5,11.8)
    
    Among non-smokers: -0.1 (-3.6, 3.5)
    December 2009
                                     E-86
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ballester et al. (2006,
    0887461
    
    Period of Study: 1995-1999
    
    Location: 5 Spanish cities: Granada,
    Huelva, Madrid, Seville, Zaragoza
    Outcome (ICD-9): All cardiovascular
    disease (390-459), including all heart
    diseases (410-414, 427, 428)
    
    Age Groups: All ages
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Poisson GAMs
    
    Covariates: Dilytemp, barometric
    pressure relative humidity
    
    Daily influenza  incidence, day of the
    week, holidays, unusual events (ex.
    medical strikes), seasonal variation,
    trend
    
    Dose-response Investigated: No
    
    Statistical Package: S-Plus GAM
    function
    
    Lags Considered: lag 0-3 days, lag
    0-1  avg
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (10-90th percentile): overall
    mean NR.
    
    City specific means
    
    Granada: 43.2 (24.8, 62.6)
    
    Huelva: 38.6 (23.1, 57.3)
    
    Madrid: 35.7 (21.4, 54.4)
    
    Seville: 41.9  (27.3, 57.6)
    
    Zaragoza: 32.8 (17.3, 50.3)
    
    Monitoring Stations: At least three
    stations/city  (15+)
    
    Copollutant (correlation): Summary of
    the correlation coefficients between
    each pair of pollutants within cities:
    BS:r = 0.48
    
    TSP: N/A
    
    N02: from r = 0.13tor = 0.62
    (median r = 0.40)
    
    S02: from r = 0.20tor = 0.51
    (median r = 0.46)
    
    CO: from r = 0.34 to r = 0.45
    (median r = 0.37)
    
    03:from r = -0.07 to r = 0.16
    (median r = 0.11)
    PM Increment: 10 pg/m
    
    Relative risk [Cl]: Relative risks are
    expressed only in the form of figures
    (see notes).
    
    Percentage change in risk [Cl]: All
    cardiovascular diseases (avg of lags 0 -
    1): 0.91% [0.35,  1.47]
    
    Heart disease (avg of lags 0 -1)
    
    1.56% [0.82, 2.31]
    
    Notes: Relative risks for the single
    pollutant models are expressed in
    Fig 2.
    
    Fig 2: Time sequence of the combined
    association between PM10 and hospital
    admissions for all CVD (A) and heart
    disease (B).
    
    Summary of results: Significant, positive
    association of PMi0 with both overall
    CVD and heart disease hospitalizations
    at Lag 0 and Lag 1.
    
    Relative risks for 2 pollutant models
    are expressed in Fig 3: Fig 3:
    Combined  estimates of the association
    between hospital admissions for heart
    diseases and air pollutants (avg of lags
    0-1
    
    Adjusted for CO, N02, 03, orS02)
    
    Summary of results: Significant, positive
    association remains after adjusting for
    pollutants.
    December 2009
                                     E-87
    

    -------
                Reference
           Design & Methods
             Concentrations1
        Effect Estimates (95%  Cl)
    Reference: Bell et al. (2008, 0912681
    
    Period of Study: 1995-2002
    
    Location: Taipei, Taiwan
    Outcome (ICD-9): Hospital admissions
    for ischemic heart disease (410, 411,
    414), cerebrovascular disease
    (430-437).
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 6,909 hospital admissions for
    ischaemic heart diseases, 11,466 for
    cerebrovascular disease.
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Day of the week, time,
    apparent temperature, long-term trends,
    seasonality
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: NR
    
    Lags Considered: lags 0-3 days, avg
    of lags 0-3
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (range
    
    IQR):
    49.1  (127-215.5
    
    27.6)
    
    Monitoring Stations: Taipei area: 13
    monitors
    
    Taipei City: 5 monitors
    
    Monitors with correlations of 0.75 + for
    PMi0:12 monitors
    
    Copollutant: NR
    PM Increment: 28 pg/m  (near IQR)
    
    Percentage increase estimate [96%
    Cl]: Ischemic heart disease: Taipei
    area (13 monitors): LO: 1.91 (-1.25,
    5.17)
    L1:0.39 (-2.73, 3.61)
    L2:1.80 (-1.33, 5.04)
    L3:2.01 (-1.14,5.26)
    LOS: 2.91 (-1.52, 7.55)
    Taipei City (5 monitors): LO: 2.08 (-1.04,
    5.30)
    L1: 0.43 (-2.64, 3.60)
    L2: 2.17 (-0.92, 5.36)
    L3: 2.16 (-0.94, 5.36)
    LOS: 3.40 (-1.19, 8.20)
    Monitors with > = 0.75 between monitor
    correlations (12 monitors): LO: 1.82
    (-1.29,5.03)
    L1: 0.35 (-2.72, 3.52)
    L2:1.93 (-1.15, 5.10)
    L3:1.93 (-1.16, 5.12)
    LOS: 2.86 (-1.63, 7.54)
    Cerebrovascular disease: Taipei area
    (13 monitors):  LO:-1.41 (-3.80,1.04)
    L1:-1.95 (4.31, 0.48)
    L2: 0.77 (-1.62, 3.23)
    L3: 2.64 (0.21, 5.12)
    LOS: 0.01 (-3.33, 3.47)
    Taipei City (5 monitors): LO: -1.27
    (-3.64,  1.16)
    L1:-2.13 (-4.47, 0.27)
    L2: 0.85 (-1.52, 3.28)
    L3: 2.52 (0.13, 4.97)
    LOS: -0.07 (-3.53, 3.51)
    Monitors with > = 0.75 between monitor
    correlations (12 monitors): LO: -1.34
    (-3.70,1.07)
    L1:-1.98 (-4.31, 0.40)
    L2: 0.80 (-1.56, 3.22)
    L3: 2.61 (0.22, 5.05)
    L03: -0.02 (-3.40, 3.49)	
    Reference: Chan et al. (2007,1477871  Outcome: Cerebrovascular Emergency  Pollutant: PM10
    
    Period of Study: Apr 1997-Dec 2002   Adm lsslons
                                        Age Groups: 50+ yr
    Location: Boston, MA
                                        Study Design: Tme series
    
                                        Statistical Analyses: GAM Poisosn
                                        Regression
    
                                        Covariates: Yr, mo, day of wk,
                                        temperature, dew point
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: NR
    
                                        Lags Considered: 0-3 days
                                        Averaging Time: 24 h
    
                                        Mean (SD): 50.2 (22.1)
    
                                        Min:16.0
    
                                        Max: 325.4
    
                                        IQR: 25.4
    
                                        Monitoring Stations: 16
    
                                        Copollutant: 03, CO, S02, N02, PM25
    
                                        Co-pollutant Correlation:
    
                                        03: 0.43
    
                                        CO: 0.47
    
                                        S02: 0.59
    
                                        N02: 0.64
    
                                        PM25: 0.61
                                         PM Increment: Interquartile Range
                                         (25.4 pg/m3)
    
                                         Percent Change (Lower Cl, Upper Cl),
                                         p-value:
                                         Cerebrovascular Disease
                                         Lag 0:1.001 (0.969, 1.033)
                                         Lag 1:0.999 (0.9787, 1.020)
                                         Lag 2:1.023 (0.989, 1.057)
                                         Lag 3:1.030 (1.011,1.049)
                                         Lag 3+ 03:1.018  (0.987, 1.049)
                                         Lag 3 + 00:1.019(0.988, 1.050)
                                         Lag 3+ 03+ 00:1.015(0.985,  1.045)
    
                                         Stroke
                                         Lag 0: 0.969 (0.897, 1.041)
                                         Lag 1:0.992 (0.918, 1.066)
                                         Lag 2:1.004 (0.993, 1.015)
                                         Lag 3:1.009 (0.988, 1.030)
    
                                         Ischaemic stroke
                                         Lag 0: 0.984 (0.932, 1.036)
                                         Lag 1:0.993 (0.939, 1.047)
                                         Lag 2: 0.989 (0.927, 1.041)
                                         Lag 3:1.042 (0.981, 1.103)
    
                                         Haemorrhagic stroke
                                         Lag 0: 0.966 (0.884, 1.048)
                                         Lag 1:0.990 (0.908, 1.072)
                                         Lag 2:1.002 (0.920, 1.084)
                                         Lag 3: 0.974 (0.902, 1.046)	
    December 2009
                                     E-88
    

    -------
    Reference
    Reference: Chan et al. (2008, 0932971
    Period of Study: 1995-2002
    Location: Taipei Metropolitan area,
    Taiwan
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Chang et al. (2007,
    1476211
    
    Period of Study: 1997-2001
    Location: Taipei, Taiwan
    
    
    
    
    
    
    
    
    Reference: D'lppoliti et al. (2003,
    0743111
    
    Period of Study: Jan 1995-Jun 1997
    Location: Rorne Italy
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome (ICD-9): Emergency visits for
    ischaemic heart diseases (410-411,
    414), cerebrovascular diseases
    (430-437), and COPD (493, 496)
    Age Groups: All
    Study Design: Time series
    N:NR
    Statistical Analyses: Poisson
    regression models
    Covariates: Yr, mo, day of wk,
    temperature, dew point temperature,
    PM2.5, N02
    Season: All
    Dose-response Investigated: No
    Statistical Package: SAS version 8.0
    Lags Considered: 0- to 7-day lags
    Outcome: CVD HA
    
    Age Groups: NR
    Study Design: Case-crossover
    Statistical Analyses: Conditional
    Logistic Regression
    
    Covariates: Temperature, humidity
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: 0-2 days
    
    
    Outcome: Myocardial Infarction HA
    
    Age Groups: 18+yr
    Study Design: Case-crossover
    
    Statistical Analyses: Conditional
    Logistic Regression
    Covariates: Temperature, humidity
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: 0-4 days
    
    
    
    
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): High dust events: Pre-dust
    periods: 45.5 (17.6)
    Asian dust events: 122.7 (24.4)
    Low dust events: Pre-dust periods: 59.4
    (31.0)
    Asian dust events: 61.1 (17.8)
    Monitoring Stations: 1
    
    Copollutant: NR
    
    
    
    
    
    Pollutant: PM10
    
    Averaging Time: 24 h
    Mean: 48.32
    Min: 14.44
    
    26th: 32.65
    
    60th: 42.80
    76th: 57. 16
    Max: 234.91
    Monitoring Stations: 6
    Copollutant: 03, CO, S02, N02
    Co-pollutant Correlation: NR
    Pollutant: TSP
    
    Averaging Time: 24 h
    Mean (SD): 66.9 (19.7)
    
    26th: 54.7
    60th: 66.4
    
    76th: 78.4
    IQR: 23.7
    Monitoring Stations: 3
    Copollutant: CO, S02, N02
    Co-pollutant Correlation:
    CO: 0.35
    S02: 0.29
    N02: 0.38
    Effect Estimates (95% Cl)
    PM Increment: 25.4 pg/m3 (IQR)
    OR [96% Cl]: In environmental
    conditions without dust storms (results
    only shown for best-fitting model)
    Lag 3 days: 1.023 (1.003, 1.041)
    
    
    
    
    
    
    
    
    
    
    
    PM Increment: Interquartile Range
    (24.51 pg/m3)
    
    Odds Ratio (Lower Cl, Upper Cl):
    ion°p
    ŁzU U
    PM,0: 1.085 (1.061, 1.110)
    PM10+S02: 1.131 (1.103, 1.161)
    PM10+N02: 10.977 (0.950, 1.006)
    PM,o+ CO: 1.025 (0.999, 1.052)
    PM10+03: 1.064 (1.039, 1.090)
    <20°C
    PM,0: 1.142 (1.105, 1.180)
    PM10+S02: 1.235 (1.184, 1.288)
    PM,o+N02: 1.148 (1.103, 1.194)
    PM10+ CO: 1.165 (1.121, 1.212)
    PM10+03: 1.142 (1.105, 1.180)
    
    PM Increment: Quartiles
    
    Odds Ratio (Lower Cl, Upper Cl):
    Lag 0-2-day avg
    f-\i. A n lrc.f\
    ui. i.u (ret)
    011:1.048(0.957, 1.148)
    Qlll: 1.105(1.007, 1.214)
    QIV: 1.132 (1.023, 1.253)
    
    Various Lags
    Lag 0:1.023 (1.004, 1.042)
    Lag 1:1. 01 5 (0.996, 1.034)
    Lag 2: 1.017 (0.999, 1.035)
    Lag 3: 0.989 (0.974, 1.003)
    Lag 4: 1.001 (0.987, 1.016)
    
    
    
    
    December 2009
    E-89
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Fung et al, (2005, 0932621
    Period of Study:
    Nov1995-Dec2000
    Location: London, Ontario
    Outcome (ICD-9): Cardiovascular
    diseases
    (410-414, 427-428)
    Age Groups: <65 yr, 65+ yr
    Study Design: Time series
    N: 12,947 CVD admissions
    Statistical Analyses: GAM with locally
    weighted regression smoothers
    (LOESS)
    Covariates:  Maximum and minimum
    temp, humidity, day of the week,
    seasonal cycles, secular trends
    Season: NR
    Dose-response Investigated? No
    Statistical Package: S-Plus
    Lags Considered: Current to 3-day
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (min-max): 38.0 (5-248)
    SD = 23.5
    Monitoring Stations: 4
    Copollutant (correlation):
    N02:r = 0.30
    S02:r = 0.24
    CO: r = 0.21
    03:r = 0.53
    COM: r = 0.29
    PM Increment: 26 pg/m
    % Change in Daily Admission [Cl]:
    Age <65
    Current day mean: 2.6 [-2.3,7.7]
    2-day mean:-1.2 [-7.2,5.1]
    3-day mean: -3 [-9.6,4]
    Age 65+
    Current day mean: 0.9 [-2.3,4.2]
    2-day mean: -0.9 [-4.8,3.2]
    3-day mean:-0.1 [-4.4,4.5]
    Reference: Hanigan et al. (2008,
    1565181
    Period of Study: 1996-2005
    (Apr-Nov of each yr)
    Location: Darwin, Australia
    Outcome: Daily emergency hospital
    admissions for total cardiovascular
    (ICD-9: 390-459
    ICD-10: IOO-I99), ischemic heart
    disease (ICD-9: 410-414
    ICD-10:120-I25).
    Age Groups: All
    Study Design: Time series
    N: 8,279 hospital admissions
    Statistical Analyses: Poisson
    generalized linear models
    Covariates:  Indigenous status, time in
    days, temperature, relative humidity,
    day of the week, influenza epidemics,
    change between ICD editions, holidays,
    yrly population
    Season: Apr-Nov (corresponding to the
    dry season)
    Dose-response Investigated? No
    Statistical Package: R version 2.3.1
    Lags Considered: 0-3
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD
    range): 21.2 (8.2
    55.2)
    Monitoring Stations: N/A (see notes)
    Copollutant: NR
    PM Increment: 10 pg/m
    Percent change [96% Cl]: Overall
    CVD: Lag 0 (indigenous): -3.78 [-13.4,
    6.91]
    Lag 0 (non-indigenous): -3.43 [-9.00,
    2.49]
    All unstratified associations either
    negative or zero and not statistically
    significant.
    All other results of stratified analysis (by
    indigenous status) reported in a Fig
    (see notes).
    Notes: Fig 3: Associations between
    hospitalizations for non-indigenous and
    indigenous people with estimated
    ambient PM10. Summary: Confidence
    intervals were wide, but indigenous
    people generally had stronger
    associations with PM10 than non-
    indigenous people. Daily PMi0 exposure
    levels were estimated for the population
    of the city from visibility data using a
    previously validated models.
    December 2009
                                     E-90
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Hanigan et al. (2008,
    1565181
    Period of Study: 1996-2005
    (Apr-Nov of each yr)
    Location: Darwin, Australia
    Outcome: Cardiorespiratory Disease
    HA (ICD 9: 390-519
    ICD10:IOO-99SJOO-99)
    Age Groups: NR
    Study Design: Time series
    N: 8279 events
    Statistical Analyses: poisson
    regression
    Covariates: Indigenous status, time in
    days, temperature, relative humidity,
    day of the week, influenza epidemics,
    change between ICD editions, holidays,
    yearly population
    Dose-response Investigated? No
    Statistical Package: R
    Lags Considered: lags 0-3
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): 21.2 (8.2)
    Range: 55.2
    Monitoring Stations: 2 (monitored &
    modeled)
    Copollutant: NR
    Co-pollutant Correlation: N/A
    PM Increment: 10 pg/m
    Percent Change (Lower Cl, Upper Cl),
    lag:
    Tot. Cardiovascular, Indigenous: -3.43 (-
    9.00, 2.49), lag 0
    Tot Cardiovascular, Non-Indigenous: -
    3.78 (-13.4, 6.91), lag 0
    *Fig 3. percent change in hospital
    admissions per 10 pg/m3 increase in
    PM10
    Reference: Henrotin et al. (2007,
    0932701
    Period of Study: Mar 1994-Dec 2004
    Location: Dijon, France
    Outcome: Ischemic and hemorrhagic
    strokes
    Age Groups: All
    Study Design: Bi-directional case-
    crossover
    N: 1487 (ischemic) and 220
    (hemorrhagic) stroke patients
    Statistical Analyses: Conditional
    logistic regression
    Covariates: Temperature, relative
    humidity, influenza epidemics, holidays
    Season: NR
    Dose-response Investigated? Yes
    Statistical Package: STATA software v.
    8.2
    Lags Considered: 0-3 days
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (min-max):
    21.1 (2-103)
    SD=11.3
    Monitoring Stations: 1
    Copollutant: NR
    PM Increment: 10 pg/m3
    OR Estimate [Cl]: Ischemic stroke
    Same-day lag: 1.009 [0.930,1.094]
    1-day lag: 1.011 [0.998,1.094]
    2-day lag: 0.960 [0.889,1.036]
    3-day lag: 0.990 [0.919,1.066]
    Hemorrhagic stroke
    Same-day lag: 0.901 [0.730,1.111]
    1-day lag: 1.014 [0.828,1.241]
    2-day lag: 1.100 [0.903,1.339]
    3-day lag: 0.991 [0.881,1.212]
    Notes: Ischemic stroke ORswere also
    categorized into male and female,
    yielding similar results (none were
    significant for any lag days).
    Reference: Issever et al. (2005,
    0977361
    Period of Study:
    Jan1997-Dec2001
    Location: Istanbul, Turkey
    Outcome: Acute coronary syndrome
    (ACS)
    Age Groups: All
    Study Design: Time series
    N: 2889 ACS admissions
    Statistical Analyses: Multiple stepwise
    regression, Pearson correlation
    Covariates: Humidity, temperature,
    pressure
    Season: NR
    Dose-response Investigated?  No
    Pollutant: PM10
    Averaging Time: 24 h
    Mean: NR
    Monitoring Stations: 1
    Copollutant (correlation):
    ACS: r = 0.37 (p = 0.003)
    ACS controlled for temp: r = 0.29
    (p = 0.02)
    PM Increment: NR
    RR Estimate [Cl]: NR
    Notes: This study focused more on the
    seasonal change in acute coronary
    syndrome admissions.
    December 2009
                                     E-91
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Jalaludin et al. (2006,
    1894161
    
    Period of Study: Jan 1997-Dec 2001
    
    Location: Sydney, Australia
    Outcome (ICD-9): Cardiovascular
    disease (390-459), cardiac disease
    (390-429), ischemic heart disease
    (410-413) and cerebrovascular disease
    or stroke (430-438)
    
    Age Groups: 65+ yr
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: GAM, GLM
    
    Covariates: Temperature, humidity
    
    Season: Warm (Nov-Apr) and cool
    (May-Oct)
    
    Dose-response Investigated? No
    
    Statistical Package: S-Plus
    
    Lags Considered: 0-3
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (min-max): 16.8 (3.8-103.9)
    
    SD = 7.2
    
    Monitoring Stations: 14
    Copollutant (correlation):
    
    Warm
    BSP:r = 0.82
    PM25:r = 0.89
    03:r = 0.59
    N02:r = 0.44;
    CO: r  = 0.31
    S02:r = 0.37
    
    Cool
    BSP:r = 0.75
    PM25:r = 0.88
    03:r = 0.22
    N02:r = 0.67
    CO: r  = 0.48
    S02:r = 0.46
    
    Other variables:
    Warm
    Temp: r = 0.36
    Pel humidity: r = -0.25
    
    Cool
    Temp: r = 0.13
    Pel humidity: r = 0.05
    PM Increment: 7.8 pg/rri  (IQR)
    
    Percent Change Estimate [Cl]:
    All CVD
    Same-day lag: 0.72 [-0.14,1.60]
    Avg 0-1 day lag: 0.25
    [-0.61,1.12]
    Cool (same-day lag): 1.34 [0.08,2.61]
    Warm (same-day lag): 0.33 [-0.83,1.50]
    Cardiac disease
    Same-day lag: 1.15 [0.14,2.18]
    Avg 0-1 day lag: 0.97
    [-0.07,2.02]
    Cool (same-day lag): 1.35 [-0.16,2.89]
    Warm (same-day lag): 1.12 [-0.23,2.48]
    Ischemic heart disease
    Same-day lag: 0.59 [-0.95,2.17]
    Avg 0-1 day lag: 0.61
    [-0.95,2.20]
    Cool (same-day lag): 0.33 [-2.00,2.72]
    Warm (same-day lag): 0.79 [-1.23,2.85]
    Stroke
    Same-day lag: -1.66 [-3.48,0.20]
    Avg 0-1 day lag: -2.05
    [-3.88.-0.20]
    Cool (same-day lag): 0.46 [-2.17,3.17]
    Warm (same-day lag): -3.49 [-5.97,-
    0.95]
    Notes: All other lag-day ORs were
    provided, yet none were significant.
    Percent change in ED attendance was
    also reported graphically
    
    (Fig 1-5).
    Reference: Johnston et al. (2007,
    1558821
    Period of Study: 2000, 2004, 2005
    (Apr-Nov of each yr)
    
    Location: Darwin, Australia
    Outcome (ICD-10): All cardiovascular
    conditions (IOO-I99), including ischemic
    heart disease (I20-I25).
    
    Age Groups: All
    
    Study Design: Case-crossover
    
    N: 2466 emergency admissions
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Wsekly influenza rates,
    temperature, humidity, days with rainfall
    >5mm, public holidays, school holiday
    periods (for respiratory conditions only)
    
    Season: Apr-Nov (dry season)
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 0-3
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Median: 17.4
    
    IQR: 13.6-22.3
    
    10-90th Percentile: 10.3-27.7
    
    Range: 1.1-70.0
    
    Monitoring Stations: 1
    
    Copollutant: NR
    PM Increment: 10 pg/m
    
    OR Estimate [96% Cl]: All respiratory
    conditions: Ischemic heart disease:
    Lag 0: 0.82 [0.68-0.98]
    
    Lag 0 (non-indigenous): 0.75
    [0.61-0.93]
    
    Lag 3 (indigenous): 1.71  [1.14-2.55]
    
    Notes:
    
    Fig 6: OR and 95% Cl for hospital
    admissions for cardiovascular
    conditions.
    
    Summary: Negative associations in
    overall study population and in non-
    indigenous people. Positive
    associations in Indigenous people at
    Lag 1, Lag 2, and Lag 3.
    
    Fig 6: OR and 95% Cl for hospital
    admissions for ischaemic heart disease.
    
    Summary: Negative associations in
    overall study population and non-
    indigenous people. Positive association
    in indigenous people.
    December 2009
                                     E-92
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Koken et al. (2003,
    0494661
    
    Period of Study: Jul and Aug,
    1993-1997
    
    Location: Denver, Colorado
    Outcome (ICD-9): Acute myocardial
    infarction (410.00-410.92), pulmonary
    heart disease (416.0-416.9), cardiac
    dysrhythmias (427.0-427.9), congestive
    heart failure (428.0)
    
    Age Groups: 65+ yr
    
    Study Design: Time series
    
    N: 298 days
    
    Statistical Analyses: GLM, GEE
    
    Covariates: Maximum temp and dew
    point temp
    
    Season: NR
    
    Dose-response Investigated: Yes
    
    Statistical Package: SAS (PROC
    GENMOD)
    
    Lags Considered: 0-4 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (min-max): 24.2 (7.0-51.6)
    
    SD = 6.25
    
    Monitoring Stations: 3
    
    Copollutant (correlation):
    N02:r = 0.56
    
    S02:r = 0.36
    
    03:r = 0.03
    
    CO: r = 0.25
    
    Other variables: Max temp: r = 0.38
    
    Dew point temp: r = -0.24
    PM Increment: 8.0 pg/m  (IQR)
    
    Percent Change Estimate [Cl]: No PM
    data reported
    Reference: Lanki et al, (2006, 0897881
    
    Period of Study: 1992-2000
    
    Location:
    Augsburg,  Barcelona, Helsinki, Rome,
    and Stockholm
    Outcome (ICD-9): Acute myocardial
    infarction
    
    (410
    
    ICD-10:121,122)
    
    Age Groups: 35+ yr, <75 yr, 75+ yr
    
    Study Design: Time series
    
    N: 26,854 hospitalizations
    
    Statistical Analyses: GAM
    
    Covariates: Temperature, barometric
    pressure
    
    Season: V\ferm (Apr-Sep) and cold
    (Oct-Mar)
    
    Dose-response Investigated: No
    
    Statistical Package: R package mgcv
    0.9-5
    
    Lags Considered: 0-3 days
    Pollutant: PM10
    
    Averaging Time: 24 h
    Median:
    Augsburg: 43.5
    Barcelona: 57.4
    Helsinki: 21.0
    Rome: 48.5
    Stockholm: 12.5
    Copollutant (correlation):
    
    Augsburg
    PNC: r = 0.53
    CO: r = 0.56
    N02:r = 0.64
    03:r = 0.43
    
    Barcelona: PNC: r = 0.38
    CO: r = 0.44
    N02:r = 0.48
    03:r = 0.01
    
    Helsinki: PNC: r = 0.45
    CO: r = 0.21
    N02:r = 0.40
    03:r = 0.40
    
    Rome: PNC: r = 0.32
    CO: r = 0.41
    N02:r = 0.29
    03:r = 0.59
    
    Stockholm: PNC: r = 0.06
    CO: r = 0.41
    N02:r = 0.29
    03:r = 0.59
    PM Increment: 10 pg/m
    Pooled Rate Ratio [Cl]:
    All 5 cities (35+ yr)
    Same-day lag: 1.003 [0.995,1.011]
    1-day lag: 1.001 [0.990,1.011]
    2-day lag: 1.002 0.994,1.010'
    3-day lag: 1.002 0.991,1.013
    3 cities with hospital discharge register
    (35+ yr)
    Same-day lag: 1.003 [0.994,1.012]
    1-day lag: 0.997 [0.988,1.006]
    2-day lag: 1.003       ' ""
                                                                                                               3-day lag: 1.003
    0.995,1.012
    0.986,1.020
                                                                                                               V\ferm season (35+ yr)
                                                                                                               Same-day lag: 1.006 [0.990,1.022]
                                                                                                               1-day lag: 1.000 [0.985,1.016]
                                                                                                               2-day lag: 1.005 [0.990,1.020]
                                                                                                               3-day lag: 1.010 [0.995,1.025]
                                                                                                               Cold season (35+ yr)
                                                                                                               Same-day lag: 1.001 [0.991,1.012]
                                                                                                               1-day lag: 0.998       ' ""
                                                                                                               2-day lag: 1.001
                   0.987,1.009
                   0.991,1.012
                                                                                                               3-day lag: 0.991 [0.981,1.002]
                                                                                                               Age >75
                                                                                                               Non-fatal
                                                                                                               Same-day lag: 1.012 [0.995,1.029]
                                                                                                               1-day lag: 1.000
                                                                                          0.983,1.017
                                                                                          0.982,1.017
                                                                                                               2-day lag: 0.999
                                                                                                               3-day lag: 1.001 [0.984,1.018]
                                                                                                               Fatal
                                                                                                               Same-day lag: 1.009 [0.985,1.034]
                                                                                                               1-day lag: 0.998 [0.974,1.023]
                                                                                                               2-day lag: 1.003
                                                                                                               3-day lag: 1.018
                                                                                          0.978,1.028
                                                                                          0.975,1.063
                                                                                                               Notes: Pooled rate ratios were also
                                                                                                               provided for groups <75 yielding similar
                                                                                                               results to the overall 3-city data.
    December 2009
                                     E-93
    

    -------
               Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Lee et al. (2003, 0955521
    Period of Study:
    Dec1997-Dec1999
    Location: Seoul, Korea
    Outcome (ICD-10): Angina pectoris
    (I20), acute/subsequent myocardial
    infarction (121-123), other acute
    ischemic heart diseases (124)
    Age Groups: All ages, 64+ yr
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): 64.0 (31.8)
    Monitoring Stations: 27
    PM Increment: 40.4 pg/rri (IQR)
    RR Estimate [Cl]: All yr
    All ages: 0.99 [0.96,1.01]
    64+yr: 1.05 [1.01,1.10]
    Summer
    Study Design: Time series
    N: 822 days
    Statistical Analyses: GAM with
    LOESS, Pearson correlation
    Covariates: Temperature, relative
    humidity, day of the week
    Season: Summer (Jun-Aug) and winter
    Dose-response Investigated: Yes
    Statistical Package: NR
    Lags Considered: 0-6 days
    Copollutant (correlation):
    Allyr
    S02:r = 0.59
    N02:r = 0.74
    03:r = 0.11
    CO: r = 0.60
    Temp: r = -0.07
    Humidity: r = 0.02
    Summer
    S02:r = 0.61
    N02:r = 0.73
    03:r = 0.64
    CO: r = 0.55
    Temp: r = -0.01
    Humidity: r = -0.11
    All ages: 1.03 [0.97,1. 09]
    64+ yr: 1.09 [1.00,1. 19]
    Two-pollutant model
    00(1 ppmlQI): 1.04 [0.98,1. 11]
    03 (21.7 ppblQI): 1.07 [1.03,1. 11]
    N02 (14.6 ppblQI): 1.09 [1.02,1. 16]
    S02 (4.4 ppb): 0.98 [0.94,1. 03]
    Reference: Lee et al. (2008,1920761
    Period of Study: 1996-2005
    Location: Taipei, Taiwan
    Outcome: Congestive Heart Failure HA
    (ICD9:428)
    Age Groups: NR
    Study Design: Case-crossover
    N: 18593 events
    Statistical Analyses: conditional
    logistic regression
    Covariates: Temperature, humidity
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: Lags 0-2
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean: 49.94
    Min: 11.33
    25th: 33.37
    60th: 45.05
    76th: 60.82
    Max: 234.92
    Monitoring Stations: 6
    Copollutant: S02, CO, N02, 03
    Co-pollutant Correlation
    PM Increment: Interquartile Range
    (27.45 pg/m3)
    Odds Ratio (Lower Cl, Upper Cl):
    VW Hypertension: 1.23 (1.15,1.32)
    W/o Hypertension: 1.20 (1.15,1.25)
    VW Diabetes: 1.20 (1.12,1.40)
    W/o Diabetes:  1.21 (1.15,1.26)
    W/Dysrhythmia: 1.17 (1.08,1.27)
    W/o Dysrhythmia: 1.22 (1.17,1.27)
    W/COPD:1.21 (1.07, 1.36)
    W/o COPD: 1.21 (1.16, 1.25)
    S02: 0.52
    CO: 0.67
    N02: 0.35
    03: 0.39
    Reference: Larrieu et al. (2007,
    0930311
    Period of Study: 1998-2003
    1 oration1
    LUUdllUII.
    8 French urban area: Bordeaux, Le
    Havre, Lille, Lyon, Marseille, Paris,
    Rouen, and Toulouse
    
    
    
    
    
    
    
    
    
    Outcome (ICD-10): Hospital
    admissions for cardiovascular disease
    (IOO-I99), cardiac disease (IOO-I52),
    ischemic heart disease (I20-I25), and
    stroke (cerebrovascular disease: 160-64
    and transient ischemic attack:
    G45-G46).
    Age Groups: All, and 65 +
    
    Study Design: Time series
    
    N: Statistical Analyses: generalized
    additive Poisson regression
    Covariates: Temperature, holidays,
    influenza epidemic periods, long-term
    trend, season, day of the week,
    Season: NR
    Dose-response Investigated: No
    Pollutant: PM10
    Averaging Time: 24 h
    Mean: Bordeaux: 21.0
    Le Havre: 21. 7
    Lille: 22.1
    Lyon: 24.6
    
    Marseille: 28.9
    
    Paris: 23.1
    Rouen: 21. 2
    Toulouse: 21.8
    Monitoring Stations: 32
    Copollutant: NR
    PM Increment: 10 pg/m3
    ERR[96%CI]:
    CVD: All ages: 0.7 [0.1, 1.2]
    65+ yr: 1.1 [0.5, 1.7]
    Cardiac diseases: All ages: 0.8 [0.2,
    1.4]
    
    65+ yr: 1.5 [0.7, 2.2]
    
    Ischemic heart diseases: All ages: 1.9
    [0.8, 3.0]
    65+ yr: 2.9 [1.5, 4.3]
    Strokes: All ages: 0.2 [-1.6, 1.9]
    65+ yr: 0.8 [-0.9, 2.5]
    
                                       Statistical Package: R 2.2.1
                                       Lags Considered: 0 -to 1-day lag
                                       (mean)
    December 2009
                                    E-94
    

    -------
    Reference
    Reference: Le Tertre et al. (2002,
    0237461
    Period of Study: 1990-1997
    Location:
    Barcelona, Birmingham, London, Milan,
    the Netherlands, Paris, Rome, and
    Stockholm
    
    
    
    
    
    
    
    Design & Methods
    Outcome (ICD-9): Cardiac diseases
    (390-429), ischemic heart disease (410-
    413), and stroke (430-438)
    Age Groups: <65 yr, 65+ yr
    Study Design: Time series
    N:NR
    Statistical Analyses: GAM
    Covariates: Long term trend, season,
    days of the week, holidays, influenza
    epidemics, temperature, and humidity
    Season: NR
    Dose-response Investigated: No
    Statistical Package: S-Plus
    Lags Considered: 0-3 days
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD):
    Barcelona: 55.7 (18. 4)
    Birmingham: 24.8 (13.1)
    London: 28.4 (12.3)
    Milan: 51. 5 (22.7)
    Netherlands: 39.5 (19.9)
    Paris: 22.7 (10.8)
    Rome: 52.5 (12.9)
    Stockholm: 15.5 (7.2)
    Monitoring Stations: 1-12
    Copollutant: NR
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    Pooled Percent Increase [Cl]: Cardiac
    (all ages)
    Fixed: 0.5 [0.3,0.7]
    Random: 0.5 [0.2,0.8]
    Cardiac (over 65)
    Fixed: 0.7 [0.4,1.0]
    Random: 0.7 [0.4,1.0]
    IHD (<65)
    Fixed: 0.3 [-0.1, 0.6]
    Random: 0.3 [-0.2,0.7]
    IHD (over 65)
    Fixed: 0.6 [0.3,0.8]; Random: 0.8
                                                                                                                 [0.3,1.2]
    
                                                                                                                 Stroke (over 65)
    
                                                                                                                 Fixed: 0.0 [-0.3,0.3]; Random: 0.0 [-
                                                                                                                 0.3,0.3]
    
                                                                                                                 Deaths: Cardiac: 0.5 [0.2,0.8]; Cardiac
                                                                                                                 (65+): 0.7 [0.4,1.0]
    
                                                                                                                 IHD (65+): 0.8 [0.3,1.2]
    
                                                                                                                 Notes: Estimated percentage increases
                                                                                                                 are also provided by city for cardiac
                                                                                                                 admissions and ischemic heart disease
                                                                                                                 in Fig 1-3.
    Reference: Mann et al. (2002, 0367231  Outcome (ICD-9): Ischemic heart
                                        disease (410-414), secondary
    Period of Study: 1988-1995
    
    Location: South Coast Air Basin,
    California
    congestive heart failure (sCHF) (428),
    and secondary arrhythmia (sARR) (426,
    427)
    
    Age Groups: All, 40-59 yr, >60 yr
    
    Study Design: Time series
    
    N: 54,863 IHD admissions
    
    Statistical Analyses: GAM
    
    Covariates: Temperature, day of the
    week, relative humidity
    
    Season:  NR
    
    Dose-response Investigated:  No
    
    Statistical Package: S-Plus
    
    Lags Considered: 0-5 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (min-max): 43.7 (0.22-251)
    
    SD = 27.7
    
    Monitoring Stations: 20
    Copollutant (correlation):
    Region 1:
    CO: r = 0.28
    03:r = 0.20
    N02:r = 0.36
    Region 2:
    CO: r = 0.15
    03:r = 0.57
    N02:r = 0.53
    Region 3:
    CO: r = 0.36
    03:r = 0.30
    N02:r = 0.46
    Region 4:
    CO: r = 0.27
    03:r = 0.33
    N02:r = 0.50
    Region 5:
    CO: r = 0.40
    03:r = 0.43
    N02:r = 0.53
    Region 6:
    CO: r = 0.33
    03:r = 0.20
    N02:r = 0.42
    Region 7:
    CO: r = 0.28
    03:r = 0.48
    N02:r = 0.60
    PM Increment: 10 pg/m
    
    Percent Change in IHD Admissions
    [Cl]: Secondary ARR
    
    Same-day lag: 0.59 [-0.71,1.91]
    
    1-day lag: 0.46 [-0.86,1.80]
    
    2-day lag:-0.04 [-1.37,1.31]
    
    Secondary CHF
    
    Same-day lag:-0.62 [-1.77,0.55]
    
    1-day lag:-0.45 [-1.60,0.71]
    
    2-day lag:-0.36 [-1.52,0.82]
    
    No secondary diagnosis
    
    Same-day lag:-0.25 [-1.23,0.75]
    
    1-day lag: 0.04 [-0.97,1.06]
    
    2-day lag: 0.18 [-0.82,1.20]
    
    All IHD admissions: 0.19 [-0.576,0.955]
    
    Ml admissions:-0.10 [-1.33,1.12]
    
    Other acute IHD admissions: 0.36 [-
    0.87,1.60]
    December 2009
                                     E-95
    

    -------
                Reference
           Design & Methods
                                                 Concentrations1
                                            Effect Estimates (95% Cl)
    Reference: Metzger et al. (2004,
    0442221
    
    Period of Study: Aug 1993-Aug 2000
    
    Location: Atlanta Metropolitan area
    (Georgia)
    Outcome (ICD-9): Emergency visits for
    ischemic heart disease (410-414),
    cardiac dysrhythmias (427), cardiac
    arrest (427.5), congestive heart failure
    (428), peripheral vascular and
    cerebrovascular disease (433-437, 440,
    443.444, 451-453), atherosclerosis
    (440), and stroke  (436).
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 4,407,535 emergency department
    visits
    
    Statistical Analyses:  Poisson
    generalized linear modeling
    
    Covariates: Day  of the wk, hospital
    entry and exit indicator variables,
    federally observed holidays, temporal
    trends, temperature, dew point
    temperature
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: SAS
    
    Lags Considered: 3-day ma, lags 0 -7
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Median (10% - 90% range): 26.3 (13.2,
    44.7)
    
    Monitoring Stations: NR
    
    Copollutant (correlation):
    03:r = 0.59
    N02:r = 0.49
    CO: r  = 0.47
    S02:r = 0.20
    PM25:r = 0.84
    
    UFP:"2r5=-0.13
    PM2 5  water-sol
    metals: r = 0.74
    PM25sulfates:r = 0.74
    PM25  acidity: r = 0.68
    PM25OC:r = 0.69
    PM25EC:r = 0.56
    oxygenated hydrocarbon: r = 0.58
    
    Other variables: Temperature: r = 0.58
    Dew point: r = 0.44
                                                                             PM Increment: 10 pg/m
                                                                             (approximately 1 SD)
    
                                                                             RR [96% Cl]: For 3-day ma: All CVD:
                                                                             1.009 [0.998, 1.019]
    
                                                                             Dysrhythmia: 1.008 [0.989,1.029]
    
                                                                             Congestive heart failure: 0.992
                                                                             [0.968-1.016]
    
                                                                             Ischemic heart disease: 1.011
                                                                             [0.992-1.030]
    
                                                                             Peripheral vascular and
                                                                             cerebrovascular disease: 1.020
                                                                             [0.999-1.043]
    
                                                                             Notes: Results for Lags 0-7 expressed
                                                                             in figures
    
                                                                             Fig 1: RR (95% Cl) for single-day lag
                                                                             models for the association of ER visits
                                                                             for CVD  with daily ambient PMi0.
    
                                                                             Summary: Statistically significant
                                                                             association at Lag 0. Positive but not
                                                                             statistically significant association at
                                                                             Lag 1. Negative, statistically significant
                                                                             association at Lag 7, and negative
                                                                             associations at Lag 2 through Lag 6.
    Reference: Middleton et al. (2008,
    1567601
    Period of Study: 1995-1998,
    2000-2004
    
    Location: Nicosia, Cyprus
    Outcome: Hospital admissions for all
    cardiovascular disease (ICD-10:
    IOO-I52).
    
    Age Groups: All, also stratified by age
    (<15vs.. >15yr)
    
    Study Design: Time series
    
    Statistical Analyses: Generalized
    additive Poisson models
    
    Covariates: Seasonality, day of the
    week, long- and short-term trend,
    temperature, relative humidity
    
    Dose-response Investigated: No
    
    Statistical Package: STATASE 9.0, R
    2.2.0
    
    Lags Considered: Lag 0 -2 days
                                        Pollutant: PM,0
    
                                        Averaging Time: 24 h
    
                                        Mean (SD median 6% - 96% range):
                                        Cold: 57.6 (52.5
    
                                        50.8
    
                                        20.0-103.0
    
                                        5.0-1370.6)
    
                                        Warm: 53.4 (50.5
    
                                        30.7
    
                                        32.0-77.6
    
                                        18.4-933.5)
    
                                        Monitoring Stations: 2
    
                                        Copollutant: NR
                                        PM Increment: 10 pg/m , and across
                                        quartiles of increasing levels of PMi0
    
                                        Percentage increase estimate [Cl]:
                                        All age/sex groups (Lag 0): All
                                        admissions: 0.85 (0.55,1.15)
    
                                        Cardiovascular: 1.18 (-0.01, 2.37)
    
                                        Nicosia residents (Lag 0):
                                        Cardiovascular: 0.73 (-0.62, 2.09)
    
                                        Males (Lag 0): All admissions: 0.96
                                        (0.54, 1.39)
    
                                        Cardiovascular: 1.27 (-0.15, 2.72)
    
                                        Females (Lag 0): All admissions: 0.74
                                        (0.31,1.18)
    
                                        Cardiovascular: 0.99 (-1.11,3.14)
    
                                        Aged <16 yr (Lag 0): All admissions:
                                        0.47 (-0.13, 1.08)
    
                                        Aged >16 yr (Lag 0): All admissions:
                                        0.98(0.63,1.33)
    December 2009
                                     E-96
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Peel et al. (2007, 0904421
    
    Period of Study: Jan 1993-Aug 2000
    
    Location: Atlanta, GA
    Outcome (ICD-9): Ischemic heart
    disease (410-414), dysrhythmia (427),
    congestive heart failure (428),
    peripheral vascular and
    cerebrovascular disease (433-437, 440,
    443, 444, 451-453)
    
    Age Groups: All
    
    Study Design: Case-crossover
    
    N: 4,407,535 ED visits
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Avg temp and dew point
    temp
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: SASv. 9.1
    
    Lags Considered: 0-2 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): Daily levels: 27.9 (12.3)
    
    Diff in case and control-day avg: 9.1
    (7.5)
    
    Monitoring Stations: 1
    
    Copollutant: NR
    PM Increment: 10 pg/m
    
    OR Estimate [Cl]: All CVD: 1.010
    [1.000,1.020]
    IHD: 1.009 [0.991,1.027]
    Dysrhythmia: 1.011 [0.991,1.031]
    
    Peripheral/Cerebrovascular disease:
    1.017 [0.996,1.039]
    CHF: 1.001  [0.978,1.024]
    With comorbid hypertension
    IHD: 1.003 [0.973,1.034]
    Dysrhythmia: 1.037 [0.988,1.089]
    
    Peripheral/Cerebrovascular disease:
    1.024 [0.990,1.060]
    CHF: 1.041  [0.999,1.084]
    No comorbid hypertension
    IHD: 1.013 [0.991,1.036]
    Dysrhythmia: 1.006 [0.985,1.028]
    
    Peripheral/Cerebrovascular disease:
    1.013 [0.987,1.040]
    CHF: 0.982 [0.955,1.010]
    With comorbid diabetes
    IHD: 1.022 [0.979,1.067]
    Dysrhythmia: 1.049 [0.968,1.137]
    
    Peripheral/Cerebrovascular disease:
    1.016 [0.965,1.069]
    CHF: 1.029 [0.982,1.078]
    No comorbid diabetes
    IHD: 1.006 [0.987,1.026]
    Dysrhythmia: 1.009 [0.989,1.029]
    
    Peripheral/Cerebrovascular disease:
    1.018 [0.995,1.042]
    CHF: 0.992 [0.966,1.019]
    Wth comorbid COPD
    IHD: 0.981 [0.921,1.044]
    Dysrhythmia: 0.984 [0.889,1.088]
    
    Peripheral/Cerebrovascular disease:
    1.086 [0.998,1.181]
    CHF: 1.010 [0.954,1.069]
    No comorbid COPD
    IHD: 1.012 [0.993,1.031]
    Dysrhythmia: 1.012 [0.992,1.032]
    
    Peripheral/Cerebrovascular disease:
    1.013 [0.991,1.035]
    CHF: 0.999 [0.974,1.025]	
    Reference: Pope et al., (2006, 0912461
    
    Period of Study: 1994-2004
    
    Location: Wasatch Front area, Utah
    Outcome: Myocardial infarction or
    unstable angina (ICD codes not
    reported)
    
    Age Groups: All
    
    Study Design: Case-crossover
    
    N: 12,865 patients who underwent
    coronary arteriography
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature and dew
    point temperature
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: NR
    
    Lags Considered: 0- to 3-day lag, 2- to
    4-day lagged ma
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD maximum):
    Ogden: 28.5 (16.5
    
    163)
    
    SLC Hawthorne: 27.7 (17.4
    
    162)
    
    Provo/Orem, Lindom: 32.7 (21.1
    
    240)
    
    SLC AMC: 35.9 (20.4
    
    161)
    
    SLC North: 45.1(25.1
    
    199)
    
    Monitoring Stations: 5
    
    Copollutant: NR
    PM Increment: 10 pg/m
    
    Percent increase in risk [96% Cl]:
    Results summarized in Fig (see notes).
    
    Notes: Fig 1: Percent increase in risk
    (and 95% Cl) of acute coronary events
    associated with 10 pg/m3 of PM10 for
    different lag structures.
    
    Summary of Fig 1: Positive, statistically
    significant or marginally significant
    associations between association seen
    for Lag 0, Lag 1 and 2-, 3-, and 4-day
    ma. Non-statistically significant
    associations
    December 2009
                                     E-97
    

    -------
                Reference
           Design & Methods
            Concentrations1
                                           Effect Estimates (95% Cl)
    Reference: Santos et al. (2008,
    1920041
    
    Period of Study: Jan 1998-Aug 1999
    
    Location: Sao Paulo, Bazil
    Outcome: Cardiac Arrhythmia ER Visits
    (ICD 10:145-149)
    
    Age Groups: 17+yr
    
    Study Design: Time series
    
    N:3251 ER visits
    
    Statistical Analyses: Poisson
    
    Covariates: Temperature, humidity,
    seasonality
    
    Dose-response Investigated? Yes
    
    Statistical Package: S-Plus
    
    Lags Considered: Lags 0-13
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 48.64 (20.34)
    
    Min: 18.68
    
    Max: 137.76
    
    Monitoring Stations: 14
    
    Copollutant: S02, CO,  N02, 03
    
    Co-pollutant Correlation:
    S02: 0.675*
    CO: 0.580*
    N02: 0.781*
    03: 0.438*
    *p < 0.01	
                                        PM Increment: Interquartile Range
                                        (22.2 pg/m3)
    
                                        Percent Increase (Lower Cl, Upper
                                        Cl):
                                        PMio+N02,CO:-5.6 (-12.7, 2.1)
                                        PM10+CO:-1.1(-7.0, 5.1)
                                        PM10+N02:-2.4 (-9.4, 5.1)
                                        Fig 1. PM10 effects, reported as percent
                                        increase, on arrhythmia ER visits
                                        caused by interquartile range increases,
                                        lags 0-6.
    
                                        Fig 2. Relative risks and 95% Cl for
                                        arrhythmia ER visits according to the
                                        division of air pollutant daily
                                        concentrations in quintiles.
    Reference: Tolbert et al. (2007,
    0903161
    
    Period of Study: 1993-2004
    
    Location: Atlanta Metropolitan area,
    Georgia
    Outcome (ICD-9): Combined CVD
    group, including: Ischemic heart
    disease (410-414), cardiac
    dysrhythmias (427), congestive heart
    failure (428), and peripheral vascular
    and cardiovascular disease (433-437,
    440, 443-445,  and 451-453).
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 10,234,490 ER visits (283,360 and
    1,072,429 visits included in the CVD
    and RD groups, respectively)
    
    Statistical Analyses: Poisson
    generalized linear models
    
    Covariates: Long-term temporal trends,
    season (for  RD outcome), temperature,
    dew point, days of week, federal
    holidays, hospital entry and exit
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: SAS version 9.1
    
    Lags Considered: 3-day ma (lag 0-2)
    Pollutant: PM10
    
    Averaging Time: 24 h
    
    Mean (median
    
    IQR, range, 10th-90th percentiles):
    26.6 (24.8
    
    17.5-33.8
    
    0.5-98.4
    
    12.3-42.8)
    
    Monitoring Stations: NR
    Copollutant (correlation):
    03:r = 0.59
    N02:r = 0.53
    CO: r = 0.51
    S02:r = 0.21
    Coarse PM:r = 0.67
    PM25:r = 0.84
    PM25S04:r = 0.69
    PM25EC:r = 0.61
    PM25OC:r = 0.65
    PM25TC:r = 0.67
    P M2 5 water-sol metals: r = 0.73
    OHC:r = 0.53
                                        PM Increment: 16.30 pg/rri  (IQR)
    
                                        Risk ratio [96% Cl]: Single pollutant
                                        models: CVD: 1.008 (0.997-1.020)
    Reference: Tsai et al. (2003, 0801331
    
    Period of Study: 1997-2000
    
    Location: Kaohsiung, Taiwan
    Outcome (ICD-9): Cerebrovascular
    diseases (430-438), subarachnoid
    hemorrhagic stroke (430), primary
    intracerebral hemorrhage (431-432),
    ischemic stroke (433-435), and others
    (436-438)
    
    Age Groups: All
    
    Study Design: Case-crossover
    
    N: 23,179 admissions
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature and humidity
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: SAS
    
    Lags Considered: Cumulative 0-2
    days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (min-max): 78.82 (20.50-217.33)
    
    Monitoring Stations: 6
    
    Copollutant: NR
                                        PM Increment: 66.33 pg/m3 (IQR)
    
                                        OR Estimate [Cl]: Two-pollutant
                                        model (all stroke admissions)
                                        Primary intracerebral hemorrhage (PIH)
                                        Adj for S02:1.55 [1.31,1.83]
                                        Adj for N02:1.28 [1.01,1.61];
                                        Adj for CO: 1.45 [1.20,1.74]
                                        Adj for 03:1.56 [1.27,1.91]
                                        Ischemic stroke (IS)
                                        Adj for S02:1.46 [1.32,1.61
                                        Adj for N02:1.16 [1.01,1.34
                                        Adj for CO: 1.35 [1.21,1.51]
                                        Adj for 03:1.51 [1.34,1.71]
                                        Single-pollutant model
                                        Temp >20°C
                                        PIH: 1.54 [1.31,1.81]
                                        IS: 1.46 [1.32,1.61]
                                        Temp <20°C
                                        PIH: 0.82 [0.48,1.40]
                                        IS: 0.97 [0.65,1.44]
    December 2009
                                     E-98
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Ulirsch et al. (2007,
    0913321
    Period of Study: Nov 1994-Mar 2000
    Location:
    Pocatello, Idaho and Chubbuck, Idaho
    Outcome (ICD-9): CVD (390-429).
    Age Groups: 65 +
    Study Design: Time series
    N: 39,347 admissions/visits
    Statistical Analyses: Log-linear
    generalized linear models
    Covariates: Time, temperature, relative
    humidity, influenza, day of the week
    Season: All, and separate analyses
    were performed for the all-age group for
    cool months (Oct-Mar) vs.. warm
    months (Apr-Sep).
    Dose-response Investigated: No
    Statistical Package: S-plus version 6.1
    Lags Considered: 0- to 4-day lags,
    and mean of days 0 -4
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (range 10th - 90th percentiles):
    24.2(3.0-183.0
    10.5-40.7)
    Monitoring Stations: 4
    Copollutant (correlation):
    N02:r = 0.47
    Other variables: Correlation for PM10
    between monitors: r = 0.42-0.87
    PM Increment: 50 pg/m  , and
    24.3 pg/m3 (mean increase in PM10)
    Mean percent of change (% change
    in the mean number of daily
    admissions and visits) [96% Cl]:
    For 24.3 pg/m3 increase in PM10:
    All-age  RD/CVD: 3.7 [1.3, 6.3]
                                                                                                              All-age CVD (Lag 0
                                                                                                              All-age CVD (Lag 1
                     : -0.02 [-5.9, 6.3]
                     : 1.9 [-4.1,8.4]
                                                                                                              All-age CVD (Lag 2):-3.1 [-9.1,3.4]
                                                                                                              All-age CVD (Lag 3
                     : 0.5 [-5.6, 6.9]
                     :-1.7 [-4.3, 0.9]
                                                                                                              All-age CVD (Lag 4 :
                                                                                                              Lag 0-4 days:-0.5 [-8.0, 7.6]
                                                                                                              For 60 ug/m3 increase in PM10
                                                                                                              (single pollutant models, CIs not
                                                                                                              given):
                                                                                                              All-age respiratory disease: 8.4
                                                                                                              All-age RD/CVD: 7.9
                                                                                                              18-64 yrRD: 7.2
                                                                                                              All-age CVD
                                                                                                              All-age CVD
                                                   Lag3
                                                   Lag 4
                     :-3.6
                                                                                                              All-age CVD (Lag 0-4):-1.1
                                                                                                              Notes: Included urgent care visits as
                                                                                                              well as emergency department visits
                                                                                                              and hospital admissions.
    Reference: Yang et al. (2007, 0928471  Outcome: Congestive Heart Failure HA
    Period of Study: 1996-2005           ('CD 9' 428)
    Location: Taipei, Taiwan
    Age Groups: NR
    Study Design: case-crossover
    N: 24,240 events
    Statistical Analyses: Poisson
    Covariates: Temperature, humidity
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: lags 0-3
    Pollutant: PM10
    Averaging Time: 24 h
    Mean: 49.47
    Min: 14.42
    26th: 33.08
    60th: 44.71
    76th: 60.10
    Max: 234.91
    Monitoring Stations: 6
    Copollutant: NR
    Co-pollutant Correlation: N/A
    PM Increment: Interquartile Range
    (27.02 pg/m3)
    Odds Ratio (Lower Cl, Upper Cl):
    Temp >20°C
    PM,0:1.15 (1.10-1.21)*
    PM10+S02:1.23 (1.17, 1.30)*
    PM10+N02:1.03 (0.97, 1.10)
    PMio+C02:1.09 (1.03, 1.15*
    PM10+03:1.10 (1.04, 1.15)*
    Temp <20°C
    PM,0: 0.99 (0.93, 1.05)
    PM10+S02: 0.96 (0.89, 1.03)
    PM10+N02: 0.97 (0.90, 1.04)
    PM,o+C02: 0.96 (0.90, 1.03)
    PM10+03:1.00 (0.94, 1.05)
    *p < 0.05
    Reference: Yang et al. (2007, 0928471  Outcome: Congestive Heart Failure HA
    Period of Study: 1996-2001
    Location: Taipei, Taiwan
    Age Groups: NR
    Study Design: case-crossover
    N:NR
    Statistical Analyses: Poisson
    Covariates: NR
    Dose-response  Investigated? No
    Statistical Package: SAS
    Lags Considered: Lags 0-3
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD):
    Index days:  111.68 (38.32)
    Comparison days: 55.43 (24.66)
    Monitoring Stations: 7
    Copollutant: NR
    Co-pollutant Correlation: N/A
    PM Increment: Index (>125 pg/m ) vs..
    Comparison (<125 pg/m3)
    Relative Risk (Lower Cl, Upper Cl),
                                                                                                              0.915(0.805, 1.041), lag 0
                                                                                                              1.114(0.993, 1.250), lag 1
                                                                                                              0.983(0.873, 1.106), lag 2
                                                                                                              0.974(0.870, 1.090), Iag3
    December 2009
                                    E-99
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Villeneuve et al. (2006,
    0901911
    
    Period of Study: Apr 1992-Mar 2002
    
    Location: Edmonton, Canada
    Outcome (ICD-9): Stroke (430-438),
    including ischemic stroke (434-436),
    hemorrhagic stroke (430,432), and
    transient ischemic attacks (TIA) (435).
    
    Age Groups: 65+ yr
    
    Study Design: Case-crossover
    
    N: 12,422 visits
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature and relative
    humidity
    
    Season: summer (Apr-Sep), winter
    (Oct-Mar)
    
    Dose-response Investigated: No
    
    Statistical Package: SAS (PHREG)
    
    Lags Considered: 0,1, and 3 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Mean (SD):
    All yr:
    24.2(14.8)
    Summer: 25.9 (16.4)
    Winter: 22.6 (12.9)
    Monitoring Stations: 3
    
    Copollutant (correlation):
    Allyr
    S02:r = 0.19
    N02:r = 0.34;
    CO: r = 0.30
    Os-mean: r = 0.07;
    03-max:r = 0.22
    PM25:r = 0.79
    
    Summer
    S02:r = 0.18
    N02:r = 0.57;
    CO: r = 0.38
    Oj-mean: r = 0.20;
    Os-max: r = 0.40
    PM25:r = 0.85
    
    Winter
    S02:r = 0.27
    N02:r = 0.48;
    CO: r = 0.53
    03-mean:r = -0.26;
    03-max: r = -0.09
    PM25:r = 0.70
    PM Increment: pg/m  (IQR)
    Allyr: 16.0
    Summer: 17.5
    Wnter: 16.0
    Adjusted OR Estimate [Cl]: Acute
    ischemic stroke
    Allyr
    Same-day lag: 0.98 [0.94,1.03]
    1-day lag: 1.00 [0.96,1.05]
    3-day lag: 0.99 [.93,1.05]
    summer
    Same-day lag: 0.93 [0.87,1.00]
    1-day lag: 1.01 [0.94,1.08
    3-day lag: 0.96 [0.88,1.04
    Wnter
    Same-day lag: 1.04 [0.97,1.11]
    1-day lag: 1.00 [0.94,1.06];
    3-day lag: 1.05 [0.95,1.15]
    Hemorrhagic stroke
    Allyr
    Same-day lag: 1.01 [0.90,1.12]
    1-day lag: 1.03 [0.93,1.15
    3-day lag: 1.13 [0.98,1.30
    summer
    Same-day lag: 1.02 [0.88,1.20]
    1-day lag: 1.07 [0.91,1.26]
    3-day lag: 1.20 [0.98,1.46]
    Wnter
    Same-day lag: 1.05 [0.90,1.22]
    1-day lag: 1.04 [0.91,1.19]
    3-day lag: 1.11 [0.90,1.37]
    Transient cerebral ischemic attack
    Allyr
    Same-day lag: 0.96 [0.90,1.02]
    1-day lag: 0.99 [0.94,1.05]
    3-day lag: 0.94 [0.87,1.01]
    summer
    Same-day lag: 0.97 [0.89,1.09]
    1-day lag: 0.99 [0.91,1.08]
    3-day lag: 0.94 [0.84,1.04]
    Wnter
    Same-day lag: 0.95 [0.87,1.04]
    1-day lag: 0.99 [0.92,1.07
    3-day lag: 0.93 [0.83,1.05
    Notes: Adjusted ORs are provided for
    an IQR increase in the 3-day mean in
    Fig 1-4 for single and two-pollutant
    models.
    December 2009
                                    E-100
    

    -------
    Reference
    Reference: von Klot et al. (2005,
    0880701
    
    Period of Study: 1992-2001
    Location :
    Augsburg, Germany
    Barcelona, Spain
    Helsinki, Finland
    Rome, Italy
    Stockholm, Sweden
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Wellenius et al. (2005,
    0874831
    Period of Study: Jan 1987-Nov 1999
    Location: Pittsburgh, Pennsylvania
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome (ICD-9): Acute myocardial
    infarction (410
    
    ICD-10: 121-122), angina pectoris (411,
    413
    ICD-10: 120, 124), dysrhythmia (427
    ICD-10: 146.0, 46.9, I47-I49, R00.1,
    R00.8), heart failure (428
    ICD-10: 150)
    
    Age Groups: 35+ yr
    Study Design: Cohort
    N: 22,006 Ml survivors
    
    Statistical Analyses: GAM, Spearman
    correlation
    
    Covariates: Temperature, dew point
    temp, avg barometric pressure, relative
    humidity
    Season: NR
    Dose-response Investigated: No
    Statistical Package: R
    
    Lags Considered: 0-3 days
    
    
    
    
    
    
    
    
    
    
    Outcome (ICD-9): Congestive heart
    failure (428.0-428.1)
    Age Groups: 65+ yr
    Study Design: Case-crossover
    N: 55,019 patients
    Statistical Analyses: Conditional
    logistic regression, Pearson's pain/vise
    correlation
    
    Covariates: Temperature, barometric
    pressure, dew point
    Season: NR
    Dose-response Investigated: No
    Statistical Package: SAS
    Lags Considered: 0-3 days
    Concentrations1
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Mean (6th-96th percentile):
    Augsburg: 44.7 (16.8-81. 4)
    Barcelona: 52.2 (25.3-89.2)
    Helsinki: 25.3 (9.5-57.6)
    Rome: 51.1 (23.3-89.4)
    Stockholm: 14.6 (6.4-30.0)
    Monitoring Stations: NR
    Copollutant (correlation):
    Augsburg
    PNC: r = 0.52
    CO: r = 0.57;
    N02:r = 0.64
    03: r = -0.32
    
    Barcelona
    PNC: r = 0.29
    CO: r = 0.39;
    N02:r = 0.36
    03:r = -0.14
    Helsinki
    PNC: r = 0.46
    CO: r = 0.21;
    N02:r = 0.40
    03: r = 0.02
    
    Rome
    PNC: r = 0.33
    CO: r = 0.31;
    N02:r = 0.48
    03:r = -0.22
    Stockholm
    PNC: r = 0.06
    CO: r = 0.38;
    N02:r = 0.29
    03:r = 0.15
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean 5th-95th percentile):
    31.06 8.89-70.49)
    SD = 20.10
    Monitoring Stations: 17
    Copollutant (correlation):
    CO: r = 0.57
    
    N02:r = 0.64
    03:r = 0.29
    S02:r = 0.51
    
    
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    
    Pooled RR Estimate [Cl]:
    All cardiac admissions: 1.021
    [1.005,1.048]
    Myocardial infarction: 1.026
    [0.995,1.058]
    Angina pectoris: 1.008 [0.986,1.032]
    Notes: Rate ratios for 0-3 day lags are
    provided in graphical form (Fig 1).
    Same-day levels were significantly
    associated with cardiac readmissions.
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    PM Increment: 24 pg/m3 (IQR)
    Percent Increase [Cl]: Single-pollutant:
    3.07 [1.59,4.57]
    Adj. for CO: -1.10 [-3.02,0.86]
    Adj. for N02: 0.52 [-1.46,2.53]
    Adj. for 03: 2.80 [1.29,4.33]
    Adj. for S02: 2. 18 [0.37,4.02]
    
    Percent Increase (with 10 pg/m3
    increment)
    1.27 [0.66, 1.88]
    
    
    
    December 2009
    E-101
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Wellenius et al. (2005,
    0886851
    Period of Study:
    Jan 1986-Nov 1999
    Location:
    Birmingham, Chicago, Cleveland,
    Detroit, Minneapolis, New Haven,
    Pittsburgh, Salt Lake City, Seattle
    Outcome (ICD-NR): Ischemic stroke
    and hemorrhagic stroke
    Age Groups: 65+ yr
    Study Design: Case-crossover (time-
    stratified)
    N: 115,503 hospital admissions
    Statistical Analyses: Conditional
    logistic regression
    Covariates: Temperature and humidity
    Season: NR
    Dose-response Investigated: No
    Statistical Package: SAS (v.9) and R-
    statistical package
    Lags Considered: 0-2 days
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): 32.69 (19.75)
    Monitoring Stations: NR
    (data obtained from the U.S. EPA)
    Copollutant (correlation):
    CO: r = 0.43
    N02:r = 0.53
    S02:r = 0.39
    Other variables: Temp: r = 0.22
    PM Increment: 22.96 pg/rri  (IQR)
    Percent Increase [Cl]: Ischemic (same-
    day lag): 1.03 [0.04,2.04]
    Hemorrhagic: -0.58 [-5.48,4.58]
    Notes: Percent increase in rate for
    ischemic and hemorrhagic stroke are
    provided for each city in graphical form
    (Fig A and B).
    Reference: Wellenius et al.,(2006,
    0887481
    Period of Study:
    Jan 1986-Nov 1999
    Location:
    Birmingham, Chicago, Cleveland,
    Detroit, Minneapolis, New Haven,
    Pittsburgh, Salt Lake City, Seattle
    Outcome (ICD-9): Congestive heart
    failure (428)
    Age Groups: 65+ yr
    Study Design: Case-crossover (time-
    stratified)
    N: 292,918 admissions
    Statistical Analyses: Conditional
    logistic regression
    Covariates: Temperature and
    barometric pressure
    Season: NR
    Dose-response Investigated: No
    Statistical Package: SAS (v.9) and R-
    statistical package
    Lags Considered: 0-3 days
    Pollutant: PM,0
    Averaging Time: 24 h
    Median: Overall: 28.3
    Birmingham: 33.0
    Chicago: 31.5
    Cleveland: 34.5
    Detroit: 29.5
    Minneapolis: 24.0
    New Haven: 22.
    Seattle: 25.8
    Monitoring Stations: NR
    (data obtained from the U.S. EPA)
    Copollutant: NR
    PM Increment: 10 pg/m
    Percent Increase [Cl]: Same-day lag:
    0.72 [0.35,1.10]
    p-value = 0.0002
    Notes: City-specific percent increases
    are graphed in Fig  1 for same-day lag
    showing a significant association in
    Chicago, Detroit, Seattle, and the
    summary values.
    Percent increase in admission rate s
    are provided for lag 0-3 days in Fig 2
    where same-day lag showed a
    significant association.
    Reference: Yang et al. (2004, 0943761
    Period of Study: 1997-2000
    Location: Kaohsiung, Taiwan
    Outcome (ICD-9): Cardiovascular
    diseases (410-429)
    Age Groups: All
    Study Design: Case-crossover
    N: 29,661 admissions
    Statistical Analyses: Conditional
    logistic regression
    Covariates: Temperature and humidity
    Season: NR
    Dose-response Investigated: No
    Statistical Package: SAS
    Lags Considered: Cumulative 0-2
    days
    Pollutant: PM,0
    Averaging Time: 24 h
    Median (min-max): 78.82 (20.50-
    217.33)
    Monitoring Stations: 6
    Copollutant: NR
    PM Increment: 66.33 pg/m3 (IQR)
    OR Estimate [Cl]: Temp >25°C: 1.439
    [1.316,1.573]
    Temp <25°C: 1.568 [1.433,1.715]
    Adj for S02
    Temp >25°C: 1.460 [1.333,1.599]
    Temp <25°C: 1.543 [1.404,1.696]
    Adj for N02
    Temp >25°C: 1.306 [1.154,1.478]
    Temp <25°C: 0.912 [0.809,1.028]
    Adj for CO
    Temp >25°C: 1.260 [1.144,1.388]
    Temp <25°C: 1.259 [1.128,1.406]
    Adj for 03
    Temp >25°C: 1.086 [0.967,1.220]
    Temp <25°C: 1.703 [1.541,1.883]
    December 2009
                                    E-102
    

    -------
               Reference
    Design & Methods
                                                                                  Concentrations1
    Effect Estimates (95% Cl)
    Reference: Yang et al. (2008,1571601   Outcome (ICD-9): Congestive heart
    Period of Study: 1996-2004
                                       Age Groups: All
    Location: Taipei, Taiwan
                                       Study Design: Case-crossover
                                       N: 24,240 CHF hospital admissions
                                       Statistical Analyses: Conditional
                                       logistic regression
                                       Covariates: temperature, humidity
                                       Season: All
                                       Dose-response Investigated: No
                                       Statistical Package: SAS
                                       Lags Considered: Cumulative lag 0-2
                                       days
                                                                          Pollutant: PM,0
                                                                          Averaging Time: 24 h
                                                                          Mean (median, range, IQR):
                                                                          49.47(4471,14.42-234.91,
                                                                          33.08-44.71)
                                                                          Monitoring Stations: 6
                                                                          Copollutant: NR
                                                                   PM Increment: 27.02 pg/rri  (IQR)
                                                                   OR [95% Cl]:
                                                                   Single pollutant models: >20 °C: 1.15
                                                                   [1.10-1.21]
                                                                   <20°C: 0.99 [0.93-1.05]
                                                                   Adjusted  for S02:> 20 °C: 1.23
                                                                   [1.17-1.30]
                                                                   <20°C: 0.96 [0.89-1.03]
                                                                   Adjusted  for N02:> 20 °C: 1.03
                                                                   [0.97-1.10]
                                                                   <20°C: 0.97 [0.90-1.04]
                                                                   Adjusted  for CO: > 20 °C: 1.09
                                                                   [1.03-1.15]
                                                                   <20°C: 0.96 [0.90-1.03]
                                                                   Adjusted  for 03:> 20 °C: 1.10
                                                                   [1.04-1.15]
                                                                   <20°C: 1.00 [0.94-1.05]
    Reference: Zanobetti and Schwartz
    (2002, 0348211
    Period of Study: 1988-1994
    Location:
    Cook county (Chicago), Illinois
    Wayne county (Detroit), Michigan
    Allegheny county (Pittsburgh),
    Pennsylvania
    and King county (Seattle), Washington
    
    
    
    Outcome (ICD-9): Cardiovascular Pollutant: PM10
    disease (390-429) with/without diabetes
    (250) Averaging Time: 24 h
    Age Groups: 65-74 and 75+ yr with Median (25-75th percentile):
    diabetes, 65-74 and 75+ yr without Chicago: 33 (23-46)
    dlabetes Detroit: 32 (2 1-49)
    Study Design: Time series pittsburgh. 3Q (19.4y)
    N: NR Seattle: 27 (18-39)
    Statistical Analyses: GAM, meta- Monjtorjng statjons. NR (ob(ained
    regression from USEPAAerometric Information
    Covariates: Temperature, prior day's Retrieval System)
    temperature, relative humidity, r«n«ii,,*an*. MP
    barometric pressure, day of the week c°P°llutant- NR
    Season: NR
    PM Increment: 10 pg/m3
    Perc
    All 4
    <75
    75+
    <75
    75+
    ent Change [Cl]:
    cities
    w/ diabetes): 1.6 [1.2,2.0]
    w/ diabetes): 2.0 [1.6,2.4]
    w/o diabetes): 0.9 [0.6,1.1]
    w/o diabetes): 1.3 [1.0,1.5]
    ChicPnn
    <75
    75+
    <75
    75+
    Platr
    uetr
    <75
    75+
    <75
    w/ diabetes): 1.9 [1.1,2.7]
    w/ diabetes): 2.0 [1.1,3.0]
    w/o diabetes): 0.7 [0.2,1.2]
    w/o diabetes): 1.2 [0.8,1.7]
    
    w/ diabetes): 1.3 [0.5,2.2]
    w/ diabetes): 2.1 [1.0,3.1]
    w/o diabetes): 1.2 [0.7,1.7]
    75+ (w/o diabetes): 1.2 [0.7,1.6]
    
    Dose-response Investigated: No
    
    
    Pittsburgh
    <75(w/ diabetes): 1.8 [0.9,2.7]
    
    
    
    
    75+
    <75
    w/ diabetes): 0.9 [-0.2,2.0]
    w/o diabetes): 0.6 [0.1, 1.2]
    75+ (w/o diabetes): 1.6 [1.2,2.1]
    Seattle
    <75(w/ diabetes): 1.9 [0.1,3.7]
    
    
    
    
    75+
    <75
    w/ diabetes): 2.7 [0.7,4.8]
    w/o diabetes): 0.8 [0.0,1.6]
    75+ (w/o diabetes): 0.9 [0.2,1.6]
    Notes: Overall percent increases were
    also provided for each city, yielding
    similar results.
    December 2009
                            E-103
    

    -------
               Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Zanobetti and Schwartz
    (2005, 0880691
    
    Period of Study: 1985-1999
    Location:
    21 U.S. cities (Birmingham, Alabama
    Boulder, Colorado
    Canton, Ohio
    Chicago, Illinois
    Cincinnati, Ohio
    Cleveland, Ohio
    Colorado Springs, Colorado
    Detroit, Michigan
    Honolulu, Hawaii
    Houston, Texas
    Minneapolis-St. Paul, Minnesota
    Nashville, Tennessee
    New Haven, Connecticut
    Pittsburgh, Pennsylvania
    Provo-Orem, Utah
    Salt Lake City, Utah
    Seattle, Washington
    Steubenville, Ohio
    Youngstown, Ohio)	
    Outcome (ICD-9): Myocardial infarction
    (410)
    
    Age Groups: >65 yr
    
    Study Design: Case-crossover
    
    N: 302,453 admissions
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature
    
    Season: NR
    
    Dose-response Investigated: Yes
    
    Statistical Package: SAS (PROC
    PHREG)
    
    Lags Considered: 0-2 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Median: Ranged from 15.5-34.1Avg
    across all cities = 27
    PM Increment: 10 pg/m
    
    Percent Increase [Cl]: Ml only: 0.65
    [0.3,1]
                                       Previous COPD admission: 1.3 [-
                                       0128]
    Monitoring Stations: 1+ (data obtained
    from USEPAsAerometric Information    Secondary pneumonia diagnosis: 1.4 [-
    Retrieval System)
    Copollutant: NR
    0.8,3.6]
    
    Notes: Fig 1 presents percent change
    in Ml per lag day, showing same-day
    lag to be significant. Fig 2 shows
    percent change with/without other co-
    morbidities.
    1AII units expressed in ug/m3 unless otherwise specified.
    Table E-6.     Short-term exposure-cardiovascular-ED/HA - PMi0.2.6-
    Reference
    Reference: Halonen et al. (2009,
    1803791
    Period of Study: 1998-2004
    Location: Helsinki, Finland
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Cardiovascular
    Hospitalizations & Mortality (ICD 10:
    100-99)
    
    Age Groups: 65+ yr
    Study Design: Time series
    N:NR
    Statistical Analyses: Poisson, GAM
    Covariates: Temperature, humidity,
    influenza epidemics, high pollen
    episodes, holidays
    Dose-response Investigated? No
    Statistical Package: R
    Lags Considered: lags 0-3 days; 5-day
    (0-4) mean
    
    
    
    
    
    
    
    
    
    Concentrations1
    Pollutant: PM10.2.5
    Averaging Time: Daily
    
    Mean (SD): NR
    Min:0.0
    26th percentile: 4.9
    60th percentile: 7.5
    76th percentile: 12.1
    Max: 101. 4
    Monitoring Stations: NR
    Copollutant:
    PMO.03, PM0.03-0.1,PM<0.1,
    PM<0. 10.29, PM25, CO, N02
    Co-pollutant Correlation
    PMO.03: 0.14
    
    PMO.03-0. 1:0.28
    PM<0. 1:0.24
    PM<0.10.29:0.20
    PM25: 0.25
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: Interquartile Range
    Percent Change (Lower Cl, Upper
    Cl):
    All Cardiovascular Morality
    Lag 0: -0.01 (-1.52, 1.53)
    Lag 1: -0.26 (-1.69, 1.18)
    Lag 2: -0.61 (-2.03, 0.83)
    Lag 3: -0.57 (-1.98, 0.85)
    5-day mean: -0.70 (-2.56, 1.20)
    Coronary Heart Disease HA
    Lag 0:1. 12 (-0.28, 2.55)
    Lag 1: -0.38 (-1.68, 0.94)
    Lag 2: 0.01 (-1.33, 1.37)
    Lag 3: -0.53 (-1.82, 0.78)
    5-day mean: 0.23 (-0.29, 0.75)
    Stroke HA
    Lag 0: -1.33 (-3.26, 0.63)
    Lag 1: -1.90 (-3.82, 0.07) J
    Lag 2: -1.09 (-3.04, 0.89)
    Lag 3: -0.51 (-2.40, 1.43)
    5-day mean: -2.21 (-4.75, 0.39)
    Arrhythmia HA
    Lag 0:0.57 (-1.33, 2.49)
    Lag 1: -0.65 (-2.55, 1.29)
    Lag 2: 0.02 (-1.93, 2.00)
    Lag 3: -1.34 (-3.26, 0.62)
    5-day mean: -1.11 (-3.68, 1.53)
    *p < 0.05, Jp< 0.10
    December 2009
                                   E-104
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Host et al. (2008,
    155852)(Host et al, 2008,1558521
    
    Period of Study: 2000-2003
    
    Location: Six French cities: Le Havre,
    Lille, Marseille, Paris, Rouen, and
    Toulouse
    Outcome (ICD-10): Daily
    hospitalizations for all cardiovascular
    (IOO-I99), cardiac (IOO-I52), and
    ischemic heart diseases (I20-I25).
    
    Age Groups: For cardiovascular
    diseases: All ages, and restricted to 2
    65 yr
    
    Study Design: Time series
    
    N: NR (Total population of cities:
    approximately 10 million)
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Seasons, days of the
    week, holidays, influenza epidemics,
    pollen counts, temperature, and
    temporal trends
    
    Dose-response Investigated: No
    
    Statistical Package:  MGCV package in
    R software (R 2.1.1)
    
    Lags  Considered: Avg of 0-1 days
    Pollutant: PM10.2.5
    
    Averaging Time: 24 h
    
    Mean ug/m3 (6th -96th percentile):
    Le Havre: 7.3 (2.5-14.0)
    
    Lille: 7.9 (2.2-137)
    
    Marseille: 11.0(4.5-21.0)
    
    Paris: 8.3 (3.2-15.9)
    
    Rouen: 7.0 (3.0-12.5)
    
    Toulouse: 7.7 (3.0-15.0)
    
    Monitoring Stations:
    13 total:
    1 in Toulouse
    
    4 in Paris
    
    2 each in other cities
    
    Copollutant (correlation): PM25:
    Overall: r>0.6
    
    Ranged between r = 0.28 and r = 0.73
    across the six cities.
    PM Increment: 10 pg/m  , and an
    18.8 pg/m3 increase (corresponding to
    an increase in pollutant levels between
    the lowest of the 5th percentiles and the
    highest of the 95th percentiles of the
    cities' distributions)
    
    ERR (excess relative risk) Estimate [Cl]:
    For all cardiovascular diseases
    (10 pg/m increase): All ages: 0.5% [-
    1.2,2.3]
    
    > 65 yr: 1.0% [-1.0, 3.0]
    
    For all cardiovascular diseases
    (18 pg/m3 increase): All ages: 1.0% [-
    2.3, 4.3]
    
    > 65 yr: 1.9% [-2.0, 5.9]
    
    For cardiac diseases (10  pg/m3
    increase): All ages: 0.1%  [-1.9, 2.1]
    
    > 65 yr: 1.6% [-0.8, 4.1]
    
    For cardiac diseases (18.8 pg/m3
    increase): All ages: 0.1%  [-3.6, 4.0]
    
    > 65 yr: 3.1% [-1.5, 7.9]
    
    For ischemic heart diseases (10 pg/m3
    increase): All ages: 2.8%  [-0.8, 6.6]
    
    > 65 yr: 6.4% [1.6,11.4]
    
    For ischemic heart diseases (18 pg/m3
    increase): All ages: 5.4%  [-1.5,12.8]
    
    > 65 yr: 12.4 [3.1, 22.6]
    Reference: Metzger et al. (2004,
    0442221
    
    Period of Study: Aug 1998-Aug 2000
    
    Location: Atlanta Metropolitan area
    (Georgia)
    Outcome (ICD-9): Emergency visits for
    ischemic heart disease (410-414),
    cardiac dysrhythmias (427), cardiac
    arrest (427.5), congestive heart failure
    (428), peripheral vascular and
    cerebrovascular disease (433-437, 440,
    443-444, 451-453), atherosclerosis
    (440), and stroke (436).
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 4,407,535 emergency department
    visits between 1993-2000 (data not
    reported for 1998-2000)
    
    Statistical Analyses: Poisson
    generalized linear modeling
    
    Covariates: Day of the wk, hospital
    entry and exit indicator variables,
    federally observed holidays, temporal
    trends, temperature,  dew point
    temperature
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: SAS
    
    Lags Considered: 3-day ma; lags 0 -7
    Pollutant: PM,0 -2.5
    
    Averaging Time: 24 h
    
    Median ug/m3 (10% - 90% range):
    9.1 (4.4, 16.2)
    
    Monitoring Stations: 1
    
    Copollutant (correlation):
    PM10:r = 0.59
    03:r = 0.35
    N02:r = 0.46
    CO: r = 0.32
    S02:r = 0.21
    PM25:r = 0.43
    UFP:r = 0.13
    PM25water
    soluble metals: r = 0.47
    PM25sulfates:r = 0.26
    PM25 acidity: r = 0.23
    PM25OC:r = 0.51
    PM25EC:r = 0.48
    PM25 oxygenated hydrocarbon: r = 0.31
    Other variables: Temperature: r = 0.20
    Dew point: r = 0.00
    PM Increment: 5 pg/m  (approximately
    1SD)
    
    RR [95% Cl]: For 3 day ma: All CVD:
    1.012 [0.985, 1.040]
    
    Dysrhythmia: 1.021 [0.974,1.070]
    
    Congestive heart failure: 1.020
    [0.964-1.079]
    
    Ischemic heart disease: 0.994
    [0.946-1.045]
    
    Peripheral vascular and
    cerebrovascular disease: 1.022
    [0.972-1.074]]
    
    Results for Lags 0-7 expressed in
    figures (see notes).
    
    Notes: Fig 1: RR (95% Cl) for single-
    day lag models for the association of
    ER visits for CVD with daily ambient
    PM,0-2.5.
    
    Summary of Fig 1 results: Positive
    association at Lag 0.
    December 2009
                                     E-105
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Peng et al. (2008,1568501
    
    Period of Study: Jan 1999-Dec 2005
    
    Location: 108 U.S. counties in the
    following states: Alabama, Arizona,
    California, Colorado, Connecticut,
    District of Columbia, Florida, Georgia,
    Idaho, Illinois, Indiana, Kentucky,
    Louisiana, Maine, Maryland,
    Massachusetts, Michigan, Minnesota,
    Missouri, Nevada, New Hampshire,
    New Jersey, New Mexico, New York,
    North Carolina, Ohio, Oklahoma,
    Oregon, Pennsylvania, Rhode Island,
    South Carolina, Tennessee, Texas,
    Utah, Virginia, Washington,  West
    Virginia, Wisconsin
    Outcome (ICD-9): Emergency
    hospitalizations for: Cardiovascular
    disease, including heart failure (428),
    heart rhythm disturbances (426-427),
    cerebrovascular events (430-438),
    ischemic heart disease (410-414, 429),
    and peripheral vascular disease
    (440-448).
    
    Age Groups: 65 + yr, 65-74, 75+
    
    Study Design: Time series
    
    N: approximately 12 million Medicare
    enrollees (3.7 million CVD and 1.4
    million RD admissions)
    
    Statistical Analyses: Two-stage
    Bayesian hierarchical models:
    Overdispersed Poisson models for
    county-specific data.  Bayesian
    hierarchical models to obtain national
    avg estimate
    
    Covariates: Day of the wk, age-specific
    intercept, temperature, dew point
    temperature, calendar time, indicator for
    age of 75 yr or older.  Some models
    were adjusted for PM25.
    
    Dose-response Investigated: No
    
    Statistical Package: R version 2.6.2
    
    Lags Considered: 0-2 days
    Pollutant: PM10.2.5
    
    Averaging Time: 24 h
    
    Mean ug/m3 (IQR):
    All counties assessed: 9.8 (6.9-15.0)
    
    Counties in Eastern U.S.: 9.1 (6.6-13.1)
    
    Counties in Western U.S.: 15.4
    (10.3-21.8)
    
    Monitoring Stations: At least 1  pair of
    co-located monitors (physically located
    in the same place) for PM10 and  PM25
    per county
    
    Copollutant (correlation):
    PM25:r = 0.12
    
    PM10:r = 0.75
    
    Other variables: Median within-county
    correlations between monitors: r = 0.60
    PM Increment: 10 pg/m
    
    Percentage change [95% Cl]: CVD: Lag
    0 (unadjusted for PM25): 0.36 [0.05,
    0.68]
    
    Lag 0 (adjusted for PM25): 0.25 [-0.11,
    0.60]
    
    Notes: Effect estimates for PMi0.25 (0-2
    day lags) are showing in Fig 2-5.
    Fig 2: Percentage change in emergency
    hospital admissions for CVD per
    10 pg/m3 increase in PM (single
    pollutant model and model adjusted for
    PM2 5 concentration)
    
    Fig 4: Percentage change in emergency
    hospital admissions rate for CVD and
    RD per a 10 pg/m  increase in PMi0.2.5
    (0-2 day lags, Eastern vs.. Western
    USA)
    
    Fig 5: County-specific log relative risks
    of emergency hospital admissions for
    CVD per 10 pg/m increase in PMi0.25
    at Lag 0 (unadjusted for  PM25 and
    plotted vs.. percentage of urbanicity)
    
    No significant associations between
    PMio.25and cause-specific
    cardiovascular disease.
    Reference: Tolbert et al. (2007,
    0903161
    
    Period of Study: Aug 1998-Dec 2004
    
    Location: Atlanta Metropolitan area,
    Georgia
    Outcome (ICD-9): Combined CVD
    group, including: Ischemic heart
    disease (410-414), cardiac
    dysrhythmias (427), congestive heart
    failure (428), and peripheral vascular
    and cardiovascular disease (433-437,
    440, 443-445, and 451-453)
    
    Age Groups: All
    
    Study Design: Time series
    
    N: NR for 1998-2004. For 1993-2004:
    10,234,490 ER visits (283,360 visits).
    
    Statistical Analyses: Poisson
    generalized linear models
    
    Covariates: Long-term temporal trends,
    temperature, dew point, days of week,
    federal holidays, hospital entry and exit
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: SAS version 9.1
    
    Lags Considered: 3-day ma (lag 0-2)
    Pollutant: PMi0.25
    
    Averaging Time: 24 h
    
    Mean (ug/m3) (median IQR, range,
    10th-90th percentiles):
    9.0(8.2
    
    5.6-11.5
    
    0.5-50.3
    
    3.6-15.1)
    
    Monitoring Stations: 1
    Copollutant (correlation):
    PMi0:r = 0.67
    03:r = 0.36
    N02:r = 0.48
    CO:r = 0.38S02:r = 0.16
    PM25:r = 0.47
    PM25S04:r = 0.32
    PM25EC:r = 0.49
    PM25OC:r = 0.49
    PM25TC:r = 0.51
    PM2 5 water-sol metals: r = 0.50
    OHC:r = 0.41
    PM Increment: 5.89 pg/m3 (IQR)
    
    Risk ratio [95% Cl]: CVD: 1.004
    (0.990-1.019)
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                                     E-106
    

    -------
    Table E-7.      Short-term exposure - cardiovascular: ED/HA PM2.6 (including PM components/sources)
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Andersen et al. (2008,
    1896511
    Period of Study: May 2001-Dec 2004
    
    Location: Copenhagen, Denmark
    Outcome (ICD-10): CVD, including
    angina pectoris (I20), myocardial
    infarction (121-22), other acute ischemic
    heart diseases (I24), chronic ischaemic
    heart disease (I25), pulmonary
    embolism (I26), cardiac arrest (I46),
    cardiac arrhythmias (148-48), and heart
    failure (ISO). RD,  including chronic
    bronchitis (J41-42), emphysema (J43),
    other chronic obstructive pulmonary
    disease (J44), asthma  (J45), and status
    asthmaticus (J46). Pediatric hospital
    admissions for asthma (J45) and status
    asthmaticus (J46).
    
    Age Groups: > 65 yr (CVD and RD),
    5-18 yr (asthma)
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Poisson GAM
    
    Covariates: Temperature, dew-point
    temperature, long-term trend,
    seasonality, influenza, day of the week,
    public holidays, school holidays (only
    for 5-18 yr olds),  pollen (only for
    pediatric asthma  outcome)
    
    Season: NR
    
    Dose-response  Investigated: No
    
    Statistical Package: R statistical
    software (gam procedure, mgcv
    package)
    
    Lags Considered: Lag 0-5 days, 4-day
    pollutant avg (lag 0-3) for CVD, 5-day
    avg (lag 0-4) for RD, and a 6-day avg
    (lag 0-5) for asthma.
    Pollutant: PM25
    
    Averaging Time: 24 h
    Mean ugm3 (SD): 10(5)
    Median: 9
    IQR:7-12
    99th percentile): 28
    Monitoring Stations: 1
    
    Copollutant (correlation):
    NCtot:r = 0.40
    NC100:r = 0.29
    NCa12:r = 0.07
    Nca23:r = -0.25
    NCa57:r = 0.51
    NCa212:r = 0.82
    PM10:r = 0.80
    CO: r = 0.46
    N02:r = 0.42
    N0x:r = 0.40
     curbside:r = 0.28
    03:r = -0.20
    Other variables:
    Temperature: r = -0.01
    Relative humidity: r = 0.21
    PM Increment: 5 pg/m  (IQR)
    
    Relative risk (RR) Estimate [Cl]: CVD
    hospital admissions (4-day avg, lag 0 -
    3), age 65+: One-pollutant model: 1.03
    [1.01-1.06]
    
    Adj for NCtot: 1.03 [1.01-1.06]
    
    RD hospital admissions (5-day avg, lag
    0-4), age 65+:
    
    One-pollutant model: 1.00 [0.95-1.00]
    
    Adj for NCtot: 1.00 [0.95-1.06]
    
    Asthma hospital admissions (6-day avg
    lag 0-5), age 5-18:
    
    One-pollutant model: 1.15 [1.00-1.32]
    
    Adj for NCtot: 1.13 [0.98-1.32]
    
    Estimates for individual day lags
    reported only in Fig form (see notes):
    
    Notes: Fig 2: Relative risks and 95%
    confidence intervals per IQR  in single
    day concentration (0-5 day lag).
    Summary: CVD: Marginally significant
    association at Lag 0. RD: No
    statistically or marginally significant
    associations. Positive associations at
    Lag 4-5.Asthma: Wide confidence
    intervals make interpretation difficult.
    Positive associations at Lag 1, 2, 3.
    December 2009
                                   E-107
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ballester et al. (2006,
    0887461
    Period of Study: 1995-1999
    
    Location: 6 Spanish cities: Barcelona,
    Bilbao, Pamplona, Valencia, Vigo,
    Zaragoza
    Outcome (ICD-9): The number of daily
    emergency admissions with primary
    diagnosis for all cardiovascular disease
    (390-459) and heart diseases (410-414,
    427, 428)
    
    Age Groups: All ages
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Poisson GAMs
    
    Covariates: Daily temperature,
    barometric pressure, and relative
    humidity
    
    Daily influenza incidence, day of the
    week, holidays, unusual events (ex.
    medical strikes), seasonal variation,
    trend of the series
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: S-Plus GAM
    function
    
    Lags Considered: 0-3 days, 0- to
    1-dayavg
    Pollutant: Black smoke (BS)
    
    Averaging Time: 24 h
    
    Mean ug/m3 (10-90th percentile):
    Overall mean NR.
    
    City specific means
    
    Barcelona: 35.0 (19.4, 53.0)
    
    Bilbao: 18.5 (8.8, 31.0)
    
    Pamplona: 7.4  (2.3,13.0)
    
    Valencia: 40.3 (20.3, 66.4)
    
    Vigo: 79.4 (43.9, 122.3)
    
    Zaragoza: 40.4 (23.8, 61.3)
    
    Monitoring Stations: NR
    (at least 3 stations per city)
    
    Copollutant (correlation): Summary of
    the correlation coefficients between
    each pair of pollutants within cities:
    PM,0:r = 0.48
    TSP:fromr = 0.16tor = 0.69
    (median r = 0.43)
    N02: from r = 0.23tor = 0.69
    (median r = 0.48)
    S02: from r = 0.09tor = 0.59
    (median r = 0.24)
    CO: from r = 0.62 to r = 0.69
    (median r = 0.69)
    03: from r = -0.43 to r = -0.06
    (median r =-0.16)	
    PM Increment: 10 pg/m
    
    Relative risk [Cl]: Relative risks are
    expressed only in the form of figures
    (see notes).
    
    Percentage change in risk [Cl]: All
    cardiovascular diseases (avg of lags 0 -
    1)0.24% [-0.18, 0.67]
    
    Heart disease (avg of lags 0 -1) 0.71%
    [0.13,1.29]
    
    Notes:  Relative risks for the single
    pollutant models are expressed in Fig 2.
    Fig 2: Time sequence of the combined
    association between BS and hospital
    admissions for all CVD (A) and heart
    disease (B). Summary: Significant,
    positive association of TSP with both
    overall  CVD and heart disease
    hospitalizations at Lag 0.
    
    Relative risks for 2 pollutant models are
    expressed in Fig 3: Combined
    estimates of the association between
    hospital admissions for heart diseases
    and air pollutants (avg of lags 0-1
    
    Adjusted for CO, N02, 03, or S02).
    Summary: Significant, positive
    association remains after adjusting for
    N02, 03, and S02. Association remains
    positive but becomes marginally
    significant after adjusting for CO.
    Reference: Ballester et al. (2006,
    0887461
    Period of Study: 1993-1999
    
    Location: 7 Spanish cities: Barcelona,
    Bilbao, Cartagena, Castellon, Gijon,
    Oviedo, Valencia
    Outcome (ICD-9): The number of daily   Pollutant: TSP
    emergency admissions with primary
    diagnosis for all cardiovascular disease   Averaging Time: 24 h
    (390-459) and heart diseases (410-414,
    427, 428)
    Mean ug/m3 (10-90th percentile):
    Overall mean NR.
    Age Groups: All ages
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Poisson GAMs
    
    Covariates: Daily temperature,
    barometric pressure, and relative
    humidity
    
    Daily influenza incidence, day of the
    week, holidays, unusual events (ex.
    medical strikes), seasonal variation,
    trend of the series
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: S-Plus GAM
    function
    
    Lags Considered: 0-3 days, 0- to
    1-dayavg
    City specific means
    Barcelona: 51.8 (29.4, 78.8)
    Bilbao: 58.3 (30.3, 92.3)
    Cartagena:  54.9 (32.5, 79.9)
    Castellon: 60.4 (32.0, 92.1)
    Gijon: 77.4 (47.4, 118.3)
    Oviedo: 76.0 (48.3,111.8)
    Valencia: 61.0(44.1, 80.7)
    Monitoring Stations: NR (at least
    three stations per city)
    Copollutant (correlation): Summary of
    the correlation coefficients between
    each pair of pollutants within cities:
    BS: from  r = 0.16tor = 0.69
    (median r = 0.43)
    PM,0:NA
    N02: from r =-0.13tor = 0.65
    (median r = 0.48)
    S02: from r = 0.06tor = 0.69
    (median r = 0.31)
    CO: from r = 0.06 to r = 0.59
    (median r = 0.47)
    03: from r =-0.27 tor = 0.07
    (median r =-0.03)
    PM Increment: 10 pg/m
    
    Relative risk [Cl]: Relative risks are
    expressed only in the form of figures
    (see notes).
    
    Percentage change in risk [Cl]: All
    cardiovascular diseases: 0.07% [-0.23,
    0.36]
    
    Heart disease 0.45% [0.04, 0.86]
    
    Notes: Relative risks for the single
    pollutant models are expressed in Fig 2.
    
    Fig 2: Time sequence of the combined
    association between TSP and hospital
    admissions for all CVD (A) and heart
    disease (B).
    
    Summary of results: Positive, marginally
    significant association of TSP with
    overall  CVD at Lag 0. Positive,
    statistically significant relation between
    TSP and heart disease hospitalizations
    at Lag 0.
    
    Relative risks for 2 pollutant models are
    expressed in Fig 3:
    
    Fig 3: Combined estimates  of the
    association between hospital
    admissions for heart diseases and air
    pollutants (avg of lags 0-1 adjusted for
    CO, N02, 03, or S02).
    
    Summary of results: Small positive
    significant or marginally significant
    associations between TSP and general
    CVD and heart disease hospitalizations
    remain constant after adjustment for
    CO, N02, 03, or S02.
    December 2009
                                     E-108
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Bell et al. (2008, 0912681
    
    Period of Study: 1995-2002
    
    Location: Taipei, Taiwan
    Outcome (ICD-9): Hospital admissions
    for ischemic heart disease (410, 411,
    414), cerebrovascular disease
    (430-437), asthma (493), and
    pneumonia (486).
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 6,909 hospital admissions for
    ischaemic heart diseases, 11,466 for
    cerebrovascular disease, 19,966 for
    pneumonia, and 10,231 for asthma
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Day of the week, time,
    apparent temperature,  long-term trends,
    seasonality
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: NR
    
    Lags Considered:  lags 0-3 days, mean
    of lags 0-3
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean ug/m3 (range IQR):
    31.6(0.50-355.020.2)
    
    Monitoring Stations: 2
    
    Copollutant (correlation): NR
    PM Increment: 20 pg/m  (near IQR)
    
    Percentage increase estimate [95% Cl]:
    Ischemic heart disease: LO: 3.48 (-0.39,
    7.51)
    L1: 3.55 (-0.30, 7.56)
    L2: 3.32 (-0.50, 7.29)
    L3: 2.80 (-1.04, 6.79)
    LOS: 8.38 (2.28, 14.84)
    
    Cerebrovascular disease: LO: -2.22 (-
    50.2, 0.67)
    L1:-1.30 (-4.08, 1.55)
    L2: 0.24 (-2.49, 3.040
    L3:1.21 (-1.41,3.90)
    LOS:-1.45 (-5.58, 2.87)
    
    Asthma: LO: 0.46 (-2.41, 3.42)
    L1:-1.36 (-4.33, 1.71)
    L2:-0.83 (-3.67, 2.10)
    L3:-0.78 (-3.63, 2.16)
    LOS:-1.75 (-6.21, 2.92)
    
    Pneumonia: LO: 0.06 (-2.74, 2.94)
    L1: 0.34 (-2.446, 3.20)
    L2: -0.59 (-3.38, 2.29)
    L3:-0.44 (-3.22, 2.41)
    L03: -0.61 (-4.87, 3.85)	
    Reference: Bell et al. (2008, 0912681
    
    Period of Study: 1999-2005
    
    Location: 202 U.S. counties
    Outcome (ICD-9): Heart failure (428),
    heart rhythm disturbances (426-427),
    cerebrovascular events (430-438),
    ischemic heart disease (410-414, 429),
    peripheral vascular disease (440-449),
    COPD (490-492), respiratory tract
    infections (464 - 466, 480 - 487)
    
    Age Groups: 65+
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Two-stage
    Bayesian hierarchical model to find
    national avg
    
    First stage: Poisson regression (county-
    specific)
    
    Covariates: Day of the week,
    temperature, dew point temperature,
    temporal trends, indicator for persons
    75+ yr, population size
    
    Season: All, Jun-Aug (Summer),
    Sep-Nov (Fall), Dec-Feb (Winter),
    Mar-May (Spring)
    
    Dose-response Investigated: No
    
    Statistical Package: NR
    
    Lags Considered: 0- to 2-day lags
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (ug/m3): Descriptive information
    presented in Fig S2 (boxplots):
    
    IQR: 8.7 pg/m3
    
    Monitoring Stations: NR
    
    Copollutant (correlation): NR
    PM Increment: 10 pg/m
    
    Percent increase [96% PI]:
    
    Cardiovascular admissions:
    Lag 0 (all seasons): 0.80 [0.59-1.01]
    Lag 0 (winter, national): 1.49 [1.09-1.8
    Lag 0 (winter, northeast): 2.01
    [1.39-2.63]
    Lag 0 (winter, southeast): 1.06
    [-0.07-2.21]
    Lag 0 (winter, northwest): 0.85
    [-4.11-6.07]
    Lag 0 (winter, southwest): 0.76
    [-0.25-1.79]
    Lag 0 (spring, national): 0.91
    [0.47-1.35]
    Lag 0 (spring, northeast)
    0.95 [0.32-1.58]
    Lag 0 (spring, southeast): 0.75
    [-0.26-1.78]
    Lag 0 (spring, northwest): -0.07
    [-12.40-13.98]
    Lag 0 (spring, southwest):  1.78
    [-0.87-4.51]
    Lag 0 (summer, national): 0.18
    [-0.23-0.58]
    Lag 0 (summer, northeast): 0.55
    [0.08-1.02]
    Lag 0 (summer, southeast): -0.67
    [-1.60-0.26]
    Lag 0 (summer, northwest): -1.55
    [-15.22-14.31]
    Lag 0 (summer, southwest): -1.20
    [-4.90-2.65]
                                                                                                                  LagO
                                                                                                                  LagO
                                                                                    fall, national): 0.68 [0.29-1.07]
                                                                                    fall, northeast): 1.03 [0.48-1.58]
                                                                                                                  Lag 0 (fall, southeast): 0.17 [-0.72-1.07]
                                                                                                                  Lag 0 (fall, northwest): -0.67
                                                                                                                  [-6.96-6.05]
                                                                                                                  Lag 0 (fall, southwest): 0.30 [-0.98-1.59]
                                                                                                                  Lag1
                                                                                                                  Lag1
                                                                                    all seasons): 0.07 [-0.12-0.26]
                                                                                    winter): 0.56 [0.16-0.96]
                                                                                                                  Lag1 (spring):-0.10 [-0.58-0.39]
                                                                                                                  Lag1
                                                                                                                  Lag1
                                                                                    summer):-0.16 [-0.54-0.22]
                                                                                    fall): 0.04 [-0.28-0.35]
                                                                                                                  Lag2 (all seasons): [0.06 [-0.12-0.23]
                                                                                                                  Lag 2 winter): 0.27 [-0.12-0.65]
                                                                                                                  Lag 2 (spring): 0.19 [-0.23-0.60]
    December 2009
                                     E-109
    

    -------
                   Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                                      Lag 2 (summer): -0.12 [-0.50-0.26]
                                                                                                                      Lag 2 (fall): 0.02 [-0.30-0.34]
                                                                                                                      Respiratory admissions: Lag 0 (all
                                                                                                                      seasons): 0.22 [-0.12-0.56]
                                                                                                                      LagO
                                                                                                                      LagO
                                                                              winter, national): 1.05 [0.29-1.82]
                                                                              winter, northeast): 1.76
                                                                        [0.60-2.93]
                                                                        Lag 0 (winter, southeast): 0.59
                                                                        [-1.35-2.58]
                                                                        Lag 0 (winter, northwest): -0.07
                                                                        [-6.74-7.08]
                                                                        Lag 0 (winter, southwest): 0.03
                                                                        [-1.25-1.34]
                                                                        Lag 0 (spring, national): 0.31
                                                                        [-0.47-1.11]
                                                                        Lag 0 (spring, northeast): 0.34
                                                                        [-0.66-1.34]
                                                                        Lag 0 (spring, southeast): -0.06
                                                                        [-1.77-1.68]
                                                                        Lag 0 (spring, northwest): -8.52
                                                                        [-25.62-12.51]
                                                                        Lag 0 (spring, southwest): 1.87
                                                                        [-2.00-5.90]
                                                                        Lag 0 (summer, national): -0.62
                                                                        [-1.33-0.09]
                                                                        Lag 0 (summer, northeast): -0.8
                                                                        [-1.65-0.07]
                                                                        Lag 0 (summer, southeast): -0.15
                                                                        [-1.88-1.61]
                                                                        Lag 0 (summer, northwest): 0.25
                                                                        [-21.46-27.96]
                                                                        Lag 0 (summer, southwest): 0.64
                                                                        [-5.38-7.04]
                                                                        Lag 0 (fall, national): 0.02 [-0.63-0.67]
                                                                                                                      LagO
                                                                                                                      LagO
                                                                              fall, northeast): -0.01 [-0.87-0.85]
                                                                              fall, southeast): -0.58
                                                                                                                      [-2.06-0.91]
                                                                                                                      LagO (fall, northwest):-1.38
                                                                                                                      [-11.84-10.32]
                                                                                                                      Lag 0 (fall, southwest): 1.77 [-0.73-4.33]
                                                                                                                      Lag1
                                                                                                                      Lag1
                                                                              all seasons): 0.05 [-0.29-0.39]
                                                                              winter): 0.50 [-0.27-1.27]
                                                                                                                      Lag1 (spring):-0.24 [-1.01-0.53]
                                                                                                                      Lag1
                                                                                                                      Lag1
                                                                              summer): 0.28 [-0.39-0.95]
                                                                              fall): 0.15 [-0.49-0.79
                                                                                                                      Lag 2 (all seasons): 0.41 [0.09-0.74]
                                                                                                                      Lag 2
                                                                                                                      Lag 2
                                                                              winter, national): 0.72 [0.01-1.43]
                                                                              winter, northeast): 0.79
                                                                        [-0:21-1.80]
                                                                        Lag 2 (winter, southeast): 0.4 [-1.45,
                                                                        2.27]
                                                                        Lag 2 (winter, northwest): -0.06
                                                                        [-6.52-6.85]
                                                                        Lag 2 (winter, southwest): 1.2
                                                                        [-0.10-2.52]
                                                                        Lag 2 (spring, national): 0.35
                                                                        [-0.29-0.99]
                                                                        Lag 2 (spring, northeast): 0.04
                                                                        [-0.88-0.97]
                                                                        Lag 2 (spring, southeast): 0.75
                                                                        [-0.82-2.34]
                                                                        Lag 2 (spring, northwest): 2.29
                                                                        [-14.26-22.03]
                                                                        Lag 2 (spring, southwest): 1.05
                                                                        [-2.18-4.39]
                                                                        Lag 2 (summer, national): 0.57
                                                                        [-0.07-1.23]
                                                                        Lag 2 (summer, northeast): 0.77
                                                                         -0.01-1.56]
                                                                         Lag 2 (summer, southeast): -0.52
                                                                        [-2.07-1.06]
                                                                        Lag 2 (summer, northwest): 0.74
                                                                        [-18.73-24.86]
                                                                        Lag 2 (summer, southwest): 2.41
                                                                        [-2.61-7.69]
                                                                        Lag 2 (fall, national): 0.39 [-0.22-1.01]
                                                                        Lag 2 (fall, northeast): 0.12 [-0.82-1.07]
                                                                        Lag 2 (fall, southeast): 0.14 [-1.29-1.59]
    December 2009
                               E-110
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                 Lag 2 (fall, northwest): -0.74
                                                                                                                 [-10.08-9.58]
                                                                                                                 Lag 2 (fall, southwest): 0.97[-1.36-3.36]
    Reference: Bell et al. (2009,1910071
    
    Period of Study: 1999-2005
    
    Location: 168 U.S. Counties
    Outcome: CVD hospital admissions
    
    Study Design: Retrospective Cohort
    
    Covariates: Socio-economic
    conditions, long term temperature
    
    Statistical Analysis: Bayesian
    hierarchical model
    
    Age Groups: 2 65 yr
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD) Unit: NR
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 20% of the population
    acquiring air conditioning
    
    Percent Change (96% Cl) in
    community-specific PM health effect
    estimates for CVD hospital
    admissions
    Any AC, including window units
    Yearly health effect: -4.3 (-72.7 to 4.2)
    Summer health effect: -148 (-327 to
    31.1)
    Winter health effect: -80.0 (-182 to 22.0)
    
    Central AC
    Yearly health effect: -42.5(-63.4-21.6)
    Summer health effect: -79.5 (-143 to
    15.7)
    Winter health effect: -41.9 (-124 to 40.0)
    Reference: Bell et al. (2009,1919971
    
    Period of Study: 1999-2005
    
    Location: U.S.
    Outcome: Cardiovascular HA
    
    Age Groups: 65+
    
    Study Design: time series
    
    N:NR
    
    Statistical Analyses: Bayesian
    Hierarchical Regression
    
    Covariates: time trend, day of week,
    seasonality, dew point, temperature
    
    Statistical Package: NR
    
    Lags Considered: 0-2
    Pollutant: PM25
    
    Averaging Time: Daily
    Mean:
    EC: 0.715
    Ni: 0.002
    V: 0.003
    Min:
    EC: 0.309
    Ni: 0.003
    V: 0.001
    Max:
    EC: 1.73
    Ni: 0.021
    V: 0.010
    Interquartile Range:
    EC: 0.245
    Ni: 0.001
    V: 0.001
    Interquartile Range of Percents:
    EC: 1.7
    Ni:0.01
    V: 0.01
    Monitoring Stations: NR
    
    Copollutant: Al, NH4+, As, Ca, Cl, Cu,
    EC, CMC, Fe, Pb, Mg. Ni,  N03-, K, Si,
    Na+, S04=, Ti, V, Zn
    
    Co-pollutant Correlation:
    Ni, V:  0.48
    V, EC: 0.33
    Ni, EC: 0.30
    Note: Pollutant concentrations available
    for all  fractions of PM2 5
    PM Increment: Interquartile Range in
    the fraction of PM2 5
    
    Percent Increase in PM Health Effect
    (Lower Cl, Upper Cl), lag
    EC: 25.8 (4.4, 47.2),  lag 0
    EC+Ni: 14.0 (-7.6, 35.5), lag 0
    EC+ V: 14.9 (-7.8, 37.6), lag 0
    EC+ V, HS education: 15.0 (3.3, 26.8),
    lagO
    EC+ V, median income: 15.8 (4.1, 27.5),
    lagO
    EC+ V, racial composition: 14.2 (2.8,
    25.6), lag 0
    EC+ V, percent living in urban area:
    14.7(3.1,26.3),  lag 0
    EC+ V, population: 13.6 (2.2, 25.0), lag
    0
    EC+Ni, V: 11.9(-10.4, 43.2), lagO
    Ni: 19.0 (9.9, 28.2), lag 0
    Ni +EC: 17.3 (7.7, 26.9), lag 0
    Ni+ V: 15.5 (4.1,26.9), lag 0
    Ni + EC,V:14.9(3.4, 26.4), lag 0
    V: 27.5 (10.6, 44.4), lag 0
    V+EC: 23.1 (4.9, 41.4), lag 0
    V+Ni: 10.9 (-9.6, 31.5), lag 0
    V+EC, Ni: 8.1 (-13.3, 29.5), lag 0
    EC: 11.8 (-69.2, 92.8), lag 1
    EC: 21.0 (-46.6,  88.6), lag 2
    Ni: 20.6 (-15.5, 56.7), lag 1
    Ni: -2.3 (-32.5, 27.9), lag 2
    V: 34.0 (-31.2, 99.1),  lag 1
    V: 8.0 (-46.8, 62.7), lag 2
    Percent HS education: -17.4 (-46.8,
    11.9),  lag 0
    Median income:  21.3 (-20.0, 62.5), lag 0
    Percent black: 26.9 (-15.8, 69.6), lag 0
    Percent living in urban area: 34.4 (-
    29.0, 97.8), lagO
    Population: -4.3  (-13.3, 4.8), lag 0
    Notes: Interquartile ranges in percent
    HS education, median income,  percent
    black, percent living in urban area, and
    population are 5.2 %, $9,223,17.3%,
    11.0%, and 549,283 respectively.
    December 2009
                                     E-111
    

    -------
                  Study
                                               Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chan et al. (2007,1477871  Outcome: Cerebrovascular Emergency  Pollutant: PM25
                                        Admissions
                                                                            Averaging Time: 24 h
                                        Age Groups: 50+yr                  Mean (SD): 31.5 (16.0)
                                        Study Design: Time series
    Period of Study: Apr 1997-Dec 2002
    
    Location: Boston,  MA
                                        Statistical Analyses: GAM Poisosn
                                        Regression
    
                                        Covariates: Yr, mo, day of wk,
                                        temperature,  dew point
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: NR
    
                                        Lags Considered: 0-3 days
                                                                            Min:15.6
    
                                                                            Max: 200.6
    
                                                                            IQR: 19.7
    
                                                                            Monitoring Stations: 16
    
                                                                            Copollutant: 03, CO, S02, N02, PM1(
    
                                                                            Co-pollutant Correlation
                                                                            03: 0.33
                                                                            CO: 0.44
                                                                            S02: 0.51
                                                                            N02: 0.50
                                                                            PM10:0.61
                                        PM Increment: Interquartile Range
                                        (19.7 |jg/m3)
    
                                        Percent Change (Lower Cl, Upper Cl),
                                        p-value:
                                        Cerebrovascular Disease
                                        Lag 0:1.006 (0.993, 1.019)
                                        Lag 1:1.002 (0.990,1.014)
                                        Lag 2:1.015 (0.978, 1.052)
                                        Lag 3:1.021 (1.005, 1.037)
                                        Lag 3+ 03:1.009 (0.987, 1.031)
                                        Lag 3+ 00:1.014(0.993, 1.035)
                                        Lag 3+ 03+ 00:1.009(0.987, 1.031)
    
                                        Stroke
                                        Lag 0:0.931 (0.831, 1.031)
                                        Lag 1:0.936 (0.845, 1.027)
                                        Lag 2: 0.931 (0.820, 1.042)
                                        Lag 3: 0.991 (0.969, 1.013)
    
                                        Ischaemic stroke
                                        Lag 0:0.981 (0.907, 1.055)
                                        Lag 1:0.994 (0.920, 1.078)
                                        Lag 2: 0.960 (0.885, 1.035)
                                        Lag 3:1.059 (0.984, 1.134)
    
                                        Haemorrhagic stroke
                                        Lag 0: 0.870 (0.740, 1.010)
                                        Lag 1:0.882 (0.761, 1.003)
                                        Lag 2: 0.909 (0.810, 1.008)
                                        Lag 3: 0.921 (0.830, 1.012)	
    Reference: Chan et al. (2008, 0932971  Outcome (ICD-9): Emergency visits for  Pollutant: PM25
                                        ischaemic heart diseases (410-411,
    Period of Study: 1995-2002
    
    Location: Taipei Metropolitan area,
    Taiwan
                                        414), Cerebrovascular diseases (430-
                                        437), and COPD (493, 496)
    
                                        Age Groups: All
    
                                        Study Design: Time series
    
                                        N:NR
    
                                        Statistical Analyses: Poisson
                                        regression
    
                                        Covariates: Yr, mo, day of wk,
                                        temperature,  dewpoint temperature,
                                        PM,o, N02
    
                                        Season: All
    
                                        Dose-response Investigated: No
    
                                        Statistical Package: SAS version 8.0
    
                                        Lags Considered: 0- to 7-day lags
    Averaging Time: 24 h
    
    Mean ug/m3 (SD): NR
    
    Monitoring Stations: 1
    
    Copollutant (correlation): NR
    PM Increment: 19.7 pg/rri (IQR)
    
    OR [95% Cl]: In environmental
    conditions without dust storms (results
    only given for best-fitting model)
    
    Lag 6 days: 1.024 (1.004,1.044)
    Reference: Delfmo et al, (2008,
    1563901
    
    Period of Study: October
    2001-2003-November 2003
    
    Location: Southern California
                                        Outcome: Cardiovascular hospital
                                        admissions
    
                                        Study Design: Time series
    
                                        Statistical Analysis: Poisson
                                        regression with GEE
    
                                        Age Groups: All
    Pollutant: PM25
    
    Averaging Time: Hourly
    
    Mean (SD) Unit by county:
    Los Angeles
    Before Fires: 27.2 (12.4) pg/m3
    During Fires: 54.1 (21.0) pg/m3
    After Fires: 15.9 (5.5) pg/m
    Orange
    Before Fires: 23.2 (9.6) pg/m3
    During Fires: 64.3 (26.5) pg/m3
    After Fires: 15.5(10.2) pg/m3
    Riverside
    Before Fires: 32.7 (14.7) pg/m3
    During Fires: 42.1 (25.5) pg/m
    After Fires: 16.9(10.2) pg/m3
    San Bernadino
    Before Fires: 35.7 (16.6) pg/m3
    During Fires: 45.3 (28.7) pg/m3
    After Fires: 18.5 (8.3) pg/m
    San Diego
    Before Fires: 18.5 (6.7) pg/m3
    Increment: 10|jg/m
    
    Relative Rate (Min Cl, Max Cl)
    All Cardiovascular
    All Periods: 0.996 (0.989-1.003)
    Pre-Wildfire: 0.992 (0.976-1.009)
    Wildfire: 1.008 (0.999-1.018), p = 0.104
    Post-Wildfire: 0.991 (0.964-1.019),
    p = 0.955
    
    Ischaemic Heart Disease
    All Periods: 0.991 (0.980-1.003)
    Pre-Wildfire: 0.990 (0.963-1.017)
    Wildfire: 0.117 (0.990-1.024), p = 0.313
    Post-Wildfire: 0.989 (0.950-1.030),
    p = 0.976
    
    Congestive Heart Failure
    All Periods: 0.989 (0.974-1.004)
    Pre-Wildfire: 0.978 0.942-1.015)
    Wldfire: 1.016 (0.933-1.039), p = 0.096
    Post-Wildfire: 0.969 (0.914-1.027),
    p = 0.791	
    December 2009
                                                                        E-112
    

    -------
                   Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                                                              During Fires: 76.1 (66.6) pg/rrf
                                                                              After Fires: 14.2 (7.2) pg/nr
                                                                              Ventura
                                                                              Before Fires: 18.4 (8.3) pg/m3
                                                                              During Fires: 50.1 (50.5) pg/m3
                                                                              After Fires: 12.9 (4.3) pg/nf
                                                                              Copollutant (correlation): NR
                                                                              Cardiac Dysrhythmia
                                                                              All Periods: 0.980 (0.962-0.998)
                                                                              Pre-Wildfire: 0.979 (0.935-1.025)
                                                                              Wildfire: 0.989 (0.961-1.017), p = 0.721
                                                                              Post-Wildfire: 0.976 (0.912-1.044),
                                                                              p = 0.934
    
                                                                              Cerebrovascular Disease and Stroke
                                                                              All Periods: 1.019 (1.004-1.035)
                                                                              Pre-Wildfire: 1.015 (0.980-1.052)
                                                                              Wildfire: 1.016 (0.997-1.036), p = 0.971
                                                                              Post-Wildfire: 1.044 (0.987-1.104),
                                                                              p = 0.379
                                                                              Relative Rate (Min Cl, Max Cl) in
                                                                              relation to pre-wildfire period (1)
                                                                              All Cardiovascular: Wldfire, unadjusted
                                                                              for PM25: 0.958 (0.920-0.997)
                                                                              Wldfire, adjusted for PM25: 0.947
                                                                              (0.902-0.994)
                                                                              Post-wildfire, unadjusted for PM25:
                                                                              1.061 (1.006-1.119)
                                                                              Post-wildfire, adjusted for PM25:1.053
                                                                              (0.994-1.114)
                                                                              Ischaemic Heart Disease: Wldfire,
                                                                              unadjusted for PM25: 0.913 (0.852-
                                                                              0.978)
                                                                              Wldfire, adjusted for PM25: 0.905
                                                                              (0.832-0.985)
                                                                              Post-wildfire, unadjusted for PM25:
                                                                              1.029(0.943-1.123)
                                                                              Post-wildfire, adjusted for PM25:1.029
                                                                              (0.936-1.131)
                                                                              Congestive Heart Failure: Wldfire,
                                                                              unadjusted for PM25: 0.981 (0.817-
                                                                              0.972)
                                                                              Wldfire, adjusted for PM25: 0.911
                                                                              (0.819-1.014)
                                                                              Post-wildfire, unadjusted for PM25:
                                                                              1.113(0.997-1.242)
                                                                              Post-wildfire, adjusted for PM25:1.105
                                                                              (0.982-1.244)
                                                                              Cardiac Dysrhythmia: Wldfire,
                                                                              unadjusted for PM25: 0.968 (0.874-
                                                                              1.072)
                                                                              Wldfire, adjusted for PM25: 0.964
                                                                              (0.851-1.093)
                                                                              Post-wildfire, unadjusted for PM25:
                                                                              1.089(0.949-1.251)
                                                                              Post-wildfire, adjusted for PM25:1.057
                                                                              (0.914-1.223)
                                                                              Cerebrovascular Disease and Stroke:
                                                                              Wldfire, unadjusted for PM25:1.066
                                                                              (0.981-1.159)
                                                                              Wldfire, adjusted for PM25:1.017
                                                                              (0.922-1.123)
                                                                              Post-wildfire, unadjusted for PM25:
                                                                              1.013(0.907-1.132)
                                                                              Post-wildfire, adjusted for PM25:1.013
                                                                              (0.902-1.138)       	
    Reference: Dominici et al. (2006,
    Period of Study: 1999-2002
    
    Location: 204 U.S. counties,  located
    in: Alabama, Alaska, Arizona,  Arkansas,
    California, Colorado, Connecticut,
    Delaware, District of Columbia, Florida,
    Georgia,  Hawaii, Idaho, Illinois, Indiana,
    Iowa, Kansas, Kentucky, Louisiana,
    Maine,  Maryland, Massachusetts,
    Michigan, Minnesota,  Mississippi,
    Missouri,  Nevada,  New Hampshire,
    New Jersey, New Mexico,  New York,
    North Carolina, Ohio,  Oklahoma,
    Oregon, Pennsylvania, Rhode Island,
    South Carolina, Tennessee, Texas,
    Outcome (ICD-9): Daily counts of
    hospital admissions for primary
    diagnosis of heart failure (428), heart
    rhythm disturbances (426-427),
    Cerebrovascular events (430-438),
    ischemic heart disease (410-414, 429),
    peripheral vascular disease (440-448),
    chronic obstructive pulmonary disease
    (490-492), and respiratory tract
    infections (464-466, 480-487).
    
    Age Groups: >65 yr
    
    Study Design: Time series
    
    N: 11.5 million Medicare enrollees
    
    Statistical Analyses: Bayesian 2-stage
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (pg/m3) (IQR): 13.4 (11.3-15.2)
    
    Monitoring Stations: NR
    
    Copollutant (correlation): NR
    
    Other variables: Median of pairwise
    correlations among PM25 monitors
    within the same county for 2000: r =
    0.91 (IQR: 0.81-0.95)
    PM Increment: 10 pg/m (Results in
    figures; see notes)
    Percent increase in risk [95% PI]:
    Cerebrovascular disease (Lag 0):
    Age 65+: 0.81 [0.30, 1.32]
    Age 65-74: 0.91 [0.01, 1.82]
    Age 75+: 0.80 [0.21, 1.38]
    
    Peripheral vascular disease (Lag 0):
    Age 65+: 0.86 [-0.06, 1.79]
    Age 65-74:1.21 [-0.26,2.67]
    Age 75+: 0.86 [-0.39, 2.11]
    
    Ischemic heart disease (Lag 2):
    Age 65+: 0.44 [0.02, 0.86]
    Age 65-74: 0.37 [-0.22, 0.96]
    Age 75+: 0.52 [-0.01, 1.04]	
    December 2009
                                      E-113
    

    -------
                  Study
           Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
    Utah, Virginia, Washington, West
    Virginia, Wisconsin
    hierarchical models.
    
    First stage: Poisson regression (county-
    specific)
    
    Second stage: Bayesian hierarchical
    models, to produce a national avg
    estimate
    
    Covariates: Day of the week,
    seasonality, temperature, dew point
    temperature, long-term trends
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: R statistical
    software version 2.2.0
    
    Lags Considered: 0-2 days, avg of
    days 0-2
                                Heart rhythm disturbances (Lag 0):
                                Age 65+: 0.57 [-0.01,1.15]
                                Age 65-74: 0.46 [-0.63, 1.54]
                                Age 75+: 0.72 [0.02, 1.42]
    
                                Heart failure (Lag 0):
                                Age 65+: 1.28 [0.78, 1.78]
                                Age 65-74:1.21 [0.35, 2.07]
                                Age 75+: 1.36 [0.78, 1.94]
    
                                COPD (Lag 0):
                                Age 65+: 0.91  [0.91, 1.64]
                                Age 65-74: 0.42 [-0.64, 1.48]
                                Age 75+: 1.47 [0.54, 2.40]
    
                                Respiratory tract infection:
                                Age 65+: 0.92 [0.41, 1.43]
                                Age 65-74: 0.93 [0.04, 1.82]
                                Age 75+: 0.92 [0.32, 1.53]
                                Annual reduction in admissions
                                attributable to a 10 pg/m reduction in
                                daily PM25 level (95%  PI):
                                Cerebrovascular disease: Annual
                                number of admissions: 226,641
    
                                Annual reduction in admissions:  1836
                                [680, 2992]
    
                                Peripheral vascular disease: Annual
                                number of admissions: 70,061
    
                                Annual reduction in admissions:  602 [-
                                42,1254]
    
                                Ischemic heart disease: Annual number
                                of admissions: 346,082
    
                                Annual reduction in admissions:  1523
                                [69, 2976]
    
                                Heart rhythm disturbances: Annual
                                number of admissions: 169,627
    
                                Annual reduction in admissions:  967 [-
                                17,1951]
    
                                Heart failure: Annual number of
                                admissions: 246,598
    
                                Annual reduction in admissions:  3156
                                [1923, 4389]
    
                                COPD: Annual number of admissions:
                                108,812
    
                                Annual reduction in admissions:  990
                                [196,1785]
    
                                Respiratory tract infections: Annual
                                number of admissions: 226,620
    
                                Annual reduction in admissions:  2085
                                [929, 3241]
    
                                Notes: Fig 2: Point estimates and 95%
                                posterior intervals of the % change in
                                admissions rates per 10 pg/m3 (national
                                avg relative rates) for single lag (0,1,
                                and 2 days) and distributed lag models
                                for 0 to 2 days (total) for all outcomes.
                                Summary: Positive significant or
                                marginally significant associations
                                between PM2 5 and cerebrovascular
                                disease at Lag 0
    
                                Peripheral vascular disease at Lags 0
                                and 2
    
                                Ischemic heart disease at Lag 2
    
                                Heart rhythm disturbances at Lag 0
    December 2009
                                     E-114
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                                 Heart failure at Lag 0, Lag 2, and Lags
                                                                                                                 0-2
    
                                                                                                                 COPD at Lag 0, Lag 1, and Lags 0-2
    
                                                                                                                 and respiratory tract infections at Lag 2
                                                                                                                 and Lags 0-2.
    
                                                                                                                 Fig 3: Point estimates and 95%
                                                                                                                 posterior intervals of the % change in
                                                                                                                 admission rates per 10 pg/m3 (regional
                                                                                                                 relative rates). Summary: For
                                                                                                                 cardiovascular diseases, all estimates
                                                                                                                 in the Midwestern, Northeastern, and
                                                                                                                 Southern regions were positive, while
                                                                                                                 estimates in the other regions (South,
                                                                                                                 V\fest, Central, Northwest) were close to
                                                                                                                 0. For respiratory disease, there were
                                                                                                                 larger effects in the Central,
                                                                                                                 Southeastern, Southern, and Wfestern
                                                                                                                 regions than in the other regions.
    
                                                                                                                 Fig 4: Point estimates and 95%
                                                                                                                 posterior intervals of the % change in
                                                                                                                 admission per 10 pg/m3 (Eastern vs..
                                                                                                                 Wfestern regions): Summary: All
                                                                                                                 estimates for cardiovascular outcomes
                                                                                                                 were positive in the U.S. Eastern region
                                                                                                                 but not in the U.S. Wfestern region. The
                                                                                                                 estimates for respiratory tract infections
                                                                                                                 were larger in the Wfestern region than
                                                                                                                 in the Eastern region. The estimates for
                                                                                                                 CCPDwere positive in the both regions.
    Reference: Halonen et al. (2009,
    1803791
    Period of Study: 1998-2004
    Location: Helsinki, Finland
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Cardiovascular
    Hospitalizations & Mortality (ICD 10:
    100-99)
    
    Age Groups: 65+ yr
    Study Design: Time series
    N:NR
    Statistical Analyses: Poisson, GAM
    Covariates: Temperature, humidity,
    influenza epidemics, high pollen
    episodes, holidays
    Dose-response Investigated? No
    Statistical Package: R
    Lags Considered: lags 0-3 days; 5-day
    (0-4) mean
    
    
    
    
    
    
    
    Pollutant: PM25
    Averaging Time: Daily
    
    Mean (SD): NR
    Min:1.1
    26th percentile: 5.5
    60th percentile: 9.5
    76th percentile: 11. 7
    Max: 69.5
    Monitoring Stations: NR
    Copollutant:
    PMO.03, PM0.03-0.1,PM<0.1,
    PM<0. 10.29, PMio-25, CO, N02
    Co-pollutant Correlation
    PMO.03: 0.14
    PMO.03-0.1: 0.48
    PMO.1: 0.35
    PMO. 10.29: 0.88
    PMio-2.5: 0.25
    
    
    PM Increment: Interquartile Range
    Percent Change (Lower Cl, Upper
    Cl):
    All Cardiovascular Morality
    Lag 0:0.73 -0.66, 2.13
    Lag 1:0.74 -0.63,2.13
    Lag 2: 0.74 (-0.62, 2.11)
    Lag 3: 0.06 (-1.29, 1.43)
    5-day mean: 0.87 (-0.94, 2.70)
    Coronary Heart Disease HA
    Lag 0: -0.1 7 (-1.5.0, 1.18)
    Lag 1: -0.03 (-1.31, 1.26)
    Lag 2: -0.63 (-1.87, 0.62)
    Lag 3: 0.48 (-0.78, 1.76)
    5-day mean: 0.80 (-0.94 2.58)
    Stroke HA
    Lag 0: -0.99 (-2.78, 0.84)
    Lag 1:0.02 (-1.74, 1.82)
    Lag 2: -1.38 (-3.13, 0.40)
    Lag 3: -0.1 7 (-1.92, 1.61)
    5-day mean: -0.78 (-3.10, 1.60)
    Arrhythmia HA
    Lag 0:0.82 -1.03,2.68
    Lag 1:0. 18 -1.58, 1.97
    Lag 2: -0.09 (-1.82, 1.67)
    Lag 3: -0.48 (-2.22, 1.29)
    5-day mean: 0.16 (-2.16, 2.54)
                                                                                                                 *p < 0.05,
                                                                                                                              0.10
    December 2009
                             E-115
    

    -------
                   Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Host et al. (2008,1558521
    Period of Study: 2000-2003
    Location: Six French cities: Le Havre,
    Lille, Marseille, Paris, Rouen, and
    Toulouse
    Outcome (ICD-10): Daily
    hospitalizations for all cardiovascular
    (IOO-I99), cardiac (IOO-I52), and
    ischemic heart diseases (I20-I25), all
    respiratory diseases (JOO-J99),
    respiratory infections (J10-J22).
    Age Groups: For cardiovascular
    diseases: All ages, and restricted to >
    65 yr.  For all respiratory diseases: 0-14
    yr, 15-64 yr, and > 65 yr. For respiratory
    infections: All ages
    Study Design: Time series
    N: NR (Total population of cities:
    approximately  10 million)
    Statistical Analyses: Poisson
    regression
    Covariates: Seasons,  days of the wk,
    holidays, influenza epidemics, pollen
    counts, temperature, and temporal
    trends
    Season: NR
    Dose-response Investigated: No
    Statistical Package: MGCV package in
    R software (R 2.1.1)
    Lags  Considered: Avg of 0-1 days
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (6th -96th percentile):
    Le Havre: 13.8 (6.0-30.5)
    Lille: 15.9 (6.9-26.3)
    Marseille: 18.8 (8.0-33.0)
    Paris: 14.7 (6.5-28.8)
    Rouen: 14.4 (7.5-28.0)
    Toulouse: 13.8 (6.0-25.0)
    Monitoring Stations:
    13 total: 1 in Toulouse
    4 in Paris
    2 each in other cities
    Copollutant (correlation):
    PM10.2.5. Overall: r>0.6
    Ranged between r = 0.28 and
    r = 0.73 across the six cities.
    PM Increment: 10 pg/m increase, and
    a 27 pg/m3 increase (corresponding to
    the difference between the lowest of the
    5th percentiles and the highest of the
    95th percentiles of the cities'
    distributions)
    ERR (excess relative risk) Estimate [Cl]:
    For all cardiovascular diseases (10
    pg/m  increase): All ages: 0.9% [0.1,
    1.8]
    > 65 yr:  1.9% [0.9, 3.0]
    For all cardiovascular diseases (27
    pg/m3 increase): All ages: 2.5% [0.2,
    4.9]
    > 65 yr:  5.3% [2.6, 8.2]
    For ischemic heart diseases (27 pg/m3
    increase): All ages: 5.2% [-0.6,11.3]
    > 65 yr:  12.7% [6.3, 19.5]
    For cardiac diseases (10 pg/m3
    increase): All ages: 0.9% [-0.1, 2.0]
    > 65 yr:  2.4% [1.2, 3.7]
    For cardiac diseases (27 pg/m3
    increase): All ages: 2.5% [-0.3, 5.4]
    > 65 yr:  6.8% [3.3, 10.3]
    For ischemic heart diseases (10 pg/m3
    increase): All ages: 1.9 % [-0.2, 4.0]
    > 65 yr:  4.5% [2.3, 6.8]
    For all respiratory diseases (10 pg/m3
    increase): 0-14 yr: 0.4% [-1.2, 2.0]
    15-64 yr: 0.8% [-0.7, 2.3];
    > 65 yr:  0.5% [-2.0, 3.0]
    For all respiratory diseases (27 pg/m3
    increase): 0-14 yr: 1.1% [-3.1, 5.5]
    15-64 yr: 2.2% [-1.8, 6.4];
    > 65 yr:  1.3% [-5.3, 8.2]
                                                                                                                    For respiratory infections
                                                                                                                    increase): All ages: 2.5%
                                                                                                       10 pg/m3
                                                                                                       0.1,4.8]
                                                                                                                    For respiratory infections (27 pg/m3
                                                                                                                    increase): All ages: 7.0% [0.7,13.6]
    December 2009
                                      E-116
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Jalaludin et al. (2006,
    1894161
    
    Period of Study: Jan 1997-Dec 2001
    
    Location: Sydney, Australia
    Outcome (ICD-9): Cardiovascular
    disease (390-459), cardiac disease
    (390-429), ischemic heart disease (410-
    413) and cerebrovascular disease or
    stroke (430-438)
    
    Age Groups: 65+ yr
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: GAM, GLM
    
    Covariates: Temperature, humidity
    
    Season: Warm (Nov-Apr) and cool
    (May-Oct)
    
    Dose-response Investigated: No
    
    Statistical Package: S-Plus
    
    Lags Considered: 0-3 days
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (min-max): 9.5 (2.4-82.1)
    
    SD = 5.1
    
    Monitoring Stations: 14
    Copollutant (correlation):
    Warm
    BSP:r = 0.93
    PM,o:r = 0.89
    03:r = 0.57
    N02:r = 0.45
    CO: r  = 0.35
    S02:r = 0.27
    Cool
    BSP:r = 0.90
    PMi0:r = 0.88
    03:r = 0.05
    N02:r = 0.68
    CO: r  = 0.60
    S02:r = 0.46
    
    Other variables:
    Warm
    Temp: r = 0.24
    Pel humidity: r = -0.15
    Cool
    Temp: r = -0.04
    Pel humidity: r = 0.20	
    PM Increment: 4.8 pg/rri  (IQR)
    Percent Change Estimate [Cl]: All CVD
    Same-day lag: 1.26 [0.56,1.96]
    Avg 0-1 day lag: 0.85 [0.18,1.52]
    Cool (same-day lag): 2.23 [0.98,3.50]
    Warm (same-day lag): 0.73 [-0.05,1.52]
    Cardiac disease
    Same-day lag: 1.55 [0.74,2.38]
    Avg 0-1 day lag: 1.33 [0.54,2.13]
    Cool (same-day lag): 2.37 [0.87,3.89]
    Warm (same-day lag): 1.13 [0.22,2.04]
    Ischemic heart disease
    Same-day lag: 1.17 [-0.08,2.44]
    Avg 0-1 day lag: 1.24 [0.04,2.45]
    Cool (same-day lag): 0.57 [-1.74,2.94]
    Warm (same-day lag): 1.31 [-0.04,2.68]
    Stroke
    Same-day lag: -0.89 [-2.41,0.65]
    Avg 0-1 day lag:-1.08 [-2.54,0.41]
    Cool (same-day lag): 1.45 [-1.17,4.15]
    Warm (same-day lag): -2.19
    [-4.00.-0.36]
    Notes: All other lag-day ORs were
    provided, yet none were significant.
    Percent change in  ED attendance was
    also reported graphically (Fig 1-5).
    Reference: Jalaludin et al. (2006,
    1894161
    Period of Study: Jan 1997-Dec 2001
    
    Location: Sydney, Australia
    Outcome (ICD-9): Cardiovascular
    disease (390-459), cardiac disease
    (390-429), ischemic heart disease (410-
    413) and cerebrovascular disease or
    stroke (430-438)
    
    Age Groups: 65+ yr
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: GAM, GLM
    
    Covariates: Temperature, humidity
    
    Season:
    Warm (Nov-Apr) and cool (May-Oct)
    
    Dose-response Investigated: No
    
    Statistical Package: S-Plus
    
    Lags Considered: 0-3 days
    Pollutant: BS,P
    
    Averaging Time: 24 h
    
    Mean/104/m (min-max):
    0.26 (0.04-3.37)
    
    SD = 0.22
    
    Monitoring Stations: 14
    Copollutant (correlation):
    Warm
    PM25:r = 0.93
    PM,0:r = 0.82
    03:r = 0.48
    N02:r = 0.35
    CO: r = 0.33
    S02:r =  0.21
    
    Cool
    PM25:r = 0.90
    PM10:r = 0.75
    03:r = -0.08
    N02:r = 0.59
    CO: r = 0.62
    S02:r =  0.48
    
    Other variables:
    Warm
    Temp: r = 0.23
    Rel humidity: r = -0.04
    
    Cool
    Temp: r = -0.09
    Rel humidity: r = 0.36
    PM Increment: 0.18/104/m (IQR)
    Percent Change Estimate [Cl]:
    All CVD
    Same-day lag: 1.05 [0.44,1.66]
    Avg 0-1 day lag: 0.79 [0.20,1.38];
    Cool (same-day lag): 2.38 [1.15,3.62]
    Warm (same-day lag): 0.45 [-0.18,1.09]
    
    Cardiac disease
    Same-day lag: 1.34 [0.63,2.05]
    Avg 0-1 day lag: 1.13 [0.44,1.82];
    Cool (same-day lag): 2.50 [1.04,3.98]
    Warm (same-day lag): 0.80 [0.07,1.54]
    
    Ischemic heart disease
    Same-day lag: 0.91 [-0.17,2.02]
    Avg 0-1 day lag: 0.90 [-0.14,1.95];
    Cool (same-day lag): 0.52 [-1.74,2.83]
    Warm (same-day lag): 0.93 [-0.15,2.03]
    
    Stroke
    Same-day lag:-0.93 [-2.27,0.42]
    Avg 0-1 day lag:-0.82 [-2.11,0.49];
    Cool (same-day lag): 1.38 [-1.19,4.01];
    Warm (same-day lag): -1.85
    [-3.31,-0.36]
    Notes: All other lag-day ORs were
    provided, yet none were significant.
    Percent change in ED attendance was
    also reported graphically (Fig 1-5).
    December 2009
                                    E-117
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Lisabeth et al. (2008,
    1559391
    
    Period of Study: 2001-2005
    
    Location: Nueces County, Texas
    Outcome: Ischemic stroke and
    transient ischemic attacks (ICD codes
    not reported).
    
    Age Groups: 45+ yr
    
    Study Design: Time series
    
    N: 3,508 stroke/TIAs (2,350 strokes,
    and1,158TIAs)
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Temperature, day of week,
    temporal trends
    
    Season: All, but looked at potential
    effect modification by season (Summer:
    Jun-Sep; Non-summer: Oct-May)
    
    Dose-response Investigated: No
    
    Statistical Package: S-plus7.Q
    
    Lags Considered: Lags 0-5 days, and
    avg lag effect (0-5 days)
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Median ug/m3 (IQR): 7.0 (4.8-10.0)
    
    Monitoring Stations: 6
    
    Copollutant (correlation): NR
    PM Increment: 5.1 pg/rri  (IQR)
    
    RR Estimate [Cl]: Lag 0:1.03 (0.99,
    1.07)
    
    Lag 1:1.03 (1.00-1.07)
    
    All other lags and avg (lag 0-5) were not
    statistically or marginally significant.
    
    Adjusted for03: Lag 0:1.03 (0.99,1.07)
    
    Lag 1:1.03 (0.99-1.06)
    
    All other lags and avg (lag 0-5) were not
    statistically or marginally significant.
    
    Notes: Fig 3: % change in stroke/TIA
    risk associated with an IQR increase in
    PM25
    Reference: Metzger et al. (2004,
    0442221
    
    Period of Study: Aug 1998-Aug 2000
    
    Location: Atlanta Metropolitan area
    (Georgia)
    Outcome (ICD-9): Emergency visits for
    ischemic heart disease (410-414),
    cardiac dysrhythmias (427), cardiac
    arrest (427.5), congestive heart failure
    (428), peripheral vascular and
    cerebrovascular disease (433-437, 440,
    443.444, 451-453), atherosclerosis
    (440), and stroke (436).
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 4,407,535 emergency department
    visits for 1993-2000 (data not reported
    for 1998-2000)
    
    Statistical Analyses:  Poisson
    generalized linear modeling
    
    Covariates: Day of the wk, hospital
    entry and exit indicator variables,
    federally observed holidays, temporal
    trends, temperature, dew point
    temperature
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: SAS
    
    Lags Considered: 3-day ma, lags 0 -7
    Pollutant: PM25
    
    Averaging Time: 24 h
    Median ug/m3 (10%-90% range):
    PM25:17.8 (8.9, 32.3)
    PM2 5 water soluble metals: 0.021
    (0.006-0.061)
    PM25 acidity: 4.5 (1.9-1.07)
    PM25OC: 0.010
    (-0.001-0.045)
    PM25EC:4.1 (2.2-7.1)
    Monitoring Stations: 1
    
    Copollutant  (correlation):
    PM10:r =  0.84
    03:r = 0.65
    N02:r = 0.46
    CO: r = 0.44
    S02:r = 0.17
    PMi0.25:r=.43
    UFP:r = -0.16
    PM2 5 water-sol metals: r = 0.70
    PM25sulfates:r = 0.77
    PM25 acidity: r = 0.58
    PM25OC:r = 0.51
    PM25EC:r = 0.48
    oxygenated hydrocarbon: r = 31
    
    Other variables:
    Temperature: r  = 0.20
    Dew point: r = 0.00
    PM Increment: Approximately 1 SD
    increase: PM25:10|jg/m3
    PM2 5 water-sol metals: 0.03 pg/m3
    PM25sulfates:5|jg/m3
    PM2 5 acidity: 0.02 pequ/m3
    PM25OC:2|jg/m3
    PM25EC:1|jg/m3
    RR [95% Cl]: PM25 (3-day ma):
    
    All CVD: 1.033 [1.010, 1.056]
    Dysrhythmia: 1.015 [0.976,1.055]
    
    Congestive heart failure:
    1.055 [1.006-1.105]
    
    Ischemic heart disease:
    1.023 [0.983-1.064]
    
    Peripheral vascular and
    cerebrovascular disease:
    1.050 [1.008-1.093]
    
    PM;: water soluble metals (3-day
    ma):
    All CVD: 1.027(0.998,  1.056]
    Dysrhythmia: 1.031 [0.982,1.082]
    
    Congestive heart failure: 1.040
    [0.981-1.103]
    
    Ischemic heart disease: 1.000
    [0.951-1.051]
    
    Peripheral vascular and
    cerebrovascular disease: 1.043
    [0.991-1.098]
    
    PM25sulfates (3-day  ma):
    All CVD: 1.003 [0.968, 1.039]
    Dysrhythmia: 0.986 [0.926,1.048]
    
    Congestive heart failure: 1.009
    [0.938-1.085]
    
    Ischemic heart disease: 0.997
    [0.936-1.062]
    
    Peripheral vascular and
    cerebrovascular disease: 1.025
    [0.964-1.090]
    
    PM2 5 acidity (3-day ma):	
    December 2009
                                     E-118
    

    -------
                  Study                        Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                 All CVD: 0.994 [0.966, 1.022]
                                                                                                                 Dysrhythmia: 0.991  [0.942,1.043]
    
                                                                                                                 Congestive heart failure: 0.989
                                                                                                                 [0.930-1.052]
    
                                                                                                                 Ischemic heart disease: 0.992
                                                                                                                 [0.944-1.043]
    
                                                                                                                 Peripheral vascular and
                                                                                                                 cerebrovascular disease: 1.004
                                                                                                                 [0.955-1.056]
    
                                                                                                                 PM;: OC (3-day ma)
                                                                                                                 All CVD: 1.026 [1.006, 1.046]
                                                                                                                 Dysrhythmia: 1.008 [0.975,1.044]
    
                                                                                                                 Congestive heart failure: 1.048
                                                                                                                 [1.007-1.091]
    
                                                                                                                 Ischemic heart disease: 1.028
                                                                                                                 [0.994-1.064]
    
                                                                                                                 Peripheral vascular and
                                                                                                                 cerebrovascular disease:
                                                                                                                 1.026 [0.990-1.062]
                                                                                                                 hydrocarbons simultaneously.
    
                                                                                                                 PM;: OC (3-day ma):
                                                                                                                 All CVD: 1.020 [1.005, 1.036]
                                                                                                                 Dysrhythmia: 1.011  [0.985,1.037]
    
                                                                                                                 Congestive heart failure: 1.035
                                                                                                                 [1.003-1.068]
    
                                                                                                                 Ischemic heart disease: 1.019
                                                                                                                 [0.992-1.046]
    
                                                                                                                 Peripheral vascular and
                                                                                                                 cerebrovascular disease: 1.021
                                                                                                                 [0.994-1.049]
    
                                                                                                                 Results for Lags 0-7 expressed in
                                                                                                                 figures (see notes).
                                                                                                                 Notes: Fig 1: RR (95% Cl) for single-
                                                                                                                 day lag models for the association of
                                                                                                                 ER visits for CVD with daily ambient
                                                                                                                 PM2 5 and associated components.
    
                                                                                                                 Summary of Fig 1 results: Statistically
                                                                                                                 significant positive associations at Lag
                                                                                                                 0 and Lag  1 for PM25,  at Lag 0 for PM25
                                                                                                                 water soluble metals (inverse
                                                                                                                 association at Lag 7), at Lag 0, Lag 1,
                                                                                                                 and Lag 3  for organic and EC  (inverse
                                                                                                                 association at Lag 7).
    
                                                                                                                 Fig2:RR(95%)ofmultipollutant
                                                                                                                 models for the association of ER visits
                                                                                                                 for CVD with daily ambient air quality
                                                                                                                 measurements.
    
                                                                                                                 Summary of Fig 2 results: Positive
                                                                                                                 association after adjustment for N02,
                                                                                                                 CO, and oxygenated hydrocarbons,  but
                                                                                                                 attenuated when adjusted for total
                                                                                                                 carbon and null when adjusted for N02,
                                                                                                                 CO, total carbon, and oxygenated
    December 2009                                                     E-119
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Peng et al. (2008,1568501
    
    Period of Study: Jan 1999-Dec 2005
    
    Location: 108 U.S. counties in the
    following states: Alabama, Arizona,
    California, Colorado, Connecticut,
    District of Columbia, Florida, Georgia,
    Idaho, Illinois, Indiana, Kentucky,
    Louisiana, Maine, Maryland,
    Massachusetts, Michigan, Minnesota,
    Missouri, Nevada, New Hampshire,
    New Jersey, New Mexico, New York,
    North Carolina, Ohio, Oklahoma,
    Oregon, Pennsylvania, Rhode Island,
    South Carolina, Tennessee, Texas,
    Utah, Virginia, Washington,  West
    Virginia, Wisconsin
    Outcome (ICD-9): Emergency
    hospitalizations for: Cardiovascular
    disease, including heart failure (428),
    heart rhythm disturbances (426-427),
    cerebrovascular events (430-438),
    ischemic heart disease (410-414, 429),
    and peripheral vascular disease
    (440-448). Respiratory disease,
    including COPD (490-492) and
    respiratory tract infections (464-466,
    480-487)
    
    Age Groups: 65 + yr, 65-74, ,75 +
    
    Study Design: Time series
    
    N: ~12 million Medicare enrollees (3.7
    million CVD and 1.4 million RD
    admissions)
    
    Statistical Analyses: Two-stage
    Bayesian hierarchical models:
    Overdispersed Poisson models for
    county-specific data
    
    Bayesian hierarchical models to obtain
    national avg estimate
    
    Covariates: Day of the week, age-
    specific intercept, temperature, dew
    point temperature, calendar time,
    indicator for age of 75 yr or older. Some
    models were adjusted for PM10.2.5.
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: R version 2.6.2
    
    Lags Considered:  0-2 days
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean ug/m3 (IQR):
    All counties assessed: 13.5 (11.1-15.8)
    
    Counties in Eastern U.S.:
    13.8(12.3-15.8)
    
    Counties in Western  U.S.:
    11.1 (10.1-14.3)
    
    Monitoring Stations: At least 1 pair of
    co-located monitors (physically located
    in the same place) for PM10 and PM25
    per county
    
    Other variables: Median within-county
    correlations between monitors: r = 0.92
    PM Increment: 10 pg/m
    
    Percentage change [95% Cl]: CVD and
    RD (unadjusted for PM10-25): Lag 0:
    0.71 [0.45, 0.96]
    
    Lag 2: 0.44 [0.06, 0.82]
    
    Most values NR (see note)
    
    Notes: Effect estimates for PM10.2.5 (0-2
    day lags) are showing in Fig  2-5.
    
    Fig 2: Percentage change in  emergency
    hospital admissions for CVD  per 10
    pg/m3 increase in PM25 (single pollutant
    model and model adjusted for PMi0.25
    concentration)
    
    Fig 3: Percentage change in  emergency
    hospital admissions for RD per 10
    pg/m  increase in PM25 (single pollutant
    model and model adjusted for PMi0.25
    concentration)
    
    No significant associations between
    PM25 and cause-specific cardiovascular
    disease.
    Reference: Peters et al. (2005,
    1568591
    
    Period of Study: Feb 1999-Jul 31,
    2001
    
    Location: Germany: City of Augsburg,
    County Augsburg, and County Aichach-
    Friedlberg
    Outcome: Transmural or
    nontransmural acute Ml
    
    Age Groups: NR
    
    Study Design: Case-crossover and
    time series
    
    N: 851  Ml survivors
    
    Statistical Analyses: Conditional
    logistic regression for case-crossover
    element. Poisson regression for time
    series element.
    
    Covariates: Case-crossover: Season,
    temperature, day of the week, time
    series: trend, season, influenza,
    weather, and day of the week
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package:
    
    SAS, version 8.2
    
    Poisson: R, version 1.7.1
    
    Lags Considered: Lags 0-6 h, 0-5
    days
    
    Poisson: Single lagged days, 5-day,
    15-day, 30-day, and 45-day ma
    Pollutant: PM25
    
    Averaging Time: 1 h and 24 h
    Mean ug/m3 (range IQR/ median
    IQR):
    1-h avg: 16.3 (-6.9-355.2
    10.7-19.8
    14.5)
    24-h avg: 16.3 (6.1-58.5
    11.6-19.3
    14.9)
    Monitoring Stations: 1
    
    Copollutant (correlation):
    24-h avg:
    TNC:r = 0.37
    TSP:r = 0.89
    PM10:r=0.92
    CO:  r = 0.57
    N02:r = 0.67
    NO:  r = 0.59
    S02:r = 0.58
    03:r = -0.24
    Ihravg:
    TNC:r = 0.42
    CO:  r = 0.52
    N02:r = 0.58
    NO:  r = 0.50
    S02:r = 0.48
    03:r = -0.35
    Other variables:
    24-h avg: Temperature: r = 0.05
    1-h avg: Temperature: r = -0.01
    PM Increment: 1-h avg: 9.1 pg/m
    (IQR)
    
    24-h avg: 7.7 pg/m3 (IQR)
    
    OR [95% Cl]: Case-Crossover (control
    selection method (unidirectional with
    three control periods):
                                                                                                                  1-h avg: Lag 0:0.98 (0.88,1.10)
                                                                                                                  Lag 1:0.97
                                                                                                                  Lag 2: 0.93
               0.87, 1.09)
               0.83, 1.04)
                                                                                                                  Lag 3: 0.98 (0.88, 1.09)
                                                                                                                  Lag 4: 0.96
                                                                                                                  Lag 5: 0.94
               0.86, 1.07)
               0.84, 1.05)
                                                                                                                  Lag 6: 0.90 (0.80,1.01).
    
                                                                                                                  24-h avg: Lag 0:0.95 (0.83,1.080)
                                                                                                                  Lag 1:1.10  0.96,1.25)
                                                                                                                  Lag 2:1.18  1.03,1.34)
                                                                                                                  Lag 3:1.07 (0.94, 1.22)
                                                                                                                  Lag 4: 0.94 (0.83, 1.07)
                                                                                                                  Lag 5: 0.90 (0.79, 1.02)
                                                                                                                  Case-Crossover (control selection
                                                                                                                  method: bidirectional with 16 control
                                                                                                                  periods):
                                                                                                                  24-h avg: Lag 0:1.03 (0.94,1.12)
                                                                                                                  Lag 1:1.07
                                                                                                                  Lag 2:1.0'
               0.98,1.16)
               0.99, 1.17)
    Lag 3:1.01  (0.92,1.10)
    Lag 4: 0.96 (0.88, 1.04)
    Lag 5: 0.93 (0.85, 1.02)
    Lag 0-4 (IQR = 5.8): 1.03 (0.94, 1.14)
    Unidirectional: Model 1 (unadjusted):
    1.175(1.033,1.337)
    
    Model 2 (adjusted for day of week using
    indicator variables): 1.179(1.035,
    December 2009
                                     E-120
    

    -------
                   Study                        Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                     1343)
    
                                                                                                                     Model 3 (adjusted for temperature-
                                                                                                                     quadratic, linear air pressure): 1.170
                                                                                                                     (1.028, 1.333)
    
                                                                                                                     Model 4 (adjusted for temperature-
                                                                                                                     quadratic, linear air pressure, day of
                                                                                                                     week): 1.176 (1.031,1.341)
    
                                                                                                                     Model 5 (temperature-quadratic, air
                                                                                                                     pressure-quadratic, relative humidity-
                                                                                                                     quadratic, day of week using indicator
                                                                                                                     variables): 1.170 (1.026,1.336)
    
                                                                                                                     Model 6 (temperature-penalized spline,
                                                                                                                     4.4 df, linear air pressure, day of week
                                                                                                                     using indicator variables): 1.175 (1.030,
                                                                                                                     1.340
    
                                                                                                                     Model 7 (temperature-penalized spline,
                                                                                                                     4.4 df, linear air pressure, relative
                                                                                                                     humidity-penalized spline, 7.8 df, day of
                                                                                                                     week using indicator variables: 1.177
                                                                                                                     (1.030, 1.344)
    
                                                                                                                     Bidirectional (16 control periods): Model
                                                                                                                     1 (unadjusted): 1.077 (0.988,1.174)
    
                                                                                                                     Model 2 (adjusted for day of the week
                                                                                                                     using indicator variables): 1.078 (0.988,
                                                                                                                     1.175)
    
                                                                                                                     Model 3 (adjusted for temperature-
                                                                                                                     quadratic, linear air pressure): 1.060
                                                                                                                     (0.970,1.160)
    
                                                                                                                     Model 4 (adjusted for temperature-
                                                                                                                     quadratic, linear air pressure, day of the
                                                                                                                     week): 1.060 (0.969,1.160)
    
                                                                                                                     Model 5
    
                                                                                                                     (temperature-quadratic, air pressure-
                                                                                                                     quadratic, relative humidity-quadratic,
                                                                                                                     day of the week using indicator
                                                                                                                     variables): 1.065 (0.973,1.166)
    
                                                                                                                     Model 6 (temperature-penalized spline,
                                                                                                                     4.4 df, linear air pressure, day of the
                                                                                                                     week using indicator variables):  1.068
                                                                                                                     (0.976,1.168)
    
                                                                                                                     Model 7 (temperature-penalized spline,
                                                                                                                     4.4 df, linear air pressure, relative
                                                                                                                     humidity-penalized spline, 7.8 df, day of
                                                                                                                     the week using indicator variables:
                                                                                                                     1.077(0.983,1.179)
    
                                                                                                                     Bidirectional (4 control  periods): Model
                                                                                                                     1 (unadjusted): NR
    
                                                                                                                     Model 2 (adjusted for day of the week
                                                                                                                     by design):  1.049 (0.964,1.141)
    
                                                                                                                     Model 3 (adjusted for temperature-
                                                                                                                     quadratic, linear air pressure): NR
    
                                                                                                                     Model 4 (adjusted for temperature-
                                                                                                                     quadratic, linear air pressure, day of the
                                                                                                                     week): 1.032 (0.944,1.128)
    
                                                                                                                     Model 5 (temperature-quadratic, air
                                                                                                                     pressure-quadratic, relative humidity-
                                                                                                                     quadratic, day of the week by design):
                                                                                                                     1.033(0.945, 1.130)
    
                                                                                                                     Model 6 (temperature-penalized spline,
                                                                                                                     4.4 df, linear air pressure, day of the
                                                                                                                     week by design): 1.036(0.947,1.132)
    
                                                                                                                     Model 7 (temperature-penalized spline,
                 	4.4 df, linear air pressure, relative	
    December 2009                                                      E-121
    

    -------
                  Study                        Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                    humidity-penalized spline, 7.8 df, day of
                                                                                                                    the week by design): 1.039(0.950,
                                                                                                                    1.136)
    
                                                                                                                    Stratified: Model 1 (unadjusted): NR
    
                                                                                                                    Model 2 (adjusted for day of week by
                                                                                                                    design): 1.059 (0.972,1.154)
    
                                                                                                                    Model 3 (adjusted for temperature-
                                                                                                                    quadratic, linear air pressure): NR
    
                                                                                                                    Model 4 (adjusted for temperature-
                                                                                                                    quadratic, linear air pressure, day of
                                                                                                                    week):  1.047 (0.957,1.145)
    
                                                                                                                    Model 5 (temperature-quadratic, air
                                                                                                                    pressure-quadratic, relative humidity-
                                                                                                                    quadratic, day of week by design):
                                                                                                                    1.045(0.954,1.144)
    
                                                                                                                    Model 6 (temperature-penalized spline,
                                                                                                                    4.4 df, linear air pressure, day of week
                                                                                                                    by design): 1.054 (0.964,1.153odel7
                                                                                                                    (temperature-penalized spline,  4.4 df,
                                                                                                                    linear air pressure, relative
                                                                                                                    humidity-penalized spline, 7.8 df, day of
                                                                                                                    week by design): 1.056(0.965,1.156)
                                                                                                                    RR (95% Cl): Time series (24 h avg):
                                                                                                                    Lag 0: 0.97
                                                                                                                    Lag 1:1.04
               0.89, 1.07)
               0.96, 1.13)
                                                                                                                    Lag 2:1.07 (0.98,1.15)
                                                                                                                    Lag 3:1.03
                                                                                                                    Lag 4: 0.98
               0.95, 1.11)
               0.90, 1.07)
    Lag 5: 0.98 (0.90, 1.06)
    Lag 0-4:1.03 (0.94,1.12)
    Lag 0-14:1.03 (0.95,  1.13)
    Lag 0-29:1.09 (1.01,  1.18)
    Lag 0-44:1.08 (1.00,  1.17)
    Time series (OR [96% Cl]): Model 1
    (unadjusted): 1.059 (0.981,1.142)
    
    Model 2 (adjusted for day of week using
    indicator variables): 1.056 (0.979,
    1.140)
    
    Model 3 (adjusted for temperature-
    quadratic, linear air pressure): 1.062
    (0.982, 1.148)
    
    Model 4 (adjusted for temperature-
    quadratic, linear air pressure, day of
    week):  1.059  (0.979,1.146)
    
    Model 5 (temperature-quadratic, air
    pressure-quadratic, relative humidity-
    quadratic, day of week using indicator
    variables): 1.063 (0.981,1.151)
    
    Model 6 (temperature-penalized spline,
    4.4 df, linear air pressure, day of week
    using indicator variables): 1.065 (0.985,
    1.153)
    
    Model 7 (temperature-penalized spline,
    4.4 df, linear air pressure, relative
    humidity-penalized spline, 7.8 df, day of
    week using indicator variables: 1.069
    (0.988,1.157)
    December 2009                                                      E-122
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Pope et al.(2006, 0912461
    
    Period of Study: 1994-2004
    
    Location: Wasatch Front area, Utah
    Outcome: Myocardial infarction or
    unstable angina (ICD codes not
    reported)
    
    Age Groups: All, <65, 65+
    
    Study Design: Case-crossover
    
    N: 12,865 patients who underwent
    coronary arteriography
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature and dew
    point temperature
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: NR
    
    Lags Considered: 0- to 3-day lag, 2- to
    4-day lagged ma
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (ug/m3) (SD maximum):
    Ogden: 10.8 (10.6
    
    108)
    
    SLC Hawthorne: 11.3 (11.9
    
    94)
    
    Provo/Orem, Lindom: 10.1 (9.8
    
    82)
    
    Monitoring Stations: 3
    
    Copollutant (correlation): NR
    PM Increment: 10 pg/m
    
    Percent increase in risk [95% Cl]:
    Same-day increase in PM25 (Lag 0):
    Index Ml and unstable angina: 4.81
    [0.98-879]
    
    Subsequent Ml: 3.23 [-3.87,10.85]
    
    All acute coronary events: 4.46
    [1.07-7.97]
    
    All acute coronary events excluding
    observations using imputed PM25 data:
    4.24 [0.33-8.31]
    
    Stable presentation: -2.57 [-5.39, 0.34]
    
    Remaining results summarized in
    figures (see notes).
    
    Notes: Fig 1: Percent increase in risk
    (and 95% Cl) of acute coronary events
    associated with 10 pg/m3 of PM25 for
    different lag structures.
    
    Summary of Fig 1:  Positive, statistically
    significant association seen for Lag 0,
    Lag 1 and 2, 3, and 4 day ma. Positive
    but non-statistically significant
    associations seen for Lags 2 and 3.
    
    Fig 2: Percent increase in risk (and 95%
    Cl) of acute coronary events associated
    with 10 pg/m3 of PM25 stratified by
    various characteristics.
    Reference: Pope et al. (2008,1919691
    
    Period of Study: 1994-2006
    
    Location: Ogden, Salt Lake City, &
    Provo/Orem, Utah
    Outcome: Heart Failure
    Hospitalizations
    
    Age Groups: NR
    
    Study Design: Case-crossover
    
    N: 2,618
    
    Statistical Analyses: Conditional
    Logistic Regression
    
    Covariates: Age, sex, length of stay,
    temperature, pressure, clearing index,
    day of the week, seasonality, and long-
    term trends
    
    Season: Adjusted for long-term trends
    to account for season
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 0- to 28-day ma.
    Pollutant: PM25
    
    Averaging Time: NR
    
    Mean (SD):
    Ogden: 10.6(9.9)
    
    SLC, Hawthorne: 11.1  (11.2)
    
    Provo/Orem, Lindon: 10.1 (9.3)
    
    Max:
    Ogden: 108
    
    SLC, Hawthorne: 94
    
    Provo/Orem, Lindon: 82
    
    Monitoring Stations:  NR
    
    Copollutant: PM10
    PM Increment: 10 pg/m
    
    Percent Increase: (Lower Cl, Upper
    Cl):
    All HF Admissions
    All: 13.1 (1.3,26.2)*
    Men: 13.4 (-1.7, 30.7)|
    Vtomen: 12.7 (-5.1,33.9)
    Age <65yr: 3.5 (-13.5, 23.8)
    Age >65yr: 19.6 (4.0, 37.5)*
    Length of stay 0-2 days:
    24.4 (-0.8, 56.0) J
    Length of stay 3-7 days:
    10.8 (-4.6, 28.7)
    Length of stay 8+ days:
    6.5 (-15.9, 34.8)
    
    First HF Admissions: 2.1 (-11.3,17.5)
    Subsequent HF Admits: 32.4 (10.7,
    58.4) T
    
    All HF Admissions
    All: 32.4(10.7,58.4)1
    Men: 29.2 (2.7, 62.6)*
    V\fomen:41.5(5.4, 89.9)*
    Age<65yr:-3.1 (-26.5,27.8)
    Age >65yr: 64.1 (28.6,109)t
    Length of stay 0-2 days:
    68.9(12.5,154)*
    Length of stay 3-7 days:
    35.7 (5.9, 73.9)*
    Length of stay 8+ days:
    2.6 (-28.5, 47.1)
    *p<0.05, tp<0.01,tp<0.10
    December 2009
                                    E-123
    

    -------
    Study
    Reference: Sarnat et al. (2008,
    0979721
    Period of Study: Nov 1998-Dec 2002
    Location: Atlanta (Georgia)
    metropolitan area
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome (ICD-9): Cardiovascular
    disease ED visits: Ischemic heart
    disease (41 0-41 4), cardiac
    dysrhythmias (427), congestive heart
    failure (428), and peripheral vascular
    and cerebrovascular disease (433-437,
    440, 443-444, 451-453)
    Age Groups: All
    Study Design: Time series
    N: >4.5 million emergency department
    wjcjtc
    VIolLo
    Statistical Analyses: Poisson
    generalized linear models
    Covariates: Day of the week, holidays,
    hospital, long-term trends, temperature,
    dew point temperature
    
    Season: All, warm season (Apr 15-Oct
    14), and cool season (Oct 15-Apr 14).
    
    Dose-response Investigated: No
    Statistical Package: NR
    
    Lags Considered: 0-day lag
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Concentrations1
    Pollutant: PM25
    
    Averaging Time: 24 h
    Mean (ug/m3) (median 10th-90th
    percentile):
    Total PM25:
    Cool season: 15.8 (14.3
    7.5-25.5).
    Warm season: 18.2(17.0
    9.1-29.0)
    PM25 EC:
    Cool: 1.7(1.4
    0.6-3.3).
    Warm: 1.4 (1.3
    0.6-2.5)
    PM25Zn(ng/m3):
    Cool: 15.7 (11. 7
    A fi "30. OA
    4.0-oU.z)
    Warm: 10.9 (8.5
    -3 -5 on <-)\
    o.o-zU.z)
    PM25K(ng/m3):
    Cool: 63.0 (53.9
    24.3-114.2)
    Warm: 52.7 (43.3
    23.2-93.5)
    
    PM25Si (ng/m3):
    Cool: 67.7 (54.1
    24.3-123.5).
    Warm: 110.9 (89.0
    32.9-186.3)
    PM25S042":
    Cool: 3.4 (0.6
    1.5-5.8).
    Warm: 6.0 (5.2
    2.3-10.8)
    
    PM25NOr:
    Cool: 1.4 (1.2
    0.5-2.6).
    Warm: 0.7 (2.9
    0.3-1.2)
    PM25Se(ng/m3):
    Cool: 1.4(1.1
    0.4-3.0).
    Warm1 1 2 (09
    0.4-2.7) '
    PM25OC:
    Cool: 4.6 (3.9
    1.9-8.0)
    Warm: 4.0 (3.7
    2.1-6.4)
    Monitoring Stations: 1
    Copollutants: NR
    Effect Estimates (95% Cl)
    PM Increment: IQR (specific values not
    given)
    Risk ratio [95% Cl]: CVD (Lag 0): All
    seasons: Total PM25: 1.022 [1.007,
    1.038]
    PM25 EC: 1.02 [1.013-1.037]
    PM2.5 zinc: 1.013 [1.005-1.022]
    PM2.5 potassium: 1.030 [1.018-1.042]
    PM25 silicon: 1.008 [1.00-1. 01 6]
    
    PM25 sulfate: 1.007 [0.994-1.019]
    PM25 nitrate: 1.002 [0.990-1.014]
    PM25 selenium: 1.002 [0.991-1. 012]
    PM25OC: 1.024 [1.013-1.035]
    
    Cool season: Total PM25: 1.028
    [1.012-1.044]
    
    PM25 EC: 1.029 [1.015-1.044]
    PM2.5 Zinc: 1.012 [1.002-1.022]
    
    PM25K: 1.037 [1.021-1.054]
    
    PM2 5 Si: 1.022 [1.002-1. 043]
    
    PM2.5 sulfate: 1.014 [0.991-1.037]
    PM25 nitrate: 1.006 [0.993-1.019]
    PM25Se: 1.012 [0.997-1. 027]
    PM25OC: 1.027 [1.013-1.040]
    
    Warm season: Total PM25: 1.006
    [0.990-1.022]
    
    PM2.5 EC: 1.021 [1.000-1.043]
    PM2.5 Zinc: 1.017 [1.002-1.033]
    PM2 5 K: 1.024 [1.007-1. 041]
    PM2.5 Si: 1.005 [0.996-1.014]
    PM25 sulfate: 1.001 [0.988-1.015]
    
    PM2 5 nitrate: 1.000 [0.969-1. 033]
    
    PM25Se: 0.996 [0.981-1. 011]
    PM25OC: 1.027 [1.004-1.051]
    
    
    
    
    
    
    December 2009
    E-124
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Schreuder et al. (2006,
    0979591
    Period of Study: Sep 1995-May 2002
    Location: Spokane, WA
    Outcome: Cardiac HA
    Age Groups: NR
    Study Design: Time series
    Statistical Analyses: GAM Poisosn
    Regression
    Covariates: Season, temperature,
    relative humidity, day of week
    Dose-response Investigated? No
    Statistical Package: S-Plus
    Lags Considered: 0-1 day
    Pollutant: PM25 (ng/rri)
    Averaging Time: 24 h
    Arithmetic Mean: 10,580
    Geometric Mean: 8,790
    Min: 930
    Max: 43,230
    IQR:
    Entire period: 7.7 pg/m3
    Heating season: 10.1|jg/m
    Non-heating season: 5.5|jg/m3
    Monitoring Stations: NR
    Copollutant: NR
    Co-pollutant Correlation: NR
    PM Increment: Interquartile Range
    Relative Risk (Lower Cl, Upper Cl):
    Entire Period, Lag 0:1.008 (0.985,
    1.032)
    Entire Period, Lag 1:1.000 (0.978,
    1.023)
    Heating Season, Lag 1:1.015 (0.968,
    1.063)
    Non-Heating Season, Lag 1: 0.995
    (0.969, 1.021)
    December 2009
                                   E-125
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Sullivan et al. (2005,
    1094181
    
    Period of Study: 1988-1994
    
    Location: King County, Washington
    Outcome: Acute Ml
    
    Age Groups: All, <50, 50-59, 70+
    
    Study Design: Case-crossover
    
    N: 5793 cases of acute Ml (5793 case
    days and 20,134 referent exposure
    days from these case individuals)
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Relative humidity,
    temperature, season, day of week
    
    Season: All, and also conducted
    stratified analysis by season of event
    (heating season: Nov-Feb
    
    nonheating season: Mar-Oct)
    
    Dose-response Investigated: No
    
    Statistical Package: SAS version 8.0
    and SPSS version 10
    
    Lags  Considered: Lag 1 and Lag 2 for
    24-h avg
    Pollutant: PM25
    
    Averaging Time:
    1 h, 2 h, 4 h, and 24 h
    
    Summary of PM2 51 h before Ml onset:
    
    Mean (ug/m3) (median IQR, 90th
    percentile range):
    12.8(8.6
    
    5.3-15.9
    
    27.3
    
    2.0-147)
    
    Monitoring Stations: 3
    
    Copollutant (correlation):
    1-havg:
    PMi0:r = 0.78
    
    CO: r = 0.47
    
    SO,: r = 0.16
    PM Increment: 10 pg/m
    
    Odds ratio [96% Cl]:
    
    1-h Averaging Time: 1.01 [0.98,1.05]
    
    2-h Averaging Time: 1.01 [0.97,1.05]
    
    4-h Averaging Time: 1.02 [0.98,1.04]
    
    24-h Averaging Time: 1.02 [0.98,1.07]
    
    Association between PM25 (24 h)
    lagged 1 or 2 days non-significant (data
    not shown)
    
    Season (1-h avg): Heating: 1.01
    [0.98-1.05]
    
    Nonheating: 0.99 [0.91-1.09]
    Age (1-h avg): <50yr: 1.04 [0.95,1.14]
    50-60 yr: 0.99 [0.94,  1.05]
    70+yr: 1.03 [0.98,1.08]
    Age (24-h  avg): <50yr: 1.07 [0.98,1.19]
    50-69 yr: 0.99 [0.93,  1.06]
    70+yr: 1.04 [0.99,1.11]
    Sex (1-h avg): Men: 1.02 [0.98,1.06]
    Women: 1.00 [0.95,1.06]
    Sex (24-h  avg): Men: 1.03 [0.99,1.08]
    Women: 1.00 [0.94,1.07]
    Race (1-h  avg): White: 1.01 [0.97,1.04]
    Nonwhite:  1.06 [0.97,1.17]
    Race (24-h avg):  White: 1.01 [0.97,
    1.06]
    Nonwhite:  1.10 [0.99,1.23]
    Smoking status (1-h avg): Current: 0.99
    [0.93,1.06]
    Nonsmoker: 1.03 [0.97,1.08]
    Smoking status (24-h avg): Current:
    0.99 [0.95,1.14]
    Nonsmoker: 1.03 [0.98,1.09]
    Survivor of Ml* (1-h avg): Yes: 1.02
    [0.98, 1.06]; No: 0.96 [0.86,  1.08]
    Survivor of Ml * (24-h avg): Yes: 1.03
    [0.98, 1.07]; No: 0.97 [0.85,  1.10]
    Previous congestive  heart failure (1 h
    avg): Yes:  1.06 [0.97,1.16]; No: 1.00
    [0.97, 1.04]
    Previous congestive  heart failure (24-h
    avg): Yes:  1.08 [0.97,1.2]; No: 1.00
    [0.97, 1.04]
    Previous Ml (1-h avg): Yes: 1.03 [0.97,
    1.1]; No: 1.01 [0.96,1.06]
    Previous Ml (24-h avg): Yes: 1.04 [0.97,
    1.17]; No:  1.02 [0.98, 1.08]
    Hypertension (1-h avg): Yes: 1.02 [0.97,
    1.07]; No:  1.01  [0.96, 1.06]
    Hypertension (24-h avg): Yes: 1.02
    [0.97, 1.07]; No: 1.02 [0.97,  1.08]
    Diabetes mellitus (1-h avg): Yes: 1.06
    [0.98, 1.14]; No: 1.01 [0.97,  1.05]
    Diabetes mellitus (24-h avg): Yes:  1.04
    [0.95, 1.14]; No: 1.01 [0.97,  1.06]
    'Compares those who survive
    hospitalization (yes) with those who
    died in hospital from complications of
    December 2009
                                     E-126
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Symons et al. (2006,
    0912581
    Period of Study: Apr-Dec 2002
    
    Location: Baltimore, Maryland
    Outcome: Congestive heart failure
    
    Age Groups: All
    
    Study Design: Case-crossover
    
    N: 125 patients
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature and humidity
    
    Season: NR
    
    Dose-response Investigated: Yes
    
    Statistical Package: SAS and S-Plus
    
    Lags Considered: 0-3 days (single and
    cumulative)
    Pollutant: PM25
    
    Averaging Time: 8 h & 24 h
    
    Mean (min-max):
    
    8h
    
    17.0(0.1-111.9)
    
    SD=12.7
    
    24 h
    
    16.0(3.5-69.2)
    
    SD=10.0
    
    Monitoring Stations: 8
    
    Copollutant (correlation): NR
    PM Increment: 9.2 pg/m3 (IQR)
    
    RR Estimate [Cl]:
    8 h (participant's onset period)
    Same-day lag: 0.87 [0.69,1.09]
    1-day lag: 0.96 [0.78,1.18
    2-day lag: 1.09 [0.91,1.30
    3-day lag: 0.99 [0.79,1.23]
                                                                                                               Cumulative 1-day lag: 0.89
                                                                                                               Cumulative 2-day lag: 0.99
                            0.67,1.16]
                            0.74,1.33]
                                                                                                               Cumulative 3-day lag: 0.98 [0.70,1.36]
    
                                                                                                               24 h avg
                                                                                                               Same-day lag: 0.81 [0.65,1.01]
                                                                                                               1-day lag: 0.90 [0.74,1.11]
                                                                                                               2-day lag: 0.85 [0.68,1.07]
                                                                                                               3-day lag: 0.86 [0.70,1.05]
                                                                                                               Cumulative 1-day lag: 0.82
                            0.64,1.04]
                            0.57,1.01]
                                                                                                               Cumulative 2-day lag: 0.76
                                                                                                               Cumulative 3-day lag: 0.70 [0.51,0.97]
                                                                                                               Notes: |3 coefficients presented in Fig 5
    Reference: Tolbert et al. (2007,
    0903161
    
    Period of Study: Aug 1998-Dec 2004
    
    Location: Atlanta Metropolitan area,
    Georgia
    Outcome (ICD-9):
    Combined CVD group, including:
    
    Ischemic heart disease (410-414),
    cardiac dysrhythmias (427), congestive
    heart failure (428), and peripheral
    vascular and cardiovascular disease
    (433-437, 440, 443-445, and 451-453)
    
    Age Groups: All
    
    Study Design: Time series
    
    N:NR for 1998-2004.
    
    For 1993-2004:10,234,490 ER visits
    (283,360 and 1,072,429 visits included
    in the CVD and RD groups,
    respectively)
    
    Statistical Analyses: Poisson
    generalized linear models
    
    Covariates: Long-term temporal trends,
    season (for RD outcome), temperature,
    dew point, days of week, federal
    holidays, hospital entry and exit
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: SAS version 9.1
    
    Lags Considered: 3-day maflag 0 -2)
    Pollutant: PM25
    
    Averaging Time: 24 h
    Mean (ug/m3) (median IQR, range,
    10th -90th percentiles):
    PM25:17.1 (15.6
    11.0-21.9
    0.8-65.8
    7.9-28.8).
    
    PM25sulfate:4.9(3.9
    2.4-6.2
    0.5-21.9
    1.7-9.5).
    
    PM25OC:4.4(3.8
    2.7-5.3
    0.4-25.9
    2.1-7.2).
    
    PM25EC:1.6(1.3
    0.9-2.0
    0.1-11.9
    0.6-3.0).
    
    PM25 water-soluble metals: 0.030
    (0.023
    0.014-0.039
    0.003-0.202
    0.009-0.059)
    Monitoring Stations: 1
    Copollutant (correlation):
    Between PM25and:
    PM,0:r = 0.84
    03:r = 0.62
    N02:r = 0.47
    CO: r = 0.47
    S02:r = 0.17
    PM10.25:r = 0.47
    PM25S04:r = 0.76
    PM25EC:r = 0.65
    PM25OC:r = 0.70
    PM25TC:r = 0.71
    P M2 5 water-sol metals: r = 0.69
    OHC:r = 0.50
    
    Between PM25 S04 and: PM,0: r = 0.69
    03:r = 0.56
    N02:r = 0.14
    CO: r = 0.14
    S02:r = 0.09
    PMi0.25:r = 0.32
    PM25:r = 0.76
    PM25EC:r = 0.32
    PM25OC:r = 0.33	
    PM Increment:
    PM25:10.96 pg/m3 (IQR)
    PM25sulfate:3.82|jg/ms(IQR)
    PM25total carbon: 3.63 pg/m3 (IQR)
    PM25OC:2.61 pg/m3(IQR)
    PM25EC:1.15|jg/m3(IQR)
    PM25 water-soluble metals: 0.03 pg/m3
    (IQR)
    Risk ratio [95% Cl] (single pollutant
    models):
    PM25:
    CVD: 1.005 [0.993-1.017]
    PM25sulfate:
    CVD: 0.999 [0.987-1.011]
    PM25total carbon:
    CVD: 1.016 [1.005-1.026]
    PM25OC:
    CVD: 1.015 [1.005-1.026]
    PM25EC:
    CVD: 1.015 [1.005-1.025]
    PM2 5 water-soluble metals:
    CVD: 1.009 [0.997-1.021]
    Notes: Results of selected multi-
    pollutant models for cardiovascular
    disease are presented in Fig 1.
    
     Fig 1: PM25 total carbon adjusted for
    CO, N02, or N02+C0
    
    Summary of results: PM2 5 total carbon
    continued to have a positive, statistically
    significant association with CVD after
    adjustment for N02 but not after
    adjustment
    December 2009
                                    E-127
    

    -------
                 Study                     Design & Methods               Concentrations1            Effect Estimates (95% Cl)
                                                                     PM25TC:r = 0.34
                                                                     PM2 5 water-sol metals: r = 0.65
                                                                     OHC:r = 0.47
    
                                                                     Between PM2 5 EC and:
                                                                     PM10:r = 0.61
                                                                     03:r = 0.40
                                                                     N02:r = 0.64
                                                                     CO: r = 0.66
                                                                     S02:r = 0.22
                                                                     PMi0.25:r = 0.49
                                                                     PM25:r = 0.65PM25
                                                                     S04:r = 0.32
                                                                     PM25OC:r = 0.82
                                                                     PM25TC:r = 0.91
                                                                     PM2 5 water-sol metals: r = 0.52
                                                                     OHC:r = 0.35
    
                                                                     Between PM25 OC and:
                                                                     PMi0:r = 0.65
                                                                     03:r = 0.54
                                                                     N02:r = 0.62
                                                                     CO: r = 0.59
                                                                     S02:r = 0.17
                                                                     PM10.25:r = 0.49
                                                                     PM25:r = 0.70
                                                                     PM25S04:r = 0.33
                                                                     PM25EC:r = 0.82
                                                                     PM25TC:r = 0.98
                                                                     P M2 5 water-sol metals: r = 0.49
                                                                     OHC:r = 0.37
    
                                                                     Between PM25 total carbon and:
                                                                     PM10:r = 0.67
                                                                     03:r = 0.52
                                                                     N02:r = 0.65
                                                                     CO: r = 0.63
                                                                     S02:r = 0.19
                                                                     PM10.25:r = 0.51
                                                                     PM25:r = 0.71
                                                                     PM25S04:r = 0.34
                                                                     PM25EC:r = 0.91
                                                                     PM25OC:r = 0.98
                                                                     PM2 5 water-sol metals: r = 0.52
                                                                     OHC:r = 0.38
    
                                                                     Between PM25 water-soluble metals
                                                                     and: PM,0:r = 0.73
                                                                     03:r = 0.43
                                                                     N02:r = 0.32
                                                                     CO: r = 0.35
                                                                     S02:r = 0.06
                                                                     PMi0.25:r = 0.50
                                                                     PM25:r = 0.69
                                                                     PM25S04:r = 0.65
                                                                     PM25EC:r = 0.52
                                                                     PM25OC:r = 0.49
                                                                     PM25TC:r = 0.52	
    December 2009                                              E-128
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Villeneuve et al. (2006,
    0901911
    
    Period of Study: Apr 1992-Mar 2002
    
    Location: Edmonton, Canada
    Outcome (ICD-9): Stroke (430-438),
    including ischemic stroke (434-436),
    hemorrhagic stroke (430,432), and
    transient ischemic attacks (TIA) (435).
    
    Age Groups: 65+ yr
    
    Study Design: Case-crossover
    
    N: 12,422 visits
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature and relative
    humidity
    
    Season: Summer (Apr-Sep), winter
    (Oct-Mar)
    
    Dose-response Investigated: No
    
    Statistical Package: SAS (PHREG)
    
    Lags Considered: 0,1, and 3 days
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean ug/m3 (SD):
    All yr: 8.5 (6.2)
    Summer: 8.7 (7.1)
    Winter: 8.3 (5.2)
    Monitoring Stations: 3
    
    Copollutant (correlation):
    Allyr
    S02:r = 0.22
    N02:r = 0.41
    CO: r = 0.43
    03-mean:r = -0.07
    Os-max: r = 0.07
    PMi0:r = 0.79
    
    Summer
    S02:r = 0.20
    N02:r = 0.52
    CO: r = 0.42
    Oj-mean: r = 0.11
    03-max: r = 0.34
    PM10:r = 0.85
    
    Winter
    S02:r = 0.28
    N02:r = 0.57
    CO: r = 0.71
    Os-mean: r = -0.45
    Os-max: r = -0.35
    PM10:r = 0.70
    PM Increment: pg/m  (IQR)
    All yr: 6.3
    Summer: 6.5
    Wnter: 6.0
    Adjusted OR Estimate [Cl]:
    Acute ischemic stroke
    Allyr: Same-day lag: 1.00 [0.96,1.04]
    1-day lag: 1.00 [0.96,1.05]
    3-day lag: 1.01 [0.96,1.06]
    Summer: Same-day lag: 0.96
    [0.90,1.03]
    1-day lag: 1.01 [0.94,1.07]
    3-day lag: 0.98 [0.89 [1.07]
    Wnter: Same-day lag: 1.04 [0.99,1.10]
    1-day lag: 1.01 [0.96,1.07]
    3-day lag: 1.05 [0.98,1.13]
    
    Hemorrhagic stroke
    All yr: Same-day lag: 0.99 [0.90,1.08]
    1-day lag: 1.07 [0.98,1.16]
    3-day lag: 1.05 [0.93,1.19]
    Summer: Same-day lag: 0.99
    [0.86,1.15]
    1-day lag: 1.12 [0.97,1.30]
    3-day lag: 1.08 [0.88,1.31]
    Wnter: Same-day lag: 1.04 [0.92,1.18]
    1-day lag: 1.08 [0.97,1.20]
    3-day lag: 1.11 [0.94,1.31]
    
    Transient cerebral ischemic attack
    All yr: Same-day lag: 0.98 [0.93,1.03]
    1-day lag: 0.99 [0.95,1.04]
    3-day lag: 0.96 [0.90,1.03]
    Summer: Same-day lag: 1.00
    [0.92,1.08]
    1-day lag: 1.03 [0.95,1.12]
    3-day lag: 0.98 [0.88,1.09]
    Wnter: Same-day lag: 0.97 [0.90,1.05]
    1-day lag: 0.97 [0.91,1.04]
    3-day lag: 0.94 [0.86,1.03]
    Notes: Adjusted ORs are provided for
    an IQR increase in the 3-day mean in
    Fig 1-4 for single and two-pollutant
    models.
    Reference: Zanobetti and Schwartz
    (2006, 0901951
    
    Period of Study: 1995-1999
    
    Location: Boston Metropolitan area
    Outcome (ICD-9): Myocardial infarction
    (410) or pneumonia (480-487)
    
    Age Groups: 65+ yr
    
    Study Design: Case-crossover
    
    N: 15,578 patients admitted for Ml and
    25,857 admitted for pneumonia
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature, day of the
    week.
    
    Season: All,  and also tested for
    interaction by warm (Apr-Sep) vs.. cold
    season
    
    Dose-response Investigated: No
    
    Statistical Package: SAS version 8.2
    (PROC PHREG)
    
    Lags Considered: Lag 0,  and mean of
    lags 0 -1
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Median (ug/m3) (IQR 5th-95th
    percentile):
    
    11.1 (7.23-16.14
    
    3.87-26.31)
    
    Monitoring Stations: 1
    
    Copollutant (correlation):
    
    BC:r = 0.66
    
    N02:r = 0.55
    
    CO: r = 0.52
    
    03:r = 0.20
    
    PM non-traffic: r = 0.74
    PM Increment: Difference between the
    90th and 10th percentile for PM2 5
    
    Myocardial infarction cohort (Lag 0):
    17.17  pg/m3
    
    Myocardial infarction cohort (Lag 0-1):
    16.32  pg/m3
    
    Pneumonia cohort (Lag 0): 17.14 pg/m3
    
    Pneumonia cohort (Lag 0): 16.32 pg/m3
    
    Percentage (%) increase in risk [95%
    Cl]:
    Myocardial infarction cohort:
    Lag 0:8.50 (1.89-14.43)
    Lag 0-1: 8.65 (1.22-15.38)
    
    Pneumonia cohort:
    Lag 0:6.48 (1.13-11.43)
    Lag 0-1: 5.56 (-0.45, 11.27)
    Notes: Assessed for effect modification
    by season. Results are reported in  Fig
    2. Summary of results: PM25 is
    associated with pneumonia
    hospitalization in the cold season but
    not the hot season.  PM2 5 is associated
    with Ml hospitalization in the hot season
    but not the cold season.
    December 2009
                                    E-129
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Zanobetti and Schwartz
    (2006, 0901951
    
    Period of Study: 1995-1999
    
    Location: Boston Metropolitan area
    Outcome (ICD-9): Myocardial infarction
    (410) or pneumonia (480-487)
    
    Age Groups: 65 + yr
    
    Study Design: Case-crossover
    
    N: 15,578 patients admitted for Ml and
    25,857 admitted for pneumonia
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature, day of the
    week.
    
    Season: All, and also assessed for
    interaction by hot (Apr-Sep) vs.. cold
    season
    
    Dose-response Investigated: No
    
    Statistical Package: SAS Software
    Release 8.2
    
    Lags Considered: Lag 0,  and mean of
    lags 0 -1
    Pollutant: BC
    
    Averaging Time: 24 h
    
    Median (ug/m3) (IQR 5th-95th
    percentiles):
    1.15(0.74-1.72
    
    0.42-2.83)
    
    Monitoring Stations: 1
    
    Copollutant (correlation):
    
    PM25:r = 0.66
    
    N02:r = 0.70
    
    CO: r = 0.82
    
    03:r =  -0.25
    
    PM non-traffic: r = -0.01
    PM Increment: Difference between the
    90th and 10th percentile for BC
    
    Myocardial infarction cohort (Lag 0):
    2.01 pg/m3
    
    Myocardial infarction cohort (Lag 0-1):
    1.69|jg/m3
    
    Pneumonia cohort (Lag 0): 2.05 pg/m3
    
    Pneumonia cohort (Lag 0 -1):
    1.69|jg/m3
    
    Percentage (%) increase in risk [95%
    Cl]:
    Myocardial infarction cohort:
    Lag 0:6.98 (-0.27-13.76)
    Lag 0-1: 8.34 (0.21-15.82)
    
    Pneumonia cohort:
    |Lag 0:10.76 (4.54-15.89)
    Lag 0-1:11.71 (4.79, 17.36)
    Notes: Assessed for effect modification
    by season. Results are reported in Fig
    2. Summary of results: PM2.BC is
    associated with pneumonia
    hospitalization in the cold season but
    not the hot season. BC had a stronger
    positive association with Ml
    hospitalization in the cold season, but
    the confidence interval was wide.
     All units expressed in pg/m unless otherwise specified.
    Table E-8.      Short-term exposure-cardiovascular-ED/HA-other size fractions.
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Andersen et al, (2008,
    1896511
    Period of Study: May 2001-Dec 2004
    
    Location: Copenhagen, Denmark
    Outcome (ICD-10): CVD, including
    angina pectoris (I20), myocardial
    infarction (121-22), other acute ischemic
    heart diseases (I24), chronic ischaemic
    heart disease (I25),  pulmonary
    embolism (I26), cardiac arrest (I46),
    cardiac arrhythmias (148-48), and heart
    failure (ISO).
    
    RD, including chronic bronchitis
    (J41-42), emphysema (J43), other
    chronic obstructive pulmonary disease
    (J44),  asthma  (J45), and status
    asthmaticus (J46).
    
    Pediatric hospital admissions for
    asthma (J45) and status asthmaticus
    (J46).
    
    Age Groups: >65 yr (CVD and RD),
    5-1 Syr (asthma)
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Poisson GAM
    
    Covariates: Temperature, dew-point
    temperature, long-term trend,
    seasonality, influenza, day of the week,
    public holidays, school holidays (only
    for 5-18 yr olds), pollen  (only for
    pediatric asthma outcome)
    
    Season: NR
    Pollutant: Total number concentration
    of ultrafme and accumulation mode
    particles (NCtot) (particles/cm3)
    
    Averaging Time: 24 h
    
    NCtotal
    Mean(SD): 8,116(3502)
    Median: 7,358
    IQR: 5,738-9,645
    99th Percentile:  19,895
    
    NCa12
    Mean (SD): 493 (315)
    Median: 463
    IQR: 308-650
    99th Percentile:  1,263
    
    NCa23
    Mean (SD): 2,253 (1,364)
    Median: 2,057
    IQR: 1,280-3,066
    99th Percentile:  6,096
    
    NCa67
    Mean (SD): 5,104 (2,687)
    Median: 4,562
    IQR: 3,248-6,274
    99th Percentile:  14,410
    
    NCalOO
    Mean (SD): 6,847 (2,846)
    Median: 6,243
    IQR: 4,959-8,218
    99th Percentile:  16,189
    
    NCa212
    PM Increment: IQR increase in
    pollutant level: Nctot: 3907 particles/cm
    (IQR)
    Ncai2:342 particles/cm3 (IQR)
    Nca23:1786 particles/cm* (IQR)
    Nca57:3026 particles/cm3 (IQR)
    NCIOO: 3259 particles/cm  (IQR)
    Nca2i2: 495 particles/cm3 (IQR)
    Relative risk (RR) Estimate [Cl]: CVD
    hospital admissions (4-day avg, lag 0 -
    3), age 65+
    
    One-pollutant model (NCtot):
    1.00 [0.99-1.02]
    Adj for PM,0: 0.98 [0.96-1.01]
    Adj for PM25: 0.99 [0.95-1.03]
    Adj for CO: 0.99 [0.97-1.02]
    Adj for N02:1.01 [0.98-1.03]
    Adj for 03:1.01 [0.96-1.06]
    One-pollutant model (NC100):
    1.00 [0.98-1.02]
    One pollutant model (Nca12):
    0.99 [.97-1.01]
    Adj for other size fractions:
    0.99 [0.97-1.02]
    One pollutant model (Nca23):
    0.99 [0.96-1.01]
    Adj for other size fractions:
    0.99 [0.96-1.02]
    One pollutant model (NCa57):
    1.01 [0.98-1.02]
    Adj for other size fractions:
    0.99 [0.97-1.02]
    One pollutant model (Nca212):
    1.02 [1.00-1.04]      	
    December 2009
                                    E-130
    

    -------
                  Study
    Design & Methods
    Concentrations!
    Effect Estimates (95% Cl)
                                         Dose-response Investigated: No
    
                                         Statistical Package: R statistical
                                         software (gam procedure, mgcv
                                         package)
    
                                         Lags Considered: Lag 0 -5 days, 4-
                                         day pollutant avg (lag 0 -3) for CVD, 5-
                                         day avg (lag 0-4) for RD, and a 6-day
                                         avg (lag 0-5) for asthma.
                                 Mean (SD): 392 (441)
                                 Median: 246
                                 IQR: 89-584
                                 99th Percentile: 2,248
                                 *NC, number concentration tot, total (all
                                 particles 6-700 in diameter) a12, size
                                 mode with mean diameter of 12 nm
                                 a23, size mode with median diameter of
                                 23 nm
                                 a57, size mode with median diameter of
                                 57 nm a212 size mode with median
                                 diameter of 212 nm
                                 NC100 = a12+a23+0.797*a57+0.084*a
                                 212.
                                 Monitoring Stations: 1
    
                                 Copollutant (correlation):
                                 Correlation of NCtot with:
                                 PM,o:r = 0.39
                                 PM25:r  = 0.40
                                 N02:r = 0.68
                                 :r = 0.66
                                 NCi00:r = 0.98
                                 NCa12:r = 0.31
                                 NCa23:r = 0.57
                                 NCa57:r = 0.87
                                 NCa212:r = 0.29
                                 CO: r =  0.54
                                 N0xcurbside:r = 0.36
                                 03:r = -0.12
    
                                 Other variables:
                                 Temperature:  r = -0.06
                                 Relative humidity:  r =  -0.04
                                Adj for other size fractions:
                                1.02 [1.00-1.05]
                                Adj for PM10: 0.98 [0.95-1.01]
                                RD hospital admissions (5-day avg, lag
                                0 -4), age 65+: One-pollutant model:
                                1.04 [1.00-1.07]
                                Adj for PM,0:1.00 [0.96-1.05]
                                Adj for PM25: 0.97 [0.89-1.05]
                                Adj for CO: 1.03 [0.98-1.07]
                                Adj for N02:1.00 [0.95-1.05]
                                Adj for 03: 0.95 [0.87-1.04]
                                One pollutant model (NC100):
                                1.03 [0.99-1.07]
                                One pollutant model (Nca12):
                                1.01 [0.98-1.05]
                                Adj for other size fractions:
                                1.01 [0.97-1.05]
                                One pollutant model (Nca23):
                                0.99 [0.94-1.03]
                                Adj for other size fractions:
                                0.98 [0.94-1.03]
                                One pollutant model (Nca57):
                                1.04 [1.00-1.08]
                                Adj for other size fractions:
                                1.02 [0.97-1.06]
                                One pollutant model (Nca212):
                                1.04 [1.01-1.08]
                                Adj for other size fractions:
                                 1.03 [0.99-1.07]
                                Adj for PM10:1.01 [0.96-1.07]
                                Asthma hospital admissions (6-day avg
                                lag 0-5), age 5-18: One-pollutant model:
                                1.07 [0.98-1.17]
                                Adj for PM10:1.03 [0.92-1.15]
                                Adj for PM25:1.04 [0.85-1.28]
                                Adj for CO: 1.09 [0.99-1.21]
                                Adj for N02:1.07 [0.96-1.19]
                                Adj for 03:1.08 [0.87-1.35]
                                One pollutant model (NC100):
                                1.06 [0.97-1.16]
                                One pollutant model (Nca212):
                                1.08 [0.99-1.18]
                                Adj for other size fractions:
                                1.07 [0.97-1.19]
                                One pollutant model (Nca23):
                                1.09 [0.98-1.21]
                                Adj for other size fractions:
                                1.08 [0.97-1.21]
                                One pollutant model (Nca57):
                                1.02 [0.94-1.12]
                                Adj for other size fractions:
                                0.93 [0.83-1.04]
                                One pollutant model (Nca212):
                                1.08 [1.00-1.17]
                                Adj for other size fractions: 1.12
                                [1.02-1.23]
                                Adj for PM10:1.10 [0.96-1.13]
                                Notes: Fig 2: Relative risks and 95%
                                confidence intervals per IQR in single
                                day concentration (0-5 day lag).
    
                                Summary of Fig 2: CVD: Positive,
                                marginally or statistically significant
                                associations at Lag 2 (Nctot, Nca57,
                                Nca212), Lag3 (Nca212), and Lag 1
                                (Nca212). RD: Positive, statistically or
                                marginally significant associations at
                                Lag 4 (Nctot, Nca57,  NCa212) and Lag
                                5 (Nctot, Nca57, Nca212), and to a
                                lesser extent Lag 2 (Nctot, Nca212) and
                                Lag 3 (Nctot, Nca212). Asthma: Wide
                                confidence intervals make interpretation
                                difficult. Positive, significant association
                                forNca212atLagl
    December 2009
                              E-131
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Lanki et al. (2006, 0897881
    
    Period of Study: 1992-2000
    
    Location: Augsburg, Barcelona,
    Helsinki, Rome, and Stockholm
    Outcome (ICD-9): Acute myocardial
    infarction (410
    
    ICD-10:I21, I22)
    
    Age Groups: 35+ yr, <75 yr, 75+ yr
    
    Study Design: Time series
    
    N: 26,854 hospitalizations
    
    Statistical Analyses: GAM
    
    Covariates: Temperature,  barometric
    pressure
    
    Season: V\ferm (Apr-Sep) and cold
    (Oct-Mar)
    
    Dose-response Investigated: No
    
    Statistical Package: R package mgcv
    0.9-5
    
    Lags Considered: 0-3 days
    Pollutant: UFP (PNC)
    
    Averaging Time: 24 h
    Median particles/cm3:
    Augsburg: 12,400
    Barcelona: 76,300
    Helsinki: 13,600
    Rome: 46,000
    Stockholm: 11,800
    Copollutant (correlation):
    Augsburg
    PM,o:r = 0.53
    CO: r = 0.63
    N02:r = 0.65
    03:r = 0.26
    
    Barcelona:
    PM,o:r = 0.38
    CO: r = 0.80
    N02:r = 0.49
    03:r = -0.35
    
    Helsinki:
    PM,0:r = 0.45
    CO: r = 0.48
    N02:r = 0.82
    03:r = 0.01
    
    Rome:
    PM,0:r = 0.32
    CO: r = 0.83
    N02:r = 0.68
    03:r = 0.03
    
    Stockholm:
    PMi0:r = 0.06
    CO: r = 0.56
    N02:r = 0.83
    03:r = -0.01
    PM Increment: 10,000 particles/cm
    
    Pooled Rate Ratio [Cl]: All 5 cities
    (35+ yr)
    Same-day lag: 1.005 [0.996,1.015]
    1-day lag: 0.997 [0.982,1.012
    2-day lag: 0.999 [0.990,1.008
    3-day lag: 0.998 [0.979,1.017]
    3 cities with hospital discharge register
    (35+ yr)
    Same-day lag: 1.013 [1.000,1.026]
    1-day lag: 0.995 [0.953,1.039
    2-day lag: 1.001 [0.989,1.014
    3-day lag: 1.009 [0.974,1.046]
    
    V\ferm season (35+ yr)
    Same-day lag: 1.009 [0.972,1.048]
                                                                                                                 1-day lag: 1.023
                                                                                                                 2-day lag: 1.050
                   0.988,1.060
                   1.016,1.085
                                                                                                                 3-day lag: 1.022 [0.987,1.C
    
                                                                                                                 Cold season (35+ yr)
                                                                                                                 Same-day lag: 1.014 [1.001,1.028]
                                                                                                                 1-day lag: 1.001 [0.956,1.048
                                                                                                                 2-day lag: 1.001 [0.989,1.014
                                                                                                                 3-day lag: 1.009 [0.971,1.049]
    
                                                                                                                 Age >75Non-fatal
                                                                                                                 Same-day lag: 1.032 [1.008,1.056]
                                                                                                                 1-day lag: 1.009 [0.985,1.032
                                                                                                                 2-day lag: 0.989 [0.966,1.013
                                                                                                                 3-day lag: 1.009 [0.969,1.051]
    
                                                                                                                 Fatal
                                                                                                                 Same-day lag: 1.016 [0.978,1.055]
                                                                                                                 1-day lag: 1.001 [0.966,1.038
                                                                                                                 2-day lag: 1.005 [0.969,1.041
                                                                                                                 3-day lag: 0.984 [0.948,1.021]
                                                                                                                 Notes: Rate ratios for PNC are given
                                                                                                                 for 0-5 lag days in graph form (Fig 1) for
                                                                                                                 each city. Pooled rate ratios were also
                                                                                                                 provided for groups <75 yielding similar
                                                                                                                 results to the overall 3-city data.
    Reference: Metzger et al. (2004,
    0442221
    
    Period of Study: Aug 1998-Aug 2000
    
    Location: Atlanta Metropolitan area
    (Georgia)
    Outcome (ICD-9): Emergency visits for
    ischemic heart disease (410-414),
    cardiac dysrhythmias (427), cardiac
    arrest (427.5), congestive heart failure
    (428), peripheral vascular and
    cerebrovascular disease (433-437, 440,
    443-444, 451-453), atherosclerosis
    (440), and stroke (436).
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 4,407,535 emergency department
    visits between 1993-2000 (data not
    reported for 1998-2000)
    
    Statistical Analyses:  Poisson
    generalized linear modeling
    
    Covariates: Day of the week, hospital
    entry and exit indicator variables,
    federally observed holidays, temporal
    trends, temperature, dew point
    temperature
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: SAS
    
    Lags Considered: 3-day ma, lags 0-7
    Pollutant: UFP (10-100 nm particle
    count) (no/cm3)
    
    Averaging Time: 24 h
    
    Median (10%-90% range): 25,900
    (11,500-74,600)
    
    Monitoring Stations: 1
    Copollutant (correlation):
    PM,0:r = -0.13
    03:r = -0.13
    N02:r = 0.26
    CO: r = 0.10
    S02:r = 0.24
    PM25:r = -0.16
    PM2 5 water soluble metals: r = -0.27
    PM25sulfates:r = -0.31;
    PM25 acidity: r = -0.39;
    PM25OC:r = 0.08;
    PM25EC:r = 0.08;
    PM25 oxygenated hydrocarbon: r = 0.05
    
    Other variables:
    Temperature: r = -0.33
    Dew point: r = -0.41
    PM Increment: 30,000 no/cm
    (approximately 1 SD)3
    
    RR [95% Cl]: For 3 day ma: All CVD:
    0.985 [0.965, 1.005]
    
    Dysrhythmia: 0.972 [0.937,1.008]
    
    Congestive heart failure: 0.983
    [0.943-1.025]
    
    Ischemic heart disease: 0.989
    [0.953-1.026]
    
    Peripheral vascular and
    cerebrovascular disease: 0.998
    [0.960-1.039]
    
    Results for Lags 0-7 expressed in
    figures (see notes).
    
    Notes: Fig 1: RR (95% Cl) for single-
    day lag models for the association of
    ER visits for CVD with daily ambient
    UFP.
    
    Summary of Fig  1 results: Null or
    negative associations.
    December 2009
                                     E-132
    

    -------
    Study
    Reference: von Klot et al. (2005,
    0880701
    Period of Study: 1992-2001
    Location:
    Augsburg, Germany
    Barcelona, Spain
    Helsinki, Finland
    
    Rome, Italy
    Stockholm, Sweden
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome (ICD-9): Acute myocardial
    infarction (410
    ICD-10: 121-122), angina pectoris (411,
    413
    
    ICD-1 0:120, 124), dysrhythmia (427
    ICD-10: 146.0, 46.9, I47-I49, ROD. 1,
    R00.8), heart failure (428
    ICD-10: 150)
    Age Groups: 35+ yr
    Study Design: Cohort
    
    N: 22,006 Ml survivors
    
    Statistical Analyses: GAM, Spearman
    correlation
    Covariates: Temperature, dew point
    temp, avg barometric pressure, relative
    humidity
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: R-software with
    "mgcv" package
    Lags Considered: 0-3 days
    
    
    
    
    
    
    
    
    
    
    Concentrations'!
    Pollutant: UFP (PNC)
    Averaging Time: 24 h
    Mean particle/cm3 (6th-96th
    percent! le):
    Augsburg:
    Barcelona:
    Helsinki:
    Rome:
    Stockholm:
    Monitoring Stations: NR
    Copollutant (correlation):
    Augsburg
    PM,0:r = 0.52
    CO: r = 0.63
    N02' r = 064
    03: r =-0.32
    Barcelona
    PM • r - n 9Q
    riviio. r - u.zy
    CO: r = 0.71;
    N02:r = 0.44
    03: r =-0.55
    
    Helsinki
    PM10' r = 046
    CO: r = 0.47;
    N02:r = 0.83
    03:r=-0.16
    Rome
    PM,0:r = 0.33
    CO: r = 0.80;
    N02:r = 0.71
    03: r =-0.47
    Stockholm
    PMi0:r = 0.06
    CO: r = 0.54;
    N02:r = 0.80
    03:r=-0.17
    Effect Estimates (95% Cl)
    PM Increment: 10,000 particles/cm3
    Pooled RR Estimate [Cl]:
    All cardiac admissions: 1.026
    [1.005,1.048]
    Myocardial infarction: 1.039
    [0.998.1.082]
    Angina pectoris: 1.020 [0.992,1.048]
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    All units expressed in pg/m  unless otherwise specified.
    December 2009
    E-133
    

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    E.2. Short-Term Exposure and Respiratory Outcomes
    
    
    
    E.2.1. Respiratory Morbidity Studies
    Table E-9.   Short-term exposure-respiratory morbidity outcomes -PMio.
    Study
    Reference: Aekplakorn, et al. (2003,
    0899081
    Period of Study: 107 days,
    from Oct1997-Jan 1998
    Location: Mae Mo district, Lampang
    Province, North Thailand
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Upper respiratory symptoms,
    lower respiratory symptoms, cough
    Age Groups: 6-1 4 yr old
    Study Design: Logistic regression
    N: 98 asthmatic school children, 98
    non-asthmatic school children
    Statistical Analyses: GEE, stratified
    analysis, PROCGENMOD
    Covariates: Temperature and relative
    humidity
    Season: Winter
    Dose-response Investigated? No
    Statistical Package: SASv 8.1
    
    
    
    
    
    
    
    
    
    Concentrations!
    Pollutant: PM,0
    Averaging Time: Daily
    Mean (SD):
    Sob Pad station: 31. 92
    Sob Mo station: 33.64
    Hua Fai station: 37.45
    Range (Min, Max):
    Sob Pad: 6.63, 153.25
    Sob Mo: 4.23, 121.80
    Hua Fai: 6.98, 113.30
    Monitoring Stations: 3
    Copollutant: PM25, S02
    
    
    
    
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    Odds Ratios [Lower Cl, Upper Cl]
    Ian1
    Asthmatics: URS: 1.03 (0.99, 1.07)
    lagO
    LRS: 1.04 (0.99, 1.09)
    lagO
    Cough: 1.04 (1.00, 1.07)
    lagO
    Non-Asthmatics: URS: 1.04 (0.99, 1.08)
    lagO
    LRS: 1.0 (0.93, 1.07)
    lagO
    Cough: 0.99 (0.94, 1.05)
    lagO
    PM10 + S02
    Asthmatics: URS: 1.03 (0.99, 1.07)
    lagO
    LRS: 1.03 (0.98, 1.09)
    lagO
    Cough: 1.04 (1.00, 1.08)
    lagO
    Non-Asthmatics: URS: 1.04 (0.99, 1.08)
    lagO
    LRS: 1.0 (0.93, 1.07)
    lagO
    Cough: 0.99 (0.95, 1.05)
    lagO
    December 2009
    E-134
    

    -------
                  Study
    Design & Methods
    Concentrations!
    Effect Estimates (95% Cl)
    Reference: Andersen et al. (2008,
    1896511
    Period of Study:
    Dec 1998-Dec 2004
    Location: Copenhagen, Denmark
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Daily symptoms (prospective
    daily recording of symptoms via diary)
    Age Groups: 0-3 yr
    Study Design: Panel study of children
    with genetic susceptibility to asthma
    (mothers had asthma)
    N: 205 children (living within a 15km
    radius of the central monitor during the
    first Syr of life)
    
    born between Aug 2, 1998 and Dec 12,
    2001
    
    Statistical Analyses: Logistic
    regression model (GEE)
    Covariates: Temperature, season,
    gender, age, exposure to smoking, and
    paternal history of asthma
    Effect modification: gender, medication
    use, and paternal history of asthma
    Statistical Package: SASv91
    Lag: 0,1, 2,3,4,2-4
    
    
    
    
    
    
    
    Pollutant: PM,0
    Mean: 25.1
    SD: 16.7
    Percentiles:
    25th: 15.7
    75th: 30.2
    IQR: 14.5
    
    Copollutant (correlation):
    PM25(r = 0.79)
    
    Number concentration of ultrafine
    particles,
    UFP(r = 0.37)
    N02(r = 0.43)
    N0x(r = 0.40)
    CO (r = 0.45)
    
    03 (r = -0.32)
    Temp (r = 0.25)
    
    
    
    
    
    
    
    PM Increment: IQR (14.5 pg/m3)
    increase
    
    Odds Ratios (95%CI) for incident
    wheezing symptoms
    Age 0-1
    10:1.05(0.88,1.25)
    11:1.00(0.82,1.22)
    L2:1.01 (0.83, 1
    13:1.20(0.98,1
    L4: 1.23(1.02, 1
    L2-4: 1.21 (0.99,
    
    Age 1-2
    LO' 1 00 (0 86 1
    L1 : 1.02 (0.8?! 1
    12:1.05(0.93,1
    L3: 0.96 (0.84, 1
    14:1.04(0.90,1
    12-4:1.03(0.88,
    Age 2-3
    LO: 0.87 (0.72, 1
    L1: 0.95 (0.78, 1
    L2: 0.99 (0.82, 1
    L3: 1.03(0.84,1
    L4: 0.89 (0.74, 1
    L2-4: 0.94 (0.74,
    Age 0-3
    LO: 0.97 (0.87, 1
    L1: 0.99(0.89,1
    L2: 1.01(0.92,1
    L3: 1.03 (0.93, 1
    L4: 1.04 (0.94, 1
    L2-4: 1.04 (0.92,
    23
    46
    48)
    1.48)
    
    
    15
    19
    19)
    09
    21
    1.22)
    
    06)
    15
    17
    25)
    09)
    1.19)
    
    08
    10
    12)
    14
    15
    1.17)
                                                                                                               Two pollutant models (lag 2-4)
    
                                                                                                               1-pollutant model: 1.21 (0.99,1.48)
    
                                                                                                               2-pollutant (adj for N02): 1.13 (0.88,
                                                                                                               1.45)
    
                                                                                                               2-pollutant (adj for): 1.16 (0.90,1.48)
    
                                                                                                               2-pollutant (adj for CO): 1.23 (0.96,
                                                                                                               1.57)
    
                                                                                                               110 children living within 5km radius
                                                                                                               from monitor (sensitivity analysis): Age
                                                                                                               0-1:1.32(0.95,1.82)
                                                                                                               Age 1-2:1.20 (0.87, 1.67)
                                                                                                               Age 2-3: 0.78 (0.52, 1.16)
                                                                                                               Age 0-3:1.11 (0.88,1.39)	
    December 2009
                             E-135
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Boezen et al. (2005,
    0873961
    
    Period of Study: Two consecutive
    winters (winter 1993-winter 1995)
    
    Location: Rural (Meppel, Nunspeet)
    and urban (Amsterdam) areas in the
    Netherlands
    Outcome: FEVi, airway
    hyperresponsiveness (AHR), serum
    total IgE and daily data on lower
    respiratory symptoms (LRS), upper
    respiratory symptoms (URS), cough
    and morning and evening peak
    expiratory flow
    
    Age Groups: 50-70 yr
    
    Study Design: Case-control study
    
    N: 327 patients
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: daily minimum
    temperature, linear, quadratic and cubic
    time trend, weekend/holidays, and
    influenza incidence for the rural and
    urban areas and two winters separately
    
    Season: winter
    
    Dose-response Investigated? No
    
    Lags Considered: 0,1, 2, and 5-day
    mean
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD):
    Winter 93/94 Urban: 41.5
    Winter 93/94 Rural: 44.1
    Wnter 94/95 Urban: 31.1
    Wnter 94/95 Rural: 26.6
    Percentiles: SOth(Median):
    Wnter 93/94 Urban: 34.6
    Wnter 93/94 Rural: 30.4
    Wnter 94/95 Urban: 28.9
    Wnter 94/95 Rural: 23.7
    Range (Min, Max):
    93/94 Urban: (12.1-112.7)
    93/94 Rural: (7.9-242.2)
    94/95 Urban: (8.8-89.9)
    94/95 Rural: (7.1-96.9)
    Copollutant:
    S02
    N02
    BS
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    AHFWIgE-
    Upper Respiratory Symptoms
    Lag 0: OR = 0.99 (0.97-1.01)
    Lag 1: OR = 1.01 (0.99-1.03)
    Lag 2: OR = 1.00 (0.96-1.02)
    5-day mean: OR = 1.00 (0.96-1.04)
    Cough
    Lag 0: OR = 1.00 (0.99-1.02)
    Lag 1: OR = 0.99 (0.98-1.01)
    Lag 2: OR = 1.00 (0.98-1.01)
    5-day mean: OR = 0.98 (0.95-1.01)
    >10% fall in morning peak expiratory
    flow
    Lag 1: OR = 1.01 (0.98-1.04)
    Lag 2: OR = 0.97 (0.94-1.00)
    5-day mean: OR = 0.97 (0.92-1.02)
    AHR-/lgE+
    Upper Respiratory Symptoms
    Lag 0: OR = 1.01 (0.99-1.03)
    Lag 1: OR = 1.02 (1.00-1.04)
    Lag 2: OR = 1.01 (0.99-1.03)
    5-day mean: OR = 1.08 (1.04-1.11)
    Cough
    Lag 0: OR = 1.01 (0.99-1.03)
    Lag 1: OR = 0.99 (0.98-1.01)
    Lag 2: OR = 1.00 (0.98-1.02)
    5-day mean: OR = 1.01 (0.97-1.05)
    >10% fall in morning peak expiratory
    flow
    Lag 1: OR = 0.99 (0.97-1.02)
    Lag 2: OR = 0.99 (0.97-1.02)
    5-day mean: OR = 0.97 (0.93-1.01)
    AHR+/lgE-
    Upper Respiratory Symptoms
    Lag 0: OR = 0.99 (0.95-1.03)
    Lag 1: OR = 1.01 (0.97-1.05)
    Lag 2: OR = 0.99 (0.96-1.03)
    5-day mean: OR = 0.98 (0.91-1.06)
    Cough
    Lag 0: OR = 1.00 (0.97-1.02)
    Lag 1: OR = 1.01 (0.98-1.03)
    Lag 2: OR = 0.99 (0.96-1.02)
    5-day mean: OR = 1.02 (0.96-1.08)
    >10% fall in morning peak expiratory
    flow
    Lag 1: OR = 0.99 (0.95-1.03)
    Lag 2: OR = 0.99 (0.95-1.03)
    5-day mean: OR = 0.99 (0.93-1.06)
    AHR+/lgE+
    Upper Respiratory Symptoms
    Lag 0: OR = 1.01 (0.98-1.04)
    Lag 1: OR = 1.03 (1.00-1.05)
    Lag 2: OR = 1.02 (0.99-1.05)
    5-day mean: OR = 1.06 (1.00-1.11)
    Cough
    Lag 0: OR = 1.03 (1.01-1.06)
    Lag 1: OR = 1.00 (0.98-1.02)
    Lag 2: OR = 0.99 (0.97-1.01)
    5-day mean: OR = 0.99 (0.95-1.04)
    Lag 2: OR = 0.99 (0.96-1.03)
    5-day mean: OR = 0.99 (0.92-1.05)
    >10% fall in morning peak expiratory
    flow
    Lag 1: OR = 1.04 (1.00-1.07)
    Lag 2: OR = 1.03 (0.99-1.06)
    5-day mean: OR = 1.05 (0.99-1.11)
    Reference: Boezen et al. (1999,
    0404101
    
    Periods of Study:
    3 Wnters (1992-1995)
    
    Location: Urban and rural areas of the
    Netherlands
    Outcome: Respiratory symptoms
    
    Lower respiratory symptoms (wheeze,
    attacks of wheezing, shortness of
    breath)
    
    Upper respiratory symptoms (sore
    throat, runny or blocked nose)
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Wnter 1992-93
    Urban: 54.8
    Rural: 44.7
    Wnter 1993-94
    Increment: 100|jg/m
    
    Odds Ratio (Lower Cl, Upper Cl) lag:
    OR for respiratory symptoms and
    exposure to PMio in children with BHR
    and high serum total IgE
    Lower Respiratory Symptoms
    1.32(1.07,1.63)0   	
    December 2009
                                    E-136
    

    -------
                  Study
    Design & Methods
    Concentrations!
    Effect Estimates (95% Cl)
                                       Bronchial hyperresponsiveness (BHR)
    
                                       Study Design: Time-series
    
                                       Statistical Analyses: Logistic
                                       regression (PROC model)
    
                                       Age Groups: 7-11
                                Urban: 41.5 3
                                Rural: 44.1
                                Winter 1994-95
                                Urban: 31.1
                                Rural: 26.6
    
                                Range (Min, Max):
                                Winter 1992-93
                                Urban: (4.7,145.6)
                                Rural: (4.8,103.8)
                                Wnter 1993-94
                                Urban: (12.1,112.7)
                                Rural: (7.9, 242.2)
                                Wnter 1994-95
                                Urban: (8.8, 89.9)
                                Rural: (7.1, 96.9)
    
                                Co pollutants:
                                BS
                                S02
                                N02
                               1.36(1.13, 1.64) 1
                               1.36(1.13, 1.65)2
                               2.39 (1.71, 3.35) 0-5 avg.
                               Upper Respiratory Symptoms
                               1.13(0.97,1.32)0
                               1.00(0.87,1.16)1
                               0.96(0.84,1.11)2
                               0.91 (0.70, 1.18) 0-5 avg
                               >10% morning peak expiratory flow
                               (PEF) decrease
                               1.10(0.92,1.33)0
                               1.08(0.90,1.28)1
                               1.03(0.87,1.23)2
                               1.10(0.83, 1.46) 0-5 avg
                               >10% evening peak expiratory flow
                               (PEF) increase
                               1.37(1.16, 1.63)0
                               1.09(0.92,1.29)1
                               1.16(0.98.1.36)2
                               1.35(1.04, 1.77) 0-5 avg.
                               OR for respiratory symptoms and
                               exposure to PMi0 in children without
                               BHR and low serum total IgE
                               Lower Respiratory Symptoms
                               1.08(0.75,1.57)0
                               1.04(0.70, 1.53)1
                               0.98(0.69,1.39)2
                               1.15 (0.61, 2.15) 0-5 avg.
                               Upper Respiratory Symptoms
                               1.12(0.99,1.28)0
                               1.01(0.89,1.15)1
                               1.01 (0.89, 1.15)2
                               0.93(0.67, 1.28) 0-5 avg
                               >10% morning PEF decrease
                               1.07(0.93, 1.23)0
                               0.86 (0.75, 0.99) 1
                               0.97(0.85,1.11)2
                               0.99(0.79, 1.23) 0-5 avg
                               >10% evening PEF decrease
                               1.13(0.98,1.30)0
                               1.05(0.91, 1.21)1
                               0.99(0.87,1.14)2
                               0.94(0.75, 1.17) 0-5 avg
                               OR for respiratory symptoms and
                               exposure to PM10 in children with BHR
                               and low serum total IgE
                               Lower Respiratory Symptoms
                               0.77(0.48,1.24)0
                               1.34(0.94,1.93)1
                               1.24(0.86, 1.81)2
                               1.92(0.84, 4.41) 0-5 avg
                               Upper Respiratory Symptoms
                               1.13(0.92, 1.40)0
                               0.98(0.79,1.22)1
                               0.97(0.79,1.20)2
                               0.83(0.54, 1.25) 0-5 avg
                               >10% morning PEF decrease
                               1.04(0.78,1.38)0
                               0.86(0.66, 1.12)1
                               0.91(0.71,1.17)2
                               0.78(0.51, 1.20) 0-5 avg
                               >10% evening PEF decrease
                               1.07(0.82,1.41)0
                               0.98(0.76,1.26)1
                               0.93(0.73, 1.19)2
                               0.83(0.55, 1.26) 0-5 avg
                               OR for respiratory symptoms and
                               exposure to PMi0 in children without
                               BHR and high serum total IgE
                               Lower Respiratory Symptoms
                               1.04(0.80,1.35)0
                               1.21(0.98,1.51)1
                               1.18(0.96,1.45)2
                               1.35(0.89, 2.04) 0-5 avg
                               Upper Respiratory Symptoms
                               1.01(0.85,1.20)0
                               0.95(0.81, 1.12)1
                               0.93(0.80,1.09)2	
    December 2009
                            E-137
    

    -------
                  Study
                                                Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
                                                                                                                 0.93(0.69, 1.25) 0-5 avg
                                                                                                                 >10% morning PEF decrease
                                                                                                                 0.97(0.80,1.17)0
                                                                                                                 1.09(0.91,1.30)1
                                                                                                                 1.02(0.85, 1.21)2
                                                                                                                 0.95(0.71, 1.28) 0-5 avg
                                                                                                                 >10% evening PEF decrease
                                                                                                                 1.02(0.85, 1.22)0
                                                                                                                 1.06(0.90,1.25)1
                                                                                                                 1.08(0.93,1.27)2
                                                                                                                 1.04(0.80, 1.34) 0-5 avg.
    Reference: Chattopadhyay et al. (2007,  Outcome: pulmonary function tests
                                        (respiratory impairments)
    147471
    
    Period of Study: NR
    
    Location: Three different points in
    Kolkata, India: North, South, and
    Central
                                        Age Groups: All ages
    
                                        Study Design: Cross-sectional
    
                                        N: 505 people studied for PFT
    
                                        total population of Kolkata not given
    
                                        Statistical Analyses: Frequencies
    
                                        Covariates: Meteorologic data (i.e.
                                        temperature, wind direction, wind
                                        speed, and humidity)
    
                                        Dose-response Investigated? No
    Pollutant: PM,0
    
    Averaging Time: 8 h
    
    Mean (SD):
    
    North Kolkata: 535.9
    
    Central Kolkata: 1114.5
    
    South Kolkata: 909.2
    
    Monitoring Stations: 1
    
    Copollutant:
    
    PM<10-3.3
    
    PM<3.3-0.4
    PM Increment: NR
    
    Respiratory impairments (SD):
    North Kolkata
    Male (n = 137)
    Restrictive: 4 (2.92)
    Obstructive: 5 (3.64)
    Combined Res. And Obs.: 6 (4.37)
    Total: 15 (10.95)
    Female (n = 152)
    Restrictive: 3 (1.97)
    Obstructive: 5 (3.28)
    Combined Res. And Obs.: N/A
    Total: 8 (5.26)
    Total (n = 289)
    Restrictive: 7 (2.42)
    Obstructive: 10 (3.46)
    Combined Res. And Obs: 6 (2.07)
    Total: 23 (7.96)
    
    Central Kolkata
    Male (n = 44)
    Restrictive: 6 (13.63)
    Obstructive: 1 (2.27)
    Combined Res. And Obs.:1 (2.27)
    Total: 8 (18.18)
    Female (n = 50)
    Restrictive: 3 (6.00)
    Obstructive: 2 (4.00)
    Combined Res. And Obs.: N/A
    Total: 5 (10.00)
    Total (n = 94)
    Restrictive: 9 (9.57)
    Obstructive: 3 (3.19)
    Combined Res. And Obs.: 1 (1.06)
    Total: 13 (13.82)
    
    South Kolkata
    Male (n = 52)
    Restrictive:! (1.92)
    Obstructive: 2 (3.84)
    Combined Res. And Obs.: 3 (5.76)
    Total: 6 (11.53)
    Female (n = 70)
    Restrictive: 2 (2.85)
    Obstructive:! (1.42)
    Combined Res. And Obs.: N/A
    Total: 3 (4.28)
    Total (n = 122)
    Restrictive: 3 (2.45)
    Obstructive: 3 (2.45)
    Combined Res. And Obs.: 3 (2.45)
    Total: 9 (7.37)    	
    December 2009
                                                                         E-138
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Dales et al. (2006, 0907441
    
    Period of Study: Jan 1986-Dec 2000
    
    Location: 11 Canadian Cities: Calgary,
    Edmonton, Halifax, London, Hamilton,
    Ottawa, St. John, Toronto, Vancouver,
    Windsor, Winnipeg
    Health Outcome: Respiratory Illness:
    Asphyxia (799)
    
    Respiratory failure (799.1)
    
    Dyspnea and respiratory abnormalities
    (786)
    
    Respiratory distress syndrome (769)
    
    Unspecified birth asphyxia in live-born
    infant (768.9)
    
    Other respiratory problems after birth
    (770.8)
    
    Pneumonia (486)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    
    Age Groups: 0-27 days
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Copollutants (correlation):
    03:r =-0.29 to 0.41
    N02:r =-0.26 to 0.69
    S02:r =-0.09 to 0.61
    CO: r = -0.13 to 0.71
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) Lag:
    
    In respiratory illness and exposure to
    PMio in neonates
    
    PM10 alone: 2.13 (-0.50, 4.76)
    Multipollutant model
    PM10:1.45 (-1.90, 4.80)
    PM,o, 03: 2.67 (0.98, 4.39)
    PM,o, N02: 2.48 (1.18, 3.80)
    PM10, S02:1.41 (0.35,2.47)
    PM,o, 00:1.30(0.13, 2.49)
    Reference: de Hartog et al. (2003,
    0010611
    Period of Study: Wnter of 1998-1999
    
    Amsterdam, from Nov 1998 to Jun 1999
    
    Erfurt, from Oct 1998 to Apr 1999
    
    Helsinki, from Nov 1998 to Apr 1999
    
    Location:
    Amsterdam, the Netherlands;
    Erfurt, Germany; Helsinki, Finland
    Outcome: Respiratory symptoms
    
    Age Groups: > 50 yr
    
    Study Design: Panel
    
    N: 131 subjects with history of coronary
    heart disease
    
    Statistical Analyses:  Logistic
    regression
    
    Covariates: Ambient temperature,
    relative humidity, atmospheric pressure,
    incidence of influenza-like illness
    
    Season: Wnter
    
    Dose-response Investigated? No
    
    Statistical Package: S-PLUS 2000
    
    Lags Considered: 0-, 1-, 2-,  3-, and
    5-day avg
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Mean (SD):
    Amsterdam: 36.5
    Erfurt: 27.1
    Helsinki: 19.6
    
    Range (Min, Max):
    Amsterdam: (13.6-112.0)
    Erfurt: (5.2-104.2)
    Helsinki: (6.4-67.4)
    
    Monitoring Stations: 1
    
    Copollutant:
    PM25
    NCO.01-0.1
    CO
    N02
    S02
    There was a tendency toward positive
    associations between avoidance of
    activities and both particulate air
    pollution (PMio) and gases, but none of
    the associations were statistically
    significant....In both incidence analyses
    and prevalence analyses, odds ratios
    for PMio were generally similar to the
    corresponding odds ratios for PM25, but
    were somewhat less significant.'
    Reference: Delfmo et al. (1998,
    0514061
    Period of Study :Aug-Oct 1995
    
    Location: Alpine, CA
    Outcome: asthma symptom severity
    
    Age Groups: 9-17
    
    Study Design: Panel Study
    
    N: 24 non-smoking pediatric asthmatics
    
    Statistical Analyses: GEE
    
    Covariates: Day of week, temperature,
    humidity, wind speed
    
    Statistical Package: SAS
    
    Lags Considered: 0-5, 0, 0-4
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD):
    
    31(8)
    
    90th: 42
    
    Range (Min, Max):  16, 54
    
    Copollutant (correlation):
    
    03(r = 0.32)
    PM Increment: 42 pg/m3 (90th
    percentile increase)
    Asthma symptoms:
    Everyone: 1.47 (0.90, 2.39) lag 0
    Everyone: 1.73 (1.03, 2.89) lag 0-4
    Less symptomatic: 2.47 (1.23-4.95)
    lagO
    Less symptomatic: 4.03 (1.22,13.33)
    lag 0-4
    More symptomatic: 1.50  (0.80, 2.80)
    lagO
    More symptomatic: 1.95  (1.12, 3.43)
    lag 0-4
    PMio + 03
    Asthma symptoms: 1.31  (0.84, 2.06)
    lagO
    1.65(1.03, 2.66) lag 0-4
    Less symptomatic: 2.08 (1.12-3.83)
    lagO
    Less symptomatic: 3.35 (1.06,10.51)
    lag 0-4
    More symptomatic: 1.40  (0.77, 2.53)
    lagO
    More symptomatic: 1.87(1.11,3.13)
    lag 0-4	
    December 2009
                                    E-139
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Delfino et al. (2002,
    0937401
    
    Period of Study: Mar-Apr 1996
    
    Location: Alpine, California
    (a semi-rural area)
    Outcome: Asthma symptoms that
    interfere with daily activities
    
    Age Groups: 9-19 yr
    
    Study Design: Daily panel study
    
    N: 22 asthmatic children
    
    Statistical Analyses: GEE
    
    Covariates: Temperature, relative
    humidity, day-of-weektrends, linear
    time trend across the 61 days, and
    upper or lower respiratory infection
    
    Season: "Early spring season" of
    Mar-Apr
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS, version 8
    
    Lags Considered: 0-, 1-, 2-, 3-, 4-, 5-,
    and 3-day ma
     Pollutant: PM10
    Averaging Time: 1 h max
    Mean (SD): 38(15)
    Percentiles: 90th: 63
    Range (Min, Max): (12-69)
    Averaging Time: 8 h max
    Mean (SD): 28(12)
    Percentiles: 90th: 46
    Range (Min, Max): (8-57)
    Averaging Time: 24 h
    Mean (SD): 20(9)
    Percentiles: 90th: 32
    Range (Min, Max): (7-42)
    Copollutant (correlation):
    1 h maxPM10
    8h maxPM10: r = 0.93
    24hPM,o:r = 0.84
    1 h max 03:r = 0.68
    8h max03: r = 0.95
    1 h max N02:r = 0.49
    8hmaxN02:r = 0.55
    8 h max PM10:1 h max PM10: r = 0.93
    24hPM,0:r = 0.95
    1 h max 03:r = 0.72
    8h max03: r = 0.65
    1 h maxN02: r = 0.48
    8hmaxN02:r = 0.55
    24hPM10:1 h max PM10:r = 0.84
    8h maxPM10: r = 0.95
    1 h max 03:r = 0.74
    8h max03: r = 0.71
    1 h max N02:r = 0.37
    8hmaxN02:r = 0.44
    PM Increment: 90th percentile
    increase
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    ORs for risk of asthma symptoms in
    those who report a respiratory infection
    compared to those who do not have a
    respiratory infection
    1h max PM10 lag 0:4.88 (1.31-18.2)
    8 h max PM,o lag 0:6.78 (1.38-33.3)
    24 h mean PM10 lag 0: 4.68 (0.71-30.7)
    3-day ma 1 h max PM10:11.1 (1.10-112)
    3-dayma8hmaxPM10:10.1 (1.42-
    72.0)
    3-day ma 24 h PM,0: 2.67 (0.60-11.8)
    
    Effect modification by anti-inflammatory
    medication use on the relationship of
    asthma symptoms in children
    1 h max PM10 lag 0:1.41 (0.87-2.30)
    On medication: 0.96 (0.25-3.69)
    Not on medication: 1.92 (1.22-3.02)
    
    8 h max PM10 lag 0:1.19 (0.74-1.94)
    On medication: 0.75 (0.18-3.04)
    Not on medication: 1.68 (0.91-3.09)
    
    24 h mean PM,o lag 0:1.08 (0.73-1.61)
    On medication: 0.80 (0.24-2.69)
    Not on medication: 1.35 (0.82-2.22)
    
    3-day ma 1 h max PM10:1.45 (0.76-
    2.76)
    On medication: 1.01  (0.14-7.02)
    Not on medication: 1.92 (0.99-3.71)
    
    3-dayma8hmaxPM10:1.32(0.76-
    2.29)
    On medication: 0.82 (0.17-3.94)
    Not on medication: 1.89 (1.10-3.24)
    
    3-day ma 24 h PM,0:1.22 (0.84-1.77)
    On medication: 0.75 (0.26-2.14)
    Not on medication: 1.75 (1.15-2.68)
    
    Dose-response results are found in Fig
    2 and not quantitatively reported
    elsewhere.
    Reference: Delfino et al. (2003,
    0909411
    
    Period of Study: Nov 1999-Jan 2000
    
    Location:
    Huntington Park, Los Angeles
    Outcome: Asthma severity scale
    
    Peak Expiratory Flow Rate (PEF)
    
    Age Groups: Ages 10 to 16
    
    Study Design: Longitudinal study panel
    
    N: 22 children
    
    Statistical Analyses: Regression
    analysis (GEE, GLM)
    
    multivariate regression models
    
    Covariates: Day of the week, Maximum
    Temperature, Respiratory Infections
    
    Season: Winter
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 0,1
    Pollutant: PM,0
    
    Mean (SD): 59.9 (24.7)
    
    Range (Min, Max): 20-126
    
    IQR: 37
    
    90th: 86.0
    
    Monitoring Stations: 1
    
    Copollutant (correlation):
    
    8-h max N02 = 0.38
    
    8-hmax03 = -0.16
    
    8-h max CO = 0.50
    
    8-h max S02 = 0.73
    PM Increment: IQR 37.0 pg/m
    
    OR Estimate [Lower Cl, Upper Cl]
    
    lag:
    
    LagO
    
    Symptom Scores >1:1.45(1.11,1.90)
    
    Symptom Scores >2: NR
    
    Lag1
    
    Symptom Scores >1:1.07 (0.64,1.77)
    
    Symptom Scores >2: NR
    December 2009
                                   E-140
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Delfino et al. (2004,
    0568971
    
    Period of Study :Sep-Oct 1999
    
    Apr-Jun 2000
    
    Location: Alpine, California
    Outcome: FEVi
    
    Age Groups: 9-19 yr old
    
    Study Design: Panel study
    
    N: 24 children
    
    Statistical Analyses: GLM
    
    Akaike's information criterion and
    Bayesian information criterion
    
    Covariates: Day of week,  Personal
    temperature and relative humidity, time
    of FEVi maneuver (morning, afternoon,
    or evening),  Season (fall 1999 or spring
    2000)
    
    As-needed medication use
    
    Presence or absence of upper or lower
    respiratory infections
    
    Season: Spring,  Fall
    
    Dose-response  Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: Lag 0-4
    Pollutant: PM,0
    Averaging Time: 4 h, 8 h, 12 h, 24 h
    Personal Monitor
    1-h max personal PM last
    24-h
    Mean (SD): 151.0 (12.03)
    90th: 292.4
    Range (Min, Max): (9.1,996.8)
    Mean personal PM last 24-h
    Mean (SD): 37.9 (19.9)
    90th: 65.1
    Range (Min, Max):
    (3.9,  113.8)
    Central outdoor stationary-site PM
    1-h Maximum TEOM
    PM,o last 24-h
    Mean (SD): 54.4  (13.8)
    90th: 71.0
    Range (Min, Max): (24.4, 95.4)
    Mean TEOM PM,o last 24-h
    Mean (SD): 29.7  (8.6)
    90th: 40.9
    Range (Min, Max): (12.9, 50.7)
    24-h  mean PM10
    Mean (SD): 23.6  (9.1)
    90th: 34.6
    Range (Min, Max): (3.2, 48.0)
    Copollutant (correlation): 8-h max
    personal PM
    8-h max 03 = 0.03
    8-h Max N02 = 0.26
    24-h  Mean Personal
    PM = 0.94
    8-h Max TEOM PM,o = 0.38
    24-h  Mean TEOM PM10 = 0.40
    24-h  Central HI PM,o = 0.37
    24-h  Central HI PM25 = 0.38
    24-h  Outdoor HI PM,o = 0.32
    24-h  Outdoor HI PM2 5 = 0.39
    24-h  Indoor HI PM10 = 0.23
    24-h  Indoor HI PM25 = 0.37
    24-h  mean personal PM
    8-h max 03 = 0.01
    8-h Max N02 = 0.27
    8-h Max Personal PM = 0.94
    8-h Max TEOM PM10 = 0.36
    24-h  Mean TEOM PM10 = 0.39
    24-h  Central HI PM,o = 0.36
    24-h  Central HI PM25 = 0.43
    24-h  Outdoor HI PM,o = 0.34
    24-h  Outdoor HI PM2 5 = 0.44
    24-h  Indoor HI PM10 = 0.29
    24-h  Indoor HI PM25 = 0.46
    24-h  Mean TEOM PM,o
    8-h max 03 = 0.41
    8-h Max N02 = 0.58
    8-h Max Personal PM = 0.40
    24-h  Mean Personal PM = 0.39
    8-h Max TEOM PM10 = 0.92
    24-h  Central HI PM,o = 0.86
    24-h  Central HI PM25 = 0.78
    24-h  Outdoor HI PM,o = 0.79
    24-h  Outdoor HI PM2 5 = 0.78
    24-h  Indoor HI PM10 = 0.36
    24-h  Indoor HI PM25 = 0.59	
    Results presented graphically: Percent
    predicted FEV, was inversely
    associated with personal exposure to
    fine particles.
    
    - Inverse associations of FEV, with
    stationary-site indoor, outdoor and
    central-site gravimetric PM25 and PM10,
    and with hourly TEOM PM,o
    December 2009
                                   E-141
    

    -------
    Study
    Reference: Delfino et al. (2006,
    0907451
    Period of Study: Region 1 : Aug to Mid
    Dec 2003. Region 2: Jul through Nov
    2004
    Design & Methods
    Outcome: Fractional Concentration of
    Nitric Oxide in exhaled air (FENO)
    Age Groups: 9 through 18
    Study Design: Longitudinal Panel
    Study
    Concentrations!
    Pollutant: PM,0
    Central Site
    Averaging Time: 24 h
    Riverside
    Effect Estimates (95% Cl)
    PM Increment: IQR increase
    (Riverside: 28.41 pg/m3, Whittier
    21.87|jg/m3)
    Coefficient [Lower Cl, Upper Cl]
    lag: Lag = 2-day ma
    Location: Region 1: Riverside, CA.
    Region 2: Whittier, CA
    N: 45 children
    Statistical Analyses: Linear mixed-
    effects models
    Two-stage hierarchical model
    Empirical Variograms
    Fourth-order polynomial distributed lag
    mixed-effects model
    Covariates: Personal temperature,
    Personal Rel. Humid., 10-day exposure
    run, Respiratory infections, Region of
    study, Sex, Cumulative daily use of as-
    needed B-agonist inhalers
    Dose-response Investigated? No
    Lags Considered:  Lag 0, Lag  1, 2-day
    ma
    Mean (SD): 70.82 (29.36)
    SOth(Median): 65.96
    Range (Min, Max): (30.75,54.05) pg/m3
    Whittier
    Mean (SD): 35.73 (16.6)
    SOth(Median): 34.65
    Range (Min, Max):
    (5.86, 105.46) pg/m3
    Monitoring Stations: 48 personal
    nephelometers, 2 central  sites
    Stratified by Medication Use
    Not Taking Anti-lnflamm. Medication
    Central 0.76 (-1.54, 3.07)
    Taking Anti-lnflamm. Medication
    Central 0.53 (-0.83,1.90)
    Inhaled Corticosteroids
    Central 1.28 (-0.01, 2.58)
    Antileukotrienes +- inhaled
    corticosteroids
    Central-2.10 (-5.33,1.12)
    Notes: Fig of Estimated lag effect of
    hourly personal PM25 on FENO.
    Fig of the Estimated lag effect of hourly
    personal PM25 on FENO by use of
    medications.
    Fig of one- and two-pollutant models for
    change in FENO using 2-day Ma
    personal and central-site pollutant
    measurements.
    December 2009
                                     E-142
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Desqueyroux et al. (2002,
    0260521
    
    Period of Study: Nov 1995-Nov 1996
    
    Location: Paris, France
    Outcome: Asthma attacks
    
    Age Groups: Adults.
    
    Study Design: Panel study
    
    N: 60 moderate to severe adult
    asthmatics
    
    Statistical Analyses: Marginal logistic
    regression
    
    Covariates: FEV,, smoking, allergy,
    oral steroid treatment, mean daily
    temperature,  relative humidity, pollen
    counts, season, holiday period
    
    Season: winter, summer
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 1,2, 3, 4, 5, 3-5
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD):
    
    Summer: 23 (9)
    
    Winter: 28 (14)
    
    Range (Min, Max):
    
    Summer: 6, 63
    
    Winter: 9, 84
    
    Monitoring Stations: 7
    
    Copollutant: S02, N02, 03
    0.93
    1.11
    1.17
    1.16
    1.21
    0.80, 1.08
    0.98, 1.26
    1.03, 1.33
    1.01, 1.34
    1.01, 1.34'
    PM Increment: 10 pg/m
    
    OR Estimate [Lower Cl, Upper Cl]
      g: 0.87 [0.71,1.06] lag 1
              •"  lag 2
                   Iag3
                   lag 4
                   Iag5
                   lag 3-5
    
    Vs seasons alone:
    Winter: 1.41 [1.16,1.71] lag 3-5
    Summer: 1.03 [0.72,1.47] lag 3-5
    
    Vs link to explanatory factors:
    No link: [1.71 [1.20, 2.43] lag 3-5
    Link: 1.27 [1.06,1.52] lag 3-5
    
    Vs occurrence of infection:
    Wthout infection:
    1.52 [1.16, 2.00] lag 3-5
    Wth infection: 1.30 [1.03,1.65] lag 3-5
    
    Vs baseline pulmonary function:
    FEV,>/ = 68% predicted:
    1.38 [1.06, 1.79] lag 3-5
    FEV <68% predicted:
    1.45 [1.11, 1.90]  lag 3-5
    
    Vs smoking habits:
    Nonsmokers: 1.53 [1.18,1.98] lag 3-5
    Current & ex-smokers:
    1.18 [0.90, 1.54] lag 3-5
    
    Vs allergy:
    Non-allergic: 1.29 [0.94,1.77] lag 3-5
    Allergic:  1.49 [1.17,1.90] lag 3-5
    
    Vs regular oral steroid treatment:
    No: 1.41 [1.15,1.73] lag 3-5
    Yes: 1.41 [0.88, 2.25] lag 3-5
    
    Multipollutant model: PM,0 + N02:1.43
    [1.16, 1.76] Lag 3-5
    PMio + S02:1.51 [1.20, 1.90] Lag 3-5
    PM10 + 03:1.09 [0.71, 1.67] Lag 3-5
    Reference: Diette et al. (2007,1563991  Outcome: Asthma in the last 12 mo
                                        (493 xl
    Period of Study: Sep 2001 -Dec      v     '
    2003
    Location: East Baltimore, MD
    Age Groups: 2 to 6 yr old
    
    Study Design: Prospective cohort
    
    N: 150 with asthma
    
    150 without asthma
    Statistical Analyses:
    Student's two-tailed t-test
    Kruskal-Wallistest
    Pearson's chi square
    Fisher's exact test
    Covariates: Season of collection
    
    Dose-response Investigated? No
    
    Statistical Package: STATASE 8.0
    Pollutant: PM,0
    
    Averaging Time: 72 h
    
    60th(Median): 43.7
    
    IQR: (29-70)
    Notes: "Pollutant concentrations in the
    homes of asthmatic and control children
    who lived in the same home for their
    whole life were not different compared
    with those who had moved at least
    once."
    December 2009
                                    E-143
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Ebelt et al. (2005, 0569071
    
    Period of Study: Summer of 1998
    
    Location: Vancouver, Canada
    Outcome: spirometry
    
    Age Groups: Range from 54-86 yr
    
    mean age = 74 yr
    
    Study Design: Extended analysis of a
    repeated-measures panel study
    
    N: 16 persons with COPD
    
    Statistical Analyses: Earlier analysis
    expanded by developing mixed-effect
    regression models and by evaluating
    additional exposure indicators
    
    Dose-response Investigated? No
    
    Statistical Package: SASV8
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Mean (SD):
    Ambient PM10:17 (6)
    Exposure to ambient PM10:10.3 (4.6)
    Range (Min, Max):
    Ambient PM10: (7-36)
    Exposure to ambient PM10: (1.5-23.8)
    Monitoring Stations: 5
    Copollutant (correlation):
    Ambient PMio-25:r = 0.69
    Ambient PM25r = 0.78
    Exposure to Ambient PM10: r = 0.71
    PM Increment: Ambient PM10: 7 (IQR)
    
    Exposure to ambient PM10: 6.5 (IQR)
    
    Notes: Effect estimates are presented
    in Fig 2 and Electronic Appendix Table 1
    (only available with electronic version of
    article) and not provided quantitatively
    elsewhere.
    Reference: Fischer et al. (2007,
    1564351
    
    Period of Study: 7 wk (dates not
    specified)
    
    Location: The Netherlands
    Outcome: Respiratory Symptoms, Sore
    throat, Runny nose, Cold, Sick at home
    
    Study Design: Prospective cohort
    
    N:68
    
    Statistical Analyses: Linear regression
    model (PROC mixed)
    
    Age Groups: 10-11
    
    Lag: 1-2
    
    Statistical Package: SASv 6.11
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 56 pg/m3
    
    IQ (25th, 75th): (21,187) pg/m3
    Co pollutants:
    BS
    N02
    CO
    NO
    Increment: 10|jg/m
    
    % Increase in eNO and PM10 and
    change in spirometric lung function lag
    eNO and PM10 only
    6.5
    7.8
    0.9, 12.4) 1
    -11.3,31.0)2
                                                                                                              FVC mean (SEM)
                                                                                                             0.4
                                                                                                             0.6
        0.5)1
        1.6)2
                                                                                                              FEV, mean (SEM)
                                                                                                             -0.3 (0.5
                                                                                                             -2.1 (1.9
                                                                                                              PEF mean (SEM)
                                                                                                              -2.8 (3.3) 1
                                                                                                              7.1(12.0)2
                                                                                                              MMEF mean (SEM)
                                                                                                             -0.5(1.7
                                                                                                             -2.5 (5.9
    Reference: Forsberg et al. (1998,
    0517141
    
    Period of Study: Jan 1994-March
    1994
    
    Location: Urban and rural areas of
    Umea, Sweden
    Outcome: Respiratory Symptoms,
    Shortness of breath
    
    Wheeze, Asthma attacks, Recent
    asthma, Dry cough, Doctor-diagnosed
    asthma, Recently treated for asthma,
    Early chest illness
    
    Study Design: Cohort panel
    
    Statistical Analyses: Logistic linear
    regression
    
    Age Groups: 6-12
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Urban: 13.4|jg/m3
    Rural: 11.5|jg/m3
    Range (Min, Max):
    Urban: (0, 40.5) pg/m3
    Rural: (1.6, 29.0) pg/m3
    Copollutants (correlation):
    BS:r = 0.73
    Increment: 10|jg/m
    
    OR between prevalence of acute
    respiratory symptoms and PMi0
    exposure for urban and rural children
    lag
    Urban children:
    Cough: 1.031 (0.957,  1.112)0
                                                                                                             0.997
                                                                                                             1.018
          0.923, 1.077
          0.940, 1.103
                                                                                                              1.094(0.895, 1.338) 0-6 avg
                                                                                                              Phlegm:
                                                                                                              0.998(0.899,1.108)0
                                                                                                              1.035(0.928,1.154)1
                                                                                                              1.121
                                                                                                              1.043
                                                                                1.013, 1.240
                                                                                0.822, 1.324
                                                                                                                               0-6 avg
                                                                                                              Upper respiratory symptoms:
                                                                                                              1.004
                                                                                                              0.975
                                                                                0.949, 1.063
                                                                                                                   0.922,1.031 1
                                                                                                             0.951(0.895,1.010)2
                                                                                                             0.849(0.687, 1.050) 0-6 avg
                                                                                                             Lower respiratory symptoms:
                                                                                                             0.984(0.872,1.110)0
                                                                                                             0.919
                                                                                                             0.894
                                                                                0.812, 1.039
                                                                                                                   0.771, 1.036 2
                                                                                                             0.800(0.617, 1.038) 0-6 avg
                                                                                                             Rural children (control)
                                                                                                             Cough:
                                                                                                             0.997(0.900,1.105)0
                                                                                                              1.003
                                                                                                              0.997
                                                                                0.906, 1.112
                                                                                0.891,1.116
                                                                                                             0.855(0.655, 1.115) 0-6 avg
                                                                                                             Phlegm:
                                                                                                             1.024(0.880,1.192)0
                                                                                                             0.995(0.853,1.160)1
                                                                                                             1.117(0.956, 1.305)2
                                                                                                             1.041(0.742, 1.459) 0-6 avg
                                                                                                             Upper respiratory symptoms:
                                                                                                             1.093 0.989, 1.208 0
                                                                                                             1.018(0.918,1.130)1
    December 2009
                                    E-144
    

    -------
                  Study
    Design & Methods
    Concentrations!
    Effect Estimates (95% Cl)
                                                                                                               1.075(0.962, 1.201)2
                                                                                                               1.052(0.786, 1.407) 0-6 avg
                                                                                                               Lower respiratory symptoms:
                                                                                                               1.022(0.855,1.180)0
                                                                                                               0.998
                                                                                                               1.000
                                                                          0.855, 1.164
                                                                          0.830, 1.206
                                                                                                               0.939(0.703, 1.253) 0-6 avg
                                                                                                               OR between incidence of acute
                                                                                                               respiratory symptoms and PM10
                                                                                                               exposure in urban and rural children
                                                                                                               lag
                                                                                                               Urban Children:
                                                                                                               Cough:
                                                                                                               1.114(0.886,1.401)0
                                                                                                               0.891 (0.703, 1.130)1
                                                                                                               0.766
                                                                                                               0.817
                                                                                                               Phlegm:
                                                                          0.577, 1.017
                                                                          0.523, 1.276
                                                                                                               0.954
                                                                                                               1.056
                                                                          0.664, 1.371
                                                                          0.744, 1.501
                                                                                                                                0-6 avg
                                                                                                               1.416(0.969,2.069)2
                                                                                                               0.808(0.357, 1.827) 0-6 avg
                                                                                                               Upper respiratory symptoms:
                                                                                                               1.155(0.965, 1.383)0
                                                                                                               0.788
                                                                                                                     0.629, 0.986
                                                                                                                     0.728, 1.077 2
                                                                                                               0.770(0.549, 1.081) 0-6 avg
                                                                                                               Lower respiratory symptoms:
                                                                                                               1.060(0.828,1.356)0
                                                                                                               0.763 (0.584, 0.996) 1
                                                                                                               0.652
                                                                                                               0.519
                                                                          0.493, 0.863
                                                                          0.306, 0.882
                                                                                                               Rural Children:
                                                                                                               Cough:
                                                                                                               1.052(0.767,1.444)0
                                                                                                               0.753(0.547, 1.038)1
                                                                                                                                0-6 avg
                                                                                                               0.840
                                                                                                               0.800
                                                                                                               Phlegm:
                                                                                                                     0.571, 1.235
                                                                          0.409, 1.565
                                                                                                               1.051
                                                                                                               1.010
                                                                          0.731, 1.509
                                                                          0.693, 1.472
                                                 0-6 avg
                                                                                                               0.998(0.652, 1.528)2
                                                                                                               0.797(0.344, 1.847) 0-6 avg
                                                                                                               Upper respiratory symptoms:
                                                                                                               1.044(0.813, 1.341)0
                                                                                                               0.810
                                                                                                               0.800
                                                                          0.612, 1.072)1
                                                                          0.611,1.048)2
                                                                                                               0.714(0.417, 1.220) 0-6 avg
                                                                                                               Lower respiratory symptoms:
                                                                                                               1.079(0.756,1.539)0
                                                                                                               0.888(0.615, 1.281)1
                                                                                                                     0.472, 1.083)2
                                                                                                                     0.395, 1.711) 0-6 avg
                                                                    0.715
                                                                    0.822 .
                                                                    OR between prevalence of medication
                                                                    use and PM10 exposure in urban and
                                                                    rural  children lag
                                                                    Bronchodilator use - Urban children:
                                                                                                               0.998
                                                                                                               0.999
                                                                          0.951, 1.048
                                                                          0.952, 1.049
                                                                                                               1.006(0.953, 1.062)2
                                                                                                               0.919(0.775, 1.090) 0-6 avg
                                                                                                               Rural children:
                                                                                                               0.970(0.904,1.040)0
                                                                                                               0.959
                                                                                                               1.008
                                                                          0.893, 1.030
                                                                          0.927, 1.095
                                                                                                               1.087(0.914, 1.292) 0-6 avg
                                                                                                               OR between incidence of medication
                                                                                                               use and PM10 exposure in urban and
                                                                                                               rural children lag
                                                                                                               Bronchodilator use - Urban children:
                                                                                                               1.498(0.899,2.498)0
                                                                                                               1.049(0.565, 1.947)1
                                                                                                                     0.674, 1.954)2
                                                                                                                     0.611, 5.227) 0-6 avg
                                                                    1.148
                                                                    1.787 .
                                                                    Rural children:
                                                                    1.275 0.702,2.315  0
                                                                    0.924(0.437,1.956)1
    December 2009
                             E-145
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    1.005(0.522, 1.936)2
    1.823(0.534, 6.277) 0-6 avg
    Reference: Goncalves et al. (2005,
    0898841
    Period of Study: Dec 1992-Mar 1993.
    Dec 1992-Mar 1994
    Outcome: Respiratory
    morbidity/admissions
    Age Groups: Children <13 yr
    Study Design: Time series
    Pollutant: PM,0
    Averaging Time: 24 h
    Copollutant: S02 , 03
    PCA coefficients: PC1.PC2, PCS:
    Summer 1992/1 993:
    PMi0:0.69, 0.45, 0.13
    Solar Radiation: -0.04, 0.94 to -0.12
    Location: Sao Paulo
                                        Statistical Analyses: Principal
                                        component analysis
    
                                        Covariates: Daily mean temperature,
                                        daily mean  water vapor density, solar
                                        radiation
    
                                        Season: Summer
    
                                        Dose-response Investigated? No
    
                                        Statistical  Package: NR
    
                                        Lags Considered:  Lag 3
                                                                           Mean Temperature: 0.62, 0.44 to -0.47
    
                                                                           Mean V\Mer Vapor Density:
                                                                           0.73 to-0.46 to-0.26
                                                                           S02: 0.78 to-0.03, 0.33
                                                                           03:0.18, 0.63, 0.37
    
                                                                           Respiratory Mortality:
                                                                           0.05(0-0.02,0.81
    
                                                                           Variations explained by Principal
                                                                           Component:
                                                                           PC1:0.29
                                                                           PC2: 0.27
                                                                           PCS: 0.17
    
                                                                           Summer 1993/1994:
                                                                           PM,0: 0.38,  0.80(0-0.23
    
                                                                           Solar Radiation: 0.02, 0.09 to -0.97
    
                                                                           Mean Temperature: 0.71, 0.40 to -0.37
    
                                                                           Mean V\Mer Vapor Density:
                                                                           0.88, 0.25, 0.09
                                                                           S02: 0.01, 0.92, 0.00
                                                                           03: 0.47 to-0.06 to-0.35
    
                                                                           Respiratory Mortality: -0.73, 0.11, 0.08
    
                                                                           Variations explained by Principal
                                                                           Component:
                                                                           PC1:0.31
                                                                           PC2: 0.25
                                                                           PCS: 0.18
    
                                                                           Notes: Association between respiratory
                                                                           morbidity and air pollution more likely
                                                                           during summer with smaller contrasts in
                                                                           synoptic weather condition (summer
                                                                           1992/93) but respiratory morbidity more
                                                                           related to weather variables during
                                                                           summer with larger contrasts (summer
                                                                           1993/94).
    Reference: Gordian and Choudhury
    (2003, 0548421
    
    Period of Study: 1994-Dec 1996
    
    Location: Anchorage, Alaska
    Outcome: Asthma medication among
    school children
    
    Age Groups: Elementary school
    children (kindergarten-6th grade)
    
    Study Design: Time series
    
    Statistical Analyses: Time series
    regression model
    
    Covariates: Day of the week, month,
    time trend, temperature
    
    Season: All seasons
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 1,2, 7,14,21,28
    Pollutant: PM10
    
    Averaging Time: 24 h
    
    Mean (SD): 36.11 (30.46)
    
    Range (Min, Max): 2.96, 210.0
    
    Monitoring Stations: 1
    Model regression slope coefficient for
    PM,o (estimated SE) lag:
    
    7.25 (2.88)
    
    lag 21
    
    RR: 1.075 (1.016, 1.138)
    
    Notes: PMi0 coefficients for other lags
    were also statistically significant but not
    reported.
    December 2009
                                    E-146
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
                                       Pollutant: PMi0
    Reference: Harre et al. (1997, 0957261  Outcome: Respiratory symptoms,
    _..,-..    ,   „„, „    .,„„,,  Cough, Wheeze, Chest tightness,             .
    Period of Study: Jun 994-Aug 1 994  shortness of breath, Change in sputum  Averaging Time: 24-h avg
                                       volume, Nose, throat, or eye irritation,
                                                             '
    Location: Christchurch, New Zealand
                                       Study Design: Prospective cohort
    
                                       Statistical Analyses: Poisson, log
                                       linear regression
    
                                       Age Groups: >55
                                       -    „ .   ._
                                       Copollutants:
    
    
                                       SO
                                          2
                                       |\|Q2
                                       Increment: 35.04 pg/m
    
                                       Relative Risk (Lower Cl, Upper Cl)
                                       lag:
                                       Chest symptoms: 1.38 (1.07,1.78)1
                                       Wheeze: 0.97 (0.75,1.26)1
                                       Nebulizer Use: 0.71 (0.42,1.18)1
                                       Inhaler Use: 0.94 (0.78,1.13)1
    Reference: Hastings and Jardine
    (2002, 0303441
    
    Period of Study: 1997-1998
    
    Location: Bosnia (U.S. military camps)
    Outcome: Weekly rates of upper
    respiratory disease (URD), reported by
    the medical treatment facility in each
    military camp
    
    Age Groups: U.S. soldiers
    
    Study Design: Ecologic (at level of
    military camp)
    
    N: 5 camps
    Statistical Analyses:
    1. Pearson correlations between weekly
    URD rates and weekly PMi0 (avg and
    max)
    2.Kruskal Wallace test to compare URD
    rates in the 4 exposure quartiles
    3.  Mann Whitney test to compare
    dichotomized exposure groups (above
    and below 50th percentile)
    Dose-response Investigated? Yes
    
    Lags Considered: Weekly rates of
    URD disease were  related to avg
    weekly PM levels in the same week
    Pollutant: PM,0
    Mean (SD):
    PM10 avg: 75.5
    PM10 max: 92.9
    
    Percentiles:
    PM10 max:
    25th: 58.57
    50th: 74.55
    75th: 107.56
    PM,o avg:
    25th: 42.19
    50th: 64.17
    75th: 81.75
    
    Range (Min, Max):
    PM10 avg: 25.0, 338.7
    PM,o max: 25.0, 338.7
    Monitoring Stations: At least 1 in each
    of the 5 camps
    PM max Quartiles (combining all
    camps):
    Q1:<58.7|jg/m3
    Q2:60.1to<75.54|jg/m3
    Q3: 78.56 to <107.56 pg/m3
    Q4: >107.56 pg/m3
    For dichotomous analysis
    cutoff = 74.55 pg/m3
    PM avg Quartiles (combining all
    camps):
    Q1:<42.19|jg/m3
    Q2: 42.19to64.17 pg/m3
    03: 64.17 to 81.75 fjg/m3
    Q4:>81.75|jg/m3
    For dichotomous analysis
    cutoff =64.17 fjg/m
    
    Pearson correlation coefficients
    between URD rate and PM category [p-
    value]: PM,0 max: quartiles of PMURD
    rates
    All camps 0.203 [0.041]
    Blue Factory camp 0.277 [0.095]
    Comanche 0.165 [0.237]
    Demi 0.639 [0.123]
    McGovern 0.535 [0.177]
    Tuzla Main 0.107 [0.327]
    
    PMio max: dichotomous PMURD rates:
    All camps 0.283 [0.007]
    Blue Factory camp 0.038 [0.430]
    Comanche 0.282 [0.107]
    Demi 0.927 [0.012]
    McGovern 0.853 [0.033]
    Tuzla Main 0.155 [0.258]
    
    PM,o avg: quartiles of PM*URD rates:
    All camps 0.149 [0.101]
    Blue Factory camp 0.301 [0.077]
    Comanche 0.246 [0.141]
    Demi 0.437 [0.231]
    McGovern 0.853 [0.033]
    Tuzla Main 0.182 [0.222]
    
    PMio avg: dichotomous PMURD rates:
    All camps 0.060 [0.305]
    Blue Factory camp -0.075 [0.365]
    Comanche 0.143 [0.268]
    Demi N/A*
    McGovern N/A*
    Tuzla Main 0.123 [0.303]
    
    Kruskal Wallace p-value comparing
    URD rates across exposure quartiles:
    
    PM10 max
    All camps 0.047
    Blue Factory camp 0.321
    Comanche 0.556
    Demi 0.165
    McGovern 0.202
    Tuzla Main 0.554
    
    PMio avg	
    December 2009
                                   E-147
    

    -------
                 Study                     Design & Methods                Concentrations!            Effect Estimates (95% Cl)
    
                                                                                                         All camps 0.672
                                                                                                         Blue Factory camp 0.809
                                                                                                         Comanche 0.658
                                                                                                         Demi 0.564
                                                                                                         McGovernO.157
                                                                                                         Tuzla Main 0.891
    
                                                                                                         Mann-Whitney p-value comparing URD
                                                                                                         rates between upper and lower 50th
                                                                                                         percentileofPM:
    
                                                                                                         PM10 max
                                                                                                         All camps 0.034
                                                                                                         Blue Factory camp 0.173
                                                                                                         Comanche 0.314
                                                                                                         Demi 0.083
                                                                                                         McGovern 0.401
                                                                                                         Tuzla Main 0.481
    
                                                                                                         PMio avg
                                                                                                         All camps 0.824
                                                                                                         Blue Factory camp 0.682
                                                                                                         Comanche 0.508
                                                                                                         Demi N/A*
                                                                                                         McGovern N/A*
                                                                                                         Tuzla Main 0.656
                                                                                                         Notes: * There were no days that fell in
                                                                                                         the upper 50 percentile for PM avg in
                                                                                                         these camps
    
                                                                                                         -Rates of URD by PM quartiles for each
                                                                                                         camp presented in figures. Authors
                                                                                                         state, "Generally the avg URD rate
                                                                                                         increased with quartile of maximum
                                                                                                         exposure...the trend was not as clear
                                                                                                         for quartiles of PM10 avg exposure"
    December 2009                                                 E-148
    

    -------
                  Study
    Design & Methods
    Concentrations!
    Effect Estimates (95% Cl)
    Reference: Hong et al. (2007, 0913471   Outcome: Peak expiratory flow rate
    
    Period of Study: Mar 23-May 2004     '     '
                                       Age Groups: 3rd to 6th grade (mean
    Location: School on the Dukjeok Island  age = 95 yr)
    near Incheon City,  Korea
                                       Study Design: Panel study
    
                                       N: 43 schoolchildren
    
                                       Statistical Analyses: Mixed linear
                                       regression
    
                                       Covariates: Age, sex, height, weight,
                                       asthma history, and passive smoking
                                       exposure at home
    
                                       Dose-response Investigated? No
    
                                       Lags Considered: 0,1,2,3,4,5
                                Pollutant: PM,0
    
                                Averaging Time: 24 h
    
                                Mean (SD): 35.30 (23.48)
    
                                50th (Median): 29.36
    
                                Range (Min, Max):
    
                                (12.24-124.87)
    
                                PM Component:
    
                                Fe: mean = 0.208 (0.203) pg/m3
    
                                Median = 0.112
    
                                Range (Min, Max):  (0.061-0.806)
    
                                Mn: mean = 0.008 (0.005) pg/m3
    
                                Median = 0.007
    
                                Range (Min, Max):  (0.000-0.019)
    
                                Pb: mean = 0.051 (0.031) pg/m3
    
                                Median = 0.051
    
                                Range (Min, Max):  (0.011-0.155)
    
                                Zn: mean = 0.021 (0.021) pg/m3
    
                                Median = 0.013
    
                                Range (Min, Max):  (0.006-0.112)
    
                                Al: mean = 0.085 (0.100) pg/m3
    
                                Median = 0.031
    
                                Range (Min, Max):  (0.017-0.344)
    
                                Copollutant: PM25
                               Effect Estimate: Regression
                               coefficients of morning and daily mean
                               PEFR on PMio and metal components
                               using linear mixed-effects regression
                               Lag 1 (PM10)
                               Morning PEFR
                               Crude: IS = -0.00, p = 0.99
                               Adjusted: IS = -0.04, p = 0.37
                               Mean PEFR
                               Crude: IS = 0.00, p = 0.93
                               Adjusted: IS = -0.05, p = 0.12
                               Lag 1 (logFe)
                               Morning PEFR
                               Crude: IS =-1.26, p = 0.31
                               Adjusted: IS = -3.24, p = 0.13
                               Mean PEFR
                               Crude: IS =-1.20, p = 0.20
                               Adjusted: IS = -2.37, p = 0.15
                               Lag 1 (logMn)
                               Morning PEFR
                               Crude: IS = -4.40, p< 0.01
                               Adjusted: IS = -9.82, p< 0.01
                               Mean PEFR
                               Crude: IS = -4.05, p< 0.01
                               Adjusted: IS = -8.44, p< 0.01
                               Lag 1 (logPb)
                               Morning PEFR
                               Crude: IS = -6.79, p< 0.01
                               Adjusted: IS = -6.83, p<0.01
                               Mean PEFR
                               Crude: IS = -6.23, p< 0.01
                               Adjusted: IS = -6.37, p<0.01
                               Lag 1 (logZn)
                               Morning PEFR
                               Crude: IS = -0.55, p = 0.71
                               Adjusted: IS = -0.98, p = 0.59
                               Mean PEFR
                               Crude: IS =1.33, p = 0.24
                               Adjusted: IS =1.53, p = 0.28
                               Lag1 (logAI)
                               Morning PEFR
                               Crude: IS = -0.58, p = 0.57
                               Adjusted: IS = -2.22, p = 0.25
                               Mean PEFR
                               Crude: IS = -0.59, p = 0.45
                               Adjusted: IS = -1.48, p = 0.32
                               Regression coefficients of morning and
                               daily mean PEFR on metal components
                               ofPM10andGSTM1andGSTT1
                               genotype using linear mixed-effects
                               regression
                               Lag 1 (logPb)
                               Morning PEFR: IS =-7.26, p<0.01
                               Mean PEFR: IS =-6.43, p< 0.01
                               GSTM1
                               Morning PEFR: IS = 21.19, p = 0.23
                               Mean PEFR: IS = 20.09, p = 0.25
                               Lag 1 (logMn)
                               Morning PEFR: IS = -10.31, p<0.01
                               Mean PEFR: IS =-8.66, p< 0.01
                               GSTM1
                               Morning PEFR: IS = 21.02, p = 0.23
                               Mean PEFR: IS = 19.84, p = 0.25
                               Lag 1 (logPb)
                               Morning PEFR: IS =-7.26, p<0.01
                               Mean PEFR: IS =-6.43, p< 0.01
                               GSTT1
                               Morning PEFR: IS = 2.07, p = 0.90
                               Mean PEFR: IS =-2.39, p< 0.88
                               Lag 1 (logMn)
                               Morning PEFR: IS = -10.32, p < 0.01
                               Mean PEFR: IS =-8.67, p< 0.01
                               GSTT1
                               Morning PEFR: IS = 2.02, p = 0.90
                               Mean PEFR: IS = 2.33, p = 0.88
    December 2009
                            E-149
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Hwang et al. (2006,
    0889711
    
    Period of Study: 2001
    
    Location: Taiwan
    Outcome: Allergic rhinitis
    
    Study Design: Cross-sectional
    
    Statistical Analyses: Two-stage
    hierarchical models
    
    Age Groups: 6-15 yr
    Pollutant: PM,0
    
    Averaging Time: 1-h avg
    
    Mean (SD): 55.58 (16.57)
    
    Range (Min, Max):
    
    (29.36, 99.58)
    
    Copollutants (correlation):
    
    CO: r = 0.27
    
    N0x:r = 0.34
    
    03:r = 0.28
    
    S02:r = 0.58
    Increment: 10|jg/m
    
    Odds Ratio (Lower Cl, Upper Cl)
    lag:
    PM10 alone: 1.00 (0.99,1.02)
    , PM10: 0.99 (0.97, 1.00)
    CO, PM10:1.00 (0.99, 1.01)
    03,PM10:1.00 (0.99, 1.02)
    Gender
    Male:  1.02 (0.99,1.04)
    Female: 0.99 (0.97,1.02)
    Parental atopy*
    Yes: 1.00 (0.98, 1.03)
    No: 1.01 (0.99,  1.03)
    Parental education
    <6yr: 1.05 (0.96,1.14)
    6-8 yr: 1.03 (0.98,1.07)
    9-11 yr: 1.00 (0.98,1.03)
    12+yr: 0.99 (0.97,1.02)
    Environmental tobacco smoke
    Yes: 1.01 (0.99,1.03)
    No: 1.00 (0.98,  1.03)
    Visible mold**
    Yes: 1.02 (0.99, 1.06)
    No: 1.00 (0.98,  1.02)
    * Parental atopy was a measure of
    genetic predisposition and was defined
    as the father or the mother of the index
    child ever having been diagnosed as
    having asthma, allergic rhinitis, or atopic
    eczema.
    
    "Visible mold found in the home.
    Reference: Jalaludin et al. (2004,
    0565951
    Outcome: Respiratory symptoms,
    Wheeze, Dry cough, Wet cough
    Period of Study: Feb 1994-Dec 1994    Study Design: Longitudinal study panel
    Location: Western and southwestern
    Sydney, Australia
    Statistical Analyses: Logistic
    regression model (GEE)
    
    Age Groups: 9-11 yr
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): 22.8 (13.8)
    
    IQ Range (26th,76th): (12.00,122.8)
    
    Copollutants (correlation):
    03:r = 0.13
    
    N02:r = 0.26
    Increment: 10|jg/m
    
    Odds Ratio (Lower Cl, Upper Cl)
    
    Lag
    Wheeze
    1.01 (0.99, 1.03)0
    1.01(0.97,1.04)1
    0.99(0.96,1.03)2
    1.02(0.98, 1.06) 0-2 avg
    1.04(0.99, 1.10) 0-5 avg
    Dry Cough
    1.00(0.98, 1.03)0
    1.00(0.97, 1.03)1
    1.00(0.97,1.02)2
    1.00(0.97, 1.03) 0-2 avg
    1.03(0.98, 1.08) 0-5 avg
    Wet Cough
    1.01 (0.99, 1.04)0
    0.99(0.97, 1.01)1
    1.00(0.97,1.03)2
    0.99(0.96, 1.02) 0-2 avg
    0.99(0.94, 1.04) 0-5 avg
    Inhaled B2-agonist Use
    0.99(0.98, 1.01)0
    1.00(0.98, 1.03)1
    0.99(0.97,1.01)2
    1.00(0.97, 1.02) 0-2 avg
    1.02(0.98, 1.06) 0-5 avg
    Inhaled Corticosteroid Use
    1.00(0.99, 1.01)0
    1.00(0.99, 1.02)1
    1.00(0.99,1.02)2
    1.00(0.98, 1.02) 0-2 avg
    1.00(0.97, 1.02) 0-5 avg
    Doctor Visit for Asthma
    1.11 (1.04, 1.19)0
    1.10(1.02, 1.19)1
    1.15(1.06,1.24)2
    1.11 (1.03,1.20) 0-2 avg
    1.14(0.98, 1.31) 0-5 avg
    OR for respiratory symptoms and
    PM10 exposure by different groups
    December 2009
                                    E-150
    

    -------
                  Study                        Design & Methods                 Concentrations!             Effect Estimates (95% Cl)
    
                                                                                                                 All children
                                                                                                                 Wheeze: 1.01 (0.99,1.04)
                                                                                                                 Dry Cough: 1.00 (0.97,1.02)
                                                                                                                 Wet Cough: 1.01 (0.98,1.04)
                                                                                                                 Inhaled B2-agonist Use:
                                                                                                                 1.00(0.98,1.02)
                                                                                                                 Inhaled Corticosteroid Use:
                                                                                                                 0.99(0.98, 1.01)
                                                                                                                 Doctor Visit for asthma:
                                                                                                                 1.11(1.03,1.19)
                                                                                                                 Group 1*
                                                                                                                 Wheeze: 1.01 (0.98,1.04)
                                                                                                                 Dry Cough: 0.97 (0.94, 0.99)
                                                                                                                 Wet Cough: 1.00 (0.97,1.03)
                                                                                                                 Inhaled B2-agonist use:
                                                                                                                 1.00(0.98,1.02)
                                                                                                                 Inhaled Corticosteroid Use:
                                                                                                                 1.00(0.98,1.01)
                                                                                                                 Doctor Visit for asthma: 1.09
                                                                                                                 (0.98,1.21)
                                                                                                                 Group 2**
                                                                                                                 Wheeze: 1.01 (0.97,1.05)
                                                                                                                 Dry Cough: 1.02 (0.98,1.06)
                                                                                                                 Wet Cough: 1.01 (0.96,1.06)
                                                                                                                 Inhaled B2-agonist use:
                                                                                                                 0.99(0.94, 1.05)
                                                                                                                 Inhaled Corticosteroid Use:
                                                                                                                 0.99(0.97,1.01)
                                                                                                                 Doctor Visit for asthma:
                                                                                                                 1.12(1.02,1.23)
                                                                                                                 Group 3***
                                                                                                                 Wheeze: 1.08 (0.90,1.31)
                                                                                                                 Dry Cough: 1.01 (0.91,1.11)
                                                                                                                 Wet Cough: 1.02 (0.94,1.11)
                                                                                                                 Inhaled B2-agonist use:
                                                                                                                 0.98(0.84,1.11)
                                                                                                                 Inhaled Corticosteroid Use:
                                                                                                                 1.27(1.08, 1.49)
                                                                                                                 Doctor Visit for asthma: NR
                                                                                                                 'Group 1 consists of children with a
                                                                                                                 history of wheeze in the past 12 mo,
                                                                                                                 positive histamine challenge, and doctor
                                                                                                                 diagnosed asthma.
    
                                                                                                                 "Group 2 consists of children with a
                                                                                                                 history of wheeze in the past 12 mo and
                                                                                                                 doctor diagnosed asthma.
    
                                                                                                                 ***Group 3 consists of children only with
                                                                                                                 a history y of wheeze in the  past 12 mo.
    December 2009                                                     E-151
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Jansen, et al. (2005,
    0822361
    
    Period of Study: 1987-2000
    
    Location: Seattle, WA
    Outcome: FENO: fractional exhaled
    nitrogen oxide, Spirometry, Blood
    pressure,  Sa02: oxygen saturation,
    Pulse rate
    
    Age Groups: 60-86 yr old
    
    Study Design: Short-term cross-
    sectional case series
    
    N: 16 subjects diagnosed with COPD,
    asthma, or both
    
    Statistical Analyses: Linear mixed
    effects model with random intercepts
    
    Covariates: Age, relative humidity,
    temperature, medication use
    
    Season: winter 2002-2003
    
    Dose-response  Investigated? No
    
    Statistical Package: STATA
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Mean (SD):
    Fixed-site Monitor: 18.0
    All Subjects (N = 16)
    Indoor, home: 11.93
    Outdoor, home: 13.47
    Personal: 23.34
    Asthmatic Subjects (N = 7)
    Indoor, home: 12.54
    Outdoor, home: 11.86
    Personal: 26.88
    COPD Subjects (N = 9)
    Indoor, home: 11.45
    Outdoor, home: 14.76
    Personal: 19.91
    Range (Min, Max):
    Fixed-site Monitor 2.5, 51
    IQR:
    All Subjects
    Indoor, home: 6.93
    Outdoor, home: 9.53
    Personal: 20.72
    Asthmatic Subjects
    Indoor, home: 10.19
    Outdoor, home: 8.77
    Personal: 20.08
    COPD Subjects
    Indoor, home: 4.56
    Outdoor, home: 6.14
    Personal: 19.94
    PM Increment: 10 |ig/m
    
    Slope [95% Cl]: dependence of FENO
    concentration [ppb] on PMi0
    
    Asthmatic Subjects
    
    Indoor, home: 3.81 [-0.86: 8.50]
    
    Outdoor, home: 5.87 [2.87: 8.88]*
    
    Personal: 0.66 [-0.56:1.88]
    
    COPD Subjects
    
    Indoor, home: 2.19 [-3.48: 7.87]
    
    Outdoor, home: 4.45 [-1.11:10.01]
    
    Personal: 0.17 [-1.61:1.96]
    
    Results indicate that FENO may be a
    more sensitive biomarker of PM
    exposure than other traditional health
    endpoints.
    December 2009
                                    E-152
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Johnston, et al. (2006,
    0913861
    Period of Study:
    7mo(Apr7-Nov7, 2004)
    
    Location: Darwin, Australia
    Outcome: Asthma symptoms
    
    Age Groups: All ages
    
    Study Design: Time-series
    
    N: 251 people (130 adults, 121 children
    
    Statistical Analyses: Logistic
    regression model
    
    Covariates: Minimum air temperature,
    doctor visits for influenza and the
    prevalence of asthma symptoms and,
    the fungal spore count and both onset
    of asthma symptoms and
    commencement of reliever medication
    
    Season: "Dry season"-specific months
    NR, note Southern Hemisphere
    
    Dose-response Investigated? No
    
    Statistical Package: STATA8
    
    Lags Considered: 0-5  days
    Pollutant: PM,0
    
    Averaging Time: Daily
    
    Mean (SD): 20 (6.4)
    
    Range (Min, Max): 2.6-43.3
    
    PM Component: Vegetation fire smoke
    (95%) and motor vehicle emissions
    (5%)
    
    Monitoring Stations: 1
    
    Correlation: PM25 r = 0.90
    PM Increment: 10 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    Symptoms attributable to asthma
    Overall:!.010 (0.98,1.04)
    Adults:!.027 (0.987,1.068)
    Children:0.930 (0.966,1.060)
    Using preventer: 1.022 (0.985,1.060)
    
    Became symptomatic
    Overall: 1.240 (1.106,1.39)
    Adults: 1.277 (1.084,1.504)
    Children: 1.247 (1.058,1.468)
    Using preventer:1.317 (1.124,1.543)
    
    Used Reliever
    Overall: 1.010 (0.99,  1.04)
    Adults: 1.026 (0.990, 1.063)
    Children: 1.006 (0.960,1.055)
    Using preventer: 1.035 (1.004,1.060)
    
    Commenced Reliever
    Overall: 1.132 (0.99,  1.29)
    Adults: 1.199 (0.994, 1.446)
    Children: 1.093 (0.906,1.319)
    Using preventer: 1.194 (0.996,1.432)
    
    Commenced Oral Steroids
    Overall: 1.540 (1.01,  2.34)
    Adults: 1.752 (1.008, 3.045)
    Children: 1.292 (0.682, 2.448)
    Using preventer: 1.430 (0.888, 2.304)
    
    Asthma Attack
    Overall: 1.030 (0.95,  1.12)
    Adults: 1.08 (0.976, 1.202)
    Children: 0.861 (0.710,1.044)
    Using preventer:!.051 (0.939,1.175)
    
    Exercise induced asthma
    Overall: 0.980 (0.92,  1.05)
    Adults: 0.988 (0.902, 1.081)
    Children: 0.972 (0.844,1.119)
    Using preventer: 1.026 (0.928,1.134)
    
    Saw a health professional for asthma
    Overall: 1.030 (0.85,  1.26)
    Adults: 1.064 (0.794, 1.424)
    Children: 0.998 (0.749,1.328)
    Using preventer:0.924 (0.731,1.169)
    
    Missed school or work due to asthma
    Overall: 1.102 (0.941,1.290)
    Adults: 1.135 (0.897, 1.435)
    Children: 1.073 (0.862,1.333)
    Using preventer: 1.025 (0.857,1.228)
    
    Mean daily number of asthma
    symptoms
    Overall: 1.020 (1.001,1.031)
    Adults: 1.027 (1.005,1.049)
    Children: 1.016 (0.986,1.047)
    Using preventer: 1.034 (1.011,1.058)
    
    Mean Daily number of applications of
    reliever
    Overall: 1.020 (1.00,1.030)
    Adults: 1.032 (1.008, 1.057)
    Children: 1.002 (0.969,1.034)
    Using preventer: 1.022 (1.001,1.043)
    December 2009
                                     E-153
    

    -------
                  Study
            Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Just et al. (2002, 0354291
    
    Period of Study:Apr 1996-Jun 1996
    
    Location: Paris, France
    Outcome: Incident and prevalent
    episodes of asthma attacks, nocturnal
    cough, wheeze, symptoms of irritation,
    respiratory infections, supplementary
    use of |32-agonists, Z-transformed peak
    expiratory flow (PEF), daily PEF
    variability
    
    Age Groups: 7-15 yr old
    
    Study Design: Cohort
    
    N: 82  children
    
    Statistical Analyses: Linear
    regression, logistic regression, GEE
    
    Covariates:  Effects of time trend, day
    of the week, weather, pollen levels
    
    Season: Spring/summer
    
    Lags  Considered: 0, 0-2 mean, 0-4
    mean
    Pollutant: PM,0
    
    Averaging Time: Daily
    
    Mean (SD): 23.5 (8.4)
    
    Range (Min, Max): 9.0, 44.0
    
    Monitoring Stations: 5
    
    Copollutant (correlation):
    
    BS: 0.59
    
    S02: 0.70
    
    N02: 0.54
    
    03: 0.21
    
    Temp: 0.04
    
    Humid: -0.41
    PM Increment: 10 pg/m  for binary
    responses data (results that use odds
    ratios [ORs])
    Incident episodes of
    1) Asthma
     a lag 0:1.06 (0.61,1.83)
     b 0-2 mean: 1.09 (0.48, 2.49)
     c) 0-4 mean: 1.07 (0.44, 2.65)
    2) Nocturnal cough
     a lag 0:1.10 (0.88,1.37)
     b 0-2 mean: 1.03 (0.77,1.37)
     c) 0-4 mean: 1.11 (0.86,1.42)
    3) Respiratory infections
     a) lag 0:0.64 (0.35,1.15)
     b) 0-2 mean: 0.74 (0.38,1.43)
     c) 0-4 mean: 0.99 (0.58,1.68)
    Prevalent episodes of
    1) Asthma
     a) lag 0:1.07 (0.72,1.59)
     b) 0-2 mean: 1.18 (0.64, 2.17)
     c) 0-4 mean: 1.16 (0.63, 2.13)
    2) Nocturnal cough
     a) lag 0:1.05 (0.83,1.34)
     b) 0-2 mean: 1.10 (0.81,1.50)
     c) 0-4 mean: 1.09 (0.79,1.52)
    3) Respiratory infections
     a) lag 0:1.17 (0.68,  2.03)
     b) 0-2 mean: 1.31 (0.51,3.36)
     c) 0-4 mean: 1.71 (0.71,4.12)
    4) Eye irritation
     a lag 0:1.18 (1.01,1.39)
     b 0-2 mean: 1.28 (1.03,1.59)
     c) 0-4 mean: 1.42 (1.12,1.80)
    Analysis restricted  to days with no
    steroid  use:
    Incident episodes of
    1) Eye irritation
     a) lag 0:1.07 (0.66,1.71)
     b) 0-2 mean: 0.83 (0.45,1.53)
     c) 0-4 mean: 0.92 (0.46,1.83)
    2) Throat irritation
     a) lag 0:1.33 (0.66,  2.69)
     b) 0-2 mean: 1.28 (0.58, 2.80)
     c) 0-4 mean: 1.06 (0.38, 2.95)
    3) Nose irritation
     a lag 0: 0.74 (0.48,1.13)
     b 0-2 mean: 0.76 (0.42,1.36)
     c) 0-4 mean: 0.96 (0.53,1.73)
    Prevalent episodes of
    1) Eye irritation
     a lag 0:1.20 (0.88,1.65)
     b 0-2 mean: 1.71 (0.97,3.01)
     c) 0-4 mean: 1.97 (1.03, 3.76)
    2) Throat irritation
     a lag 0:1.23 (0.83,1.82)
     b 0-2 mean: 1.08 (0.68,1.73)
     c) 0-4 mean: 0.91 (0.47,1.73)
    3) Nose irritation
     a) lag 0:1.20 (0.91,1.58)
     b) 0-2 mean: 1.09 (0.78,1.52)
     c) 0-4 mean: 1.09 (0.73,1.61)
    Notes: The authors noted that incident
    or prevalent wheeze was not correlated
    with levels of any type of pollutant.
    Also, they state no relationship was
    observed between PEF variables and
    levels of PM.
    The authors also note that in a
    multipollutant model  assessing
    independent effects of PM and 03 on
    prevalent episodes of eye irritation
    (mean 0-4), the PM parameter
    decreased and was not significant
    (p = 0.19).
    December 2009
                                     E-154
    

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                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Kulkarni et al. (2006,
    0892571
    
    Period of Study: Nov 2002-Dec
    2003
    
    Location: Leicester, United Kingdom
    Outcome: Lung function by spirometry:
    FVC, REV,, FEV,: FVC, FEF25.75
    
    Age Groups: 8-15 yr
    
    Study Design: Cross-sectional
    
    N: 114 children, 64 provided sputum for
    assessment of carbon content of
    macrophages.
    
    Statistical Analyses:  Linear
    regressions, Spearman rank
    correlations. Mann-Whitney, Chi-square
    and unpaired t tests were used to
    compare results between asthmatic and
    non asthmatic children
    
    Covariates: BMI, sex, exercise, traffic
    PM10
    
    Dose-response Investigated? Yes
    
    Statistical Package: SPSS
    Pollutant: Primary PMi0 (pg/m )
    concentration was modeled, and was
    considered a covariate for carbon
    content of macrophages. Carbon
    content of alveolar macrophages was
    the primary variable of interest.
    
    Averaging Time: 1 yr
    SOth(Median):
    Children without asthma, 1.21
    Children with asthma, 1.81
    
    Range (Min, Max):
    Children without asthma, 0.10, 2.17
    Children with asthma, 0.17, 2.13
    
    PM Component: Carbon content in
    alveolar  macrophages
    
    Monitoring Stations: NR.
    
    Copollutant (correlation):
    Vs carbon content in macrophages
    (increment, coefficient range])
    -1.0|jg/m3, 0.1 [0.01-0.18]
    PM Increment: 1.0|jg/m
    
    % Change [Lower Cl, Upper Cl]:
    Single pollutant model:
    FEV,: -4.3 [-8.5, 0.2] p = 0.04
    R2 = 0.06
    
    Single pollutant model:
    FVC: -1.2 [-5.6, 3.2] p = 0.59
    R2 = 0.005
    
    Single pollutant model:
    FEF25.75: -8.6 [-17.3, 0.1] p = 0.05
    R2 = 0.06
    
    2 pollutant model with Macrophage
    Carbon:
    FEVi:PMio-2.9[-6.9, 1.2]
    p = 0.17
    FVC:PM100.1 [-4.4,4.6]
    p = 0.96
    FEF25.75:PMio-5.5 [-14.2, 3.1]
    p = 0.21
    Reference: Kuo, et al. (2002, 0363101
    
    Period of Study: 1-yr period (yr not
    specified)
    
    Location: Central Taiwan
    Outcome: Asthma (yes/no)
    
    Age Groups: 13-16 yr
    
    Study Design: Cohort
    
    N: 12,926 total  children
    775 asthmatic children
    8 junior high schools
    
    Statistical Analyses: Pearson
    correlation coefficients
    Logistic regression
    
    Covariates: Gender, age, residential
    area, level of parental education,
    number cigarettes smoked by family
    members,  incense burning in the home,
    frequency of physical activities
    
    Dose-response Investigated? No
    
    Statistical Package: SAS 6.12
    
    Lags Considered: Monthly avg at each
    school
    Pollutant: PM,0
    
    Averaging Time: 1 h
    
    Mean (SD):
    
    School A: 59.7
    
    School B: 65.3
    
    School C: 84.3
    
    School D: 59.2
    
    School E: 75.3
    
    School F: 60.2
    
    School G: 54.1
    
    School H: 69.0
    
    Monitoring Stations: 8 (1 for each
    school)
    PM Increment: Dichotomized annual
    avg:
    <65.9 pg/m3
    >65.9|jg/m3
    
    OR Estimate [Lower Cl, Upper Cl]
    lag:
    Crude (outcome = asthma, yes/no)
    <65.9 pg/m3:1 (ref)
    > 65.9 pg/m3: 0.837 [NR]
    
    Adjusted (outcome = asthma, yes/no)
    <65.9 pg/m3:1 (ref)
    > 65.9 pg/m3: 0.947 [0.640, 1.401]
    Notes: Asthma prevalence was highest
    in urban areas and lowest in rural areas
    
    Pearson correlation between annual
    PM levels at each school and asthma
    prevalence at each school: 0.214
    (p > 0.05)
    Reference: Lagorio et al. (2006,
    0898001
    Period of Study:
    May1999-Jun 1999
    Jan 1999-Dec 1999
    Location: Rome, Italy
    
    Outcome: Lung function of subjects
    (FVC and FEV,) with COPD, Asthma
    Age Groups:
    COPD: 50 to 80 yr
    Asthma: 18to64yr
    Study Design: Time series panel
    N: COPDN = 11; Asthma N = 11
    Statistical Analyses: Non-parametric
    Spearman correlation
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD):
    Overall: 42.8 (21. 8)
    Spring: 36.9(10.8)
    Winter: 49.0(28.1)
    Range (Min, Max): (7.9, 123)
    PM Component: NR
    PM Increment: 1 pg/m3
    They observed negative association
    between ambient PM10 and respiratory
    function (FVC and FEV,) in the COPD
    panel. The effect on FVC was seen at
    lag 24 h, 48 h, and 72 h. The effect on
    FEV, was evident at lag 72 h. There
    was no statistically significant effect of
    PM,0 on FVC and FEV, in the asthmatic
    and IHD panels.
                                        GEE
    
                                        Covariates: COPD and IHD: daily
                                        mean temperature, season variable
                                        (spring or winter), relative humidity, day
                                        of week
    
                                        Asthma:  season variable, temperature,
                                        humidity, and (3-2-agonist use
    
                                        Season: Spring and winter
    
                                        Dose-response Investigated? Yes
    
                                        Statistical Package: STATA
    
                                        Lags Considered: 1-3 days
                                        Monitoring Stations: Two fixed sites:
                                        (Villa Ada and Istituto superior di Sanita)
    
                                        Copollutant (correlation):
                                        N02r = 0.45
                                        03r = -0.36
                                        CO r = 0.55
                                        S02r = 0.21
                                        PM,0.25r = 0.61
                                        PM25r = 0.93
                                        P Coefficient (SE)
                                        COPD
                                        FVC(%) 24 h -0.66 (0.30)
                                        48-h -0.75 (0.35)
                                        72-h -0.94 (0.47)
                                        FEV,(%) 24 h -0.37 (0.27)
                                        48-h-0.58 (0.31)
                                        72-h -0.87 (0.43)
                                        Asthma
                                        FVC(%)24h-0.12(0.24)
                                        48-h -0.09 (0.29
                                        72-h -0.08 (0.36
                                        FEV,(%) 24 h -0.28 (0.28)
                                        48-h-0.40 0.34
                                        72-h -0.40 0.43
    December 2009
                                    E-155
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Lee, et al. (2007, 0930421
    
    Period of Study: 2000-2001
    
    Location: South-Western Seoul
    Metropolitan area, Seoul, South Korea
    Outcome: PEFR (peak expiratory flow
    rate), lower respiratory symptoms (cold,
    cough, wheeze)
    
    Age Groups: 61-89 yr (77.8 mean age)
    
    Study Design: Longitudinal panel
    survey
    
    N: 61 adults
    
    Statistical Analyses: Logistic
    regression model
    
    Covariates: Temperature (Celsius),
    relative humidity, age, season
    
    Dose-response Investigated? No
    
    Statistical Package: SAS 8.0
    
    Lags Considered: 0-4 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 71.40 (30.69)
    
    Percentiles: 25th: 43.47
    
    SOth(Median): 74.92
    
    75th: 87.54
    
    Range (Min, Max):
    
    26.23, 148.34
    
    Monitoring Stations: 2
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]
    lag:
    
    PEFR (peak expiratory flow rate)
    
    -0.39 (-0.63 to-0.14)
    
    1day
    
    relative odds of a lower respiratory
    symptom (cold, cough, wheeze)
    
    1.015(0.900,1.144)
    
    1day
    Reference: Lewis, et al. (2005,
    081079)
    
    Period of Study:
    Winter 2001-spring 2002
    
    Location: Detroit,  Michigan, USA
    Outcome: Poorer lung function
    (increased diurnal variability and
    decreased forced expiratory volume)
    
    Age Groups: 7-11  yr
    
    Study Design: longitudinal cohort study
    
    N: 86 children
    
    Statistical Analyses: descriptive
    statistics and bivariate analyses of
    exposures, multivariable regression
    models that included interaction terms
    between exposure measures and CS
    use or, alternatively, presence of a URI,
    multivariate analog of linear regression.
    
    Covariates: sex, home location, annual
    family income, presence of one or more
    smokers in household, race, season
    (entered as dummy variables), and
    parameters to account for intervention
    group effect.
    
    Season: Winter 2001 (Feb 10-23),
    spring 2001 (May 5-18), summer 2001
    (Jul 14-27), fall  2001 (Sep 22-Oct 5),
    winter 2002 (Jan 18-31), and spring
    2002 (May 18-31).
    
    Dose-response Investigated? No
    
    Lags Considered: 1-2 days
    
    3-5 days
    Pollutant: PM,0
    
    Averaging Time: 2 wk
    
    Mean (SD): Eastside 23.0 (13.5)
    
    Southwest 28.2 (16.1)
    
    Range (Min, Max): 2.9, 70.9
    
    PM Component: ("likely" in southwest
    site) carbon and diesel emissions
    
    Monitoring Stations: 2
    
    Copollutant:
    
    PM25 0.93
    
    03 Daily mean 0.59
    
    038-h peak 0.57
    PM Increment: 19.1 pg/m
    
    Lung function among children
    reporting use of maintenance CSs
    Diurnal variability FEVi
    Lag 1:1.53 [-0.85, 3.90]
    Lag 1:2.94 [-1.07, 6.96] PM10 + 03
    Lag 2: 5.32 [0.32, 10.33]
    Lag 2:13.73 [8.23, 19.23] PM10 + 03
    Lag 3-5:1.46 [-2.21,5.13]
    Lag 3-5: 3.30 [0.58, 6.02] PM,0 + 03
    Lowest daily value FEV,
                                                                                                                Lag 1:-0.28
                                                                                                                Lag 1:-6.25
                                                                                                                Lag 2:-2.21
                                                                                                                Lag 2:-5.97
               -2.34, 1.77]
                        -1.36] PM,o
               -3.97 to-0.46]
               -11.06 to-0.87] PM10 + 03
    Lag 3-5: -2.58 [-7.65, 2.49]
    Lag 3-5:1.98 [-0.38, 4.33] PM10 + 03
    Lung function among children
    reporting presence of URI on day of
    lung function assessment
    Diurnal variability FEVi
                                                                                                                Lag 1:3.51
                                                                                                                Lag 1:3.21
                                                                                                                Lag 2:1.12
                                                                                                                Lag 2: 5.40
                                                   -4.52,11.55]
                                                   -1.28,7.71] PM10 + 03
                                                   -4.62, 6.86]
                                                   -0.82, 11.62] PM10 + 03
                                        Lag 3-5: 3.90 [0.34, 7.47]
                                        Lag 3-5: 6.27 [0.07, 12.47] PM,0 + 03
                                        Lowest daily value FEV,
                                        Lag 1:-2.72 [-9.47, 4.03]
                                        Lag 1:-13.11 [-21.59 to-4.62] PM,0 +
                                        03
                                        Lag 2: 0.24 [-5.10, 4.63]
                                        Lag 2:-3.32 [-6.83, 0.18] PM,o + 03
                                        Lag 3-5: -4.48 [-8.36, 0.60]
                                        Lag 3-5: -3.17 [-5.82 to -0.51] PM10 + 03
    December 2009
                                    E-156
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Mar et al. (2004, 0573091
    
    Period of Study: 1997-1999
    
    Location: Spokane, Washington
    Outcome: Respiratory symptoms
    
    Age Groups: Adults: Ages 20-51 yr
    
    Children: Ages 7-12 yr
    
    Study Design: Time-series
    
    N: 25 people
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Temperature, relative
    humidity, day of-the-wk
    
    Statistical Package: STATA 6
    
    Lags Considered: 0-2 days
    Pollutant: PM,0
    Mean (SD):
    1997:24.5(18.5)
    1998:20.6(12.3)
    1999:16.8(8.0)
    
    Monitoring Stations: 1 station
    
    Copollutant (correlation):
    PM10
    PM1:r = 0.48
    PM25:r = 0.61
    PM10.25:r = 0.93
    PM Increment: 10 pg/m
    
    OR Estimate [Lower Cl, Upper Cl]
                                                                                                                 Adult Respiratory symptoms:
                                                                                                                 Wheeze: 1.01 [0.93,1.09] lag 0
                                                                                                                 0.98[0.91,  1.06] lag 1
                                                                                                                 0.99[0.92,  1.06] lag 2
                                                                                                                 Breath: 1.02[0.96,1.08] lag 0
                                                                                                                 1.01[0.97,1.06] lag 1
                                                                                                                 1.02(0.97,  1.06] lag 2
    
                                                                                                                 Cough: 0.96[0.88,1.05] lag 0
                                                                                                                 0.97[0.90,  1.04
                                                                                                                 0.98[0.92,  1.05
                                                       lag 2
                                                                                                                 Sputum: 1.01 [0.92,1.12] lag 0
                                                                                                                 0.99[0.91,  1.08] lag 1
                                                                                                                 1.00(0.93,  1.08] lag 2
    
                                                                                                                 Runny Nose: 0.98[0.93,1.04] lag 0
                                                                                                                 0.97[0.93,  1.02] lag 1;0.97[0.94, 1.01]
                                                                                                                 lag 2
    
                                                                                                                 Eye Irritation: 0.97[0.87,1.08] lag 0
                                                                                                                 0.97[0.88,  1.06
                                                                                                                 0.97[0.91,  1.04
                                                                                           lag 2
                                                                                                                 Lower Symptoms: 0.96[0.91, 1.02]
                                                                                                                 lagO
                                                                                                                 0.95[0.89,  1.00] lag 1
                                                                                                                 0.95[0.90,  1.00] lag 2
    
                                                                                                                 Any Symptoms: 0.97[0.93,1.02] lag 0
                                                                                                                 0.96[0.91,  1.00
                                                                                                                 0.95(0.91,0.99
                                                                                              1
                                                                                           lag 2
                                                                                                                 Children Respiratory symptoms:
                                                                                                                 Wheeze: 0.92(0.71,1.18] lag 0
                                                                                                                 0.89[0.64, 1.24] lag 1
                                                                                                                 0.95[0.69, 1.31] lag 2
    
                                                                                                                 Breath: 1.04(0.95,1.15] lag 0
                                                                                                                 1.04(0.95,  1.15
                                                                                                                 1.06(0.95,  1.19
                                                                                           lag 2
                                                                                                                 Cough: 1.09(1.02,1.16] lag 0
                                                                                                                 1.08(1.02,1.14] lag  1
                                                                                                                 1.10(1.02,1.18] lag  2
    
                                                                                                                 Sputum: 1.08(0.98,1.17] lag 0
                                                                                                                 1.07(0.98,1.17]lag1
                                                                                                                 1.07(0.98,  1.16] lag  2
    
                                                                                                                 Runny Nose: 1.08(1.00,1.16] lag 0
                                                                                                                 1.081.02,  1.15
                                                                                                                 1.081.02,1.14
                                                                                           lag 2
                                                                                                                 Eye Irritation: 1.06(0.74,1.51] lag 0
                                                                                                                 0.94(0.70,  1.26] lag 1
                                                                                                                 0.99[0.88,  1.12]lag2
    
                                                                                                                 Lower Symptoms: 1.07(1.00,1.14]
                                                                                                                 lagO
                                                                                                                 1.06(0.98,  1.15
                                                                                                                 1.07(0.95,  1.19
                                                                                           lag 2
                                                                                                                 Any Symptoms: 1.07(1.02,1.11] lag 0
                                                                                                                 1.09(1.03,1.15] lag 1
                                                                                                                 1.10(1.03,1.17] lag 2	
    December 2009
                                     E-157
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Mar et al. (2005, 0875661
    
    Period of Study: 1999-2001
    
    Location: Seattle, Washington
    Outcome: Pulmonary function (arterial   Pollutant: PMi0
    oxygen saturation) and cardiac function
    (heart rate and blood pressure)         Averaging Time: 24-h avg
    
    Study Design: Time series
    
    N:88
    
    Statistical Analyses: Linear logistic
    regression
    
    Age Groups: >57
                                        Increment: 10|jg/m
    
                                        % Increase (Lower Cl, Upper Cl)
                                        Lag
                                        Indoor
                                        Systolic: 0.92 (-0.95, 2.78) 0
                                        Diastolic: 0.63 (-0.29, 1.56)0
    
                                        Outdoor
                                        Systolic:-0.10 (-1.37,1.18)0
                                        Diastolic: -0.03 (-0.79, 0.73) 0
    
                                        Nephelometer
                                        Systolic: 0.35 (-0.91,1.61)0
                                        Diastolic:-0.12 (-0.91, 0.67)0
    
                                        % Increase between heart rate and
                                        PM10 exposure for people >67
                                        PM10
                                        Indoor:  0.02 (-0.54, 0.58) 0
                                        Outdoor:-0.48 (-1.03, 0.06)0
                                        Nephelometer:-0.31 (-0.76,0.14)0
    Reference: McCormack et al. (2009,
    1998331
    Period of Study: Sep 2001-Apr 2004
    
    Location: East Baltimore, Maryland
    Outcome: Asthma symptoms
    
    Study Design: Panel
    
    Statistical Analysis: Chi-square,
    Student t-test, Negative binomial
    regression models with GEE, Logistic
    regression with GEE
    
    Statistical Package: StataSE
    
    Age Groups: Asthmatic children aged
    2-6 yr
    Pollutant: PMio.2.5, PM2.5
    
    Averaging Time: 3 days
    
    Mean (SD) Unit:
    
    PMio-25:17.4 + 21.2 pg/m3
    
    PM25: 40.3 + 35.4 pg/m3
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 10|jg/m
    
    Relative Risk (Min Cl, Max Cl) Lag
    
    Bivariate Models, PM10.2.5
    Cough, wheezing, chest tightness:
    1.05(0.99-1.10), p = 0.08
    Slow down: 1.08 (1.03-1.13). p< 0.01
    Symptoms with running:
    1.03(0.97-1.09). p = 0.39
    Nocturnal symptoms:
    1.06(1.01-1.11), p = 0.03
    Limited speech:
    1.11 (1.05-1.18), p< 0.01
    Rescue medication use:
    1.06(1.02-1.11), p< 0.01
    
    Bivariate Models, PM25
    Cough, wheezing, chest tightness:
    1.01 (0.98-1.05), p = 0.41
    Slowdown: 1.00 (0.97-1.04), p = 0.85
    Symptoms with running:
    1.04(1.01-1.07), p = 0.14
    Nocturnal symptoms:
    1.02(0.98-1.05), p = 0.37
    Limited speech:
    1.01 (0.95-1.07), p = 0.33
    Rescue medication use:
    1.03(1.00-1.60), p = 0.06
    
    Multivariate Models, PM10-25
    Cough, wheezing, chest tightness: 1
    .06(1.01-1.12), p = 0.02
    Slow down: 1.08 (1.02-1.14), p = 0.01
    Symptoms with running:
    1.00(0.94-1.08), p = 0.81
    Nocturnal symptoms:
    1.08(1.01-1.14), p = 0.02
    Limited speech:
    1.11 (1.03-1.19), p< 0.01
    Rescue medication use:
    1.06(1.01-1.10), p = 0.02
    
    Multivariate Models, PM25
    Cough, wheezing, chest tightness:
    1.03(0.99-1.07), p = 0.18
    Slow down:
    1.04(1.00-1.09), p = 0.06
    Symptoms with running:
    1.07(1.02-1.11), p< 0.01
    Nocturnal symptoms:
    1.06(1.01-1.10), p = 0.01
    Limited speech:
    1.07(1.00-1.14), p = 0.04
    Rescue medication use:
    1.04(1.01-1.08), p = 0.04
    December 2009
                                    E-158
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Mortimer et al. (2008,
    1872801
    Period of Study: 1989-2000
    Location: Joaquin Valley, California
    Outcome: Respiratory Symptoms,
    Decreased lung function
    Study Design: Time series
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Copollutants (correlation):
    Statistical Analyses:
    Deletion/Substitution/Addition algorithm  C0: r = °'05
    (GEE)                              N02:r = 0.30
    Logistic linear regression              0 • r = 0 39
    Age Groups: 6-11
    Increment: NR
    p(SE):
    FVC:
    PM,o (age 0-3 yr): 0.0121 (0.0037)
    FEV,:PM10 (age 0-3 yr): 0.0102
    (0.0034)
    PEF:
    PM10 (Mother smoked during
    pregnancy):
    -0.0102(0.0039)
    Reference: Mortimer et al. (2002,
    0302811
    Period of Study: Jun-Aug 1993
    Location: Eight urban areas of the
    U.S.: Bronx and East Harlem, NY
    Baltimore, MD
    Washington, DC
    Detroit, Ml
    Cleveland,  OH
    Chicago, IL
    and St. Louis, MO.
    Outcome: peak expiratory flow rate
    (PEFR) and symptoms
    Age Groups: 4-9 yr
    Study Design: Cohort study
    N: 846 children with a history of asthma
    Statistical Analyses: Mixed linear
    models and GEE
    Covariates: Day of study, previous 12-
    h mean temperature, urban area, diary
    number, rain in the past 24 h
    Season: Summer
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: 0,1,2,3,4,5,6,1-
    5 avg, 1-4 avg, 0-4 avg, 0-3 avg
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (SD): 53
    Monitoring Stations: NR
    Copollutant (correlation):
    8-havg03: r = 0.51
    PM Increment: 20 pg/m3
    Effect Estimate [Lower Cl, Upper Cl]:
    (RR estimates are odds ratios for
    incidence of morning asthma symptoms
    using the avg of lag 1-2)
    3 urban areas (DE, CL, CH)
    Single pollutant: OR = 1.26 (1.00-1.59)
    03+PM,o: OR = 1.25 (0.97-1.61)
    03+S02 +N02+PM,o: OR = 1.14 (0.80-
    Reference: Moshammer and
    Neuberger (2003, 0419561
    Period of Study: 2000-2001
    Location: Linz, Austria
    Outcome: Lung Function: FVC, FEV,,
    MEF25, MEF50, MEF75, PEF, LQ Signal,
    PAS Signal
    Age Groups: Ages 7 to 10
    Study Design: Case-crossover
    N: 161 children
    1898-2120 "half-h means"
    Statistical Analyses: Correlations
    Regression Analysis
    Covariates: Morning, evening, night
    Season: Spring, summer, winter, fall
    Dose-response Investigated? No
    Pollutant: PM10
    Averaging Time: 8 h
    Daily Means
    Mean (SD): 23.13 (20.08)
    Range (Min, Max): (NR,  190.79)
    Monitoring Stations: 1
    Copollutant (correlation):
    LQ = 0.751
    PAS = 0.406
    Notes: "Acute effects of 'active particle
    surface' as measured by diffusion
    charging were found on pulmonary
    function (FVC, FEVi,MEF50) of
    elementary school children and on
    asthma-like symptoms of children who
    had been classified as sensitive."
    Reference: Moshammer et al. (2006,
    0907711
    Period of Study: 2000-2001
    Location: Linz, Austria
    
    
    
    
    
    
    
    
    
    
    Outcome: Respiratory symptoms and
    decreased lung function
    Age Groups: Children ages 7-10
    Study Design: Time-series
    
    N: 163 children
    Statistical Analyses: GEE model
    Covariates: Sex, age, height, weight
    Dose-response Investigated? NR
    Statistical Package: NR
    
    Lags Considered: 1
    
    
    Pollutant: PM10
    Averaging Time: 8 h
    Mean (SD):
    Maximum 24 h: 76.39
    
    Annual avg: 19.06
    Percentiles:
    8-h mean 25th: 14.39
    8-h mean SOth(Median): 24.85
    8-h mean 75th: 38.82
    Monitoring Stations: 1 station
    Copollutant (correlation):
    PM,:r = 0.91
    PM25:r = 0.93
    N02:r = 0.62
    
    PM Increment: 10 pg/m3
    % change in Lung Function per
    Af\ nnltVkt
    lu |jg/m3
    FEV:0.11
    FVC: 0.06
    FEV05:-0.19
    MEF75%: -0.30
    MEF50%: -0.36
    MEF25%: 0.41
    PEF: 0.22
    % change in Lung Function per IQR
    FEV: -0.27
    FVC: -0.07
    FEV05:-0.47
    MEF75%: -0.74
    MEF50%: -0.86
    MEF25%: 0.98
    PEF: -0.54
    December 2009
                                    E-159
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Neuberger et al. (2004,
    0932491
    
    Period of Study: Sep 1999-Mar 2000
    
    Location: Vienna, Austria
    Outcome: Ratio measure: Time to peak
    tidal expiratory flow divided by total
    expiration time (i.e., tidal lung function,
    a surrogate for bronchial obstruction)
    
    Age Groups: 3.0-5.9 yr (preschool
    children)
    
    Study Design: Longitudinal prospective
    cohort
    
    N: 56 children
    
    Statistical Analyses: Mixed models
    linear regression, with autoregressive
    correlation structure
    
    Covariates: Age, sex, respiratory rate,
    phase angle, temperature,
    kindergarten, parental education,
    observer (also in sensitivity analyses:
    height, weight, cold/sneeze on same
    day, heating with fossil fuels, hair
    cotinine, number of tidal slopes used to
    measure tidal lung function)
    
    Dose-response Investigated? No
    
    Statistical Package: SAS 8.0
    
    Lags Considered: 0
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Copollutant (correlation):
    PM2.5 (r = 0.94) in Vienna
    PM Increment: Interquartile range (NR)
    
    Change in mean associated with an
    IQR increase in PM (p-value)
    
    lag
    
    -1.067(0.241)
    
    lagO
    Reference: Neuberger et al. (2004,
    0932491
    
    Period of Study: Oct. 2000-May 2001
    
    Location: Linz, Austria
    Outcome: Forced oscillatory resistance
    (at zero Hz), FVC, FEV,, MEF25, MEF50,
    MEF75, PEF
    
    Age Groups: 7-10 yr
    
    Study Design: Longitudinal prospective
    cohort
    
    N: 164 children
    
    Statistical Analyses: Mixed models
    linear regression with autoregressive
    correlation structure
    
    Covariates: sex, time and individual
    
    Season: Oct-May
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 0-7
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Monitoring Stations: 1
    PM Increment: 1 pg/m
    
    Notes: No significant associations
    between PM10 and the metrics of lung
    function were reported. The authors
    state they only reported significant
    associations, so results are assumed to
    be null.
    Reference: Odajima et al. (2008,
    1920051
    Period of Study: Apr 2003-Mar 2004
    
    Location: Fukuoka, Japan
    Outcome: PEF
    
    Study Design: Panel/Field
    
    Statistical Analysis: GEE
    
    Statistical Package: SAS
    
    Covariates: Age, sex, growth index,
    temperature, N02, 03
    
    Age Groups: Asthmatic children, 4-11
    yrold
    Pollutant: PM,0
    
    Averaging Time: 3 h
    Mean (SD) Unit:
    Warmer months, 5-8 am
    SPM:40.7|jg/m3
    N02:15.2 ppb
    03:17.7ppb
    
    Warmer months, 7-1 Opm
    SPM:41.5|jg/m3
    N02: 20.0 ppb
    03:28.1 ppb
    
    Colder  months, 5-8am
    SPM:32.6|jg/m3
    N02: 20.5 ppb
    03:17.5 ppb
    
    Colder  months, 7-1 Opm
    SPM:34.7|jg/m3
    N02: 28.0 ppb
    03:19.4 ppb
    
    Range (Min, Max):
    Increment: 10|jg/m
    
    Relative Risk (Min Cl, Max Cl)
    
    Lag
    Apr-Sep, morning sample, multi-
    pollutant::
    SPM, 5am-8am: -0.6 (-1.228, 0.028)
    SPM, 2am-5am: -0.78 (-1.399,  -0.161)
    SPM, 11pm-2am:-0.612 (-1.180,-
    0.045)
    SPM, 8pm-11am:-0.732 (-1.318,-
    0.145)
    03,5am-8am:-0.575 (-1.569, 0.419
    03, 2am-5am: -0.052 (-0.997, 0.893
    03,11pm-2am:-0.305 (-1.269,  0.658)
    03,8pm-11am:-0.416 (-1.283,  0.451)
    N02, 5am-8am:-0.3 (-2.246,1.645)
    N02,2am-5am: 0.265 (-1.354,  1.885)
    N02, 11pm-2am: -0.187 (-1.447, 1.073)
    N02,8pm-11am: 0.432 (-0.689, 1.553)
    
    Single-pollutant model:
    SPM, 5am-8am:-0.67 (-1.236,-0.104)
    SPM, 2am-5am:-0.761  (-1.328,-0.194)
    SPM, 11pm-2am:-0.661 (-1.159,-
    December 2009
                                    E-160
    

    -------
                 Study
    Design & Methods
    Concentrations!
    Effect Estimates (95% Cl)
                                                                         Warmer months, 5-8am
                                                                         SPM:(11.0, 126.0)
                                                                         N02: (1.3, 44.7)
                                                                         03: (0.3, 52.3)
    
                                                                         Warmer months, 7-1 Opm
                                                                         SPM: (8.3, 191.3)
                                                                         N02: (3.0, 51.3)
                                                                         03: (1.3, 71.3)
    
                                                                         Colder months, 5-8am
                                                                         SPM: (9.0, 160.0)
                                                                         N02: (1.3, 44.0)
                                                                         03: (0.6, 48.7)
    
                                                                         Colder months, 7-1 Opm
                                                                         SPM: (10.3, 131.0)
                                                                         N02: (3.6, 49.0)
                                                                         03: (1.0, 60.0)
    
                                                                         Copollutant (correlation):
                                                                         Warmer months (24-h mean):
                                                                         03:r = 0.32
                                                                         N02:r = 0.30
    
                                                                         Colder months (24-h mean):
                                                                         03:r = -0.02
                                                                         N02:r = 0.45
                                                                  0.163)
                                                                  SPM, 8pm-11am:-0.714 (-1.212, -
                                                                  0.215)
    
                                                                  Evening sample, multi-pollutant model
                                                                  SPM, 7pm-10pm: -0.449 (-1.071, 0.174)
                                                                  SPM, 4pm-7pm:-0.434 (-1.122, 0.254)
                                                                  SPM, 1pm-4pm: -0.415 (-1.015, 0.184)
                                                                  SPM, 10am-1pm:-0.522 (-1.199, 0.155)
                                                                  03,7pm-10pm:-0.22 (-1.171, 0.731)
                                                                  03, 4pm-7pm: -0.118 (-0.809, 0.574)
                                                                  03, 1pm-4pm:-1.086 (-0.888, 0.516)
                                                                  03,10am-1pm:-0.315 (-1.123, 0.493)
                                                                  N02, 7pm-10pm: 0.296 (-0.806, 1.397)
                                                                  N02,4pm-7pm: 0.220 (-0.818, 1.258)
                                                                  N02, 1pm-4pm: 0.438 (-0.568, 1.444)
                                                                  N02, 10am-1pm: 0.536 (-0.546, 1.617)
    
                                                                  Single-pollutant model:
                                                                  SPM, 7pm-10pm: -0.449 (-0.956, 0.058)
                                                                  SPM, 4pm-7pm:-0.449 (-1.029, 0.131)
                                                                  SPM, 1pm-4pm: -0.414 (-0.943, 0.115)
                                                                  SPM, 10am-1pm: -0.486 (-1.051, 0.079)
    
                                                                  Oct-Mar, morning sample,  multi-
                                                                  pollutant::
                                                                  SPM, 5am-8am: 0.290 (-0.279, 0.859)
                                                                  SPM, 2am-5am: 0.431 (-0.173,1.036)
                                                                                                            SPM, 11pm-2am: 0.304
                                                                                                            SPM, 8pm-11am: 0.010
                                                                                       -0.311,0.919)
                                                                                       -0.523, 0.543)
                                                                                                            03, 5am-8am: -0.415 (-1.568, 0.738)
                                                                                                            03,2am-5am:-0.046 (-1.245,1.153)
                                                                                                            03,11pm-2am: 0.004 (-1.265,1.273)
                                                                                                            03,8pm-11am:-0.470 (-2.017,1.077)
                                                                                                            N02, 5am-8am: -0.319 (-2.269,1.631)
                                                                                                            N02,2am-5am: 0.262 (-1.777, 2.300)
                                                                                                            N02, 11pm-2am: 0.609 (-1.132, 2.350)
                                                                                                            N02, 8pm-11am: 0.155 (-1.545, 1.856)
    
                                                                                                            Single-pollutant model:
                                                                                                            SPM, 5am-8am: 0.308 (-0.189, 0.805
                                                                                                            SPM, 2am-5am: 0.485 (-0.026, 0.996
                                                                                                            SPM, 11pm-2am: 0.486 (-0.049, 1.022)
                                                                                                            SPM, 8pm-11am: 0.100 (-0.414, 0.613)
                                                                                                            Evening Sample, Multi-pollutant Model
                                                                                                            SPM, 7pm-10pm: 0.059 (-0.397, 0.515)
                                                                                                            SPM, 4pm-7pm: 0.360 (-0.093, 0.812)
                                                                                                            SPM, 1pm-4pm: 0.357 (-0.157, 0.871)
                                                                                                            SPM, 10am-1pm: 0.169 (-0.394, 0.731)
                                                                                                            03,7pm-10pm:-0.656 (-2.394, 1.083)
                                                                                                            03,4pm-7pm: 0.046 (-1.140, 1.232)
                                                                                                            03, 1pm-4pm: 0.164 (-1.038, 1.365)
                                                                                                            03,10am-1pm: 0.665 (-0.613,1.942)
                                                                                                            N02, 7pm-10pm: -0.415 (-2.444, 1.613)
                                                                                                            N02, 4pm-7pm: -0.144
                                                                                                            N02,1pm-4pm:-0.181
                                                                                      -1.490, 1.202)
                                                                                      -1.821, 1.459)
                                                                                                            N02,10am-1pm: 0.194 (-1.503,1.890)
    
                                                                                                            Single-pollutant model:
                                                                                                            SPM, 7pm-10pm: 0.071 (-0.388, 0.529)
                                                                                                            SPM, 4pm-7pm: 0.318 (-0.123, 0.758
                                                                                                            SPM, 1pm-4pm: 0.317 (-0.171, 0.804
                                                                                                            SPM, 10am-1pm: 0.112 (-0.412, 0.636)
    December 2009
                            E-161
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Peacock et al. (2003,
    0420261
    Period of Study: Nov 1996-Feb 1997
    
    Location: Southern England
    Outcome: Reduced peak expiratory
    flow rate (PEFR)
    
    Age Groups: 7-13 yr
    
    Study Design: Time-series
    
    N:179
    
    Statistical Analyses: GEE, multiple
    regression
    
    Covariates: Day of the week, 24-h
    mean outside temperature.
    
    Season: Winter
    
    Dose-response Investigated? No
    
    Statistical Package: STATA
    
    Lags Considered: Same day, lag 1, lag
    2, 5-day ma
    Pollutant: PM,0
    
    Averaging Time: Daily
    Mean (SD):
    Rural  (nationally validated) 21.2 (11.3)
    Rural  (locally validated) 18.7 (11.3)
    Urban 118.4 (9.8)
    Urban 2 22.7 (10.6)
    
    Percentiles:
    10th
    Rural  (nationally validated) 11.0
    Rural  (locally validated) 9.0
    Urban 1 10.5
    Urban 2 12.5
    90th
    Rural  (nationally validated) 33.0
    Rural  (locally validated) 32.5
    Urban 1 32.0
    Urban 2 36.0
    
    Range (Min, Max):
    Rural  (nationally validated) 7.0, 82.0
    Rural  (locally validated) 6.6, 87.9
    Urban 1 4.7, 62.8
    Urban 2 6.7, 63.7
    
    Monitoring Stations: 3
    
    Co pollutants:
    N02
    03
    S02
    S042"
    Increment: 10|jg/rrf
    Odds Ratio (Lower Cl, Upper Cl)
    Lag
    Change in PEFR
    Community
    -0.04 (-0.11, 0.03)0
    0.03 (-0.04, 0.05) 1
                                                                                                                -0.01
                                                                                                                -0.10
          -0.07, 0.05) 2
          -0.25, 0.05)
                                                                                                                0-4 avg
    
                                                                                                                Local
                                                                                                                -0.01 (-0.06, 0.03) 0
                                                                                                                0.04(0.01,0.08)1
                                                                                                                0.01 (-0.04, 0.05) 2
                                                                                                                0.04 (-0.05, 0.13)
                                                                                                                0-4 avg
    
                                                                                                                20% decrease in PEFR
                                                                                                                All children
                                                                                                                1.012(0.992,1.031)0
                                                                                                                1.016(0.995, 1.036)1
                                                                                                                1.013
                                                                                                                1.037
                                                                                  1.000, 1.025
                                                                                  0.992, 1.084
                                                                                                                0-4 avg
    
                                                                                                                Wheezy Children Only
                                                                                                                1.016(0.986,1.047)0
                                                                                                                1.030
                                                                                                                1.018
                                                                                  1.001, 1.060
                                                                                  0.995, 1.041
                                                                                                                1.114(1.057,1.174)
                                                                                                                0-4 avg
    Reference: Peled, et al. (2005,
    1560151
    
    Period of Study: 5-6 wk between Mar-
    Jun 1999 and Sep-Dec 1999.
    
    Location: Ashdod, Ashkelon and
    Sderot, Israel
    Outcome: Reduced peak expiratory
    flow (PEF)
    
    Age Groups: 7-10 yr
    
    Study Design: Nested cohort study
    
    N:285
    
    Statistical Analyses:  Time series
    analysis, generalized linear model,
    GEE, one-way ANOVA
    
    Covariates: seasonal  changes,
    meteorological conditions and personal
    physiological, clinical and
    socioeconomic measurements
    
    Season: Spring, fall
    
    Dose-response Investigated? No
    
    Statistical Package: STATA
    Pollutant: PM,0
    
    Averaging Time: Daily
    
    Mean:
    
    Ashkelon: 67.1
    
    Sderot: 52.9
    
    Ashdod: 31.0
    
    PM Component: Local industrial
    emissions, desert dust, vehicle
    emissions and emissions from two
    electric power plants
    
    Monitoring Stations: 6
    
    Copollutant: PM25
    PM Increment: 1 pg/m
    
    P coefficient (SE) [96% Cl]
    
    Sderot:
    
    PM10 MAX:-0.34 (0.41) [-1.16, 0.46]
    
    PM10 MAX x sin(u2 day): 0.84 (0.22)
    [0.405, 1.28]
    
    PM,o MAX x cos (u1 day):-1.61 (0.41)
    [-2.43, 0.79]
    
    PM,o MAXx sin (u1 day): 0.44 (0.120)
    [-0.68-0.21]
    
    In Sderot, an interaction between PM10
    and the sequential day were
    significantly associated with PEF.
    Reference: Pitard, et al. (2004,
    0874331
    
    Period of Study: 732 days (Jul
    1998-Jun2000)
    
    Location: City of Rouen, France
    Outcome: Respiratory drug sales
    
    Age Groups: 0-14,15-64, 65-74, over
    75 yr
    
    Study Design: Ecological time-series
    
    N: 106,592
    
    Statistical Analyses: Generalized
    additive model
    
    Covariates: Days of the weeks, trend,
    seasonal variations, influenza
    epidemics, meteorological variables,
    holidays
    
    Dose-response Investigated? No
    
    Statistical Package: S-plus
    
    Lags Considered: 0 to 10 days
    Pollutant: PM,0
    
    Averaging Time: Daily
    
    Mean (SD): 16.7 (13.3)
    
    Percentiles:
    
    25th: 8.00
    
    SOth(Median): 13.0
    
    75th: 20
    
    Range (Min, Max): 2.00,126
    
    Monitoring Stations: 2
    
    Copollutant (correlation):
    S02 (0.39)
    
    N02(0.61)
    PM Increment: 10 pg/m
    
    Percent increase in sales of anti-
    asthmatics and bronchodilators (Lower
    Cl, Upper Cl)
                                                                                                                6.2(2.4,10.1)
    
                                                                                                                lag 10 days
    
                                                                                                                Percent increase in sales of cough and
                                                                                                                cold preparation for children under 15 yr
                                                                                                                of age (Lower Cl, Upper Cl)
                                                                                                                9.2(5.9,12.6)
    
                                                                                                                10 days
    December 2009
                                    E-162
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Preutthipan et al. (2004,
    0555981
    
    Period of Study: 31 days (school
    days) from Jan-Feb 1999
    
    Location: Mae Pra Fatima School,
    central Bangkok, Thailand
    Outcome: Decreases in peak
    expiratory flow rates (PEFR),
    respiratory symptoms including wheeze,
    shortness of breath, runny/stuffed nose,
    sneezing, cough, phlegm, and sore
    throat
    
    Age Groups: Third to ninth grade
    
    Study Design: Time- Series
    
    N: 133 children (93 asthmatics, 40
    nonasthmatics)
    
    Statistical Analyses: For continuous
    data, an unpaired t-test or Mann-
    Whitney U test was used. For
    categorical data, the chi-square test or
    Fisher's exact test  was used. One-way
    analysis of covariance (ANCOVA) was
    used to compare avg daily reported
    respiratory symptoms, diurnal PEFR
    variability, and the  prevalence of PEFR
    decrements between groups of days.
    
    Covariates: Age, sex, weight, height,
    parents smoking, person smoking in
    home, daily number of household
    cigarettes, air-conditioned bedroom,
    fuel used for cooking (charcoal, gas),
    distance from home to main road
    
    Dose-response Investigated? No
    
    Lags Considered: Up to 5 days
    Pollutant: PM,0
    
    Averaging Time: Daily
    
    Mean (SD): 111.0 (39)
    
    Range (Min, Max): 46, 201
    
    Monitoring Stations: 1
    
    Copollutant:
    
    S02
    
    CO
    
    03
    PM Increment: Authors classified
    exposure according to High and Low
    PM10 days:
    High = >120|jg/m3
    Low = <120|jg/m3
    Daily reported respiratory symptoms
    and diurnal PEFR variability as
    classified by concurrent days with high
    vs.. lowPM10
    Mean % reporting (SEM)
    Asthmatics: High PM10
    Wheeze/shortness of breath =
    21.3(1.4)
    Runny/stuffed nose or sneezing =
    42.3(1.8)
    Cough = 59.9 (1.9)
    Phlegm = 60.5 (2.3)
    Sore throat = 23.7 (1.5)
    Any respiratory symptoms = 72.2 (3.2)
    Diurnal PEFR variability = 3.0 (0.4)
    Asthmatics: Low PMi0
    Wheeze/shortness of breath =
    19.3(1.3)
    Runny/stuffed nose or sneezing =
    35.8(1.6)
    Cough = 59.1  (1.6)
    Phlegm = 58.6 (2.0)
    Sore throat = 21.0(1.4)
    Any respiratory symptoms = 63.8 (2.8)
    Diurnal PEFR variability = 2.8 (0.3)
    Nonasthmatics: High PMi0
    Wheeze/shortness of breath =
    11.7(1.4)
    Runny/stuffed nose or sneezing =
    40.9 (2.5)
    Cough = 50.4 (2.6)
    Phlegm = 50.2 (2.5)
    Sore throat = 27.1 (1.7)
    Any respiratory symptoms = 67.8 (3.7)
    Diurnal PEFR variability = 2.4 (0.4)
    Nonasthmatics: Low PM10
    Wheeze/shortness of breath = 9.3 (1.2)
    Runny/stuffed nose or sneezing =
    33.1 (2.2)
    Cough = 54.0 (2.2)
    Phlegm = 49.9 (2.2)
    Sore throat = 23.9 (1.5)
    Any respiratory symptoms = 56.4 (3.2)
    Diurnal PEFR variability = 2.1 (0.4)
    Notes: None of the daily reported
    respiratory symptoms had significant
    direct correlations with daily PM10
    levels, according to the authors.
    December 2009
                                    E-163
    

    -------
                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Rabinovitch et al. (2004,
    0967531
    
    Periods of Study: Nov 1999-Mar 2000
    
    Nov 2000-Mar 2001
    
    Nov 2001-Mar 2002
    
    Location: Denver, Colorado
    Outcome: Respiratory symptoms,
    Asthma symptoms (cough and
    wheeze),  Upper respiratory symptoms
    
    Study Design: Time-series panel
    
    Statistical Analyses: Logistic linear
    regression
    
    Age Groups: 6-12
    Pollutants: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): 28.1 (13.2)
    
    Range (Min, Max):
    
    (6.0, 102.0)
    
    Copollutant:
    
    CO
    
    NO,
                                                                                                              Increment: 1 pg/rrf
    AM:-0.010 (0.008)
    PM:-0.011 (0.010)
    Odds Ratio (Lower Cl, Upper Cl)
    Lag
    1.016(0.911,1.133)
    0-3 avg.
    OR for respiratory symptoms and PMi0
    exposure for children age 6-12
    Asthma exacerbation:
    1.00(0.75, 1.25) 0-3 avg
    Medication: 0.85 (0.75, 0.95) 0-3 avg
    Previous night's symptoms:
    1.10(1.00,1.20) 0-3 avg
    Current day's symptoms:
    1.00(0.90,1.10) 0-3 avg
    % Increase (Lower Cl, Upper Cl)
    Lag
    % Increase in FEV, or PEF and PM,0
    exposure for children age 6-12
    AM FEV,:-0.01 (-0.02, 0.01) 0-3 avg
    PMFEV,:-0.02 (-0.03, 0.02) 0-3 avg
    AM PEF: -0.025 (-0.035, 0.02) 0-3 avg
    PM PEF: 0.00 (-0.03, 0.03) 0-3 avg.
    Reference: Renzetti et al. (2009,
    1998341
    Period of Study: Jun 2006-Jul 2006
    
    Location: Pescara and Ovindoli, Italy
    Outcome: Airway inflammation and
    function
    
    Study Design: Panel
    
    Covariates: NR
    
    Statistical Analysis: Student T-test,
    Pearson's correlation coefficients
    
    Statistical Package: StatView
    
    Age Groups: Children, mean age
    9.9 yr
    Pollutant: PM10
    
    Averaging Time: Daily
    
    Mean (SD) Unit:
    
    Urban: 56.9 ±13.1 pg/m3
    
    Rural: 13.8 + 5.6 pg/m3
    
    Copollutant (correlation): NR
    All results are presented in Fig format.
    December 2009
                                    E-164
    

    -------
                  Study
                                               Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Rojas-Martinez et al. (2007,  Outcome: Lung function: FEVi, FVC,
                                        FEF25.75%
    0910641
    
    Period of Study: 1996-1999
    
    Location: Mexico City, Mexico
                                        Age Groups: Children 8 yr old at time
                                        of cohort recruitment
    
                                        Study Design: School-based "dynamic'
                                        cohort study
    
                                        N: 3170 children
    
                                        14,545 observations
    
                                        Statistical Analyses: Three-level
                                        generalized linear mixed models with
                                        unstructured variance-covariance matrix
    
                                        Covariates: Age, body mass index,
                                        height, height by age, weekday spent
                                        outdoors, environmental tobacco
                                        smoke, previous-day mean air pollutant
                                        concentration, time since first test
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: SAS
    
                                        Lags Considered: 0-1 days
    Pollutant: PM,0
    
    Averaging Time: 24 h, 6 mo
    Mean (SD): 24-h averaging
    Tlalnepantla: 66.7 (35.6)
    Xalostoc: 96.7 (49.4)
    Merced: 79.3 (40.8)
    Pedregal:53.4(31.9)
    Cerrode la Estrella: 69.6 (35.3)
    6-mo averaging
    Mean: 75.6
    Percentiles: 6-mo averaging
    25th: 55.8
    SOth(Median): 67.5
    75th: 92.2
    Monitoring Stations:  5 sites for PIvl-
    10 for other pollutants
    
    Copollutant:
    03
    
    N02
    PM Increment: IQR
    
    PM10, 6-LC: 36.4
    GIRLS
    One-pollutant model
    FVC:-39 [-47:-31]
    FEV: -29 [-36: -21]
    FEF25.75%:-17[-36:1]
    FEV,/FVC: 0.12 [0.07: 0.17]
    Two-pollutant model
    PM10, 6-LC&03
    FVC: -30 [-39: -22]
    FEV:-24 [-31:-16]
    FEF25.75%:-9[-26:9]
    FEV,/FVC: 0.10 [0.06: 0.15]
    PM10, 6-LCSN02
    FVC:-21 [-30:-13]
    FEV:-17 [-25:-8]
    FEF25.75%: -23 [-43: -4]
    FEV,/FVC: 0.07 [0.02: 0.13]
    Multipollutant model
    PM10, 6-LC, 03, & N02
    FVC: -14 [-23: -5]
    FEV:-11 [-20:-3]
    FEF25-75%: -7 [-27: 12]
    FEV,/FVC: 0.08 [0.03: 0.13]
    
    BOYS
    One-pollutant model
    FVC:-33 [-41:-25]
    FEV:-27 [-34:-19]
    FEF25.75%:-18[-34:-2]
    FEV,/FVC: 0.04 [-0.01: 0.09]
    Two-pollutant model
    PM10, 6-LC&03
    FVC:-28 [-36:-19]
    FEV:-22 [-30:-15]
    FEF25.75%:-10[-27:7]
    FEV,/FVC: 0.04 [-0.01: 0.09]
    PM10, 6-LCSN02
    FVC: -16 [-26: -7]
    FEV:-19 [-27:-10]
    FEF25.75%: -26 [-44: -9]
    FEV,/FVC: 0.005 [-0.06: 0.05]
    Multipollutant model
    PM10, 6-LC, 03, & N02
    FVC: -12 [-22: -3]
    FEV:-15 [-23:-6]
    FEF25.75%:-12[-30:6]
    FEV,/FVC: -0.002 [-0.06: 0.05]
    Long-term exposure to 03, PM10, and
    N02 is associated with decrements in
    FVC and FEVi growth in Mexico City
    schoolchildren. In  a multipollutant
    model, PM,o (-12%), 03 (-9%), and N02
    (-41%) each contribute independently
    and statistically significantly to
    diminished FVC growth. For FEV,,
    however, the multipollutant model
    indicates that only PM10 (-15%) and
    N02 (-25%) each contribute
    independently and statistically
    significantly to diminished FEVi  growth.
    December 2009
                                                                        E-165
    

    -------
                  Study
                                                Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Location: Hamilton, Canada
    Reference: Sahsuvaroglu et al. (2009,   Outcome: Asthma symptoms
    1909831
                                        Study Design: Panel
    Period of Study: 1994-1995
                                        Covariates: Neighborhood income,
                                        dwelling value, state of housing,
                                        deprivation index, smoking
    
                                        Statistical Analysis: Logistic
                                        regressions
    
                                        Statistical Package: SPSS
    
                                        N:6388
    
                                        Age Groups:
                                        Children in  grades 1  and 8
    Pollutant: PM,0
    
    Averaging Time: 3-yr avg
    Avg:
    All Subjects: 20.90 pg/m3
    Boys: 20.88 pg/m3
    Girls: 20.92 pg/m3
    
    Range:
    All Subjects: 26.98
    Boys: 26.98
    Girls: 20.10
    
    Copollutant (correlation):
    NOxTheissen: 0.083
    SOJheissen: -0.021
    03Theissen: -0.251
    N02Kriged:0.126
    N02LUR: 0.072
    Increment: NR
    Odds Ratio (96%CI) for copollutant
    model PMIOSpline and N02LUR
    All Girls: 1.063 (0.969-1.666)
    Older Girls: 1.058 (0.918-1.219)
    
    Odds Ratio (96%CI) for copollutant
    model PMIOSpline and N02LUR,
    S02Theissen and OSTheissen
    All Girls: 1.045 (0.943-1.158)
    Older Girls: 1.044 (0.891-1.225)
    
    Regression coefficients (96%CI)
    between non-allergic asthma and
    PMIOSpline exposure
    All Children: 1.043 (0.996-1.092)
    Younger Children: 1.011 (0.929-1.100)
    Older Children: 1.073 (1.013-1.136)
    All Girls: 1.069 (0.999-1.144)
    All Boys:  1.024 (0.962-1.091)
    Younger Girls: 1.065 (0.943-1.203)
    Younger Boys: 0.962 (0.853-1.085)
    Older Girls: 1.072 (0.984-1.169)
    Older Boys: 1.075 (0.995-1.160)
    Reference: Sanchez-Carrillo et al.
    (2003, 0984281
    
    Period of Study: 1996-1997
    
    Location: metropolitan Mexico City,
    Mexico
                                        Outcome: Upper respiratory symptom
                                        indicator (wet cough, sore throat,
                                        hoarseness, nose dryness,  and head
                                        cold); Lower respiratory symptom
                                        indicator (dry cough, lack of air, and
                                        chest sounds); and Ocular symptom
                                        indicator (eye irritation, eye itch, eye
                                        burning, teary eyes, red eyes, and eye
                                        infection)
    
                                        Age Groups: All ages
    
                                        Study Design: Cohort
    
                                        N: 151,418 interviews
    
                                        Statistical Analyses: Logistic
                                        regression models
    
                                        Covariates: Sex, age, education,
                                        cigarette smoking, season,  emergency
                                        episode mass media report,
                                        temperature, and relative humidity
    
                                        Dose-response Investigated? Yes
    
                                        Statistical Package: NR
    
                                        Lags Considered: 1
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Mean (SD):
    Northeast: 132 (52)
    Northwest: 87 (46)
    Central: 85 (37)
    Southeast: 79 (35)
    Southwest: 55 (28)
    
    Range (Min, Max):
    Northeast: (34-269)
    Northwest: (10-275)
    Central: (9-319)
    Southeast: (14-225)
    Southwest: (12-264)
    Monitoring Stations: Up to 32
    Copollutant (correlation):
    03:r = 0.067
    03 8: 00-18: 00 h:r = 0.075
    S02:r = 0.265
    N02:r = 0.265
    Effect Estimate [Lower Cl, Upper Cl]:
    PMio quartiles:
    10.04-52.62 (ref) 52.63-73.58
    Upper respiratory indicator:
    1.02(0.99-1.06)
    Lower respiratory indicator:
    1.04(0.99-1.09)
    Ocular indicator:
    0.99(0.95-1.03)73.59-101.91
    Upper respiratory indicator:
    1.07(1.03-1.10)
    Lower respiratory indicator:
    1.09(1.04-1.14)
    Ocular indicator:
    0.89(0.86-0.92)101.92-318.80
    Upper respiratory indicator:
    0.93 (0.90-0.97)
    Lower respiratory indicator:
    1.03(0.98-1.08)
    Ocular indicator: 0.84 (0.81-0.87)
    Northeast - 2nd quartile
    Upper respiratory indicator:
    0.354(0.112-1.222)
    Lower respiratory indicator:
    0.215(0.040-1.160)
    Ocular indicator: 1.080 (0.915-1.274)
    3rd quartile
    Upper respiratory indicator:
    0.118(0.039-0.356)
    Lower respiratory indicator:
    0.126(0.023-0.690)
    Ocular indicator: 1.228 (0.720-2.095)
    4th quartile
    Upper respiratory indicator:
    0.095 (0.034-0.267)
    Lower respiratory indicator:
    0.119(0.026-0.549)
    Ocular indicator: 0.878 (0.619-1.246)
    Northwest - 2nd quartile
    Upper respiratory indicator:
    0.990(0.898-1.090)
    Lower respiratory indicator:
    1.246(1.087-1.429)
    Ocular indicator: 1.218 (0.808-1.834)
    3rd quartile
    Upper respiratory indicator:
    1.133(0.974-1.317)
    Lower respiratory indicator:
    1.202(1.044-1.385)
    Ocular indicator:
    0.345(0.125-0.951)
    4th quartile
    Upper respiratory indicator:	
    December 2009
                                                                         E-166
    

    -------
                   Study                        Design & Methods                 Concentrations!              Effect Estimates (95% Cl)
    
                                                                                                                     1.019(0.904-1.149)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     1.344(1.137-1.589)
                                                                                                                     Ocular indicator: 1.949 (1.416-2.683)
                                                                                                                     Central - 2nd quartile
                                                                                                                     Upper respiratory indicator: 1.088
                                                                                                                     (1.002-1.183)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     1.046(0.930-1.176)
                                                                                                                     Ocular indicator: 1.220 (1.115-1.335)
                                                                                                                     3rd quartile
                                                                                                                     Upper respiratory indicator:
                                                                                                                     1.054(0.977-1.137)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     1.055(0.948-1.175)
                                                                                                                     Ocular indicator: 1.049 (0.965-1.142)
                                                                                                                     4th quartile
                                                                                                                     Upper respiratory indicator:
                                                                                                                     0.899 (0.826-0.979)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     0.952(0.845-1.073)
                                                                                                                     Ocular indicator: 0.875 (0.796-0.963)
                                                                                                                     Southeast - 2nd quartile
                                                                                                                     Upper respiratory indicator:
                                                                                                                     0.778(0.575-1.052)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     1.047(0.916-1.196)
                                                                                                                     Ocular indicator: 0.460 (0.299-0.708)
                                                                                                                     3rd quartile
                                                                                                                     Upper respiratory indicator:
                                                                                                                     1.297(1.127-1.491)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     1.391 (1.131-1.711)
                                                                                                                     Ocular indicator: 0.474 (0.314-0.715)
                                                                                                                     4th quartile
                                                                                                                     Upper respiratory indicator:
                                                                                                                     0.893 (0.812-0.983)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     0.937(0.818-1.073)
                                                                                                                     Ocular indicator: 0.314 (0.182-0.542)
                                                                                                                     Southwest - 2nd quartile
                                                                                                                     Upper respiratory indicator:
                                                                                                                     0.987(0.913-1.066)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     2.181 (1.177-4.040)
                                                                                                                     Ocular indicator: 1.026 (0.928-1.135)
                                                                                                                     3rd quartile
                                                                                                                     Upper respiratory indicator:
                                                                                                                     0.673(0.673-1.886)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     0.899(0.790-1.024)
                                                                                                                     Ocular indicator: 1.017 (0.862-1.200)
                                                                                                                     4th quartile
                                                                                                                     Upper respiratory indicator:
                                                                                                                     0.524(0.524-1.787)
                                                                                                                     Lower respiratory indicator:
                                                                                                                     4.346 (0.917-20.606)
                 	Ocular indicator: 0.187 (0.090-0.387)
    December 2009                                                      E-167
    

    -------
    Study
    Reference: Schildcrout et al. (2006,
    0898121
    Period of Study: Nov 1993-Sep 1995
    Location:
    Albuquerque, New Mexico
    Baltimore, Maryland
    Boston, Massachusetts
    Denver, Colorado
    San Diego, California
    Seattle, Washington
    St. Louis, Missouri
    Toronto, Ontario, Canada
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Asthma Symptoms, Rescue
    Inhaler Uses
    Age Groups: 5-12 yr
    Study Design: Meta-analysis of CAMP
    N: 990 children
    Statistical Analyses: "Working
    independence covariance structure"
    Logistic Regression
    Poisson Regression
    "GEE Procedure"
    Covariates: Season, age, race-
    ethnicity, annual family income, day of
    the week
    Dose-response Investigated?
    Statistical Package: SAS 8.2
    R
    
    Lags Considered: 0 day lag, 1 day lag,
    2 day lag, 3-day moving sum
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Concentrations!
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Seattle: Daily
    Albuquerque: Daily
    Baltimore: 50% of study days measured
    Boston: 23% of study days measured
    Denver: 37% of study days measured
    San Diego: 24% of study days
    measured
    St. Louis: 19% of study days measured
    Toronto: 47% of study days measured
    Percentiles:
    10th: 6.8-14.0
    25th: 12.0-22.4
    SOth(Median): 17.7-32.4
    75th: 26.2-42.7
    90th: 32.5-53.9
    Monitoring Stations: 1-12
    Copollutant (correlation):
    N02r = 0.26-0.64
    S02r = 0.31-0.65
    03r = 0.03-0.73
    CO r = 0.24-0.88
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 25 pg/m3
    One-pollutant model
    Asthma Symptoms:
    1.02 0.94, 1.11 0
    1.01 0.97, 1.06 1
    1.02 0.98, 1.07 2
    1.01 0.98, 1.05
    3-day moving sum
    Rescue Inhaler Uses:
    [0 97 1 05 0
    [0.97, 1.05 1
    1.00 [0.97, 1.03] 2
    1.01 [0.98, 1.03]
    3-day moving sum
    Two-pollutant model
    Asthma Symptoms:
    CO-PM,o
    1.08 1.01,1.15 0
    1.06 0.99, 1.14 1
    1.08 1.02, 1.14 2
    1.05 1.01, 1.08
    3-day moving sum
    N02~ PM10
    1 06 099 1 13 0
    1.04 0.97 1.11 1
    1.08 1.02, 1.15 2
    1.04 1.00, 1.07;
    3-day moving sum
    S02-PM10
    1.05 0.98, 1.13 0
    1.04 0.96, 1.14 1
    1.05 0.98, 1.12 2
    1.04 0.99, 1.08;
    3-day moving sum
    Rescue Inhaler Uses:
    CO-PM,o
    1.06 0.99, 1.13 0
    1.05 0.99, 1.11 1;
    1.05 1.01, 1.09 2
    1.03 1.00, 1.07;
    3-day moving sum
    N02" PM10
    1.03 0.97, 1.08 0
    1.03 0.98, 1.08 1
    1.04 1.00, 1.09 2
    1.02 1.00, 1.05
    3-day moving sum
    S02-PM10
    1.01 0.95, 1.07 0
    1.02 0.97, 1.07 1
    1.03 0.98, 1.09 2
    1.02 0.98, 1.05;
    3-day moving sum
    All units expressed in pg/m  unless otherwise specified.
    December 2009
    E-168
    

    -------
    Table E-10.   Short-term exposure - respiratory morbidity outcomes - PMio25.
            Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
    Reference: Aekplakorn et al.
    (2003, 089908)
    Period of Study: 107 days,
    Oct1997-Jan1998
    Location: Mae Mo district,
    Lampang Province, north
    Thailand
    Outcome: Upper respiratory
    symptoms, lower respiratory
    symptoms, cough
    Age Groups: 6-1 4 yr
    Study Design: Logistic regression
    N: 98 asthmatic school children
    Statistical Analyses: Generalized
    Pollutant: PM10.2.5
    Averaging Time: Daily
    Mean (SD): NR
    Range (Min, Max): NR
    Monitoring Stations: 3
    Copollutant: PM10, S02
    PM Increment: 10fjg/m°
    Odds Ratios [Lower Cl, Upper Cl] lag:
    Asthmatics:
    URS: 1.04 (0.93, 1.17) lag 0
    LRS: 1.09 (0.95, 1.26) lag 0
    Cough: 1.08 (0.96, 1.21) lag 0
    Non-Asthmatics:
    i IDC' ^ CK /n on -i ^\ i-^n n
                           Estimating Equations, stratified
                           analysis, PROCGENMOD
    
                           Covariates: Temperature and relative
                           humidity
    
                           Season: Winter
    
                           Dose-response Investigated? No
    
                           Statistical Package: SASv 8.1
                                                    URS: 1.05 (0.99,1.19) lag 0
                                                    LRS: 0.90 (0.72,1.11) lag 0
                                                    Cough: 0.95 (0.81,1.11) lag 0
    December 2009
                                E-169
    

    -------
              Study
           Design & Methods
         Concentrations1
               Effect Estimates (95% Cl)
    Reference: Bourotte et al.
    (2007,1500401
    
    Period of Study:
    May 2002-Jul 2002
    
    Location: Sao Paulo, Brazil
    Outcome: Peak expiratory flow (PEF)  Pollutant: PM:
    
    Age Groups: Avg age 39.8 ± 12.3 yr
    
    Study Design: Cross-sectional
    
    N: 33 patients
                                Statistical Analyses: Linear mixed-
                                effects model
    
                                Covariates: Gender, Age, BMI, Air
                                Pollutants, Ambient temperature,
                                Relative Humidity
    
                                Season: Winter
    
                                Dose-response Investigated? No
    
                                Statistical Package: S-plus
    
                                Lags Considered: 2-day lag, 3-day
                                lag
    Averaging Time: 24 h
    
    Mean(SD):21.7(12.9)|jg/m3
    
    Range (Min, Max): (4.13, 62.0)
    Components:
    Na*
    K*
    Mg2*
    Ca2*
    Finf
    Cl-
    N03:
    S042"
    Monitoring Stations: 1
    PM Increment: NR
    
    Effect [Lower Cl, Upper Cl] lag:
    
    Morning PEF
    Na* concurrent day = -0.454 (-1.605, 0.697)
    Na* 2-day lag  = -0.907 (-2.288, 0.474)
    Na* 3-day lag  = -1.361 (-2.972, 0.251)
    K* concurrent  day = 1.685 (-0.492, 3.862)
    K* 2-day lag = 1.838 (-1.272, 4.984)
    K* 3-day lag = 2.604 (-0.812, 6.025)
    Mg2* concurrent day = 2.265* (-0.427, 4.956)
    Mg2* 2-day lag = 1.271 (-1.869,4.410)
    Mg2* 3-day lag = 0.939 (-2.425, 4.303)
    Ca2* concurrent day = 5.491* (2.558, 8.424)
    Ca2* 2-day lag = 6.358* (2.251,10.465)
    Ca2* 3-day lag = 6.069 (1.962,10.176)
    Finf concurrent day = 1.572 (-0.792, 3.935)
    Finf 2-day lag = 1.630 (-1.679, 4.939)
    Finf 3-day lag = 2.736* (-1.754, 7.226)
    Cl" concurrent day = -0.951  (-2.238, 0.336)
    Cl" 2-day lag = -1.871 (-3.242 to -0.4997)
    Cf 3-day lag = -2.286* (-3.934 to -0.638)\
    N03" concurrent day = 4.195* (-0.063, 8.452)
    N03" 2-day  lag = 6.292* (2.034, 10.55)
    N03" 3-day  lag = 7.341* (3.083,11.60)
    S042" concurrent day = 3.528 (-0.053, 7.110)
    S042" 2-day lag = 4.411* (0.829, 7.991)|
    S042" 3-day lag = 6.175* (2.593, 9.756)
    
    Evening PEF
    Na* concurrent day = -0.680 (-1.831, 0.471)
    Na* 2-day lag  = -1.90 (-3.316 to -0.494)
    Na* 3-day lag  = -2.336* (-3.878 to -0.794)
    K* concurrent  day = 0.613 (-1.564, 2.790)
    K* 2-day lag = 0.613 (-2.497, 3.723)
    K* 3-day lag = 0.000 (-3.421, 3.421)|
    Mg2+ concurrent day = -0.718 (-3.522, 2.085)
    Mg2+2-day lag = -1.933 (-5.073,1.206)
    Mg2+ 3-day lag = -3.591  (-7.056 to -0.126)
    Ca2+ concurrent day = 2.312* (-1.208, 5.832)
    Ca2+2-day  lag = 2.023 (-2.084, 6.130)
    Ca2+ 3-day  lag = 0.578 (-3.530, 4.685)
    Fin, concurrent day = -1.281  (-3.644,1.083)
    Fin, 2-day lag = -2.503 (-5.930, 0.924)
    Fin, 3-day lag = -4.540 (-9.149, 0.068)
    Cf concurrent day = -0.317 (-1.604, 0.970)
    Cf 2-day lag = -1.268 (-2.556, 0.019)
    Cl" 3-day lag = -1.902 (-3.589 to -0.216)
    N03"concurrent day = 3.146 (-1.112, 7.404)
    N03" 2-day  lag = 3.146 (-1.112, 7.404)
    N03" 3-day  lag = 1.049 (-3.209, 5.306)
    S042" concurrent day = 1.764 (-1.817, 5.346)
    S042" 2-day lag = 2.646 (-0.935, 6.228)
    S042" 3-day lag = 1.764 (-1.817, 5.346)
    Reference: Ebelt et al. (2005,
    0569071
    
    Period of Study: Summer of
    1998
    
    Location: Vancouver,
    Canada
    Outcome: Spirometry
    
    Age Groups: Range from 54-86 yr
    
    Mean age= 74 yr
    
    Study Design: Extended analysis of a
    repeated-measures panel study
    
    N: 16 persons with COPD
    
    Statistical Analyses: Earlier analysis
    expanded by developing mixed-effect
    regression models and by evaluating
    additional exposure indicators
    
    Dose-response Investigated? No
    
    Statistical Package: SASV8
    Pollutant: PM10.25
    
    Averaging Time: 24 h
    Mean (SD):
    Ambient PMi0.25: 5.6 (3.0)
    Exposure to ambient PMio-2 5:
    2.4(1.7)
    Range (Min, Max):
    Ambient PMio.25: (-1.2-11.9)
    Exposure to ambient
    PMio.25: (-0.4-7.2)
    Monitoring Stations: 5
    Copollutant (correlation):
    Ambient PM,0: r= 0.69
    Ambient PM25:r= 0.15
    Nonsulfate Ambient
    PM25:r=0.14
    Exposure to Ambient
    PM10.25: r= 0.73	
    PM Increment: Ambient PM10.25: 4.5 (IQR)
    
    Exposure to ambient PM10.2 5: 2.4 (IQR)
    
    Notes: Effect estimates are presented in Fig 2 and
    Electronic Appendix Table 1 (only available with electronic
    version of article) and not provided quantitatively
    elsewhere.
    December 2009
                                             E-170
    

    -------
    Study
    Reference: Lagorio et
    al.(2006, 089800)
    
    Period of Study: May
    1999-June 1999 and Nov
    1999-Dec1999
    Location: Rome, Italy
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Laurent et al.
    (2008, 1566721
    Period of Study: Dec
    2003-Dec 2004
    Location: Strasbourg, France
    
    
    
    Reference: Tang et al. (2007,
    0912691
    Period of Study:
    Dec 2003-Feb 2005
    Location: Sin-Chung City,
    Taipei County, Taiwan
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Lung function of subjects
    (FVC and FEV,) with COPD, Asthma
    Age Groups: COPD 50-80 yr
    Asthma 1 8-64 yr
    Study Design: Time series
    N: COPD N = 11; Asthma N = 11
    Statistical Analyses: Non-parametric
    Spearman correlation
    GEE
    
    Covariates:
    COPD: daily mean temperature,
    season variable (spring or winter),
    relative humidity, day of week
    
    Asthma: season variable, temperature,
    humidity, and D-2-agonist use
    Season: Spring and winter
    Dose-response Investigated? Yes
    Statistical Package: STATA
    
    Lags Considered: 1-3 days
    
    
    Outcome: Sales of short acting |3-
    agonists
    Study Design: Case-crossover
    Covariates: NR
    
    Statistical Analysis: Conditional
    logistic regression
    Age Groups: 0-39 yr
    Outcome: Peak expiratory flow rate
    (PEFR) of asthmatic children
    Age Groups: 6-1 2 yr
    
    Study Design: Panel study
    N: 30 children
    Statistical Analyses:
    Linear mixed-effect models were used
    to estimate the effect of PM exposure
    on PEFR
    Covariates: Gender, age, BMI, history
    of respiratory or atopic disease in
    family, SHS, acute asthmatic
    exacerbation in past 12 mo, ambient
    temperature and relative humidity,
    presence of indoor pollutants, and
    presence of outdoor pollutants,
    Dose-response Investigated? yes
    Statistical Package: S-Plus2000
    Lags Considered: 0-2
    Concentrations1
    PM Size: PM10.2.5
    Averaging Time: 24 h
    Mean (SD):
    Overall: 15.6 (7.2)
    Spring: 18.7 (7.4)
    Winter: 12.3 (5.4)
    Range (Min, Max): (3.4, 39.6)
    PM Component:
    Cd: 0.46+0.40 ng/m3
    Cr:1.9±1.7ng/rr?
    Fe: 283+167 ng/m3
    Ni: 4.8+6.5 ng/m
    Pb: 30.6+19.0 ng/m3
    Pt: 5.0+8.6 pg/rr?
    V: 1.8+1. 4 ng/m3
    Zn: 45.8+33.1 ng/m3
    
    Monitoring Stations: Two fixed
    sites: (Villa Ada and Istituto
    superior di Sanita)
    Copollutant (correlation):
    N02r = 0.51
    03r = 0.31
    CO r = -0.09
    S02r = -0.16
    PM10r = 0.61
    PM25r = 0.34
    Pollutant: PM,0
    Averaging Time: NR
    Mean (SD) Unit: 20.8 (10.2)
    pg/m3
    
    Range (Min, Max): NR
    Copollutant (correlation): N02,
    03, correlations NR
    Pollutant: PMi0.25
    Averaging Time: 1 h
    
    Mean (SD):
    Personal: 17.8 (19.6)
    Ambient: 17.0 (10.6)
    Range (Min, Max):
    
    Personal: 0.3-195.7
    Ambient: 0.1-80.2
    Monitoring Stations: 1
    
    
    
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 1 pg/m3
    They observed no statistically significant effect of PM10.2.5
    on FVC and FEV, on any of the panels (COPD, Asthma).
    P Coefficient (SE)
    COPD
    FVC(%)
    24 h -1.32 (1.06)1
    48-h -1.46 (1.31)
    72-h -1.38 (1.53)
    FEVi(%)
    24 h -0.59 (0.95)
    48-h -1.01 (1.19)
    72-h -0.90 (1.42)
    
    Asthma
    FVC(%)
    24 h -0.1 7 (0.75)
    48-h -0.36 (0.91)
    72-h -0.24 (1.07)
    FEV,(%)
    24 h -0.67 (0.89)
    48-h -1.19 (1.07)
    72-h -0.51 (1.26)
    
    
    Increment: 10 pg/m3
    Percent Increase in Short Acting p-agonists sold
    Per increment increase in ambient PM10 at lags 4-7, a
    7.5% increase (95% Cl: 4-11.2%) was seen in SABA
    sales.
    
    All other results were given in Fig 1 and 2
    
    PM Increment:! 5.9 pg/m3
    RR Estimate [Lower Cl, Upper Cl]
    
    lag:
    Change in morning PEFR:
    -20.55 (-45.83, 4.73) lag 0
    -39.05 (-104.16, 26.06) lag 1
    
    -39.56 (-79.56, 0.44) lag 2
    -37.15 (-105.01, 30.7) 2-day mean
    -35.47 (-27.32, 56.38) 3-day mean
    Change in evening PEFR:
    -1.68 (-19. 13, 15.78) lag 0
    
    1.59 (-14.32, 17.5) lag 1
    0.86 (-30.84, 32.57) lag 2
    5.97 (-15.57, 27.5) 2-day mean
    29.75 (-1.69, 61. 18) 3-day mean
    December 2009
    E-171
    

    -------
              Study
           Design & Methods
         Concentrations1
               Effect Estimates (95% Cl)
    Reference: Trenga et al.,
    (2006, 1552091
    
    Period of Study: 1999-2002
    
    Location: Seattle, WA
    Outcome: Lung function: FEVi, PEF,
    MMEF (maximal midexpiratory flow
    assessed only for children)
    
    Age Groups: Adults (56-89-yr-old)
    healthy & with COPD
    
    Asthmatic children 6-13-yr-old
    
    Study Design: Adult and pediatric
    panel  study over 3 yr with 1 monitoring
    period ("session") per yr
    
    N: 57  adults (33 healthy, 24 with
    COPD) = 692 subject-days = 207
    study-days
    
    17 asthmatic children = 319 subject-
    days = 98 study-days
    
    Statistical Analyses: Mixed effects,
    longitudinal regression models, with
    the effects of pollutant decomposed
    into each subject's a) overall mean
    
    b) Difference between their session-
    specific mean and overall mean
    
    c) Difference between their daily
    values and session-specific mean
    
    Covariates: Gender, age, ventral  site
    temperature and relative humidity, CO,
    N02
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags  Considered: 0-1 days
    Pollutant: PMi0.2.5 (coarse)
    
    Averaging Time: 24 h
    Percentiles:
    Subject-specific exposure
    PM,o-PM2.5
    Outdoor
    25th: 3.3
    50th (Median): 4.7
    75th: 6.9
    
    Adults
    Outdoor
    25th: 3.3
    50th (Median): 5.0
    75th: 7.1
    Range (Min, Max):
    
    Subject-specific exposure
    
    Children
    Outdoor (0.0, 25.3)
    
    Adults
    Outdoor (0.0, 25.7)
    
    Monitoring Stations: 2
    Also subject-specific local
    outdoors (i.e., at each home),
    indoor,  and personal
    
    Copollutant (correlation):
    
    CO
    
    N02
    
    PM2.5
    PM Increment: 10|jg/m
    Adult
    Outdoor Home PM10-PM25
    FEV,
    Overall: Lag 0-27.9 [-87.5: 31.8]
    Lag 147.1 [-5.1:99.4]
    No-COPD: Lag 0 -49.2 [-22.3: 23.9]
    Lag 174.3 [6.8:141.8]
    COPD: Lag 07.3 [-84.7: 99.4]
    Lag1  11.5 [-65.4: 88.3]
    PEF
    Overall: Lag 05.3 [-5.1:15.7]
    Lag 1-2.5 [-11.6: 6.5]
    No-COPD: Lag 05.1 [-7.7:17.8]
    Lag 1-5.8 [-17.5: 5.9]
    COPD: Lag 05.7 [-10.3: 21.6]
    Lag 11.7 [-11.5:14.9]
    Pediatric
    FEV,
    Outdoor Home PMi0-PM25
    Overall
    Lag 0-7.43 [-69.41: 54.55]
    Lag 1-25.61  [-88.16: 36.94]
    NoAnti-inflam. Medication
    Lag 0-63.87  [-199.58: 71.84]
    Lag 1  -96.48  [-232.48: 39.52]
    Anti-inflam. Medication
    Lag 06.57 [-96.90:110.04]
    Lag 1-8.63 [-217.39: 200.14]
    PEF
    Outdoor Home PM10-PM25
    Overall
    Lag 04.53 [-6.60:15.67]
    Lag 1-3.35 [-14.31: 7.62]
    NoAnti-inflam. Medication
    Lag 02.05 [-22.36: 26.45]
    Lag 1-6.56 [-30.90:17.78]
    Anti-inflam. Medication
    Lag 05.15 [-7.90:18.19]
    Lag 1-2.58 [-15.35:10.19]
    MMEF
    Outdoor Home PM10-PM25
    Overall
    Lag 0-0.01 [-7.29:  7.28]
    Lag 1-2.07 [-9.25:  5.12]
    NoAnti-inflam. Medication
    Lag 0-7.14 [-23.16: 8.87]
    Lag 1-14.39  [-30.11:1.32]
    Anti-inflam. Medication
    Lag 01.76 [-6.78:10.30]
    Lag 1  0.89 [-7.56: 9.33]	
    All units expressed in pg/m unless otherwise specified.
    December 2009
                                             E-172
    

    -------
    Table E-11.   Short-term exposure - respiratory morbidity outcomes - PM2.e (including
                 components/sources).
    Study
    Reference: Adamkiewicz et al. (2004,
    0879251
    
    Period of Study: Aug-Dec 2000
    Location: Steubenville, Ohio
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Adar et al. (2007, 0986351
    Period of Study: Mar-Jun 2002
    Location: St. Louis, MO
    
    
    
    
    
    
    
    
    
    
    Reference: Aekplakorn et al. (2003,
    0899081
    Period of Study: 107 days, from Oct
    1997-Jan 1998
    Location: Mae Mo district, Lampang
    Province, north Thailand
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: FENO
    
    Age Groups: Ranged 53.5-90.6 yr
    Study Design: Prospective cohort
    N: Total of 294 breaths from 29 subjects
    
    Statistical Analyses: Fixed effect
    models, ANOVA, GLM procedure
    Covariates: Subject, week of study,
    day of the week, h of the day, ambient
    barometric pressure, temperature, and
    relative humidity
    
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: Hourly lags, 0-48 h
    
    
    
    
    
    
    Outcome: FENO
    Age Groups: 60+
    Study Design: Panel Study
    N: 44 non-smoking seniors
    Statistical Analyses: Mixed models
    containing random subject effects
    
    Covariates: Day of week, trip type,
    FENO collection device, current illness,
    use of vitamins, antihistamines, statins,
    steroids, and asthma medications,
    temperature, pollen, mold, NO
    concentration in testing room
    Statistical Package: SAS
    Lags Considered :0
    
    Outcome: Upper respiratory
    symptoms, lower respiratory symptoms,
    cough
    
    Age Groups: 6-1 4 yr old
    Study Design: Logistic regression
    N: 98 asthmatic school children
    
    Statistical Analyses: Generalized
    Estimating Equations, stratified
    analysis, PROCGENMOD
    Covariates: Temperature and relative
    humidity
    Season: Winter
    Dose-response Investigated? No
    Statistical Package: SAS v 8.1
    
    Concentrations1
    Pollutant: PM25
    
    Averaging Time: 1 h
    Mean (SD): 19.5
    Percentiles:
    O^th' 7 K
    zotn. /.D
    75th: 25.5
    Range (Min, Max): NR, 105.8
    Monitoring Stations: 1
    Averaging Time: 24 h
    Mean (SD): 19.7
    Percentiles:
    25th: 9.7
    75th: 27.4
    Range (Min, Max): NR, 57.8
    Monitoring Stations: 1
    Copollutant (correlation):
    Ambient NO
    Indoor NO
    N02
    03
    S02
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD):
    Pretrip: 14.8
    Post-trip: 16.5
    Percentiles:
    25th (pretrip): 11.2
    75th (pretrip): 20.1
    25th (post-trip: 11. 7
    75th (post-trip: 21. 6
    Monitoring Stations: 1
    Copollutant (correlation): BC
    CO
    N02
    S02
    03
    Pollutant: PM25
    Averaging Time: Daily
    
    Mean (SD):
    Sob Pad station: 24.77
    Sob Mo station: 24.89
    
    Hua Fai station: 26.27
    Range (Min, Max):
    Sob Pad: 4.52 24.77
    Sob Mo: 3.13, 24.89
    Hua Fai: 3.67, 26.27
    Monitoring Stations: 3
    Copollutant:
    PM,o
    S02
    Effect Estimates (95% Cl)
    PM Increment: 17.9 pg/m3
    
    Effect Estimate [Lower Cl, Upper Cl]:
    1-h Single pollutant models:
    0.36(0.58-2.14)
    PM Increment: 17.7
    
    Effect Estimate [Lower Cl, Upper Cl]:
    24-h ma: 1.45 (0.33-2.57)
    Multipollutant models for PM25, ambient
    NO and room NO and estimated
    change in FENO (ppb) for an IQR in
    pollutant measure
    Model! 1.95(0.47-3.43)
    Model 2 1.38 (0.26-2.51)
    Model 4 1.97 (0.48-3. 46)
    Notes: Association of FENO with PM25
    at different lags presented in Fig 1 are
    not presented quantitatively elsewhere.
    
    
    PM Increment: 9.8 pg/m3
    Effect Estimate [Lower Cl, Upper Cl]:
    Pre-trip% change: 21. 9 (6.7, 39.4)
    Post-trip % change: -4.7 (-17.1, 9.6)
    
    
    
    
    
    
    
    
    
    PM Increment: 10 pg/m3
    Odds Ratios [Lower Cl, Upper Cl]
    lag:
    Asthmatics:
    URS: 1.04 (0.99, 1.09) lag 0
    LRS: 1.05 (0.98, 1.2)lagO
    Cough: 1.05 (0.99, 1.10) lag 0
    Non-Asthmatics1
    URS: 1.03 (0.96', 1.09) lag 0
    LRS: 1. 02 (0.93, 1.10) lag 0
    Cough: 1.00 (0.93, 1.07) lag 0
    PM,0 + S02
    Asthmatics:
    URS: 1.04 (0.99, 1.10)lagO
    LRS: 1.05 (0.98, 1.10)lagO
    Cough: 1.05 (0.99, 1.11) lag 0
    Non-Asthmatics:
    URS: 1.03 (0.97, 1.09) lag 0
    LRS: 1.02 (0.93, 1.11) lag 0
    Cough: 1.00 (0.93, 1.07) lag 0
    December 2009
    E-173
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Allen et al. (2008,1562081
    
    Period of Study: 1999-2002 (additional
    PM composition data collected Dec
    2000 and May 2001)
    
    Location: Seattle, USA
    Outcome: Daily changes in exhaled
    nitric oxide (FENO) and 4 lung function
    measures, midexpiratory flow (MEF),
    peak expiratory flow (PEF), forced
    expiratory volume in 1 second (FEVi),
    and forced vital capacity (FVC)
    
    Age Groups: 6-1 Syr
    
    Study Design: Panel study
    
    N: 19 children with asthma
    
    Statistical Analyses: Linear mixed
    effects model with random intercept to
    test for within participant associations
    
    Covariates: Temperature, relative
    humidity,  BMI, age, and, in the case of
    FENO, ambient NO measured at a
    centrally located monitoring site
    
    Models also included a term for within-
    participant, within-session effects, and a
    term for participant between-session
    effects
    
    Effect modification: Decided  a priori to
    include interaction term for PM25
    exposure and inhaled corticosteroids
    Pollutant: PM25
    
    Mean (SD): 11.23 (6.48)
    
    Range (Min, Max):
    
    276-40.38
    
    25th: 6.38
    
    75th: 14.73
    
    Copollutant (correlation):
    
    Ambient LAC* r=0.83
    
    Ambient LG**r=0.84
    
    Personal PM25: r=0.34
    
    Personal LAC: r=0.54
    
    Ambient-generated PM25: r=0.87
    
    Nonambient-generated PM25: r=-0.06
    
    * LAC Light-absorbing carbon
    
    ** LG: Leroglucosan (a marker of wood
    smoke)
    Health effect estimates presented in
    graphic form (Fig 1). Summary from text
    is as follows:
    
    Personal LAC, personal PM25, and
    ambient-generated PM25were
    associated with (p < 0.05) and ambient
    PM2 5 was marginally associated
    (p=0.09) with increased FENO.  Neither
    of the ambient combustion markers
    (LAC, LG) nor nonambient-generated
    PM2 5 was associated with FENO
    changes.
    
    All of the ambient concentrations were
    associated with decrements in PEF and
    MEF while ambient-generated PM25
    was marginally associated (p < 0.10).
    
    Only ambient LG was associated with a
    decrease in FEVi and there were no
    associations between exposure metrics
    and FVC.
    Reference: Barraza-Villarreal et
    al.(2008, 1562541
    
    Period of Study: Jun 2003-Jun 2005
    
    Location: Mexico City
    Outcome: Respiratory Symptoms,
    Coughing, Wheezing, Airway
    inflammation, Asthma
    
    Study Design: Prospective cohort
    
    Statistical Analyses: Bivarate analysis
    
    Age Groups: 6-14
    Pollutant: PM25
    
    Averaging Time: Maximum 8-h avg
    
    Mean (SD) unit:
    
    28.9 (2.8)
    
    Range (Min, Max):
    
    (4.2, 102.8)
    
    Copollutants (correlation):
    
    03
    
    N02
    Increment: 17.5|jg/m
    
    % Increase (Lower Cl, Upper Cl)
                                                                                                               Asthmatic children
                                                                                                               Inflammatory Marker:
                                                                                                               FENO: 1.08 (1.01, 1.16)0
                                                                                                               IL-8:1.08 (0.98, 1.19)0
                                                                                                               ph_EBC: -0.03 (-0.09, 0.03) 0
                                                                                                               Lung Function:
                                                                                                               FEV,:-16.0(-31. Oto-0.13) 0-4 avg
                                                                                                               FVC:-23.0 (-42.0 to-5.21) 0-4 avg
                                                                                                               FEV25-75:-11.0 (-42.0, 20.3) 0-4 avg
    
                                                                                                               Nonasthmatic children
                                                                                                               Inflammatory Marker:
                                                                                                               FENO: 0.89 (0.78, 1.01)0
                                                                                                               IL-8:1.16 (1.00, 1.36)0;
                                                                                                               ph_EBC:-0.05 (-0.14, 0.04)0
                                                                                                               Lung Function:
                                                                                                               FEV,:-21.0 (-42.3, 0.38) 0-4 avg
                                                                                                               FVC:-29.0 (-52.8 to-4.35) 0-4 avg
                                                                                                               FEV25.75: -20.0 (-69.0, 29.0) 0-4 avg
    
                                                                                                               All children age 6-14
                                                                                                               Respiratory Symptom:
                                                                                                               Cough: 1.11 (1.06,1.17)
                                                                                                               Wheezing: 1.06 (0.99,1.13)	
    December 2009
                                    E-174
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Bennett et al. (2007,
    1562681
    
    Period of Study: 1992-2005
    
    Location: Melbourne, Australia
    Outcome: Adverse respiratory
    symptoms (wheeze, shortness of breath
    on waking, cough in the morning,
    phlegm in the morning, cough with
    phlegm in the morning, asthma attack)
    
    Age Groups: All ages with a mean of
    37.2 yr
    
    Study Design: Cohort study
    
    N: 1446 persons
    
    Statistical Analyses: Logistic
    regression models
    
    Covariates: Age, gender, current
    smoking status, medication use (IS2-
    agonist and inhaled steroid), atopy
    
    Dose-response Investigated? No
    
    Statistical Package: STATA statistical
    software, version 9 (Statcorp, 2005)
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD): 6.8
    
    Range (Min, Max): (1.8-73.3)
    
    Monitoring Stations: 1
    PM Increment: 1 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Within-person (longitudinal effects)
    Wheeze: OR=1.08 (0.79-1.48)
    SOB on waking: OR=1.34 (0.84-2.16)
    Cough in the morning:
    OR=0.74 (0.47-1.15)
    Phlegm in the morning:
    OR=1.55 (0.95-2.53)
    Cough w/phlegm morning:
    OR=1.28 (0.70-2.33)
    Asthma attack: OR=0.91 (0.55-1.49)
    Between-person (cross-sectional)
    effects
    Wheeze: OR=1.32 (0.82-2.10)
    SOB on waking: OR=1.29 (0.46-3.60)
    Cough in the morning:
    OR=0.21 (0.07-0.62)
    Phlegm in the morning:
    OR=0.49(0.16-1.44)
    Cough w/phlegm morning:
    OR=0.28 (0.08-0.97)
    Asthma attack: OR=0.52 (0.17-1.59)
    December 2009
                                    E-175
    

    -------
                  Study
           Design & Methods
             Concentrations1
       Effect Estimates (95%  Cl)
    Reference: Bourotte et al. (2007,
    1500401
    
    Period of Study: May 2002-Jul 2002
    
    Location: Sao Paulo, Brazil
    Outcome: Peak expiratory flow (PEF)
    
    Age Groups: Avg age 39.8 ± 12.3 yr
    
    Study Design: Cross-sectional
    
    N: 33 patients
    
    Statistical Analyses:
    Linear mixed-effects model
    
    Covariates: Gender, Age, BMI, Air
    Pollutants, Ambient temperature,
    Relative Humidity
    
    Season: Winter
    
    Dose-response Investigated? No
    
    Statistical Package: S-plus
    
    Lags Considered: 2-day lag, 3-day lag
    Pollutant: PM25 (Fine)
    
    Averaging Time: 24 h
    
    Mean(SD):11.9(5.12)
    
    Range (Min, Max):
    
    (2.82, 26.6)
    
    Components:
    K*
    Mg2*
    Ca2*
    Fin,
    Cl"
    N03:
    S042"
    Monitoring Stations: 1
    PM Increment: NR
    
    Effect [Lower Cl, Upper Cl] lag:
    Morning PEF
    Na* concurrent day =
    -0.409 (-2.485, 1.667)
    Na* 2-day lag = -0.818 (-4.139, 2.503)
    Na* 3-day lag = -0.205 (-4.356, 3.974)
    K* concurrent day =
    -0.211 (-2.778, 2.357)
    K* 2-day lag = -0.843 (-4.695, 3.008)
    K* 3-day lag = 0.843 (-4.292, 5.978)
    Mg2* concurrent day =
    -1.750 (-5.302, 1.802)
    Mg2* 2-day lag = -5.016 (-10.79, 0.762
    Mg2* 3-day lag = -3.850 (-10.15, 2.449
    Ca2* concurrent day =
    3.192*(-0.599, 6.943)
    Ca2* 2-day lag = 5.880 (1.105,10.65)
    Ca2* 3-day lag = 7.560* (2.103,13.02)
    Fjnf concurrent day =
    2.218*(-0.033,4.470)
    Finf 2-day lag = 3.697* (1.446, 5.949)
    Fin, 3-day lag =4.067* (1.065, 7.069)
    Cl" concurrent day =
    -1.010 (-3.469, 1.450)
    Cl" 2-day lag = -1.615
                                                                                                                 Cl" 3-day lag = -1.615
                                                                                                 -5.714, 2.483
                                                                                                 -6.534, 3.303
                                                                                                                 N03 concurrent day =
                                                                                                                 3.144(0.409,5.878)
                                                                                                                 N03" 2-day lag = 3.593 (0.858, 6.328)
                                                                                                                 N03" 3-day lag = 4.491 (1.756, 7.226)
                                                                                                                 S042 concurrent day =
                                                                                                                 2.210 (-0.032, 4.272)
                                                                                                                 S042" 2-day lag = 3.180 (1.028, 5.332)
                                                                                                                 S042" 3-day lag = 3.180 (1.028, 5.332)
                                                                                                                 Evening PEF
                                                                                                                 Na* concurrent day =
                                                                                                                 -1.636 (-3.712, 0.440)
                                                                                                                 Na* 2-day lag = -0.205 (-3.256, 3.117)
                                                                                                                 Na* 3-day lag = -1.023 (-5.174, 3.129)
                                                                                                                 K* concurrent day =
                                                                                                                 -1.897 (-4.465, 0.670)
                                                                                                                 K* 2-day lag = -1.686 (-5.966, 2.592)
                                                                                                                 K* 3-day lag = -1.054 (-6.189, 4.081)
                                                                                                                 Mg2* concurrent day =
                                                                                                                 -2.753 (-6.400, 0.894)
                                                                                                                 Mg2* 2-day lag = -2.567 (-8.534, 3.401)
                                                                                                                 Mg2* 3-day lag = -4.876 (-11.36,1.612)
                                                                                                                 Ca2* concurrent day =
                                                                                                                 2.184 (-1.567, 5.935)
                                                                                                                 Ca2*2-day lag = 5.040 (0.265, 9.815)
                                                                                                                 Ca2* 3-day lag = 5.040 (-0.417,10.50)
                                                                                                                 FM f concurrent day =
                                                                                                                 1.479 (-0.773, 3.730)
                                                                                                                 Fin, 2-day lag = 1.819 (-0.403, 4.100)
                                                                                                                 Fn, 3-day lag = 2.958 (-0.044, 5.960)
                                                                                                                 Cl~ concurrent day =
                                                                                                                  -0.404 (-2.863, 2.055)
                                                                                                                 Cl" 2-day lag = 0.000 (-4.099, 4.099)
                                                                                                                 Cl"3_-day lag =0.202 (-4.716, 5.120)
                                                                                                                 N03 concurrent day =
                                                                                                                 1.796 (-0.939, 4.531)
                                                                                                                 N03" 2-day lag = 2.695 (-0.040, 5.430)
                                                                                                                 N03" 3-day lag = 3.144 (0.409, 5.878)
                                                                                                                 S042 concurrent day =
                                                                                                                 2.120 (-0.032, 4.272)
                                                                                                                 S042" 2-day lag = 2.120 (-0.032, 4.272)
                                                                                                                 S042" 3-day lag =2.120 (-0.032, 4.272)
    December 2009
                                     E-176
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: de Hartog et al. (2003,
    0010611
    
    Period of Study: Winter of 1998-1999
    (in Amsterdam, from Nov 1998-Jun
    1999; in Erfurt, from pet 1998-Apr
    1999; and in Helsinki, from Nov
    1998-Apr 1999.)
    
    Location:
    Amsterdam, the Netherlands
    
    Erfurt, Germany
    
    and Helsinki, Finland
    Outcome: Respiratory symptoms
    
    Age Groups: 2 50 yr
    
    Study Design: Cohort
    
    N: 131 subjects with history of coronary
    heart disease
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Ambient temperature,
    relative humidity, atmospheric pressure,
    incidence of influenza-like illness
    
    Season: Winter
    
    Dose-response Investigated? No
    
    Statistical Package: S-PLUS 2000
    
    Lags Considered: 0-, 1-, 2-, 3-, and
    5-day avg
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD):
    
    Amsterdam, the Netherlands: 20.0
    
    Erfurt, Germany: 23.4
    
    Helsinki, Finland: 12.8
    
    Range (Min, Max):
    
    Amsterdam, the Netherlands: (3.8-82.2)
    
    Erfurt, Germany: (4.5-118.1)
    
    Helsinki, Finland: (3.1-39.8)
    
    Unit (i.e. pg/m3): pg/m3
    
    Monitoring Stations: 1
    
    Co pollutant:
    
    PM10
    
    NCO.01-0.1
    
    CO
    
    N02
    
    SO,
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Association of air pollution and
    incidence of symptoms in three panels
    of elderly subjects
    LagO
    Chest pain w/ physical exertion: 1.04
    (0.96-1.13)
    Shortness of breath: 1.04 (0.96-1.12)
    Awakened,  breathing problems: NA
    Avoidance of activities: 1.04 (0.96-1.14)
    Phlegm: 1.03 (0.93-1.13)
    Lagt
    Chest pain w/ physical exertion: 1.01
    (0.93-1.09)
    Shortness of breath: 1.06 (0.99-1.14)
    Awakened,  breathing problems: 1.09
    (1.00-1.20)
    Avoidance of activities: 1.03 (0.95-1.12)
    Phlegm: 1.10 (1.01-1.19)
    Lag 2
    Chest pain w/ physical exertion: 0.98
    (0.90-1.05)
    Shortness of breath: 1.05 (0.98-1.12)
    Awakened,  breathing problems: 1.04
    (0.95-1.14)
    Avoidance of activities: 1.05 (0.97-1.14)
    Phlegm: 1.08 (1.00-1.18)
    Lag 3
    Chest pain w/ physical exertion: 1.00
    (0.93-1.08)
    Shortness of breath: 1.08 (1.01-1.15)
    Awakened,  breathing problems: 0.99
    (0.91-1.08)
    Avoidance of activities: 1.06 (0.98-1.14)
    Phlegm: 1.10 (1.01-1.19)
    6-day
    Chest pain w/ physical exertion: 1.02
    (0.91-1.13)
    Shortness of breath: 1.12 (1.02-1.24)
    Awakened,  breathing problems: 1.03
    (0.90-1.18)
    Avoidance of activities: OR= 1.09 (0.97-
    1.22)
    Phlegm: OR= 1.16 (1.03-1.32)	
    December 2009
                                     E-177
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Delfino et al. (2004,
    0568971
    
    Period of Study :Sep-Oct 1999
    
    Apr-Jun 2000
    
    Location: Alpine, California
    Outcome: FEVi
    
    Age Groups: 9-19 yr old
    
    Study Design: Panel study
    
    N: 24 children
    
    Statistical Analyses: GLM
    
    Akaike's information criterion and
    Bayesian information criterion
    
    Covariates: Day of wk,  personal
    temperature and relative humidity, time
    of FEVi maneuver (morning, afternoon,
    or evening), Season (fall 1999 or spring
    2000), As-needed medication use,
    Presence or absence of upper or lower
    respiratory infections
    
    Season: Spring, fall
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 0-4
    Pollutant: PM25
    
    Averaging Time: 24-h avg 1-h max
    personal PMIast24h
    
    Mean (SD): 151.0 (12.03) 90th: 292.4
    Range (Min, Max): (9.1,996.8)
    Mean personal PMIast24h
    
    Mean (SD): 37.9 (19.9)
    90th: 65.1
    
    Range (Min, Max): 3.9,113.8
    Home stationary-site PM
    24-h Mean indoor PM25
    
    Mean (SD): 12.1 (5.4)
    90th: 20.2
    
    Range (Min, Max): 2.8, 35.3
    24-h Mean outdoor PM25
    
    Mean (SD): 11.0(5.4)
    90th: 18.4
    
    Range (Min, Max): 1.8, 31.0
    Central outdoor stationary-site PM
    24-h Mean PM25
    
    Mean (SD): 10.3 (5.6)
    90th: 18.4
    
    Range (Min, Max): 1.7, 29.1
    Copollutant (correlation):
    24-h Central HI  PM2 5
    8-h max 03 = 0.24
    8-h Max N02 = 0.73
    8-h Max Personal PM = 0.38
    24-h Mean Personal PM = 0.43
    8-h Max TEOM  PM10 = 0.71
    24-h Mean TEOM PM,0 = 0.78
    24-h Central HI  PM10 = 0.90
    24-h Outdoor HI PM2 5 = 0.89
    24-h Outdoor HI PM,o = 0.72
    24-h Indoor HI PM10 = 0.40
    24-h Indoor HI PM2 5 = 0.73	
    Results presented graphically;
    % predicted FEV, was inversely
    associated with personal exposure to
    fine particles.
    
    Inverse associations of FEV, with
    stationary-site indoor, outdoor and
    central-site gravimetric PM25 and PM10,
    and with hourly TEOM PM,o
    December 2009
                                    E-178
    

    -------
                  Study
    Design & Methods
    Concentrations1
                                                                                                                   Effect Estimates (95% Cl)
    Reference: Delfmo et al. (2006,
    0907451
    
    Period of Study: Region 1: Aug-Mid
    Dec 2003.  Region 2: Jul-Nov 2004
    
    Location:  Region 1: Riverside, CA.
    Region 2: Whittier, CA
                                        Outcome: Fractional Concentration of
                                        Nitric Oxide in exhaled air (FENO)
    
                                        Age Groups: 9 through 18
    
                                        Study Design: Longitudinal Panel
                                        Study
    
                                        N: 45 children
    
                                        Riverside children
    
                                        32 Whittier children
    
                                        Statistical Analyses: Linear mixed-
                                        effects models
    
                                        Two-stage hierarchical model
    
                                        Empirical Variograms
    
                                        Fourth-order polynomial distributed lag
                                        mixed-effects model
    
                                        Covariates: Personal temperature,
                                        Personal Rel. Humid., 10-day exposure
                                        run, Respiratory infections, Region  of
                                        study, Sex, Cumulative daily use of as-
                                        needed B-agonist inhalers
    
                                        Dose-response Investigated? No
    
                                        Lags Considered: 0,1, 2, MA day
                                 Pollutant: PM25
                                 Personal Exposure
                                 Averaging Time: 24 h
                                 Riverside
                                 Mean (SD): 32.78 (21.84)
                                 SOth(Median): 28.14
                                 Range (Min, Max): 7.27, 98.43
                                 Whittier
                                 Mean (SD): 36.2 (25.46) SOth(Median):
                                 29.07
                                 Range (Min, Max): 7.55,197.05
                                 Personal Exposure
                                 Averaging Time: 1 h
                                 Riverside
                                 Mean (SD): 97.94 (70.29)
                                 SOth(Median): 83.7
                                 Range (Min, Max): 14.9, 431.8
    
                                 Whittier
                                 Mean (SD): 93.63 (75.19)
                                 SOth(Median): 71.95
                                 Range (Min, Max): 5.8, 572.9
                                 Personal Exposure
                                 Averaging Time: 8 h
    
                                 Riverside
                                 Mean (SD): 47.21 (30.9) SOth(Median):
                                 38.5
                                 Range (Min, Max): 8.9,132.1
    
                                 Whittier
                                 Mean (SD): 51.75 (36.88)
                                 SOth(Median): 40.15
                                 Range (Min, Max): 8.7, 254.1
    
                                 Central Site
                                 Averaging Time: 24 h
    
                                 Riverside
                                 Mean (SD): 36.63 (23.46)
                                 SOth(Median): 29.26
                                 Range (Min, Max): (9.52, 87.22)
    
                                 Whittier
                                 Mean (SD): 18 (12.14) SOth(Median):
                                 16.3
                                 Range (Min, Max): 2.7, 77.09
                                 Monitoring Stations: 48 personal
                                 nephelometers
                                 2 central sites
                                 Copollutant (correlation):
                                 Personal
                                 24-h personal PM251.00
                                 24-h personal EC 0.18
                                 24-h personal OC 0.15
                                 24-h personal N020.33
                                 24-h central PM25 0.64
                                 24-h central EC 0.12
                                 24-h central OC 0.21
                                 24-h central N02 0.22
                                 Central
                                 24-h personal PM250.64
                                 24-h personal EC 0.00
                                 24-h personal OC-0.11
                                 24-h personal N020.12
                                 24-h central PM251.00
                                 24-h central EC 0.55
                                 24-h central OC 0.66
                                 24-h central N02 0.25	
                                PM Increment: IQR increase
                                (Riverside: 28.41 pg/m3, Whittier 21.87
                                pg/m3)
    
                                Coefficient [Lower Cl, Upper Cl]
                                Mixed-model estimates of the
                                association between personal and
                                central-site air pollutant exposure and
                                FENO
                                LagO
                                Personal 0.42 (-0.15, 0.99)
                                Central 0.03 (-0.68, 0.74)
    
                                Lag1
                                Personal 0.51 (-0.10,1.12)
                                Central 0.44 (-0.28,1.16)
    
                                2-day ma
                                Personal 1.01 (0.14,1.88)
                                Central 0.52 (-0.43,1.47)
                                Stratified by Medication Use
    
                                Lag = 2-day ma
                                Not Taking Anti-lnflamm. Medication
                                Personal 1.11 (-1.39, 3.60)
                                Central 0.44 (-1.65, 2.53)
                                Taking Anti-lnflamm. Medication
                                Personal 1.01 (0.19,1.84)
                                Central 0.55 (-0.47,1.57)
                                Inhaled Corticosteroids
                                Personal 1.58 (0.72, 2.43)
                                Central 1.16 (0.11,2.20)
                                Antileukotrienes +- inhaled
                                corticosteroids
                                Personal -0.89 (-2.73, 0.95)
                                Central-0.75 (-2.83,1.32)
                                Notes:
    
                                Fig of Estimated lag effect of hourly
                                personal PM25 on FENO.
    
                                Fig of the Estimated lag effect of hourly
                                personal PM25 on FENO by use of
                                medications.
    
                                Fig of one- and two-pollutant models for
                                change in FENO using 2-day Ma
                                personal and central-site pollutant
                                measurements.
    December 2009
                             E-179
    

    -------
                  Study
    Design & Methods
    Concentrations1
                                                                                                                    Effect Estimates (95% Cl)
    Reference: Delfmo et al. (2006,
    0907451
    
    Period of Study: Region 1: Aug-Mid
    Dec 2003.  Region 2: Jul-Nov 2004
    
    Location:  Region 1: Riverside, CA.
    Region 2: Whittier, CA
                                        Outcome: Fractional Concentration of
                                        Nitric Oxide in exhaled air (FENO)
    
                                        Age Groups: 9 through 18
    
                                        Study Design: Longitudinal Panel
                                        Study
    
                                        N: 45 children
    
                                        Statistical Analyses: Linear mixed-
                                        effects models
    
                                        Two-stage hierarchical model
    
                                        Empirical Variograms
    
                                        Fourth-order polynomial distributed lag
                                        mixed-effects model
    
                                        Covariates: Personal temperature,
                                        personal rel. humid., 10-day exposure
                                        run, respiratory infections, region of
                                        study, sex, cumulative daily use of as-
                                        needed B-agonist inhalers
    
                                        Dose-response Investigated? No
    
                                        Lags Considered: Lag 0, Lag 1, 2-day
                                        ma
                                 Pollutant: PM25
    
                                 PM Component: EC
    
                                 Personal Exposure
    
                                 Averaging Time: 24 h
    
                                 Riverside
    
                                 Mean (SD): 0.42 (0.69) SOth(Median):
                                 0.34 fjg/m
    
                                 Range (Min, Max): 0.01, 6.94
    
                                 Whittier
    
                                 Mean (SD): 0.78 (1.42)
    
                                 SOth(Median): 0.47
    
                                 Range (Min, Max): 0,17.2
    
                                 Central Site
    
                                 Averaging Time: 24 h
    
                                 Riverside
    
                                 Mean (SD): 1.61 (0.78) SOth(Median):
                                 1.35
    
                                 Range (Min, Max): 0.52, 3.64
    
                                 Whittier
    
                                 Mean (SD): 0.71 (0.43) SOth(Median):
                                 0.63
    
                                 Range (Min, Max): 0.14, 2.95
    
                                 Monitoring Stations: 48 personal
                                 nephelometers,
    
                                 2 central sites
                                 Copollutant (correlation):
                                 Personal
                                 24-h personal PM2 5 0.18
                                 24-h personal EC 1.00
                                 24-h personal OC 0.41
                                 24-h personal N02 0.0.21
                                 24-h central PM25 0.00
                                 24-h central EC 0.04
                                 24-h central OC-0.01
                                 24-h central N02 0.23
                                 Central
                                 24-h personal PM2 5 0.12
                                 24-h personal EC 0.04
                                 24-h personal OC 0.03
                                 24-h personal N02 0.19
                                 24-h central PM25 0.55
                                 24-h central EC 1.00
                                 24-h central OC 0.87
                                 24-h central N02 0.70	
                                PM Increment: IQR increase
                                (Riverside: 28.41 pg/m3, Whittier 21.87
                                pg/m3)
    
                                Coefficient [Lower Cl, Upper Cl] lag:
                                Mixed-model estimates of the
                                association between personal and
                                central-site air pollutant exposure and
                                FENO
    
                                LagO
                                Personal 0.29 (0.10,0.48)
                                Central 0.10 (-0.65, 0.85)
    
                                Lag1
                                Personal-0.01 (-0.23,0.21)
                                Central 0.99 (0.27,1.71)
    
                                2-day ma
                                Personal 0.72 (0.32,1.12)
                                Central 1.38 (0.15, 2.61)
                                Stratified by Medication Use
    
                                Lag = 2-day ma
                                Not Taking Anti-lnflamm. Medication
                                Personal 0.84 (0.08,1.60)
                                Central 1.02 (-2.55, 4.60)
                                Taking Anti-lnflamm. Medication
                                Personal 0.71 (0.28,1.15)
                                Central 1.42 (0.25, 2.60)
                                Inhaled Corticosteroids
                                Personal 0.67 (0.28,1.07)
                                Central 1.28 (0.07, 2.49)
                                Antileukotrienes +- inhaled
                                corticosteroids
                                Personal 0.03 (-3.29, 3.35)
                                Central 1.15 (-1.58, 3.88)
                                Notes:
    
                                Fig of Estimated lag effect of hourly
                                personal PM25 on FENO.
    
                                Fig of the estimated lag effect of hourly
                                personal PM25 on FENO by use of
                                medications.
    
                                Fig of one- and two-pollutant models for
                                change in FENO using 2-day Ma
                                personal and central-site pollutant
                                measurements.
    December 2009
                             E-180
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Delfino et al. (2006,
    0907451
    
    Period of Study: Region 1: Aug-Mid
    Dec 2003.  Region 2: Jul through Nov
    2004
    
    Location:  Region 1: Riverside, CA.
    Region 2: Whittier, CA
    Outcome: Fractional Concentration of
    Nitric Oxide in exhaled air (FENO)
    
    Age Groups: 9 through 18
    
    Study Design: Longitudinal Panel
    Study
    
    N: 45 children
    
    Statistical Analyses: Linear mixed-
    effects models
    
    Two-stage hierarchical model
    
    Empirical Variograms
    
    Fourth-order polynomial distributed lag
    mixed-effects model
    
    Covariates: Personal temperature,
    personal rel. humid., 10-day exposure
    run, respiratory infections, region of
    study, sex, cumulative daily use of as-
    needed B-agonist inhalers
    
    Dose-response Investigated? No
    
    Lags Considered: Lag 0, Lag 1, 2-day
    ma
    Pollutant: PM25
    
    PM Component: OC
    
    Personal Exposure
    
    Averaging Time: 24 h
    
    Riverside
    
    Mean (SD): 5.63 (2.59) SOth(Median):
    4.98
    
    Range (Min, Max): 1.94,12.38
    
    Whittier
    
    Mean (SD): 6.81 (3.45) SOth(Median):
    6.43
    
    Range (Min, Max): 2.18, 31.5
    
    Central Site
    
    Averaging Time: 24 h
    
    Riverside
    
    Mean (SD): 6.88 (1.86)
    
    Percentiles: 50th
    
    Median: 6.07
    
    Range (Min, Max): 4.11,11.62
    
    Whittier
    
    Mean (SD): 3.93 (1.49) SOth(Median):
    3.76
    
    Range (Min, Max): 1.64, 8.82
    
    Monitoring Stations: 48 personal
    nephelometers,
    
    2 central sites
    Copollutant (correlation):
    Personal
    24-h personal PM250.15
    24-h personal EC 0.41
    24-h personal OC 1.00
    24-h personal N020.20
    24-h central PM2 5-0.11
    24-h central EC 0.03
    24-h central OC-0.02
    24-h central N02 0.21
    Central
    24-h personal PM250.21
    24-h personal EC-0.01
    24-h personal OC-0.02
    24-h personal N020.17
    24-h central PM25 0.66
    24-h central EC 0.87
    24-h central OC 1.00
    24-h central N02 0.62	
    PM Increment: IQR increase
    (Riverside: 28.41 pg/m3, Whittier 21.87
    pg/m3)
    
    Mixed-model estimates of the
    association between personal and
    central-site air pollutant exposure and
    FENO
    LagO
    Personal 0.51 (-0.28,1.30)
    Central 0.93 (-0.20, 2.06)
    
    Lag1
    Personal 0.13 (-0.77,1.03)
    CentralO.51 (-0.64,1.66)
    
    2-day ma
    Personal 0.94 (-0.47, 2.35)
    Central 1.6 (-0.17,  3.37)
    Stratified by Medication Use
    
    Lag = 2-day ma.
    Not Taking Anti-lnflamm. Medication
    Personal 0.88 (-1.62, 3.38)
    Central 0.36 (-4.07, 4.79)
    Taking Anti-lnflamm. Medication
    Personal 0.87 (-0.79, 2.53)
    Central 2.05 (0.24, 3.86)
    Inhaled Corticosteroids
    Personal 2.47 (0.30, 4.64)
    Central 1.96 (0.14, 3.78)
    Antileukotrienes +- inhaled
    corticosteroids
    Personal 0.52 (-1.99, 3.02)
    Central 1.29 (-2.58, 5.15)
    Notes:
    
    Fig of Estimated lag effect of hourly
    personal PM25 on FENO.
    
    Fig of the Estimated lag effect of hourly
    personal PM25 on FENO by use of
    medications.
    
    Fig of one- and two-pollutant models  for
    change in FENO using 2-day Ma
    personal and central-site pollutant
    measurements
    December 2009
                                     E-181
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Dubowsky et al. (2006,
    0887501
    
    Period of Study: Mar 2002-Jun
    2002
    
    Location: St. Louis, Missouri
    Outcome: Chronic inflammation,
    Diabetes, Obesity, Hypertension,
    Cardiac Risk
    
    Study Design:
    
    Prospective Cohort
    
    Statistical Analyses:
    
    Poisson, LOESS
    
    Age Groups:
    
    >60
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Mean (SD) unit: 16 (6.0)
    
    Range (Min, Max): 6.5, 28
    
    Co pollutants:
    
    BC
    
    CO
    
    N02
    
    S02
    
    03
    Increment: 5.4 pg/m
    
    % Increase (Lower Cl, Upper Cl)
    
    Lag
    
    % increase in inflammatory response
    and exposure to PM25 in people > 60
    Inflammatory Marker:
    IL-6:-8(-16, 8)
    1:-6(-10, 5
    2:-5 (-11, 6)
    3: -3 (-9, 6)
    4:-4 (-12, 10)
    5:-5 (-13, 8)
    6:-6 (-14, 9)
    7
    CRP:-2(-22, 15)
    1:3 (-8, 17)
    2: 4 (-9, 20)
    3: 9 (-4, 27)
    4:11 (-5, 35)
    5: 8 (-9, 29)
    6: 5 (-12, 26)
    7
    WBC: 0 (-2, 4)
    1:1 (-1,2)
    2: 2 (-1,3)
    3:1 (-2, 5)
    4: 3 (-1,10)
    5:5(0,12)
    6:8(0, 14)
    
    % Increase in inflammatory responses
    and exposure to ambient PM25
    concentrations in people > 60
    Inflammatory Marker:
    CRP
    All conditions*: 14 (-5.4, 37)
    0-5 avg
    3 conditions met*: 81 (21,172)
    0-5 avg
    2 conditions met*: 11 (-7.3,33)
    0-5 avg
    IL-6
    All conditions*:-2.1 (-13,11)
    0-5 avg
    3 conditions met*: 23 (-5.3, 59)
    0-5 avg
    2 conditions met*:-3.1 (-14,9.7)
    0-5 avg
    WBC
    All conditions*: 3.4 (-1.8, 8.9)
    0-5 avg
    3 conditions met*: 0.4 (-8.8,11)
    0-5 avg
    2 conditions met*: 3.6 (-1.7, 9.1)
    0-5 avg
    *AII conditions met means model is
    adjusted for sex, obesity, diabetes,
    smoking history, ambient and
    microenvironmental  apparent
    temperature, mold, pollen, trip, h, and
    vitamins.
    
    Three conditions met means model is
    adjusted for three of the variables.
    
    Two conditions met means model is
    adjusted for 2 of the variables.
    December 2009
                                    E-182
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Ebelt et al. (2005, 0569071
    
    Period of Study: Summer of 1998
    
    Location: Vancouver, Canada
    Outcome: spirometry,
    
    Age Groups: range from 54-86 yr
    
    Mean age= 74 yr
    
    Study Design: extended analysis of a
    repeated-measures panel study
    
    N: 16 persons with COPD
    
    Statistical Analyses: Earlier analysis
    expanded by developing mixed-effect
    regression models and by evaluating
    additional exposure indicators
    
    Dose-response Investigated? No
    
    Statistical Package: SAS V8
    Pollutant: PM25
    
    Averaging Time: 24 h
    Mean (SD):
    Ambient PM25:11.4 (4.6)
    Exposure to ambient PM25: 7.9 (3.7)
    Nonsulfate ambient PM25: 9.3 (3.7)
    Exposure to nonsulfate ambient PM25:
    6.5 (3.0)
    Total exposure to PM25:18.5 (14.9)
    Exposure to nonambient PM25:10.6
    (14.5)
    Range (Min, Max):
    Ambient PM25: (4.2-28.7)
    Exposure to ambient PM25: (0.9-21.3)
    Nonsulfate ambient PM25: (3.3-23.3)
    Exposure to nonsulfate ambient PM25:
    (0.7-16.9)
    Total exposure to PM25: (2.2-90.9)
    Exposure to nonambient PM25: (-2.6-
    85.0)
    Monitoring Stations: 5
    Copollutant (correlation):
    Ambient PM,0: r= 0.78
    Ambient PM10.25: r=0.15
    Ambient Sulfate-0.82
    Nonsufate Ambient PM25: r= 0.98
    PM Increment: Ambient PM25: 5.8
    (IQR)
    
    Exposure to ambient PM25: 4.4 (IQR)
    
    Nonsulfate ambient PM25: 4.2 (IQR)
    
    Exposure to nonsulfate ambient PM25:
    3.4 (IQR)
    
    Total exposure to PM25:10.1 (IQR)
    
    Exposure to nonambient PM25: 8.9
    (IQR)
    
    Notes: Effect estimates are presented
    in Fig 2 and Electronic Appendix Table
    1 (only available with electronic version
    of article) and not provided
    quantitatively elsewhere.
    Reference: Ebelt et al. (2005, 0569071
    
    Period of Study: Summer of 1998
    
    Location: Vancouver, Canada
    Outcome: spirometry
    
    Age Groups: Range from 54-86 yr
    
    Mean age= 74 yr
    
    Study Design: extended analysis of a
    repeated-measures panel study
    
    N: 16 persons with COPD
    
    Statistical Analyses: Earlier analysis
    expanded by developing mixed-effect
    regression models and by evaluating
    additional exposure indicators
    
    Dose-response Investigated? No
    
    Statistical Package: SAS V8
    Pollutant: Sulfate (S04)
    
    Averaging Time: 24 h
    Mean (SD):
    Ambient Sulfate: 2.0 (1.1)
    Exposure to Ambient Sulfate: 0.2 (4.7)
    
    Range (Min, Max):
    Ambient Sulfate: (0.4-5.4)
    Exposure to ambient Sulfate: (0.2-4.7)
    
    Monitoring Stations: 5
    
    Copollutant (correlation):
    Ambient PM25:r= 0.82
    Nonsulfate Ambient PM25: r= 0.74
    Exposure to Ambient Sulfate: r= 0.82
    PM Increment: Ambient Sulfate: 1.5
    (IQR)
    
    Exposure to Ambient Sulfate: 0.9 (IQR)
    
    Notes: Effect estimates are presented
    in Fig 2 and Electronic Appendix Table
    1 (only available with electronic version
    of article) and not provided
    quantitatively elsewhere.
    Reference: Ferdinands et al. (2008,
    1564331
    Period of Study: Aug 2004
    
    Location: Atlanta, Georgia
    Outcome: Respiratory Symptoms,
    airway inflammation
    
    Study Design: Prospective cohort
    
    Statistical Analyses: Pearson
    Correlation Analysis
    
    Age Groups: 14-18
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Mean (SD) unit: 27.2 (11.9)
    
    Range (Min, Max): 21.7, 34.7
    
    Copollutants (correlation):
    03: r= 0.8-0.9
    The study presents results qualitatively
    not quantitatively.
    Reference: Gent et al. (2003, 0528851
    Period of Study: Apr-Sep 2001
    Location: Connecticut
    Springfield, MA
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Respiratory symptoms
    including: Wheeze, persistent cough,
    chest tightness, shortness of breath
    Age Groups: Infants
    Study Design: 1-yr prospective cohort
    study
    N: 1002 infants
    
    171 60 observations
    Statistical Analyses: Logistic
    regression analysis
    GEEs
    
    Tests for linear trend
    
    Test for goodness of fit
    Hosmer-Lemeshow statistic for
    regression
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 13. 1(7.9)
    Percentiles: 20th: 6.9
    40th: 9.0
    SOth(Median): 10.3
    60th: 12.1
    80th: 19.0
    Range (Min, Max): 3.7, 44.2
    Monitoring Stations: 4 sites
    Copollutant (correlation):
    Temperature: 0.58
    
    
    
    
    
    PM Increment: 12 pg/m3 same day
    19 pg/m3 previous day
    Model 6 (same day)
    Wheeze <6. 9 =1.00
    6.9-8.9 = 0.95(0.83,1.10)
    9.0-12.0=1.04(0.89, 1.20)
    12.1-18.9=1.05(0.92, 1.20)
    > 19.0 = 0.93 (0.78, 1.11)
    Persistent Cough <6.9=1.00
    6.9-8.9 = 0.95(0.87, 1.04)
    9.0-12.0 = 0.96(0.87,1.06)
    12.1-18.9=1.00(0.91, 1.09)
    > 19.0 = 0.95 (0.83, 1.09)
    Chest Tightness <6. 9 =1.00
    6.9-8.9=1.01 (0.86, 1.19)
    9.0-12.0=1.06(0.89, 1.26)
    12.1-18.9=1.24(1.06,1.45)
    > 19.0 =1.05 (0.84, 1.33)
    Shortness of Breath <6.9 = 1 .00
    6.9-8.9=1.01(0.87,1.17)
    9.0-12.0=1.03(0.87, 1.22)
    December 2009
                                    E-183
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                       Covariates: Temperature
    
                                       Dose-response Investigated? No
    
                                       Statistical Package: SAS
    
                                       Lags Considered: 1-day lag
                                                                   12.1-18.9=1.07(0.91, 1.25)
                                                                   > 19.0 =1.03 (0.83, 1.28)
                                                                   Bronchodilator<6.9 = 1.00
                                                                   6.9-8.9=1.04(0.99, 1.09)
                                                                   9.0-12.0=1.02(0.96, 1.08)
                                                                   12.1-18.9=1.04(0.99,1.09)
                                                                   > 19.0 =1.02 (0.97, 1.08)
                                                                   Model 6 (previous day)
                                                                   Wheeze <6.9 =1.00
                                                                   6.9-8.9=1.06(0.95, 1.20)
                                                                   9.0-12.0=1.09(0.94, 1.28)
                                                                   12.1-18.9=1.03(0.89,1.19)
                                                                   > 19.0 =1.14 (0.97, 1.34)
                                                                   Persistent Cough <6.9=1.00
                                                                   6.9-8.9=1.04(0.94,1.14)
                                                                   9.0-12.0=1.05(0.94, 1.17)
                                                                   12.1-18.9=1.03(0.94, 1.14)
                                                                   > 19.0= 1.12 (1.02 1.24)
                                                                   Chest Tightness <6.9 =1.00
                                                                   6.9-8.9=1.03(0.87, 1.23)
                                                                   9.0-12.0=1.04(0.85,1.27)
                                                                   12.1-18.9=1.00(0.84, 1.19)
                                                                   > 19.0 =1.21 (1.00, 1.46)
                                                                   Shortness of Breath <6.9 = 1.00
                                                                   6.9-8.9=1.00(0.84, 1.19)
                                                                   9.0-12.0=1.09(0.90, 1.31)
                                                                   12.1-18.9=1.09(0.90,1.31)
                                                                   > 19.0 =1.26 (1.02, 1.54)
                                                                   Bronchodilator <6.9 = 1.00
                                                                   6.9-8.9 = 0.98(0.94,1.03)
                                                                   9.0-12.0 = 0.99(0.95, 1.03)
                                                                   12.1-18.9 = 0.97(0.94, 1.01)
                                                                   > 19.0 = 0.99 (0.95, 1.04)
                                                                   PM2.5 + 03:
                                                                   Medication Users: Same-day
                                                                   Wheeze <6.9 =1.00
                                                                   6.9-8.9 = 0.89(0.75, 1.29)
                                                                   9.0-12.0=1.02(0.87, 1.19)
                                                                   12.1-18.9 = 0.94(0.77,1.15)
                                                                   > 19.0 = 0.83 (0.65, 1.06)
                                                                   Persistent Cough <6.9 = 1.00
                                                                   6.9-8.9 = 0.95(0.84,1.06)
                                                                   9.0-12.0 = 0.97(0.86, 1.10)
                                                                   12.1-18.9 = 0.94(0.77, 1.15)
                                                                   > 19.0 = 0.83 (0.65, 1.06)
                                                                   Chest Tightness <6.9 =1.00
                                                                   6.9-8.9 = 0.90(0.74, 1.09)
                                                                   9.0-12.0 = 0.97(0.79,1.18)
                                                                   12.1-18.9 = 0.97(0.76,1.25)
                                                                   > 19.0 = 0.76 (0.54, 1.05)
                                                                   Shortness of Breath <6.9 = 1.00
                                                                   6.9-8.9 = 0.95(0.80, 1.12)
                                                                   9.0-12.0=1.00(0.82, 1.21)
                                                                   12.1-18.9 = 0.90(0.73,1.12)
                                                                   > 19.0 = 0.87 (0.65, 1.17)
                                                                   Bronchodilator <6.9 = 1.00
                                                                   6.9-8.9=1.03(0.98,1.08)
                                                                   9.0-12.0=1.01  (0.96, 1.07)
                                                                   12.1-18.9=1.02(0.95, 1.08)
                                                                   > 19.0 = 0.99 (0.91, 1.07)
                                                                   Previous Day
                                                                   Wheeze <6.9 =1.00
                                                                   6.9-8.9=1.03(0.89,1.18)
                                                                   9.0-12.0=1.05(0.88, 1.24)
                                                                   12.1-18.9 = 0.98(0.82, 1.17)
                                                                   > 19.0 =1.05 (0.85, 1.29)
                                                                   Persistent Cough <6.9 = 1.00
                                                                   6.9-8.9 = 0.99(0.89, 1.11)
                                                                   9.0-12.0 = 0.98(0.86,1.10)
                                                                   12.1-18.9 = 0.95(0.83,1.10)
                                                                   > 19.0 =1.00 (0.88, 1.15)
                                                                   Chest Tightness <6.9 =1.00
                                                                   6.9-8.9 = 0.89(0.72, 1.10)
                                                                   9.0-12.0 = 0.90(0.70, 1.16)
                                                                   12.1-18.9 = 0.81(0.63,1.03)
                                                                   > 19.0 = 0.91 (0.71, 1.17)
                                                                   Shortness of Breath <6.9 = 1.00
                                                                   6.9-8.9 = 0.96(0.78,1.18)
    December 2009
                            E-184
    

    -------
                  Study
                                              Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                                                             9.0-12.0=1.00(0.81, 1.25)
                                                                                                             12.1-18.9 = 0.96(074, 1.24)
                                                                                                             > 19.0 =1.20 (0.94, 1.52)
                                                                                                             Bronchodilator <6.9 = 1.00
                                                                                                             6.9-8.9 = 0.99(0.94, 1.04)
                                                                                                             9.0-12.0 = 0.97(0.93,1.02)
                                                                                                             12.1-18.9 = 0.96(0.91,1.02)
                                                                                                             > 19.0 = 0.97 (0.89, 1.04)
                                                                                                             PM25 + 03:
                                                                                                             Non-users: Same-day
                                                                                                             Wheeze <6.9 =1.00
                                                                                                             6.9-8.9 = 0.92(0.72,1.17)
                                                                                                             9.0-12.0=1.08(0.85, 1.36)
                                                                                                             12.1-18.9 = 0.94(0.73, 1.22)
                                                                                                             > 19.0 =1.15 (0.75, 1.75)
                                                                                                             Persistent Cough <6.9 = 1.00
                                                                                                             6.9-8.9 = 0.96(0.83, 1.12)
                                                                                                             9.0-12.0=1.02(0.89,1.18)
                                                                                                             12.1-18.9 = 0.93(0.78,1.12)
                                                                                                             > 19.0 =1.07 (0.85, 1.34)
                                                                                                             Chest Tightness <6.9 =1.00
                                                                                                             6.9-8.9 = 0.84(0.54, 1.31)
                                                                                                             9.0-12.0=1.09(0.74, 1.61)
                                                                                                             12.1-18.9 = 0.78(0.47,1.30)
                                                                                                             > 19.0 = 0.71  (0.36, 1.39)
                                                                                                             Shortness of Breath <6.9 = 1.00
                                                                                                             6.9-8.9 = 0.61(0.39,0.95)
                                                                                                             9.0-12.0=1.13(0.85, 1.50)
                                                                                                             12.1-18.9 = 0.72(0.42, 1.23)
                                                                                                             > 19.0 =1.17 (0.72, 1.90)
                                                                                                             Bronchodilator Use: <6.9 = 1.00
                                                                                                             6.9-8.9 = 0.95(0.78, 1.15)
                                                                                                             9.0-12.0 = 0.95(0.78,1.16)
                                                                                                             12.1-18.9 = 0.85(0.69,1.06)
                                                                                                             > 19.0 = 0.99 (0.76, 1.30)
                                                                                                             Previous-day
                                                                                                             Wheeze <6.9= 1.00
                                                                                                             6.9-8.9=1.01 (0.78, 1.31)
                                                                                                             9.0-12.0=1.15(0.88,1.51)
                                                                                                             12.1-18.9=1.08(0.78,1.51)
                                                                                                             a 19.0=1.18(0.71,1.97)
                                                                                                             Persistent Cough <6.9= 1.00
                                                                                                             6.9-8.9=1.07(0.94, 1.22)
                                                                                                             9.0-12.0=1.13(0.97, 1.32)
                                                                                                             12.1-18.9=1.03(0.87,1.22)
                                                                                                             > 19.0 =1.14 (0.88, 1.46)
                                                                                                             Chest Tightness <6.9 =1.00
                                                                                                             6.9-8.9=1.44(0.90,2.30)
                                                                                                             9.0-12.0=1.50(0.97,2.33)
                                                                                                             12.1-18.9=1.56(0.91,2.66)
                                                                                                             > 19.0 =1.76 (0.83, 3.73)
                                                                                                             Shortness of Breath <6.9 = 1.00
                                                                                                             6.9-8.9 = 0.99(0.75, 1.30)
                                                                                                             9.0-12.0=1.30(0.88,1.91)
                                                                                                             12.1-18.9 = 0.84(0.57,1.24)
                                                                                                             > 19.0 =1.48 (0.94, 2.34)
                                                                                                             Bronchodilator Use <6.9 = 1.00
                                                                                                             6.9-8.9=1.05(0.85, 1.34)
                                                                                                             9.0-12.0=1.28(1.01, 1.62)
                                                                                                             12.1-18.9=1.05(0.80,1.37)
                                                                                                             a 19.0=1.19(0.83,1.71)
                                                                                                             Notes: Line graphs of daily levels of 03
                                                                                                             and PM25 and daily temperature with
                                                                                                             daily prevalence of respiratory
                                                                                                             symptoms for users of asthma
                                                                                                             maintenance medication
    Reference: Gent et al, (2009,1803991   Outcome: Increased asthma symptoms  Pollutant: PM25 and components
                                       and medication use
                                                                          Averaging Time: Daily
                                       Study Design: Panel
    Period of Study: 2000-2003
    
    Location: New Haven County CT
                                       Covariates: Season, day of the week,
                                       date
    
                                       Statistical Analysis: Logistic
                                       regression
    
                                       Statistical Package: SAS
    Mean: (estimated sources, pg/m ]
    
    Motor Vehicle: 6.6
    
    Road Dust: 2.3
    
    Sulfur: 5.5
    Odds Ratio and p-value for
    sources and components of PIVh.s.
    
    Lags are 0,1 or 2 days, and the mean
    of days 0-2 (L02).
    
    Source: Motor Vehicle
    EC, Increment = 1000ng/m3
    Wheeze
    L0:1.04, p = 0.04
    L1:1.01, p = 0.70	
    December 2009
                                                                      E-185
    

    -------
                  Study
           Design & Methods
            Concentrations1
    Effect Estimates (95% Cl)
                                                                                                               L2:1.00, p = 0.99
                                                                                                               L02:1.07, p = 0.06
                                                                                                               Persistent Cough
                                                                                                               L0:1.01,p = 0.42
                                                                                                               L1:1.01, p = 0.38
                                                                                                               L2:0.99, p = 0.44
                                                                                                               L02:1.03, p = 0.23
                                                                                                               Shortness of Breath
                                                                                                               LO: 1.06, p = 0.001
                                                                                                               L1:1.01,p = 0.65
                                                                                                               L2:1.01,p = 0.63
                                                                                                               L02:1.12, p = 0.01
                                                                                                               Chest Tightness
                                                                                                               L0:1.03, p = 0.20
                                                                                                               L1:1.02, p = 0.24
                                                                                                               L2:1.01,p = 0.59
                                                                                                               L02:1.10, p = 0.04
                                                                                                               Inhaler Use
                                                                                                               LO: 1.01, p = 0.15
                                                                                                               L1:1.00, p = 0.72
                                                                                                               L2:1.00, p = 0.75
                                                                                                               L02:1.02, p = 0.40
    
                                                                                                               Zn, Increment = 10ng/m3
                                                                                                               Wheeze
                                                                                                               L0:1.00, p = 0.69
                                                                                                               L1: 0.99, p = 0.54
                                                                                                               L2:1.00, p = 0.89
                                                                                                               L02:1.00, p = 0.98
                                                                                                               Persistent Cough
                                                                                                               L0:1.00, p = 0.60
                                                                                                               L1:1.00, p = 0.77
                                                                                                               L2: 0.99, p = 0.24
                                                                                                               L02:1.00, p = 0.94
                                                                                                               Shortness of Breath
                                                                                                               LO: 1.02, p = 0.001
                                                                                                               L1:1.00, p = 0.57
                                                                                                               L2:1.01,p = 0.49
                                                                                                               L02:1.04, p = 0.06
                                                                                                               Chest Tightness
                                                                                                               L0:1.00, p = 0.72
                                                                                                               L1:1.00, p = 0.96
                                                                                                               L2:1.01,p = 0.38
                                                                                                               L02:1.03, p = 0.13
                                                                                                               Inhaler Use
                                                                                                               L0:1.00, p = 0.41
                                                                                                               L1:1.00, p = 0.44
                                                                                                               L2:1.00, p = 0.52
                                                                                                               L02:1.01,p = 0.53
    
                                                                                                               Pb, Increment = 5 ng/m3
                                                                                                               Wheeze
                                                                                                               L0:1.02, p = 0.31
                                                                                                               L1:1.00, p = 0.91
                                                                                                               L2:1.01,p = 0.62
                                                                                                               L02:1.07, p = 0.13
                                                                                                               Persistent Cough
                                                                                                               L0:1.02, p = 0.25
                                                                                                               L1:1.00, p = 0.88
                                                                                                               L2:1.00, p = 0.87
                                                                                                               L02:1.05, p = 0.12
                                                                                                               Shortness of Breath
                                                                                                               L0:1.03, p = 0.11
                                                                                                               L1: 0.98, p = 0.51
                                                                                                               L2:1.03, p = 0.05
                                                                                                               L02:1.12, p = 0.01
                                                                                                               Chest Tightness
                                                                                                               L0:1.02, p = 0.31
                                                                                                               L1: 0.99, p = 0.79
                                                                                                               L2:1.03, p = 0.13
                                                                                                               L02:1.10, p = 0.02
                                                                                                               Inhaler Use
                                                                                                               L0:1.01,p = 0.06
                                                                                                               L1: 0.98, p = 0.11
                                                                                                               L2:1.02, p = 0.04
                                                                                                               L02:1.04, p = 0.10
                                                                                                               Cu, Increment = 5  ng/m
                                                                                                               Wheeze
    Age Groups: Children aged 4-12
    Biomass Burning: 0.9
    
    Oil: 0.8
    
    Sea Salt: 0.5
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    December 2009
                                    E-186
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                               LO: 1.01, p = 0.59
                                                                                                               L1:0.99, p = 0.55
                                                                                                               L2:0.99, p = 0.82
                                                                                                               L02:1.02, p = 0.67
                                                                                                               Persistent Cough
                                                                                                               L0:1.02, p = 0.13
                                                                                                               L1:1.02, p = 0.21
                                                                                                               L2:0.98, p = 0.26
                                                                                                               L02:1.05, p = 0.04
                                                                                                               Shortness of Breath
                                                                                                               L0:1.06, p = 0.01
                                                                                                               L1:1.01,p = 0.74
                                                                                                               L2:0.96, p = 0.10
                                                                                                               L02:1.06, p = 0.21
                                                                                                               Chest Tightness
                                                                                                               L0:10.3, p = 0.23
                                                                                                               L1:1.02, p = 0.42
                                                                                                               L2:0.97, p = 0.17
                                                                                                               L02:1.04, p = 0.39
                                                                                                               Inhaler Use
                                                                                                               L0:1.01,p = 0.22
                                                                                                               L1:0.99, p = 0.37
                                                                                                               L2:1.00, p = 0.70
                                                                                                               L02:1.01,p = 0.46
    
                                                                                                               Se, Increment = 1 ng/m3
                                                                                                               Wheeze
                                                                                                               L0:1.00, p = 0.97
                                                                                                               L1:0.99, p = 0.52
                                                                                                               L2:1.00, p = 0.91
                                                                                                               L02:1.02, p = 0.71
                                                                                                               Persistent Cough
                                                                                                               L0:1.00, p = 0.84
                                                                                                               L1:0.99, p = 0.32
                                                                                                               L2:1.00, p = 0.93
                                                                                                               L02:0.98, p = 0.43
                                                                                                               Shortness of Breath
                                                                                                               L0:1.02, p = 0.40
                                                                                                               L1:0.97, p = 0.10
                                                                                                               L2:1.01,p = 0.55
                                                                                                               L02:1.02, p = 0.67
                                                                                                               Chest Tightness
                                                                                                               L0:1.00, p = 0.79
                                                                                                               L1:0.97, p = 0.13
                                                                                                               L2:1.01,p = 0.72
                                                                                                               L02:0.98, p = 0.61
                                                                                                               Inhaler Use
                                                                                                               L0:0.99, p = 0.20
                                                                                                               L1:1.01, p = 0.02
                                                                                                               L2:0.99, p = 0.32
                                                                                                               L02:0.99, p = 0.75
                                                                                                               Source: Road Dust
    
                                                                                                               Si, Increment =100 ng/m3
                                                                                                               Wheeze
                                                                                                               L0:1.03, p = 0.03
                                                                                                               L1:1.00, p = 0.99
                                                                                                               L2:1.02, p = 0.26
                                                                                                               L02:1.07, p = 0.04
                                                                                                               Persistent Cough
                                                                                                               L0:1.02, p = 0.01
                                                                                                               L1:1.00, p = 0.78
                                                                                                               L2:1.01,p = 0.60
                                                                                                               L02:1.05, p = 0.02
                                                                                                               Shortness of Breatl04, p = 0.01h
                                                                                                               L0:1.04, p = 0.01
                                                                                                               L1:1.01,p = 0.60
                                                                                                               L2:1.01,p = 0.63
                                                                                                               L02:1.08, p = 0.02
                                                                                                               Chest Tightness
                                                                                                               L0:1.02, p = 0.20
                                                                                                               L1:1.02, p = 0.17
                                                                                                               L2:1.00, p = 0.88
                                                                                                               L02:1.06, p = 0.10
                                                                                                               Inhaler Use
                                                                                                               LO: 1.02, p = 0.004
                                                                                                               L1:0.99, p = 0.18
                 	L2:1.01,p = 0.45	
    December 2009                                                    E-187
    

    -------
                  Study                       Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
                                                                                                                L02:1.03, p = 0.09
                                                                                                                Fe, Increment = 100 ng/m3
                                                                                                                Wheeze
                                                                                                                L0:1.04, p = 0.02
                                                                                                                L1:1.00, p = 0.80
                                                                                                                L2:1.00, p = 0.87
                                                                                                                L02:1.07, p = 0.05
                                                                                                                Persistent Cough
                                                                                                                L0:1.02, p = 0.06
                                                                                                                L1:1.01, p = 0.52
                                                                                                                L2:0.99, p = 0.52
                                                                                                                L02:1.04, p = 0.04
                                                                                                                Shortness of Breath
                                                                                                                LO: 1.06, p = 0.002
                                                                                                                L1:1.01,p = 0.65
                                                                                                                L2:0.98, p = 0.27
                                                                                                                L02:1.08, p = 0.04
                                                                                                                Chest Tightness
                                                                                                                L0:1.01,p = 0.47
                                                                                                                L1:1.02, p = 0.22
                                                                                                                L2:0.98, p = 0.35
                                                                                                                L02:1.05, p = 0.21
                                                                                                                Inhaler Use
                                                                                                                LO: 1.02, p = 0.004
                                                                                                                L1:0.99, p = 0.44
                                                                                                                L2:1.00, p = 0.91
                                                                                                                L02:1.03, p = 0.08
    
                                                                                                                Al, Increment = 50 ng/m3
                                                                                                                Wheeze
                                                                                                                L0:1.02, p = 0.17
                                                                                                                L1:1.01,p = 0.73
                                                                                                                L2:1.02, p = 0.30
                                                                                                                L02:1.07, p = 0.03
                                                                                                                Persistent Cough
                                                                                                                LO: 1.03, p = 0.001
                                                                                                                L1:1.00, p = 0.96
                                                                                                                L2:1.00, p = 0.68
                                                                                                                L02:1.06, p = 0.01
                                                                                                                Shortness of Breath
                                                                                                                LO: 1.05, p = 0.002
                                                                                                                L1:1.01,p = 0.63
                                                                                                                L2:1.01,p = 0.59
                                                                                                                L02:1.09, p = 0.004
                                                                                                                Chest Tightness
                                                                                                                L0:1.02, p = 0.21
                                                                                                                L1:1.02, p = 0.18
                                                                                                                L2:1.00, p = 0.94
                                                                                                                L02:1.07, p = 0.04
                                                                                                                Inhaler Use
                                                                                                                L0:1.02, p = 0.02
                                                                                                                L1: 0.99, p = 0.27
                                                                                                                L2:1.01,p = 0.50
                                                                                                                L02:1.02, p = 0.11
                                                                                                                Ca, Increment = 50 ng/m
                                                                                                                Wheeze
                                                                                                                L0:1.07, p = 0.02
                                                                                                                L1:1.00, p = 0.97
                                                                                                                L2:1.01,p = 0.74
                                                                                                                L02:1.14, p = 0.04
                                                                                                                Persistent Cough
                                                                                                                L0:1.05, p = 0.01
                                                                                                                L1: 0.99, p = 0.64
                                                                                                                L2:1.00, p = 0.90
                                                                                                                L02:1.09, p = 0.03
                                                                                                                Shortness of Breath
                                                                                                                LO: 1.10, p = 0.002
                                                                                                                L1:1.02, p = 0.66
                                                                                                                L2:1.00, p = 0.89
                                                                                                                L02:1.18, p = 0.01
                                                                                                                Chest Tightness
                                                                                                                L0:1.04, p = 0.26
                                                                                                                L1:1.03, p = 0.43
                                                                                                                L2:1.00, p = 0.93
                                                                                                                L02:1.14, p = 0.07
                                                                                                                Inhaler Use
                                                                                                                L0:1.04, p = 0.01	
    December 2009                                                    E-188
    

    -------
                  Study                       Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                              L1:0.97, p = 0.06
                                                                                                              L2:1.01,p = 0.44
                                                                                                              L02:1.04, p = 0.17
                                                                                                              Ba, Increment = 10ng/m3
                                                                                                              Wheeze
                                                                                                              L0:0.99,  p = 0.57
                                                                                                              L1:1.00,  p = 0.92
                                                                                                              L2:0.99,  p = 0.48
                                                                                                              L02:0.99, p = 0.81
                                                                                                              Persistent Cough
                                                                                                              L0:1.00,  p = 0.83
                                                                                                              L1:1.01,  p = 0.38
                                                                                                              L2:0.99,  p = 0.32
                                                                                                              L02:1.00, p = 0.81
                                                                                                              Shortness of Breath
                                                                                                              L0:1.04,  p = 0.02
                                                                                                              L1:1.00,  p = 0.96
                                                                                                              L2:0.96,  p = 0.05
                                                                                                              L02:1.03, p = 0.38
                                                                                                              Chest Tightness
                                                                                                              L0:1.01,p = 0.63
                                                                                                              L1:1.00,  p = 0.88
                                                                                                              L2:0.98,  p = 0.30
                                                                                                              L02:1.02, p = 0.51
                                                                                                              Inhaler Use
                                                                                                              L0:1.01,p = 0.08
                                                                                                              L1:0.99,  p = 0.19
                                                                                                              L2:1.00,  p = 0.92
                                                                                                              L02:1.01,p = 0.36
    
                                                                                                              Ti, lncrement = 5ng/m3
                                                                                                              Wheeze
                                                                                                              L0:1.00,  p = 0.59
                                                                                                              L1:0.99,  p = 0.49
                                                                                                              L2:1.01,p = 0.34
                                                                                                              L02:1.01,p = 0.56
                                                                                                              Persistent Cough
                                                                                                              L0:1.00,  p = 0.57
                                                                                                              L1:1.00,  p = 0.55
                                                                                                              L2:1.00,  p = 0.30
                                                                                                              L02:1.01,p = 0.29
                                                                                                              Shortness of Breath
                                                                                                              L0:1.01,p = 0.01
                                                                                                              L1:1.00,  p = 0.56
                                                                                                              L2:1.00,  p = 0.60
                                                                                                              L02:1.03, p = 0.05
                                                                                                              Chest Tightness
                                                                                                              L0:1.00,  p = 0.34
                                                                                                              L1:1.00,  p = 0.55
                                                                                                              L2:0.99,  p = 0.49
                                                                                                              L02:1.01,p = 0.52
                                                                                                              Inhaler Use
                                                                                                              L0:1.00,  p = 0.72
                                                                                                              L1:1.00,  p = 0.30
                                                                                                              L2:1.00,  p = 0.67
                                                                                                              L02:1.00, p = 0.66
    
                                                                                                              Source: Sulfur
                                                                                                              S, Increments000ng/m3
                                                                                                              Wheeze
                                                                                                              L0:0.98,  p = 0.43
                                                                                                              L1:0.99,  p = 0.62
                                                                                                              L2:1.02,  p = 0.29
                                                                                                              L02:1.00, p = 0.99
                                                                                                              Persistent Cough
                                                                                                              L0:1.00,  p = 0.84
                                                                                                              L1:1.00,  p = 0.69
                                                                                                              L2:1.02,  p = 0.21
                                                                                                              L02:1.02, p = 0.27
                                                                                                              Shortness of Breath
                                                                                                              L0:1.01,p = 0.63
                                                                                                              L1:0.99,  p = 0.71
                                                                                                              L2:1.01,p = 0.55
                                                                                                              L02:1.01,p = 0.79
                                                                                                              Chest Tightness
                                                                                                              L0:0.99,  p = 0.80
                                                                                                              L1:1.01,p = 0.62
    December 2009                                                   E-189
    

    -------
                  Study                       Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                               L2:1.01, p = 0.81
                                                                                                               L02:1.02, p = 0.68
                                                                                                               Inhaler Use
                                                                                                               L0:0.99, p = 0.13
                                                                                                               L1:1.00, p = 0.81
                                                                                                               L2:1.02, p = 0.04
                                                                                                               L02:1.00, p = 0.81
    
                                                                                                               P, lncrement = 50ng/m3
                                                                                                               Wheeze
                                                                                                               L0:0.98, p = 0.39
                                                                                                               L1:0.98, p = 0.48
                                                                                                               L2:1.02, p = 0.38
                                                                                                               L02:0.99, p = 0.89
                                                                                                               Persistent Cough
                                                                                                               L0:1.00, p = 0.75
                                                                                                               L1:0.99, p = 0.69
                                                                                                               L2:1.01,p = 0.38
                                                                                                               L02:1.03, p = 0.30
                                                                                                               Shortness of Breath
                                                                                                               L0:1.01,p = 0.61
                                                                                                               L1:0.99, p = 0.71
                                                                                                               L2:1.01,p = 0.67
                                                                                                               L02:1.01,p = 0.78
                                                                                                               Chest Tightness
                                                                                                               L0:1.00, p = 0.88
                                                                                                               L1:1.01,p = 0.72
                                                                                                               L2:1.00, p = 0.87
                                                                                                               L02:1.02, p = 0.67
                                                                                                               Inhaler Use
                                                                                                               L0:0.98, p = 0.15
                                                                                                               L1:1.00, p = 0.83
                                                                                                               L2:1.01,p = 0.11
                                                                                                               L02:1.00, p = 0.99
    
                                                                                                               Source: Biomass Burning
                                                                                                               K, Increment = 50  ng/m3
                                                                                                               Wheeze
                                                                                                               L0:0.98, p = 0.06
                                                                                                               L1:0.99, p = 0.43
                                                                                                               L2:1.00, p = 0.85
                                                                                                               L02:0.96, p = 0.04
                                                                                                               Persistent Cough
                                                                                                               L0:1.00, p = 0.64
                                                                                                               L1:1.00, p = 0.83
                                                                                                               L2:1.00, p = 0.46
                                                                                                               L02:1.00, p = 0.86
                                                                                                               Shortness of Breath
                                                                                                               L0:1.01,p = 0.01
                                                                                                               L1:0.98, p = 0.09
                                                                                                               L2:1.00, p = 0.38
                                                                                                               L02:1.00, p = 0.79
                                                                                                               Chest Tightness
                                                                                                               L0:1.00, p = 0.02
                                                                                                               L1:0.99, p = 0.24
                                                                                                               L2:0.98, p = 0.07
                                                                                                               L02:0.99, p = 0.67
                                                                                                               Inhaler Use
                                                                                                               L0:1.00, p = 0.68
                                                                                                               L1:0.99, p = 0.05
                                                                                                               L2:1.00, p = 0.59
                                                                                                               L02:0.99, p = 0.28
    
                                                                                                               Source: Oil
                                                                                                               V, lncrement= 10 ng/m
                                                                                                               Wheeze
                                                                                                               L0:0.99, p = 0.73
                                                                                                               L1:0.96, p = 0.03
                                                                                                               L2:0.99, p = 0.56
                                                                                                               L02:0.93, p = 0.04
                                                                                                               Persistent Cough
                                                                                                               L0:1.01,p = 0.56
                                                                                                               L1:0.99, p = 0.24
                                                                                                               L2:0.98, p = 0.01
                                                                                                               L02:0.96, p = 0.05
                                                                                                               Shortness of Breath
                                                                                                               L0:1.01,p = 0.46
                 	L1:0.98, p = 0.24	
    December 2009                                                   E-190
    

    -------
                  Study                       Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                               L2:1.00, p = 0.83
                                                                                                               L02:0.98, p = 0.58
                                                                                                               Chest Tightness
                                                                                                               L0:0.99, p = 0.71
                                                                                                               L1:0.98, p = 0.32
                                                                                                               L2:0.98, p = 0.23
                                                                                                               L02:0.94, p = 0.12
                                                                                                               Inhaler Use
                                                                                                               L0:0.98, p = 0.12
                                                                                                               L1:1.00, p = 0.68
                                                                                                               L2:0.99, p = 0.22
                                                                                                               L02:0.96, p = 0.03
    
                                                                                                               Ni, Increment = 5 ng/m3
                                                                                                               Wheeze
                                                                                                               L0:1.01,p = 0.59
                                                                                                               L1:0.97, p = 0.09
                                                                                                               L2:1.00, p = 0.76
                                                                                                               L02:0.99, p = 0.72
                                                                                                               Persistent Cough
                                                                                                               LO: 1.01, p = 0.21
                                                                                                               L1:0.99, p = 0.57
                                                                                                               L2:0.99, p = 0.23
                                                                                                               L02:1.00, p = 0.99
                                                                                                               Shortness of Breath
                                                                                                               L0:1.04, p = 0.05
                                                                                                               L1:0.98, p = 0.36
                                                                                                               L2:1.00, p = 0.81
                                                                                                               L02:1.04, p = 0.32
                                                                                                               Chest Tightness
                                                                                                               L0:1.01,p = 0.58
                                                                                                               L1:1.00, p = 0.89
                                                                                                               L2:0.98, p = 0.27
                                                                                                               L02:1.01,p = 0.84
                                                                                                               Inhaler Use
                                                                                                               L0:1.01,p = 0.48
                                                                                                               L1:1.00, p = 0.83
                                                                                                               L2:0.99, p = 0.51
                                                                                                               L02:1.01,p = 0.48
    
                                                                                                               Source: Sea Salt
                                                                                                               Na, Increment = 100 ng/m3
                                                                                                               Wheeze
                                                                                                               L0:0.98, p = 0.23
                                                                                                               L1:1.00, p = 0.80
                                                                                                               L2:1.00, p = 0.88
                                                                                                               L02:0.97, p = 0.29
                                                                                                               Persistent Cough
                                                                                                               L0:1.00, p = 0.58
                                                                                                               L1:0.99, p = 0.19
                                                                                                               L2:1.00, p = 0.61
                                                                                                               L02:0.98, p = 0.21
                                                                                                               Shortness of Breath
                                                                                                               L0:1.00, p = 0.94
                                                                                                               L1:0.99, p = 0.46
                                                                                                               L2:1.01,p = 0.63
                                                                                                               L02:0.99, p = 0.74
                                                                                                               Chest Tightness
                                                                                                               L0:0.99, p = 0.43
                                                                                                               L1:0.99, p = 0.75
                                                                                                               L2:1.00, p = 0.88
                                                                                                               L02:0.98, p = 0.61
                                                                                                               Inhaler Use
                                                                                                               L0:0.99, p = 0.35
                                                                                                               L1:1.00, p = 0.61
                                                                                                               L2:1.00, p = 0.85
                                                                                                               L02:0.99, p = 0.37
    
                                                                                                               Cl, Increment = 10 ng/m3
                                                                                                               Wheeze
                                                                                                               L0:1.00, p = 0.89
                                                                                                               L1:1.00, p = 0.88
                                                                                                               L2:1.00, p = 0.38
                                                                                                               L02:1.00, p = 0.81
                                                                                                               Persistent Cough
                                                                                                               L0:1.00, p = 0.31
                                                                                                               L1:1.00, p = 0.31
                 	L2:1.00, p = 0.51	
    December 2009                                                    E-191
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                  L02:1.00, p = 0.06
                                                                                                                  Shortness of Breath
                                                                                                                  L0:1.00, p = 0.89
                                                                                                                  L1:1.00, p = 0.94
                                                                                                                  L2:1.00, p = 0.70
                                                                                                                  L02:1.00, p = 0.80
                                                                                                                  Chest Tightness
                                                                                                                  L0:1.00, p = 0.24
                                                                                                                  L1:1.00, p = 0.28
                                                                                                                  L2:1.00, p = 0.52
                                                                                                                  L02:1.00, p = 0.65
                                                                                                                  Inhaler Use
                                                                                                                  L0:1.00, p = 0.69
                                                                                                                  L1:1.00, p = 0.52
                                                                                                                  L2:1.00, p = 0.51
                                                                                                                  L02:1.00, p = 0.83
    
                                                                                                                  Odds Ratio (96%CI) from repeated
                                                                                                                  measures logistic regression models
                                                                                                                  of respiratory symptoms and daily
                                                                                                                  source concentrations of PMu.
                                                                                                                  Lag 0 Model
                                                                                                                  Wheeze, p = 0.23
                                                                                                                  Motor Vehicle:  1.05 (0.99-1.10)
                                                                                                                  Road Dust: 1.10 (1.01-1.19)
                                                                                                                  Sulfur: 0.97 (0.94-1.00)
                                                                                                                  Biomass Burning: 0.80 (0.66-0.98)
                                                                                                                  011:1.02(0.86-1.20)
                                                                                                                  Sea Salt: 0.96  (0.86-1.07)
    
                                                                                                                  Persistent Cough, p < 0.001
                                                                                                                  Motor Vehicle:  1.02 (0.99-1.04)
                                                                                                                  Road Dust: 1.06 (1.01-1.11)
                                                                                                                  Sulfur: 1.00 (0.98-1.01)
                                                                                                                  Biomass Burning: 0.97 (0.92-1.03)
                                                                                                                  011:1.02(0.95-1.10)
                                                                                                                  Sea Salt: 0.99  (0.92-1.07)
    
                                                                                                                  Shortness of Breath, p< 0.001
                                                                                                                  Motor Vehicle:  1.06 (1.01-1.11)
                                                                                                                  Road Dust: 1.12 (1.02-1.22)
                                                                                                                  Sulfur: 0.98 (0.94-1.02)
                                                                                                                  Biomass Burning: 1.05 (0.95-1.17)
                                                                                                                  011:1.07(0.92-1.26)
                                                                                                                  Sea Salt: 1.01  (0.92-1.12)
    
                                                                                                                  Chest Tightness, p < 0.001
                                                                                                                  Motor Vehicle:  1.02 (0.97-1.08)
                                                                                                                  Road Dust: 1.04 (0.95-1.15)
                                                                                                                  Sulfur: 0.99 (0.94-1.03)
                                                                                                                  Biomass Burning: 1.06 (0.95-1.18)
                                                                                                                  011:0.99(0.82-1.18)
                                                                                                                  Sea Salt: 0.95  (0.84-1.08)
    
                                                                                                                  Inhaler Use, p  < 0.001
                                                                                                                  Motor Vehicle:  1.02 (1.00-1.05)
                                                                                                                  Road Dust: 1.06 (1.02-1.11)
                                                                                                                  Sulfur: 0.98 (0.97-1.00)
                                                                                                                  Biomass Burning: 1.00 (0.96-1.03)
                                                                                                                  011:0.98(0.91-1.05)
                                                                                                                  Sea Salt: 0.99  (0.94-1.04)
    
                                                                                                                  Lag 02 Model
                                                                                                                  Wheeze, p = 0.86
                                                                                                                  Motor Vehicle:  1.10(1.01-1.19)
                                                                                                                  Road Dust: 1.26 (1.05-1.51)
                                                                                                                  Sulfur: 0.98 (0.92-1.04)
                                                                                                                  Biomass Burning: 0.64 (0.46-0.88)
                                                                                                                  011:0.80(0.56-1.08)
                                                                                                                  Sea Salt: 0.91  (0.82-1.16)
    
                                                                                                                  Persistent Cough, p < 0.001
                                                                                                                  Motor Vehicle:  1.03 (0.98-1.09)
                                                                                                                  Road Dust: 1.16 (1.02-1.32)
                                                                                                                  Sulfur: 1.01 (0.98-1.05)
                                                                                                                  Biomass Burning: 0.93 (0.81-1.06)
                                                                                                                  011:0.84(0.71-1.00)
                 	Sea Salt: 0.88  (0.77-1.01)	
    December 2009                                                     E-192
    

    -------
                  Study                        Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
    
                                                                                                                 Shortness of Breath, p = 0.006
                                                                                                                 Motor Vehicle: 1.12 (1.01-1.24)
                                                                                                                 Road Dust:  1.28 (1.05-1.55)
                                                                                                                 Sulfur: 0.97 (0.90-1.04)
                                                                                                                 Biomass Burning: 0.78 (0.52-1.18)
                                                                                                                 011:0.94(0.69-1.29)
                                                                                                                 Sea Salt:  1.01 (0.79-1.29)
    
                                                                                                                 Chest Tightness, p = 0.39
                                                                                                                 Motor Vehicle: 1.08 (0.98-1.20)
                                                                                                                 Road Dust:  1.20 (0.97-1.49)
                                                                                                                 Sulfur: 1.00 (0.92-1.08)
                                                                                                                 Biomass Burning: 0.87 (0.62-1.22)
                                                                                                                 011:0.80(0.58-1.10)
                                                                                                                 Sea Salt:  0.95 (0.71-1.27)
    
                                                                                                                 Inhaler Use, p < 0.001
                                                                                                                 Motor Vehicle: 1.03 (0.98-1.08)
                                                                                                                 Road Dust:  1.09 (1.00-1.19)
                                                                                                                 Sulfur: 1.00 (0.97-1.03)
                                                                                                                 Biomass Burning: 0.95 (0.87-1.04)
                                                                                                                 011:0.92(0.81-1.05)
                                                                                                                 Sea Salt:  0.97 (0.88-1.07)
    
                                                                                                                 Odds Ratio (96%CI) from repeated
                                                                                                                 measures logistic regression models
                                                                                                                 of respiratory symptoms and daily
                                                                                                                 source concentrations of PMu when
                                                                                                                 copollutants are included.
    
                                                                                                                 Wheeze
                                                                                                                 Motor Vehicle
                                                                                                                 N02:1.03 (0.98-1.08)
                                                                                                                 00:1.05(0.99-1.11)
                                                                                                                 S02:1.04 (0.99-1.09)
                                                                                                                 03:1.06 (0.97-1.16)
                                                                                                                 Road Dust
                                                                                                                 N02:1.11 (1.02-1.20)
                                                                                                                 00:1.10(1.01-1.19)
                                                                                                                 S02:1.10 (1.01-1.19)
                                                                                                                 03:1.11 (1.01-1.23)
                                                                                                                 Sulfur
                                                                                                                 N02: 0.96 (0.92-0.99)
                                                                                                                 00:0.97(0.94-1.01)
                                                                                                                 S02: 0.97 (0.93-1.00)
                                                                                                                 03: 0.95 (0.91-1.00)
                                                                                                                 Biomass Burning
                                                                                                                 N02: 0.79 (0.65-0.98)
                                                                                                                 CO: 0.80  (0.66-0.98)
                                                                                                                 S02: 0.79 (0.64-0.98)
                                                                                                                 03: 0.74 (0.57-0.97)
                                                                                                                 Oil
                                                                                                                 N02:1.02 (0.87-1.21)
                                                                                                                 00:1.02(0.86-1.20)
                                                                                                                 S02:1.01 (0.86-1.19)
                                                                                                                 03: 0.92 (0.62-1.39)
                                                                                                                 Sea Salt
                                                                                                                 N02: 0.96 (0.85-1.07)
                                                                                                                 00:0.96(0.86-1.08)
                                                                                                                 S02: 0.95 (0.85-1.07)
                                                                                                                 03:1.01 (0.72-1.40)
    
                                                                                                                 Inhaler Use
                                                                                                                 Motor Vehicle
                                                                                                                 N02:1.02 (0.99-1.04)
                                                                                                                 00:1.02(0.99-1.05)
                                                                                                                 S02:1.02 (0.99-1.04)
                                                                                                                 03:1.02 (0.98-1.07)
                                                                                                                 Road Dust
                                                                                                                 N02:1.06 (1.02-1.10)
                                                                                                                 00:1.06(1.02-1.11)
                                                                                                                 S02:1.06 (1.02-1.11)
                                                                                                                 03:1.06 (1.00-1.13)
                                                                                                                 Sulfur
                                                                                                                 N02: 0.98 (0.96-1.00)
                                                                                                                 00:0.98(0.96-1.00)
                 	S02: 0.98 (0.96-1.00)	
    December 2009                                                     E-193
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                                                               03: 0.97 (0.95-1.00)
                                                                                                               Biomass Burning
                                                                                                               N02:1.00 (0.96-1.03)
                                                                                                               00:0.99(0.96-1.03)
                                                                                                               S02: 0.99  (0.96-1.03)
                                                                                                               03: 0.99 (0.95-1.03)
                                                                                                               Oil
                                                                                                               N02: 0.98 (0.91-1.05)
                                                                                                               00:0.97(0.91-1.04)
                                                                                                               S02: 0.97  (0.91-1.04)
                                                                                                               03:1.03 (0.88-1.22)
                                                                                                               Sea Salt
                                                                                                               N02: 0.99 (0.94-1.04)
                                                                                                               00:0.99(0.94-1.04)
                                                                                                               S02: 0.99  (0.94-1.04)
                                                                                                               03:1.01 (0.88-1.15)
    Reference: Girardot et al. (2006,
    0882711
    
    Period of Study:
    Aug 2002-Oct 2002
    
    Jun 2003-Aug 2003
    Outcome: Pulmonary
    function/spirometry-FVC, FEV,, PEF,
    FVC/FEV,, FEF25-75
    
    Age Groups: 18-82yr
    
    Study Design: Cohort
    Location: Charlies Bunion Trail (portion  N: 354 hikers
    of Appalachia Trail)
                                        Statistical Analyses: Multiple linear
                                        regression
    
                                        Covariates: Age, h hiked, mean
                                        temperature, sex, smoking status,
                                        history of asthma or wheeze symptoms,
                                        carriage of backpack, whether reaching
                                        summit or not
    
                                        Season: Fall 2002, Summer 2003
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: SAS
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean:
    
    Trail: 13.9 ±8.2
    
    Estimated personal: 15.0 ± 7.4
    
    Range (Min, Max):
    
    Trail: 1.6, 38.4
    
    Estimated personal:
    
    0.21,41.9
    
    Copollutant (correlation): 0; (i-u.67.
    for estimated personal exposure)
    PM Increment: 1  pg/m
    % Change ± Cl
    p value
    Univariate:
    FVC: 0.023 ± 0.035
    0.51
    FEV,: 0.015 ±0.029
    0.607
    PEF: 0.185 ±0.091
    0.043
    FVC/FEV,: 0.003  ±0.023
    0.905
    FEF25-75%: 0.052 ± 0.093
    0.578
    Adjusted: FVC: 0.007+/0.040
    0.966
    FEV,: 0.003 ±0.033
    0.937
    PEF: 0.258 ±0.103
    0.013
    FVC/FEV,:-0.011 ±0.027
    0.676
    FEF25-75%:-0.041 ±0.109
    0.707
    Spirometry result for each quintile ± Cl
    Quintile 1 (6.0 pg/m3): FVC (L):
    Prehike: 4.32 ±0.13
    Posthike:4.33±0.12
    FEV,(L): Prehike: 3.39 ±0.10
    Posthike:3.40±0.10
    FEV,/FVC (%): Prehike: 78.66 ± 0.86
    Posthike: 78.63 ±  0.81
    FEF25-75% (L/sec): Prehike:  3.27 ±
    0.14
    Posthike: 3.26 ±0.14
    PEF (L/sec): Prehike: 7.91+/0.22
    Posthike: 7.58 ±0.22
    Quintile 2 (10.4 pg/m3): FVC  (L):
    Prehike: 4.30 ±0.11
    Posthike: 4.30 ±0.11
    FEV, (L): Prehike: 3.42 ± 0.09
    Posthike: 3.43 ±0.09
    FEV,/FVC (%): Prehike: 79.37 ± 0.71
    Posthike: 79.55 ±  0.69
    FEF25-75% (L/sec): Prehike:  3.39 ±
    0.14
    Posthike: 3.38 ±0.14
    PEF (L/sec): Prehike: 8.37+/0.23
    Posthike: 8.26 ±0.25
    Quintile 3 (14.8 pg/m3): FVC  (L):
    Prehike: 4.34 ±0.12
    Posthike: 4.33 ±0.12
    FEV, (L): Prehike: 3.42 ±0.10
    Posthike: 3.40 ±0.09
    FEV,/FVC (%): Prehike: 79.20 ± 0.81
    Posthike: 78.83 ±0.80
    FEF25-75% (L/sec): Prehike:  3.19 ±
    0.13
    Posthike: 3.21 ±0.13
    PEF (L/sec): Prehike: 8.12+/0.25
    Posthike: 7.89 ±0.25
    Quintile 4 (17.9 |jg/m3):	
    December 2009
                                    E-194
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                                                                FVC(L):Prehike: 4.23 ±0.11
                                                                                                                Posthike: 4.23 ±0.11
                                                                                                                FEV, (L): Prehike: 3.36 ±0.10
                                                                                                                Posthike: 3.36 ±0.10
                                                                                                                FEV,/FVC (%): Prehike: 79.18 ± 0.81
                                                                                                                Posthike: 79.26 ±0.79
                                                                                                                FEF25-75% (L/sec): Prehike: 3.34 ±
                                                                                                                0.15
                                                                                                                Posthike: 3.30 ±0.15
                                                                                                                PEF (L/sec): Prehike: 7.75+/0.25
                                                                                                                Posthike: 7.73 ±0.26
                                                                                                                Quintile6(26.6|jg/m3):FVC(L):
                                                                                                                Prehike: 4.15 ±0.11
                                                                                                                Posthike: 4.18 ±0.12
                                                                                                                FEV, (L): Prehike: 3.31 ± 0.09
                                                                                                                Posthike: 3.33 ±0.10
                                                                                                                FEV,/FVC (%): Prehike: 79.73 ± 0.66
                                                                                                                Posthike: 79.55 ±0.64
                                                                                                                FEF25-75% (L/sec): Prehike: 3.22 ±
                                                                                                                0.14
                                                                                                                Posthike: 3.24 ±0.14
                                                                                                                PEF (L/sec): Prehike: 7.72+/0.22
                                                                                                                Posthike: 7.77 ± 0.23
                                                                                                                Overall (16.0 pg/m3): FVC (L): Prehike:
                                                                                                                4.27 ± 0.05
                                                                                                                Posthike: 4.27 ± 0.05
                                                                                                                FEV,(L): Prehike: 3.38 ±0.04
                                                                                                                Posthike: 3.38 ±0.04
                                                                                                                FEV,/FVC (%): Prehike: 79.2 ± 0.34
                                                                                                                Posthike: 79.2 ± 0.33
                                                                                                                FEF25-75% (L/sec): Prehike: 3.28 ±
                                                                                                                0.06
                                                                                                                Posthike: 3.28 ±0.06
                                                                                                                PEF (L/sec): Prehike: 7.97+/0.11
                                                                                                                Posthike: 7.97 ±0.11
    Reference: Hertz-Picciotta et al. (2007,
    1359171
    
    Period of Study: 1994-2003
    
    Location: Teplice and Prachatice,
    Czech Republic
    Outcome: Lower respiratory
    illness-croup (JOS, J04), acute
    bronchitis (J20), acute bronchiolitis
    (J21)
    
    Age Groups: Neonates followed for
    2-4. Syr
    
    Study Design: Cohort
    
    N: 1133 children
    
    Statistical Analyses: Generalized
    linear longitudinal models
    
    Covariates:  District, mother's age,
    mother's education, mother or adult
    smoke, child's sex, season, day of the
    week, fuel  for heating and/or cooking,
    breastfeeding category, number of other
    children, temperature
    
    Season: Winter, spring, summer and
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD):
    
    PAH: 22.3 (SD-16 for 3-day avg and 11
    for 45-day avg)
    PM Increment: 25 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Birth-23 mo:
    1.30 [1.08, 1.58] lag 1-30
    2-4.5 yr:
    1.23 [0.94, 1.62] lag 1-30
    RR Estimate for categories of
    exposure [Lower Cl, Upper Cl] lag:
    Crude RR:
    Birth-23 mo:
    > 50 pg/m3: 2.26 [1.81, 2.82] lag 1-30
    25-50 pg/m3:1.48 [1.32,1.65] lag 1-30
    < 25 pg/m3:
    Referent
    2-4.5 yr:
    > 50 pg/m3: 3.66 [2.07, 6.48] lag 1-30
    25-50 pg/m3:1.60 [1.41,1.82] lag 1-30
    < 25 pg/m3:
    Referent
                                        Dose-response Investigated? No
    
                                        Statistical Package: SUDAAN version
                                        Lags Considered: 1-3,1-7,1-14,1-30,
                                        1-45
    December 2009
                                    E-195
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Hertz- Picciotta et al.
    (2007, 1359171
    Period of Study: 1994-2003
    Location: Teplice and Prachatice,
    Czech Republic
    Outcome: Lower respiratory
    illness-croup (JOS, J04), acute
    bronchitis (J20), acute bronchiolitis
    (J21)
    Age Groups: Neonates followed for
    2-4. Syr
    Study Design: Cohort
    N: 1133 children
    Statistical Analyses: Generalized
    linear longitudinal models
    Covariates:  District, mother's age,
    mother's education, mother or adult
    smoke, child's sex, season, day of the
    week, fuel  for heating and/or cooking,
    breastfeeding category, number of other
    children, temperature
    Dose-response Investigated? No
    Statistical Package: SUDAAN version
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD):
    PAH:
    52.5 ng/m3 (SD-57 ng/m3 for 3-day avg
    and 46 ng/m3 for 45-day avg)
    PAH Increment: 100 ng/m
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Birth-23 mos:
    1.29 [1.07, 1.54] lag 1-30
    2-4.5 yr:
    1.56 [1.22, 2.00] lag 1-30
    RR Estimate for categories of exposure
    [Lower Cl, Upper Cl] lag:
    Crude RR:
    Birth-23 mos:
    > 100 ng/m3: 2.52 [2.22, 2.87] lag 1-30
    40-100 ng/m3:1.87 [1.65, 2.13] lag 1-30
    < 40 ng/m3: Reference
    2-4.5 yr:
    > 100 ng/m3: 2.26 [1.93, 2.65] lag 1-30
    40-100 ng/m3:1.40 [1.20,1.64] lag 1-30
    < 40 ng/m3: Reference
                                        Lags Considered: 1-3,1-7,1-14,1-30,
                                        1-45
    Reference: Hogervorst, et al. (2006,
    A ccccn\
    1bbbb9)
    Period of Study: 2002
    
    Location: Maastricht, the Netherlands
    (six schools selected)
    
    
    
    
    Outcome: Decreased lung function
    Age Groups: 8-1 Syr
    
    Study Design: Multivariate linear
    regression (enter method) analysis
    N: 342 children
    
    Statistical Analyses: ANOVA, chi
    square
    Covariates: Independent variables:
    Pollutant: PM25
    Averaging Time: Daily
    
    Mean (SD): 19.0 (3.2)
    Monitoring Stations: 6
    
    Co pollutant:
    PM10
    Total Suspended Particles (TSP)
    PM Increment: 10 pg/m3
    RR Estimate [Lower Cl, Upper Cl]
    
    lag:
    FEV: 3.62 [0.50,7.63] lag NR
    
    FVC: 1.80 [-2.10, 5.80] lag NR
    FEF: 5.93 [-2.34, 14.89] lag NR
    
                                        Age, height, gender, smoking at home
                                        by parents, pets, use of ventilation
                                        hoods during cooking,  presence of
                                        unvented geysers, tapestry in the
                                        home, indoor/outdoor time, education
                                        level of parents.
                                        Dependent variables: lung function
                                        indices
                                        Dose-response Investigated? No
    Reference: Holguin et al, (2007,
    0990001
    Period of Study:
    Location: Ciudad Juarez, Mexico
    Outcome: FeNO, FEV,
    Study Design: Panel
    Covariates: sex, age, body mass
    index, day of week, season, yr of
    maternal and paternal education,
    passive smoking
    Statistical Analysis: linear and
    nonlinear mixed effects models
    Age Groups: 6-12 yr
    Pollutant: PM25
    Averaging Time: 48 h
    Mean (SD) Unit: 17.5 (8.9) pg/m3
    Range (Min, Max): NR
    Copollutant (correlation): NR
    Increment: NR
    Relative Risk (Min Cl, Max Cl)
    Lag
    Results not given in table form, but
    abstract states that no significant
    associations with PM25 were observed.
    December 2009
                                    E-196
    

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                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Hong et al. (2007, 0913471  Outcome: Peak expiratory flow rate
    
    Period of Study: Mar 23-May 2004     '      '
                                       Age Groups: 3rd-6th grade (mean
    Location: School on the Dukjeok Island  age=9.6 yr)
    near Incheon City, Korea
                                       Study Design: Panel study
    
                                       N: 43 schoolchildren
    
                                       Statistical Analyses: Mixed linear
                                       regression
    
                                       Covariates: age, sex, height, weight,
                                       asthma history, and passive smoking
                                       exposure at home
    
                                       Dose-response Investigated? No
    
                                       Lags Considered :0,1,2,3,4,5
                                       Pollutant: PM25
    
                                       Averaging Time: 24 h
    
                                       Mean (SD): 20.27 (8.23)
    
                                       SOth(Median): 22.07
    
                                       Range (Min, Max): 5.94-36.28
    
                                       Co pollutant:
                                       PM10
    
                                       Components of PM10
                                       (Fe, Mn, Pb.Zn.AI)
                                       Effect Estimate:
    
                                       Regression coefficients of morning and
                                       daily mean PEFR on PM25
                                       Lag 1 (PM25)
                                       Morning PEFR
                                       Crude:  B=-0.14, p=0.12
                                       Adjusted: IS= -0.54, p,0.01
                                       Mean PEFR
                                       Crude:  IS= -0.15, p=0.02
                                       Adjusted: IS= -0.54, p,0.01
                                       Regression coefficients of morning and
                                       daily mean PEFR on PM25 and GSTM1
                                       and GSTT1 genotype using linear
                                       mixed-effects regression
                                       Lag 1 (PM25)
                                       Morning PEFR: IS= -0.57, p < 0.01
                                       Mean PEFR: IS= -0.56, p  < 0.01
                                       GSTM1
                                       Morning PEFR: IS= 20.04, p=0.25
                                       Mean PEFR: IS= 18.75, p=0.28
                                       GSTT1
                                       Morning PEFR: IS= 2.31,  p=0.89
                                       Mean PEFR: S=1.75, p=0.91	
    Reference: Jansen, et al. (2005,
    0822361
    
    Period of Study: 1987-2000
    
    Location: Seattle, WA
    Outcome: FENO: fractional exhaled
    nitrogen oxide, Spirometry, Blood
    pressure,  Sa02: oxygen saturation,
    Pulse rate
    
    Age Groups: 60-86-yr-old
    
    Study Design: Short-term cross-
    sectional case series
    
    N: 16 subjects diagnosed with COPD,
    asthma, or both
    
    Statistical Analyses: Linear mixed
    effects model with random intercepts
    
    Covariates: Age, relative humidity,
    temperature, medication use
    
    Season: Winter 2002-2003
    
    Dose-response Investigated? No
    
    Statistical Package: STATA
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD):
    
    Fixed-Site Monitor: 14.0
    All Subjects (N=16)
    Indoor, home: 7.29
    Outdoor, home: 10.47
    Asthmatic Subjects (N=7)
    Indoor, home: 7.25
    Outdoor, home: 8.99
    COPD Subjects (N=9)
    Indoor, home: 7.33
    Outdoor, home: 11.66
    Range (Min, Max):
    
    Fixed-Site Monitor: 1.3, 44
    IQR
    All Subjects
    Indoor, home: 4.05
    Outdoor, home: 8.87
    Asthmatic Subjects
    Indoor, home: 5.72
    Outdoor, home: 7.55
    COPD Subjects
    Indoor, home: (3.18
    Outdoor, home: 6.71
    PM Increment: PM25:10 |ig/m
    
    Slope [95% Cl]: dependence of FENO
    concentration [ppb] on PM25
    
    Asthmatic Subjects
    
    Indoor, home: 3.69 [-0.74: 8.12]
    
    Outdoor, home: 4.23 [1.33: 7.13]*
    
    Copd Subjects
    
    Indoor, home: -0.35 [-7.45: 6.75]
    
    Outdoor, home: 3.83 [-1.84: 9.49]
    
    Results indicate that FENO may be a
    more sensitive biomarker of PM
    exposure than other traditional health
    endpoints.
    December 2009
                                    E-197
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Johnston, et al. (2006,
    0913861
    Period of Study: 7 mo
    (Apr-Nov 2004)
    
    Location: Darwin, Australia
    Outcome: Asthma symptoms
    
    Age Groups: All Ages
    
    Study Design: Time-series
    
    N: 251 people
    
    (130 adults, 121 children
    
    Statistical Analyses: Logistic
    regression model
    
    Covariates: Minimum air temperature,
    doctor visits for influenza and the
    prevalence of asthma symptoms and,
    the fungal spore count and both onset
    of asthma symptoms and
    commencement of reliever medication
    
    Season: "Dry season"- note Southern
    Hemisphere
    
    Dose-response Investigated? No
    
    Statistical Package: STATA8
    
    Lags Considered: 0-5  days
    Pollutant: PM25
    
    Averaging Time: Daily
    
    Mean (SD): 11.1(5.4)
    
    Range (Min, Max): 2.2, 36.5
    
    PM Component: Vegetation fire smoke
    (95%) and motor vehicle emissions
    (5%)
    
    Monitoring Stations: 1
    PM Increment: 5 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Symptoms attributable to asthma
    Overall: 1.000 (0.98,1.01)
    Adults: 1.000 (0.976,1.026)
    Children:  1.008 (0.980,1.037)
    Using preventer: 1.013 (0.990,1.037)
    Became symptomatic
    Overall: 1.150 (1.07,1.23)
    Adults: 1.165 (1.058,1.284)
    Children:  1.148 (1.042,1.264)
    Using preventer: 1.181  (1.076,1.296)
    Used Reliever
    Overall: 1.000 (0.98,1.02)
    Adults: 1.007 (0.980, 1.035)
    Children:  1.002 (0.972,1.034)
    Using preventer: 1.020 (1.000,1.042)
    Commenced Reliever
    Overall: 1.120 (1.03,1.210)
    Adults: 1.141 (1.021, 1.275)
    Children:  1.112 (0.994,1.243)
    Using preventer: 1.129 (1.013,1.257)
    Commenced Oral Steroids
    Overall: 1.310 (103,1.66)
    Adults: 1.601 (1.192,2.150)
    Children:  0.995 (0.625,1.459)
    Using preventer: 1.350 (1.040,1.752)
    Asthma Attack
    Overall: 0.980 (0.94,1.04)
    Adults: 1.026 (0.962, 1.095)
    Children:  0.832 (0.731, 0.946)
    Using preventer: 1.002 (0.934,1.075)
    Exercise induced asthma
    Overall: 0.990 (0.95,1.03)
    Adults: 0.998 (0.943, 1.056)
    Children:  0.982 (0.899,1.071)
    Using preventer: 1.002 (0.942,1.067)
    Saw a health professional for asthma
    Overall: 1.030 (0.91,1.16)
    Adults: 1.079 (0.899, 1.296)
    Children:  1.003 (0.841,1.195)
    Using preventer: 0.980 (0.847,1.133)
    Missed school or work due to
    asthma
    Overall: 1.025 (0.9284,1.131)
    Adults: 1.077 (0.923, 1.247)
    Children:  1.000 (0.873,1.458)
    Using preventer: 1.005 (0.897,1.124)
    Mean daily number of asthma
    symptoms
    Overall: 1.003 (0.99,1.01)
    Adults: 0.998 (0.984, 1.012)
    Children:  1.004 (0.985,1.023)
    Using preventer: 1.013 (0.999,1.028)
    Mean Daily number of applications of
    reliever
    Overall: 1.002 (0.993,1.010)
    Adults: 1.001 (0.986, 1.016)
    Children:  1.000 (0.980,1.021)
    Using preventer: 1.005 (0.994,1.017)
    December 2009
                                    E-198
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Koenig et al. (2003,
    1566531
    Period of Study: Winter 2000-2001,
    Spring 2001
    Location: Seattle, WA
    Outcome: Exhaled NO (eNO)
    Age Groups: 6-1 Syr old
    Study Design: Cohort
    N: 19 children
    Statistical Analyses: Linear mixed-
    effects regression
    Covariates: Medication use, ambient
    NO reading for specific individual on
    specific day of session, mean ambient
    NO for subject during session, mean
    ambient NO for subject during all
    sessions
    Season: Winter, Spring
    Dose-response Investigated? No
    Statistical Package: STATA
    Pollutant: PM25
    Averaging Time: 10 consecutive days
    Mean (SD): Outdoor: 13.3(1.4)
    Indoor: 11.1 (4.9)
    Personal: 13.4 (3.2)
    Central-site: 10.1 (5.7)
    Range (Min, Max): Outdoor: Max: 40.4
    Indoor: Max: 36.3
    Personal: Max: 49.4
    Central-site: NR
    Monitoring Stations: Outdoor: NR
    Indoor: NR
    Personal: NR
    Central-site: 3
    Copollutant (correlation): Outdoor
    PM-central-site NO: 0.50
    For NO values < 100 ppb, outdoor PM-
    central-site NO: 0.04
    PM Increment: 10 pg/m
    Results presented as change in eNO
    (95% Cl)
    Among ICS* nonuser
    Personal monitor 4.48 (1.02, 7.93)
    Outdoor monitor 4.28 (1.38, 7.17)
    Indoor monitor 4.21 (1.02,7.41)
    Central site 3.82 (1.22, 6.43)
    Among ICS* user
    Personal monitor-0.09 (-2.39, 2.21)
    Outdoor monitor 0.74 (-2.28, 3.76)
    Indoor monitor-1.11 (-5.08,2.87)
    Central site 1.28 (-1.23, 3.79)
    * ICS: Inhaled corticosteroid
    Reference: Koenig et al. (2003,
    1566531
    
    Period of Study: Wnter 2000-2001,
    Spring 2001
    Location: Seattle, WA
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Increased exhaled nitric
    oxide (eNO)
    
    Age Groups: 6-13 yr of age
    Study Design: Combined recursive
    and predictive model
    N: 19 children with asthma
    
    Statistical Analyses: Linear mixed
    effects model
    
    Covariates: Residence type, air
    cleaner, avg outdoor temperature, avg
    daily rainfall
    Season: Wnter Spring
    
    Dose-response Investigated? No
    
    Statistical Package:
    STATA 7.0 for health analyses, SAS 8.0
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM25
    
    Averaging Time: Daily
    Mean: Home indoor 9.5
    Home outdoor 11.1
    Recursive model Bag: 7.0
    Recursive model Eig:2.1
    Predictive model Bag: 6.0
    Predictive model Eig: 4.0
    Combined model Bag: 6.4
    Combined model Eig: 3.2
    25th: Home indoor 5. 7
    Home outdoor 6.3
    Recursive model Bag: 4.2
    Recursive model Eig: 0.0
    Predictive model Bag: 3.4
    Predictive model Eig: 0.9
    Combined model Bag: 3.7
    Combined model Eig: 0.5
    60th(Median): Home indoor 7.6
    Home outdoor 9.5
    Recursive model Bag: 5.9
    Recursive model Eig: 1.2
    Predictive model Bag: 5.0
    Predictive model Eig: 2.2
    Combined model Bag: 5.5
    Combined model Eig: 1.7
    76th: Home indoor 10.8
    Home outdoor 14.6
    Recursive model Bag: 9.2
    Recursive model Eig: 2.3
    Predictive model Bag: 7.5
    Predictive model Eig: 4.9
    Combined model Bag: 7.8
    Combined model Eig: 4.2
    PM Increment: 10-pg/m3
    
    RR Estimate [Lower Cl, Upper Cl]
    Ian1
    lag.
    Eag= ambient-generated personal
    exposure
    
    Eig= indoor-generated personal
    exposure
    
    eNO= exhaled nitric oxide
    Recursive model with 8 children, Eag
    was marginally associated with
    increases in eNO [5.6 ppb [-0.6,11.9].
    Eig was not associated with eNO (-0. 19
    ppb).
    
    For those combined estimates, only
    Eag was significantly associated with
    an increase in eNO:
    Eag: 5.0 ppb [0.3, 9.7]
    Eig: 3.3 ppb [1.1, 7.7]
    Notes: Effects were seen only in
    children who were not using
    corticosteroid therapy
    
    
    
    
    
    
                                                                           Range (Min, Max): Home indoor 2.3,
                                                                           36.3
                                                                           Home outdoor 2.8, 40.4
                                                                           Recursive Eag: 1.8,22.6
                                                                           Recursive Eig: 0.0,17.2
                                                                           Predictive Eag: 1.3,22.6
                                                                           Predictive Eig: 0.0,33.0
                                                                           Combined Eag: 1.3,22.6
                                                                           Combined Eig: 0.0,33.0
                                                                           Monitoring Stations: 19 personal
                                                                           environmental monitors
    December 2009
                                    E-199
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Kongtip et al. (2006,
    0969201
    
    Period of Study: Sep-Oct 2004
    
    Location: Dindang district, Bangkok
    metropolitan, Thailand
    Outcome: respiratory and other
    Outcomes reported
    
    Age Groups: Age range 15-55 yr
    
    Study Design: Panel study
    
    N: 77 street vendors
    
    Statistical Analyses: Binary logistic
    regression
    
    Covariates: Gender, age, type of fuel
    used, working duration (months)
    
    Dose-response Investigated? No
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD): 70.94
    
    Percentiles: SOth(Median): 72.05
    
    Range (Min, Max): 23.20-120.00
    
    Monitoring Stations: 1
    
    Copollutant (correlation):
    
    S02
    
    N02
    
    03
    
    VOCs
    
    CO
    PM Increment: 1 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Model 1
    Headache: 1.011 (0.999-1.022)
    Nose congestion: 1.006 (0.997-1.015)
    Sore throat: 1.000 (0.991-1.008)
    Cold: 1.006 (0.995-1.017)
    Cough: 0.989 (0.980-0.998)
    Phlegm: 0.998 (0.992-1.003)
    Chest tightness: 0.995 (0.955-1.036)
    Fever: 1.008 (0.993-1.024)
    Eye irritation: 1.022 (1.011-1.033)
    Dizziness: 1.027 (1.013-1.041)
    Weakness: 0.996 (0.983-1.008)
    Upper respiratory symptom: 1.001
    (0.994-1.008)
    Lower respiratory symptom: 0.997
    (0.992-1.002)
    Model 2
    Headache: 1.004 (0.996-1.013)
    Nose congestion: 1.003 (0.996-1.010)
    Sore throat: 0.995 (0.989-1.001)
    Cold: 0.996 (0.988-1.004)
    Cough: 0.990 (0.983-0.996)
    Phlegm: 0.995 (0.991-0.999)
    Chest tightness: 0.997 (0.970-1.025)
    Fever: 1.010 (0.998-1.022)
    Eye irritation: 1.019 (1.010-1.028)
    Dizziness: 1.020 (1.009-1.032)
    Weakness: 1.003 (0.994-1.012)
    Upper respiratory symptom: 0.995
    (0.990-1.000)
    
    Lower respiratory symptom: 0.995
    (0.991-0.999)
    Reference: Lagorio et al. (2006,
    0898001
    Period of Study:
    May-Jun1999 and Nov-Dec 1999
    Location: Rome, Italy
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Lung function (FVC and
    FEV,) of subjects with COPD, Asthma
    Age Groups: COPD 50-80 yr
    Asthma 18-64 yr
    Study Design: Time series
    N:COPD= 11
    Asthma = 11
    Statistical Analyses: Non-parametric
    Spearman correlation
    GEE
    
    Covariates: COPD and IHD: daily
    mean temperature, season variable
    (spring or winter), relative humidity, day
    of week
    Asthma: season variable, temperature,
    humidity, and (3-2-agonist use
    Season: Spring and Winter
    Dose-response Investigated? Yes
    Statistical Package: STATA
    
    Lags Considered: 1-3 days
    
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD):
    Overall: 27.2 (19.4)
    Spring: 18.2 (5.0)
    Winter: 36.7 (24.1)
    Range (Min, Max): 4.5, 100
    PM Component:
    Cd: 0.46+0.40 ng/m3
    Cr: 1.9+1.7 ng/m
    Fe: 283+167 ng/m3
    Ni: 4.8+6.5 ng/m3
    Pb: 30.6+19.0 ng/m3
    Pt: 5.0+8.6 pg/nr
    V: 1.8+1. 4 ng/m3
    Zn: 45.8+33.1 ng/m3
    
    Monitoring Stations: 2 fixed sites:
    (Villa Ada and Istituto superior di Sanita)
    Copollutant (correlation):
    N02r = 0.43
    03r = -0.51
    CO r = 0.67
    S02r = 0.34
    PM10.25r = 0.34
    PMi0r = 0.93
    
    
    PM Increment: 1 pg/m3
    They observed negative association
    between ambient PM25 and respiratory
    function (FVC and FEV,) in the COPD
    panel. The effect on FVC was seen at
    lag 24 h, 48 h, and 72 h. The effect on
    FEVi was evident at lag 72 h. There
    was no statistically significant effect of
    PM2 5 on FVC and FEV, in the
    asthmatic and IHD panels.
    P Coefficient (SE)
    COPD
    FVC(%)
    24 h -0.80 (0.36)
    48-h -0.89 (0.41)
    72-h -1.10 (0.55)
    FEV,(%)
    24 h -0.47 (0.33)
    48-h -0.69 (0.37)
    72-h -1.06 (0.50)
    Asthma
    FVC(%)
    24 h -0.1 4 (0.29)
    48-h -0.07 (0.33)
    72-h -0.06 (0.39)
    FEV,(%)
    24 h -0.30 (0.34)
    48-h -0.36 (0.39)
    72-h -0.40 (0.46)
    December 2009
                                    E-200
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Lee et al. (2007, 0930421
    Period of Study: 2000-2001
    Location: South-Western Seoul
    Metropolitan area, Seoul, South Korea
    Outcome: PEFR (peak expiratory flow
    rate), lower respiratory symptoms (cold,
    cough, wheeze)
    Age Groups: 61-89 yr of age (77.8
    mean age)
    Study Design: longitudinal panel
    survey
    N: 61 adults
    Statistical Analyses: SAS MIXED,
    logistic regression model
    Covariates: Temperature (Celsius),
    relative humidity, age,
    Dose-response Investigated? No
    Statistical Package: SAS 8.0
    Lags Considered: 0-4 days
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 51.15 (19.94)
    Percentiles:
    25th: 33.00
    SOth(Median): 53.20
    75th: 87.54
    Range (Min, Max):
    17.94, 92.71
    Monitoring Stations: 2
    PM Increment: 10 pg/m
    Effect Estimate [Lower Cl, Upper Cl]
    lag:
    PEFR (peak expiratory flow rate)
    -0.54 (-0.89,-0.19)
    1day
    relative odds of a lower respiratory
    symptom (cold, cough, wheeze)
    0.976(0.849,1.121)
    1day
    Reference: Lewis et al. (2005, 0810791
    Period of Study: Wnter 2001-Spring
    2002
    Location: Detroit, Michigan, USA
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Poorer lung function
    (increased diurnal variability and
    decreased forced expiratory volume)
    Age Groups: 7-11 yrold
    Study Design: Longitudinal cohort
    study
    N: 86 children
    
    Statistical Analyses: Descriptive
    statistics and bivariate analyses of
    exposures, multivariable regression
    multivariate analog of linear regression.
    Covariates: Sex, home location,
    annual family income, presence of one
    or more smokers in household, race,
    season (entered as dummy variables),
    and parameters to account for
    intervention group effect.
    Season: Wnter 2001 (Feb 10-23),
    Spring 2001 (May 5-1 8), Summer 2001
    (Jul 14-27), Fall 2001 (Sep22-0ct 5),
    Wnter 2002 (Jan 18-31), and Spring
    2002 (May 18-31)].
    
    Dose-response Investigated? No
    Lags Considered: 1-2 days, 3-5 days
    
    Pollutant: PM25
    Averaging Time: 2 wk
    Mean (SD):
    Eastside
    15.7(10.6)
    
    Southwest
    17.5(12.2)
    Range (Min, Max): 1.0, 56.1
    Monitoring Stations: 2
    Copollutant (correlation):
    
    PM100.93
    03 Daily mean 0.57
    03 8-h peak 0.53
    PM Increment: 12.5 pg/m3
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Lung function among children reporting
    use of maintenance CSs
    Diurnal variability FEV1
    Lag 1:1. 61 -0.5,3.72]
    Lag 1:0.99 -5.64, 7.62] PM2
    
    
    
    5 + 03
    Lag 2: 2.96 -1.74,7.66]
    Lag 2: 4.62 -4.31, 13.54] PM25 + 03
    Lag 3-5: 1.37 [-1.49,4.22]
    Lag 3-5: 2.70 [1.0, 4.40] PM2
    Lowest daily value FEV1
    Lag 1: -2.23 [-6.99,2.53]
    5 + 03
    
    Lag 1:3.36 [-3.92, 10.63] PM2 5 + 03
    Lag 2: -0.21 [-4.09,3.68]
    
    Lag 2: 0.88 [-8.69, 10.46] PM25 + 03
    Lag 3-5: -0.76 [-5.00, 3.49]
    Lag 3-5: -2.78 [-4.87 to -0.70] PM25 +
    03
    
    Lung function among children reporting
    presence of URI on day of lung function
    
    
    
    assessment
    Diurnal variability FEV-
    I an 1 • 4 OR -1 7R Q Q41
    
    
    
    Lag 1:3^99 -276| 10J4] PM25 + 03
    
    
    Lag 2: 7.62 -0.49, 15.73]
    Lag 2: 4. 10 -1.41, 9.60] PM2
    Lag 3-5: 1.47 [-7.73, 10.67]
    5 + 03
    
    Lag 3-5: 3.81 [-1.83, 9.45] PM25 + 03
    
    
    
    
    
    
    Lowest daily value FEV1
    Lag 1: -1.21 5.62,3.21]
    
    
    Lag 1: -0.74 -4.14, 2.65] PM25 + 03
    
    
    
    Lag 2: -0.10 4.36,4.16]
    
    Lag 2: -1.67 -5.09, 1.75] PM25 + 03
    
    
    
    
    
    
    
    
    
    Lag 3-5: -2.88 -5.46 to -0.30
    Lag 3-5: -2.78 -4.79 to -0.77
    03
    
    PM2.5 +
    
    December 2009
                                   E-201
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Liu et al. (2009,1920031
    
    Period of Study: 4 wk in 2005
    
    Location: Windsor, Ontario, Canada
    Outcome: Decreased lung function
    
    Study Design: Panel
    
    Statistical Analysis: mixed-effects
    regression models
    
    Statistical Package: S-PLUS
    
    Age Groups: Asthmatic children,
    9-14 yr
    Pollutant: PM25
    
    Averaging Time: 1, 2 & 3 days
    
    Mean (SD) Unit (1d): 6.5 pg/m3
    
    Range (Min, Max): 2.0-19.0
    
    Copollutant (correlation):
    
    S02: 0.56
    
    N02: 0.71
    
    03: -0.41
    Increment: 5.4 pg/m
    
    Percent Change (Min Cl, Max Cl)
    Lag
    FEV,
    Same Day:-0.5 (-1.3-0.3)
    Lag 1  Day:-0.5 (-1.1-0.5)
    2-Day Avg:-0.6 (-1.5-0.4)
    3-Day Avg:-1.1 (-3.1-0.9)
    FEF25%-75%
    SameDay:-1.9(-3.5--0.3)
    Lag1  Day:-1.2 (-2.8-0.3)
    2-Day Avg:-2.0 (-3.8--0.2)
    3-Day Avg: -3.3 (-7.2-0.8)
    FeNO
    Same Day: 5.3 (-3.6-15)
    Lag1  Day: 1.7 (-6.3-15)
    2-Day Avg: 4.3 (-5.4-15.1)
    3-Day Avg:-17.3 (-33.5-2.9)
    TEARS
    Same Day: 16.9 (2.2-33.6)
    Lag 1  Day: 14.6 (0.8-30.4)
    2-Day Avg: 22.0 (4.8-42.1)
    3-Day Avg: 69.1 (20.1-138.2)
    8-lsoprostane
    Same Day: 5.1 (-3.6-14.5)
    Lag1  Day:-3.8 (-12.1-5.3)
    2-Day Avg: 0.1 (-9.8-11.1)
    3-Day Avg: 5.8 (-15.8-33.0)/
    December 2009
                                    E-202
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Mar et al. (2004, 0573091
    
    Period of Study:  1997-1999
    
    Location: Spokane, Washington
    Outcome: Respiratory Symptoms
    
    Age Groups: Adults: Ages 20-51 yr
    
    Children: Ages 7-12 yr
    
    N: 25 people
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Temperature, relative
    humidity, day of-the-wk
    
    Statistical Package: STATA 6
    
    Lags Considered: 0-2 days
    Pollutant: PM25
    
    Mean (SD):
    
    1997:11.0(5.9)
    
    1998:10.3(5.4)
    
    1999:8.1(3.8)
    
    Unit (i.e. pg/m3):
    
    Monitoring Stations: 1 station
    
    Copollutant (correlation):
    
    PM25
    
    PM,r = 0.92
    
    PM10r = 0.61
    PM Increment: 10 pg/m
    
    OR Estimate [Lower Cl, Upper Cl]
    lag:
    Adult Respiratory symptoms:
    Wheeze:
    1.04[0.86, 1.26] lag 0
    1.00(0.83,1.19] lag 1
    0.99(0.84, 1.17] lag 2
    Breath:
    0.97[0.87, 1.08] lag 0
    0.980.87, 1.10] lag 1
    0.950.80, 1.13] lag 2
    Cough:
    0.86[0.62, 1.21] lag 0
    0.87[0.63, 1.20] lag 1
    0.89[0.66, 1.20] lag 2
    Sputum:
    0.94[0.63, 1.41] lag 0
    0.90(0.62, 1.31]lag1
    0.92(0.66, 1.27] lag 2
    Runny Nose:
    0.98[0.83, 1.15] lag 0
    0.950.82, 1.10] lag 1
    0.930.80, 1.08] lag 2
    Eye Irritation:
                                                                                                               0.91
                                                                                                                   0.70,1.20] lag 0
                                                                                                               0.890.70, 1.13] lag 1
                                                                                                               0.86(0.68, 1.08] lag 2
                                                                                                               Lower Symptoms:
                                                                                                               0.91[0.73, 1.13] lag 0
                                                                                                               0.89(0.72, 1.10] lag 1
                                                                                                               0.89(0.72, 1.10] lag 2
                                                                                                               Any Symptoms:
                                                                                                               0.92[0.80, 1.07] lag 0
                                                                                                               0.890.76, 1.04] lag 1
                                                                                                               0.890.75,1.05]
                                                                                                               lag 2
                                                                                                               Children Respiratory symptoms:
                                                                                                               Wheeze:
                                                                                                               0.55[0.26, 1.19] lag 0
                                                                                                               0.530.18, 1.58] lag 1
                                                                                                               0.550.19, 1.64] lag 2
                                                                                                               Breath:
                                                                                                               1.130.86, 1.48] lag 0
                                                                                                               1.120.86, 1.44] lag 1
                                                                                                               1.10(0.82, 1.48] lag 2
                                                                                                               Cough:
                                                                                                               1.17[0.98, 1.40] lag 0
                                                                                                               1.21(1.00,1.47] lag 1
                                                                                                               1.18(0.99, 1.42] lag 2
                                                                                                               Sputum:
                                                                                                               1.06[0.92, 1.22] lag 0
                                                                                                               1.100.91,1.34] lag 1
                                                                                                               1.090.92, 1.30] lag 2
                                                                                                               Runny Nose:
                                                                                                               1.09[0.85, 1.39] lag 0
                                                                                                               1.12(0.89,1.41]lag1
                                                                                                               1.16(0.94, 1.42] lag 2
                                                                                                               Eye Irritation:
                                                                                                               0.93(0.53,1.64] lag 0
                                                                                                               0.75(0.45, 1.27] lag 1
                                                                                                               0.77(0.65, 0.91] lag 2
                                                                                                               Lower Symptoms:
                                                                                                               1.18(1.00,1.38] lag 0
    1.21
    1.17
    Any
    1.17
    1.22
    1.23
    1.00, 1.46
    0.96, 1.43
    Symptom
    1.03, 1.34
    1.04, 1.43
    1.07, 1.42
    Iag1
    lag 2
    s:
    lagO
    Iag1
    lag 2
    December 2009
                                    E-203
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Mar et al. (2005, 0875661
    Period of Study: 1999-2001
    Location: Seattle, Washington
    Outcome: Pulmonary function (arterial   Pollutant: PM2 5
    oxygen saturation) and cardiac function
    (heart rate and blood pressure)         Averaging Time: 24-h avg
    Study Design: Time series
    Statistical Analyses: Linear logistic
    regression
    Age Groups: > 57
                                        Increment: 10|jg/m
                                        % Increase (Lower Cl, Upper Cl)
                                        Lag
                                        Personal:
                                        Systolic: 0.37 (-0.93, 1.67)0
                                        Diastolic: -0.20 (-0.85, 0.46) 0
                                        Indoor:
                                        Systolic: 0.92 (-2.04, 3.87) 0
                                        Diastolic: 0.38 (-1.43, 2.20)0
                                        Outdoor:
                                        Systolic: -0.81 (-2.34, 0.73) 0
                                        Diastolic:-0.46 (-1.49, 0.57)
                                        0
                                        % Increase between heart rate and
                                        PM2 5 exposure for people > 57
                                        PM25:
                                        Personal: 0.44 (0.04, 0.84) 0
                                        Indoor: 0.22 (-0.71,1.16)0
                                        Outdoor:-0.75 (-1.42 to-0.07)0
    Reference: Mar et al. (2005, 0887591
    Period of Study: 1999-2002
    Location: Seattle, Washington
    Outcome: Respiratory Symptoms
    Age Groups: 6-13 yr
    Study Design: Time-Series
    N: 19 children
    Statistical Analyses: Polynomial
    distributed lag model, Poisson
    regression
    Covariates: Age, ambient NO levels,
    temperature, relative humidity,
    modification of use of inhaled
    corticosteroids
    Season: Winter, Spring
    Dose-response Investigated? No
    Statistical Package: STATA
    Lags Considered: 0-8 h
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD):
    Results presented in Fig 1.
    Monitoring Stations: 3 Stations
    PM Increment: 10 pg/m
    Change in FE(NO) (exhaled NO
    concentration) with air pollution
    [Lower Cl, Upper Cl] lag:
    Medication use:
    No meds: 6.99[3.43,10.55] lag 1-h
    Meds:-0.18[-3.33, 2.97] lag 1-h
    No meds: 6.30[2.64,  9.97] lag 4-h
    Meds: -0.77[-4.58, 3.04] lag 4-h
    No meds: 0.46[-1.18,2.11] lag 8-h
    Meds: 0.40[-1.94, 2.74] lag 8-h
    Reference: McCreanor et al. (2007,
    0928411
    Period of Study: 2003-2005
    Location: London, England
    Outcome: Decreased Lung Function
    Age Groups: Adults
    Study Design: Crossover study
    N: 60 adults
    Statistical Analyses: Linear regression
    Covariates: Temperature, relative
    humidity, age,  sex, bod-mass index,
    and race or ethnic group
    Pollutant: PM25
    Averaging Time: 1  h
    Mean (SD): NR
     SOth(Median): Oxford St: 28.3
    Hyde Park: 11.9
    Range (Min, Max):
    Oxford St: (13.9, 76.1)
    Hyde Park: (3, 55.9)
    % changes in FEV and FVC are
    presented  in  Fig 1-3. Results are not
    presented  quantitatively in text or
    tables. The authors did not find  any
    significant  differences in respiratory
    symptoms between the two locations.
    Also, there were no significant
    differences in sputum eosinophil counts
    or eosinophil cationic protein levels.
    Reference: Moshammer and
    Neuberger (2003, 0419561
    Period of Study: 2000-2001
    Location: Linz, Austria
    Outcome: Lung Function: FVC, FEVi,
    MEF25, MEF50, MEF75, PEF,  LQ Signal,
    PAS Signal
    Age Groups: Ages 7-10
    Study Design: Case-crossover
    N: 161  children
    1898-2120 "half-h means"
    Statistical Analyses: Correlations
    Regression Analysis
    Covariates: Morning, evening, night
    Season: Spring, Summer, Winter, Fall
    Dose-response Investigated? No
    Pollutant: PM25
    Averaging Time: 8 h means & daily
    means
    Mean (SD): 14.61 (10.83)
    Range (Min, Max):
    (NR, 119.92)
    Monitoring Stations: 1
    Copollutant (correlation):
    LQ = 0.751
    PAS = 0.354
    Notes: "Acute effects of 'active particle
    surface' as measured by diffusion
    charging were found on pulmonary
    function (FVC, FEVi,MEF50) of
    elementary school children and on
    asthma-like symptoms of children who
    had been classified  as sensitive."
    December 2009
                                    E-204
    

    -------
    Study
    Reference: Moshammer et al. (2006,
    0907711
    Period of Study: 2000-2001
    Location: Linz, Austria
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Murata et al. (2007,
    A nr\A rr\\
    Design & Methods
    Outcome: Respiratory symptoms and
    decreased lung function
    Age Groups: Children ages 7-10
    Study Design: Time-series
    N: 163 children
    
    Statistical Analyses: Generalized
    estimating equations model
    Covariates: Sex, age, height, weight
    Dose-response Investigated? NR
    Statistical Package: NR
    
    Lags Considered: 1
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Exhaled nitric oxide levels,
    Concentrations1
    Pollutant: PM25
    Averaging Time: 8 h
    Mean (SD):
    Maximum 24 h: 76.39
    
    Annual avg: 19.06
    Percentiles: 8-h mean 25th: 8.64
    8-h mean SOth(Median): 15.70
    8-h mean 75th: 25.82
    Monitoring Stations: 1 station
    
    Copollutant (correlation):
    PM, r = 0.95
    PMio r= 0.93
    
    N02r = 0.54
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM25
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    % change in Lung Function per 10
    ug/m3
    PP\/. n 0*3
    rtv. U.ZO
    FVC: 0.08
    FEV05:0.33
    MEF75%: -0.49
    MEF50%: -0.58
    MEF25%: -0.83
    PEF: 0.41
    % change in Lung Function per IQR
    FEV: -0.59
    FVC: -0.2
    FEV0.5: 0.85
    MEFy5%' -1 25
    MEF50%:-148
    MEF25%:-2.14
    PEF: -1.06
    Multiple pollutant model
    FEV: 0.10
    FVC: 0.21
    FEV05:0.06
    MEF75%:-0.15
    MEF50%: 0.04
    MEF25%: -0.21
    PEF: -0.1 8
    % change in Lung Function per IQR
    FEV: 0.27
    FVC: 0.54
    FEV05:0.15
    MEF75%: -0.39
    MEF50%:0.11
    MEF25%: 0.54
    PEF: 0.015: -0.47
    PM Increment: IQR 110 pg/m3
    Period of Study: Nov 2004
    Location: Tokyo, Japan
    (eNO), a marker of airway inflammation
    Age Groups: 5-1 Oyr
    Study Design: Cohort/Panel study
    N: 19 schoolchildren*
    Statistical Analyses:  Linear regression
    Covariates: None
    Season: Nov (fall)
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: Lag h 1-24, 8-h ma,
    7-h ma, 6-h ma, 24-h ma
    Averaging Time: Hourly, 24 h
    Mean (SD):
    39.0 (16.9) pg/m3 (daily mean)
    Range (Min, Max):
    10,120 (range of hourly values)
    Monitoring Stations: 1, on the street
    where the children lived
    Mean [Lower Cl, Upper Cl] lag:
    0.145 [0.62, 0.228] ppb eNO
    8-h ma
    Notes: Associations for lag h 1-24
    presented in figures. Authors state
    "Individual hourly lag models showed a
    consistent association between the
    eNO value and PM2 5 for exposure in
    the previous 24 h"
    "The trend on the graphs strongly
    suggest that fluctuations in eNO were
    affected by changes in air pollutants
    over at least the previous 8-h period"
    PM25, black carbon, and NOX were all
    highly correlated (shown in figures), so
    effects are difficult to separate
    Pollutant concentrations peaked in the
    morning and evening h during traffic
    peaks
    December 2009
                                    E-205
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Neuberger et al. (2004,
    0932491
    
    Period of Study: Jun 1999-Jun 2000
    
    Location: Austria (Vienna and a rural
    area near Linz)
    Outcome: Questionnaire derived
    asthma score, and a 1-5 point
    respiratory health rating by parent
    
    Age Groups: 7-1 Oyr
    
    Study Design: Cross-sectional survey
    
    N: about 2000 children
    
    Statistical Analyses:  mixed models
    linear regression-used factor analysis to
    develop the "asthma score"
    
    Covariates: Pre-existing respiratory
    conditions, temperature,  rainy days, #
    smokers in household, heavy traffic on
    residential street, gas stove or heating,
    molds, sex, age of child,  allergies of
    child, asthma in other family members
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 4-wk avg (preceding
    interview)
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Copollutant (correlation):
    
    PMio(r=0.94) in Vienna
    PM Increment: 10 pg/m
    
    Change in mean associated unit
    increase in PM
    
    (p-value)
                                                                                                                Respiratory Health score
                                                                                                                Vienna: 0.016 (p>0.05)
                                                                                                                lag 4 week avg
                                                                                                                Rural area: 0.022 (p < 0.05)
                                                                                                                lag 4 week avg
                                                                                                                Asthma score
                                                                                                                Vienna: 0.006 (p>0.05)
                                                                                                                lag 4 week avg
                                                                                                                Rural area: 0.004 (p>0.05)
                                                                                                                lag 4 week avg
    Reference: Neuberger et al. (2004,
    0932491
    Period of Study: Sep 1999-Mar 2000
    
    Location: Vienna, Austria
    Outcome: Ratio measure: Time to peak
    tidal expiratory flow divided by total
    expiration time (i.e., tidal lung function,
    a surrogate for bronchial obstruction)
    
    Age Groups: 3.0-5.9 yr (preschool
    children)
    
    Study Design:
    Longitudinal prospective cohort
    
    N: 56 children
    
    Statistical Analyses: mixed models
    linear regression, with autoregressive
    correlation structure
    
    Covariates: Age, sex, respiratory rate,
    phase angle, temperature,
    kindergarten, parental education,
    observer (also in sensitivity analyses:
    height, weight, cold/sneeze on same
    day, heating with fossil fuels, hair
    cotinine, number of tidal slopes used to
    measure tidal lung function)
    
    Dose-response Investigated? No
    
    Statistical Package: SAS 8.0
    
    Lags Considered: Lag 0
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    PM Component: Total carbon
    
    EC
    
    OC
    
    Copollutant (correlation):
    
    PM10(r=0.94) in Vienna
    PM Increment: Interquartile range (NR)
    
    Change in mean associated with an
    IQR increase in PM (p-value)
                                                                                                                PM2.5 mass: -0.987 (0.091)
    
                                                                                                                lagO
    
                                                                                                                Total carbon:-0.815 (0.041)
    
                                                                                                                lagO
    
                                                                                                                EC:-0.657 (0.126)
    
                                                                                                                lagO
    
                                                                                                                OC:  -0.942 (0.025)
    
                                                                                                                lagO
    Reference: Neuberger et al. (2004,
    0932491
    
    Period of Study: Oct. 2000-May 2001
    
    Location: Linz, Austria
    Outcome: Forced oscillatory resistance
    (at zero Hz), FVC, FEV,, MEF25, MEF50,
    MEF75, PEF
    
    Age Groups: 7-1 Oyr
    
    Study Design: Longitudinal
    prospective cohort
    
    N: 164 children
    
    Statistical Analyses: Mixed  models
    linear regression with autoregressive
    correlation structure
    
    Covariates: Sex, time and individual
    
    Season: Oct-May
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: Lag 0-7
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Monitoring Stations: 1
    PM Increment: 1 pg/m
    
    Notes: Authors report increased
    oscillatory resistance significantly
    associated with PM25 (lag 0)
    December 2009
                                     E-206
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: O'Connor et al. (2008,
    1568181
    Period of Study: Aug 1998-Jul 2001
    Location: Boston, the Bronx, Chicago,
    Dallas, New York, Seattle, Tucson
    Outcome: Pulmonary function and
    respiratory symptoms
    Age Groups: 5-12 yr
    Study Design: Inner-City Asthma Study
    (ICAS)-Panel/cohort study
    N: 861 children
    Statistical Analyses: Mixed effects
    models
    Lags Considered: Lag 0-6, 0-4
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 14
    Range (Min, Max):
    5-35 (estimated from Fig)
    Copollutant (correlation):
    N02 (F0.59)
    S02 (F0.37)
    CO (F0.44)
    03 (F-0.02)
    PM Increment: 13.2 pg/rri  90th-10th
    percentile
    Change in pulmonary function
    FEV,: -1.47 (-2.00 to -0.94) lag 0-4
    PEFR:-1.10 (-1.65 to-0.56) lag 0-4
    PM25+03+N02
    FEVi:-0.73(-1.33to-0.12)lagO-4
    PEFR: -0.25 (-0.88, 0.38) lag 0-4
    
    Risk of Respiratory Symptoms
    lag
    Wheeze: 0.98 (0.88,1.09) lag 0-4
    Nighttime asthma: 1.11 (0.94,1.30)
    lag 0-4
    Slow play: 1.01  (0.89,1.15) lag 0-4
    Missed school:  1.33 (1.06,1.66) lag 0-4
    PM25+03+N02
    Wheeze: 0.92 (0.81,1.05) lag 0-4
    Nighttime asthma: 1.03 (0.86,1.23)
    lag 0-4
    Slow play: 0.92 (0.79,1.06) lag 0-4
    Missed school:  1.13 (0.87,1.45) lag 0-4
    Reference: Peacock et al. (2003,
    0420261
    Period of Study: Nov 1996-Feb 1997
    Location: northern Kent, UK
    Outcome: Reduced peak expiratory
    flow rate (PEFR)
    Age Groups: 7-13 yr of age
    Study Design: Time Series
    N:179
    Statistical Analyses: generalized
    estimating equations
    Covariates: Day of the week, 24-h
    mean outside temperature.
    Season: Wnter
    Dose-response Investigated? No
    Statistical Package: STATA
    Lags Considered: Same day, lag 1,
    lag 2, 5-day ma
    Pollutant: Sulfate (SOi)
    Averaging Time: Daily avg
    Mean (SD): Urban 2
    24 h avg: 1.3 (1.1)
    Percentiles:
    10th: Urban 2 0.5
    90th: Urban 2 2.4
    Range (Min, Max):
    Urban 2  0.3, 6.7
    Monitoring Stations: 3
    Sulfate (S042~)
    Increment: 1.3 pg/m3
    Odds ratio [Lower Cl, Upper Cl]
    lag:
    1.090 [0.898, 1.322]
    5 days
    Reference: Peled, et al. (2005,
    1560151
    Period of Study: 5-6 wk between
    Mar-Jun 1999 and Sep-Dec 1999.
    Location: Ashdod, Ashkelon and
    Sderot, Israel
    Outcome: Reduced peak expiratory
    flow (PEF)
    Age Groups: 7-1 Oyr
    Study Design: Nested cohort study
    N:285
    Statistical Analyses: Time series
    analysis
    Generalized linear model, generalized
    estimating equations, one-way ANOVA,
    generalized linear model
    Covariates: Seasonal changes,
    meteorological conditions and personal
    physiological, clinical and
    socioeconomic measurements
    Season: Spring, Fall
    Dose-response Investigated? No
    Statistical Package: STATA
    Pollutant: PM25
    Averaging Time: Daily
    Mean:
    Ashkelon: 24.0
    Sderot: 29.2
    Ashdod: 23.9
    PM Component: Local industrial
    emissions, desert dust, vehicle
    emissions and emissions from two
    electric power plants
    Monitoring Stations: 6
    Copollutant: PM,0
    PM Increment: 1 pg/m
    P coefficient (SE) [95% Cl]
    Ashkelon:
    PM25 MAX:-0.144 (0.12) [-0.38-0.09]
    Ashdod:
    PM25 MAX:-2.74 (0.61) [-3.95-1.53]
    PM25 MAX TMAX: 0.11 (0.02) [0.06-
    0.16]
    In Ashdod, PM25 and an interaction
    between PM2 5 and temperature were
    significantly associated.
    December 2009
                                    E-207
    

    -------
                  Study
           Design & Methods
             Concentrations1
       Effect Estimates (95%  Cl)
    Reference: Penttinen et al. (2006,
    0879881
    
    Period of Study: Nov 1996-Apr 1997
    
    Location: Helsinki, Finland
    Outcome: Decreased lung function and  Pollutant: PM25
    respiratory symptoms
                                         PM Component: Soil, heavy fuel oil,
    Age Groups: Adults, mean age 53 yr    sea salt
    Study Design: Time Series
    
    N: 78 people
    
    Statistical Analyses: Generalized least
    squares autoregressive model
    
    Covariates: Temperature, relative
    humidity, day of study, day of study
    squared, binary dummy variable for
    weekends
    
    Season: Winter, Spring
    
    Dose-response Investigated? NR
    
    Statistical Package: SAS version 6
    
    Lags Considered: 0-3
    Averaging Time: 24 h
    Percentiles: 26th:
    Long range transport: 2.44
    Local combustion: 1.75
    Soil: 0.14
    Heavy fuel oil:-0.13
    Sea Salt: 0.22
    Unidentifiable:-1.41
    All sources: 6.47
    60th(Median):
    Long range transport: 4.15
    Local combustion: 2.41
    Soil: 0.64
    Heavy fuel oil: 0.10
    Sea Salt: 0.27
    Unidentifiable: 0.02
    All sources: 8.37
    76th:
    Long range transport: 7.33
    Local combustion: 3.05
    Soil: 1.46
    Heavy fuel oil: 0.52
    Sea Salt: 0.42
    Unidentifiable: 0.74
    All sources: 11.15
    Range (Min, Max):
    Long range transport: (-0.89, 28.31)
    Local combustion: (0.83, 6.51)
    Soil: (-1.13, 6.43)
    Heavy fuel oil: (-0.67,  4.74)
    Sea Salt: (0.09, 0.98)
    Unidentifiable: (-4.40,  4.77)
    All sources: (4.11, 33.53)
    
    Monitoring Stations: 1 site
    PM Increment: 1.3|jg/m
    
    PMu, long range:
    PEF Morning:
    0.37[-0.59, 1.34] lag 0
    -1.04[-1.88 to-0.19] lag 1
    -0.82[-1.81,0.16] lag 2
    0.22[-0.64,1.08] lag 3
    -0.24[-1.12,0.64] 5 day mean.
    
    PEF Afternoon:
    0.20[-0.67, 1.06] lag 0
    -0.20[-1.24, 0.83] lag 1
    -0.30[-1.14,0.53] lag 2
                                                                                                                 0.45
                                                                                                                 0.03
        -0.57, 1.47] lag 3
        -0.79, 0.85] 5 day mean.
                                                                                                                 PEF Evening:
                                                                                                                  -0.33[-1.30, 0.64] lag 0
                                                                                                                 -0.29[-1.13, 0.55] lag 1
                                                                                                                 -0.41-1.46, 0.64 lag 2
                                                                                                                 0.39[-0.47,1.24] lag 3
                                                                                                                 0.07[-0.81,0.95]5daymean
    
                                                                                                                 PMu, local combustion:
                                                                                                                 PEF Morning:
                                                                                                                 -0.73[-1.69, 0.23
                                                                                                                 -0.461-1.24, 0.32
                                                                                             lagO
                                                                                             Iag1
                                                                                                                 -0.43[-1.49, 0.63] lag 2
                                                                                                                 0.34[-0.47, 1.15] lag 3
                                                                                                                 -0.25[-1.03,0.53] 5 day mean.
    
                                                                                                                 PEF Afternoon:
                                                                                                                  -0.21 [-1.07, 0.65] lag 0
                                                                                                                 -0.81[-1.77, 0.16] lag 1
                                                                                                                 -0.83[-1.74, 0.09] lag 2
                                                                                                                 0.20[-0.80,1.20] lag 3
                                                                                                                 -0.87[-1.63 to -0.12] 5 day mean.
    
                                                                                                                 PEF Evening:
                                                                                                                  -0.51[-1.48, 0.45] lag 0
                                                                                                                 -1.16[-1.93 to-0.39 lag 1
                                                                                                                 0.23[-1.35, 0.90] lag 2
                                                                                                                 0.56[-0.21,1.32] lag 3
                                                                                                                 -1.14[-1.95 to-0.33]5day mean
    
                                                                                                                 PMis, soil:
                                                                                                                 PEF Morning:
                                                                                                                 0.81(0.05,1.57] lag 0
                                                                                                                 0.03 [-0.65, 0.71] lag 1
                                                                                                                 0.50[-0.34, 1.35] lag 2
                                                                                                                 -0.07[-0.74, 0.61] lag 3
                                                                                                                 0.39[-0.46,1.23] 5 day mean.
    
                                                                                                                 PEF Afternoon:
                                                                                                                 1.05[0.38, 1.72] lag 0
                                                                                                                 0.40-0.38, 1.19] lag 1
                                                                                                                 0.66 [0.03, 1.30] lag 2
                                                                                                                 -0.36[-1.12,0.41] lag 3
                                                                                                                 0.55 [-0.21,1.32] 5 day mean.
    
                                                                                                                 PEF Evening:
                                                                                                                 1.080.33, 1.84] lag 0
                                                                                                                 1.000.31,1.68] lag 1
                                                                                                                 0.33[-0.56,1.22] lag 2
                                                                                                                 -0.84 [-1.53 to-0.15]lag3
                                                                                                                 0.90[0.08,1.73] 5 day mean
    
                                                                                                                 PM2.s,oil:
                                                                                                                 PEF Morning:
                                                                                                                 -0.22[-1.00,0.56] lag 0
                                                                                                                 -0.20[-1.24, 0.84] lag 1
                                                                                                                 0.66[-0.68, 2.00] lag 2
                                                                                                                 0.57 [-0.18, 1.32] lag 3
                                                                                                                 0.10[-0.61,0.81]5daymean.
    
                                                                                                                 PEF Afternoon:
                                                                                                                 -0.04[-0.75, 0.67] lag 0	
    December 2009
                                     E-208
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                                 0.29[-0.98, 1.55] lag 1
                                                                                                                 0.08 [-1.13, 1.28] lag 2
                                                                                                                 0.62[-0.31,1.54] lag 3
                                                                                                                 0.07 [-0.64, 0.78] 5 day mean.
    
                                                                                                                 PEF Evening:
                                                                                                                 0.57[-0.23, 1.37] lag 0
                                                                                                                 0.12-0.92,1.15 lag 1
                                                                                                                 -0.97[-2.39, 0.45] lag 2
                                                                                                                 0.40[-0.31,1.12] lag 3
                                                                                                                 0.43[-0.33,1.19] 5 day mean
    
                                                                                                                 PM2.s, salt:
                                                                                                                 PEF Morning:
                                                                                                                 0.76[-0.13, 1.65] lag 0
                                                                                                                 0.43 [-0.30, 1.16] lag 1
                                                                                                                 0.13
                                                                                                                 0.38
                                                                          -0.75,1.02] lag 2
                                                                          -0.47, 1.23] lag 3
                                                                     0.95[-0.18, 2.09] 5 day mean.
    
                                                                     PEF Afternoon:
                                                                     0.62-0.18,1.41 lagO
                                                                     0.80-0.08, 1.69 Iag1
                                                                     0.14-0.62,0.90 lag 2
                                                                     0.16-0.83,1.15 Iag3
                                                                     0.88 [-0.18,1.94] 5 day mean.
    
                                                                     PEF Evening:
                                                                     1.090.19, 1.98] lag 0
                                                                     0.63-0.10, 1.35] lag 1
                                                                     0.32[-0.62,1.26] lag 2
                                                                     -0.31[-1.16,0.54] lag 3
                                                                     0.88[-0.27, 2.02] 5 day mean
    
                                                                     PMu, unidentified:
                                                                     PEF Morning:
                                                                     0.38[-0.67,1.43] lag 0
                                                                     0.09  " "          '
                                                                     0.22
                                                                     0.78 [-0.10, 1.66] lag 3
                                                                     0.78[-0.14,1.69] 5 day mean.
                                                                                                                     -0.83,1.00] lag 1
                                                                                                                     -0.82, 1.26] lag 2
                                                                                                                 PEF Afternoon:
                                                                                                                 0.02
                                                                                                                 0.65
                                                                                                                 0.17
                                                                                                                 0.69
                                                                          -0.92, 0.96
                                                                          -0.48, 1.77
                                                                          -0.71, 1.05
                                                                          -0.36, 1.75
                                               lagO
                                               Iag1
                                               lag 2
                                               Iag3
                                                                                                                 0.17 [-0.72,1.06] 5 day mean.
    
                                                                                                                 PEF Evening:
                                                                                                                 -0.11[-1.17, 0.95] lag 0
                                                                                                                 0.19[-0.72,1.10] lag 1
                                                                                                                     -0.25, 1.96] lag 2
                                                                                                                     -0.70,1.01] lag 3
                                                                     0.86
                                                                     0.15
                                                                     -0.19[-1.15, 0.77] 5'day mean
    
                                                                     PMu, local combustion:
                                                                     PEF morning:
                                                                     Cu:-0.25 [-1.25, 0.75]
                                                                     Zn:-0.45[-1.19,0.29]
                                                                     Mn: 0.13[-0.83, 1.08]
                                                                     Fe: 0.08[-0.70, 0.85],
                                                                     PEF afternoon:
                                                                     Cu:-0.37[-1.29, 0.55]
                                                                     Zn:-0.19[-0.87, 0.50]
                                                                     Mn:-0.48[-1.37,0.42]
                                                                     Fe: 0.29[-0.45, 1.04],
                                                                     PEF evening:
                                                                     Cu:-0.48[-1.47, 0.52]
                                                                     Zn:-0.17[-0.92, 0.57]
                                                                     Mn: 0.51[-0.44, 1.47]
                                                                     Fe: 0.34[-0.46, 1.14]
    
                                                                     PMu, long range:
                                                                     PEF morning:
                                                                     S: 0.11 [-0.886, 1.07]
                                                                     K:-0.10[-1.00, 0.80]
                                                                     Pb:-0.62[-1.37, 0.13]
    December 2009
                             E-209
    

    -------
                  Study                       Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                Br:-0.40 [-1.40, 0.60].
                                                                                                                PEF afternoon:
                                                                                                                S:-0.05[-0.92,0.81]
                                                                                                                K: 0.26[-0.56, 1.07]
                                                                                                                Pb:-0.12[-0.84, 0.60]
                                                                                                                Br: 0.15[-0.81,1.12].
                                                                                                                PEF evening:
                                                                                                                S: 0.08[-0.86, 1.02
                                                                                                                K: 0.18[-0.70,1.07;
                                                                                                                Pb: -0.20[-0.97, 0.58]
                                                                                                                Br: 0.35[-0.71,  1.40]
    
                                                                                                                PMis, soil:
                                                                                                                PEF morning:
                                                                                                                Si: 0.27[-0.43, 0.97]
                                                                                                                Al: 0.17 [-0.72, 1.05]
                                                                                                                Ca:0.13[-1.08, 1.35].
                                                                                                                PEF afternoon:
                                                                                                                Si: 0.39[-0.24,1.01]
                                                                                                                Al: 0.49-0.29, 1.27
                                                                                                                Ca: 0.15[-0.92, 1.22]
                                                                                                                PEF evening:
                                                                                                                Si: 0.60-0.06, 1.26
                                                                                                                Al: 0.76[-0.08,1.60
                                                                                                                Ca: 0.90[-0.22, 2.03]
    
                                                                                                                Plfe, Oil combustion:
                                                                                                                PEF morning:
                                                                                                                 V:-0.01 [-0.87, 0.86]
                                                                                                                Ni:-0.09[-1.08,0.90].
                                                                                                                PEF afternoon:
                                                                                                                V:-0.48[-1.32,0.35
                                                                                                                Ni: 0.26[-0.72,1.23.
                                                                                                                PEF evening:
                                                                                                                V: 0.02[-00.88, 0.92]
                                                                                                                Ni: 0.50[-0.55,1.55]
    
                                                                                                                Plfe, Sea salt:
                                                                                                                PEF morning:
                                                                                                                Na: 0.92[-0.34, 2.17]
                                                                                                                Cl: 0.93[0.08, 1.79]
                                                                                                                PEF afternoon:
                                                                                                                Na: 0.96[-0.24, 2.16]
                                                                                                                Cl: 0.57[-0.22,  1.36]
                                                                                                                PEF evening
                                                                                                                Na: 0.87[-0.40, 2.15]
                 	Cl:0.65[-0.19,  1.49]
    December 2009                                                     E-210
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Pino et al. (2004, 0502201
    
    Period of Study: Apr 1995-Oct 1996
    
    Location: Santiago, Chile
    Outcome: Respiratory Symptoms,
    Wheezing bronchitis
    
    Study Design: Time-series
    
    Statistical Analyses: Bayesian
    hierarchical analysis, cubic spline
    
    Age Groups: 4 mo-2 yr old
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Mean (SD) unit: 52.0 (31.6)
    
    Range (5th, 95th): 17.0,114.0
    
    Copollutants (correlation):
    
    S02: r= 0.73
    
    NO,: F 0.85
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    
    % increase in wheezing bronchitis and
    PM2 5 exposure for infants 4 mo-2 yr old
    4.75(1.25,8.25)1
                                                                                                                3.85
                                                                                                                2.25
                                                                                                                1.75 (-2.20, 5.75)4
         0.45, 7.75) 2
         -1.00,6.00)3
                                                                                                                4.00
                                                                                                                5.00
                                                                                 0.25, 8.00
                                                                                 1.00,8.50
                                                                                                                7.00(3.50,11.00)7
                                                                                                                8.10(4.00, 11.25)8
                                                                                                                9.00
                                                                                                                8.75
                                                                                 6.00, 12.00)9
                                                                                 5.75, 12.00) 10
                                                                                                                1.50 (-3.50, 4.75)11
                                                                                                                0.25
                                                                                                                0.00
                                                                                 -3.75, 4.25) 12
                                                                                                                     -4.00, 4.00) 13
                                                                                                                1.00 (-3.50, 4.50)14
                                                                                                                1.50 (-3.50, 4.50)15
                                                                                                                OR for wheezing bronchitis and PM2 5
                                                                                                                exposure in infants 4 mo to 2 yr old
                                                                                                                according to family history of asthma
                                                                                                                Yes to family history of asthma
                                                                                                                1.09(1.00,1.19)1
                                                                                                                1.10(1.02, 1.20)2
                                                                                                                1.11 (1.02, 1.22)3
    
                                                                                                                No to family history of asthma
                                                                                                                1.04
                                                                                                                1.02
                                                                                 1.00, 1.08
                                                                                 0.98, 1.06
                                                                                                                1.01(0.96,1.05)3
    Reference: Rabinovitch et al., (2006,
    0880311
    Period of Study: 2001-2003 (two
    winters 2001-2002 and 2002-2003)
    
    Location: Denver, CO
    Outcome: Bronchodilator doser
    activations (daily) and urinary
    leukotriene E4 (daily)
    
    Age Groups: Children 6-1 Syr old
    
    Study Design: School-based cohort
    study
    
    N: 73 children
    
    Statistical Analyses: Doser activation:
    Poisson regression with GEE with AR1
    working covariance
    
    Urinary leukotriene E4: linear mixed
    model with spatial exponential
    covariance
    
    Covariates: Temperature, pressure,
    humidity, time trend, Friday indicator,
    upper respiratory infection (URI), height
    (leukotriene E4 only).
    
    Season: Winter
    
    Dose-response Investigated? NR
    
    Statistical Package: SAS
    
    Lags Considered: 0-2 days
    Pollutant: PM25
    Averaging Time:
    Morning (midnight to 11: 00AM) mean
    Morning (midnight to 11: 00AM)
    maximum
    24-h mean
    Mean (SD):
    24-h mean, TEOM
    Year 1,N: 55 days: 6.5 (3.2)
    Year 2, N: 128 days: 8.2 (3.7)
    24-h mean, FRM
    Year 1,N: 55 days: 11.8 (7.2)
    Year 2, N: 122 days: 11.2 (5.5)
    Morning mean, TEOM
    Year 1,N: 71 days: 7.4 (4.7)
    Year 2, N: 127 days: 9.1 (5.0)
    Morning maximum, TEOM
    Year 1,N: 71 days: 15.5 (9.5)
    Year 2, N: 127 days: 18.4 (9.6)
    
    Percentiles:
    24-h mean, TEOM
    Yearl
    25th: 4.4
    SOth(Median): 6.2
    75th: 7.9
    Year 2
    25th: 55
    SOth(Median): 7.3
    75th: 9.9
    24-h mean, FRM
    Yearl
    25th: 7.8
    50th(Median):10.1
    75th: 14.1
    Year 2
    25th: 7.5
    SOth(Median): 9.3
    75th: 13.3
    
    Morning mean, TEOM
    Yearl
    25th: 4.0
    PM Increment: IQR (over current and
    previous day)
    Doser Activation
    Morning avg PM2s TEOM
    Yearl:
    Pet Increase: 3.0 [-0.5: 6.6] p = 0.10
    Year 2:
    Pet Increase: 2.7 [1.1: 4.4] p = 0.006
    Aggregated yr: 2.2 [0.7: 3.6] p = 0.005
    Morning max PM2s TEOM
    Yearl
    Pet Increase: 4.0 [0.5: 7.6] p = 0.02
    Year 2
    Pet Increase: 2.3 [0.7: 4.0] p = 0.009
    Aggregated yr 2.6 [0.9: 4.2] p= 0.002
    24-h PM2S
    TEOM
    Lag 0:0.4 [-0.7:1.6] p-value = 0.45
    Lag 1:0.9 [-0.7: 2.4] p-value = 0.27
    Lag2:-0.4[-1.7:0.9]p-value = 0.59
    Lag 0-2 Avg: 0.6 [-1.0: 2.2]
    p-value = 0.43
    FRM
    Lag 0:0.2 [-1.2:1.6] p-value = 0.81
    Lag 1:0.9 [-0.9: 2.6] p-value = 0.31
    Lag 2:-0.2 [-2.2:1.8] p-value = 0.88
    Lag 0-2 Avg: 1.2 [-0.6: 2.9]
    p-value = 0.20
    Morning avg PMu TEOM
    URI not adjusted
    Mild/Moderate Asthmatics:
    1.5 [-0.5: 3.4] p = 0.14
    Severe Asthmatics: 3.7 [1.6: 5.8]
    p- = 0.0006
    Difference between severity groups,
    p = 0.12
    Aggregated severity group:
    2.2 [0.7: 3.6] p= 0.005
    URI adjusted
    Mild/Moderate Asthmatics:
    1.0 [-1.9: 3.9]p= 0.50
    Severe Asthmatics: 6.0 [1.8:10.1]
    p = 0.006
    Difference between severity groups,
    December 2009
                                     E-211
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                           SOth(Median): 5.9
                                                                           75th: 9.6
                                                                           Year 2 25th: 5.2
                                                                           50th  (Median): 8.5
                                                                           75th: 11.6
    
                                                                           Morning maximum, TEOM
                                                                           Year 125th: 8
                                                                           50th  (Median): 13
                                                                           75th: 20
                                                                           Year 2 25th: 11
                                                                           50th  (Median): 16
                                                                           75th: 23
    
                                                                           Range (Min, Max):
                                                                           24-h  mean, TEOM
                                                                           YeaM
                                                                           Year 2
                                              2.1,23.7
                                              1.7, 20.5
                                                                           24-h mean, FRM
                                                                           Year!
                                                                           Year 2
                                              4.3, 53.5
                                              3.4, 26.3
                                                                           Morning mean, TEOM
                                                                           Year!
                                                                           Year 2
                                              1.4, 22.7
                                              1.6, 30.2
                                                                           Morning maximum, TEOM
                                                                           Year!
                                                                           Year 2
                                              4,42
                                              4,46
                                                                           Monitoring Stations: 2 (1 TEOM and 1
                                                                           Federal Reference Monitor [FRM])
                                        p = 0.08
                                        Aggregated severity groups:
                                        2.7[-0.1:5.4]p=0.06
                                        Morning maximum PIfcTEOM
                                        URI not adjusted
                                        Mild/Moderate Asthmatics:
                                        1.9 [-0.2: 4.1] p= 0.07
                                        Severe Asthmatics: 3.9 [1.1: 6.8]
                                        p = 0.006
                                        Difference between severity groups,
                                        p = 0.29
                                        Aggregated severity groups: 2.6 [0.9:
                                        4.2] p= 0.002
                                        URI adjusted
                                        Mild/Moderate Asthmatics:
                                        1.6 [-2.2: 5.4] p = 0.41
                                        Severe Asthmatics: 8.1 [2.9:13.4]
                                        p = 0.003
                                        Difference between severity groups,
                                        p = 0.03
                                        Aggregated severity groups:
                                        3.8 [0.2: 7.4] p = 0.04
                                        Leukotriene E4
                                        24-h PM2.j
                                        TEOM
                                        Lag 0:3.3 [-0.7: 7.2] p = 0.09
                                        Lag 1: -1.6[-5.7: 2.5] p = 0.40
                                        Lag 2:1.1 [-2.8: 5.1] p= 0.64
                                        Lag 0-2 Avg: 2.3 [-4.0: 8.6] p = 0.45
    
                                        Lag 0: 2.7 [1.1: 6.5] p = 0.12
                                                                                                              Lag 1:-0.8
                                                                                                              Lag 2: -0.8
                                                                                     -4.9: 3.3] p = 0.65
                                                                                     -4.9: 3.3] p = 0.71
                                                                                                              Lag 0-2 Avg: 2.6 [-2.3: 7.5] p = 0.27
                                                                                                              Leukotriene E4
                                                                                                              Morning avg PMu TEOM
                                                                                                              Height 25percentile: 8.9 [3.0:14.7] p=
                                                                                                              0.004
                                                                                                              Height SOpercentile: 5.9 [1.4:10.4] p =
                                                                                                              0.01
                                                                                                              Height 75percentile: 1.9 [-3.4: 7.3] p =
                                                                                                              0.47
                                                                                                              Model w/o Height x Pollutant: 5.6 [1.0:
                                                                                                              10.2] p = 0.02
                                                                                                              Morning maximum PIfcTEOM
                                                                                                              Height 25percentile: 8.3 [3.4:13.2] p =
                                                                                                              0.001
                                                                                                              Height SOpercentile: 6.1 [2.1:10.2] p=
                                                                                                              0.004
                                                                                                              Height 75 percentile: 3.2 [-2.0: 8.4] p=
                                                                                                              0.23
                                                                                                              Model w/o Height x
                                                                                                              Pollutant: 6.2 [1.9:10.5] p = 0.006
    Reference: Rabinovitch et al. (2004,
    0967531
    
    Periods of Study:
    Nov1999-Mar2000
    
    Nov2000-Mar2001
    
    Nov 2001-Mar 2002
    
    Location: Denver, Colorado
    Outcome: Respiratory symptoms,
    Asthma symptoms (cough and
    wheeze),  Upper respiratory symptoms
    
    Study Design: Time-series
    
    Statistical Analyses: Logistic linear
    regression, PROC Mixed, PROC
    Genmod
    
    Age Groups: 6-12
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Mean (SD): 10.8 (7.1)
    
    Range (Min, Max): (1.8, 53.5)
    Copollutant (correlation):
    CO
    N02
    S02
    PM Increment: 1 pg/m
    
    p(SE)
    
    AM:-0.003 (0.009)
    PM: 0.004 (0.011)
    
    Odds Ratio (Lower Cl, Upper Cl)
    
    Lag
    0.971 (0.843, 1.118)
    0-3 avg.
    December 2009
                                    E-212
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
    Reference: Ranzi et al. (2004, 0895001
    Period of Study: Feb-May 1999
    Location: Emilia-Romagmna, Italy
    (urban-industrial and rural area)
    Outcome: respiratory symptoms, PEF
    measurements, drug consumption and
    daily activity
    Age Groups: Children, mean age=(7.2-
    7.9 yr)
    Study Design: Panel study
    N: 120 children
    Statistical Analyses: Ecological
    analysis and Panel analysis
    Pollutant: PM2 5
    Averaging Time: 24 h
    Mean (SD):
    Urban= 53.07
    Rural=29.11
    Monitoring Stations: 3
    Copollutant (correlation):
    TSP: r=0.613
    PM Increment: 10 pg/m3
    Effect Estimate:
    Urban-industrial panel
    Cough and Phlegm: RR=1.0044
    (1.0011-1.0077)
                                        gender, medicinal use, symptomatic
                                        status of previous day
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: NR
    
                                        Lags Considered: 0,1, 2, 3, 0-3 ma
                                 Daily air pollution concentrations: r=
                                 0.658
    Reference: Rodriguez et al. (2007,
    0928421
    Period of Study: 1996-2003
    Location: Perth, Australia
    Outcome: Body temperature, cough,
    runny/ blocked nose, wheeze/ rattle
    chest (daily)
    Age Groups: Children 0-5 yr old
    Pollutant: PM25
    Averaging Time: 1 h and 24 h
    Mean (SD): 1-h averaging, 20.767
    PM Increment: NR
    [Lower Cl, Upper Cl]
    lag: NR
    LAG :0 day
                                        Study Design: hospital-based cohort
                                        study
    
                                        N: 198-263 children
    
                                        Statistical Analyses: Logistic
                                        regression with GEE and AR (order not
                                        specified) working covariance
    
                                        Covariates: temperature, humidity
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: SAS
    
                                        Lags Considered: 0-5 days
                                 24-h averaging, 8.534
    
                                 Range (Min, Max): 1-h averaging
    
                                 (0.012:93.433)
    
                                 24-h averaging
    
                                 (0.004: 39.404)
    
                                 Monitoring Stations: 10 total, usually
                                 3-5 sites for each pollutant
    
                                 Copollutant (correlation):
    
                                 03
    
                                 NO*
    
                                 CO
                                PM2S, 1-h
                                Body temperature: 1.004 [0.998:1.011]
                                Cough: 1.006 [1.000:1.012]
                                Wheeze/rattle chest:
                                1.004 [0.998:1.010]
                                Runny/blocked nose:
                                0.997 [0.983:1.010]
                                PM2.j, 24-h
                                Body temperature: 1.005 [0.986:1.024]
                                Cough: 1.019 [0.999:1.040]
                                Wheeze/rattle chest:
                                0.990 [0.969:1.012]
                                Runny/blocked nose:
                                0.968 [0.926:1.013]
    
                                LAG: 5 days
                                PM2.j, 1-h
                                Body temperature: 1.005 [0.999:1.040]
                                Cough: 1.003 [0.995:1.010]
                                Wheeze/rattle chest: 1.005 [0.998:
                                10.12]
                                Runny/blocked nose: 1.015 [1.000:
                                1.030]
                                PM2.s, 24-h
                                Body temperature: 1.020 [0.998:1.011]
                                Cough: 1.006 [0.984:1.011]
                                Wheeze/rattle chest:
                                1.018 [0.997:1.040]
                                Runny/blocked nose:
                                1.039 [0.990:1.089]
    
                                LAG: 0-5 days
                                PM2.s, 1-h
                                Body temperature: 1.000 [0.998:1.002]
                                Cough: 1.001 [0.999:1.003]
                                Wheeze/rattle chest:
                                1.002 [1.000:1.004]
                                Runny/blocked nose:
                                1.01  [0.997:1.006]
                                1.02
                                PM2.j, 24-h
                                Body temperature: 1.000 [0.994:1.005]
                                Cough: 1.004 [0.997:1.011]
                                Wheeze/rattle chest:
                                1.001 [0.995:1.007]
                                Runny/blocked nose:
                                0.998 [0.985:1.011]	
    December 2009
                             E-213
    

    -------
                  Study
           Design & Methods
           Concentrations1
      Effect Estimates (95% Cl)
    Reference: Sakai et al. (2004, 0874351
    
    Period of Study:
    Nov1999-Mar2001
    
    Location: Diesel-powered ship from
    Tokyo, Japan to Showa Station on Ongul
    Island, Antarctica for 366 days (from Feb
    1, 2000) and then heading back to
    Japan on Feb1,  2001
    Outcome: circulating leukocyte counts
    and serum inflammatory cytokine levels
    
    Age Groups: 24-57 yr, mean=36.1 + 4.7
    yr
    
    Study Design: Cohort
    
    N: 39 members of 41st Japanese
    Antarctic Research Expedition
    (JARE-41)
    
    Statistical Analyses: ANOVA
    
    Covariates: Smoking history,
    occupational pollutant exposure
    
    Dose-response Investigated? No
    
    Statistical Package: SPSS 11.5J
    Pollutant: PM5.0.2.o
    
    Averaging Time: 24 h
    
    Unit (i.e. ug/m3): particles/L
    
    PM Component: organic and inorganic
    substances, including microorganisms
    
    Copollutant (correlation):
    
    PM2.0-0.3
    
    PMlO-5.0
    Effect Estimate:
    
    Multiple regression analysis between
    inhaled factors in Antarctica
    Total leukocyte
    Cigarette smoking= 0.211, p< 0.001
    Support staff= 0.139, p=0.024
    Total PM= 0.168, p=0.004
    
    Segmented PMN
    Cigarette smoking= 0.015, p=0.805
    Support staff= 0.097, p=0.119
    Total PM= 0.272, p < 0.001
    
    Band-formed PMN
    Cigarette smoking= 0.035, p=0.543
    Support staff= 0.010, p=0.864
    Total PM= 0.470, p < 0.001
    Monocyte
    
    Cigarette smoking= 0.081, p=0.187
    Support staff=-0.019, p=0.759
    Total PM= 0.328, p < 0.001
    
    G-CSF
    Cigarette smoking= 0.131, p < 0.038
    Support staff= 0.176, p=0.005
    Total P M=0.078, p=0.186
    
    IL-6
    Cigarette smoking= 0.182, p=0.004
    Support staff= 0.076, p=0.228
    Total PM= 0.158, p=0.008	
    Reference: Sakai et al. (2004, 0874351
    
    Period of Study: Nov 1999-Mar 28,
    2001
    
    Location: Diesel-powered ship from
    Tokyo, Japan to Showa Station on Ongul
    Island, Antarctica for 366 days (from Feb
    1, 2000) and then heading back to
    Japan on Feb1,  2001
    Outcome: circulating leukocyte counts
    and serum inflammatory cytokine levels
    
    Age Groups: 24-57 yr, mean=36.1 + 4.7
    yr
    
    Study Design: cohort
    
    N: 39 members of 41st Japanese
    Antarctic Research Expedition (JARE-
    41)
    
    Statistical Analyses: ANOVA
    
    Covariates: Smoking history,
    occupational pollutant exposure
    
    Dose-response Investigated? No
    
    Statistical Package: SPSS 11.5J
    Pollutant: PMi0.5.o
    
    Averaging Time: 24 h
    
    Unit (i.e. ug/m3): particles/L
    
    Monitoring Stations: NR
    
    Copollutant (correlation):
    
    PM2.0-0.3
    
    PMlO-5.0
    Effect Estimate:
    
    Multiple regression analysis between
    inhaled factors in Antarctica
    Total leukocyte
    Cigarette smoking= 0.211, p < 0.001
    Support staff= 0.139, p=0.024
    Total PM= 0.168, p=0.004
    
    Segmented PMN
    Cigarette smoking= 0.015, p=0.805
    Support staff= 0.097, p=0.119
    Total PM= 0.272, p < 0.001
    
    Band-formed PMN
    Cigarette smoking= 0.035, p=0.543
    Support staff= 0.010, p=0.864
    Total PM= 0.470, p < 0.001
    
    Monocyte
    Cigarette smoking= 0.081, p=0.187
    Support staff= -0.019, p=0.759
    Total PM= 0.328, p < 0.001
    
    G-CSF
    Cigarette smoking= 0.131, p < 0.038
    Support staff= 0.176, p=0.005
    Total P M=0.078, p=0.186
    
    IL-6
    Cigarette smoking= 0.182, p=0.004
    Support staff= 0.076, p=0.228
    Total PM= 0.158, p=0.008	
    December 2009
                                    E-214
    

    -------
                  Study
           Design & Methods
                                                Concentrations1
                                            Effect Estimates (95% Cl)
    Reference: Silkoff et al. (2005, 0874711  Outcome: Lung function: FEV,, PEF
    Period of Study: Winter 1999-2000,
    Winter 2000-2001
    
    Location: Denver, CO
    Age Groups: Adults (>40 yr-old) with
    COPD, as well as >10 pack-yr tobacco
    use, FEV, < 70%, FEV,/FVC < 60%,
    and no other lung disease
    
    Study Design: COPD patient panel
    study (2 independent panels
    
    One for each winter)
    
    N: 34 subjects (16 1st winter, 18
    second winter)
    
    Statistical Analyses: Mixed effects
    models with first-order, autoregressive,
    ma variance-covariance
    
    Binary outcomes (rescue medication
    use, total symptom score) assessed
    using Poisson regression with GEE and
    first-order, auto-regressive variance-
    covariance
    
    Covariates: Temperature, relative
    humidity, barometric pressure analysis
    run separately for each winter
    
    Season: Wnter
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 0-2 days
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD):
    
    Wnter 1999-2000: 9.0 (5.2)
    
    Wnter 2000-2001:14.3 (9.6)
    Percentiles:
    Wnter 1999-2000
    25th 5.4
    SOth(Median): 7.7
    75th: 11.3
    Wnter 2000-2001
    25th 7.6
    SOth(Median): 11.7
    75th: 17.2
    
    Range (Min, Max):
    Wnter 1999-2000
    (1.8,36.6)
    
    Wnter 2000-2001
    (3.4, 59.6)
    
    Monitoring Stations: multiple sites
    
    Copollutant (correlation):
    
    CO
    
    N02
    
    PM,0
                                                                            PM Increment: SD
    
                                                                            Wnter 1999-2000: 5.2
    
                                                                            Wnter 2000-2001: 9.6
    
                                                                            Model results reported graphically only.
                                                                            No quantitative results reported.
                                                                            Direction of slope (±) and statistical
                                                                            significance (SIG: yes; NS: no) inferred
                                                                            from graphs.
    
                                                                            Among subjects with severe COPD
                                                                            observed in Wnter 1999-2000,
                                                                            statistically significant, but marginal,
                                                                            improvements in PEF associated with
                                                                            morning lag 0 PM25.
    
                                                                            There were no statistically significant
                                                                            associations between rescue
                                                                            medication use and symptom score
                                                                            with PM.
    Reference: Sivacoumar et al. (2006,
    1111151
    Period of Study: Apr 1998-May 1998;
    Sep 1998-Oct 1998
    
    Location: Pammal, India
    Outcome: Respiratory symptoms,
    Decreased pulmonary function
    
    Study Design: Case-control
    
    Statistical Analyses: Poisson
    
    Age Groups: >18
                                        Pollutant: PM25
    
                                        Averaging Time: 24-h avg
                                        The study does not present quantitative
                                        results of association.
    Reference: Slaughter et al. (2003,
    0862941
    
    Period of Study: 1994
    
    Location: Seattle, WA
    Outcome: Asthma attacks, asthma
    severity, medication use
    
    Age Groups: 5.1-13.1 yrold
    
    Study Design: Cross-sectional study
    
    N: 133 children
    
    Statistical Analyses: Ordinal Logistic
    Regression
    
    Poisson Modeling
    
    Covariates: Temperature, Day of the
    Week, Seasonality
    
    Dose-response Investigated? No
    
    Statistical Package: STATA
    
    Lags Considered: 1-, 2-, 3-day lag
                                        Pollutant: PM25
    
                                        Averaging Time:
    
                                        Daily Avg
    
                                        25th: 5.0
    
                                        50th(Median):7.33
    
                                        75th: 11.3
    
                                        Monitoring Stations: 3
    
                                        Copollutant (correlation):
    
                                        PM10 = 0.75
    
                                        CO = 0.82
                                        PM Increment: 10 pg/m  increase
    
                                        RR Estimate [Lower Cl, Upper Cl]
                                        lag:
                                        Inhaler use:
                                        1-day lag: 1.04 (0.98,1.10)
                                        OR Estimate [Lower Cl, Upper Cl]
                                        lag:
                                        Asthma Attack:
                                        1-day lag: 1.20 (1.05,1.37)
                                        Previous day:  1.13 (1.03,1.23)
                                        Medication Use
                                        Nontransition model:
                                        Previous Day: 1.08 (1.01,1.15)
                                        Notes: Figures of estimated odds ratios
                                        for having a more serious asthma
                                        attack for short-term, within-subject
                                        increases in PM25, PM10, and CO.
                                        Transition models additionally control
                                        for the previous day's severity.
    
                                        Figures of estimated relative risks for
                                        having inhaler use for short-term,
                                        within-subject increases in PM25, PM10,
                                        and CO. Transition models additionally
                                        control for the previous day's severity.
    December 2009
                                    E-215
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Strand et al. (2006,
    0892031
    
    Period of Study: 2002-2004
    
    Location: Denver, Colorado, United
    States
    Outcome: Reduced forced expiratory
    volume (FEVi)
    
    Age Groups: 6-12 yr old
    
    Study Design: Mixed model analysis
    (using the default restricted maximum
    likelihood (REML) estimators)
    
    N: 50 children
    
    Statistical Analyses: least squares
    regression, SAS "Output Delivery
    System" (ODS)
    
    Season:  Fall and Winter
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS
    Pollutant: PM25
    
    Averaging Time: Daily
    Mean (SD):
    Outdoor: 12.699 (6.426)
    Indoor: 8.148 (4.348)
    Sulfate/PM25/outdoor: 0.079 (0.067)
    Sulfate/PM25/indoor: 0.074 (0.060)
    Range (Min, Max):
    Mean Personal: (0, 3.035)
    Outdoor: (0, 6.303)
    Indoor: (0,  2.759)
    PM Component: EC, sulfate, nitrate and
    ETS.
    Monitoring Stations: 2 fixed monitors
    and up to 10 personal monitors on a
    given day.
    
    Copollutant (correlation): Sulfate
    (0.63)
    PM Increment: 10 pg/m
    
    Effects Estimate:
    
    Using the estimated slope for the
    validation study model [Lower Cl,  Upper
    Cl] lag:
    
    2.2 percent decrease in FEVi per 10
    pg/m3 increase in ambient PM25 [0.0,
    4.3 decrease] 1 day
    Reference: Tang et al. (2007, 0912691
    
    Period of Study: Dec 2003-Feb 2005
    
    Location: Sin-Chung City, Taipei
    County, Taiwan
    Outcome: Peak expiratory flow rate
    (PEFR) of asthmatic children
    
    Age Groups: 6-12 yr
    
    Study Design: Panel study
    
    N: 30 children
    
    Statistical Analyses: Linear mixed-
    effect models were used to estimate the
    effect of PM exposure on PEFR
    
    Covariates: Gender, age, BMI, history
    of respiratory or atopic disease in
    family, SHS, acute asthmatic
    exacerbation in past 12 mo, ambient
    temp and relative humidity, presence of
    indoor pollutants, and presence of
    outdoor pollutants,
    
    Dose-response Investigated? yes
    
    Statistical Package: S-Plus 2000
    
    Lags Considered: 0-2
    Pollutant: PM25
    
    Averaging Time: 1 h
    
    Mean (SD):
    
    Personal: 27.8 (25.3)
    
    Range (Min, Max):
    
    Personal: 1.4-263.4
    
    Monitoring Stations: 1
    PM Increment: 24.5 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Change in morning PEFR:
                                                                                                                -6.00 (-29.85, 17.85
                                                                                                                -12.52  (-77.93, 52.9
                      lagO
                      Iag1
                                                                                                                -24.87 (-71.49, 21.74) lag 2
                                                                                                                -45.67 (-117.09, 25.74) 2-day mean
                                                                                                                -5.69 (-105.96, 94.59) 3-day mean
    
                                                                                                                Change in evening PEFR:
                                                                                                                0.50 (-18.82, 19.82) lag 0
                                                                                                                16.66 (-7.59, 40.9) lag  1
                                                                                                                11.60 (-11.1,34.31) lag 2
                                                                                                                39.97 (7.1,72.85) 2-day mean
                                                                                                                -3.32 (-66.14, 59.5) 3-day mean
    Reference: Timonen et al. (2004,
    0879151
    Period of Study: Oct 1998-Apr 1999
    Location Amsterdam, Netherlands
    Erfurt, Germany
    Helsinki, Finland
    
    
    
    Outcome: Urinary concentration of Pollutant: PM25
    Clara cell protein CC1 6 of subjects with
    coronary heart disease Averaging Time: 24 h
    Mean (SD)1
    Age Groups: 50+ Amsterdam: 20.03pg/m3
    Study Design: Longitudinal cohort ur7lrt:l23;,l'i9/m/ 3
    study (panel) Helslnkl: 127 «/m
    N: 37 (Amsterdam) Range (Min, Max):
    Amsterdam: 3.8-82.2
    47 (Erfurt) Erfurt: 4.5-118.1
    Helsinki: 3. 1-39.8
    PM Increment: 10 pg/m3
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Pooled estimate;
    2.8 (-1.1-6.7) lag 0
    2.9 (-0.6-6.5) lag 1
    5.0 (-2.4-12.4) lag 2
    1.6 (-4.7-7.9) lag 3
    9.7 (-6.0-25.4) 5-day mean
    
    CC16 was not associated to PM25
                                        47 (Helsinki)
    
                                        Statistical Analyses: The response of
                                        interest was log transformed, creatinine
                                        adjusted CC16. Mixed-effect model was
                                        used to investigate the association
                                        between CC16 and air pollutants.
    
                                        Covariates: Subjects, long term time
                                        trend, temperature (lags 0-3), relative
                                        humidity (lags 0-3), barometric pressure
                                        (lags 0-3), and weekday of visit.
    
                                        Dose-response Investigated? yes
    
                                        Statistical Package: S-Plus and SAS
    
                                        Lags Considered: 0-3
                                        Monitoring Stations: 3
    
                                        Copollutant (correlation):
                                        Spearman Correlation:
                                        NC 0.01 -0.1: Amsterdam -0.15
                                        Erfurt 0.62
                                        Helsinki 0.14
                                        NCO.1-1.0: Amsterdam 0.80
                                        Erfurt 0.84
                                        Helsinki 0.80
                                        N02: Amsterdam 0.49
                                        Erfurt 0.82
                                        Helsinki 0.35
                                        CO: Amsterdam 0.58
                                        Erfurt 0.77
                                        Helsinki 0.40
                                        in the pooled analysis but CC16 was
                                        significantly associated to PM25
                                        in Helsinki:
                                        23.3 (6.3-40.3) lag 0
                                        6.4 (-8.2-21.1) lag 1
                                        20.2 (6.9-33.5) lag 2
                                        17.6 (4.3-30.9) lag 3
                                        38.8 (15.8-61.8) 5-day mean
    December 2009
                                     E-216
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Trenga et al. (2006,
    1552091
    
    Period of Study: 1999-2002
    
    Location: Seattle, WA
    Outcome: Lung function: FEVi, PEF,
    MMEF (maximal midexpiratory flow
    
    assessed only for children)
    
    Age Groups: Adults (56-89-yr-old)
    healthy & with COPD
    
    Asthmatic children 6-13-yr-old
    
    Study Design: Adult and pediatric
    panel study over 3 yr with 1 monitoring
    period ("session") per yr
    
    N: 57 adults (33 healthy, 24 with COPD)
    = 692 subject-days = 207 study-days
    
    17 asthmatic children = 319 subject-
    days = 98 study-days
    
    Statistical Analyses: Mixed effects,
    longitudinal regression models, with the
    effects of pollutant decomposed into
    each subject's
    
    a) overall mean
    
    b) Difference between their session-
    specific mean and overall mean
    
    c) Difference between their daily values
    and session-specific mean
    
    Covariates: Gender, age, ventral site
    temperature and relative humidity, CO,
    N02
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 0-1 days
    Pollutant: PM25
    Averaging Time: 24 h
    Percentiles:
    Children
    Personal
    25th: 8.1
    SOth(Median): 11.3
    75th: 16.3
    Indoor
    25th: 5.7
    SOth(Median): 7.5
    75th: 10.2
    Local outdoor
    25th: 6.4
    SOth(Median): 9.6
    75th: 14.
    
    Adults
    Personal
    25th: 5.9
    SOth(Median): 8.5
    75th: 12.4
    Indoor
    25th: 5.1
    SOth(Median): 7.6
    75th: 10.8
    Local outdoor
    25th: 6
    SOth(Median): 8.6
    75th: 13.1
    
    Range (Min, Max):
    Children, Personal 1.0,  49.4
    Indoor (2.2, 36.3)
    Local outdoor (2.8, 40.4)
    Adults,  Personal 1.3, 66.6
    lndoor(1.6, 65.3)
    Local outdoor (0.0, 41.5)
    
    Monitoring Stations: 2
    also subject-specific local outdoors (i.e.
    at each home), indoor, and personal
    
    Copollutant (correlation):
    CO
    N02
    PM25
    PMio-2.s (coarse)
    PM Increment: 10 pg/m
    
    ADULT
    Personal PM2 5-FEV,
    Overall: Lag 0-6.0 [-29.1:17.2]
    Lag1  12.0 [-12.9: 36.9]
    No-COPD: Lag 0-4.6 [-31.0: 21.9]
    Lag 1  19.3 [-8.2: 46.7]
    COPD: Lag 0-10.2 [-55.8: 35.4]
    Lag 1-19.0 [-74.1: 36.2]
    PEF: Lag 01.5 [-2.2: 5.2]
    Lag1  2.1 [-1.9:6.1]
    No-COPD: Lag 03.4 [-0.9: 7.6]
    Lag1  1.9 [-2.5: 6.3]
    COPD: Lag 0-4.3 [-11.5: 3.0]
    Lag 12.6 [-6.3:11.5]
    Indoor PM2 5-FEV,
    Overall: Lag 0-12.8 [-44.5:19.0]
    Lag1  19.4 [-11.3: 50.1]
    No-COPD: Lag 0-15.8  [-50.0:18.4]
    Lag1  28.4[-4.6:61.3]
    COPD: Lag 02.6 [-71.7: 76.8]
    Lag 1-29.7 [-102.9: 43.5]
    PEF
    Overall: Lag 0-0.5 [-5.6: 4.6]
    Lag 1  2.3 [-3.3: 7.8]
    No-COPD: Lag 00.1 [-5.4:5.6]
    Lag 1  2.5 [-3.5: 8.4]
    COPD: Lag 0-3.2 [-15.1: 8.7]
    Lag1  1.1 [-12.0:14.3]
    Outdoor Home PM2 5-FEV,
    Overall: Lag 0-1.4 [-35.6: 32.7]
    Lag 1  -2.4 [-37.6: 32.7], No-COPD: Lag
    01.5 [-36.1:39.2]
    Lag 1  10.7 [-26.9: 48.4]
    COPD: Lag 0 -8.9 [-62.2: 44.4]
    Lag 1-45.2 [-102.6:12.1]
    PEF
    Overall: Lag 02.3 [-3.3: 7.9]
    Lag 1  0.4 [-5.6: 6.4]
    No-COPD: Lag 04.0 [-2.2:10.1]
    Lag 1  2.0 [-4.4: 8.4]
    COPD: Lag 0-1.8 [-10.6: 6.9]
    Lag 1-4.8 [-14.6: 4.9]
    Central Sites PM25 -FEV,
    Overall: Lag 0-35.5 [-70.0:-1.0]
    Lag 1  -40.4 [-71.1: -9.6], No-COPD: Lag
    0-32.6 [-69.5: 4.3]
    Lag 1  -29.0 [-62.5: 4.5]
    COPD: Lag 0 -43.6 [-95.0: 7.8]
    Lag1  -70.8 [-118.4: 23.1]
    PEF
    Overall: Lag 01.5 [-4.2: 7.1]
    Lag 1  -2.3 [-7.4: 2.9]
    No-COPD: Lag 02.5 [-3.5: 8.6]
    Lag 1-0.5 [-6.1:5.0]
    COPD: Lag 0-1.5 [-9.9: 6.9]
    Lag 1-7.1 [-15.0: 0.9]
    PEDIATRIC FEV,
    Personal PM25
    Overall:
    Lag 0-13.08 [-38.26: 12.10]
    Lag1  -16.12 [-42.61: 10.37],
    No anti-inflammatory medication:
     Lag 0-41.73 [-94.31:10.84]
    Lag!  -30.99 [-82.17: 20.19],
    Anti-inflammatory medication:
    Lag 0  -4.61 [-34.49: 25.28]
    Lag1  -10.87 [-45.01: 23.27]
    Indoor PM2 5
    Overall:
                                                                                                                Lag 0 -45.90
                                                                                                                Lag 1 -64.78
                                                                                        -89.92: 1.88]
                                                                                        -111.27:18.2!
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0 -75.92
                                                                                                                Lag 1 -65.08
                                                                                        -145.16:6.6'
                                                                                        -136.98: 6.82],
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0-28.50 [-94.72: 37.71]
    December 2009
                                    E-217
    

    -------
                  Study                       Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                                Lag1 -64.60-147.23:18.04]
                                                                                                                Outdoor Home P f.l; :
                                                                                                                Overall:
                                                                                                                Lag 0-13.11 [-57.41:31.19]
                                                                                                                Lag 1 -9.37 [-54.73: 36.00],
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0-24.42 [-81.22: 32.38]
                                                                                                                Lag 1 16.52 [-45.76: 78.80],
                                                                                                                Anti-inflammatory medication:
                                                                                                                 Lag 0-3.59 [-75.88: 68.70]
                                                                                                                Lag 1-26.76 [-89.53: 36.01]
                                                                                                                Central Sites PM25.
                                                                                                                Overall:
                                                                                                                Lag 0-12.32 [-53.21: 28.56]
                                                                                                                Lag 1 5.75 [-33.27: 44.76],
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0 -33.59 [-89.99: 22.82]
                                                                                                                Lag 131.30 [-29.91: 92.51]
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0-2.13 [-71.99: 67.73]
                                                                                                                Lag 1 -3.53 [-67.32: 60.27]
                                                                                                                PEF:
                                                                                                                Personal PM25
                                                                                                                Overall:
                                                                                                                Lag 0 0.31 [-4.02: 4.64]
                                                                                                                Lag1 -2.19 [-6.49:  2.12]
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0 0.22 [-8.85: 9.29]
                                                                                                                Lag! -10.48 [-18.68: 2.28]
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0 0.34 [-4.67: 5.35]
                                                                                                                Lag1 0.74 [-4.21: 5.69]
                                                                                                                Indoor PM2 5
                                                                                                                Overall:
                                                                                                                Lag 0-8.68 [-16.64:-0.72
                                                                                                                Lag 1-9.22 [-17.51:-0.93;
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0-13.34
                                                                                                                Lag1 -17.13
    -25.90: -0.79]
    -29.86: 4.41],
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0-5.98 [-15.85: 3.89]
                                                                                                                Lag 1-4.19 [-14.59: 6.20]
                                                                                                                Outdoor Home P f.l :
                                                                                                                Overall:
                                                                                                                Lag 0-6.27 [-14.07:1.53]
                                                                                                                Lag1 -5.64 [-13.73: 2.44],
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0-7.52 [-17.56: 2.51]
                                                                                                                Lag 1-6.92 [-18.03: 4.19],
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0-5.22 [-14.77: 4.34]
                                                                                                                Lag 1-4.78 [-14.42: 4.86]
                                                                                                                Central Sites Pf.l; :
                                                                                                                Overall:
                                                                                                                Lag 0-5.62 [-12.86:1.62]
                                                                                                                Lag 1 -2.45 [-9.34: 4.43],
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0-6.32 [-16.31: 3.68]
                                                                                                                Lag! -0.83[-11.60: 9.95]
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0-5.29 [-13.42: 2.85]
                                                                                                                Lag1 -3.04-10.76:4.67
                                                                                                                MMEF
                                                                                                                Personal PM25
                                                                                                                Overall:
                                                                                                                Lag 0-0.99 [-3.96:1.98]
                                                                                                                Lag1 -1.08 [-4.05:1.88],
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0 -3.32 [-9.52: 2.88]
                                                                                                                Lag 1 -2.49 [-8.23: 3.25],
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0-0.31 [-3.77: 3.16]
                                                                                                                Lag 1 -0.59 [-4.06: 2.89]
                                                                                                                Indoor PM2 5
                                                                                                                Overall: Lag 0-3.29 [-8.52:1.94]
                                                                                                                Lagl -11.08 [-16.26: 5.90].
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0-12.65 [-20.74:-4.56]'Lag 1-
    December2009                                                    E-218
    

    -------
                  Study
           Design & Methods
           Concentrations1
       Effect Estimates (95% Cl)
                                        Covariates: Gender, age, BMI, history
                                        of respiratory or atopic disease in family,
                                        SHS, acute asthmatic exacerbation in
                                        past 12 mo, ambient temp and relative
                                        humidity, presence of indoor pollutants,
                                        and presence of outdoor pollutants,
    
                                        Dose-response Investigated? Yes
    
                                        Statistical Package: S-Plus 2000
    
                                        Lags Considered: 0-2
                                                                                                                13.84 [-21.82: 5.85]
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 02.14 [-4.17: 8.45]
                                                                                                                Lag 1-9.33 [-15.89:-2.78]
                                                                                                                Outdoor Home P f.l; :
                                                                                                                Overall:
                                                                                                                Lag 0-4.13 [-9.28:1.01]
                                                                                                                Lag 1 -0.73 [-6.02: 4.56]
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0-8.23 [-14.77:1.69]
                                                                                                                Lag! -1.19[-8.45: 6.07]
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 0 -0.68 [-6.87: 5.50]
                                                                                                                Lag 1 -0.42 [-6.72: 5.87]
                                                                                                                Central Sites PM25.
                                                                                                                Overall:
                                                                                                                Lag 0-2.10 [-6.99: 2.79
                                                                                                                Lag 1-0.12 [-4.67: 4.42
                                                                                                                No anti-inflammatory medication:
                                                                                                                Lag 0-8.21 [-14.79:1.62]
                                                                                                                Lag 1 -0.22 [-7.34: 6.90]
                                                                                                                Anti-inflammatory medication:
                                                                                                                Lag 00.82 [-4.48: 6.12],
                                                                                                                Lag 1-0.09 [-5.19: 5.01]
    Reference: Tang et al. (2007, 0912691
    Period of Study: Dec 2003-Feb 2005
    Location: Sin-Chung City, Taipei
    County, Taiwan
    Outcome: Peak expiratory flow rate
    (PEFR) of asthmatic children
    Age Groups: 6-12 yr
    Study Design: Panel study
    N: 30 children
    Statistical Analyses: Linear mixed-
    effect models were used to estimate the
    effect of PM exposure on PEFR
    Pollutant: PM25.i
    Averaging Time: 1 h
    Mean (SD):
    Personal: 6.2 (4.8)
    Range (Min, Max):
    Personal: 0.3-86.8
    Monitoring Stations: 1
    No quantitative effects reported.
    Reference: Tang et al. (2007, 0912691
    
    Period of Study: Dec 2003-Feb 2005
    
    Location: Sin-Chung City, Taipei
    County, Taiwan
    Outcome: Peak expiratory flow rate
    (PEFR) of asthmatic children
    
    Age Groups: 6-12 yr
    
    Study Design: Panel study
    
    N: 30 children
    
    Statistical Analyses: Linear mixed-
    effect models were used to estimate the
    effect of PM exposure on PEFR
    
    Covariates: Gender, age, BMI, history
    of respiratory or atopic disease in family,
    SHS, acute asthmatic exacerbation in
    past 12 mo, ambient temp and relative
    humidity, presence of indoor pollutants,
    and presence of outdoor pollutants,
    
    Dose-response Investigated? yes
    
    Statistical Package: S-Plus 2000
    
    Lags Considered: 0-2
    Pollutant: PM1
    
    Averaging Time: 1 h
    
    Mean (SD):
    
    Personal: 34.0 (28.9)
    
    Ambient: 31.4 (18.8)
    
    Range (Min, Max):
    
    Personal: 1.8-284.6
    
    Ambient: 0.1-128.4
    
    Monitoring Stations:  1
    PM Increment: 27.6 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Change in morning PEFR:
    -6.44 (-30.18, 17.29) lag 0
    -12.26 (-77.6, 53.09) lag 1
    -4.38 (-54.79, 46.03) lag 2
    -44.06 (-113.79, 25.67) 2-day mean
    -6.01 (-101.48, 89.46)  3-day mean
    
    Change in evening PEFR:
    1.17 (-17.79, 20.13) lag 0
    -4.98 (-27.77, 17.81) lag 1
    11.30 (-11.55, 34.16) lag 2
    41.74(11.36, 72.13) 2-day mean
    28.21 (-19.08, 75.5) 3-day mean
    December 2009
                                    E-219
    

    -------
    Study
    Reference: Timonen et al. (2004,
    0879151
    Period of Study: Oct 1998-Apr 1999
    Location:
    Amsterdam, The Netherlands
    Erfurt, Germany
    Helsinki, Finland
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Timonen et al. (2004,
    0879151
    Period of Study: Oct 1998-Apr 1999
    Location :
    Amsterdam, The Netherlands
    Erfurt, Germany
    Helsinki, Finland
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Urinary concentration of
    Clara cell protein CC16 of subjects with
    coronary heart disease
    Age Groups: 50+
    Study Design: Longitudinal cohort
    study (panel)
    N:
    N=37 (Amsterdam)
    N=47 (Erfurt)
    N=47 (Helsinki)
    Statistical Analyses: The response of
    interest was log transformed, creatinine
    adjusted CC16. Mixed-effect model was
    used to investigate the association
    between CC16 and air pollutants.
    
    Covariates: Subjects, long term time
    trend, temperature (lags 0-3), relative
    humidity (lags 0-3), barometric pressure
    (lags 0-3), and weekday of visit.
    
    Dose-response Investigated? yes
    Statistical Package:
    S-Plus and SAS
    Lags Considered: 0-3
    Outcome: Urinary concentration of
    Clara cell protein CC16 of subjects with
    coronary heart disease
    Age Groups: 50+
    Study Design: Longitudinal cohort
    study (panel)
    N:
    N=37 Amsterdam)
    N=47 Erfurt)
    N=47 (Helsinki)
    Statistical Analyses: The response of
    interest was log transformed, creatinine
    adjusted CC16. Mixed-effect model was
    used to investigate the association
    between CC16 and air pollutants.
    
    Covariates: Subjects, long term time
    trend, temperature (lags 0-3), relative
    humidity (lags 0-3), barometric pressure
    (lags 0-3), and weekday of visit.
    Dose-response Investigated? Yes
    Statistical Package: S-Plus and SAS
    Lags Considered: 0-3
    
    
    
    
    
    
    
    Concentrations1
    Pollutant: NC 0.01 -0.1
    Averaging Time: 24 h
    Mean (SD):
    Amsterdam: 17338 /cm3
    Erfurt: 21124 /cm3
    Helsinki: 17041 /cm3
    Range (Min, Max):
    Amsterdam: 5699-37 195
    Erfurt: 3867-96678
    Helsinki: 2305-50306
    Unit (i.e. pg/m3): 1/cm3
    Monitoring Stations: 3
    PM25:
    Amsterdam -0.1 5
    Erfurt 0.62
    Helsinki 0.1 4
    N02:
    Amsterdam 0.49
    Erfurt 0.82
    Helsinki 0 72
    CO:
    Amsterdam 0.22
    Erfurt 0.72
    Helsinki 0.35
    
    Pollutant: NC1 0-0.1
    Averaging Time: 24 h
    Mean (SD):
    Amsterdam: 2131 /cm3
    Erfurt: 1829 /cm3
    Helsinki: 1390 /cm3
    Range (Min, Max):
    Amsterdam: 413-6413
    Erfurt: 303-6848
    Helsinki: 344-3782
    Unit (i.e. pg/m3): 1/cm3
    
    Monitoring Stations: 3
    Copollutant (correlation):
    Spearman Correlation:
    NC 0.1-0.01:
    Amsterdam 0.1 6
    Erfurt 0.67
    Helsinki 0.53
    PM25:
    Amsterdam 0.80
    Erfurt 0.84
    Helsinki 0 80
    N02:
    Amsterdam 0.67
    Erfurt 0.82
    Helsinki 0.72
    CO:
    Amsterdam 0.60
    Erfurt 0.78
    Helsinki 0.51
    Effect Estimates (95% Cl)
    PM Increment: 10,000 /cm3
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Pooled estimate;
    1.7 (-4.4-7.8) lag 0
    -1.8 (-8.3-4.6) lag 1
    1.5 (-5.6-8.6) lag 2
    2.3 (-4.8-9.3) lag 3
    1.8 (-9.4-13.0) 5-day mean
    There was no association between NC
    0.01-0.1 and CC16 in the pooled
    analysis.
    
    
    
    
    
    
    
    
    
    PM Increment: 1000 /cm3
    RR Estimate [Lower Cl, Upper Cl] lag:
    Pooled estimate;
    4.3 (-1.4-10.0) lag 0
    5.1 (-0.6-10.7) lag 1
    4.5 (-0.5-9.6) lag 2
    1.6 (-3.5-6.7) lag 3
    13.1 (-4.3-30.5) 5-day mean
    CC16 was not associated to NC 0.1-1.0
    in the pooled analysis but CC16 was
    significantly associated to NC 0.1-1.0 in
    Helsinki:
    15.5 (0.001 -30.9) lag 0
    10.8 (-4.2-25.8) lag 1
    10. 5 9-4. 1-25.1) lag 2
    17.4 (3.4-31. 4) lag 3
    43.2 (17.4-69.0) 5-day mean
    
    
    
    
    
    
    
    December 2009
    E-220
    

    -------
                  Study
           Design & Methods
           Concentrations1
       Effect Estimates (95% Cl)
    Reference: von Klot et al. (2002,
    0347061
    
    Period of Study: Sep 1996-Mar 1997
    (winter)
    
    Location: Erfurt, Germany
    Outcome: Asthma symptoms
    (wheezing, shortness of breath at rest,
    waking up with breathing problems, or
    coughing without having a cold) and
    Asthma medication (inhaled short-acting
    IS2- agonists, inhaled long-acting IJ2-
    agonists,  inhaled corticosteroids,
    cromolyn sodium, theophylline, oral
    corticosteroids, and N-acetylcysteine)
    
    Age Groups: Adults, mean=59.0 yr and
    range =37-77 yr
    
    Study Design: Panel study
    
    N: 53 adult asthmatics
    
    Statistical Analyses: Logistic
    regression models
    
    Covariates: Seasonal variation in
    medication use or symptom prevalence,
    meteorological factors (relative humidity,
    temperature), weekend, Christmas
    holidays
    
    Season: Winter
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered:0,1,2,3,4,5,6,7,
    8, 9,10, ma calculated from same day
    and preceding days
    Pollutant: MCO.5-0.1
    
    Averaging Time: 10-min intervals
    Mean (SD): 24.8
    Percentiles:
    25th: 11.4
    SOth(Median): 19.6
    75th: 33.1
    Range (Min, Max): (2.4-108.3)
    Copollutant (correlation):
    PM10.25:r=0.51
    NCO. 1-0.01 :r= 0.45
    NC0.5-0.1:r=0.95
    NC2.5-0.5: r= 0.92
    MC2.5-0.01:r=1.00
    PMi0:r=0.91
    N02: r= 0.69
    CO: r= 0.66
    SO,: r= 0.60
    NC Increment: 1 IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Association between the prevalence of
    inhaled B2- agonist use and MCO. 1-0.5
    
    Same day, IQR=21,
    OR= 0.98 (0.92-1.04)
    5-day mean, IQR= 21
    OR= 1.11 (1.02-1.20)
    14-day mean IQR= 17,
    OR=1.01 (0.93-1.10)
    
    Association between the prevalence of
    inhaled corticosteroid use and
    MCO. 1-0.5
    
    Same day, IQR= 2,
    OR= 1.09 (1.02-1.17)
    5-day mean IQR=21,
    OR= 1.28 (1.18-1.39)
    14-day mean, IQR=17,
    OR= 1.49 (1.38-1.61)
    
    Association between the prevalence of
    wheezing and MCO.1-0.5
    Same day, IQR=21,
    OR= 1.01 (0.94-1.08)
    5-day mean, IQR=21,
    OR= 1.08 (0.99-1.17)
    14-day mean, IQR=17,
    OR= 1.05 (0.96-1.15)
    Reference: von Klot et al. (2002,
    0347061
    
    Period of Study: Sep 1996-Mar 1997
    (winter)
    
    Location: Erfurt, Germany
    Outcome: Asthma symptoms
    (wheezing, shortness of breath at rest,
    waking up with breathing problems, or
    coughing without having a cold) and
    Asthma medication (inhaled short-acting
    B2- agonists, inhaled long-acting B2-
    agonists,  inhaled corticosteroids,
    cromolyn sodium, theophylline, oral
    corticosteroids, and N-acetylcysteine)
    
    Age Groups: Adults, mean=59.0 yr and
    range =37-77 yr
    
    Study Design: Panel study
    
    N: 53 adult asthmatics
    
    Statistical Analyses: Logistic
    regression models
    
    Covariates: Seasonal variation in
    medication use or symptom prevalence,
    meteorological factors (relative humidity,
    temperature), weekend, Christmas
    holidays
    
    Season: Winter
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered:0,1,2,3,4,5,6,7,
    8, 9,10, ma calculated from same day
    and preceding days
    Pollutant: MC2.5-0.01
    
    Averaging Time: 10-min intervals
    
    Mean (SD): 30.3
    
    Percentiles:
    
    25th: 13.5
    
    SOth(Median): 24.6
    
    75th: 41.3
    
    Range (Min, Max): (3.6-133.8)
    
    Copollutant (correlation):
    
    PMio-25: r= 0.52
    
    NC0.5-o.i: r=0.45
    
    NC25.o5: r= 0.94
    
    MCo.5-o.i:r=1.00
    
    NC0.i-0.oi:r=0.45
    
    PM10:r=0.94
    
    N02: r= 0.68
    
    CO: r= 0.65
    
    S02: r= 0.62
    NC Increment: 1 IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Association between the prevalence of
    inhaled B2- agonist use and MC0.01-
    2.5
    
    Same day, IQR= 28, OR= 0.96 (0.90-
    1.04)
    5-day mean, IQR= 26 , OR= 1.10 (1.01-
    1.20)
    14-day mean, IQR=20, OR= 1.03
    (0.95-1.12)
    December 2009
                                    E-221
    

    -------
                  Study
           Design & Methods
           Concentrations1
       Effect Estimates (95% Cl)
    Reference: von Klot et al. (2002,
    0347061
    
    Period of Study: Sep 1996-Mar 1997
    (winter)
    
    Location: Erfurt, Germany
    Outcome: Asthma symptoms
    (wheezing, shortness of breath at rest,
    waking up with breathing problems, or
    coughing without having a cold) and
    Asthma medication (inhaled short-acting
    IS2- agonists, inhaled  long-acting IJ2-
    agonists,  inhaled corticosteroids,
    cromolyn sodium, theophylline, oral
    corticosteroids, and N-acetylcysteine)
    
    Age Groups: Adults,  mean=59.0 yr and
    range =37-77 yr
    
    Study Design: Panel study
    
    N: 53 adult asthmatics
    
    Statistical Analyses: Logistic
    regression models
    
    Covariates: Seasonal variation in
    medication use or symptom prevalence,
    meteorological factors (relative humidity,
    temperature), weekend, Christmas
    holidays
    
    Season: Winter
    
    Dose-response Investigated? No
    
    Statistical Package:  NR
    
    Lags Considered:0,1,2,3,4,5,6,7,
    8, 9,10, ma calculated from same day
    and preceding days
    Pollutant: NCO. 1-0.01
    
    Averaging Time: 10-min intervals
    
    Mean (SD): 17,300/cm3
    
    Percentiles:
    
    25th: 9286
    
    SOth(Median): 16940
    
    75th: 24484
    
    Range (Min, Max): (3272-46195)
    
    Unit (i.e. pg/m3):  1/cm3
    
    Copollutant (correlation):
    
    PM10.2.5:  r= 0.41
    
    NC0.5-o.i: r=0.55
    
    NC25.o5: r= 0.34
    
    MC0.5.0,:r=0.45
    
    MC2.5-o.oi:r=0.45
    
    PMi0:r=0.51
    
    N02: r= 0.66
    
    CO: r= 0.66
    
    SO,: r= 0.36
    NC Increment: 1 IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Association between the prevalence of
    inhaled B2- agonist use and NCO.01-0.1
    Same day, IQR= 15000,
    OR= 0.97 (0.90-1.04)
    5-day mean, IQR= 10000,
    OR= 1.11 (1.01-1.21)
    14-day mean, IQR=7700,
    OR= 1.08 (0.96-1.21)
    Association between two pollutants,
    jointly in one model, and the
    Outcomes
    Inhaled short-acting B2- agonist use
    NCO. 1-0.01 OR= 1.07 (0.97-1.18)
    MC0.5-0.1:OR= 1.07 (0.98-1.18)
    
    Inhaled corticosteroid use
    NCO. 1-0.01 OR= 1.01 (0.87-1.18)
    MC0.5-0.1:OR= 1.53 (1.39-1.69)
    
    Wheezing
    NCO. 1-0.01 OR= 1.12 (1.01-1.24)
    MC0.5-0.1:OR= 1.02 (0.92-1.12)
    
    Association between the prevalence of
    inhaled corticosteroid use and NCO.01-
    0.1
    
    Same day, IQR= 15000,
    OR= 1.07 (1.00-1.15)
    5-day mean, IQR= 10000,
    OR= 1.22 (1.12-1.33)
    14-day mean, IQR=7700,
    OR= 1.45 (1.29-1.63)
    
    Association between the prevalence of
    wheezing and NCO. 1-0.01
    Same day, IQR= 15000,
    OR= 0.94 (0.86-1.01)
    5-day mean, IQR= 10000,
    OR= 1.13 (1.03-1.24)
    14-day mean, IQR=7700,
    OR= 1.27 (1.13-1.43)
    
    Association between the prevalence of
    respiratory symptoms and NCO.1-0.01
    Attack of shortness of breath and
    wheezing
    Same day, IQR= 15000,
    OR= 1.01 (0.91-1.12)
    5-day mean, IQR= 10000,
    OR= 1.08 (0.96-1.21)
    14-day mean, IQR=7700,
    OR= 1.26 (1.08-1.48)
    
    Walking up with breathing problems
    Same day, IQR= 15000,
    OR= 1.04 (0.96-1.13)
    5-day mean, IQR= 10000,
    OR= 1.09 (0.99-1.19)
    14-day mean, IQR=7700,
    OR= 1.26 (1.13-1.41)
    
    Shortness of breath
    Same day, IQR= 15000,
    OR= 0.98 (0.90-1.06)
    5-day mean, IQR= 10000,
    OR= 1.09 (0.99-1.19)
    14-day mean, IQR=7700,
    OR= 1.24 (1.11-1.40)
    
    Phlegm
    Same day, IQR= 15000,
    OR=1.01 (0.94-1.09)	
    December 2009
                                   E-222
    

    -------
                  Study
           Design & Methods
           Concentrations1
       Effect Estimates (95% Cl)
                                                                                                             5-day mean, IQR= 10000,
                                                                                                             OR=1.11 (1.02-1.21)
                                                                                                             14-day mean, IQR=7700,
                                                                                                             OR= 1.11(0.99-1.25)
    
                                                                                                             Cough
                                                                                                             Same day, IQR= 15000,
                                                                                                             OR= 1.07 (0.98-1.16)
                                                                                                             5-day mean, IQR= 10000,
                                                                                                             OR= 1.17 (1.07-1.28)
                                                                                                             14-day mean, IQR=7700,
                                                                                                             OR= 1.20 (1.06-1.35)
    Reference: von Klot et al. (2002,
    0347061
    
    Period of Study: Sep 1996-Mar 1997
    (winter)
    
    Location: Erfurt, Germany
    Outcome: Asthma symptoms
    (wheezing, shortness of breath at rest,
    waking up with breathing problems, or
    coughing without having a cold) and
    Asthma medication (inhaled short-acting
    IS2- agonists, inhaled long-acting IJ2-
    agonists, inhaled corticosteroids,
    cromolyn sodium, theophylline, oral
    corticosteroids, and N-acetylcysteine)
    
    Age Groups: Adults, mean=59.0 yr and
    range =37-77 yr
    
    Study Design: Panel study
    
    N: 53 adult asthmatics
    
    Statistical Analyses: Logistic
    regression models
    
    Covariates: Seasonal variation in
    medication use or symptom prevalence,
    meteorological factors (relative humidity,
    temperature), weekend, Christmas
    holidays
    
    Season: Winter
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered:0,1,2,3,4,5,6,7,
    8, 9,10, ma calculated from same day
    and preceding days
    Pollutant: NCO.5-0.1
    
    Averaging Time: 10-min intervals
    
    Mean (SD): 2005/cm3
    
    Percentiles:
    
    25th: 958
    
    SOth(Median): 1610
    
    75th: 2767
    
    Range (Min, Max): (291 -6700)
    
    Unit (i.e. pg/m3):  1/cm3
    
    Copollutant (correlation):
    
    PM10.25:  r= 0.50
    
    NC0.i-0.oi:r=0.55
    
    NC2.5-o.5: r= 0.76
    
    MC0 5.0 ,:r= 0.95
    
    MC25-ooi:r=0.93
    
    PM10:r=0.85
    
    N02: r= 0.75
    
    CO: r= 0.79
    
    S02: r= 0.51
    NC Increment: 1 IQR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Association between the prevalence of
    inhaled IS2- agonist use and NCO.5-0.1
    Same day, IQR=1800,
    OR= 0.99 (0.92-1.05)
    5-day mean, IQR= 1500,
    OR= 1.10 (1.03-1.19)
    14-day mean, IQR=1450,
    OR= 0.95 (0.86-1.05)
    
    Association between the prevalence of
    inhaled corticosteroid use and NCO.5-
    0.1
    Same day, IQR=1800,
    OR= 1.06 (0.99-1.14)
    5-day mean, IQR= 1500,
    OR= 1.23 (1.14-1.32)
    14-day mean, IQR=1450,
    OR=1.51 (1.37-1.67)
    
    Association between the prevalence of
    wheezing and NCO.5-0.1
    Same day, IQR=1800,
    OR= 1.00 (0.93-1.07)
    5-day mean, IQR= 1500,
    OR= 1.08 (1.00-1.17)
    14-day mean, IQR=1450,
    OR=1.11 (1.00-1.24)
    December 2009
                                   E-223
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: von Klot et al. (2002,
    0347061
    Period of Study: Sep 1996-Mar 1997
    (winter)
    Location: Erfurt, Germany
     Outcome: Asthma symptoms
     (wheezing, shortness of breath at rest,
     waking up with breathing problems, or
     coughing without having a cold) and
     Asthma medication (inhaled short-acting
     IS2- agonists, inhaled long-acting IJ2-
     agonists, inhaled corticosteroids,
     cromolyn sodium, theophylline, oral
     corticosteroids, and N-acetylcysteine)
     Age Groups: Adults, mean=59.0 yr and
     range =37-77 yr
     Study Design: Panel study
     N: 53 adult asthmatics
     Statistical Analyses: Logistic
     regression models
     Covariates: Seasonal variation in
     medication use or symptom prevalence,
     meteorological factors (relative humidity,
     temperature), weekend,  Christmas
     holidays
     Season: Winter
     Dose-response Investigated? No
     Statistical Package: NR
     Lags Considered:0,1,2,3,4,5,6,7,
     8, 9,10, ma calculated from same day
     and preceding days
     Pollutant: NC2.5-0.5
     Averaging Time: 10-min intervals
     Mean (SD): 21.4/cm3
     Percentiles:
     25th: 5.6
     SOth(Median): 13.0
     75th: 31.6
     Range (Min, Max): (0.9-127.6)
     Unit (i.e. pg/m3): 1/cm3
     Copollutant (correlation):
     PM10.25: r= 0.48
     NC0.i-0.oi:r=0.34
     NC0 5-0 a= 0.76
     MC0 5.0 ,:r= 0.92
     MC2.5-o.oi:r=0.94
     PM10:r=0.88
     N02: r= 0.54
     CO: r= 0.46
     SO,: r= 0.66
    NC Increment: 1  IQR
    Effect Estimate [Lower Cl, Upper Cl]:
    Association between the prevalence of
    inhaled B2- agonist use and NC2.5-0.5
    Same day, IQR= 26, OR= 0.99 (0.93-
    1.05)
    5-day mean, IQR= 22, OR= 1.09 (1.01-
    1.17)
    14-day mean, IQR= 17, OR= 1.08
    (1.02-1.15)
    Association between the prevalence of
    inhaled corticosteroid use and NC2.5-
    0.5
    Same day, IQR= 26, OR= 1.13 (1.06-
    1.21)
    5-day mean, IQR= 22, OR= 1.28 (1.19-
    1.37)
    14-day mean, IQR= 17, OR= 1.44
    (1.36-1.53)
    Association between the prevalence of
    wheezing and NC2.5-0.5
    Same day, IQR= 26, OR= 1.03 (0.95-
    1.10)
    5-day mean, IQR= 22, OR= 1.05 (0.97-
    1.13)
    14-day mean, IQR= 17, OR= 1.03
    (0.96-1.10)
    Reference: von Klot et al. (2002,
    0347061
    Period of Study: Sep 1996-Mar 1997
    (winter)
    Location: Erfurt, Germany
     Outcome: Asthma symptoms
     (wheezing, shortness of breath at rest,
     waking up with breathing problems, or
     coughing without having a cold) and
     Asthma medication (inhaled short-acting
     B2- agonists, inhaled long-acting B2-
     agonists, inhaled corticosteroids,
     cromolyn sodium, theophylline, oral
     corticosteroids, and N-acetylcysteine)
     Age Groups: Adults, mean=59.0 yr and
     range =37-77 yr
     Study Design: Panel study
     N: 53 adult asthmatics
     Statistical Analyses: Logistic
     regression models
     Covariates: Seasonal variation in
     medication use or symptom prevalence,
     meteorological factors (relative humidity,
     temperature), weekend,  Christmas
     holidays
     Season: Winter
     Dose-response Investigated? No
     Statistical Package: NR
     Lags Considered:0,1,2,3,4,5,6,7,
     8, 9,10, ma calculated from same day
     and preceding days
     Pollutant: PMi0.2.5
     Averaging Time: 24 h
     Mean (SD): 10.3
     Percentiles:
     25th: 2.9
     SOth(Median): 6.9
     75th: 14.6
     Range (Min, Max): (-8.7-64.3)
     Copollutant (correlation):
     NC0.i-0.oi:r=0.41
     NC0.5-o.i: r=0.50
     NC25.05: r= 0.48
     MCo.5-o.i:r=0.51
     MC2.5.o.oi:r=0.52
     PM10:r=0.67
     N02: r= 0.45
     CO: r= 0.42
     S02: r= 0.28
    PM Increment: 1 IQR
    Effect Estimate [Lower Cl, Upper Cl]:
    Association between the prevalence of
    inhaled B2- agonist use and PM10.25
    Same day, IQR= 12, OR= 1.01 (0.95-
    1.06)
    5-day mean, IQR= 11, OR= 1.01 (0.94-
    1.09)
    14-day mean,  IQR= 6.7, OR= 0.92
    (0.86-1.00)
    Association between the prevalence of
    inhaled corticosteroid use and PMi0.25
    Same day, IQR= 12, OR= 1.03 (0.98-
    1.08)
    5-day mean, IQR= 11, OR= 1.12 (1.04-
    1.20)
    14-day mean,  IQR= 6.7, OR= 1.27
    (1.18-1.37)
    Association between the prevalence of
    wheezing and  PMi0.2.5
    Same day, IQR= 12, OR= 0.97 (0.91-
    1.02)
    5-day mean, IQR= 11, OR= 1.06 (0.98-
    1.15)
    14-day mean,  IQR= 6.7, OR= 1.05
    (0.96-1.15)
    Reference: Ward et al. (2002, 0258391
    Period of Study: 1997 (two 8-wk
    periods)
    Location: Birmingham and Sandwell,
    UK
    Outcome: Change in PEF (peak
    expiratory flow), self reported
    respiratory symptoms (same day
    cough, illness, short of breath, waking
    up at night with cough or wheeze,
    wheeze)
    Age Groups: 9 yr olds
    Study Design:
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD):
    Wnter:12.7|jg/m3
    Summer: 12.3 pg/m3
    Range (Min, Max):
    PM Increment:
    Wnter: 12.3 pg/m3
    Summer: 6.3 pg/m3
    Mean (PEF l/min) [Lower Cl, Upper Cl]
    lag:
    Winter morning:
    0.80 [-1.97, 3.67] lag 0
    0.62 [-2.22, 3.54] lag 1	
    December 2009
                                    E-224
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                       Time-series Panel study
    
                                       N: 162 children from 5 schools
    
                                       Statistical Analyses: Linear regression
                                       (PEF),
    
                                       Logistic regression (respiratory
                                       symptoms)
    
                                       Covariates: Trend,  temperature,
                                       schooldays (yes/no)
    
                                       Season: Winter (Jan 13-Mar 10)
    
                                       Summer (May 19-Jul 14)
    
                                       Dose-response Investigated? No
    
                                       Statistical Package: Nr
    
                                       Lags Considered:  Lag 0, lag 1, lag 2,
                                       lag 3, 7-day ma
                                Winter: 4, 37
    
                                Summer: 5, 28
    
                                PM Component:
    
                                Total mass
    
                                Monitoring Stations:
    
                                5 stations near the 5 schools
    
                                Copollutant (correlation):
    
                                Wnter:
    
                                PM10(r=0.93)
    
                                N02 (F0.88)
    
                                03 (p-0.83)
    
                                Summer:
    
                                HN03(r=0.81)
                               -0.86
                               -2.47
                               -4.07
      -4.32, 2.47] lag 2
      -5.30, 0.36] lag 3
      -10.60, 2.42] 7-day mean
                               Winter afternoon:
                               0.95 [-2.22, 4.23] lag 0
                               -0.99 [-4.69, 2.72] lag 1
                               -1.60 [-5.18, 2.01] lag 2
                               -3.45 [-6.53 to-0.25] lag 3
                               1.00 [-11.47,13.56] 7-day mean
    
                               Summer morning:
                               -1.49 [-3.65, 0.67] lag 0
                               0.21
                               2.50
                               3.41
                               3.90
     -2.12, 2.55] lag 1
     0.28, 4.72] lag 2
     1.40, 5.44] lag 3
     -2.53,10.33] 7-day mean
                               Summer afternoon:
                               -0.49 [-2.43, 1.45
                               -0.78 [-2.72, 1.16
                lagO
                Iag1
                               0.57 [-1.35, 2.49] lag 2
                               0.16 [-1.85, 2.17] lag 3
                               -0.08 [-5.43, 5.27] 7-day mean
    
                               Winter morning in atopy/recent
                               wheezing subgroup:
                                                                                                               -0.072
                                                                                                               -0.271
                                                                          -0.527, 0.383
                                                  lagO
                                                  Iag1
                                                                                                                     -0.701,0.159
                                                                                                               0.127[-0.354, 0.608]"lag'2
                                                                                                               0.055 [-0.391, 0.501] lag 3
    
                                                                                                               Winter morning in no atopy or recent
                                                                                                               wheezing subgroup:
                                                                                                               0.126 [-0.413, 0.666] lag0
                                                                                                               0.193 [-0.340, 0.728] lag 1
                                                                                                               -0.170
                                                                                                               -0.314
                                                                          -0.788, 0.447
                                                                          -0.846,0.216
                                                   lag 2
                                                   Iag3
                                                                                                               Winter morning in subgroup with
                                                                                                               parental atopy/recent wheezing:
                                                                                                               0.187 [-0.008, 0.382] lag0
                                                                                                               -0.006 [-0.207, 0.195] lag 1
                                                                                                               -0.011  [-0.226, 0.204] lag 2
                                                                                                               -0.037 [-0.228, 0.154] lag3
    
                                                                                                               Winter morning in subgroup without
                                                                                                               parental atopy/recent wheezing:
                                                                                                               0.026 [-0.341 , 0.395] lag 0
                                                                                                               0.068 [-0.307 , 0.444] lag 1
    -0.099 -0.535 , 0.335] lag 2
    -0.252 -0.61 5, 0.1 10] lag 3
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Cough:
    Winter: 0.98 [0.80, 1.1 8] lag 0
    0.95
    1.02
    1.01
    1.31
    0.77, 1.17
    0.83, 1.24
    0.83, 1.23
    0.82, 2.09
    Summer: 1.13
    1.04
    0.94
    0.89
    0.81
    0.94, 1.13
    0.87, 1.02
    0.82, 0.96
    0.62, 1.06
    Iag1
    lag 2
    Iag3
    7-day mean
    1.04, 1.22] lag 0
    Iag1
    lag 2
    lagS
    7 day mean
    Illness:
    Winter: 1.17 [1.05, 1.32] lag 0
    1.07
    1.16
    1.01
    1.57
    0.95, 1.23
    1.01, 1.35
    0.90, 1.16
    1.15,2.13
    Iag1
    lag 2
    lagS
    7-day mean
    Summer: 1.02 [0.91, 1.13] lag 0
    1.00
    0.96
    0.97
    0.68
    0.89, 1.13
    0.85, 1.07
    Iag1
    lag 2
    0.86, 1.09] lag 3
    0.41, 1.1 3] 7-day mean
    December 2009
                             E-225
    

    -------
    Study
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Ward et al. (2002, 0258391
    Period of Study: 1997 (two 8-wk
    periods)
    Location: Birmingham and Sandwell,
    UK
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Change in PEF (peak
    expiratory flow), self reported
    respiratory symptoms (same day
    cough, illness, short of breath, waking
    up at night with cough or wheeze,
    wheeze)
    Age Groups: 9 yr olds
    Study Design:
    Time-series panel study
    
    N: 162 children from 5 schools
    Statistical Analyses: Linear regression
    (PEF),
    Logistic regression (respiratory
    symptoms)
    Covariates: Trend, temperature,
    schooldays (yes/no)
    Season: Winter (Jan 13-Mar 10)
    Summer (May 19- Jul 14)
    
    Concentrations1
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: Sulfate
    Averaging Time: 24 h
    Mean (SD):
    Wnter: 2.4 pg/m3
    Summer: 3.8 pg/m3
    Range (Min, Max):
    Wnter: 0.8, 14.9
    
    Summer: 1.1, 7.8
    PM Component:
    
    S04
    Monitoring Stations: 2 stations
    
    
    
    
    
    Effect Estimates (95% Cl)
    Shortness of breath:
    Winter: 1.07 [0.94, 1.24] lag 0
    0.98 0.84, 1.13] lag 1
    0.96 0.82, 1.13]lag2
    0.91 0.79, 1.07] lag 3
    0.82 0.58, 1.1 8] 7-day mean
    Summer: 1.04 [0.90, 1.20] lag 0
    1.08 0.93, 1.25] lag 1
    0.97 0.84, 1.13] lag 2
    0.93 0.81, 1.08] lag 3
    1.16 0.76, 1.77] 7-day mean
    Wake at night with cough/wheeze:
    Winter: 1.10 [0.96, 1.26] lag 0
    1.05 0.90, 1.22 Iag1
    0.98 0.83, 1.13; lag 2
    0.94 0.81, 1.09; lag 3
    0.93 0.66, 1.32 7-day mean
    Summer: 0.93 0.78, 1.10]lagO
    0.81 0.67, 0.98 lag 1
    0.91 0.77,1.09 lag 2
    0.97 0.83, 1.13 Iag3
    1.04 0.57, 1.90 7-day mean
    Wheeze:
    Winter: 0.98 [0.83, 1.1 6] lag 0
    0.90 0.75, 1.05] lag 1
    1.00 0.83, 1.20] lag 2
    1.13 0.95, 1.35] lag 3
    1.02 0.68, 1.57]; 7-day mean
    Summer: 1.02 [0.88, 1.19]lagO
    0.98 0.84, 1.16] lag 1
    0.87 0.74, 1.02] lag 2
    0.85 0.72, 0.99] lag 3
    0.96 0.51, 1.81] 7-day mean
    PM Increment:
    Wnter: 4.8 pg/m3
    Summer: 3.1 pg/m3
    Mean (PEF l/min) [Lower Cl, Upper Cl]
    lag
    Winter morning:
    -1.75 -4.00, 0.50] lag 0
    -0.91 -3.44, 1.62] lag 1
    -0.62 -3.16, 1.91] lag 2
    -1.82 -4.27, 0.64] lag 3
    -3.22 -8.03, 1.58] 7-day mean
    Winter afternoon:
    0.99 [-1.58, 3.55] lag 0
    0.79 [-2.42, 4.00] lag 1
    -1.89 [-4.99, 1.21] lag 2
    -1.73 [-4.69, 1.23] lag 3
    -1.96 [-13.35, 9.42] 7-day mean
    Summer morning:
    -0.72 [-3.27, 1.82] lag 0
    -1. 69 [-4.28, 0.90] lag 1
    1.35 -1.27, 3.97] lag 2
    3.38 1.03, 5.72] lag 3
                                       Statistical Package: Nr
    
                                       Lags Considered: Lag 0, lag 1, lag 2,
                                       lag 3, 7-day ma
                                           2.98 [-4.17,10.13] 7-day mean
    
                                           Summer afternoon:
                                           -0.32 [-2.81, 2.17] lag 0
                                           0.84 [-1.63,  3.30] lag 1
                                           -0.08 [-2.61, 2.44] lag 2
                                            -0.25 [-2.69, 2.19]lag3
                                           -2.20 [-9.51, 5.12] 7-day mean
    
                                           Winter morning in atopy/recent
                                           wheezing subgroup:
                                           0.200 [-0.755, 1.156] lag 0
                                                                                                              -0.219
                                                                                                              -0.431
                                                  -1.318,0.881
                                                  -1.526,0.664
    Iag1
    ;lag2
                                                                                                               1.200 [0.095, 2.305] lag 3
    December 2009
    E-226
    

    -------
                 Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                           Winter morning in no atopy or recent
                                                                                                           wheezing subgroup:
                                                                                                           -0.613 [-1.714, 0.488] lag 0
                                                                                                           -0.174 [-1.423, 1.075] lag 1
                                                                                                           0.006 [-1.243, 1.253] lag 2
                                                                                                           -1.080 [-2.308, 0.148] lag 3
    
                                                                                                           Winter morning in subgroup with
                                                                                                           parental atopy/recent wheezing:
                                                                                                           0.457 [0.003, 0.910] lag0
                                                                                                           0.078 [-0.503, 0.660] lag 1
                                                                                                           -0.102[-0.656, 0.452] lag 2
                                                                                                           0.002 [-0.609, 0.613] lag 3
    
                                                                                                           Winter morning in subgroup without
                                                                                                           parental atopy/recent wheezing:
    -0.622 -1.379, 0.1 36] lag 0
    -0.272 -1.147, 0.602] lag 1
    -0.138 -1.005, 0.728] lag 2
    -0.496 -1.359, 0.367] lag 3
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Cough:
    Winter: 1.01 [0.84, 1.20] lag 0
    1.02
    0.99
    0.86
    0.78
    0.85, 1.24
    0.82, 1.20
    0.71, 1.05
    0.53, 1.14
    Summer: 1.08
    1.03
    0.97
    0.90
    0.73
    0.93, 1.15
    0.88, 1.07
    0.82, 0.99
    0.54, 0.97
    Iag1
    lag 2
    Iag3
    7-day mean
    0.98, 1.20] lag 0
    Iag1
    lag 2
    Iag3
    7 day mean
    Illness:
    Winter: 1.06 [0.96, 1.1 7] lag 0
    1.15
    1.14
    1.04
    1.30
    1.03, 1.28
    1.00, 1.28
    0.92, 1.18
    1.00, 1.66
    Iag1
    lag 2
    lagS
    7-day mean
    Summer: 0.98 [0.86 1.11]lagO
    0.97
    1.01
    0.95
    0.72
    0.84, 1.12
    0.88, 1.16
    0.84, 1.09
    0.46, 1.12
    Iag1
    lag 2
    lagS
    7-day mean
    Shortness of breath:
    Winter: 0.96 [0.85, 1.07] lag 0
    0.98
    0.94
    0.93
    0.80
    0.86, 1.12
    0.82, 1.07
    0.81, 1.08
    0.59, 1.07
    Iag1
    Iag2
    lagS
    7-day mean
    Summer: 0.95 [0.80, 1.14]lagO
    1. 07 [0.89, 1.28] lag 1
    1.04
    0.94
    0.87, 1.24
    0.80, 1.12
    lag 2
    lagS
    |0.58[0.33, 1.04] 7-day mean
    Wake at night with cough/wheeze:
    Winter: 0.97 [0.87, 1.08] lag 0
    1.01
    1.00
    0.93
    0.79
    0.89, 1.15
    0.88, 1.14
    0.82, 1.07
    0.59, 1.05
    Summer: 0.95
    0.81
    0.93
    0.87
    0.77
    0.67, 0.99
    0.76, 1.13
    0.72, 1.05
    0.41, 1.48
    Iag1
    ;lag2
    ;lag3
    7-day mean
    0.78, 1.16] lag 0
    Iag1
    lag 2
    lagS
    7-day mean
    Wheeze:
    Winter: 1.00 [0.87, 1.1 5] lag 0
    0.96 [0.82, 1.13]lag1
    0.88
    1.12
    0.75, 1.04
    0.95, 1.32
    lag 2
    lagS
    December 2009
                            E-227
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                                                               0.83 [0.58,1.20]; 7-day mean
    
                                                                                                               Summer: 0.97 [0.80,1.17]lagO
                                                                                                               .09 [0.89, 1.32] lag 1
                                                                                                               1.00 [0.82, 1.22] lag 2
                                                                                                               0.81
                                                                                                               1.30
                                                                                0.69, 0.97
                                                                                0.68, 2.50
                                                      Iag3
                                                      7-day mean
    Reference: Ward et al. (2002, 0258391
    
    Period of Study: 1997 (two 8-week
    periods)
    
    Location: Birmingham and Sandwell,
    UK
    Outcome: Change in PEF (peak
    expiratory flow), self reported
    respiratory symptoms (same day
    cough, illness, short of breath, waking
    up at night with cough or wheeze,
    wheeze)
    
    Age Groups: 9 yr olds
    
    Study Design: Time-series panel study
    
    N: 162 children from 5 schools
    
    Statistical Analyses: Linear regression
    (PEF),
    
    Logistic regression (respiratory
    symptoms)
    
    Covariates: Trend, temperature,
    schooldays (yes/no)
    
    Season: Winter (Jan 13-Mar 10)
    
    Summer (May 19-Jul 14)
    
    Dose-response  Investigated? No
    
    Statistical Package: Nr
    
    Lags Considered: Lag 0, lag 1, lag 2,
    lag 3,  7-day ma
    Pollutant: N03
    
    Averaging Time: 24 h
    
    Mean (SD):
    
    Wnter: 3.6 pg/m3
    
    Summer: 3.5 pg/m3
    
    Range (Min, Max):
    
    Wnter: 0.1, 29.9
    
    Summer: 0.7,13.2
    
    Monitoring Stations: 2 stations
    PM Increment: Wnter: 6.7 pg/m3
    
    Summer: 3.7 pg/m3
    
    Mean (PEF l/min) [Lower Cl, Upper Cl]
    lag:
    
    Winter morning:
    -2.08 [-4.02 to-0.15] lagO
    -0.64 [-2.87, 1.59] lag 1
    0.71 [-1.69, 3.11] lag 2
    -1.38 [-3.61, 0.84] lag 3
    -0.92 [-5.32, 3.47] 7-day mean
    
    Winter afternoon:
    0.24 [-1.89, 2.38] lagO
    -0.72 [-3.87, 2.43] lag 1
    -1.37 [-5.11, 2.38] lag 2
    -2.54 [-5.74, 0.66] lag 3
    0.21 [-7.67, 8.11] 7-day mean
    
    Summer morning:
    -0.80 [-2.74, 1.15] lag 0
                                                                                                               0.68
                                                                                                               1.42
                                                                                                               2.54
                                                                                                               1.74
                                             -1.31, 2.67]Iag1
                                             -0.73, 3.58] Iag2
                                             0.48, 4.59] Iag3
                                             -2.66, 6.13] 7-day mean
                                                                                                               Summer afternoon:
                                                                                                               -0.72 [-2.47, 1.03
                                                                                                               -0.59 [-2.36, 1.18
                                                        lagO
                                                        Iag1
                                                                                                               -0.33 [-2.11, 1.45] lag 2
                                                                                                               0.66 [-1.26, 2.58] lag 3
                                                                                                               0.47 [-3.36, 4.29] 7-day mean
    
                                                                                                               Winter morning in atopy/recent
                                                                                                               wheezing subgroup:
                                                                                                               -0.036 [-0.627 , 0.555] lag 0
                                                                                                               0.142 [-0.573, 0.857] lag 1
                                                                                                               0.000 [-0.760, 0.759] lag 2
                                                                                                               0.689 [-0.061, 1.439] lag 3
    
                                                                                                               Winter morning in no atopy or recent
                                                                                                               wheezing subgroup:
                                                                                                               -0.434 [-1.116, 0.248] lag 0
                                                                                                               -0.201 [-1.002, 0.600] lag 1
                                                                                                               0.154 [-0.703, 1.010] lag 2
                                                                                                               -0.605 [-1.422, 0.210] lag 3
    
                                                                                                               Winter morning in subgroup with
                                                                                                               parental atopy/recent wheezing:
                                                                                                               0.228
                                                                                                               0.476
                                                                                                               0.196
                                                                                                               0.083
                                                                                 -0.054, 0.511] lag 0
                                                                                 0.060, 0.892] lag 1
                                                                                 -0.202, 0.594] lag 2
                                                                                 -0.321, 0.487] lag 3
                                                                                                               Winter morning in subgroup without
                                                                                                               parental atopy/recent wheezing:
                                                                                                               -0.482 [-0.952,-0.012] lag 0
                                                                                                               -0.276 [-0.846, 0.294] lag 1
                                                                                                               0.078 [-0.520, 0.675] lag 2
                                                                                                               -0.298 [-0.864, 0.268] lag 3
    
                                                                                                               RR Estimate [Lower Cl, Upper Cl]
                                                                                                               Cough: Winter:
    0.92
    0.91
    0.99
    0.87
    0.71
    0.80, 1.07
    0.77, 1.07
    0.83, 1.17
    0.73, 1.03
    0.52, 0.97
    lagO
    Iag1
    lag 2
    Iag3
    7-day mean
    Summer: 1.05 [0.97, 1.13]lagO
    December 2009
                                    E-228
    

    -------
                 Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                          1.01 [0.93,1.10] lag 1
                                                                                                          0.95 [0.88, 1.03] lag 2
                                                                                                          0.89 [0.83, 0.96] lag 3
                                                                                                          0.81 [0.68, 0.97] 7 day mean
    
                                                                                                          Illness: Winter: 1.05 [0.97,1.14] lag 0
    1.11
    1.13
    1.13
    1.13
    1.01,1.22
    1.01, 1.26
    1.04, 1.26
    0.92, 1.38
    Iag1
    lag 2
    Iag3
    7-day mean
    Summer: 0.97 [0.87, 1.09] lag 0
    0.98
    0.95
    0.94
    0.74
    0.87, 1.10
    0.85, 1.06
    0.85, 1.05
    0.54, 1.03
    Iag1
    lag 2
    Iag3
    7-day mean
    Shortness of breath: Winter:
    0.99
    1.01
    0.93
    0.98
    0.85
    0.90, 1.10
    0.90, 1.13
    0.82, 1.05
    0.86, 1.13
    0.67, 1.08
    Summer: 1.04
    1.12
    1.04
    0.90
    1.06
    0.98, 1.28
    0.90, 1.20
    0.79, 1.03
    0.78, 1.43
    lagO
    Iag1
    Iag2
    lags
    7-day mean
    0.90, 1.18] lag 0
    Iag1
    lag 2
    lagS
    7-day mean
                                                                                                          Wake at night with cough/wheeze:
                                                                                                          Winter:
    0.98
    1.05
    0.99
    0.99
    0.84
    0.89, 1.08
    0.94, 1.16
    0.88, 1.12
    0.87, 1.12
    0.67, 1.05
    lagO
    Iag1
    ;lag2
    ;lag3
    7-day mean
    Summer: 0.94 [0.80, 1.09] lag 0
    0.86
    0.94
    0.92
    0.95
    0.72, 1.01
    0.79, 1.11
    0.79, 1.07
    0.62, 1.47
    Iag1
    lag 2
    lagS
    7-day mean
                                                                                                          Wheeze: Winter: 0.98 [0.87,1.10] lag 0
    1.00
    0.89
    1.11
    0.80
    0.87, 1.14
    0.77, 1.03
    0.95, 1.30
    0.61, 1.07
    Summer: 1.01
    0.96
    0.95
    0.87
    1.04
    0.83, 1.11
    0.82, 1.10
    0.75, 1.01
    0.67, 1.60
    Iag1
    lag 2
    lagS
    7-day mean
    0.87, 1.17] lag 0
    Iag1
    lag 2
    lagS
    7-day mean
    All units expressed in pg/m  unless otherwise specified.
    December 2009
                            E-229
    

    -------
    E.2.2. Respiratory Emergency Department Visits and Hospital Admissions
    Table E-12. Short-term
    Reference
    Reference: Andersen et al. (2008,
    1896511
    
    1st page: 458
    
    Period of Study: May 2001- Dec 2004
    Location: Copenhagen, Denmark
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Cheng et al. (2007,
    0930341
    
    Period of Study: 1996-2004
    
    Location: Kaohsiung, Taiwan
    
    
    
    
    
    
    
    
    
    
    exposure-respiratory-ED/HA-PMi .
    Design & Methods
    Hospital Admissions/ED visits
    
    Outcome (ICD-10):
    
    RD, including chronic bronchitis
    (J41-42), emphysema (J43), other
    chronic obstructive pulmonary disease
    (J44), asthma (J45), and status
    asthmaticus (J46).
    Pediatric hospital admissions for
    asthma (J45) and status asthmaticus
    / \AR\
    (JtO).
    Age Groups Analyzed: >65 yr (RD
    combined), 5-1 Syr (asthma)
    Study Design: Time series
    N: NR
    Statistical Analyses: Poisson GAM
    Covariates: temperature, dew-point
    temperature, long-term trend,
    seasonality, influenza, day of the week,
    public holidays, school holidays (only
    for 5-18 yr olds), pollen (only for
    pediatric asthma outcome)
    Season: NR
    
    Dose-response Investigated: No
    Statistical package: R statistical
    software (gam procedure, mgcv
    package)
    Lags Considered: Lag 0 -5 days,
    5-day avg (lag 0-4) for RD, and a 6-day
    avg (lag 0-5) for asthma.
    Outcome (ICD-9: 480-486):
    Pneumonia
    
    Age Groups: NR
    
    Study Design: Case-crossover
    
    N: 82,587 pneumonia hospital
    admissions
    
    Statistical Analyses: Conditional
    logistic regression
    Covariates: Temperature and humidity
    on the same day
    Season: NR
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: Cumulative lag
    period up to 2 previous days
    
    Concentrations1
    Pollutant: PM,0 (pg/m3)
    
    Averaging Time: 24 h
    
    Mean(SD): 24(14)
    
    Median: 21
    IQR: 16-29
    99th percentile: 72
    Monitoring Stations: 1
    Copollutant (correlation):
    NCtot:r = 0.39
    NC100:r = 0.28
    NCa12:r = 0.02
    Nca23:r = -0.12
    NCa57:r = 0.45
    Nca212:r = 0.63
    PM25:r = 0.80
    CO: r = 0.37
    N02: r = 0.35
    :r = 0.32
    curbside:r = 0.18
    03:r = -0.21
    Other variables:
    Temperature: r = 0.12
    Relative humidity: r = 0.05
    
    
    
    
    
    
    
    
    Pollutant: PM10
    
    Averaging Time: 24 h
    
    Mean (min-max):
    
    77.01 (16.7-232)
    Percentiles: 25%: 42.12
    
    50%: 75.27
    75%: 104.65
    Monitoring Stations: 6
    Copollutant: NR
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 13 pg/m3 3 (IQR)
    
    Relative risk (RR) Estimate [Cl]:
    
    RD hospital admissions (6 day avg,
    lag 0 -4), age 66+: One-pollutant
    model: 1.06 [1.02-1. 09]
    Adj for NCtot: 1.05 [1.01-1. 10]
    Adj for NCa212: 1.04 [0.98-1. 11]
    Asthma hospital admissions (6-day
    avg lag 0-6), age 6 - 18: One-pollutant
    model: 1.02 [0.93-1. 12]
    Adj for NCtot: 1.01 [0.91-1.12]
    Adj for NCa212: 0.94 [0.81-1.09]
    Estimates for individual day lags
    reported only in Fig form (see notes):
    Notes: Fig 2: Relative risks and 95%
    confidence intervals per IQR in single
    day concentration (0-5 day lag).
    Summary of Fig 2: RD: Positive,
    statistically or marginally significant
    associations at Lag 2-5. Asthma: Wide
    confidence intervals make interpretation
    difficult. Positive associations at Lag 1,
    2, 3, and 5.
    
    
    
    
    
    
    PM Increment: 62.53 pg/m3 (IQR)
    
    OR Estimate [Cl]: Single Pollutant
    Model: Temp>25(1C: 1.21 [1.15,1.28]
    
    Temp <25°C: 1.57 [1.50,1. 65]
    
    Two-Pollutant Model: Temp>25°C
    Adj. for S02: 1.21 [1.14,1.28]
    Adj. for N02: 1.15 [1.07,1. 24]
    Adj. for CO: 1.10 [1.03, 1.1 7]
    Adj. for 03: 0.96 [0.89,1. 03]
    Temp < 25°C
    Adj. for S02: 1.56 [1.48,1.65]
    Adj. for N02: 1.09 [1.02,1. 16]
    Adj. for CO: 1.30 [1.22, 1.39]
    Adj. for 03: 1.56 [1.48,1. 65]
    December 2009
    E-230
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chimonas and Gessner
    (2007, 0932611
    
    Period of Study: Jan 1999-Jun 2003
    
    Location: Anchorage, Alaska
    Outcome (ICD-9): Asthma (493.0-
    493.9); Lower respiratory illness-LRI
    (466.1,466.0,480-487,490,510-511);
    Inhaled quick-relief medication; Steroid
    medication
    
    Age Groups: <20 yr old
    
    Study Design: Time series
    
    N: 42,667 admissions
    
    Statistical Analyses: GEE for
    multivariable modeling
    
    Covariates: Season, serial correlation,
    yr, weekend,  temperature, precipitation,
    and wind speed
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: SPSS (dataset),
    SAS (analysis)
    
    Lags Considered: 1 day and 1 week
    Pollutant: PM,0
    
    Averaging Time: 24 h and 1 wk
    
    Mean (min-max):
    
    Daily: 27.6 (2-421)
    
    Weekly: 25.3 (5.0-116.0)
    
    Monitoring Stations: NR
    
    Copollutant: Daily PM25
    
    p = 0.25 (p< 0.01)
    
    Weekly PM25
    
    p = 0.08 (p = 0.21)
    PM Increment: 10 pg/m
    
    RR Estimate [Cl]:
    Same Day
    Outpatient Asthma: 1.006 [1.001,1.013]
    Outpatient LRI: 1.001 [0.987,1.015]
    Inpatient Asthma: 1.003 [0.922,1.091]
    Inpatient LRI: 1.015 [0.978,1.053]
    Inhaled Steroid Prescriptions:
    1.006 [0.996,1.011]
    Quick-relief Medication:
    1.018 [1.006,1.030]
    Weekly (median increase)
    Outpatient Asthma: 1.021 [1.004,1.038]
    Outpatient LRI: 1.013 [0.978,1.049]
    Inpatient Asthma: 1.023 [0.948,1.104]
    Inpatient LRI: 1.025 [0.981,1.072]
    Inhaled Steroid Prescriptions:
    0.989 [0.969,1.010]
    Quick-relief Medication:
    1.057 [1.037,1.077]
    Reference: Chiu et al. (2008,1919891
    
    Period of Study: 1996-2001
    
    Location: Taipei, Taiwan
    Outcome: Hospital admissions for
    COPD
    
    Study Design: Time-series
    
    Covariates: Temperature, humidity,
    PM10and03
    
    Statistical Analysis: Poisson
    regression
    
    Statistical Package: SAS
    
    Age Groups: All
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD) Unit:
    
    Index Days: 111.68 + 38.32 pg/m3
    
    Comparison Days: 55.43 + 24.66 pg/m3
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    All results refer to "dust storm days" and
    can be found in Table 3
    Reference: Chiu et al. (2009,1902491
    
    Period of Study: 1996-2004
    
    Location: Taipei, Taiwan
    Outcome: Hospital admissions for
    pneumonia (ICD-9 480-486)
    
    Study Design: Time-series
    
    Covariates: Weather variables, day of
    the week, seasonality,  long-term time
    trends
    
    Statistical Analysis: Conditional
    logistic regression
    
    Statistical Package: SAS
    
    Age Groups: All
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean Unit: 49.47 pg/m3
    
    Range (Min, Max): 14.42, 234.91
    
    Copollutant (correlation):
    
    S02: 0.50
    
    N02: 0.58
    
    CO: 0.34
    
    03: 0.31
    Increment: IQR
    
    Odds Ratio (96% Cl)
    
    Temperatures 23° C:
    Temperature < 23° C:
    
    Adjusted for S02
    
    Temperatures 23° C:
    Temperature < 23° C:
    
    Adjusted for N02
    
    Temperatures 23° C:
    Temperature < 23° C:
    
    Adjusted for CO
    
    Temperatures 23° C:
    Temperature < 23° C:
    
    Adjusted for 03
    
    Temperatures 23° C:
    Temperature < 23° C:
    1.11 (1.08-1.14)
    1.09(1.07-1.11)
                                                                                                                                  1.10(1.08-1.13)
                                                                                                                                  1.19(1.17-1.22)
                                                                                                                                  0.90 (0.88-0.93)
                                                                                                                                  1.09(1.07-1.12)
                                                                                                                                  1.03(1.00-1.05)
                                                                                                                                  1.07(1.05-1.10)
                                                                                                                                  1.05(1.03-1.08)
                                                                                                                                  1.09(1.07-1.11)
    December 2009
                                    E-231
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Erbas et al. (2005, 0738491  Hospital Admissions
    Period of Study: Jan 2000-Dec 2001
    
    Location: Melbourne, Australia
    Outcome (ICD-10): Asthma (J45, J46)
    
    Age Groups: 1-1 Syr
    
    Study Design: Time series
    
    N: 8955 asthma cases
    
    Statistical Analyses: GAM, GEE (if
    autocorrelation was present in
    residuals)
    
    Covariates: Temp and humidity
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 0, 1, 2 days
    Pollutant: PM,0
    
    Averaging Time: 1 h
    Mean (SD):
    Western: 2.99 (2.11)
    10th percentile: 13.67
    90th percentile: 48.00
    Inner Melbourne: 4.54 (2.65)
    10th percentile: 15.63
    90th percentile: 59.73
    South/Southeastern: 1.13 (1.18)
    10th percentile: 12.00
    90th percentile: 36.05
    Eastern: 3.61 (2.39)
    10th percentile: 16.00
    90th percentile: 51.05
    Combined: 30.07 (10.55-112.33)
    SD= 15.27
    10th percentile: 16.00
    90th percentile: 50.51
    Monitoring Stations:  Data obtained
    from an air quality simulation model
    (TAPM) by CSIRO Atmospheric
    Research
    
    Copollutant: NR
    PM Increment: Increase from 10th to
    90th percentile
    
    RR Estimate [Cl]:
    
    Same day lag
    
    Western: NR
    
    Inner Melbourne:  1.17 [1.05,1.31]
    
    South/Southeastern: 1.14 [0.95,1.33]
    
    Eastern: 1.09 [1.01,1.18]
    
    Notes: All other lags NR
    Reference: Farhat et al. (2005,
    0894611
    
    Period of Study: Aug 1996-Aug 1997
    
    Location: Sao Paulo,  Brazil
    Hospital Admissions and Emergency
    Room Visits
    
    Outcome (ICD-9): Lower respiratory
    tract diseases (466, 480-519) including
    pneumonia or bronchopneumonia (480-
    486), asthma (493), bronchiolitis (466)
    
    Age Groups:  <13yr
    
    Study Design: Time series
    
    N: 43,635
    
    Statistical Analyses: GAM, Poisson
    regression, Pearson correlation
    
    Covariates: Time, temperature,
    humidity, weekday
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: S-Plus
    
    Lags Considered: 0-7 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Mean (min-max):
    62.6(25.5-186.3)
    SD = 26.6
    IQr = 30
    N = 396
    
    Monitoring Stations: 13
    
    Copollutant (correlation): S02:
    r = 0.69
    N02:r = 0.83
    03:r = 0.35
    CO: r  = 0.72
    (all p < 0.05)
    
    Additional correlations:
    Rel humidity: r = -0.55
    Mintemp: r = -0.44
    (both p< 0.05)
    PM Increment: 30 pg/m (IQR)
    
    RR Estimate [Cl]:
    Lower respiratory tract disease
    5-day ma
    Copollutant model:
    N02: 2.1 [-7.1,11.3]
    S02:16.5 [10.5,22.6]
    03: 10.1 [5.0,15.2]
    CO: 14.1 [8.1,20.2]
    Multipollutant model: 5.2 [-4.6,15.1]
    Pneumonia or bronchopneumonia
    6-day ma
    Copollutant model:
    N02:14.8 [-3.8,33.4]
    S02:14.8 [-0.3,30.0]; 03:16.2 [1.0,31.3]
    CO: 17.6 [0.4,34.8]
    Multipollutant model: 5.23 [-16.2,26.6]
    Asthma or bronchiolitis
    2-day ma
    Copollutant model:
    N02:-11.04 [-50.0,28.0]
    S02:15.8 [-7.8,39.3]
    03: 11.7 [-10.4, 33.9]
    CO: 12.4 [-14.8,39.7]
    Multipollutant model: -15.5 [-61.2,30.2]
    December 2009
                                    E-232
    

    -------
    Reference
    Reference: Fung et al. (2006, 0897891
    Period of Study: June 1995-Mar 99
    Location: Vancouver, Canada
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Fung al. (2005, 0932621
    Period of Study: Nov 1995-Dec 2000
    Location: London, Ontario
    
    
    
    
    
    
    
    
    
    Design & Methods
    Hospital Admission/ED
    Outcome: Respiratory diseases (460-
    519)
    Age Groups: Age >65
    Study Design: Time series
    N: 26,275 individuals admitted
    
    Statistical Analyses: Poisson
    regression (spline 12 knots), case-
    crossover (controls +17 days from case
    date), Dewanji and Moolgavkar (DM)
    method
    Covariates: Long-term trends, day-of-
    the-week effect, weather
    Season: All yr
    Dose-response Investigated? No
    
    Statistical Package: SPIus, R
    Lags Considered: 0-7 days
    
    
    
    
    
    
    
    
    
    Hospital Admissions
    Outcome (ICD-9): Asthma (493) and all
    other respiratory diseases (460-519)
    Age Groups: <65 yr
    65+ yr
    Study Design: Time series
    N: 5574 respiratory admissions
    Statistical Analyses: GAM with locally
    weighted regression smoothers
    (LOESS)
    Covariates: Maximum and minimum
    temp, humidity, day of the week,
    seasonal cycles, secular trends
    Qeacniv MP
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD): 13.31(6.13) pg/m3
    Range (Min, Max): (3.77, 52.17)
    Monitoring Stations: NR
    
    Copollutant (correlation): PIvl-;
    PM25 r = 0.80
    P M r - n 11
    r lvlio-2.5 1 - -U. II
    CO r = 0.46
    Coh r = 0.61
    03 r = -0.08
    
    N02r = 0.54
    S02r = 0.61
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (min-max):
    38.0 (5-248)
    SD = 23.5
    Monitoring Stations: 4
    Copollutant (correlation):
    N02:r = 0.30
    S02: r = 0.24
    CO: r = 0.21
    0 • r = o 53
    
    COH: r = 0.29
    Effect Estimates (95% Cl)
    PM Increment: : 7.9 pg/m3
    Rr Estimate (65+ Yr)
    Dm Method:
    1.014(0.998,1.029]
    I -an 0
    Lag u
    1.016[0.998,1.034]
    
    3-day avg
    0.988(0.970, 1.006]
    5-day avg
    0.983[0.963, 1.004]
    7-day avg Time Series:
    1.016(0.999, 1.033]
    LagO
    1.015(0.996, 1.035]
    3-day avg
    1.009(0.987, 1.032]
    5-day avg
    1.009[0.983, 1.036]
    7-day avg
    Case-Crossover:
    1.017(0.998, 1.036]
    LagO
    1.015(0.993, 1.037]
    3-day avg 1.008(0.984, 1.033]
    5-day avg
    1.003(0.976, 1.031]
    7-day avg
    PM Increment: 26 pg/m3
    % Change in Daily Admission [Cl]:
    Age <65
    Current day mean: -0.9 [-6.8,5.4]
    2-day mean: -1.3 [-8.5,6.6]
    3-day mean: 1.9 [-6.5,11]
    Age 65+
    Current day mean: 3.3 [-1.7,8.6]
    2-day mean: 5 [-1.5,11.9]
    3-day mean: 1.2 [-6.1,9.1]
    
    
                                     Dose-response Investigated? No
                                     Statistical Package: S-Plus
                                     Lags Considered: Current to 3-day
    December 2009
    E-233
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Galan et al. (2003, 0874081
    Period of Study: 1995-1998
    Location: Madrid, Spain
    Hospital Admissions
    Outcome (ICD): Asthma (493)
    Age Groups: All ages
    Study Design: Time series
    N: 555,1 53 at-risk
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (min-max):
    32.1 (11.2-108.6)
    SD=12.1
    Monitoring Stations: 13
    PM Increment: 10 pg/m3
    RR Estimate [Cl]:
    Single-pollutant
    Current-day lag: 1.011 (0.980-1.042)
    1-day lag: 1.006 (0.976-1.037)
                                       Statistical Analyses: GAM,
                                       autoregressive Poisson regression
    
                                       Covariates: Temperature, relative
                                       humidity, pollen, yr, day of the week,
                                       public holiday
    
                                       Season: NR
    
                                       Dose-response Investigated? No
    
                                       Statistical Package: S-Plus
    
                                       Lags Considered: 0,1, 2, 3, and 4 day
                                       Copollutant (correlation):
                                       S02:r = 0.581
                                       N02:r = 0.717
                                       03:r =-0.188
    
                                       Other variables:
                                       O.europaea: r = -0.066
                                       Plantagosp.: r = -0.202
                                       Poaceae: r = -0.132
                                       Urticaceae: r = -0.104
                                       Temp: r = -0.122
                                       Humidity: r = 0.119
                                       2-day lag: 1.008 (0.978-1.038)
    
                                       3-day lag: 1.039 (1.010-1.068)
    
                                       4-day lag: 1.027 (0.999-1.056)
    
                                       Adjustment for pollen (PM10 3-day lag)
    
                                       O.europaea: 1.041 (1.011-1.071)
    
                                       Plantagosp.: 1.046 (1.017-1.076)
    
                                       Poaceae: 1.043 (1.015-1.073)
    
                                       Urticaceae: 1.038 (1.009-1.068)
    
                                       All four: 1.045 (1.016-1.074)
    Reference: Hajat et al. (2002, 0303581
    
    Period of Study: Jan 1992-Dec 1994
    
    Location: London,  England
    Family Practice consultations
    
    Outcome: Upper Resp Disease
    (excluding allergic rhinitis) (460-3),
    (465), (470-5), (478)
    
    Age Groups: 0-14,
    
    15-64, >65yr
    
    Study Design: Time series
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 28.5 (13.7) pg/m3
    
    Percentiles: 10th: 15.8
    
    90th: 46.5
    
    Monitoring Stations: 1
                                       N: 268,718-295,740 registered patients  Copollutant: NR
    
                                       Statistical Analyses: Poisson
                                       regression, GAM, LOESS smoothers,
                                       default convergence criteria
    
                                       Covariates: Long term trends, pollen
                                       counts, flu, meteorological variables
    
                                       Season: All yr
    
                                       Dose-response Investigated? No
    
                                       Statistical Package: SPLUS
    
                                       Lags Considered: 2-3
    PM Increment: All Year: 18
    
    Warm Season: 15
    
    Cold  Season: 20
    % Change, Single Pollutant Models:
    All Year: Ages
    0-14:2.0[-0.2, 4.2] Lag 3
    Ages 15-64: 5.7[2.9, 8.6]
    Lag 2
    Ages>65:10.2[5.3,15.3] Lag 2
    Warm Season: Ages 0-14:1.1[-2.4, 4.8]
    Lag3
    Ages 15-64: 6.0[2.7, 9.4]
    Lag 2
    Ages >65: 0.1 [-7.7, 8.5] Lag 2
    Cold  Season: Ages 0-14: 2.7[-0.1,  5.5]
    Lag3
    Ages 15-64: 3.6[1.0, 6.4]
    Lag 2
    Ages>65:18.9[11.7, 26.7] Lag 2
    % Change, 2 Pollutant Models:
    0-14  Yr
    PM10w/N02:3.8[1.6, 6.1]
    PMi0w/03:1.8[-0.4, 3.9]
    PM10w/S02:2.0[-0.6, 4.6]
    15-65Yr
    PMi0w/N02:2.8[0.7, 4.9]
    PMi0w/03:4.8[2.6, 7.0]
    PMi0w/S02:4.8[2.2, 7.5]
    >65Yr
    PM10w/N02:4.6[0.5, 8.8]
    PM10w/03:10.7[5.7,  16.0]
    PM10w/S02:10.6[4.5, 17.1]
    December 2009
                                    E-234
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Hanigan et al. (2008,
    1565181
    Period of Study: 1996-2005 (Apr-Nov
    of each yr)
    
    Location: Darwin, Australia
    Outcome: Cardiorespiratory Disease
    HA (ICD 9: 390-519
    
    ICD10:IOO-99SJOO-99)
    
    Age Groups: NR
    
    Study Design: Time series
    
    N: 8279 events
    
    Statistical Analyses: Poisson
    regression
    
    Covariates:  Indigenous status,
    
    Dose-response Investigated? No
    
    Statistical Package: R
    
    Lags Considered: Lags 0-3
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 21.2 (8.2)
    
    Range: 55.2
    
    Monitoring Stations: 2 (monitored &
    modeled)
    
    Copollutant: NR
    
    Co-pollutant Correlation
    
    N/A
    PM Increment: 10 pg/m
    
    Percent Change (Lower Cl, Upper Cl),
    lag:
    
    Total Respiratory: 4.81 (-1.04,11.01),
    lagO
    
    Total Resp., Indigenous: 9.40 (1.04,
    18.46), lag 0
    
    Total Resp., Non-Indigenous: 3.14 (-
    2.99, 9.66), lag
    
    Resp. Infection, Indigenous: 15.02
    (3.73, 27.54), lag 3
    
    Resp. Infection, Non-Indigenous: 0.67 (-
    7.55, 9.61), Iag3
    
    Asthma Indigenous: 16.27 (3.55,
    40.17), lag 1
    
    Asthma Non-Indigenous: 8.54 (-5.60,
    24.80), lag 1
    
    *Fig 3. percent change in hospital
    admissions per 10 pg/m3 increase in
    PM10
    Reference: Hanigan et al. (2008,
    1565181
    Period of Study: 1996-2005 (Apr-Nov
    of each yr)
    
    Location: Darwin, Australia
    Hospital Admissions/ED visits
    
    Outcome (ICD-9 or ICD-10):
    
    Daily emergency hospital admissions
    for total respiratory (ICD-9: 460-519
    
    ICD-10: JOO-J99), asthma (ICD-9: 493
    
    ICD-10:J45-J47), COPD (ICD-9:
    490-492, 494-496
    
    ICD-10: J40-J44, J47, J67), and
    respiratory infections (ICD-9: 461-466,
    480-487, 514
    
    ICD-10: JOO-J22).
    
    Age Groups Analyzed: All
    
    Study Design: Time series
    
    N: 8,279 hospital admissions
    
    Statistical Analyses: Poisson
    generalized linear models
    
    Covariates: Indigenous status, time in
    days, temperature, relative humidity,
    day of the week, influenza epidemics,
    change between ICD editions, holidays,
    yrly population
    
    Season: Apr-Nov (corresponding to the
    dry season)
    
    Dose-response Investigated? No
    
    Statistical package: R version 2.3.1
    
    Lags Considered: Lag 0 -3
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD range): 21.2 (8.2-55.2)
    
    Monitoring Stations: N/A (see notes)
    
    Copollutant (correlation): NR
    PM Increment: 10 pg/m
    
    Percent change [96% Cl]:
    Overall respiratory disease:
    Lag 0:4.81 [-1.04,11.01]
    Lag 0 (indigenous people):
    9.40 [1.04, 18.46]
    Lag 0 (non-indigenous people):
    3.14[-2.99,9.66]
    In unstratified analyses, the subgroups
    of respiratory infections,  asthma, and
    COPD all had positive associations with
    PM10 Lag 0.
    Asthma:
    Lag 1 (indigenous people):
    16.27 [-3.55, 40.17]
    Lag 1 (non-indigenous people):
    8.54
    [-5.60, 24.80]
    Respiratory infections:
    Lag 3 (indigenous people):
    15.02 [3.73, 27.54]
    Lag 3 (non-indigenous people):
    0.67 [-7.55, 9.61]
    Notes:
    
    Fig 3: Associations between
    hospitalizations for non-indigenous and
    indigenous people with estimated
    ambient PMi0.
    
    Summary of Fig 3: Confidence
    intervals were wide, but indigenous
    people generally had stronger
    associations  with PMi0 than non-
    indigenous people. Daily PMi0 exposure
    levels were estimated for the  population
    of the city from visibility data using a
    previously validated models.
    December 2009
                                    E-235
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Hapcioglu et al. (2006,
    0932631
    Period of Study: Jan 1997-Dec 2001
    Location: Istanbul, Turkey
    Hospital Admissions
    Outcome (ICD-9): COPD (ICD: NR)
    Age Groups: NR
    Study Design: Time series
    N: 1586 patients
    Statistical Analyses: Multiple stepwise
    regression, Pearson correlation
    Covariates: Humidity, temperature, and
    pressure
    Season: Summer, fall, winter, spring
    Dose-response Investigated? No
    Statistical Package: SPSS
    Lags Considered: NR
    Pollutant: PM,0
    Averaging Time: 1 mo
    Mean (SD): NR
    Monitoring Stations: 1
    Copollutant: NR
    Correlation with COPD:
    r = 0.28
    p = 0.03
    Adjfortemp:r = 0.16
    p = 0.23
    PM Increment: NR
    Notes: RRs only provided for season,
    notPM
    Reference: Hwang and Chan (2002,
    0232221
    Period of Study: 1998
    Location: Taiwan
    Clinic visits
    Outcome: LRI
    466, 480-486 (acute bronchitis, acute
    bronchiolitis, pneumonia)
    Age Groups: 0-14 yr, 15-64, 65+ yr
    Study Design: Cluster analysis of small
    study areas
    N: 50 communities
    Statistical Analyses: GLM to model
    temporal patterns, hierarchical model to
    obtain estimates across 50 communities
    Covariates: Day of week, temperature,
    dew point, summer/Winter
    Season: All
    Dose-response Investigated? Yes
    Statistical Package: NR
    Lags Considered: 0-2
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (SD): 58.9 pg/m3 (14.0)
    Range (Min, Max): 33.3, 83.1 pg/m3
    PM Component:
    Monitoring Stations: 59
    Notes: Number Of stations estimated
    from  fig.
    Copollutant: NR
    PM Increment:
    10% Increase In PM,0 (5.9 pg/m
    Percent Change:
    0-14
    0.5%(-0.1,0.8]LagO
    [-0.3, 0.3] Lag1
    0.3 [0.0, 0.6] Lag2
    15-64
                                                                                                              0.6
                                                                                                              0.2
        0.2, 0.9] LagO
                                                                                                                 -0.1,0.5] Lag 1
                                                                                                              0.3 [0.0, 0.6] Lag2
                                                                                                              65+
                                                                                                              0.8 [0.4,1.1] LagO
                                                                                                              0.3 [-0.1, 0.6] Lag 1
                                                                                                              0.5[0.1,0.8]Lag2
                                                                                                              All Ages
                                                                                                              0.5 [0.2, N0.8] LagO
                                                                                                              [-0.3,  0.3] Lag1
                                                                                                              0.3 [0.0, 0.6] Lag2
    Reference: Jaffe et al. (2003, 0419571
    Period of Study: July 1991 -June
    1996
    Location: Cincinnati, Cleveland,
    Columbus, Ohio
    ED visits
    Outcome (ICD10): Asthma (493)
    Age Groups: Age 5-34 yr
    Study Design: Time-series
    N: 4,416 recipients
    Statistical Analyses: Poisson
    regression, GAM
    Covariates: City, day of week, wk, yr,
    minimum temperature, dispersion
    parameter
    Season: Jun-Aug only
    Dose-response Investigated? Yes
    Statistical Package: NR
    Lags Considered: 0-3 days
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD):
    Cincinnati: 43.0(16.4)
    Cleveland: 60.8(28.4)
    Columbus: 37.4(16.3)
    Range (Min, Max):
    Cincinnati: (16,90)
    Cleveland: (12,183)
    Columbus: (7,87)
    Monitoring Stations: 3
    Copollutant (correlation):
    Cincinnati:
    PM10
    03r = 0.42
    N02r = 0.36
    S02r = 0.31
    Cleveland:
    PM10
    03r = 0.42
    N02r = 0.34
    S02r = 0.29
    Columbus:
    PM10
    03r = 0.51
    N02r=Na
    S02r = 0.42
    PM Increment: 50 pg/m
    % Change
    Asthma
    Cincinnati:-22%[-49,-19] Lag 3
    Cleveland: 12%[0,27] Lag 2
    Columbus: 32%[-6,-85] Lag 3
    Ar Estimate [Lower Ci, Upper Ci]
    Lag:
    Asthma
    Cincinnati: PMi0: Nr
    Cleveland: PM,0:1.32
    Columbus: PM,0: 3.62
    Notes: Dose response was investigated
    by assessing the relationship between
    odds of ed visit by quintile of PMi0.
    Results are displayed in Fig. "no
    consistent effects for all three cities
    were observed for PMi0." Rate ratios
    were also reported for each city.
    December 2009
                                    E-236
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Jalaludin et al. (2004,
    0565951
    
    Period of Study: Feb-Dec 1994
    
    Location: Sydney, Australia
    Doctor Visits
    
    Outcome (ICD- NR): Respiratory
    symptoms (wheeze, dry cough, and wet
    cough), asthma medication use, and
    doctor visits for asthma
    
    Age Groups: Primary school children
    
    Study Design: Longitudinal cohort
    study
    
    N: 125 children
    
    Statistical Analyses: GEE logistic
    regression models
    
    Covariates: Temperature, humidity,
    daily pollen count, daily alternaria count,
    number of h spend outdoors, season
    
    Season: Fall (Feb-Apr), winter (May-
    Aug), spring/summer (Sep-Dec)
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 0-2 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 22.8 (13.8)
    
    Monitoring Stations: 4
    
    Copollutant (correlation):
    
    03:r = 0.13
    
    N02:r = 0.26
    
    Other variables:
    
    Temp: r = 0.04
    
    Humidity: r = -0.29
    
    Total pollen: r = 0.04
    
    Alternaria: r = 0.04
    PM Increment: IQR (pg/m )
    Same day: 12.0
    1-day lag: 12.02
    2-day lag: 12.25
    2-day avg: 11.15
    5-day avg: 10.23
    OR Estimate [Cl]:
    
    Doctor Visits for Asthma
    Same day: 1.11 [1.04,1.19]
    1-day lag: 1.10 [1.02,1.19]
    2-day lag: 1.15 [1.06,1.24]
    2-day avg: 1.11 [1.03,1.20]
    5-day avg: 1.14 [0.98,1.31]
    
    Prevalence of Doctor Visits for
    Asthma:
    
    Quartile 1:0.50 (mean PM = 12.4)
    Quartile 2: 0.38 (mean PM = 17.2)
    Quartile 3: 0.65 (mean PM = 23.0)
    Quartile 4: 0.63 (mean PM = 38.3)
    
    Notes: ORs and prevalence are also
    provided for wheeze, dry cough, wet
    cough, inhaled |32-agonist use, and
    inhaled corticosteroid use. None were
    statistically significant.
    December 2009
                                    E-237
    

    -------
    Reference
    Design & Methods
    Reference: Johnston et al. (2007, Hospital Admissions/ED visits
    	 Outcome (ICD-10):
    Period of Study: 2000, 2004, 2005
    Apr-Nov of each yr) Al1 respiratory conditions (JOO-J99),
    
    Location: Darwin, Australia
    including asthma (J45-46), COPD
    (J40-J44
    (JOO-J22
    , and respiratory infections
    Age Groups Analyzed: All
    Study Design: Case-crossover
    N: 2466 emergency admissions
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24 h
    Median: 17.4
    
    IQR: 13.6-22.3
    10-90th Percentile: 10.3-27.7
    Range: 1.1-70.0
    Monitoring Stations: 1
    Copollutant (correlation): NR
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    OR Estimate [96% Cl]: All respiratory
    conditions: Lag 0:1. 08 [0.98-1. 18]
    Lag 0 (indigenous): 1.17 [0.98-1. 40]
    COPD: Lag 0:1. 21 [1.0-1.47]
    Lag 0 (indigenous): 1.98 [1.10-3.59]
    Asthma: Lag 0:1. 14 [0.90-1. 44]
    Asthma* COPD: Lag 0:1. 19
    [1.03-1.38]
                                         Statistical Analyses: Conditional
                                         logistic regression
    
                                         Covariates: Weekly influenza rates,
                                         temperature, humidity, days with rainfall
                                         >5mm, public holidays, school holiday
                                         periods (for respiratory conditions only)
    
                                         Season: Apr-Nov (dry season)
    
                                         Dose-response Investigated? No
    
                                         Statistical package: NR
    
                                         Lags Considered: 0-3 days
                                             Notes: Fig 1: Adjusted OR and 95% Cl
                                             for hospital admissions for all
                                             respiratory conditions per 10 pg/m  rise
                                             in PM10 for the same day and lags up to
                                             3 days, overall and stratified by
                                             indigenous status.
    
                                             Summary of Fig 1 results: Marginally
                                             significant positive association at Lag 0
                                             in overall study population.  Larger
                                             marginally significant positive
                                             association among indigenous people.
    
                                             Fig 2: OR and 95% Cl for hospital
                                             admissions for COPD. Summary of Fig
                                             2 results: Marginally significant positive
                                             associations at Lag 0 and Lag 1 in
                                             overall study population and among
                                             non-indigenous people.  Large,
                                             statistically significant positive
                                             association at Lag 0 for  indigenous
                                             people, with smaller, non-significant
                                             positive associations at  Lag 1 and Lag2.
    
                                             Fig 3: OR and 95% Cl for hospital
                                             admissions for asthma.
    
                                             Summary of Fig 3 results: Positive,
                                             non-significant (sometime marginally
                                             significant) associations at Lag 0, Lag 2,
                                             and Lag 3 for overall population and
                                             indigenous status strata.
    
                                             Fig 4: OR and 95% Cl for hospital
                                             admissions for respiratory infections.
    
                                             Summary of Fig 4 results: Negative
                                             associations at Lag 2 and Lag 3 in all
                                             population strata.
    December 2009
    E-238
    

    -------
    Reference
    Reference: Kim et al. (2007, 0928371
    Period of Study: 2002
    Location: Seoul, Korea
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Ko et al. (2007, 0916391
    Period of Study: Jan 2000-Dec 2004
    Location: Hong Kong, China
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Ed Visits
    Outcome (ICD10): Asthma (J45), (J46)
    Age Groups: All Ages
    Study Design: Cass-Crossover
    
    N: 92, 535 Visits
    Statistical Analyses: Conditional
    Logistic Regression, Relative Effect
    Modification (Rem)
    Covariates: Time Trend, Season, Daily
    Mean Temperature, Relative Humidity,
    Air Pressure. Sep As Modifier Of Air
    Pollution Asthma Visit Association.
    Season: All Year
    Dose-response Investigated? No
    Statistical Package: Nr
    Lags Considered: 0-2 days
    
    
    
    
    Ed Visits
    Outcome (ICD-9): COPD: chronic
    bronchitis (491), emphysema (492),
    chronic airway obstruction (496)
    Age Groups: All Ages
    
    Study Design: Time Series
    
    N: 15 hospitals, 119,225 admissions
    Statistical Analyses: Poisson
    regression, gam with stringent
    convergence criteria, aphea2 protocol.
    Covariates: Time trend, season,
    temperature, humidity, other cyclical
    factors, day, day of wk, holidays
    Season: All yr, interactions with season
    tested
    
    Dose-response Investigated? No
    
    Statistical Package: Splus 4.0
    Lags Considered: 0-5 days
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 8 h
    Mean (SD): Daily Concentration: 67.6
    (39.0) pg/m3
    Relevant Exposure Term (Difference
    Between Concentration On Event Day
    And Mean Of Concentrations On
    Control Days): 26.0 (19.7)
    Percentiles: SOth(Median): Daily
    Concentration: 61.9
    Relevant Exposure Term: 21.6
    Range (Min, Max): Daily
    Concentration: (4.9, 302.0)
    Relevant Exposure Term: (0.0, 143.1)
    Monitoring Stations: 3
    Copollutant: Nr
    
    
    
    
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): 50.1 (23.9) pg/m3
    Percentiles: 25th: 31. 9
    
    SOth(Median): 44.5
    
    75th: 64.1
    Range (Min, Max): (13.6, 172.2)
    Monitoring Stations: 14 Stations
    Copollutant (correlation):
    PM10:
    S02r = 0.436
    N02r = 0.229
    
    03r = 0.421
    
    PM25 r = 0.952
    
    
    Effect Estimates (95% Cl)
    PM Increment: 47.4 pg/m3
    Rr Estimate For Asthma (Stratified
    By Sep):
    Individual Level Sep:
    Quintile1-1.06[1.02 1.09]
    
    Quintile2-1.07[1.04 1.10]
    Quintile3-1.06[1.03 1.10]
    Quintile 4-1 .03[0.99 1.07]
    Quintile5-1.10[1.05 1.14]
    Regional Level Sep:
    Quintile 1-1 .04[0.99 1.10]
    Quintile2-1.03[1.00 1.07]
    Quintile3-1.05[1.03 1.08]
    Quintile4-1.06[1.02 1.10]
    Quintile5-1.09[1.06, 1.13]
    Total-1.06[1.04, 1.08], 3D Ma
    Notes: Relative Effect Modification
    (Rem) Estimates Presented In Paper.
    PM Increment: 10 pg/m3
    Rr Estimate
    COPD:
    1.0031.000,1.005 LagO
    1.005 1.002, 1.007 Lag 1
    1.0101.007, 1.012 Lag 2
    1.011 1.008, 1.013] Lag 3
    1.0081.006, 1.011] Lag 4
    1.0071.004, 1.009 Lag5
    1.0051.002, 1.008 Lag 0-1
    1.011 1.008, 1.014] Lag 0-2
    1.0161.013,1.019 Lag 0-3
    1.0201.017, 1.024 Lag 0-4
    1.0241.021, 1.028 Lag 0-5
    
    
    
    
    
    
    
    December 2009
    E-239
    

    -------
    Reference
    Reference: Ko et al. (2007, 0916391
    Period of Study:
    Jan 2000-Dec 2004
    
    Location: Hong Kong, China
    
    
    
    
    
    
    
    
    
    Design & Methods
    Hospital Admission
    Outcome (ICD-9): Asthma (493)
    
    Age Groups: All, 0-14, 15-56,65+
    Study Design: Time series
    N: 69,716 admissions, 15 hospitals
    Statistical Analyses: Poisson
    regression, with GAM with stringent
    convergence criteria.
    Covariates: Time trend, season,
    temperature, humidity, other cyclical
    factors
    Season: All yr, evaluated effect of
    season in analysis
    Dose-response Investigated? No
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24 h
    
    Mean (SD): 52.5(27. 1) pg/m3
    Percentiles: 26th: 30.9
    60th(Median):
    47 1
    HI . i
    75th: 68.8
    Range (Min, Max): (13.4, 198.9)
    
    Monitoring Stations: 14 stations
    Copollutant (correlation):
    PM10:
    S02 r = 0.436
    N02 r = 0.761
    03r = 0.600
    PM25 r = 0.956
    Effect Estimates (95% Cl)
    PM Increment: 10.0 pg/m3
    RR Estimate:
    
    Asthma (Single-pollutant model):
    1.0061.003, 1.010 lagO
    1.0051.002, 1.009 Iag1
    1.0051.002,1.009 lag 2
    1.0081.005, 1.012 Iag3
    1.0061.002, 1.009 lag 4
    1.0060.999,1.006 lag 5
    1.008 1.004, 1.012 ; lag 0-1
    1.0121.008, 1.016 lag 0-2
    1.0151.011, 1.019] lag 0-3
    1.0181.013, 1.022 lag 0-4
    1.0191.015, 1.024 lag 0-5
    Asthma by age group
    0-14: 1.023(1.015, 1.031] lag 0-5
    14-65:1.014(1.006, 1.022] lag 0-5
    *,ŁŁ• -i msM nno 1 moi i^n n_/i
                                       Statistical Package: SPLUS 4.0
                                       Lags Considered: 0-5 days
                                                                          Asthma-Effect of season: 1.148(1.051,
                                                                          1.245] lag 0-5
    Reference: Kuo et al. (2002, 0363101
    Period of Study: 1 yr
    Location: central Taiwan
    
    
    
    Hospital Admissions
    Outcome (ICD-NR): Asthma
    Age Groups: 13-1 6 yr
    Study Design: Cohort
    N: 12,926
    Statistical Analyses: Multiple logistic
    regression, Pearson correlation
    Pollutant: PM,0
    Averaging Time: 1 h
    Mean (min-max): NR
    Range: (54.1-84.3)
    Monitoring Stations: 8
    Copollutant: Values NR
    Notes: Author states that a positive
    PM Increment: NR
    OR Estimate:
    PM10 <65.9 |jg/m3-referent
    PM10 >65.9 pg/m3
    Crude OR: 0.837
    Adj OR: 0.947
    95% Cl: (0.640, 1.401)
    _l
                                       Covariates: Sex, age, residential area
                                       level of parents' education, number of
                                       cigarettes smoked by smokers in the
                                       family, incense burning, frequency of
                                       physical activity
                                       Season: NR
                                       Dose-response Investigated? No
                                       Statistical Package: SAS
                                       Lags Considered: NR
                                       correlation was found between N02 and
                                       PM10
    Reference: Langley-Turnbaugh et al.
    (2005, 0932691
    Period of Study: 2000-2001
    Location: Portland, Bridgeton, and
    Presque Isle, Maine
    Hospital Admissions
    Outcome (ICD-9): Asthma (493xx)
    Age Groups: 0-18 yr, 19+ yr
    Study Design: Time series
    N:NR
    Statistical Analyses: NR
    Covariates: NR
    Season: Winter, spring, summer, fall
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: NR
    Notes: Hospital admissions were used
    to determine seasonality of asthma
    admissions so that PM components
    from those time periods could be
    analyzed
    Pollutant: PM10
    Averaging Time: NR
    Mean (min-max): NR
    Monitoring Stations: NR
    Copollutant: NR
    PM Increment: NR
    RR Estimate [Cl]: NR
    Notes: Portland filters contained more
    PM in the winter (Jan) and Bridgeton
    filters contained more PM in the spring
    (May)
    study analyzed metal components of
    PM,o(Mn, Cu, Pb.As, V, Ni.AI)
    Clinical data shows a strong peak in fall
    and weaker peaks in Jan and May for
    asthma admissions
    December 2009
                                    E-240
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Lee et al. (2002, 0348261
    Period of Study: Dec 1997-Dec 1999
    Location: Seoul,  Korea
    Hospital Admissions
    Outcome (ICD10): Asthma, J45, J46,
    Age Groups: Children <15 yr
    Study Design: Time-Series
    N: 822  days, 6,436 admissions
    Statistical Analyses: Poisson
    regression, GAM, LOESS smoothers.
    Covariates: Days of the week,
    temperature, humidity
    Season: All
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: 0-5, 0-1 ma for 1-2,
    2-3, and 3-4 days
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean(SD):64.0(31.8)|jg/m3
    Percentiles: 26th: 40.5 pg/m3
    50th(Median):59.1|jg/m3
    76th: 80.9 pg/m3
    Range (Min, Max): NR
    Monitoring Stations: 27
    Notes: Copollutant (correlation):
    PMio-S02: 0.585
    PM10-N02: 0.738
    PM10-03: 0.106
    PM10-CO: 0.598
    PM Increment: IQR: 40.4 pg/m
    RR Estimate:
    Single Pollutant:
    1.07(1.04,1.11) lag 1
    Two pollutant models:
    +S02:1.05 (1.01,1.09) lag 1
    +N02:1.03 (0.99,1.07) lag 1
    +03:1.06 (1.03,1.10)lag1
    +00:1.04(1.00,1.08) lag 1
    Three pollutant models:
    +03 +CO: 1.02 (0.98,1.06), lag 1
    Four pollutant models:
    +03 + CO+S02:1.02(0.98, 1.06), lag 1
    Five pollutant model:
    1.016(0.975, 1.059) lag 1
    Notes: Investigated the association
    between outdoor air pollution and
    asthma attacks in children <15 yr.
    Reference: Lee et al. (2006, 0901761
    Period of Study: Jan 1997-Dec 2002
    Location: Hong Kong, China
    Hospital Admission
    Outcome: Asthma (493)
    Age Groups: <18yr
    Study Design: Time series
    N: 26,663 asthma admissions for
    asthma and 5821 admissions for
    influenza
    Statistical Analyses: Poisson
    regression, GAM
    Covariates: Temperature, atmospheric
    pressure,  relative humidity
    Season: All
    Dose-response Investigated? No
    Statistical Package: SAS 8.02
    Lags Considered: 0-5
    Notes: Controls were admissions for
    influenza ICD9 487
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): 56.1 (24.2)
    Percentiles: 26th: 37.3
    50th(Median):51.1
    75th: 70.7
    Monitoring Stations: 10
    Notes: Copollutant (correlation):
    PM10-PM25: 0.90
    PM,o-S02: 0.39
    PM,o-N02: 0.80
    PM10-03: 0.60
    PM Increment: IQr = 33.4
    Percent Increase:
    Single pollutant model:
    4.97 [2.96, 7.03], lag 0
    5.71 [3.78, 7.68], lag 1
    6.40 [4.51, 8.32], lag 2
    7.25 [5.38, 9.16], lag 3
    7.45 [5.58, 9.35], lag 4
    5.96 [4.11, 7.85], Iag5
    Multipollutant model (S02, CO, N02, 03)
    3.67 [1.52,5.86] Iag4
    Reference: Lin et al. (2005, 0878281
    Period of Study: 1998-2001
    Location: Toronto, North York, East
    York, Etobicoke, Scarborough, and York
    (Canada)
    Hospital Admissions
    Outcome (ICD-9): Respiratory
    infections including laryngitis, tracheitis,
    bronchitis, bronchiolitis, pneumonia,
    and influenza (464, 466, 480-487)
    Age Groups: 0-14 yr
    Study Design: Bidirectional case-
    crossover
    N: 6782 respiratory infection
    hospital izations
    Statistical Analyses: Conditional
    logistic regression (Cox proportional
    hazards model)
    Covariates: Daily mean temp and dew
    point temp
    Season: NR
    Dose-response Investigated? No
    Statistical Package: SAS 8.2 PHREG
    procedure
    Lags Considered: 1-7  day avg
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (min-max):
    20.41 (4.00-73.00)
    SD= 10.14
    Monitoring Stations: 4
    Copollutant (correlation):
    PM25:r = 0.87
    PMi0.25:r = 0.76
    CO: r = 0.10
    S02:r = 0.48
    N02:r = 0.54
    03:r = 0.54
    PM Increment: 12.5 pg/m
    OR Estimate [Cl]:
    Adjusted for weather
    4-day avg: 1.22 [1.10,1.34]
    6-day avg: 1.25 [1.11,1.40]
    Adj for weather and other gaseous
    pollutants
    4-day avg: 1.14 [0.99,1.32]
    6-day avg: 1.20 [1.01,1.42]
    Notes: OR's were also categorized into
    "Boys" and "Girls," yielding similar
    results
    December 2009
                                    E-241
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Lin et al, (2008,1268121
    Period of Study: 1991-2001
    Location: New York State, U.S.
    Outcome: Respiratory hospital
    admissions (ICD-9 466, 490-493, 496
    Study Design: Time-series
    Covariates: Demographic
    characteristics, PM10, meteorological
    conditions, day of the week,
    seasonality, long term trends and
    different lag periods
    Statistical Analysis: GAM and case-
    crossover design at the regional level
    and Bayesian  hierarchical model at the
    state level
    Age Groups:  Children 0-17 yr
    Pollutant: 03 (PMi0 is secondary)
    Averaging Time: 24 h
    Mean (SD) Unit: 19.56 (10.92) pg/m3
    Range (Min, Max): 1.0, 90.00
    Copollutant (correlation):
    Given in Fig 3
    All PMio results are given in Fig 3
    Reference: Lin et al. (2002, 0260671
    Period of Study: Jan 1981-Dec 1993
    Location: Toronto
    Hospital Admissions
    Outcome (ICD-9): Asthma (493)
    Age Groups: 6-12 yr
    Study Design: Uni- and bi-directional
    case-crossover (UCC, BCC) and time-
    series (TS)
    N: 7,319 asthma admissions
    Statistical Analyses: Conditional
    logistic regression, GAM
    Covariates:  Maximum and minimum
    temp, avg relative humidity
    Season: Apr-Sep,  Oct-Mar
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: 1-7 day avg
    Pollutant: PM10
    Averaging Time: 6 days (predicted
    daily values)
    Mean (min-max):
    30.16(3.03-116.20)
    SD= 13.61
    Monitoring Stations: 1
    Copollutant (correlation):
    PM25:r = 0.87
    PM10.25:r = 0.83
    CO: r = 0.38
    S02:r = 0.44
    N02:r = 0.52
    03:r = 0.44
    PM Increment: 14.8 pg/m
    RR Estimate [CI]:
    Adj for weather and gaseous pollutants
    BCC 5-day avg: 0.99 [0.90,1.09]
    BCC 6-day avg: 1.01 [0.90,1.12]
    TS 5-day avg: 1.03 [0.95,1.11
    TS 6-day avg: 1.02 [0.94,1.11
    Boys-adj for weather
                                                                                                                                   1.04,1.17
                                                                                                                                   1.02,1.17
                                                                                                                                   0.98,1.09
                                                                                                                                   0.95,1.08:
                                                                                                                TS 1-day avg:"1.03 [0:99,1.07] '
                                                                                                                TS 2-day avg: 1.01 [0.96,1.05]
                                                                                                                Girls-adj for weather
    UCC 1-day avg: 1.10
    UCC 2-day avg: 1.10
    BCC 1-day avg: 1.04
    BCC 2-day avg: 1.01
                                                                                                                UCC 1-day avg: 1.07
                                                                                                                UCC 2-day avg: 1.15
                                                                                                                BCC 1-day avg: 0.99
                                                                                                                BCC 2-day avg: 1.03
                       0.99,1.16
                       1.04,1.26
                       0.92,1.06'
                       0.95,1.12:
                                                                                                                TS1-day avg: 0.99 [0.94,1.04]
                                                                                                                TS 2-day avg: 1.02 [0.96,1.08]
                                                                                                                Notes: The author also provides RR
                                                                                                                using UCC, BCC,  and TS analysis for
                                                                                                                female and male groups for days 3-7,
                                                                                                                yielding similar results
    Reference: Linares et al. (2006,
    0928461
    Period of Study: Jan 1995-Dec 2000
    Location: Madrid, Spain
    Outcome: Respiratory system diseases
    460-519, bronchitis 460-496,
    pneumonia 480-487
    Age Groups: <10yr
    Study Design: Time series
    N: -15,000 admissions, 2192 days
    Statistical Analyses: Poisson
    regression, dummy variables to adjust
    for season and weather
    Covariates: Temperature, difference in
    barometric pressure, relative humidity,
    pollen counts, influenza epidemics
    Season: All
    Dose-response Investigated? Yes
    Statistical Package: S-Plus 2000
    Lags Considered: 0-13
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): 33.4 pg/m3, (13.7)
    Range (Min, Max): 6,109 pg/m3
    Monitoring Stations: 24
    Notes: Copollutant (correlation):
    PM,o-S02: 0.532
    PMio-03: -0.289
    PM10-: 0.721
    PM10-N02: 0.711
    PM Increment: 10 pg/m
    RR Estimate
    Bronchitis
    1.09 [1.01,1.16] lag 2
    AR% Estimate
    Bronchitis
    7.9 [Cl NR] Iag2
    Notes: Only statistically significant
    relative and attributable risks were
    presented by the authors.
    The authors conducted multivariate
    modeling using a linear term to
    represent PM10. They also report an
    apparent estimated PMio effect
    threshold of 60 pg/m3, based on
    examination of a scatter plot of
    respiratory emergency hospital
    admissions and PMio levels.
    December 2009
                                    E-242
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Luginaah, et al. (2005,
    0573271
    Period of Study: Apr 1995-Dec 2000
    Location: Windsor, Ontario, Canada
    Hospital Admission/ED:
    admission
    Outcome: All respiratory: 460-519
    Age Groups: All, 0-14,15-64, and >65
    Study Design: Times-series, bi-
    directional case-crossover
    N: 4214 admissions
    Statistical Analyses: Poisson
    regression, GAM w/ stringent
    convergence criteria or natural splines,
    conditional logistic regression
    Covariates: Age, sex
    Maximum & minimum temperature,
    change in barometric pressure from
    previous day
    Season: All
    Dose-response Investigated? No
    Statistical Package: S-Plus
    Lags Considered: 1-3
    Pollutant: PM,0
    Averaging Time: 24-h max
    Mean (SD): 50.6 ,(35.5)
    Range (Min, Max): 9, 349
    Monitoring Stations: 4
    Notes: Copollutant (correlation):
    PM10-N02: 0.33
    PM10-S02: 0.22
    PM,o-CO: 0.21
    PM,o-03: 0.33
    PM Increment: Interquartile range
    (75th-25th) 31 pg/m3
    RR Estimates (Time Series)
    All Age Groups Females
    0.996 [0.950, 1.044], lag 1
    1.015 [0.963, 1.069], lag 2
    1.022 [0.968, 1.078], lag 3
    All Age Groups Males
    1.008 [0.965, 1.054], lag 1
    1.036 [0.986, 1.089], lag 2
    1.027 [0.974, 1.083], lag 3
    RR Estimates (Case Crossover)
    All Age Groups Females
    1.034 [0.974, 1.098], lag 1
    1.045 [0.972, 1.124], lag 2
    1.054 [0.970, 1.145], lag 3
    All Age Groups Males
    0.997 [0.942, 1.056], lag 1
    1.022 [0.953, 1.097], lag 2
    1.008 [0.930, 1.092], lag 3
    Notes: Results, stratified by age group
    available in manuscript.
    Reference: Martins et al. (2002,
    0350591
    Period of Study: May 1996-Sep 1998
    Location: Sao Paulo, Brazil
    Hospital Admission/ED:
    ER visits
    Outcome (ICD10): Chronic lower
    respiratory disease (CLRD) (40-47)
    Includes chronic bronchitis,
    emphysema, other COPDs, asthma,
    bronchiectasia
    Age Groups: >64 yr
    Study Design: Time series
    N: 712  for CLRD
    1 hospital
    Statistical Analyses: Poisson
    regression GAM, LOESS smoothers, no
    mention of stringent criteria
    Covariates: Day of week, time
    minimum temperature, relative humidity
    Season: All
    Statistical Package: S-Plus
    Lags Considered: 2-7 3 day ma
    Pollutant: PM10
    Averaging Time: Daily
    Mean (SD): 60.0 pg/m3, (26.3)
    Range (Min, Max):
    22.8. 186.5 pg/m3
    PM Component: None
    Monitoring Stations: 12
    Notes: Copollutant (correlation):
    PM,o-CO: 0.73
    PM10-N02:0.83
    PM10-S02: 0.72
    PM10-03: 0.35
    PM Increment: 1 pg/m
    Regression Coefficients (SE):
    0.0024(0.0023), 6 day ma
    Notes: % Increase (SD) for ER visits
    per 2435 pg/m3 (IQR) PM,o (lag 6 day
    ma) presented graphically in text.
    December 2009
                                    E-243
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Masjedi et al. (2003,
    0521001
    
    Period of Study: Sep 1997-Feb 1998
    
    Location: Tehran, Iran
    Hospital Admissions
    
    Outcome (ICD-9): Acute asthma and
    COPD exacerbations (ICD: NR)
    
    Age Groups: NR
    
    Study Design: Time series
    
    N: 355 patients
    
    Statistical Analyses: Multiple stepwise
    regression, autoregression method
    (time series), Pearson correlation
    
    Covariates: NR
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 3-, 7-, and 10-day
    mean
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (min-max):
    
    108.41 (14.5-506.60)
    
    SD = 59.55
    
    Monitoring Stations: 3
    
    Copollutant: NR
    PM Increment: NR
    
    Results:
    Time-series analysis
    
    Asthma: (3 = 0.002
    p = 0.32
    COPD: (3 = 0.004
    p = 0.02
    Total Acute Resp Conditions: (3 = 0.006
    p = 0.27
    Correlation of 3-day mean
    
    Asthma: r =-0.21
    (3 =-0.16
    p = 0.08
    Correlation of weekly mean
    
    Asthma: r =-0.27
    (3 = -0.008
    p = 0.12
    Correlation of 10-day mean
    
    Asthma: r = -0.38
    (3 = -0.066
    p = 0.089	
    Reference: McGowan et al. (2002,
    0303251
    
    Period of Study: Jun 1988-Dec 1998
    
    Location: Christchurch, New Zealand
    Hospital Admissions
    
    Outcome (ICD-9): Pneumonia (480-
    487), acute respiratory infections (460-
    466), chronic lung diseases (491-492,
    494-496), asthma (493)
    
    Age Groups: <15 yr, 15-64, 65+
    
    Study Design: Time series
    
    N: 20,938 admissions
    
    Statistical Analyses: GAM with log
    link, Linear Regression Model
    
    Covariates: Wind speed, relative
    humidity, temperature
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: S-PLUS
    
    Lags Considered: 0-6 days
    Pollutant: PM10
    
    Averaging Time: 24 h
    
    Mean (min-max):
    
    25.17(0-283)
    
    SD = 25.49
    
    Monitoring Stations: 1
    
    Copollutant: NR
    PM Increment: 14.8 fjg/nr (IQR)
    
    % Increase [Cl]:
    Respiratory Admissions (2-day lag)
    0-14 yr: 3.62 [2.34,4.90]
    15-64 yr: 3.39 [1.85,4.93]
    65+yr: 2.86 [1.23,4.49]
    All ages: 3.37 [2.34,4.40]
    Overall
    Acute respiratory infections: 4.53
    [2.82,6.24]
    Pneumonia/influenza: 5.32 [3.46,7.18]
    Chronic lung diseases: 3.95 [2.15,5.75]
    Asthma: 1.86 [0.48,.3.24]
    Total Respiratory Admissions
    Same day lag: 2.52 [1.49,3.55]
                                                                                                               1-day lag: 2.56
                                                                                                               2-day lag: 3.37
                                                                                                               3-day lag: 3.09
                                                                                                               4-day lag: 3.13
                                                                                                               5-day lag: 3.21
                                                                                                               6-day lag: 3.09
                                                      1.53,3.59'
                                                      2.34,4.40:
                                                      2.06,4.12:
                                                      2.10,4.16:
                                                      2.18,4.24:
                                                      2.06,4.12:
    December 2009
                                    E-244
    

    -------
    Reference
    Reference: Medina-Ramon et al.
    (2006, 0877211
    Period of Study: 1986-99
    Location: 36 U.S. Cities
    Design & Methods
    Outcome: 490-496, except 493
    (COPD), 480-487 (Pneumonia)
    Age Groups: 65 + (U.S. Medicare
    beneficiaries)
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean(SD):30.4|jg/m3(5.1)
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    % change [Lower Cl, Upper Cl]
    lag:
                                        Study Design: Case crossover
                                        N: 578,006 COPD admissions
                                        1,384,813 Pneumonia admissions
                                        Statistical Analyses: Conditional
                                        logistic regression, Meta-analysis using  Copollutant: NR
                                        REML random effects models
                                        Covariates: Mean and variance of daily
                                        summer apparent temperature index, %
                                        65+ living in poverty, % households with
                                        central air-conditioning mortality rate for
                                        emphysema among 65+(surrogate for
                                        smoking history), % PMi0 from traffic
                                        Season: WarmjMay -Sepnd
                                        Cold(Oct-Apr)
                                        Dose-response Investigated? No
                                        Statistical Package: SAS
                                        STATA
                                        Lags Considered: 0-1 days
                                        Monitoring Stations: at least one per
                                        city
                                        Notes: PM10 measurements made
                                        every 2, 3 or 6 days depending on the
                                        city.
                                        COPD warm season
                                        0.81(0.22,1.41) at lag 0
                                        1.47(0.93,2.01) at lag 1
                                        COPD cold season
                                        0.06(-0.40,0.51)atlagO
                                        0.10(-0.30,0.49)atlag1
                                        Pneumonia warm season
                                        0.84 (0.50,1.19) at lag 0
                                        0.79 (0.45,1.13) at lag 1
                                        Pneumonia cold season
                                        0.30 (0.07,0.53) at lag 0
                                        0.14 (-0.17,0.45) at lag 1
    Reference: Meng et al, (2007, 0932751
    Period of Study: Nov 2000-Sep 2001
    Location: Los Angeles and San Diego
    counties, California
    Outcome (ICD-NR): Poorly controlled
    asthma defined as (1) daily or weekly
    asthma symptoms or (2) at least 1 ED
    visit or hospitalization due to asthma
    over the past 12 mo
    Age Groups: >18yr
    Study Design: Time series
    N: 1609 asthma patients
    Statistical Analyses: Logistic
    regression
    Covariates: Age, sex, race/ethnicity,
    poverty level, insurance status, smoking
    behavior, employment, asthma
    medication use, and county
    Season: NR
    Dose-response Investigated: No
    Statistical Package: NR
    Lags Considered: NR
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (26-76th percentile): NR
    Monitoring Stations: NR
                                                                            03:r = -0.72
                                                                            N02:r = 0.83
                                                                            CO: r = 0.42
                                                                            Other variables:
                                                                            Traffic: r = 0.14
    PM Increment: 10 pg/m3
     OR Estimate [Cl]:
    All Adults: 1.08 [0.82,1.43]
    18-64 yr: 1.14 [0.84,1.55]
    65+: 0.84 [0.41,1.73]
    Men: 0.72 [0.42,1.21]
    Women: 1.38 [0.99,1.94]
    Exposure above 44.01 pg/m3 (annual
    concentration)
    All Adults: 1.56 [0.96,2.52]
    18-64 yr: 1.40 [0.81,2.41]
    65+: 2.23 [0.60,8.27]
    Men: 0.80 [0.27,2.41]
    Women: 2.06 [1.17,3.61]
    Notes: This study focused  more on the
    relation between poorly controlled
    asthma and traffic density.
    December 2009
                                    E-245
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95%  Cl)
    Reference: Middleton et al. (2008,
    1567601
    
    Period of Study: 1995-1998,
    2000-2004
    
    Location: Nicosia, Cyprus
    Hospital Admissions/ED visits
    
    Outcome (ICD-NR):
    
    Hospital admissions for all respiratory
    disease (ICD-10: JOO-J99).
    
    Age Groups Analyzed: All, also
    stratified by age (<15 vs..  >15 yr)
    
    Study Design: Time series
    
    N: Statistical Analyses: Generalized
    additive Poisson models
    
    Covariates: Seasonality,  day of the
    week, long- and short-term trend,
    temperature, relative humidity
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical package: STATA SE 9.0,
    and the MGCV package in the R
    software (R 2.2.0)
    
    Lags Considered:  lag 0 -2 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD
    
    median
    
    5%-95%
    
    range):
    
    Cold:
    57.6 (52.5
    
    50.8
    
    20.0-103.0
    
    5.0-1370.6)
    
    Warm:
    53.4 (50.5
    
    30.7
    
    32.0-77.6
    
    18.4-933.5)
    
    Monitoring Stations: 2
    
    Copollutant (correlation): NR
    
    Other variables:
    PM Increment: 10 pg/m  , and across
    quartiles of increasing levels of PMi0
    Percentage increase estimate [Cl]:
    All age/sex groups (Lag 0):
    All admissions: 0.85 (0.55,1.15)
    Respiratory (all): 0.10 (-0.91,1.11)
    Respiratory (cold months):
    -0.33 (-1.47, 0.82)
    Respiratory (warm months):
    1.42 (-0.42, 3.31)
    CVD+RD: 0.56 (-0.21, 1.34)
    Nicosia residents (Lag 0):
    Respiratory (all): 0.25 (-0.84,1.36)
    Respiratory (cold months):
    -0.22 (-1.45, 1.02)
    Respiratory (warm months):
    1.80 (-0.22, 3.85)
    CVD+RD: 0.38 (-0.47, 1.23)
    Males (Lag 0):
    All admissions: 0.96 (0.54,1.39)
    Respiratory (all):-0.06 (-1.37,1.26)
    Respiratory (cold months):
    -0.16 (-1.76,1.46)
    Respiratory (warm months):
    1.10 (-1.47, 3.74)
    CVD+RD: 0.63 (-0.34, 1.62)
    Females (Lag 0):
    All admissions: 0.74 (0.31,1.18)
    Respiratory (all): 0.39 (-1.21, 2.02)
    Respiratory (cold months):
    -0.26 (-2.18,1.70)
    Respiratory (warm months):
    3.27 (-0.00, 6.65)
    CVD+RD: 0.59 (-0.68, 1.87)
    Aged <16yr (Lag  0):
    All admissions: 0.47 (-0.13,1.08)
    Respiratory (all):-0.35 (-1.77,1.08)
    Respiratory (cold months):
    -0.31 (-2.02, 1.42)
    Respiratory (warm months):
    -0.59 (-3.53, 2.45)
    Aged >15yr (Lag  0):
    All admissions: 0.98 (0.63,1.33)
    Respiratory (all): 0.59 (-0.87, 2.07)
    Respiratory (cold months):
    0.02 (-1.76,1.83)
    Respiratory (warm months):
    3.89(1.05,6.80)    	
    Reference: Moore et al. (2008, 1966851
    
    Period of Study: 1983-2000
    
    Location: California's South Coast Air
    Basin
    Outcome: Hospital admissions for
    asthma (ICD-9 493)
    
    Study Design: Time-series
    
    Covariates: Income, demographic and
    residential variables
    
    Statistical Analysis: HRMSM
    
    Age Groups:  Children ages 0-19 yr
    Pollutant: 03 (PM10 secondary)
    
    Averaging Time: Quarterly
    
    Mean (SD) Unit: NR
    
    Range (Min, Max): NR
    Copollutant (correlation):
    1hr03:0.52
    8hr03:0.46
    24 h N02: 0.53
    24 h CO: 0.36
    24 h SO,: 0.13
    Results given are for 03
    December 2009
                                     E-246
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Nascimento et al. (2006,
    0932471
    Period of Study: May 2000-Dec 2001
    Location: Sao Jose dos Campos,
    Brazil
    Hospital Admissions
    Outcome (ICD-10): Pneumonia (J12-
    J18)
    Age Groups: 0-1 Oyr
    Study Design: Time series
    N: 1265 admissions
    Statistical Analyses: GAM, Poisson
    regression
    Covariates: Temperature, humidity
    Season: NR
    Dose-response Investigated? Yes
    Statistical Package: S-Plus, SPSS
    Lags Considered: 0-7 days
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (min-max):
    40.2(3.4-196.6)
    SD = 26.9
    Monitoring Stations: 2
    Copollutant (correlation):
    S02:r = 0.30
    03:r = 0.09
    Other variables:
    Admissions: r = 0.21
    Temp: r = -0.14
    Notes: All p < 0.05
    PM Increment: 24.7 pg/m
    Regression coefficients (SE):
    Same day:-0.00053 (0.00125)
    1-day lag: 0.00029 (0.00057)
    2-day lag: 0.00089 (0.00069)
    3-day lag: 0.00122 (0.00053)*
    4-day lag: 0.00126 (0.00055)*
    5-day lag: 0.00098 (0.00071)
    6-day lag: 0.00035 (0.00056)
    7-day lag:-0.00067 (0.00123)
    *p < 0.05
    Notes: Percent increase over all lag
    days is displayed in Fig 2
    Reference: Neuberger et al. (2004,
    0932491
    Period of Study: 1999-2000 (1 yr
    period)
    Location: Vienna and Lower Austria
    Hospital Admissions
    Outcome (ICD-9): Bronchitis,
    emphysema, asthma, bronchiectasis,
    extrinsic allergic alveolitis, and chronic
    airway obstruction (490-496)
    Age Groups: 3.0-5.9 yr
    7-1 Oyr
    65+
    Study Design: Time series
    N: 366 days (admissions NR)
    Statistical Analyses: GAM
    Covariates: S02, NO, N02, 03,
    temperature, humidity, and day of the
    week
    Season: NR
    Dose-response Investigated? Yes
    Statistical Package: S-Plus 2000
    Lags Considered: 0-14 days
    Pollutant: PM10
    Averaging Time: 24 h
    Maximum daily mean:
    Vienna: 105
    Rural area: NR
    Monitoring Stations: NR
    Copollutant: NR
    PM Increment: 10 pg/m3
    Log Relative Rate Estimate (p-value):
    Vienna
    Male: 2 day lag = 4.217 (0.030)
    Association with tidal lung function:
    P = -1.067 (p-value = 0.241)
    Notes: Effect parameters with
    significant coefficients for respiratory
    health included: male sex, allergy,
    asthma in family, and traffic for Vienna
    and age, allergy, asthma in family, and
    passive smoking for the rural area.
    Effect parameters with significant
    coefficients for log asthma score were
    allergy, asthma in family, and rain for
    Vienna and allergy, asthma in family,
    and passive smoking for the rural area.
    Reference: Oftedal et al. (2003,
    0556231
    Period of Study: 1995-2000
    Location: Drammen, Norway
    Hospital Admissions
    Outcome: All Respiratory (460-517)
    Age Groups: All
    Study Design: Time-series
    N: ~4,458 admissions
    Statistical Analyses: Poisson
    regression, GAM w/ stringent
    convergence criteria
    Covariates: Temperature, humidity,
    influenza epidemics, summer and
    Christmas vacation
    Season: All
    Dose-response Investigated? Yes
    Statistical Package: S-Plus
    Lags Considered: 2-3
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (SD): 16.8 pg/m3, (10.2) 1994-
    1997
    16.5 pg/m3, (10.3)1998-2000
    16.6,  pg/m3 (10.2) total period
    PM Component: Benzene,
    formaldehyde, toluene
    Monitoring Stations: NR
    Notes: Copollutant (correlation):
    Correlation between pollutants ranged
    from -0.47-0.78 with the exception of
    the VOCs studied
    Notes: Benzene, formaldehyde and
    toluene also evaluated
    PM Increment: IQr=11.04
    RR Estimate
    1.035 [0.990, 1.083] 1994-1997
    0.992 [0.948, 1.037] 1998-2000
    1.021 [0.990, 1.053] 1994-2000
    2 Pollutant Model
    PM10w/benzene: 1.01 (0.978,1.043)
    December 2009
                                    E-247
    

    -------
               Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95%  Cl)
    Reference: Peel et al. (2005, 0563051
    Period of Study: Jan 1993-Aug 2000
    Location: Atlanta, Georgia
    ED visits
    Outcome: Asthma (493, 786.09)
    COPD(491,492, 496)
    URI (460-466, 477)
    Pneumonia (480-486)
    Age Groups: All ages. Secondary
    analyses conducted by age group: 0-1,
    2-18, >18
    Study Design: Time series
    N: 31 hospitals
    Statistical Analyses: Poisson GEE for
    URI, asthma and all RD
    Poisson GLM for pneumonia and
    COPD)
    Covariates: Avg temperature and dew
    point, pollen counts
    Season: All (secondary analyses of
    warm season)
    Dose-response Investigated? Yes
    Statistical Package: SAS 8.3, S-Plus
    2000
    Lags Considered: 0-7 day, 3 day ma,
    0-13 days unconstrained distributed lag
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD): 27.9 (12.3) pg/m3
    Percentiles: 10th:  13.2
    90th: 44.7
    Monitoring Stations:
    "Several"
    Copollutant (correlation):
    8h03:r = 0.59
    1 hN02:r = 0.49
    1 hCO:r = 0.47
    1hS02:r = 0.20
    24-h PM25: 0.84
    24hPM10.25:r = 0.59
    24hUF:r = -0.13
    Components: r ranged from 0.42-0.74
    PM Increment: PMi0:10 pg/m
    RR Estimate [Lower Cl, Upper Cl]
    All Respiratory Outcomes:
    1.013(1.004-1.021), 3 day ma
    URI:
    1.014 (1.004-1.025), 3 day ma
    1.073(1.048-1.099), 14-day dist. lag
    Asthma:
    1.009(0.996-1.022), 3 day ma
    1.099(1.065-1.135), 14-day dist. lag:
    Pediatric Asthma 2-18yrs):
    1.016(0.998-1.034)
    Pneumonia:
    1.011 (0.996-1.027), 3 day ma
    1.087(1.044-1.132), 14-day dist. lag
    COPD:
    1.018(0.994-1.043), 3 day ma
    1.092(1.023-1.165), 14-day dist. lag
    Notes: RRs obtained using AQS 1993-
    2000, AQS 1998-2000 and ARIES data
    compared. Infant (0-1 y) and pediatric
    (2-18 y) asthma was associated more
    strongly with PMi0, PM25 and OC than
    adult asthma.
    Reference: Ren et al.
    (2006, 0928241
    Period of Study: Jan 1996-Dec 2001
    Location: Brisbane, Australia
    
    
    
    
    
    
    
    
    Hospital Admissions
    Outcome (ICD-9): Respiratory
    diseases (460-519) excluding influenza
    (487.0-487.8)
    Age Groups: NR
    Study Design: Time series
    N:NR
    Statistical Analyses: GAM
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (min-max): 15.84 (2.5-60)
    Monitoring Stations: 1
    Copollutant: NR
    
    
    PM Increment: NR
    Coefficient Estimates:
    Respiratory Hospital Admissions
    Same day: -0.004296
    1-day lag: -0.002474
    2-day lag: -0.004229
    *all statistically significant
                                       Covariates: Day of week, relative
                                       humidity, influenza outbreaks
                                       Season: NR
                                       Dose-response Investigated? Yes
                                       Statistical Package: S-Plus
                                       Lags Considered: 0, 1, and 2 days
                                                                          Respiratory Emergency Visits
                                                                          Same day: -0.000887
                                                                          1-day lag: -0.004209
                                                                          2-day lag: -0.003440
                                                                          Notes: Relative risks were provided in
                                                                          graphical form (Fig 3)
    Reference: Sauerzapfetal. (2009,
    1800821
    Period of Study: Mar 2006-Mar 2007
    Location: Norfolk, UK
    Outcome: COPD
    Study Design: Case-Crossover
    Covariates: Environmental factors and
    Influenza
    Statistical Analysis: Logistic
    regression
    Statistical Package: SPSS 14
    Age Groups: >18yr
    N: 1050 adult COPD admissions
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD) Unit:
    Control: 19.87 (8.51) pg/m3
    Case: 20.47 (9.27) pg/m3
    Range (Min, Max):
    Control: 9.77-34.27
    Case: 10.04-35.03
    Copollutant (correlation): NR
    Increment: 10|jg/m
    Odds Ratio (96% Cl)
    Lag 0-7, unadjusted: 1.079 (0.980-
    1.188)
    Lag 0-8, adjusted: 1.101 (0.988-1.226)
    Lag 1-8, unadjusted: 1.056 (0.961-
    1.161)
    Lag 1-8, adjusted: 1.054 (0.949-1.170)
    December 2009
                                   E-248
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Sinclair and Tolsma (2004,
    0886961
    Period of Study: 25 Months
    Location: Atlanta, Georgia
    Outpatient Visits
    Outcome: Asthma (493)
    URI(460, 461,462, 463, 464, 465, 466,
    477)
    LRI (466.1,480, 481,482, 483, 484,
    485, 486).
    Age Groups: < = 18 yr, 18+ yr (asthma)
    All ages (URI//LRI)
    Study Design: Times series
    N: 25 mo
    260,000-275,000 health plan members
    (Aug 1998-Aug 2000)
    Statistical Analyses: Poisson GLM
    Covariates: Season, Day of week,
    Federal Holidays, Study Months
    Season: NR
    Dose-response Investigated?: No
    Statistical Package: SAS
    Lags Considered: Three 3-day ma (0-
    2, 2-5, 6-8)
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD): PM,0 mass-29.03 pg/m3
    (11.61)
    Monitoring Stations: 1
    Notes: Copollutant: NR
    PM Increment: 11.61 (1 SD)
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Child Asthma: 1.049(3), lag 3-5 day
    LRI: 1.074(3), 3-5 day lag
    Notes: Numerical findings for significant
    results only presented in manuscript.
    Results for all lags presented
    graphically for each outcome (asthma,
    URI, and LRI).
    Reference: Slaughter et al. (2005,
    0738541
    Period of Study: Jan 1995-Jun 2001
    Location: Spokane, WA
    Hospital Admissions and ED visits
    Outcome: All respiratory (460-519)
    Asthma (493)
    COPD (491,492, 494,496)
    Pneumonia (480-487)
    Acute URI not including colds and
    sinusitis (464, 466, 490)
    Age Groups: All, 15+ yr for COPD
    Study Design: Time series
    N: 2373 visit records
    Statistical Analyses: Poisson
    regression, GLM with natural splines.
    For comparison also used GAM with
    smoothing splines and default
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Range (90% of concentrations): 7.9-
    41.9|jg/m3
    Monitoring Stations:
    1
    Notes: Copollutant (correlation):
    PM10
    PM1 r = 0.50
    PM25r = 0.62
                                                                          CO r = 0.32
                                                                          Tern peraturer = 0.11
    PM Increment: 25 pg/m
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    ER visits -PM10
    All Respiratory
    Lag 1:1.01
    Lag 2: 1.01
               0.99, 1.04]
               0.98,
                                                                                                                             1.04]
                                                                                                                             1.03]
                                                                                                              Lag 3: 1.02 [0.99, 1.04]
                                                                                                              Acute Asthma
                                                                                                              Lag 1:1.03 [0.98, 1.07]
                                                                                                              Lag 2: 1.01 [0.96, 1.05]
                                                                                                              Lag 3: 1.00 [0.95, 1.04]
                                                                                                              COPD (adult)
                                                                                                              Lag 1:1.00 [0.93, 1.07]
                                                                                                              Lag 2: 0.99
                                                                                                              Lag 3:1.02
                                                  0.92, 1.0
                                                  0.95, 1.0
                                       Hospital Admissions - PIvl-;
                                       All Respiratory
    uui ivci yci i^c ui ILCI la.
    Covariates: Season, temperature,
    relative humidity, day of week
    Season: All
    Dose-response Investigated?: No
    Statistical Package: SAS, SPLUS
    Lags Considered: 1 -3 day
    
    Lag 1:0.99
    Lag 2: 0.99
    0.95,
    0.96,
    Lag 3: 1.00 [0.97,
    Asthma
    Lag 1:1. 03
    Lag 2: 1.01
    Lag 3: 1.00
    COPD (adu
    Lag 1:0.98
    Lag 2: 1.03
    Lag 3: 1.02
    0.95,
    0.94,
    0.92,
    t)
    0.90,
    0.96,
    0.94,
    1.02
    1.02
    1.03]
    1.12]
    1.10]
    1.09]
    1.07]
    1.11]
    1.09]
    December 2009
                                    E-249
    

    -------
                Reference
           Design & Methods
            Concentrations1
                                           Effect Estimates (95%  Cl)
    Reference: Sun et al. (2006, 0907681
    Period of Study: Jan 2004-Dec 2004
    Location: Taichung, Taiwan (Central
    Taiwan)
    ED visits
    Outcome: Asthma (493.xx)
    Age Groups: <55, <16,16-55 yr
    Study Design: Cross-sectional
    N:NR
    All diagnoses for all patients at 4
    medical centers
    Statistical Analyses: Pearson's
    correlations, multiple correlation
    coefficients from regression analyses.
    Covariates: Only copollutants
    considered
    Dose-response Investigated?  No
    Statistical Package: SPSS
    Lags Considered: None
    Pollutant: PM,0                       Children ED Visits
    Averaging Time: Monthly avg for 2004   r = 0.626
                                        P = 0.015
                                        Adult ED Visits
                                        r = 0.384
                                        P = 0.109
    Mean(SD):~60.3|jg/m3
    (estimated from Fig)*
                                                                           Range (Min, Max): (-35, 80)
                                                                           Monitoring Stations: 11
                                                                           Copollutant: NR
    Reference: Szyszkowicz (2007,
    Period of Study: Jan 1992-Mar 2002
    Location: Edmonton, Canada
    Outcome: ED visits for asthma (ICD-
    (493)
    Study Design: Time-series
    Covariates: Temperature, relative
    humidity
    Statistical Analysis: Poisson
    regression
    Age Groups: All
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD) Unit: 22.6 (13.1) pg/m3
    Median, IQR: 19.4,  15.0
    Copollutant (correlation): NR
                                        Increment: IQR
                                        Percent Relative Risk (96% Cl)
                                        "Only statistically significant results are
                                        presented in the paper*
                                        No lag, > 10 yr
                                        Apr-Sep, All: 3.7 (1.5-6.0)
                                        Apr-Sep, Female: 4.5 (1.8-7.3)
                                        Apr-Sep, Male: 3.3 (0.1-6.7)
                                        2 day lag,  <10yr
                                        Year round, All: 2.7 (0.1-5.4)
                                        Apr-Sep, All: 6.3 (2.6-10.2)
                                        Apr-Sep, Male: 7.4 (3.1-11.9)
                                        2 day lag,  > 10 yr
                                        Apr-Sep, All: 2.4 (0.1-4.7)
                                        Apr-Sep, Female: 3.9 (1.1-6.7)
    Reference: Tecer et al, (2008, 1 80030) Outcome: ED visits for respiratory
    Period of Study: Dec 2004-Oct 2005 pr°b'emS ^ 47M7* 493)
    Study Design: Bidirectional Case-
    Location: Zonguldak, Turkey crossover
    Covariates: Daily meteorological
    parameters
    Statistical Analysis: Conditional
    logistic regression
    Statistical Package: Stata
    Age Groups: 0-1 4 yr
    Pollutant: PM,0
    Averaging Time: NR
    Mean, Unit: 53.3 pg/m3
    Range (Min, Max): 12-237.5
    Copollutant (correlation):
    PM25/PM10
    Mean: 0.56
    Range: 0.17-0.88
    Increment:
    10|jg/m3
    Odds Ratio (96% Cl)
    Asthma
    Lag 0:1. 14 (1.03-1. 26)
    Lag 1:0.92
    Lag 2: 0.92
    Lag 3: 1.01
    0.83-1.02)
    0.81-1.03)
    0.92-1.11)
    Lag 4: 1.16 (1.06-1. 26)
    Allergic Rhinitis with Asthma
    Lag 0:1. 07
    Lag 1:0.96
    Lag 2: 0.93
    Lag 3: 0.96
    1.01-1.13)
    0.91-1.02)
    0.88-0.99)
    0.90-1.02)
    Lag 4: 1.08 (1.02-1. 14)
    Allergic Rhinitis
    Lag 0:1. 06 (0.99-1. 13)
    
    
    
    
    Lag 1:1. 08
    Lag 2: 0.92
    1.01-1.16)
    0.87-0.99)
    Lag 3: 0.97 (0.92-1. 03)
    Lag 4: 1.09 (1.03-1. 16)
    Upper Respiratory Disease
    
    
    
    
    
    
    Lag 0: 0.88
    Lag 1:1. 17
    Lag 2: 1.00
    0.68-1.14)
    0.91-1.51)
    0.76-1.31)
    Lag 3: 0.95 (0.76-1. 19)
    Lag 4: 1.15 (0.97-1. 35)
    Lower Respiratory Disease
    Lag 0:1. 01 (0.86-1. 19)
    
    
    
    
    Lag 1:1. 04
    Lag 2: 1.04
    0.88-1.23)
    0.92-1.18)
    Lag 3: 1.23 (1.07-1. 41)
    Lag 4: 0.99 (0.90-1. 08)
    December 2009
                                    E-250
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Tolbert et al. (2007,
    0903161
    Period of Study: 1993-2004
    
    Location: Atlanta Metropolitan area,
    Georgia
    Hospital Admissions/ED visits
    
    Outcome (ICD-9):
    
    Combined RD group, including:
    Asthma (493, 786.07, 786.09), COPD
    (491, 492, 496), URI (460-465, 460.0,
    477), pneumonia (480-486), and
    bronchiolitis (466.1,466.11, and
    466.19))
    
    Age Groups Analyzed: All
    
    Study Design: Time series
    
    N: 10,234,490 ER visits (283,360 and
    1,072,429 visits included in the CVD
    and RD groups, respectively)
    
    Statistical Analyses: Poisson
    generalized linear models
    
    Covariates: Long-term temporal trends,
    season (for RD outcome), temperature,
    dew point, days of week, federal
    holidays, hospital entry and exit
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical package: SAS version 9.1
    
    Lags Considered:  3-day ma(lag 0 -2)
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (median
    
    IQR, range, 10th-90th percentiles):
    26.6 (24.8
    
    17.5-33.8
    
    0.5-98.4
    
    12.3-42.8)
    
    Monitoring Stations: NR
    Copollutant (correlation):
    03:r = 0.59
    N02:r = 0.53
    CO: r = 0.51
    S02:r = 0.21
    Coarse PM:r = 0.67
    PM25:r = 0.84
    PM25S04:r = 0.69
    PM25EC:r = 0.61
    PM25OC:r = 0.65
    PM25TC:r = 0.67
    PM25 water-sol metals: r = 0.73
    OHC:r = 0.53
    PM Increment: 16.30 pg/rri (IQR)
    
    Risk ratio [96% Cl]:
    
    Single pollutant models:
    
    RD: 1.015 (1.006-1.024)
    
    Notes: Results of selected multi-
    pollutant models for respiratory disease
    are presented in Fig 2.
    
    Fig 2: PM10 adjusted for CO, 03, N02,
    or N02/03 (nonwinter months only)
    
    Summary of results: PMi0 remained
    predictive of RD in non-winter months
    after adjustment for pollutants.
    Reference: Tsai et al. (2006, 0897681
    
    Period of Study: 1996-2003
    
    Location: Kaohsiung City, Taiwan
    Outcome: Asthma (493)
    
    Age Groups: All (universal health care
    covers >96% of the population)
    
    Study Design: Case crossover
    
    N: 17,682 admissions
    
    63 hospitals
    
    Statistical Analyses: Conditional
    Logistic Regression
    
    Covariates: Temperature, humidity
    
    Season: Warm and cool seasons
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: 0-2 day cumulative
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 76.62 pg/m3 (NR)
    
    Percentiles: 25th: 41.73
    
    SOth(Median): 74.40
    
    75th: 104.01
    
    Range (Min, Max): (16.70, 232.00)
    
    Monitoring Stations: 6
    
    Copollutant: NR
    PM Increment: 62.28 pg/m
    
    OR Estimate [Lower Cl, Upper Cl]
                                                                                                             Single-pollutant model, 0-2 day
                                                                                                             cumulative lag
                                                                                                             >25oC: 1.302 [1.155, 1.467]
                                                                                                             <25oC: 1.556 [1.398, 1.371]
                                                                                                             Two-pollutant models, 0-2 day
                                                                                                             cumulative lag
                                                                                                             PM,oW/S02
                                                                                                             >25oC: 1.305 [1.156, 1.473]
                                                                                                             <25oC: 1.540 [1.374, 1.727]
                                                                                                             PM10w/03
                                                                                                             >25oC: 0.985 [0.842, 1.152]
                                                                                                             <25oC: 1.581 [1.402, 1.783]
                                                                                                             PM,0w/N02
                                                                                                             >25oC: 1.237 [1.052, 1.455]
                                                                                                             <25oC: 1.009 [0.875, 1.163]
                                                                                                             PM,oW/CO
                                                                                                             >25oC: 1.156 [1.012, 1.320]
                                                                                                             <25oC: 1.300 [1.134, 1.490]
    December 2009
                                   E-251
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ulirsch et al. (2007,
    0913321
    
    Period of Study: Nov 1994-Mar 2000
    
    Location: Pocatello,  Idaho
    
    Chubbuck, Idaho
    Outcome: Respiratory Disease (460-
    499, 509-519)
    
    Reactive Airway Disease (786.09)
    
    Age Groups: All age groups
    
    Study Design: Time series
    
    N: 39,347 visits (TS1)
    
    29,513 visits (TS2)
    
    Statistical Analyses: Poisson
    regression, GLM. Sensitivity Analyses
    
    Covariates: Time, Temperature,
    Relative Humidity Influenza
    
    Season: Warm/Cool
    
    Dose-response Investigated? No
    
    Statistical Package: S-Plus
    
    Lags Considered: 0-4 day lags
    
    Notes: Time series (TS) 1 includes HA,
    ED and urgent care visits. TS 2 includes
    family practice data available after 1997
    Pollutant: PM,0
    
    Averaging Time: NR
    
    Mean (SD):TS1: 24.2 pg/m3(NR)
    
    10th: 10.5
    
    90th: 40.7
    
    TS2: 23.2
    
    10th: 10.0
    
    90th: 37.4
    
    Range (Min, Max):
    
    TS1: (3.0, 183.0)
    
    TS2: (3.0, 183.0)
    
    Monitoring Stations:  4
    
    Notes: Copollutant (correlation):
    PM10 w/ N02: r = 0.47. PM10 with other
    copollutants weakly correlated.
    PM Increment: Single Pollutant
    Models, TS1: 24.4 pg/m3
    
    Single Pollutant Models: TS2:
    23.2 pg/m3
    
    Multipollutant Models: TS1/TS2:
    50 pg/m3
    Mean Percentage Change, lag 0
    TS1: Single Pollutant
                                                                                                                All-age (all yr): 4.0
                     1.4,6.7]
                                                                                                                18-64: 3.4 [0.2, 6.7
                                                                                                                0-17: 4.3 [-0.1, 8.9]
                                                                                                                65+: 5.6 [-1.4, 13.1]
                                                                                                                0-17/65+:5.5[1.4, 9.6]
                                                                                                                All age (Cool season): 4.3 [1.3, 7.5]
                                                                                                                All age (Warm season): 6.7 [-0.8,14.8]
                                                                                                                TS2: Single Pollutant
                                                                                                                All-age: 3.3 [0.3, 6.3]
                                                                                                                18-64: 3.3 [-0.4, 7.0]
                                                                                                                0-17: 5.0 [0.1, 10.1
                                                                                                                65+: 6.9 [-0.4, 14.7
                                                                                                                Multipollutant (PM10 + S02)
                                                                                                                All-age (all yr): TS1 10.8
                                                                                                                TS2 17.5
                                                                                                                18-64: TS1 8.0
                                                                                                                TS29.1
                                                                                                                0-17: TS1 10.8
                                                                                                                TS2 32.7
                                                                                                                65+:TS18.7
                                                                                                                TS231.3
                                                                                                                0-17/65+:TS1  14.2
                                                                                                                TS2 25.3
                                                                                                                All age (Cool season) TS1 11.9
                                                                                                                Multipollutant (PM10 + N02)
                                                                                                                All-age (all yr)TS1:TS2 16.3
                                                                                                                18-64: TS1 9.3
                                                                                                                TS2 17.3
                                                                                                                0-17: TS1 4.6
                                                                                                                TS2 18.7
                                                                                                                65+:TS1 12.4
                                                                                                                TS2 32.7
                                                                                                                0-17/65+:TS19.5
                                                                                                                32.7
                                                                                                                All age (Cool season): TS1 11.1
                                                                                                                TS2 16.8
                                                                                                                Notes: Results from multipollutant
                                                                                                                model with PMi0, S02 and N02 also
                                                                                                                available.
    Reference: Vegni and Ros (2004,
    0874481
    Period of Study: Sep 2001-Sep 2002
    
    Location: Milan area, Italy
    Hospital Admissions
    
    Outcome (ICD-9): Respiratory, non-
    infectious admissions (ICD: NR)
    
    Age Groups: NR
    
    Study Design: Time series
    
    N: 9881 admissions
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Temperature, wind velocity,
    relative humidity, week day, holidays
    
    Season: Spring, summer, fall, winter
    
    Dose-response Investigated? No
    
    Statistical Package: STATAv. 5
    
    Lags Considered: 0, 1, and 2 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (6th-96th percentile):
    
    Overall: 41.5 (13-98) SD = 28.2
    Spring: 29.0 (10-51) SD=12.6
    Summer: 24.8 (10-40) SD = 9.9
    Fall: 51.8 (21-114) SD = 27.1
    Winter: 64.1(20-135) SD = 35.7
    
    Monitoring Stations: 1
    
    Copollutant: NR
    PM Increment: Increase from 5th-95th
    percentile
    
    Spring: 85 pg/m3
    
    summer: 30 pg/m3
    
    Fall: 93 pg/m3
    
    Wnter: 115 pg/m3
    
    RR Estimate [Cl]:
    
    Overall: 1.10 [0.83,1.46]
    
    Adjusted: 0.97 [0.67,1.41]
    
    Notes: 1-day and 2-day lags show
    similar results, with no association
    between PM10 and daily hospital
    admissions
    December 2009
                                    E-252
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Vigotti et al. (2007, 0907111  ED Visits
    Period of Study: Jan 2000-Dec 2000
    Location: Pisa, Italy
    Outcome: Asthmatic attack (493), dry
    cough (468), acute bronchitis (466)
                                       Age Groups: <10 yr; 65+ yr
                                       Study Design: Time series
                                       N: 966 Emergency room visits
                                       Statistical Analyses: Poisson
                                       regression, GAM, LOESS smoothers,
                                       stringent criteria
                                       Covariates: Temperature,  humidity,
                                       relative humidity, day of study, rainfall,
                                       influenza, day of-the-wk, holidays, time
                                       trend
                                       Season: All yr
                                       Dose-response Investigated? No
                                       Statistical Package: NR
                                       Lags Considered: 0-5 days
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): 35.4 (15.8) pg/m3
    Percentiles: 25th: NR
    50th(Median):31.6
    75th: NR
    Range (Min, Max): (9.5,100.1)
    Monitoring Stations:
    2
    Copollutant (correlation):
    PM10:
    N02r = 0.58
    CO r = 0.70
    PM Increment: 10 pg/m
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    <10y:10%[2.3,18.2]
    Iag1
    65+: 8.5% [1.5, 16.1]
    lag 2
    Reference: Xirasagar et al. (2006,
    0932671
    Period of Study: 1998-2001
    Location: Taiwan
    Hospital Admission/ED:
    Outcome: Asthma or Asthmatic
    Bronchitis (493)
    Age Groups: <2 yr old, 2~5 yr old,
    6-14 yr old
    Study Design:
    N: 27, 275 pediatric hospitalizations
    Statistical Analyses: ARIMA Modeling
    Spearman's Correlations
    Covariates: Season, ambient temp.,
    rel. humidity, atmospheric pressure,
    rainfall, h of sunshine
    Season: Spring: Feb-Apr
    Summer: May-Jul
    Fall:Aug-Oct
    Winter: Nov-Jan
    Dose-response Investigated? No
    Statistical Package: EViews 4
    Lags Considered: NR
    Pollutant: PM,0
    Averaging Time: Monthly means
    Mean (SD): 24.4 pg/m3 (NR)
     Percentiles: NR
    Range (Min, Max): NR
    PM Component: NR
    Monitoring Stations: 44 air quality
    monitoring banks. 23 weather
    observatories
    Notes: Copollutant (correlation):
    <2 yr old: r = 0.315
    2-5 yr old: r = 0.589
    6-14 yr old: r = 0.493
    PM Increment: NR
    RR Estimate [Lower Cl, Upper Cl]
    lag: NR
    AR Estimate [Lower Cl, Upper Cl]
    lag: NR
    Notes: Plot of monthly asthma
    admission rates per 100,000 population
    by age group
    Plot of mean monthly concentration
    trends of criteria air pollutants
    Mean monthly trends of climatic factors
    Other Outcomes Assessed? NR
    Other Exposures Assessed?
    Seasonal ity
    December 2009
                                   E-253
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Wong et al., (2002,
    0232321
    
    Period of Study: 1995-1997 (Hong
    Kong) and 1992-1994 (London)
    
    Location: Hong Kong and London
    Hospital Admissions
    
    Outcome (ICD- NR): Asthma (493) for
    ages 15-64 and respiratory disease
    (460-519) for ages 65+
    
    Age Groups: 15-64, 65+
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Poisson
    regression, GAM
    
    Covariates: Temperature, humidity, and
    influenza
    
    Season: Warm (Apr-Sep) and cool
    (Oct-Mar)
    
    Dose-response Investigated? Yes
    
    Statistical Package: S-Plus
    
    Lags Considered: 0-3 days
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (min-max): Hong Kong: 51.i
    (14.1-163.8)30 = 25.0
    
    London: 28.5 (6.8-99.8)
    
    SD=13.7
    
    Monitoring Stations: NR
    Copollutant (correlation):
    Hong Kong
    N02:r = 0.82
    S02:r = 0.30
    03:r = 0.54
    London
    N02:r = 0.68
    S02:r = 0.64
    03:r = 0.17
    
    Other variables: Hong Kong
    Temp: r = -0.42
    Humidity: r = -0.53
    London
    Temp: r = 0.02
    Humidity: r = -0.05
    PM Increment: 10 pg/m
    
    ER Estimate [Cl]:
    Single-pollutant excess risk (mean lag
    0-1 day)
    Asthma-Hong Kong:-1.1  [-2.4,0.1]
    Asthma-London: 1.4 [-0.1,3.0]
    Respiratory Disease-Hong Kong:
    1.0 [0.5,1.5]
    Respiratory Disease-London:
    0.4 [-0.3,1.2]
    Warm season
    Asthma-Hong Kong: -1.0 [-2.8, 0.8]
    Asthma-London: 0.6 [-1.9,3.1]
    Respiratory Disease-Hong Kong:
    0.8 [0.1,1.4]
    Respiratory Disease-London:
    1.8 [0.5,3.1]
    Cool  season
    Asthma-Hong Kong: -1.2 [-2.8,0.4]
    Asthma-London: 1.6 [-0.3,3.6]
    Respiratory Disease-Hong Kong:
    1.2 [0.6,1.9]
    Respiratory Disease-London:
    -0.5 [-1.5,0.5]
    Notes: RRs are shown graphically in
    Fig 1 and 2. Exposure response curves
    are provided in  Fig 5 of the article
    Reference: Wong et al. (2006, 0932661
    Period of Study: 2000-2002
    Location: Hong Kong (8 districts)
    
    
    
    
    General Practitioner Visits
    Outcome (ICPC-2): Respiratory
    diseases/symptoms: upper respiratory
    tract infections (URTI), lower respiratory
    infections, influenza, asthma, COPD,
    allergic rhinitis, cough, and other
    respiratory diseases
    Age Groups: All ages
    Study Design: Time series
    N: 269,579 visits
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (min-max): Ranged from 43.4-
    56.9 (dependent on location)
    Monitoring Stations: 1 per district
    Copollutant (correlation):
    PM25:r = 0.94
    03:r = 0.40
    S02:r = 0.28
    PM Increment: 10 pg/m3
    RR Estimate [C I]:
    Overall URTI
    1.020 [1.016,1.025]
    Overall Non-UTRI
    1.025 [1.018,1.032]
    Notes: RRs are also reported for each
    individual general practitioner yielding
    similar results
                                       Statistical Analyses: GAM, Poisson
                                       regression
    
                                       Covariates: Season, day of the week,
                                       climate
    
                                       Season: NR
    
                                       Dose-response Investigated? No
    
                                       Statistical Package: S-Plus
    
                                       Lags Considered: 0-3 days
    December 2009
                                    E-254
    

    -------
               Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Yang et al. (2007, 0928471   Hospital Admission/ED:
    Period of Study: 1996-2003
    Location: Taipei, Taiwan
    Outcome: Asthma (493)
    Age Groups: All ages
    Study Design: Case-crossover
    N: 25,602 asthma hospital admissions
    Statistical Analyses: NR
    Covariates: Temperature, humidity, day
    of-the-wk, seasonality, long term trends
    Season: All yr
    Dose-response Investigated? No
    Statistical Package:  SAS
    Lags Considered: 0-2
    Pollutant: PM,0
    Averaging Time: NR
    Mean (SD): 48.99 pg/m3
    Percentiles: 26th: 32.64
    60th(Median):44.13
    76th: 59.05
    Range (Min, Max): (14.44, 234.91)
    PM Component: NR
    Monitoring Stations:
    6 Stations
    Notes: Copollutant: NR
    PM Increment: 26.41 pg/m
    OR Estimate [Lower Cl, Upper Cl]
    lag:
    Asthma
    Single-Pollutant Model: Temperature
    >25°C:1.046[0.971, 1.128]
    Temperature <25° C:
    1.048(1.011,1.251]
    Two-Pollutant Model: Adjusted for S02:
    >25° 01.006(0.920, 1.099]
    <25° 01.088(1.040, 1.138]
    Adjusted for N02:
    >25° 00.800(0.717, 0.892]
    <25° 00.982(0.937, 1.029]
    Adjusted for CO:
    >25° 00.920(0.844, 1.002]
    <25° 01.029(0.984, 1.076]
    Adjusted for 03:
    >25° 01.038(0.950, 1.134]
    <25° 01.042(1.004, 1.081]
    AR Estimate [Lower Cl, Upper Cl]
    lag: NR
    Notes: Other Outcomes Assessed?
    NR
    Other Exposures Assessed? S02,
    N02, CO, 03
    Reference: Yang et al. (2007, 0928471   Hospital Admission
    Period of Study: 1996-2003
    Location: Taipei, Taiwan
    Outcome: COPD (490-192), (494),
    (496)
                                       Age Groups: All ages
                                       Study Design: Case-crossover
                                       N: 46,491 COPD admissions, 47
                                       hospitals
                                       Statistical Analyses: Conditional
                                       logistic regression
                                       Covariates: Wfeather, day of-the-wk,
                                       seasonality, long term trends
                                       Season: Warm/Cool
                                       Dose-response Investigated? No
                                       Statistical Package: SAS
                                       Lags Considered: 0-2  cumulative
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (SD): 48.99 pg/m3
    26th: 32.64
    60th(Median):44.13
    76th: 59.05
    Range (Min, Max):
    (14.44, 48.99)
    Monitoring Stations:
    6 Stations
    Notes: Copollutant: NR
    PM Increment: 26.41 pg/m
    OR Estimate [Lower Cl, Upper Cl]
    Single-Pollutant Model (0-2 day cum
    lag):
    Temperature >20° 0:1.133(1.098,
    1.168]
    Temperature <20° C: 1.035(0.994,
    1.077]
    Two-Pollutant Model:
    PM,0w/S02:
    >20° 0-1.180(1.139, 1.223]
    <20° 0-1.004(0.954, 1.057]
    PM,0w/N02:
    >20° 0-1.013(0.973, 1.055]
    <20° 0-1.074(1.022, 1.129]
    PM,oW/CO:
    >20° 0-1.061(1.023, 1.100]
    <20° 0-1.067(1.016, 1.120]
    PM10w/03:
    >20° 0-1.097(1.062, 1.133]
    <20° 0-1.036(0.996, 1.079]
    December 2009
                                   E-255
    

    -------
    Reference
    Reference: Yang et al. (2004, 0874881
    Period of Study: Jun 1995-Mar 1999
    Location: Vancouver area, British
    Columbia
    Design & Methods
    Hospital Admissions
    Outcome (ICD-9): Respiratory
    diseases (460-519), pneumonia only
    (480-486), asthma only (493)
    Age Groups: 0-3 yr
    Studv Desian: Case control
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24 h
    Mean (min-max):
    13.3(3.8-52.2)
    SD = 6.1
    Effect Estimates (95% Cl)
    PM Increment: 7.9 pg/m3 (IQR)
    OR Estimate [Cl]:
    Values NR
    Notes: Author states that ORs for PMi0
    increased with lag time up to 3 days for
    both sinale and multiole-Dollutant
                                       bidirectional case-crossover (BCC), and
                                       time series (TS)
                                       N: 1610 cases
                                       Statistical Analyses: Chi-square test,
                                       Logistic regression, GAM (time-series),
                                       GLM with parametric natural cubic
                                       splines
                                       Covariates: Gender, socioeconomic
                                       status, weekday, season, study yr,
                                       influenza epidemic month
                                       Season: Spring, summer, fall, winter
                                       Dose-response Investigated? No
                                       Statistical Package: SAS (Case
                                       control and BCC), S-Plus (TS)
                                       Lags Considered: 0-7 days
                                               Monitoring Stations: NR (data
                                               obtained from Greater Vancouver
                                               Regional District Air Quality Dept)
                                               Copollutant (correlation):
                                               PM25:r = 0.83
                                               PM10.2.5: r = 0.83
                                               CO: r = 0.46
                                               03:r = -0.08
                                               N02:r = 0.54
                                               SO,: r = 0.61
                                                                                                             models.
     All units expressed in pg/m  unless otherwise specified.
    Table E-13.    Short-term exposure-respiratory-ED/HA-PMi  25.
           Reference
          Design & Methods
         Concentrations'!
                Effect Estimates (95% Cl)
    Reference: Chen et al.
    (2005, 0875551
    Period of Study:
    Jun1995-Mar1999
    Location: Vancouver area,
    BC
    Hospital Admissions
    Outcome (ICD-9): Acute respiratory
    infections (460-466), upper
    respiratory tract infections (470-478),
    pneumonia and influenza (480-487),
    COPD and allied conditions (490-
    496), other respiratory diseases (500-
    519)
    Age Groups: >65 yr
    Study Design: Time series
    N: 12,869
    Statistical Analyses: GLM
    Covariates: Temp and relative
    humidity
    Season: NR
    Dose-response Investigated? No
    Statistical Package: S-Plus
    Lags Considered:  1,2,3,4,5,6,
    and 7-day avg
    Pollutant: PMi0.2.5 (fjg/m)
    Averaging Time: 24 h
    Mean (min-max):
    5.6(0.1-24.6)
    SD = 3.6
    Monitoring Stations: 13
    Copollutant (correlation):
    PM25:r = 0.38
    PM,o:r = 0.83
    COH:r = 0.63
    CO: r = 0.53
    03:r = -0.13
    N02:r = 0.54
    S02:r = 0.57
    Other variables:
    Mean temp: r = 0.13
    Rel humidity: r = -0.27
    PM Increment: 4.2 pg/m
    RR Estimate [Cl]:
    Adj for weather conditions
    Overall admission
    1-day avg: 1.03 [1.00,1.06]
    2-day avg: 1.05 [1.02,1.08]
    3-day avg: 1.06 [1.02,1.09]
    Adj for weather conditions and copollutants
    Overall admission
    1-day avg: 1.02 [0.98,1.06]
    2-day avg: 1.05 [1.01,1.10]
    3-day avg: 1.06 [1.02,1.11]
    Notes: RR's were also provided for lags 4-7 in Table 3,
    yielding similar results
    December 2009
                                            E-256
    

    -------
    Reference
    Reference: Fung et al. (2006,
    0897891
    
    Period of Study:
    Jun1995-Mar1999
    Location: Vancouver,
    Canada
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Halonen et al.
    (2009, 1803791
    
    Period of Study: 1998-2004
    Location: Helsinki, Finland
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Hospital Admission/ED: Hospital
    Admission
    
    Outcome: Respiratory diseases
    (460-519)
    Age Groups: Age >65
    Study Design: Time series
    N: 26,275 individuals admitted
    Statistical Analyses: Poisson
    regression (spline 12 knots), case-
    crossover (controls +17 days from
    case date), Dewanji and Moolgavkar
    (DM) method
    Covariates: Long-term trends, day-
    of-the-week effect, weather
    Season: All yr
    Dose-response Investigated? No
    Statistical Package: SPIus, R
    Lags Considered: 0-7 days
    
    
    
    Outcome: Hospital Admissions
    
    Age Groups: 65+ yr
    Study Design: Time series
    N:NR
    
    Statistical Analyses: Poisson, GAM
    Covariates: Temperature, humidity,
    influenza epidemics, high pollen
    episodes, holidays
    Dose-response Investigated? No
    Statistical Package: R
    
    Lags Considered: Lags 0-3 & 5-day
    (0-4) mean
    
    
    
    
    
    
    
    Concentrations!
    Pollutant: PM10.2.5 (|jg/m3)
    
    Averaging Time: 24-h avg
    Mean (SD)
    5.6(3.88) pg/m3
    Range (Min, Max):
    (-2.9, 27.07)
    Monitoring Stations:
    NR
    Notes: Copollutant
    (correlation):
    PM,0-2.5
    PM,0r = 0.83
    PM25 r = 0.34
    CO r = 0.51
    CoH r = 0.61
    03r = -0.11
    N02r = 0.52
    S02r = 0.57
    
    Pollutant: PM10.25
    
    Averaging Time: Daily
    Mean (SD): NR
    Min: 0.0
    
    26th percentile: 4.9
    60th percentile: 7.5
    76th percentile: 12.1
    Max: 101. 4
    Monitoring Stations: NR
    
    Copollutant:
    PMO.03, PM0.03-0.1,PM<0.1,
    PM<0.10.29, PM25, CO, N02
    Co-pollutant Correlation
    pM
    -------
           Reference
          Design & Methods
         Concentrations!
                Effect Estimates (95% Cl)
    Reference: Host et al. (2007,
    1558511
    Period of Study: 2000-2003
    Location: Six French cities:
    Le Havre, Lille, Marseille,
    Paris, Rouen, and Toulouse
    
    
    
    
    
    
    
    
    
    
    Outcome (ICD-10): Daily
    hospitalizations for all respiratory
    diseases (JOO-J99), respiratory
    infections (J10-J22).
    Age Groups: For all respiratory
    diseases: 0-14 yr, 15-64 yr, and 2
    65 yr
    For respiratory infections: All ages
    Study Design: Time series
    N: NR (Total population of cities:
    approximately 10 million)
    Statistical Analyses: Poisson
    regression
    Covariates: Seasons, days of the
    week, holidays, influenza epidemics,
    pollen counts, temperature, and
    temporal trends
    
    Pollutant: PM10.2.5
    Averaging Time: 24 h
    Mean ug/m3 (6th -96th
    percentile):
    Le Havre: 7.3 (2.5-14.0)
    Lille: 7.9 (2.2-13.7)
    Marseille: 11.0 (4.5-21.0)
    Paris: 8.3 (3.2-15.9)
    Rouen: 7.0 (3.0-12.5)
    Toulouse: 7.7 (3.0-15.0)
    Monitoring Stations:
    13 total: 1 in Toulouse
    4 in Paris
    
    2 each in other cities
    PM Increment: 10 pg/m3 , and an 18.8 pg/m3 increase
    (corresponding to an increase in pollutant levels between
    the lowest of the 5th percentiles and the highest of the 95th
    percentiles of the cities' distributions)
    ERR (excess relative risk) Estimate [Cl]: For all respiratory
    diseases (10 pg/m3 increase): 0-14 yr: 6.2% [0.4, 12.3]
    15-64yr:2.6%
    [-0.5, 5.8]
    > 65 yr: 1.9% [-1.9, 5.9]
    For all respiratory diseases (18.8 pg/m3 increase): 0-14 yr:
    12.0 [0.8, 24.3]
    15-64 yr: 5.0 [-0.9, 11.1]
    > 65 yr: 3.7 [-3.6, 11.4]
    For respiratory infections (10 pg/m3): All ages: 4.4% [0.9,
    Q ni
    O.UJ
                               Dose-response Investigated: No
                               Statistical Package: MGCV package
                               in R software (R 2.1.1)
                               Lags Considered: Avg of 0-1  days
                                      Copollutant (correlation):
                                      PM25: Overall: r>0.6
                                      Ranged between r = 0.28 and
                                      r = 0.73 across the six cities.
                                 For respiratory infections (18 pg/m ): All ages:
                                 15.5]
                                                                                                                  .7,
    Reference: Lin et al. (2005,
    0878281
    Period of Study: 1998-2001
    Location: Toronto, North
    York, East York, Etobicoke,
    Scarborough, and York
    (Canada)
    Hospital Admissions
    Outcome (ICD-9): Respiratory
    infections including laryngitis,
    tracheitis, bronchitis, bronchiolitis,
    pneumonia, and influenza (464, 466,
    480-487)
    Age Groups: 0-14 yr
    Study Design: Bidirectional case-
    crossover
    N: 6782 respiratory infection
    hospitalizations
    Statistical Analyses: Conditional
    logistic regression (Cox proportional
    hazards model)
    Covariates: Daily mean temp and
    dew point temp
    Season: NR
    Dose-response Investigated? No
    Statistical Package: SAS 8.2
    PHREG procedure
    Lags Considered: 1- to 7-day avg
    Pollutant: PM10.25 (pg/m3)
    Averaging Time: 24 h
    Mean (min-max):
    10.86 (0-45.00)
    SD = 5.37
    Monitoring Stations: 4
    Copollutant (correlation):
    PM25:r = 0.33
    PM10:r = 0.76
    CO: r = 0.06
    S02:r =  0.29
    N02:r =  0.40
    03:r = 0.30
    PM Increment: 6.5 pg/m3
    OR Estimate [Cl]:
    Adjusted for weather
    4-day avg: 1.16 [1.07,1.26]
    6-day avg: 1.21 [1.10,1.32]
    Adj for weather and other gaseous pollutants
    4-day avg: 1.13 [1.03,1.23]
    6-day avg: 1.17 [1.06,1.29]
    Notes: OR's were also categorized into "Boys" and "Girls,"
    yielding similar results
    December 2009
                                             E-258
    

    -------
    Reference
    Reference: Lin et al. (2002,
    0260671
    
    Period of Study:
    Jan 1981-Dec 1993
    Location: Toronto
    
    
    
    
    
    
    
    
    
    
    
    Reference: Peel et al. (2005,
    ncc*3nc\
    UbbJUb)
    Period of Study:
    Jan 1993-Aug 2000
    Location: Atlanta, Georgia
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Hospital Admissions
    
    Outcome (ICD-9): Asthma (493)
    Age Groups: 6-12 yr
    Study Design: Uni- and bi-directional
    case-crossover (UCC, BCC) and
    time-series (TS)
    
    N: 7,319 asthma admissions
    Statistical Analyses: Conditional
    logistic regression, GAM
    Covariates: Maximum and minimum
    temp, avg relative humidity
    Season: Apr-Sep, Oct-Mar
    
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: 1- to 7-day avg
    
    
    
    ED visits
    Outcome: Asthma (493, 786.09)
    COPD(491,492, 496)
    URI (460-466, 477)
    Pneumonia (480-486)
    Age Groups: All ages. Secondary
    analyses conducted by age group: 0-
    1,2-18, >18
    Study Design: Time series
    N: 31 hospitals
    Statistical Analyses: Poisson GEE
    for URI, asthma and all RD
    Poisson GLM for pneumonia and
    COPD)
    
    Covariates: Avg temperature and
    dew point, pollen counts
    Season: All (secondary analyses of
    warm season)
    
    Dose-response Investigated? Yes
    Statistical Package: SAS 8.3
    S-Plus 2000
    Lags Considered: 0-7 days, 3-day
    ma, 0-13 days unconstrained
    distributed lag
    Concentrations!
    Pollutant: PM10.2.5 (|jg/m3)
    
    Averaging Time: 6 days
    (predicted daily values)
    Mean (min-max):
    12.17(0-68.00)
    SD = 7.55
    Monitoring Stations: 1
    Copollutant (correlation):
    PM25; r = 0.44
    PM10:r = 0.83
    CO: r = 0.17
    
    S02: r = 0.28
    N02:r = 0.38
    03:r = 0.56
    
    
    
    Pollutant: PMi0.25 (pg/rn3)
    Averaging Time: 24 h avg
    Mean (SD): 9.7 (4.7)
    Percentiles: 10th: 4.4
    90th: 16.2
    Monitoring Stations:
    "Several"
    Copollutant (correlation):
    24hPM,0:r = 0.59
    8h03:r = 0.35
    1hN02:r = 0.46
    
    1 hCO:r = 0.32
    
    1 hS02:r = 0.21
    24hPM25:r = 0.43
    
    Components: r ranged from
    0.23-0.51
    
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 8.4 pg/m3
    
    RR Estimate [Cl]:
    Adj for weather and gaseous pollutants
    BCC 5-day avg: 1.14 [1.01, 1.28]
    BCC 6-day avg: 1.17 [1.03,1. 33]
    TS 5-day avg: 1.14 [1.05,1.23]
    TS 6-day avg: 1.15 [1.06,1.25]
    Boys-adj for weather
    UCC 1-day avg: 1.08 1.01,1.16
    UCC 2-day avg: 1.08 0.99,1. 17:
    BCC 1-day avg: 1.06 1.00,1.14
    BCC 2-day avg: 1.06 0.98,1. 14:
    TS 1-day avg: 1.08 [1.03,1. 12]
    TS 2-day avg: 1.07 [1.01, 1.13]
    Girls-adj for weather
    UCC 1-day avg: 1.07 0.97,1.18
    UCC 2-day avg: 1.1 6 1.03,1.3f
    BCC 1-day avg: 0.98 0.90,1.07'
    BCC 2-day avg: 1.05 0.94,1.16
    TS 1-day avg: 1.00 [0.94,1.06
    TS 2-day avg: 1.05 [0.98,1. 13
    Notes: The author also provides RR using UCC, BCC, and
    TS analysis for female and male groups for day 3-7, yielding
    similar results
    PM Increment: 5
    RR Estimate [Lower Cl, Upper Cl]
    All Respiratory Outcomes: 1.003 [0.982, 1.025]
    URI: 1.013 [0.987, 1.039]
    Asthma: 0.998 [0.987 1.039]
    Pneumonia: 0.975 [0.940, 1.011]
    COPD: 0.948 [0.897, 1.003]
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    December 2009
    E-259
    

    -------
            Reference
           Design & Methods
         Concentrations!
                Effect Estimates (95% Cl)
    Reference: Peng et al. (2008,
    1568501
    
    Period of Study: Jan
    1999-Dec2005
    
    Location: 108 U.S. counties
    in the following states:
    Alabama, Arizona, California,
    Colorado, Connecticut,
    District of Columbia, Florida,
    Georgia, Idaho, Illinois,
    Indiana, Kentucky, Louisiana,
    Maine,  Maryland,
    Massachusetts, Michigan,
    Minnesota, Missouri,  Nevada,
    New Hampshire, New Jersey,
    New Mexico, New York, North
    Carolina, Ohio, Oklahoma,
    Oregon, Pennsylvania, Rhode
    Island,  South Carolina,
    Tennessee,  Texas, Utah,
    Virginia, Washington, West
    Virginia, Wisconsin
    Outcome (ICD-9): Emergency
    hospitalizations for respiratory
    disease, including COPD (490-492)
    and respiratory tract infections
    (464-466, 480 - 487)
    
    Age Groups: 65 + yr, 65-74, ,75 +
    
    Study Design: Time series
    
    N: Approximately 12 million Medicare
    enroilees (1.4 million RD admissions)
    
    Statistical Analyses: Two-stage
    Bayesian hierarchical models: Over
    dispersed Poisson models for county-
    specific data. Bayesian hierarchical
    models to obtain national avg
    estimate
    
    Covariates: Day of the week, age-
    specific intercept, temperature, dew
    point temperature, calendar time,
    indicator for age of 75 yr or older.
    Some models were adjusted for
    PM25.
    
    Dose-response Investigated: No
    
    Statistical Package: R version 2.6.2
    
    Lags Considered: 0-2 days
    Pollutant: PM10.2.5
    
    Averaging Time: 24 h
    
    Mean (IQR): All counties
    assessed: 9.8 (6.9-15.0)
    
    Counties in Eastern U.S.: 9.1
    (6.6-13.1)
    
    Counties in Western U.S.: 15.4
    (10.3-21.8)
    
    Monitoring Stations: At least 1
    pair of co-located monitors
    (physically located in the same
    place) for PMi0 and PM25 per
    county
    
    Copollutant (correlation):
    PM25:r = 0.12
    
    PM10:r = 0.75
    
    Other variables:  Median within-
    county correlations between
    monitors: r = 0.60
    PM Increment: 10|jg/m
    
    Percentage change [95% Cl]: Respiratory disease (RD):
    Lag 0 (unadjusted for PM25): 0.33 [-0.21, 0.86]
    
    Lag 0 (adjusted for PM25): 0.26 [-0.32, 0.84]
    
    Most values NR (see note)
    
    Notes: Fig 3: Percentage change in emergency hospital
    admissions for RD per 10 pg/m increase in PM (single
    pollutant model and model adjusted for PM25 concentration)
    
    Fig 4: Percentage change in emergency  hospital
    admissions rate for CVD and RD per a 10 pg/m3 increase in
    PM10.25 (0-2 day lags, Eastern vs.. Western USA)
    Reference: Slaughter et al.
    (2005, 0738541
    
    Period of Study:
    Jan 1995-Jun 2001
    
    Location: Spokane, WA
    Hospital Admissions and ED visits
    
    Outcome: All respiratory (460-519)
    Asthma (493)
    COPD (491,492, 494,496)
    Pneumonia (480-487)
    Acute URI not including colds and
    sinusitis (464, 466, 490)
    
    Age Groups: All, 15+ yr for COPD
    
    Study Design: Time series
    
    N: 2373 visit records
    
    Statistical Analyses: Poisson
    regression, GLM with natural splines.
    For comparison also  used GAM with
    smoothing splines and default
    convergence criteria.
    
    Covariates: Season, temperature,
    relative humidity, day of week
    
    Season: All
    
    Dose-response Investigated?: No
    
    Statistical Package: SAS, SPLUS
    
    Lags Considered: 1 -3 days
    Pollutant: PMi0.25 (fjg/m )
    
    Averaging Time: 24 h avg
    
    Range (90% of
    Concentrations): Reported for
    PM25and PM10only
    
    Monitoring Stations: 1
    
    Copollutant (correlation):
    PM,0-2.5
    
    PM1r = 0.19
    
    PM25r = 0.31
    
    PM10r = 0.94
    
    CO r = 0.32
    
    Temperature r = 0.11
    PM Increment: 25 pg/m
    
    RR Estimate [Lower Cl, Upper Cl] I
    
    ER visits:
    
    PM,0-2.5
    
    All Respiratory
    
    Lag 1:1.01 [0.98,1.04]
    
    Lag 2:1.01 [0.98,1.04]
    
    Lag 3:1.02 [0.99,1.05]
    
    Acute Asthma
    
    Lag 1:1.03 [0.98,1.08]
    
    Lag 2:1.01 [0.96,1.07]
    
    Lag 3: 0.99 [0.94, 1.05]
    
    COPD (adult)
    
    Lag 1:1.01 [0.93,1.09]
    
    Lag 2: 0.98 [0.90, 1.06]
    
    Lag 3:1.02 [0.95,1.10]
    December 2009
                                             E-260
    

    -------
    Reference
    Reference: Tecer et al.
    (2008, 1800301
    Period of Study:
    Dec 2004-Oct 2005
    Location: Zonguldak, Turkey
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Yang etal.,
    (2004, 087488)
    
    Period of Study:
    Jun1995-MaM999
    Location: Vancouver area,
    British Columbia
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: ED visits for respiratory
    problems (ICD-9 470-478, 493)
    Study Design: Bidirectional Case-
    crossover
    Covariates: Daily meteorological
    parameters
    Statistical Analysis: Conditional
    logistic regression
    Statistical Package: Stata
    Age Groups: 0-14 yr
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Hospital Admissions
    Outcome (ICD-9): Respiratory
    diseases (460-51 9), pneumonia only
    (480-486), asthma only (493)
    Age Groups: 0-3 yr
    Study Design: Case control,
    bidirectional case-crossover (BCC),
    and time series (TS)
    N: 1610 cases
    
    Statistical Analyses: Chi-square
    test, Logistic regression, GAM (time-
    series), GLM with parametric natural
    cubic splines
    Covariates: Gender, socioeconomic
    status, weekday, season, study yr,
    influenza epidemic month
    Season: Spring, summer, fall, winter
    Dose-response Investigated? No
    Statistical Package: SAS (Case
    control and BCC), S-Plus (TS)
    Lags Considered: 0-7 days
    Concentrations!
    Pollutant: PM10.2.5
    Averaging Time: NR
    Mean, Unit: 24.3 pg/m3
    Range (Min, Max): 4, 195.8
    Copollutant (correlation):
    PM2.5/PM10.2,
    Mean: 1.49
    Range: 0.21, 7.53
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM10.2.5 (|jg/m3)
    Averaging Time: 24 h
    Mean (min-max):
    5.6 (0-24.6)
    SD = 3.6
    Monitoring Stations: NR (data
    obtained from Greater
    Vancouver Regional District Air
    Quality Dept)
    Copollutant (correlation):
    PM25: r = 0.39
    PM10:r = 0.83
    CO1 r = 0 33
    
    03:r = -0.16
    N02:r = 0.37
    S02:r = 0.54
    
    
    
    Effect Estimates (95%
    Increment: 10 pg/m3
    Odds Ratio (96% Cl)
    Asthma
    Lag 0:1. 18 (1.01-1.39)
    Lag 1:0.92 0.78-1.08
    Lag 2: 0.98 0.84-1.15
    Lag 3: 1.11 (0.97-1. 27)
    Lag 4: 1.17 (1.05-1.31)
    Allergic Rhinitis with Asthma
    Lag 0:0.96 (0.88-1. 04)
    Lag 1:1. 08 0.99-1.18
    Lag 2: 0.93 0.86-1.02
    Lag 3: 0.94 (0.86-1. 03)
    Lag 4: 1.10 (1.03-1. 18)
    Allergic Rhinitis
    Lag 0:1. 06 (0.95-1. 19)
    Lag 1:1. 17 1.04-1.31
    Lag 2: 0.92 0.84-1.02
    Lag 3: 0.99 (0.91-1.08)
    Lag 4: 1.15 (1.06-1. 25)
    Upper Respiratory Disease
    Lag 0:0.80 (0.54-1. 19)
    Lag 1:1. 22 0.92-1.61
    Lag 2: 0.97 0.70-1.33
    Lag 3: 0.94 (0.66-1. 33)
    Lag 4: 1.08 (0.88-1. 32)
    Lower Respiratory Disease
    Lag 0:0.90 (0.71-1. 16)
    Lag 1:1. 20 0.97-1.50
    Lag 2: 1.00 0.84-1.19
    Lag 3: 1.26 (1.08-1. 47)
    Lag 4: 1.02 (0.93-1. 13)
    PM Increment: 4.2 pg/m3 (IQR)
    OR Estimate [Cl]:
    3-day lag
    1.12 [0.98,1.28]
    Adj for gaseous pollutants: 1.22 [1.02,1.45
    Cl)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    ]
    Notes: Author states that ORs for PM10.2.5 increased with lag
    time up to 3 days for both single and multiple-pollutant
    models. More adjusted ORs and RRs are provided in Fig 1.
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    All units expressed in pg/m  unless otherwise specified.
    December 2009
    E-261
    

    -------
    Table E-14.     Short-term exposure-respiratory-ED/HA-PWhs (including PM components/sources).
               Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Andersen et al. (2008,
    1896511
    Period of Study: May 2001-Dec 2004
    
    Location: Copenhagen, Denmark
    Outcome (ICD-10): RD, including
    chronic bronchitis (J41-42),
    emphysema (J43), other chronic
    obstructive pulmonary disease (J44),
    asthma (J45), and status asthmaticus
    (J46). Pediatric hospital admissions for
    asthma (J45) and status asthmaticus
    (J46).
    
    Age Groups: > 5-18 yr (asthma)
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Poisson GAM
    
    Covariates: Temperature, dew-point
    temperature, long-term trend,
    seasonality, influenza, day of the week,
    public holidays, school holidays (only
    for 5-18 yr olds),  pollen (only for
    pediatric asthma  outcome)
    
    Season: NR
    
    Dose-response  Investigated: No
    
    Statistical Package: R statistical
    software (gam  procedure, mgcv
    package)
    
    Lags Considered: Lag 0-5 days, 4-day
    pollutant avg (lag 0-3) for CVD, 5-day
    avg (lag 0-4) for RD, and a 6-day avg
    (lag 0-5) for asthma.
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean |jg/m3(SD): 10(5)
    
    Median: 9
    
    IQR:7-12
    
    99th percentile: 28
    
    Monitoring Stations: 1
    Copollutant (correlation):
    NCtot:r = 0.40
    NC100:r = 0.29
    NCa12:r = 0.07
    Nca23:r = -0.25
    NCa57:r = 0.51
    NCa212:r = 0.82
    PM10:r = 0.80
    CO: r = 0.46
    N02:r =  0.42
    :r = 0.40
    NCycurbside: r = 0.28
    03:r = -0.20
    Other variables:
    Temperature: r = -0.01
    Relative  humidity:  r = 0.21
    PM Increment: 5 pg/m  (IQR)
    
    Relative risk (RR) Estimate [Cl]: RD
    hospital admissions (5-day avg, lag
    0-4), age 65+:
    
    One-pollutant model: 1.00 [0.95-1.00]
    
    Adj for NCtot: 1.00 [0.95-1.06]
    
    Asthma hospital admissions (6-day avg
    lag 0-5), age 5-18:
    
    One-pollutant model: 1.15 [1.00-1.32]
    
    Adj for NCtot: 1.13 [0.98-1.32]
    
    Estimates for individual day lags
    reported only in Fig form (see notes):
    
    Notes: RD: No statistically or marginally
    significant associations. Positive
    associatons at Lag 4-5.Asthma: Wide
    confidence intervals make interpretation
    dificult.  Positive associations at Lag 1,
    2,3.
    Reference: Babin et al. (2007, 0932501
    
    Period of Study: Oct 2001-Sep 2004
    
    Location: Washington, DC
    ED Visit/Admissions
    
    Outcome: Asthma-493
    
    Age Groups: 1-17 yr,1-4, 5-12,13-17
    
    Study Design: Time-series
    
    N:NR
    
    Statistical Analyses: Poisson
    regression, spline w/12 knots to adjust
    for long term trend
    
    Covariates: Temperature, mold, pollen,
    seasonal trends,
    
    Season: All
    
    Dose-response lnvestigated?No
    
    Statistical Package: STATA
    
    Lags Considered: 0-4
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean: "low, never reached code red"
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: 3
    
    Copollutant (correlation): NR
    PM Increment: 1 pg/m
    
    %Change ED Visits
    
    Ages 5-12:
    
    -0.2 (-0.6,0.2), lag 0
    
    % Change ED Admissions:
    
    Ages 5-12:
    
    -0.4 (-1.6,0.8), lag 0
    
    Ages 1-17:
    
    0.2 (-0.6,1.1), lag 0
    
    AR Estimate [Lower Cl, Upper Cl] lag:
    NR
    
    Notes: No significant interactions
    between PM and 03 or other covariates
    were observed.
    December 2009
                                   E-262
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Barnett et al. (2005,
    0873941
    Period of Study: 1998-2001
    
    Location: 5 Australian cities (Brisbane,
    Canberra, Melbourne, Perth, and
    Sydney) and 2 New Zealand cities
    (Auckland, Christchurch)
    Outcome (ICD: NR): All respiratory
    admissions (including asthma,
    pneumonia, and acute bronchitis)
    
    Age Groups: Children aged <1 yr, 1-
    4yr, and 5-14 yr
    
    Study Design: Matched case-
    crossover
    
    N: ~2.4 million children <15 yr old
    
    Statistical Analyses: Random effects
    meta-analysis
    
    Covariates: Temperature, current
    minus previous day's temperature,
    relative humidity, pressure, extremes
    of hot and cold, day of the week,
    public holiday, and day after public
    holiday
    
    Season: Warm (Nov-Apr) and Cool
    (May-Oct)
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: NR
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (min-max):
    
    Auckland (A): 11.0(2.1-37.6)
    
    Brisbane (B): 9.7 (3.2-122.8)
    
    Canberra (Ca): NR
    
    Christchurch (Ch): NR
    
    Melbourne (M): 8.9 (2.8-43.3)
    
    Perth (P): 8.1 (1.7-29.3)
    
    Sydney (S): 9.4 (2.4-82.1)
    
    Monitoring Stations: 1-3 per city
    
    Copollutant: NR
    PM Increment: 3.8 pg/m (IQR)
    
    Percent Increase Estimate [Cl]:
    Pneumonia S Acute Bronchitis:
    Single Pollutant Model
    <1yr(B,M,P,S): 1.7 [0.0,3.4
    1-4 yr(B,M,P,S): 2.4 [0.1,4.7
    Matched Multipollutant Model
    1-4 yr with 1-hS02(B,S): 1.9 [-1.7,5.6]
    1-4 yr with temp (B,M,P,S): 2.3 [-0.4,5.1]
    Respiratory Admissions:
    Single Pollutant Model
    <1yr(B,M,P,S): 2.4 [1.0,3.8]
    1-4 yr(B,M,P,S): 1.7 [0.7,2.7]
    Matched Pollutant Model
    <1yr with 1-hS02(B,S): 3.1 [0.5,5.7]
    <1 yr with temp (B,M,P,S): 1.8 [0.2,3.4]
    1-4 yrwith PM,0 (B,M,P,S): 2.9 [0.2,5.6]
    1-4 yr with 1-hS02(B,S): 1.3 [-1.8,4.4]
    1-4 yr with 1-h N02 (B,M,P,S):
    -1.5 [-3.2,0.2]
    1-4 yrwith temp (B,M,P,S,):
    1.5 [-0.2,3.1]
    Reference: Bell et al. (2008, 0912681
    
    Period of Study: 1995-2002
    
    Location: Taipei, Taiwan
    Outcome (ICD-9): Hospital admissions
    for asthma (493), and pneumonia (486).
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 19,966 hospital admissions for
    pneumonia, and 10,231 for asthma
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Day of the week, time,
    apparent temperature, long-term trends,
    seasonality
    
    Season: All
    
    Dose-response Investigated: No
    
    Statistical Package: NR
    
    Lags Considered: lags 0-3 days, mean
    of lags 0-3
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (range
    
    IQR): 31.6 (0.50-355.0
    
    20.2)
    
    Monitoring Stations: 2
    
    Copollutant (correlation): NR
    PM Increment: 20 pg/m  (near IQR)
    
    Percentage increase estimate [95% Cl]:
    Asthma: L0:0.46 (-2.41, 3.42)
    
    L1:-1.36 (-4.33, 1.71)
    
    L2:-0.83 (-3.67, 2.10)
    
    L3:-0.78 (-3.63, 2.16)
    
    LOS:-1.75 (-6.21, 2.92)
    
    Pneumonia: LO: 0.06 (-2.74, 2.94)
    
    L1:0.34 (-2.446, 3.20)
    
    L2: -0.59 (-3.38, 2.29)
    
    L3:-0.44 (-3.22, 2.41)
    
    LOS: -0.61  (-4.87, 3.85)
    Reference: Bell et al. (2008, 0912681
    
    Period of Study: 1999-2005
    
    Location: 202 U.S. counties
    Outcome (ICD-9): COPD (490-492),
    respiratory tract infections (464-466,
    480-487)
    
    Age Groups: 65+
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Two-stage
    Bayesian hierarchical model to find
    national avg
    
    First stage: Poisson regression (county-
    specific)
    
    Covariates:  Day  of the week,
    temperature, dew point temperature,
    temporal trends, indicator for persons
    75+ yr,  population size
    
    Season: All,  Jun-Aug (Summer),
    Sep-Nov (Fall), Dec-Feb (Winter),
    Mar-May (Spring)
    
    Dose-response Investigated: No
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (ug/m3):
    
    Descriptive information presented in Fig
    S2 (boxplots):
    
    IQR: 8.7 pg/m3
    
    Monitoring Stations: NR
    
    Copollutant (correlation): NR
    PM Increment: 10 pg/m
    Percent increase [95% PI]:
    Respiratory admissions:
    Lag 0 (all seasons): 0.22 [-0.12-0.56]
    Lag 0 (winter, national): 1.05 [0.29-1.82]
    Lag 0 (winter, northeast):
    1.76 [0.60-2.93]
    Lag 0 (winter, southeast):
    0.59 [-1.35-2.58]
    Lag 0 (winter, northwest):
    -0.07 [-6.74-7.08]
    Lag 0 (winter, southwest):
    0.03[-1.25-1.34]
    Lag 0 (spring, national):
    0.31 [-0.47-1.11]
    Lag 0 (spring, northeast):
    0.34 [-0.66-1.34]
    Lag 0 (spring, southeast):
    -0.06 [-1.77-1.68]
    Lag 0 (spring, northwest):
    -8.52 [-25.62-12.51]
    Lag 0 (spring, southwest):
    1.87 [-2.00-5.90]
    Lag 0 (summer, national):
    -0.62 [-1.33-0.09]    	
    December 2009
                                     E-263
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                         Statistical Package: NR
    
                                         Lags Considered: 0-2 day lags
                                                                              Lag 0 (summer, northeast):
                                                                              -0.8 [-1.65-0.07]
                                                                              Lag 0 (summer, southeast):
                                                                              -0.15 [-1.88-1.61]
                                                                              Lag 0 (summer, northwest):
                                                                              0.25 [-21.46-27.96]
                                                                              Lag 0 (summer, southwest):
                                                                              0.64 [-5.38-7.04]
                                                                              Lag 0 (fall, national):
                                                                              0.02 [-0.63-0.67]
                                                                              Lag 0 (fall, northeast):
                                                                              -0.01 [-0.87-0.85]
                                                                              Lag 0 (fall, southeast):
                                                                              -0.58 [-2.06-0.91]
                                                                              Lag 0 (fall, northwest):
                                                                              -1.38[-11.84-10.32]
                                                                              Lag 0 (fall, southwest):
                                                                              1.77 [-0.73-4.33]
                                                                              Lag 1 (all seasons): 0.05 [-0.29-0.39]
                                                                                                                   Lag1
                                                                                                                   Lag1
                                                                                     winter): 0.50 [-0.27-1.27]
                                                                                     spring):-0.24 [-1.01-0.53]
                                                                                                                   Lag 1 (summer): 0.28 [-0.39-0.95]
                                                                                                                   Lag1
                                                                                                                   Lag 2
                                                                                     fall): 0.15 [-0.49-0.79]
                                                                                     all seasons): 0.41 [0.09-0.74]
                                                                                                                   Lag 2 (winter, national): 0.72 [0.01-1.43]
                                                                                                                   Lag 2 (winter, northeast):
                                                                                                                   0.79 [-0.21-1.80]
                                                                                                                   Lag 2 (winter, southeast):
                                                                                                                   0.4 [-1.45, 2.27]
                                                                                                                   Lag 2 (winter, northwest):
                                                                                                                   -0.06 [-6.52-6.85]
                                                                                                                   Lag 2 (winter, southwest):
                                                                                                                   1.2 [-0.10-2.52]
                                                                                                                   Lag 2 (spring, national):
                                                                                                                   0.35 [-0.29-0.99]
                                                                                                                   Lag 2 (spring, northeast):
                                                                                                                    0.04 [-0.88-0.97]
                                                                                                                   Lag 2 (spring, southeast):
                                                                                                                   0.75 [-0.82-2.34]
                                                                                                                   Lag 2 (spring, northwest):
                                                                                                                   2.29 [-14.26-22.03]
                                                                                                                   Lag 2 (spring, southwest):
                                                                                                                   1.05 [-2.18-4.39]
                                                                                                                   Lag 2 (summer, national): 0.57 [-
                                                                                                                   0.07-1.23]
                                                                                                                   Lag 2 (summer, northeast):
                                                                                                                   0.77[-0.01-1.56]
                                                                                                                   |Lag 2  (summer,  southeast):
                                                                                                                   -0.52 [-2.07-1.06]
                                                                                                                   Lag 2 (summer, northwest):
                                                                                                                   0.74 [-18.73-24.86]
                                                                                                                   Lag 2 (summer, southwest):
                                                                                                                   2.41  [-2.61-7.69]
                                                                                                                   Lag 2 (fall, national):
                                                                                                                   0.39 [-0.22-1.01]
                                                                                                                   Lag 2 (fall, northeast):
                                                                                                                   0.12 [-0.82-1.07]
                                                                                                                   Lag 2 (fall, southeast):
                                                                                                                   0.14[-1.29-1.59]
                                                                                                                   Lag 2 (fall, northwest):
                                                                                                                   -0.74 [-10.08-9.58]
                                                                                                                   Lag 2 (fall, southwest):
                                                                                                                   0.97[-1.36-3.36]      	
    Reference: Bell et al. (2009,1910071
    
    Period of Study: 1999-2005
    
    Location: 168 U.S. Counties
    Outcome: Respiratory hospital
    admissions
    
    Study Design: Retrospective Cohort
    
    Covariates: Socio-economic
    conditions, long term temperature
    
    Statistical Analysis: Bayesian
    hierarchical model
    
    Age Groups: >65
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD) Unit: NR
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 20% of the population
    acquiring air conditioning
    
    Percent Change (96% Cl) in
    community-specific PM health effect
    estimates for respiratory hospital
    admissions
    Any AC, including window units
    Yearly health effect: 44.5 (-87.5-176)
    Summer health effect: -74.8 (-417-267)
    Winter health effect: -32.5 (-245-180)
    Central AC
    Yearly health effect: 27.6 (-46.7-102)
    Summer health effect: -38.6 (-160-82.6)
    Winter health effect: 43.8 (-125-213)
    December 2009
                                     E-264
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Bell et al. (2009,1910071
    
    Period of Study: 1999-2005
    
    Location: 168 U.S. Counties
    Outcome: Respiratory HA
    
    Age Groups: 65+
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Bayesian
    Hierarchical Regression
    
    Covariates: Time trend, day of week,
    seasonality, dew point, temperature
    
    Statistical Package: NR
    
    Lags Considered: 0-2
    Pollutant: PM25
    
    Averaging Time: Daily
    Mean:
    EC: 0.715
    Ni: 0.002
    V: 0.003
    Min:
    EC: 0.309
    Ni: 0.003
    V: 0.001
    Max:
    EC: 1.73
    Ni: 0.021
    V: 0.010
    Interquartile Range:
    EC: 0.245
    Ni: 0.001
    V: 0.001
    Interquartile Range of Percents:
    EC: 1.7
    Ni:0.01
    V: 0.01
    Monitoring Stations: NR
    
    Copollutant: Al, NH4+, As, Ca, Cl, Cu,
    EC, CMC, Fe, Pb, Mg. Ni, N0r, K, Si,
    Na+, S04=,  Ti, V, Zn
    
    Co-pollutant Correlation:
    Ni, V: 0.48
    V, EC: 0.33
    Ni, EC: 0.30
    
    Note: Pollutant concentrations available
    for all fractions of PM2 5
    PM Increment: Interquartile Range in
    the fraction of PM2 5
    
    Percent Increase (Lower Cl, Upper
    Cl):
    EC: 511  (80.7, 941), lag 0
    EC+Ni: 399 (-45.1, 843), lag 0
    EC + V: 386 (-74.8, 846), lag 0
    EC + Ni, V: 362 (-98.0, 823), lag 0
    Ni: 223 (36.9, 410), lagO
    Ni +EC: 176 (-18.7, 370), lag 0
    Ni + V:151 (-78.4, 381), lag 0
    Ni + EC, V: 136 (-94.9, 368), lag 0
    V: 392 (46.3, 738), lag 0
    V + EC: 279 (-93.2, 651), lagO
    V+Ni: 230(-193.7, 653), lagO
    V+EC, Ni: 140 (-300, 579), lagO
    EC:-1.5 (80.7, 941), lag 1
    EC: 17.5 (-22.3, 57.3), lag 2
    Ni:-7.2 (-66.6. 52.1), lag 1
    Ni: -4.9 (-22.3, 12.5), lag 2
    V:-19.6 (-127, 88.3), lag 1
    V: 10.5 (-21.5, 42.4),  lag 2
    HS education: -77.8 (-390,  234), lag  0
    median income: 45.9 (-411, 503), lagO
    Percent black: -53.1 (-557,  451), lag  0
    Percent living in urban area: -41.9 (-
    774.7, 691), lag 0
    Population:-22.9 (-121, 75.3), lag 0
    Notes: Interquartile ranges in percent
    HS education, median income, percent
    black, percent living in urban area, and
    population are 5.2 %, $9,223,17.3%,
    11.0%, and 549,283 respectively.
    Reference: Chardon et al. (2007,
    0913081
    
    Period of Study: 2000-2003
    
    Location: Greater Paris Area, France
    Doctors house calls
    
    Outcome (ICPC2): Asthma (R96),
    Upper respiratory disease (URD R07,
    R21.R29, R75, R76, R02), Lower
    respiratory disease (LRD, R05, R78)
    
    Age Groups: All
    
    Study Design: Time series
    
    N: 8027 for asthma
    52928 for LRD
    74845 for URD
    
    Statistical Analyses: Quasi-Poisson,
    GAM, parametric penalized spline
    smoothers.
    
    Covariates: Lagged and current
    temperature,  humidity, long term trends,
    seasonality, pollen counts,  influenza
    epidemic, days of the week, holidays,
    bank holidays
    
    Season: All
    
    Dose-response Investigated? No
    
    Statistical Package: R
    
    Lags Considered: 0-3 days
    Pollutant: PM25
    
    Averaging Time: Mean of the daily
    means
    
    Mean (SD): 14.7(7.34) pg/m3
    
    Percentiles: 25th: 9.5
    
    SOth(Median): 12.9
    
    75th: 18.2
    
    Range (Min, Max): (3, 69.6)
    
    Monitoring Stations: 1-4
    
    Copollutant:
    
    PM,0:r = 0.95
    
    N02:r = 0.68
    PM Increment: 10 pg/m3
    
    % Change, lag 0-3-day avg
    
    URD
    
    6.0(3.1,9.1)
    
    LRD
    
    5.8 (2.8, 8.9)
    
    Asthma
    
    4.4 (-1.3, 10.4)
    December 2009
                                    E-265
    

    -------
                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chen et al. (2005, 0875551
    
    Period of Study: Jun 1995-Mar 1999
    
    Location: Vancouver area, BC
    Hospital Admissions
    
    Outcome (ICD-9): Acute respiratory
    infections (460-466), upper respiratory
    tract infections (470-478), pneumonia
    and influenza (480-487), COPD and
    allied conditions (490-496), other
    respiratory diseases (500-519)
    
    Age Groups: >65 yr
    
    Study Design: Time series
    
    N: 12,869
    
    Statistical Analyses: GLM
    
    Covariates: Temp and relative humidity
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: S-Plus
    
    Lags Considered:  1-, 2-, 3-, 4-, 5-, 6-,
    and 7-day avg
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (min-max):
    
    7.7 (2.0-32.0)
    
    SD = 3.7
    
    Monitoring Stations: 13
    Copollutant (correlation):
    PM,o:r = 0.83
    PMi0.25:r = 0.38
    COM: r = 0.39
    CO: r = 0.23
    03:r = -0.01
    N02:r = 0.36
    S02:r = 0.42
    Other variables:
    
    Mean temp: r = 0.41
    
    Pel humidity: r = -0.23
    PM Increment: 4.0 pg/rri (IQR)
    
    RR Estimate [Cl]:
    
    Adj for weather conditions
    
    Overall admission
    
    1-day avg: 1.02 [0.99,1.05]
    
    2-day avg: 1.02 [0.99,1.06]
    
    3-day avg: 1.02 [0.98,1.05]
    
    Adj for weather conditions and
    co pollutants
    
    Overall admission
    
    1-day avg: 1.01 [0.98,1.06]
    
    2-day avg: 1.01 [0.98,1.05]
    
    3-day avg: 1.00 [0.96,1.04]
    
    Notes: PR's were also provided for lags
    4-7 in Table 3, yielding similar results
    Reference: Chimonas and Gessner
    (2007, 0932611
    
    Period of Study: Jan 1999-Jun 2003
    
    Location: Anchorage, Alaska
    Outcome (ICD-9): Asthma (493.0-
    493.9)
    Lower respiratory illness-LRI (466.1,
    466.0, 480-487, 490, 510-511)
    Inhaled quick-relief medication
    Steroid medication
    
    Age Groups: <20 yr old
    
    Study Design: Time series
    
    N: 42,667 admissions
    
    Statistical Analyses: GEE for
    multivaliable modeling
    
    Covariates:  Season, serial correlation,
    yr, weekend, temperature, precipitation,
    and wind speed
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: SPSS (dataset),
    SAS (analysis)
    
    Lags Considered: 1 day and 1 wk
    Pollutant: PM25
    
    Averaging Time: 24 h and 1 wk
    
    Mean (min-max):
    
    Daily: 6.1 (0.5-69.8)
    
    Weekly: 5.8 (1.8-45.0)
    
    Monitoring Stations: NR
    
    Copollutant: N/A
    PM Increment: 5 pg/m
    
    RR Estimate [Cl]:
    
    Same Day
    Outpatient Asthma: 0.992 [0.964,1.024]
    Outpatient LRI: 0.952 [0.907,1.001]
    Inpatient Asthma: 0.936 [0.798,1.098]
    Inpatient LRI: 0.919 [0.823,1.027]
    Inhaled Steroid Prescriptions:
    0.988 [0.902,1.083]
    Quick-relief Medication:
    0.962 [0.901,1.028]
    Weekly (median increase)
    Outpatient Asthma: 0.983 [0.935,1.038]
    Outpatient LRI: 0.969 [0.874,1.075]
    Inpatient Asthma: 0.754 [0.513.1.109]
    Inpatient LRI: 0.943 [0.715,1.245]
    Inhaled Steroid Prescriptions:
    1.018 [0.883,1.175]
    Quick-relief Medication:
    0.978 [0.882,1.087]
    Reference: Delfmo et al. (2009,
    1919941
    Period of Study: Oct 2003-Nov 2003
    
    Location: Southern California
    Outcome: Respiratory hospital
    admissions
    
    Study Design: Time series
    
    Statistical Analysis: Poisson
    regression with GEE
    
    Age Groups: All
    Pollutant: PM25
    
    Averaging Time: Hourly
    
    Mean (SD) Unit by county:
    Los Angeles
    Before Fires: 27.2 (12.4) pg/m3
    During Fires: 54.1 (21.0)|jg/m3
    After Fires: 15.9(5.5) pg/m
    Orange
    Before Fires: 23.2 (9.6) pg/m3
    During Fires: 64.3 (26.5) pg/m3
    After Fires: 15.5 (10.2) pg/m3
    Riverside
    Before Fires: 32.7 (14.7) pg/m3
    During Fires: 42.1 (25.5) pg/m
    After Fires: 16.9 (10.2) pg/m3
    San Bernadino
    Before Fires: 35.7 (16.6) pg/m3
    During Fires: 45.3 (28.7) pg/m3
    After Fires: 18.5(8.3) pg/m
    San Diego
    Before Fires: 18.5 (6.7) pg/m3
    During Fires: 76.1 (66.6) pg/m3
    After Fires: 14.2 (7.2) pg/nf
    Ventura
    Increment: 10|jg/m
    
    Relative Rate (Min Cl, Max Cl)
    
    All Respiratory, All Ages: All Periods:
    1.009(0.999-1.018)
    Pre-Wildfire: 1.022 (1.004-1.040)
    Wildfire: 1.028 (1.014-1.041), p = 0.639
    Post-Wildfire: 0.999 (0.968-1.031),
    p = 0.198
    
    All Respiratory, Ages 0-4: All Periods:
    0.994(0.967-1.021)
    Pre-Wildfire: 0.982 (0.921-1.046)
    Wildfire: 1.045 (1.010-1.082), p = 0.103
    Post-Wildfire: 0.894 (0.807-0.991),
    p = 0.126
    
    All Respiratory, Ages 5-19: All Periods:
    1.014(0.983-1.046)
    Pre-Wildfire: 1.026 (0.946-1.113)
    Wldfire: 1.027 (0.984-1.076), p = 0.990
    Post-Wildfire: 0.958 (0.852-1.077),
    p = 0.354
    
    All Respiratory, Ages 20-64: All Periods:
    December 2009
                                     E-266
    

    -------
                Reference
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                             Before Fires: 18.4 (8.3) pg/nf
                                                                             During Fires: 50.1 (50.5) pg/m3
                                                                             After Fires: 12.9 (4.3) pg/rri
                                                                             Copollutant (correlation): NR
                                                                      1.015(1.002-1.029)
                                                                      Pre-Wildfire: 1.036 (1.007-1.066)
                                                                      Wildfire: 1.024(1.005-1.044), p = 0.534
                                                                      Post-Wildfire: 1.007 (0.960-1.056),
                                                                      p = 0.315
    
                                                                      All Respiratory, Ages 65-99: All Periods:
                                                                      1.009(0.996-1.022)
                                                                      Pre-Wildfire: 1.022 (0.994-1.050)
                                                                      Wildfire: 1.030(1.011-1.049), p = 0.649
                                                                      Post-Wildfire: 1.024 (0.967-1.074),
                                                                      p = 0.932
    
                                                                      Asthma, All Ages, Male and Female: All
                                                                      Periods: 1.022 (1.001-1.042)
                                                                      Pre-Wildfire: 0.998 (0.949-1.050)
                                                                      Wldfire: 1.048 (1.021-1.076), p = 0.097
                                                                      Post-Wildfire: 0.986 (0.910-1.068),
                                                                      p = 0.792
    
                                                                      Asthma, All Ages, Male: All Periods:
                                                                      1.010(0.980-1.040)
                                                                      Pre-Wldfire: 1.021 (0.944-1.106)
                                                                      Wldfire: 1.031 (0.990-1.073), p = 0.848
                                                                      Post-Wildfire: 1.063 (0.948-1.192),
                                                                      p = 0.553
    
                                                                      Asthma, All Ages, Female: All Periods:
                                                                      1.029(1.001-1.058)
                                                                      Pre-Wldfire: 0.979 (0.913-1.050)
                                                                      Wldfire: 1.059(1.022-1.097), p = 0.056
                                                                      Post-Wldfire: 0.928 (0.829-1.037),
                                                                      p = 0.412
    
                                                                      Asthma, Ages 0-4, Males and Females:
                                                                      All Periods: 0.996 (0.947-1.048)
                                                                      Pre-Wldfire: 0.924 (0.824-1.035)
                                                                      Wldfire: 1.083 (1.021-1.149), p = 0.017
                                                                      Post-Wldfire: 0.924 (0.767-1.113),
                                                                      p = 0.999
    
                                                                      Asthma, Ages 0-4, Males: All  Periods:
                                                                      1.018(0.963-1.076)
                                                                      Pre-Wldfire: 0.942 (0.815-1.089)
                                                                      Wldfire: 1.086 (1.016-1.162), p = 0.101
                                                                      Post-Wldfire: 1.057 (0.839-1.332),
                                                                      p = 0.380
    
                                                                      Asthma, Ages 0-4, Females: All
                                                                      Periods: 0.937 (0.845-1.040)
                                                                      Pre-Wldfire: 0.880 (0.706-1.099)
                                                                      Wldfire: 1.073 (0.965-1.194), p = 0.116
                                                                      Post-Wldfire: 0.699 (0.515-0.949),
                                                                      p = 0.214
    
                                                                      Asthma, Ages 5-19, Males and
                                                                      Females: All Periods:
                                                                      1.006(0.966-1.048)
                                                                      Pre-Wldfire: 1.045 (0.936-1.167)
                                                                      Wldfire: 0.999 (0.935-1.068), p = 0.492
                                                                      Post-Wldfire: 0.918 (0.788-1.069),
                                                                      p = 0.198
    
                                                                      Asthma, Ages 5-19, Males: All Periods:
                                                                      0.991 (0.935-1.051)
                                                                      Pre-Wldfire: 1.034 (0.892-1.198)
                                                                      Wldfire: 0.969 (0.883-1.064), p = 0.462
                                                                      Post-Wldfire: 0.979 (0.806-1.189),
                                                                      p = 0.671
                                                                      Asthma, Ages 5-19, Females: All
                                                                      Periods: 1.026 (0.964-1.092)
                                                                      Pre-Wldfire: 1.065 (0.901-1.260)
                                                                      Wldfire: 1.033 (0.943-1.132), p = 0.768
                                                                      Post-Wldfire: 0.831 (0.640-1.079),
                                                                      p = 0.136
    
                                                                      Asthma, Ages 20-64, Males and
                                                                      Females: All Periods: 1.043(1.012-
    December 2009
                             E-267
    

    -------
                Reference                     Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                   1076)
                                                                                                                   Pre-Wildfire: 1.037 (0.957-1.123)
                                                                                                                   Wildfire: 1.041 (0.995-1.090), p = 0.931
                                                                                                                   Post-Wildfire: 1.000 (0.882-1.132),
                                                                                                                   p = 0.624
    
                                                                                                                   Asthma, Ages 20-64,  Males: All Periods:
                                                                                                                   1.013(0.954-1.077)
                                                                                                                   Pre-Wildfire: 1.159 (0.996-1.349)
                                                                                                                   Wildfire: 0.939 (0.837-1.053), p = 0.026
                                                                                                                   Post-Wildfire: 1.275 (1.020-1.595),
                                                                                                                   p = 0.486
    
                                                                                                                   Asthma, Ages 20-64,  Females: All
                                                                                                                   Periods: 1.052 (1.015-1.090)
                                                                                                                   Pre-Wldfire: 0.995 (0.904-1.096)
                                                                                                                   Wldfire: 1.064 (1.014-1.116), p = 0.247
                                                                                                                   Post-Wildfire: 0.908 (0.780-1.056),
                                                                                                                   p = 0.310
    
                                                                                                                   Asthma, Ages 65-99,  Males and
                                                                                                                   Females: All Periods: 1.027(0.974-
                                                                                                                   1.082)
                                                                                                                   Pre-Wldfire: 0.951 (0.849-1.064)
                                                                                                                   Wldfire: 1.101 (1.030-1.178), p = 0.032
                                                                                                                   Post-Wildfire: 1.168 (0.967-1.412),
                                                                                                                   p = 0.072
    
                                                                                                                   Asthma, Ages 65-99,  Males: All Periods:
                                                                                                                   1.046(0.957-1.142)
                                                                                                                   Pre-Wldfire: 0.948 (0.804-1.116)
                                                                                                                   Wldfire: 1.185  1.077-1.305), p = 0.029
                                                                                                                   Post-Wildfire: 0.902 (0.629-1.294),
                                                                                                                   p = 0.804
    
                                                                                                                   Asthma, Ages 65-99,  Females: All
                                                                                                                   Periods: 1.018 (0.958-1.081)
                                                                                                                   Pre-Wldfire: 0.947 (0.813-1.102)
                                                                                                                   Wldfire: 1.065 (0.977-1.162), p = 0.195
                                                                                                                   Post-Wildfire: 1.263 (1.024-1.557),
                                                                                                                   p = 0.032
    
                                                                                                                   Acute Bronchitis and  Bronchiolitis, All
                                                                                                                   Ages: All Periods: 1.044(0.990-1.102)
                                                                                                                   Pre-Wldfire: 1.001 (0.890-1.126)
                                                                                                                   Wldfire: 1.096 (1.018-1.179),
                                                                                                                   p = 0.223
                                                                                                                   Post-Wildfire: 1.031 (0.870-1.222),
                                                                                                                   p = 0.779
    
                                                                                                                   Acute Bronchitis and  Bronchiolitis, Ages
                                                                                                                   0-4: All Periods: 1.017 (0.949-1.089)
                                                                                                                   Pre-Wldfire: 0.987 (0.847-1.149)
                                                                                                                   Wldfire: 1.092 (0.997-1.195), p = 0.276
                                                                                                                   Post-Wildfire: 0.910 (0.700-1.183),
                                                                                                                   p = 0.588
                                                                                                                   Acute Bronchitis and  Bronchiolitis, Ages
                                                                                                                   5-19: No Convergence
    
                                                                                                                   Acute Bronchitis and  Bronchiolitis, Ages
                                                                                                                   20-64: All Periods: 1.039 (0.912-1.183)
                                                                                                                   Pre-Wldfire: 1.001 (0.792-1.266)
                                                                                                                   Wldfire: 1.044 (0.872-1.252), p = 0.778
                                                                                                                   Post-Wildfire: 1.259 (0.921-1.722),
                                                                                                                   p = 0.275
    
                                                                                                                   Acute Bronchitis and  Bronchiolitis, Ages
                                                                                                                   65-99: All Periods: 1.134 (1039-1.238)
                                                                                                                   Pre-Wldfire: 1.073 (0.764-1.505)
                                                                                                                   Wldfire: 1.143(1.032-1.265), p = 0.730
                                                                                                                   Post-Wildfire: 1.190 (0.865-1.638),
                                                                                                                   p = 0.652
    
                                                                                                                   COPD, Ages 20-99: All Periods: 1.018
                                                                                                                   (0.994-1.042)
                                                                                                                   Pre-Wldfire: 1.007 (0.958-1.058)
                                                                                                                   Wldfire: 1.038 (1.004-1.075), p = 0.320
               	Post-Wildfire: 1.024 (0.943-1.112),
    December 2009                                                     E-268
    

    -------
                Reference                     Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                  p = 0.728
    
                                                                                                                  COPD, Ages 20-64: All Periods: 1.022
                                                                                                                  (0.980-1.066)
                                                                                                                  Pre-Wildfire: 0.995 (0.916-1.081)
                                                                                                                  Wildfire: 1.068 (1.009-1.131), p = 0.161
                                                                                                                  Post-Wildfire: 1.015 (0.893-1.153),
                                                                                                                  p = 0.728
    
                                                                                                                  COPD, Ages 65-99: All Periods: 1.019
                                                                                                                  (0.992-1.048)
                                                                                                                  Pre-Wildfire: 1.014 (0.955-1.077)
                                                                                                                  Wildfire: 1.031 (0.990-1.074), p = 0.660
                                                                                                                  Post-Wildfire: 1.023 (0.928-1.128),
                                                                                                                  p = 0.878
    
                                                                                                                  Pneumonia, All Ages: All Periods: 1.009
                                                                                                                  (0.994-1.024)
                                                                                                                  Pre-Wildfire: 1.045 (0.931-1.180)
                                                                                                                  Wldfire: 1.028 (1.007-1.050), p = 0.420
                                                                                                                  Post-Wildfire: 0.980 (0.927-1.035),
                                                                                                                  p = 0.045
    
                                                                                                                  Pneumonia, Ages 0-4: All Periods:
                                                                                                                  0.995(0.944-1.049)
                                                                                                                  Pre-Wldfire: 1.048 (0.931-1.180)
                                                                                                                  Wldfire: 1.018 (0.948-1.092), p = 0.691
                                                                                                                  Post-Wildfire: 0.823 (0.649-1.044),
                                                                                                                  p = 0.089
    
                                                                                                                  Pneumonia, Ages 5-19: All Periods:
                                                                                                                  1.031  (0.966-1.098)
                                                                                                                  Pre-Wldfire: 1.017 (0.882-1.172)
                                                                                                                  Wldfire: 1.064 (0.990-1.142), p = 0.586
                                                                                                                  Post-Wildfire: 1.017 (0.767-1.349),
                                                                                                                  p = 0.998
    
                                                                                                                  Pneumonia, Ages 20-64: All Periods:
                                                                                                                  1.008(0.982-1.035)
                                                                                                                  Pre-Wldfire: 1.041 (0.982-1.104)
                                                                                                                  Wldfire: 1.032 (0.994-1.072), p = 0.823
                                                                                                                  Post-Wildfire: 1.013 (0.913-1.124),
                                                                                                                  p = 0.633
    
                                                                                                                  Pneumonia, Ages 65-99: All Periods:
                                                                                                                  1.011  (0.993-1.030)
                                                                                                                  Pre-Wldfire: 1.050 (1.006-1.097)
                                                                                                                  Wldfire: 1.029 (1.002-1.057), p = 0.445
                                                                                                                  Post-Wildfire: 0.985 (0.920-1.055),
                                                                                                                  p = 0.127
    
                                                                                                                  Relative Rate (Min Cl, Max Cl) in
                                                                                                                  relation to pre-wildfire period (1)
                                                                                                                  All Respiratory, All Ages: Wldfire,
                                                                                                                  unadjusted for PM25: 0.961 (0.916-
                                                                                                                  1.008)
                                                                                                                  Wldfire, adjusted for PM25: 0.903
                                                                                                                  (0.850-0.960)
                                                                                                                  Post-wildfire, unadjusted for PM25:
                                                                                                                  1.143(1.072-1.219)
                                                                                                                  Post-wildfire, adjusted for PM25:
                                                                                                                  1.173(1.097-1.253)
    
                                                                                                                  All Respiratory, Ages 0-4: Wldfire,
                                                                                                                  unadjusted for PM25:
                                                                                                                  0.865 (0.757-0.989)
                                                                                                                  Wldfire, adjusted for PM25:
                                                                                                                  0.842 (0.717-0.988)
                                                                                                                  Post-wildfire, unadjusted for PM25:
                                                                                                                  1.152(0.957-1.388)
                                                                                                                  Post-wildfire, adjusted for PM25:
                                                                                                                  1.162(0.954-1.415)
    
                                                                                                                  All Respiratory, Ages 5-19: Wldfire,
                                                                                                                  unadjusted for PM25:
                                                                                                                  1.098(0.901-1.324)
                                                                                                                  Wldfire, adjusted for PM25:
               	1.087(0.863-1.370)	
    December 2009                                                     E-269
    

    -------
                Reference                     Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.373(1.089-1.732)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.467(1.142-1.883)
    
                                                                                                                 All Respiratory, Ages 20-64: Wildfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 0.991 (0.922-1.066)
                                                                                                                 Wildfire, adjusted for PM25:
                                                                                                                 0.923(0.843-1.012)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.074(0.971-1.188)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.104(0.992-1.228)
    
                                                                                                                 All Respiratory, Ages 65-99: Wldfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 0.932(0.867-1.003)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 0.874 (0.795-0.959)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.147(1.045-1.259)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.193(1.084-1.313)
    
                                                                                                                 Asthma, All Ages: Wildfire, unadjusted
                                                                                                                 for PM25:1.088 (0.965-1.227)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 0.992(0.856-1.149)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.264(1.085-1.473)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.336(1.134-1.573)
    
                                                                                                                 Asthma, Ages 0-4: Wldfire, unadjusted
                                                                                                                 for PM25: 0.806 (0.632-1.029)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 1.282(0.958-1.716)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.092(1.759-1.572)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.133(0.777-1.654)
    
                                                                                                                 Asthma, Ages 5-19: Wldfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 1.254(0.999-1.575)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 1.282(0.958-1.716)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.564(1.160-2.109)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.629(1.184-2.243)
    
                                                                                                                 Asthma, Ages 20-64: Wldfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 1.273(1.067-1.518)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 1.221 (0.979-1.524)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.362(1.043-1.779)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.486(1.111-1.987)
    
                                                                                                                 Asthma, Ages 65-99: Wldfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 0.869(0.657-1.151)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 0.645 (0.450-0.925)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 0.924(0.606-1.408)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.005(0.650-1.552)
    
                                                                                                                 Acute Bronchitis and Bronchiolitis, All
                                                                                                                 Ages: Wldfire, unadjusted for PM25:
                                                                                                                 1.143(0.878-1.490)
                                                                                                                 Wldfire, adjusted for PM25:
               	0.959(0.696-1.321)	
    December 2009                                                     E-270
    

    -------
                Reference                     Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.482(1.042-2.109)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.580(1.089-2.291)
    
                                                                                                                 Acute Bronchitis and Bronchiolitis, Ages
                                                                                                                 0-4: Wildfire, unadjusted for PM25:
                                                                                                                 1.128(0.819-1.555)
                                                                                                                 Wildfire, adjusted for PM25:
                                                                                                                 0.899(0.607-1.333)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.520(0.947-2.440)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.547 (0.954-2.507)
    
                                                                                                                 Acute Bronchitis and Bronchiolitis,
                                                                                                                 Ages 5-19
                                                                                                                 No Correlation
    
                                                                                                                 Acute Bronchitis and Bronchiolitis,
                                                                                                                 Ages 20-64: Wldfire, unadjusted for
                                                                                                                 PM25:1.350 (0.688-2.648)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 1.320(0.608-2.863)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 2.454(1.068-5.640)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 2.515(1.055-5.998)
    
                                                                                                                 Acute Bronchitis and Bronchiolitis,
                                                                                                                 Ages 65-99: Wldfire, unadjusted for
                                                                                                                 PM25:1.166 (0.643-2.115)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 0.934 (0.422-20.66)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 0.911 (0.428-1.942)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 0.997 (0.439-2.262)
    
                                                                                                                 COPD, Ages 20-99: Wldfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 0.988(0.875-1.115)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 0.913(0.779-1.069)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.043(0.885-1.228)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.064(0.897-1.262)
    
                                                                                                                 COPD, Ages 20-64: Wldfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 0.967(0.779-1.201)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 0.873(0.660-1.156)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.175(0.862-1.601)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 1.311 (0.954-1.802)
    
                                                                                                                 COPD, Ages 65-99: Wldfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 1.002(0.869-1.156)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 0.926(0.767-1.117)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 0.985(0.811-1.196)
                                                                                                                 Post-wildfire, adjusted for PM25:
                                                                                                                 0.981 (0.798-1.206)
    
                                                                                                                 Pneumonia, All Ages: Wldfire,
                                                                                                                 unadjusted for PM25:
                                                                                                                 0.943(0.868-1.025)
                                                                                                                 Wldfire, adjusted for PM25:
                                                                                                                 0.888 (0.799-0.986)
                                                                                                                 Post-wildfire, unadjusted for PM25:
                                                                                                                 1.294(1.158-1.446)
                                                                                                                 Post-wildfire, adjusted for PM25:
               	1.318(1.174-1.479)	
    December 2009                                                    E-271
    

    -------
                Reference
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                  Pneumonia, Ages 0-4: Wildfire,
                                                                                                                  unadjusted for PM25:
                                                                                                                  0.938(0.705-1.247)
                                                                                                                  Wildfire, adjusted for PM25:
                                                                                                                  0.951 (0.678-1.333)
                                                                                                                  Post-wildfire,  unadjusted for PM25:
                                                                                                                  1.458(0.974-20182)
                                                                                                                  Post-wildfire,  adjusted for PM25:
                                                                                                                  1.374(0.885-2.133)
    
                                                                                                                  Pneumonia, Ages 5-19: Wldfire,
                                                                                                                  unadjusted for PM25:
                                                                                                                  0.891 (0.604-1.312)
                                                                                                                  Wldfire, adjusted for PM25:
                                                                                                                  0.830(0.541-1.272)
                                                                                                                  Post-wildfire,  unadjusted for PM25:
                                                                                                                  0.960(0.588-1.569)
                                                                                                                  Post-wildfire,  adjusted for PM25:
                                                                                                                  0.969(0.578-1.624)
    
                                                                                                                  Pneumonia, Ages 20-64: Wldfire,
                                                                                                                  unadjusted for PM25:
                                                                                                                  0.927(0.795-1.081)
                                                                                                                  Wldfire, adjusted for PM25:
                                                                                                                  0.837(0.690-1.016)
                                                                                                                  Post-wildfire,  unadjusted for PM25:
                                                                                                                  1.314(1.064-1.622)
                                                                                                                  Post-wildfire,  adjusted for PM25:1.300
                                                                                                                  (1.047-1.615)
    
                                                                                                                  Pneumonia, Ages 65-99: Wldfire,
                                                                                                                  unadjusted for PM25:
                                                                                                                  0.959(0.861-1.068)
                                                                                                                  Wldfire, adjusted for PM25:
                                                                                                                  0.899(1.782-1.033)
                                                                                                                  Post-wildfire,  unadjusted for PM25:
                                                                                                                  1.277(1.102-1.481)
                                                                                                                  Post-wildfire,  adjusted for PM25:
                                                                                                                  1.331 (1.142-1.552)	
    Reference: Dominici et al. (2006,
    Period of Study: 1999-2002
    
    Location: 204 U.S. counties, located
    in: Alabama, Alaska, Arizona, Arkansas,
    California, Colorado, Connecticut,
    Delaware, District of Columbia, Florida,
    Georgia, Hawaii, Idaho, Illinois, Indiana,
    Iowa, Kansas, Kentucky, Louisiana,
    Maine,  Maryland, Massachusetts,
    Michigan, Minnesota, Mississippi,
    Missouri,  Nevada,  New Hampshire,
    New Jersey, New Mexico, New York,
    North Carolina, Ohio, Oklahoma,
    Oregon, Pennsylvania, Rhode Island,
    South Carolina, Tennessee, Texas,
    Utah, Virginia, Washington, West
    Virginia, Wsconsin
    Outcome (ICD-9: Daily counts of
    hospital admissions for primary
    diagnosis of chronic obstructive
    pulmonary disease (490-492), and
    respiratory tract infections (464-466,
    480-487).
    
    Age Groups: >65 yr
    
    Study Design: Time series
    
    N: 11.5 million Medicare enrollees
    
    Statistical Analyses: Bayesian  2-stage
    hierarchical models.
    
    First stage: Poisson regression (county-
    specific)
    
    Second stage: Bayesian hierarchical
    models, to produce a national avg
    estimate
    
    Covariates: Day of the week,
    seasonality, temperature, dew point
    temperature, long-term trends
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package: R statistical
    software version 2.2.0
    
    Lags Considered: 0-2 days, avg of
    days 0-2
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean ftjg/m3) (IQR): 13.4 (11.3-15.2)
    
    Monitoring Stations: NR
    
    Copollutant (correlation): NR
    
    Other variables: Median of pain/vise
    correlations among PM25 monitors
    within the same county for 2000: r =
    0.91  (IQR: 0.81-0.95)
    PM Increment: 10 pg/m3 (Results in
    figures see notes)
    
    Percent increase in risk [95% PI]:
    COPD (Lag 0): Age 65+: 0.91 [0.18,
    1.64]
    
    Age 65-74: 0.42 [-0.64, 1.48]
    Age 75+:  1.47 [0.54, 2.40]
    
    Respiratory tract infection: Age 65+:
    0.92 [0.41,1.43]
    
    Age 65-74: 0.93 [0.04,  1.82]
    Age 75+:  0.92 [0.32, 1.53]
    
    Annual reduction in admissions
    attributable to a 10 pg/m3 reduction in
    daily PM25 level (95% PI):
    Cerebrovascular disease: Annual
    number of admissions: 226,641
    
    Annual reduction in admissions:  1836
    [680, 2992]
    
    COPD: Annual number of admissions:
    108,812
    
    Annual reduction in admissions:  990
    [196,1785]
    
    Respiratory tract infections: Annual
    number of admissions: 226,620
    
    Annual reduction in admissions:  2085
    [929, 3241]
    December 2009
                                     E-272
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Dominici et al. (2006,
    0883981
    Period of Study: 1999-2002
    Location: U.S. (mainland)
    Outcome (ICD-9): Respiratory tract
    infections (464-466, 480-487) and
    Chronic Obstructive Pulmonary Disease
    (490-492)
                                       Age Groups: All >65 yr
                                       65-74 yr
                                       >75yr
                                       Study Design: Time series
                                       N: 11.5 million at-risk
                                       Statistical Analyses: Bayesian 2-stage
                                       hierarchical models (day-to-day
                                       variation), Poisson regression (county-
                                       specific RRs)
                                       Covariates: Calendar time (seasonality
                                       and yr), temperature, dew point
                                       Season: NR
                                       Dose-response Investigated? No
                                       Statistical Package: NR
                                       Lags Considered: 0,1, 2 days
    Pollutant: PM25
    Averaging Time: Daily or every 3 days
    (depending on county)
    Mean: 13.4 (IQR: 11.3-15.2)
    Monitoring Stations: NR (used data
    from Air Quality System database)
    Copollutant: NR
    PM Increment: 10 pg/m
    Percentage Change in Hospital
    Admission Rates [PI]:
    COPD-Same day
    All >65: 0.91 [0.18,1.64]
    65-74 yr: 0.42 [-0.64,1.48]
    >75:1.47 [0.54,2.40]
    Respiratory Tract lnfections-2-day lag
    All >65: 0.92 [0.41,1.43]
    65-74 yr: 0.93 [0.04,1.82]
    >75:  0.92 [0.32,1.53]
    Notes: Other lag data shown in Fig 2-4
    Reference: Erbas et al. (2005, 0738491
    Period of Study: Jul 1989-Dec 1992
    Location: Melbourne, Australia
    Outcome (ICD):
    COPD (490-492, 494, 496)
    Asthma (493)
    Age Groups: NR
    Study Design: Time series
    N:NR
    Statistical Analyses: GLM, GAM,
    Parameter Driven Poisson Regression,
    Transitional Regression, Seasonal-
    Trend decomposition based on Loess
    smoothing for seasonal adjustment
    Covariates: Secular trends,
    seasonality, relative humidity, dry bulb
    temp, dew point temp
    Season: NR
    Dose-response Investigated? Yes
    Statistical Package: S-Plus, SAS
    Lags Considered: 0-5 days
    Pollutant: PMO.1-1 (API)
    Averaging Time: 24 h
    Mean (min-max): NR
    Monitoring Stations: 9
    Copollutant (correlation): NR
    PM Increment: Increase from the
    10th-90thpercentile (value NR)
    RR Estimate [Cl]:
    COPD
    GAM:
    0.95 [0.91,1.00]
    GLM, PDM, TRM:NR
    Asthma
    NR
    Notes: This study was used to
    demonstrate that conclusions are highly
    dependent on the type of model used
    December 2009
                                    E-273
    

    -------
    Reference
    Reference: Fung et al. (2006, 0897891
    Period of Study: Jun 1995-Mar 1999
    Location: Vancouver, Canada
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Hinwood et al. (2006,
    Design & Methods
    Hospital Admission/ED:
    Hospital Admission
    Outcome: Respiratory diseases
    (460-519)
    
    Age Groups: Age >65
    Study Design: Time series, case
    crossover
    
    N: 26,275 individuals admitted
    
    Statistical Analyses: Poisson
    regression (spline 12 knots), case-
    crossover (controls +17 days from case
    date), Dewanji and Moolgavkar (DM)
    method
    
    Covariates: Long-term trends, day-of-
    the-week effect, weather
    
    Season: All yr
    
    Dose-response Investigated? No
    Statistical Package: SPIus, R
    Lags Considered: 0-7 days
    
    
    
    
    Hospital Admission
    Concentrations1
    Pollutant: PM25
    Averaging Time: 24-h avg
    Mean (SD): 7.72(3.61)
    
    Range (Mm, Max): (2, 32)
    Monitoring Stations: NR
    Copollutant (correlation):
    PM25:
    
    PM10r = 0.80
    
    PMio-25 r = 0.34
    rn r - n 9?
    **s\J 1 ~ U.ZO
    CoH r = 0.38
    
    03r = -0.03
    
    N02r = 0.36
    
    S02r = 0.42
    
    
    
    
    
    
    
    Pollutant: PM25
    Effect Estimates (95% Cl)
    PM Increment: : 4 pg/m3
    RR Estimate (66+ yr)
    DM method:
    
    1.007(0.994, 1.020]
    Current
    1.007[0.990,1.023]3day
    
    0.995[0.979,1.012]5day
    
    0.995(0.971, 1.020] 7 day
    Tirnp cpripc1
    I II 1 1C oCI ICo.
    1.003(0.989, 1.018]
    
    Current
    
    1.000(0.982, 1.018] 3 day
    
    0.993(0.972, 1.014] 5 day
    
    0.995(0.971, 1.020] 7 day
    Case-crossover:
    1.002(0.986, 1.019]
    Current
    1.001(0.981, 1.021] 3 day
    0.988(0.966, 1.011] 5 day
    0.984(0.959, 1.010] 7 day
    Increment: 1 pg/m3
    088976'
    
    Period of Study: Jan 1992-Dec 1998
    
    Location: Perth, Australia
    Outcome (ICD-9): COPD (490-496.99,
    except asthma), pneumonia /influenza
    (480-489.99), asthma
    
    Age Groups: All ages
    
    Study Design: Time stratified case-
    crossover
    
    N:NR
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Time trend, season,
    temperature, humidity, dayofwk,
    holidays
    
    Season: All yr
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 0-3 days
    Averaging Time: 24-h avg
    
    Mean (SD): 9.2 (4.3)
    
    Percent! les:
    
    10th: 5.0
    
    90th: 14.5
    
    Monitoring Stations: 13
    
    Notes: Copollutant: NR
    Notes: Odds ratio for PM25 and all
    respiratory, COPD, pneumonia and
    asthma. Authors found an elevation in
    the odds ratio for lags 2 and 3
    reaaching significance in all age groups
    for lag 3. For each increase of 1 pg/m ,
    the number of hospitalizations
    increases 0.2% for respiratory disease,
    0.5% for pneumonia and 0.3% for
    asthna. PM25 concentrations were also
    significantly associated with asthma for
    those aged under 15 yrwith an
    estimated 0.5% increase in
    hospitalizations.
    December 2009
                                    E-274
    

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                Reference
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Hirshon et al. (2008,
    1803751
    Period of Study: Jun 2002-Nov 2002
    
    Location: Baltimore, Maryland
    Outcome: Hospital admissions for
    asthma
    
    Study Design: Time-series
    
    Covariates: Spatial distance from
    pollution monitor, demographic
    variation, long term, seasonal and daily
    trends, weather and other pollutants
    
    Statistical Analysis: Overdispersed
    Poisson regression
    
    Age Groups: 0-17 yr
    Pollutant: Plfezinc
    
    Averaging Time: 24 h
    
    Mean (SD) Unit: 22.42 (25.14) pg/m3
    
    Range (Min, Max): NR
    
    Copollutant (correlation):
    
    Ni:0.41
    
    Cr:0.17
    
    Fe: 0.54
    
    Sulfate: 0.01
    
    CO: 0.40
    
    PM25: 0.39
    
    03: 0.01
    
    N02: 0.66
    
    EC: 0.48
    Increment: NR
    
    Relative Risk (96% Cl), Best fit Model
    Medium = 8.63-20.76 ng/m3
    High = >20.76 ng/m3
    No Lag
    Medium: 1.12 (0.98-1.28)
    High: 1.09 (0.91-1.30)
    1-day Lag
    Medium: 1.23 (1.07-1.41)
    High: 1.16 (0.97-1.39)
    2-day Lag
    Medium: 1.11 (0.94-1.30)
    High: 1.15 (0.96-1.38)
    Controlling for Time Trends
    No Lag
    Medium: 1.08 (0.95-1.23)
    High: 0.98 (0.86-1.11)
    1-day Lag
    Medium: 1.13 (1.003-1.28)
    High: 1.03 (0.91-1.16)
    2-day Lag
    Medium:! 13 ()
    High: 0.98-1.31
    Controlling for Time Trends and
    Additional  Copollutants
    No Lag
    Medium: 1.12 (0.98-1.29)
    High: 1.09 (1.01-1.30)
    1-day Lag
    Medium: 1.20 (1.04-1.38)
    High: 1.12 (0.93-1.35)
    2-day Lag
    Medium: 1.12 (0.95-1.32)
    High: 1.19 (0.98-1.44)	
    Reference: Host et al. (2007,1558511
    
    Period of Study: 2000-2003
    
    Location: Six French cities: Le Havre,
    Lille, Marseille, Paris, Rouen, and
    Toulouse
    Outcome (ICD-10): Daily
    hospitalizations for all respiratory
    diseases (JOO-J99), respiratory
    infections (J10-J22).
    
    Age Groups: For all respiratory
    diseases: 0-14 yr, 15-64 yr, and > 65 yr.
    
    For respiratory infections: All ages
    
    Study Design: Time series
    
    N: NR (Total population of cities:
    approximately 10 million)
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Seasons, days of the
    week, holidays, influenza epidemics,
    pollen counts, temperature, and
    temporal trends
    
    Season: NR
    
    Dose-response Investigated: No
    
    Statistical Package:  MGCV package in
    R software (R 2.1.1)
    
    Lags Considered: Avg of 0-1 days
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (6th -96th percentile):
    Le Havre:  13.8 (6.0-30.5)
    
    Lille: 15.9 (6.9-26.3)
    
    Marseille: 18.8 (8.0-33.0)
    
    Paris: 14.7 (6.5-28.8)
    
    Rouen: 14.4 (7.5-28.0)
    
    Toulouse: 13.8 (6.0-25.0)
    
    Monitoring Stations:
    13 total: 1  in Toulouse
    
    4 in Paris
    
    2 each in other cities
    
    Copollutant (correlation):
    PMio.25: Overall: r> 0.6
    
    Ranged between r = 0.28 and
    
    r = 0.73 across the six cities.
    PM Increment: 10 pg/m  increase, and
    a 27 pg/m3 increase (corresponding to
    the difference between the lowest of the
    5th percentiles and the highest of the
    95th percentiles of the cities'
    distributions)
    
    ERR (excess relative risk) Estimate [Cl]:
    For all respiratory diseases  (27 pg/m
    increase): 0-14 yr: 1.1% [-3.1, 5.5]
    
    15-64 yr: 2.2% [-1.8, 6.4];
    
    > 65 yr:  1.3% [-5.3, 8.2]
    
    For respiratory infections (10 pg/m3
    increase): All ages: 2.5% [0.1, 4.8]
                                                                                                                  For respiratory infections
                                                                                                                  increase): All ages: 7.0%
                           27 pg/m3
                           0.7,13.6]
    December 2009
                                     E-275
    

    -------
    Reference
    Reference: Ko et al. (2007, 0916391
    Period of Study: Jan 2000-Dec 2004
    Location: Hong Kong, China
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Ko et al. (2007, 0928441
    Period of Study: Jan 2000-Dec 2005
    Location: Hong Kong, China
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Lee et al. (2006, 0901761
    Period of Study: Jan 1997-Dec 2002
    Location: Hong Kong, China
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    ED Visits
    Outcome (ICD-9): COPD: Chronic
    bronchitis (491), Emphysema (492),
    Chronic airway obstruction (496)
    Age Groups: All ages
    Study Design: Time series
    
    N: 15 hospitals, 11 9,225 admissions
    Statistical Analyses: Poisson
    regression, GAM with stringent
    convergence criteria, APHEA2 protocol.
    Covariates: Time trend, season,
    temperature, humidity, other cyclical
    factors, day, dayofwk, holidays
    Season: All yr, interactions with season
    tested
    
    Dose-response Investigated? No
    
    Statistical Package: SPLUS 4.0
    
    Lags Considered: 0-5 days
    Hospital Admission
    Outcome (ICD-9): Asthma (493)
    Age Groups: All, 0-14, 15-56,65+
    Study Design: Time series
    
    N: 69,716 admissions, 15 hospitals
    
    Statistical Analyses: Poisson
    regression, with GAM with stringent
    convergence criteria.
    Covariates: Time trend, season,
    temperature, humidity, other cyclical
    factors
    Season: All yr, evaluated effect of
    season in analysis
    
    Dose-response Investigated? No
    Statistical Package: SPLUS 4.0
    Lags Considered: 0-5 days
    Hospital Admission
    Outcome: Asthma (493)
    Age Groups: <18yr
    Study Design: Time series
    N: 26,663 asthma admissions for
    asthma and 5821 admissions for
    influenza
    Statistical Analyses: Poisson
    regression, GAM
    Covariates: Temperature, atmospheric
    pressure, relative humidity
    Season: All
    Dose-response Investigated? No
    Statistical Package: SAS 8.02
    Lags Considered: 0-5
    Notes: Controls were admissions for
    influenza ICD9 487
    Concentrations1
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 35.7 (20.6)
    Percent! les:
    25th: 19.4
    
    50th(Median):31.7
    75th: 46.7
    Range (Min, Max): (6.0, 163.2)
    Monitoring Stations: 14
    Copollutant (correlation):
    PM25:
    PM,0r = 0.952
    
    N02r = 0.441
    
    03r = 0.394
    
    S02 r = 0.282
    
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 36.4 (21.1)
    Percent! les:
    
    25th: 20.0
    
    SOth(Median): 32.5
    75th: 47.7
    Range (Min, Max): (6, 163)
    Monitoring Stations: 14
    Copollutant (correlation):
    PM25:
    PM,o r = 0.956
    N02 r = 0.774
    03 r = 0.585
    S02 r = 0.482
    
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (SD): 45.3 pg/m3, (16.2)
    Percentiles: 25th: 33.4
    SOth(Median): 43.0
    
    75th: 54.0
    Range (Min, Max): NR
    Monitoring Stations: 10
    Copollutant (correlation):
    PM25-PM10: 0.89
    PM25-S02: 0.48
    PM25-N02: 0.74
    PM25-03: 0.47
    
    
    Effect Estimates (95% Cl)
    PM Increment: PMi0
    RR Estimate
    COPD:
    1.0020.998, 1.001 lagO
    1.0030.999, 1.007 lag 1
    1.0111.007, 1.014] lag 2
    1.0131.010,1.017 Iag3
    1.011 1.008, 1.015] lag 4
    1.0091.006,1.013 Iag5
    1.0040.999, 1.008 lag 0-1
    1.0101.006, 1.015 lag 0-2
    1.0181.013, 1.022 lag 0-3
    1.0241.019, 1.029 lag 0-4
    1.031 1.026, 1.036 lag 0-5
    4-Pollutant model:
    1.014(1.007, 1.022] lag 0-5
    3-Pollutant model:
    1.011(1.004, 1.017] lag 0-5
    
    
    
    
    
    
    PM Increment: 10.0 pg/m3
    RR Estimate
    Asthma (Single-pollutant model):
    1.0081.004,1.013 lagO
    1.0041.000,1.009 Iag1
    1.0041.000, 1.009 lag 2
    1.0091.005, 1.014 Iag3
    1.006 1.001, 1.011] lag 4
    1.0020.998! 1.007 lag 5
    1.0091.004 1.014 lag 0-1
    1.0121.007,1.018 lag 0-2
    1.0171.011, 1.022] lag 0-3
    1.020 1.014, 1.026 lag 0-4
    1.021 1.015,1.028 lag 0-5
    Asthma in Age:
    0-14: 1.024(1. 013, 1.034] lag 0-5
    14-65:1.018(1.008, 1.029] lag 0-5
    >65: 1.021(1. 012, 1.030] lag 0-4
    Asthma-Cold Season:
    1.139(1.043, 1.244] lag 0-5
    PM Increment: IQr= 20.6 pg/m3
    Percent increase:
    Single pollutant model:
    5.10(2.95, 7.30], lag 0
    5.00(2.88, 7.16], lag 1
    
    5.48 [2.75, 6.95], lag 2
    4.83 [2.78, 6.93], lag 3
    6.59 [4.51, 8.72], lag 4
    5.24 [3.18, 7.34], lag 5
    Multipollutant model (S02, N02, CO, 03)
    3.24 [0.93, 5.60], lag 4
    
    
    
    
    December 2009
    E-276
    

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                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Letz and Quinn (2005,
    0887521
    Period of Study: Oct 2001-Aug 2002
    Location: San Antonio,Texas
    Emergency Dept Visits
    Outcome (ICD-9): Asthma or reactive
    airway disease (493.0-493.9), wheezing
    (786.07), dyspnea (786.01-786.9),
    shortness of breath (786.05), bronchitis
    (490-496),  or cough (786.2)
    Age Groups: NR (basic air force
    trainees)
    Study Design: Historic (retrospective)
    cohort
    N: 149 ED visits
    Statistical Analyses: Pearson
    correlation
    Covariates: NR
    Season: NR
    Dose-response  Investigated? No
    Statistical Package: SPSS
    Lags Considered: NR
    Pollutant: PM25
    Averaging Time: 24-h AQI
    AQI Range (min-max): (4-109)
    Monitoring Stations: Data obtained
    from the Texas Commission on
    Environmental Quality
    Copollutant (correlation): NR
                                        N: 6782 respiratory infection
                                        hospitalizations
                                        Statistical Analyses: Conditional
                                        logistic regression (Cox proportional
                                        hazards model)
                                        Covariates: Daily mean temp and dew
                                        point temp
                                        Season: NR
                                        Dose-response Investigated? No
                                        Statistical Package: SAS 8.2 PHREG
                                        procedure
                                        Lags Considered: 1- to 7-day avg
                                        Copollutant (correlation):
                                        PM10.25:r = 0.33
                                        PM10:r = 0.87
                                        CO: r = 0.10
                                        S02:r = 0.47
                                        N02:r = 0.48
                                        03:r = 0.56
    PM Increment: NR
    Correlation with Outcomes:
    Same-day
    All visits: r = 0.082
    Proven asthmatic events: r = -0.042
    3-day
    All visits: r = 0.097
    Proven asthmatic events: r = 0.011
    Reference: Lin et al. (2005, 0878281
    Period of Study: 1998-2001
    Location: Toronto, North York, East
    York, Etobicoke, Scarborough, and York
    (Canada)
    Hospital Admissions
    Outcome (ICD-9): Respiratory
    infections including laryngitis, tracheitis,
    bronchitis, bronchiolitis, pneumonia,
    and influenza (464, 466, 480-487)
    Age Groups: 0-14 yr
    Study Design: Bidirectional case-
    crossover
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (min-max):
    9.59 (0.25-50.50)
    SD = 7.06
    Monitoring Stations: 4
    PM Increment: 7.8 pg/m3
    OR Estimate [Cl]:
    Adjusted for weather
    4-day avg: 1.11 [1.02,1.22]
    6-day avg: 1.11 [1.00,1.24]
    Adj for weather and other gaseous
                                        4-day avg: 0.94 [0.81,1.08]
                                        6-day avg: 0.90 [0.76,1.07]
                                        Notes: OR's were also categorized into
                                        "Boys" and "Girls," yielding similar
                                        results
    December 2009
                                    E-277
    

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                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Lin et al. (2002, 0260671
    Period of Study: Jan 1981-Dec 1993
    Location: Toronto
    Hospital Admissions
    Outcome (ICD-9): Asthma (493)
    Age Groups: 6-12 yr
    Study Design: Uni- and bi-directional
    case-crossover (UCC, BCC) and time-
    series (TS)
    N: 7,319 asthma admissions
    Statistical Analyses: Conditional
    logistic regression, GAM
    Covariates: Maximum and minimum
    temp, avg relative humidity
    Season: Apr-Sep, Oct-Mar
    Dose-response  Investigated? No
    Statistical Package: NR
    Lags Considered: 1- to 7-day avg
    Pollutant: PM25
    Averaging Time: 6 days (predicted
    daily values)
    Mean (min-max):
    17.99(1.22-89.59)
    SD = 8.49
    Monitoring Stations: 1
    Copollutant (correlation):
    PM,o:r = 0.87
    PMi0.25:r = 0.44
    CO: r = 0.45
    S02:r = 0.46
    N02:r = 0.50
    03:r = 0.21
    PM Increment: 9.3 pg/m
    RR Estimate [Cl]:
    Adj for weather and gaseous pollutants
    BCC 5-day avg: 0.94 [0.85,1.03]
    BCC 6-day avg: 0.92 [0.83,1.02]
    TS 5-day avg: 0.96 [0.90,1.02]
    TS 6-day avg: 0.94 [0.88,1.01]
    Boys-adj for weather
                                                                                                                                 '1.04,1.15
                                                                                                                                 1.02,1.16
                                                                                                                                 0.97,1.06'
                                                                                                                                 0.93,1.05:
                                                                                                              TS 1-day avg: 1.00 [0.97,1.04]
                                                                                                              TS 2-day avg: 0.98 [0.94,1.02]
                                                                                                              Girls-adj for weather
    UCC 1-day avg: 1.09
    UCC 2-day avg: 1.09
    BCC 1-day avg: 1.01
    BCC 2-day avg: 0.99
                                                                                                              UCC 1-day avg: 1.06
                                                                                                              UCC 2-day avg: 1.11
                                                                                                              BCC 1-day avg: 0.99
                                                                                                              BCC 2-day avg: 1.02
                       0.99,1.14
                       1.02,1.21'
                       0.93,1.06:
                       0.94,1.09:
                     o:95,1.04] '
                     0.95,1.06]
                                                                                                              TS 1-day avg: 0.99
                                                                                                              TS 2-day avg: 1.00
                                                                                                              Notes: The author also provides RR
                                                                                                              using UCC, BCC, and TS analysis for
                                                                                                              female and male groups for days 3-7,
                                                                                                              yielding similar results
    Reference: Magas et al. (2007,
    0907141
    Period of Study: 2001-2003
    Location: Oklahoma City Metro area,
    Oklahoma and Cleveland counties
    Hospital Admission/ED: Admissions
    Outcome: Asthma 493.01-493.99
    Age Groups: <1 Syr
    Study Design: Time series
    N: 1,270 admissions
    Statistical Analyses: Negative
    binomial regression
    Covariates: Temperature, humidity,
    pollen count, mold
    Season: All
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: 1
    Pollutant: PM25
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (Min, Max): NR
    Monitoring Stations: 10
    Copollutant (correlation): NR
    Notes: Coefficient for PM25 was not
    significant and thus not reported.
    Reference: Mohr et al. (2008,1802151
    Period of Study: Jun 2001-May 2003
    Location: St. Louis, MO
    Outcome: Asthma ER Visits
    Age Groups: 2-17 yr
    Study Design: Time series
    Statistical Analyses: GEE Poisson
    models
    Covariates: Season, weekend
    exposure, allergens
    Dose-response Investigated: No
    Statistical Package: SAS
    Lags Considered: 1 day
    Pollutant: PM25 EC
    Averaging Time: 24 h
    StdDev:0.1
    Monitoring Stations: 1
    Copollutant: NOX, S02, 03
    Co-pollutant Correlation
    NOX: 0.68*
    S02: 0.09
    03: -0 06
    *p<0.05
    PM Increment: 0.1 pg/m
    Relative Risk Effect (Lower Cl, Upper
    Cl):
    Weekend Exposure
    Summer:  1.05 (1.00,1.11)
    Fall: 0.99 (0.97, 1.01)
    Winter: 0.96 (0.92,1.00)
    Spring: 0.96 (0.92,1.00)
    Weekday Exposure
    Summer:  1.01 (0.98,1.03)
    Fall: 1.00 (0.99,1.01)
    Wnter: 0.99 (0.96,1.01)
    Spring: 0.98 (0.96,1.01)
    December 2009
                                    E-278
    

    -------
                Reference
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Neuberger et al. (2004,
    0932491
    Period of Study: 1999-2000 (1-yr
    period)
    
    Location: Vienna and Lower Austria
    Hospital Admissions
    
    Outcome (ICD-9): Bronchitis,
    emphysema, asthma, bronchiectasis,
    extrinsic allergic alveolitis, and chronic
    airway obstruction (490-496)
    
    Age Groups: 3.0-5.9 yr
    7-10 yr
    65+yr
    
    Study Design: Time series
    
    N: 366 days (admissions NR)
    
    Statistical Analyses: GAM
    
    Covariates: S02, NO, N02, 03,
    temperature, humidity, and day of the
    week
    
    Season: NR
    
    Dose-response Investigated? Yes
    
    Statistical Package: S-Plus 2000
    
    Lags Considered: 0-14 days
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Maximum daily mean:
    
    Vienna: 96.4
    
    Rural area: 48.0
    
    Monitoring Stations: NR
    
    Copollutant (correlation): NR
    PM Increment: 10 pg/m
    
    Log Relative Rate Estimate (p-value):
    
    Vienna
    Male: 2-day lag = 5.467 (0.019)
    Female: 3-day lag = 5.596 (0.009)
    
    Rural
    Male: 10-day lag = 9.893 (0.012)
    Female: 11-day lag = 10.529 (0.011)
    
    Association with tidal lung functioN:
    P = -0.987 (p-value = 0.091)
    
    Notes: Effect parameters with
    significant coefficients for respiratory
    health included: male sex, allergy,
    asthma in family, and traffic for Vienna
    and age, allergy, asthma in family,
    passive smoking,  and PM fraction for
    the rural area. Effect parameters with
    significant coefficients for log asthma
    score were allergy, asthma in family,
    and rain for Vienna and allergy, asthma
    in family, and passive smoking for the
    rural area. Cross-correlation coefficients
    are provided in Fig 1.
    Reference: Ostro et al. (2008, 0979711
    
    Period of Study: 2000-2003
    
    Location: Six California Counties
    Outcome: Respiratory disease
    (ICD-9 460-519)
    
    Study Design: Time-Series
    
    Statistical Analysis: Poisson
    Regression
    
    Statistical Package: R
    
    Age Groups: Children <19 yr
    Pollutant: PM25 and components
    
    Averaging Time: 24 h
    
    Mean (SD) Unit: 19.4 pg/m3
    
    IQR: 14.6 pg/m3
    
    Copollutants:
    
    EC, OC, N02, S04, Cu, Fe,  K, Si, Zn
    Increment: NR
    
    Relative Risk (Min Cl, Max Cl)
                                                                                                                 Full results are presented graphically in
                                                                                                                 figures 1 and 2.
    
                                                                                                                 Excess risks for all-yr respiratory
                                                                                                                 hospital admissions in children <19yrs,
                                                                                                                 3-day lag
                                                                                                                 PM25: 4.1% (1.8-6.4)
                                                                                                                 EC: 5.4% (0.8-10.3)
                                                                                                                 Fe: 4.7% (2.2-7.2)
                                                                                                                 OC: 3.4% (1.1-5.7)
                                                                                                                 Nitrates: 3.3% (1.1-5.5)
                                                                                                                 Sulfates: 3.0% (0.4-5.7)
                                                                                                                 Excess risks for cool season (Oct-Mar)
                                                                                                                 respiratory hospital admissions in
                                                                                                                 children <19yrs, 3 day lag
                                                                                                                 PM25: 5.1% (1.6-8.9)
                                                                                                                 EC: 6.8% (-0.2-14.2)
                                                                                                                 Fe: 4.8% (1.7-8.0)
                                                                                                                 K: 4.0% (0.3-7.7)	
    December 2009
                                     E-279
    

    -------
               Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Slaughter et al. (2005,
    0738541
    Period of Study: Jan 1995-Jun 2001
    
    Location: Spokane, WA
    Hospital Admissions and ED visits
    
    Outcome: All respiratory (460-519)
    Asthma (493)
    COPD (491,492, 494,496)
    Pneumonia (480-487)
    Acute URI not including colds and
    sinusitis (464, 466, 490)
    
    Age Groups: All, 15+ yr for COPD
    
    Study Design: Time series
    
    N: 2373 visit records
    
    Statistical Analyses: Poisson
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Range (90% of Concentrations):
    
    4.2-20.2 pg/m3
    
    Monitoring Stations:
    
    One
    
    Notes: Copollutant (correlation):
    PM2.5
    
    PM1 r = 0.95
    PM Increment: 10 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    ER visits:
    PM25
    All Respiratory
    Lag 1:1.01 [0.98,1.04]
    Lag 2:1.02 [0.99,1.04]
    Lag 3:1.02 [0.99,1.05]
    Acute Asthma
    Lag 1:1.03 [0.98,1.09]
    Lag 2:1.00 [0.95,1.05]
    Lag 3:1.01 [0.96,1.06]
    COPD (adult)
    
    
    
    
    
    
    
    
    
    
    
    Reference: Tecer et al. (2008, 1800301
    Period of Study: Dec 2004-Oct 2005
    Location: Zonguldak, Turkey
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Tolbert et al. (2007,
    0903161
    
    Period of Study: Aug 1998-Dec 2004
    Location: Atlanta Metropolitan area,
    Georgia
    
    
    
    
    regression, GLM with natural splines.
    For comparison also used GAM with
    smoothing splines and default
    convergence criteria.
    Covariates: Season, temperature,
    relative humidity, day of week
    Season: All
    
    Dose-response Investigated?: No
    Statistical Package: SAS, SPLUS
    Lags Considered: 1 -3 days
    
    
    
    Outcome: ED visits for respiratory
    problems (ICD-9 470-478, 493)
    Study Design: Bidirectional Case-
    crossover
    Covariates: Daily meteorological
    parameters
    Statistical Analysis: Conditional
    logistic regression
    
    Statistical Package: Stata
    Age Groups: 0-14 yr
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome (ICD-9):
    
    Combined RD group, including:
    Asthma (493, 786.07, 786.09), COPD
    (491, 492, 496), URI (460-465, 460.0,
    477), pneumonia (480-486), and
    bronchiolitis (466.1, 466. 11, and
    400. iyjj
    Age Groups: All
    
    PM10r = 0.62
    PM10.25r = 0.31
    CO r = 0.62
    Temperature r = 0.21
    
    
    
    
    
    
    
    
    Pollutant: PM25
    Averaging Time: NR
    Mean, Unit: 29.1 pg/m3
    Range (Min, Max): 4.55, 95.65
    Copollutant (correlation):
    PM25/PM10
    Mparv D ^fi
    ivicai i. u.uu
    Range: 0.17-0. 88
    PM2,/PM10.2,
    
    Mean: 1.49
    Range: 0.21-7.53
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM25
    
    Averaging Time: 24 h
    Mean (median IQR, range, 10th-90th
    percentiles):
    PM25' 17 1 (156
    11.0-21.9
    0.8-65.8
    7.9-28.8)
    PM25sulfate:4.9(3.9
    2.4-6.2
    Lag 1:0. 96
    Lag 2: 1.01
    Lag 3: 1.00
    Hospital Ac
    0.89, 1.04]
    0.93, 1.09]
    0.93, 1.08]
    missions:
    PM25
    All Respiratory
    Lag 1:0.98 [0.94, 1.01]
    Lag 2: 0.99 [0.96, 1.03]
    Lag 3: 1.01 [0.98, 1.05]
    Asthma
    Lag 1:1. 01 [0.91, 1.11]
    Lag 2: 1.03 [0.94, 1.13]
    Lag 3: 1.02 [0.93, 1.13]
    COPD (adult)
    Lag 1:0.99 [0.91, 1.08]
    Lag 2: 1.06 [0.98, 1.16]
    Lag 3: 1.03 [0.94, 1.12]
    Increment: 10 pg/m3
    Odds Ratio (96% Cl)
    Asthma
    Lag 0:1. 15 0.99-1.34)
    Lag 1:0.85
    Lag 2: 0.87
    Lag 3: 0.93
    Lag 4: 1.25
    Allergic Rhir
    LagO: 1.21
    Lag 1:0.84
    0.70-1.03)
    0.73-1.04)
    0.79-1.10)
    1.05-1.50)
    itis with Asthma
    1.10-1.33)
    0.75-0.93)
    Lag 2: 0.89 (0.81-0.98)
    Lag 3: 0.99 0.90-1.09)
    Lag 4: 1.06
    0.95-1.19)
    Allergic Rhinitis
    Lag 0:1. 08
    Lag 1:1. 03
    Lag 2: 0.89
    Lag 3: 0.98
    Lag 4: 1.18
    0.98-1.20)
    0.93-1.13)
    0.80-0.99)
    0.89-1.09)
    1.00-1.24)
    Upper Respiratory Disease
    Lag 0: 0.99
    Lag 1:0.52
    0.49-2.00)
    0.22-1.20)
    Lag 2: 1.29 (0.75-2.22)
    Lag 3: 1.29
    Lag 4: 1.47
    0.69-2.43)
    0.87-2.50)
    Lower Respiratory Disease
    Lag 0:1. 06
    Lag 1:0.85
    0.78-1.44)
    0.59-1.22)
    Lag 2: 1.08 (0.72-1.61)
    Lag 3: 1.18
    Lag 4: 0.72
    0.92-1.52)
    0.54-0.96)h
    PM Increment:
    
    PM25: 10.96 pg/m3 (IQR)
    PM25sulfate:3.82pg/m3(IQR)
    PM2.5 total carbon: 3.63 pg/m3 (IQR)
    PM25OC:2.61 pg/m3 (IQR)
    
    PM2 5 EC: 1.1 5 pg/m3 (IQR)
    PM2 5 water-soluble metals: 0.03 pg/m3
    December 2009
                                   E-280
    

    -------
               Reference
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                      Study Design: Time series
    
                                      N:NR for 1998-2004.
    
                                      For 1993-2004:10,234,490 ER visits
                                      (283,360 and 1,072,429 visits included
                                      in the CVD and RD groups,
                                      respectively)
    
                                      Statistical Analyses: Poisson
                                      generalized linear models
    
                                      Covariates: Long-term temporal
                                      trends, season (for RD outcome),
                                      temperature, dew point, days of week,
                                      federal holidays, hospital entry and exit
    
                                      Season: All
    
                                      Dose-response Investigated: No
    
                                      Statistical Package: SAS version 9.1
    
                                      Lags Considered: 3-day ma(lag 0 -2)
                               0.5-21.9
                               1.7-9.5)
                               PM25OC:4.4(3.8
                               2.7-5.3
                               0.4-25.9
                               2.1-7.2)
                               PM25EC:1.6(1.3
                               0.9-2.0
                               0.1-11.9
                               0.6-3.0)
                               PM2 5 water-soluble metals: 0.030
                               (0.023
                               0.014-0.039
                               0.003-0.202
                               0.009-0.059)
                               Monitoring Stations: 1
                               Copollutant (correlation): Between
                               PM25and:
                               PM10:r = 0.84
                               03:r = 0.62
                               N02:r = 0.47
                               CO: r = 0.47
                               S02:r = 0.17
                               PMi0.25:r = 0.47;
                               PM25S04:r = 0.76;
                               PM25EC:r = 0.65;
                               PM25OC:r = 0.70;
                               PM25TC:r = 0.71;
                               PM2 5 water-sol metals:
                               r = 0.69
                               OHC:r = 0.50
                               Between PM25 S04 and: PMi0: r = 0.69
                               03:r = 0.56
                               N02:r = 0.14
                               CO: r = 0.14
                               S02:r = 0.09
                               PM10.25:r = 0.32;
                               PM25:r = 0.76;
                               PM25EC:r = 0.32;
                               PM25OC:r = 0.33;
                               PM25TC:r = 0.34;
                               PM2 5 water-sol metals:
                               r = 0.65
                               OHC:r = 0.47
                               Between PM25ECand: PM10: r = 0.61
                               03:r = 0.40
                               N02:r = 0.64
                               CO: r = 0.66
                               S02:r = 0.22
                               PMi0.25:r = 0.49
                               PM25:r = 0.65
                               PM25S04:r = 0.32
                               PM25OC:r = 0.82
                               PM25TC:r = 0.91
                               PM2 5 water soluble metals: r = 0.52
                               OHC:r = 0.35
                               Between PM25OCand: PM10: r = 0.65
                               03:r = 0.54
                               N02:r = 0.62
                               CO: r = 0.59
                               S02:r = 0.17
                               PMi0.25:r = 0.49
                               PM25:r = 0.70
                               PM25S04:r = 0.33
                               PM25EC:r = 0.82
                               PM25TC:r = 0.98
                               PM2 5 water-sol metals:
                               r = 0.49
                               OHC:r = 0.37
                               Between PM25 total carbon and: PM10: r
                               = 0.67
                               03:r = 0.52
                               N02:r = 0.65
                               CO: r = 0.63
                               S02:r = 0.19
                               PM10.25:r = 0.51
                               PM25:r = 0.71	
                              (IQR)
    
                              Risk ratio [95% Cl] (single pollutant
                              models):
    
                              PM25:
    
                              RD: 1.005 [0.995-1.015]
    
                              PM2 5 sulfate:
    
                              RD: 1.007 [0.996-1.018]
    
                              PM25 total carbon:
    
                              RD: 1.001 [0.993-1.008]
    
                              PM25OC:
    
                              RD: 1.003 [0.995-1.011]
    
                              PM25 EC:
    
                              RD: 0.996 [0.989-1.004]
    
                              PM2 5 water-soluble metals:
    
                              RD: 1.005 [0.995-1.015]
    December 2009
                            E-281
    

    -------
    Reference Design & Methods
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Wong et al. (2006, 0932661 General Practitioner Visits
    Period of Study: 2000-2002 Outcome (ICPC-2): Respiratory
    diseases/symptoms: upper respiratory
    Location: Hong Kong (8 districts) tract infections (URTI), lower respiratory
    infections, influenza, asthma, COPD,
    allergic rhinitis, cough, and other
    respiratory diseases
    Age Groups: All ages
    Study Design: Time series
    N: 269,579 visits
    Concentrations1
    PM25S04:r = 0.34
    PM25EC:r = 0.91
    PM25OC:r = 0.98
    PM2 5 water-sol metals:
    r = 0.52
    OHC:r = 0.38
    Between PM25 water-soluble metals
    and: PM10: r = 073
    03:r = 0.43
    N02:r = 0.32
    CO: r = 0.35
    S02:r = 0.06
    PM10.25:r = 0.50
    PM25:r = 0.69
    PM25S04:r = 0.65
    PM25EC:r = 0.52
    PM25OC:r = 0.49
    PM25TC:r = 0.52
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (min-max):
    35.7(9-120)
    SD=16.7
    Monitoring Stations: 1 per district
    Copollutant (correlation):
    PM10:r = 0.94
    Effect Estimates (95% Cl)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    PM Increment: 10 pg/m3
    RR Estimate [Cl]:
    Overall URTI
    1.021 [1.010,1.032]
    Notes: RRs are also reported for each
    individual general practitioner yielding
    similar results
    
    
                                        Statistical Analyses: GAM, Poisson
                                        regression
                                        Covariates: Season, day of the week,
                                        climate
                                        Season: NR
                                        Dose-response Investigated? No
                                        Statistical Package: S-Plus
                                        Lags Considered: 0-3 days
    Reference: Yang Q et al. (2004,
    0874881
    Period of Study: Jun 1995-Mar 1999
    Location: Vancouver area, British
    Columbia
    Hospital Admissions
    Outcome (ICD-9): Respiratory
    diseases (460-51 9), pneumonia only
    (480-486), asthma only (493)
    Age Groups: 0-3 yr
    Study Design: Case control,
    Pollutant: PM25
    Averaging Time: 24 h
    Mean (min-max):
    7.7 (2.0-32.0)
    SD = 3.7
    PM Increment: 4.0 pg/m3 (IQR)
    OR Estimate [Cl]:
    Values NR
    Notes: Author states that no significant
    association was found between PM25
    and respiratory disease hospitalizations.
                                        bidirectional case-crossover (BCC), and
                                        time series (TS)
                                        N: 1610 cases
                                        Statistical Analyses: Chi-square test,
                                        Logistic regression, GAM (time-series),
                                        GLM with parametric natural cubic
                                        splines
                                        Covariates: Gender, socioeconomic
                                        status, weekday, season, study yr,
                                        influenza epidemic month
                                        Season: Spring, summer, fall, winter
                                        Dose-response Investigated? No
                                        Statistical Package: SAS (Case
                                        control and BCC), S-Plus (TS)
                                        Lags Considered: 0-7 days
        Monitoring Stations: NR (data
        obtained from Greater Vancouver
        Regional District Air Quality Dept)
        Copollutant (correlation):
        PM,0:r = 0.83
        PM10.25:r = 0.39
        CO: r = 0.24
        03:r = -0.03
        N02:r = 0.37
        S02:r = 0.43
    December 2009
    E-282
    

    -------
                Reference
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Zanobetti and Schwartz
    (2006, 0901951
    Period of Study: 1995-1999
    Location: Boston, MA
    Hospital Admission/ED:
    Outcome: Pneumonia (480-487)
    Age Groups: >65 y
    Study Design: Case-crossover, time
    stratified
    N: 24,857 for Pneumonia
    Statistical Analyses: Condition logistic
    regression
    Covariates: Season, long term trend,
    day of-the-wk, mean temperature,
    relative humidity, barometric pressure,
    extinction coefficient
    Pollutant: PM non-traffic
    Averaging Time: 24 h
    Percentiles (pneumonia cohort):
    5th: -7.3
    25th: -3.28 pg/m3
    SOth(Median): -0.88
    75th: 1.92
    95th: 12.11
    PM Component: BC
    Monitoring Stations: 4-5 monitors
    PM Increment: PM non-traffic lag 0:
    13.44|jg/m3
    PM non-traffic lag 0-1 avg: 10.28 pg/m3
    % change in Pneumonia:
    PM non-traffic-0.57 [-7.51, 6.36]
    lagO
    PM non-traffic-0.94 [-7.20, 5.32]
    mean lag 1
    
    
    
    
    
    
    
    Reference: Zhong et al. (2006,
    0932641
    
    Period of Study: Apr-Oct 2002
    Location: Cincinnati, Ohio
    
    
    
    
    
    
    
    
    Season: All yr
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    Lags Considered: 0-1
    Notes: Also looked at Ml cohort
    Hospital Admissions
    
    Outcome (ICD-9): Asthma (493-
    493.91)
    Age Groups: 1-18 yr
    Study Design: Time series
    
    N: 1254 admissions
    Statistical Analyses: Poisson multiple
    regression, GAM
    
    Covariates: Season, temperature,
    humidity, 03, day of the week
    i/Qpuiiurani iCQiieiauunj.
    PM non-traffic:
    PM25r = 0.74
    CO r = -0.01
    N02r = 0.14
    03r = -0.47
    BC r = -0.01
    
    Pollutant: PM25
    
    Averaging Time: 24 h
    Mean (SD):
    Apr: 12.4 (3.8)
    May: 13.6 (5.8)
    Jun: 21.6 (9.9)
    Jul: 25.8 (11.9)
    Aug: 20.3 (8.7)
    Sep: 19.5 (11.1)
    Oct: 12.8 (6.4)
    
    Monitoring Stations: NR (data
    obtained from the National Virtual Data
    System)
    
    
    
    
    
    
    
    PM Increment: NR
    
    RR Estimate [Cl]:
    NR
    Notes: This study focused primarily on
    aeroallergens and asthma visits
    
    
    
    
    
    
    
                                       Season: NR
                                       Dose-response Investigated? Yes
                                       Statistical Package: NR
                                       Lags Considered: 1-5 days
                                        Copollutant (correlation): NR
                                        Notes: Author states all pairwise
                                        correlations were insignificant
    Reference: Zanobetti and Schwartz
    (2006, 0901951
    Period of Study: 1995-1999
    Location: Boston, MA
    Outcome: Pneumonia (480-487)
    Age Groups: >65 y
    Study Design: Case-crossover, time
    stratified
    N: 24,857 for Pneumonia
    Statistical Analyses: Condition logistic
    regression
    Covariates: Season, long term trend,
    day of-the-wk, mean temperature,
    relative humidity, barometric pressure,
    extinction coefficient
    Season: All yr
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: 0-1
    Notes: Also looked at Ml cohort
    Pollutant: PM25
    Averaging Time: 24 h
    Percentiles (pneumonia cohort):
    25th: 7.23 pg/m3
    50th(Median):11.10
    75th: 16.14
    PM Component: Black Carbon (BC),
    PM non-traffic
    Monitoring Stations: 4-5 monitors
    Copollutant (correlation):
    PM25:
    CO r = 0.52
    N02r = 0.55
    03r = 0.20
    BC r = 0.66
    PM non-traffic r = 0.74
    PM Increment: PM25 lag 0:
    17.17 pg/m3
    PM25lagO-1 avg: 16.32 pg/m3
    % change in Pneumonia:
    6.48[1.13,11.43]
    lagO
    5.56[-0.45, 11.27]
    mean lag 1
    'All units expressed in ug/m3 unless otherwise specified.
    December 2009
                                    E-283
    

    -------
    Table E-15.    Short-term exposure-respiratory-ED/HA-Other Size Fractions.
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Andersen et al. (2007,
    0932011
    Period of Study: 2001-2004
    
    Location: Copenhagen, Denmark
    Outcome (ICD10):
    Respiratory disease (J41-46)
    Asthma (J45, 46)
    
    Age Groups: 5-18 and >65
    
    Study Design: Time-series
    
    N: 1327 days
    -1.5 million people at-risk
    
    Statistical Analyses: Poisson
    regression, GAM.
    
    Covariates: Influenza epidemics,
    pollen, temperature, dew point, day-of-
    week, holiday, season.
    
    Season: All
    
    Dose-response Investigated? No
    
    Statistical Package: R with gam and
    mgcv packages.
    
    Lags Considered: 0-5
    Pollutant: Number concentration (NC)
    of ultrafme & accumulation mode
    particles
    
    Averaging Time: 24 h
    Mean particles/cm3 (SD):
    NCtot (total): 8116 (3502)
    25th: 4959
    50th: 6243
    75th: 8218
    99th: 16189
    IQR: 3259
    NC100(<100nm): 6847 (2864)
    25th: 5738
    50th (Median): 7358
    75th: 9645
    99th: 19895
    IQR: 3907
    Mean particles/cm3 for 4 size modes
    (median diameter (nm) noted):
    NCa12: 493(315)
    NCa23: 2253 (1364)
    NCa57: 5104 (2687)
    NCa212:6847(2864)
    Monitoring Stations: 3 (Background,
    rural Background, urban Curbside,
    urban)
    
    Notes:  NC exposure data available for
    n =  578 days. Information on
    distribution of 4 size modes provided in
    the  paper.
    Copollutant (correlation):
    NCtot and PM,0:r = 0.39
    NCtot and PM25:r = 0.40
    NCtot and N02:r = 0.68
    PM10andPM25: r = 0.8
    "Low or no" correlations between 4 size
    modes
    NCa212andPM25:r = 0.8
    NCa212 and PM,0:r = 0.63
    NCa57 and N02:r = 0.57
    Notes: selected correlations reported in
    text, all  correlations in annex to the
    manuscript
    PM Increment: Based on the IQR,
    specific to metric (see below).
    
    RR Estimate:
    Single pollutant results, Asthma,
    (5-18 yr), lag 0-5:
    PM25:1.15 [1,1.32], IQr = 5
    NCtot: 1.07 [0.98,1.17], IQr = 3907
    NC100:1.06 [0.97,  1.16], IQr = 3259
    NCa12:1.08 [0.99,1.18], IQr = 342
    NCa212:1.08[1,1.17], IQr = 495
    NCa23:1.09 [0.98,1.21 , IQr=1786
    NCa57:1.02 [0.94,1.12, IQr = 3026
    2-pollutant results:
    NCa212w/PM10:1.1 [0.96,  1.13],
    IQr = 495
    NCtot w/PM,0:1.03 [0.92, 1.15]
    NCtotw/PM25:1.04 [0.85, 1.28]
    All RD, (>65 yr), lag 0-4, single pollutant
    results:
    PM25:1 [0.95, 1.05]
    NCtot: 1.04 [1,1.07] IQr = 3907
    NC100:1.03 [0.99,  1.07], IQr = 3259
    NC12:1.01 [0.98, 1.05], IQr = 342
    NC212:1.04 [1.01,  1.08], IQr = 495
    NCa23: 0.99 [0.94,  1.03], IQr= 1786
    NCa57:1.04[1, 1.08], IQr = 3026
    2-pollutant results:
    NCa212w/PM10:1.01 [0.96, 1.07],
    IQr = 495
    NCtot w/PM25: 0.97 [0.89, 1.05]
    NCtot w/PM10:1 [0.96, 1.05]
    Notes: Multipollutant model  results also
    included for models with 4 size modes.
    Reference: Agarwal et al. (2006,
    0990861
    Period of Study: 2000-2003
    
    Location: Safdarjung area of Delhi
    Outcome (ICD-NR): COPD, asthma,
    emphysema
    
    Age Groups: NR
    
    Study Design: Time series
    
    N:NR
    
    Statistical Analyses: Kruskal-VVallis
    one-way analysis,  Chi-square,
    Multivariate linear  regression
    
    Covariates: Temp (min & max), relative
    humidity at 0830 and 1730 h, wind
    speed
    
    Season: I (Jan-Mar), II (Apr-Jun), III
    (Jul-Sep), IV (dot-Dec)
    
    Dose-response Investigated? Yes
    
    Statistical Package: SPSS
    
    Lags Considered: NR
    Pollutant: SPM (Suspended PM)
    
    Averaging Time: 8 h
    
    Mean pg/m3 (SD):
    
    Qtr I: 297.5 (34.6)
    
    Qtr II: 398.0 (85.6)
    
    Qtr III: 220.0 (78.0)
    
    Qtr IV: 399.0 (54.6)
    
    Monitoring Stations: 2
    
    Copollutant (correlation):
    RSPM:r = 0.771
    
    Other variables:
    
    RH0830:r =-0.482
    
    RH1730:r =-0.531
    
    COPD: r = 0.474
    PM Increment: NR
    
    RR Estimate [Cl]: NR
    
    Notes: This study analyzed seasonal
    variation of pollutants and health
    outcomes and correlations among the
    variables
    December 2009
                                   E-284
    

    -------
    Study
    Reference: Agarwal et al. (2006,
    0990861
    Period of Study: 2000-2003
    Location: Safdarjung area of Delhi
    
    
    
    
    
    
    
    
    
    
    
    Reference: Arbex et al. (2007, 0916371
    Period of Study: Mar 2003-Jul 2004
    Location: Araraquara, Sao Paulo State,
    Brazil
    
    
    
    
    Design & Methods
    Outcome (ICD-NR): COPD, asthma,
    emphysema
    Age Groups: NR
    Study Design: Time series
    N:NR
    Statistical Analyses: Kruskal-Wallis
    one-way analysis, Chi-square,
    Multivariate linear regression
    Covariates: Temp (min & max), relative
    humidity at 0830 and 1730 h, wind
    speed
    Season: I (Jan-Mar), II (Apr-Jun), III
    (Jul-Sep), IV (dot-Dec)
    Dose-response Investigated? Yes
    Statistical Package: SPSS
    Lags Considered: NR
    Hospital Admission
    Outcome (ICD10): Asthma (J15, J45)
    Age Groups: All
    Study Design: Time-series
    
    N: 493 days, 1 hospital, 640 admissions
    Statistical Analyses: Generalized
    linear Poisson regression model with
    natural cubic spline, Mann-Whitney U
    Test
    Covariates: Temperature and humidity
    Season: All
    Concentrations1
    Pollutant: RSPM (Respirable
    Suspended PM <10|jm)
    Averaging Time: 8 h
    Mean pg/m3 (SD):
    Qtr 1: 119.0 (19.8)
    Qtr II: 132.0 (28.4)
    
    Qtr III: 75.0(23.4)
    Qtr IV: 168. 0(40. 6)
    Monitoring Stations: 2
    Copollutant (correlation): SPM:
    r - n 771
    I ~ U. 1 1 \
    Other variables:
    Temp (min): r = -0.420
    COPD: r = 0.353
    Pollutant: TSP
    Averaging Time: 24 h
    Mean (SD): 46.8 pg/m3 (24.4)
    Range (Min, Max):
    
    6.7-1 37.8 pg/m3
    Monitoring Stations: 1
    Notes: TSP used as a proxy for fine &
    ultrafine particles since it is composed
    of 85-95% PM2.5.
    Copollutant (correlation): NR
    Effect Estimates (95% Cl)
    PM Increment: NR
    RR Estimate [Cl]: NR
    Notes: This study analyzed seasonal
    variation of pollutants and health
    outcomes and correlations among the
    variables
    
    
    
    
    
    
    
    
    
    
    PM Increment: 10 pg/m3
    % Increase
    6.96 [1.4-12.86] 2-day ma
    9.090 3. 12-1 5.40] 3 day ma
    10.28 4.05-16.90] 4-day ma
    11.63 5. 46-19.318] 5 day ma
    12.61 5.68-20.00] 6-day ma
    12.56 5. 47-20. 13] 7-day ma
    % Increase by TSP quintile:
    9.25-28. 45 pg/m3:: 1.00
    28.46-48.85 pg/m3: : 1.55 045-5.77]
    48.86-69.06 pg/m3: : 2.46 1.08-5.60]
    69.07-88.44 pg/m3: : 2.77 1.32-5.84]
    88. 45-108.9 pg/m3:: 2.94 1.48-5.85]
                                        Dose-response Investigated? Yes,
                                        quintile analysis
    
                                        Statistical Package: SPSS V11 &
                                        Splus 4.5
    
                                        Lags Considered: 0-9
                                           Notes: No TSP threshold for asthma
                                           admissions noted. Analysis of lag
                                           structure indicated that the acute effect
                                           of TSP on admissions started 1 day
                                           after TSP concentration increase and
                                           remained unchanged for next 4 days.
    
                                           Notes: To evaluate the association
                                           between TSP generated from burning
                                           sugar cane and asthma hospital
                                           admissions.
    Reference: Bartzokas et al. (2004,
    0932521
    Period of Study: Jun 1992-May 2000
    Location: Athens, Greece
    
    
    
    
    
    
    
    
    
    
    Outcome: Respiratory and
    cardiovascular diseases (combined)
    Age Groups: NR
    Study Design: Time series
    N: 1554 patients
    Statistical Analyses: Simple linear
    regression and linear stepwise
    regression, Pearson correlation
    Covariates: Temperature, atmospheric
    pressure, relative humidity, wind speed
    Season: Warm (May-Sep) and cold
    (Nov-Mar)
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: NR
    Pollutant: PM4.5 (black smoke)
    Averaging Time: 10-day ma
    Mean|jg/m3(SD):NR
    Monitoring Stations: 1
    Copollutant (correlation): N
    
    
    
    
    
    
    
    
    
    PM Increment: NR
    Correlation with Number of
    Admissions:
    Entire yr
    Original: r = 0.18
    Smoothed: r = 0.31
    
    Warm period
    Original: r = 0.19
    Smoothed: r = 0.30
    Cold period
    Original: r = 0.18
    Smoothed: r = 0.34
    *AII above values are statistically
    significant
    December 2009
    E-285
    

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                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Erbas et al. (2005, 0738491
    Period of Study: Jul 1989-Dec 1992
    Location: Melbourne, Australia
    Outcome (ICD):
    COPD (490-492, 494, 496)
    Asthma (493)
    Age Groups: NR
    Study Design: Time series
    N:NR
    Statistical Analyses: GLM, GAM,
    Parameter Driven Poisson Regression,
    Transitional Regression, Seasonal-
    Trend decomposition based on Loess
    smoothing for seasonal adjustment
    Covariates: Secular trends,
    seasonality, relative humidity, dry bulb
    temp, dew point temp
    Season: NR
    Dose-response Investigated? Yes
    Statistical Package: S-Plus, SAS
    Lags Considered: 0-5 days
    Pollutant: PM 0.1-1 (API)
    Averaging Time: 24 h
    Mean (min-max): NR
    Monitoring Stations: 9
    Copollutant (correlation): NR
    PM Increment: Increase from the 10th-
    90th percentile (value NR)
    RR Estimate [Cl]:
    COPD
    GAM:
    0.95 [0.91,1.00]
    GLM, PDM,TRM:NR
    Asthma
    NR
    Notes: This study was used to
    demonstrate that conclusions are highly
    dependent on the type of model used
    Reference: Halonen et al. (2008,
    1895071
    Period of Study: 1998-2004
    Location: Helsinki, Finland
    Outcome: Respiratory Hospitalizations
    & Mortality (ICD 10: JOO-99)
    Age Groups: 65+ yr
    Study Design: Time series
    N:NR
    Statistical Analyses: Poisson, GAM
    Covariates: Temperature, humidity,
    influenza epidemics, high pollen
    episodes, holidays
    Dose-response Investigated? No
    Statistical Package: R
    Lags Considered: Lags 0-3 & 5-day
    (0-4) mean
    Pollutant: PM25
    Averaging Time: Daily
    Mean (SD): NR
    Min:1.1
    26th percentile: 5.5
    60th percentile: 9.5
    76th percentile: 11.7
    Max: 69.5
    Monitoring Stations: NR
    Copollutant: PM<0.03, PMO.03-0.1,
    PM<0.1,
    PM<0.10.29, PM10.25, CO, N02
    Co-pollutant Correlation
    PM<0.03:0.14
    PMO.03-0.1: 0.48
    PM<0.1:0.35
    PM<0.10.29:0.88
    PM10.2.5: 0.25
    PM Increment: Interquartile
    Percent Change (Lower Cl, Upper
    Cl):
    All Respiratory Mortality
    Lag 0: 2.67 (-0.39, 5.82 J
    Lag 1:1.59 (-1.43, 4.70
    Lag 2: 0.03 (-2.99, 3.16)
    Lag 3:-0.11  (-3.13,3.01)
    5-day mean: 1.39 (-2.83, 5.81)
    Pneumonia HA
    Lag 0: 0.93 (-0.85, 2.75)
    Lag 1:2.41 (0.64, 4.21)
    Lag 2:1.48 (-0.27, 3.26)
    Lag 3:1.91 (0.14, 3.70)
    5-day mean: 3.10 (0.60, 5.65)
    Asthma + COPD HA
    Lag 0: 2.48 (0.60, 4.39)
    Lag 1:2.62 (0.78, 4.49)
    Lag2:1.22(-0.62, 3.10)
    Lag 3: 0.59 (-1.28, 2.49)
    5-day mean: 2.49 (-0.08, 5.12)
    Other HA
    Lag 0: 0.05 (-2.38, 2.54)
    Lag 1:0.2 (-2.17, 2.62)
    Lag 2: 2.03 (-0.29, 4.41)
    Lag 3:1.72 (-0.63, 4.12)
    5-day mean: 1.88 (-1.50, 5.36)
    *p<0.05, Jp<0.10
    December 2009
                                    E-286
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Llorca et al. (2005, 0878251
    
    Period of Study: Jan 1992-Dec 1995
    
    Location: Torrelavega, Spain
    Outcome (ICD-9): Respiratory (460-
    519) and cardiac (390-459) admissions
    (analyzed combined and individually)
    
    Age Groups: NR
    
    Study Design: Time series
    
    N: 18,137 admissions
    
    Statistical Analyses: Stepwise multiple
    linear regression,  Poisson regression,
    Spearman correlation
    
    Covariates: Influenza, day of week,
    wind speed, northeast and southwest
    winds, minimum and maximum
    temperature
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: STATA
    Interceded,  Release 6
    
    Lags Considered: NR
    Pollutant: TSP (total suspended
    particles)
    
    Averaging Time: 24 h
    
    Mean pg/m3 (SD):
    
    48.8 (23.7)
    
    Monitoring Stations: 3
    Copollutant (correlation):
    S02:r =-0.400
    SH2:r =-0.392
    NO: r = -0.109
    N02:r =-0.120
    
    Other variables:
    Rain: r = -0.339
    Max temp: r = 0.071
    Min temp: r = -0.003
    Avg temp: r = 0.035
    Wind speed: r = -0.357
    PM Increment: NR
    
    Rate Ratio Estimate [Cl]:
    
    Cardiorespiratory Admissions
    
    Single-pollutant model: 0.92 [0.86,0.98]
    
    Five-pollutant model: 1.05 [0.97,1.14]
    
    Respiratory Admissions
    
    Single-pollutant model: 0.98 [0.89,1.08]
    
    Five-pollutant model: 0.91 [0.80,1.02]
    Reference: Michaud et al. (2004,
    1885301
    
    Period of Study: Jan 1997-May 2001
    
    Location: Hilo, Hawaii
    ED visits
    
    Outcome: Asthma/COPD (490-496)
    Respiratory Irritation (506-508)
    
    Age Groups: All
    
    Study Design: Time-series
    
    N:1,561 ER visits
    
    Statistical Analyses: Multiple linear
    regression
    
    Covariates: Hourly temperature,
    minimum daily temperature,  minimum
    daily temperature, humidity, yr, month,
    day of the week
    
    Season: all
    
    Dose-response Investigated? No
    
    Statistical Package:
    
    STATA 6.0
    
    SAS
    
    Lags Considered: Previous night,
    1,2,3
    Pollutant: PM1
    
    Averaging Time: 24-h avg
    
    Mean (SD): 1.91 (2.95) pg/m3
    
    Range (Min, Max):
    
    0.0, 56.6 pg/m3
    
    Monitoring Stations: 2
    
    Notes: Copollutant (correlation): NR
    PM Increment: 10 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Asthma, COPD (499-496): Adjusted for
    day, month & yr:
    1.11(0.92, 1.34), 00: 00-6: 00AM
    1.14(1.03,1.26), lag 1
    1.06(0.83, 0.94), lag 2
    0.91 (0.06, 1.05), Iag3
    
    Asthma (493, 495):  Adjusted for day,
    month & yr:
    1.03(0.90, 1.42), 00: 00-6: 00AM
    1.02(0.94,1.21), lag 1
    1.02(0.99, 1.23), lag 2
    0.97(0.69, 1.15), Iag3
    
    Bronchitis (490, 491): Adjusted for day,
    month & yr:
    1.02(0.82, 1.41), 00: 00-6: 00AM
    1.07(1.18,1.49), lag 1
    0.97(0.60, 1.34), lag 2
    0.93(0.43, 1.18), Iag3
    Notes: Crude and estimates adjusted
    for month and yr only also presented.
    
    Notes: Volcanic fog = vog
    December 2009
                                    E-287
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Migliaretti et al. (2005,
    0886891
    Period of Study: 1997-1999
    Location: Turin, Italy
    Cases: Asthma (493)
    Controls: Admissions for non-
    respiratory or cardiac conditions (460-
    487, 490-493, 494-496, 500-519, 390-
    405, 410-429)
    Age Groups:  0-14,15-64, >64
    Study Design: Case-control
    N: Cases: 1,401
    Controls: 201,071
    Statistical Analyses: Logistic
    regression
    Covariates: Gender, age, daily mean
    temperature, season, day of week,
    holidays,  education level
    Season:  All
    Dose-response Investigated? No
    Lag :0-to 2-day avg
    Pollutant: TSP
    Averaging Time: Means of daily total
    levels at stations
    Mean (SD): 105.3 pg/m3, (44.2)
    Percentiles: 26th: NR
    60th(Median): 96.0 pg/m3
    75th NR
    Monitoring Stations:
    10
    Notes: Copollutant (correlation):
    All seasons: N03"TSP = 0.80
    Winter: NOfTSP  = 0.77
    Summer: N03~TSP = 0.69
    PM Increment: 10 pg/m increase
    % Increase, lag 0-2-day avg
    1 pollutant model:
    <15:1.90[0.40, 3.40]
    15-64: 2.30 [-0.01, 5.20]
    >64: 2.30 [1.10, 3.60]
    Total: 2.30[1.10, 3.60]
    % Increase, lag 0-2-day avg
    2 pollutant model:
    <15:-0.12 [-0.03, 2.50]
    15-64: 0.90 [-0.04, 5.61]
    >64:1.2 [-0.01, 4.32]
    Total: 0.91 [-0.02,3.11]
    Reference: Migliaretti et al. (2004,
    0874251
    Period of Study: 1997-1999
    Location: Turin, Italy
    Outcome:
    Cases: Asthma (493)
    Controls: Non-respiratory or cardiac
    admissions (460-487, 490-493, 494-
    496, 500-519, 390-405, 410-429)
    Age Groups: 0-15
    Study Design: Case-control
    N: Cases: 1,060
    Controls: 25,523
    Statistical Analyses: Logistic
    regression pg/m increase
    Covariates: Gender, age, daily mean
    temperature, season, day of week,
    holidays,  solar radiation
    Season:  All
    Lags Considered: 1- to 3-day avg
    Pollutant: Total suspended particulate   PM Increment: 10 pg/m
    Averaging Time: Mean of admission
    day and 3 preceding days
    Mean (SD): 114.5 pg/m3, (42.8)
    Percentiles:
    25th: NR
    SOth(Median): 109.9 pg/m3
    75th: NR
    Monitoring Stations: 10
    Notes: Copollutant (correlation):
    TSP-NO: 0.76
    % Increase, lag 1-3-day avg
    <4yr: 1.8% [0.00, 3.05]
    4-15 yr: 3.0% [0.01, 5.08]
    all: 1.8% [0.03, 3.02]
    adjusted for all covariates
    Notes: Multipollutant models also used
    Reference: Neuberger et al. (2004,
    0932491
    Period of Study: 1999-2000 (1-yr
    period)
    Location: Vienna and Lower Austria
    Outcome (ICD-9): Bronchitis,
    emphysema, asthma, bronchiectasis,
    extrinsic allergic alveolitis, and chronic
    airway obstruction (490-496)
    Age Groups: 3.0-5.9 yr
    7-1 Oyr
    65+yr
    Study Design: Time series
    N: 366 days (admissions NR)
    Statistical Analyses: GAM
    Covariates: S02, NO, N02, 03,
    temperature, humidity, and day of the
    week
    Season: NR
    Dose-response Investigated? Yes
    Statistical Package: S-Plus 2000
    Lags Considered: 0-14 days
    Pollutant: PMi
    Averaging Time: 24 h
    Mean|jg/m3(SD):NR
    Monitoring Stations: NR
    Copollutant (correlation): NR
    PM Increment: NR
    Effect parameters (Vienna children):
    Respiratory Health
    Male sex = 0.098
    Allergy = 0.238
    Asthma in family = 0.190
    Traffic = 0.112
    Log Asthma Score
    Allergy = 0.210
    Asthma in family = 0.112
    Rain = 0.257
    "only significant coefficients are
    presented
    Association with tidal lung function:
    P =-1.059 (p-value = 0.060)
    Notes: No significant associations
    between PM and respiratory mortality
    were found for either sex. Data is also
    provided for children in the rural area
    where age, allergy, asthma in family,
    passive smoking, and  PM fraction had
    significant coefficients.
    December 2009
                                    E-288
    

    -------
    Study
    Reference: Peel et al. (2005, 0563051
    Period of Study: Jan 1993-Aug 2000
    Location: Atlanta, Georgia
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Simpson et al. (2005,
    0874381
    Period of Study: 1996-1999
    Location: Brisbane, Sydney,
    Melbourne, and Perth, Australia
    
    
    Design & Methods
    Hospital Admission/ED:
    ED visits
    Outcome: Asthma 493, 786.09
    COPD 491, 492, 496
    URI 460-466, 477
    Pneumonia 480-486
    Age Groups: All ages. Secondary
    analyses conducted by age group:
    Infants 0-1 yr
    Pediatric asthma 2-1 Syr
    Adults >18yr
    Study Design: Case-control
    All respiratory disease vs. finger
    wounds
    N: 31 hospitals
    ED visits NR
    Statistical Analyses: Poisson
    generalized linear models
    General linear models
    
    Covariates: Avg temperature and dew
    point, pollen counts
    Season: All
    Dose-response Investigated? Yes
    Statistical Package: SAS 8.3
    S-Plus2000
    Lags Considered: 0-7 days and
    14-day distributed lag
    Outcome: All Respiratory (460-519)
    Asthma (493)
    COPD (490-492)
    Pneumonia, acute bronchitis (466,
    480-486)
    Age Groups: All ages, split into f15-64
    and >64 yr
    Study Design: Time-series
    N: NR -64,000 admissions
    Concentrations1
    Pollutant: UF(1 0-1 OOnm)
    Averaging Time: 24-h avg
    Mean (SD): 3800 (40700)
    
    Percentiles:
    10th: 11500
    90th: 74600
    PM Component: Oxygenated
    hydrocarbons (OH), sulfate, acidity, EC
    (EC), OC (OC), water-soluble transition
    metals
    Monitoring Stations: "Several"
    Copollutant (correlation):
    PM,0:r = -0.13
    03:r = -0.13
    N02:r = 0.26
    
    CO: r = 0.10
    
    S02: r = 0.24
    PM25:r = -0.16
    PM10.25:r = 0.13
    
    
    
    
    Pollutant: BSP (indicator of particles
    <2 pm in diameter)
    Averaging Time: 24-h avg
    Mean (SD): Means only
    Brisbane 0.3 10 -4 m-1
    Sydney 0.3 10 -4 m-1
    Effect Estimates (95% Cl)
    Increment:
    30,000 #/cm3
    All Respiratory Disease
    
    0.984 [0.968-1. 000]
    URI
    0.986 [0.966, 1.006]
    Asthma
    0.999 [0.977, 1.021]
    Pneumonia
    0.997 [0.953, 1.002]
    COPD
    0.982 [0.942, 1.022]
    
    
    
    
    
    
    
    
    
    
    
    
    PM Increment: "per unit increase"
    RR Estimate [Lower Cl, Upper Cl]
    Ian-
    lag.
    Single pollutant model
    Respiratory >64 yr
    1.0401 1.0045, 1.0770] Iag1
    1.0520 1.0164, 1.0889] Iag2;
    1.0451 1.0093, 1.0821] Iag3
    1.0552 1.0082, 1.1 045] lag 0-1 avg
                                        Statistical Analyses: GAM w/ LOESS
                                        smoothers
    
                                        GLM w/ natural and penalized spline
                                        smoothers
    
                                        Covariates: Temperature, relative
                                        humidity, rain, day of the week, public
                                        and school  holidays, influenza
                                        epidemics,  and controlled burn events
    
                                        Season: All
    
                                        Dose-response Investigated? Yes
    
                                        Statistical Package: S-Plus
    
                                        R Lags Considered: 1-3 days, 0- to
                                        1-day avg
        Melbourne 0.3 10-4 m-1
    
        Perth 0.3 10-4 m-1
    
        Range (Min, Max):
    
        Brisbane0.0, 2.5 10-4m-1
    
        Sydney 0.0,  1.6 10-4 m-1
    
        Melbourne0.0, 2.2 10-4m-1
    
        Perth 0.1,1.8 10-4 m-1
    
        PM Component: Monitoring Stations:
        "network of sites across each city"
    
        Copollutant (correlation): NR
    Asthma 15-64 yr
    1.0641 [1.0006, 1.1315] Iag2
    1.0893 [1.0240, 1.1587] Iag3
    Asthma + COPD >64 yr
    1.0713 [1.0179, 1.1276] lagS
    1.0552 [1.0082,1.1045] lag 0-1 avg
    Pneumonia & Acute Bronchitis >64 yr
    1.0587 [1.0013, 1.1193] Iag1
    1.0636 [1.0056, 1.1249] lag 2
    1.0769 [1.0046,1.1544] lag 0-1 avg
    Multipollutant model
    Respiratory admissions >64 yr
    No other pollutants:
    1.0552 [1.0082,1.1045] lag 0-1 avg
    Max 1 h N02
    1.0028 [0.9513,1.0572] lag 0-1 avg
    Max 1 h 03
    1.0534 [1.0058-1.1033] lag 0-1 avg
    December 2009
    E-289
    

    -------
    Study
    Reference: Sinclair and Tolsma (2004,
    0886961
    
    Period of Study: 25 mo
    Location: Atlanta, Georgia
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outpatient Visits
    
    Outcome: Asthma (493)
    URI (460, 461, 462, 463, 464, 465, 466,
    477)
    LRI (466. 1,480, 481,482, 483, 484,
    485, 486).
    Age Groups: < = 18 yr; 18+ yr
    (asthma); All ages (URI//LRI)
    Study Design: Times series
    N:25mo
    260,000-275,000 health plan members
    (Aug1998-Aug2000)
    Statistical Analyses: Poisson GLM
    Covariates: Season, day of week,
    federal holidays, study months
    
    Concentrations1
    Pollutant: PM2.5.io (|jg/m3)
    
    Averaging Time: 24-h avg
    Mean (SD): PM coarse mass
    (2.5-10 |jm)-9.67 pg/m3 (4.74)
    Monitoring Stations: 1
    Copollutant (correlation): NR
    
    
    
    
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 4.74 (1 SD)
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Child Asthma:
    Coarse PM = 1.053(3)
    3-5 day lag
    URI:
    Course PM = 1.021 (S)
    
    3-5 day lag
    LRI:
    Coarse PM = 1.07(3)
    
    3-5 day lag
                                       Season: NR
                                       Dose-response Investigated?: No
                                       Statistical Package: SAS
                                       Lags Considered: Three 3-day ma
                                       (0-2, 2-5, 6-8)
                                                                          Notes: Numerical findings for significant
                                                                          results only presented in manuscript.
                                                                          Results for all lags presented
                                                                          graphically for each outcome (asthma,
                                                                          URI, and LRI).
    Reference: Sinclair and Tolsma (2004,
    0886961
    Period of Study: 25 mo
    Location: Atlanta, Georgia
    Outpatient Visits
    Outcome: Asthma (493)
    URI (460, 461, 462, 463, 464, 465, 466,
    477)
    LRI (466.1,480, 481,482, 483, 484,
    485, 486).
    Age Groups: < = 18 yr, 18+ yr (asthma)
    All ages (URI//LRI)
    Study Design: Times series
    N:25mo
    260,000-275,000 health plan members
    (Aug1998-Aug2000)
    Statistical Analyses: Poisson GLM
    Covariates: Season, day of week,
    federal holidays, study months
    Season: NR
    Dose-response Investigated?: No
    Statistical Package: SAS
    Lags Considered: Three 3-day ma
    (0-2, 2-5, 6-8)
    Pollutant: UF(PM,o-100nm)
    Averaging Time: 24 h avg
    Mean (SD): PM10-100 nm area
    (|jm2/cm3)- 249.33 (244.09)
    Monitoring Stations: 1
    Copollutant (correlation): NR
    PM Increment: NR
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Adult Asthma:
    UltrafinePM area = 1.223(3)
    3-5 days lag
    URI:
    UltrafinePM: = 1.041  (S)
    0-2 days lag
    LRI:
    UltrafinePM area = 1.099(3)
    6-8 days lag
    Notes: Numerical findings for significant
    results only presented in manuscript.
    Results for all lags presented
    graphically for each outcome (asthma,
    URI, and LRI).
    December 2009
                                   E-290
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Slaughter et al. (2005,
    0738541
    Period of Study: Jan 1995-Jun 2001
    
    Location: Spokane, WA
    Hospital Admissions and ED visits
    Outcome: All respiratory (460-519)
    Asthma (493)
    COPD (491,492, 494,496)
    Pneumonia (480-487)
    Acute URI not including colds and
    sinusitis (464, 466, 490)
    Age Groups: All, 15+ yr for COPD
    
    Study Design:  Time series
    
    N: 2373 visit records
    
    Statistical Analyses: Poisson
    regression, GLM with natural splines.
    For comparison also used GAM with
    smoothing splines and default
    convergence criteria.
    
    Covariates: Season, temperature,
    relative humidity, day of week
    
    Season: All
    
    Dose-response Investigated?: No
    
    Statistical Package: SAS, SPLUS
    
    Lags Considered: 1 -3 days
    Pollutant: PMi
    
    Averaging Time: 24-h avg
    
    Range (90% of concentrations):
    3.3-17.6 pg/m3
    
    Monitoring Stations: 1
    
    Copollutant (correlation):
    PM,
    
    PM25r = 0.95
    
    PM10r = 0.50
    
    PMi0.25r = 0.19
    
    CO r = 0.63
    PM Increment: 10 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    
    lag:
    
    ED visits:
    
    PM,
    
    All Respiratory
    
    Lag1:1.01 [0.98,1.04]
    
    Lag 2:1.02 [0.99,1.06]
    
    Lag 3:1.02 [0.99,1.06]
    
    Acute Asthma
    
    Lag 1:1.03 [0.97,1.09]
    
    Lag 2: 0.99 [0.93, 1.05]
    
    Lag 3:1.02 [0.96,1.08]
    
    COPD (adult)
    
    Lag 1:0.96 [0.87,1.05]
    
    Lag 2:1.02 [0.93,1.12]
    
    Lag 3: 0.99 [0.90, 1.09]
    Reference: Slaughter et al. (2005,
    0738541
    Period of Study: Jan 1995-Jun 2001
    
    Location: Spokane, WA
    Hospital Admissions and ED visits
    Outcome: All respiratory (460-519)
    Asthma (493)
    COPD (491,492, 494,496)
    Pneumonia (480-487)
    Acute URI not including colds and
    sinusitis (464, 466, 490)
    Age Groups: All, 15+ yr for COPD
    
    Study Design:  Time series
    
    N: 2373 visit records
    
    Statistical Analyses: Poisson
    regression, GLM with natural splines.
    For comparison also used GAM with
    smoothing splines and default
    convergence criteria.
    
    Covariates: Season, temperature,
    relative humidity, day of week
    
    Season: All
    
    Dose-response Investigated?: No
    
    Statistical Package: SAS, SPLUS
    
    Lags Considered: 1 -3 days
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Range (90% of Concentrations):
    4.2-20.2 pg/m3
    
    Monitoring Stations: 1
    
    Notes: Copollutant (correlation):
    PM25
    
    PM1 r =  0.95
    
    PM10r = 0.62
    
    PM10.2.5r = 0.31
    
    CO r = 0.62
    
    Temperature r = 0.21
    PM Increment: 10 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    
    lag:
    ER visits:
    PM25
    All Respiratory
    Lag 1:1.01 [0.98,1.04]
    Lag 2:1.02 [0.99,1.04]
    Lag 3:1.02 [0.99,1.05]
    Acute Asthma
    Lag 1:1.03 [0.98,1.09]
    Lag 2:1.00 [0.95,1.05]
    Lag 3:1.01 [0.96,1.06]
    COPD (adult)
    Lag 1:0.96 [0.89,1.04]
    Lag 2:1.01 [0.93,1.09]
    Lag 3:1.00 [0.93,1.08]
    Hospital Admissions:
    PM25
    All Respiratory
    Lag 1:0.98 [0.94,1.01]
    Lag 2: 0.99 [0.96, 1.03]
    Lag 3:1.01 [0.98,1.05]
    Asthma
    Lag 1:1.01 [0.91,1.11]
    Lag 2:1.03 [0.94,1.13]
    Lag 3:1.02 [0.93,1.13]
    COPD (adult)
    Lag 1:0.99 [0.91,1.08]
    Lag 2:1.06 [0.98,1.16]
    Lag 3:1.03 [0.94,1.12]	
    December 2009
                                    E-291
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Zanobetti and Schwartz
    (2006, 0901951
    Period of Study: 1995-1999
    Location: Boston, MA
    Outcome: Pneumonia (480-487)
    Age Groups: >65 y
    Study Design: Case-crossover, time
    stratified
    N: 24,857 for Pneumonia
    Statistical Analyses: Condition logistic
    regression
    Covariates: Season, long term trend,
    day of-the-wk, mean temperature,
    relative humidity, barometric pressure,
    extinction coefficient
    Season: All yr
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: 0-1
    Notes: Also looked at Ml cohort
    Pollutant: PM25
    Averaging Time: 24 h
    Percentiles (pneumonia cohort):
    25th: 7.23 pg/m3
    50th(Median):11.10
    75th: 16.14
    PM Component: Black Carbon (BC),
    PM non-traffic
    Monitoring Stations: 4-5 monitors
    Copollutant (correlation):
    PM25:
    CO r = 0.52
    N02r = 0.55
    03r = 0.20
    BC r = 0.66
    PM non-traffic r = 0.74
    PM Increment: PM25 lag 0:
    17.17pg/m3
    PM25lagO-1 avg: 16.32 pg/m3
    % change in Pneumonia:
    6.48[1.13,11.43]
    lagO
    5.56[-0.45, 11.27]
    mean lag 1
    Reference: Zanobetti and Schwartz
    (2006, 0901951
    Period of Study: 1995-1999
    Location: Boston, MA
    Outcome: Pneumonia (480-487)
    Age Groups: >65 y
    Study Design: Case-crossover, time
    stratified
    N: 24,857 for Pneumonia
    Statistical Analyses: Condition logistic
    regression
    Covariates: Season, long term trend,
    day of-the-wk, mean temperature,
    relative humidity, barometric pressure,
    extinction coefficient
    Season: All yr
    Dose-response Investigated? No
    Statistical Package: SAS
    Lags Considered: 0-1
    Notes: Also looked at Ml cohort
    Pollutant: BC
    Averaging Time: 24 h
    Percentiles (pneumonia cohort):
    5th: 0.42
    25th: 0.74 pg/m3
    50th(Median):1.15
    75th: 1.72
    95th: 2.83
    PM Component: PM non-traffic
    Monitoring Stations: 4-5 monitors
    Copollutant (correlation):
    BC:
    PM25  r = 0.66
    CO r = 0.82
    N02 r = 0.70
    03  r = -0.25
    PM non-traffic  r = -0.01
    PM Increment: BC lag 0: 2.05 pg/m
    BC lag 0-1 avg: 1.69|jg/m3
    % change in Pneumonia:
    BC-10.76[4.54, 15.89]
    lagO
    BC-11.71[4.79, 17.36]
    mean lag 1
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                                    E-292
    

    -------
    E.3. Short-Term  Exposure and  Mortality
    Table E-16.    Short-term exposure-mortality - PMio.
                 Study
           Design & Methods
            Concentrations
       Effect Estimates (95% Cl)
    Reference: Aga et al. (2003, 0548081
    
    Period of Study: ~5 yr for most cities,
    during the 1990s
    
    Location: 28 European cities
    (APHEA2)
    Outcome: Nonaccidental Mortality
    (<800)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    LOESS
    
    Age Groups: All ages
    
    >65
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): (15, 66)
    
    Copollutant: BS
    
    Note: PM10 only measured in 21 cities.
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    All ages
    Fixed effects: 0.71% (0.60,0.83) 0-1
    Random effects: 0.67% (0.47,0.87) 0-1
    >65
    Fixed effects: 0.79% (0.66,0.92) 0-1
    Random effects: 0.74% (0.52,0.95) 0-1
    Models with effect modifiers (>65)
    24-h N02:
    25th Percentile: 0.30% (0.07,0.53)
    75th Percentile: 0.97% (0.82,1.11)
    24-h temperature:
    25th Percentile: 0.44% (0.25,0.64
    75th Percentile: 0.91% (0.77,1.05
    24-h relative humidity:
    25th Percentile: 0.98% (0.82,1.14
    75th Percentile: 0.52% (0.33,0.71
    Age standardized annual mortality rate:
    25th Percentile: 0.93% (0.77,1.09
    75th Percentile: 0.61% (0.43,0.79
    Proportion individuals >65
    25th Percentile: 0.67% (0.50,0.83
    75th Percentile: 0.85% (0.71,0.99
    Northwest/Central East:
    25th Percentile: 0.81% (0.63,0.98)
    75th Percentile: 0.26% (-0.05,0.57)
    Northwest/South:
    25th Percentile: 0.81% (0.63,0.98
    75th Percentile: 1.04% (0.81,1.27
    Reference: Analitis et al. (2006,
    0881771
    
    Period of Study: NR
    
    Location: 29 European cities
    (APHEA2)
    Outcome: Mortality: Cardiovascular
    diseases (390-459)
    
    Respiratory diseases (460-519)
    
    Study Design: Time-series
    
    Statistical Analyses: 2-stage
    hierarchical modeling
    
    Age Groups: All ages
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Median (SD) unit: Range: 9-64 pg/m3
    
    Range (Min, Max): NR
    
    Copollutant: BS
    
    Note: PM10 only measured in 21 cities.
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Cardiovascular: Fixed effects: (
    (0.47, 0.80) 0-1
    Random effects:
    0.76% (0.47, 1.05)0-1
    0.90% (0.57, 1.23)0-5
    Respiratory: Fixed effects:
    0.58% (0.21, 0.95) 0-1
    Random effects:
    0.71% (0.22,1.20)0-1
    1.24% (0.49, 1.99)0-5
    Reference: Ballester et al. (2002,
    0303711
    
    Period of Study: 1990-1996
    
    Location: 13 Spanish cities
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Cardiovascular diseases (390-459)
    
    Respiratory diseases (460-519)
    
    Study Design: Ecological time series
    
    Statistical Analyses: Poisson GAM,
    LOESS
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): Huelva: 42.5 (15)
    
    Madrid: 37.8 (17.7)
    
    Sevilla:45.1(14)
    
    Range (Min, Max): NR
    
    Copollutant:
    BS
    
    TSP
    
    S02
    
    Note: PMio only measured in 3 cities.
    Increment: 10|jg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Nonaccidental:
    Random effects:
    1.006(0.998,1.015)0-1
    Fixed Effects: 1.005 (1.001,1.010) 0-1
    PM,o+S02:1.013 (1.006, 1.020)0-1
    Cardiovascular:
    1.012(1.005, 1.018)0-1
    PM,o+S02:
    Random effects:
    1.024(1.001, 1.048)0-1
    Fixed effects: 1.021 (1.007,1.035)0-1
    Respiratory:
    1.013(1.001, 1.026)0-1
    PM10+S02:1.003 (0.983, 1.023)0-1
    December 2009
                                  E-293
    

    -------
    Study
    Reference: Bateson and Schwartz
    (2004, 0862441
    
    Period of Study: 1988-1991
    Location: Cook County, Illinois
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Bell et al. (2009, 1910071
    Period of Study: 1987-2000
    Location: 84 U.S. Counties
    
    
    
    
    
    
    
    Reference: Bell et al. (2007, 0932561
    
    Period of Study: 1999-2005
    
    Location: U.S.
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Mortality:
    
    Heart Disease (390-429)
    Respiratory (460-51 9)
    Study Design: Bi-directional case-
    crossover
    
    Statistical Analyses: Conditional
    logistic regression
    Age Groups: 2 65
    Study population:
    65, 1 80 elderly residents with history of
    hospitalization for heart or lung disease
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Mortality
    Study Design: Time-series
    Covariates: Socio-economic
    conditions, long term temperature
    Statistical Analysis: Bayesian
    hierarchical model
    
    Age Groups: All
    
    
    
    
    Outcome: Mortality
    
    Age Groups: 65+
    
    Study Design: Time series
    N:NR
    
    Statistical Analyses: Bayesian
    Hierarchical Regression
    Covariates: Time trend, day of week,
    seasonality, dew point, temperature
    Statistical Package: NR
    Lags Considered: 0-2
    
    
    
    
    
    
    Concentrations1
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SE) unit: 37.6(1 5.5) pg/m3
    Range (Mm, Max): (3.7, 128)
    
    Copollutant: NR
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (SD) Unit: NR
    Range (Min, Max): NR
    Copollutant (correlation): NR
    
    
    
    
    
    
    Pollutant: PM,0
    
    Averaging Time: Daily
    
    Mean: Ni: 0.002
    Min: Ni: 0.003
    
    Max: Ni: 0.021
    Interquartile Range: Ni: 0.001
    Interquartile Range of Percents:
    Ni: 0.01
    Monitoring Stations: NR
    Copollutant: Al, NH4+, As, Ca, Cl, Cu,
    EC, CMC, Fe, Pb, Mg. Ni, N03-, K, Si,
    Na+, S04=, Ti, V, Zn
    Co-pollutant Correlation
    Ni V- 0 4R
    INI, V . U.HO
    Mi Fp1 n ?n
    INI, C\s. U.OU
    Note: Pollutant concentrations available
    for all fractions of PM2 5
    Effect Estimates (95% Cl)
    Increment: 10|jg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    All-cause: 1.1 4% (0.44, 1.85)0-1
    Modification of Effect by Prior Diagnosis
    Myocardial Infarction:
    1.98% (-0.25, 4.26)0-1
    Diabetes: 1.49% (-0.06, 3.07)0-1
    Congestive heart failure:
    1.28% (-0.06, 2.64)0-1
    COPD: 0.58% (-0.82, 2.00) 0-1
    Conduction Disorders:
    0.64% (-0.61, 1.90)0-1
    All other heart or lung diseases:
    0.74% (-0.29, 1.79)0-1
    
    All-cause
    Men
    65: 2.0% (0.3, 3.8) 0-1
    75: 1.5% (-0.2, 3.1)0-1
    85: 0.9% -0.7, 2.5 0-1
    95:0.3% -1.3,1.9 0-1
    All: 1.3% (0.4, 2.3)0-1
    Women
    65: 0.1% (-1.6, 1.9)0-1
    75: 0.7% (-1.1, 2.4) 0-1
    85:1.2% -0.5,3.0)0-1
    95:1.8% 0.03,3.6)0-1
    All: 1.0% (0.1, 1.9) 0-1
    Total
    65: 1.1% (-0.12, 2.3)0-1
    75: 1.1% (-0.1, 2.3) 0-1
    85:1.2% -0.0,2.4)0-1
    95:1.2% 0.0,2.4)0-1
    All: 1.1% (0.4, 1.9)0-1
    Increment: 20% of the population
    acquiring air conditioning
    Percent Change (96% Cl) in
    community-specific PM health effect
    estimates for mortality
    Any AC, including window units
    Yearly health effect: -30.4 (-80.4-19.6)
    Summer health effect: 29.9 (-84-144)
    Winter health effect: -573 (-9100-7955)
    Central AC
    Yearly health effect: -39 (-81. 4-3.3)
    Summer health effect: 20. (-60.3-64.3)
    Winter health effect: -1777 (-5755-2201)
    PM Increment: Interquartile Range in
    the fraction of PM25
    
    Percent Increase in PM10 Health
    Effect (Lower Cl, Upper Cl)
    Ni: 14.8 (-8.1, 37.7), lag 0
    Ni: 14.7 (4.0, 25.3) lag 1
    Ni: 14.7 (1.8, 27.5) lag 2
    HS education: -31. 9 (-82.4, 18.6)
    median income: -12.3 (-62.3, 37.7)
    Percent black: 48.7 (-15.8, 113)
    Percent living in urban area: -20.1 (-
    102,61.7)
    Population: 5.1 (-14.4,24.5)
    Notes: Interquartile ranges in percent
    HS education, median income, percent
    black, percent living in urban area, and
    population are 5.2 %, $9,223, 17.3%,
    11.0%, and 549,283 respectively.
    
    December 2009
    E-294
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Bellini et al. (2007, 0977871  Outcome: Mortality
    Period of Study: 1996-2002
    
    Location: 15 Italian cities
    All-cause (nonaccidental) (<800)
    
    Cardiovascular (390-459)
    
    Respiratory (460-519)
    
    Study Design: Meta-analysis
    
    Statistical Analyses: Poisson GLM
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant:
    S02
    
    
    CO
    
    03
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    All-cause:
    0.31% (-0.19, 0.74)0-1
    Wnter: 0.08% 0-1
    Summer: 1.95%  0-1
    PM,o+03: 0.30%  0-1
    PM,o+N02: 0.08%  0-1
    Respiratory:
    0.54% (-0.91, 1.74) 0-1
    Wnter: 0.27% 0-1
    Summer: 3.61%  0-1
    PM,o+03: 0.55%  0-1
    PMio+N02:0.19%  0-1
    Cardiovascular:
    0.54% (0.02,  1.02)  0-1
    Wnter: 0.20% 0-1
    Summer: 2.79%  0-1
    PM,o+03: 0.57%  0-1
    PMio+N02: 0.39%  0-1
    Reference: Burnett et al. (2004,
    0862471
    
    Period of Study: 1981-1999
    Location: 12 Canadian cities
    
    
    
    
    
    
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Study Design: Time-series
    
    Statistical Analyses: 1. Poisson,
    natural splines
    2. Random effects regression model
    Age Groups: All ages
    
    
    
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    PM25:12.8
    PMi0.2.5: 11.4
    
    Range (Min, Max): NR
    Copollutant (correlation):
    N02
    03
    S02
    CO
    Increment: 10|jg/m3
    
    % Increase (Lower Cl,
    lag:
    
    1981-1999
    
    
    
    Upper Cl)
    
    
    
    
    PM,0: 0.57% (0.05, 0.89) 1
    PM10+N02: 0.07% (-0.44, 0.58) 1
    
    
    
    
    
    
                                                                           Note: PM10 measurement calculated as
                                                                           the sum of PM2 5 and PMi0.2 5
                                                                           measurements.
    Reference: Cakmak et al. (2007,
    0911701
    
    Period of Study: Jan 1997-Dec 2003
    
    Location: Chile-7 cities
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Cardiovascular diseases (390-459)
    
    Respiratory diseases (460-519)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    
    Random effects regression model
    
    Age Groups: All age
    
    <64yr
    
    65-74 yr
    
    75-84 yr
    
    >85yr
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): 84.9
    
    Range (Min, Max): NR
    
    Copollutant (correlation):
    03:r =-0.16-0.13
    
    S02:r = 0.37-0.77
    
    CO: r = 0.49-0.82
    
    Note: Correlations are between
    pollutants for seven monitoring stations.
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Nonaccidental:
    0.97% (-1.09, 2.76 0
    1.31% (-1.56, 3.68 0-5
    PMio+03+S02+CO:
    0.80% (-0.87, 2.28) 0
    
    0.52% (-0.55, 1.51) 0
    0.49% (-0.51, 1.43) 0-5
    65-75:
    1.07% (-1.23, 3.03) 0
    1.31% (-1.57, 3.69) 0-5
    75-84:
    1.41% (-1.71, 3.94) 0
    1.93%  -2.57, 5.30 0-5
    >85:
    1.56% (-1.94, 4.34) 0
    2.14% (-2.97, 5.85) 0-5
    Apr-Sep:
    1.03% (-1.17, 2.93) 0
    1.37% (-1.64, 3.82) 0-5
    Oct-Mar:
    0.07% (-0.07, 0.21) 0
    0.15% (-0.15, 0.44) 0-5
    Cardiovascular:
    1.14% (-1.31, 3.21) 0
    1.49% (-1.82, 4.14) 0-5
    Respiratory:
    2.03% (-2.75, 5.56) 0
    3.11% (-5.25, 8.25) 0-5	
    December 2009
                                    E-295
    

    -------
    Study
    Reference: Chen et al. (2008, 1901061
    Period of Study: 2001 -2004
    Location: Shanghai, China
    
    
    
    
    
    
    
    
    Reference: Daniels et al. (2004,
    087343)
    Period of Study: 1987-1994
    Location: 20 Largest U.S. cities
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome
    (ICD9: 2001; ICD10: 2002-2004):
    Mortality:
    Nonaccidental causes (ICD9 <800;
    ICD10AOO-R99)
    Cardiovascular (ICD9 390-459; I
    CD10IOO-I99)
    Respiratory (ICD9 460-51 9;
    ICD10JOO-J98)
    Study Design: Time-series
    Statistical Analyses: Poisson GAM
    
    Age Groups: All ages
    
    
    
    Outcome:
    Mortality:
    Total (Nonaccidental) mortality
    Cardiovascular-Respiratory (390-448)
    (480-486, 487, 490-496, 507)
    Other-cause mortality
    Study Design: Time-series
    
    Statistical Analyses: City-Specific
    Estimates: Poisson GLM, natural cubic
    splines
    Combined Estimates: 2-stage Bayesian
    hierarchical model
    Age Groups: All ages
    
    
    
    
    
    
    
    
    
    
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD): 102.0
    Range (Mm, Max): (14.0-566.8)
    Copollutant (correlation):
    S02r = 0.64
    N02r = 0.71
    
    
    
    
    
    
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD):
    Los Angeles: 46.0
    New York: 28. 8
    Chicago: 35.6
    Dallas-Ft. Worth: 23.8
    Houston: 30.0
    San Diego: 33.6
    Santa Ana-Anaheim: 37. 4
    Phoenix: 39.7
    Detroit: 40.9
    Miami: 25.7
    Philadelphia: 35.4
    Minneapolis: 26.9
    Seattle: 25.3
    San Jose: 30.4
    Cleveland: 45.1
    San Bernardino: 37.0
    Pittsburgh: 31. 6
    Oakland: 26.3
    Atlanta: 34.4
    San Antonio: 23.8
    
    Effect Estimates (95% Cl)
    Increment: 10|jg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    Nonaccidental
    Single Pollutant: 0.26% (0.14, 0.37)
    PM,o+S02: 0.08% (-0.07, 0.22)
    PM10+N02: 0.01% (-0.14, 0.17)
    PM10+S02+N02: 0.00% (-0.16, 0.16)
    Cardiovascular mortality
    Single Pollutant: 0.27% (0.10, 0.44)
    PM,o+S02: 0.12% (-0.10, 0.34)
    PM,o+N02: 0.01% (-0.22, 0.25)
    PM10+S02+N02: 0.01% (-0.23, 0.25)
    Respiratory mortality
    Single Pollutant: 0.27% (-0.01, 0.56)
    PM10+S02: -0.04% (-0.41, 0.33)
    PM10+N02: -0.05% (-0.45, 0.34)
    PMio+S02+N02: -0.10% (-0.50, 0.30)
    Increment: 10|jg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    Total (nonaccidental):
    0.17% (0.03, 0.30)0
    0.20% (0.07, 0.33) 1
    0.28% (0.16, 0.41)0-1 avg
    
    Cardiovascular-Respiratory:
    0.17% (-0.01, 0.35)0
    0.27% (0.09, 0.44) 1
    0.30% (0.18, 0.51)0-1 avg
    Other-cause:
    0.17% (-0.03, 0.37)0
    0.12% (-0.07, 0.31)1
    0.20% (0.01, 0.38) 0-1 avg
    
    Threshold Models: Total Mortality
    Threshold = 15 pg/m3
    0.30% (0.17, 0.42)0-1 avg
    Threshold = 0 pg/m3
    0.28% (0.16, 0.41)0-1 avg
    Threshold = 20 pg/m3
    0.30% (0.16, 0.43)0-1 avg
    December 2009
    E-296
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: De Leon et al. (2003,
    0556881
    
    Period of Study: Jan 1985-Dec 1994
    
    Location: New York, New York
    Outcome: Mortality:
    
    Circulatory (390-459)
    
    Cancer (140-239)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM
    
    Age Groups: All ages
    
    <75yr
    
    >75yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD):
    
    33.27 pg/m3
    
    IQR (25th, 75th):
    
    (22.67, 40.83)
    
    Copollutant (correlation):
    
    03
    
    CO
    
    S02
    
    NO,
    Increment: 18.16 pg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    All Ages
    Cancer: 1.014 (1.000,1.029)0-1
    -w/out respiratory:
    1.011(0.996,1.026)0-1
    -w/ respiratory:
    1.051(0.998,1.107)0-1
    Circulatory: 1.025 (1.014,1.035)0-1
    -w/out respiratory:
    1.022(1.012,1.033)0-1
    -w/ respiratory:
    1.054(1.022, 1.086)0-1
    <75yr
    Cancer: 1.003 (0.985,1.021)0-1
    -w/out respiratory:
    1.002(0.983,1.022)0-1
    -w/ respiratory:
    1.009(0.943, 1.078)0-1
    Circulatory: 1.027 (1.012,1.043)0-1
    -w/out respiratory:
    1.027(1.011, 1.043)0-1
    -w/ respiratory:
    1.033(0.980,1.089)0-1
    >75yr
    Cancer: 1.033 (1.009,1.058)0-1
    -w/out respiratory:
    1.025(1.000, 1.050)0-1
    -w/ respiratory:
    1.129(1.041,1.225)0-1
    -w/out pneumonia:
    1.026(1.002,1.050)0-1
    -w/ pneumonia:
    1.183(1.058, 1.323)0-1
    -w/out COPD: 1.032 (1.008, 1.057)0-1
    -w/COPD: 1.008 (0.849, 1.197)0-1
    Circulatory: 1.025 (1.012,1.038)0-1
    -w/out respiratory:
    1.022(1.008,1.035)0-1
    -w/ respiratory:
    1.066(1.027,1.106)0-1
    -w/out pneumonia:
    1.023(1.010, 1.036)0-1
    -w/ pneumonia:
    1.078(1.018,1.141)0-1
    -w/out COPD:
    1.025(1.012,1.038)0-1
    -w/COPD:
    1.058(0.991, 1.130)0-1	
    Reference: Dominici et al. (2003,
    0428041
    Period of Study: 1987-1994
    
    Location: 88 U.S. cities
    Outcome: Mortality:
    All-cause (nonaccidental) (<800)
    Cardiac (390-448)
    Respiratory (490-496)
    Influenza (487)
    Pneumonia (480-486, 507)
    Other causes
    Study Design: Time-series
    
    Statistical Analyses: 2-stage Bayesian
    hierarchical model
    
    Age Groups: <65 yr; 65-74 yr; 2 75 yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 10 pg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    
    Cardio-respiratory
    
    0.31% (0.15, 0.50)1
    
    All-cause
    
    0.22% (0.10, 0.38)1
    
    Other causes
    
    0.13% (-0.05, 0.29)1
    Reference: Dominici et al. (2004,
    0591581
    Period of Study: 1987-1994
    
    Location: 90 U.S. cities (NMMAPS)
    Outcome: Mortality:
    
    Total (nonaccidental)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson. GAM,
    GLM
    
    Age Groups: All ages
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    Increment: 10 pg/m3
    
    % Increase (Lower Cl, Upper Cl)
    
    lag:
    
    a = 3
    
    0.2% (0.05, 0.35)
    December 2009
                                    E-297
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Dominici et al. (2004,
    0969511
    
    Period of Study: 1986-1993
    
    Location: 10 U.S. cities
    Outcome: Mortality:
    
    Total (nonaccidental)
    
    Study Design: Time-series
    
    Statistical Analyses: 2-stage Bayesian
    hierarchical model
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Birmingham 34.8
    Canton 28.4
    Colorado Springs 27.5
    Minneapolis/St. Paul 28.1
    Seattle 32.2
    Spokane 42.9
    Chicago 36.3
    Detroit 36.7
    New Haven 28.6
    Pittsburgh 36.0
    New York: 28.8
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    
    Combined analysis:
    
    0.26% (-0.37, 0.65) 0-1
    
    Separate analysis:
    
    0.28% (-0.12, 0.63)0-1
    
    Notes: A separate analysis assumes
    the mortality data does not provide any
    information on the log relative rates of
    mortality.
    Reference: Dominici et al. (2007,
    0973611
    Period of Study: PM10:1987-2000
    
    PM25:1999-2000
    
    Location: 100 U.S. counties
    (NMMAPS)
    Outcome: Mortality:
    
    All-cause (nonaccidental)
    
    Cardiorespiratory
    
    Other-cause
    
    Study Design: Time-series
    
    Statistical Analyses: 2-stage Bayesian
    hierarchical model
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    PM10
    All-cause:
    East:
    1987-1994: 0.29% (0.12, 0.46)1
    1995-2000: 0.13% (-0.19, 0.44)1
    1987-2000: 0.25% (0.11, 0.39)1
    V\fest:
    1987-1994: 0.12% (-0.07, 0.30)1
    1995-2000: 0.18% (-0.07, 0.44)1
    1987-2000: 0.12% (-0.02, 0.26)1
    National:
    1987-1994: 0.21% (0.10, 0.32)1
    1995-2000: 0.18% (0.00, 0.35)1
    1987-2000: 0.19% (0.10, 0.28)1
    Cardiorespiratory:
    East:
    1987-1994: 0.39% (0.16, 0.63)1
    1995-2000: 0.30% (-0.13, 0.73)1
    1987-2000: 0.34% (0.15, 0.54)1
    V\fest:
    1987-1994: 0.17% (-0.07, 0.40)1
    
    
    
    
    1995-2000: 0.13% (-0.23, 0.50
    1987-2000: 0.14% (-0.05, 0.33
    National:
    1987-1994: 0.28% (0.14, 0.43)
    1
    1
    
    1
    1995-2000: 0.21% (-0.03, 0.44)1
    
    
    
    1987-2000: 0.24% (0.13, 0.36)
    Other-cause:
    East:
    1
    
    
    1987-1994: 0.21% (-0.03, 0.44)1
    
    
    
    
    
    1995-2000: 0.00% (-0.49, 0.50
    1987-2000: 0.15% (-0.09, 0.39
    V\fest:
    1987-1994: 0.09% (-0.21, 0.38
    1995-2000: 0.23% (-0.15, 0.62
    1
    1
    
    1
    1
    1987-2000: 0.17% (-0.07, 0.41)1
    
    National:
    
    1987-1994: 0.15% (-0.02, 0.32)1
    1995-2000: 0.17% (-0.07, 0.41)1
    1987-2000: 0.15% (0.00, 0.29)1
    Reference: Dominici et al. (2007, Outcome: Total mortality Pollutant: PM10
    099135)
    Study Design: Time-series Averaging Time: 24-h avg
    Period of Study: 2000-2005
    Statistical Analyses: 2-stage Bayesian Mean (SD): NR
    Location: 72 U.S. counties hierarchical model
    representing 69 communities Range (Mm, Max): NR
    Age Groups: All ages ....... ...,„,„
    Copollutant correlation : NR
    The study does not provide results
    quantitatively.
    
    Note: The study investigated whether
    county-specific short-term effects of
    PM10 on mortality are modified by long-
    term county-specific nickel or vanadium
    PM2 .5 concentrations.
    December 2009
                                    E-298
    

    -------
    Study
    Reference: Fischer et al. (2003,
    0437391
    
    Period of Study: 1986-1994
    Location: The Netherlands
    
    
    
    
    
    
    
    
    
    
    Reference: Fischer et al. (2004,
    0556051
    
    Period of Study: Jun 2003-Aug 2003
    Location: The Netherlands
    
    
    
    Reference: Forastiere et al. (2005,
    0863231
    
    Period of Study: 1998-2000
    Location: Rome, Italy
    
    
    
    
    
    Design & Methods
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Pneumonia (480-486)
    COPD (490-496)
    Cardiovascular (390-448)
    Study Design: Time-series
    Statistical Analyses: Poisson GAM,
    LOESS
    
    Age Groups:
    <45yr
    45-64 yr
    65-74 yr
    >75yr
    
    Outcome: Total mortality
    
    Study Design: NR
    Statistical Analyses: NR
    Age Groups: All ages
    
    
    
    Outcome: Mortality:
    
    Ischemic heart disease (410-414)
    Study Design: Time-stratified case-
    crossover
    Statistical Analyses: Conditional
    logistic regression
    
    Age Groups: >35
    
    
    Concentrations1
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Median (SD) unit: 34
    Range (Min, Max): (10, 278)
    Copollutant:
    BS
    03
    N02
    
    S02
    
    CO
    
    
    
    Pollutant: PM,0
    
    Averaging Time: Wfeekly avg
    Mean (SD):
    2000: 31
    2002: 33
    2003: 35
    IQR (26th, 76th): NR
    Copollutant: 0;
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    CO -I /OO O\
    IQR (25th, 75th):
    (36.0, 65.7)
    Copollutant (correlation):
    PNC1 r = 038
    CO: f = 0.34
    N02:r = 0.45
    S02:r = 0.23
    03:r = 0.13
    Effect Estimates (95% Cl)
    Increment: 80 pg/m3
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Cardiovascular
    <45: 0.906 (0.728, 1.128)0-6
    45-64:1.023(0.945,1.106)0-6
    65-74:1.002(0.945,1.062)0-6
    > 75: 1.016 (0.981, 1.052)0-6
    COPD
    <45: 1.153 (0.587, 2.268)0-6
    45-64:1.139(0.841, 1.541)0-6
    65-74:1.166(0.991,1.372)0-6
    > 75: 1.066 (0.965, 1.178)0-6
    Pneumonia
    <45: 1.427 (0.806, 2.525)0-6
    45-64:1.712(1.042,2.815)0-6
    65-74:1.240 0.879, 1.748 0-6
    > 75: 1.1 23 (1.01 1,1. 247) 0-6
    The study does not present quantitative
    results.
    
    Notes: The study estimates the number
    of deaths attributable to PM10 during the
    summers of 2000, 2002, and 2003.
    
    
    
    Increment: 29.7 pg/m3
    
    % Increase (Lower Cl, Upper Cl)
    lag:
    4. 8% (0.1, 9. 8)0
    4. 9% (0.0, 10.1)1
    
    3. 8% (-1.0, 8.9)2
    2.8% (-2.0, 7.7) 3
    6.1% (0.6, 11.9)0-1
    Reference: Forastiere et al. (2007,
    0907201
    Period of Study: 1998-2001
    
    Location: Rome, Italy
    Outcome: Mortality:
    Natural (<800)
    Malignant neoplasms (140-208)
    Diabetes mellitus (250)
    Hypertensive disease (401-405)
    Previous acute myocardial infarction
    (410, 412)
    Other ischemic heart diseases (411,
    413-414)
    Conduction disorders (426)
    Dysrhythmia (427)
    Heart failure (428)
    Cerebrovascular disease (430-438)
    Peripherical artery disease (440-448)
    COPD (490-496)
    Study Design: Time-stratified case-
    crossover
    
    Statistical Analyses: Conditional
    logistic regression
    
    Age Groups: >35
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean Range (SD) unit: 51.0
    (21.0)fjg/rr?
    
    IQR (25th, 75th):
    
    (36.1,63.0)
    
    Copollutant (correlation): NR
     Increment: 10 pg/m3
    
    % Increase (Lower Cl, Upper Cl)
    
    lag:
    
    Nonaccidental: 1.1% (0.7,1.6)0-1
    
    Low income: 1.9% 0-1
    
    LowSES:1.4% 0-1
    
    High income: 0.0%  0-1
    
    High SES: 0.1% 0-1
    
    Low PM Area: 0.9% (-0.4, 2.1)0-1
    
    High PM Area:  1.47% (0.4, 2.5)0-1
    December 2009
                                    E-299
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Forastiere et al. (2008,
    1869371
    
    Period of Study: 1997-2004
    
    Location: 9 Italian cities
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Study Design: Time-stratified case-
    crossover
    
    Statistical Analyses: Conditional
    logistic regression
    
    Age Groups: >35
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean Range (SD) unit:
    
    35.1-71.5
    
    Range (5th, 95th):
    
    Lowest 5th: 14.3
    
    Highest 95th: 147.0
    
    Copollutant (correlation): NR
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Total: 0.60% (0.31, 0.89) 0-1
    Age
    35-64: -0.20% (-0.77, 0.37) 0-1
    65-74: 0.51% (0.05, 0.98)0-1
    75-84: 0.59%(0.20, 0.97) 0-1
    > 85: 0.97% (0.53, 1.42)0-1
    > 65: 0.75% (0.42, 1.09)
    
    Sex
    Men: 0.72% (0.37, 1.07)0-1
    Vtomen: 0.83% (0.33,1.33)0-1
    
    Median income (by census block)
    Low (<20th percentile):
    0.80% (-0.02, 1.62)0-1
    Mid-low (20th-50th percentile):
    0.68% (0.25, 1.12)0-1
    Mid-high (51st-80th percentile):
    0.85% (0.40, 1.30)0-1
    High (>80th percentile):
    0.30% (-0.25, 0.86) 0-1
    
    Location of death
    Out-of-hospital: 0.71% (0.32,1.11) 0-1
    Discharged 2-28 days before death:
    1.34% (0.49, 2.20) 0-1
    In-hospital: 0.65% (0.33, 0.97) 0-1
    Nursing home: -0.04% (-1.02, 0.95) 0-1
    Reference: Goldberg et al. (2003,
    0352021
    Period of Study: 1984-1993
    Location: Montreal, Quebec, Canada
    
    Reference: Goldberg et al. (2003,
    0352021
    Period of Study: 1984-1993
    Location: Montreal, Quebec, Canada
    
    
    Reference: Kan and Chen (2003,
    0873721
    
    Period of Study: Jan 2000-Dec 2001
    Location: Shanghai, China
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Mortality: Congestive Heart
    Failure (428)
    Study Design: Time-series
    Statistical Analyses: Poisson, natural
    splines
    Age Groups: 2 65
    Outcome: Mortality:
    Diabetes (250)
    Study Design: Time-series
    Statistical Analyses: Poisson, natural
    spline
    Age Groups: 2 65
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Cardiovascular (390-459)
    COPD (490-496)
    
    Study Design: Time-series
    Statistical Analyses: Poisson GAM,
    LOESS
    Age Groups: All ages
    <65yr
    
    65-75 yr
    
    >75yr
    
    
    
    
    
    
    
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD):PM10: 32.2 (17.6)
    IQR(25th, 75th): PM,0: (19.7, 41.1)
    Copollutant (correlation): PM25, TSP,
    Sulfate, CoH, S02, N02, CO, 03
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD):
    PM,0: 32.2 (17.6) pg/m3
    IQR (25th, 75th):
    PM10: (19.7, 41.1)
    Copollutant (correlation): PM25,
    Sulfate, CoH, S02, N02, CO, 03
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD): 91. 14 (51. 85)
    Range (Min, Max): (17.0, 385.0)
    
    Copollutant (correlation):
    S02:r = 0.71
    N02: r = 0.73
    
    
    
    
    
    
    
    
    
    
    
    
    
    This study does not present results
    quantitatively for PM10
    
    
    
    This study does not present results
    quantitatively for PM10
    
    
    
    Increment: 10|jg/m3
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Nonaccidental:
    All ages: 1.003 (1.001, 1.005)0
    <65: 1.001 (0.997, 1.005)0
    65-75:1.005(1.001, 1.008)0
    >75: 1.003 (1.001, 1.006)0
    Cardiovascular:
    All ages: 1.003 (1.000, 1.006)0
    <65: 1.002 (0.994, 1.010)0
    65-75:1.003(0.998, 1.008)0
    >75: 1.003 (1.000, 1.006)0
    
    COPD:
    All ages: 1.005 (0.999, 1.011)0
    <65: 1.004 (0.981, 1.027)0
    65-75:0.996(0.986, 1.007)0
    >75: 1.006 (1.000, 1.012)0
    Multipollutant models:
    S02: 1.001 (0.998, 1.003)0
    N02: 1.001 (0.998, 1.003)0
    S02+N02: 1.000 (0.997, 1.003)0
    December 2009
                                    E-300
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Kan and Chen (2003,
    0873721
    
    Period of Study: Jan 2000-Dec 2001
    
    Location: Shanghai, China
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Cardiovascular (390-459)
    
    COPD (490-496)
    
    Study Design: Case-crossover
    
    Statistical Analyses: Conditional
    logistic regression
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 91.14 (51.85)
    
    IQR (25th, 75th): (54,114)
    
    Copollutant (correlation):
    
    S02:r = 0.71
    
    NO,: r = 0.73
    Increment: 10|jg/m
    
    Odds Ratio (Lower Cl, Upper Cl) lag:
    Nonaccidental:
    Bidirectional referent days:
    7 days: 1.000 (0.9988,1.002) 0-1  ma
    7 and 14 days:
    1.002(1.000, 1.004) 0-1 ma
    7, 14, and 21  days:
    1.003 (1.001, 1.005) 0-1 ma
    Unidirectional referent days:
    7 days: 1.015 (1.012,1.018)0-1 ma
    7 and 14 days: 1.017 (1.015,1.019)
    0-1 ma
    7, 14, and 21  days: 1.019(1.012,
    1.021)  0-1 ma
    Bidirectional referent days (7,14, and
    21 days):
    Cardiovascular:
    1.004 (1.001, 1.007) 0-1 ma
    COPD:
    1.006(0.999, 1.013) 0-1 ma
    Nonaccidental:
    PMio+S02: 0.997 (0.994, 1.025) 0-1 ma
    PM10+N02: 0.997 (0.994, 1.025) 0-1 ma
    PM10+S02+N02: 0.995 (0.992, 1.025)
    0-1 ma
    Reference: Kan et al. (2005, 0875611
    
    Period of Study: Apr 2003-May 2003
    
    Location: Beijing, China
    Outcome: Mortality:
    
    Severe acute respiratory syndrome
    (SARS)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson, GAM,
    smoothing spline
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 149.1 (8.1)
    
    Range (Min, Max): (34, 246)
    
    Copollutant:
    
    S02
    
    N02
    Increment: 10|jg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    0.99(0.96-1.03)0
    1.00(0.97-1.04)1
    1.02  0.98-1.06 2
    1.04(0.99-1.09)3
    1.06(1.00-1.11)4
    1.06  1.00-1.12)5
    1.05(0.98-1.12)6
    Reference: Kan et al. (2007, 0912671
    
    Period of Study: Mar 2004-Dec 2005
    
    Location: Shanghai, China
    Outcome (ICD10): Mortality:
    
    Total (nonaccidental) (AOO-R99)
    Cardiovascular (IOO-I99)
    Respiratory (JOO-J98)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    penalized splines
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 107.9 (2.39) pg/m3
    
    Range (Min, Max): (22.0, 403.0)
    Copollutant (correlation):
     PM10
    PM25:r = 0.84
    PMi0.25:r = 0.88
    03:r = 0.21
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    
    PM10
    
    Total: 0.16% (0.02, 0.30)0-1
    
    Cardiovascular: 0.31% (0.10, 0.53) 0-1
    
    Respiratory: 0.33% (-0.08, 0.75) 0-1
    December 2009
                                    E-301
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Kan et al. (2008,1566211
    
    Period of Study: Jan 2001-Dec 2004
    
    Location: Shanghai, China
    Outcome: Mortality: Total
    (nonaccidental) (AOO-R99)
    
    Cardiovascular (IOO-I99)
    
    Respiratory (JOO-J98)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GLM,
    natural splines
    
    Age Groups:
    All ages;
    
    0-4 yr
    
    5-44 yr
    
    45-64 yr
    
    >65yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD):
    
    Warm season: 87.4 (1.8)
    
    Cool season: 116.7 (2.8)
    
    Entire period: 102.0 (1.7)
    
    Range (Min, Max): NR
    
    Copollutant (correlation):
    S02
    
    N02
    
    03
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Nonaccidental
    Warm season: 0.21 (0.09, 0.3) 0-1
    Cool season: 0.26 (0.22, 0.30) 0-1
    Entire period: 0.25 (0.14, 0.37)0-1
    Female: 0.33 (0.18, 0.48)0-1
    Male: 0.17 (0.03, 0.32)0-1
    5-44: 0.04 (-0.52, 0.59) 0-1
    45-64: 0.17 (-0.11, 0.45) 0-1
    > 65: 0.26 (0.15, 0.38)0-1
    Cardiovascular
    Warm season: 0.22 (-0.14,  0.58) 0-1
    Cool season: 0.25 (0.05, 0.45) 0-1
    Entire period: 0.27 (0.10, 0.44)0-1
    Respiratory
    Warm season: -0.28 (-0.93, 0.38) 0-1
    Cool season: 0.58 (0.25, 0.92) 0-1
    Entire period: 0.27 (-0.01, 0.56) 0-1
    Stratified by Educational Attainment
    Nonaccidental:
    Low: 0.33 (0.19, 0.47)0-1
    High: 0.18 (0.01, 0.36) 0-1
    Cardiovascular:
    Low: 0.30 (0.10, 0.51)0-1
    High: 0.23 (-0.03, 0.50) 0-1
    Respiratory:
    Low: 0.36 (0.00, 0.72) 0-1
    High: 0.02 (-0.43, 0.47) 0-1	
    Reference: Keatinge and Donaldson
    (2006, 0875361
    
    Period of Study: 1991-2002
    
    Location: London, England
    Outcome: Mortality: Total
    (nonaccidental)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM
    
    Age Groups: > 65 yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant:
    03
    
    SO,
    Increment: 10|jg/m
    
    Mortality per 106 (Lower Cl, Upper
    Cl) lag:
    PM10+Temp:
    2.1 (0.9, 3.3) 0-2 avg
    PMio+Temp+Acclim:
    1.6(0.4, 2.8) 0-2 avg
    PM10+Temp+Acclim+Acclim x T:
    1.5(0.3, 2.6) 0-2 avg
    PM10+Temp+Acclim+Acclim x T+Sun:
    1.4(0.2, 2.5) 0-2 avg
    PMio+Temp+Acclim+Acclim x
    T+Sun+Wnd: 0.8 (-0.4,1.9) 0-2 avg
    PM10+Temp+Acclim+Acclim x
    T+Sun+Wind+Abs. Humid.:
    0.8 (-0.3,1.9) 0-2 avg
    PMio+Temp+Acclim+Acclim x
    T+Sun+Wind+Abs. Humid.+ Rain:
    0.9 (-0.3, 2.0) 0-2 avg
    PMio+Temp+Abs. Humid.:
    1.9(0.7, 3.1) 0-2 avg	
    Reference: Kettunen et al. (2007,
    0912421
    Period of Study: 1998-2004
    
    Location: Helsinki, Finland
    Outcome (ICD10): Mortality:
    
    Stroke (160-161,163-164)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    penalized thin-plate splines
    
    Age Groups: > 65
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Median (SD) unit:
    Cold Season: 16.3
    Warm Season:  16.5
    
    Range (Min, Max):
    Cold Season: (3.1,136.7)
    Warm Season:  (3.3, 67.4)
    Copollutant:
    PM25
    PMlO-25
    UFP
    03
    CO
    NO,
    Increment:
    
    Cold Season: 13.8 pg/m3
    
    Warm Season: 9.8 pg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    Cold Season
                                                                                                               -0.56%
                                                                                                               -0.93%
           -3.32, 2.29) 0
           -3.55,1.75)1
                                                                                                               -1.68% (-4.30, 1.00)2
                                                                                                               -1.53% (-4.14, 1.14)3
    
                                                                                                               Warm Season
                                                                                                               10.89% (0.95, 21.81)0
                                                                                                               8.56% (-0.88, 18.90) 1
                                                                                                               2.06% (-6.76, 11.71)2
                                                                                                               -2.89% (-11.32, 6.34)3
    December 2009
                                    E-302
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Kim et al. (2003,1558991
    
    Period of Study: Jan 1995-Dec 1999
    
    Location: Seoul,  Korea
    Outcome (ICD10): Mortality:
    
    Nonaccidental (all except S01-S99,
    T01-T98)
    
    Cardiovascular (IOO-I52)
    
    Respiratory (JOO-J98)
    
    Cerebrovascular (I60-I69)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 69.19 (10.36)
    
    IQR (25th, 75th):
    
    (44.82, 87.95)
    
    Copollutant (correlation): NR
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    All cause:
    2.8% (1.8,  3.7)0
                                                                                                                2.8%
                                                                                                                      1.9, 3.7) 1
                                                                                                                      0.5, 2.3) 2
                                                                                                                3.7% (2.1, 5.4) distributed lag (6-day)
    
                                                                                                                Respiratory:
                                                                                                                8.3% (4.3, 12.5) 0
                                                                                                                6.4%
                                                                                                                6.5%
                                              2.7, 10.2) 1
                                              2.7,10.4)2
                                                                                                                13.9% (6.8, 21.5) distributed lag (6-day)
    
                                                                                                                Pneumonia:
                                                                                                                11.6% (4.2,19.6)0
                                                                                                                9.0%
                                                                                                                7.7%
                                                                                  2.1, 16.3)1
                                                                                  0.8, 15.2) 2
                                                                                                                17.1% (4.1, 31.7) distributed lag (6-day
    
                                                                                                                COPD:
                                                                                                                4.2% (-1.2,  10.0)0
                                                                                                                3.5%
                                                                                                                      -1.5,8.9)1
                                                                                                                      -3.7, 6.8) 2
                                                                                                                12.2% (2.5, 22.9) distributed lag (6-day
                                                                                                                )
                                                                                                                Cardiovascular:
                                                                                                                2.0% (-0.9, 5.0) 0
                                                                                                                3.3%
                                                                                                                2.9%
                                                                                  0.6, 6.2) 1
                                                                                  0.1,5.8)2
                                                                                                                4.4% (-0.6, 9.6) distributed lag (6-day)
    
                                                                                                                Myocardial infarction:
                                                                                                                2.6% (-2.3, 7.8) 0
                                                                                                                5.8%
                                                                                                                5.5%
                                                                                  1.0, 10.7) 1
                                                                                  0.7, 10.6) 2
                                                                                                                4.9% (-3.4,13.9) distributed lag (6-day)
    
                                                                                                                Cerebrovascular:
                                                                                                                3.2% (0.8, 5.5) 0
                                                                                                                3.1%
                                                                                                                2.4%
                                                                                  0.9, 5.3) 1
                                                                                  0.1,4.6)2
                                                                                                                6.3% (2.3,10.5) distributed lag (6-day)
    
                                                                                                                Ischemic stroke:
                                                                                                                -0.6% (-5.6, 4.7) 0
                                                                                                                0.6% (-4.2, 5.7) 1
                                                                                                                -0.1% (-4.9, 5.1)2
                                                                                                                10.3% (1.0, 20.4) distributed lag (6-day)
    Reference: Kim et al. (2004, 0874171
    
    Period of Study: Jan 1997-Dec 2001
    
    Location: Seoul,  Korea
    Outcome: Mortality: Nonaccidental
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    LOESS
    
    Age Groups: All ages
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): 68.23 (36.36) pg/m3
    
    IQR (25th, 75th): (42.56, 84.67)
    
    Copollutant (correlation): NR
    Increment: 42.11 pg/m3
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    
    1.021  (1.009, 1.035)
    December 2009
                                     E-303
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Le Tertre et al. (2005,
    0875601
    
    Period of Study: NR
    
    Location: 21 European cities
    (APHEA-2)
    Outcome: Mortality:                   Pollutant: PMi0
    
    Nonaccidental (<800)                  Averaging Time: 24-h avg
    
    Study Design: Time-series             Mean (SD): NR
    
    Statistical Analyses: Empirical Bayes   Range (Min, Max): NR
    
    Age Groups: All ages                 Copollutant: N0;
                                        Increment: 1.0|jg/m
    
                                        P coefficient (SE) lag:
                                        Athens: 0.001311 (0.0003)
                                        Barcelona: 0.000575 (0.0002)
                                        Basel: 0.000462 (0.0005)
                                        Birmingham: 0.000305 (0.0003)
                                        Budapest: -0.000248 (0.0005)
                                        Cracow: 0.000155 (0.0004)
                                        Erfurt: -0.000465 (0.0004)
                                        Geneva: -0.000059 (0.0005)
                                        Helsinki: 0.000389 (0.0004)
                                        London: 0.000591 (0.0002)
                                        Lyon: 0.001554 (0.0005)
                                        Madrid: 0.000372 (0.0003)
                                        Milan: 0.000901 (0.0002)
                                        Paris: 0.000411 (0.0003)
                                        Prague: 0.000097 (0.0002)
                                        Rome: (0.001333 (0.0003)
                                        Stockholm: 0.000479 (0.0009)
                                        Tel Aviv: 0.000522 (0.0003)
                                        Teplice: 0.000876 (0.0004)
                                        Torino: 0.000938 (0.0002)
                                        Zurich: 0.000365 (0.0004)
                                        Toulouse:  NR (NR)
                                        Overall: 0.00055 (0.000098)
    Reference: Lee et al. (2007, 0930421
    
    Period of Study: Jan 2000-Dec 2004
    
    Location: Seoul,  Korea
    Outcome (ICD10): Mortality:
    
    Nonaccidental (AOO-R99)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM
    
    Age Groups: All ages
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    Mean (SD):
    w/Asian dust days: 70.00 (47.80)
    w/o Asian dust days: 65.77 (33.60)
    Asian dust days only: 188.49 (142.85)
    Copollutant:
    CO
    N02
    S02
    Increment: 41.49 pg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    
    Model with Asian Dust Days
    
    0.7% (0.2,  1.3)1-3
    
    Model without Asian dust days
    
    1.0% (0.2,1.8)1-3
    Reference: Lee and Shaddick (2007,
    1566851
    
    Period of Study: Jan 1993-Dec 1997
    
    Location: Cleveland, Ohio
    
    Detroit, Michigan
    
    Minneapolis, Minnesota
    
    Pittsburgh, Pennsylvania
    Outcome (ICD10): Mortality:
    
    Nonaccidental
    
    Study Design: Time-series
    
    Statistical Analyses:
    1. Bayesian, penalized spline
    
    2. Likelihood, penalized spline
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    Increment: 10|jg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Constant model
    Cleveland: 1.0049
    1
    Detroit: 1.0046
    1
    Minneapolis:  1.0052
    1
    Pittsburgh: 1.0045
    Reference: Martins et al. (2004,
    0874571
    
    Period of Study: Jan 1997-Dec 1999
    
    Location: Sao Paulo, Brazil
    Outcome (ICD10): Mortality:
    
    Respiratory (JOO-J99)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GLM,
    natural cubic splines
    
    Age Groups: > 60
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Cerqueira Cesar: 42.5(22.9)
    Santa Amaro: 49.6(32.1)
    Central: 52.1(23.5)
    Penha: 40.4(23.8)
    Santana:  72.6(24.5)
    Sao Miguel Paulista: 68.6(31.0)
    Range (Min, Max): NR
    The study does not present quantitative
    results.
    December 2009
                                    E-304
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Nawrot et al. (2007,
    0986191
    Period of Study: Jan 1997-Dec 2003
    
    Location: Flanders, Belgium
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Cardiovascular (390-459)
    
    Respiratory (460-519)
    
    Study Design: Time-series
    
    Statistical Analyses: Main analysis:
    Segmented regression models
    
    Sensitivity analysis: Poisson GAM,
    LOESS
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Median (SD) unit:
    
    Winter: 43.3(0.88)
    
    Spring: 39.5(0.88)
    
    summer: 37.7(0.91)
    
    Fall: 37.2(0.88)
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment:
    Main analysis: NR
    Sensitivity analysis: 10 pg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    
    Highest season-specific PM10 quartile
    vs. the lowest season-specific PM10
    quartile
    Summer: 7.8% (6.1,9.6)
    Spring: 6.3% (4.7, 7.8)
    Fall: 2.2% (0.58, 3.8)
    Winter: 1.4% (0.06, 2.9)
    Warm months (Jun, Jul, Aug):
      7.9% (6.2, 9.6)
    Cold months (Dec, Jan, Feb):
      1.5% (0.22, 3.3)
    Intermediate months (Mar, Apr, May,
    Sep, Oct, Nov): 4.2% (2.9, 5.6)
    Warmer Periods (Apr-Sep)
    Nonaccidental: 1.5% (1.1, 2.0)0
    Respiratory: 2.0% (0.6, 3.7) 0
    Cardiovascular: 1.8% (1.1, 2.4)0
    December 2009
                                    E-305
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: O'Neill et al. (2004,
    0874291
    
    Period of Study: 1996-1998
    
    1994-1995
    
    Location: Mexico City,  Mexico
    Outcome: Mortality:
    
    Nonaccidental
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson, natural
    cubic spline
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Range:
    Hi-Vol: 46.3-164.0
    TEOM: 48.2-107.5
    Predicted: 30.2-162.4
    Impactor: 58.4
    
    Range (Min, Max):
    Xalostoc
    Hi-Vol: (40.0, 335.0)
    TEOM: (16.5, 291.2)
    Predicted: (60.6, 320.0)
    
    Tlalnepantla
    Hi-Vol: (25.0, 264.0)
    TEOM: (10.4, 275.9)
    Predicted: (17.7,175.0)
    
    Merced
    Hi-Vol: (17.0, 266.0)
    TEOM: (9.4, 318.7)
    Predicted: (12.3,160.8)
    
    Cerro de la Estrella
    Hi-Vol: (15.0, 292.0)
    TEOM: (13.7, 268.3)
    Predicted: (11.2,154.4)
    
    Pedregal  (1996-1998)
    Hi-Vol: (5.0, 226.0)
    TEOM: (7.8, 264.4)
    Predicted: (-0.5, 86.3)
    
    Pedregal  (1994-1995)
    Hi-Vol: (24.0, 114.0)
    TEOM: (8.7, 152.5)
    Impactor: (15.0,154.0)
    Predicted: (3.9, 75.9)
    Reference: O'Neill et al. (2005,
    0980941
    
    Period of Study: 1996-1998
    
    1996-1999
    
    Location: Mexico City and Monterrey,
    Mexico
    Outcome: Mortality: Nonaccidental
    
    Cardiovascular (390-460)
    
    Respiratory (460-520)
    
    Other-causes
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson, natural
    cubic splines
    
    Age Groups: All ages, 0-15, > 65
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD):
    Mexico City: 75.8 (31.4)
    Monterrey: 50.0 (23.5)
    
    Range (Min, Max):
    Mexico City: (18.0, 233.9)
    Monterrey: (6.2, 230.8)
    
    Copollutant: 0;
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    TEOM
    0.04% (-0.12, 0.20)0
    -0.02%
    -0.01%
    -0.18,0.13)1
    -0.27, 0.25) 2
                                                                                                                 -0.03% (-0.19, 0.13)3
                                                                                                                 -0.03% (-0.19, 0.13)4
                                                                                                                 -0.05% (-0.21, 0.11) 5
                                                                                                                 0.05% (-0.25, 0.35) 0-5
                                                                                                                 Predicted
                                                                                                                 -0.05% (-0.29, 0.19)0
                                                                                                                 0.09% (-0.16, 0.34)1
                                                                                                                 -0.12%
                                                                                                                 -0.02%
                                                                                    -0.43, 0.20) 2
                                                                                    -0.26,0.21)3
                                                                                                                 -0.14% (-0.37, 0.09)4
                                                                                                                 -0.05% (-0.28, 0.18)5
                                                                                                                 0.00% (-0.39, 0.38) 0-5
                                                                                                                 Sierra-Anderson High Volume Air
                                                                                                                 Sampler
                                                                                                                 0.02% (-0.29, 0.32) 0
                                                                                                                 0.13% (-0.27, 0.54)1
                                                                                                                 0.21% (-0.10, 0.52)2
                                                                                                                 0.53% (0.07, 0.99) 3
                                                                                                                 0.11% (-0.20, 0.41)4
                                                                                                                 0.38% (0.07, 0.70) 5
                                                                                                                 GAM: 2 LOESS terms, default
                                                                                                                 convergence
                                                                                                                 1.68% (0.45, 2.93)0
                                                                                                                 -0.36% (-1.56, 0.86)1
                                                                                                                 -0.21% (-1.40, 1.00)2
                                                                                                                 -0.18% (-1.40, 1.05)3
                                                                                                                 1.31% (0.08, 2.55)4
                                                                                                                 1.49% (0.25, 2.73)5
                                                                                                                 1.77% (-0.26, 3.83)0-5
                                                                                                                 Parametric: cubic splines
                                                                                                                 5df
                                                                                                                 1.45% (0.09, 2.83)0
                                                                                                                 -0.71% (-2.06, 0.67) 1
                                                                                                                 -0.59% (-1.95, 0.79)2
                                                                                                                 -0.70% (-2.09, 0.71)3
                                                                                                                 0.92% (-0.46, 2.32) 4
                                                                                                                 1.17% (-0.19, 2.55)5
                                                                                                                 1.17% (-1.54, 3.95)0-5
                                                                                                                 10 df
                                                                                                                 1.60% (0.20, 3.02)0
                                                                                                                 -0.80% (-2.18, 0.60)1
                                                                                                                 -0.73% (-2.11, 0.68) 2
                                                                                                                 -1.05% (-2.49, 0.40)3
    0.64% (-0.79, 2.10
    1.05% (-0.36, 2.48
    0.51% (-2.60, 3.71
    2df
    1.79% (0.48, 3.11)
    -0.09% (-1.38, 1.2:
    0.10% (-1.18, 1.40
    0.20% (-1.10, 1.52
    1.60% (0.30, 2.91)
    1.72% (0.43, 3.04)
    1.90% (-0.36, 4.21
    4
    5
    0-5
    0
    )1
    2
    3
    4
    5
    0-5
    The study focuses on the
    temperature-mortality relationship and
    only includes PM10 as a covariate in
    models.
    December 2009
                                     E-306
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: O'Neill et al. (2008,
    1923141
    Period of Study: Jan 1998-Dec 2002
    
    Location:
    Mexico City, Mexico
    
    Santiago, Chile
    
    Sao Paulo, Brazil
    Outcome:
    
    Study Design: Time-series
    Pollutant: PM,0
    
    Averaging Time: 24 h
    Covariates: Temperature, day of week,  Mean (SD) ug/m3:
    temporal trends, sex
    Statistical Analysis: Poisson
    regression
    
    Statistical Package: S-Plus
    
    Age Groups: Adults over 21 yr
    Mexico City: 53.8 (24.9)
    
    Sao Paulo: 48.9 (21.9)
    
    Santiago: 78.7 (33.0)
    
    Range (Min, Max):
    
    Mexico City: 1.08-192.2
    
    Sao Paulo: 12.0-171.3
    
    Santiago: 8.0-218.6
    
    Copollutant: NR
    Increment: 10|jg/m
    
    Percent increase (96% Cl) in all-
    cause adult mortality (>22yrs) by
    educational level and sex
    Mexico City
    All Adults, Concurrent Day
    None: 0.76 (0.17-1.36)
    Primary: 0.27 (-0.19-0.72)
    Secondary: 0.19 (-0.19-0.57)
    > 12 yr: 0.83 (0.03-1.63)
    All Adults, Lag 1
    None: 0.62 (0.02-1.22)
    Primary: 0.62 (0.17-1.08)
    Secondary: 0.29 (-0.09-0.90)
    > 12 yr: 0.58 (-0.21-1.38)
    All Adults, Distributed Lags 0-5
    None: 0.91 (-0.07-1.89)
    Primary: 0.48 (-0.27-1.24)
    Secondary: 0.27 (-0.36-0.90)
    > 12 yr: 0.75 (-0.49-2.02)
    All Adults, df(yr)
    None: 5.4
    Primary: 6.0
    Secondary: 6.0
    >12yr:3.0
    V\fomen, Concurrent Day
    None: 0.65 (-0.08-1.38)
    Primary: 0.48 (-0.13-1.09)
    Secondary: 0.35 (-0.16-0.86)
    > 12 yr: 1.64 (0.69-2.59)
    Wfomen, Lag 1
    None: 0.62 (-0.12-1.36)
    Primary: 1.03 (0.42-1.64)
    Secondary: 0.59 (0.08-1.11)
    > 12 yr: 1.79 (0.84-2.75)
    Wfomen, Distributed Lags 0-5
    None: 0.46 (-0.74-1.68)
    Primary: 1.39 (0.42-2.36)
    Secondary: 0.51 (-0.30-1.33)
    a 12 yr: 1.71 (0.61-2.83)
    V\fomen, df (yr)
    None: 5.4
    Primary: 4.4
    Secondary: 4.8
    >12yr: 1.0
    Men, Concurrent Day
    None: 0.75 (-0.21-1.72)
    Primary: 0.52 (-0.11-1.15)
    Secondary: 0.56 (0.08-1.05)
    > 12 yr: 1.20 (0.25-2.17)
    Men, Lag 1
    None: 0.45 (-0.51-1.42)
    Primary: 0.70 (0.06-1.34)
    Secondary: 0.47 (-0.02-0.95)
    > 12 yr: 0.74 (-0.22-1.70)
    Men, Distributed Lags 0-5
    None: 1.24 (-0.25-2.75)
    Primary: 0.65 (-0.39-1.69)
    Secondary: 0.88 (0.11-1.66)
    > 12 yr: 1.07 (-0.41-2.57)
    Men, df (yr)
    None: 3.8
    Primary: 5.6
    Secondary: 4.6
    >12yr:3.8
    
    Sao Paulo
    All Adults, Concurrent Day
    None: 0.77 (-0.28-1.82)
    Primary: 1.27 (0.78-1.76)
    Secondary: 0.93 (-0.07-1.94)
    > 12 yr: 2.93 (2.00-2.88)
    All Adults, Lag 1
    None: 0.70 (-0.34-1.76)
    Primary: 1.32 (0.83-1.82)
    Secondary: 1.91 (0.58-2.60)
    > 12 yr: 2.20 (1.27-3.15)	
    December 2009
                                     E-307
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                  All Adults, Distributed Lags 0-5
                                                                                                                  None: 0.76 (-0.91-2.46)
                                                                                                                  Primary: 1.34 (0.55-2.14)
                                                                                                                  Secondary: 1.91 (0.35-2.60)
                                                                                                                  > 12 yr: 2.20 (1.27-3.15)
                                                                                                                  All Adults, df(yr)
                                                                                                                  None: 4.0
                                                                                                                  Primary: 4.0
                                                                                                                  Secondary: 2.8
                                                                                                                  >12yr: 1.6
                                                                                                                  V\fomen, Concurrent Day
                                                                                                                  None: 1.93 (0.87-3.00)
                                                                                                                  Primary: 1.72 (1.04-2.41)
                                                                                                                  Secondary: 0.85 (-0.21-1.92)
                                                                                                                  > 12 yr: 1.84 (0.56-3.13)
                                                                                                                  Wfomen, Lag 1
                                                                                                                  None: 1.41 (0.34-2.48)
                                                                                                                  Primary: 1.64 (0.96-2.33)
                                                                                                                  Secondary: 1.43 (0.36-2.50)
                                                                                                                  > 12 yr: 2.27 (0.99-3.56)
                                                                                                                  Wfomen, Distributed Lags 0-5
                                                                                                                  None: 2.00 (0.40-3.63)
                                                                                                                  Primary: 2.05 (0.96-3.14)
                                                                                                                  Secondary: 1.61 (0.07-3.17)
                                                                                                                  > 12 yr: 3.35 (1.49-5.25)
                                                                                                                  V\fomen, df (yr)
                                                                                                                  None: 2.4
                                                                                                                  Primary: 3.6
                                                                                                                  Secondary: 1.4
                                                                                                                  >12yr:0.8
                                                                                                                  Men, Concurrent Day
                                                                                                                  None:-0.43 (-2.15-1.32)
                                                                                                                  Primary: 1.36 (0.71-2.02)
                                                                                                                  Secondary: 1.74 (0.77-2.72)
                                                                                                                  >12yr:2.81 (1.71-3.92)
                                                                                                                  Men, Lag 1
                                                                                                                  None:-0.44 (-2.17-1.33)
                                                                                                                  Primary: 1.44 (0.79-2.10)
                                                                                                                  Secondary: 1.52 (0.55-2.49)
                                                                                                                  > 12 yr: 1.48 (0.38-2.59)
                                                                                                                  Men, Distributed Lags 0-5
                                                                                                                  None: -0.30 (-3.09-2.56)
                                                                                                                  Primary: 1.67 (0.65-2.70)
                                                                                                                  Secondary: 1.06 (-0.34-2.49)
                                                                                                                  > 12 yr: 3.18 (1.60-4.79)
                                                                                                                  Men, df (yr)
                                                                                                                  None: 4.4
                                                                                                                  Primary: 3.2
                                                                                                                  Secondary: 0.8
                                                                                                                  a 12 yr: 1.2
    
                                                                                                                  Santiago
                                                                                                                  All Adults, Concurrent Day
                                                                                                                  None: 1.44 (0.53-2.36)
                                                                                                                  Primary: 0.06 (-0.21-0.34)
                                                                                                                  Secondary: 0.42 (0.06-0.78)
                                                                                                                  > 12 yr: 1.32 (0.60-2.05)
                                                                                                                  All Adults, Lag 1
                                                                                                                  None: 2.08 (1.16-30.1)
                                                                                                                  Primary: 0.53 (0.25-0.81)
                                                                                                                  Secondary: 0.55 (0.19-0.91)
                                                                                                                  a 12 yr: 1.31 (0.59-2.04)
                                                                                                                  All Adults, Distributed Lags 0-5
                                                                                                                  None: 3.18 (1.60-4.78)
                                                                                                                  Primary: 0.58 (0.10-1.06)
                                                                                                                  Secondary: 1.10 (0.48-1.73)
                                                                                                                  > 12 yr: 2.00 (0.93-3.07)
                                                                                                                  All Adults, df(yr)
                                                                                                                  None: 3.6
                                                                                                                  Primary: 5.6
                                                                                                                  Secondary: 4.0
                                                                                                                  >12yr: 1.6
                                                                                                                  Wfomen, Concurrent Day
                                                                                                                  None: 0.91 (-0.06-1.89)
                                                                                                                  Primary: 0.31 (-0.06-0.68)
                                                                                                                  Secondary: 0.84 (0.33-1.36)
                                                                                                                  > 12 yr: 0.60 (-0.32-1.52)
                 	V\fomen, Lag 1	
    December 2009                                                     E-308
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                   None: 1.58(0.58-2.58)
                                                                                                                   Primary: 0.79 (0.42-1.17)
                                                                                                                   Secondary: 0.76 (0.25-1.28)
                                                                                                                   > 12 yr: 0.53 (-0.39-1.45)
                                                                                                                   V\fomen, Distributed Lags 0-5
                                                                                                                   None: 1.15 (-0.48-2.80)
                                                                                                                   Primary: 1.05 (0.41-1.69)
                                                                                                                   Secondary: 1.29 (0.40-2.19)
                                                                                                                   > 12 yr: 1.06 (-0.27-2.41)
                                                                                                                   Wfomen, df (yr)
                                                                                                                   None: 2.6
                                                                                                                   Primary: 4.8
                                                                                                                   Secondary: 4.4
                                                                                                                   a 12 yr: 1.0
                                                                                                                   Men, Concurrent Day
                                                                                                                   None: 0.05 (-1.02-1.12)
                                                                                                                   Primary:-0.11  (-0.5-0.28)
                                                                                                                   Secondary: 0.18 (-0.31-0.68)
                                                                                                                   > 12 yr: 1.52 (0.70-2.35)
                                                                                                                   Men, Lag 1
                                                                                                                   None: 0.61 (-0.44-1.68)
                                                                                                                   Primary: 0.23 (-0.16-0.62)
                                                                                                                   Secondary: 0.49 (0.00-0.98)
                                                                                                                   > 12 yr: 1.03 (0.21-1.86)
                                                                                                                   Men, Distributed Lags 0-5
                                                                                                                   None: 2.08 (0.28-3.91)
                                                                                                                   Primary: 0.16 (-0.50-0.82)
                                                                                                                   Secondary: 1.27 (0.43-2.12)
                                                                                                                   > 12 yr: 1.98 (0.76-3.20)
                                                                                                                   Men, df (yr)
                                                                                                                   None: 2.8
                                                                                                                   Primary: 4.8
                                                                                                                   Secondary: 4.4
                                                                                                                   >12yr: 1.6
                                                                                                                   Percent increase (96% Cl) in all-
                                                                                                                   cause adult mortality (>66yrs) by
                                                                                                                   educational level and sex
                                                                                                                   Mexico City
                                                                                                                   All Adults, Concurrent Day
                                                                                                                   None: 0.41 (-0.25-1.08)
                                                                                                                   Primary: 0.40 (-0.15-0.95)
                                                                                                                   Secondary: 0.50 (-0.01-1.01)
                                                                                                                   a 12 yr: 1.51 (0.39-2.63)
                                                                                                                   All Adults, Lag 1
                                                                                                                   None: 0.20 (-0.47-0.87)
                                                                                                                   Primary: 0.80 (0.24-1.36)
                                                                                                                   Secondary: 0.60 (0.09-1.12)
                                                                                                                   > 12 yr: 1.09 (-0.02-2.22)
                                                                                                                   All Adults, Distributed Lags 0-5
                                                                                                                   None: 0.27 (-0.83-1.38)
                                                                                                                   Primary: 0.99 (0.07-1.91)
                                                                                                                   Secondary: 0.30 (-0.56-1.16)
                                                                                                                   > 12 yr: 1.83 (0.09-3.59)
                                                                                                                   All Adults, df(yr)
                                                                                                                   None: 5.6
                                                                                                                   Primary: 5.4
                                                                                                                   Secondary: 6.0
                                                                                                                   >12yr:3.2
                                                                                                                   Wfomen, Concurrent Day
                                                                                                                   None: 0.49 (-0.30-1.29)
                                                                                                                   Primary: 0.39 (-0.33-1.11)
                                                                                                                   Secondary: 0.52 (-0.16-1.20)
                                                                                                                   > 12 yr: 1.29 (0.12-2.48)
                                                                                                                   V\fomen, Lag 1
                                                                                                                   None: 0.73 (-0.07-1.54)
                                                                                                                   Primary: 1.24 (0.52-1.97)
                                                                                                                   Secondary: 0.55 (-0.13-1.23)
                                                                                                                   > 12 yr: 1.50 (0.32-2.70)
                                                                                                                   V\fomen, Distributed Lags 0-5
                                                                                                                   None: 0.75 (-0.56-2.08)
                                                                                                                   Primary: 1.43 (0.29-2.59)
                                                                                                                   Secondary: 0.06 (-1.01-1.15)
                                                                                                                   > 12 yr: 1.48 (0.10-2.87)
                                                                                                                   Wfomen, df (yr)
                                                                                                                   None: 5.4
                                                                                                                   Primary: 4.2
                 	Secondary: 4.8	
    December 2009                                                     E-309
    

    -------
                  Study                       Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                                   >12yr:0.6
                                                                                                                   Men, Concurrent Day
                                                                                                                   None: 0.90 (-0.23-2.04)
                                                                                                                   Primary: 0.37 (-0.40-1.16)
                                                                                                                   Secondary: 0.78 (0.07-1.49)
                                                                                                                   > 12 yr: 1.66 (0.30-3.04)
                                                                                                                   Men, Lag 1
                                                                                                                   None:-0.15 (-1.27-0.98)
                                                                                                                   Primary: 0.26 (-0.53-1.05)
                                                                                                                   Secondary: 0.93 (0.22-1.65)
                                                                                                                   > 12 yr: 0.95 (-0.41-2.32)
                                                                                                                   Men, Distributed Lags 0-5
                                                                                                                   None: 0.80 (-0.95-2.58)
                                                                                                                   Primary: 0.29 (-0.99-1.58)
                                                                                                                   Secondary: 1.06 (-0.08-2.21)
                                                                                                                   > 12 yr: 1.76 (-0.35-3.91)
                                                                                                                   Men, df (yr)
                                                                                                                   None: 3.8
                                                                                                                   Primary: 5.6
                                                                                                                   Secondary: 4.6
                                                                                                                   >12yr:3.8
    
                                                                                                                   Sao Paulo
                                                                                                                   All Adults, Concurrent Day
                                                                                                                   None: 0.60 (-0.48-1.70)
                                                                                                                   Primary: 0.59 (1.00-2.19)
                                                                                                                   Secondary: 1.21 (-0.01-2.44)
                                                                                                                   > 12 yr: 2.80 (1.67-3.94)
                                                                                                                   All Adults, Lag 1
                                                                                                                   None: 0.62 (-0.47-1.72)
                                                                                                                   Primary: 1.48 (0.89-2.07)
                                                                                                                   Secondary: 2.31 (1.08-3.55)
                                                                                                                   > 12 yr: 2.52 (1.40-3.66)
                                                                                                                   All Adults, Distributed Lags 0-5
                                                                                                                   None: 0.91 (-0.84-2.69)
                                                                                                                   Primary: 1.73 (0.79-2.67)
                                                                                                                   Secondary: 3.25 (1.39-5.16)
                                                                                                                   > 12 yr: 3.63 (2.01-5.29)
                                                                                                                   All Adults, df(yr)
                                                                                                                   None: 4.0
                                                                                                                   Primary: 3.8
                                                                                                                   Secondary: 2.6
                                                                                                                   >12yr: 1.6
                                                                                                                   V\fomen, Concurrent  Day
                                                                                                                   None: 1.82 (0.71-2.94)
                                                                                                                   Primary: 1.84 (1.05-2.64)
                                                                                                                   Secondary: 0.62 (-0.55-1.81)
                                                                                                                   > 12 yr: 1.00 (-0.27-2.29)
                                                                                                                   Wfomen, Lag 1
                                                                                                                   None: 1.36 (0.25-2.49)
                                                                                                                   Primary: 1.76 (0.97-2.56)
                                                                                                                   Secondary: 1.57 (0.39-2.76)
                                                                                                                   > 12 yr: 1.39 (0.12-2.68)
                                                                                                                   Wfomen, Distributed Lags 0-5
                                                                                                                   None: 1.80 (0.12-3.51)
                                                                                                                   Primary: 1.97 (0.73-3.22)
                                                                                                                   Secondary: 1.89 (0.19-3.61)
                                                                                                                   > 12 yr: 2.53 (0.70-4.40)
                                                                                                                   V\fomen, df (yr)
                                                                                                                   None: 2.4
                                                                                                                   Primary: 3.4
                                                                                                                   Secondary: 1.2
                                                                                                                   >12yr:0.8
                                                                                                                   Men, Concurrent Day
                                                                                                                   None:-0.67 (-2.50-1.19)
                                                                                                                   Primary: 1.82 (1.00-2.65)
                                                                                                                   Secondary: 2.46 (1.31-3.63)
                                                                                                                   > 12 yr: 1.73 (0.47-3.00)
                                                                                                                   Men, Lag 1
                                                                                                                   None:-0.59 (-2.42-1.26)
                                                                                                                   Primary: 1.59 (0.78-2.41)
                                                                                                                   Secondary: 2.64 (1.49-3.80)
                                                                                                                   > 12 yr: 0.89 (-0.35-2.15)
                                                                                                                   Men, Distributed Lags 0-5
                                                                                                                   None: 1.50 (-1.52-4.60)
                                                                                                                   Primary: 2.46 (1.20-3.74)
                                                                                                                   Secondary: 2.24 (0.56-3.95)
                 	> 12 yr: 1.45 (-0.34-3.29)	
    December 2009                                                     E-310
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                   Men, df (yr)
                                                                                                                   None: 4.6
                                                                                                                   Primary: 3.0
                                                                                                                   Secondary: 0.8
                                                                                                                   a 12 yr: 1.0
    
                                                                                                                   Santiago
                                                                                                                   All Adults, Concurrent Day
                                                                                                                   None: 1.49 (0.54-2.45)
                                                                                                                   Primary: 0.28 (-0.03-0.59)
                                                                                                                   Secondary: 0.58 (0.13-1.04)
                                                                                                                   > 12 yr: 2.32 (1.50-3.15)
                                                                                                                   All Adults, Lag 1
                                                                                                                   None: 2.20 (1.24-3.17)
                                                                                                                   Primary: 0.74 (0.43-1.05)
                                                                                                                   Secondary: 0.64 (0.20-1.11)
                                                                                                                   > 12 yr: 2.20 (1.36-3.04)
                                                                                                                   All Adults, Distributed Lags 0-5
                                                                                                                   None: 3.21 (1.54-4.90)
                                                                                                                   Primary: 0.92 (0.38-1.46)
                                                                                                                   Secondary: 1.46 (0.67-2.25)
                                                                                                                   > 12 yr: 4.02 (2.78-5.27)
                                                                                                                   All Adults, df(yr)
                                                                                                                   None: 3.8
                                                                                                                   Primary: 5.2
                                                                                                                   Secondary: 4.0
                                                                                                                   >12yr: 1.8
                                                                                                                   Wfomen, Concurrent Day
                                                                                                                   None: 1.39 (0.41-2.39)
                                                                                                                   Primary: 0.4 (0.01-0.8)
                                                                                                                   Secondary: 0.91 (0.29-1.53)
                                                                                                                   > 12 yr: 0.87 (-0.02-1.78)
                                                                                                                   Wfomen, Lag 1
                                                                                                                   None: 1.83 (0.83-2.85)
                                                                                                                   Primary: 0.98 (0.58-1.38)
                                                                                                                   Secondary: 0.73 (0.11-1.35)
                                                                                                                   > 12 yr: 0.76 (-0.15-1.68)
                                                                                                                   V\fomen, Distributed Lags 0-5
                                                                                                                   None: 2.47 (0.85-4.11)
                                                                                                                   Primary: 1.2 (0.52-1.88)
                                                                                                                   Secondary: 1.71 (0.65-2.78)
                                                                                                                   > 12 yr: 0.87 (-0.02-1.78)
                                                                                                                   Wfomen, df (yr)
                                                                                                                   None: 2.4
                                                                                                                   Primary: 4.8
                                                                                                                   Secondary: 4.4
                                                                                                                   >12yr:0.6
                                                                                                                   Men, Concurrent Day
                                                                                                                   None: 0.54 (-0.51-1.61)
                                                                                                                   Primary: 0.34 (-0.12-0.80)
                                                                                                                   Secondary: 0.25 (-0.40-0.91)
                                                                                                                   > 12 yr: 1.97 (1.09-2.86)
                                                                                                                   Men, Lag  1
                                                                                                                   None: 0.84 (-0.21-1.91)
                                                                                                                   Primary: 0.43 (-0.03-0.89)
                                                                                                                   Secondary: 0.61 (-0.04-1.26)
                                                                                                                   > 12 yr: 1.57 (0.67-2.46)
                                                                                                                   Men, Distributed Lags 0-5
                                                                                                                   None: 2.41 (0.64-4.22)
                                                                                                                   Primary: 0.80 (0.02-1.59)
                                                                                                                   Secondary: 1.58 (0.45-2.71)
                                                                                                                   > 12 yr: 2.99 (1.66-4.33)
                                                                                                                   Men, df (yr)
                                                                                                                   None: 2.0
                                                                                                                   Primary: 4.4
                                                                                                                   Secondary: 4.4
                 	>12yr: 1.8	
    December 2009                                                     E-311
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
    Reference: Peng et al. (2005, 0874631  Outcome: Mortality:
    
    Period of Study: 1987-2000           Nonaccidental
    
    Location: 100 U.S. cities (NMMAPS)    Study Design: Time-series
    
                                       Statistical Analyses: Bayesian
                                       semiparametric hierarchical models
    
                                       Age Groups: All ages
                                Pollutant: PM,0
    
                                Averaging Time: 24-h avg
    
                                Median (SD) unit: 27.1
    
                                Range (Mm, Max): (13.2, 48.7)
    
                                Copollutant (correlation): NR
                               Increment: 10|jg/m
    
                               % Increase (Lower Cl, Upper Cl) lag:
                               Winter:
                               -0.4% (-0.30, 0.21)0
                               0.15% (-0.08, 0.39  1
                               0.10% (-0.13, 0.33  2
                               Spring:
                               0.32% (0.08, 0.56) 0
                               0.14% (-0.14, 0.42)1
                               0.05% (-0.21, 0.32) 2
                               Summer:
                               0.13% (-0.11,0.37)0
                               0.36% (0.11, 0.61)1
                               -0.03% (-0.27, 0.21)2
                               Fall:
                               0.05% (-0.16, 0.25)0
                               0.14% (-0.06, 0.34  1
                               0.13% (-0.08, 0.35  2
                               All Seasons:
                               0.09% (-0.01, 0.19)0
                               0.19% (0.10, 0.28)1
                               0.08% (-0.03, 0.19)2
                               PM10 only (46 cities):
                               Winter: 0.15% (-0.16, 0.45)1
                               Spring: 0.13% (-0.21, 0.48)1
                               Summer: 0.30% (-0.10, 0.69)1
                               Fall: 0.07% (-0.23, 0.37) 1
                               PM10 +03 (46 cities):
                               Wnter: 0.18% (-0.16, 0.52)1
                               Spring: 0.10% (-0.30, 0.49)1
                               Summer: 0.33% (-0.14, 0.81)1
                               Fall: 0.08% (-0.25, 0.41)1
                               PM10 + 03 (45 cities):
                               Wnter: 0.13% (-0.24, 0.49)1
                               Spring: 0.1% 9(-0.18, 0.56)1
                               Summer: 0.28% (-0.13, 0.70)1
                               Fall:-0.01% (-0.34, 0.31)1
                               PM10 + N02 (46 cities):
                               Wnter: 0.21% (-0.18, 0.60)1
                               Spring: 0.19% (-0.17, 0.54)1
                               Summer: 0.34% (0.01, 0.68)1
                               Fall: 0.13% (-0.12, 0.39)1
    Reference: Penttinen et al. (2004,
    0874321
    
    Period of Study: 1988-1996
    Location: Helsinki, Finland
    
    
    
    
    
    
    Reference: Qian et al. (2007, 0930541
    Period of Study: 2001 -2004
    Location: Wuhan, China
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    Cardiovascular (390-459)
    Respiratory (460-51 9)
    Study Design: Time-series
    Statistical Analyses: Poisson GAM,
    LOESS
    Age Groups:
    15-64yr
    65-74 yr
    >75yr
    Outcome: Mortality:
    Total (nonaccidental) (<800)
    Cardiovascular (390-459)
    Stroke (430-438)
    
    Cardiac Diseases (390-398)
    Respiratory (460-51 9)
    Cardiopulmonary
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    natural splines
    Age Groups: All ages
    
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Median (SD) unit: 21 |jg/m;
    Range (Min, Max): (0.2, 213)
    Copollutant (correlation):
    rv r- nnQ
    W3. I U.UiJ
    N02:r = 0.50
    CO: r = 0.45
    en,' r- Dfil
    OW2. I U.U I
    TSP:r = 0.72
    
    
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD): 141. 8 3
    Range (Min, Max): (24.8, 477.8)
    
    Copollutant (correlation):
    N02
    S02
    03
    
    
    
    
    
    Increment: 10|jg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    Total (nonaccidental)
    -0.23% (-1.47, 1.01)0
    0.88% (-0.32, 2.08) 1
    0.11 (-0.51, 0.73) 0-3 avg
    Cardiovascular
    -1.22% (-3.00, 0.56)0
    0.63% (-1.09, 2.35)1
    0.08% (-0.96, 0.81) 0-3 avg
    Respiratory
    3.94% (0.01, 7.87)0
    3.96% (0.11, 7.81)1
    2. 13% (0.03, 4. 22) 0-3 avg
    Increment: 10|jg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    Nonaccidental
    0.36% (0.19, 0.53)0
    0.28% (0.12, 0.45)1
    0.43% (0.24, 0.62) 0-1
    0.08% (-0.15, 0.31)0-4
    <45yr
    0.28% (-0.26, 0.82 0
    0.45% (-0.06, 0.96 1
    0.53% (-0.08, 1.13)0-1
    0.41% (-0.31, 1.13)0-4
    >45yr
    0.36% (0.19, 0.54)0
    0.27% (0.10, 0.44)1
    0.42% (0.22, 0.62) 0-1
    0.05% (-0.18, 0.29)0-4
    <65yr
    December 2009
                            E-312
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                           ~                                                                  0.20% (-0.08, 0.49) 0
                                                                                                               0.25% (-0.03, 0.52) 1
                                        >45yr                                                                  0.33% (0.01, 0.66) 0-1
                                                                                                               0.01% (-0.38, 0.39)0-4
                                        <65 yr                                                                  > 65 yr
                                                                                                               0.41% (0.21, 0.61)0
                                        Ł65y                                                                  0.30% (0.10,0.49)1
                                                                                                               0.46% (0.24, 0.69) 0-1
                                                                                                               0.10% (-0.16, 0.37)0-4
    
                                                                                                               Cardiovascular
                                                                                                               0.51% (0.28, 0.75)0
                                                                                                               0.35% (0.12, 0.58)1
                                                                                                               0.58% (0.31, 0.84) 0-1
                                                                                                               0.35% (0.05, 0.66) 0-4
                                                                                                               <45yr
                                                                                                               0.59% (-0.62, 1.82 0
                                                                                                               0.93% (-0.22, 2.08 1
                                                                                                               1.07% (-0.27, 2.42)0-1
                                                                                                               1.15% (-0.40, 2.72)0-4
                                                                                                               >45yr
                                                                                                               0.51% (0.27, 0.75)0
                                                                                                               0.33% (0.10, 0.56)1
                                                                                                               0.56% (0.30, 0.83) 0-1
                                                                                                               0.33% (0.02, 0.63) 0-4
                                                                                                               <65yr
                                                                                                               0.27% (-0.23, 0.76) 0
                                                                                                               0.30% (-0.16, 0.77)1
                                                                                                               0.42% (-0.12, 0.97
    0-1
    0-4
                                                                                                               0.43% (-0.19, 1.06
                                                                                                               >65yr
                                                                                                               0.57% (0.31, 0.83)0
                                                                                                               0.36% (0.11, 0.61)1
                                                                                                               0.61% (0.32, 0.90)0-1
                                                                                                               0.33% (0.00, 0.67) 0-4
    
                                                                                                               Stroke
                                                                                                               0.44% (0.16, 0.72)0
                                                                                                               0.41% (0.14, 0.68)1
                                                                                                               0.58% (0.27, 0.89) 0-1
                                                                                                               0.45% (0.09, 0.81)0-4
                                                                                                               <45yr
                                                                                                               1.18% (-0.45, 2.83)0
                                                                                                               1.66% (0.11, 3.24)1
                                                                                                               1.91% (0.10, 3.75)0-1
                                                                                                               2.72% (0.58, 4.89) 0-4
                                                                                                               >45yr
                                                                                                               0.42% (0.14, 0.70)0
                                                                                                               0.37% (0.10, 0.65)1
                                                                                                               0.55% (0.23, 0.86) 0-1
                                                                                                               0.39% (0.03, 0.76) 0-4
                                                                                                               <65yr
                                                                                                               0.26% (-0.35, 0.87 0
                                                                                                               0.38% (-0.20, 0.96 1
                                                                                                               0.48% (-0.19, 1.16)0-1
                                                                                                               0.57% (-0.21, 1.35)0-4
                                                                                                               >65yr
                                                                                                               0.49% (0.17, 0.80)0
                                                                                                               0.41% (0.11, 0.72)1
                                                                                                               0.61% (0.26, 0.96)0-1
                                                                                                               0.42% (0.02, 0.83) 0-4
    
                                                                                                               Cardiac
                                                                                                               0.49% (0.08, 0.89) 0
                                                                                                               0.28% (-0.11, 0.67)1
                                                                                                               0.49% (0.04, 0.94) 0-1
                                                                                                               0.22% (-0.29, 0.74) 0-4
                                                                                                               <45yr
                                                                                                               0.25% (-1.64, 2.17 0
                                                                                                               0.56% (-1.22, 2.38 1
                                                                                                               0.61% (-1.47, 2.74)
                                                                                                               0-1
                                                                                                               -0.42% (-2.80, 2.02) 0-4
                                                                                                               >45yr
                                                                                                               0.49% (0.09, 0.91)0
                                                                                                               0.27% (-0.12, 0.66)1
                                                                                                               0.48% (0.03, 0.94) 0-1
                                                                                                               0.25% (-0.27, 0.77) 0-4
    December 2009                                                    E-313
    

    -------
                  Study                      Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                              <65yr
                                                                                                              0.00% (-0.89, 0.90  0
                                                                                                              0.12% (-0.73, 0.98  1
                                                                                                              0.13% (-0.86, 1.13)0-1
                                                                                                              0.05% (-1.08, 1.20)0-4
                                                                                                              >65yr
                                                                                                              0.60% (0.17, 1.03)0
                                                                                                              0.32% (-0.10, 0.74)1
                                                                                                              0.57% (0.09, 1.06)0-1
                                                                                                              0.26% (-0.29, 0.82) 0-4
    
                                                                                                              Respiratory
                                                                                                              0.71% (0.20, 1.23)0
                                                                                                              0.63% (0.13, 1.13)1
                                                                                                              0.86% (0.28, 1.44)0-1
                                                                                                              0.19% (-0.48, 0.87)0-4
                                                                                                              <45yr
                                                                                                              1.74% (-1.28, 4.86)0
                                                                                                              2.52% (-0.30, 5.42) 1
                                                                                                              2.95% (-0.41, 6.42
              0-1
              0-4
                                                                                                              3.47% (-0.61, 7.73
                                                                                                              >45yr
                                                                                                              0.69% (0.18, 1.21)0
                                                                                                              0.58% (0.09, 1.08)1
                                                                                                              0.81% (0.23, 1.39)0-1
                                                                                                              0.13% (-0.54, 0.80)0-4
                                                                                                              <65yr
                                                                                                              0.06% (-1.30, 1.43)0
                                                                                                              -0.53%
                                                                                                              -0.32%
    -1.83,0.79)1
    -1.84,1.22)0-1
                                                                                                              -0.72% (-2.47, 1.05)0-4
                                                                                                              >65yr
                                                                                                              0.79% (0.27, 1.31)0
                                                                                                              0.76% (0.26, 1.26)1
                                                                                                              0.99% (0.41, 1.57)0-1
                                                                                                              0.30% (-0.38, 0.98) 0-4
    
                                                                                                              Cardiopulmonary
                                                                                                              0.46% (0.23, 0.69) 0
                                                                                                              0.35% (0.13, 0.57)1
                                                                                                              0.53% (0.28, 0.79) 0-1
                                                                                                              0.11% (-0.19, 0.42)0-4
                                                                                                              <45yr
                                                                                                              0.71% (-0.48, 1.92)0
                                                                                                              1.26% (0.14, 2.4)1
                                                                                                              1.39% (0.06, 2.74)0-1
                                                                                                              1.41% (-0.18, 3.03)0-4
                                                                                                              >45yr
                                                                                                              0.45% (0.23, 0.68) 0
                                                                                                              0.32% (0.10, 0.54)1
                                                                                                              0.51% (0.25, 0.77)0-1
                                                                                                              0.08% (-0.23, 0.38) 0-4
                                                                                                              <65yr
                                                                                                              0.14% (-0.34, 0.61  0
                                                                                                              0.15% (-0.30, 0.61  1
                                                                                                              0.23% (-0.30, 0.76) 0-1
                                                                                                              0.11% (-0.52, 0.74)0-4
                                                                                                              >65yr
                                                                                                              0.53% (0.28, 0.78) 0
                                                                                                              0.39% (0.15, 0.63)1
                                                                                                              0.60% (0.32, 0.88) 0-1
                                                                                                              0.11% (-0.22, 0.45)0-4
    
                                                                                                              Two-pollutant Models
                                                                                                              Nonaccidental
                                                                                                              PM10+N02: 0.14% (-0.07, 0.36) 0
                                                                                                              PM10+S02: 0.37% (0.20, 0.55) 0
                                                                                                              PM,o+03: 0.34% (0.17, 0.51)0
    
                                                                                                              Cardiovascular
                                                                                                              PM,o+N02: 0.34% (0.04, 0.63) 0
                                                                                                              PM10+S02: 0.53% (0.28, 0.77) 0
                                                                                                              PM10+03: 0.50% (0.26, 0.74) 0
    
                                                                                                              Stroke
                                                                                                              PM,o+N02: 0.28% (-0.07, 0.63) 0
                                                                                                              PM,o+S02: 0.49% (0.21, 0.78)0
                                                                                                              PM10+03: 0.44 (0.16, 0.72)0
    December 2009                                                   E-314
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                               Cardiac
                                                                                                               PM10+N02: 0.24% (-0.27, 0.75) 0
                                                                                                               PM10+S02: 0.43 (0.01, 0.84)0
                                                                                                               PM,o+03: 0.44% (0.03, 0.85) 0
    
                                                                                                               Respiratory
                                                                                                               PM,o+N02: 0.46% (-0.19, 1.12)0
                                                                                                               PM10+S02: 0.64% (0.11, 1.18)0
                                                                                                               PM10+03: 0.67% (0.15, 1.20)0
    
                                                                                                               Cardiopulmonary
                                                                                                               PM,o+N02: 0.26% (-0.02, 0.55) 0
                                                                                                               PM,o+S02: 0.46% (0.23, 0.70) 0
                                                                                                               PM10+03: 0.44% (0.21, 0.67)0
    Reference: Qian et al. (2008,1568941
    
    Period of Study: Jul 2001-Jun 2004
    
    Location: Wuhan,  China
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    
    Cardiovascular (390-459)
    
    Stroke (430-438)
    
    Cardiac diseases (390-398, 410-429)
    
    Respiratory (460-519)
    
    Cardiopulmonary (390-459, 460-519)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GLM,
    natural  splines and penalized splines
    
    Age Groups: All ages
    
    <65yr
    
    >65yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Normal temperature: 145.7 (64.6)
    Low temperature: 117.3 (49.5)
    High temperature: 96.3 (27.9)
    Range (Min, Max): NR
    Copollutant (correlation):
    Normal temperature:
    N02:r = 0/72
    S02:r = 0.59
    03:r = 0.06
    Low temperature:
    N02:r = 0.83
    S02:r = 0.74
    03:r = 0.19
    High temperature:
    N02:r = 0.68
    S02:r = 0.15
    03:r = 0.65
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Nonaccidental:
    Normal:
    All ages: 0.36 (0.17, 0.56)0-1
    <65: 0.23 (-0.10, 0.56)0-1
    > 65: 0.51 (0.18, 0.64)0-1
    PM,o+N02: 0.07 (-0.17, 0.30)0-1
    PM10+S02: 0.27 (0.06, 0.47) 0-1
    PM10+03: 0.38 (0.18,  0.58)0-1
    Low:
    All ages: 0.62 (-0.09,1.34)0-1
    <65:1.78 (0.52, 3.05)0-1
    > 65: 0.22 (-0.61, 1.05)0-1
    PM10+N02: 0.24 (-0.49, 0.97) 0-1
    PM10+S02:0.45 (-0.27, 1.17)0-1
    PM,o+03: 0.72 (0.00,  1.44)0-1
    High:
    All ages: 2.20 (0.74, 3.68) 0-1
    <65: 2.34 (-0.09, 4.83) 0-1
    > 65: 2.14 (0.42, 3.89)0-1
    PM,o+N02:1.87 (0.42, 3.35)0-1
    PM,o+S02: 2.12 (0.67, 3.60)0-1
    PM10+03: 2.15 (0.55,  3.77)0-1
    
    Cardiovascular:
    Normal:
    All ages: 0.39 (0.11, 0.66) 0-1
    <65: 0.17 (-0.40, 0.73)0-1
    > 65: 0.44 (0.14, 0.74)0-1
    PMio+N02:0.11  (-0.23,0.45)0-1
    PM,o+S02: 0.27 (-0.02, 0.55) 0-1
    PM10+03: 0.42 (0.15,  0.70)
    Low:
    All ages: 0.72 (-0.25,1.70)0-1
    <65: 2.63 (0.67, 4.63) 0-1
    > 65: 0.24 (-0.84, 1.32)0-1
    PM,o+N02: 0.37 (-0.62, 1.38)0-1
    PM10+S02:0.50 (-0.47, 1.49)0-1
    PM10+03: 0.82 (-0.16, 1.80)0-1
    High:
    All ages: 3.28 (1.24, 5.37)0-1
    <65: 4.32 (0.10, 8.71)0-1
    > 65: 3.03 (0.77, 5.34) 0-1
    PM10+N02: 3.00 (0.95, 5.09) 0-1
    PM10+S02: 3.20 (1.16, 5.29)0-1
    PMio+03:3.71 (1.50,5.96)0-1
    
    Stroke:
    Normal:
    All ages: 0.38 (0.06, 0.70)
    <65: 0.17 (-0.53, 0.88)0-1
    > 65: 0.43 (0.07, 0.79) 0-1
    PM10+N02: 0.09 (-0.31, 0.49) 0-1
    PM10+S02:0.31  (-0.03, 0.64) 0-1
    PM,o+03: 0.38 (0.05,  0.71) 0-1
    Low:
    All ages: 0.67 (-0.50,1.85)0-1
    <65: 2.85 (0.34, 5.42) 0-1
    > 65: 0.11 (-1.22, 1.45)0-1
    PM,o+N02: 0.29 (-0.90, 1.51)0-1
    PMio+S02:0.53 (-0.65, 1.73)0-1
    December 2009
                                    E-315
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                 PM10+03: 0.69 (-0.48, 1.87)0-1
                                                                                                                 High:
                                                                                                                 All ages: 2.35 (-0.03, 4.78) 0-1
                                                                                                                 <65: 4.54 (-0.79, 10.16)0-1
                                                                                                                 > 65:1.83 (-0.83, 4.57)
                                                                                                                 PM10+N02: 2.05 (-0.34, 4.49) 0-1
                                                                                                                 PM10+S02:2.31 (-0.07, 4.74) 0-1
                                                                                                                 PM,o+03: 2.77 (0.25, 5.35) 0-1
    
                                                                                                                 Cardiac:
                                                                                                                 Normal:
                                                                                                                 All ages: 0.32 (-0.14, 0.79)0-1
                                                                                                                 <65:-0.04 (-1.07, 1.01)0-1
                                                                                                                 > 65: 0.40 (-0.10,0.91)0-1
                                                                                                                 PM10+N02: 0.02 (-0.57, 0.60) 0-1
                                                                                                                 PM10+S02:0.11 (-0.38,0.61)0-1
                                                                                                                 PM,o+03: 0.41 (-0.06, 0.89) 0-1
                                                                                                                 Low:
                                                                                                                 All ages: 0.50 (-1.10, 2.13)0-1
                                                                                                                 <65:1.79 (-1.65, 5.35)0-1
                                                                                                                 > 65: 0.19 (-1.55, 1.95)0-1
                                                                                                                 PM,o+N02: 0.12 (-1.53, 1.80)0-1
                                                                                                                 PM,o+S02:0.14 (-1.48, 1.78)0-1
                                                                                                                 PM10+03: 0.72 (-0.90, 2.37) 0-1
                                                                                                                 High:
                                                                                                                 All ages: 3.31 (-0.22, 6.97) 0-1
                                                                                                                 <65: 2.71 (-4.58, 10.56)0-1
                                                                                                                 > 65: 3.45 (-0.41, 7.46) 0-1
                                                                                                                 PM,o+N02: 3.01 (-0.54, 6.69) 0-1
                                                                                                                 PM10+S02:3.17 (-0.37, 6.84)0-1
                                                                                                                 PM10+03: 4.92 (0.96, 9.03) 0-1
    
                                                                                                                 Respiratory:
                                                                                                                 Normal:
                                                                                                                 All ages: 0.80 (0.25,1.35)0-1
                                                                                                                 <65:-0.35 (-1.85, 1.18)0-1
                                                                                                                 > 65: 0.93 (0.38, 1.50)0-1
                                                                                                                 PM,o+N02: 0.30 (-0.39, 0.99) 0-1
                                                                                                                 PM10+S02: 0.64 (0.07, 1.22)0-1
                                                                                                                 PM10+03: 0.84 (0.28, 1.41)0-1
                                                                                                                 Low:
                                                                                                                 All ages: 1.07 (-0.76, 2.95)0-1
                                                                                                                 <65:-1.13 (-6.33, 4.35)0-1
                                                                                                                 > 65:1.30 (-0.57, 3.20)0-1
                                                                                                                 PM10+N02: 0.44 (-1.46, 2.36)0-1
                                                                                                                 PM10+S02:0.80 (-1.05, 2.69)0-1
                                                                                                                 PMio+03:1.11  (-0.73,2.99)0-1
                                                                                                                 High:
                                                                                                                 All ages: 1.15 (-3.54, 6.07)0-1
                                                                                                                 <65:-3.42 (-15.82,  10.80)0-1
                                                                                                                 > 65:1.76 (-3.03, 6.78)0-1
                                                                                                                 PM,o+N02: 0.63 (-4.07, 5.55) 0-1
                                                                                                                 PM,o+S02:1.03 (-3.66, 5.94)0-1
                                                                                                                 PM10+03: 2.66 (-2.44, 8.02) 0-1
    
                                                                                                                 Cardiopulmonary:
                                                                                                                 Normal:
                                                                                                                 All ages: 0.45 (0.19, 0.70)0-1
                                                                                                                 <65: 0.07 (-0.47, 0.61)0-1
                                                                                                                 > 65: 0.53 (0.25, 0.81)0-1
                                                                                                                 PM,o+N02: 0.15 (-0.17, 0.47)0-1
                                                                                                                 PM,o+S02: 0.34 (0.07, 0.61)0-1
                                                                                                                 PM10+03: 0.43 (0.17, 0.70)0-1
                                                                                                                 Low:
                                                                                                                 All ages: 0.69 (-0.22,1.61)0-1
                                                                                                                 <65:1.95 (0.04, 3.90)0-1
                                                                                                                 > 65: 0.43 (-0.57, 1.44)0-1
                                                                                                                 PM,o+N02: 0.33 (-0.61, 1.27)0-1
                                                                                                                 PM10+S02:0.50 (-0.42, 1.43)0-1
                                                                                                                 PM10+03: 0.76 (-0.16, 1.68)0-1
                                                                                                                 High:
                                                                                                                 All ages: 3.02 (1.03, 5.04)0-1
                                                                                                                 <65: 3.49 (-0.66, 7.81)0-1
                                                                                                                 > 65: 2.91  (0.74,5.12)0-1
                                                                                                                 PM10+N02: 2.70 (0.72, 4.73) 0-1
                                                                                                                 PM10+S02: 2.95 (0.96, 4.97) 0-1
                 	PMio+03: 3.32 (1.16, 5.53)0-1
    December 2009                                                     E-316
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Ren et al. (2006, 0928241
    
    Period of Study: Jan 1996-Dec 2001
    
    Location: Brisbane, Australia
    Outcome: Mortality:
    
    Nonaccidental
    Cardiovascular (390-448)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    cubic spline
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 15.84
    
    Range (Min, Max): (2.5, 60)
    
    Copollutant: 0;
    The study presents quantitative results
    associated with an incremental increase
    in temperature, notPM10.
    Reference: Roberts (2004, 0879241
    
    Period of Study: 1987-1994
    
    Location: Cook County, Illinois
    
    Allegheny County, Pennsylvania
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    smooth splines
    
    Poisson GLM, natural cubic splines
    
    Age Groups: > 65 yr
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    Median (SD) unit:
    Cook County
    Lower Temp.: 29.24
    Middle Temp.: 30.03
    Upper Temp.: 52.76
    Allegheny County
    Lower Temp.: 16.50
    Middle Temp.: 24.97
    Upper Temp.: 55.42
    Range (10th, 90th):
    Cook County
    Lower Tern.: (16.42, 46.42)
    Middle Temp.: (14.79, 56.33)
    Upper Temp.: (30.81, 82.81)
    Allegheny County
    Lower Temp.: (5.14, 34.54)
    Middle Temp.: (8.91, 57.91)
    Upper Temp.: (30.91, 88.99)
    Increment: 10|jg/m
    
    % Increase (SE) lag:
    
    GLM
    Cook
    a = 0.5
    No Interaction: 0.288% (0.157)0
    Low Temp.:-0.272% (0.380)0
    Middle Temp.: 0.344% (0.165)0
    Upper Temp.: 0.281% (0.239)0
    No Interaction: 0.359% (0.149)1
    Low Tern p.:-0.168% (0.372)1
    Middle Temp.: 0.361% (0.156)1
    Upper Temp.: 0.616% (0.250)1
    No Interaction: 0.465% (0.176) 0-1 ma
    Low Temp.: 0.043% (0.397) 0-1 ma
    Middle Temp.: 0.506% (0.184) 0-1 ma
    Upper Temp.: 0.464% (0.256) 0-1 ma
    No Interaction: 0.633% (0.214) 0-3 ma
    Low Temp.: 0.365% (0.419) 0-3 ma
    Middle Temp.: 0.638% (0.222) 0-3 ma
    Upper Temp.: 0.718% (0.295) 0-3 ma
    a=1
    No Interaction: 0.117% (0.157)0
    Low Tern p.:-0.351% (0.406)0
    Middle Temp.: 0.161% (0.165)0
    Upper Temp.: 0.096% (0.264)0
    No Interaction: 0.141% (0.150)1
    Low Tern p.:-0.366% (0.397)1
    Middle Temp.: 0.161% (0.156)1
    Upper Temp.: 0.301% (0.278)1
    No Interaction: 0.260% (0.181) 0-1 ma
    Low Temp.: -0.163% (0.431) 0-1 ma
    Middle Temp.: 0.305% (0.188) 0-1 ma
    Upper Temp.: 0.207% (0.291) 0-1 ma
    No Interaction: 0.289% (0.225) 0-3 ma
    Low Temp.: 0.014% (0.459) 0-3 ma
    Middle Temp.: 0.311% (0.231) 0-3 ma
    Upper Temp.: 0.301% (0.334) 0-3 ma
    a = 2
    No Interaction: 0.060% (0.158)
    0
    0
    Low Tern p.:-0.464% (0.486)
    0
    0
    Middle Temp.: 0.115% (0.168)
    0
    0
    Upper Temp.:-0.022% (0.319)
    0
    0
    No Interaction: 0.101% (0.152)1
    Low Temp.:-0.432% (0.484)1
    Middle Temp.: 0.089% (0.160)1
    Upper Temp.: 0.455% (0.327)1
    No Interaction: 0.129% (0.184) 0-1 ma
    Low Temp.: -0.320% (0.546) 0-1 ma
    Middle Temp.: 0.157% (0.193) 0-1 ma
    Upper Temp.: 0.130% (0.346) 0-1 ma
    No Interaction: 0.090% (0.236) 0-3 ma
    Low Temp.: -0.319% (0.572) 0-3 ma
    Middle Temp.: 0.105% (0.244)
    0-3 ma
    Upper Temp.: 0.193% (0.412)
    0-3 ma
    December 2009
                                   E-317
    

    -------
                 Study                       Design & Methods                Concentrations1             Effect Estimates (95% Cl)
    
    
                                                                                                            Allegheny
                                                                                                            a = 0.5
                                                                                                            No Interaction: 0.078% (0.209) 0
                                                                                                            Low Tern p.:-0.759% (0.643)0
                                                                                                            Middle Temp.: 0.207% (0.216)0
                                                                                                            High Temp.:-0.367% (0.364)0
                                                                                                            No Interaction: 0.189% (0.206)1
                                                                                                            Low Temp.:-0.335% (0.691)1
                                                                                                            Middle Temp.: 0.293% (0.215)1
                                                                                                            High Temp.:-0.171% (0.349)1
                                                                                                            No Interaction: 0.224% (0.246) 0-1 ma
                                                                                                            Low Temp.:-0.753% (0.763) 0-1 ma
                                                                                                            Middle Temp.: 0.353% (0.253) 0-1 ma
                                                                                                            High Temp.: -0.142% (0.382) 0-1  ma
                                                                                                            No Interaction: 0.526% (0.300) 0-3 ma
                                                                                                            Low Temp.: 0.050% (0.733) 0-3 ma
                                                                                                            Middle Temp.: 0.688% (0.310) 0-3 ma
                                                                                                            High Temp.: -0.043% (0.436) 0-3 ma
    
                                                                                                            a=1
                                                                                                            No Interaction: 0.078% (0.211)0
                                                                                                            Low Tern p.:-0.694% (0.656)0
                                                                                                            Middle Temp.: 0.214% (0.219)0
                                                                                                            High Temp.:-0.533% (0.430)0
                                                                                                            No Interaction: 0.179% (0.207)1
                                                                                                            Low Temp.:-0.283% (0.718)1
                                                                                                            Middle Temp.: 0.273% (0.217)1
                                                                                                            High Temp.:-0.221% (0.396)1
                                                                                                            No Interaction: 0.221% (0.249) 0-1 ma
                                                                                                            Low Temp.: -0.731% (0.794) 0-1 ma
                                                                                                            Middle Temp.: 0.348% (0.258) 0-1 ma
                                                                                                            High Temp.: -0.253% (0.447) 0-1  ma
                                                                                                            No Interaction: 0.464% (0.309) 0-3 ma
                                                                                                            Low Temp.: 0.056% (0.780) 0-3 ma
                                                                                                            Middle Temp.: 0.626% (0.319) 0-3 ma
                                                                                                            High Temp.: -0.356% (0.516) 0-3 ma
    
                                                                                                            a = 2
                                                                                                            No Interaction: 0.034% (0.217)0
                                                                                                            Low Temp.:-1.059% (0.715)0
                                                                                                            Middle Temp.: 0.162% (0.230)0
                                                                                                            High Temp.:-0.233% (0.489)0
                                                                                                            No Interaction: 0.130% (0.214)1
                                                                                                            Low Tern p.:-0.189% (0.800)1
                                                                                                            Middle Temp.: 0.157% (0.226)1
                                                                                                            High Temp.: 0.070% (0.471)1
                                                                                                            No Interaction: 0.183% (0.260) 0-1 ma
                                                                                                            Low Temp.: -0.918% (0.907) 0-1 ma
                                                                                                            Middle Temp.: 0.279% (0.273) 0-1 ma
                                                                                                            High Temp.: -0.001% (0.526) 0-1  ma
                                                                                                            No Interaction: 0.270% (0.331) 0-3 ma
                                                                                                            Low Tern p.: -0.105% (0.898) 0-3 ma
                                                                                                            Middle Temp.: 0.394% (0.346) 0-3 ma
                                                                                                            High Temp.: -0.287% (0.615) 0-3 ma
                                                                                                            GAM
                                                                                                            Cook
                                                                                                            a = 0.5
                                                                                                            No Interaction: 0.438% (0.151)0
                                                                                                            Low Tern p.:-0.178% (0.364)0
                                                                                                            Middle Temp.: 0.439% (0.163)0
                                                                                                            Upper Temp.: 0.627% (0.197)0
                                                                                                            No Interaction: 0.495% (0.144)1
                                                                                                            Low Temp.:-0.114% (0.361)1
                                                                                                            Middle Temp.: 0.460% (0.151)1
                                                                                                            Upper Temp.: 0.938% (0.208)1
                                                                                                            No Interaction: 0.710% (0.169) 0-1 ma
                                                                                                            Low Temp.: 0.151% (0.379) 0-1 ma
                                                                                                            Middle Temp.: 0.686% (0.180) 0-1 ma
                                                                                                            Upper Temp.: 0.952% (0.214) 0-1 ma
                                                                                                            No Interaction: 0.923% (0.203) 0-3 ma
                                                                                                            Low Temp.: 0.532% (0.402) 0-3 ma
                                                                                                            Middle Temp.: 0.855% (0.210) 0-3 ma
                                                                                                            Upper Temp.: 1.289% (0.251) 0-3 ma
    
                                                                                                            a=1
                	No Interaction: 0.190% (0.154)0
    December 2009                                                  E-318
    

    -------
                 Study                       Design & Methods                Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                            Low Tern p.:-0.338% (0.414)0
                                                                                                            Middle Temp.: 0.242% (0.162)0
                                                                                                            Upper Temp.: 0.161% (0.230)0
                                                                                                            No Interaction: 0.239% (0.146)1
                                                                                                            Low Tern p.:-0.283% (0.406)1
                                                                                                            Middle Temp.: 0.248% (0.152)1
                                                                                                            Upper Temp.: 0.453% (0.244)1
                                                                                                            No Interaction: 0.353% (0.174) 0-1 ma
                                                                                                            Low Temp.: -0.074% (0.437) 0-1 ma
                                                                                                            Middle Temp.: 0.388% (0.182) 0-1 ma
                                                                                                            Upper Temp.: 0.345% (0.251) 0-1 ma
                                                                                                            No Interaction: 0.453% (0.213) 0-3 ma
                                                                                                            Low Temp.: 0.190% (0.460) 0-3 ma
                                                                                                            Middle Temp.: 0.455% (0.219) 0-3 ma
                                                                                                            Upper Temp.: 0.557% (0.294) 0-3 ma
    
                                                                                                            a = 2
                                                                                                            No Interaction: 0.071% (0.157)
                                                                                                            0
                                                                                                            0
                                                                                                            Low Tern p.:-0.534% (0.478)
                                                                                                            0
                                                                                                            0
                                                                                                            Middle Temp.: 0.132% (0.165)
                                                                                                            0
                                                                                                            0
                                                                                                            Upper Temp.: 0.011% (0.264)
                                                                                                            0
                                                                                                            0
                                                                                                            No Interaction: 0.099% (0.150)1
                                                                                                            Low Temp.:-0.467% (0.472)1
                                                                                                            Middle Temp.: 0.109% (0.156)1
                                                                                                            Upper Temp.: 0.329% (0.278)1
                                                                                                            No Interaction: 0.168% (0.180) 0-1 ma
                                                                                                            Low Temp.: -0.371% (0.525) 0-1 ma
                                                                                                            Middle Temp.: 0.216% (0.188) 0-1 ma
                                                                                                            Upper Temp.: 0.116% (0.290) 0-1 ma
                                                                                                            No Interaction: 0.149% (0.227) 0-3 ma
                                                                                                            Low Temp.: -0.291% (0.557) 0-3 ma
                                                                                                            Middle Temp.: 0.174% (0.233) 0-3 ma
                                                                                                            Upper Temp.: 0.210% (0.340) 0-3 ma
    
                                                                                                            Allegheny
                                                                                                            a = 0.5
                                                                                                            No Interaction: 0.245% (0.203) 0
                                                                                                            Low Temp.:-0.727% (0.648)0
                                                                                                            Middle Temp.: 0.314% (0.216)0
                                                                                                            High Temp.: 0.308% (0.287)0
                                                                                                            No Interaction: 0.446% (0.199)1
                                                                                                            Low Temp.:-0.307% (0.701)1
                                                                                                            Middle Temp.: 0.469% (0.211)1
                                                                                                            High Temp.: 0.556% (0.285)1
                                                                                                            No Interaction: 0.522% (0.237) 0-1 ma
                                                                                                            Low Temp.: -0.646% (0.761) 0-1 ma
                                                                                                            Middle Temp.: 0.567% (0.251) 0-1 ma
                                                                                                            High Temp.: 0.640% (0.307) 0-1 ma
                                                                                                            No Interaction: 0.977% (0.282) 0-3 ma
                                                                                                            Low Temp.: 0.307% (0.733) 0-3 ma
                                                                                                            Middle Temp.: 1.027% (0.296) 0-3 ma
                                                                                                            High Temp.: 1.001% (0.352) 0-3 ma
                                                                                                            a=1
                                                                                                            No Interaction: 0.107% (0.209)0
                                                                                                            Low Temp.:-0.819% (0.699)0
                                                                                                            Middle Temp.: 0.229% (0.219)0
                                                                                                            High Temp.:-0.214% (0.350)0
                                                                                                            No Interaction: 0.223% (0.205) 1
                                                                                                            Low Temp.:-0.316% (0.751)1
                                                                                                            Middle Temp.: 0.295% (0.216)1
                                                                                                            High Temp.: 0.002% (0.341)1
                                                                                                            No Interaction: 0.267% (0.246) 0-1 ma
                                                                                                            Low Temp.: -0.797% (0.840) 0-1 ma
                                                                                                            Middle Temp.: 0.372% (0.257) 0-1 ma
                                                                                                            High Temp.: 0.035% (0.372) 0-1 ma
                                                                                                            No Interaction: 0.534% (0.302) 0-3 ma
                                                                                                            Low Temp.: 0.029% (0.810) 0-3 ma
                                                                                                            Middle Temp.: 0.660% (0.314) 0-3 ma
                                                                                                            High Temp.: 0.071% (0.431) 0-3 ma
    December 2009                                                  E-319
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                                                             a = 2
                                                                                                             No Interaction: 0.061% (0.214)0
                                                                                                             Low Temp.:-1.048% (0.749)0
                                                                                                             Middle Temp.: 0.206% (0.226)0
                                                                                                             High Temp.:-0.332% (0.419)0
                                                                                                             No Interaction: 0.145% (0.211)1
                                                                                                             Low Tern p.:-0.278% (0.816)1
                                                                                                             Middle Temp.: 0.210% (0.223)1
                                                                                                             High Temp.:-0.105% (0.394)1
                                                                                                             No Interaction: 0.180% (0.256) 0-1 ma
                                                                                                             Low Temp.: -1.028% (0.931) 0-1 ma
                                                                                                             Middle Temp.: 0.298% (0.269) 0-1 ma
                                                                                                             High Temp.:-0.114% (0.441) 0-1 ma
                                                                                                             No Interaction: 0.275% (0.324) 0-3 ma
                                                                                                             Low Tern p.: -0.384% (0.915) 0-3 ma
                                                                                                             Middle Temp.: 0.436% (0.338) 0-3 ma
                                                                                                             High Temp.: -0.366% (0.513) 0-3 ma
    Reference: Roberts (2004, 0879241
    
    Period of Study: 1987-1994
    
    Location: Cook County, Illinois
    
    Allegheny County, Pennsylvania
    Outcome: Mortality:
    
    Nonaccidental
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GLM
    
    Age Groups: 2 65 yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max):
    
    Max = 89
    The study does not present quantitative
    results.
    Reference: Roberts (Roberts, 2005,
    0879921
    Period of Study:
    Cook County: 1987-2000.
    Allegheny County: 1987-1998
    
    Location: Cook County, Illinois
    
    Allegheny County, Pennsylvania
    Outcome: Mortality:
    
    Nonaccidental
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    
    Age Groups: 2 65 yr
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: NR
    p(SE)lag:
    Standard Model
    Cook County
    0.000127(0.000264)  0
    -0.000042 (0.000249) 1
    -0.000441 (0.000246) 2
    
    Allegheny County
                                                                                                             0.000693
                                                                                                             0.000356
                                                                                   0.000437) 0
                                                                                   0.000423) 1
                                                                                                             0.000524(0.000415)2
    
                                                                                                             Moving Total Model
                                                                                                             Cook County
                                                                                                             0.000150 (0.000187) k= 2
                                                                                                             -0.000047 (0.000153) k = 3
                                                                                                             0.000009 (0.000133) k= 4
    
                                                                                                             Allegheny County
                                                                                                             0.000633 (0.000310) k= 2
    0.000542
    0.000598
    0.000255) k= 3
    0.000351) k= 4
    Reference: Roberts (2006, 0897621     Outcome: Mortality:
    Period of Study: 1987-2000
    
    Location: Cook County, Illinois
    
    Suffolk County,  Massachusetts
    (NMMAPS)
    Nonaccidental
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GLM
    
    Age Groups: > 65 yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Cook County: 33.7 (19.4)
    Suffolk County: 25.9 (11.8)
    Range (10th, 90th):
    Cook County: (13.4,  58.1)
    Suffolk County: (14.0, 41.7)
    Copollutant (correlation):
    Cook County
    CO: r = 0.30
    N02:r = 0.53
    S02:r = 0.45
    03:r = 0.44
    
    Suffolk County
    CO: r = 0.33
    N02:r = 0.43
    S02:r = 0.23
    03:r = 0.36	
    Increment:
    
    Cook County: 19.4 pg/m3
    
    Suffolk County:  14.0|jg/m3
    
    % Increase (SD)  lag:
    Cook County
    Standard Model: 0.49% (0.25) 0
    Proposed Model: 0.29% (0.16)0
    Standard Model: 0.67% (0.25) 0-2 avg
    Proposed Model: 0.49% (0.25) 0-2 avg
    
    Suffolk County
    Standard Model: 0.88% (1.27)0
    Proposed Model: 0.85% (0.84) 0
    Standard Model: 1.60% (0.71) 0-2 avg
    Proposed Model: 1.35% (0.73) 0-2 avg
    December 2009
                                    E-320
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Roberts and Martin (2006,
    0977991
    
    Period of Study: 1987-2000
    
    Location: Cook County, Illinois
    (NMMAPS)
    Outcome: Mortality: Nonaccidental
    
    Study Design: Time-series
    
    Statistical Analyses: Dose-response
    
    1. Piecewise linear relationship (no-
    threshold) with change point at
    25 pg/m  and 50 pg/m
    
    2. Piecewise linear relationship
    (threshold), exposure below 25 pg/m3
    no effect  and exposures above
    50 pg/m  having a different effect then
    exposures between 25 pg/m3 and
    50 pg/m3
    
    Age Groups: > 65 yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    IQR (26th, 76th):
    
    (23.9, 45.4)
    
    Suffolk County: (14.0, 41.7)
    
    Copollutant (correlation): NR
    The study does not present quantitative
    results.
    Reference: Roberts and Martin (2006,
    0886701
    Period of Study: 1987-2000
    
    Location: 109 U.S. cities (NMMAPS)
    Outcome: Mortality: Nonaccidental
    
    Cardiorespiratory
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    
    2-stage Bayesian hierarchical model
    
    Age Groups: All ages
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    IQR (26th, 76th): NR
    
    Copollutant (correlation): NR
    Increment: NR
    
    P x 1000 (SEx 1000)  lag:
    Nonaccidental
    Model 1
    Base df: 0.079 (0.050) 0
    Double df: 0.044 (0.046)0
    Half df: 0.107 (0.052)0
    Base df: 0.180 (0.044)1
    Double df: 0.149 (0.047)1
    Half df: 0.254 (0.048)1
    Base df: 0.059 (0.056) 2
    Double df: 0.024 (0.056) 2
    Half df: 0.143 (0.054) 2
    
    Model 2
    Base df: 0.115 (0.037) 0-2 ma
    Double df: 0.107 (0.034) 0-2 ma
    Half df: 0.145 (0.039) 0-2 ma
    
    Cardio-respiratory
    Model 1
    Base df: 0.103 (0.068)0
    Double df: 0.056 (0.067)0
    Half df: 0.134 (0.066)0
    Base df: 0.232 (0.060) 1
    Double df: 0.179 (0.067)1
    Half df: 0.309 (0.059)1
    Base df: 0.210 (0.078) 2
    Double df: 0.144 (0.075) 2
    Half df: 0.305 (0.079) 2
    
    Model 2
    Base df: 0.168 (0.047) 0-2 ma
    Double df: 0.140 (0.044) 0-2 ma
    Half df: 0.196 (0.051) 0-2 ma
    Notes: Model 1 uses current day's
    mortality count, while Model 2 uses a 3-
    day moving total mortality count.
    December 2009
                                    E-321
    

    -------
                  Study
                                               Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Roberts and Martin (2007,   Outcome: Mortality: Total
                                       (nonaccidental)
    156917'
    
    Period of Study: 1987-2000
    
    Location: 8 U.S. cities and >100 U.S.
    cities (NM MAPS)
                                       Cardiorespiratory
    
                                       Study Design: Time-series
    
                                       Statistical Analyses: Poisson
    
                                       Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    Increment: 10|jg/m
    
    P x 1000 (SEx 1000) lag:
    8 U.S. cities
    Distributed Lag Model: 0.229
    0-2
    Weighted Model: 0.315
    0-2
    Standard Model:
    0.276
    0
    -0.062
    1
    0.476
    2
    
    90 U.S. cities
    Total (nonaccidental)
    Standard Model:
    0.078 (0.039)
    0
    0.182(0.037)
    1
    0.108(0.036)
    2
    Moving Total Model: 0.131 (0.023)
    0-2
    Weighted Model: 0.274 (0.075)
    0-2
    
    Cardio-respiratory
    Standard Model:
    0.096 (0.055)
    0
    0.232 (0.053)
    1
    0.226(0.051)
    2
    Moving Total Model:
    0.174(0.032)
    0-2
    Weighted Model:
    0.389(0.105)
    0-2
    Notes: The 8 U.S. cities consist of
    Chicago, Cleveland, Denver, El Paso,
    Houston, Nashville, Pittsburgh, and Salt
    Lake City.
    December 2009
                                                                       E-322
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Roberts and Martin (2007,
    1569161
    
    Period of Study: 1987-2000
    
    Location: 10 U.S. cities (NMMAPS)
    Outcome: Mortality: Nonaccidental
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    
    Age Groups: > 65 yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Anchorage: 27.32
    Chicago: 36.95
    Cleveland: 39.83
    Detroit: 40.78
    El Paso: 40.14
    Minneapolis/a. Paul: 28.01
    Pittsburgh: 35.09
    Salt Lake City: 37.40
    Seattle: 28.72
    Spokane: 34.52
    Range (Min, Max): NR
    Increment: NR
    
    P Coefficient (SE) lag:
    
    Pooled Estimates
    
    Combined Model (Unconstrained
    Distributed Lag Model + Piecewise
    Linear Dose-Response Function)
    Change-point: 60 pg/m3
    Slope below: 0.00130 (0.00016)
    0-5
    Slope above:-0.00163 (0.00026)
    0-5
    Change-point: 30 pg/m
    Slope below: 0.00014 (0.00039)
    0-5
    Slope above:-0.00003 (0.00015)
    0-5
    Piecewise Linear Dose-Response
    Model
    Change-point: 60 pg/m3
    Slope below: 0.00044 (0.00011)
    3-day ma
    Slope above:-0.00077 (0.00020)
    3- day ma
    Change-point: 30 pg/m3
    Slope below: 0.00022 (0.00026)
    3-day ma
    Slope above:-0.00004 (0.00011)
    3-day ma
    Polynomial Distributed Lag Model
    (degree 2)
    0.00046(0.00011)
    0-5
    Reference: Samoli et al. (2005,
    0874361
    
    Period of Study: 1990-1997
    
    Location: 22 European cities (APHEA-
    2)
    Outcome: Mortality:
    All-cause (nonaccidental) (<800)
    Cardiovascular (390-459)
    Respiratory (460-519)
    Study Design: Time-series
    
    Statistical Analyses: Hierarchical
    modeling:
    
    1. Poisson GAM, penalized splines
    
    2. Multivariate modeling
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Median (SD) unit:
    
    Range: (Stockholm: 14 pg/m3 to Torino:
    65 |jg/ms)
    
    Percentile (90th):
    
    Range: (Stockholm: 27 pg/m3 to Torino:
    129 pg/m3)
    The study does not present quantitative
    results.
    «ge oroup*. «,, dya, Copollutant (correlation): BS
    Reference: Schwartz (2004, 0789981
    Period of Study: 1986-1993
    Location: 14 U.S. cities
    
    
    
    Outcome: Mortality:
    Nonaccidental (<800)
    Study Design: Case-crossover
    Time-series
    Statistical Analyses: Conditional
    logistic regression
    Poisson
    Age Groups: All ages
    Notes: Case days matched to referent
    days that had the same temperature.
    
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (Min, Max): NR
    Copollutant (correlation): NR
    
    
    Increment: 10 pg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    Overall:
    Two stage: 0.36% (0.22, 0.50)1
    Single stage: 0.33% (0.19, 0.46)1
    More winter temperature lags:
    Two Stage: 0.39% (0.23, 0.56)1
    One stage: 0.32% (0.19, 0.46)1
    Time stratified with temperature
    matching:
    Two Stage: 0.39% (0.19, 0.58)1
    One Stage: 0.53% (0.34, 0.72) 1
    Poisson regression:
    0.40% (0.18, 0.62)1
    December 2009
                                    E-323
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Schwartz (2004, 0535061
    Period of Study: 1986-1993
    Location: 14 U.S. cities
    Outcome: Mortality:
    Nonaccidental (<800)
    Study Design: Case-crossover
    Statistical Analyses: Time-stratified
    conditional logistic regression
    Age Groups: All ages
    Notes: Case days matched to referent
    days based on concentration of
    gaseous air pollutants. Matched on the
    following conditions:
    1. 24-h avg S02 within 1 ppb
    2. Daily-maximum 0? within 2 ppb
    3. 24-h avg N02 within 1 ppb
    4. 24-h avg CO within 0.03 ppm
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Median (SD) unit: Range: 23-36 pg/m3
    IQR (25th, 75th):
    Range 25th: 17-24 pg/m3
    Range 75th: 31-57 pg/m3
    Copollutant (correlation): CO
    S02
    N02
    03
    Increment: 10|jg/m
    P x 1000 (SEx 1000) lag:
    Matched on CO: 0.527 (0.251)
    0-1 avg
    Matched on 03: 0.451 (0.170)
    0-1 avg
    Matched on N02: 0.784 (0.185)
    0-1 avg
    Matched on S02: 0.811 (0.175)
    0-1 avg
    Reference: Sharovsky et al. (2004,
    1569761
    Period of Study: Jul 1996-Jun 1998
    Location: Sao Paulo, Brazil
    Outcome: Mortality:
    Myocardial infarction
    Study Design: Time-series
    Statistical Analyses: Poisson GAM
    Age Groups: 2 35 yr
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD): 58.2 (25.8)
    Range (Min, Max): (23,186)
    Copollutant (correlation):
    CO: r = 0.73
    S02:r = 0.72
    Increment: 10|jg/m
    p(SE)lag:
    PM10: 0.001 (0.001)
    PMio+CO+S02: 0.0004 (0.0008)
    Reference: Simpson et al. (2005,
    0874381
    
    Period of Study: 1/1996-12/1999
    Location: 4 Australian cities
    
    
    
    
    
    
    
    
    
    Reference: Slaughter et al. (2005,
    0738541
    
    Period of Study: Jan 1995-Dec 1999
    Location: Spokane, Washington
    
    
    
    Reference: Staniswalis et al. (2005,
    0874731
    
    Period of Study: 1992-1995
    Location: El Paso, Texas
    
    
    
    
    
    
    
    Reference: Stafoggia et al. (2008,
    1570051
    
    Period of Study: 1997-2004
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Cardiovascular (390-459)
    Respiratory (460-51 9)
    
    Study Design: Time-series
    meta-analysis
    Statistical Analyses: Poisson GAM,
    natural splines
    Poisson GLM, natural splines
    
    Age Groups: All ages
    
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Study Design: Time-series
    Statistical Analyses: Poisson GLM,
    natural splines
    Age Groups: All ages
    
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    Principal component analysis (PCA)
    Age Groups: All ages
    
    
    
    
    Outcome:
    
    Mortality:
    Total (nonaccidental) (<800)
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Brisbane: 16.60
    Sydney: 16.30
    Melbourne: 18.20
    
    Range (Min, Max):
    Brisbane: (2.6, 57.6)
    Sydney: (3.7, 75.5)
    Melbourne: (3.3, 51.9)
    Copollutant:
    PM25
    CO
    N02
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (9th, 95th): (7.9, 41.9) pg/m3
    Copollutant (correlation):
    DM
    PMio
    PM10.25:r = 0.94
    CO: r = 0.32
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD): NR
    
    Range (Min, Max):
    (0.2, 133.4)
    Notes: The chemical composition and
    size distribution of PM was not
    available, therefore, the study used
    wind speed as a surrogate variable for
    the PMio composition.
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD) unit:
    Bologna: 50.4 (31. 7)
    Increment: 10|jg/m3
    
    % Increase (Lower Cl, Upper Cl)
    lag:
    0.2% (-0.8, 1.2)
    
    
    
    
    
    
    
    
    Increment: : 25 pg/m3
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    1.00(0.97,1.03) 1
    0.98(0.95, 1.01) 2
    1.00(0.97, 1.03) 3
    
    Increment: 10|jg/m3
    
    % Increase (Lower Cl, Upper Cl)
    lag:
    
    Poisson regression: 1.7% 3
    PCA:
    24-hly measurements: 2.06% 3
    
    Daily avg: 1.7% 3
    
    
    Increment: 10|jg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    Cardiovascular
    All yr: 0.63% (0.31, 1.38) 0-1
    December 2009
                                   E-324
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
    Location: 9 Italian cities
                                         Cardiovascular (390-459)
    
                                         Respiratory (460-519)
    
                                         Other natural causes
    
                                         Study Design: Time-stratified case-
                                         crossover
    
                                         Statistical Analyses:
    
                                         Conditional logistic regression
    
                                         Age Groups: > 35 yr
                                 Florence: 37.5 (16.6)
                                 Mestre:48.1 (26.8)
                                 Milan: 57.9 (38.0)
                                 Palermo: 36.2 (21.7)
                                 Pisa: 35.1 (14.9)
                                 Rome: 47.3 (19.9)
                                 Taranto: 59.8 (18.9)
                                 Turin: 71.5 (38.1)
                                 Range (Min, Max): NR
    
                                 Copollutant (correlation): NR
                                Winter: 0.15% (-0.29, 0.59)0-1
                                Spring: 0.72% (-0.07,1.52)0-1
                                Summer: 2.90% (1.14, 4.69)0-1
                                Fall: 1.37% (0.43, 2.32)0-1
                                Apparent Temperature
                                <50th Percentile:
                                0.31% (-0.06, 0.67)0-1
                                50th-75th Percentile:
                                2.05% (0.47, 3.66) 0-1
                                >75th Percentile: 2.68% (1.20, 4.17) 0-1
    
                                Respiratory
                                All yr: 0.98% (0.27,  1.70)0-1
                                Winter: 0.41% (-0.67,1.51)0-1
                                Spring: 2.99% (1.18, 4.83)0-1
                                Summer: 3.89% (0.19, 7.73)0-1
                                Fall: 0.45% (-1.11, 2.03) 0-1
                                Apparent Temperature
                                <50th Percentile:
                                0.54% (-0.47, 1.57)0-1
                                50th-75th Percentile:
                                3.15% (0.64, 5.73)0-1
                                >75th Percentile:
                                4.12% (0.44, 7.93)0-1
    
                                Other natural causes
                                All yr: 0.37% (0.09,  0.66) 0-1
                                Wnter: 0.14% (-0.36, 0.63)0-1
                                Spring: 0.29% (-0.47,1.05)0-1
                                Summer: 2.15% (0.90, 3.42)0-1
                                Fall: 0.70% (-0.41, 1.83) 0-1
                                Apparent Temperature
                                <50th Percentile:
                                0.07% (-0.27, 0.41)0-1
                                50th-75th Percentile:
                                1.08% (-0.02, 2.19)0-1
                                >75th Percentile:
                                2.30% (1.06, 3.56)0-1
    
                                Total (nonaccidental)
                                All yr: 0.53% (0.25,  0.80) 0-1
                                Wnter: 0.20% (-0.08, 0.49) 0-1
                                Spring: 0.62% (0.14,1.10)0-1
                                Summer: 2.54% (1.31, 3.78) 0-1
                                Fall: 1.21% (0.37, 2.06)0-1
                                Apparent Temperature
                                <50th Percentile:
                                0.21% (-0.06, 0.47)0-1
                                50th-75th Percentile:
                                1.60% (0.64, 2.57)0-1
                                >75th Percentile:
                                2.55% (1.58, 3.52)0-1
    
                                P coefficient (SE) lag:
                                Linear interaction PM10 and Apparent
                                Temperature
                                Cardiovascular
                                <50th Percentile:
                                -0.000117(0.000415)0-1
                                50th-75th Percentile:
                                0.003445(0.001407)0-1
                                >75th Percentile:
                                0.002764(0.001795)0-1
    
                                Respiratory
                                <50th Percentile:
                                0.001119(0.000943)0-1
                                50th-75th Percentile:
                                -0.001120(0.003480)0-1
                                >75th Percentile:
                                0.005306 (0.004350) 0-1
    
                                Other natural causes
                                <50th Percentile:
                                0.000411(0.000383)0-1
                                50th-75th Percentile:
                                -0.001526(0.001207)0-1
                                >75th Percentile:
    December 2009
                              E-325
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                                                              0.002564(0.001958)0-1
    
                                                                                                              Total (nonaccidental)
                                                                                                              <50th Percentile:
                                                                                                              0.000246 (0.000269) 0-1
                                                                                                              50th-75th Percentile:
                                                                                                              0.000584 (0.000880) 0-1
                                                                                                              >75th Percentile:
                                                                                                              0.002396(0.001629)0-1
    Reference: Stolzel et al. (2007,
    0913741
    
    Period of Study: Sep 1995-Aug 2001
    
    Location: Erfurt, Germany
    Outcome:
    
    Mortality:
    
    Total (nonaccidental) (<800)
    
    Cardio-respiratory (390-459, 460-519,
    785, 786)
    
    Study Design: Time-series
    
    Statistical Analyses:
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD) unit:: 31.9 (23.2)
    
    IQR (25th, 75th):
    
     (16.5, 39.5)
    
    Copollutant (correlation):
    Increment: 23 pg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Total (nonaccidental)
    1.004(0.980
    1.029)
    0
    1.004(0.981
    1.027)
    1
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Sullivan et al. (2003,
    0431561
    Period of Study:
    1985-1994
    Location: Western Washington
    
    
    
    
    
    
    Poisson GAM
    
    Age Groups: All ages
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome:
    Out-of-hospital cardiac arrest
    Study Design: Case-crossover
    Statistical Analyses:
    Conditional logistic regression
    Age Groups: 19-79
    Study Population: Out-of-hospital
    cardiac arrests: 1,206
    
    
    
    
    IVIUJ. I-U.3. r = U.03
    MC0.01-2.5:r = 0.84
    NO: r = 0.54
    
    N02:r = 0.62
    CO: r = 0.50
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Median (SD) unit:
    Lag 0: 28.05
    Lag 1:27.97
    Lag 2: 28.40
    Range (Min, Max): (7.38, 89.83)
    Copollutant (correlation):
    S02
    CO
    Notes: Study used nephelometry to
    measure particles and equated the
    measurements to PM2 5 concentrations.
    0.998 (0.976
    1.021)
    2
    0.984 (0.962
    1 006)
    3
    0.993 (0.972
    1.015)
    4
    0.990 (0.969
    1.012)
    5
    Cardio-respiratory
    1.007 (0.981
    1.034)
    0
    1.006(0.981
    1.032)
    1
    0.996 (0.971
    1.021)
    2
    0.977 (0.953
    1.002)
    3
    0.994 (0.970
    1.018)
    4
    0.993 (0.969
    1.017)
    5
    Increment: : 16.51 pg/m3
    Odds Ratio (Lower Cl, Upper Cl) lag:
    Overall
    1.05(0.87, 1.27)
    0
    0.91 (0.75, 1.11)
    1
    1.03(0.82,1.28)
    9
    z
    
    December 2009
                                    E-326
    

    -------
    Study
    Reference: Sunyer et al. (2002,
    0348351
    
    Period of Study: 1985-1995
    Location: Barcelona, Spain
    
    
    
    
    
    
    
    Reference: Touloumi et al. (2005,
    0874771
    
    Period of Study: 1990-1997
    Location: 7 European cities (London,
    Budapest, Stockholm, Zurich, Paris,
    Lyon, Madrid) (APHEA2)
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Mortality:
    
    Respiratory mortality
    Study Design: Case-crossover
    
    Statistical Analyses: Condition logistic
    regression
    Age Groups: >14
    
    Study population: Asthmatic individuals:
    5,610
    
    
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    Cardiovascular (390-459)
    Study Design: Time-series
    Statistical Analyses: Poisson GAM,
    LOESS
    Age Groups: All ages
    
    
    
    
    
    
    
    
    
    Concentrations1
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Median (SD) unit: 61. 2
    
    Range (Mm, Max): (17.3, 240.7)
    Copollutant:
    BS
    N02
    03
    S02
    CO
    
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Median (SD) unit:
    London: 25.1
    Budapest: 40.2
    Stockholm: 13.7
    Zurich: 27.5
    Paris: 22.2
    Lyon: 38.5 p
    Madrid: 33.4
    IQR (25th, 75th):
    London: (20.3, 33.9)
    Budapest: (34.3, 45.8)
    Stockholm: (10.3, 19.1)
    Zurich: (19.2, 38.5)
    Paris: (16.0, 33.0)
    Lyon: (29.7, 50.4)
    Madrid: (27.6, 41.0)
    Copollutant (correlation): NR
    Effect Estimates (95% Cl)
    Increment: 32.7 pg/m3
    
    Odds Ratio (Lower Cl, Upper Cl) lag:
    Asthmatic individuals with 1 ED visit
    
    0.884(0.672, 1.162) 0-2 avg
    Asthmatic individuals with >1 ED visit
    
    1.084(0.661, 1.778) 0-2 avg
    Asthma/COPD individuals with >1 ED
    visit
    1.011 (0.746, 1.368) 0-2 avg
    Increment: 10|jg/m3
    
    P(x 1000) (SE(x 1000)):
    Total (nonaccidental)
    No control: 0.4834 (0.1095)
    Reported Influenza Data
    Count ID: 0.4967 (0.1089)
    11 10:0.4740(0.1090)
    Ml ID: 0.5019 (0.1096)
    RI-ID: 0.4735 (0.1091)
    SF ID: 0.6714 (0.1080)
    Estimated Influenza Data
    APHEA-2: 0.5550 (0.1076)
    11 El 0:0.5640 (0.1 073)
    Ml EID: 0.5872 (0.1100)
    RIEID: 0.5872 (0.1 074)
    SF EID: 0.6641 (0.1073)
    
    Cardiovascular
    No control: 0.8432 (0.1665)
    PpnnrtpH Inflnpnya Plata
                                                                                                                Count ID: 0.8896 (0.1662)
                                                                                                                11  10:0.8545(0.1661)
                                                                                                                Ml ID: 0.8693 (0.1674)
                                                                                                                RI-ID: 0.8649 (0.1665)
                                                                                                                SF ID: 1.0107 (0.1659)
                                                                                                                Estimated Influenza Data
                                                                                                                APHEA-2: 0.9389 (0.1654)
                                                                                                                11  El 0:0.9485 (0.1648)
                                                                                                                Ml EID: 1.0440 (0.1686)
                                                                                                                RIEID: 0.9718 (0.1653)
                                                                                                                SF EID: 1.0585 (0.1652)
                                                                                                                Notes: 11 = one indicator for all
                                                                                                                epidemics
    
                                                                                                                M1 = multiple indicators, one per
                                                                                                                epidemic
    
                                                                                                                R1 = indicators for intervals indicating
                                                                                                                the range of influenza counts
    
                                                                                                                SF = separate smooth function during
                                                                                                                epidemic periods.
    Reference: Tsai et al. (2003, 0504801
    
    Period of Study: 1994-2000
    
    Location: Kaohsiung, Taiwan
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    
    Respiratory (460-519)
    
    Circulatory (390-459)
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 81.45
    
    Range (Min, Max): (20.50, 232.00)
    Increment: 67.00 pg/m
    
    Odds Ratio (Lower Cl, Upper Cl) lag:
    
    Total (nonaccidental)
    
    1.000(0.947, 1.056) 0-2 avg
    Study Design: Bidirectional case-
    crossover
    Statistical Analyses: Conditional
    logistic regression
    Age Groups: All ages
    Copollutant:
    S02
    N02
    CO
    03
    Respiratory
    1.023(0.829, 1.264) 0-2 avg
    Circulatory
    0.971 (0.864, 1.092) 0-2 avg
    December 2009
                                    E-327
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Vajanapoom et al. (2002,
    0425421
    Period of Study: 1992-1997
    
    Location: Bangkok, Thailand
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    
    Respiratory (460-519)
    
    Cardiovascular (390-459)
    
    Other-causes
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    LOESS
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 68.0 (23.9)
    
    IQR (25th, 75th):
    
    (50.1,80.7)
    
    Copollutant (correlation): NR
    Increment: 30 pg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Total (nonaccidental)
    All ages: 2.3% (1.3, 3.3) 0-4 ma
    55-64:1.5% (-0.8, 3.9) 0-4 ma
    65-74: 4.2% (2.0, 6.3) 0-4 ma
    > 75: 3.9% (2.1, 5.6) 0-4 ma
    
    Cardiovascular
    All ages: 0.8% (-0.9, 2.4) 0
    55-64:-2.5% (-6.3, 1.3)0
    65-74: 2.9% (-0.7, 6.5) 0
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Vedal et al. (2003, 0390441
    Period of Study: Jan 1994-Dec 1996
    Location: Vancouver, British Columbia,
    Canada
    
    
    
    
    Age Groups:
    All ages
    rr c/\ wr
    ob-04 yr
    65-74 yr
    
    >75yr
    
    
    
    
    
    Outcome: Mortality:
    Total (nonaccidental) (<800)
    Respiratory (460-51 9)
    Cardiovascular (390-459)
    Study Design: Time-series
    Statistical Analyses: Poisson GAM,
    LOESS
    
    Age Groups: All ages
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM10
    Averaging Time: 24-h avg
    Mean (SD): 14.4 (5.9)
    Range (Min, Max): (4.1, 37.2)
    Copollutant (correlation): 0; r = 0.48
    S02:r = 0.76
    N02:r = 0.84
    CO: r = 0.71
    > 75: 1.6% (-1.8, 5.0)0
    Respiratory
    All ages: 5.1% (0.6, 9.6) 0-2 ma
    55-64: 1.4% (-11. 3, 14.2) 0-2 ma
    65-74: 2.8% (-9.5, 15.2) 0-2 ma
    > 75: 10.2% (-0.1, 20.5) 0-2 ma
    
    Other-causes
    All ages: 2.4% (1.3, 3.5) 0-4 ma
    55-64: 1.7% (-1.1, 4.5) 0-4 ma
    65-74: 5.6% (3. 1,8. 1)0-4 ma
    > 75: 3.7% (1.8, 5.6) 0-4 ma
    The study does not present quantitative
    results
    
    
    
    
    
    
    Reference: Venners et al. (2003,
    0899311
    Period of Study: Jan 1995-Dec 1995
    
    Location: Chongqing, China
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    cubic spline
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 146.8
    
    Range (Min, Max): (44.7, 666.2)
    
    Copollutant: S02
    
    Notes: PMi0 was measured for only 7
    mo of the study period.
    Increment: 100|jg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    1.00(0.93,1.07)0
    0.98(0.91, 1.04)1
    1.00(0.93,1.07)2
    0.96(0.90,1.03)3
    0.97(0.90, 1.03)4
    0.99(0.93,1.06)5
    Reference: Vichit-Vadakan et al. (2008,  P,utcome : M°rtQf^
    .	                      i     '  NL-M-i-^^^iH^nt-^  /Ann DQQ\
    Period of Study: Jan 1999-Dec 2003
    
    Location: Bangkok, Thailand
    Nonaccidental (AOO-R99)
    Cardiovascular (IOO-I99)
    Ischemic heart diseases (I20-I25)
    Stroke (I60-I69)
    Conduction disorder (I44-I49)
    Respiratory (JOO-J98)
    Lower Respiratory Infection (J10-J22)
    COPD (J40-J47)
    Asthma (J45-J46)
    Senility (R54)
    Study Design: Time-series
    
    Statistical Analyses: Poisson, natural
    cubic spline
    Age Groups: All ages
    0-4 yr
    5-44 yr
    18-50yr
    45-64 yr
    >50yr
    >65yr
    >75yr
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD): 52.1 (20.1)
    
    Range (Min, Max): (21.3,169.2)
    
    Copollutant (correlation): NR
    Increment: 10|jg/m3
    
    % Excess Risk (Lower Cl, Upper Cl)
    lag:
    Cause-specific mortality:
    Nonaccidental: 1.3% (0.8,1.7)0-1
    Cardiovascular: 1.9% (0.8, 3.0) 0-1
    Ischemic heart disease:
    1.5% (-0.4, 3.5)0-1
    Stroke: 2.3% (0.6, 4.0) 0-1
    Conduction disorders:
    -0.%3(-5.9, 5.6)0-1
    Cardiovascular:
    > 65 1.8 (0.2, 3.3)0-1
    Respiratory:
    All ages: 1.0 (-0.4, 2.4)0-1
    Ł1:14.6(2.9, 27.6)0-1
    > 65:1.3 (-0.8, 3.3)0-1
    LRI: <5: 7.7 (-3.6, 20.3) 0-1
    COPD: 1.3 (-1.8, 4.4)0-1
    Asthma: 7.4 (1.1,14.1)0-1
    Senility: 1.8 (0.7, 2.8)0-1
    
    Age-specific for nonaccidental
    0-4: 0.2 (-2.0,  2.4) 0-1
    5-44:0.9(0.2, 1.7)0-1
                                                                                                                18-50:1.2(0.5, 1.9
                                                                                                                45-64:1.1(0.4,1.9
                                                                                             0-1
                                                                                             0-1
                                                                                                                > 50:1.4 (0.9, 1.9)0-1
    December 2009
                                    E-328
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                                  >65:1.5(0.9,2.1)0-1
                                                                                                                  > 75: 2.2 (1.3, 3.0)0-1
    
                                                                                                                  Sex-specific for nonaccidental
                                                                                                                  Male: 1.2 (0.7,1.7)0-1
                                                                                                                  Female:  1.3 (0.7,1.9)0-1
    
                                                                                                                  Nonaccidental
                                                                                                                  1.2(0.8,1.6)0
                                                                                                                  0.9(0.6,1.3)1
                                                                                                                  0.9
                                                                                                                  0.8
                                                                          0.5, 1.3)2
                                                                          0.4,1.2)3
                                                                                                                  0.3 (-0.1, 0.7) 4
                                                                                                                  1.3
                                                                                                                  1.4
                                                                          0.8, 1.7)0-1
                                                                          0.9,1.9)0-4
                                                                                                                  Cardiovascular
                                                                                                                  1.5(0.5,2.6)0
                                                                                                                  1.7(0.7,2.7)1
                                                                                                                  1.6
                                                                                                                  0.8
                                                                          0.6, 2.6) 2
                                                                          -0.1,1.8)3
                                                                                                                  -0.1  (-1.1,0.9)4
                                                                                                                  1.9
                                                                                                                  1.9
                                                                          0.8, 3.0) 0-1
                                                                          0.6, 3.2) 0-4
                                                                                                                  Respiratory
                                                                                                                  1.0 (-0.3, 2.3)0
                                                                                                                  0.8 (-0.5, 2.0) 1
                                                                                                                     -0.1,2.3)2
                                                                                                                     0.1,2.6)3
                                                                                                                  0.7 (-0.6, 1.9)4
                                                                      1.3
                                                                                                                  1.0
                                                                                                                  1.9
                                                                                                                  a 65
                                                                                                                  1.5
                                                                          -0.4, 2.4) 0-1
                                                                          1.2,2.6)0-4
    
                                                                          0.9, 2.0) 0
                                                                          0.6,1.7)1
                                                                      1.1(0.6,1.6)2
                                                                                                                  1.2
                                                                                                                  0.7
                                                                          0.6, 1.7)3
                                                                          0.2,1.2)4
                                                                                                                  1.5(0.9,2.1)0-1
                                                                                                                  1.9(1.2,2.6)0-4
    
                                                                                                                  Sensitivity analysis:
                                                                                                                  Nonaccidental (df):
                                                                                                                  3:1.3(0.9,1.8)
                                                                                                                  4:1.2(0.8,1.7)
                                                                                                                  6:1.3(0.8, 1.7)
                                                                                                                  6, with S02:1.2 (0.8, 1.7)
                                                                                                                  6, with N02:1.0 (0.2,1.8)
                                                                                                                  6, with Os: 1.1 (0.6, 1.7)
                                                                                                                  9:1.1(0.7,1.6)
                                                                                                                  12:1.1 (0.6, 1.5)
                                                                                                                  15:1.2(0.7, 1.6)
    
                                                                                                                  Cardiovascular (df):
                                                                                                                  "  '  "  0.8, 2.7)
                                                                                                                        0.7, 2.6)
                                                                      4:1.6
                                                                                                                  6:1.7(0.7,2.7)
                                                                                                                  6, with S02: 2.0 (0.9, 3.3)
                                                                                                                  6, with N02:2.3 (0.2, 4.3)
                                                                                                                  6, with 03:1.8 (0.5, 3.2)
                                                                                                                  9:1.7(0.6,2.8)
                                                                                                                  12:1.8(0.7(03.0)
                                                                                                                  15:2.2(0.9,3.4)
    December 2009
                             E-329
    

    -------
    Study
    Reference: Villeneuve et al. (2003,
    0550511
    
    Period of Study: 1986-1999
    Location: Vancouver, Canada
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Welty et al. (2008, 1571341
    Period of Study: 1987-2000
    Location: Chicago, Illinois
    
    
    
    
    
    
    Reference: Welty and Zeger (2005,
    0874841
    
    Period of Study: 1987-2000
    Location: 100 U.S. cities (NMMAPS)
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Cardiovascular (401 -440)
    Respiratory (460-51 9)
    
    Cancer (140-239)
    Study Design: Time-series
    Statistical Analyses: Poisson, natural
    solinss
    
    Age Groups: 2 65 yr
    
    
    
    
    
    
    
    
    
    
    Outcome: Mortality:
    Total (nonaccidental)
    Study Design: Time-series
    Statistical Analyses: Poisson-Gibbs
    Sampler
    
    Bayesian Distributed Lag Model
    Age Groups: All ages
    
    
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    Study Design: Time-series
    Statistical Analyses: Bayesian
    hierarchical model
    Age Groups: All ages
    
    
    
    
    
    
    
    Concentrations1
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Daily 14.0
    
    Every 6th Day 19.6
    Range (Min, Max):
    Daily (3.8, 52.2)
    Every 6th Day (3.5, 63.0)
    Copollutant:
    S02
    CO
    N02
    n
    v-i
    PM25
    PM.n,r
    r IVI10-2.5
    
    
    
    
    
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (Min, Max): NR
    Copollutant (correlation): NR
    
    
    
    
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (Min, Max): NR
    Copollutant (correlation): NR
    
    
    
    
    
    
    
    Effect Estimates (95% Cl)
    Increment: 15.4 pg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    Nonaccidental
    3.7% (-0.5, 8.0) 0-2 avg
    2.6% -0.9,6.1)0
    2.7% -0.7, 6.2) 1
    1.9% (-1.4, 5.3)2
    Cardiovascular
    3.4% (-2.7, 9.8) 0-2 avg
    5.1% 0.0, 10.4)0
    1.3% -3.8, 6.7) 1
    0.6% (-4.3, 5.7) 2
    Respiratory
    PM10
    0.1% -9.5, 10.8 0-2 avg
    1.0% -7.5, 10.4 0
    0.4% (-7.7, 9.3) 1
    -1.3% (-8.9, 7.1)2
    Cancer
    1.2% (-6.9, 10.1) 0-2 avg
    -2.5% (-8.8, 4.3) 0
    2.3% (-4.6, 9.6) 1
    3.3% (-3.7, 10.8)2
    Increment: 10|jg/m3
    % Excess Risk (Lower Cl, Upper Cl)
    i_ „.
    lag.
    Poisson-Gibbs Sampler
    0.17% (0.01, 0.34) 3
    -0.24% (-0.73, 0.23) 0-14
    
    Unconstrained:
    -0.19% (-0.86, 0.48)0-14
    Bayesian Distributed Lag Model
    -0.21% (-0.86, 0.41)0-14
    Increment: 10|jg/m3
    
    % Increase (SE) lag:
    Distributed Lag Model:
    Seasonally-Temporally Varying
    Temperature variables: 0, 1-2, 1-7, 1-14
    S(t,1xyr): 0.229 (0.053)1
    S(t, 2 xyr): 0.220 (0.053)1
    S(t, 4 xyr): 0.1 87 0.050 1
    S(t, 8 xyr): 0.1 78 0.049 1
    Temperature variables: 0, 1-2, 1-7,
    1-14, 0x1-2, 0x1-7
    1-2 x 1-7
    S(t, 1 xyr): 0.1 95 0.048 1
    S(t, 2 xyr): 0.200 0.051 1
                                                                                                                  Sft, 4 xyr): 0.176 (0.050)1
                                                                                                                  S(t, 8 xyr): 0.149 (0.050)1
    
                                                                                                                  Distributed Lag Model: Nonlinear
                                                                                                                  Temperature variables: 0,1-2,1-7,1-14
                                                                                                                  S(t, 4 xyr): 0.239 (0.053)1
    
                                                                                                                  Temperature variables: 0,1-2,1-7,
                                                                                                                  1-14,0x1-2,0x1-7,1-2x1-7
                                                                                                                  S(t, 4 xyr): 0.172 (0.045)1
    
                                                                                                                  Temperature variables: S(0,2), 3(1-2,2),
                                                                                                                  3(1-7,2), 3(1-14,2)
                                                                                                                  S(t, 4 xyr): 0.186 (0.046)1
    
                                                                                                                  Temperature variables: 3(0,2), 3(1-2,2),
                                                                                                                  3(1-7,2), 3(1-14,2), 3(0x1-2,2),
                                                                                                                  3(0x1-7,2), 3(1-2x1-7,2)
                                                                                                                  S(t, 4 xyr): 0.189 (0.047)1
    December 2009
    E-330
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                   Temperature variables: S(0,4), 3(1-2,4),
                                                                                                                   3(1-7,4), 3(1-14,4)
                                                                                                                   S(t, 4 xyr): 0.175 (0.046)1
    
                                                                                                                   Temperature variables: 3(0,4), 3(1-2,4),
                                                                                                                   3(1-7,4), 3(1-14,4), 3(0x1-2,4),
                                                                                                                   3(0x1-7,4), 3(1-2x1-7,4)
                                                                                                                   S(t, 4 xyr): 0.190 (0.048)1
    
                                                                                                                   Temperature variables: 0,1-2,1-7
                                                                                                                   S(t, 4 xyr): 0.252 (0.053)1
    
                                                                                                                   Temperature variables: 0,1-2,1-7,
                                                                                                                   0x1-2,0x1-7, 1-2x1-7
                                                                                                                   S(t, 4 xyr): 0.186 (0.044)1
    
                                                                                                                   Temperature variables: 3(0,2), 3(1-2,2),
                                                                                                                   3(1-7,2)
                                                                                                                   S(t, 4 xyr): 0.198 (0.046)1
    
                                                                                                                   Temperature variables: 3(0,2), 3(1-2,2),
                                                                                                                   3(1-7,2), 3(0x1-2,2), 3(0x1-7,2),
                                                                                                                   3(1-2x1-7,2)
                                                                                                                   S(t, 4 xyr): 0.201 (0.047)1
    
                                                                                                                   Temperature variables: 3(0,4), 3(1-2,4),
                                                                                                                   3(1-7,4)
                                                                                                                   S(t, 4 xyr): 0.189 (0.045)1
    
                                                                                                                   Temperature variables: 3(0,4), 3(1-2,4),
                                                                                                                   3(1-7,4), 3(0x1-2,2), 3(0x1-7,4),
                                                                                                                   3(1-2x1-7,2)
                                                                                                                   S(t, 4 xyr): 0.205 (0.047)1
    
                                                                                                                   Temperature variables: 3(0,4), 3(1-2,4)
                                                                                                                   S(t, 4 xyr): 0.250 (0.045)1
    
                                                                                                                   Temperature variables: 3(0,4), 3(1-2,4),
                                                                                                                   3(0x1-2,4)
                                                                                                                   S(t, 4 xyr): 0.253 (0.044)1
    
                                                                                                                   Temperature variables: 3(0,4)
                                                                                                                   S(t, 4 xyr): 0.220 (0.045)1
                                                                                                                   Notes: 0 indicates current-day
                                                                                                                   temperature
    
                                                                                                                   1-r indicates avg of lag 1 through lag r
                                                                                                                   temperature
    
                                                                                                                   3 (, p) indicates a natural spline smooth
                                                                                                                   with p degrees of freedom.
    
                                                                                                                   3 (t, a x yr) indicates the natural spline
                                                                                                                   smooth of time with degrees of freedom
                                                                                                                   equal to a x (number of yr of data).
    December 2009                                                     E-331
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Wong et al. (2007, 0983911
    
    Period of Study: Jan 1998-Dec 1998
    
    Location: Hong Kong, China
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    
    Cardiorespiratory (390-519)
    
    Study Design: Main analysis: Time-
    series
    
    Sensitivity analysis: Case-crossover,
    case-only
    
    Statistical Analyses: Main analysis:
    Poisson GAM
    
    Sensitivity analysis: Conditional
    logistic regression
    
    Age Groups: 2 30 yr; 2 65 yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD):
    
    48.1  (24.3)
    
    Range (Min, Max):
    
    (15.5, 140.5)
    
    Copollutant:
    
    N02
    
    S02
    
    03
    Increment: 10|jg/m
    
    % Excess Risk (Lower Cl, Upper Cl)
    lag:
    Main Analysis
    Nonaccidental
    Smokers:
    > 301:.80% (0.35, 3.26)0
    1.77% (0.46, 3.11)2
    > 65: 3.20% (1.36, 5.07)0
    2.42% (0.73, 4.13)2
    
    Never-smokers
    > 30:-0.37% (-2.23, 1.52)0
    -0.03% (-1.72, 1.66)2
    >65P-0.70% (-2.81,  1.46)0
    -0.13% (-2.04, 1.80)2
    
    Cardiorespiratory
    Smokers
    > 30:1.43% (-0.86, 3.78)0
    2.32% (0.24, 4.44) 2
    > 65: 2.98% (0.47, 5.55) 0
    2.61% (0.31, 4.95) 2
    
    Never-smokers
    > 30: 0.02% (-2.75, 2.87)0
    -0.79% (-3.33, 1.82)2
    > 65: 0.25% (-2.62, 3.19)0
    -0.66% (-3.29, 2.04) 2
    
    Sensitivity Analysis
    Poisson Regression
    Nonaccidental
    > 30:1.81% (0.21, 3.44)0
    1.93% (0.32, 3.56)2
    1.99% (0.14, 3.87)0-3
    > 65: 2.31% (0.37, 4.29)0
    2.16% (0.20, 4.15)2
    2.57% (0.30, 4.89) 0-3
    
    Cardiorespiratory
    > 30:1.04% (-1.45, 3.59)0
    2.18% (-0.35, 4.77)2
    1.66% (-1.24, 4.64)0-3
    > 65:1.69% (-0.93, 4.37)0
    2.44% (-0.23, 5.18)2
    2.30% (-0.80, 5.50) 0-3
    
    Case-only: Logistic Regression
    Nonaccidental
    > 30:1.79% (0.21, 3.37)0
    1.94% (0.33, 3.56)2
    > 65: 2.30% (0.42, 4.17)0
    2.16% (0.26, 4.07)2
    
    Cardiorespiratory
    > 30:1.01% (-1.37, 3.40)0
    2.16% (-0.28, 4.61)2
    > 65:1.65% (-0.96, 4.27)0
    2.42% (-0.27, 5.12)2
    
    Case-crossover
    Nonaccidental
    > 30: 2.54% (0.35, 4.78) 0
    1.35% (-0.81, 3.56) 2
    > 65: 3.96% (1.37, 6.63)0
    2.20% (-0.35, 4.81)2
    
    Cardiorespiratory
    > 30: 0.48% (-2.74, 3.80)0
    3.24% (-0.03, 6.61)2
    > 65: 2.17% (-1.40, 5.86)0
    3.43% (-0.13, 7.13)2	
    Reference: Wong et al. (2007, 0932781  Outcome: Mortality:
    
    Period of Study: Jan 1998-Dec 1998    Total (nonaccidental) (<800)
                                        Pollutant: PMi0
                                        Averaging Time: 24-h avg
                                        Mean (SD):
                                        48.1 (24.3)	
                                        Increment: 10|jg/m
                                        % Excess Risk (Lower Cl, Upper Cl)
                                        lag:
                                        Nonaccidental
    December 2009
                                    E-332
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Location: Hong Kong, China
    Cardiorespiratory (390-519)
    
    Study Design: Main analysis: Time-
    series
    
    Sensitivity analysis: Case-only
    
    Statistical Analyses: Main analysis:
    Poisson GAM, natural cubic spline
    
    Sensitivity analysis: Logistic
    regression
    
    Age Groups: 2 30 yr; 2 65 yr
    Range (Min, Max): (15.5,140.5)
    Copollutant:
    N02
    S02
    03
    Exercise
    > 30: 0.13% (-1.16, 1.44 1
    > 65: 0.24% (-1.16, 1.67 1
    
    Never-exercise
    > 30:1.04% (0.07, 2.02)1
    > 65:1.26% (0.27, 2.27)1
    
    Cardio-respiratory
    Exercise
    > 30: 0.46% (-1.43, 2.39 1
    > 65: 0.30% (-1.65, 2.29 1
    
    Never-exercise
    > 30: 0.97% (-0.36, 2.32)1
    > 65: 0.98% (-0.45, 2.43)1
    
    Difference in % Excess Risk (Exercise
    vs. Never-Exercise)
    Nonaccidental
    Poisson Regression
    > 30:-2.86% (-4.03 to-1.67)1
    > 65:-3.06% (-4.37 to-1.74)1
    
    Case-only
    >30:-2.91% -4.04to-1.77 1
    > 65:-3.12% -4.38 to-1.84 1
    
    Cardiorespiratory
    Poisson regression
    > 30:-2.55% (-4.32 to-0.75)1
    > 65:-2.64% (-4.48 to-0.76)1
    
    Case-only
    > 30:-2.63% -4.32 to-0.92 1
    > 65:-2.73% -4.50 to-0.92 1
    
    Adjusted Case-only
    Nonaccidental
    Sex
                                                                                                                 > 30: -2.88%
                                                                                                                 > 65: -3.09%
                                                                                         -1.73 to-4.01
                                                                                         -1.82 to-4.35
                                                                                                                 Education
                                                                                                                 > 30:-2.94% (-1.80 to-4.07)1
                                                                                                                 > 65:-3.18% (-1.90 to -4.44)1
                                                                                                                 Job
                                                                                                                 > 30:-2.88% (-1.74 to-4.02)1
                                                                                                                 > 65:-3.11% (-1.83 to -4.37)1
    
                                                                                                                 Smoking
                                                                                                                 > 30:-2.82% (-1.66 to-3.96)1
                                                                                                                 > 65:-2.97% (-1.68 to-4.25)1
    
                                                                                                                 Illness time
                                                                                                                 > 30:-2.94% (-1.80 to-4.07)1
                                                                                                                 > 65:-3.16% (-1.88 to -4.42)1
    
                                                                                                                 Cardiorespiratory
                                                                                                                 Sex
                                                                                                                 > 30:-2.61% (-0.89 to-4.29)1
                                                                                                                 > 65:-2.71% (-0.90 to-4.48)1
    
                                                                                                                 Education
                                                                                                                 > 30:-2.58% (-0.85 to-4.27)1
                                                                                                                 > 65:-2.77% (-0.95 to-4.54)1
    
                                                                                                                 Job
                                                                                                                 > 30:-2.68% -0.96 to-4.37  1
                                                                                                                 > 65:-2.68% -0.88 to-4.46  1
    
                                                                                                                 Smoking
                                                                                                                 > 30:-2.46% (-0.73 to-4.17)1
                                                                                                                 > 65:-2.50% (-0.68 to-4.29)1
    
                                                                                                                 Illness Time
                                                                                                                 > 30:-2.63% (-0.91 to-4.32)1
                                                                                                                 > 65:-2.73% (-0.92 to-4.51)1
    December 2009
                                     E-333
    

    -------
                 Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                                                            Case-only by Exercise Group (Never as
                                                                                                            Reference)
                                                                                                            Nonaccidental
                                                                                                            >30
                                                                                                            Low:-3.34% (-5.77 to-0.85)1
                                                                                                            Moderate:-6.32% (-8.55 to-4.03)1
                                                                                                            High:-1.74% (-3.06 to-0.40)1
                                                                                                            265
                                                                                                            Low:-3.79% (-6.67 to-0.82)1
                                                                                                            Moderate: -7.78% (-10.39 to -5.10) 1
                                                                                                            High:-1.77% (-3.21 to-0.31)1
    
                                                                                                            Cardiorespiratory
                                                                                                            >30
                                                                                                            Low: -3.95% (-7.77, 0.04)  1
                                                                                                            Moderate: -8.50% (-11.84  to -5.02) 1
                                                                                                            High:-0.62% (-2.58, 1.38)1
                                                                                                            >65
                                                                                                            Low:-3.97% (-8.17, 0.43)1
                                                                                                            Moderate:-9.42% (-13.00 to-5.69)1
                                                                                                            High:-0.68% (-2.71, 1.38)1	
    Reference: Wong et al. (2002, 0254361 Outcome: Mortality:
    Period of Study: 1995-1998
    
    Location: Hong Kong, China
    Respiratory (461-519)
    
    COPD (490-496)
    
    Pneumonia & Influenza (480-487)
    
    Cardiovascular (390-459)
    
    IHD (410-414)
    
    Cerebrovascular (430-438)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    
    Age Groups: 2 30 yr; 2 65 yr
    Pollutant: PM10
    
    Averaging Time: 24-h avg
    
    Mean (SD):
    
    51.53(24.79)
    
    Range (Min, Max):
    
    (14.05, 163.79)
    
    Copollutant (correlation):
    
    N02:r = 0.780
    
    S02:r = 0.344
    
    03:r = 0.538
    Increment: 10|jg/m3
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Respiratory
    1.008(1.001to1.014)1
    COPD
    1.017(1.002, 1.033)0-3
    Pneumonia & Influenza
    1.007(0.999,1.015)2
    Cardiovascular
    1.003(0.998,1.016)2
    IHD
    1.013(1.001, 1.025)0-3
    Cerebrovascular
    1.007(0.998,1.016)2
    Respiratory
    PMio+S02+03+N02:
    1.005(0.992, 1.010)1
    COPD
    PMio+S02+03+N02:
    0.991 (0.968, 1.015)0-3
    PMio+03+N02:
    0.993(0.970,1.016)0-3
    Pneumonia & Influenza
    PMio+S02+03+N02:
    1.002(0.991,1.013)2
    IHD
    0.994(0.978, 1.009)0-3	
    December 2009
                                   E-334
    

    -------
    Study
    Reference: Wong et al. (2008, 1571521
    Period of Study:
    Bangkok: 1999-2003
    Hong Kong: 1996-2002
    ShanghaiS Wuhan: 2001-2004
    Location: Bangkok, Thailand
    Design & Methods
    Outcome (ICD10): Mortality:
    Natural causes (AOO-R99)
    Cardiovascular (IOO-I99)
    Respiratory (JOO-J98)
    Study Design: Time-series
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD):
    Bangkok: 52.0
    Hong Kong: 51. 6
    Shanghai: 102.0
    Wuhan: 141.8
    Effect Estimates (95% Cl)
    Increment: 10|jg/m3
    % Excess Risk (Lower Cl, Upper Cl)
    lag:
    Random Effects (4 cities)
    Natural causes: 0.55% (0.26, 0.85 0-1
    Cardiovascular: 0.58% (0.22, 0.93 0-1
    Respiratory: 0.62% (0.22, 1.02)0-1
    Random Effects (3 Chinese cities)
    Hong Kong, Shanghai, and Wuhan,
    China
    natural splines
    
    Age Groups: All ages
    
    >65yr
    
    >75yr
    Range (Min, Max):
    Bangkok: (21.3,169.2)
    Hong Kong: (13.7,189.0)
    Shanghai: (14.0, 566.8)
    Wuhan: (24.8, 477.8)
    
    Copollutant:
    N02
    S02
    03
    Natural causes: 0.37% (0.21, 0.54) 0-1
    Cardiovascular: 0.44% (0.19, 0.68) 0-1
    Respiratory: 0.60% (0.16,1.04) 0-1
    Sensitivity Analysis
    Random Effects (4 cities)
    Omit PM,o>95th: 0.53% (0.27, 0.78) 0-1
    Omit PM10>75th: 0.53% (0.29, 0.78) 0-1
    Omit PM10>180 pg/m3:
    0.65% (0.24, 1.06)0-1
    Omit stations with high traffic source:
    0.55% (0.26, 0.85) 0-1
    Warm season-dichotomous variables:
    0.86% (0.11,1.60) 0-1
    Add temperature at lag 1-2 days: 0.51%
    (0.23, 0.79) 0-1
    Add temperature at lag 3-7 days: 0.35%
    (0.14,0.57)0-1
    Daily PMio defined by centering: 0.54%
    (0.26, 0.82) 0-1
    Natural spline with (8, 4,  4f: 0.54%
    (0.26,0.81)0-1
    Penalized spline:
    0.52% (0.26, 0.77) 0-1
    Random Effects (3 Chinese cities)
    Omit PM,o>95th: 0.47% (0.21, 0.73) 0-1
    Omit PM10>75th: 0.55% (0.24, 0.85) 0-1
    Omit PM10>180 pg/m3:
    0.46% (0.15, 0.76)0-1
    Omit stations with high traffic source:
    0.38% (0.20, 0.57) 0-1
    Warm season-dichotomous variables:
    0.43% (0.10, 0.76)0-1
    Add temperature at lag 1-2 days:
    0.36% (0.18, 0.53)0-1
    Add temperature at lag 3-7 days:
    0.25% (0.10, 0.40)0-1
    Daily PM10 defined by centering:
    0.37% (0.21, 0.53) 0-1
    Natural spline with (8, 4,  4f:
    0.36% (0.23, 0.49) 0-1
    Penalized spline:
    0.34% (0.23, 0.45) 0-1	
    Reference: Wong et al. (2008,1571511
    
    Period of Study: Jan 1996-Dec 2002
    
    Location: Hong Kong
    Outcome (ICD10): Mortality:
    
    Nonaccidental (AOO-T99
    
    ZOO-Z99)
    
    Cardiovascular (IOO-I99)
    
    Respiratory (JOO-J98)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GLM,
    natural splines
    
    Age Groups: All ages
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    
    Mean (SD): 51.6 (25.3)
    
    Range (Min, Max): (13.5,188.5)
    
    Copollutant:
    
    N02
    
    S02
    
    03
    Increment: 10 pg/m
    % Excess Risk (Lower Cl, Upper Cl)
    lag:
    Nonaccidental:
    Low SDI
    0.37 (-0.10,0.84)0
    0.40 (-0.04, 0.84) 1
    0.14 (-0.28, 0.57)2
    -0.12 (-0.55, 0.30)3
    -0.14 (-0.56, 0.28)4
    
    Middle SDI
    0.70(0.34, 1.07)0
    0.48  0.14, 0.82  1
    0.35 (0.02, 0.68) 2
    0.18 (-0.14, 0.51)3
    0.17 (-0.16, 0.50)4
                                                                                                                 High SDI
                                                                                                                 0.22 (-0.29, 0.73
                                                                                                                 0.46 (-0.01, 0.94
                                                                                                                 0.29 (-0.17, 0.75)2
                                                                                                                 -0.05
                                                                                                                 -0.06
                                                                                  -0.51,0.40)3
                                                                                  -0.51,0.40)4
                                                                                                                 All areas
    December 2009
                                     E-335
    

    -------
                  Study                       Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                  0.45(0.19,0.72)0
                                                                                                                  0.40  0.15, 0.64  1
                                                                                                                  0.22 (-0.02, 0.45) 2
                                                                                                                  0.00 (-0.24, 0.23) 3
                                                                                                                  0.03 (-0.20, 0.26) 4
    
                                                                                                                  Cardiovascular:
                                                                                                                  Low SDI
                                                                                                                  0.14 (-0.77, 1.06)0
                                                                                                                  0.64 (-0.21, 1.49)1
                                                                                                                  0.24 (-0.58, 1.07)2
                                                                                                                  -0.27 (-1.09, 0.55)3
                                                                                                                  0.01 (-0.80, 0.83) 4
    
                                                                                                                  Middle SDI
                                                                                                                  0.66(0.00,1.34)0
                                                                                                                  0.49 (-0.13, 1.12)1
                                                                                                                  0.80(0.20,1.40)2
                                                                                                                  0.65(0.06,1.25)3
                                                                                                                  0.52 (-0.07, 1.12)4
    
                                                                                                                  High SDI
                                                                                                                  0.83 (-0.08, 1.75)0
                                                                                                                  0.89(0.04,1.75)1
                                                                                                                  0.12 (-0.70, 0.95)2
                                                                                                                  -0.09 (-0.91, 0.73) 3
                                                                                                                  0.04 (-0.77, 0.86) 4
    
                                                                                                                  All areas
                                                                                                                  0.52(0.05,1.00)0
                                                                                                                  0.58(0.14,1.03)1
                                                                                                                  0.43 (0.00, 0.86) 2
                                                                                                                  0.14 (-0.28, 0.57)3
                                                                                                                  0.23 (-0.20, 0.65) 4
                                                                                                                  Respiratory:
                                                                                                                  Low SDI
                                                                                                                  00.69 (-0.44, 1.82
                                                                                                                  10.55 (-0.50, 1.61
                                                                                                                  2 0.36 (-0.66, 1.39)2
                                                                                                                  3 -0.24
                                                                                                                  4-0.17
    -1.25,0.78)3
    -1.17,0.85)4
                                                                                                                  Middle SDI
                                                                                                                  0.31 (-0.50,  1.13)0
                                                                                                                  0.77(0.01,1.53)1
                                                                                                                  0.85(0.12, 1.59)2
                                                                                                                  0.66 (-0.07,  1.39 3
                                                                                                                  0.69 (-0.03,  1.42 4
    
                                                                                                                  High SDI
                                                                                                                  0.27 (-0.85,  1.40)0
                                                                                                                  0.72 (-0.32,  1.78)1
                                                                                                                  1.46  0.45, 2.47)2
                                                                                                                  0.70 (-0.30,  1.71)3
                                                                                                                  0.48 (-0.52,  1.48)4
    
                                                                                                                  All areas
                                                                                                                  0.39 (-0.20,  0.99) 0
                                                                                                                  0.70(0.15, 1.26)1
                                                                                                                  0.89(0.36,1.42)2
                                                                                                                  0.45 (-0.08,  0.98) 3
                                                                                                                  0.43 (-0.10,0.96)4
    
                                                                                                                  High SDI vs. Middle SDI
                                                                                                                  Nonaccidental: 0.23 (-0.25, 0.72) 0-1
                                                                                                                  Cardiovascular: 0.49 (-0.40,1.40) 0-1
                                                                                                                  Respiratory: 0.49 (-0.58,1.58)0-1
    
                                                                                                                  High SDI vs. Low SDI
                                                                                                                  Nonaccidental: 0.12 (-0.42, 0.67) 0-1
                                                                                                                  Cardiovascular: 0.82 (-0.20,1.86) 0-1
                                                                                                                  Respiratory:-0.15 (-1.39,1.10)0-1
    
                                                                                                                  Trend Test
                                                                                                                  Nonaccidental: 0.04 (-0.15, 0.22) 0-1
                                                                                                                  Cardiovascular: 0.27 (-0.07, 0.61) 0-1
                                                                                                                  Respiratory: -0.04 (-0.46, 0.37)
    December 2009                                                    E-336
    

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                 Study                       Design & Methods                Concentrations1             Effect Estimates (95% Cl)
                                                                                                            0-1 SDI = Social Deprivation Index. The
                                                                                                            higher the SDI the lower the SES of the
                                                                                                            individual.
    Reference: Yang et al. (2004, 0556031   Outcome: Mortality:                  Pollutant: PMi0                      Increment: 31.43 pg/m3
    Period of Study: 1994-1998           Nonaccidental (<800)                 Averaging Time: 24-h avg             Odds Ratio (Lower Cl, Upper Cl) lag:
    Location: Taipei, Taiwan               Circulatory (390-459)                 Mean (SD): 51. 99                    Nonaccidental
                                       Respiratory (460-51 9)                 Range (Min, Max): (13.71, 211.30)      0.995(0.971,  1.020)0
                                       Study Design: Bi-directional case-      Copollutant:                        Respiratory
                                                                            2
                                                                         N02                                0.986(0.906,1.074)0
                                       Statistical Analyses: Conditional       CO
                                       logistic regression                    03                                 Circulatory
                                       Age Groups: All ages                                                   0.988(0.942,1.035)
    December 2009                                                  E-337
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Zanobetti et al. (2003,
    0428121
    
    Period of Study: 1990-1997
    
    Location: 10 European cities
    (APHEA2)
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Circulatory (390-459)
    
    Respiratory (460-519)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM
    
    Age Groups:
    15-64yr
    
    65-74 yr
    
    >75yr
    Pollutant: PM,0
    
    Averaging Time: 24-h avg
    Mean (SD):
    Athens: 42.7 (12.9)
    Budapest: 41 (9.1)
    Lodz: 53.5 (15.5)
    London: 28.8 (13.7)
    Madrid: 37.8 (17.7)
    Paris: 22.5 (11.5)
    Prague: 76.2 (45.7)
    Rome: 58.7 (17.4)
    Stockholm: 15.5 (7.9)
    Tel Aviv: 50.3 (57.5)
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Cardiovascular
    0.69% (0.31, 1.08)0-1 avg
    40-day distributed lag
    1.99% (1.44, 2.54)
    4th degree
    1.97% (1.38, 2.55)
    
    Unrestricted
    Respiratory
    0.74% (-0.17, 1.66) 0-1 avg
    40-day distributed lag
    4.21% (1.70, 6.79)
    4th degree
    4.20% (1.08, 7.42)
    
    Unrestricted
    Unrestricted distributed lags
    Cardiovascular
    1.34% (0.89, 1.79)20
    1.72% (1.20, 2.25)30
    1.97% (1.38, 2.55)40
    
    Respiratory
    1.71% (-0.65, 4.12)20
    2.62% (0.19, 5.11)30
    4.20% (1.08, 7.42)40
    40-day lags
    Nonaccidental
    15-64
    -0.25% (-0.87, 0.36)
    4th degree
    -0.01 (-0.76, 0.75)
    Unrestricted
    65-74
    0.78% (0.23, 1.33)
    4th degree
    0.74% (0.02, 1.45)
    Unrestricted
    >75
    1.84% (0.92, 2.78)
    4th degree
    1.94% (1.07, 2.81)
    Unrestricted
    
    Cardiovascular
    65-74
    2.06% (1.05, 3.09)
    4th degree
    1.62(0.54,2.70)
    Unrestricted
    >75
    2.35% (1.42, 3.29)
    4th degree
    2.52% (1.57, 3.48)
    Unrestricted
    
    Respiratory
    >75
    4.57% (1.25, 7.99)
    4th degree
    4.52% (0.89, 8.28)
    Unrestricted
    December 2009
                                     E-338
    

    -------
    Study
    Reference: Zeka et al. (2005, 0880681
    Period of Study: Jan 1989-Dec 2000
    Location: 20 U.S. cities
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Zeka et al. (2006, 0887491
    Period of Study: Jan 1989-Dec 2000
    Location: 20 U.S. cities
    
    
    Design & Methods
    Outcome (ICD10): Mortality:
    All-cause (nonaccidental) (V01-Y98)
    Heart Disease (101 -151)
    IHD(I20-I25)
    
    Myocardial infarction (121, 122)
    Dysrhythmias (I46-I49)
    Heart failure (ISO)
    Stroke (I60-I69)
    
    Respiratory (JOO-J99)
    Pneumonia (J12-J18)
    COPD (J40-J44, J47)
    Study Design: Time-stratified case-
    crossover
    
    Statistical Analyses: Conditional
    logistic regression
    Age Groups: All ages
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome (ICD10): Mortality:
    All-cause (nonaccidental) (V01-Y98)
    Heart Disease (101 -151)
    Myocardial infarction (121, 122)
    Stroke (I60-I69)
    Respiratory (JOO-J99)
    Study Design: Time-stratified case-
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD):
    Birmingham: 31.9 (18.0) pg/m3
    Boulder: 22.1 (11.3)
    Caton:26.6(11.5)
    Chicago: 33.7 (16.4)
    Cincinnati: 31. 4 (13.9)
    Cleveland: 37.5 (18.7)
    Colorado Springs: 24.0 (13.2)
    Columbus: 28.5 (12.5)
    Denver: 28.5 (12.8)
    Detroit: 32. 1(1 7.7)
    Honolulu: 15.9 (6.8)
    Minneapolis: 24.7 (12.3)
    Nashville: 30.1 (12.1)
    New Haven: 25.4 (14.4)
    Pittsburgh: 30.2 (18.5)
    Provo: 33.7 (22.2)
    Seattle: 26.4 (14.7)
    Salt lake City: 35.0 (20.8) u
    Terra Haute: 29.2 (14.6) u
    Youngstown: 30.8 (13.9)
    Range (Min, Max): NR
    Copollutant (correlation): NR
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM,0
    Averaging Time: 24-h avg
    Mean (SD):
    Birmingham: 31. 9 (18.0) pg/m3
    Boulder: 22.1 (11.3)
    Caton: 26.6(11.5)
    Chicago: 33.7 (16.4)
    Cincinnati: 31. 4 (13.9)
    Cleveland: 37.5 (18.7)
    Colorado Springs: 24.0 (13.2)
    Effect Estimates (95% Cl)
    Increment: 10|jg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    Single-lag model
    All-Cause (nonaccidental)
    0.20% (0.08, 0.32) 0
    0.35% (0.21, 0.49)1
    0.24% (0.14, 0.34)2
    Respiratory
    0.34% (-0.07, 0.75) 0
    0.52% (0.15, 0.89)1
    0.51% (0.16, 0.86)2
    COPD
    -0.06% (-0.63, 0.51)0
    0.43% (-0.14, 1.00 1
    0.39% (-0.16, 0.94 2
    Pneumonia
    0.50% (0.09, 1.09)0
    0.59% (-0.12, 1.30)1
    0.82% (0.25, 1.39)2
    Heart disease
    0.12% (-0.06, 0.30)0
    0.30% (0.12, 0.48)1
    0.37% (0.17, 0.57)2
    IHD
    0.19% (-0.03, 0.41)0
    0.41% (0.19, 0.63)1
    0.43% (0.10, 0.76)2
    Myocardial Infarction
    0.36% (-0.05, 0.77 0
    0.17% (-0.18, 0.52 1
    0.13% (-0.22, 0.48)2
    Heart Failure
    0.17% (-0.63, 0.97)0
    -0.01% (-0.81, 0.79)1
    0.78% (-0.004, 1.56)2
    Dysrhythmias
    -0.23% (-1.41, 0.95)0
    0.37% (-0.47, 1.21 1
    0.33% (-0.55, 1.21 2
    Stroke
    0.09% (-0.49, 0.60 0
    0.41% (-0.02, 0.84 1
    0.14% (-0.27, 0.55)2
    Unconstrained distributed lag model
    All-cause (nonaccidental)
    0.45% (0.25, 0.65) 0-3
    Respiratory
    0.87% (0.38, 1.36)0-3
    COPD
    0.43% (-0.35, 1.21)0-3
    Pneumonia
    1.24% (0.46, 2.02)0-3
    Heart Disease
    0.50% (0.25, 0.75) 0-3
    IHD
    0.65% (0.32, 0.98)
    Myocardial Infarction
    0.36% (-0.25, 0.97) 0-3
    Heart Failure
    0.60% (-0.50, 1.70)0-3
    Dysrhythmias
    0.20% (-1.03, 1.43)0-3
    Stroke
    0.46% (-0.13, 1.05)0-3
    Increment: 10|jg/m3
    % Increase (Lower Cl, Upper Cl)
    lag: All-cause (nonaccidental)
    Male: 0.46% (0.28 0.64) 1-2 avg
    Female: 0.37% (0.17, 0.57) 1-2 avg
    White: 0.40% (0.22, 0.58) 1-2 avg
    Black: 0.37% (-0.02, 0.76) 1-2 avg
    Age:
    <65: 0.25% (0.01, 0.49) 1-2 avg
    75: 0.23% (-0.06, 0.52) 1-2 avg
    December 2009
    E-339
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                        crossover
    
                                        Statistical Analyses: Conditional
                                        logistic regression
    
                                        Age Groups:
    
                                        All ages
    
                                        <65yr
    
                                        65-75 yr
    
                                        >75yr
                                 Columbus: 28.5 (12.5)
                                 Denver: 28.5 (12.8)
                                 Detroit: 32.1(17.7)
                                 Honolulu: 15.9 (6.8)
                                 Minneapolis: 24.7 (12.3)
                                 Nashville: 30.1 (12.1)
                                 New Haven: 25.4 (14.4)
                                 Pittsburgh: 30.2 (18.5)
                                 Provo: 33.7 (22.2)
                                 Seattle: 26.4 (14.7)
                                 Salt lake City: 35.0 (20.8)
                                 Terra Haute: 29.2 (14.6)
                                 Youngstown: 30.8 (13.9)
                                 Range (Min, Max): NR
    
                                 Copollutant (correlation): NR
                                >75: 0.64% (0.44, 0.84) 1-2 avg
    
                                Educational Attainment:
                                Low (<8 yr):
                                0.62% (0.29, 0.95) 1-2 avg
                                Medium (8-12 yr):
                                0.36% (0.12, 0.60) 1-2 avg
                                High(>12yr):
                                0.27% (-0.004, 0.54) 1-2 avg
    
                                Location of Death:
                                In hospital: 0.22% (0.04, 0.40) 1-2 avg
                                Out of hospital:
                                0.71% (0.51, 0.91) 1-2 avg
    
                                Season:
                                Winter: 0.28% (0.04, 0.52) 1-2 avg
                                Summer:  0.19% (-0.22, 0.60) 1-2 avg
                                Transition (spring/fall):
                                0.49% (0.25, 0.73) 1-2 avg
    
                                Respiratory
                                Male: 0.71% (0.004, 1.42)0-3
                                Female: 1.04% (0.33,1.75)0-3
                                White: 0.88% (0.33, 1.43)0-3
                                Black: 0.71% (-0.56,1.98)0-3
    
                                Age:
                                <65: 0.94% (-0.31, 2.19) 0-3
                                65-75: 0.87% (-0.25, 1.99)0-3
                                >75: 0.88% (0.17, 1.59)0-3
    
                                Educational Attainment:
                                Low (<8 yr):
                                0.82% (-0.32, 1.96)0-3
                                Medium (8-12 yr):
                                0.88% (0.12, 1.64)0-3
                                High(>12yr):
                                0.88% (-0.04, 1.80)0-3
    
                                Location of Death:
                                In hospital: 0.78% (0.17,1.39)0-3
                                Out of hospital: 1.09% (0.25,1.93) 0-3
    
                                Season:
                                Wnter: -0.007% (-0.87, 0.86) 0-3
                                Summer:  0.69% (-0.68, 2.06) 0-3
                                Transition (spring/fall):
                                1.57% (0.86, 2.28)0-3
    
                                Heart Disease
                                Male: 0.54% (0.23, 0.85) 2
                                Female: 0.46% (0.15, 0.77)2
                                White: 0.50% (0.25, 0.75) 2
                                Black: 0.64% (0.13,1.15)2
                                                                                                                 <65: 0.04% (-0.45, 0.53) 2
                                                                                                                 65-75: 0.60% (0.13,  1.07)2
                                                                                                                 >75: 0.65% (0.30, 1.00)2
    
                                                                                                                 Educational Attainment:
                                                                                                                 Low (<8 yr):
                                                                                                                 0.72% (0.23, 1.21)2
                                                                                                                 Medium (8-12 yr):
                                                                                                                 0.38% (0.07, 0.69) 2
                                                                                                                 High(>12yr):
                                                                                                                 0.54% (0.13, 0.95)2
    
                                                                                                                 Location of Death:
                                                                                                                 In hospital: 0.15% (-0.14, 0.44)2
                                                                                                                 Out of hospital: 0.93% (0.60,1.26) 2
    
                                                                                                                 Season:
                                                                                                                 Wnter: 0.41% (-0.002, 0.82)2
                                                                                                                 Summer: 0.52 (0.03,1.01)2
                                                                                                                 Transition (spring/fall):
                                                                                                                 0.56% (0.13, 0.99)2	
    December 2009
                             E-340
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
    
                                                                                                               Myocardial Infarction
                                                                                                               Male: 0.21% (-0.40, 0.82)0
                                                                                                               Female: 0.59% (0.08,1.10)0
                                                                                                               White: 0.24% (-0.27, 0.75) 0
                                                                                                               Black: 0.99% (0.05,1.93)0
                                                                                                               <65: 0.12% (-0.76, 1.00)0
                                                                                                               65-75: 0.92% (0.21, 1.63)0
                                                                                                               >75: 0.16% (-0.58, 0.90)0
    
                                                                                                               Educational Attainment:
                                                                                                               Low (<8yr): 0.33% (-0.83, 1.49)0
                                                                                                               Medium (8-12 yr): 0.79% (0.28,1.30) 0
                                                                                                               High (>12yr):-0.13% (-0.82, 0.56)0
    
                                                                                                               Location of Death:
                                                                                                               In hospital: 0.34% (-0.11, 0.79)0
                                                                                                               Out of hospital: 0.48% (-0.23,1.19) 0
    
                                                                                                               Season:
                                                                                                               Winter: 0.32% (-0.37,1.01)0
                                                                                                               Summer: 0.30% (-0.82,1.42)0
                                                                                                               Transition (spring/fall):
                                                                                                               0.38%-0.31,1.07)0
    
                                                                                                               Stroke
                                                                                                               Male: 0.11% (-0.58, 0.80)1
                                                                                                               Female: 0.59% (-0.04,1.22)1
                                                                                                               White: 0.48% (0.01, 0.95)1
                                                                                                               Black: 0.13% (-0.87,1.13)1
                                                                                                                          (-1.09,1.27)1
                                                                                                               65-75:-0.46% (-1.42, 0.50)1
                                                                                                               >75: 0.80% (0.27, 1.33)1
    
                                                                                                               Educational Attainment:
                                                                                                               Low (<8yr): 0.07% (-1.44,1.58)1
                                                                                                               Medium (8-12 yr): 0.29% (-0.32, 0.90)1
                                                                                                               High (>12yr): 0.52% (-0.28,1.32)1
    
                                                                                                               Location of Death:
                                                                                                               In hospital: 0.06% (-0.49, 0.61)1
                                                                                                               Out of hospital: 0.87% (0.05,1.69)1
    
                                                                                                               Season:
                                                                                                               Wnter: -0.09% (-0.93, 0.75) 1
                                                                                                               Summer: 0.67% (-0.31,1.65)1
                                                                                                               Transition (spring/fall):
                                                                                                               0.51% (-0.20,1.22)1
    
                                                                                                               Contributing causes of disease: All-
                                                                                                               cause
                                                                                                               Secondary pneumonia present:
                                                                                                               0.67% (0.16, 1.18)1-2avg
                                                                                                               Secondary pneumonia absent:
                                                                                                               0.34% (0.16, 0.52) 1-2 avg
                                                                                                               Secondary heart failure present:
                                                                                                               0.42% (0.01, 0.83) 1-2 avg
                                                                                                               Secondary heart failure absent:
                                                                                                               0.37% (0.19, 0.55) 1-2 avg
                                                                                                               Secondary stroke present:
                                                                                                               0.85% (0.30, 1.40) 1-2 avg
                                                                                                               Secondary stroke absent:
                                                                                                               0.32% (0.14, 0.50) 1-2 avg
                                                                                                               Diabetes present:
                                                                                                               0.57% (0.02, 1.12) 1-2 avg
                                                                                                               Diabetes absent:
                                                                                                               0.34% (0.14, 0.54) 1-2 avg
    
                                                                                                               Respiratory
                                                                                                               Secondary pneumonia present:
                                                                                                               1.28% (-0.33, 2.89)0-3
                                                                                                               Secondary pneumonia absent:
                                                                                                               0.78% (0.15,1.41)0-3
                                                                                                               Secondary heart failure present:
                                                                                                               1.48% (0.07, 2.89)0-3
                                                                                                               Secondary heart failure absent:	
    December 2009                                                    E-341
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                                 0.79% (0.26, 1.32)0-3
                                                                                                                 Secondary stroke present:
                                                                                                                 1.95% (-0.11,4.01) 0-3
                                                                                                                 Secondary stroke absent:
                                                                                                                 0.80% (0.29, 1.31)0-3
                                                                                                                 Diabetes present:
                                                                                                                 1.96% (-0.22, 4.14)0-3
                                                                                                                 Diabetes absent:
                                                                                                                 0.82% (0.31, 1.33) 0-3
    
                                                                                                                 Heart Disease
                                                                                                                 Secondary pneumonia present:
                                                                                                                 0.66% (-0.63, 1.95)2
                                                                                                                 Secondary pneumonia absent:
                                                                                                                 0.49% (0.27, 0.71)2
                                                                                                                 Secondary stroke present:
                                                                                                                 0.73% (-0.05, 1.51)2
                                                                                                                 Secondary stroke absent:
                                                                                                                 0.48% (0.24, 0.72) 2
                                                                                                                 Diabetes present:
                                                                                                                 0.34% (-0.42,1.10)2
                                                                                                                 Diabetes absent: 0
                                                                                                                 .52% (0.28, 0.76) 2
    
                                                                                                                 Myocardial Infarction
                                                                                                                 Secondary pneumonia present:
                                                                                                                 1.54% (-1.05, 4.13)0
                                                                                                                 Secondary pneumonia absent:
                                                                                                                 0.42% (0.05, 0.79) 0
                                                                                                                 Secondary stroke present:
                                                                                                                 0.50% (-1.38, 2.38)0
                                                                                                                 Secondary stroke absent:
                                                                                                                 0.36% (-0.05, 0.77) 0
                                                                                                                 Diabetes present:
                                                                                                                 0.70% (-0.38, 1.78)0
                                                                                                                 Diabetes absent:
                                                                                                                 0.41% (0.04, 0.78)0
    
                                                                                                                 Stroke
                                                                                                                 Secondary pneumonia present:
                                                                                                                 1.74% (0.35, 3.13) 1
                                                                                                                 Secondary pneumonia absent:
                                                                                                                 0.29% (-0.16, 0.74)1
                                                                                                                 Secondary heart failure present:
                                                                                                                 1.01% (-0.77,1.79)1
                                                                                                                 Secondary heart failure absent:
                                                                                                                 0.38% (-0.05, 0.81) 1
                                                                                                                 Diabetes present:
                                                                                                                 1.02% (-0.53, 2.57) 1
                                                                                                                 Diabetes absent:
                                                                                                                 0.37% (-0.08, 0.82) 1	
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                             E-342
    

    -------
    Table E-17. Short-term
    Study
    Reference: Burnett et al. (2004,
    0862471
    
    Period of Study: 1981-1999
    Location: 12 Canadian cities
    
    
    
    
    
    
    
    
    
    
    Reference: Kan et al. (2007, 0912671
    Period of Study: Mar 2004-Dec 2005
    Location: Shanghai, China
    
    
    
    
    
    
    exposure-mortality - PMir>25.
    Design & Methods
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Study Design: Time-series
    
    Statistical Analyses:
    1. Poisson, natural splines
    2. Random effects regression
    model
    Age Groups: All ages
    
    
    
    
    
    Outcome (ICD10): Mortality:
    Total (nonaccidental) (AOO-R99)
    Cardiovascular (IOO-I99)
    Respiratory (JOO-J98)
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    GAM, penalized splines
    Age Groups: All ages
    Concentrations'!
    Pollutant: P1 0-2.5
    
    Averaging Time: 24-h avg
    Mean (SD): 1 1.4
    
    Range (Min, Max): NR
    Co pollutant:
    hif~\
    NU2
    f~\
    U3
    S02
    CO
    PM,o
    PM25
    Note: PM10 measurement
    calculated as the sum of PM25
    and PM10.25 measurements.
    Pollutant: PM^.s
    Averaging Time: 24-h avg
    Mean (SD): 56.4 (1.34)
    Range (Min, Max): (8.3, 235.0)
    Copollutant (correlation):
    PM10:r = 0.88
    
    PM25:r = 0.48
    03:r = 0.07
    Effect Estimates (95% Cl)
    Increment: 10 pg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    1981-1999
    
    PM10.25: 0.31% (-0.66, 1.33)1
    PM10.25+N02: 0.65% (-0.23, 1.59)1
    
    
    
    
    
    
    
    
    Increment: 10 pg/m3
    % Increase (Lower Cl, Upper Cl)
    lag: Total: 0.12% (-0.13, 0.36)
    0-1
    Cardiovascular: 0.34% (-0.05, 0.73)
    
    0-1
    Respiratory: 0.40% (-0.34, 1.13)
    0-1
    Reference: Kettunen et al. (2007,
    0912421
    Period of Study: 1998-2004
    Location: Helsinki, Finland
    Outcome (ICD10): Mortality:
    Stroke (160-161,163-164)
    Study Design: Time-series
    Statistical Analyses: Poisson
    GAM, penalized thin-plate
    splines
    Age Groups: > 65 yr
    Pollutant: PMi0.2.5
    Averaging Time: 24-h avg
    Median (SD) unit: Cold Season:
    6.7
    Warm Season: 8.4
    Range (Min, Max):
    Cold Season: (0.0,101.4)
    Warm Season: (0.0,  42.0)
    Copollutant: 03, CO, N02
    PM10
    PM25
    UFP
    Increment:
    Cold Season: 8.3 pg/m3
    Warm Season: 5.7 pg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    Cold Season: -1.04% (-6.63, 4.89) 0
    -2.49% (-7.57, 2.88)
    1-4.93% (-9.99, 0.41)2
    -4.33% (-9.32, 0.93) 3
    Warm Season: 7.05% (-1.88,16.80) 0
    4.38% (-4.26, 13.81)
    1:-1.19% (-9.45, 7.84)2
    1.42% (-6.79, 10.34)3
    Reference: Klemm et al. (2004,
    0565851
    Period of Study: Aug 1998-Jul 2000
    Location: Fulton and DeKalb counties,
    Georgia (ARIES)
    Outcome: Mortality:
    Nonaccidental (<800)
    Cardiovascular (390-459)
    Respiratory (460-519)
    Cancer (140-239)
    Study Design: Time-series
    Statistical Analyses: Poisson
    GLM, natural cubic splines
    Age Groups: <65 yr, 2 65 yr
    Pollutant: PMi0.25
    Averaging Time: 24-h avg
    Mean (SD): 9.69 (3.94)
    Range (Min, Max): (1.71, 25.17)
    Copollutant: PM25
    03
    N02
    CO
    S02
    Acid
    EC
    OC
    S04
    Oxygenated Hydrocarbons
    Nonmethane hydrocarbons
    N03
    Increment: NR
    P(SE)
    lag:
    Quarterly Knots:
    0.00433 (0.00333) 0-1
    Monthly Knots:
    0.00617(0.00360)0-1
    Biweekly Knots:
    0.00516(0.00381)0-1
    December 2009
                                   E-343
    

    -------
    Study
    Reference: Perez et al. (2008, 1560201
    Period of Study: Mar 2003-Dec 2005
    Location: Barcelona, Spain
    
    
    
    
    
    Reference: Perez et al. (2008, 1560201
    Period of Study: Mar 2003-Dec 2005
    Location: Barcelona, Spain
    
    
    
    
    
    
    
    Reference: Perez et al. (2008, 1560201
    Period of Study: Mar 2003-Dec 2005
    Location: Barcelona, Spain
    
    
    
    
    
    
    Reference: Slaughter et al. (2005,
    0738541
    Period of Study: Jan 1995-Dec 1999
    
    Location: Spokane, Washington
    
    
    
    
    Design & Methods
    Outcome: Respiratory mortality
    Study Design: Cohort
    Covariates: Temperature,
    humidity
    Statistical Analysis:
    autoregressive Poisson
    regression models
    
    Statistical Package: NR
    Age Groups: All deaths
    Outcome:
    Cardiovascular mortality
    Study Design: Cohort
    Covariates: Temperature,
    humidity
    
    Statistical Analysis:
    Autoregressive Poisson
    regression models
    
    Statistical Package: NR
    Age Groups: All deaths
    Outcome:
    Cerebrovascular mortality
    Study Design: Cohort
    Covariates: Temperature,
    humidity
    
    Statistical Analysis:
    Autoregressive Poisson
    regression models
    
    Statistical Package: NR
    Age Groups: All deaths
    Outcome: Mortality:
    Nonaccidental (< 800)
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    GLM, natural splines
    Age Groups: All ages
    
    
    
    Concentrations'!
    Pollutant: PM,O., 5
    Averaging Time: 24 h
    Mean (SD) Unit: 14.0 (9.5)
    pg/m
    Range (Min, Max): 0.1, 93.1
    Copollutant: PM25-1,PM1
    
    
    
    Pollutant: PM,O., 5
    Averaging Time: 24 h
    Mean (SD) Unit: 14.0 (9.5)
    pg/m
    Range (Min, Max): 0.1, 93.1
    
    Copollutant: PM25-1,PM1
    
    
    
    
    Pollutant: PM10., 5
    Averaging Time: 24 h
    Mean (SD) Unit: 14.0 (9.5)
    pg/m3
    Range (Min, Max): 0.1, 93.1
    Copollutant: PM25-1,PM1
    
    
    
    
    Pollutant: PMi0.25
    Averaging Time: 24-h avg
    
    Mean (SD) unit: NR
    Range (9th, 96th): NR
    Copollutant (correlation):
    PM1:r = 0.19
    PM25:r = 0.31
    PM,0:r = 0.94
    CO: r = 0.32
    Effect Estimates (95% Cl)
    Increment: 10 pg/m3
    Odds Ratio (96%CI) Lag
    Single Pollutant Model
    Avg LO-1: 1.000(0.944-1.060), p = 0.991
    L1: 1.002 0.955-1.052), p = 0.931
    L2: 1.070 1.023-1.118), p = 0.003
    Multi-pollutant Model
    Avg LO-1: 1.002 (0.937-1. 071), p = 0.958
    L1 : 0.998 (0.943-1. 056), p = 0.0.936
    L2: 1.033 (0.980-1. 089), p = 0.226
    Increment: 10 pg/m3
    Odds Ratio (96%CI) Lag
    Avg LO-1: 1.054 (1.019-1.089), p = 0.002
    L1: 1.059 (1.031-1.072), p = 0.000
    L2: 1.044 (1.017-1.072), p = 0.001
    
    Multi-pollutant Model
    Avg LO-1: 1.053 (1.013-1.094), p = 0.009
    L1 : 1.059 (1.026-1. 094), p = 0.001
    L2: 1.044 (1.012-1.078), p = 0.007
    
    
    Increment: 10 pg/m3
    Odds Ratio (96%CI) Lag
    Avg LO-1: 1.087 (1.018-1. 161), p = 0.013
    L1: 1.086 1.030-1.145), p = 0.002
    L2: 1.051 0.997-1.108), p = 0.064
    
    Multi-pollutant Model
    Avg LO-1: 1.103(1. 022-1. 191), p = 0.011
    L1: 1.098 (1.030-1. 171), p = 0.004
    L2: 1.076 (1.010-1. 146), p = 0.023
    
    
    This study does not present quantitative results for
    PM,0-2.5.
    
    
    
    
    
    
    
    Reference: Stieb et al. (2002, 0252051
    
    Period of Study:
    Publication dates of studies: 1985-Dec
    2000
    Mortality series: 1958-1999
    
    Location: 40 cities (11 Canadian cities,
    19 U.S. cities, Santiago, Amsterdam,
    Erfurt, 7 Korean cities)
    Outcome: Mortality: All-cause
    (nonaccidental)
    
    Study Design: Meta-analysis
    
    Statistical Analyses: Random
    effects model
    
    Age Groups: All ages
    Pollutant: PMi0.25
    
    Averaging Time: NR
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant:
    Varied between studies:
    PM25,03, S02, N02, CO
    Increment: 13.0 pg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    
    Single-pollutant models: 10 studies
    
    PMi0.25:1.2%(0.5, 1.9)
    
    Multipollutant models: 6 studies
    
    PM10.25: 0.9% (-0.3, 2.0)
    December 2009
                                    E-344
    

    -------
                  Study
        Design & Methods
         Concentrations!
             Effect Estimates (95%  Cl)
    Reference: Villeneuve et al. (2003,
    0550511
    
    Period of Study: 1986-1999
    
    Location: Vancouver, Canada
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Cardiovascular (401-440)
    
    Respiratory (460-519)
    
    Cancer (140-239)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson,
    natural splines
    
    Age Groups: 2 65
    Pollutant: PMi0.2.5
    
    Averaging Time: 24-h avg
    Mean (SD):
    Daily: 6.1
    Every 6th Day
    8.3
    
    Range (Min, Max):
    Daily: (0.0, 72.0)
    Every 6th Day: (0.7, 35.0)
    
    Co pollutant:
    PM25
    PM10
    S02
    CO
    N02
    03
    Increment: 11.0|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Nonaccidental
    1.4% (-2.5, 5.4) 0-2 avg
    1.0% (-1.9, 4.0)0
    -1.1% (-4.0, 1.8)1
    2.0% (-1.0, 5.1)2
    
    Cardiovascular
    5.9% (-0.2, 12.4) 0-2 avg
    5.9%  1.1,  10.8)0
    1.4%  -3.3,6.4)1
    2.2% (-2.0, 6.7) 2
    
    Respiratory
    -1.0% (-9.8, 8.8) 0-2 avg
    -1.5% (-9.4, 7.1  "
    -1.5% (-8.4, 6.0
    0.1% (-6.4, 6.9)2
    
    Cancer
    4.4% (-3.6, 13.1) 0-2 avg
    3.1% (-2.9, 9.4)0
    -1.0% (-6.9, 5.3)1
    4.0% (-2.1, 10.4) 2
    Reference: Wilson et al. (2007,
    1571491
    
    Period of Study: 1995-1997
    
    Location: Phoenix, Arizona
    Outcome: Mortality:
    
    Cardiovascular
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson
    GAM, nonparametric smoothing
    spline
    
    Age Groups:  >25
    Pollutant: PM10.25
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 10 pg/m
    
    % Excess Risk (Lower Cl, Upper Cl) lag:
    Central Phoenix:
    2.4% (-1.2, 6.1)0-5 ma
    
    Middle Phoenix:
                                                                                                    3.8%
                                                                                                    3.4%
          0.3, 7.5) 0-5 ma
          1.0,5.8)1
                                                                                                    3.0% (0.7, 5.4) 2
    
                                                                                                    Outer Phoenix:
                                                                                                    1.6% (-1.9, 5.2) 0-5 ma
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                                    E-345
    

    -------
    Table  E-18.    Short-term exposure-mortality • PM2.5 (including PM  components/sources).
                 Study
    Design & Methods
                                                                                Concentrations!
    Effect Estimates (95% Cl)
    Reference: Basu et al. (2008, 0987161  Outcome (ICD10): Mortality:
    
    Period of Study: May 1999-Sept 2003  Nonaccidental (V01-Y98)
    Location: 9 California counties
                                      Study Design:
                                      (1) Main analysis: Case-crossover
    
                                      (2) Sensitivity analysis: Time-series
    
                                      Statistical Analyses:
    
                                      (1) Main analysis: conditional logistic
                                      regression
    
                                      (2) Sensitivity analysis: Poisson GAM
    
                                      Age Groups: All ages
                               Pollutant: PM25
    
                               Averaging Time: 24-h avg
                               Mean (SE) unit:
                               Contra Costa: 8.6
                               Fresno: 7.6
                               Kern: 11.3
                               Los Angeles: 19.8
                               Orange: 17.0
                               Riverside: 28.4
                               Sacramento: 8.8
                               San Diego: 13.4
                               Santa Clara: 10.8
                               IQR (25th, 75th):
                               Contra Costa: (5.8,10.1)
                               Fresno: (3.8, 9.8)
                               Kern: (8.0,13.5)
                               Los Angeles: (14.7, 23.3)
                               Orange: (11.8, 21.0)
                               Riverside: (17.9, 36.1)
                               Sacramento: (5.8,10.1)
                               San Diego: (10.3,15.8)
                               Santa Clara: (7.2,13.8)
    
                               Copollutant (correlation):
                               PM,or = 0.45
                                                                                                           The study does not provide results
                                                                                                           quantitatively.
    
    
    
    
    Reference: Dominici et al. (2007,
    097361)
    
    Period of Study:
    PM,0: 1987-2000
    DM • IQQQ onnn
    rivi25. iyyy-zuuu
    Location: 100 U.S. counties
    (NMMAPS)
    
    Reference: Dominici et al. (2007,
    0991351
    Period of Study: 2000-2005
    Location: 72 U.S. counties
    representing 69 communities
    
    Reference: Franklin et al. (2007,
    0912571
    
    Period of Study: 1997-2002
    Location: 27 U.S. communities
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Mortality:
    All-cause (nonaccidental)
    Cardiorespiratory
    Other-cause
    Study Design: Time-series
    Statistical Analyses: 2-stage Bayesian
    hierarchical model
    Age Groups: All ages
    Outcome: Total mortality
    Study Design: Time-series
    Statistical Analyses: 2-stage Bayesian
    hierarchical model
    Age Groups: All ages
    
    Outcome: Mortality:
    
    All-cause (nonaccidental (<800)
    Cardiovascular (390-429)
    Respiratory (460-51 9)
    
    Stroke (430-438)
    Study Design: Time-stratified case-
    crossover
    Statistical Analyses: Conditional
    logistic regression
    Age Groups: All ages
    
    
    
    
    
    
    03 1hr r = 0.28
    03 8hr r = 0.22
    CO r = 0.45
    N02r = 0.43
    Pollutant: PM25
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (Min, Max): NR
    Copollutant (correlation): NR
    
    Pollutant: PM25, Nickel, speciated fine
    PM and Vanadium
    Averaging Time: Annual avg
    Mean (SD): NR
    Range (Min, Max): NR
    Copollutant (correlation): NR
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    Mean (SD): 15.7 pg/m3
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Increment: 10|jg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    1999-2000:
    All-cause: 0.29% (0.01, 0.57)1
    Cardiorespiratory: 0.38% (-0.07, 0.82) 1
    
    The study does not provide results
    quantitatively.
    Note: The study investigated whether
    county-specific short-term effects of
    PM10 on mortality are modified by long-
    term county-specific nickel or vanadium
    PM2 5 concentrations.
    
    Increment: 10|jg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    All-cause (nonaccidental):
    0.67% (-0.12, 1.46)0
    1.21% (0.29, 2.14)
    10.82% (0.02, 1.63)0-1
    
    Respiratory:
    1.31% (-0.10, 2.73)0
    1.78% (0.20, 3.36) 1
    1.67% (0.19, 3.16)0-1
    Cardiovascular:
    0.34% (-0.61, 1.28 0
    0.94% (-0.14, 2.02 1.
    0.54% (-0.47, 1.54)0-1
    Stroke:
    0.62% (-0.69, 1.94)0
    1.03% (0.02, 2.04)1.
    0.67% (-0.23, 1.57)0-1
    December 2009
                            E-346
    

    -------
                  Study                        Design & Methods                 Concentrations!              Effect Estimates (95% Cl)
    
    
                                                                                                                   Age> 75:
                                                                                                                   All cause: 1.66% (0.62, 2.70)1
                                                                                                                   Respiratory: 1.85% (0.27, 3.44) 1
                                                                                                                   Cardiovascular: 1.29% (0.15, 2.42) 1
                                                                                                                   Stroke: 1.52% (0.37, 2.67)1
    
                                                                                                                   Age<75:
                                                                                                                   All cause: 0.62% (-0.30,1.55)1
                                                                                                                   Respiratory: 1.53% (-0.67, 3.74) 1
                                                                                                                   Cardiovascular: 0.26% (-1.04,1.56) 1
                                                                                                                   Stroke: -0.78% (-2.32, 0.76) 1
    
                                                                                                                   Male:
                                                                                                                   All cause: 1.06% (0.07, 2.06)1
                                                                                                                   Respiratory: 1.90% (0.14, 3.65)1
                                                                                                                   Cardiovascular: 0.52% (-0.63,1.66) 1
                                                                                                                   Stroke: 0.79% (-0.42, 2.02) 1
    
                                                                                                                   Female:
                                                                                                                   All cause: 1.34% (0.40, 2.27)1
                                                                                                                   Respiratory: 1.57% (-0.22, 3.35) 1
                                                                                                                   Cardiovascular: 1.30% (0.14, 2.46) 1
                                                                                                                   Stroke: 0.79% (-0.51, 2.09)1
    
                                                                                                                   East:
                                                                                                                   II cause: 1.95% (0.50, 3.40)1
                                                                                                                   Respiratory: 2.66% (0.33, 5.00) 1
                                                                                                                   Cardiovascular: 1.52% (0.06, 2.98) 1
                                                                                                                   Stroke: 1.16% (-0.40, 2.73)1
    
                                                                                                                   V\fest:
                                                                                                                   All cause: 0.05% (-1.80,1.89)1
                                                                                                                   Respiratory: 0.67% (-2.00, 3.34)11
                                                                                                                   Cardiovascular: 0.11% (-2.03, 2.24) 1|
                                                                                                                   Stroke: 0.94% (-0.38, 2.26) 1
    
                                                                                                                   PM25>15|jg/m3:
                                                                                                                   All cause: 1.10% (-0.43, 2.64)1
                                                                                                                   Respiratory: 1.42% (-0.84, 3.68) 1
                                                                                                                   Cardiovascular: 0.88% (-0.87, 2.62) 1
                                                                                                                   Stroke: 0.91% (-0.28, 2.10)1
    
                                                                                                                   PM25<15|jg/m3:
                                                                                                                   All cause: 1.41% (-0.49, 3.30)1
                                                                                                                   Respiratory: 2.46% (-0.49, 5.42) 1
                                                                                                                   Cardiovascular: 1.09% (-1.15, 3.32) 1
                                                                                                                   Stroke: 1.36% (-0.56, 3.27)1
    
                                                                                                                   Effect of A/C at percentile of air
                                                                                                                   conditioning prevalence:
                                                                                                                   25th percentile (45% prevalence of
                                                                                                                   A/C):
                                                                                                                   All cause: 1.50% (0.13, 2.88)1
                                                                                                                   Respiratory: 2.27% (0.27, 4.27) 1
                                                                                                                   Cardiovascular: 1.04% (-0.54, 2.63) 1
                                                                                                                   Stroke: 1.04% (-0.44, 2.53)1
    
                                                                                                                   75th percentile (80% prevalence of
                                                                                                                   A/C):
                                                                                                                   All cause: 0.85% (-0.64, 2.35) 1
                                                                                                                   Respiratory: 1.04% (-1.29, 3.37)1
                                                                                                                   Cardiovascular: 0.81% (-0.93, 2.61) 1
                                                                                                                   Stroke: 1.03% (-0.76, 2.83)1
    
                                                                                                                   Effect of A/C at percentile of air
                                                                                                                   conditioning prevalence in cities with
                                                                                                                   summer peaking PM25 concentrations:
                                                                                                                   25th percentile (45% prevalence of
                                                                                                                   A/C):
                                                                                                                   All cause: 1.01% (-0.30, 2.32)1
                                                                                                                   Respiratory: 0.76% (-1.38, 2.90)1
                                                                                                                   Cardiovascular: 0.43% (-0.86,1.72) 1
                                                                                                                   Stroke:-0.18% (-2.08,1.73)1
    
                                                                                                                   75th percentile (77% prevalence of
                                                                                                                   A/C):
                 	All cause:-0.55% (-1.95, 0.85)1
    December 2009                                                     E-347
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
                                                                                                               Respiratory: -2.08% (-4.47, 0.31) 1
                                                                                                               Cardiovascular: -1.02% (-2.44, 0.41) 1
                                                                                                               Stroke: 0.69% (-1.19" 2.57)1	
    Reference: Franklin et al. (2008,
    0974261
    
    Period of Study: 2000-2005
    
    Location: 25 U.S. communities
    Outcome (ICD10): Mortality:
    
    Nonaccidental (V01-Y98)
    
    Respiratory (JOO-J99)
    
    Cardiovascular (101-152)
    
    Stroke (I60-J69)
    
    Study Design: Time-series
    
    Statistical Analyses:
    
    1st stage: Poisson, cubic spline
    
    2nd stage: Random effects meta-
    analysis
    
    Age Groups: All ages
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Range Mean (SD):
    
    Winter: 9.6-34.4
    
    Spring: 6.7-27.6
    
    Summer: 7.6-26.0
    
    Fall: 9.5-32.1
    
    Range (Min, Max): NR
    
    Copollutant:
    Al, As, Br, Cr, EC, Fe, K, Mn, Na*, Ni,
    N03", NH4i OC, Pb, Si, S042", V, Zn
    Increment: 10|jg/rrf
    % Increase (Lower Cl, Upper Cl) lag:
    
    Nonaccidental: 0.74% (0.41,1.07) 0-1
    Cardiovascular: 0.47% (0.02, 0.92) 0-1
    Respiratory: 1.01% (-0.03, 2.05) 1-2
    Stroke: 0.68% (-0.21,1.57) 0-1
    Winter: 0.15% (-0.42, 0.72)0-1
    Spring: 1.88% (1.29, 2.48)0-1
    Summer: 0.99% (0.35,1.68)0-1
    Fall: 0.19% (-0.25, 0.64)0-1
    West: 0.51% (0.10, 0.92)0-1
    
    Easts Central:
    0.92% (0.44, 1.39)0-1
    
    % Increase per 10 pg/m3 increase in
    PM25 for an IQR increase in species to
    PM25 mass proportion
    Univariate analysis
    Al: 0.58%
    As: 0.55%
    Br: 0.38
    Cr: 0.33%
    EC: 0.06%
    Fe:0.12%
    K:0.41%
    Mn:0.14%
    Na+: 0.20%
    Ni: 0.37%
    N0r:  -0.49%
    NH4: 0.04%
    OC: -0.02%
    Pb:0.17%
    Si: 0.41%
    S042":0.51%
    V: 0.30%
    Zn: 0.23%
    Multivariate(l)
    Al: 0.79%
    Ni: 0.34%
    S042": 0.75%
    Multivariate (2)
    Al:0.61%
    Ni: 0.35%
    As: 0.58%
    Reference: Holloman et al. (2004,
    0873751
    
    Period of Study: 1999-2001
    
    Location: 7 North Carolina counties
    Outcome (ICD10): Mortality:
    
    Cardiovascular (IOO-I99)
    
    Study Design: Time-series
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
                                       Statistical Analyses: 3-stage Bayesian  Range (Min, Max): NR
                                       hierarchical model
                                                                           Copollutant (correlation): NR
                                       Age Groups: >16
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl)
    
    lag:
    
    2.5% (-3.9 to 9.6)
    
    0
    
    4.0% (-3.3 to 12.2)
    
    1
    
    11.4% (2.8-19.8)
    
    2
    
    -1.1% (-7.5 to 5.2)
    
    3
    December 2009
                                    E-348
    

    -------
    Study
    Reference: Hopke et al. (2006,
    088390)
    
    Period of Study: Washington, DC: Aug
    1988-Dec 1997. Phoenix, Arizona: Mar
    1995-Jun 1998
    Location: Washington, DC and
    surrounding counties
    Phoenix, Arizona
    
    
    
    
    
    
    
    
    
    
    
    Reference: Ito et al. (2006, 0883911
    Period of Study: Aug 1988-Dec 1997
    Location: Washington, DC and
    surrounding counties
    
    
    
    
    Design & Methods
    Outcome: Mortality:
    Total (nonaccidental)
    Cardiovascular
    Cardiovascular-Respiratory
    Study Design: Source-apportionment
    Statistical Analyses: Receptor
    modeling
    
    Age Groups: All ages
    
    
    
    
    
    
    
    
    
    Outcome: Mortality:
    Total (nonaccidental)
    Cardiovascular
    Cardiovascular-Respiratory
    Study Design: Time-series
    Source-apportionment
    Statistical Analyses: Poisson GLM,
    natural splines
    Age Groups: All ages
    
    
    Concentrations!
    Pollutant:
    Source-apportioned PM25:
    Washington, DC: Soil
    Traffic
    Secondary Sulfate
    Nitrate
    Residual Oil
    Wood Smoke
    Sea Salt
    Incinerator
    Primary Coal
    Phoenix, Arizona: Crustal
    Traffic
    Vegetation and Wood Burning
    Secondary Sulfate
    Metals
    Sea Salt
    Primary Coal
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (Min, Max): NR
    Copollutant (correlation): NR
    Pollutant:
    Source-apportioned PM25:
    Soil
    Traffic
    Secondary Sulfate
    Nitrate
    Residual Oil
    Wood Smoke
    Sea Salt
    Incinerator
    Primary Coal
    Averaging Time: 24-h avg
    Mean (SD): 17.8 (8.7)
    Range (Min, Max): NR
    Copollutant (correlation): NR
    Effect Estimates (95% Cl)
    The study does not present quantitative
    results
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Increment:
    PM25 = 28.7|jg/m3
    PM25 Sources 5-95th = Not reported
    % Increase (Lower Cl, Upper Cl) lag:
    Secondary sulfate (variance-weighted
    mean percent excess mortality)
    6.7% (1.7, 11.7)3
    Primary coal-related PM2 5 (mean
    percent excess mortality)
    5.0% (1.0, 9.1)3
    Residual oil (mean percent excess
    mortality)
    2.7% (-1.1, 6.5) 2
    
                                                                                                                Traffic-related PM25 (mean percent
                                                                                                                excess mortality)
                                                                                                                2.6% (-1.6, 6.9) NR
                                                                                                                Soil-related PM25 (mean percent
                                                                                                                excess mortality)
                                                                                                                2.1% (-0.8, 4.9) NR
                                                                                                                PMz; Sensitivity analysis:
                                                                                                                2 df/yr: 7.9% (3.3,12.6)3
                                                                                                                4 df/yr: 8.3% (3.7,13.1)3
                                                                                                                8 df/yr: 8.3% (3.7,13.2)3
                                                                                                                16 df/yr: 8.1% (3.1,13.2) 3
    Reference: Kan et al. (2007, 0912671
    Period of Study: Mar 2004-Dec 2005
    Location: Shanghai, China
    Outcome (ICD10): Mortality:
    Total (nonaccidental) (AOO-R99)
    Cardiovascular (IOO-I99)
    Respiratory (JOO-J98)
    Study Design: Time-series
    Statistical Analyses: Poisson GAM,
    penalized splines
    Age Groups: All ages
    Pollutant: PM25
    Averaging Time: 24-h avg
    Mean (SD): 52.3 (1.57)
    Range (Min, Max): (2.0, 330.3)
    Copollutant (correlation):
    PM10:r = 0.84
    PMi0.25:r = 0.48
    03:r = 0.31
    Increment: 10|jg/m
    % Increase (Lower Cl, Upper Cl)
    lag:
    Total: 0.36% (0.11, 0.61) 0-1
    Cardiovascular: 0.41% (0.01, 0.82) 0-1
    Respiratory: 0.95% (0.16,1.73)0-1
    December 2009
                                    E-349
    

    -------
    Study
    Reference: Kettunen et al. (2007,
    0912421
    
    Period of Study: 1998-2004
    Location: Helsinki, Finland
    
    
    
    
    
    
    
    Reference: Klemm et al. (2004,
    0565851
    
    Period of Study: Aug 1998-Jul 2000
    Location: Fulton and DeKalb counties,
    Georgia (ARIES)
    
    
    
    
    
    
    
    
    
    
    Reference: Lippmann et al. (2006,
    0911651
    
    Period of Study: 2000-2003
    Location: 60 U.S. cities (NMMAPS)
    
    Reference: Mar et al. (2005, 0875661
    Period of Study: 1995-1997
    
    Location: Phoenix, Arizona
    
    
    
    
    
    
    Design & Methods
    Outcome (ICD10): Mortality:
    
    Stroke (160-161, 163-I64)
    Study Design: Time-series
    Statistical Analyses: Poisson GAM,
    penalized thin-plate splines
    Age Groups: > 65
    
    
    
    
    
    
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Cardiovascular (390-459)
    
    Respiratory (460-51 9)
    Cancer (140-239)
    Study Design: Time-series
    Statistical Analyses: Poisson GLM,
    natural cubic splines
    
    Age Groups: <65
    >65
    
    
    
    
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Study Design: Time-series
    Statistical Analyses: Poisson GLM
    Age Groups: All ages
    Outcome: Mortality:
    Nonaccidental (<800)
    
    Cardiovascular (390-448)
    Study Design: Time-series
    Statistical Analyses: Poisson GLM
    Age Groups: 2 65
    
    
    
    
    Concentrations!
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    Median (SD) unit:
    Cold Season: 8.2
    \Narm Season: 7.8
    Range (Min, Max):
    Cold Season: (1.1, 69.5)
    Warm Season: (1.1, 41.5)
    Copollutant:
    03
    CO
    N02
    PM,o
    PM,0-2.5
    UFP
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    Mean (SD): 19.62 (8.32)
    
    Range (Min, Max): (5.29, 48.01)
    Copollutant:
    PM,0-2.5
    03
    N02
    CO
    S02
    Acid
    EC
    OC
    S04
    Oxygenated Hydrocarbons
    Nonmethane hydrocarbons
    N03
    Pollutant: Speciated Fine PM:
    Al, Ar, Cr, Cu, EC, Fe, Mn, Ni, Nitrate,
    OC, Pb, Se, Si, Sulfate, V, Zn
    Averaging Time: Annual avg
    Mean (SD): R
    Range (Min, Max): NR
    Pollutant:
    Source-apportioned PM25:
    Soil
    Traffic
    Secondary Sulfate
    Nitrate
    Residual Oil
    V\food Smoke
    Sea Salt
    Incinerator
    Primary Coal
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (Min, Max): NR
    Effect Estimates (95% Cl)
    Increment:
    Cold Season: 6.7 pg/m3
    \Narn Season: 5.7 pg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    Cold Season
    -0.19% (-3.77, 3.51)0
    -0.17% (-3.73, 3.52)1
    0.59% (-2.95, 4.26 2
    0.46% (-3. 10, 4.15 3
    \Narm Season
    6.86% (0.37, 13.78)0
    7.40% (1.33, 13.84)1
    4.01% (-1.79, 10.14)2
    -1.72% (-7.38, 4.29)3
    
    Increment: NR
    
    p(SE)lag:
    Quarterly Knots:
    
    PM25: 0.00398 (0.00161)
    0-1
    Monthly Knots:
    PM25: 0.00544 (0.00184)
    
    0-1
    Biweekly Knots:
    PM25: 0.00369 (0.00201)
    
    0-1
    
    The study does not present quantitative
    results.
    
    
    
    Increment: PM2 5 Sources 5-95th = NR
    % Increase (median percent excess
    risk) lag:
    
    Secondary sulfate: 16.0% 0
    Traffic: 13.2% 1
    Copper (Cu) smelter: 12.0%0
    Sea salt: 10.2% 5
    Biomass/wood combustion: 8.6% 3
    
    
    December 2009
    E-350
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Ostro et al. (2006, 0879911
    
    Period of Study: Jan 1999-Dec 2002
    
    Location: 9 California counties
    (CALFINE)
    Outcome (ICD10): Mortality:
    
    Total mortality (respiratory,
    cardiovascular, ischemic heart disease,
    diabetes)
    
    Respiratory (JOO-J98)
    
    Cardiovascular (IOO-I99)
    
    Ischemic heart disease (I20-I25)
    
    Diabetes (E10-E14)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson, natural
    splines and penalized splines
    
    Age Groups: All ages
    
    >65yr
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    Mean (SD):
    Contra Costa: 14
    Fresno: 23
    Kern: 22
    Los Angeles: 21
    Orange: 21
    Riverside: 29
    Sacramento: 14
    Santa Clara: 15
    San Diego: 16
    
    Range (Min, Max):
    Contra Costa: (1,77)
    Fresno: (1,160)
    Kern: (1,155)
    Los Angeles: (4, 85)
    Orange: (4,114)
    Riverside: (2,120)
    Sacramento: (1,108)
    Santa Clara: (2, 74)
    San Diego: (0, 66)
    
    Copollutant (correlation):
    N02 r = 0.56
    CO  r = 0.60
    03(1h)  r = -0.14
    03(8h)  r = -0.22
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl) lag:
    Penalized splines
    All ages:
    All-cause:
    0.2% (-0.2, 0.7) 2
    0.6% (0.2, 1.0)0-1
    
    Cardiovascular:
    0.3% (-0.1, 0.7) 2
    0.6% (0.0, 1.1)0-1
    
    Respiratory:
                                                                                                                  1.3%
                                                                                                                  2.2%
          0.1,2.6)2
          0.6, 3.9) 0-1
                                                                                                                  >65:
                                                                                                                  All-cause:
                                                                                                                  0.2% (-0.2, 0.7) 2
                                                                                                                  0.7% (0.2, 1.1)0-1
    
                                                                                                                  Ischemic heart disease:
                                                                                                                  0.3% (-0.5, 1.0)0-1
                                                                                                                  Males: 0.5% (-0.2,1.2)0-1
                                                                                                                  Females: 0.8%  (0.3,1.3)0-1
                                                                                                                  Whites: 0.8% (0.2,1.3)0-1
                                                                                                                  Blacks: 0.1% (-0.9,1.2)0-1
                                                                                                                  Hispanics:0.8%(-0.1,1.6)0-1
                                                                                                                  In hospital: 0.6% (-0.1,1.3)0-1
                                                                                                                  Out of hospital:  0.6% (0.1,1.1)0-1
                                                                                                                  High school graduates:
                                                                                                                  0.4% (0.0, 0.8) 0-1
                                                                                                                  Non-high school graduates:
                                                                                                                  0.9% (-0.1,1.9) 0-1
    
                                                                                                                  Natural splines
                                                                                                                  All cause
                                                                                                                  4 df: 0.5% (-0.1,1.1)0-1
                                                                                                                  8 df: 0.4% (-0.1, 0.9) 0-1
                                                                                                                  12 df: 0.3% (-0.1, 0.7) 0-1
    
                                                                                                                  Cardiovascular
                                                                                                                  4 df: 0.4% (-0.2, 0.9) 0-1
                                                                                                                  8 df: 0.1% (-0.5, 0.6)0-1
                                                                                                                  12 df: 0.0% (-0.6, 0.6) 0-1
    
                                                                                                                  Respiratory
                                                                                                                  4 df: 2.1% (0.2,  4.1)0-1
                                                                                                                  8 df: 1.6% (-0.5, 3.6)0-1
                                                                                                                  12 df: 1.3% (-0.3, 2.9)0-1
    
                                                                                                                  >65
                                                                                                                  All cause
                                                                                                                  4 df: 0.7% (0.0,  1.3)0-1
                                                                                                                  8 df: 0.4% (-0.1, 0.9) 0-1
                                                                                                                  12 df: 0.3% (-0.1, 0.8) 0-1	
    December 2009
                                     E-351
    

    -------
    Study
    Reference: Ostro et al. (2007, 0913541
    Period of Study: PM2 5 speciation
    analysis: Jan 2000-Dec 2003. PM25
    analysis: Jan 1999-Dec 2003
    Location: 6 California counties
    (2000-2003). 9 California counties
    (1999-2003) (CALFINE)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Ostro et al. (2008, 0979711
    Period of Study: Jan 2000-Dec 2003
    Location: 6 California counties
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Perez et al. (2008, 1560201
    Period of Study: Mar 2003-Dec 2005
    Location: Barcelona, Spain
    Design & Methods
    Outcome (ICD10): Mortality:
    Total (nonaccidental) mortality
    Respiratory (JOO-J98)
    Cardiovascular (IOO-I99)
    Study Design: Time-series
    Statistical Analyses: Poisson, natural
    splines
    Age Groups: >65
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome (ICD10): Mortality:
    Cardiovascular (IOO-I99)
    Study Design: Time-series
    Statistical Analyses: Poisson, natural
    cubic splines and natural splines
    Age Groups:
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Respiratory mortality
    Study Design: Cohort
    Covariates: Temperature, humidity
    Statistical Analysis: Autoregressive
    Poisson regression models
    Concentrations!
    Pollutant: PM25
    Averaging Time: 24-h avg
    Mean (SD):
    2000-2003: 19.28
    1999-2003: 18.6
    Range (Min, Max): NR
    Copollutant (correlation):
    EC: r = 0.53
    OC:r = 0.62
    N03:r = 0.65
    S04:r = 0.32
    Al:r = 0.02
    Br: r = 0.54
    Ca:r = 0.23
    Cl:r=0.15
    Cu:r = 0.23
    Fe:r = 0.38
    K:r = 0.52
    Mn:r = 0.21
    Ni:r = 0.11
    Pb:r = 0.27
    S:r = 0.35
    Si:r = 0.16
    Ti:r = 0.24
    V:r = 0.20
    Zn:r = 0.51
    Pollutant: PM25, EC, OC, N03, S04,
    Ca, Cl, Cu, Fe, K, S, Si, Ti, Zn
    Averaging Time: 24-h avg
    Mean (SD):
    PM25: 19.28
    EC: 0.966
    OC:7.129
    N03: 5.415
    S04: 1.908
    Ca: 0.080
    Cl: 0.094
    Cu: 0.007
    Fe:0.124
    K: 0.117
    S: 0.648
    Si: 0.168
    Ti: 0.009
    Zn: 0.012
    Range (96th): PM25: 46.91
    EC: 2.57
    OC: 15.91
    N03: 17.46
    S04:5.18
    Ca: 0.20
    Cl: 0.41
    Cu: 0.02
    Fe: 0.34
    K: 0.26
    S:1.70
    Si: 0.43
    Ti: 0.02
    Zn: 0.04
    Pollutant: PM25-i
    Averaging Time: 24 h
    Mean (SD) Unit: 5.5 (3.8) pg/m3
    Range (Min, Max): 0.6, 45.5
    Copollutant: PM10.2.5, PM,
    Effect Estimates (95% Cl)
    Increment: 14.6 pg/m3
    % Increase (Lower Cl, Upper Cl)
    lag:
    Cardiovascular
    1.6% (0.0, 3.1)
    3
    Notes: The study does not present all
    estimates quantitatively.
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    The study does not present quantitative
    results.
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Increment: 10|jg/m3
    Odds Ratio (96%CI) lag
    Avg 10-1:0.998 (0.849-1. 174),
    p = 0.981
    L1: 1.014 (0.886-1. 161), p = 0.838
    12:1.295(1.141-1.470), p = 0.000
                                       Statistical Package: NR
    
                                       Age Groups: All deaths
                                             Iti-pollutant Model
                                          Avg 10-1:0.987 (0.806-1.208),
                                          p = 0.898
                                          11:1.022(0.859-1.214),  p = 0.
                                          12:1.206(1.028-1.416),  p = 0.022
    December 2009
    E-352
    

    -------
    Study
    Reference: Perez et al. (2008, 1560201
    Period of Study: Mar 2003-Dec 2005
    Location: Barcelona, Spain
    
    
    
    
    
    Reference: Perez et al. (2008, 1560201
    Period of Study: Mar 2003-Dec 2005
    Location: Barcelona, Spain
    
    
    
    
    
    
    Reference: Rainham et al. (2005,
    0886761
    
    Period of Study: 1981-1999
    Location: Toronto Canada
    
    
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Cardiovascular mortality
    Study Design: Cohort
    Covariates: Temperature, humidity
    Statistical Analysis: Autoregressive
    Poisson regression models
    Statistical Package: NR
    Age Groups: All deaths
    
    
    Outcome: Cerebrovascular mortality
    Study Design: Cohort
    Covariates: Temperature, humidity
    Statistical Analysis: Autoregressive
    Poisson regression models
    Statistical Package: NR
    Age Groups: All deaths
    
    
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    Cardiorespiratory (390-459
    
    480-519)
    
    Other-causes
    Study Design: Time-series
    Statistical Analyses: Poisson GLM,
    natural splines
    Age Groups: All ages
    
    
    
    
    
    Concentrations!
    Pollutant: PM25.i
    Averaging Time: 24 h
    Mean (SD) Unit: 5.5 (3.8) pg/m3
    Range (Min, Max): 0.6, 45.5
    Copollutant: PM10.2.5, PM,
    
    
    
    
    Pollutant: PM2.5.,
    Averaging Time: 24 h
    Mean (SD) Unit: 5.5 (3.8) pg/m3
    Range (Min, Max): 0.6, 45.5
    Copollutant: PM10.2.5, PM,
    
    
    
    
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    Mean (SD):
    
    All yr: 17.0 (8.7)
    
    Winters (Dec-Feb): 17.2 (6.8)
    Summers (Jun-Aug): 18.8 (10.2)
    Range (Min, Max): NR
    Copollutant:
    
    CO
    N02
    S02
    
    03
    Effect Estimates (95% Cl)
    Increment: 10|jg/m3
    Odds Ratio (96%CI) lag
    Avg 10-1:1.100 (1.002-1.207),
    p = 0.046
    11:1.112(1.031-1.200), p = 0.006
    12:1.078(0.999-1.163), p = 0.052
    Multi-pollutant Model
    Avg 10-1:0.994 (0.885-1. 116),
    p = 0.920
    L1:0.984 0.892-1.086), p = 0.754
    L2: 0.981 0.891-1.079), p = 0.688
    Increment: 10|jg/m3
    Odds Ratio (96%CI) lag
    Avg 10-1:1.083 (0.897-1.307),
    p = 0.406
    L1: 1.121 0.964-1.303), p = 0.140
    L2:0.984 0.841-1.152), p = 0.839
    Multi-pollutant Model
    Avg 10-1:0.899 (0.712-1. 135),
    p = 0.371
    L1: 0.905 0.743-1.102), p = 0.321
    L2:0.868 0.711-1.060), p = 0.165
    Increment: NR
    
    % Increase (Lower Cl, Upper Cl) lag:
    Winter and Wnter Synoptic Events
    \A/]ni.r
    winter
    Total: 0.998% (0.997, 1.000)2
    Cardiorespiratory:
    0.998(0.996,1.000)2
    Other: 0.998% (0.996, 1.000)2
    Dry Moderate
    Total: 1.001% (0.996, 1.007)1
    Cardiorespiratory:
    1.005(0.998,1.011)1
    Other: 0.997% (0.989, 1.006)0
    Dry Polar
    Total: 0.998% (0.995, 1.001)2
    Cardiorespiratory:
    0.995(0.991,0.999)2
                                                                                                               Other: 1.002% (0.998,1.005)1
    
                                                                                                               Moist Moderate
                                                                                                               Total: 0.998% (0.993, 1.002)2
                                                                                                               Cardiorespiratory:
                                                                                                               1.003(0.995,1.010)1
                                                                                                               Other: 0.997% (0.991,1.004)1
    
                                                                                                               Moist Polar
                                                                                                               Total: 1.001% (0.998, 1.005)1
                                                                                                               Cardiorespiratory:
                                                                                                               1.002(0.997,1.007)2
                                                                                                               Other: 1.003% (0.999,1.007)0
    
                                                                                                               Moist Tropical
                                                                                                               Total: 1.007% (0.965, 1.203)0
                                                                                                               Cardiorespiratory:
                                                                                                               1.123(1.031,1.224)2
                                                                                                               Other: 1.248% (1.123, 1.387)0
    
                                                                                                               Transition
                                                                                                               Total: 1.003% (0.996, 1.009)1
                                                                                                               Cardiorespiratory:
                                                                                                               0.996(0.987,1.004)0
                                                                                                               Other: 0.997% (0.990, 1.004)0
    
                                                                                                               Summer and summer Synoptic Events
                                                                                                               Summer
                                                                                                               Total: 1.000% (1.000,1.001)0
                                                                                                               Cardiorespiratory:
                                                                                                               1.001 (1.000,  1.002)0	
    December 2009
    E-353
    

    -------
                  Study                       Design & Methods                 Concentrations!             Effect Estimates (95% Cl)
    
                                                                                                               Other: 1.001% (1.000,1.002)0
    
                                                                                                               Dry Moderate
                                                                                                               Total: 1.001% (0.999, 1.002)2
                                                                                                               Cardiorespiratory:
                                                                                                               1.002(0.999,1.004)2
                                                                                                               Other: 0.999% (0.997, 1.002)0
    
                                                                                                               Dry Polar
                                                                                                               Total: 1.002% (0.999, 1.005)2
                                                                                                               Cardiorespiratory:
                                                                                                               0.996(0.991,1.000)0
                                                                                                               Other: 1.003% (0.999, 1.007)2
    
                                                                                                               Dry Tropical
                                                                                                               Total: 1.016% (1.006, 1.027)0
                                                                                                               Cardiorespiratory:
                                                                                                               1.017(1.005,1.030)2
                                                                                                               Other: 1.017% (1.003,1.031)0
    
                                                                                                               Moist Moderate
                                                                                                               Total: 1.002% (1.000, 1.004)2
                                                                                                               Cardiorespiratory:
                                                                                                               1.003(0.999,1.006)2
                                                                                                               Other: 1.004% (1.001,1.006)0
    
                                                                                                               Moist Polar
                                                                                                               Total: 1.005% (0.998, 1.011)1
                                                                                                               Cardiorespiratory:
                                                                                                               1.008(0.997,1.018)0
                                                                                                               Other: 1.003% (0.995,1.011)1
    
                                                                                                               Moist Tropical
                                                                                                               Total: 0.999% (0.997, 1.001)2
                                                                                                               Cardiorespiratory:
                                                                                                               0.996(0.993,1.000)2
                                                                                                               Other: 0.998% (0.995,1.001)1
    
                                                                                                               Transition
                                                                                                               Total: 1.005% (0.996, 1.014)1
                                                                                                               Cardiorespiratory:
                                                                                                               1.007(0.994,1.020)1
                 	Other: 1.002% (0.996, 1.008)2
    December 2009                                                   E-354
    

    -------
                  Study
           Design & Methods
            Concentrations!
        Effect Estimates (95% Cl)
    Reference: Rosenthal et al. (2008,
    1569251
    
    Period of Study: Jul 2002-Jul 2006
    
    Location: Indianapolis, Indiana
    Outcome: Non-Dead on Arrival (DOA)   Pollutant: PM
    Out-of-Hospital Cardiac Arrests (OHCA)
    Witnessed non-DOAOHCA
    
    Study Design: Case-crossover
    
    Statistical Analyses: Time-stratified
    conditional logistic regression
    
    Age Groups: All ages
    
    Study Population: Non-DOAOHCA:
    1,374
    
    Witnessed non-DOAOHCA: 511
    Averaging Time: 24-h avg
    Hourly
    Mean (SD):
    NR
    IQR (25th, 75th):
    All non-DOA
    All heart rhythms: (9.4,19.5)
    OHCA: (9.6, 19.5)
    Referents: (9.3,19.5)
    Asystole: (9.2,19.4)
    OHCA: (9.2, 19.7)
    Asystole: (9.2,19.2)
    Wtnessed non-DOA hourly
    All heart rhythms: (8.8, 20.7)
    OHCA: (8.8, 21.9)
    Referents: (8.8, 20.4)
    Asystole: (8.5,19.8)
    OHCA: (9.4, 21.3)
    Referents: (8.3,19.1)
    Copollutant (correlation): NR
    Increment: 10|jg/m
    
    Hazard Ratio (Lower Cl, Upper Cl)
    lag:
    Out-of-Hospital non-DOA Cardiac
    Arrests
                                                                                                                1.02(0.94,
                                                                                                                1.00(0.92,
                                                                                                                0.98 (0.90,
                                                                                                                1.00(0.92,
                                                                                                                1.02(0.92,
                                                                                                                1.01 (0.91,
                                                                                                                1.02(0.91,
                                                                                                                Asystole
                                                                                                                1.03(0.91,
                                                                                                                1.00(0.89,
                                                                                                                1.01 (0.90,
                                                                                                                0.98 (0.87,
                                                                                                                1.03(0.90,
                                                                                                                1.05(0.90,
                                                                                                                1.04(0.88,
                                                                                                                Vfib
                                                                                                                1.08(0.92,
                                                                                                                1.02(0.87,
                                                                                                                0.96 (0.80,
                                                                                                                1.10(0.93,
                                                                                                                1.06(0.88,
                                                                                                                1.01 (0.82,
                                                                                                                1.05(0.83,
                                                                                                                PEA
                                                                                                                0.92 (0.77,
                                                                                                                0.98 (0.83,
                                                                                                                0.96 (0.82,
                                                                                                                0.95 (0.82,
                                                                                                                0.96 (0.80,
                                                                                                                0.98 (0.80,
                                                                                                                0.98 (0.78,
              1.11)0
              1.08)1
              1.06)2
              1.08)3
              1.12)0-1 avg
              1.12) 0-2 avg
              1.14) 0-3 avg
    
              1.17)0
              1.13)1
              1.13)2
              1.10)3
              1.18)0-1 avg
              1.22) 0-2 avg
              1.22) 0-3 avg
    
              1.28)0
              1.21)1
              1.14)2
              1.31)3
              1.28)0-1 avg
              1.25) 0-2 avg
              1.32) 0-3 avg
                                                                                      1.0
                                                                                      1.15)1
                                                                                      1.14)2
                                                                                      1.10)3
                                                                                      1.17)0-1 avg
                                                                                      1.21) 0-2 avg
                                                                                      1.21) 0-3 avg
                                                                                                               Wtnessed Out-of-Hospital non-DOA
                                                                                                               Cardiac Arrests (lag represents h in
                                                                                                               which or h before OHCA occurred)
                                                                                                               All: 1.12 (1.01, 1.25)0
                                                                                                               White: 1.18 (1.03,1.35)0
                                                                                                               60-75:1.25(1.05, 1.49)0
                                                                                                               Asystole: 1.22 (1.01,1.59)0
    Reference: Schwartz et al. (2002,
    0253121
    
    Period of Study: 1979-Late 1980's
    
    Location: 6 U.S. cities
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    
    Study Design: Time-series
    
    Statistical Analyses: Hierarchical
    modeling:
    
    LPoisson GAM, LOESS
    
    2. Multivariate modeling
    
    Age Groups: All ages
    Pollutant: PM25, PM25 sources (Traffic,
    Coal, Residual Oil)
    
    Averaging Time: 24-h avg
    
    Mean (SD):
    
    PM25 Range: (Madison: 11.3 to
    Steubenville: 30.5)
    
    Traffic Range: (Steubenville: 1.5 to
    Boston: 4.8)
    
    Coal Range: (Madison: 4.9 to
    Steubenville: 19.2)
    
    Residual Oil Range: (Boston: 0.5 to
    Steubenville: 0.9)
    
    Range (Min, Max): NR
    The study does not present quantitative
    results.
    December 2009
                                    E-355
    

    -------
                 Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Simpson et al. (2005,
    0874381
    Period of Study: Jan 1996-Dec 1999
    Location: 4 Australian cities
    Outcome: Mortality:
    Nonaccidental (<800)
    Cardiovascular (390-459)
    Respiratory (460-519)
    Study Design: Time-series
    meta-analysis
    Statistical Analyses: Poisson GAM,
    natural splines
    Poisson GLM, natural splines
    Age Groups: All ages
    Pollutant: PM25
    Averaging Time: 24-h avg
    Mean (SD):
    Brisbane: PM25: 7.50
    Sydney: PM25:9.00
    Melbourne: PM25: 9.30
    Perth: PM25: 9.0 pg/m3
    Range (Min, Max):
    Brisbane: PM25: (1.9,19.7)
    Sydney: PM25: (2.4, 35.3)
    Melbourne: PM25: (2.7, 35.1)
    Perth: PM25: (2.8, 37.3)
    Copollutant: CO, N02
    Increment: 10|jg/m
    % Increase (Lower Cl, Upper Cl) lag:
    PM25
    0.9% (-0.7, 2.5)
    Reference: Slaughter et al. (2005,
    0738541
    
    Period of Study: Jan 1995-Dec 1999
    Location: Spokane, Washington
    
    
    
    
    Reference: Stieb et al. (2002, 0252051
    Period of Study: Publication dates of
    studies: 1985-Dec 2000 Mortality
    series: 1958-1999
    Location: 40 cities (11 Canadian cities,
    19 U.S. cities, Santiago, Amsterdam,
    Erfurt, 7 Korean cities)
    
    
    Reference: Sullivan et al. (2003,
    0431561
    
    Period of Study: 1985-1994
    Location: Western Washington
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Mortality:
    
    Nonaccidental (<800)
    Study Design: Time-series
    Statistical Analyses: Poisson GLM,
    natural splines
    Age Groups: All ages
    
    
    Outcome: Mortality:
    All-cause (nonaccidental)
    Study Design: Meta-analysis
    Statistical Analyses: Random effects
    model
    Age Groups: All ages
    
    
    Outcome: Out-of-hospital cardiac
    arrest
    
    Study Design: Case-crossover
    Statistical Analyses: Conditional
    logistic regression
    Age Groups: 19-79
    
    Study Population: Out-of-hospital
    cardiac arrests: 1,206
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (9th, 95th): PM25: (4.2, 20.2)
    Copollutant (correlation):
    PM25:r = 0.95
    PM10:r = 0.62
    PMi0.25:r = 0.31
    CO: r = 0.62
    
    Pollutant: PM25
    Averaging Time: NR
    Mean (SD): NR
    Range (Min, Max): NR
    Copollutant: Varied between studies:
    03
    S02
    N02
    CO
    
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    Median (SD) unit:
    PM,o
    Lag 0: 28.05
    
    Lag 1:27.97
    Lag 2: 28.40
    Range (Min, Max): PM10: (7.38, 89.83)
    
    Copollutant (correlation): S02, CO
    
    Notes: Study used nephelometry to
    measure particles and equated the
    measurements to PM2 5 concentrations.
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Increment:
    PM25: 10|jg/m3
    PM10: 25 pg/m3
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    PM25
    (0.97,1.04)1
    0.99(0.96, 1.03)2
    1.00(0.97, 1.03)3
    Increment: PM25: 18.3 pg/m3
    % Increase (Lower Cl, Upper Cl) lag:
    Single-pollutant models
    18 studies
    PM25:2.0%(1.2, 2.7)
    Multipollutant models
    8 studies
    PM25:1.3%(0.6, 1.9)
    Increment:
    PM10: 16.51 pg/m3
    PM25: 13.8 pg/m3
    Odds Ratio (Lower Cl, Upper Cl) lag:
    Overall
    PM10
    1.05(0.87, 1.27)0
    0.91 (0.75, 1.11) 1
    1.03(0.82,1.28)2
    PM25
    0.94(0.88,1.01)0
    0.94(0.88,1.02)1
    1.00(0.93, 1.08)2
    PM2 5: Stratified by subject
    characteristics
    <55
    0.95(0.76,1.18)0
    0.89(0.71,1.12)1
    0.95(0.75, 1.20)2
    >55
    0.94(0.88,1.02)0
    0.95, (0.88, 1.03)1
    1.01(0.93,1.10)2
    Male
    0.95(0.87, 1.03)0
    0.96(0.88,1.04)1
    1.01(0.93,1.10)2
    Female
    0.93(0.82,1.06)0
    0.92(0.80,1.07)1
    0.98(0.83, 1.15)2
    White
    December 2009
                                   E-356
    

    -------
                 Study                       Design & Methods                Concentrations!             Effect Estimates (95% Cl)
    
                                                                                                            0.93(0.86, 1.01)0
                                                                                                            0.95(0.88, 1.03)1
                                                                                                            1.03(0.95,1.12)2
                                                                                                            Non-White
                                                                                                            1.09(0.88, 1.36)0
                                                                                                            0.96(075,1.22)1
                                                                                                            0.88(0.68,1.14)2
                                                                                                            Current Smoker
                                                                                                            1.05(0.92,1.19)0
                                                                                                            0.98(0.86,1.12)1
                                                                                                            1.06(0.92, 1.22)2
                                                                                                            Nonsmoker
                                                                                                            0.93(0.85,1.01)0
                                                                                                            0.93(0.85, 1.02)1
                                                                                                            0.97(0.89,1.07)2
                                                                                                            Drinker
                                                                                                            1.13(0.92, 1.39)0
                                                                                                            1.15(0.94, 1.41)1
                                                                                                            1.16(0.92,1.45)2
                                                                                                            Nondrinker
                                                                                                            0.94(0.86,1.03)0
                                                                                                            0.93(0.85,1.02)1
                                                                                                            1.00(0.92, 1.10)2
                                                                                                            Activity Level-Unrestricted
                                                                                                            0.96(0.89,1.03)0
                                                                                                            0.96(0.89, 1.04)1
                                                                                                            1.01(0.93,1.10)2
                                                                                                            Activity Level-Limited
                                                                                                            0.82(0.56, 1.20)0
                                                                                                            0.70(0.45,1.09)1
                                                                                                            0.97(0.65,1.43)2
                                                                                                            PM25: Stratified by disease state
                                                                                                            Heart disease
                                                                                                            0.95(0.87, 1.04)0
                                                                                                            0.97(0.89, 1.07)1
                                                                                                            1.06(0.96,1.16)2
                                                                                                            Ischemic Heart Disease
                                                                                                            0.91 (0.80, 1.04)0
                                                                                                            0.97(0.84, 1.11)1
                                                                                                            1.09(0.95,1.26)2
                                                                                                            Active Angina
                                                                                                            0.98(0.81,1.20)0
                                                                                                            1.07(0.88,1.31)1
                                                                                                            1.08(0.89, 1.32)2
                                                                                                            Congestive Heart Failure
                                                                                                            0.91(0.80,1.03)0
                                                                                                            0.99(0.87, 1.13)1
                                                                                                            1.11(0.97,1.26)2
                                                                                                            Supraventricular tachycardia
                                                                                                            1.41 (0.97,2.04)0
                                                                                                            1.55(1.07,2.25)1
                                                                                                            1.23(0.84,1.82)2
                                                                                                            Bradycardia
                                                                                                            0.97(0.64,1.46)0
                                                                                                            1.29(0.85,1.96)1
                                                                                                            1.30(0.84,2.01)2
                                                                                                            Asthma
                                                                                                            (0.80,1.27)0
                                                                                                            0.92(0.71, 1.19)1
                                                                                                            0.93(0.71,1.22)2
                                                                                                            COPD
                                                                                                            1.00(0.86, 1.17)0
                                                                                                            1.04(0.88,1.23)1
                                                                                                            1.08(0.92,1.28)2
    
                                                                                                            PM2 5: Persons with prior recognized
                                                                                                            heart disease stratified by smoking
                                                                                                            status
                                                                                                            All heart disease
                                                                                                            Current smoker
                                                                                                            1.08(0.92, 1.26)0
                                                                                                            1.06(0.89,1.26)1
                                                                                                            1.29(1.06,1.55)2
                                                                                                            Nonsmoker
                                                                                                            0.91(0.82,1.02)0
                                                                                                            0.94(0.84, 1.05)1
                                                                                                            0.99(0.88, 1.11)2
                                                                                                            Ischemic Heart Disease
    December 2009                                                  E-357
    

    -------
                 Study
    Design & Methods
    Concentrations!
    Effect Estimates (95% Cl)
                                                                                                         Current smoker
                                                                                                         1.06(0.84,1.34)0
                                                                                                         0.99(075,1.30)1
                                                                                                         1.39(1.04,1.86)2
                                                                                                         Nonsmoker
                                                                                                         0.86(073,1.02)0
                                                                                                         0.93(078,1.11)1
                                                                                                         0.99(0.83, 1.18)2
                                                                                                         Active Angina
                                                                                                         Current smoker
                                                                                                         1.28(0.88, 1.86)0
                                                                                                         1.26(079,2.01)1
                                                                                                         1.57(0.99,2.48)2
                                                                                                         Nonsmoker
                                                                                                         0.87(0.68,1.12)0
                                                                                                         0.93(072,1.21)1
                                                                                                         0.91 (0.70, 1.17)2
                                                                                                         Congestive Heart Failure
                                                                                                         Current smoker
                                                                                                         1.00(079, 1.28)0
                                                                                                         1.03(078,1.35)1
                                                                                                         1.46(1.10,1.96)2
                                                                                                         Nonsmoker
                                                                                                         0.88(076,1.03)0
                                                                                                         0.96(0.82,1.12)1
                                                                                                         0.99(0.84, 1.17)2
                                                                                                         Supraventricular tachycardia
                                                                                                         Current smoker
                                                                                                         12.80(1.05, 156.57)0
                                                                                                         2.56 (0.82, 7.99) 1
                                                                                                         1.15(0.46,2.86)2
                                                                                                         Nonsmoker
                                                                                                         1.19(074,1.90)0
                                                                                                         1.35(0.87,2.10)1
                                                                                                         1.15(073, 1.82)2
                                                                                                         Bradycardia
                                                                                                         Nonsmoker
                                                                                                         0.84(0.14,4.95)0
                                                                                                         0.42 (0.03, 5.34) 1
                                                                                                         0.51 (0.05, 5.79) 2
                                                                                                         Nonsmoker
                                                                                                         0.99(0.63,1.55)0
                                                                                                         1.42(0.90,2.24)1
                                                                                                         1.39(0.88,2.20)2
    Reference: Thurston et al. (2005,
    0979491
    
    Period of Study: Washington, DC: Aug
    1988-Dec 1997. Phoenix, Arizona:
    1995-1997
    Location: Washington, DC and
    surrounding counties
    Phoenix, Arizona
    
    
    
    Outcome: Mortality:
    Total (nonaccidental) (<800)
    Cardiovascular (390-448)
    Study Design: Time-series
    Source-apportionment
    Statistical Analyses: Poisson GLM,
    natural splines
    Age Groups: Washington, DC: All ages
    Phoenix, Arizona: 2 65
    Pollutant:
    PM25, and source apportioned PM25:
    Crustal
    Traffic
    Secondary S04
    Secondary N03
    Wood
    Oil
    Salt
    Incinerator
    Averaging Time: 24-h avg
    Median (SD) unit: NR
    Range (Min, Max): NR
    Increment: 10|jg/m3
    % Increase:
    Total (nonaccidental):
    Secondary sulfate:
    Phoenix: 5.2%
    Washington, DC: 3.8%
    Motor vehicles:
    Phoenix: 0.9%
    Washington, DC: 4.2%
                                                                       Copollutant: PM25 species (Na, Mg, Al,
                                                                       Si, P, S, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe,
                                                                       Co, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb,
                                                                       Sr, Y, Zr, Mo, Rh, Pd, Ag, Cd, Sn, Sb,
                                                                       Te, I, Cs, Ba, La, W, Au, Hg, Pb, OC,
                                                                       EC)
    December 2009
                           E-358
    

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                  Study
           Design & Methods
            Concentrations!
       Effect Estimates (95% Cl)
    Reference: Villeneuve et al. (2003,
    0550511
    
    Period of Study: 1986-1999
    
    Location: Vancouver, Canada
    Outcome: Mortality:
    
    Nonaccidental (<800)
    
    Cardiovascular (401-440)
    
    Respiratory (460-519)
    
    Cancer (140-239)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson, natural
    splines
    
    Age Groups: 2 65
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    Mean (SD):
    Daily
    PM25:7.9
    Every 6th Day
    PM25:11.6
    
    Range (Min, Max):
    Daily
    PM25: (2.0, 32.0)
    Every 6th Day
    PM25: (1.8, 43.0)
    
    Copollutant:
    S02
    CO
    N02
    03
    Increment:
    PM25(Daily):9.0|jg/m3
    PM25(6thDay):15.7|jg/m3
    
    % Increase (Lower Cl, Upper Cl) lag:
    Nonaccidental
    PM25(Daily)
    -0.1% (-5.1,5.2) 0-2 avg
    -0.1% (-4.1,4.1 0
    -0.3% (-4.2, 3.7 1
    0.5% (-3.3, 4.4) 2
    PM25(6thDay)
    -2.8% (-7.5, 2.1)0
    2.0% (-2.6, 7.0) 1
    4.5% (-0.3, 9.5) 2
    
    Cardiovascular
    PM25(Daily)
    1.5% (-6.1,9.7) 0-2 avg
    4.3% (-1.7, 10.7)0
    -1.0% (-7.0, 5.4 1
    -0.5% (-6.5, 5.9 2
    PM25(6thDay)
    -1.5% (-8.9, 6.5 0
    -2.0% (-9.3, 5.8 1
    3.0% (-4.2, 10.8)2
    Respiratory
    PM25(Daily)
    -0.7% (-13.1, 13.4) 0-2 avg
    6.7% (-3.7, 18.3)0
    -3.0% (-12.8, 7.9)1
    -5.8% (-15.2, 4.7)2
    PM25(6thDay)
    10.0% (-4.7, 26.8) 0
    8.3% (-5.4, 24.0) 1
    0.3% (-12.4, 14.9)2
    
    Cancer
    PM25(Daily)
    -0.3% (-9.4, 9.8) 0-2 avg
    -4.5% (-11.2, 2.8)0
                                                                                                              2.7%
                                                                                                              2.5%
                                                                                -5.0, 11.0)1
                                                                                -5.1,10.7)2
                                                                                                              PM25(6thDay)
                                                                                                              -5.1% (-13.8, 4.5)0
                                                                                                              -0.3% (-9.7,  11.0)1
                                                                                                              0.2% (-9.1, 10.4) 2
    Reference: Wilson et al. (2007,
    1571491
    
    Period of Study: 1995-1997
    
    Location: Phoenix, Arizona
    Outcome: Cardiovascular
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM,
    nonparametric smoothing spline
    
    Age Groups: >25
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 10|jg/m3
    % Excess Risk (Lower Cl, Upper Cl)
    lag:
    Central Phoenix:
    11. 5% (2. 8, 20. 9) 0-5 ma
    6.6% (1.1, 12.5)1
    2.0% (-3.2, 7.5) 2
    Middle Phoenix:
                                                                           2.9%
                                                                           6.4%
                                                                                                                    -4.9, 11. 4) 0-5 ma
                                                                                                                    1.1, 11.9)2
                                                                                                              Outer Phoenix:
                                                                                                              1.6% (-6.2, 10.0) 0-5 ma
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                                    E-359
    

    -------
    Table E-19.    Short-term exposure-mortality - other PM size fractions.
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Perez et al. (2008,1560201  Outcome: Respiratory mortality
    Period of Study: Mar 2003-Dec 2005   Study Design: Cohort
    Location: Barcelona, Spain            Covariates: Temperature, humidity
                                       Statistical Analysis: Autoregressive
                                       Poisson regression models
                                       Statistical Package: NR
                                       Age Groups: All deaths
                                        Pollutant: PMi
                                        Averaging Time: 24 h
                                        Mean (SD) Unit: 20.0 (10.3) pg/m3
                                        Range (Min, Max):  1.9, 80.1
                                        Copollutant: PM10.2.5, PM2.5.i
                                        Increment: 10|jg/m
                                        Odds Ratio (96%CI) lag
                                        Avg 10-1:1.005 (0.960-1.053),
                                        p = 0.824
                                        11:1.012(0.969-1.056), p = 0.599
                                        L2:1.042 (0.998-1.087), p = 0.063
                                        Multi-pollutant Model
                                        Avg 10-1:1.007 (0.957-1.059),
                                        p = 0.799
                                        11:1.008(0.961-1.058), p = 0.739
                                        L2:1.010 (0.963-1059), p = 0.678
    Reference: Perez et al. (2008,1560201  Outcome: Cardiovascular mortality
    Period of Study: Mar 2003-Dec 2005   Study Design: Cohort
    Location: Barcelona, Spain            Covariates: temperature, Humidity
                                       Statistical Analysis: Autoregressive
                                       Poisson regression models
                                       Statistical Package: NR
                                       Age Groups: All deaths
                                        Pollutant: PMi
                                        Averaging Time: 24 h
                                        Mean (SD) Unit: 20.0 (10.3) pg/m3
                                        Range (Min, Max):  1.9, 80.1
                                        Copollutant: PM10.2.5, PM2.5.i
                                        Increment: 10|jg/m
                                        Odds Ratio (96%CI) lag
                                        Avg 10-1:1.028 (1.000-1.057),
                                        p = 0.054
                                        11:1.029(1.003-1.056), p = 0.030
                                        L2:1.023 (0.996-1.050), p = 0.091
                                        Multi-pollutant Model
                                        Avg 10-1:1.025 (0.995-1.057),
                                        p = 0.688
                                        11:1.028(1.000-1.058), p = 0.053
                                        L2:1.024 (0.995-1053), p = 0.110
    Reference: Perez et al. (2008,1560201  Outcome: Cerebrovascular mortality
    Period of Study: Mar 2003-Dec 2005   Study Design: Cohort
    Location: Barcelona, Spain
    Covariates: Temperature, humidity
    Statistical Analysis: Autoregressive
    Poisson regression models
    Statistical Package: NR
    Age Groups: All deaths
    Pollutant: PM,
    Averaging Time: 24 h
    Mean (SD) Unit: 20.0 (10.3) pg/m3
    Range (Min, Max): 1.9, 80.1
    Copollutant: PM10.2.5, PM2.5.,
    Increment: 10|jg/m
    Odds Ratio (96%CI) lag
    Avg 10-1:1037(0.981-1097),
    p = 0.202
    L1:1.056 (1.003-1.113), p = 0.039
    L2:1.020 (0.968-1.075), p = 0.460
    Multi-pollutant Model
    Avg 10-11042(0.981-1.107),
    p = 0.179
    L1:1.063 (1.004-1.124), p = 0.035
    L2:1.034 (0.976-1095), p = 0.255
    Reference: Slaughter et al. (2005,
    0738541
    Period of Study: Jan 995-Dec 1999
    Location: Spokane, Washington
    Outcome: Mortality: Nonaccidental
    (<800)
    Study Design: Time-series
    Statistical Analyses: Poisson GLM,
    natural splines
    Age Groups: All ages
    Pollutant: PM,
    Averaging Time: 24-h avg
    Mean (SD): NR
    Range (9th, 95th)
    PM,: (3.3, 17.6)
    Copollutant (correlation):
    PM,
    PM25:r = 0.95
    PM10:r = 0.50
    PM,0.25:r = 0.19
    CO: r = 0.63
    This study does not present quantitative
    results for PM,.
    Reference: Stolzel et al. (2007, 0913741
    
    Period of Study: Sept 1995-Aug 2001
    Location: Erfurt, Germany
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    Cardio-respiratory (390-459, 460-519,
    785, 786)
    
    Study Design: Time-series
    
    Statistical Analyses: Poisson GAM
    Age Groups: All ages
    
    
    
    
    
    
    
    
    
    Pollutant: MC0.,.o.5, MC0.o,-2.5
    
    Averaging Time: 24-h avg
    Mean (SD):
    MC01.o5: 17.6 (14.8)
    MC00,-25: 22.3 (19.2)
    IQR (25th, 75th):
    MCo,.o5: (8.4, 21.5)
    MCo.oMs: (10.5, 27.3)
    Copollutant (correlation):
    MCo,-o5
    NO: r = 0.52
    N02:r = 0.60
    CO: r = 0.58
    MCo.o,-2.s
    NO: r = 0.51
    N02:r = 0.58
    CO: r = 0.57
    
    Increment:
    MQn-os: 13.1 pg/m3
    MQun.2.5: 16.8 pg/m3
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Total (nonaccidental)
    MCo.,.0.5
    1010(0.986
    1.034)
    0
    1006(0.983
    1.029)
    1
    1007(0.985
    1.029)
    2
    0.994 (0.973
    1.016)
    3
    December 2009
                                   E-360
    

    -------
                  Study                      Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                              1.002(0.981
                                                                                                              1.023)
                                                                                                              4
                                                                                                              0.997 (0.976
                                                                                                              1.018)
                                                                                                              0
                                                                                                              MCooi-25
                                                                                                              1.007(0.985
                                                                                                              1.030)
                                                                                                              0
                                                                                                              1.005(0.984
                                                                                                              1.026)
                                                                                                              1
                                                                                                              1.003(0.983
                                                                                                              1.023)
                                                                                                              2
                                                                                                              0.989 (0.970
                                                                                                              1.009)
                                                                                                              3
                                                                                                              1.002(0.982
                                                                                                              1.022)
                                                                                                              4
                                                                                                              0.998 (0.979
                                                                                                              1.018)
                                                                                                              5
                                                                                                              Cardio-respiratory
                                                                                                              MCO.1-0.5
                                                                                                              1.004(0.977
                                                                                                              1.031)
                                                                                                              0
                                                                                                              1.004(0.979
                                                                                                              1.029)
    
                                                                                                              1.001 (0.978
                                                                                                              1.026)
                                                                                                              2
                                                                                                              0.991 (0.967
                                                                                                              1.014)
    
                                                                                                              1.000(0.977
                                                                                                              1.023)
                                                                                                              4
                                                                                                              1.000(0.976
                                                                                                              1.023)
    
                                                                                                              MCO.01-2.5
                                                                                                              1.001 (0.977
                                                                                                              1.026)
                                                                                                              0
                                                                                                              0.999 (0.976
                                                                                                              1.022)
                                                                                                              1
                                                                                                              0.998 (0.976
                                                                                                              1.021)
                                                                                                              2
                                                                                                              0.985 (0.964
                                                                                                              1.007)
    
                                                                                                              1.001 (0.980
                                                                                                              1.022)
                                                                                                              4
                                                                                                              1.003(0.981
                                                                                                              1.024)
                                                                                                              0
    December 2009                                                  E-361
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Yamazaki et al. (2007,
    0907481
    
    Period of Study: 1995-1998
    
    Location: Hong Kong, China
    Outcome: Mortality:
    
    Intracerebral hemorrhage (431)
    
    Ischaemic stroke (434)
    
    Study Design: Time-stratified case-
    crossover
    
    Statistical Analyses: Conditional
    logistic regression
    
    Age Groups: 2 65
    Pollutant: PM7
    
    Averaging Time: 1-h avg
    Mean (SD):
    Warmer Months (Apr-Sep):
    40.3
    Colder  Months (Oct-Mar):
    39.4
    Range (Min, Max): NR
    Copollutant (correlation):
    Warmer Months
    N02:r = 0.46-0.63
    Ox: r =  -0.14 to 0.20
    Colder  Months
    N02: 0.42-0.79
    Ox: r =  -0.36 to -0.14
    Increment: 30 pg/m
    
    Odds Ratio (Lower Cl, Upper Cl) lag:
    24-h avg concentrations
    Intracerebral hemorrhage
    Warmer months: 1.041 (0.984,1.102)0
    Colder months: 1.005(0.951,1.061)0
    
    Ischaemic stroke
    Warmer months: 1.027 (0.993,1.062)0
    Colder months: 1.005 (0.973,1.039) 0
    
    Exposure measured jointly as 24-h and
    1-h mean concentrations
    Warmer months
    Intracerebral hemorrhage
    1-h with 200 pg/m3 threshold:
    2.397(1.476, 3.892) 2 h
    24-h: 1.019 (0.960, 1.082)0
    
    Ischaemic stroke
    1-h with 200 pg/m3 threshold:
    1.051 (0.750, 1.472) 2 h
    24-h: 1.018 (0.983, 1.055)0
    
    Warmer months
    Intracerebral hemorrhage
    1-h with 200 pg/m3 threshold:
    0.970(0.712, 1.322) 2 h
    24-h: 1.015 (0.958, 1.075)0
    
    Ischaemic stroke
    1-h with 200 pg/m  threshold:
    1.040(0.855, 1.265) 2 h
    24-h: 1.003 (0.968, 1.039)0	
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                                   E-362
    

    -------
    E.4.  Long-Term  Exposure and  Cardiovascular Outcomes
    Table E-20.   Long-term exposure - cardiovascular morbidity outcomes - PM10.
                 Study
           Design & Methods
            Concentrations
       Effect Estimates (95% Cl)
    Reference: Baccarelli et al. (2008,
    1579841
    Period of Study: 1995-2005
    
    Location: Italy (Lombardy region)
    Outcome (ICD9 and ICD10): Deep
    Vein Thrombosis (DVT)
    
    Prothrombin time (PT)
    
    Activated partial thromboplastin time
    (aPTT)
    
    Age Groups: 18-84yrs
    
    Study Design: Case-control (DVT
    outcome)
    
    Cross-sectional (PT and aPTT
    outcomes)
    
    N: 871 cases
    
    1210 controls (randomly selected from
    friends and nonblood relatives of cases
    
    Frequency matched by age to cases)
    
    Statistical Analyses: Unconditional
    logistic regression (DVT outcome)
    
    Linear regression (PT and aPTT
    outcomes)
    
    Covariates: Sex, area of residence,
    education, factor V Leiden or G20210A
    prothrombin mutation, current use of
    oral contraceptives or hormone therapy
    
    (Variables controlled using penalized
    regression splines with 4 df) age, BMI,
    day of yr (for seasonality), index date,
    ambient temperature
    
    Season: covariate
    
    Dose-response Investigated? Yes
    
    Statistical Package: STATAv9.0 and R
    V2.2.0
    Pollutant: PM10
    
    Averaging Time: 1 yr (immediately
    preceding the diagnosis date for cases
    or the date of examination for controls)
    
    assessed other averaging periods
    presented in supplements (90 days, 180
    days, 270 days, 2 yr)
    
    Mean (SD): NR
    
    Percentiles: NR
    
    Range (Min, Max):
    
    Range for tertiles of exposure:
    
    1:12.0-44.2
    
    2:44.3-48.1
    
    3:48.2-51.5
    
    Monitoring Stations: Monitors from 53
    sites
    
    exposure assigned by dividing area into
    9 regions
    
    Copollutant (correlation): NR
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Estimated changes of PT associated
    with PMio:
    Among DVT cases: -0.12 (-0.23, 0.00),
    p = 0.04
    Among Controls: -0.06 (-0.11, 0.00),
    p = 0.04
    
    Estimated changes of a PIT
    associated with PMio:
    Among Controls: -0.09 (-0.19, 0.01),
    p = 0.07
    Among DVT cases: 0.01 (-0.03, 0.04),
    p = 0.78
    
    Risk of DVT associated with PMio
    (avg of 1 yr preceding
    diagnosis/exam date): |
    All subjects:
    1.70(1.30, 2.23), p< 0.001
    Sex:
    Male: 2.07 (1.50, 2.84),  p< 0.001
    Female: 1.40 (1.02,1.92),p = 0.04
    P for interaction: p = 0.02
    Age:
    18-35yrs: 1.57 (1.11, 2.24), p = 0.01
    36-50yrs: 1.97 (1.41, 2.77), p< 0.001
    51-84yrs: 1.54 (0.90, 2.63), p = 0.12
    P for interaction: p =
    0.99Premenopausal women with
    current use of oral contraceptives:
    No: 1.53 (0.86, 2.72), p = 0.14
    Yes: 0.87 (0.46, 1.67), p = 0.68
    P for interaction: p =
    0.11 Postmenopausal women with
    current use of hormone therapy:
    No: 1.60 (0.72, 3.54), p = 0.24
    Yes: 0.85 (0.29, 2.45), p = 0.76
    P for interaction: p = 0.27Current use
    of oral contraceptive or hormone
    replacement therapy:
    No: 1.64 (1.05, 2.57), p = 0.03
    Yes: 0.97 (0.58, 1.61), p = 0.89
    P for interaction: p = 0.048
    Body Mass Index:
    13.3-22.0:1.47(0.97, 2.23), p = 0.07;
    22.1-24.9:1.72 1.17, 2.54), p = 0.006
    25.0-53.3:1.83(1.03, 3.24), p = 0.04
    P for interaction: p = 0.37
    Education: Elementary/middle school:
    1.93(1.35, 2.76), p< 0.001
    High school: 1.72 (1.24, 2.39),
    p = 0.001
    College: 1.35 (0.74, 2.45), p = 0.33
    P for interaction: p = 0.21
    Deficiencies of natural anticoagulant
    proteins:
    None: 1.66 (1.26, 2.18), p< 0.001
    Any: 2.56 (0.91, 7.18), p = 0.07
    P for interaction: p = 0.41
    Factor V Leiden or G20210A
    prothrombin mutation:
    None: 1.69 (1.27, 2.23), p< 0.001
    Any: 1.79 (1.05, 3.05), p = 0.03
    P for interaction: p = 0.83
    Hyperhomocysteinemia:	
    December 2009
                                 E-363
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                 No: 1.66(1.26,2.19), p< 0.001
                                                                                                                 Yes: 2.19 (1.33, 3.61), p = 0.002
                                                                                                                 P for interaction: p = 0.25
                                                                                                                 Any cause of thrombophilia:
                                                                                                                 No: 1.59 (1.19, 2.13), p = 0.002
                                                                                                                 Yes: 1.96 (1.34, 2.87), p< 0.001
                                                                                                                 P for interaction: p = 0.27
                                                                                                                 Year of diagnosis:
                                                                                                                 1995-97:1.61(1.06, 2.46), p = 0.03
                                                                                                                 1998-00:1.34(0.90, 1.99), p = 0.15
                                                                                                                 2001-05:2.14(1.04, 4.39), p = 0.04
                                                                                                                 P for interaction: p = 0.12
                                                                                                                 Risk of DVT associated with PM10
                                                                                                                 over varying averaging times:
                                                                                                                 90 days: 0.91 (0.80,1.03), p = 0.12
                                                                                                                 180 days: 0.96 (0.82, 1.13), p = 0.63
                                                                                                                 270 days: 1.26
                                                                                                                 365 days: 1.70
                                                                                           1.01, 1.57
                                                                                           1.30,2.23
                                                                 p = 0.04
                                                                 p = 0.0001
                                                                                                                 2 yr: 1.47 (1.01, 2.14), p = 0.04
                                                                                                                 Risk of DVT associated with PMio (yr
                                                                                                                 preceding diagnosis/exam date)
                                                                                                                 sensitivity analysis to evaluate the
                                                                                                                 effect of different methods for
                                                                                                                 adjusting for long-term trends:
                                                                                                                 Handling of long-term time trends:
                                                                                                                 Ignored: 1.13 (0.89,1.42), p = 0.31
                                                                                                                 Dummy variable for each yr:
                                                                                                                 1.78(1.31,2.44), p =  0.0003
                                                                                                                 Linear term: 1.32 (1.02,1.69), p = 0.03
                                                                                                                 Penalized spline, 2 df: 1.54 (1.19, 2.00),
                                                                                                                 p = 0.001
                                                                                                                 Penalized spline, 3 df: 1.64(1.26, 2.14),
                                                                                                                 p = 0.0002
                                                                                                                 Penalized spline, 4 df: 1.70 (1.30, 2.23),
                                                                                                                 p = 0.0001
                                                                                                                 Penalized spline, 5 df: 1.70 (1.29, 2.22),
                                                                                                                 p = 0.0002
                                                                                                                 Penalized spline, 6 df: 1.66(1.26, 2.19),
                                                                                                                 p = 0.0003
                                                                                                                 Penalized spline, 7 df: 1.60 (1.21, 2.13),
                                                                                                                 p = 0.001
                                                                                                                 Penalized spline, 8 df: 1.55(1.15, 2.10),
                                                                                                                 p = 0.004	
    Reference: Baccarelli et al. (2009,
    1881831
    Period of Study: Jan 1995-Sept 2005
    
    Location: Lombardia Region, Italy
    Outcome: Deep Vein Thrombosis
    
    Study Design: Case-control
    
    Covariates: Age, Sex, area of
    residence, BMI, education, medication
    use
    
    Statistical Analysis: Logistic
    regression
    
    Statistical Package: Stata
    Pollutant: PM10
    
    Risk of DVT measured with regards to
    distance of residence from major road.
    Specific levels of PM10 not given.
    Increment: NA
    
    Relative Risk (96%CI) of DVT
    
    All subjects, age-adjusted:
    1.33(1.03-1.71), p = 0.03
    All subjects, adjusted for covariates:
    1.47(1.10-1.96), p = 0.008
    All subjects, adjusted for covariates and
    background PM10 exposure: 1.47 (1.11-
    1.96), p = 0.008
    December 2009
                                     E-364
    

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                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Calderon-Garciduenas et
    al. (2008, 1563171
    Period of Study: Children recruited
    between Jul 2003 and Dec 2004
    Location: Mexico (northeast or
    southwest Mexico city or Polotitlan)
    Outcome (ICD9 and ICD10): Plasma
    Endothelin-1 (ET-1) and pulmonary
    arterial pressure (PAP)
    Age Groups: 6-13 yr
    7.9+1.3 yr
    Study Design: Cross-sectional
    N: 81 children
    Statistical Analyses: Analysis of
    variance by parametric one-way
    analysis of variance and the Newman-
    Keuls multiple comparison post test,
    Pearson's correlation
    Covariates: Doesn't appear to have
    performed multivariable analyses
    However, collected information on age,
    place and length of residency, daily
    outdoor time, household cooking
    methods, parents' occupational history,
    family history of atopic illnesses and
    respiratory disease, and personal
    history of otolaryngologic and
    respiratory symptoms
    Season: No
    Dose-response Investigated? No
    Statistical Package: STATAvS.3, or
    GraphPad Software, Inc.
    Pollutant: PM,0 ftjg/rri)
    Exposures assessed quantitatively in
    Mexico City only
    No monitors in Polotitlan
    Averaging Time: 1, 2, and 7 days
    before the exam
    Pollutant concentrations between 0700
    and 1900 h were used for the estimates
    Mean (SD): Presented only in figures
    Percentiles: NR
    Range (Min, Max): Presented only in
    figures
    Monitoring Stations: 4 (2 in northeast
    and 2 in southwest Mexico City)
    Residence and school within 5 mi of
    one of these monitors)
    Copollutant (correlation): 0;
    PM Increment: NA
    Effect Estimate [Lower Cl, Upper Cl]:
    No health effects models with measured
    PM concentrations were presented
    Used city of residence to assign
    exposure
    No multivariable analyses presented
    Authors presented (statistically
    significantly) elevated ET-1 levels
    among children residing in both areas
    of Mexico City as compared to
    Polotitlan (control city):
    Mean + SE (pg/mL)
    Control: 1.23 ±0.06
    Southwest Mexico City: 2.40 ±0.14
    Northeast Mexico City: 2.09 + 0.10
    Mexico City (overall): 2.24 ±0.12
    Authors presented (statistically
    significantly) elevated PAP levels
    among children residing in both areas
    of Mexico City as compared to
    Polotitlan (control city):
    Mean + SE (mmHg)
    Control: 14.6 ±0.4
    Southwest Mexico City: 16.7 + 0.6
    Northeast Mexico City: 18.6 + 0.9
    Mexico City (overall): 17.3 ±0.5
    Correlation between ET-1 and time
    spent outdoors: r = 0.31, p = 0.0012
    Correlation between PAP and time
    spent outdoors: r = 0.42, p = 0.0008
    December 2009
                                     E-365
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Diez Roux et al. (2008,
    1564011
    
    Period of Study: Baseline data
    collected Jun 2000-Aug 2002
    
    Exposure assessed retrospectively
    between Aug 1982 and baseline date
    
    Location: USA (6 field centers:
    Baltimore, MD
    
    Chicago, IL
    
    Forsyth Co, NC
    
    Los Angeles, CA
    
    New York, NY
    
    St. Paul, MN
    Outcome (ICD9 and ICD10): Three
    measures of subclinical atherosclerosis
    (common carotid intimal-medial
    thickness (CIMT), coronary artery
    calcification, and ankle-brachial index
    (ABI))
    
    Age Groups: 44-84 yr (MESA cohort)
    
    Study Design: Cross-sectional
    retrospective cohort
    
    N: 5172 for coronary calcium analysis
    
    5037 for CIMT analysis
    
    5110 for ABI analysis
    
    Statistical Analyses: Generalized
    Additive Models (Binomial regression:
    presence of calcification
    
    Linear regression: CIMT, ABI, amount of
    calcium among persons with non-zero
    calcification)
    
    Covariates: Age, sex, race/ethnicity,
    socioeconomic factors,  cardiovascular
    risk factors (BMI, hypertension, high
    density lipoprotein and low density
    lipoprotein  cholesterol, smoking,
    diabetes, diet,  physical activity
    
    models presented with and without
    adjustment for cardiovascular RFs)
    
    Season: NA
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Pollutant: PM,0 (fjg/nr)
    
    Averaging Time: 20-yr imputed mean
    
    Mean (SD): 34.1 (7.5)
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: A spatio-temporal
    model was used to predict monthly
    PM2s exposures based on the
    geographic location of each
    participant's residence.
    
    Copollutant (correlation with 20-yr
    imputed mean):
    PMio 20-yr observed  mean
    
    r = 0.93
    
    PM25 20-yr imputed mean
    
    r = 0.73
    
    PM10 2001 imputed mean
    
    r = 0.75
    
    PM10 2001 observed  mean
    
    r = 0.80
    
    PM2.5 2001 mean
    PM Increment: 21.0 pg/m (approx.
    10th-90th percentile)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    CIMT:
    Relative difference (95% Cl):
    1.01 (1.00, 1.02)
    Adj. for additional CVD RFs:
    1.02(1.00, 1.03)
    ABI:
    Mean difference (95% Cl):
    0.002 (-0.005, 0.009)
    Adj. for additional CVD RFs:
    0.001 (-0.006, 0.009)
    Coronary calcium:
    Relative prevalence (95% Cl):
    1.02(0.96,1.07)
    Adj. for additional CVD RFs:
    1.02(0.96,1.08)
    Coronary calcium (in those with
    calcium):
    Relative difference (95% Cl):
    0.98(0.84, 1.13)
    Adj. for additional CVD RFs:
    1.01 (0.86, 1.18)
    Found no clear heterogeneity by age,
    sex, lipid status, smoking status,
    diabetes status,  BMI, education or study
    site.
    December 2009
                                    E-366
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Maheswaran et al. (2005,
    0886831
    Period of Study: 1994-1998
    
    Location: Sheffield, United Kingdom
    Outcome (ICD9 and ICD10): Stroke
    mortality (ICD9: 430-438) and
    Emergency hospital admissions (ICD10:
    I60-I69)
    
    Age Groups: 2 45 yr
    
    Study Design: Small area ecological
    cross-sectional
    
    N: 1030 census enumeration districts
    (CEDs)
    
    108 CEDs excluded from PM analyses
    due to artifacts in the modeled
    emissions data. The analysis was
    based on 2979 deaths, 5122
    admissions and a population of 199,682
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Age, sex, socioeconomic
    deprivation, and smoking prevalence
    (some models also included age-by-
    deprivation interaction)
    
    Season: NA
    
    Dose-response Investigated? Yes,
    examined quintiles of exposure
    
    Statistical Package: SAS
    Pollutant: PM,o (fjg/nr)
    
    Averaging Time: 5-yr avg
    
    Mean (SD): Presented mean values
    and ranges for each quintile of
    exposure:
                                                                            2: 17.5 (> 16.8, <18.2)
    
                                                                            3: 18.8 (> 18.2, <19.3)
    
                                                                            4: 19.8 (> 19.3, <20.6)
    
                                                                            5: 23.3 (> 20.6)
    
                                                                            Monitoring Stations: Used air pollution
                                                                            model incorporating point, line and grid
                                                                            sources of pollution and meteorological
                                                                            data.
    
                                                                            Copollutant (correlation):
    
                                                                            CO (r = 0.82)
    
                                                                            N0x(r =  0.87)
    PM Increment: NA
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Rate Ratios (96%CI) for stroke
    mortality adjusted for overdispersion
    by quintile of PMio level
    Adjusted for sex and age:
    1:1 (ref)
    2:0.95(0.84,1.08)
    3:1.12(0.99, 1.27)
    4:1.16 1.03, 1.32)
    5:1.39(1.23,1.58)
    Adjusted for sex, age, deprivation, and
    smoking:
    1:1 (ref)
    2:0.94(0.83, 1.07)
    3:1.08 0.94, 1.24)
    4:1.12(0.97,1.29)
    5:1.33(1.14, 1.56)
    Rate Ratios (96%CI) for emergency
    hospital admissions because of
    stroke by quintile of PMio level
    Adjusted for sex and age:
    1:1 (ref)
    2:1.06(0.95,1.17)
    3:1.10(0.99,1.23)
    4:1.25 1.12, 1.38)
    5:1.40(1.26,1.55)
    Adjusted for sex, age, deprivation, and
    smoking:
    1:1 (ref)
    2:1.01(0.91,1.13)
    3:0.98(0.87, 1.10)
    4:1.08(0.96,1.22)
    5:1.13(0.99,1.29)
    Rate Ratios (96%CI) for stroke
    mortality in relation to spatially
    smoothed (using a 1-km radius)
    modeled outdoor air pollution
    quintiles
    Adjusted for sex, age, socioeconomic
    deprivation, age by deprivation
    interaction, and smoking prevalence:
    1:1 (ref)
    2: 0.86 (0.75, 0.98)
    3:1.05(0.92, 1.21)
    4:1.03 0.89, 1.19)
    5:1.24(1.05,1.47)
    Rate Ratios (96%CI) for emergency
    hospital admissions because of
    stroke in relation to spatially
    smoothed modeled outdoor air
    pollution quintiles
    Adjusted for sex, age, socioeconomic
    deprivation, age by deprivation
    interaction, and smoking prevalence:
    1:1 (ref)
    2:1.05(0.94,1.17)
    3:1.07(0.95,1.20)
    4:1.06 0.94, 1.20)
    5:1.15(1.01,1.31)	
    December 2009
                                    E-367
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Maheswaran et al. (2005,
    0907691
    Period of Study: 1994-1998
    
    Location: Sheffield, United Kingdom
    Outcome (ICD9 and ICD10): Coronary
    Heart Disease (CHD) mortality (ICD9:
    410-414) and Emergency hospital
    admissions (ICD10:120-125)
    
    Age Groups: 2 45 yr
    
    Study Design: Small area ecological
    cross-sectional
    
    N: 1030 census enumeration districts
    (CEDs)
    
    108 CEDs excluded from PM analyses
    due to artifacts in the modeled
    emissions data. Results based on 6857
    deaths, 11407 hospital admissions and
    199,682 people aged > 45 yr
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Age, sex, socioeconomic
    deprivation, and smoking prevalence
    (some models also included age-by-
    deprivation interaction)
    
    Season: NA
    
    Dose-response Investigated? Yes,
    examined quintiles of exposure
    
    Statistical Package: SAS
    Pollutant: PM,0 ftjg/rri )
    
    Averaging Time: 5-yr avg
    
    Mean (SD): Presented mean values
    and ranges for each quintile of
    exposure:
                                                                            2: 17.5 (> 16.8, <18.2)
    
                                                                            3: 18.8 (> 18.2, <19.3)
    
                                                                            4: 19.8 (> 19.3, <20.6)
    
                                                                            5: 23.3 (> 20.6)
    
                                                                            Monitoring Stations: Study used an air
                                                                            pollution  model incorporating points,
                                                                            lines, and grids as sources of pollution,
                                                                            and meteorological data.
    
                                                                            Copollutant (correlation):
                                                                            CO (r = 0.82)
    
                                                                            N0x(r =  0.87)
    PM Increment: NA
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Rate Ratios (96%CI) for CHD
    mortality in relation to modeled
    outdoor air pollution quintiles,
    adjusted for overdispersion
    Adjusted for sex and age:
    1:1 (ref)
    2:1.06(0.98, 1.16)
    3:1.10 1.01,1.21)
    4:1.23(1.13,1.35)
    5:1.30(1.19, 1.43)
    Adjusted for sex, age, deprivation, and
    smoking:
    1:1 (ref)
    2:1.03(0.94, 1.12)
    3:1.00(0.90,1.11)
    4:1.08(0.98, 1.20)
    5:1.08(0.96, 1.20)
    Adjusted for sex, age, deprivation, and
    smoking (spatially smoothed using a
    1km radius):
    1:1 (ref)
    2:0.97(0.89, 1.07)
    3:1.00 0.90, 1.10)
    4:1.03(0.93,1.15)
    5:1.07(0.96, 1.21)
    Rate Ratios (96%CI) for emergency
    hospital admissions from CHD in
    relation to modeled outdoor air
    pollution quintiles
    Adjusted for sex and age:
    1:1 (ref)
    2:1.08(0.98, 1.19)
    3:1.11 (1.01,1.22)
    4:1.17(1.07,1.29)
    5:1.36(1.23,1.50)
    Adjusted for sex, age, deprivation, and
    smoking:
    1:1 (ref)
    2:1.03(0.93, 1.13)
    3:0.96(0.86,1.07)
    4:0.97(0.87,1.08)
    5:1.01 (0.90, 1.14)
    Adjusted for sex, age, deprivation, and
    smoking (spatially smoothed using a
    1km radius):
    1:1 (ref)
    2:1.01(0.92,1.11)
    3:1.04 0.93, 1.15)
    4:0.97(0.87,1.08)
    5:1.07(0.95,1.20)	
    December 2009
                                    E-368
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: O'Neill et al. (2007,
    1560061
    
    Period of Study: 2000-2004
    
    Location: USA (6 field centers:
    Baltimore, MD
    
    Chicago, IL
    
    Forsyth Co, NC
    
    Los Angeles,  CA
    
    New York, NY
    
    St. Paul, MN
    Outcome (ICD9 and ICD10):
    Creatinine adjusted urinary albumin
    excretion
    
    Assessed 2 ways: continuous log
    urinary albumin/creatine ration (UACR)
    and clinically defined micro- or macro-
    albuminuria (UACR > 25 mg/g) vs.
    normal levels
    
    Age Groups: 44-84 yr
    
    Study Design: Cross-sectional
    analyses and prospective cohort
    analyses
    
    N: 3901  participants free of clinical CVD
    at baseline
    
    Statistical Analyses: At baseline:
    multiple  linear regression (continuous
    outcome)
    
    Binomial regression (dichotomous
    outcome)
    
    3-yr change:  repeated measures model
    with random subject effects (estimate 3-
    yr change in  log UACR by levels of
    exposure)
    
    Covariates: Age, gender,  race, BMI,
    cigarette status, ETS, percent dietary
    protein
    
    For repeated measures models: time
    
    Timex PMio
    
    Season: NA
    
    Dose-response Investigated? Yes,
    examined quartiles of exposure
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: Avg of previous
    month, avg of previous 2 mo (recent
    exposures)
    
    20-yr directly monitored PM10 avg,
    20-yr imputed PM10 avg (longer-term
    exposures)
    
    Mean (SD):
    
    Previous 20 yr:  34.7 (7.0)
    
    Previous month: 27.5 (7.9)
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: NR (used closest
    monitor to residence to assign exposure
    
    20-yr imputed PMio was derived using a
    space-time model)
    
    Copollutant (correlation): PM25
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Adjusted mean differences in log
    UACR (mg/g) per increase in PIvl-;
    among participants seen at baseline
    Previous 30 days
    Full sample: -0.42 (-0.085, 0.002)
    Within 10 km:-0.023 (-0.079, 0.034)
    Previous 60 days
    Full sample:-0.056 (-0.106 to-0.005)
    Within 10 km:-0.040 (-0.106, 0.025)
    20 yr PMio (nearest monitors)
    Full sample: -0.019 (-0.072, 0.033)
    Wthin 10 km: 0.009 (-0.067, 0.085)
    Imputed 20 yr exposure
    Full sample: -0.002 (-0.038, 0.035)
    Wthin 10 km: 0.016 (-0.033, 0.066)
    Adjusted relative prevalence of
    microalbuminuria vs. high-normal
    and normal levels (below 26 mg/g)
    per increase in PIvl-: among
    participants without
    macroalbuminuria during the
    baseline visit
    Previous 30 days: 0.88 (0.76,1.02)
    Previous 60 days: 0.83 (0.70, 0.99)
    20 yr PM10 (nearest monitors):
    0.92(0.77, 1.08)
    Imputed 20 yr exposure:
    0.98(0.87,1.10)
    Adjusted mean 3-yr change (SE) in
    log UACR (mg/g) by quartiles of
    1982-2002 exposure to PM10 from
    ambient monitors among
    participants seen in 2000-20004
    Full sample
    Quartile:
    18.5 to  <29.3: 0.147 (0.024)
    29.3 to  <33.1: 0.159 (0.024)
    33.1to<36.3:0.163(0.024)
    36.3(055.7:0.174(0.023)
    p-trend: 0.42
    Within  10 km
    Quartile:
    18.5 to  <29.3: 0.159 (0.030)
    29.3 to  <33.1: 0.155 (0.031)
    33.1to<36.3:0.167(0.028)
    36.3to55.7:0.152(0.036)
    p-trend: 0.99
    Interactions with either 20 yr or shorter-
    term PM exposure were not significant
    (p< 0.01) by gender, age, city,
    race/ethnicity or study site.
    Reference: Puett et al, (2008,1568911
    
    Period of Study: 1992-2002
    
    Location: Northeastern metropolitan
    U.S.
    Outcome: Nonfatal myocardial
    infarction
    
    Study Design: Cohort
    
    Covariates: Age in months, state of
    residence, yr and season
    
    Statistical Analysis: Cox proportional
    hazard
    
    Statistical Package: SAS
    
    Age Groups: 30-55
    Pollutant: PM,0
    
    Averaging Time: 3-, 12-, 24-, 36- and
    48-mo ma
    
    Mean (SD) Unit: NR
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 10|jg/m
    
    Hazard Ratio, 96% Cl, 12 month ma
    
    0.94(0.77-1.15)
    December 2009
                                    E-369
    

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                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Rosenlund et al. (2006,
    1146781
    Period of Study: 1992-1994
    Location: Stockholm County, Sweden
    Outcome (ICD9 and ICD10):
    Myocardial infarction (Ml)
    Age Groups: 45-70 yr
    Study Design: Case-control
    N: 1397 cases
    1870 controls
    Statistical Analyses: Logistic
    regression (main analysis)
    Also performed multinomial logistic
    regression to assess cases as nonfatal,
    fatal in the hospital within 28 days, and
    out-of-hospital death within 28 days with
    all controls as reference
    Covariates: Age, sex, and hospital
    catchment area (frequency matched
    variables)
    Smoking, physical inactivity, diabetes,
    SES
    Also assessed but did not include
    hypertension, BMI, job strain, diet,
    passive smoking, alcohol consumption,
    coffee intake,  and occupational
    exposure to motor exhaust and other
    combustion products
    Season: NA
    Dose-response Investigated? No
    Statistical Package: STATAv8.2
    Pollutant: PM10
    (modeled traffic-related pollution; also
    modeled PM25, but since the PM
    correlation was high (r = 0.998) only
    PM10 results were presented) (|jg/m3)
    Averaging Time: 30 yr (PM only
    assessed during 2000, thus assumed
    constant levels during 1960-2000)
    Median (6th-96th percentile):
    Cases: 2.6 (0.5-6.0)
    Controls: 2.4 (0.6-5.9)
    Range (Min, Max): NR
    Monitoring Stations: NR
    Copollutant (correlation):
    N02(r = 0.93)
    CO (r = 0.66)
    SO,
    PM Increment: 5 pg/rri  (5th to 95th
    percentile distribution among controls)
    Effect Estimate [Lower Cl, Upper Cl]:
    Association of 30-yr avg exposure to air
    pollution from traffic with Ml
    Logistic regression
    All cases: 1.00 (0.79,1.27)
    Multinomial logistic regression
    Nonfatal cases: 0.92 (0.71,1.19)
    Fatal cases: 1.39 (0.94, 2.07)
    In-hospital death: 1.21 (0.75,1.94)
    Out-of-hospital death: 1.84 (1.00,  3.40)
    After adjustment for heating-related
    S02, the estimate for fatal Ml was 1.40
    (0.86-2.26) for PM10.
    December 2009
                                     E-370
    

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                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Zanobetti & Schwartz
    (2007, 0912471
    
    Period of Study: 1985-1999
    
    Location: 21 U.S. cities (Birmingham,
    Alabama
    
    Boulder, Colorado
    
    Canton, Ohio
    
    Chicago, Illinois
    
    Cincinnati, Ohio
    
    Cleveland, Ohio
    
    Colorado Springs, Colorado
    
    Columbus, Ohio
    
    Denver, Colorado
    
    Detroit, Michigan
    
    Honolulu, Hawaii
    
    Houston, Texas
    
    Minneapolis-St. Paul,  Minnesota
    
    Nashville, Tennessee
    
    New Haven, Connecticut
    
    Pittsburgh, Pennsylvania
    
    Provo-Orem, Utah
    
    Salt Lake City, Utah
    
    Seattle, Washington
    
    Steubenville, Ohio
    
    and Youngstown, Ohio)
    Outcome (ICD9 and ICD10): Death,
    subsequent myocardial infarction (Ml
    
    ICD9 codes 410.0-410.9), and a first
    admission for congestive heart failure
    (CHF
    
    ICD9 code 428)
    
    Age Groups: > 65 yr
    
    Study Design: Cohort
    
    N: 196,000 persons discharged alive
    following an acute Ml
    
    Statistical Analyses: Cox's
    Proportional Hazards Regression
    Pollutant: PM,0
    
    Averaging Time: Yearly avg of
    pollution for that yr and lags up to the 3
    previous yr (distributed lag)
    
    Mean (SD): 28.8 (all cities
    
    SD not reported)
    
    Percentiles: 10, 50, and 90 percentiles
    listed  individually for each city (Table 2)
    
    Range (Min, Max): NR
    
    Monitoring Stations: NR (obtained
    data from the U.S. EPAAerometric
    Information Retrieval System)
    Meta-regression for city-specific results   Copollutant (correlation): None
    
    Covariates: Age, sex, race, type of Ml,
    number of days of coronary care and
    intensive care, previous diagnoses for
    atrial fibrillation, and secondary or
    previous diagnoses for COPD,
    diabetes, and hypertension, and for
    season of  initial event (time period, and,
    sex, race,  and type of Ml were treated
    as stratification variables)
    
    Season: Assessed as a confounder
    
    Dose-response Investigated?  No
    
    Statistical Package: NR
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Hazard ratio (95%CI) for an increase in
    PM for the yr of failure and for the
    distributed lag from the yr of failure up
    to 3 previous yr
    Death
    PM,o annual: 1.11 (1.05,1.19),
    p = 0.001
    Distributed lag  model
     Lag 0:1.04  (0.96, 1.14), p = 0.336
     Lag 1:1.07  (0.99, 1.14), p = 0.070
     Lag2:1.14  1.10,1.18, p = 0.000
     Lag 3:1.06  0.99, 1.12  , p = 0.077
     Sum lags 0-3:1.34 (1.14,1.52),
    p = 0.000
    CHF
    PM,o annual: 1.11 (1.03,1.21),
    p = 0.009
    Distributed lag model
     Lag 0:1.09 (1.01,1.18), p = 0.030
     Lag 1:1.09  1.01,1.19, p = 0.038
     Lag2:1.13  1.02, 1.25, p = 0.014
     Lag 3:1.04 (0.97, 1.12), p = 0.260
     Sum lags 0-3:1.41 (1.19,1.66),
    p = 0.000
    2nd Ml
    PM10 annual: 1.17 (1.05,1.31),
    p = 0.003
    Distributed lag model
                                         Lag 0:1.09
                                         Lag 1:1.12
                0.92,1.30
    p = 0.325
    p = 0.108
                                                                              __a  	_ 0.97,  1.30, r   	
                                                                              Lag 2:1.15 (1.08,  1.23), p = 0.000
                                                                              Lag 3:1.01 (0.94,  1.09), p = 0.783
                                                                              Sum lags 0-3:1.43 (1.12,1.82),
                                                                              p = 0.005
                                                                              Hazard Ratio (95%CI) for an increase in
                                                                              PM (sum of the previous 3 yr distributed
                                                                              lag) for the sensitivity analyses
                                                                              Death
                                                                              Subjects with follow-up starting after
                                                                              2nd Ml:
                                                                              1.33(1.15, 1.55), p = 0.000
                                                                              Subjects admitted between 1985-1996:
                                                                              1.45(1.26, 1.68), p = 0.000
                                                                              2nd cohort definition (yr defined at time
                                                                              of Ml):
                                                                              1.29(1.15, 1.44), p = 0.000
                                                                              CHF
                                                                              Subjects with follow-up starting after
                                                                              2nd Ml:
                                                                              1.42(1.22, 1.65), p = 0.000
                                                                              Subjects admitted between 1985-1996:
                                                                              1.51 (1.26, 1.81 ,p = 0.000
                                                                              2nd Ml
                                                                              Subjects admitted between 1985-1996:
                                                                              1.62(1.23, 2.13), p = 0.001
                                                                              Note: Age and sex effect modification
                                                                              results presented in Fig 1
    
                                                                              Used meta-regression to examine
                                                                              predictors of heterogeneity across city
                                                                              and found that most predictors were not
                                                                              significant modifiers of PM (Table 7)
     All units expressed in pg/m  unless otherwise specified.
    December 2009
                                     E-371
    

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    Table E-21.    Long-term  effects-cardiovascular- PIVhs (including PM components/sources).
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Allen et al. (2009,1562091
    
    Period of Study: Oct 2000-Sep 2002
    (exposure averaging period)
    
    outcome assessed in 2002
    
    Location: 5 U.S. communities
    (Chicago, Illinois
    
    Forsyth County, North Carolina
    
    Los Angeles, California
    
    Northern Manhattan and the Bronx,
    New York
    
    and St. Paul, Minnesota)
    
    part of MESA (Multi-ethnic Study of
    Atherosclerosis)
    Outcome (ICD9 and ICD10):
    Abdominal aortic calcium (AAC), a
    marker of systemic atherosclerosis
    (quantitative measure of interest was
    the Agatston score)
    
    Age Groups: 46-88 yr
    
    Study Design: Cross-sectional
    
    N: 1,147 participants (sensitivity
    analysis among 1,269 participants)
    
    Statistical Analyses: 2-part modeling
    approach:
    
    1) Modeled relative risk of having any
    AAC using a log link and a Gaussian
    error model
    
    Sensitivity analysis used modified
    Poisson regression with robust error
    variance
    
    2) Multiple linear regression of the log-
    transformed AAC Agatston score
    (among those with AAC>0)
    
    Sensitivity analysis modeled all
    participants by adding 1 prior to log-
    transforming
    
    Covariates: Age, gender, race/ethnicity,
    BMI,  smoking status, pack-yr of
    smoking, diabetes, education, annual
    income, blood lipid concentration, blood
    pressure, and medications
    
    Assessed impact of gender, age,
    diabetes, obesity, use of lipid-lowering
    medications, education, income,
    race/ethnicity, and employment  status
    on heterogeneity of effects (or in
    sensitivity analyses)
    
    Season: NA
    
    Dose-response Investigated? NR
    
    Statistical Package: SASv9.1
    Pollutant: PM25
    
    Averaging Time: 2-yr averaging period
    (Oct 2000-Sep 2002)
    
    Mean (SD): 15.8 (3.6) pg/m3
    
    Percentiles: NR
    
    Range (Min, Max): 10.6-247 pg/m3
    
    Monitoring Stations: All monitors with
    1) the objective of "population
    exposure," "regional transport," or
    "general/background;) and 2) at least
    50% data reporting in each of 8 3-
    month periods over the averaging time
    
    Used monitors located within 50 km of a
    study participant's residence
    
    Copollutant (correlation):
    Assessed traffic by roadway proximity
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Results for fully adjusted models under
    different participant inclusion,
    employment status, and roadway
    proximity criteria.
    Presence/Absence of Calcium RR
    (95% Cl)
    Inclusion criteria: <10yrs at address:
    1.04(0.89,1.22)
    >10yrs at address: 1.06 (0.96,1.16)
    2 10yrs at address & <10km from
    monitor: 1.08 (0.98,1.18)
    >20yrs at address: 1.10(0.99,1.22)
    2 20yrs at address & <10km from
    monitor: 1.11  (1.00,1.24)
    <10yrs at address & employed:
    1.02(0.87,1.20)
    > 20yrs at address & employed:
    1.07(0.89, 1.27)
    <10yrs at address & not employed:
    1.10(1.00,1.22)
    2 20yrs at address & not employed:
    1.16(1.02,1.31)
    <10yrs at address & near major road:
    0.85(0.69, 1.05)
    2 20yrs at address & not near major
    road: 1.10 (0.99,1.23)
    Log-transformed Agatston Score
    (Agatston >0)
    % Change (96% Cl)
    Inclusion criteria: <10yrs at address:
    -6.6 (-64.0, 50.9)
    2 10yrs at address: 8.0 (-29.7,  45.7)
    2 10yrs at address & <10km from
    monitor: 19.7 (-19.6, 58.9)
    2 20yrs at address: 14.4 (-32.8, 61.7)
    2 20yrs at address & <10km from
    monitor: 24.6 (-24.6, 73.8)
    <10yrs at address & employed:
    29.1 (-25.7,83.8)
    2 20yrs at address & employed:
    43.8 (-32.4, 119.9)
    <10yrs at address & not employed:
    -15.1 (-66.3,36.1)
    > 20yrs at address & not employed:
    -14.1 (-72.6,44.4)
    <10yrs at address & near major road:
    34.0 (-44.2,112.1)
    2 20yrs at address & not near major
    road: 3.9 (-39.9, 47.8)
    Log-transformed Agatston Score (all)
    % Change (95% Cl)
    Inclusion criteria: <10yrs at address: -
    8.5 (-81.3, 64.2)
    2 10yrs at address: 40.7 (-11.5, 92.8)
    2 10yrs at address & <10km from
    monitor: 60.7 (5.9,115.4)
    2 20yrs at address: 64.1  (-1.73,129.9)
    2 20yrs at address & <10km from
    monitor: 79.2 (10.1,148.3)
    <10yrs at address & employed:
    33.5 (-35.9, 102.9)
    > 20yrs at address & employed:
    55.8 (-37.2, 148.7)
    <10yrs at address & not employed:
    54.8 (-23.8, 133.4)
    2 20yrs at address & not employed:
    89.3 (-3.7, 182.3)
    <10yrs at address & near major road:
    -30.6 (-141.3, 80.1)
    2 20yrs at address & not near major
    December 2009
                                    E-372
    

    -------
                 Study                      Design & Methods                Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                            road: 51.3 (-8.3,110.8)
    
                                                                                                            Exploratory/sensitivity analyses
                                                                                                            (also presented in figures):
                                                                                                            Detectable AAC RR (96%CI):
                                                                                                            Among women: 1.14(1.00,1.30)
                                                                                                            Among persons >65yrs:
                                                                                                            1.10(1.01,1.19)
                                                                                                            Among users of lipid-lowering
                                                                                                            medications: 1.14(1.00,1.30)
                                                                                                            Among Hispanics:  1.22 (1.03,1.45)
                                                                                                            Imputing missing covariates among
                                                                                                            residentially stable participants:
                                                                                                            1.08(0.98,  1.19)
                                                                                                            Agatston score % change (96%CI):
                                                                                                            Among Hispanics:  64 (-4,133)
                                                                                                            Among persons earning >$50,000: 72
                                                                                                            (5, 139)
                                                                                                            Agatston score including those with
                                                                                                            Agatston = 0
                                                                                                            % change (96%CI):
                                                                                                            Fully adjusted model: 41 (-12,93)
                                                                                                            Among persons >65yrs: 75 (8,143)
                                                                                                            Among diabetics: 149(29,270)
                                                                                                            Among users of lipid-lowering
                                                                                                            medications: 121 (25, 217)
                                                                                                            Among Hispanics:  141 (45,236)
                                                                                                            Imputing missing
                	Covariates: 49 (1.3,100.1)	
    December 2009                                                  E-373
    

    -------
                   Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Auchincloss et al. (2008,
    1562341
    
    Period of Study: Jul 2000-Aug 2002
    
    Location: 6 U.S. communities
    (Baltimore City and Baltimore County,
    Maryland
    
    Chicago, Illinois
    
    Forsyth County, North Carolina
    
    Los Angeles, California
    
    Northern Manhattan and the Bronx,
    New York
    
    and St. Paul, Minnesota)
    
    part of MESA (Multi-ethnic Study of
    Atherosclerosis)
    Outcome (ICD9 and ICD10): Blood
    pressure: systolic (SBP), diastolic
    (DBP), mean arterial (MAP), pulse
    pressure (PP)
    
    Avg of 2nd and 3rd BP measurement
    used for analyses
    
    Age Groups: 45-84 yr
    
    Study Design: Cross-sectional (Multi-
    Ethnic Study of Atherosclerosis baseline
    examination)
    
    N: 5,112 persons (free of clinically
    apparent cardiovascular disease)
    
    Statistical Analyses: Linear regression
    
    Secondary analyses used log binomial
    models to fit a binary hypertension
    outcome
    
    Covariates: Age, sex,  race/ethnicity,
    per capita family income, education,
    BMI, diabetes status, cigarette smoking
    status, exposure to ETS, high alcohol
    use, physical activity, BP medication
    use, meteorology variables, and
    copollutants
    
    Examined site as a potential
    confounder and effect modifier
    
    Heterogeneity of effects also examined
    by traffic-related exposures, age, sex,
    type 2 diabetes, hypertensive status,
    cigarette use
    
    Season: Adjusted for temperature and
    barometric pressure to adjust for
    seasonality (because seasons vary by
    the study sites)
    
    Also performed sensitivity analyses
    adjusting for season to examine the
    potential for residual confounding not
    accounted for by weather variables
    
    Dose-response Investigated?
    Assessed nonlinear relationships-no
    evidence of strong threshold/nonlinear
    effects for PM25
    
    Statistical Package: NR
    Pollutant: PM25
    
    Averaging Time: 5 exposure metrics
    constructed:  prior day, avg of prior 2
    days, prior 7 days, prior 30 days, and
    prior 60 days
    
    Mean (SD): Prior day: 17.0 (10.5)
    
    Prior 2 days: 16.8 (9.3)
    
    Prior 7 days: 17.0 (6.9)
    
    Prior 30 days: 16.8 (5.0)
    
    Prior 60 days: 16.7 (4.4)
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: Used monitor
    nearest the participant's residence to
    calculate exposure metrics
    
    Copollutant (correlation):
    
    S02
    
    N02
    
    CO
    
    Traffic-related exposures (straight-line
    distance to a highway; total road length
    around a residence)
    PM Increment: 10 pg/m (approx.
    equivalent to difference between 90th
    and 10th percentile for prior 30 day
    mean)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Adjusted mean difference (95% CIJ in
    PP and SBP (mmHg) per 10 pg/m
    increase in PM2 5 (avg for the prior 30
    days)
    Pulse Pressure
    Adjustment variables: Person-level
    Covariates: 1.04 (0.25,1.84)
    Person-level cov,  weather:
    1.12(0.28,1.97)
    Person-level cov,  weather, gaseous
    copollutants: 2.66  (1.61, 3.71)
    Person-level cov,  study site:
    0.93 (-0.04,1.90)
    Person-level cov,  study site, weather:
    1.11  (0.01,2.22)
    Person-level cov,  study site, weather,
    gaseous copollutants: 1.34 (0.10, 2.59)
    Systolic Blood Pressure
    Adjustment variables: Person-level
    Covariates: 0.66 (-0.41,1.74)
    Person-level cov,  weather:
    0.99 (-0.15, 2.13)
    Person-level cov,  weather, gaseous
    copollutants: 2.8 (1.38, 4.22)
    Person-level cov,  study site:
    0.86 (-0.45, 2.17)
    Person-level cov,  study site, weather:
    1.32 (-0.18, 2.82)
    Person-level cov,  study site, weather,
    gaseous copollutants: 1.52 (-0.16, 3.21)
    Additional results: Associations
    became stronger with longer averaging
    periods up to 30 days. For example:
    Adjusted (personal covariates and
    weather) mean differences in PP: Prior
    day:  -0.38 (-0.76, 0.00)
    Prior 2 days:-0.22 (-0.65, 0.21)
    Prior 7 days: 0.52  (-0.08,1.11)
    Prior 30 days: 1.12 (0.28,1.97)
    Prior 60 days: 1.08 (0.11, 2.05)
    (Pattern held for additional adjustments
    and for SBP  results. Therefore, only
    results for 30-day  mean differences
    were presented)
    Additional results (not presented):
    None of DBP results were statistically
    significant. Rresults for MAP were
    similar to SBP,  though weaker and
    generally not significant
    Effect modification: associations
    between  PM2 5  and BP were stronger
    for persons taking medications, with
    hypertension, during warmer weather,
    in the presence of high N02, residing <
    300m from a highway, and surrounded
    by a high density of roads (Fig 1)
    
    Associations were not modified for age,
    sex, diabetes, cigarette smoking, study
    site,  high levels of CO or S02, season  ,
    nor residence < 400m fro a highway
    
    Note: supplementary material available
    on-line
    December 2009
                                     E-374
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Calderon-Garciduenas et
    al. (2009, 1921071
    
    Period of Study: Sept 2004-Jan 2005
    
    Location: Mexico City and Polotitlan,
    Mexico
    Outcome: Flow cytometry
    
    Study Design: Panel
    
    Covariates: NR
    
    Statistical Analysis: Pearson's
    Correlation
    
    Statistical Package: Stata
    
    Age Groups: 9.7 + 1.2yr
    Pollutant: PM25
    
    Averaging Time: 1-, 2- and 7-day avg
    
    Mean (SD) Unit: 35.89 + 0.93 pg/m3
    
    Range (Min, Max): NR
    
    Copollutant: PM10, 03
    Increment: NR
    
    Flow cytometry results and their
    statistical significance in control vs.
    exposed children
    CDS
    Ex posed: 62.9+1.8
    Control: 67.1+1.7
    P = 0.1
    CD4
    Exposed: 39.3+1.3
    Control: 38.2+1.4
    P = 0.57
    CDS
    Exposed: 24.0+0.95
    Control: 27.3+1.0
    P = 0.02
    CD4/CD8
    Exposed: 1.7+0.14
    Control: 1.4+0.07
    P = 0.09
    CD3-/CD19+
    Exposed: 11.8+1.0
    Control: 14.8+1.0
    P = 0.04
    CD56+
    Exposed: 11.5+1.2
    Control: 12.4+1.5
    P = 0.63
    CD56+/CD3-NK
    Exposed: 14.0+9.5
    Control: 7.0+2.7
    P = 0.003
    HLA-DR+
    Exposed: 27.5+4.2
    Control: 17.0+2.4
    P = 0.04
    mCD14+
    Exposed: 66.5+2.3
    Control: 80.6+1.8
    P = <0.001
    CD14/CD69
    Exposed: 0.20+0.07
    Control: 1.0+0.26
    P = O.001
    CD4/CD69
    Exposed: 0.08+0.03
    Control: 3.1+0.65
    P = <0.001
    December 2009
                                   E-375
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Diez Roux et al. (2008,
    1564011
    
    Period of Study: Baseline data
    collected Jun 2000-Aug 2002
    
    Exposure assessed retrospectively
    between Aug 1982 and baseline date
    
    Location: USA (6 field centers:
    Baltimore, MD
    
    Chicago, IL
    
    Forsyth Co, NC
    
    Los Angeles, CA
    
    New York, NY
    
    St. Paul, MN
    Outcome (ICD9 and ICD10): Three
    measures of subclinical atherosclerosis
    (common carotid intimal-medial
    thickness (CIMT), coronary artery
    calcification, and ankle-brachial index
    (ABI))
    
    Age Groups: 44-84 yr
    
    Study Design: Cross-sectional
    
    N: 5172 for coronary calcium analysis
    
    5037 for CIMT analysis
    
    5110 for ABI analysis
    
    Statistical Analyses: Generalized
    Additive Models (Binomial regression:
    presence of calcification
    
    Linear regression: CIMT, ABI, amount of
    calcium)
    
    Covariates: Age, sex, race/ethnicity,
    socioeconomic factors,  cardiovascular
    risk factors (BMI, hypertension, high
    density lipoprotein and low density
    lipoprotein  cholesterol, smoking,
    diabetes, diet, physical activity
    
    Models presented with and without
    adjustment for cardiovascular RFs)
    
    Season: NA
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Pollutant: PM25
    
    Averaging Time: 20-yr imputed mean
    
    Mean (SD): 21.7 (5.0)
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: NR
    
    Long-term exposure to PM estimated
    based on residential history reported
    retrospectively
    
    all addresses geocoded
    
    ambient AP obtained from U.S. EPA
    Copollutant (correlation):
    PM10 20-yr observed mean
    r = 0.64
    PMio 20-yr imputed mean
    r = 0.73
    PM,o 2001 mean
    r = 0.43
    PM252001 mean
    r = 0.64
    Due to high correlation among PM
    exposures, only results of mean 20-yr
    exposures are reported.
    PM Increment: 12.5 pg/m (approx.
    10th-90th percentile)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    CIMT:
    Relative difference (95% Cl):
    1.01 (1.00,1.01)
    Adj. for additional CVD RFs:
    1.01 (1.00, 1.02)
    1.02
    ABI:
    Mean difference (95% Cl):
    0.000 (-0.006, 0.006)
    Adj. for additional CVD RFs:
    -0.001 (-0.006, 0.006)
    
    Coronary calcium:
    Relative prevalence (95% Cl):
    1.01 (0.96,1.05)
    Adj. for additional CVD RFs:
    1.01 (0.96, 1.06)
    1.02
    Coronary calcium (in those with
    calcium):
    Relative difference (95% Cl):
    0.99(0.88, 1.12)
    Adj. for additional CVD RFs:
    1.01 (0.89, 1.14)
    December 2009
                                    E-376
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Hoffman et al. (2007,
    0911631
    Period of Study: 2000-2003
    
    Location: Ruhr area of Germany (3
    large cities:  Essen, Mulheim, and
    Bochum)
    Outcome (ICD9 and ICD10): Coronary  Pollutant: PM
    artery calcification (CAC)
    Age Groups: 45-74 yr
    
    Study Design: Cross-sectional
    
    N: 4494 participants
    
    Statistical Analyses: Linear regression
    (outcome = natural logarithm of CAC
    score + 1)
    
    Logistic regression (outcome = CAC
    score above/below the age- and
    gender-specific 75th percentile)
    
    Covariates: City and area of residence,
    age, sex, education, smoking, ETS,
    physical inactivity, waist-to-hip ratio,
    diabetes, blood pressure, and lipids
    (and household income in a subset)
    
    Season: NA
    
    Dose-response Investigated? Yes,
    PM was also categorized into quartiles
    for analyses
    
    Statistical Package: NR
    Averaging Time: 1 yr (2002, midpoint
    of the study)
    Mean (SD): Total:
    22.8(1.5)
    High traffic exposure (< 100m):
    22.9(1.4)
    Low traffic exposure (>100m):
    22.8(1.5)
    Percentiles:
    Q1:21.54
    Q2: 22.59
    Q31 23 75
    10th-90th percentile: 3.91
    Range (Min, Max): NR
    
    Monitoring Stations: Daily mean PM25
    values for 2002 were estimated with the
    EURAD model using data from official
    emission inventories, meteorological
    information, and regional topographical
    data.
    
    Copollutant (correlation): None
    
    (Traffic was assessed using distance to
    roadways)
    
    Correlation between modeled daily avg
    of PM2.5 and measured PM25: 0.86-
    0.88, depending on season.
    PM Increment: 3.91 pg/rri (10th-90th
    percentile)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Percent change (96%CI) in CAC
    associated with an increase in PM25
    Unadjusted: 12.7 (-7.0, 36.4)
    Model 1 (adjusted for distance to major
    road): 12.3 (-7.3, 35.9)
    Model 2 (model 1 + city and area of
    residence): 29.7 (0, 68.3)
    Model 3 (model 2 + age, sex,
    education): 24.2 (0,55.1)
    Model 4 (model 3 + smoking, ETS,
    physical inactivity, waist-to-hip ratio):
    17.9 (-5.3, 46.7)
    Model 5 (model 4 + diabetes, blood
    pressure, LDL, HDL, triglycerides):
    17.2 (-5.6, 45.5)
    Adjusted ORs(96%CI) for the
    association between the top quarter
    of PM exposure vs. the low quarter
    of PM exposure and a CAC score
    above the age- and sex-specific 76th
    percentiles
    All: 1.22 (0.96, 1.54)
    No CHD: 1.22 (0.95, 1.57)
    Men: 1.09 (0.78,1.53)
    Women: 1.34  (0.97,1.87)
    Age<60yr:1.18(0.83,1.68
    Age >60yr:  1.27 (0.93,1.75
    Nonsmokers:1.17(0.89,1.53)
    Current smokers: 1.30 (0.83, 2.05)
    Educational level
    Low: 1.16 (0.86, 1.57)
    Medium: 1.30  (0.83, 2.05)
    High: 1.62 (0.81, 3.25)
    Additional notes:
    
    No clear dose-response relationship
    demonstrated  when exposure assessed
    in quartiles (Fig 2)
    
    Participants who had not been working
    full-time during the last 5 yr showed
    stronger effects, with possible dose-
    response between PM25 and CAC
    (results presented in Fig 3)
    Reference: Hoffman et al. (2006,
    0911621
    
    Period of Study: Dec 2000-Jul 2003
    
    Location: Ruhr area of Germany (2
    large cities:  Essen, Mulheim)
    Outcome (ICD9 and ICD10): Clinically
    manifest CHD (defined as self-reported
    history of a 'hard' coronary event, i.e.
    myocardial infarction or application of a
    coronary stent or angioplasty or bypass
    surgery)
    
    Age Groups: 45-75 yr
    
    Study Design: Cross-sectional
    (German Heinz Nixdorf RBCALL study)
    
    N: 3399 participants
    
    Statistical Analyses: Multivariable
    logistic regression
    
    Covariates: Sex, diabetes,
    hypertension, smoking status, ETS,
    educational level, physical  activity, BMI,
    triglycerides,  age, cigarettes smoked
    per day, WHR, LDL, HDL, HbAlc,
    indicator variable for cities, indicator
    variable for living in northern part of
    cities.
    
    Statistical Package: SASv8.2
    Pollutant: PM25 (pg/m3)
    
    Averaging Time: Yearly mean
    estimated with model for yr 2002 (on a
    spatial scale of 5 km)
    
    Mean (SD):
    Total: 23.3 (1.4)
    High traffic: 23.4 (1.4)
    Low traffic: 23.3  (1.4)
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: NR
    
    Copollutant (correlation): None
    (Traffic was assessed using distance to
    roadways)
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Model 1: PM25 + high traffic exposure
    
    0.92 (0.36, 2.39)
    
    Model 2: model 1 + age, sex
    
    0.83(0.31,2.27)
    
    Model 3: model 2 + education, diabetes,
    HbAlc, BMI, WHR, smoking status,
    ETS, physical activity, city, area of
    residence
    
    0.56(0.16,2.01)
    
    Model 4: model 3 + hypertension, lipids
    
    0.55(0.14,2.11)
    
    Modeled vs. Measured: r = 0.86-0.88,
    depending on season
    December 2009
                                     E-377
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Hoffmann et al, (2009,
    1903761
    
    Period of Study: 2000-2003
    
    Location: Ruhr area, Germany
    Outcome: Peripheral Arterial Disease
    
    Study Design:
    
    Covariates: Height, weight, medication
    use, diabetes, physical activity level,
    smoking, socioeconomic status,
    education, population density
    
    Statistical Analysis: NR
    
    Statistical Package: NR
    
    Age Groups: 45-75 yr
    Pollutant: PM25
    
    Averaging Time: Daily
    
    Mean (SD) Unit: 22.96 (0.85)
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 3.91 pg/m
    
    Odds Ratio (96%CI) for prevalence of
    peripheral arterial disease
    
    0.87(0.57-1.34)
    Reference: Kunzli et al. (2005, 0873871
    
    Period of Study: 1998-2003
    
    Location: Los Angeles Basin
    Outcome (ICD9 and ICD10): Carotid
    intima-media thickness (CIMT)
    
    Age Groups: Less than 40 yr excluded
    
    Mean age = 59.2 + 9.8
    
    Study Design: Cross-sectional
    
    N: 798 participants
    
    Statistical Analyses: Linear regression
    
    Covariates: Age, sex, education,
    income, smoking, ETS, blood pressure,
    LDL cholesterol, treatment with
    antihypertensives or lipid-lowering
    medications
    
    Season: NA
    
    Dose-response Investigated? Yes,
    assessed PM25 in quartiles
    
    Statistical Package: NR
    Pollutant: PM25 (pg/rri)
    
    Averaging Time: GIS/geostatics model
    to estimate long-term mean ambient
    concentrations of PM25' derived from
    data collected in 2000, including data
    from 23 state and local monitoring
    stations.
    
    Mean (SD): 20.3 ± 2.6
    
    Percentiles: NR
    
    Range (Min, Max): 5.2, 26.9
    
    Monitoring Stations: 23 monitors
    
    Copollutant (correlation): None
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Percent change (95%CI) in CIMT
    associated with an increase in PM25
    concentration
    
    Based on a linear model with log intima-
    media thickness as dependent variable
    Total population:
    Unadjusted: 5.9 (1.0, 10.9), p = 0.018
    Adjusted for age, sex, education,
    income:
    4.4 (0.0, 9.0), p = 0.056
    Adjusted for above + smoking, ETS,
    multivitamins, alcohol:
    4.2 (-0.2, 8.9), p = 0.064
    Among Females Ł 60 yr:
    Unadjusted: 19.2 (8.8, 30.5), p = 0.001
    Adjusted for age, sex, education,
    income:
    15.7(5.7, 26.6), p = 0.002
    Adjusted for above + smoking, ETS,
    multivitamins, alcohol:
    13.8(4.0, 24.5), p = 0.002
    Among those taking lipid-lowering
    therapy:
    Unadjusted: 15.8(2.1, 31.2), p = 0.024
    Adjusted for age, sex, education,
    income:
    13.3(0, 28.5), p = 0.031
    Adjusted for above + smoking, ETS,
    multivitamins, alcohol:
    13.3 (-0.3,  28.8), p = 0.060
    For the observed  contrast between
    lowest and highest exposure:
    Approximately 20 pg/ m  ->  12.1% (2.0-
    231%) increase in CIMT.
    Among nonsmokers: 6.6% (1.0-12.3%).
    
    The estimate was small and not
    significant  in current and former
    smokers.
    Wfomen: In the range of 6-9% per 10
    pg/m3
    
    Unadjusted means of CIMT across
    quartiles of exposure were 734, 753,
    758, and 774 pm
                                                                                                                Adjusted means trend across exposure
                                                                                                                groups, p = 0.041
    
                                                                                                                Stratified results presented in figures
    Reference: Miller et al. (2007, 0901301
    
    Period of Study: 1994-2003
    
    Location: 36 U.S. metropolitan areas
    (Women's Health Initiative)
    Outcome (ICD9 and ICD10): First
    cardiovascular event (myocardial
    infarction, coronary revascularization,
    stroke, and death from either coronary
    heart disease [categorized as "definite"
    or "possible"] or cerebrovascular
    disease)
    
    Age Groups: 50-79 yr (median age at
    Pollutant: PM25 (pg/rri)
    
    Averaging Time: Annual avg
    concentration in 2000 (used to
    represent long-term exposure)
    
    Mean (SD):
    Individual exposure: 13.5 (3.7)
    Citywide avg exposure: 13.5 (3.3)
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Estimated Hazards Ratio (95%CI) for
    the time to the first cardiovascular event
    or death associated with an increase in
    PM25
    Any cardiovascular event (first event)
    Overall: 1.24 (1.09,1.41)	
    December 2009
                                    E-378
    

    -------
                   Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                          enrollment: 63)
    
                                          Study Design: Cohort (median follow-
                                          up of 6 yr)
    
                                          N: 65,893 postmenopausal women
                                          without previous cardiovascular disease
    
                                          Statistical Analyses: Cox-proportional
                                          hazards regression
    
                                          Covariates: Age, race/ethnicity,
                                          smoking status, the number of
                                          cigarettes smoked per day, the number
                                          of yr of smoking, systolic blood pres-
                                          sure,  education level,  household
                                          income, BMI, and presence or absence
                                          of diabetes, hypertension,  or hyper-
                                          cholesterolemia (also  evaluated ETS,
                                          occupation, physical activity,  diet,
                                          alcohol consumption, waist circum-
                                          ference, waist-to-hip ratio,  medical
                                          history, medications, and presence or
                                          absence of a family history of cardio-
                                          vascular disease as possible
                                          confounders in extended models)
    
                                          Season: NA
    
                                          Dose-response Investigated?
    
                                          Statistical Package: SAS v8.0, STATA
                                          v8.0
                                  Median: 13.4
                                  Percentiles:
                                  Quintile ranges:
                                  1:3.4,10.9
                                  2:11.0,12.4
                                  3:12.5, 14.2
                                  4:14.3, 16.4
                                  5:16.5, 28.3
                                  IQR: 11.6-18.3
                                  10th-90th
                                  Personal: 9.1-18.3
                                  City-wide: 9.3-17.8
                                  Range (Min, Max):
                                  Personal exposure: 3.4, 28.3
                                  Citywide exposure: 4.0,19.3
    
                                  Monitoring Stations: 573 monitors
    
                                  The nearest monitor to the location of
                                  each residence was used to assign
                                  exposure (monitor within 30 mi of
                                  residence
    
                                  Median of 20 monitors per city (range:
                                  4-78))
    
                                  Copollutant (correlation):
                                  PM10
    
                                  S02
    
                                  N02
    
                                  CO
    
                                  03
                                 Between cities: 1.15(0.99,1.32)
                                 Within cities: 1.64 (1.24, 2.18)
    
                                 Coronary heart disease (first event):
                                 Overall: 1.21 (1.04,1.42)
                                 Between cities: 1.13 (0.95,1.35)
                                 Within cities: 1.56 (1.11,2.19)
    
                                 Cerebrovascular disease (first event):
                                 Overall: 1.35 (1.08,1.68)
                                 Between cities: 1.20 (0.94,1.54)
                                 Wthin cities: 2.08 (1.28, 3.40)
    
                                 Ml (first event):
                                 Overall: 1.06 (0.85,1.34)
                                 Between cities: 0.97 (0.75,1.25)
                                 Wthin cities: 1.52 (0.91, 2.51)
    
                                 Coronary revascularization (first event):
                                 Overall: 1.20 (1.00,1.43)
                                 Between cities: 1.14 (0.93,1.39)
                                 Wthin cities: 1.45 (0.98, 2.16)
    
                                 Stroke (first event):
                                 Overall: 1.28 (1.02,1.61)
                                 Between cities: 1.12 (0.87,1.45)
                                 Wthin cities: 2.08 (1.25, 3.48)
    
                                 Any death from cardiovascular cause:
                                 Overall: 1.76 (1.25, 2.47)
                                 Between cities: 1.63 (1.10, 2.40)
                                 Wthin cities: 2.28 (1.10, 4.75)
    
                                 Coronary heart disease death (definite
                                 diagnosis):
                                 Overall: 2.21 (1.17, 4.16)
                                 Between cities: 2.22 (1.06, 4.62)
                                 Wthin cities: 2.17 (0.60, 7.89)
    
                                 Coronary heart disease death (possible
                                 diagnosis): Overall: 1.26 (0.62, 2.56)
                                 Between cities: 1.20(0.54,2.63)
                                 Wthin cities: 1.57 (0.29, 8.51)
    
                                 Cerebrovascular disease death:
                                 Overall: 1.83 (1.11, 3.00)
                                 Between cities: 1.58 (0.90, 2.78)
                                 Wthin cities: 2.93 (1.03, 8.38)
                                 Estimated Hazard Ratios for
                                 cardiovascular events associated with
                                 an increase in PM25 according to
                                 selected characteristics (presented
                                 adjusted H and adjusted H including
                                 adjustment for city)
                                 Any cardiovascular event:
                                 H: 1.24 (1.09, 1.41)
                                 H (city): 1.69 (1.26, 2.27)
                                 Household income <$20,000:
                                 H: 1.30 (1.10, 1.53)
                                 H (city): 1.75 (1.28, 2.40)
                                 Household income $20,000-49,999:
                                 H: 1.23 (1.08, 1.41)
                                 H (city): 1.69 (1.25, 2.27)
                                 Household income > $50,000:
                                 H: 1.20 (1.02, 1.40)
                                 6
                                 H (city): 1.66 (1.22, 2.26)
                                 P for trend: HR:p = 0.34
                                 HR (city): p = 0.54
                                 Education: Not high-school graduate:
                                 H: 1.40 (1.11, 1.75)
                                 H (city): 1.88 (1.32, 2.67)
                                 Education: High school grad/trade
                                 school/GED: H:  1.33 (1.14, 1.55)
                                 H (city): 1.79 (1.32, 2.44)
                                 Education: Some college or associate
                                 degree: H: 1.26 (1.09,1.44)	
    December 2009
                              E-379
    

    -------
                   Study                         Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                       H(city): 174(1.29,2.34)
                                                                                                                       Education: Bachelor's degree or higher:
                                                                                                                       H: 1.11 (0.94, 1.31)
                                                                                                                       H (city): 1.54 (1.13, 2.10)
                                                                                                                       P for trend: H:p = 0.07
                                                                                                                       H (city): p = 0.15
                                                                                                                       Age <60yr:H: 1.21 (0.84,1.73)
                                                                                                                       H (city): 1.66 (1.05, 2.61)
                                                                                                                       Age 60-69 yr: H:  1.14 (0.93,1.39)
                                                                                                                       H (city): 1.53 (1.09, 2.14)
                                                                                                                       Age > 70 yr: H: 1.34 (1.11,1.63)
                                                                                                                       H (city): 1.85 (1.34, 2.56)
                                                                                                                       P for trend: H:p = 0.20
                                                                                                                       H (city): p = 0.20
                                                                                                                       Current smoker: H: 1.68 (1.06, 2.66)
                                                                                                                       H (city): 2.28 (1.33, 3.92)
                                                                                                                       Former smoker: H: 1.24 (1.01,1.52)
                                                                                                                       H (city): 1.71 (1.23, 2.39)
                                                                                                                       Never smoked: H: 1.18  (0.99,1.40)
                                                                                                                       H (city): 1.60 (1.16, 2.21)
                                                                                                                       Living with smoker currently:
                                                                                                                       H: 1.28 (0.84, 1.97)
                                                                                                                       H (city): 1.65 (0.99, 2.76)
                                                                                                                       Living with smoker formerly:
                                                                                                                       H: 1.18 (1.00, 1.38)
                                                                                                                       H (city): 1.59 (1.16, 2.16)
                                                                                                                       Living with smoker never:
                                                                                                                       H: 1.39 (1.07, 1.80)
                                                                                                                       H (city): 1.90 (1.31, 2.78)
                                                                                                                       BMK22.5:H: 0.99 (0.80, 1.21)
                                                                                                                       H (city): 1.35 (0.96, 1.88)
                                                                                                                       BMI 22.5-24.7: H: 1.16 (0.96, 1.40)
                                                                                                                       H (city): 1.58 (1.14, 2.19)
                                                                                                                       BMI 24.8-27.2: H: 1.24 (1.05, 1.45)
                                                                                                                       H (city): 1.69 (1.24, 2.30)
                                                                                                                       BMI 27.3-30.9: H: 1.38 (1.18, 1.61)
                                                                                                                       H (city): 1.88 (1.38, 2.56)
                                                                                                                       BMI >30.9:H: 1.35 (1.12, 1.64)
                                                                                                                       H (city): 1.84 (1.33, 2.55)
                                                                                                                       P for trend: H:p = 0.003
                                                                                                                       H (city): p = 0.007
                                                                                                                       Waist-to-hip ratio <0.74:
                                                                                                                       H: 1.07 (0.90, 1.29)
                                                                                                                       H (city): 1.45 (1.05, 2.00)
                                                                                                                       Waist-to-hip ratio 0.74-0.77:
                                                                                                                       H: 1.12 (0.95, 1.31)
                                                                                                                       H (city): 1.51 (1.11,2.06)
                                                                                                                       Waist-to-hip ratio 0.78-0.80:
                                                                                                                       H: 1.24 (1.07, 1.44)
                                                                                                                       H (city): 1.68 (1.23, 2.27)
                                                                                                                       Waist-to-hip ratio 0.81-0.86:
                                                                                                                       H: 1.30 (1.13, 1.50)
                                                                                                                       H (city): 1.76 (1.30, 2.38)
                                                                                                                       Waist-to-hip ratio >0.86:
                                                                                                                       H: 1.29 (1.11, 1.50)
                                                                                                                       H (city): 1.75 (1.29, 2.37)
                                                                                                                       Waist circumference <73 cm:
                                                                                                                       H: 1.05 (0.86, 1.27)
                                                                                                                       H (city): 1.43 (1.02, 1.99)
                                                                                                                       Waist circumference 73-78 cm:
                                                                                                                       H: 1.20 (1.02, 1.41)
                                                                                                                       H (city): 1.63 (1.19, 2.23)
                                                                                                                       Waist circumference 79-85 cm:
                                                                                                                       H: 1.22 (1.05, 1.41)
                                                                                                                       H (city): 1.66 (1.22, 2.24)
                                                                                                                       Waist circumference 86-95 cm:
                                                                                                                       H: 1.33 (1.15, 1.53)
                                                                                                                       H (city): 1.80 (1.33, 2.43)
                                                                                                                       Waist circumference >95 cm:
                                                                                                                       H: 1.27 (1.07, 1.51)
                                                                                                                       H (city): 1.73 (1.26, 2.36)
                                                                                                                       P for trend: H:p = 0.06
                                                                                                                       H (city): p = 0.07
                                                                                                                       Norm one-replacement therapy-Current
                                                                                                                       Use: H: 1.33 (1.09,1.61)
                                                                                                                       H (city): 1.85 (1.32, 2.58)
                                                                                                                       Hormone-replacement therapy-No
                  	Current Use: H: 1.16 (0.98,1.39)
    December 2009                                                       E-380
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                  H(city): 1.57(1.14,2.17)
                                                                                                                  Diabetes-yes: H: 0.96 (0.67,1.37)
                                                                                                                  H (city): 1.24 (0.78, 1.96)
                                                                                                                  Diabetes-no: H: 1.28 (1.12,1.47)
                                                                                                                  H (city): 1.75 (1.30, 2.36)
                                                                                                                  Hypertension-yes: H: 1.22 (1.02,1.45)
                                                                                                                  H (city): 1.65 (1.09, 2.27)
                                                                                                                  Hypertension-no:  H: 1.26 (1.05,1.51)
                                                                                                                  H (city): 1.74 (1.25, 2.40)
                                                                                                                  Hypercholesterolemia-yes:
                                                                                                                  H: 1.25 (0.94, 1.67)
                                                                                                                  H (city): 1.71 (1.15, 2.54)
                                                                                                                  Hypercholesterolemia-no:
                                                                                                                  H: 1.23 (1.07, 1.42)
                                                                                                                  H (city): 1.69 (1.25, 2.28)
                                                                                                                  Family history of CVD-yes:
                                                                                                                  H (city): 1.80 (1.32, 2.44)
                                                                                                                  Family history of CVD-no:
                                                                                                                  H: 1.07 (0.83, 1.37)
                                                                                                                  H (city): 1.46 (1.00, 2.12)
                                                                                                                  Time lived in current state: > 20 yr:
                                                                                                                  H: 1.21 (1.06, 1.39)
                                                                                                                  H (city): 1.66 (1.23, 2.23)
                                                                                                                  Time lived in current state: 10-19 yr:
                                                                                                                  H: 1.39 (1.12, 1.72)'
                                                                                                                  H (city): 1.97 (1.40, 2.79)
                                                                                                                  Time lived in current state: < 9 yr:
                                                                                                                  H: 1.54 (1.06, 2.26)
                                                                                                                  H (city): 2.24 (1.39, 3.59)
                                                                                                                  Health insurance coverage-yes:
                                                                                                                  H: 1.22 (1.07, 1.39)
                                                                                                                  H (city): 1.71 (1.27,2.30)
                                                                                                                  Health insurance coverage-no:
                                                                                                                  H: 1.82 (0.81, 4.10)
                                                                                                                  H (city): 2.65 (1.12, 6.28)
                                                                                                                  Time spent outdoors: <30 min:
                                                                                                                  H: 1.09 (0.86, 1.39)
                                                                                                                  H (city): 1.56 (1.05, 2.31)
                                                                                                                  Time spent outdoors: > 30 min
                                                                                                                  H: 1.26 (1.05, 1.50)
                                                                                                                  H (city): 1.82 (1.29, 2.57)	
    Reference: O'Neill etal. (2007,
    1560061
    Period of Study: 2000-2004
    
    Location: USA (6 field centers:
    Baltimore, MD
    
    Chicago,  IL
    
    Forsyth Co, NC
    
    Los Angeles, CA
    
    New York, NY
    
    St. Paul, MN
    Outcome (ICD9 and ICD10):
    Creatinine adjusted urinary albumin
    excretion
    
    Assessed 2 ways: continuous log
    urinary albumin/creatine ration (UACR)
    and clinically defined micro- or macro-
    albuminuria (UACR 2 25 mg/g) vs.
    normal levels
    
    Age Groups: 44-84 yr
    
    Study Design: Prospective cohort
    analyses (MESA cohort)
    
    N: 3901 participants, free of clinical
    CVD at baseline
    
    Statistical Analyses: Multiple linear
    regression (continuous outcome)
    
    Binomial regression (dichotomous
    outcome)
    
    Covariates: Age, gender, race, BMI,
    cigarette status, ETS, percent dietary
    protein
    
    Season: NA
    
    Dose-response Investigated? Yes,
    examined quartiles of exposure
    
    Statistical Package: SAS
    Pollutant: PM25 (|jg/m3)
    
    Averaging Time: Avg of previous
    month, avg of previous 2 mo (recent
    exposures)
    
    20-yr imputed PM25 avg (longer-term
    exposures)
    
    Mean (SD): Previous month:
    
    16.5(4.8)
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: NR (used closest
    monitor to residence to assign value for
    recent exposures
    
    20-yr PM2 5 exposures were imputed
    using a space-time model.)
    
    Copollutant (correlation): PIvl-;
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Adjusted mean differences in log
    UACR (mg/g) per increase in PM25
    among participants seen at baseline
    Previous 30 days
    Full sample: -0.017 (-0.087, 0.052)
    Within 10 km: 0.026 (-0.067, 0.119)
    Previous 60 days
    Full sample:-0.040 (-0.121, 0.042)
    Within 10 km:-0.013 (-0.122, 0.097)
    Imputed 20 yr exposure
    Full sample: 0.002 (-0.048, 0.052)
    Wthin 10 km:-0.012 (-0.076, 0.053)
    Adjusted relative prevalence of
    microalbuminuria vs. high-normal
    and normal levels (below 26 mg/g)
    per increase in PM2 5 among
    participants without
    macroalbuminuria during the
    baseline visit
    
    Previous 30 days: 0.94 (0.77,1.16)
    
    Previous 60 days: 0.90 (0.71,1.14)
    
    Imputed 20 yr exposure:
    0.98(0.84, 1.14)
    December 2009
                                     E-381
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Solomon et al. (2003,
    1569941
    Period of Study: Exposures measures
    1966-1969
    Health endpoints assessed via
    questionnaire, yr not reported but
    apparently 30 yr after exposure
    assessment (given the 30 yr residency
    requirement)
    Location: United Kingdom
    Outcome (ICD9 and ICD10): Ischemic
    heart disease (a self-reported history of
    medically diagnosed angina or heart
    attack)
    Age Groups: 45 yr and older
    Study Design: Cross-sectional
    N: 1,166 women
    Statistical Analyses: Log linear
    modeling
    Covariates: Smoking, passive smoking
    in childhood,  tenancy, social class,
    worked in industry with respiratory
    hazard, childhood hospital admission
    for chest problem, diabetes, BMI
    Season: NA
    Dose-response Investigated? No
    Statistical Package: STATA
    Pollutant: Black smoke (pg/m )
    Averaging Time: Exposure measures
    performed 1966-1969
    women had to live within 5 miles of their
    current address for the past 30 yr to be
    included
    Mean(SD): 11 wards with pollution
    measures were categorized into high
    (mean >120 pg/m ) and low (mean
    <50 pg/m3) exposure categories when
    classified according to their black
    smoke levels during 1966-69
    SD not reported
    Percentiles: NR
    Range (Min, Max): NR
    Monitoring Stations: NR
    Copollutant (correlation): S0; (health
    results not presented)
    PM Increment: Categorical
    Effect Estimate [Lower Cl, Upper Cl]:
    Association of particulate pollution in
    place of residence and ischemic heart
    disease
    Low(ref): 1.0
    High: 1.0 (0.7, 1.4)
    'All units expressed in ug/m3 unless otherwise specified.
    December 2009
                                    E-382
    

    -------
    E.5. Long-Term  Exposure  and  Respiratory  Outcomes
    Table E-22.   Long-term exposure - respiratory morbidity outcomes - PMio.
                Study
          Design & Methods
           Concentrations
       Effect Estimates (95% Cl)
    Reference: Ackermann-Liebrich et al.
    (1997, 0775371
    
    Period of Study: 1991-1993
    
    Location: Switzerland (Aarau, Basel,
    Davos, Geneva, Lugano, Montana,
    Payerne, Vteld)
    Outcome: Pulmonary function
    
    Age Groups: 18-60yr
    
    Study Design: Cross-sectional
    
    N: 9651 people
    
    Statistical Analyses: Regression
    analysis
    
    Covariates: Age, sex, height, weight,
    education level, nationality, workplace
    exposure
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Pollutant: PM10
    
    Averaging Time: Continuously
    measured, 12-mo. avg. used
    
    Mean (SD): 21.2 (7.4)
    
    Range: (10.1-33.4)
    
    Copollutant (correlation):
    S02:r = 0.93
    
    N02:r = 0.91
    
    03:r = -0.55
    
    Summer Daytime
    03: r = 0.31
    
    Excess 03: r = 0.67
    
    Altitude: r =-0.77
    PM Increment: 10 pg/m
    
    Regression Coefficient p (Lower Cl,
    Upper Cl) for air pollutants as
    predictors of pulmonary function
    
    FVC:-0.0345 (-0.0407 to-0.0283)
    p < 0.001
    FEV,: -0.0160 (-0.0225 to -0.0095)
    p < 0.001
    
    Percent Change (Lower Cl, Upper Cl)
    associated with increase in avg
    annual air pollution concentration
    Healthy Never-smokers
    FVC: -3.39
    p < 0.001
    FEV,:-1.59
    p < 0.001
    All Never-smokers
    FVC:-3.14
    p < 0.001
    FEV,:-1.06
    p < 0.001
    Former Smokers
    FVC: -3.03
    p < 0.001
    FEV,:-0.42
    Current Smokers
    FVC: -3.21
    p < 0.001
    FEV,:-1.35
    p < 0.001
    All
    FVC:-3.14
    p < 0.001
    FEV,:-1.03
    p < 0.001
    Long-term Residents
    FVC:-3.16
    p < 0.001
    FEV,:-0.96
    p < 0.001	
    Reference: Avol et al. (2001, 0205521
    
    Period of Study: 1993-1998
    
    Location: Southern California
    Outcome: FVC, FEV,, MMEF, PEFR    Pollutant: PM
    
    Age Groups: 10yr
    
    Study Design: cohort
    
    N:110
    
    Statistical Analyses: Linear regression
    
    Covariates: Sex, race, cohort entry yr,
    annual avg change in height, weight,
    BMI
    
    Dose-response Investigated? No
    Averaging Time: 24-h PM,0 avgd over
    1994
    
    Mean (SD): 15.0-66.2
    PM Increment: 10 pg/m
    
    Mean Change (Lower Cl, Upper Cl)
    
    FVC:-1.8 (-9.1,5.5)
    
    FEV,:-6.6 (-13.5, 0.3)
    
    MMEF: -16.6 (-32.1 to-1.1)
    
    PEFR:-34.9 (-59.8 to-10.0)
    December 2009
                               E-383
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Bayer-Oglesby et al. (2005,
    0862451
    Period of Study: 1992-2001
    
    Location: Switzerland (Lugano, Zurich,
    Bern, Geneva, Anieres, Biel, Langnau,
    Payerne, & Montana)
    Outcome: Respiratory symptoms
    (chronic cough, bronchitis, cold, dry
    cough, conjunctivitis, wheeze,
    sneezing, asthma, & hay fever)
    
    Age Groups: 6-15 yr
    
    Study Design: Cross-sectional
    
    N: 9,591 children
    
    Statistical Analyses: Logistic
    regression models
    
    Covariates: Age, sex, nationality,
    parental education, number of siblings,
    farming status,  low birth weight, breast
    feeding, smoking, family history of
    asthma, bronchitis and/or atopy, mother
    who smokes, indoor humidity, mode of
    cooking & heating, carpeting, pets,
    removal of carpets/pets for health
    reasons, completed questionnaire &
    month, days max temperature <0°C,
    mother's belief of association between
    environmental exposures & respiratory
    health
    
    Dose-response Investigated? Yes
    
    Statistical Package: STATA
    Pollutant: PM,0
    
    Averaging Time: 12-mo avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Monitoring Stations: 9
    
    Copollutant (correlation): NR
    PM Increment: 10 pg/m
    
    "Fig 2 shows that declining levels of
    PMio were associated with declining
    prevalence of chronic cough, bronchitis,
    common cold, nocturnal dry cough, and
    conjunctivitis symptoms. For wheezing,
    sneezing, asthma, and hay fever, no
    significant association could be seen
    with declining PMio levels."
    
    "Fig 3 illustrates that, on an aggregate
    level, across regions the mean change
    in PM10 levels (r pearson = 0.81,
    p = 0.008). The strongest decline of
    adjusted prevalence of nocturnal dry
    cough was observed in  Geneva,
    Lugano, and Anieres, where the
    strongest reduction of PMio had also
    been achieved."
    Reference: Burr et al. (2004, 0878091
    
    Period of Study: 3 wk in Jul and Jan
    1997 and 2 wk in Nov 1996 and Apr
    1997
    
    Location:  North Wfeles, England
    Outcome: Self-report of symptoms only  Pollutant: PM
    for wheeze, cough, phlegm, rhinitis, and
    itchy eyes.
    Age Groups: all
    
    Study Design: Repeated measures
    
    N: 386 persons in congested streets
    and 425 in the uncongested streets in
    1996/1997. Of these, 165 and 283
    completed the second phase of the
    study.
    Averaging Time: Mean hourly
    concentrations
    Mean (SD): SD NR
    Congested streets -
    1996-9735.2
    1998-9927.2
    
    Uncongested Streets
    1996-9711.6
    1998-998.2
    
    Monitoring Stations: 1 in congested
    street and 1 in uncongested
    Percent change PM10 in congested
    streets: 22.7
    
    Percent change PM10 in
    uncongested streets: 28.9
    
    Uncongested street sampling site was
    20 m from the congested street
    sampler.
    
    The opening of the by-pass produced a
    reduction in pollution  in the congested
    streets. The health effects of these
    changed is likely to be greater for nasal
    and ocular symptoms than for lower
    respiratory symptoms. Uncertainty
    about the causality arises from low
    response rates and conflicting trends in
    respiratory and nasal symptoms.
    December 2009
                                    E-384
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Calderon-Garciduenas et
    al. (2006, 0912531
    
    Period of Study: 1999, 2000
    
    Location: Southwest Mexico City &
    Tlaxcala, Mexico
    Outcome: Hyperinflation, interstitial
    markings-measured by chest
    radiograph, and lung function-FVC,
    FB/1, PEF, FEF25-75, measured using
    spirometry tests
    
    Age Groups: 5-13 yr
    
    Study Design: Cohort
    
    N: 249 (total), 230 (Southwest Mexico
    City),  19 (Tlaxcala)
    
    Statistical Analyses: Bayes test,
    Spearman rank correlation, multiple
    regression
    
    Covariates: Age, sex
    
    Dose-response Investigated? No
    
    Statistical Package: SAS 8.2
    Pollutant: PM,0
    
    Averaging Time: 1 yr
    
    Mean (SD):
    
    Mexico City
    1999-48
    2000-45
    
    Tlaxacala:
    1994-2000: 
    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Downs et al. (2007,
    0928531
    
    Period of Study: 1991, 2002
    
    Location: Switzerland
    Outcome: FEV,, FEV, as % of FVC,
    FEF25-75
    
    Age Groups: 18-60yr
    
    Study Design: Prospective Cohort
    
    N: 4742 people
    
    Statistical Analyses: Linear random
    effects models
    Pollutant: PM,0
    
    Averaging Time: Annual
    
    Mean:
    
    Mean interval exposure: 238 pg/m3/yr
    
    Percentiles:
    
    25th: 197
                                        Covariates: Age, sex, height, parental   75th: 287
                                        smoking, season, education, nationality,
                                        occupational exposure, smoking
                                        (status,  pack-yr), atopy, BMI
    
                                        Dose-response Investigated?
                                        Yes-linear fit best
    
                                        Statistical Package: SAS 9.1, STATA
                                        8.2, R 2.4
    PM Increment: 10 pg/m reduction in
    annual mean
    
    Percent / absolute reduction in annual
    decline in lung function over 11-yr
    period (95% Cl):
    
    Annual decline in  FEV, reduced by 9% /
    3.1  ml (0.03-6.2)
    
    Annual decline in  FEF25.75 reduced by
    16%/11.3 ml/second (4.3-18.2)
    
    Annual decline in  FEVi as a percentage
    of FVC of 0.06 (0.01-0.12)
    
    A reduction in interval exposure of 109
    pg per m3 cubic meter-yr (equivalent to
    a reduction of 10 pg/m  in the annual
    avg during the mean follow-up time of
    10.9 yr) was associated with:
    A reduction of 6.9 ml (95% Cl, 2.1 to
    11.7) in the annual decline in FEV,
    
    A 22% reduction in the annual decline
    in FEF25-75 (i.e.,  by 14.0 ml per
    second 95% Cl, 3.1 to 24.8)
    Reference: Gauderman et al. (2000,
    0125311
    
    Period of Study: 1993-1997
    
    Location: Southern California
    Outcome: FVC, FEV,, MMEF, FEF75    Pollutant: PM10
    
    Age Groups: Fourth, seventh, or tenth   Averaging Time: 24-h avg PM10
    araders
                                        Mean(SD):PMi051.5
    Study Design: Cohort
                                        Copollutant (correlation):
    N: 3035 subjects                     PM25r = 0.96
    
    Statistical Analyses: Linear regression  03 r = -0.32
    
    Covariates: Height, weight, BMI,        PM10.25 r = 0.92
    asthma, smoking, exercise, room
    temperature, barometric pressure        N°2r - °'65
    
    Dose-response Investigated? Yes      Inorg. Acid r = 0.68
    
    Statistical Package: SAS
                                        PM10 Increment: 51.5 pg/m
    
                                        % Change (Lower Cl, Upper Cl)
                                        PM10-4th grade
                                        FVC -0.58 (-1.14to-0.02)
                                        FEV,-0.85 (-1.59 to-0.10)
                                        MMEF-1.32 (-2.43 to-0.20)
                                        FEF75-1.63(-3.14to-0.11)
    
                                        PM10-7th grade
                                        FVC-0.45 (-1.03, 0.13)
                                        FEV,-0.44 (-1.10, 0.23)
                                        MMEF-0.48 (-2.51, 1.59)
                                        FEF75-0.50 (-2.26, 1.29)
    
                                        PM10-10th grade
                                        FVC 0.07 (-0.99, 1.13)
                                        FEV,-0.46 (-1.84, 0.94)
                                        MMEF-0.71  (-4.87,3.63)
                                        FEF75-1.54 (-5.61, 2.71)
    Reference: Gauderman et al. (2002,
    0260131
    
    Period of Study: 1996-2000
    
    Location: Southern California
    Outcome: Lung function development:
    FEV,, maximal  midexpiratory flow
    (MMEF)
    
    Age Groups: Fourth grade children
    (avg age = 9.9 yr)
    
    Study Design: Cohort study
    
    N: 1678 children, 12 communities
    
    Statistical Analyses: Mixed model
    linear regression
    
    Covariates: Height, BMI, doctor-
    diagnosed asthma and cigarette
    smoking in previous yr, respiratory
    illness and exercise on day of test,
    interaction of each of these variables
    with sex, barometric pressure,
    temperature at test time, indicator
    variables for field technician and
    spirometer
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS (10)
    Pollutant: PM,0
    
    Averaging Time: Annual 24-h avg
    
    Mean (SD): The avg levels were
    presented in an online data supplement
    (FigE1)
    
    Monitoring Stations: 12
    
    Copollutant (correlation):
    03(10AMto6PM)r = 0.13
    
    03r = -0.37
    
    N02r = 0.64
    
    Acid vapor r = 0.79
    
    PM25r = 0.95
    
    PM,0.25r = 0.95
    
    EC r = 0.86
    
    OCr = 0.97
    PM Increment: 51.5 pg/m
    
    Association Estimate:
    
    None of the pulmonary function tests
    had a statistically significant correlation
    with PM10
    
    FEV,r = -0.12p = 0.63
    
    MMEF r = -0.22 p = 0.30
    December 2009
                                    E-386
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Gauderman et al. (2004,
    0565691
    
    Period of Study: Air pollution data
    ascertainment: 1994-2000. Spirometry
    testing: Spring 2001-Spring 2003
    
    Location: 12 Communities in Southern
    California
    Outcome: Lung function
    
    FVC, FEV,, MMEF (Maximal
    
    midexpiratory flow rate)
    
    Age Groups: Children, Avg age 10 yr
    
    Study Design: Prospective Cohort
    Study
    
    N: 12 Communities
    
    2,034 Children
    
    24,972 child-months
    
    Statistical Analyses: Linear regression
    of changes in sex-and-community
    specific lung growth function and PM
    
    Covariates: Random effect for
    communities
    
    Season: ALL (except for PM25)
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: 24-h measurements
    over each yr used to create annual avg
    
    Mean: Means are presented in figures
    only.
    
    Range (Min, Max):-15,-65
    
    Monitoring Stations: 12
    
    Copollutant (correlation):
    
    03:r = 0.18
    
    N02:r = 0.67
    
    PM25:r = 0.95
    
    EC: r = 0.85
    
    OC:r = 0.97
    PM Increment: Most to least polluted
    community
    
    Range:
    PMi0:51.4|jg/m3
    EC:1.2|jg/nr
    OC: 10.5 pg/m3
    Difference in Lung Growth [Lower Cl,
    Upper Cl];
    FVC-60.2 (-190.6 to 70.3)
    FEV,-82.1 (-176.9(012.8)
    MMEF-154.2 (-378.3 to 69.8)
    
    EC:
    FVC-77.7 (-166.7to 11.3)
    FEV,-87.9 (-146.4 to-29.4)
    MMEF-165.5 (-323.4 to-7.6)
    
    OC:
    FVC-58.6 (-196.1 to 78.8)
    FEV,-86.2 (-185.6 to 13.3)
    MMEF-151.2 (-389.4 to 87.1)
    
    Correlation with % below 80% predicted
    Lung function (p-value)
    PM,0: 0.66 (0.02)
    EC: 0.74 (0.006)	
    Reference: Gauderman et al. (2007,
    0901211
    Period of Study: 1993-2004
    
    Location: 12 Southern California
    Communities
    Outcome: pulmonary function tests      Pollutant: PM,0
    FVC, FEV,, MMEF/FEF25.75
                                        Monitoring Stations: 1 in each
    Age Groups: Children (mean age 10 at  community
    recruitment, followed for 8 yr)
    
    Study Design: Cohort Study
    (Children's Health Study)
    
    N: 3677 children
    
    (1718 in cohort 1 recruited 1993 and
    1959 in cohort 2 recruited 1996)
    
    22686 pulmonary function tests.
    
    Statistical Analyses: Hierarchical
    mixed effects model with linear splines
    
    Covariates: Adjustments for height,
    height squared, BMI, BMI squared,
    present asthma status, exercise or
    respiratory illness on day of test,
    smoking in previous yr, field  technician,
    traffic indicator (distance from freeway,
    distance from major roads), random
    effects for participant and community.
    
    Dose-response Investigated? no
    
    Statistical Package: SAS
                                        PM Increment: 51.4 pg/m
    
                                        Pollutant effect reported as difference in
                                        8 yr lung function growth from least to
                                        most polluted community. Negative
                                        difference indicates growth deficits
                                        associated with exposure.  For PM10
                                        FEV growth deficit is-111
    December 2009
                                    E-387
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Goss et al. (2004, 0556241
    
    Period of Study: 1999-2000
    
    Location: USA
    Outcome: Cystic Fibrosis pulmonary    Pollutant:
    exacerbations, FEVi
    
    Age Groups: > 6
    
    Study Design: Cohort
    
    N: 11484 patients
    
    Statistical Analyses: Logistic
    regression, t-tests, Mann-Whitney tests,
    Chi-squared tests, polytomous
    regression, multiple linear regression
    
    Covariates: Age, sex, lung function,
    weight, insurance status, pancreatic
    insufficiency,  airway colonization,
    genotype, median household income by
    census tract,  zipcode.
    
    Dose-response Investigated? No
    
    Statistical Package: STATA, SAS
                                        PM Increment: 10 pg/m
    
    Averaging Time: Annual mean of 24-h   Odds Ratio Estimate [Lower Cl,
    avg
    
    Mean (SD): 24.8(7.8) mg/m3
    
    Percentiles: 25th: 20.3
    
    SOth(Median): 24.0
    
    75th: 28.9
    
    Monitoring Stations: 626
    Upper Cl]:
    
    Odds of having 2 or more pulmonary
    exacerbations as compared to 1 or less
    in 2000
    
    1.08(1.02-1.15)
    
    Odds of having 2 or more pulmonary
    exacerbations as compared to no
    exacerbations in 2000
    
    1.09(1.02-1.17)
    
    Decrease in FEV, 38ml(18-58)
    Reference: Hanigan et al, (2008,
    1565181
    Period of Study: Fire Season (Apr-
    Nov) from 1996-2005
    
    Location: Darwin, Australia
    Outcome: Respiratory admissions
    
    Study Design: Time-series
    
    Covariates: Race, age
    
    Statistical Analysis: Over-dispersed
    Poisson generalized linear models
    
    Statistical Package: R
    
    Age Groups: All
    Pollutant: PM10
    
    Averaging Time: Daily levels estimated
    from visibility data
    
    Mean Unit: "Only reported for 2005*
    
    15.31  pg/m3
    
    Range (Min, Max): 6.93, 31.12
    
    Copollutant (correlation): NR
    Increment: 10 pg/m
    
    Percent Increase (96% Cl)
    *Full results reported visually in Fig 3*
    Total Respiratory Admissions
    4.81% (-1.04-11.01)
    Indigenous Respiratory Admissions, No
    
    9.40% (1.04-18.46)
    Non-Indigenous Respiratory
    Admissions, No Lag
    3.14% (-2.99-9.66)
    Indigenous Respiratory Admissions,
    Lag3
    15.02% (3.73-27.54)
    Non-Indigenous Respiratory
    Admissions, Lag 3
    0.67% (-7.55-9.61)
    Indigenous Asthma Admissions, Lag 1
    16.27% (3.55-40.17)
    Non-Indigenous Asthma Admissions,
    Lag1
    8.54% (-5.60-24.80)	
    Reference: Ho et al. (2007, 0932651
    
    Period of Study: Oct 1995-Mar 1996
    
    Location: Taiwan, Republic of China
    Outcome: Asthma
    
    Age Groups: 10-17 yr
    
    Study Design: Screened junior high
    students for asthma, collected
    meteorological data to determine the
    relationship.
    
    N: 69,367
    
    Statistical Analyses: Logistic
    regression model, the maximum
    likelihood estimation with Fisher's
    scoring algorithm, stepwise regression
    model, Wald statistic, Akaike criteria.
    GEE, GENMOD
    
    Covariates: Wind, barometric pressure,
    temperature, rain, humidity
    
    Season: Fall-spring
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: Monthly
    
    Monitoring Stations: 72
    Odds Ratio from stepwise regression
    model:
    
    Females (n = 32, 648)
    
    0.993 [0.990-0.997]
    
    Males: NS
    
    Higher PM10 concentration resulted in
    less asthma prevalence. However, a
    higher number of rain days seemed to
    reduce asthma prevalence
    
    Rain days might interact with PMi0.
    December 2009
                                    E-388
    

    -------
    Study
                                              Design & Methods
                                                                                  Concentrations1
                                                                              Effect Estimates (95% Cl)
    Reference: Hong et al. (2004, 1565651  Outcome: Respiratory symptoms
    „  .  J .^  J  „„„.,                .   „        ,„
    Period of Study: 2001                Age Groups: <12 yr
    
    Location: Kerinci, SP7, and Pelalawan,  Study Design: Disproportionate
    Indonesia                           random sampling was used to select
                                       100 households from  each village. An
                                       interviewer interviewed all children
                                       through the caregiver/parent to obtain
                                       symptoms in the past 2 wk (cough, cold,
                                       nhlenmlanrithpla«M9mn           '
                                       phlegm) and the last 12 mo.
    
                                       N: 382 children
    
                                       Statistical Analyses: Chi-square test,
                                       analysis of variance, prevalence rates,
                                       adjusted odds ratios, multivariate
                                       adjusted odds ratios from multiple
                                       logistic regression models, allowing for
                                       clustering.
                                       _    ..    ,       ,        ,
                                       Covanates: Age, gender, no. of
                                                                          Pollutant: PMi0
                                                                                 .   „     „„,            t
                                                                          Averaging Time: 24-h measurements
                                                                          were taken daily from 2 wk before he
                                                                          fie|d survey to 1 mo after the survey
    
                                                                          Mean(SD):
                                                                          v  .      '„„„„   , ,
                                                                          Kerinci 102.9 (49.6) pg/m3
                                                                          CD7 7, -, ,M 7>
                                                                          SP7 73.7 41.7
                                                                                    -. , M, „
                                                                          Pelalawan 26'1 <145'
                                                                          p
    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Horaket al. (2002, 0347921  Outcome:
    
    Period of Study: 1994-1997
    
    Location: Lower Austria
    Lung function growth measured by
    changes in:
    1. FVC (forced vital capacity)
                                       2. FEV,
    
                                       3. MEF25-75 (midexpiratory flow
                                       between 25-75% of the forced vital
                                       capacity)
    
                                       Age Groups: 2-3 grade schoolchildren
                                       (mean age = 8)
    
                                       Study Design: Prospective cohort with
                                       repeated measures
    
                                       N: 975 children
    
                                       Statistical Analyses: Linear regression
                                       GEE, nonstationary M-dependent
                                       correlation structure
    
                                       Covariates: Gender, atopy, ETS
                                       exposure, baseline lung function, first
                                       height, height difference, school site
    
                                       Season: Winter, summer
    
                                       Dose-response Investigated? No
    Pollutant: PM,0
    
    Mean (SD):
    
    Winter: 21.0(4.8)
    
    Summer:  17.4 (2.8)
    
    Range (Min, Max):
    
    Wnter: 9.4-30.5
    
    Summer:  11.7-28.9
    
    Monitoring Stations:
    
    NR, stations were located in the
    immediate vicinity of each of the 8
    elementary schools
    
    Copollutant (correlation):
    Wnter
    
    03:(r =-0.581)
    
    S02(r = 0.520)
    
    N02(r = 0.595)
    
    Summer
    
    03(r =-0.429)
    
    S02(r = 0.335)
    
    N02(r = 0.412)
    PM Increment: 1 pg/m
    
    Mean per unit increase in PM (p-value)
    
    Outcome: difference per day of FVC
    (mL/day)
    Summer: 0.001  (0.938)
    Wnter: 0.008 (0.042)
    Controlling for temperature:
    Summer:-0.007 (0.417)
    Wnter: -0.003 (0.599)
    Controlling for 03:
    Summer: 0.001  (0.911)
    Wnter: 0.010 (0.019)
    Controlling for N02:
    Summer:-0.018 (0.056)
    Wnter: 0.015 (0.000)
    Controlling for S02:
    Summer: 0.005 (0.575)
    Wnter: 0.004 (0.492)
    In non-asthmatic children:
    Summer:-0.003 (0.710)
    Wnter: 0.009 (0.030)
    In group not exposed to ETS:
    Summer: 0.014 (0.154)
    Wnter: 0.012 (0.0018)
    In group exposed to ETS:
    Summer: 0.022 (0.088)
    Wnter: 0.003 (0.656)
    Outcome: difference per day of FEV,
    (mL/day)
    Summer: -0.023 (0.003)
    Wnter: 0.001 (0.885)
    Controlling for temperature:
    Summer: -0.034 (0.000)
    Wnter: -0.011 (0.016)
    Controlling for 03:
    Summer: -0.022 (0.008)
    Wnter: 0.004 (0.338)
    Controlling for N02:
    Summer: -0.038 (0.000)
    Wnter: 0.011 (0.005)
    Controlling for S02:
    Summer:-0.022 (0.010)
    Wnter: -0.005 (0.358)
    Outcome: difference per day MEF25.75
    (mL/day)
    Summer: -0.090 (0.000)
    Wnter: -0.008 (0.395)
    Controlling for temperature:
    Summer:-0.112 (0.000)
    Wnter:-0.013 (0.295)
    Controlling for 03:
    Summer: -0.087 (0.000)
    Wnter: -0.008 (0.434)
    Controlling for N02:
    Summer:-0.102 (0.000)
    Wnter: 0.005 (0.610)
    Controlling for S02:
    Summer: -0.095 (0.000)
    Wnter: -0.011 (0.474)	
    December 2009
                                    E-390
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Hwang et al. (2006,
    0889711
    
    Period of Study: 2001
    
    Location: Taiwan
    Outcome: Peak expiratory flow rate
    (PEFR), Forced Expiratory Volume in 1
    second (FB/i), Forced Vital Capacity
    (FVC), Self reported "frequent
    coughing," Self reported "shortness of
    breath," Self reported" irritation of
    respiratory tract"
    
    Age Groups: 24-55 yr (mean = 40)
    
    Study Design: Cohort
    
    N: 120 men (60 traffic policemen and
    60 controls)
    
    Statistical Analyses: ANOVA, odds
    ratios calculated from 2X2 table
    
    Dose-response Investigated? No
    Pollutant: PM,0
    
    Mean (SD): 55.58 (16.57)
    
    Percentiles: 25th: 42.96
    
    SOth(Median): 53.81
    
    75th: 70.37
    
    Range (Min, Max): 29.36, 99.58
    
    Monitoring Stations: 22
    Copollutant (correlation):
    N0x(r = 0.34)
    S02(r = 0.58)
    CO (r = 0.27)
    03(r = 0.28)
    PM Increment: 10 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    
    Single pollutant model: 1.00 [0.99,1.02]
    
    Controlling for NOX: 0.99 [0.97,1.00]
    
    Controlling for CO: 1.00 [0.99,1.01]
    
    Controlling for 03:1.00 [0.99,1.02]
    Reference: Hwang et al, (2008,
    1344201
    Period of Study: 2001-2003
    
    Location: Taiwan
    Outcome: Oral Cleft
    
    Study Design: Case-control
    
    Covariates: Maternal age, plurality,
    gestational age, population density and
    season of conception
    
    Statistical Analysis: Logistic
    regression
    
    Age Groups: Infants
    Pollutant: PM,0
    
    Averaging Time: hourly
    Mean (SD) Unit:
    Avg: 54.83+13.07 pg/m3
    Spring: 64.44+ 16.21 pg/m3
    Summer: 39.11 ±8.31 pg/m3
    Fall: 47.76 ±11.77 pg/m*
    Winter: 68.00 ±21.88 pg/m3
    
    Range (Min, Max):
    Avg: 20.75-78.05 pg/m3
    Spring: 23.33-94.33 pg/m3
    Summer: 17.33-60.00 ug/m3
    Fall: 21.00-72.00 pg/m3
    Winter: 21.33-116.00 pg/m3
    
    Copollutant (correlation):
    CO:-0.19
    NOX: 0.56
    03: 0.39
    SO,: 0.50
    Increment: 10|jg/m
    
    Odds Ratio (Min Cl, Max Cl);
    Single Pollutant Model
    Month 1:1.01 (0.96-1.06)
    Month 2:1.00 (0.95-1.05)
    Month 3: 0.99 (0.95-1.05)
    Two Pollutant Model (03 + PM,C
    Month 1:0.99 (0.94-1.04)
                                                                                                               Month 2: 0.99
                                                                                                               Month 3: 0.98
                 0.94-1.04
                 0.93-1.04
                                                                                                               Two Pollutant Model (CO+PM,o)
                                                                                                               Month 1:1.01 0.96-1.06
                                                                                                               Month 2:1.00 0.95-1.05
                                                                                                               Month 3: 0.99 (0.95-1.05)
                                                                                                               Two Pollutant Model (NOx+PM,o)
                                                                                                               Month 1:1.02 (0.97-1.08)
                                                                                                               Month 2:1.01 (0.95-1.07)
                                                                                                               Month 3:1.01 (0.95-1.07)
                                                                                                               Three Pollutant Model (03 + CO +
                                                                                                               PM,0)
                                                                                                               Month 1:0.99
                                                                                                               Month 2: 0.99
                                                                                                                            0.94-1.04
                                                                                                                            0.94-1.04
                                                                                                               Month 3: 0.99 (0.93-1.04)
                                                                                                               Three Pollutant Model (03 + NOX +
                                                                                                               PM,0)
                                                                                                               Month 1:1.00 (0.94-1.06)
                                                                                                               Month 2: 0.98 0.92-1.05
                                                                                                               Month 3:1.00 0.93-1.06
    December 2009
                                    E-391
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ingle et al. (2005, 0890141
    
    Period of Study: May 2003-Apr 2004
    
    Location: Jalgaon  City, India
    Outcome: Peak expiratory flow rate
    (PEFR), Forced Expiratory Volume in 1
    second (FB/i), Forced Vital Capacity
    (FVC), Self reported "frequent
    coughing," Self reported "shortness of
    breath," Self reported" irritation of
    respiratory tract" Age Groups: 24-55 yr
    (mean = 40)
    
    Study Design: Cohort
    
    N: 120 men (60 traffic policemen and
    60 controls)
    
    Statistical Analyses: ANOVA, odds
    ratios calculated from 2X2 table
    
    Dose-response Investigated? No
    Pollutant: PM,0
    
     Mean (SD): Location-specific means:
    
    Prabhat: 224 (27)
    
    Ajanta:269(41)
    
    Icchdevi: 229 (24)
    
    Monitoring Stations: 3
    OR Estimate [p-value]
    Self reported frequent coughing
    2.96 [p < 0.05]
    Self reported shortness of breath
    1.22 [p< 0.05]
    Self reported irritation in respiratory
    tract
    7.5 [p < 0.05]
    Observed/expected lung function
    p-value for difference between groups:
    FVC(L)
    Traffic policemen: 0.82
    Controls: 0.99
    Traffic policemen:
    Obs = 3.03±1.7Exp = 3.70±2.8
    Controls:
    Obs = 3.18 +0.91 Exp = 3.19 ±1.71
    FEV, (L)
    Traffic policemen: 0.73
    Controls: 1.18
    Traffic policemen:
    Obs = 2.27 ± 1.05 Exp = 3.08 ±2.7
    Controls:
    Obs = 3.61 ± 0.90 Exp = 3.06 ±0.91
    PEFR (L/s)
    Traffic policemen: 0.66
    Controls: 0.92
    Traffic policemen:
    Obs = 6.05 ± 2.15 Exp = 9.21 ±0.47
    Controls:
    Obs = 5.54 ±1.85 Exp = 6.11 ±2.31
    Reference: Islam et al. (2007, 0906971   Outcome: Respiratory symptoms,
    
    Period of Study: 2006
                                        Study Design: Longitudinal study
    Location: 12 California communities     cohort
    
                                        Statistical Analyses: Cox proportional
                                        hazards regression
    
                                        Age Groups:
                                        7-9
                                        10-11
                                        Pollutants: PM10
    
                                        Averaging Time: 24-h avg
    
                                        Copollutants (correlation):
                                        03
    
                                        N02
    
                                        EC
    
                                        OC
                                        The study doesn't present quantitative
                                        results on PMi0.
    December 2009
                                    E-392
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Janssen et al. (2003,
    1335551
    
    Period of Study: Apr 1997-Jul 1998
    
    Location: Netherlands-24 schools
    Outcome: Symptoms of asthma and
    allergic disease (asthma, conjunctivitis,
    hay fever, itchy rash, eczema, phlegm,
    bronchitis), skin prick test (SPT)
    reaction to allergens, lung function
    (forced vital capacity [FVC], forced
    expiratory volume in 1 second [FEVi],
    and positive test for fall in FEV, > 15%
    after inhalation of maximal 23 ml
    hypertonic saline [BHR = bronchial
    hyper-responsiveness])
    
    Age Groups: 7-12 yr old
    
    Study Design: Cohort
    
    N: 24 schools (see notes)
    
    Statistical Analyses: Multilevel model
    
    Covariates: Age, sex, non-Dutch
    nationality, cooking on gas, current
    parental smoking, current pet
    possession, parental education level,
    number of persons in the household,
    presence of an unvented water heater
    in kitchen, questionnaire not filled out
    by the mother, presence of mold stains
    in kitchen or living room or bedroom,
    parental respiratory symptoms, distance
    of home to motorway, cough or cold at
    time of lung function measurement,
    bronchitis or severe cold or flu in 3 wk
    preceding measurement, season
    
    Dose-response Investigated? No
    
    Statistical Package: MLwiN
    Pollutant: PM25
    
    Averaging Time: Annual
    
    Mean (SD): 20.5 pg/m3 (2.2)
    
    Percentiles:
    
    25th: 18.6
    
    50th (Median): 20.4
    
    75th: 22.1
    
    Range (Min, Max):
    
    17.3, 24.4
    PM Increment: 'Difference between the
    maximum and the minimum of the
    exposure indicator' (3.5 pg/m3)
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Current wheeze 1.51 (0.90, 2.53)
    Asthma ever 1.03 (0.59,1.82)
    Current conjunctivitis 2.08 (1.17, 3.71)
    Hay fever ever 2.28 (1.13, 4.57)
    Current itchy rash 1.63 (0.91, 2.89)
    Eczema ever 1.31 (0.94,1.83)
    Current phlegm 1.53 (0.74, 3.19)
    Current bronchitis 1.71  (0.84, 3.50)
    Elevated total IgE 1.45 (0.74, 2.84)
    Any allergen (spt reactivity) 1.33 (0.83,
    2.11)
    Indoor allergens (spt reactivity) 1.17
    (0.70,1.94)
    Outdoor allergens (spt  reactivity) 1.90
    (1.06, 3.40)
    FVC < 85% predicted 0.54 (0.29,1.00)
    FEV, < 85% predicted 0.88 (0.37, 2.09)
    BHR 0.93 (0.51, 1.68)
    Notes:
    Fig 1 of the article illustrates the
    association between exposures,
    including PM25, and various respiratory
    symptoms among children with and
    without a positive SPT and positive
    BHR.  In general, the association
    between PM2 5 and respiratory
    symptoms were higher for children with
    a positive SPT or BHR, except for the
    outcome of current phlegm. This effect
    appeared to be the strongest for
    children with a positive BHR,
    particularly for current wheeze and
    current bronchitis.
    
    The authors also  reported separate
    analyses for children with SPT reactivity
    for indoor and outdoor allergens, but did
    not report any clear differences
    between the two groups. The authors
    did  report,  in the text, that the OR of
    PM25 exposure for children sensitized
    for outdoor allergens was 7.64 for
    current itchy rash (p < 0.05).
    December 2009
                                     E-393
    

    -------
                  Study
           Design & Methods
                                                Concentrations1
        Effect Estimates (95% Cl)
    Reference: Kan, et al. (2007, 0913831
    
    Period of Study: 1987-1992
    
    Location: Four Communities in the
    U.S.: Forsyth County, North Carolina
    
    Jackson, Mississippi
    
    northwest suburbs of Minneapolis,
    Minnesota
    
    and Washington County, Maryland.
    Outcome: FEV, and FVC
                                        Pollutant: PM,(
    Age Groups: Middle-aged (mean age   Averaging Time: 24-h PM10 averaged
    was 54.2 yr)                          over study period
    
    Study Design: Hierarchical regression   PM Component: Vehicle emissions
    
    N: 15,792                            Monitoring Stations: 0
    
                                        Copollutant:
    Statistical Analyses: SAS PROC
    MIXED
    
    Covariates: Distance to major roads,
    traffic exposure, age, ethnicity, sex,
    smoking, environmental tobacco smoke
    exposure, occupation, education,
    medical  history, BMI.
    
    Dose-response Investigated? No
    
    Statistical Package:
    
    SPSS Version 11 for traffic density,
    
    SAS Version 9.1.2 for statistical
    analysis
                                        N02
    
                                        03
    RR Estimate (Lower Cl, Upper Cl):
    (Note: for ARIC participants living <150
    meters from major roads)
    Wfomen
    FEV,(mL)
    Age-adjusted model
    -29.5 (-52.2 to -6.9)
    Multivariate model
    -15.7 (-34.4 to-2.9)
    FVC (ml)
    Age-adjusted model
    -33.2 (-60.4 to -5.9)
    Multivariate model
    -24.2 (-46.2,-2.3)
    FEV,/FVC (%)
    Age-adjusted model
    -0.1(-0.5,0.2)
    Multivariate model
    0.1 (-0.3,0.4)
    Men
    FEV,(mL)
    Age-adjusted model
    -38.4 (-76.7,0.6)
    Multivariate model
    -6.4 (-38.1,25.3)
    FVC (ml)
    Age-adjusted model
    -17.0(-62.0,28.0)
    Multivariate model
    10.9(-24.7,46.5)
    FEV,/FVC (%)
    Age-adjusted model
    -0.05 (-0.9,0.0)
    Multivariate model
    -0.3 (-0.7,0.2)	
    Reference: Kim et al. (2005, 0874181
    
    Period of Study: Mar and Dec 2000
    
    Location: Incheon & Ganghwa, Korea
    Outcome: Lung function (FEV,, FVC)
    
    Age Groups: Middle school students
    
    Study Design: Panel
    
    N: 368 children
    
    Statistical Analyses: Generalized liner
    model
    
    Covariates: Gender, grade
    
    Season: Spring and fall
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
                                        Pollutant: PM,0
    
                                        Averaging Time: Monthly
                                        Mean (SD):
                                        Incheon
                                        Mar 64
                                        Dec 54
    
                                        Ganghwa
                                        Mar 64
                                        Dec 53
                                        Range (Min, Max): NR
    PM Increment: NR
    
    OR Estimate [Lower Cl, Upper Cl]:
    
    "The present study showed that the
    values of FEVi and FVC were greater in
    Dec than in Mar for both male and
    female students at all academic
    yr... Because only the level of PMi0 was
    significantly higher for Mar than for Dec
    in both areas, the authors suggest that
    decrements of pulmonary function in
    Mar for both areas are associated with
    the increased level of PM10"
    Reference: Kim et al. (2004, 0873831
    
    Period of Study: Mar-Jun (spring)
    2001
    
    Sep-Nov (fall) 2001
    
    Location: Alameda County, CA
    Outcome: Asthma, bronchitis
    
    Age Groups: Children (in grades 3-5)
    
    Study Design: Cross-sectional
    
    N: 1109 children, 871 (long term
    resident children), 462 (long term
    related females), 403 (long term related
    males)
    
    Statistical Analyses: 2-stage multiple
    logistic regression model
    
    Covariates:  Respiratory illness before
    age of 2, household mold/moisture,
    pests, maternal history of asthma (for
    asthma) Season: Spring and fall
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS 8.2
                                        Pollutant: PM,0
    
                                        Averaging Time: 9 wk
    
                                        Mean (SD): Study Avg 30
    
                                        Monitoring Stations: 10
    
                                        Copollutant (correlation): r2 is
                                        approximately 0.9 for all copollutants
                                        BC, PM25, NOX, N02, NO (NOX-N02)
    PM Increment: 1.4 (IQR)
    
    OR Estimate [Lower Cl, Upper Cl]:
    Bronchitis
    All subjects: 1.03 [0.99,1.07]
    LTR subjects: 1.02 [0.98, 1.07]
    LTR females: 1.04 [1.01,1.09]
    LTR males: 1.01 [0.95,1.06]
    Asthma
    All subjects: 1.02 [0.96,1.09]
    LTR subjects: 1.04 [0.97,1.12]
    LTR females: 1.09 [0.92,1.29]
    LTR males: 1.02 [0.94,1.10]
    Asthma excluding outlier school having
    a larger proportion of Hispanics
    All subjects: 1.06 [0.97,1.16]
    LTR subjects: 1.08 [0.98,1.19]
    LTR females: 1.09 [0.96,1.24]
    LTR males: 1.08 [0.97,1.19]
    December 2009
                                    E-394
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Kumar et al. (2004,
    0898731
    
    Period of Study: 1999-2001
    
    Location: Mandi Gobindgarh and
    Morinda, Punjab State, northern India
    Outcome: Chronic respiratory
    symptoms & Spirometric ventilatory
    defect
    
    Age Groups: >1 Syr
    
    Study Design: Cross-sectional
    
    N: 3603 individuals
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Age, gender, migration,
    SES, smoking, type of cooking fuel use
    
    Dose-response Investigated? No
    Pollutant: PM,0
    
    Mean(SD): Study town 112.8 (17.9)
    
    Reference town 75.8 (2.9)
    PMio Increment:
    Low vs. High
    OR (Lower Cl, Upper Cl)
    p-value
    Chronic respiratory symptoms
    LowlOO(ref)
    High 1.5 (1.2, 1.8)
    <0.001
    Spirometric ventilatory defect
    LowlOO(ref)
    High 2.4 (2.0-2.9)
    O.001
    Reference: Leonard! et al. (2000,
    0102721
    Period of Study: 1996
    
    Location: 17 cities of Central Europe
    (Bulgaria, Czech Republic, Hungary,
    Poland, Romania, Slovakia)
    Outcome: Immune biomarkers
    
    Age Groups: 9-11
    
    Study Design: Cross-sectional
    
    N: 366 school children
    
    Statistical Analyses: Linear regression
    
    Covariates: Age, gender, parental
    smoking, laboratory of analysis, recent
    respiratory illness
    
    Dose-response Investigated? No
    
    Statistical Package: STATA
    Pollutant: PM,0
    
    Averaging Time: Annual PMio
    
    Mean(SD):PM10:65(14)
    
    Range (Min, Max):
    
    PM10:(41,96)
    
    5th, median, & 95th percentile
    
    PMi0:41,63, 90
    % Change (Lower Cl, Upper Cl)
    p-value
    PM10
    Neutrophils -5 (-33, 36)
    >20
    Total lymphocytes 20 (-6, 54);. 150
    B lymphocytes 42 (-3,107); .067
    Total T lymphocytes 30 (-2, 73); .072
    CD4+28(-10, 82);.177
    CD8+ 29 (-5,  75); .097
    CD4/CD8 7 (-20, 43)
    >20
    NK 33 (-10, 97); .157
    Total IgG 11 (-10, 38)
    >20
    Total IgM 5 (-21, 39)
    >20
    Total lgA11 (-16, 46)
    >20
    Total IgE-8 (-62, 123)
    >20
    Reference: Lichtenfels et al, (2007,
    0970411
    
    Period of Study: 2001 -2003
    Location: Sao Paulo, Brazil
    
    
    
    Reference: Lubinski, et al. (2005,
    087563)
    Period of Study: 1993-1997
    Location: Poland
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Secondary sex ratio
    
    Study Design: Retrospective Cohort
    Covariates: NR
    Statistical Analysis: Correlation
    Coefficient
    Age Groups: Infants
    
    Outcome: Pulmonary function
    TLC: total lung capacity
    ITGV: interthoracic gas volume
    ITGV%TLC: ITGV percent total lung
    cspscity
    Raw: airway resistance
    FVC: forced vital capacity
    FEV,: forced expiratory volume, 1
    sscond
    FEVi%FVC: FEV, percent forced vital
    cspscity
    PEF: peak expiratory flow
    FEF50: forced expiratory flow
    Age Groups: 18-23 males, healthy
    Study Design: Ecological cross-
    sectional study
    N: 1278 subjects
    Statistical Analyses: Multiple linear
    regression, ANOVA
    Covariates: Report unclear on whether
    or not there was covariate control, but
    may include N02 and S02
    Dose-response Investigated? No
    Pollutant: PM,0
    
    Averaging Time: Annual
    Mean (SD) Unit:
    2001: 49.8 (10.5) pg/m3
    2002: 48.5 (11.4) pg/m3
    2003: 49.4 (14.4) pg/m3
    Range (Min, Max): 31.71-60.96 pg/m3
    Copollutant (correlation): NR
    Pollutant: PM10
    Averaging Time: 12 mo
    Mean (SD):
    A: Highest Pollution Region
    Katowice 67-1 25
    Krakow 41 -49
    B: Moderate Pollution Region
    Bielsko-Biala 29-48
    Opole 18-45
    Lodz 23-38
    Warsaw 35-45
    Wroclaw 28-76
    Zagan 5-35
    C: Lowest Pollution Region
    Gizycko5-18
    Hel 12-18
    Ostroda 23-33
    Swinoujscie7-16
    Ustka 12-26
    Copollutant: N02, S02
    
    
    
    
    Increment: NR
    
    Correlation Coefficient:
    R2 = 0.7642, P = 0.1 3
    
    
    
    PM Increment: 1 pg/m3
    Slope, multiple regression
    TLC FEV,
    PM10: -0.05 PM10: 0.031
    +S02: 0.03 +S02: -0.08
    +N02:-0.06 +N02:-0.12
    ITGV FEV,%FVC
    PM10:0.01 PM10:0.00
    +S02:-0.07 +S02:-0.14
    +N02: -0.07 +N02: -0.048
    ITGV%TLC PEF
    PMi0:-0.06 PM,0:-0.18
    +S02: 0.08 +S02: 0.056
    +N02: 0.00 +N02: -0.09
    Raw FEF50
    PM10: 0.075 PM10: 0.031
    +S02:-0.08 +S02:-0.11
    +N02: 0.127 +N02:-0.04
    FVC
    PM,0: 0.045
    +S02: 0.045
    +N02:-0.14
    
    
    
    December 2009
                                    E-395
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: McConnell et al. (1999,
    0070281
    
    Period of Study: 1993
    
    Location: Southern California
    Outcome: Bronchitis, chronic cough,
    phlegm
    
    Age Groups: Children: 4th, 7th, & 10th
    graders
    
    Study Design: Cross-sectional
    
    N: 3676 people
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Age, sex, race, grade,
    health insurance
    
    Dose-response Investigated? Yes
    Pollutant: PM,0
    
    Averaging Time: Yearly avg 24 h PM10
    
    Mean (SD): 34.8
    
    Range (Min, Max): 13.0, 70.7
    Copollutant (correlation):
    N02r = 0.74
    03r = 0.32
    Acid  r = 0.54
    PM25r = 0.90
    N02r = 0.83
    03r = 0.50
    Acid  r = 0.71
    PMio Increment: 19 pg/m
    Children w/ asthma
    Bronchitis: 1.4 (1.1,1.8)
    Phlegm: 2.1 (1.4,3.3)
    Cough: 1.1 (0.8,1.7)
    Children w/wheeze, no asthma
    Bronchitis: 0.9 (0.7,1.3)
    Phlegm: 0.9 (0.6,1.4)
    Cough: 1.2 (0.9,1.8)
    Children w/ no wheeze, no asthma
    Bronchitis: 0.7 (0.4,1.0)
    Phlegm: 0.8 (0.6,1.3)
    Cough: 0.9 (0.7,1.2)
    Reference: McConnell et al. (2003,
    0494901
    Outcome: Bronchitis symptoms
    
    Age Groups: 9-19
    Period of Study: 1993-1999
                                        Study Design: Communities selected
    Location: 12 Southern CA communities  on basis of historic levels of criteria
                                        pollutants and low residential mobility.
    
                                        N: 475 children
    
                                        Statistical Analyses: 3 stage
                                        regression combined to give a logistic
                                        mixed effects model
    
                                        Covariates: Sex, ethnicity, allergies
                                        history, asthma history, SES, insurance
                                        status, current wheeze, current
                                        exposure to ETS, personal smoking
                                        status, participation in team sports, in
                                        utero tobacco exposure through
                                        maternal smoking, family history of
                                        asthma, amount of time routinely spent
                                        outside by child during 2-6 pm.
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: SAS Glimmix
                                        macro
    Pollutant: PM,0
    
    Averaging Time: 4-yr avg
    
    Mean (SD):.30.8(13.4) pg/m3
    
    Range (Min, Max): 15.7-63.5
    
    PM Component: particulate OC and EC
    
    Copollutant (correlation):
    PM25:r = 0.79
    
    PM10.25:r = 0.79
    
    Inorganic acid: r = 0.72
    
    Organic Acid: r = 0.59
    
    EC: r = 0.71
    
    OC:r = 0.70
    
    N02:r = 0.20
    
    03:r = 0.64
    PM Increment:
    
    Between community range 47.8 pg/m3
    
    Between community unit 1  pg/m3
    
    Within community 1 pg/m3
    
    OR Estimate [Lower Cl, Upper Cl]
    
    Between community per range
    1.72(0.93-3.20)1
    
    Between Community per unit 1.01(1.00-
    1.02)|
    
    Within community per unit 1.04(0.99-
    1.10)
    Reference: McConnell et al. (2002,
    0231501
    Period of Study: 1993-1998
    
    Location: 12 communities in Southern
    California (grouped into either high and
    low pollution communities)
    Outcome: Asthma (new diagnosis)
    
    Age Groups: 9-12 yr, 12-13 yr,  15-16 yr
    
    Study Design: Cohort
    
    N:3535
    
    Statistical Analyses: Multivariate
    proportion hazard model
    
    Covariates: Sex, age, ethnic origin,
    BMI, child history of allergies and
    asthma history, SES, maternal smoking,
    time spent outside, history of wheezing,
    ownership of insurance (yes/no),
    number and type of sports played
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS 8.1
    Pollutant: PM,0
    
    Averaging Time: 4 yr
    
    Mean (SD): Low pollution communities:
    21.6(3.8)
    
    High pollution communities: 43.3
    (12.0)
    
    Percentiles: Low pollution
    communities: SOth(Median): 20.8
    
    High pollution communities:
    SOth(Median): 43.3
    
    Range (Min, Max): Low pollution
    communities: 16.62, 27.3
    
    High pollution communities: 33.5, 66.9
    
    Monitoring Stations: 12
    
    Copollutant (correlation):
    PM25:r = 0.96
    N02:r = 0.65
    03
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Low PM communities: 1.0 [ref] 0 sport
    1.5 [1.0, 2.2] 1 sport
    1.2 [0.7, 1.9] 2 sports
    1.7 [0.9, 3.2] a 3 sports
    High PM communities: 1.0 [ref] 0 sport
    1.1 [0.7,1.7] 1 sport
                                                                                                               0.9
                                                                                                               2.0
        0.5,1.7] 2 sports
        1.1,3.6] >3 sports
                                                                                                               High vs. Low PMio communities: 0.8
                                                                                                               (0.6,1.0)
    
                                                                                                               Incidence-N (incidence) number of
                                                                                                               sports:
                                                                                                               Low PM communities: 49 (0.023) 0
                                                                                                               54 (0.032) 1
                                                                                                               22 (0.024) 2
                                                                                                               13 (0.033) >3
                                                                                                               High PM communities: 55 (0.021) 0
                                                                                                               36(0.021)1
                                                                                                               14(0.018)2
                                                                                                               16 (0.033) >3
    December 2009
                                    E-396
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: McConnell, et al. (2006,
    1802261
    Period of Study: 1996-1999
    Location: 12 Southern California
    communities
    Outcome: Prevalence of bronchitic
    symptoms (yrly).
    Age Groups: 10-15-yr-old
    Study Design: Longitudinal cohort
    N: 475 asthmatic children
    Statistical Analyses: Multilevel logistic
    mixed effects models.
    Covariates: Age, second-hand smoke
    Personal smoking history
    Sex, race.
    Dose-response Investigated? No
    Statistical Package: SAS with
    GLIMMIX macro
    Pollutant: PM,0
    Averaging Time: 365 days
    Percentiles: Community byyr
    (n = 48 = 12 communities • 4 yr)
    25th: NR
    SOth(Median): 3.4
    75th: NR
    Range (Min, Max):
    Community byyr (n = 48= 12
    communities' 4yr):
    (0.89, 8.7)
    Monitoring Stations:  12
    Copollutant: 03, N02, EC, OC,
    Acid vapor (acetic and formic acid)
    PM Increment: 6.1 pg/m
    OR Estimate [Lower Cl, Upper Cl]
    PM10
    Dog (n = 292): 1.60 [1.12: 2.30]
    No dog (n = 183): 0.89 [0.57:1.39]
    PMio'Dog interaction p-value: 0.02
    Cat (n = 202): 1.47 [0.96: 2.24]
    No Cat (n = 273): 1.20 [0.83:1.73]
    PMio'Cat interaction p-value: 0.41
    Neither pet (n = 112): 0.91 [0.53:1.56]
    Cat only (n = 71): 0.84 [0.42:1.66]
    Dog only (n = 161): 1.41 [0.91:2.19]
    Both pets (n = 131): 1.89 [1.15: 3.10]
    Results suggest that dog ownership, a
    source of residential exposure to
    endotoxin, may worsen the severity of
    respiratory symptoms from exposure to
    air pollutants in asthmatic children.
    Reference: Meng et al. (2007, 0932751
    Period of Study: Nov 2000 and Sep
    2001 (collection of health data)
    Location: Los Angeles and San Diego
    counties
    Outcome: Poorly controlled asthma vs.
    controlled asthma
    Age Groups: 18-64, 65+
    Study Design: Long-term exposure
    study
    Comparison of cases and controls
    N: 1,609 adults (represented individuals
    age 18+ who reported ever having been
    diagnosed as having asthma by a
    physician and had their address
    successfully geocoded)
    Statistical Analyses:  Logistic
    regression to evaluate associations
    between TD (traffic density) and annual
    avg air pollution concentrations and
    poorly controlled asthma. Used sample
    weights that adjusted for unequal
    probabilities of selection into the CHIS
    sample.
    Covariates: Age, sex, race/ethnicity,
    family federal poverty level, county,
    insurance status, delay in care for
    asthma, taking medications, smoking
    behavior, self-reported health status,
    employment, physical activity
    Dose-response Investigated? yes
    Pollutant: PM,0
    Averaging Time: 24 h over 1 yr
    Copollutant (correlation):
    03:r = -0.72
    N02:r = 0.83
    PM25:r = 0.84
    CO: r = 0.42
    TD:r = 0.14
    PM Increment: Continuous data: per
    10 pg/m3
    OR Estimate [Lower Cl, Upper Cl]
    lag:
    All Adults: 1.08 [0.82, 1.43]
    Non-Elederly Adults: 1.14 [0.84,1.55]
    Elderly: 0.84 [0.41,1.73]
    Vtomen: 1.38 [0.99,1.94]
    December 2009
                                    E-397
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Millstein et al. (2004,
    0886291
    Period of Study: Mar-Aug, 1995, and
    Sep1995-Feb1996
    Data were taken from the Children's
    Health Study
    Outcome: Wheezing & asthma
    medication use (ICD9 NR)
    Age Groups: 4th grade students,
    mostly 9 yr at the time of the study
    Study Design: Cohort Study, stratified
    into 2  seasonal groups/
    Location: Alpine, Atascadero, Lake
    Arrowhead, Lake Elsinore, Lancaster,
    Lompoc, Long Beach, Mira Loma,
    Riverside, San Dimas, Santa Maria, and  Statistical Analyses: Multilevel, mixed-
    N: 2081 enrolled, 2034 provided parent-
    completed questionnaire.
    Upland, CA
    effects logistic model.
    Covariates: Contagious respiratory
    disease, ambient airborne pollen and
    other allergens, temperature, sex, age
    race, allergies, pet cats, carpet in home,
    environmental tobacco smoke, heating
    fuel, heating system, water damage in
    home, education level of questionnaire
    signer, physician diagnosed asthma.
    Season: Mar-Aug, 1995, and Sep,
    1995toFeb,  1996
    Statistical Package: GLIMMIX SAS
    8.00 macro for generalized linear mixed
    models.
    Lags Considered: 14
    Pollutant: PM,0
    Averaging Time: Monthly means for
    PM,O.
    PM Component: Nitric acid, formic
    acid, acetic acid
    Monitoring Stations:
    1 central location in each community
    Copollutant (correlation):
    03:r = 0.76
    N02:r = 0.39
    PM25:r = 0.91
    PM Increment: IQR 13.39 pg/m
    Odds Ratio [lower Cl, Upper Cl]
    Annual
    PM10: 0.93 [0.67, 1.27]
    Mar-Aug
    PM,0:0.91 [0.46, 1.80]
    Sep-Feb
    PM10: 0.65 [0.40, 1.06]
    Reference: Neuberger et al. (2004,
    0932491
    Period of Study: Jun 1999-Jun 2000
    Location: Austria (Vienna and a rural
    area near Linz)
    Outcome: Questionnaire derived
    asthma score, and a 1-5 point
    respiratory health rating by parent
    Age Groups: 7-10 yr
    Study Design: Cross-sectional survey
    N: about 2000 children
    Statistical Analyses: Mixed models
    linear regression-used factor analysis to
    develop the "asthma score"
    Covariates: Pre-existing respiratory
    conditions, temperature, rainy days, #
    smokers in household, heavy traffic on
    residential street, gas stove or heating,
    molds, sex, age of child, allergies of
    child, asthma in other family members
    Dose-response Investigated? No
    Statistical Package: NR
    Lags Considered: 4 week avg
    (preceding interview)
    Pollutant: PM,0
    Averaging Time: 24 h
    Copollutant (correlation):
    PM2.5 (r = 0.94) in Vienna
    PM Increment: 10 pg/m
    Change in mean associated unit
    increase in PM (p-value) lag
    Respiratory Health score
    Vienna: 0.005 (p>0.05)
    lag 4 week avg
    Rural area: 0.008 (p>0.05)
    lag 4 week avg
    Asthma score
    Vienna: 0.006 (p>0.05)
    lag 4 week avg
    Rural area: -0.001 (p>0.05)
    lag 4 week avg
    Reference: Oftedal et al. (2008,
    0932021
    
    Period of Study: 2001 -2002
    Location: Oslo, Norway
    
    
    
    
    
    
    
    
    
    Outcome: Lung function (PEF, Pollutant: PM10
    FEF25%, FEF50%, FEV,, FVC)
    IQR:
    Age Groups: 9-10 yr PMlo in 1st yr of life: 10.3
    Study Design: Cross-sectional pMio |ifetime: 58
    N: 1847 children
    
    Statistical Analyses: Linear regression
    Covariates: Height, age, BMI, birth
    weight, temperature, maternal smoking,
    sex
    Dose-response Investigated? Yes
    Statistical Package:
    SPSS, STATA, S-Plus
    Lags Considered: 1-3
    PM Increment: Per IQR
    
    P (Lower Cl, Upper Cl)
    PM10in 1st yr of life
    PEF -72.5 (-122.3 to -22.7)
    FEF25% -77.4 (-133.4 to -21.4)
    FEF50% -53.9 (-102.6. to -5.2)
    FEV, -6.7 -24.1, 10.7)
    FVC 0.5 (-18.5, 19.6)
    PM,0 lifetime exposure
    PEF -66.4 (-109.5 to -23.3)
    FEF25% -61. 5 (-11 0.0 to -13.1)
    FEF50% -45.6 (-87.7 to -3.5)
    FEV, -7.3 (-22.4, 7.7)
    FVC -2.1 (-18.6, 14.4)
    
    
    December 2009
                                    E-398
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Parker et al. (2009,
    1923591
    
    Period of Study: 1999-2005
    
    Location: U.S.
    Outcome: Respiratory allergy/hayfever  Pollutant:
    Study Design: Cohort
    
    Covariates: Survey yr, age, family
    structure, usual source of care, health
    insurance, family income relative to
    federal poverty level, race/ethnicity
    
    Statistical Analysis: Logistic
    regression
    
    Statistical Package: SUDAAN
    
    Age Groups: 73,198 children aged
    3-17 yr
    Averaging Time: NR
    
    Median: 24.1 pg/m3
    
    IQR: 20.8-28.7
    Copollutant (correlation):
    Summer 03: 0.26
    S02:-0.19
    N02: 0.48
    PM25:0.51
    PM10.25:0.86
    Increment: 10|jg/m
    
    Odds Ratio (96% Cl)
    
    Single Pollutant Model, variable N
    
    Adjusted: 1.04 (0.99-1.09)
    Reference: Penard-Morand et al.
    (2005, 0879511
    
    Period of Study: Mar 1999-Oct 2000
    
    Mean concentrations of N02, S02,
    PMio, and 03 were taken from Jan
    1998-Dec2000
    
    Location: 6 French cities: Bordeaux,
    Clermont-Ferrand, Creteil, Marseille,
    Strasbourg, Reims.
    Outcome:
    Flexural dermatitis
    Asthma (493)
    Rhinoconjunctivitis
    Atopic dermatitis
    Wheeze
    Allergic rhinitis
    Atopy
    EIB (exercise-induced bronchial
    reactivity)
    Age Groups: 9-11 yr
    
    Study Design: Cross-sectional
    
    N: 9615 Children (6672 complete
    examination and questionnaire info)
    
    Statistical Analyses: Logistic
    regression
    
    Marginal Model  (GENMOD)
    
    Covariates: Age, Sex, Family history of
    allergy, Passive smoking
    
    Parental education
    
    Season: All
    
    Excluding end of spring and during
    summer for clinical examinations
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: 3 yr
    
    Mean (SD): Low concentrations: 26.9
    
    High Concentrations: 23.8
    
    Range (Min, Max):
    
    Low concentrations: 10-20
    
    High concentrations: 21.5-29.5
    
    Copollutant (correlation):
    
    \N02:r = 46
    
    S02:r=.76
    
    03:r = -.02
    
    Monitoring Stations: 16
    PM Increment: 10 pg/m3 (IQR)
    
    OR Estimate [Lower Cl, Upper Cl]:
    EIB (during exam): 1.43 (1.02-2.01)
    Flexural dermatitis (during exam):
    0.79(0.59-1.07)
    Wheeze (past yr): 1.05 (0.72-1.54)
    Asthma (past yr): 1.23 (0.77-1.95)
    Rhinoconjunctivitis (past yr):
    1.17(0.86-1.59)
    Atopic dermatitis (past yr):
    1.28(0.96-1.71)
    Asthma (lifetime): 1.32  (0.96-1.81)
    Allergic rhinitis (lifetime):
    1.32(1.04-1.68)
    Atopic dermatitis (lifetime):
    1.09(0.88-1.36)
    Atopy (lifetime): 0.98(0.80-1.22)
    Pollen:  1.14 (0.85-1.53)
    Indoor:  0.91 (0.72-1.15)
    Moulds: 1.00 (0.53-1.88)
    Highest correlated pollutant
    adjustments:
    EIB (during exam): 1.16 (0.72-1.85)
    Flexural dermatitis (during exam):
    0.930(.60-1.43)
    Wheeze (past yr): 1.31  (0.71-2.36)
    Asthma (past yr): 1.25 (0.66-2.37)
    Rhinoconjunctivitis (past yr):
    1.22(0.98-1.68)
    Atopic dermatitis (past yr):
    1.63(1.07-2.49)
    Asthma (lifetime): 1.11 (0.70-1.74)
    Allergic rhinitis (lifetime):
    1.19(0.94-1.59)
    Atopic dermatitis (lifetime):
    1.47(1.07-2.00)
    Atopy (lifetime): 0.93(0.69-1.26)
    Pollen:  1.30 (0.98-1.57)
    Indoor:  .83 (0.63-1.12)
    Molds:  1.62 (0.64-4.09)	
    Reference: Peters et al., (1999,
    0872371
    
    Period of Study: 1986-1990,1994
    
    Location: Southern California
    Outcome: Asthma, cough, bronchitis,
    wheeze
    
    Age Groups: 4th, 7th, & 10th graders
    
    Study Design: Cohort
    
    N: 3676 children
    
    Statistical Analyses: Stepwise logistic
    regression
    
    Covariates: Community, grade, race,
    sex, height, BMI,  asthma in parents,
    hay fever, health  insurance, plants in
    home, mildew in home, passive smoke
    exposure, pest infestation, carpet,
    vitamin supplements, active smoking,
    pets, gas stove, air conditioner
    
    Dose-response Investigated? Yes
    Pollutant: PM,0
    
    Averaging Time:
    24-h PM10 averaged over 1994
    
    Mean based on data collected during
    1986-1990,1994:
    Alpine 37.4, 21.3
    Atascadero 28.0, 20.7
    Lake Elsinore 59.5, 34.7
    Lake Gregory 38.3, 24.2
    Lancaster 47.0, 33.6
    LompocSO.0,13.0
    Long Beach 49.5, 38.8
    Mira Loma 84.9, 70.7
    Riverside 84.9, 45.2
    San Dimas67.0, 36.7
    Santa Maria 28.0, 29.2
    Upland 75.6, 49.0
    PM Increment: 25 pg/m
    
    OR (Lower Cl, Upper Cl) for
    respiratory illness
    Based on 1986-1990 pollutant levels
    Ever asthma 0.93 (0.76,1.13)
    Current asthma 1.09 (0.86,1.37)
    Bronchitis 0.94 (0.74,1.19)
    Cough 1.06 (0.93, 1.21)
    Wheeze 1.05 (0.89,1.25)
    Based on 1994 pollutant levels
    Ever asthma 0.87 (0.67,1.14)
    Current asthma 1.11 (0.81,1.54)
    Bronchitis 0.90 (0.65,1.26)
    Cough 1.14 (0.96, 1.35)
    Wheeze 1.01 (0.79,1.29)
    December 2009
                                     E-399
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Pierse, et al. (2006,
    0887571
    
    Period of Study: 2 yr (once in 1998
    and once in 2001—surveys)
    
    Location: Leicestershire, UK
    Outcome: Cough without a cold
    
    Night time cough
    
    Current wheeze
    
    Age Groups: 1-5yr
    
    Study Design: Cross-sectional
    (cohorts)
    
    N: 4400 children
    
    Statistical Analyses: Binomial
    generalized linear models (compared
    with likelihood ratio tests)
    
    Spatial variograms (due to the spatial
    concerns)
    
    Covariates: Age, Gender
    
    Mother/father has asthma
    
    Coal heating the home,  Smoking by
    household member in the home, Either
    parent continued education past 16 yr
    of age, Pre-term  birth, Breastfeeding,
    Gas cooking, Presence of pets, Number
    of cigarettes smoked by mother,
    Overcrowding, Single parenthood, Diet
    
    Dose-response Investigated? Yes
    (Fig. 2 shows evidence of dose-
    response effect based on surveys,
    states in discussion).
    
    Statistical Package: SAS 8.2
    
    S-Plus6.1
    Pollutant: PM,0
    
    Averaging Time: Annual PM10
    
    Mean (SD):
    1998:1.47
    
    2001:1.33
    
    Percentiles:
    25th: 1998 (.73) and 2001 (.8)
    
    75th: 1998 (1.93) and 2001 (1.84)
    PM Increment: 10 pg/rri (IQR)
    Unadjusted OR estimates [Lower Cl,
    Upper Cl]:
    Cough without cold (1998):
    1.22(1.10(01.36)
    Cough without cold (2001):
    1.46(1.27to1.68)
    Night-time cough (1998):
    1.11 (1.01 to 1.23)
    Night-time cough (2001):
    1.25 (1.09 to 1.43)
    Current wheeze (1998):
    0.99(0.89to1.10)
    Current wheeze (2001):
    1.09 (0.93 to 1.30)
    Adjusted OR Estimate [Lower Cl,
    Upper Cl]:
    Cough without cold (1998):
    1.21(1.07(01.38)
    Cough without cold (2001):
    1.56 (1.32 to 1.84)
    Night-time cough (1998):
    106 (0.94 to 1.19)
    Night-time cough (2001):
    1.25 (1.06 to 1.47)
    Current wheeze (1998):
    0.99(0.88to1.12)
    Current wheeze (2001):
    1.28 (1.04 to 1.58)
    When the child was originally
    asymptomatic in 1998:
    Unadjusted OR estimates [Lower Cl,
    Upper Cl]:
    Cough without cold (2001):
    1.68 (1.39 to 2.03)
    Night-time cough (2001):
    1.21 (1.00 to 1.46)
    Current wheeze (2001):
    1.22 (0.92 to 1.62)
    Adjusted OR Estimate [Lower Cl,
    Upper Cl]:
    Cough without cold (2001):
    1.62(1.31to2.00)
    Night-time cough (2001):
    1.19 (0.96 to 1.47)
    Current wheeze (2001):
    1.42 (1.02 to 1.97)  	
    December 2009
                                    E-400
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Qian et al. (2005, 0932831
    
    Period of Study: 1990-1992
    
    Location: Forsythe, NC
    
    Minneapolis, MN
    
    Jackson, MS.
    Outcome: FVC, FEV,, FEV,/FVC
    
    Age Groups: Middle aged (avg 56.8 yr)
    
    Study Design: Cross-sectional
    
    N: 10,240 people
    
    Statistical Analyses: Regression
    equations,  multiple linear regression
    analyses
    
    Covariates: Smoking status, recent use
    of respiratory medication, current
    respiratory symptoms, chronic lung
    diseases, field center
    
    Dose-response Investigated? No
    
    Statistical Package: SAS software,
    version 9.1
    Pollutant: PM,0
    
    Averaging Time: Annual
    
    Mean (SD): 27.9 (2.8)
    
    Percentiles: 25th: 25.8
    
    SOth(Median): 27.5
    
    75th: 30.2
    
    Range (Maximum-Minimum): 12.2
    
    Monitoring Stations:
    3 (Minneapolis, MN)
    
    5 (Jackson,  MS)
    
    and 9 (Forsythe,  NC)
    
    Copollutant: 0;
    PM Increment: 2.8 pg/rri (1 SD)
    Effect Estimate:
    In Never Smokers
    FVC IS = -0.0108, SE = 0.0026,
    p = 0001
    FEV, IS = -0.0082, SE = 0.0029,
    p = 0047
    FEV,/FVC IS = -0.0024, SE = 0.0023,
    p = 2787
    Smoking status
    Current n = 2377, FVC = -1.96,
    FEV, = -2.23, FEV,/FVC = -0.94
    Former n = 3858, FVC = -1.25,
    FEV, = -1.10, FEV,/FVC = -0.30
    Never n = 4005, FVC = -1.12,
    FEV, = -0.63, FEV,/FVC = 0.06
    Recent Use of Respiratory Medication
    Yes n = 424, FVC = -2.65,
    FEV, = -3.89, FEV,/FVC = -3.00
    No n = 9816,  FVC = -1.41,
    FEV, = -1.20, FEV,/FVC =-0.24
    Current Respiratory Symptoms
    Yes n = 4340, FVC = -1.68,
    FEV, = -1.70, FEV,/FVC =-0.63
    No n = 5900,  FVC = -1.05,
    FEV, = -0.63, FEV,/FVC = 0.05
    Chronic Lung Diseases
    Yes n = 1374, FVC = -1.95,
    FEV, = -2.31,FEV,/FVC = -1.18
    No n = 8866,  FVC = -1.35,
    FEV, = -1.10, FEV,/FVC = -0.19
    Field Center
    Forsythe, NC n = 3504,  FVC = -0.03,
    FEV, = 0.05, FEV,/FVC =-0.33
    Minneapolis, MN n = 3793, FVC = 0.50,
    FEV, = 0.54, FEV,/FVC =-0.30
    Jackson, MS  n = 2943, FVC = -0.01,
    FEV, = 0.17, FEV,/FVC = -0.32
    Reference: Rios et al. (2004, 0878001
    
    Period of Study: 1998-2000
    
    Location: the metropolitan area of Rio
    de Janiero, Brazil, Duque de Caxias
    (DC) and Seropedica (SR)
    Outcome: Wheezing, asthma, cough at Pollutant: PM
    night
    Age Groups: 13-14 yr
    
    Study Design: Cohort
    
    N: 4064 students
    
    Statistical Analyses: Cchi-squared
    
    Covariates: Sex, type of school, time of
    residence, domestic smoking, residents
    per home
    
    Dose-response Investigated? Yes
    
    Statistical Package: Epilnfo
    Averaging Time: Weekly
    measurements used to create annual
    PM estimate
    Mean (SD):
    DC
    1998:147
    1999:115
    2000:110
    Total: 124
    SR
    1998:37
    1999:31
    2000: 37
    Total: 35
    Monitoring Stations: NR
    PM Increment: High vs. Low
    Global Cut-Off Score %, p-val:
    DC
    Male: 15.0
    Female: 22.3, p < .05t
    Private School: 16.6
    Public School: 19.4, p<.05*
    <5yr residence: 20.9
    >5yr residence: 16.8
    No domestic smoking exposure: 17.6
    Domestic smoking exposure: 20.4, p <
    .05T
    <5 residents per home: 18.4
    5+ residents per home: 19.5
    SR
    Male: 12.3
    Female: 19.7, p<.05t
    Private School: 28.3, p<.05*t
    Public School: 14.7
    <5yr residence: 10.8
    >5yr residence: 16.5
    No domestic smoking exposure: 14.8
    Domestic smoking exposure: 18.3
    <5 residents per home: 15.6
    5+ residents per home: 17.4
    Notes: The Global Cut-off Score
    encompasses replies to the asthma
    component of ISAAC'S written
    questionnaire that establishes a cut-off
    from which is defined the presence of
    asthma for the Brazilian population.
    
    'Comparing the cities in the same
    control led variable
    
    tComparing the controlled variable in
    the same city
    December 2009
                                    E-401
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Rojas-Martinez et al. (2007,  Outcome: Lung function: FEVi, FVC,
    0910641                            FEF25-75%
    Period of Study: 1996-1999
    
    Location: Mexico City, Mexico
    Age Groups: Children 8 yr old at time
    of cohort recruitment
    
    Study Design: School-based "dynamic"
    cohort study
    
    N: 3170 children
    
    14,545 observations
    
    Statistical Analyses: Three-level
    generalized linear mixed models with
    unstructured variance-covariance matrix
    
    Covariates: Age, body mass index,
    height,  height by age, weekday spent
    outdoors,  environmental tobacco
    smoke, previous-day mean air pollutant
    concentration,  time since first test
    
    Dose-response Investigated? No
    
    Statistical Package: SA
    Pollutant: PM,0
    
    Averaging Time: 6 mo
    
    Mean (SD): 6-mo averaging
    
    SD:NR
    
    Mean: 75.6
    
    Percentiles: 6-mo averaging
    
    25th: 55.8
    
    SOth(Median): 67.5
    
    75th: 92.2
    
     Monitoring Stations: 5 sites for PM10,
    10 for other pollutants
    
    Copollutant:
    
    03
    
    NO,
    PM Increment: IQR 6-LC: 36.4
    Slope [Lower Cl, Upper Cl]
    Girls
    One-pollutant model
    FVC:-39 [-47:-31]
    FEV: -29 [-36: -21]
    FEF25-75%:-17[-36:1]
    FEV,/FVC: 0.12 [0.07: 0.17]
    Two-pollutant model: PM10, 6-LCS 03
    FVC: -30 [-39: -22]
    FEV:-24 [-31:-16]
    FEF25-75%: -9 [-26: 9]
    FEV,/FVC: 0.10 [0.06: 0.15]
    PM10, 6-LCS N02
    FVC:-21 [-30:-13]
    FEV:-17 [-25:-8]
    FEF25-75%: -23 [-43: -4]
    FEV,/FVC: 0.07 [0.02: 0.13]
    Multipollutant model: PM10, 6-LC, 03, &
    N02
    FVC: -14 [-23: -5]
    FEV:-11 [-20:-3]
    FEF25-75%: -7 [-27: 12]
    FEV,/FVC: 0.08 [0.03: 0.13]
    Boys
    One-pollutant model
    FVC:-33 [-41:-25]
    FEV:-27 [-34:-19]
    FEF25-75%: -18 [-34: -2]
    FEV,/FVC: 0.04 [-0.01: 0.09]
    Two-pollutant model: PM10, 6-LCS 03
    FVC:-28 [-36:-19]
    FEV:-22 [-30:-15]
    FEF25-75%:-10[-27:7]
    FEV,/FVC: 0.04 [-0.01: 0.09]
    FEV,/FVC: 0.24 [0.13: 0.34]
    PM10, 6-LCS N02
    FVC: -16 [-26: -7]
    FEV:-19 [-27:-10]
    FEF25-75%: -26 [-44: -9]
    FEVi/FVC: 0.005 [-0.06: 0.05]
    Multipollutant model PM10, 6-LC, 03, &
    N02
    FVC: -12 [-22: -3]
    FEV:-15 [-23:-6]
    FEF25-75%:-12[-30:6]
    FEV^FVC: -0.002 [-0.06: 0.05]
    Reference: Schikowski et al. (2005,
    0886371
    Period of Study: 1985-1994
    
    Location: Rhine-Ruhr Basin of
    Germany [Dortmund (1985,1990),
    Duisburg (1990), Gelsenkirchen (1986,
    1990), and Herne (1986)]
    Outcome: Respiratory symptoms &
    pulmonary function
    
    Age Groups: Age 54-55
    
    Study Design: Cross-sectional
    
    N: 4757 women
    
    Statistical Analyses: Linear & Logistic
    regressions, including random effects
    model
    
    Covariates: Age, smoking, SES,
    occupational exposure, form of heating,
    BMI, height
    
    Season: NR
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags Considered: NR
    Pollutant: PM,0
    
    Averaging Time: NR
    
    Min, P25, Median, Mean, P75, Max
    
    Annual Mean
    
    35, 40, 43, 44, 47, 53
    
    5-yr Mean
    
    39, 43, 47, 48, 53, 56
    
    Monitoring Stations: 7
    
    Copollutant (correlation): NR
    PM Increment: 7 pg/m
    
    OR (Lower Cl, Upper Cl) for asthma
    symptoms
    Annual means
    Chronic bronchitis 1.00 (0.85,1.18)
    Chronic cough 1.03 (0.87,1.23)
    Frequent cough 1.01 (0.93,1.10)
    COPD 1.37 (0.98, 1.92)
    p<0.1
    FEV, 0.953 (0.916, 0.989)
    p<0.1
    FVC 0.966 (0.940, 0.992)
    p<0.1
    FEV,/FVC 0.989 (0.978, 1.000)
    p<0.1
    Five yr means
    Chronic bronchitis 1.13 (0.95,1.34)
    Chronic cough 1.11 (0.93,1.31)
    Frequent cough 1.05 (0.94,1.17)
    COPD 1.33 (1.03, 1.72)
    p<0.1
    FEV, 0.949 (0.923, 0.975)
    p < 0.05
    FVC 0.963 (0.945, 0.982)
    p < 0.05
    FEV,/FVC 0.989 (0.980, 0.997)
    p<0.1	
    Reference: Schindler et al, (2009,      Outcome: Respiratory Symptoms
                                       Pollutant: PM,(
                                       Increment: 10|jg/m
    December 2009
                                    E-402
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    1919501
    
    Period of Study: 1991-2002
    
    Location: Switzerland
    Study Design: Prospective Cohort      Averaging Time: Annual
    Statistical Analysis: Logistic
    Regression Model
    
    Age Groups: Adults, 18-60 yr of age at
    start of study
    
    Covariates: Sex, age, level of
    education, Swiss citizenship, BMI,
    parental smoking, parental history of
    asthma/atopy, early respiratory
    infection, smoking status, pack yr, daily
    number of cigarettes, yr since smoking
    cessation, passive smoking in
    general/at work, occupational exposure
    to airbourne irritants
    Mean (SD) Unit:
    
    Range (Min, Max):
    
    Copollutant (correlation): NR
    Odds Ratio (96%CI) of reporting
    symptoms at second interview
    Entire Sample, New Reports
    Regular Cough: 0.77 (0.62-0.97)
    Regular Phlegm: 0.74 (0.56-0.99)
    Chronic Cough or Phlegm:
    0.78 (0.62-0.98)
    Wheezing: 1.01 (0.74-1.39)
    Wheezing with Dyspnea:
    0.70(0.49-1.01)
    Wheezing without Cold:
    1.06(0.76-1.50)
    Entire Sample, Persistent Reports
    Regular Cough: 0.55 (0.39-0.78)
    Regular Phlegm: 0.82 (0.52-1.33)
    Chronic Cough or Phlegm:
    0.67(0.40-1.15)
    Wheezing: 0.50 (0.32-0.80)
    Wheezing with Dyspnea:
    0.59(0.30-1.23)
    Wheezing without Cold: 0.61- (0.35-
    1.12)
    Persistent Non-Smokers, New Reports
    Regular Cough: 0.86 (0.63-1.19)
    Regular Phlegm: 0.70 (0.49-0.99)
    Chronic Cough or Phlegm:
    0.71 (0.52-0.99)
    Wheezing: 0.93 (0.60-1.46)
    Wheezing with Dyspnea:
    0.77(0.50-1.20)
    Wheezing without Cold:
    1.11(0.66-1.92)
    Persistent Non-Smokers,
    Persistent Reports
    Regular Cough: 0.28 (0.14-0.60)
    Regular Phlegm: 0.87 (0.43-1.84)
    Chronic Cough or Phlegm:
    0.35(0.16-0.81)
    Wheezing: 0.53 (0.28-1.08)
    Wheezing with Dyspnea:
    0.76(0.30-2012)
    Wheezing without Cold:
    0.61 (0.26-1.52)
    Gender-specific odds ratio (96%CI)
    of reporting symptoms at second
    interview
    New Reports
    Regular Cough, p = 0.73
    Men: 0.75 (0.53-1.06)
    Women: 0.81 (0.58-1.15)
    Regular Phlegm, p = 0.41
    Men: 0.85 (0.60-1.20)
    Women: 0.68 (0.46-1.00)
    Chronic Cough or Phlegm: 0.36
    Men: 0.87 (0.63-1.21)
    Women: 0.71 (0.51-0.97)
    Wheezing, p = 0.20
    Men: 0.83 (0.57-1.20)
    Women: 1.20 (0.78-1.87)
    Wheezing with Dyspnea, p = 0.11
    Men: 0.56 (0.36-0.87)
    Women: 1.00.57-1.842
    Wheezing without Cold, p = 0.43
    Men: 0.95 (0.63-1.42)
    Women: 1.25 (0.72-2.17)
    Persistent Reports
    Regular Cough, p = 0.02
    Men: 0.75 (0.48-1.18)
    Women: 0.31 (0.17-0.56)
    Regular Phlegm, p = 0.33
    Men: 0.65 (0.37-1.12)
    Women: 1.04 (0.47-2.34)
    Chronic Cough or Phlegm: 0.47
    Men: 0.68 (0.39-1.20)
    Women: 0.47 (0.20-1.11)
    Wheezing, p = 0.29
    Men: 0.34 (0.17-0.72)	
    December 2009
                                    E-403
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                Women: 0.57 (0.32-1.01)
                                                                                                                Wheezing with Dyspnea, p = 0.63
                                                                                                                Men: 0.56 (0.16-1.95)
                                                                                                                Women: 0.37 (0.13-1.05)
                                                                                                                Wheezing without Cold, p = 0.57
                                                                                                                Men: 0.34 (0.12-0.91)
                                                                                                                Women: 0.49 (0.21-1.15)
                                                                                                                Odds Ratio (96%CI) of reporting
                                                                                                                symptoms at second interview with
                                                                                                                additional adjustment for annual
                                                                                                                outdoor PM exposure at baseline
                                                                                                                Entire Sam pie
                                                                                                                Regular Cough, p = 0.0003
                                                                                                                New Reports: 0.77  (0.61-0.97)
                                                                                                                Persistent Reports: 0.55 (0.39-0.78)
                                                                                                                Regular Phlegm, p  = 0.13
                                                                                                                New Reports: 0.77  (0.59-1.02)
                                                                                                                Persistent Reports: 0.79 (0.46-1.33)
                                                                                                                Chronic Cough or Phlegm, p = 0.02
                                                                                                                New Reports: 0.78  (0.62-0.98)
                                                                                                                Persistent Reports: 0.64 (0.40-1.02)
                                                                                                                Wheezing, p = 0.002
                                                                                                                New Reports: 0.91  (0.63-1.33)
                                                                                                                Persistent Reports: 0.47 (0.31-0.72)
                                                                                                                Wheezing with Dyspnea, p = 0.03
                                                                                                                New Reports: 0.65  (0.43-0.98)
                                                                                                                Persistent Reports: 0.55 (0.28-1.10)
                                                                                                                Severe Wheezing,  p = 0.28
                                                                                                                New Reports: 0.96  (0.66-1.40)
                                                                                                                Persistent Reports: 0.62 (0.34-1.12)
                                                                                                                Non-Smokers
                                                                                                                Regular Cough, p< 0.001
                                                                                                                New Reports: 0.87  (0.63-1.19)
                                                                                                                Persistent Reports: 0.29 (0.16-0.52)
                                                                                                                Regular Phlegm, p  = 0.07
                                                                                                                New Reports: 0.70  (0.50-0.99)
                                                                                                                Persistent Reports: 0.67 (0.34-1.33)
                                                                                                                Chronic Cough or Phlegm, p = 0.008
                                                                                                                New Reports: 0.72  (0.52-0.99)
                                                                                                                Persistent Reports: 0.38 (0.17-0.84)
                                                                                                                Wheezing, p = 0.07
                                                                                                                New Reports: 0.87  (0.52-1.48)
                                                                                                                Persistent Reports: 0.48 (0.25-0.91)
                                                                                                                Wheezing with Dyspnea, p = 0.36
                                                                                                                New Reports: 0.76  (0.48-1.19)
                                                                                                                Persistent Reports: 0.70 (0.27-1.82)
                                                                                                                Severe Wheezing,  p = 0.57
                                                                                                                New Reports: 1.11  (0.64-1.93)
                                                                                                                Persistent Reports: 0.64 (0.26-1.54)
    Reference: Sharma et al. (2004,
    1569741
    Period of Study: Nov 2002-Apr 2003
    
    Location: 3 sections in Kanpur City,
    India:
    1) Indian Institute of Technology Kanpur
    (IITK)
    
    2) Vikas Nagar (VN)
    
    3) Juhilal Colony (JC)
    Outcome: Lung function
    
    Age Groups: 20-55 yr
    
    Study Design: Cohort
    
    N: 91 people
    
    Statistical Analyses: Linear regression
    
    Covariates: NR
    
    Season: Fall, Wnter, spring
    
    Dose-response Investigated? No
    
    Statistical Package: Microsoft Excel
    
    Lags Considered: 1-day lag & 5-day
    ma
    Pollutant: PM10
    
    Averaging Time: 24 h
    Mean (SD):
    IITK 184 (40)
    VN 295 (58)
    JC 293 (90)
    
    PM Component: Lead, Nickel,
    Cadmium, Chromium, Iron, Zinc
    Benzene soluble fraction (includes
    polycyclic aromatic hydrocarbons
    [PAHs])
    
    Copollutant (correlation):
    APEF = mean daily deviations in PEF
    PM10-APEF: (-0.52)
    PMio-PM25:(0.67)
    PM10-PM10 (1-day lag): (0.45)
    PMio-PM25 (1-day lag): (0.46)
    PM Increment: 1 pg/m
    
    APEF (difference or change in peak
    expiratory flow)
    
    -0.0318 L/min
    December 2009
                                    E-404
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Tager et al. (2005, 0875381
    
    Period of Study: Apr 2000-Jun 2000,
    Feb2001-Jun2001,
    
    Feb2002-Jun2002
    
    Location:
    
    Los Angeles, California
    
    San Francisco, California
    Outcome: Lung Function (FEVi, FVC,
    PEFR, FEF75, FEF25-75,
    FEF25-75/FVC ratio)
    
    Age Groups: 16-21+ y/o
    
    College Freshman
    
    Study Design: Retrospective cohort
    
    N: 255 students
    
    108 Men(M)
    
    147V\fomen(W)
    
    Statistical Analyses:  Multivariate
    Linear Regression
    
    Covariates: Sex, height, weight, area
    of residence, age, race, ETS exposure,
    respiratory disease history
    
    Dose-response Investigated? No
    Pollutant: PM,0
    
    Averaging Time: Cumulative lifetime
    exposure
    Median:
    Prior to 1987: M: 73
    W:71
    1987 and later: M: 36
    W:34
    Lifetime: M: 48
    W:45
    Range (Min, Max):
    Prior to 1987: M: 34,117
    W:31,124
    1987 and later: M: 18,  68
    W: 20, 61
    Lifetime: M: 21, 80
    W: 18, 71
    Monitoring Stations:  Between 1 and 3
    
    Copollutant (correlation):
    03 prior to 1987: r = 0.68
    031987 and later: r = 0.81
    03-Lifetime:r = 0.57
    PM Increment: 1 pg/m
    
    Parameter Estimates (SD)
    
    (Lifetime PM10, Interaction PM10
    
    FEF25-75/FVC)
    
    LnFEF75:
    
    M: -0.009 (0.0009), 0.009 (0.007)
    
    W:-0.010 (0.0007), 0.008(0.0005)
    Reference: Tamura et a. (2003,
    0874451
    Period of Study: 1998-1999
    
    Location: Bangkok, Thailand
    Outcome: Non-specific respiratory
    disease (Chronic bronchitis, acute
    bronchitis, bronchial asthma, dyspnea
    and wheezing)
    
    Age Groups: Adults
    
    Study Design: Cross-sectional
    
    N: 1603 policemen
    
    Statistical Analyses: Multiple logistic
    regression
    
    Covariates: Age, smoking status
    
    Dose-response Investigated? Yes
    
    Statistical Package: SPSS
    Pollutant: PM10
    
    Averaging Time: 24 h
    
    Mean (SD):
    
    Heavily Polluted 80-190
    
    Moderately Polluted 60-69
    
    Control 59
    
    Monitoring Stations: 13
    PM Increment: Heavily Polluted vs.
    Moderately Polluted vs. Control
    
    Number and Prevalence (%) of
    respiratory disease among heavily
    polluted, moderately polluted, and
    control areas.
    Heavily Polluted
    Chronic bronchitis 16 (3.0)
    Acute bronchitis 19 (3.5)
    Bronchial asthma 5 (0.9)
    Dyspnea & wheezing 49 (9.2)
    Anyl of above 69 (13.0)
    Persistent cough 11  (2.1)
    Persistent phlegm 27 (1.3)
    CoughS phlegm 6 (1.1)
    Moderately Polluted
    Chronic bronchitis 8 (2.4)
    Acute bronchitis 12 (9.0)
    Bronchial asthma 2 (0.6)
    Dyspnea & wheezing 23 (6.8)
    Any 1 of above 37 (10.9)
    Persistent cough 1 (0.3)
    Persistent phlegm 11 (3.3)|
    Cough & phlegm 1 (0.3)
    Control
    Chronic bronchitis 6 (1.9)
    Acute bronchitis 11 (3.3)
    Bronchial asthma 0 (0.0)
    Dyspnea S wheezing 23 (7.2)
    Anyl of above 31 (9.4)
    Persistent cough 1 (0.3)
    Persistent phlegm 8 (2.4)
    Cough & phlegm 1 (0.3)	
    December 2009
                                    E-405
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Wheeler and Ben-Schlomo
    (2005, 1887661
    
    Period of Study: 1995-1997
    
    Location: England
    Outcome: FEVi
    
    Age Groups: 16-79yr
    
    Study Design: Data from Health
    Survey for England were coupled
    geographically with air pollution
    measurements on a 1 km grid.
    
    N: 26,426 households with 39,251
    adults
    
    Statistical Analyses: Logistic
    regression, least squares regression
    
    Covariates: Age, sex, height, body
    mass index, smoking status,  household
    passive smoke exposure, inhaler use in
    the previous 24-h, doctor diagnosis of
    asthma.
    
    Dose-response Investigated? No
    Pollutant: PM,0
    
    Averaging Time: 1996 annual mean
    
    Mean (SD): 23.95 (3.58)
    
    Range (Min, Max):  17.87-43.37
    P (96%CI) for Height-age
    standardized FEV1 by ambient air
    quality index
    
    p-value
    
    Male
    
    Good (ref)
    
    Poor-0.023 (-0.030 to-0.016)
    
    O.001
    
    Female
    
    Good (ref)
    
    Poor-0.019 (-0.026 to-0.013)
    
    O.001
    Reference: Zhang et al., (2002,
    0348141
    Period of Study: 1993-1996
    
    Location: 4 Chinese cities (urban and
    suburban location in each city):
    Guangzhou, Wuhan,  Lanzhou,
    Chongqing
    Outcome: Interview-self reports of
    symptoms: Wheeze (ever wheezy when
    having a cold)
    
    Asthma (diagnosis by doctor)
    
    Bronchitis (diagnosis by doctor),
    Hospitalization due to respiratory
    disease (ever)
    
    Persistent cough (coughed for at least 1
    month per yr with or apart from colds)
    
    Persistent phlegm (brought up phlegm
    or mucus from the chest for at least 1
    month per yr with or apart from colds)
    
    Age Groups: Elementary school
    students
    
    age range: 5.4-16.2
    
    Study Design: Cross-sectional
    
    N: 7,557 returned questionnaires
    
    7,392 included in first stage of analysis
    
     Statistical Analyses: 2-stage
    regression approach: Calculated odds
    ratios and 95% CIs of respiratory
    outcomes and covariates Second stage
    consisted of variance-weighted linear
    regressions that examined associations
    between district-specific adjusted
    prevalence rates and district-specific
    ambient levels of each pollutant.
    
    Covariates: Age, gender, breast-fed,
    house type, number of rooms, sleeping
    in own or shared room, sleeping in own
    or shared bed, home coal use,
    ventilation device used, homes
    smokiness during cooking, eye irritation
    during cooking, parental smoking,
    mother's education level, mother's
    occupation, father's occupation,
    questionnaire respondent, yr of
    questionnaire administration, season of
    questionnaire administration, parental
    asthma prevalence
    Pollutant: PM10
    
    Averaging Time: 2 yr
    
    Mean (SD): 151 (56)
    
    IQR: 87
    
    Range (Min, Max):
    
    Gives range (max.-min.):
    
    80
    
    Monitoring Stations:
    
    2 types: municipal monitoring stations
    over a period of 4 yr (1993-1996)
    
    Schoolyards of participating children
    over a period of 2 yr (1995-1996)
    PM Increment: Interquartile range
    corresponded to 1 unit of change.
    
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    
    Association between persistent phlegm
    and PM10: 3.21 (1.55, 6.67)
    
    p < 0.05
    
    Between and within city modeled ORs,
    scaled to interquartile range of
    concentrations for each pollutant.
    
    No associations between any type of
    respiratory outcome and PMi0
    
    When scaled to an increment of
    50 pg/m3 of PM10, ORs were:
    
    Wheeze: 1.07
    
    Asthma: 1.18
    
    Bronchitis: 1.53
    
    Hospitalization: 1.17
    
    Persistent cough: 1.20
    
    Persistent phlegm: 1.95
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                                     E-406
    

    -------
    Table E-23.    Long-term exposure - respiratory morbidity outcomes - PMio2s-
                  Study
                                              Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Chattopadhyay et al. (2007,  Outcome: pulmonary function tests
                                       (respiratory impairments)
    147471
    
    Period of Study: NR
    
    Location: Three different points in
    Kolkata, India: North, South, and
    Central
                                       Age Groups: All ages
    
                                       Study Design: Cross-sectional
    
                                       N: 505 people studied for PFT
    
                                       total population of Kolkata not given
    
                                       Statistical Analyses:
    
                                       Frequencies
    
                                       Covariates: Meteorologic data (i.e.
                                       temperature, wind direction, wind
                                       speed, and  humidity)
    
                                       Dose-response Investigated? No
    Pollutant: PM<3.3-0.4
    
    Averaging Time: 8 h
    
    Mean (SD):
    
    North Kolkata: 266.1
    
    Central Kolkata: 435.3
    
    South Kolkata: 449.1
    
    Unit (i.e. pg/m3):  pg/m3
    
    Monitoring Stations: 1
    
    Copollutant (correlation):
    
    PM10
    
    PM<10-3.3
    PM Increment: NR
    
    Respiratory impairments (SD):
    North Kolkata
    Male(n=137)
    Restrictive: 4 (2.92)
    Obstructive: 5 (3.64)
    Combined Res. And Obs.: 6 (4.37)
    Total: 15 (10.95)
    Female (n=152)
    Restrictive: 3 (1.97)
    Obstructive: 5 (3.28)
    Combined Res. And Obs.: 0
    Total: 8 (5.26)
    Total (n=289)
    Restrictive: 7 (2.42)
    Obstructive: 10 (3.46)
    Combined Res. And Obs.: 6 (2.07)
    Total: 23 (7.96)
    
    Central Kolkata
    Male (n=44)
    Restrictive: 6 (13.63)
    Obstructive: 1 (2.27)
    Combined Res. And Obs.:1 (2.27)
    Total: 8 (18.18)
    Female (n=50)
    Restrictive: 3 (6.00)
    Obstructive: 2 (4.00)
    Combined Res. And Obs.: 0
    Total: 5 (10.00)
    Total (n=94)
    Restrictive: 9 (9.57)
    Obstructive: 3 (3.19)
    Combined Res. And Obs.: 1 (1.06)
    Total: 13 (13.82)
    
    South  Kolkata
    Male (n=52)
    Restrictive:! (1.92)
    Obstructive: 2 (3.84)
    Combined Res. And Obs.: 3 (5.76)
    Total: 6 (11.53)
    Female (n=70)
    Restrictive: 2 (2.85)
    Obstructive:! (1.42)
    Combined Res. And Obs. :0
    Total: 3 (4.28)
    Total (n=122)
    Restrictive: 3 (2.45)
    Obstructive: 3 (2.45)
    Combined Res. And Obs.: 3 (2.45)
    Total: 9 (7.37)     	
    December 2009
                                                                       E-407
    

    -------
                  Study
                                                Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chattopadhyay et al. (2007,  Outcome: Pulmonary function tests
    '                                    (respiratory impairments)
    147471
    
    Period of Study: NR
    
    Location: Three different points in
    Kolkata, India: North, South, and
    Central
                                        Age Groups: All ages
    
                                        Study Design: Cross-sectional
    
                                        N: 505 people studied for PFT
    
                                        Total population of Kolkata not given
    
                                        Statistical Analyses: Frequencies
    
                                        Covariates: Meteorologic data (i.e.
                                        temperature, wind direction, wind
                                        speed, and humidity)
    
                                        Dose-response Investigated? No
    Pollutant: PM<10-3.3
    
    Averaging Time: 8 h
    
    Mean (SD):
    
    North Kolkata: 269.8
    
    Central Kolkata: 679.2
    
    South Kolkata: 460.1
    
    Monitoring Stations:  1
    
    Copollutant (correlation):
    
    PM10
    
    PMO.3-0.
    PM Increment: NR
    
    Respiratory impairments (SD):
    North Kolkata
    Male(n=137)
    Restrictive: 4 (2.92)
    Obstructive: 5 (3.64)
    Combined Res. And Obs.: 6 (4.37)
    Total: 15 (10.95)
    Female (n=152)
    Restrictive: 3 (1.97)
    Obstructive: 5 (3.28)
    Combined Res. And Obs. :0
    Total: 8 (5.26)
    Total (n=289)
    Restrictive: 7 (2.42)
    Obstructive: 10 (3.46)
    Combined Res. And Obs.: 6 (2.07)
    Total: 23 (7.96)
    
    Central Kolkata
    Male (n=44)
    Restrictive: 6 (13.63)
    Obstructive: 1  (2.27)
    Combined Res. And Obs.: 1 (2.27)
    Total: 8 (18.18)
    Female (n=50)
    Restrictive: 3 (6.00)
    Obstructive: 2 (4.00)
    Combined Res. And Obs.: 0
    Total: 5 (10.00)
    Total (n=94)
    Restrictive: 9 (9.57)
    Obstructive: 3 (3.19)
    Combined Res. And Obs.: 1 (1.06)
    Total: 13 (13.82)
    
    South Kolkata
    Male (n=52)
    Restrictive:! (1.92)
    Obstructive: 2 (3.84)
    Combined Res. And Obs.: 3 (5.76)
    Total: 6 (11.53)
    Female (n=70)
    Restrictive: 2 (2.85)
    Obstructive:!  (1.42)
    Combined Res. And Obs. :0
    Total: 3 (4.28)
    Total (n=122)
    Restrictive: 3 (2.45)
    Obstructive: 3 (2.45)
    Combined Res. And Obs.: 3 (2.45)
    Total: 9 (7.37)     	
    Reference: Dales et al., (2008,
    1563781
    
    Period of Study: Location: Windsor,
    ON
                                        Outcome: Pulmonary function and
                                        inflammation
    
                                        Age Groups: Grades 4-6
    Pollutant: PM10.25
    
    Averaging Time: Annual
    
    Mean: 7.25
    
    5th: 6.02
                                        Study Design: Cross-sectional
                                        prevalence design
    
                                        Statistical Analyses: Multivariate linear 95th: 8.23
                                        re9ression                           Copollutant:
                                        Covariates:  Ethnic background,        SQ
                                        smokers at home, pets at home, acute      2
                                        respiratory illness,  medication use      NO,
    Increment: Tertiles of exposure
    FEV,:
    <7.04: 2.18 ±0.01
    7.04-7.53:2.19 + 0.02
    >7.53: 2.14 ±0.01
    FVC:
    <7.04: 2.52 ± 0.02
    7.04-7.53: 2.53 ±0.02
    >7.53: 2.48 ±0.02
    eNO:
    <7.04:15.48±0.63
    7.04-7.53:16.73 ±0.76
    >7.53:16.59 ±0.79
    December 2009
                                                                         E-408
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Gauderman et al. (2000,
    0125311
    
    Period of Study: 1993-1997
    
    Location: Southern California
    Outcome: FVC, FEV,, MMEF, FEF75   Pollutant: PMi0.2.5
    
    Age Groups: Fourth, seventh, or tenth  Averaging Time: 24-h avg PM10 &
    graders                             annual avg of 2-wk avg PM2 5
    
    Study Design: Cohort                Mean (SD): PM10.2.5 25.6
    
    N: 3035 subjects                     Copollutant (correlation):
    
    Statistical Analyses: Linear regression 03 r = -0.29
    
    Covariates: Height, weight, BMI,       N02 r = 0.44
    asthma, smoking,  exercise, room
    temperature, barometric pressure       Inor9'Acld ' = a43
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS
                                       Increment: 25.6 pg/m
    
                                       % Change (Lower Cl, Upper Cl)
                                       PM10.25-4th grade
                                        FVC-0.57 (-1.20 to-0.06)
                                        FEV,-0.90 (-1.71 to-0.09)
                                        MMEF-1.37 (-2.57 to-0.15)
                                        FEF75-1.62 (-3.24, 0.04)
                                       PMio.25-7th grade
                                        FVC-0.35 (-1.02, 0.31)
                                        FEV,-0.49 (-1.21, 0.24)
                                        MMEF-0.64 (-2.83, 1.60)
                                        FEF75-0.74 (-2.65, 1.20)
                                       PMi0.25-10th grade
                                        FVC-0.17 (-1.32, 0.99)
                                        FEV,-0.68 (-2.15, 0.81)
                                        MMEF-1.41 (-5.85,3.25)
                                        FEF75-2.32 (-6.60, 2.17)
    Reference: Gauderman et al. (2002,
    0260131
    Period of Study: 1996-2000
    
    Location: Southern California
    Outcome: Lung function development:
    FEV,, maximal mid-expiratory flow
    (MMEF)
    
    Age Groups: Fourth grade children
    (avg age = 9.9 yr)
    
    Study Design: Cohort study
    
    N: 1678 children, 12 communities
    
    Statistical Analyses: Mixed model
    linear regression
    
    Covariates: Height, BMI, doctor-
    diagnosed asthma and cigarette
    smoking in previous yr, respiratory
    illness and exercise on day of test,
    interaction of each of these variables
    with sex, barometric pressure,
    temperature at test time, indicator
    variables for field technician and
    spirometer
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS (10)
    Pollutant: PMi0.25
    
    Averaging Time: Annual 24-h avg
    
    Mean (SD): The avg levels were
    presented in an online data supplement
    (FigE1)
    
     Monitoring Stations: 12
    
    Copollutant (correlation):
    
    03(10AMto6PM)r = 0.10
    
    03r = -0.31
    
    N02r = 0.46
    
    Acid vapor r = 0.63
    
    PM10r = 0.95
    
    PMi0.25r = 0.81
    
    EC r = 0.71
    
    OCr = 0.96
    PM Increment: 29.1 pg/m
    
    Association Estimate:
    
    PM10.2 5 was not correlated with any of
    the pulmonary function tests that were
    analyzed
    Reference: Leonard! et al. (2000,
    0102721
    Period of Study: 1996
    Location: 17 cities of Central Europe
    (Bulgaria, Czech Republic, Hungary ,
    Poland, Romania, Slovakia)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Immune biomarkers
    
    Age Groups: 9-11
    Study Design: Cross-sectional
    N: 366 school children
    Statistical Analyses: Linear regression
    Covariates: Age, gender, parental
    smoking, laboratory of analysis, recent
    respiratory illness
    Dose-response Investigated? No
    
    Statistical Package: STATA
    
    
    
    
    
    
    
    
    
    
    
    
    Pollutant: PM10.25
    
    Averaging Time: Subtracting PM25
    from PM10 provides avg PM10.25
    Mean(SD):PM10.25:20(5)
    Range (Min, Max):
    DM • MO QQ\
    PMio-2.5. (12, 38)
    5th, median, & 95th percentile
    PM10.25: 12, 19, 29
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    % Change (Lower Cl, Upper Cl)
    p-value
    PM,0-2.5
    Neutrophils 1 (-27, 38)
    >20
    Total lymphocytes 8 (-15, 38)
    >20
    B lymphocytes 22 (-16, 76)
    >20
    Total T lymphocytes 2 (-25, 37)
    -> on
    '".ZU
    CD4+-1 (-30,41)
    >20
    CD8+3J-25, 41)
    >20
    CD4/CD8 0 (-23, 30)
    >20
    NK1 (-33,51)
    >20
    TotallgG-3(-21, 18)
    >20
    Total IgM 19 (-9, 55)
    >20
    Total IgA 16 (-12, 52)
    >20
    Total IgE -29 (-70, 70)
    >20
    December 2009
                                    E-409
    

    -------
                  Study
           Design & Methods
            Concentrations1
                                           Effect Estimates (95% Cl)
    Reference: McConnell et al. (2003,
    0494901
    Outcome: Bronchitic symptoms
    Age Groups: 9-19
    Period of Study: 1993-1999
                                        Study Design: Communities selected
    Location: 12 Southern CA communities  on basis of historic levels of criteria
                                        pollutants and low residential mobility.
                                        N: 475 children
                                        Statistical Analyses: 3 stage
                                        regression combined to give a logistic
                                        mixed effects model
                                        Covariates: Sex, ethnicity, allergies
                                        history, asthma history, SES, insurance
                                        status, current wheeze, current
                                        exposure to ETS, personal smoking
                                        status, participation in team sports,  in
                                        utero tobacco exposure through
                                        maternal smoking, family history of
                                        asthma, amount of time routinely spent
                                        outside by child during 2-6 pm.
                                        Dose-response Investigated? No
                                        Statistical Package: SAS Glimmix
                                        macro
    Pollutant: PM10.2.5
    Averaging Time: 4-yr avg
    Mean (SD): 17.0(6.4)
    Range (Min, Max): 10.2-35.0
    Copollutant (correlation):
    PM25:r = 0.24
    PMi0:r = 0.79
    Inorganic acid: r = 0.38
    Organic Acid: r = 0.35
    EC: r = 0.30
    OC:r = 0.27
    N02:r = -0.22
    03:r = 0.29
                                        PM Increment: Between community
                                        range 24.8 pg/m3
                                        Between community unit 1 pg/m3
                                        Within community 1 pg/m3
                                        OR Estimate [Lower Cl, Upper Cl]
                                        Between community per range
                                        1.38(0.65-2.92)
                                        Between Community per unit
                                        1.01(0.98-1.04)
                                        Within community per unit
                                        1.02(0.95-1.10)
    Reference: Millstein et al. (2004,
    0886291
    Period of Study: Mar-Aug, 1995, and
    Sep1995-Feb1996
    Data were taken from the Children's
    Health Study
    Outcome: Wheezing & asthma
    medication use
    Age Groups: 4th grade students,
    mostly 9 yr at the time of the study
    Study Design: Cohort Study, stratified
    into 2  seasonal groups/
    Pollutant: PM10.2.5
    Averaging Time: monthly
    PM Component: Nitric acid, formic
    acid, acetic acid
                                        PM Increment: IQR 11.44 pg/m3
                                        Odds Ratio [lower Cl, Upper Cl]
                                        Annual
                                        PM10.25: 0.96 [0.74, 1.25]
    Location: Alpine, Atascadero, Lake
    Arrowhead, Lake Elsinore, Lancaster,
    Lompoc, Long Beach, Mira Loma,
    Riverside, San Dimas, Santa Maria, and  Statistical Analyses: Multilevel, mixed-
    N: 2081 enrolled, 2034 provided parent-
    completed questionnaire.
    Upland, CA
    effects logistic model.
    Covariates: Contagious respiratory
    disease, ambient airborne pollen and
    other allergens, temperature, sex, age
    race, allergies, pet cats, carpet in home,
    environmental tobacco smoke, heating
    fuel, heating system, water damage in
    home, education level of questionnaire
    signer, physician diagnosed asthma.
    Season: Mar-Aug, 1995, and Sep,
    1995toFeb,  1996
    Statistical Package: SAS 8.00
    Lags Considered: 14
    Monitoring Stations: 1 central location
    in each community                    Mar-Aug
                                        PMio.25: 0.93 [0.54, 1.59]
                                        Sep-Feb
                                        PM10.25: 0.68 [0.46, 1.01]
    Copollutant (correlation):
    N02:r = 0.29
    03:r = 0.77
                                                                            PM25:r = -0.08
    Reference: (Parker et al., 2009,
    192369)
    Period of Study: 1999-2005
    Location: U.S.
    Outcome: Respiratory allergy/hayfever
    Study Design: Cohort
    Covariates: Survey yr, age, family
    structure, usual source of care, health
    insurance, family income relative to
    federal poverty level, race/ethnicity
    Statistical Analysis: Logistic
    regression
    Statistical Package: SUDAAN
    Age Groups: 73,198 children aged
    3-17 yr
    Pollutant: PM10.25
    Averaging Time: NR
    Median:11.2|jg/m3
    IQR: 8.2-15.2
    Copollutant (correlation):
    Summer
    03:0.16
    S02: -0.33
    N02: 0.29
    PM25:0.02
    PMi0:0.86
                                        Increment: 10|jg/m
                                        Odds Ratio (96% Cl)
                                        Single Pollutant Model, variable N
                                        Adjusted: 1.01 (0.95-1.07)
                                        Single Pollutant Model, constant N
                                        Adjusted: 1.13 (1.04-1.46)
                                        Multi-pollutant Model: 1.16 (1.06-1.24)
    December 2009
                                    E-410
    

    -------
                  Study
    Design & Methods
    Concentrations1
                                                                                 Effect Estimates (95% Cl)
    Reference: Zhang et al. (2002,
    0348141
    Period of Study: 1993-1996
    
    Location: 4 Chinese cities (urban and
    suburban location in each city):
    Guangzhou, Wuhan, Lanzhou,
    Chongqing
    Outcome: Interview-self reports of
    symptoms: Wheeze (ever wheezy when
    having a cold)
    
    Asthma (diagnosis by doctor)
    
    Bronchitis (diagnosis by doctor),
    Hospitalization due to respiratory
    disease (ever)
    
    Persistent cough (coughed for at least 1
    month per yr with or apart from colds)
    
    Persistent phlegm (brought up phlegm
    or mucus from the chest for at least 1
    month per yr with or apart from colds)
    
    Age Groups: Elementary school
    students
    
    age range: 5.4-16.2
    
    Study Design: Cross-sectional
    
    N: 7,557 returned questionnaires
    
    7,392 included in first stage of analysis
    
     Statistical Analyses: 2-stage
    regression approach:  Calculated odds
    ratios and 95% CIs of respiratory
    outcomes and covariates Second stage
    consisted of variance-weighted linear
    regressions that examined associations
    between district-specific adjusted
    prevalence rates and district-specific
    ambient levels of each pollutant.
    
    Covariates: Age, gender, breast-fed,
    house type, number of rooms, sleeping
    in own or shared room, sleeping in own
    or shared bed, home coal use,
    ventilation device used, homes
    smokiness during cooking, eye irritation
    during cooking, parental smoking,
    mother's education level, mother's
    occupation,  father's occupation,
    questionnaire respondent, yr of
    questionnaire administration, season of
    questionnaire administration, parental
    asthma prevalence
                                 Pollutant: PM10.2.5
    
                                 Averaging Time: 2 yr
    
                                 Mean (SD): 59 (28)
    
                                 Percentiles:
                                 25th: NR
    
                                 SOth(Median): NR
    
                                 75th: NR
    
                                 IQR: 42
    
                                  Range (Min, Max):
    
                                 Gives range (max.-min.): 80
    
                                 Monitoring Stations:
    
                                 2 types: municipal  monitoring stations
                                 over a period of 4 yr (1993-1996)
    
                                 Schoolyards of participating children
                                 over a period of 2 yr (1995-1996)
                                PM Increment: Interquartile range
                                corresponded to 1 unit of change.
    
                                RR Estimate [Lower Cl, Upper Cl]
                                Association between bronchitis and
                                PM10.25: 2.20 (1.14, 4.26)
    
                                p < 0.05
    
                                Association between persistent cough
                                and PM10.25:1.46 (1.12,1.90)
    
                                p < 0.05
    
                                Between and within city associations:
    
                                Bronchitis: 3.18 (between city)
    
                                Persistent phlegm (between city): 2.78
    
                                When scaled to an increment of
                                50 pg/m3 of PMi0.2 5 associations (ORs)
                                between respiratory outcome and PM10.
                                25 were:
    
                                Wheeze: 1.14
    
                                Asthma: 1.34
    
                                Bronchitis: 2.56
    
                                Hospitalization: 1.58
    
                                Persistent cough: 1.57
    
                                Persistent phlegm: 3.45
     All units expressed in pg/m  unless otherwise specified.
    December 2009
                              E-411
    

    -------
    Table E-24.    Long-term exposure - respiratory morbidity outcomes - PIVhs (including  PM
                      components/sources).
    Study
    Reference: Annesi-
    Maesanoetal.(2007,
    0913481
    
    Period of Study: Mar
    1999-0ct2000
    Location: France
    (Bordeaux, Clermont-
    Ferrand Creteil
    Marseille, Strasbourg,, &
    Reims)
    
    
    
    
    
    
    
    
    
    
    Design & Methods Concentrations1
    Outcome: EIB, Flexural atopic Pollutant: PM25
    dermatitis, asthma, rhiniconjuctivitis,
    allergic rhinitis Averaging Time: 5-day mean
    (Mon.-Fri.) over a 13-wkto 24-wk
    Age Groups: Children mean span
    10.4 + 0.7 yr
    Residential Proximity Level
    Study Design: Semi-individual
    design Mean (SD):
    Low cone: 8. 7
    N: 5338
    High cone: 20.7
    Statistical Analyses: Logistic
    regression Range (Min, Max):
    Covariates: Age, sex, family history Low conc: (1-6, 12.2)
    of allergy, passive smoking High cone: (12.5, 54.0)
    Season1 NR
    season. INK Qty Leve|
    Dose-response Investigated? No .. ,g-,.
    Statistical Package: SAS Low conc: 9 6
    High cone: 23.0
    Range (Min, Max):
    
    Low cone: (4.7, 12.7)
    
    High cone: (13.0, 54.5)
    Effect Estimates (95% Cl)
    PM Increment: High vs. Low
    Allergic and respiratory morbidity OR Estimate (Lower Cl,
    Upper Cl)
    Proximity Level
    EIB (0)1.35(1.10, 1.67)
    Fl. Atopic dermatitis (C) 2.51 (2.06, 3.06)
    Asthma (P) 1.11 (0.88, 1.39)
    Atopic asthma (P) 1.43 (1.07, 1.91)
    Non-atopic asthma (P) 0.73 (0.49, 1.07)
    Rhiniconjunctivitis (P) 0.94 (0.77, 1.15)
    Atopic dermatitis (P) 1.05(0.88, 1.27)
    Asthma (L) 1.00 (0.82, 1.22)
    Allergic Rhinitis (L) 1.09 (0.93, 1.27)
    Atopic dermatitis (L) 0.94 (0.82, 1.09)
    City Level
    EIB(C) 1.43(1.15, 1.78)
    Fl. Atopic dermatitis (C) 2.06 (1.69, 2.51)
    Asthma (P) 1.31 (1.04, 1.66)
    Atopic asthma (P) 1.58 (1.1 7, 2.14)
    Non-atopic asthma (P) 1.00 (0.68, 1.49)
    Rhiniconjunctivitis (P) 0.98 (0.80, 1.20)
    Atopic dermatitis (P) 1.08(0.90, 1.30)
    Asthma (L) 1.09 (0.89, 1.33)
    Allergic Rhinitis (L) 1.13 (0.97, 1.33)
    Atopic dermatitis (L) 0.95 (0.82, 1.09)
    Notes: C = Current
    P = Past yr
                                                                                         L = Lifetime
                                                                                         Allergic sensitization OR Estimate (Lower Cl, Upper Cl)
                                                                                         Proximity Level
                                                                                         All allergens 1.19 (1.04,1.36)
                                                                                         Indoor allergens 1.29 (1.11,1.50)
                                                                                         Outdoor allergens 1.02 (0.85,1.23)
                                                                                         Moulds 1.13 (0.78,  1.65)
                                                                                         City Level
                                                                                         All allergens 1.32 (1.15,1.51)
                                                                                         Indoor allergens 1.51 (1.29,1.76)
                                                                                         Outdoor allergens 1.06 (0.88,1.28)
                                                                                         Molds 1.00 (0.69, 1.46)      	
    Reference: Bakke et al.
    (2004, 1562461
    
    Period of Study: Jan
    1989-Jun2002
    
    Location: One of
    Norway's major
    construction companies
    Outcome: Spirometric
    measurements
    
    Age Groups: All ages, mean = 39
    yr
    
    Study Design: Cohort
    
    N: 651 male construction workers
    
    Statistical Analyses: Multiple
    linear regression models
    
    Covariates: Age, yr for non-
    smokers and ever smokers
    
    Dose-response Investigated? No
    
    Statistical Package: SYSTAT 10.0
    and SPSS 11.0
    Pollutant: Respirabledust
    
    Averaging Time: 5-8 h
    Mean (SD):
    Drill and blast workers: 6.3 (2.8)
    Tunnel concrete workers: 6.1 (3.1)
    Shotcreting operators: 19 (11)
    IBM workers: 16 (6.6)
    Outdoor concrete workers:  1.4
    (0.73)
    Foremen: 0.28 (0.48)
    Engineers:  0.09 (0.28)
    Unit (i.e. ug/m3): mg y/m3
    
    Monitoring Stations: 16 tunnel
    sites visited with sampling
    equipment
    Copollutant (correlation):
    Total dust: r = 0.99
    a quartz: r = 0.48
    N02:r = 0.75
    CO: r = 0.61
    Oil mist: r = 0.83
    Oil vapor: r = 0.68
    VOC:r = 0.89
    PM Increment: NR-exposure respirable dust
    
    Effect Estimate (Lower Cl, Upper Cl):
    
    Lung function changes predicted by multiple linear regression
    models using one exposure variable adjusted for age and
    observation time by non-smokers and ever smokers
    
    Non-smokers: IS = -16.0
    
    (-24- -6.8)
    
    SE = 4.5
    
    Ever smokers: IS = -9.3
    
    (-17--1.6)
    
    SE = 4.0
    December 2009
                                               E-412
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95% Cl)
    Reference: Bakke et al.
    (2004, 1562461
    
    Period of Study: Jan
    1989-Jun2002
    
    Location: One of
    Norway's major
    construction companies
    Outcome: Spirometric
    measurements
    
    Age Groups: All ages, mean = 39
    yr
    
    Study Design: Cohort
    
    N: 651 male construction workers
    
    Statistical Analyses: Multiple
    linear regression models
    
    Covariates: Age, yr for non-
    smokers and ever smokers
    
    Dose-response Investigated?
    
    No
    
    Statistical Package:
    
    SYSTAT 10.0 and SPSS 11.0
    Pollutant: Total dust
    
    Averaging Time: 5-8 h
    Mean (SD):
    Drill and blast workers: 18 (7.8)
    Tunnel concrete workers: 21 (11)
    Shotcreting operators: 73 (41)
    TBM workers: 48 (20)
    Outdoor concrete workers: 6.5 (3.4)
    Foremen: 0.78 (1.3)
    Engineers: 0.27 (0.78)
    
    Unit (i.e. ug/m3): mg y/m3
    
    Monitoring Stations: 16 tunnel
    sites visited with sampling
    equipment
    
    Copollutant (correlation):
    Respirable dust: r = 0.99
    a quartz: r = 0.42
    N02:r = 0.67
    CO: r = 0.49
    Oil mist: r = 0.81
    Oil vapor: r = 0.64
    VOC:r = 0.91
    PM Increment: NR-exposure expirable dust
    
    Lung function changes predicted by multiple linear regression
    models using one exposure variable adjusted for age and
    observation time by non-smokers and ever smokers
    
    Non-smokers: IS = -4.0 (-6.5-1.4)
    
    SE=1.3
    
    Ever smokers: IS = -2.0 (-4.2-0.23)
    
    SE=1.1
    Reference: Bennett et al. Outcome: Respiratory symptoms
    (2007, 1562681
    Period of Study:
    1992-2005
    
    Location: Melbourne,
    Australia
    (from questionnaire)
    
    Age Groups: All ages, mean = 37.2
    yr
    
    Study Design: Cohort
    
    N:1446
    
    Statistical Analyses: Logistic
    regression models
    
    Covariates: Age, gender, use of
    (S2-agonists, use of inhaled
    corticosteroids, smoking, yr of data
    collection, and avg daily exposure
    to PM25 in the 12 mo corresponding
    to the time frame of symptoms
    
    Dose-response Investigated? No
    
    Statistical Package: STATA,
    version 9
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD): 6.8
    
    Range (Min, Max): (1.8-73.3)
    
    Monitoring Stations: up to 3
    PM Increment: NR
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Respiratory symptoms in last 12 mo and exposure to ambient
    PM25 over the same period
    Within-person (longitudinal) effects
    Wheeze: OR = 1.08 (0.79-1.48), p = 0.62
    SOB on waking:  OR = 1.34 (0.84-2.16), p = 0.22
    Cough  (AM): OR = 0.74 (0.47-1.15), p = 0.18
    Phlegm (AM): OR =  1.55 (0.95-2.53), p = 0.08
    Cough  w/ phlegm (AM): OR = 1.28 (0.70-2.33), p = 0.42
    Asthma attack: OR = 0.91 (0.55-1.49), p = 0.69
    Between-person (cross-sectional) effects
    Wheeze: OR = 1.32  (0.82-2.10), p = 0.25
    SOB on waking:  OR = 1.29 (0.46-3.60), p = 0.63
    Cough  (AM): OR = 0.21 (0.07-0.62), p = 0.01
    Phlegm (AM): OR =  0.49 (0.16-1.44), p = 0.19
    Cough  w/ phlegm (AM): OR = 0.28 (0.08-0.97), p = 0.05
    Asthma attack: OR = 0.52 (0.17-1.59), p = 0.26
    December 2009
                                                E-413
    

    -------
            Study
          Design & Methods
           Concentrations1
                  Effect Estimates (95% Cl)
    Reference: (Brauer et
    al, 2007, 0906911
    
    Period of Study:
    1999-2000
    
    Location: The
    Netherlands
    Outcome:
    Allergen sensitivity (any, indoor,
    outdoor, food, total) lgE>100 lU/mL
    Asthma (probable, MD-diagnosed,
    ever MD-diagnosed)
    Bronchitis (MD-diagnosed, ever
    MD-diagnosed)
    Dry cough at night
    Itchy rash
    Itchy rash/eczema
    Ear/Nose/Throat (ENT) infection
    Eczema,  MD-diagnosed
    Eczema,  ever MD-diagnosed
    Flu/serious cold, MD-diagnosed
    Wheeze (ever, early, early frequent,
    persistent)
    Age Groups: Very young children
    (<4-yr-old) enrolled prenatally
    
    Study Design: Prospective birth
    cohort study
    
    N: -4000 subjects
    
    Statistical Analyses: Multiple
    logistic regression
    
    Dose-response Investigated? No
    Pollutant: PM25
    
    Averaging Time: 12 mo
    
    Mean (SD): SD: NR
    
    16.9
    
    Percentiles: 25th: 14.8
    
    SOth(Median): 17.3
    
    75th: 18.1
    
    Range (Min, Max): (13.5, 25.2)
    
    Monitoring Stations: 40
    
    Copollutant (correlation): Soot: r
    = 0.97
    
    N02:r = 0.93
    PM Increment: IQR 3.3 |ig/m
    
    Notes: Traffic-related pollution (PM25, soot, N02) was
    associated with respiratory infections, asthma, and allergic
    sensitization in children during the first 4 yr of life.
    Symptom At 4-Yr-Old
    Wheeze
    4-yr-old: 1.23 [1.00:1.51]
    Early-life: 1.20  [0.99:1.46]
    Asthma, MD-diagnosed
    4-yr-old: 1.15 [0.82:1.62]
    Early-life: 1.32  [0.96:1.83]
    Dry cough at night
    4-yr-old: 1.11 [0.94:1.31]
    Early-life: 1.14  [0.98:1.33]
    Bronchitis, MD-diagnosed
    4-yr-old: 0.88 [0.66:1.18]
    Early-life: 0.86  [0.66:1.11]
    ENT infection
    4-yr-old: 1.13 [0.98:1.31]
    Early-life: 1.17  [1.02:1.34]
    Flu/serious cold, MD-diagnosed
    4-yr-old: 1.21 [1.02:1.42]
    Early-life: 1.25  [1.07:1.46]
    Itchy rash
    4-yr-old: 0.96 [0.82:1.11]
    Early-life: 0.98  [0.85:1.14]
    Eczema,  MD-diagnosed
    4-yr-old: 1.00 [0.88:1.21]
    Early-life: 0.98  [0.82:1.17]
    Allergen Sensitivity At 4-Yr-Old
    Allergen,  any: 1.55 [1.13: 2.11]
    Allergen,  indoor: 1.03 [0.69:1.55]
    Allergen,  outdoor: 0.93 [0.54:1.58]
    Allergen,  food:  1.75 [1.23: 2.47]
    Allergen,  total lgE>100 lU/mL: 0.84 [0.59:1.18]
    Cumulative Allergy/Asthma Symptoms At 4-Yr-Old
    Wheeze,  ever:  1.22 [1.06:1.41]
    Asthma, ever MD-diagnosed: 1.32 [1.04:1.69]
    Asthma, probable: 1.08 [0.90:1.30]
    Wheeze,  early: 1.16 [1.00:1.34]
    Wheeze,  persistent:  1.19 [0.96:1.48]
    Wheeze,  early  frequent: 1.19 [0.96:1.47]
    Bronchitis, ever MD-diagnosed: 0.96 [0.81:1.13]
    Itchy rash/eczema: 0.99 [0.88:1.13]
    Eczema,  ever MD-diagnosed: 0.98 [0.85:1.13]	
    December 2009
                                                  E-414
    

    -------
            Study
          Design & Methods
           Concentrations1
                  Effect Estimates (95% Cl)
    Reference: (Brauer et
    al, 2007, 0906911
    Period of Study:
    1999-2000
    Location: The
    Netherlands
    Outcome: Allergen sensitivity (any, Pollutant: Soot (as PM25
    indoor, outdoor, food, total) lgE>100 absorbance)
    lu/mL . • ,- „,
    Averaging Time: 12 mo
    Asthma (probable, MD-diagnosed,
    ever MD-diagnosed) Mean (SD): 171
    Bronchitis (MD-diagnosed, ever Percentiles:
    MD-diagnosed) 25th: 1.33
    PM Increment: IQR 0.58 E-5/m
    Notes: Traffic-related pollution (PM25, soot, N02) was
    associated with respiratory infections, asthma, and allergic
    sensitization in children during the first 4 yr of life.
    Symptom At 4-Yr-Old
    Wheeze
    4-yr-old: 1.18 [0.98: 1.41]
    Earlv-life: 1.18 M.00:1. 401
                            Dry cough at night
    
                            Itchy rash
    
                            Itchy rash/eczema
    
                            Ear/Nose/Throat (ENT) infection
    
                            Eczema, MD-diagnosed
    
                            Eczema, ever MD-diagnosed
    
                            Flu/serious cold, MD-diagnosed
    
                            Wheeze (ever, early, early frequent,
                            persistent)
    
                            Age Groups: Very young children
                            (<4-yr-old) enrolled prenatally
    
                            Study Design:  Prospective birth
                            cohort study
    
                            N: -4000 subjects
    
                            Statistical Analyses: Multiple
                            logistic regression
    
                            Dose-response Investigated? No
                                      SOth(Median): 1.78
    
                                      75th: 1.91
    
                                      Range (Min, Max): (0.77, 3.68)
    
                                      Unit (i.e. ug/m3): 1 E-5/m
    
                                      Monitoring Stations: 40
    
                                      Copollutant (correlation):
    
                                      N02:r = 0.96
    
                                      PM25:r = 0.97
                                     Asthma, MD-diagnosed
                                     4-yr-old: 1.15 [0.85:1.55]
                                     Early-life: 1.30 [0.98:1.71]
                                     Dry cough at night
                                     4-yr-old: 1.13 [0.97:1.30]
                                     Early-life: 1.14 [1.00:1.31]
                                     Bronchitis, MD-diagnosed
                                     4-yr-old: 0.90 [0.69:1.16]
                                     Early-life: 0.88 [0.69:1.11]
                                     ENT infection
                                     4-yr-old: 1.15 [1.01:1.31]
                                     Early-life: 1.16 [1.03:1.31]
                                     Flu/serious cold, MD-diagnosed
                                     4-yr-old: 1.18 [1.02:1.36]
                                     Early-life: 1.19 [1.04:1.37]
                                     Itchy rash
                                     4-yr-old: 0.94 [0.82:1.08]
                                     Early-life: 0.97 [0.85:1.10]
                                     Eczema, MD-diagnosed
                                     4-yr-old: 0.99 [0.84:1.17]
                                     Early-life: 0.97 [0.83:1.14]
                                     Allergen Sensitivity At 4-Yr-Old
                                     Allergen, any: 1.45 [1.11:1.91]
                                     Allergen, indoor: 1.02 [0.71:1.46]
                                     Allergen, outdoor: 0.95 [0.59:1.52]
                                     Allergen, food: 1.64 [1.21: 2.23]
                                     Allergen, total lgE>100 lU/mL: 0.80 [0.59:1.09]
                                     Cumulative Allergy/Asthma Symptoms At 4-Yr-Old
                                     Wheeze, ever: 1.18 [1.04:1.34]
                                     Asthma, ever MD-diagnosed: 1.26 [1.02:1.56]
                                     Asthma, probable: 1.06 [0.90:1.24]
                                     Wheeze, early:  1.11 [0.97:1.26]
                                     Wheeze, persistent: 1.18 [0.98:1.42]
                                     Wheeze, early frequent: 1.14 [0.95:1.37]
                                     Bronchitis, ever MD-diagnosed: 0.95 [0.82:1.10]
                                     Itchy rash/eczema: 0.99 [0.89:1.11]
                                     Eczema, ever MD-diagnosed:  0.99 [0.87:1.12]
    Reference: Brauer et al.
    (2002, 0351921
    
    Period of Study: NR
    
    Location: The
    Netherlands
    Outcome: Questionnaire derived     Pollutant: PM25
    wheezing, dry nighttime cough, ear,
    nose and throat infections, skin rash  Averaging Time: 4 2-wk periods
                                      dispersed throughout 1 yr, adjusted
    Physician diagnosed asthma,
    bronchitis, influenza, eczema
                            Age Groups: age 2
    
                            Study Design: Prospective cohort
    
                            N: 4146 children
    
                            Statistical Analyses: Logistic
                            regression
    for temporal trend
    
    Mean (SD): 16.9
    
    Percentiles:
    10th: 14.0
    
    25th: 15.0
    
    SOth(Median): 17.3
    
    75th: 18.2
                            Covariates: Maternal age, maternal
                            smoking, mattress cover (allergen-   90tn: la1
                            free), maternal education,  paternal
                            education, gender, gas stove, gas
                            water heater, any other siblings,
                            ethnicity, breastfeeding, mold at
                            home, pets, allergies in mother,
                            allergies in father
                                      Range (Min, Max): 13.5, 25.2
    
                                      Monitoring Stations: 40
                            Dose-response Investigated? No
                                      Copollutant (correlation):
                                      Soot: r = 0.99
                                      N02:r = 0.97
    PM Increment: 3.2 pg/m
    
    OR Estimate [Lower Cl, Upper Cl];
    Unadjusted
    Wheeze 1.14 (0.99-1.30)
    Asthma 1.08 (0.84-1.37)
    Dry cough at night 1.10 (0.95-1.27)
    Bronchitis 1.00 (0.85-1.18)
    E, N, T infections 1.14 (0.99-1.33)
    Flu 1.15 (1.03-1.28)
    Itchy rash 1.07 (0.95-1.20)
    Eczema 1.02  (0.90-1.16)
    Adjusted
    Wheeze 1.14 (0.98-1.34)
    Asthma 1.12 (0.84-1.50)
    Dry cough at night 1.04 (0.88-1.23)
    Bronchitis 1.04 (0.85-1.26)
    E, N, T infections 1.20 (1.01-1.42)
    Flu 1.12 (1.00-1.27)
    Itchy rash 1.01 (0.88-1.16)
    Eczema 0.95  (0.83-1.10)
    December 2009
                                                  E-415
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95% Cl)
    Reference: Brauer et al.
    (2002, 0351921
    
    Period of Study: NR
    
    Location: The
    Netherlands
    Outcome: Questionnaire derived
    wheezing, dry nighttime cough, ear,
    nose and throat infections, skin rash
    
    Physician diagnosed asthma,
    bronchitis, influenza, eczema
    
    Age Groups: Age 2
    
    Study Design: Prospective cohort
    
    N: 4146 children
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Maternal age, maternal
    smoking, mattress cover (allergen-
    free), maternal education, paternal
    education, gender, gas stove, gas
    water heater, any other siblings,
    ethnicity, breastfeeding, mold at
    home, pets, allergies in mother,
    allergies in father
    
    Dose-response Investigated? No
    Pollutant: PM25 "soot"
    
    Averaging Time: 4 2-wk periods
    dispersed throughout 1 yr, adjusted
    for temporal trend
    Mean (SD): 16.9 10-5/m
    Percentiles: 10th: 1.16
    25th: 1.38
    SOth(Median): 1.78
    75th: 1.92
    90th: 2.19
    Range (Min, Max):  0.77, 3.68
    
    Unit (i.e. ug/m3): 10-5/m
    
    Monitoring Stations: 40
    
    Copollutant (correlation):
    PM25(r = 0.99)
    N02(r = 0.96)
    PM Increment: 0.54 x 10-5/m (equivalent to 0.8 pg/m EC)
    
    OR Estimate [Lower Cl, Upper Cl]
    Unadjusted
    Wheeze 1.11 [0.99-1.24]
    Asthma 1.07 [0.87-1.31]
    Dry cough at night 1.08 [0.95-1.21]
    Bronchitis 0.98 [0.85-1.12]
    E,N,T infections 1.12 [0.99-1.27]
    Flu 1.13 [1.03-1.23]
    Itchy rash 1.07 [0.97-1.19]
    Eczema 1.01 [0.91-1.13]
    Adjusted
    Wheeze 1.11 [0.97-1.26]
    Asthma 1.12 [0.88-1.43]
    Dry cough at night 1.02 [0.88-1.17]
    Bronchitis 0.99 [0.84-1.17]
    E,N,T infections 1.15 [1.00-1.33]
    Flu 1.09 [0.98-1.21]
    Itchy rash 1.02 [0.91-1.15]
    Eczema 0.96 [0.85-1.08]
    Reference: Brauer et al.
    (2006, 0907571
    Period of Study:
    1997-2001
    
    Location: Germany
    The Netherlands
    
    
    
    
    
    
    
    
    
    Reference: Burr etal.
    (2004, 0878091
    Period of Study: 3 wk in
    Jul and Jan 1997 and 2
    wkinNov1996andApr
    1997
    Location: North Wales,
    England
    
    
    
    
    
    Outcome: Otitis Media (parental
    report of doctor's diagnosis prior to
    age 2 yr)
    Age Groups: 0-2 yr
    
    Study Design: Prospective Cohort
    Study
    N: 4,379 children total
    The Netherlands: 3,714
    Germany: 665
    Statistical Analyses: Logistic
    regression
    Covariates: Sex, parental atopy,
    maternal education, siblings,
    maternal smoking during
    pregnancy, ETS exposure at home,
    use of gas for cooking, indoor
    moulds and dampness, number of
    siblings, breast-feeding, and
    presence of pets in the home
    Season: All
    Dose-response Investigated? No
    Outcome: Self-report of symptoms
    only for wheeze, cough, phlegm,
    rhinitis, and itchy eyes.
    
    Age Groups: All
    Study Design: Repeated measures
    N: 386 persons in congested
    streets and 425 in the uncongested
    streets in 1996/1997. Of these, 165
    and 283 completed the second
    phase of the study.
    
    
    Pollutant: PM25
    PM Component: EC (EC)
    Averaging Time: 8 wk (4 2-week
    periods dispersed throughout 1 yr,
    adjusted for temporal trends)
    Mean:
    The Netherlands:
    P M • 1 R Q
    r IVI2 5. I u.y
    EC: 1.72
    fnprm3ny
    oci 1 1 ioi ly.
    PM25:13.4
    EC: 1.76
    Range (Min, Max):
    The Netherlands:
    PM25: 13.5, 25.2
    EC: 0.77, 3.68
    Germany:
    PM25: 12.0, 21.9
    EC: 1.40, 4.39
    Monitoring Stations: 80 (40 for
    each cohort)
    
    
    Pollutant: PM25
    Averaging Time: Mean hourly
    concentrations
    Mean (SD):
    Congested Streets
    1996-9721.2
    1998-9916.2
    Uncongested Streets
    1996-976.7
    1998-994.9
    Monitoring Stations: 1 in
    congested street and 1 in
    uncongested
    PM Increment: PM25: 3 pg/m3 (~ IQR)
    EC: -0.5 pg/m3 (~ IQR)
    OR Estimate [Lower Cl, Upper Cl]
    
    The Netherlands:
    PM25:
    At agel: 1.13(0.98-1.32
    At age 2: 1.13 (1.00-1.27
    EC'
    At age 1:1. 11 (0.98-1.26)
    At age 2: 1.10 (1.00-1.22)
    Germany:
    DM
    PM25.
    At agel: 1.19(0.73-1.92)
    At age 2: 1.24 (0.84-1. 83)
    EC1
    At age 1:1. 12 (0.83-1.51)
    At age 2: 1.10 (0.86-1.41)
    
    
    
    % change PM10 in congested streets: 23.6
    % change PMi0 in uncongested streets: 26.6
    
    Uncongested street sampling site was 20 m from the
    congested street sampler.
    The opening of the by-pass produced a reduction in pollution
    in the congested streets. The health effects of these changed
    are likely to be greater for nasal and ocular symptoms than for
    lower respiratory symptoms. Uncertainty about the causality
    arises from low response rates and conflicting trends in
    respiratory and nasal symptoms.
    
    
    December 2009
                                                 E-416
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95%  Cl)
    Reference: Calderon-
    Garciduefias et al. (2006,
    0912531
    
    Period of Study:
    1999-2000
    
    Location: Southwest
    Mexico City & Tlaxcala,
    Mexico
    Outcome: Hyperinflation, interstitial
    markings-measured by chest
    radiograph, and lung function-FVC,
    FEV,, PEF, FEF25-75, measured
    using spirometry tests
    
    Age Groups: 5-13 yr
    
    Study Design: Cohort1999-
    
    N: 249 (total), 230 (Southwest
    Mexico City), 19 (Tlaxcala)
    
    Statistical Analyses: Bayestest,
    Spearman rank correlation,  multiple
    regression
    
    Covariates: Age, sex
    
    Dose-response Investigated? No
    
    Statistical Package: SAS 8.2
    Pollutant: PM25
    
    Averaging Time: 1 yr
    
    Mean (SD): 21
    
    2000-19
    
    Tlaxacala:
    
    1994-2000: 
    -------
    Study
    Reference: Dales etal.,
    (2008, 1563781
    Period of Study:
    Location: Windsor, ON
    
    
    
    
    
    
    
    
    Reference: Gauderman
    et al. (2000, 0125311
    
    Period of Study:
    1993-1997
    Location: Southern
    California
    
    
    
    
    
    
    Reference: Gauderman
    et al. (2002, 0260131
    Period of Study:
    1996-2000
    Location: Southern
    California
    
    Design & Methods
    Outcome: Pulmonary function and
    inflammation
    Age Groups: Grades 4-6
    Study Design: Cross-sectional
    prevalence design
    
    Statistical Analyses: Multivariate
    linear regression
    Covariates: Ethnic background,
    smokers at home, pets at home,
    acute respiratory illness, medication
    use
    Outcome: FVC, FEV,, MMEF,
    FEF75
    
    Age Groups: Fourth, seventh, or
    tenth graders
    Study Design: Cohort
    N: 3035 subjects
    
    Statistical Analyses: Linear
    regression
    Covariates: Height, weight, BMI,
    asthma, smoking, exercise, room
    temperature, barometric pressure
    Dose-response Investigated? Yes
    Statistical Package: SAS
    Outcome: Lung function
    development: FEV,, maximal
    midexpiratory flow (MMEF)
    
    Age Groups: Fourth grade children
    (avg age = 9.9yr)
    
    Study Design: Cohort study
    N: 1678 children, 12 communities
    Concentrations1
    Pollutant: PM25
    Averaging Time: Annual
    Mean: 15.4
    5th: 14.2
    
    95th: 17.2
    Copollutant:
    en
    0^2
    N02
    
    Pollutant: PM25
    
    Averaging Time: Annual avg of
    2-wkavgPM25
    Mean (SD):PM25 25.9
    Copollutant (correlation):
    03: r = -0.32
    DUrt • i- — n 7C
    rM,o-2.5. r- U. 10
    N02:r = 0.74
    Inorg.Acid: r = 0.79
    
    
    Pollutant: PM25
    Averaging Time: Annual 24-h avg
    
    Mean (SD): The avg levels were
    presented in an online data
    supplement (Fig E1)
    PM Component: EC and OC.
    
    Effect Estimates (95% Cl)
    Increment: Tertiles of exposure
    FEV,:
    <15.19: 2.16 + 0.01
    15.19-15.96:2.17 + 0.02
    >15.96: 2.18 + 0.01
    FVC:
    <15.19: 2.51 +0.02
    15.19-15.96:2.50 + 0.02
    >15.96: 2.52 + 0.02
    eNO:
    <15.19: 16.08 + 0.70
    15.19-15.96: 15.80 + 0.76
    >15.96: 16.79 + 0.72
    
    Increment: 25.9 pg/m3
    
    % Change (Lower Cl, Upper Cl)
    PM25-4th grade
    FVC -0.47 (-0.94, 0.01)
    FEV, -0.64 (-1.28, 0.01)
    MMEF -1.03 (-1.95 to -0.09)
    FEF75-1.31 (-2.57 to -0.03)
    PM25-7th grade
    FVC -0.42 (-0.89, 0.05)
    FEV, -0.32 (-0.88, 0.24)
    MMEF -0.29 (-1.99, 1.44)
    FEF75 -0.26 (-1.75, 1.25)
    PM25-10th grade
    FVC 0.19 (-0.68, 1.07)
    FEV, -0.25 (-1.41, 0.93)
    MMEF -0.17 (-3.66, 3.46)
    FEF75 -0.79 (-4.27, 2.82)
    PM Increment: 22.2 pg/m3
    Association Estimate:
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Non-statistically significant negative correlation between PM2 5
    and FEV,and FVC growth rates were observed. MMEF growth
    rates had a negative correlation with PM25 (r = -0.43 p =
    PM2 5 was not significantly correlated to FEV, (r = -0.31
    p = 0.25)
    
    0.05).
    
    
                           Statistical Analyses: Mixed model
                           linear regression
    
                           Covariates: Height, BMI, doctor-
                           diagnosed asthma and cigarette
                           smoking in previous yr, respiratory
                           illness and exercise on day of test,
                           interaction of each of these
                           variables with sex, barometric
                           pressure, temperature at test time,
                           indicator variables for field
                           technician and spirometer
    
                           Dose-response Investigated? Yes
    
                           Statistical Package: SAS (10)
    Monitoring Stations: 12
    
    Copollutant (correlation):
    
    03:(10AMto6PM)r = 0.14
    
    03:r = -0.39
    
    N02:r = 0.77
    
    Acid vapor: r = 0.87
    
    PM,0:r = 0.95
    
    PM,0.25:r = 0.81
    
    EC: r = 0.93
    
    OC:r = 0.89
    December 2009
                E-418
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95% Cl)
    Reference: (Gauderman
    etal., 2004, 0565691
    
    Period of Study: Air
    pollution data
    ascertainment:
    1994-2000. Spirometry
    testing: spring
    2001-spring 2003
    
    Location:  12
    Communities in Southern
    California
    Outcome: Lung function
    FVC, FEV,, MMEF (Maximal
    midexpiratory flow rate)
    
    Age Groups: Children, Avg age 10
    yr
    
    Study Design: Prospective Cohort
    Study
    
    N: 12 Communities
    2,034 children
    24,972 child-mo
    
    Statistical Analyses: Linear
    regression of changes in sex-and-
    community specific lung growth
    function and PM
    
    Correlation between % with low
    attained FEV, and PM.
    
    Covariates: Random effect for
    communities
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    Pollutant: PM25
    
    Averaging Time: 2-wk
    measurements used to create
    annual avg
    
    Mean: Means are presented in
    figures only.
    
    Range (Min, Max): ~6, -27
    
    Monitoring Stations:  12
    
    Copollutant (correlation):
    PM10:r = 0.95
    
    03:r = 0.18
    
    N02:r = 0.79
    
    EC: r = 0.91
    
    OC:r = 0.91
    PM Increment: Most to least polluted community Range:
    
    22.8 pg/m3
    
    Difference in Lung Growth [Lower Cl, Upper Cl];
    
    FVC-60.1 (-166.1 to 45.9)
    
    FEV, -79.7 (-153.0 to j6.4)
    
    MMEF-168.9 (-345.5 to 7.8)
    
    Correlation with % below 80% predicted Lung function (p-
    value)
    
    PM25: 0.79 (0.002)
    Reference: Gauderman
    et al. (2007, 0901211
    
    Period of Study:
    1993-2004
    
    Location: 12 Southern
    California Communities
    Outcome: Pulmonary function tests  Pollutant: PM
    FVC, FEV,, MMEF/FEF25.75
    Age Groups: Children (mean age
    10 at recruitment, followed for 8 yr)
    
    Study Design: Cohort Study
    (Children's Health Study)
    
    N: 3677 children (1718 in cohort 1
    recruited 1993 and 1959 in cohort 2
    recruited 1996)
    
    22686 pulmonary function tests.
    
    Statistical Analyses: Hierarchical
    mixed effects model with linear
    splines
    
    Covariates: Adjustments for height,
    height squared, BMI, BMI squared,
    present asthma status, exercise or
    respiratory illness on day of test,
    smoking in previous yr, field
    technician, traffic indicator (distance
    from freeway, distance from major
    roads), random effects for
    participant and community.
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    Monitoring Stations: 1 in each
    community
    PM Increment: 22.8 pg/m
    
    Pollutant effect reported as difference in 8 yr lung function
    growth from least to most polluted community. Negative
    difference indicate growth deficits associated with exposure.
    For PM2 5 FEV growth deficit is -100
    Reference: Gehring et
    al. (2002, 0362501
    
    Period of Study:
    1995-2002
    
    Location: Munich,
    Germany
    Outcome: Wheezing, cough
    without infection, dry cough at night,
    obstructive, spastic or asthmoid
    bronchitis, respiratory infections,
    sneezing, runny/stuffed nose
    
    Age Groups: 0-2 yr
    
    Study Design: Prospective cohort
    
    N: 1756 infants
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Sex, parental atopy
    (yes/no), maternal education,
    siblings  (y/n), environmental
    tobacco smoke at home (y/n), use
    of gas for cooking (y/n), home
    dampness (y/n), indoor moulds
    Pollutant: PM25
    
    Mean (SD):PM25 mass: 13.4
    
    PM25 absorb. 1.77*10-5/m
    
    Percentiles: PM25 mass:
    
    10th: 12.2
    
    25th: 12.5
    
    50th(Median):13.1
    
    75th: 14.0
    
    90th: 14.9
    
    PM25 absorbance:
    
    10th: 1.47* 10-5
    
    25th: 1.54* 10-5
    PM Increment:
    PM25 mass: 1.5 pg/m
    PM25 absorb. 0.4* 10-5/m(IQR)
    
    RR Estimate [Lower Cl, Upper Cl]
    Wheeze (PMu mass)
    Age of 1 yr: All: 0.91 (0.76-1.09)
    Males: 0.91 (0.72-1.16)
    Females: 0.94 (0.70-1.27)
    Age of 2 yr: All: 0.96 (0.83-1.12)
    Males: 0.93 (0.76-1.14)
    Females: 1.04 (0.83-1.30)
    Cough W/0 Infection (PM25 mass)
    Age of 1 yr: All: 1.34 (1.11-1.61)
    Males: 1.43 (1.14-1.80)
    Females: 1.19 (0.84-1.70)
    Dry Cough At Night (PM25 mass)
    Age of 1yr: All: 1.31 (1.07-1.60)
    Males: 1.39 (1.08-1.78)
    Females: 1.17 (0.81-1.68)
    December 2009
                                                 E-419
    

    -------
            Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                           (y/n), keeping of dogs (y/n) and cats
                           (y/n) study (GINI or LISA)
    
                           Dose-response Investigated? No
                               SOth(Median): 1.70* 10-5
    
                               75th: 1.88* 10-5
    
                               90th: 2.13* 10-5
    
                               Range (Min, Max):
    
                               PM2.5 mass: 11.9, 21.9
    
                               PM25 absorbance:
    
                               1.38to4.39*10-5
    
                               PM25 mass:
    
                               PM25 absorbance: 1/m
    
                               PM Component: PM25 mass
    
                               PM2 5 absorbance (as a marker of
                               diesel soot)
    
                               Monitoring Stations: 40
    
                               Copollutant (correlation):
    
                               N02:r = 0.99
    
                               PM25 absorbance and N02: r = 0.95
    
                               PM25 mass and PM25 absorbance:
                               r = 0.96
                              Age of 2 yr: All: 1.20 (1.02-1.42)
                              Males: 1.25 (1.01-1.55)
                              Females: 1.13 (0.86-1.48)
                              Bronchitis (PM25 mass)
                              Age of 1 yr: All: 0.98 (0.80-1.20)
                              Males: 0.97 (0.76-1.25)
                              Females: 0.98 (0.68-1.41)
                              Age of 2 yr: All: 0.92 (0.78-1.09)
                              Males: 0.92 (0.74-1.14)
                              Females: 0.91 (0.68-1.21)
                              Resp Infections (PM25 mass)
                              Age of 1yr: All: 1.04 (0.91-1.19)
                              Males: 1.04 (0.87-1.25)
                              Females: 1.06 (0.87-1.31)
                              Age of 2 yr: All: 0.98 (0.80-1.20)
                              Males: 0.99 (0.74-1.31): Females: 0.98 (0.73-1.31)
                              Sneezing/Runny Nose (PM25 mass)
                              Age of 1yr: All: 1.01 (0.85-1.20)
                              Males: 0.97 (0.77-1.24)
                              Females: 1.08 (0.84-1.41)
                              Age of 2 yr: All: 0.96 (0.82-1.12)
                              Males: 0.91 (0.73-1.12)
                              Females: 1.04 (0.83-1.31)
                              Wheeze (PM25 absorbance)
                              AgeoH yr: All: 0.93(0.78-1.12)
                              Males: 0.91 (0.71-1.15)
                              Females: 1.01 (0.74-1.37)
                              Age of 2 yr: All: 0.98 (0.84-1.14)
                              Males: 0.92 (0.75-1.13)
                              Females: 1.07 (0.85-1.36)
                              Cough W/0 Infection (PM25  absorbance)
                              AgeoH yr: All: 1.32 (1.10-1.59)
                              Males: 1.38 (1.11-1.71)
                              Females: 1.25 (0.87-1.78)
                              Dry Cough At Night (PM25 absorbance)
                              Age oHyr: All: 1.27 (1.04-1.55)
                              Males: 1.31 (1.04-1.67)
                              Females: 1.16 (0.79-1.71)
                              Age of 2 yr: All: 1.16 (0.98-1.37)
                              Males: 1.17 (0.95-1.44)
                              Females: 1.12 (0.84-1.48)
                              Bronchitis (PM25 absorbance)
                              Age of 1 yr: All: 0.99 (0.81-1.22)
                              Males: 1.00 (0.78-1.27)
                              Females: 0.94 (0.63-1.39)
                              Age of 2 yr: All: 0.94 (0.79-1.12)
                              Males: 0.91 (0.72-1.13)
                              Females: 0.95 (0.71-1.28)
                              Resp Infections (PM25 absorbance)
                              Age of 1 yr: All: 1.03 (0.90-1.18)
                              Males: 1.03 (0.86-1.23)
                              Females: 1.05 (0.85-1.30)
                              Age of 2 yr: All: 0.99 (0.80-1.22)
                              Males: 0.96 (0.73-1.26)
                              Females: 1.04 (0.75-1.43)
                              Sneezing/Runny Nose (PM25 absorbance)
                              Age oHyr: All: 0.95 (0.79-1.14)
                              Males: 0.90 (0.70-1.16)
                              Females: 1.06 (0.80-1.39)
                              Age of 2 yr: All: 0.92 (0.78-1.09)
                              Males: 0.83 (0.66-1.05)
                              Females: 1.06 (0.83-1.34))	
    December 2009
                                           E-420
    

    -------
    Study
    Reference: Goss et al.
    (2004, 0556241
    Period of Study:
    1999-2000
    
    Location: USA
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: Hertz-
    Picciotto et al. (2005,
    0886781
    Period of Study: May
    1994-Mar1999
    Location: Teplice and
    Prachatice, Czech
    Republic
    
    
    
    
    
    
    Design & Methods
    Outcome: Cystic Fibrosis
    pulmonary exacerbations, FEVi
    Age Groups: Children and adults
    over the age of 6
    
    Study Design: Ccohort
    
    N: 11484 patients
    
    Statistical Analyses: Logistic
    regression, t-tests, Mann-Whitney
    tests, Chi-squared tests,
    polytomous regression, multiple
    linear regression
    Covariates: Age, sex, lung
    function, weight, insurance status,
    pancreatic insufficiency, airway
    colonization, genotype, median
    household income by census tract,
    zipcode.
    Dose-response Investigated? No
    Statistical Package: STATA, SAS
    Outcome: Developmental
    immunotoxicity as assessed by
    neonatal immunophenotypes
    Age Groups: Not specified: every
    woman who delivered in the two
    aforementioned districts were asked
    to participate
    Study Design: Cohort study
    N: 1397 mother-infant pairs
    Statistical Analyses: Multiple
    linear regression with lymphocyte
    percentage as responding variable
    and pollutant exposure to 14day
    averaging period before the date of
    cord blood collection
    Concentrations1
    Pollutant: PM25
    Averaging Time: Annual mean of
    24-h avg
    Mean (SD): 13.7(4.2)
    
    Percentiles:25th:11.8
    
    SOth(Median): 13.9
    
    75th: 15.9
    Monitoring Stations: 713
    
    
    
    
    
    
    
    Pollutant: PM25
    Averaging Time: 24 h
    14 day avg
    Mean (SD): Overall 24 h: 24.8
    14-day avg:
    Teplice: 30.1
    Prachatice 19.8
    PM Component: PAHs
    Monitoring Stations: 2 stations:
    Teplice and Prachatice
    
    
    Effect Estimates (95% Cl)
    PM Increment: 10 pg/m3
    Odds Ratio Estimate [Lower Cl, Upper Cl]:
    Odds of having 2 or more pulmonary exacerbations as
    compared to 1 or less in 2000
    
    1.21 (1.07-1.33)
    
    Odds of having 1 pulmonary exacerbation as compared to no
    exacerbations in 2000
    
    0.70 (0.59-0.98)
    Decrease in FEV, 155ml(115-194)
    Decrease in FEV, in 2000 after adjusting for FEV, in 1999
    24ml(7-40)
    
    
    
    
    
    
    PM Increment: 25 pg/m3
    Adjusted for 3-day temperature and season, PM2 5 exposure
    during the 14 days before birth was associated with reduced
    T-lymphocyte fractions CD4+, CD3+ and an increase in B-
    lymphocyte fraction (CD19+).
    The associations were not quantitatively reported anywhere
    else in the paper other than in Fig 2 and Table 3
    
    
    
    
    
    
    
                            Covariates: Season, length of
                            labor, parity, number of previous
                            stillbirths, medication during
                            delivery, working status of mother,
                            maternal education, exposure to
                            active and secondhand smoke,
                            family history of allergy, self-reports
                            of workplace exposure to dust
                            during pregnancy, self-reported
                            maternal chronic or severe
                            respiratory diseases during
                            pregnancy. Ambient temperature
                            and season were controlled for.
    
                            Dose-response Investigated? Yes
    
                            Statistical Package: SUDAAN
                            (version 8)
    December 2009
    E-421
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95% Cl)
    Reference: (Hertz-
    Picciotto et al, 2007,
    1359171
    
    Period of Study:
    1994-98 +follow-ups at
    up to 4.5 yr of age for
    child
    
    Location:  Czech
    Republic districts of
    Teplice and Prachatice
    Outcome: Lower respiratory
    illnesses, majority being acute
    laryngitis, tracheitis, bronchitis.
    
    ICD10 codes J04 and J20
    
    Age Groups: Birth-4.5  yr of age.
    
    Study Design: Longitudinal follow
    up of a stratified random sample of
    mother-infant pairs from previous
    Pregnancy Outcome Study. Low
    birth weight and preterm births
    sampled at higher fractions.
    
    N: 1133 children
    
    Statistical Analyses: Generalized
    linear longitudinal models, GEE to
    adjust for within subject
    correlations, robust variance
    estimates were obtained.  Model fit
    judged using Akaike Information
    criterion.
    
    Covariates: Age of child, breast
    feeding, environmental  tobacco
    smoke, season, day of  week, yrof
    birth, gender, birth weight,
    pregnancy data including age at
    delivery, length of gestation,
    maternal hypertension and
    diabetes, infant APGAR score,
    maternal work history,
    demographics, lifestyle,
    reproductive and medical histories,
    temperature, fuel type,  other
    children in household
    
    Dose-response Investigated? No
    
    Statistical Package: SUDAAN
    version 8
    Pollutant: PM25
    
    Averaging Time: Used 3-, 7-, 14-,
    30- and 45-day avg
    
    Mean (SD): Daily mean 22.3
    
    (sd 16 for 3-day avg, 11 for 45-day
    avg)
    PM Increment: 25 pg/m
    
    RR Estimate [Lower Cl, Upper Cl] lag:
    Bronchitis, birth-23 mo of age
    Categorical model
    High 30-day avg PM2 5 (greater than 50 pg/m3)
    2.26(1.81-2.82)
    Medium 30-day avg PM25 (between 25 and 50 pg/m3)
    1.48(1.32-1.65)
    Continuous model
    1.30(1.08-1.58)
    Bronchitis, 2-4.5 yrof age
    Categorical model
    High 30-day avg PM25 (greater than 50 pg/m3)
    3.66(2.07-6.48)
    Medium 30-day avg PM25 (between 25 and 50 pg/m3)
    1.60(1.41-1.82)
    Continuous model
    1.23(0.94-1.62)
    
    Notes: Results of other averaging periods shown in plots.
    Reference: (Hogervorst
    et al, 2006, 156559)
    
    Period of Study: NR
    
    Location: Maastricht, the
    Netherlands (six schools
    selected)
    Outcome:
    
    Decreased lung function
    
    Age Groups: 8-1 Syr old
    
    Study Design: Multivariate linear
    regression (enter method) analysis
    
    N: 342 children
    
    Statistical Analyses: ANOVA, Chi
    square
    
    Covariates:  Independent variables:
    Age, height, gender, smoking at
    home by parents, pets,  use of
    ventilation hoods during cooking,
    presence of unvented geysers,
    tapestry in the home, indoor/outdoor
    time, education level of parents.
    
    Dependent variables: lung function
    indices
    
    Dose-response Investigated? No
    Pollutant: PM25
    
    Averaging Time: Daily
    
    Mean (SD): 19.0 (3.2)
    
    Monitoring Stations: 6
    
    Copollutant:
    
    PM10
    
    TSP
    PM Increment: 10|jg/m
    
    RR Estimate [Lower Cl, Upper Cl] lag:
    
    FEV
    
    3.62 [0.50,7.63]
    
    FVC
    
    1.80 [-2.10, 5.80]
    
    FEF
    
    5.93 [-2.34, 14.89]
    December 2009
                                                 E-422
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95% Cl)
    Reference: Islam et al.
    (2007, 0906971
    
    Period of Study:
    1993-2001
    
    Location: 12
    communities in Southern
    California, U.S.
    Outcome: New onset asthma
    
    Age Groups: 9-1 Oyr
    
    Study Design: Cohort
    
    N:2057
    
    Statistical Analyses: Cox
    proportional hazard model
    
    Covariates: Community, sex,
    race/ethnicity
    
    Season: All
    
    Dose-response Investigated? No
    
    Statistical Package: SASV 9.1
    
    Lags Considered: 0-2 yr
    Pollutant: PM25
    
    Range (Min, Max):
    
    "Low" PM25 Communities
    
    (5.7-8.5)
    
    "High" PM2 5 Communities
    
    (13.7-29.5)
    
    Monitoring Stations: 12
    
    Copollutant: N02, acid vapor, PM10
    and elemental and OC correlated
    as a "non-03 package" of pollutants
    with a similar pattern relative to
    each other across the 12
    communities.
    PM Increment: NR
    
    IR Estimate [Lower Cl, Upper Cl]
    LowPM
    FVC Ł90:19.4(7.5, 50.5)
    FVC 90-110:16.8 (7.0, 40.1)
    FV0110: 7.9 (2.9, 21.9)
    FEV, Ł90:23.7(9.4, 59.4)
    FEV, 90-110:15.6 (6.5, 37.4)
    FEV, >110: 6.5 (2.3, 18.7)
    FEF25-75Ł90:21.1 (8.8,50.5)
    FEF25-75 90-110:11.9 (4.7, 30.0)
    FEF25-75>110: 6.4 (2.3, 18.2)
    Overall: 14.2 (7.0, 28.7)
    HighPM
    FVC Ł90:14.2 (5.1,39.6)
    FVC 90-110: 25.6 (11.1,59.2)
    FVC >110:16.7 (6.5, 42.9)
    FEV, Ł90: 20.8 (8.0, 54.0)
    FEV, 90-110: 23.1 (10.0,53.7)
    FEV,>110:18.8 (7.5, 47.3)
    FEF25-75Ł 90: 23.8 (10.2, 55.6)
    FEF25-75 90-110: 23.9 (9.9, 57.7)
    FEF25-75>110:15.9 (6.3, 40.5)
    Overall: 18.4 (9.4, 35.9)	
    Reference: Karretal.
    (2007, 0907191
    
    Period of Study:
    1995-2000
    
    Location: South Coast
    Air Basin of southern
    California
    Outcome: Bronchioloitis
    
    Study Design: Case-control.
    Cases included subjects with a
    record of a single hospitalization
    with a discharge diagnosis of acute
    bronchiolitis.10 controls per case
    were matched on birth date and
    gestational age.
    
    N: 18,595 cases
    169,472 controls
    
    Statistical Analyses: Conditional
    logistic regression to estimate
    relative risk of hospitalization for
    bronchiolitis.
    
    Covariates: Confounders included
    in the model were: gender, parity,
    chronic lung disease, cardiac and
    pulmonary anomalies, SES
    covariates
    
    Age, Gestational age, and season
    of birth were controlled for by
    matching
    
    Dose-response Investigated? Yes
    
    Statistical Package: STATA
    (Version 8)
    Pollutant: PM25
    
    Averaging Time: 24 h (lifetime
    monthly avg from birth & 30 days
    preceding cases hospitalization)
    
    Mean (SD): 25
    
    Percentiles:25th:19
    
    SOth(Median): 23
    
    75th: 29
    
    Range (Min, Max): 6 to 111
    
    Monitoring Stations: 17
    PM Increment: 10|jg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    
    Sub-chronic and chronic exposure: OR = 1.09 (1.04-1.14)
    
    Adjusted for adjusted: Sub-chronic OR = 1.10 (1.04,1.16)
    
    Chronic OR =1.09 (1.03-1.15)
    
    Adjusted for CO and  N02: Sub-chronic OR = 1.14 (1.07,1.21)
    
    Chronic OR =1.12 (1.06,1.20)
    
    Adjusted for 03, CO,  and N02: Chronic OR = 1.15 (1.08,1.22)
    
    Sub-chronic OR = 1.13 (1.06,1.21)
    Reference: (Kim etal.,
    2004, 0873831
    
    Period of Study:
    Mar-Jun (spring) 2001
    
    Sep-Nov (fall) 2001
    
    Location: Alameda
    County, CA
    Outcome: Asthma, bronchitis
    
    Age Groups: Children (grades 3-5)
    
    Study Design: Cross-sectional
    
    N: 1109 children, 871 (long term
    resident children), 462 (long term
    related females), 403 (long term
    related males)
    
    Statistical Analyses: 2-stage
    multiple logistic regression model
    
    Covariates: Respiratory illness
    before age of 2, household
    mold/moisture, pests, maternal
    history of asthma (for asthma)
    Season: spring and fall
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS 8.2
    Pollutant: PM25
    
    Averaging Time: 10 wk
    
    Mean (SD): Study Avg 12
    
    Monitoring Stations: 10
    
    Copollutant (correlation): r2 is
    approximately 0.9 for all
    copollutants-Black Carbon (BC),
    PM10, NOX, N02, NO (NOX-N02)
    PM Increment: 0.7 (IQR)
    
    OR Estimate [Lower Cl, Upper Cl]:
    Bronchitis
    All subjects: 1.02 [1.00,1.08]
    LTR subjects: 1.03 [1.01,1.08]
    LTR females: 1.04 [1.02,1.05]
    LTR males: 1.02 [0.99,1.05]
    Asthma
    All subjects: 1.00 [0.96,1.12]
    LTR subjects: 1.01 [0.97,1.06]
    LTR females: 1.06 [0.99,1.15]
    LTR males: 0.99 [0.95,1.04]
    Asthma excluding outlier school having a larger proportion of
    Hispanics
    All subjects: 1.04 [0.96,1.12]
    LTR subjects: 1.03 [0.94,1.13]
    LTR females: 1.03 [0.91,1.17]
    LTR males: 1.03 [0.94,1.18]
    December 2009
                                                 E-423
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95% Cl)
    Reference: Leonard! et
    al. (2000, 0102721
    
    Period of Study: 1996
    
    Location: 17 cities of
    Central Europe (Bulgaria,
    Czech Republic,  Hungary
    , Poland, Romania,
    Slovakia)
    Outcome: Immune biomarkers
    
    Age Groups: 9-11
    
    Study Design: Cross-sectional
    
    N: 366 school children
    
    Statistical Analyses: Linear
    regression
    
    Covariates: Age, gender, parental
    smoking, laboratory of analysis,
    recent respiratory illness
    
    Dose-response  Investigated? No
    
    Statistical Package: STATA
    Pollutant: PM25
    
    Averaging Time: Annual PM25
    
    Mean(SD):PM25:46(10)
    
    Range (Min, Max):
    
    PM25: (29, 67)
    
    5th, median, & 95th percentile
    
    PM25: 29, 44, 67
    % Change (Lower Cl, Upper Cl) p-value
    PM25
    Neutrophils-10(-45, 46)
    >20
    Total lymphocytes 49 (11,101); .008
    B lymphocytes 63 (4,155); .034
    Total T lymphocytes 72 (32
    123)
    <001
    CD4+  80 (34
    143)
    <001
    CD8+61 (17, 119); .003
    CD4/CD816(-17, 62)
    >20
    NK63(3, 158); .035
    Total IgG 24 (2, 52); .034
    Total IgM -9 (-32, 22)
    >20
    Total lgA-1 (-25, 32)
    >20
    TotallgE-4(-61, 137)
    >20
    Reference: McConnell
    (1999, 0070281
    
    Period of Study: 1993
    
    Location: Southern
    California
    Outcome: Bronchitis, chronic
    cough, phlegm
    
    Age Groups: Children: 4th, 7th, &
    10th graders
    
    Study Design: Cross-sectional
    
    N: 3676 people
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Age, sex, race, grade,
    health insurance
    
    Dose-response Investigated? Yes
    Pollutant: PM25
    
    Averaging Time: Yearly 2-wk avg
    
    Mean (SD): 15.3
    
    Range (Min, Max): 6.7, 31.5
    
    Copollutant (correlation):
    
    N02r = 0.83
    
    03r = 0.50
    
    Acid  r = 0.71
    Child Respiratory symptoms OR Estimate (Lower Cl,
    Upper Cl)
    
    PM2.s Increment: 15|jg/m3
    Children w/ asthma
    Bronchitis:  1.4 (0.9, 2.3)
    Phlegm: 2.6 (1.2, 5.4)
    Cough: 1.3 (0.7, 2.4)
    Children w/wheeze, no asthma
    Bronchitis:  0.9 (0.6,1.4)
    Phlegm: 1.0 (0.6,1.8)
    Cough: 1.1 (0.6,1.9)
    Children w/ no wheeze, no asthma
    Bronchitis:  0.5 (0.3,1.0)
    Phlegm: 0.8 (0.4,1.5)
    Cough: 0.9 (0.6,1.3)	
    Reference: McConnell et  Outcome: Bronchitic symptoms
    al. (2003, 0494901
            	        Age Groups: 9-19
    Period of Study:
    1993-1999              Study Design: Communities
                           selected on basis of historic levels
    Location: 12 Southern    of criteria pollutants and low
    CA communities         residential mobility.
    
                           N: 475 children
    
                           Statistical Analyses: 3 stage
                           regression combined to give a
                           logistic mixed effects model
    
                           Covariates: Sex, ethnicity, allergies
                           history, asthma history, SES,
                           insurance status, current wheeze,
                           current exposure to ETS, personal
                           smoking status, participation in
                           team sports, in utero tobacco
                           exposure through maternal
                           smoking, family history of asthma,
                           amount of time routinely spent
                           outside by child during 2-6 pm.
    
                           Dose-response Investigated? No
    
                           Statistical Package: SAS Glimmix
                                    Pollutant: PM25
    
                                    Averaging Time: 4-yr avg
    
                                    Mean (SD): 13.8(7.7)
    
                                    Range (Min, Max): 5.5-28.5
    
                                    Copollutant (correlation):
                                    PM10:r = 0.79
    
                                    PMi0.25:r = 0.24
    
                                    Inorganic acid: r = 0.76
    
                                    Organic Acid: r = 0.58
    
                                    EC: r = 0.83
    
                                    OC:r = 0.84
    
                                    N02:r = 0.54
    
                                    03:r = 0.72
                                    PM Increment: Between community range 23 pg/m
    
                                    Between community unit 1 pg/m3
    
                                    Within community 1 pg/m3
    
                                    OR Estimate [Lower Cl, Upper Cl]
    
                                    Between community per range
    
                                    1.81(1.14-2.88)
    
                                    Between Community per unit
    
                                    1.03(1.01-1.05)
    
                                    Within community per unit
    
                                    1.09(1.01-1.17)
    December 2009
                                                E-424
    

    -------
            Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
    Reference: McConnell et Outcome: Bronchitic symptoms
    al. (2003, 0494901
             	        Age Groups: 9-19
    Period of Study:
    1993-1999              study Design: Communities
                           selected on basis of historic levels
    Location: 12 Southern    of criteria pollutants and low
    CA communities         residential mobility.
    
                           N: 475 children
    
                           Statistical Analyses: 3 stage
                           regression combined to give a
                           logistic mixed effects model
    
                           Covariates: Sex, ethnicity, allergies
                           history, asthma history, SES,
                           insurance status, current wheeze,
                           current exposure to ETS, personal
                           smoking status, participation in
                           team sports, in utero tobacco
                           exposure through maternal
                           smoking,  family history of asthma,
                           amount of time routinely spent
                           outside by child during 2-6  pm.
    
                           Dose-response Investigated? No
    
                           Statistical Package: SAS Glimmix
                           macro
                               Pollutant: EC
    
                               Averaging Time: 4-yr avg
    
                               Mean (SD): 0.71(0.41)
    
                               Range (Min, Max): 0.1-1.2
    
                               Copollutant (correlation):
                               PM25:r = 0.83
    
                               PM10:r = 0.71
    
                               PM10.25:r = 0.30
    
                               Inorganic acid: r = 0.82
    
                               Organic Acid: r = 0.66
    
                               OC:r = 0.88
    
                               N02:r = 0.54
    
                               03:r = 0.68
                              PM Increment: Between community range 1.1 pg/m
    
                              Between community unit 1 pg/m3
    
                              Within community 1 pg/m3
    
                              OR Estimate [Lower Cl, Upper Cl]
    
                              Between community per range
    
                              1.64(1.06-2.54)
    
                              Between Community per unit
    
                              1.55(1.05-2.30)
    
                              Within community per unit
    
                              2.63(0.83-8.33)
    Reference: McConnell et Outcome: Bronchitic symptoms
    al. (2003, 0494901
                           Age Groups: 9-19
    Period of Study:
    1993-1999              study Design: Communities
                           selected on basis of historic levels
    Location: 12 Southern    of criteria pollutants and low
    CA communities         residential mobility.
    
                           N: 475 children
    
                           Statistical Analyses: 3 stage
                           regression combined to give a
                           logistic mixed effects model
    
                           Covariates: Sex, ethnicity, allergies
                           history, asthma history, SES,
                           insurance status, current wheeze,
                           current exposure to ETS, personal
                           smoking status, participation in
                           team sports, in utero tobacco
                           exposure through maternal
                           smoking,  family history of asthma,
                           amount of time routinely spent
                           outside by child during 2-6  pm.
    
                           Dose-response Investigated? No
    
                           Statistical Package: SAS Glimmix
                           macro
                               Pollutant: OC
    
                               Averaging Time: 4-yr avg
    
                               Mean (SD): 4.5(2.7)
    
                               Range (Min, Max): 1.4-11.6
    
                               Copollutant (correlation):
                               PM25:r = 0.84
    
                               PM,0:r=.70
    
                               PM10.25:r = 0.27
    
                               Inorganic acid: r = 0.83
    
                               Organic Acid: r = 0.69
    
                               EC: r = 0.88
    
                               N02:r = 0.67
    
                               03:r = 0.81
                              PM Increment: Between community range 10.2 pg/m
    
                              Between community unit 1 pg/m3
    
                              Wthin community 1 pg/m3
    
                              OR Estimate [Lower Cl, Upper Cl]
    
                              Between community per range
    
                              1.74(0.89-3.4)
    
                              Between Community per unit
    
                              1.06(0.99-1.13)
    
                              Wthin community per unit
    
                              1.41(1.12-1.78)
    December 2009
                                           E-425
    

    -------
    Study
    Reference: McConnell,
    et al. (2006, 1802261
    
    Period of Study:
    ^ one ^ nnn
    1990-1999
    Location: 12 Southern
    California communities
    
    
    Design & Methods
    Outcome:
    
    Prevalence of bronchitic symptoms
    (yrly).
    Age Groups: 10-15-yr-old
    Study Design: Longitudinal cohort
    N: 475 asthmatic children
    Ct-atiotirt'al AnalwoAO1 Mi iltllawal
    Concentrations1
    Pollutant: PM25
    
    Averaging Time: 365 days
    Percentiles: Community byyr
    (n = 48 = 12 communities • 4 yr)
    25th: NR
    SOth(Median): 3.4
    75th: NR
    
    Range (Min, Max): Community by
    Effect Estimates (95%
    PM Increment: 3.4 pg/m3
    
    OR Estimate [Lower Cl, Upper Cl]
    PM25
    Dog (n = 292): 1.56 [1.15: 2.12]
    No dog (n = 183): 1.03 [0.71: 1.49]
    PM25*Dog interaction p-value: 0.06
    Cat (n = 202): 1.30 [0.90: 1.88]
    No Cat (n = 273): 1.36 [0.99: 1.83]
    PM25*Cat interaction p-value: 0.87
    Cl)
    
    
    
    
    
    
    
                            Statistical Analyses: Multilevel
                            logistic mixed effects models.
    
                            Covariates: Age, second-hand
                            smoke
    
                            Personal smoking history
    
                            Sex, race.
    
                            Dose-response Investigated? No
    
                            Statistical Package: SAS
    yr (n = 48 = 12 communities • 4 yr):
    (0.89, 8.7)
    
    Monitoring Stations: 12
    
    Copollutant:
    03
    N02
    EC
    OC
    Acid vapor (acetic and formic acid)
    Neither pet (n = 112): 1.11 [0.71:1.74]
    Cat only (n = 71): 0.85 [0.46:1.57]
    Dog only (n = 161): 1.53 [1.04: 2.25]
    Both pets (n = 131): 1.58 [1.02: 2.46]
    Results suggest that dog ownership, a source of residential
    exposure to endotoxin, may worsen the severity of respiratory
    symptoms from exposure to air pollutants in asthmatic
    children.
    
    Although PM25 was associated at a statistically significant
    level with ownership of both cats and dogs, it appears that dog
    ownership (with or without a cat) specifically worsens the
    association between PM25 and respiratory symptoms in
    asthmatic children.
    Reference: (Mengetal.,
    2007, 0932751
    Period of Study: Nov
    2000 and Sep 2001
    Location: Los Angeles
    and San Diego counties
    Outcome: Poorly controlled asthma Pollutant: PM25
    vs. controlled asthma
    Averaging Time: 24 h
    ICD9NR
    Copollutant (correlation):
    Age Groups: 18-64, 65+ ^^
    Study Design: Long-term exposure ^^
    comparison of cases and controls PMio: r = 0.84
    N: 1,609 adults (represented CO: r = 0.52
    individuals age 1 8+ who reported jQ' r - 0 1 3
    Results for PM25 were nonsignificant and not reported
    quantitatively.
                            having asthma by a physician and
                            had their address successfully
                            geocoded)
    
                            Statistical Analyses: Logistic
                            regression to evaluate associations
                            between TD (traffic density) and
                            annual avg air pollution
                            concentrations and poorly
                            controlled asthma. Used sample
                            weights that adjusted for unequal
                            probabilities of selection into the
                            CHIS sample.
    
                            Covariates: Age, sex,
                            race/ethnicity, family federal poverty
                            level, county, insurance status,
                            delay in care for asthma, taking
                            medications, smoking behavior,
                            self-reported health status,
                            employment, physical activity
    
                            Dose-response  Investigated? yes
    December 2009
                 E-426
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95% Cl)
    Reference: Millstein, J et  Outcome: Wheezing & asthma
    al. (2004, 0886291        medication use (ICD 9 NR)
    Period of Study:
    Mar-Aug 1995, and Sep
    1995-Feb1996
    Data were taken from the
    Children's Health Study
    Location: Alpine,
    Atascadero, Lake
    Arrowhead, Lake
    Elsinore, Lancaster,
    Lompoc, Long Beach,
    Mira Loma,  Riverside,
    San Dimas, Santa Maria,
    and Upland, CA
    Age Groups: 4th grade students,
    mostly 9 yr at the time of the study
    Study Design: Cohort Study,
    stratified into 2 seasonal groups/
    N: 2081 enrolled, 2034 provided
    parent-completed questionnaire.
    Statistical Analyses: Multilevel,
    mixed-effects logistic model.
    Covariates: Contagious respiratory
    disease, ambient airborne pollen
    and other allergens, temperature,
    sex, age race, allergies, pet cats,
    carpet in home, environmental
    tobacco smoke, heating fuel,
    heating system, water damage in
    home, education level of
    questionnaire signer, physician
    diagnosed asthma.
    Season: Mar-Aug, 1995,  and Sep,
    1995toFeb, 1996
    Statistical Package: GLIMMIX
    SAS 8.00 macro for generalized
    linear mixed models.
    Lags Considered: 14
    Pollutant: PM25
    Averaging Time: Integrated values
    for successive 2-wk periods
    PM Component: Nitric acid, formic
    acid, acetic acid
    Monitoring Stations: 1 central
    location in each community
    Copollutant (correlation):
    03:r = 0.09
    N02:r = 0.28
    PM10:r = 0.33
    PMi0.25:r = -0.08
    PM Increment: IQR: 5.24 pg/rri
    Odds Ratio [lower Cl, Upper Cl]
    Annual
    PM25:1.04 [0.83, 1.29]
    Mar-Aug
    PM25:0.91 [0.64, 1.30]
    Sep-Feb
    PM25:1.18 [0.89, 1.58]
    Reference: Morgenstern
    et al. (2007, 0907471
    Period of Study: Mar
    1999-Jul2000
    Location: Munich,
    Germany
    Outcome: Asthma, wheezing,
    spastic/obstructive bronchitis. Dry
    cough at night, respiratory
    infections,  sneezing, runny/stuffed
    nose without a cold.
    Age Groups: at 1 yr & at 2 yr
    Study Design: Cohort
    N: 3577 children for the prediction
    models. Respiratory data available
    for 3129 children at 1 yr.
    Statistical Analyses: Pearson's
    correlation coefficient, prediction
    error expressed as root mean
    squared error (RMSE), multiple
    logistic regression with confounding
    factors, odds ratios
    Covariates: Sex, Parental atopy
    (genetic predisposition to allergies),
    environmental tobacco smoke at
    home, maternal education >or <12
    yr, sibling,  gas stove, home
    dampness, indoor mold,  pets. Since
    it was not feasible to measure
    personal exposure to N02, PM25,
    and PM25 absorbance, exposure
    modeling was used.
    Statistical Package: SAS V.8.02
    Pollutant: PM25
    Averaging Time: Annual
    Mean (SD): 12.8
    Percentiles: 25th: 12.5
    SOth(Median): 12.9
    75th: 13.3
    Range (Min, Max):  6.8,15.3
    Monitoring Stations: 40: traffic,
    n = 17 and background,  n = 23.
    Copollutant (correlation):
    P M2 5 absorbance r  = 0.49
    NO, r = 0.45
    PM Increment: 1.04 pg/m
    Odds Ratio [Lower Cl, Upper Cl]
    Adjusted OR for PM25 and: sneezing, runny/stuffed nose
    during the first yr of life was 1.16 [1.01,1.34]
    At age 1 yr
    For wheezing 1.01 [0.87,1.18]
    For cough without infection 1.05 [0.88,1.25]
    For dry cough at night! .08 [0.86,1.27]
    For asthmatic, spastic, or obstructive bronchitis
    1.04 [0.90, 1.29]
    For respiratory infectionl.05 [0.88,1.22]
    For sneezing, runny or stuffed nose 1.16 [1.01,1.34]
    At age 2 yr
    For wheezing 1.10 [0.96,1.25]
    For cough without infection NA, insufficient sample
    For dry cough at night 1.03 [0.86,1.19]
    For asthmatic, spastic, or obstructive bronchitis
    1.05 [0.92,1.20]
    For respiratory infection 1.09 [0.94,1.07]
    For sneezing, runny or stuffed nose 1.19 [1.04,1.36]
    December 2009
                                                 E-427
    

    -------
            Study
          Design & Methods
           Concentrations1
                 Effect Estimates (95% Cl)
    Reference: Morgenstern
    et al. (2007, 0907471
    Period of Study: May
    1999-Jul2000
    Location: Munich,
    Germany
    Outcome: Asthma, wheezing,
    spastic/obstructive bronchitis. Dry
    cough at night, respiratory
    infections,  sneezing, runny/stuffed
    nose without a cold.
    Age Groups: at 1 yr & at 2 yr
    Study Design: Cohort
    N: 3577 children for the prediction
    models. Respiratory data were
    available for 3129 children at 1 yr.
    Statistical Analyses: Pearson's
    correlation coefficient, prediction
    error expressed as root mean
    squared error (RMSE), multiple
    logistic regression with confounding
    factors, odds ratios
    Covariates: Sex, Parental atopy
    (genetic predisposition to allergies),
    environmental tobacco smoke at
    home, maternal education >or <12
    yr, sibling,  gas stove, home
    dampness, indoor mold,  pets. Since
    it was not feasible to measure
    personal exposure to N02, PM25,
    and PM25 absorbance, exposure
    modeling was used.
    Statistical Package: SAS V.8.02
    Pollutant: PM25 Absorbance (PM25
    ab)
    Averaging Time: Annual
    Mean(SD):1.710-5m-1,
    Percentiles:25th:1.610-5m-1
    50th(Median):1.710-5m-1
    75th: 1.8 10 -5 m-1
    Range (Min, Max):
    1.3, 3.2 10-5 m-1
    Unit(i.e. ug/m3): 10-5 m-1
    Monitoring Stations: 40: traffic,
    n = 17 and background, n = 23.
    PM Increment: 0.22x10-5
    Odds Ratio [Lower Cl, Upper Cl]
    no lag
    At age 1 yr
    For wheezing 0.97 [0.77,1.23]
    For cough without infection 1.16[0.87,1.54]
    For dry cough at night! .09 [0.78,1.51]
    For asthmatic, spastic, or obstructive bronchitis
    1.14 [0.88,1.48]
    For respiratory infections'! .03 [0.86,1.24]
    For sneezing, runny or stuffed nose 1.30 [1.03,1.1
    At age 2 yr
    For wheezing 1.09 [0.90,1.33]
    For cough without infection NR insufficient data
    For dry cough at night!. 18 [0.93,1.50]
    For asthmatic, spastic, or obstructive bronchitis
    0.85 [0.30, 2.34]
    For respiratory infections'! .05 [0.79,1.39]
    For sneezing, runny or stuffed nose
    1.27 [1.04,1.56]
    Reference: Oftedal et al.
    (2008, 0932021
    Period of Study:
    2001-2002
    Location: Oslo, Norway
    Outcome: Lung function (PEF,
    FEF25%, FEF50%, FEV,, FVC)
    Age Groups: 9-1 Oyr
    Study Design: Cross-sectional
    N: 1847 children
    Pollutant: PM25
    IQR:
    PM2 5 in 1st yr of life: 6.2
    PM25 lifetime: 3.6
    PM Increment: Per IQR
    P (Lower Cl, Upper Cl)
    PM25in1styroflife
    PEF -76.1 (-122.2(0-30.0)
                            Statistical Analyses: Linear
                            regression
                            Covariates: Height, age, BMI, birth
                            weight, temperature, maternal
                            smoking, se
                            Dose-response Investigated? Yes
                            Statistical Package: SPSS,
                            STATA, S-Plus
                            Lags Considered: 1-3
                                                                      FEF25%-75.6 (-127.4 to-23.8)
                                                                      FEF 50%-62.4 (-107.4 to-17.4)
                                                                      FEV, -12.7 (-28.8, 3.4)
                                                                      FVC-2.9 (-20.5, 14.7)
                                                                      PM25 lifetime exposure
                                                                      PEF-57.7 (-94.4(0-21.1)
                                                                      FEF25%-51.8 (-93.1  to-10.6)
                                                                      FEF 50%-48.4 (-84.2 to-12.6)
                                                                      FEV,-10.4 (-23.2, 2.4)
                                                                      FVC-3.9 (-17.9, 10.1)
    Reference: (Parker et
    al., 2009, 1923591
    Period of Study: 1999-
    2005
    Location: U.S.
    Outcome: Respiratory
    allergy/hayfever
    Study Design: Cohort
    Covariates: Survey yr, age, family
    structure, usual source of care,
    health insurance, family income
    relative to federal poverty level,
    race/ethnicity
    Statistical Analysis: Logistic
    regression
    Statistical Package: SUDAAN
    Age Groups: 73,198 children aged
    3-17 yr
    Pollutant: PM25
    Averaging Time: NR
    Median: 13.1
    IQR: 10.9-15.2
    Copollutant (correlation):
    Summer 03: 0.10
    S02: 0.21
    N02: 0.53
    PM,0.2.5: 0.02
    PM10:0.51
    Increment: 10 pg/m3
    Odds Ratio (96% Cl)
    Single Pollutant Model, variable N
    Adjusted: 1.16 (1.04-1.30)
    Single Pollutant Model, constant N
    Adjusted: 1.23 (1.04-1.46)
    Multi-pollutant Model:  1.29 (1.07-1.56)
    December 2009
                                                 E-428
    

    -------
    Study
    Reference: Sekine et al.
    (2004, 0907621
    Period of Study:
    1987-1994
    Location: Nine districts
    in the Tokyo, Japan
    metropolitan area: Chuo
    ward, Ohta ward,
    Shibuya ward, Itabashi
    ward, Hachioji City,
    Tachikawa City, Om e
    City, Machida City,
    Tanashi City
    
    
    
    
    
    Reference: Sharma et
    al. (2004, 1569741
    
    Period of Study: Nov
    2002-Apr2003
    Location: 3 sections in
    KanpurCity, India
    1) Indian Institute of
    Technology Kanpur (I ITK)
    2) Vikas Nagar (VN)
    3) Juhilal Colony (JC)
    
    
    
    
    
    
    Reference: (Singh etal.,
    2003, 0526861
    Period of Study: NR
    
    Location: Jaipur, India
    
    
    
    Design & Methods
    Outcome: Pulmonary function tests
    Age Groups: 30-59 yr
    Study Design: Cross-sectional and
    longitudinal
    
    N: 500 females
    Statistical Analyses: Multiple
    logistic regression analysis
    Covariates: Group (classification
    by air pollution level), pulmonary
    function at initial test, age and
    height at the time of the initial test,
    number of yr investigated, yr of
    residence in the area, type of
    heater, housing structure, and job
    status
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    Outcome: Lung function
    
    Age Groups: 20-55 yr
    
    Study Design: Cohort
    N: 91 people
    Statistical Analyses: Linear
    regression
    Covariates: NR
    Season: Fall, Winter, spring
    Dose-response Investigated? No
    Statistical Package:
    Microsoft Excel
    Lags Considered: 1 day lag &
    5-day ma
    
    
    Outcome: Lung function (peak
    expiratory flow variability)
    Age Groups: Medical school-aged
    students
    
    Study Design: Cross sectional
    N: 313 nonsmoker students
    
    Concentrations1
    Pollutant: Suspended PM (SPM)
    Averaging Time: Measured each
    month for three consecutive days
    (72 h)
    Mean (SD): 28. 1-63.3
    Range (Min, Max): 3.4-140.6
    Copollutant (correlation): N0;
    
    
    
    
    
    
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean(SD):IITK158(22)
    VN 85 (30)
    JC 59 (9)
    PM Component: Lead, Nickel,
    Cadmium, Chromium, Iron, Zinc
    Benzene soluble fraction (includes
    polycyclic aromatic hydrocarbons
    [PAHs])
    Copollutant (correlation):
    APEF = mean daily deviations in
    PEF
    PM25-APEF: -0.30
    PM25-PM10: 0.67
    PM25-PMio (1-day lag): 0.49
    PM25-PM25 (1-day lag): 0.88
    Pollutant: Respirable suspended
    PM (RSPM)
    Averaging Time: 8 h
    
    Mean (SD): Roadside: 1,666
    Campus: 177
    
    Monitoring Stations: 2
    Effect Estimates (95% Cl)
    Results of multiple logistic regression analysis for respiratory
    symptoms
    Persistent cough
    Group 3: OR = 1.00
    Group 2: OR =1.02 (0.70-1. 48)
    Group 1: OR =1.07 (0.67-1. 70)
    Persistent phlegm
    Group 3: OR =1.00
    Group 2: OR =1.51 (1.11-2.04)
    Group 1:OR= 1.78 (1.26-2.53)
    Asthma
    Group 3: OR = 1.00
    Group 2: OR =1.99 (0.82-4.83)
    Group 1: OR = 2.66 (0.98-7.19)
    Wheeze
    Group 3: OR = 1.00
    Group 2: OR =1.39 (0.95-2.01)
    Group 1:OR= 1.34 (0.85-2.11)
    Breathlessness
    Group 3: OR =1.00
    Group 2: OR = 0.84 (0.47-1.50)
    Group 1: OR = 2.70 (1.48-4.91)
    PM Increment: 1 pg/m3
    
    APEF (difference or change in peak expiratory flow)
    
    -0.0297 L/min
    
    
    
    
    
    
    
    
    
    
    
    It appears that no associations between particulates and the
    outcome of interest were calculated and reported in this study
    
    
    
    
    
    
                           Statistical Analyses: Amplitude %
                           mean was used as the measure of
                           PEF variability. Mean value of
                           amplitude % mean of peak flow
                           variability were compared for in the
                           two groups by application of
                           Student's t-test. The two groups
                           were: living on campus and
                           commuters.
    
                           Dose-response Investigated? Yes
    December 2009
    E-429
    

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    Study
    Reference: (Solomon et
    al, 2003, 0874411
    Period of Study:
    1966-1997
    Location: United
    Kingdom: Northern
    England, North-West
    Midlands, and V\feles.
    Design & Methods
    Outcome: Cardio-respiratory
    morbidity
    Age Groups: 45 yr and older
    Study Design: Cross-sectional
    N: 1,1 66 women
    Statistical Analyses: Prevalence
    Concentrations1
    Pollutant: Black Smoke
    Averaging Time: Annual
    Effect Estimates (95% Cl)
    RR Estimate [Lower Cl, Upper Cl]
    The findings provide no indication that prolonged residence in
    places that have had relatively high levels of particulate air
    pollution causes an important increase in cardio-respiratory
    morbidity.
    Prevalence ratios are based on high vs. low pollution with low
    as referent.
                            heart disease, asthma, productive
                            cough, wheeze, and use of an
                            inhaler for asthma or other breathing
                            problems.
    
                            Covariates: Smoked,  passive
                            smoking in childhood,  tenancy, SES,
                            worked in industry with respiratory
                            hazards, childhood admission to
                            hospital for chest problem, diabetes,
                            BMI were all controlled for as
                            potential confounders.
    
                            Dose-response Investigated? yes
    
                            Statistical Package: STATA
                                                                      Particulate pollution in place of residence:
    
                                                                      Rr = 1.0 (0.7-1.4) for ischemic heart disease;
    
                                                                      Rr = 0.7 (0.5-1.0) for asthma
    
                                                                      Rr = 1.0 (0.7 -1.5) for productive cough
    Reference: Suglia et al.
    (2008, 1570271
    
    Period of Study: Mar
    1986-0ct1992
    Location: Boston, MA
    
    
    
    
    
    
    
    
    
    Outcome: Lung function Pollutant: Black Carbon (BC)
    
    Age Groups: 18-42 Averaging Time: Annual
    Study Design: Prospective cohort Mean (SD): 0.62 (0.15)
    N: 272 women of childbearing age
    
    Statistical Analyses: Linear
    regression
    Covariates: Height, age, weight,
    race/ethnicity, yr, education
    Dose-response Investigated?
    yes-tertiles of exposure
    Statistical Package: SASv. 9.0
    
    
    PM Increment: 0.22 pg/m3 (IQR)
    
    Effect Estimate [Lower Cl, Upper Cl]
    FEV,: -1.08 (-2.5, 0.3)
    FVC: -0.62 (-1.9, 0.6)
    FEF25-75%:-2.97(-5.8to-0.2)
    Current Smokers:
    FEV,: 0.62 (-2. 1,3.4)
    FVC: 0.64 (-2.0, 3.3)
    FEF25-75%: -2.63 (-3.7, 8.9)
    Former Smokers1
    FEVi:-4.40(-7.8to-1.0)
    FVC: -3. 11 (-6.1(0-0.2)
    FEF25-75%: -8.78 (-14.7 to -2.9)
    Nonsmokers:
    FEV,: -0.98 (-2.9, 0.9)
    FVC: -0.32 (-2.0, 1.4)
    FEF25-75%:-4.39(-8.1to-0.6)
                                                                                              Exposure-response relationship presented graphically in Fig
                                                                                              1: the highest BC exposure group had decreases in FEV,,
                                                                                              FVC, and FEF25-75% compared with the lowest fertile group,
                                                                                              although these differences were not statistically significant.
    Reference: (Sunyer et
    al., 2006, 0897711
    
    Period of Study: initial
    selection: 1991-1993,
    follow-up Jun 2000-Dec
    2001
    
    Location: 21 centers in
    10 European countries
    Outcome: Chronic bronchitis
    
    Age Groups: Mean age (range)
    
    Males-42.62 (38.12-45.62)
    
    Females- 42.57 (39.92-45.69)
    
    Study Design: Hierarchical models
    
    N:6924
    
    Statistical Analyses: General
    additive models (GAM)
    
    Covariates: Smoking, age at end of
    education, occupational group,
    occupational exposures, respiratory
    infections during childhood, rhinitis,
    asthma, traffic intensity at household
    level.
    
    Statistical Package: STATA-8
    Pollutant: PM25
    
    Averaging Time: 18 mo
    
    Mean (SD): 3.7-44.9
    
    Copollutants: N02, S02
    PM Increment: NR
    
    Odds ratio [Lower Cl, Upper Cl]
    
    Chronic phlegm prevalence at follow up
    
    Males: 0.97 [0.70,1.35]
    December 2009
                                                  E-430
    

    -------
    Study
    Reference: Zhang et al.
    (2002, 0348141
    Period of Study:
    1993-1996
    Location: 4 Chinese
    cities (urban and
    suburban location in
    each city): Guangzhou,
    Wuhan, Lanzhou,
    Chongqing
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Interview-self reports of
    symptoms: Wheeze (ever wheezy
    when having a cold)
    Asthma (diagnosis by doctor)
    Bronchitis (diagnosis by doctor)
    Hospitalization due to respiratory
    disease (ever)
    Persistent cough (coughed for at
    least 1 month per yr with or apart
    from colds)
    Persistent phlegm (brought up
    phlegm or mucus from the chest for
    at least 1 month per yr with or apart
    from colds).
    Age Groups: Elementary school
    students
    age range: 5.4-16.2
    Study Design: Cross-sectional
    N: 7,557 returned questionnaires
    Concentrations1
    Pollutant: PM25
    Averaging Time: 2 yr
    Mean (SD): 92 (31)
    Percentiles:
    25th: NR
    SOth(Median): NR
    75th: NR
    IQR: 39
    Range (Min, Max):
    
    Gives range (max.-min.):
    PM25-98
    Monitoring Stations: 2 types:
    municipal monitoring stations over
    a period of 4 yr (1993-1996)
    schoolyards of participating
    children over a period of 2 yr
    (1995-1996)
    Effect Estimates (95% Cl)
    
    PM Increment: Interquartile range corresponded to 1 unit of
    change.
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    No association between PM25 and any type of respiratory
    morbidity.
    
    
    
    
    No between or within city association between PM25 and any
    type of respiratory morbidity.
    When scaled to an increment of 50 pg/m3 increase in PM25,
    association (ORs) between respiratory outcome and PM25
    was:
    
    Wheeze: 1.06
    Asthma: 1.29
    Bronchitis: 1.68
    Hospitalization: 1.08
    Persistent cough: 1.24
    Persistent phlegm: 3.09
    
    
    
    
    
    
    
    
                            7,392 included in first stage of
                            analysis
    
                            Statistical Analyses: 2-stage
                            regression approach:
    
                            Calculated odds ratios and 95% CIs
                            of respiratory outcomes and covari-
                            ates Second stage consisted of vari-
                            ance-weighted linear regressions
                            that examined associations between
                            district-specific adjusted prevalence
                            rates and district-specific ambient
                            levels of each pollutant.
    
                            Covariates: Age,  gender, breast-fed,
                            house type, number of rooms,
                            sleeping in own or shared room,
                            sleeping in own or shared bed,  home
                            coal use, ventilation device used,
                            homes smokiness during cooking,
                            eye irritation during cooking, parental
                            smoking, mother's education level,
                            mother's occupation, father's
                            occupation, questionnaire
                            respondent, yr of questionnaire
                            administration, season of question-
                            naire administration, parental asthma
                            prevalence.
    All units expressed in pg/m unless otherwise specified.
    December 2009
    E-431
    

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    Table E-25.    Long-term exposure - respiratory morbidity outcomes - other PM size fractions.
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: El-Zein et al. (2007,
    0930431
    
    Period of Study: 2000-2004
    
    Location: Beirut, Lebanon
    ED Admissions
    
    Outcome: Acute respiratory symptoms:
    asthma, URTI, pneumonia, bronchitis
    
    Age Groups: <17
    
    Study Design: Ecological (natural
    experiment comparing admissions
    before and after ban on diesel fuel)
    
    N: 5 hospitals, 7573 admissions Oct-
    Feb, 4303 admissions Oct-Dec
    
    Statistical Analyses: T-test, Poisson
    regression
    
    Covariates: Month of Year,
    temperature, humidity, orthogonalized
    rainfall
    
    Season: Oct-Dec (excluding flu
    season) and Oct-Feb
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: 1-2 yr before the
    ban compared to 1-2 yr after the ban
    Pollutant: PM from diesel
    
    Range (Min, Max): NR
    
    PM Component: NR
    
    Monitoring Stations: 1
    
    Notes: Did not look at specific
    exposure data
    
    looked at outcome with respect to a
    timeline that plotted admissions before
    and after a ban on diesel fuel.
    
    Copollutant: NR
    PM Increment: NA
    
    |3 (p-value):
    2-yr pre-ban vs. 2-yr post-ban
    Oct to Feb
                                                                                                              AIIResp:0.128
                  0.32
                  0.16
                                                                                                              Asthma:-0.176
                                                                                                              Bronchitis: 0.505 (0.02)
                                                                                                              Pneumonia: 0.287 (0.17)
                                                                                                              URTI:-0.265 (0.41)
                                                                                                              Oct to Dec
                                                                                                              All Resp: -0.022 (0.87)
                                                                                                              Asthma: -0.21  (0.07)
                                                                                                              Bronchitis: 0.2 (0.35)
                                                                                                              Pneumonia: -0.065 (0.78)
                                                                                                              URTI: -0.628 (0.05)
                                                                                                              2-yr pre-ban vs. 1-yr post-ban
                                                                                                              Oct-Feb
                                                                                                              All Resp: -0.093 (0.45)
                                                                                                              Asthma: -0.208 (0.05)
                                                                                                              Bronchitis: 0.286 (0.32)
                                                                                                              Pneumonia: -0.07 (0.76)
                                                                                                              URTI:-0.715 (0.11)
                                                                                                              Oct to Dec
                                                                                                              All Resp:-0.147 (0.02)
                                                                                                              Asthma:-0.147 (0.00)
                                                                                                              Bronchitis: -0.011 (0.96)
                                                                                                              Pneumonia:-0.214 (0.15)
                                                                                                              URTI: -0.885 (0.06)
                                                                                                              1-yr pre-ban vs. 1-yr post-ban
                                                                                                              Oct-Feb
                                                                                                              All Resp:-0.165 (0.04)
                                                                                                              Asthma: -0.212 (0.09)
                                                                                                              Bronchitis: 0.059 (0.85)
                                                                                                              Pneumonia: -0.034 (0.84)
                                                                                                              URTI:-1.023 (0.00)
                                                                                                              Oct to Dec
                                                                                                              All Resp:-0.17 (0.00)
                                                                                                              Asthma:-0.131 (0.00)
                                                                                                              Bronchitis:-0.145 (0.001)
                                                                                                              Pneumonia:-0.168 (0.12)
                                                                                                              URTI:-1.036 (0.00)	
    Reference: Kasamatsu et al. (2006,
    1566271
    Period of Study: 2001-2002
    
    Location: Shenyang, China
    Outcome: FVC, FEV,, PEF, FEF75     Pollutant: PM7
    Age Groups: School Children aged 8-
    10
    
    Study Design: Children in three
    schools in three types of areas
    (commercial city area, residential city
    area, residential suburban area) invited
    to participate
    
    N: 322 children participated, 244 have
    complete data.
    
    Statistical Analyses: Genralized
    estimating equations
    
    Covariates: Age,  height,
    
    Dose-response Investigated? No
    
    Statistical Package: SAS
    
    Lags: Considered: previous quarter.
    Averaging Time: Avg of 4 separate 2-7
    consecutive day measurements within
    each designated measurement month
    of the quarter
    Mean (SD):
    School A
    7/2001 86.4(14.2)
    10/2001 114.1(35.1)
    1/2002 118.2(28.2)
    4/2002 182.7(102.1)
    School B
    7/2001 90.1(8.3)
    10/2001 161.5(45.7)
    1/2002 118.8(28.2)
    4/2002152.0(31.3)
    School C
    7/2001 78.1(16.9)
    10/2001 131.2(29.6)
    1/2002 142.2(37.6)
    4/2002173.6(121.5)
    PM Component: mainly pollutants
    associated with coal heating
    
    Monitoring Stations: 1  at each location
    PM Increment: 63.0 pg/m
    
    Mean change of pulmonary function
    value [Lower Cl, Upper Cl] at lag 0
    Boys
    FVC-0.095(-0.170,-0.019)
    FEVi-0.088(-0.158,-0.019)
    PEF-0.170(-0.365,0.032)
    FEF75-0.063(-0.183,0.050)
    Girls
    FVC-0.082(-0.145,-0.019)
    FEV,-0.069(-0.126,-0.006)
    PEF0.095(-0.095,0.290)
    FEF75-0.032(-0.151,0.082)
    Mean change of pulmonary function
    value [Lower Cl, Upper Cl] at lag
    1 (previous quarter)
    Boys
    FVC-0.145(-0.189,-0.095)
    FEV1-0.095(-0.139,-0.057)
    PEF-0.082(-0.208,0.050)
    FEF750.013(-0.063,0.088)
    Girls
    FVC-0.126(-0.170,-0.088)
    FEVi-0.101(-0.139,-0.063)
    PEF-0.101(-0.227,0.025)
    FEF75-0.057(-0.132,0.019)	
    December 2009
                                    E-432
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Kasamatsu et al.(2006,
    1566271
    
    Period of Study: 2001-2002
    
    Location: Shenyang, China
    Outcome: FVC, FEV,, PEF, FEF75
    
    Age Groups: School Children aged 8-
    10
    
    Study Design: Children in three
    schools in three types of areas
    (commercial city area, residential city
    area, residential suburban area) invited
    to participate
    
    N: 322  children participated, 244 have
    complete data.
    
    Statistical Analyses: Genralized
    estimating equations
    
    Covariates: Age, height,
    
    Dose-response Investigated? no
    
    Statistical Package: SAS
    
    Lags: Considered: previous quarter.
    Pollutant: PM2,
    
    Averaging Time: Avg of 4 separate 2-7
    consecutive day measurements within
    each designated measurement month
    of the quarter
    Mean (SD):
    School A
    7/2001 47.6(6.4)
    10/2001  54.2(20.5)
    1/200268.9(15.8)
    4/2002 115.8(76.7)
    School B
    7/2001 45.6(6.5)
    10/2001  74.4(27.1)
    1/200263.3(17.9)
    4/2002 96.3(27.6)
    School C
    7/2001 42.5(9.5)
    10/2001  59.7(13.1)
    1/200276.4(22.1)
    4/2002 123.0(100.9)
    PM Component: mainly pollutants
    associated with coal heating
    
    Monitoring Stations: 1 at each location
    PM Increment: 42.1 pg/m
    
    Mean change of pulmonary function
    value [Lower Cl, Upper Cl] at lag 0
    Boys
    FVC-0.126(-0.181,-0.076)
    FEV1-0.122(-0.173,-0.076)
    PEF-0.164(-0.303,-0.025)
    FEF75-0.046(-0.131,0.038)
    Girls
    FVC-0.110(-0.156,-0.067)
    FEVi-0.101(-0147,-0.059)
    PEF0.008(-0.131,0.147)
    FEF75-0.055(-0.139,0.030)
    Mean change of pulmonary function
    value [Lower Cl, Upper Cl] at lag
    1 (previous quarter)
    Boys
    FVC-0.099(-0.145,-0.053)
    FEV1-0.059(-0.106,-0.020)
    PEF-0.040(-0.158,0.086)
    FEF750.026(-0.046,0.092)
    Girls
    FVC-0.086(-0.125,-0.046)
    FEVi-0.066(-0.106,-0.026)
    PEF-0.079(-0.198,0.040)
    FEF75-0.033(-0.106,0.040)
    All units expressed in pg/m unless otherwise specified.
    December 2009
                                    E-433
    

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    E.6. Long-Term  Exposure  and  Cancer
    Table E-26.    Long-term exposure - cancer outcomes - PMio.
                 Study
           Design & Methods
            Concentrations
       Effect Estimates (95% Cl)
    Reference: (Abbey et al, 1999,
    0475591
    
    Period of Study: 1977-1992
    
    Location: California
    Outcome (ICD9): Lung Cancer
    Mortality (162)
    
    Age Groups: 27-95 at baseline
    
    Study Design: Cohort (AHSMOG)
    
    N: 6,338 nonsmoking CA Seventh-Day
    Adventists
    
    Statistical Analyses: Time-dependent,
    gender-specific, Cox proportional
    hazards regression models
    
    Covariates: Age, smoking, education,
    occupation, BMI
    Pollutant: PM10
    
    Averaging Time: Monthly estimates
    from 1966-1992
    
    Mean (SD): 51.24 (16.63)
    
    Percentiles: IQR: 24.08
    
    Range (Min, Max): 0, 83.9
    Correlations:
    S04:r = 0.68)
    S02:r = 0.31
    03:r = 0.77
    N02:r = 0.56
    
    Lag:3 yr
    PM Increment: 24.08 (IQR)
    
    RR, males: 3.36 [1.57, 7.19]
    
    RR, females: 1.33 [0.60, 2.96]
    
    PM10 above 100ug/m3 (days peryr)
    
    IQR: 43 days/yr
    
    Males: 2.38 (1.42, 3.97)
    
    Females: 1.08 (0.55, 2.13)
    Reference: Beeson et al. (1998,
    0488901
    
    Period of Study: 1977-1992
    
    Location: California
    Outcome (ICD9: Lung Cancer Mortality  Pollutant: PM
    (ICDO-1:162, ICDO-2: C34.0-C34.9)
    Age Groups: 27-95 at baseline
    
    Study Design: Cohort (AHSMOG)
    
    N: 6,338 nonsmoking CA Seventh-Day
    Adventists (non-Hispanic white)
    
    Statistical Analyses: Time-dependent,
    gender-specific, Cox proportional
    hazards regression models
    
    Covariates: Smoking, Education, Age,
    Alcohol
    
    Statistical Package:  SAS
    
    Lags Considered: 3 yr
    Averaging Time: Averaged monthly
    estimates from 1966-1992
    
    Mean (SD): 51 (16.52)
    
    Percentiles: IQR: 24
    
    Range (Min, Max): 0, 84
    PM Increment: 24 (IQR)
    
    RR, males: 5.21 [1.94,13.99]
    
    RR, females: Positive, but not
    statistically significant
    Reference: Binkova et al. (2007,
    1562731
    Period of Study: Feb 2001
    
    Location: Prague, Czech Republic
    Outcome: Total DNAadducts (bulky
    aromatic PAH-DNAadducts and ...
    
    Age Groups: 22-50 yr
    
    Study Design: Case Control
    
    N: 53 occupationally exposed
    policemen and 52 control policemen
    
    Statistical Analyses: Multivariate
    logistic regression, Mann-Whitney u-test
    
    Covariates: Smoking. Vitamin C,
    polymorphisms of XPD repair gene in
    exon 23 and 6 and GSTM 1 and
    XRCC1 genes
    
    Season: Winter
    Pollutant: PM,0
    
    Range (Min, Max): 32-55
    
    Monitoring Stations: 2 (and personal
    monitors)
    No relationship between short term
    exposure to C-PAHs evaluated by
    personal monitors and DMA adduct
    level. Genetic damage was observed in
    city policemen working in winter
    outdoors in the Prague downtown area
    
    they had slightly elevated aromatic DMA
    adduct levels, which was statistically
    significant for a distinct DMA adduct
    spot that could originate from ambient
    exposure to B[a]P
    
    Total PAH-DNA adducts: p = 0.065
    
    Exposed: 0.92 ± 0.28 adducts/108
    nucleotids
    
    Control: 0.82 ±0.23 adducts/108
    nucleotids
    
    B[o]P-like adducts:
    
    Exposed: 0.122 ± 0.36 adducts/108
    nucleotids
    
    Control: 0.099 ± 0.035 adducts/108
    nucleotids
    
    Multiple regression "like" B[a]P-DNA
    adduct for air pollution exposure group:
    6 = 0.016, p  = 0.01
    December 2009
                                  E-434
    

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                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: (Liu et al, 2009,1902921
    Period of Study: 1995-2005
    Location: Taiwan
    Outcome: Bladder Cancer Mortality
    (ICD-9 188)
    Age Groups: 50-69
    Study Design: Case-crossover
    Statistical Analysis: Multiple Logistic
    Regression
    Statistical Package: NR
    Covariates: none
    Dose-response Investigated? No
    Pollutant: PM,0
    Averaging Time: Annual mean of 24-h
    avg
    Tertiles (median):
    T1:<52.80
    72:53.04-71.72
    T3: 72.24-90.29
    Copollutant: 03, CO, N02, S02
    Copollutant (correlation): NR
    Monitoring Sattions: 64
    Increment:
    Odds Ratio (M in Cl, Max Cl)
    Lag
    T1vs. 71:1.00 (ref)
    T2 vs. 71:1.08 (0.83-1.41)
    T3 vs. 71:1.39(1.06-1.83)
    P for trend = .020
    Reference: (Pope et al., 2002, 0246891
    Period of Study: 1982-1998
    Location: 50 U.S. states, District of
    Columbia, and Puerto Rico
    Outcome (ICD9): Lung cancer mortality
    (162)
    Age Groups: Ages >30 yr Study
    Design: Longitudinal cohort (Cancer
    Prevention Study II)
    N: 1.2 million people
    Statistical Analyses: Cox proportional
    hazard, generalized additive
    Covariates: Age, sex,  race, education,
    smoking status, marital status,
    occupational exposure, diet, body-mass
    index, alcohol consumption
    Pollutant: PM,0
    Mean (SD): 1982-1998: 28.8(5.9)
    Effect estimates: Effect estimates were
    recorded in Fig 5 and not presented
    quantitatively anywhere else
    Reference: Sram et al, (2007, 1884571
    Period of Study: Jan and Mar of 2004
    Location: Prague, Czech Republic
    Outcome: Chromosomal aberrations
    Study Design: Panel
    Covariates: Urinary cotinine, plasma
    levels of vitamins A, E and C, folate,
    total cholesterol, HDL and LDL
    cholesterols, and triglycerides
    Statistical Analysis: Bivariate
    correlations, ANOVA, Mann-Whitney,
    Kruskal-Wallis and Spearman rank
    correlation
    Statistical Package: S7A7IS7ICA
    Age Groups: 61 city policemen, aged
    34 + 8 yr,  spending 8+  h outdoors
    Pollutant: PM,0
    Averaging Time: NR
    Mean (SD) Unit:
    Jan: 55.6 pg/m3
    Mar: 36.4 pg/m3
    Copollutant: PM25
    Results not given by PM increment.
    Reference: Sram et al, (2007, 1884571
    Period of Study: Jan and Mar of 2004
    Location: Prague, Czech Republic
    Outcome: Chromosomal aberrations
    Study Design: Panel
    Covariates: Urinary cotinine, plasma
    levels of vitamins A, E and C, folate,
    total cholesterol, HDL and LDL
    cholesterols, and triglycerides
    Statistical Analysis: Bivariate
    correlations, ANOVA, Mann-Whitney,
    Kruskal-Wallis and Spearman rank
    correlation
    Statistical Package: S7A7IS7ICA
    Age Groups: 61 city policemen, aged
    34 + 8 yr,  spending 8+  h outdoors
    Pollutant: PM25
    Averaging Time: NR
    Mean (SD) Unit:
    Jan: 44.4 pg/m3
    Mar: 24.8 pg/m3
    Copollutant: PM,0
    Results not given by PM increment.
    December 2009
                                    E-435
    

    -------
                 Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: (Tarantini et al., 2009,
    192010)Period of Study: NR
    Location: Brescia, Italy
    Outcome: DMA methylation content
    estimated byAlu, LINE-1 and iNOS
    analysis
    Study Design: Panel
    Covariates: age, BMI, smoking,
    number of cigarettes/day
    Statistical Analysis: Mixed effects
    models
    Statistical Package: NR
    Age Groups: 63 male workers between
    27 and 55 yr, mean age 44.
    Pollutant: PM,0
    Averaging Time: NR
    Mean (SD) Unit: NR
    Individual Exposure Range: 73.4-
    1220|jg/m3
    Copollutant (correlation): NR
    Difference in DMA Methylation before
    and after work exposure, mean (SE)
    Alu (%5mC): 0.00 (0.08), p = 0.99
    LINE-1 (%5mC): 0.02 (0.11), p = 0.89
    iNOS (%5mC): -0.61 (0.26), p = 0.02
    Reference: (Vineis et al, 2006,
    1920891
    
    Period of Study: 1990-1999
    Location: 10 European countries
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Reference: (V\fei et al, 2009, 1923611
    Period of Study: Nov 2006-Jan 2007
    Location: Peking, China
    
    
    
    Outcome: Lung cancer
    
    Study Design: Nested case-control
    Covariates: Age, sex, country, smoking
    status, time since recruitment,
    education, BMI, physical activity, intake
    of fruit, vegetables, meat, alcohol and
    energy
    Statistical Analysis: Conditional
    logistic regression models
    
    Statistical Package: NR
    
    Age Groups: 35-74 at recruitment
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Urinary 8-OHdG increase
    Study Design: Panel
    Covariates: NR
    
    Statistical Analysis: Analysis of
    variance model with autoregressive
    terms
    Pollutant: PM,0
    
    Averaging Time: NR
    Mean by Country (ug/m3):
    France
    lle-de-France
    1990-1994:22.3
    1995-1999: 19.9
    Northeast France
    1990-1994:30.2
    1995-1999:29.5
    Italy
    Turin
    1990-1 994' 73 4
    1995-1999:61.1
    Florence
    1990-1994:40.4
    1995-1999:33.3
    United Kingdom
    Oxford
    1990-1994:29.0
    1995-1999:25.5
    Cambridge
    1990-1994: NR
    1995-1999:25.4
    The Netherlands
    Utrecht
    1990-1994:42.8
    1995-1999:40.0
    Bilthoven
    1990-1994:39.0
    1995-1999:37.2
    Germany
    Heidelberg
    1990-1994: NR
    1995-1999:27.0
    Potsdam
    1990-1994:32.0
    1995-1999:28.9
    Range (Min, Max): NR
    Copollutant: N02, 03, S02
    Pollutant: PM25
    Averaging Time: 24 h
    Median: 154. 87 pg/m3
    
    IQR: 166.29
    Copollutant (correlation): NA
    Increment: 10|jg/m3
    
    Odds Ratios (Min Cl, Max Cl) for
    increase in lung cancer per
    increment increase in PM-:
    0.91 (0.70-1.18)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Increment: 1 66.29 pg/m3
    8-OHdG Concentrations, pre and
    post-work shift, subjects avgd
    Pre-work: 1.83
    
    Post-work: 6.92
                                      Statistical Package: SAS
                                      Age Groups: Two nonsmoking security
                                      guards, ages 18 and 20
                                                                         Concentration Changes (96%CI) of 8-
                                                                         OHdG per IQR Increase
                                                                         Pre-work: 0.256 (0.040, 0.472), p =
                                                                         0.021
                                                                         Post-work: 2.370 (0.907, 3.833), p =
                                                                         0.002
    All units expressed in pg/m unless otherwise specified.
    December 2009
                                   E-436
    

    -------
    Table E-27.    Long-term exposure - cancer outcomes - PIVhs (including PM components/sources).
                  Study
           Design & Methods
            Concentrations1
                                          Effect Estimates (95% Cl)
    Reference: Baccarelli et al, (2009,
    1881831
    Outcome: DMA methylation of LINE-1
    andAlu
    Period of Study: Jan 1999-Jun 2007    Study Design: Panel
    Location: Boston, Massachusetts
    Covariates: age, BMI, smoking status,
    pack-yr, statin use, fasting blood
    glucose, diabetes mellitus, percent
    lymphocytes and neutrophils in
    differential blood count, day of the
    week, season, temperature
    
    Statistical Analysis: Mixed effects
    models
    
    Statistical Package: SAS
    
    Age Groups: 719 elderly individuals,
    mean age 73.3, range 55-100 yr
    Pollutant: PM25
    
    Averaging Time: NR
    Mean (SD) Unit:
    4h: 12.2 (7.7) pg/m3
    1 day: 10.9 (6.3) pg/m3
    2 day: 10.6 (5.2  pg/m3
    3 day: 10.4(4.8  pg/m3
    4day:10.3(4.3)|jg/m3
    ZA- ^n 0 Q Q I in/r^
                                       Increment: SD for each lag
    
                                       Correlation Coefficient (96% Cl)
    
                                       Lag for LINE-1 Methylation
                                       4h: -0.07 (-0.13, -0.01), p = 0.03
                                       1 day: -0.09 (-0.16, -0.02), p = 0.008
                                       2 day: -0.10 (-0.17, -0.03), p = 0.003
                                                                                      pg/m3
                                                                                                             3 day:-0.10
                                                                                                             4 day:-0.10
                                                  -0.17, -0.04), p = 0.003
                                                  -0.16, -0.03), p = 0.004
                                                                          7d: 10.3 (3.3) pg/m3
                                                                          Copollutants: Black carbon, Sulfate
                                       5d: -0.10 (-0.16, -0.03), p = 0.004
                                       6d:-0.11 (-0.17, -0.04), p = 0.001
                                       7d:-0.13 (-0.19,-0.06), p< 0.001
                                       Correlation Coefficient (96% Cl)
    
                                       Lag for Alu Methylation
                                       4h: 0.03 (-0.03, 0.09), p = 0.28
                                       1 day: -0.01 (-0.07, 0.05), p = 0.74
                                                                                                             2 day: -0.01
                                                                                                             3 day:-0.01
                                                                                     -0.07, 0.05), p = 0.82
                                                                                     -0.07, 0.05), p = 0.78
                                                                                                             4 day: -0.01 (-0.07, 0.05), p = 0.75
                                                                                                             5d:-0.01
                                                                                                             6d:-0.01
                                                                                   -0.07, 0.05
                                                                                   -0.07, 0.05
                                                         , p = 0.84
                                                         , p = 0.74
                                                                                                             7d: -0.01 (-0.07, 0.05), p = 0.71
                                                                                                             Correlation Coefficient (96% Cl)
    
                                                                                                             LINE-1 Methylation and ma of
                                                                                                             pollutant levels
                                                                                                             4h: -0.04 (-0.11, 0.03), p = 0.24
                                                                                                             7d: -0.11 (-0.18, -0.05), p = 0.001
    Reference: Binkova et al. (2007,
    1562731
    Period of Study: Feb 2001
    
    Location: Prague, Czech Republic
    Outcome: Bulky aromatic PAH-DNA
    adducts
    
    Age Groups: 22-50 yr
    
    Study Design: Case Control
    
    N: 53 exposed policemen and 52
    control  policemen
    
    Statistical Analyses: Multivariate
    logistic regression,  Mann-Whitney,
    Rank-Sum U-test
    
    Covariates: Smoking. Vitamin C,
    polymorphisms of XPD repair gene in
    exon 23 and 6 and  GSTM 1 gene
    
    Season: Winter
    Pollutant: PM25
    
    Range (Min, Max): 27-38
    
    c-PAHs: range = 18-22 ng/m3
    
    B[a]P: range = 2.5-3.1 ng/m3
    
    Monitoring Stations: 2
                                       Genetic damage was observed in city
                                       policemen working in winter outdoors in
                                       the Prague downtown area
    
                                       They had slightly elevated aromatic
                                       DMA adduct levels, which was more
                                       pronounced for a distinct DMA adduct
                                       spot that could originate from ambient
                                       exposure to B[a]P
                                       Total DNA-adduct level
                                       Exposed: 0.92+0.28  adducts/108
                                       nucleotides
                                       Control: 0.82+0.23 adducts/108
                                       nucleotides
                                       p = 0.065
                                       "Like" B[a]P-derived DNA adducts
                                       Ex posed: 0.122+0.036
                                       Control: 0.101+0.035
                                       p < 0.01
                                       Multiple Regression (exposed vs.
                                       control)
                                       B = 0.016,  p = 0.011	
    December 2009
                                   E-437
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Brunekreef et al, (2009,
    1919471
    
    Period of Study: 1987-1996
    
    Location: The Netherlands
    Outcome: Air pollution related lung
    cancer deaths (ICD-9 162)
    
    Study Design: Case-cohort
    
    Covariates
    
    Individual: Sex, age, Quetelet index,
    smoking status, passive smoking
    status, educational level, occupation,
    occupational exposure, marital status,
    alcohol use, intake of vegetables, fruits,
    energy, saturatured and
    monounsaturated fatty acids, trans fatty
    acids, total fiver, folic acid and fish
    
    Area-level: Percent of population with
    income below the 40th percentile and
    above the 80th percentile
    
    Statistical Analysis: Cox proportional
    hazards
    
    Statistical Package: State, SPSS, R
    
    Age Groups: 120,000 adults aged 55-
    69 yr at enrollment
    Pollutant: PM25, estimated from PM10
    levelsf
    
    Averaging Time: 24 h
    
    60th Percentile: 28 pg/m3
    
    Range (Min, Max): 23-37
    
    Copollutant (correlation):
    
    N02: 0.75
    
    Black Smoke: 0.84
    
    NO: 0.69
    
    SO,: 0.43
    Increment: 10|jg/m
    
    Relative Risk (96% Cl) for
    associations between PM25 and lung
    cancer incidence
    
    Case Cohort
    
    Unadjusted: 0.93 (0.71-1.22)
    
    Adjusted: 0.67 (0.41-1.10)
    
    Unadjusted Complete: 0.87 (0.60-1.25)
    
    Full Cohort
    
    Unadjusted: 0.96 (0.79-1.18)
    
    Adjusted: 0.81 (0.63-1.04)
    
    Unadjusted Complete: 0.92 (0.74-1.15)
    Reference: Liu et al. (2008,1567081
    
    Period of Study: 1995-2005
    
    Location: Taiwan
    Outcome: Brain cancer deaths
    
    ICD9:191
    
    Age Groups: 29 yr of age or younger
    
    Study Design: Matched case-control
    by sex, yr of birth and death
    
    N: 340 matched pairs
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Age, gender, urbanization
    level of residence, nonpetrochemical air
    pollution exposure level
    No direct measures of pollutants
    
    used an index to assign petrochemical
    air pollution exposure (each municipality
    was assigned an exposure by dividing
    the number of workers per municipality
    employed in the petrochemical industry
    by the municipalities total population).
    Study participants divided into tertiles
    based on this index.
    People who lived in the group of
    municipalities with the highest levels of
    air pollutants arising from petrochemical
    sources were at a statistically significant
    increased risk for brain cancer
    development compared to the group
    living in municipalities with the lowest
    petrochemical air pollution exposure
    index.
    Effect Measure: OR (95%CI)
    Tertile1:1.?0
    Tertile 2:1.54 (0.98-2.42)
    Tertile 3:1.65 (1.00-2.73)
    P for trend <0.01
    Reference: Nafstad et al. (2004,
    0879491
    Period of Study: 1972-1998
    
    Location: Oslo, Norway
    Outcome: Lung cancer
    
    ICD7 162.1-162.9
    
    Age Groups: 40-49 yr old men
    
    Study Design: Cohort
    
    N: 16,209 males
    
    Statistical Analyses: Cox regression
    models (proportional hazards)
    
    Covariates: Age at inclusion, smoking
    habits, education
    
    Season: all yr
    PM values had small variations in
    exposure level, and strong correlations
    with another pollutant of interest (S02)
    and were not considered in analyses.
    
    Co pollutants:
    S02
    
    NOX
                                                                                                                  No effect estimates for PM
    Reference: (Pope and Burnett, 2007,
    0909281
    Period of Study: 1982-1998
    
    Location: 50 U.S. states, District of
    Columbia, and Puerto Rico
    Outcome: Lung cancer mortality (162)
    
    Age Groups: >30 yr
    
    Study Design: Longitudinal cohort
    (Cancer Prevention II Study)
    
    N: 415,000 CPS 11 patients with
    information involving PM10
    
    Statistical Analyses: Cox proportional
    hazard, incorporating a spatial random-
    effects component
    
    Covariates: Age, sex, race, education,
    ETS, smoking status, marital status,
    occupational exposure, diet, body-mass
    index, alcohol consumption
    Pollutant: PM25
    
    Mean (SD): 1979-1983: 21.1(4.6)
    
    1999-2000:14.0(3.0)
    
    Avg: 17.7(3.7)
    
    Averaging time: 1982-1998
    PM Increment: 10 pg/m
    
    RR Estimate [Lower Cl, Upper Cl]
    Lung Cancer: 1979-1983:1.08[1.01,
    1.16]
    
    1999-2000:1.13[1.04, 1.22]
    
    Avg:1.14[1.04,1.23]
    
    RR results were also presented in Fig
    2-5. Authors found that PM25 had the
    strongest association with increased
    risk of all-cause, cardiopulmonary, and
    lung cancer mortality.
    December 2009
                                     E-438
    

    -------
                  Study
                                              Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Sram et al, (2007, 1884571  Outcome: Chromosomal aberrations
    Period of Study: Feb 2001            Study Design: Panel
    Location: Prague, Czech Republic
                                       Covariates: Urinary cotinine, plasma
                                       levels of vitamins A, E and C
                                       Statistical Analysis: Bivariate
                                       correlations, ANOVA, Mann-Whitney,
                                       Kruskal-Wallis and Spearman rank
                                       correlation
                                       Statistical Package: STATISTICA,
                                       SAS
                                       Age Groups: 53 city policemen, aged
                                       22-50 yr, spending 8+ h outdoors
    Pollutant: PM,0
    Averaging Time: NR
    Range: 32-55|jg/m3
    Copollutant: PM25
                                                                                                             Results not given by PM increment.
    Reference: Sram et al, (2007, 1884571  Outcome: Chromosomal aberrations
    Period of Study: Feb 2001            Study Design: Panel
    Location: Prague, Czech Republic
                                       Covariates: Urinary cotinine, plasma
                                       levels of vitamins A, E and C
                                       Statistical Analysis: Bivariate
                                       correlations, ANOVA, Mann-Whitney,
                                       Kruskal-Wallis and Spearman rank
                                       correlation
                                       Statistical Package: STATISTICA,
                                       SAS
                                       Age Groups: 53 city policemen, aged
                                       22-50 yr, spending 8+ h outdoors
    Pollutant: PM25
    Averaging Time: NR
    Range: 27-38|jg/m3
    Copollutant: PM,0
                                                                                                             Results not given by PM increment.
    Reference: Tovalin et al. (Tovalin et al.,  Outcome: DMA damage (comet tail
    	                       length)
    2006, 091322'
    Period of Study: Apr-May 2002
    Location: Mexico City and Puebla
                                       Age Groups: 18-60
                                       Study Design: Panel Study
                                       N: 55 male workers
                                       Statistical Analyses: Mann-Whitney
                                       test, Chi-square, Spearman's
                                       correlation, logistic regression
                                       Statistical Package: SPSS and STATA
    Pollutant: PM25
    Personal monitoring values observed in
    this study reported in Tovalin et al. 2003
    Median Personal Exposure to PM;::
    Mexico City
    Outdoor Worker: 133|jg/m3
    Indoor Worker: 86.6 pg/m3
    Puebla
    Outdoor Worker: 122 pg/m3
    Indoor Worker: 78.3 pg/m3
    OR for being a highly damaged worker:
    1.02(1.01-1.04), p = 0.03
    Correlation between comet tail length
    and PM 2.5: 0.57, p = 0.000
    OR for being a highly damaged worker:
    1.03, p< 0.07
    Comet Tail Length
    Outdoor Worker: 46.80 pm
    Indoor Worker: 30.11 pm
    p<0.01
    Percent Highly DMA Damaged Cells
    Outdoor Worker: 68%
    Indoor Worker: 20%
    All units expressed in pg/m unless otherwise specified.
    December 2009
                                                                      E-439
    

    -------
    Table E-28.    Long-term exposure - cancer outcomes - other PM size fractions.
                 Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: (Pope et al., 2002, 0246891  Outcome: Lung cancer mortality (162)
    
    Period of Study: 1982-1998
    Location: 50 U.S. states, District of
    Columbia, and Puerto Rico
    Age Groups: Ages >30 yr who were
    members of a household with at least 1
    individual >45yrs.
    
    Study Design: Longitudinal cohort
    (Cancer Prevention Study II)
    
    N: 359,000 CPS II participants with
    information regarding PM15 and
    PM15-PM25
    
    Statistical Analyses: Cox proportional
    hazard, incorporating a spatial random-
    effects component
    
    Covariates: Age, sex, race, education,
    ETS, smoking status, marital status,
    occupational exposure, diet, body-mass
    index, alcohol consumption
    
    Smoking covariates adjusted for:
    
    Indicator: current smoker, former
    smoker, pipe or cigar smoker, started
    smoking before or after age 18
    
    Continuous, current and former
    smokers: yr smoked, yr smoked
    squared, cigarettes per day, cigarettes
    per day squared, number of h per day
    exposed to passive cigarette smoke.
    Pollutant: PM,5
    
    Mean (SD): 1979-1983: 40.3(7.7)
    
    Pollutant: PM15-2.5
    
    Mean (SD): 1979-1983:19.2(6.1)
    
    Averaging Time: 1979-1983
    Relative risks effect estimates were
    recorded in Fig 5 and not presented
    quantitatively anywhere else.
     All units expressed in pg/m  unless otherwise specified.
    December 2009
                                   E-440
    

    -------
    E.7. Long-Term  Exposure  and  Reproductive  Effects
    Table E-29.    Long-term exposure - reproductive outcomes - PMio.
                Study
          Design & Methods
           Concentrations
       Effect Estimates (95% Cl)
    Reference: Bell at al. (2007, 0910591
    Period of Study: 1999-2002
    Location: Connecticut-Fairfield,
    Hartford, New Haven, New London,
    Windham, Massachusetts-Barnstable,
    Berkshire, Bristol, Essex, Hampden,
    Middlesex, Norfolk, Plymouth, Suffolk,
    Worcester
    Outcome: Low birth weight
    Age Groups: Neonates
    Study Design: Cross-sectional
    N: 358,504 births
    Statistical Analyses: Multiple logistic
    and linear regressions
    Covariates: Child's sex, mother's
    education, tobacco use, mother's
    marital status,  mother's race, time
    prenatal care began, mother's age, birth
    order, gestation length
    Dose-response Investigated? No
    Statistical Package: NR
    Pollutant: PM10
    Averaging Time: 24 h
    Mean (SD): 22.3 (5.3)
    Monitoring Stations: NR
    Copollutant: N02, CO, S02
    Gestation exposure correlation:
    PM25:r = 0.77
    NO,: r = 0.55
    PM Increment: 7.4 pg/rri (IQR)
    Difference in birth weight [Lower Cl,
    Upper Cl]
    per IQR for the gestational period:
    -8.2 [-11.1to-5.3]
    Difference in birth weight by race of
    mother [Lower Cl, Upper Cl]:
    Black:-7.9 [-16.0, 0.2]
    White:-9.0 [-12.2 to-5.9]
    Range among trimester models for
    change in birth weight per IQR
    increase (min, max)
    trimester: -6.6 to -4.7
    3rd
    OR Estimate for birth weight <2600 g
    [Lower Cl, Upper  Cl]
    per IQR for the gestational period:
    1.027 [0.991, 1.064]
    Notes: Analyses using first births alone
    yielded similar results. Two pollutant
    models for uncorrelated pollutants were
    analyzed  but not presented
    quantitatively.
    Reference: Brauer et al. (2008,
    1562921
    Period of Study: 1999-2002
    Location: Vancouver, BC
    Outcome: Preterm birth, SGA, LBW
    Age Groups: Study Design: Cross-
    sectional
    N: 70,249 births
    Statistical Analyses: Logistic
    regression
    Covariates: Sex, parity, month and yr
    of birth, maternal age and smoking,
    neighborhood level income and
    education
    Statistical Package: SAS
    Pollutant: PM,0
    Averaging Time: 24-h
    Mean (SD): 12.7
    Range (Min, Max): 5.6, 35.4
    Monitoring Stations: 19
    Copollutant:
    NO
    N02
    CO
    S02
    03
    PM Increment: 1 pg/m
    Effect Estimate [Lower Cl, Upper Cl]
    pollutant assessed for entire
    pregnancy period:
    SGA: 1.02 (0.99,  1.05)
    LBW: 1.01 (0.95,  1.08)
    Preterm (<30wk): 1.13 (0.95,1.35)
    December 2009
                                E-441
    

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                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Chen et al. (2002, 0249451
    
    Period of Study: 1991-1999
    
    Location: Washoe County, Nevada
    Outcome: Birth weight
    
    Age Groups: Sngle births with
    gestationai age between 37-44 wk and
    maternal all ages
    
    Study Design: Cross-sectional
    
    N: 33,859 single births
    
    Statistical Analyses: multiple linear
    and logistic regression
    
    Covariates: infant sex, maternal
    residential city, education, medical risk
    factors, active tobacco use,  drug use,
    alcohol use, prenatal care, mother's
    age, race and ethnicity of mothers and
    weight gain of mothers
    
    Dose-response Investigated? No
    
    Statistical Package: SPSS 10.0
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 31.53 (22.32)
    
    Percentiles: 26th: 16.80
    
    60th(Median): 26.30
    
    76th: 39.35
    
    Range (Min, Max): (0.97-157.32)
    
    Monitoring Stations: 4
    
    Copollutant: CO
    
    03
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Using continuous pollutant variables
    Model 1-PM10
    1 trimester
    Crude model: IS = -0.186 (0.225)
    Adjusted model: IS = -0.082 (0.221)
    2 trimester
    Crude model: 6 = 0.045(0.223)
    Adjusted model: IS = -0.020 (0.221)
    3 trimester
    Crude model: IS = -0.509 (0.231)
    Adjusted model: IS = -0.395 (0.227)
    Whole
    Crude model: IS = -0.823 (0.459)
    Adjusted model: IS = -0.726 (0.483)
    Model 2
    COandPMio
    3 trimester
    Crude model: IS = -1.044 (0.457)
    Adjusted model: IS = -1.078 (0.445)
    03andPM10
    3 trimester
    Crude model: IS = -1.035 (0.385)
    Adjusted model: IS = -0.966 (0.378)
    Model 3
    PMio, 03, and CO
    3 trimester
    Crude model: IS = -1.070 (0.458)
    Adjusted model: IS = -1.102 (0.446)
    Whole
    Crude model: IS = -1.413 (0.733)
    Adjusted model: IS = -1.332 (0.738)
    Using categorical pollutant variables-3
    trimester
    Model 1-PM10
    Adjusted model: IS = -10.243 (5.235)
    Model 2
    PM,o and CO
    Adjusted model: IS = -11.883 (6.108)
    PMio and 03 Adjusted model:
    IS = -9.144 (5.860)
    Model 3
    PM10, CO, and 03 Adjusted model:
    IS = -10.937 (6.222)
    Using logistic regression
    (ref value = <19.72 pg/m3
    Exposure to PM10 at 3 trimester at
    >44.74 pg/m3: OR =
    1.105(0.714-1.709)
    
    Between 19.72-44.74 pg/m3:
    OR = 1.050 (0.811-1.360)
    
    Notes: Crude model: model with air-
    pollutant variables controlled with
    gestationai age only. Adjusted model:
    model with air-pollutant variables
    controlled with confounding variables
    including gestationai age, infant sex,
    maternal residential city, education,
    medical risk factors, active tobacco use,
    drug use, alcohol use, the trimester
    begins  prenatal visits, total prenatal
    visits, mother's age, race and ethnicity
    of mother, and weight gain of mother.
    December 2009
                                     E-442
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Dales et al. (2004, 0873421  Outcome: SIDS (a sudden,
    „  •  .  ,~   ,   ,   ^n^ r»   -.000   unexplained death of a child <1 yr of
    Period of Study: Jan 1984-Dec 1999       -   	  ••
    Location: Canada (12 cities)
    age for which a clinical investigation
    and autopsy fail to reveal a cause of
    death)
    
    Age Groups: Infants <1 yr
    
    Study Design: Time-series
    
    N: Total population of 12 cities:
    10,310,309
    
    1556 cases of SIDS over study period
    
    Statistical Analyses: Random-effects
    regression model for count data (a
    linear association between air pollution
    and the incidence of SIDS was
    assumed on the logarithmic scale)
    
    Covariates: Weather factors (daily
    mean temp, daily mean relative
    humidity, maximum change in
    barometric pressure, all measured on
    the day of death), length of time-period
    adjustment, seasonal indicator
    variables, and size-fractionated PM
    
    Season: Used piece-wise constant
    functions in time that varied by 3, 6, or
    12 mo
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Pollutant: PM,0
    
    Averaging Time: 24-hs (PM measures
    every 6 days
    
    gaseous pollutants every day)
    
    Mean (IQR): PM10: 23.43 (15.56)
    
    Range (Min, Max): IQR presented
    above
    
    Monitoring Stations: When data were
    available from more than 1 monitoring
    site, they were avgd
    
    Copollutant:
    
    PM25
    
    PM10
    
    CO
    
    N02
    
    03
    
    SO,
    Notes: The abstract reports no
    association between increased daily
    rates of SIDS and fine particles
    measured every sixth day. However, no
    effect estimates presented for PM (only
    gaseous pollutants adjusted for PM).
    December 2009
                                    E-443
    

    -------
                   Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Dugandzic et al. (2006,
    0886811
    
    Period of Study: Jan 1988-Dec 2000
    
    Location: Nova Scotia,  Canada
    Outcome: Low birth weight (LBW)
    (<2500 grams)
    
    Age Groups: Babies born 2 37 wk (full
    term)
    
    Study Design: Cross-sectional
    
    N: 74,284 births
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Maternal age, parity,  prior
    fetal death,  prior neonatal death, prior
    low birth weight infant, smoking during
    pregnancy,  neighborhood family
    income, infant gender, gestational age,
    weight change, yr of birth
    
    Season: All
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: 24-h
    
    Mean (SD):
    
    Percentiles:26th:14
    
    60th(Median): 16
    
    76th: 19
    
    Range (Min, Max): Max: 53
    
    Monitoring Stations: 18
    
    Copollutant: S02, 03
    
    Notes: Only 3 stations monitored more
    than 1 pollutant. Daily data were
    available for gaseous pollutants while
    particulate levels were  measured every
    sixth day.
    PM Increment:
    1) IQR (5 pg/m3)
    2) Quartiles (first quartile is the
    reference)
    Exposure period: first trimester
    Unadjusted model
    2nd quartile: 1.24 (0.95,1.62)
    3rd quartile: 1.25 (0.96,1.62)
    4th quartile: 1.28 (1.00,1.65)
    Per IQR: 1.09 (1.00,1.18)
    Adjusted model
    2nd quartile: 1.24 (0.94,1.64)
    3rd quartile: 1.24 (0.95,1.64)
    4th quartile: 1.33 (1.02,1.74)
    Per IQR: 1.09 (1.00,1.19)
    Adjusted for Birth Year model
    2nd quartile: 1.14 (0.86,1.52)
    3rd quartile: 1.08 (0.82,1.44)
    4th quartile: 1.11 (0.84,1.48)
    Per IQR: 1.03 (0.94,1.14)
    Exposure period: second trimester
    Unadjusted model
    2nd quartile: 0.98 (0.76,1.28)
    3rd quartile: 1.09 (0.84,1.40)
    4th quartile: 1.00 (0.77,1.28)
    Per IQR: 1.00 (0.91,1.09)
    Adjusted model
    2nd quartile: 1.02 (0.77,1.34)
    3rd quartile: 1.16 (0.89,1.51)
    4th quartile: 1.09 (0.83,1.42)
    Per IQR: 1.02 (0.93,1.12)
    Adjusted for Birth Year model
    2nd quartile: 0.99 (0.75,1.31)
    3rd quartile: 1.10(0.84,1.45)
    4th quartile: 1.01 (0.76,1.34)
    Per IQR: 1.00 (0.90,1.10)
    Exposure period: third trimester
    Unadjusted model
    2nd quartile: 0.93 (0.72,1.20)
    3rd quartile: 1.07 (0.83,1.37)
    4th quartile: 0.92 (0.71,1.18)
    Per IQR: 0.95 (0.87, 1.05)
    Adjusted model
    2nd quartile: 0.96 (0.73,1.26)
    3rd quartile: 1.14 (0.88,1.48)
    4th quartile: 1.03 (0.79,1.35)
    Per IQR: 0.99 (0.89, 1.09)
    Adjusted for Birth Year model
    2nd quartile: 0.92 (0.70,1.21)
    3rd quartile: 1.04 (0.80,1.36)
    4th quartile: 0.92 (0.69,1.22)
    Per IQR: 0.94 (0.85, 1.05)	
    Reference: Gilboa, et al. (2005,
    0878921
    Period of Study: Jan 1996-Dec 2000
    
    Location: Seven Counties in Texas,
    USA: (Bexar, Dallas, El Paso, Harris,
    Hidalgo, Tarrant, Travis)
    Outcome: Birth defects
    
    Age Groups: Newborn babies
    
    Study Design: Case-control
    
    N: 5,338 newborn babies
    
    4574 controls
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Alcohol consumption
    during pregnancy, attendant of delivery
    (i.e., the person who delivered the baby
    (physician/nursemaid-wife vs. other)),
    gravidity, marital status, maternal age,
    maternal education, maternal illness,
    maternal race/ethnicity, parity, place of
    delivery, plurality, prenatal care, season
    of conception, and tobacco use during
    pregnancy
    
    Control frequency matched to cases by
    vital status, yr and maternal county of
    Pollutant: PM10
    
    Averaging Time: NR
    
    Percentiles:26th:<19.5
    
    50th(Median): 19.5-<23.8
    
    76th: 23.8-<29.0
    
    100th: > 29.0
    
    Monitoring Stations: The
    Environmental Protection Agency
    provided raw data or hourly (for gases)
    or daily (for PM) air pollution
    concentrations for the seven study
    counties
    
    Copollutant:  CO, N02,03, S02
    PM Increment: calculated as quartiles
    of avg concentration during wk3-8 of
    pregnancy
    
    Isolated Cardiac Defects
    Aortic artery and valve defects:
    25th: 0.40 (0.15, 1.03)
    50th: 0.45 (0.18, 1.13)
    75th: 0.68 (0.28, 1.65)
    Atrial Sepal defects:
    25th: 1.41 (0.86, 2.31)
                                                                                                                    50th: 2.13
                                                                                                                    75th: 2.27
              1.34,3.37
              1.43,3.60
                                                                                                                    Pulmonary artery and valve defects:
                                                                                                                    25th: 1.14
                                                                                                                    50th: 0.79
              0.62,2.10
              0.41, 1.55
                                                                                                                    75th: 0.68 (0.33, 1.40)
                                                                                                                    Ventricular Sepal defects:
                                                                                                                    25th: 0.83 (0.61, 1.11)
                                                                                                                    50th: 1.12 (0.85, 1.48)
                                                                                                                    75th: 0.98 (0.73, 1.32)
                                                                                                                    Multiple Cardiac Defects
                                                                                                                    Conotruncal defects:
                                                                                                                    25th: 1.13  0.79, 1.62
                                                                                                                    50th: 1.20  0.84,1.72
    December 2009
                                     E-444
    

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                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                         residence
    
                                         Season: Covariate in model
    
                                         Dose-response Investigated? Yes
    
                                         Statistical Package: SASv 8.2
                                                                       75th: 1.26 (0.86, 1.84)
                                                                       Endocardial cushion and mitral valve
                                                                       defects:
                                                                       25th: 0.82 (0.54, 1.25)
                                                                       50th: 0.66
                                                                       75th: 0.63
                                           0.42, 1.05
                                           0.38, 1.03
                                                                                                                   Isolated Oral Clefts
                                                                                                                   Cleft lip with or without palate:
                                                                                                                   25th: 1.29 (0.90, 1.85)
                                                                                                                   50th: 1.45 (1.01, 2.07)
                                                                                                                   75th: 1.37 (0.94,2.00)
                                                                                                                   Cleft palate:
                                                                                                                   25th: 0.99 (0.55, 1.78)
                                                                                                                   50th: 1.14 (0.64, 2.03)
                                                                                                                   75th: 1.11  (0.60, 2.06)
                                                                                                                   Individual Birth Defects
                                                                                                                   Aortic valve stenosis:
                                                                                                                   25th: 0.91  (0.53, 1.57)
                                                                                                                   50th: 0.86 (0.50, 1.50)
                                                                                                                   75th: 1.12 (0.63, 1.99)
                                                                                                                   Atrial Sepal defects:
                                                                                                                   25th: 1.10 (0.89, 1.35)
                                                                                                                   50th: 1.28
                                                                                                                   75th: 1.26
                                                                                 1.04, 1.57
                                                                                 1.03, 1.55
                                                                                                                   Coarctation of the aorta:
                                                                                                                   25th: 0.78
                                                                                                                   50th: 0.68
                                                                                 0.53, 1.15
                                                                                 0.45, 1.02
                                                                                                                   75th: 0.75 (0.48, 1.15)
                                                                                                                   Endocardial cushion defects:
                                                                                                                   25th: 0.87 (0.49, 1.55)
                                                                                                                   50th: 1.12 (0.64, 1.96)
                                                                                                                   75th: 0.89 (0.47, 1.65)
                                                                                                                   Ostium secundum:
                                                                                                                   25th: 1.15 (0.85, 1.55)
                                                                                                                   50th: 1.13
                                                                                                                   75th: 1.06
                                                                                 0.83, 1.53
                                                                                 0.77, 1.4
                                                                                                                   Pulmonary artery atresia without
                                                                                                                   ventricular Sepal defects:
                                                                                                                   25th: 1.93 (1.08, 3.45)
                                                                                                                   50th: 2.01 (1.11,3.64)
                                                                                                                   75th: 0.86 (0.41, 1.83)
                                                                                                                   Pulmonary valve stenosis:
                                                                                                                   25th: 1.16 (0.88, 1.55)
                                                                                                                   50th: 1.25
                                                                                                                   75th: 1.27
                                                                                 0.94, 1.66
                                                                                 0.94, 1.71
                                                                                                                   Tetralogy of Fallot:
                                                                                                                   25th: 1.21
                                                                                                                   50th: 1.40
                                                                                 0.72, 2.01
                                                                                 0.84, 2.33
                                                                                                                   75th:  1.450.85, 2.48)
                                                                                                                   Ventricular Sepal defects:
                                                                                                                   25th:  1.06 (0.90, 1.24)
                                                                                                                   50th:  1.10 (0.94, 1.29)
                                                                                                                   75th:  1.08 (0.92, 1.27)
    December 2009
                              E-445
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Gouveia et al. (2004,
    0556131
    
    Period of Study: 1997
    
    Location: Sao Paulo, Brazil
    Outcome: Birth weight
    
    Age Groups: Singleton full term live
    births within 1000 g to 5500 g
    
    Study Design: Cross sectional study
    
    N: 179,460 live births
    
    Statistical Analyses: GAM and
    Logistic regression models
    
    Covariates:  Maternal age, length of
    gestation, season, infant gender,
    maternal education, number of
    antenatal care visits,  parity, and the
    type of delivery
    
    Season: All seasons
    
    Dose-response Investigated? Yes
    
    Statistical Package: S-Plus 2000
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean (SD): 60.3 (25.2)
    
    Range (Mm, Max): (25.5-153.0)
    
    Monitoring Stations: maximum of 12
    sites
    
    Copollutant (correlation):
    C0:r = 0.9
    
    S02
    
    N02
    
    03
    PM Increment: 10 pg/m
    Mean [Lower Cl, Upper Cl]:
    Changes in birth weight (in g)
    First trimester = -13.7 (-27.0,-0.4)
    Second trimester = -4.4 (-18.9,10.1)
    Third trimester =14.6 (0.0, 29.2)
    RR Estimate [Lower Cl, Upper Cl]:
    (RR estimates are adjusted odds ratios
    for low birth weight according to
    quartiles of air pollution in each
    trimester of pregnancy.)
    Istquartile
    First trimester = 1 (REF)
    Second trimester = 1 (REF)
    Third trimester = 1 (REF)
    2nd quartile
    First trimester =1.105 (0.994,1.229)
    Second trimester = 1.003(0.904,1.113)
    Third trimester =1.004 (0.914,1.104)
    3rd quartile
    First trimester =1.049 (0.903,1.219)
    Second trimester = 1.074(0.920,1.254)
    Third trimester =1.003 (0.861,1.169)
    4th quartile
    First trimester =1.144 (0.878,1.491)
    Second trimester = 1.252 (1.028,1.525)
    Third trimester = 0.970 (0.780,1.205)
    Multiple linear regression coefficients
    (SE) obtained from single, dual, and
    three pollutant models
    Single pollutant model = -1.37 (0.68)
    Two pollutant (PM,0 and CO) = -0.51
    (0.87)
    Two pollutant (PM10 and S02) = -0.94
    (0.75)
    Three pollutant =  -0.47 (0.88)
    Reference: Ha et al. (2003, 0425521
    Period of Study: Jan 1995-Dec 1999
    
    Location: Seoul, South Korea
    
    
    
    
    Outcome: Post-neonate total and
    respiratory mortality
    Age Groups: 1 month-1 yr
    2 yr-65 yr, >65 yr
    Study Design: Time-series
    
    N: 1045 post-neonate deaths, 67,597 2-
    65 yr old deaths, 100,316 >65yr old
    deaths
    Pollutant: PM,0
    Averaging Time: 24 h
    
    Mean (SD): 69.2 (31. 6)
    Percentiles: 26th: 44.8
    
    SOth(Median): 64.2
    75th: 87.7
    Ranne/Min Mav\- 1 n -, I in/m ;
    PM Increment: 42.9 pg/m3
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Total Mortality:
    1 month-1 yr (post-neonates):
    1.142 [1.096, 1.190] lag 0
    2 yr-65 yr:
    1. 008 [1.006, 1.010] lag 0
    >65yr (elderly):
    1.023 [1.023, 1.024] lag 0
                                        Statistical Analyses: Generalized
                                        additive model
    
                                        Covariates: Seasonality, temperature,
                                        relative humidity, day of the week
    
                                        Dose-response Investigated? No
    
                                        Statistical Package: S Plus
    
                                        Lags Considered: 0,1,2,3,4,5,6,7,
                                        ma from 1-5 days
                                        245.4 pg/m3
    
                                        Monitoring Stations: 27
    
                                        Copollutant (correlation):
    
                                        N02:r = 0.73
    
                                        S02:r = 0.62
    
                                        03:r = -0.02
    
                                        CO: r = 0.63
                                        Respiratory Mortality:
                                        1 month-1 yr (post-neonates):
                                        2.018 [1.784, 2.283] lag 0
                                        2 yr-65 yr:
                                        1.066 [1.044, 1.090] lag 0
                                        >65yr (elderly):
                                        1.063 [1.055, 1.072] lag 0
    December 2009
                                     E-446
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Hansen, et al. (2006,
    0898181
    
    Period of Study: Jul 2000-Jun 2003
    
    Location: Brisbane, Australia
    Outcome: Pre-term birth (<37 wk)
    
    Age Groups: Newborn babies
    
    Study Design: Cross-sectional
    
    N: 1583 live pre-terms births
    
    28,200 singleton live births
    
    Statistical Analyses: Multiple logistic
    regression models
    
    Covariates: Neonate gender, mother's
    age, parity, indigenous status, number
    of antenatal visits, marital status,
    number of previous
    abortions/miscarriages, type of delivery,
    and index of SES
    
    Season: all
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS version 8.2
    Pollutant: PM,0
    
    Averaging Time: recorded hourly, avi
    daily
    
    Mean (SD): 19.6 (9.4)
    
    Range (Min, Max): 4.9,  171.7
    
    Monitoring Stations: 5
    
    Copollutant (correlation):
    Fine PM or bsp, 0.1 to <2.5 pg in
    diameter (0.58 to 0.76)
    
    03 (0.54 to 0.83)
    
    N02 (0.54  to 0.75)
    
    PM10 (0.80 to 0.93)
    
    Note: Correlations presented are for
    the individual pollutant across
    monitoring stations (not correlations
    between PM10 and the pollutant.)
    PM Increment: Trimester One
    
    4.5 pg/m3
    
    Last 90 days prior to birth
    
    5.7 pg/m3
    
    Odds Ratio [Lower Cl, Upper Cl]:
    
    Trimester 1
    
    1.15 [1.06,1.25]
    
    Last 90 days prior to birth
    
    1.04 [0.92,1.16]
    Reference: Hansen et al. (2007,
    0907031
    
    Period of Study: Jul 2000-Jun 2003
    
    Location: Brisbane, Australia
    Outcome: Birth weight and Small for
    Gestational Age (SGA
    
    <10th percentile for age and gender)
    
    Head circumference (HC) and crown-
    heel length (CHL) among subsample
    
    Study Design: Cross-sectional
    
    N: 26,617  births (birth weight analysis)
    and 21,432 (HC and CHL analyses)
    
    Statistical Analyses: Logistic (SGA)
    and linear  (birth weight, HC, CHL)
    regressions
    
    Covariates: Gender, gestational age
    (with a quadratic term), maternal age,
    parity, number of previous
    abortions/miscarriages, marital status,
    indigenous status,  number of antenatal
    visits, type of delivery, an index of SES,
    and season of birth
    
    Season: Assessed as a covariate
    
    Dose-response Investigated? Yes,
    assessed exposures as quartiles
    
    Statistical Package: SAS v8.2
    Pollutant: PM10
    
    Averaging Time: Trimester and
    monthly avg were used in analyses
    (calculated as the mean of daily values
    
    Hourly data was use to calculate daily
    means
    
    City-wide avg used)
    Mean (SD): 19.6 (9.4)
    Percent! les:
    25th: 14.6
    50th: 18.1
    75th: 22.7
    
    Range (Min, Max): (4.9,171.7)
    
    Monitoring Stations: 5
    
    Copollutant  (correlation):
    By trimesters:
    PM10T1:
    PM10T2:r = 0.12
    PM,oT3:r = -0.55
    03T1:r = 0.77
    03T2:r = 0.28
    03T3:r = -0.61
    N02T1:r = 0.32
    N02T2:r = -0.65
    N02T3:r = -0.17
    visibility reducing particles (bsp)
    T1:r = 0.82
    visibility reducing particles (bsp)
    T2:r = -.15
    visibility reducing particles (bsp)
    T3:r = -0.50
    PM10T1:r = 0.12
    PM10T2:
    PM,0T3:r = 0.04
    03T1:r = -0.11
    03T2:r = 0.80
    03T3:r = 0.18
    N02T1:r = 0.77
    N02T2:r = 0.25
    N02T3:r = -0.72
    visibility reducing particles (bsp)
    T1:r = 0.23
    visibility reducing particles (bsp)
    T2:r = 0.80
    visibility reducing particles (bsp)
    T3:r = -0.24
    PM10T1:r = -0.55
    PM10T2:r = 0.04
    PMi0T3:	
    PM Increment: IQR (8.1 fjg/nr)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Change (P) in mean birth weight (g)
    associated with trimester-specific
    exposures
    Trimester 1:
    Continuous exposure: -3.2 (-11.9, 5.5)
    Quartiles of exposure:
    1:Ref
    2:-4.7 (-19.7, 10.2)
    3: 4.2 (-12.9, 21.3)
    4:-0.2 (-19.2, 18.8)
    p-trend: 0.864
    Trimester 2:
    Continuous exposure: 0.4 (-9.4,10.2)
    Quartiles of exposure:
    1:Ref
    2:12.7 (-2.3, 27.6)
    3: 7.6 (-10.6, 25.7)
    4:1.0 (-18.7, 20.7)
    p-trend: 0.922
    Trimester 3:
    Continuous exposure: 3.6 (-6.9,14.0)
    Quartiles of exposure:
    1:Ref
    2: 2.9 (-12.8, 18.7)
    3:18.5(0.0,36.9)
    4: 4.3 (-15.8, 24.4)
    p-trend: 0.524
    ORs for SGA associated with
    trimester-specific exposures
    Trimester 1:
    Continuous exposure: 1.04(0.96,1.12)
    Quartiles of exposure:
    1:Ref
    2:1.23(1.07, 1.42)
    3:1.12(0.95,1.31)
    4:1.12(0.94, 1.34)
    p-trend: 0.361
    Trimester 2:
    Continuous exposure: 0.95 (0.88,1.04)
    Quartiles of exposure:
    1:Ref
    2:0.96(0.83, 1.11)
    3:1.06 0.89, 1.25)
    4:0.98(0.81,1.18)
    p-trend: 0.962
    3: -0.02 (-0.08, 0.04)
    4: -0.02 (-0.08, 0.05)
    p-trend: 0.605
    Trimester 2:
    Continuous exposure:-0.01 (-0.04,
    December 2009
                                     E-447
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                            03T1:r = -0.56
                                                                            03T2:r = -0.18
    
                                                                            03T3:r = 0.81
    
                                                                            N02T1:r = -0.20
    
                                                                            N02T2:r = 075
    
                                                                            N02T3:r = 0.22
    
                                                                            visibility reducing particles (bsp)
                                                                            T1:r = -0.62
    
                                                                            visibility reducing particles (bsp)
                                                                            T2:r = 0.19
    
                                                                            visibility reducing particles (bsp)
                                                                            T3:r = 0.79
                                                                     0.02)
                                                                     Quartiles of exposure:
                                                                     1:Ref
                                                                     Trimester 3:
                                                                     Continuous exposure: 0.93 (0.85,1.03)
                                                                     Quartiles of exposure:
                                                                     1:Ref
                                                                     2:0.90(0.78, 1.04)
                                                                     3: 0.81  (0.68, 0.96)
                                                                     4:0.86(0.71,1.04)
                                                                     p-trend: 0.098
                                                                     Change (P) in mean head
                                                                     circumference (HC
                                                                     cm) associated with trimester-
                                                                     specific exposures
                                                                     Trimester 1:
                                                                     Continuous exposure:-0.01  (-0.04,
                                                                     0.02)
                                                                     Quartiles of exposure:
                                                                     1:Ref
                                                                     2: -0.02 (-0.07, 0.04)
                                                                     2: 0.03 (-0.02, 0.08)
                                                                     3: 0.00 (-0.06, 0.06)
                                                                     4: -0.01 (-0.08, 0.05)
                                                                     p-trend: 0.538
                                                                     Trimester 3:
                                                                     Continuous exposure: 0.02 (-0.02, 0.05)
                                                                     Quartiles of exposure:
                                                                     1:Ref
                                                                     2: 0.02 (-0.04, 0.07)
                                                                     3:0.07(0.01,0.13)
                                                                     4: 0.04 (-0.03, 0.11)
                                                                     p-trend: 0.171
                                                                     Change (P) in mean crown-heel
                                                                     length (CHL
                                                                     cm) associated with trimester-
                                                                     specific exposures
                                                                     Trimester 1:
                                                                     Continuous exposure: 0.00 (-0.05, 0.05)
                                                                     Quartiles of exposure:
                                                                     1:Ref
                                                                     2: 0.02 (-0.07, 0.11)
                                                                     3: 0.01  (-0.10, 0.11)
                                                                     4: 0.04 (-0.07, 0.16)
                                                                     p-trend: 0.511
                                                                     Trimester 2:
                                                                     Continuous exposure: 0.07 (0.01, 0.13)
                                                                     Quartiles of exposure:
                                                                     1:Ref
                                                                     2:0.10(0.01,0.18)
                                                                     3:0.11(0.00,0.21)
                                                                     4:0.13(0.01,0.24)
                                                                     p-trend: 0.049
                                                                     Trimester 3:
                                                                     Continuous exposure:-0.01  (-0.07,
                                                                     0.05)
                                                                     Quartiles of exposure:
                                                                     1:Ref
                                                                     2:-0.02 (-0.11,0.07)
                                                                     3: 0.10 (-0.01, 0.21)
                                                                     4:-0.01 (-0.13, 0.10)
                                                                     p-trend: 0.883     	
    December 2009
                             E-448
    

    -------
                   Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: (Hansen et al., 2009,
    1923621
    
    Period of Study: Jan 1997-Dec 2004
    
    Location: Brisbane, Australia
    Outcome: Birth defects- artery and
    valve, atrial and ventricular Sepal,
    conotruncal, endocardial cushion and
    mitral valve, cleft lip and palate
    
    Study Design: Case-control
    
    Covariates: Mother's age, marital
    status, indigenous status, previous
    pregnancies, last menstrual period,
    area-level socioeconomic status,
    distance to  a pollution monitor
    
    Statistical Analysis: Conditional
    logistic regression
    
    Statistical Package: R
    
    Age Groups: Neonates
    Pollutant: PM,0
    
    Averaging Time: daily
    
    Mean (SD) Unit: 18.0 pg/m3
    
    Range (Mm, Max): (4.4,151.7)
    
    Copollutant (correlation): NR
    Increment: 4pg/m
    
    Odds Ratios (96% Cl) for risk of
    defect
    Aortic Artery and Valve Defects
    All Births, Matched: 1.10 (0.76-1.56)
    Births < 12km to Monitor:
    1.83(1.16-2.98)
    Births Ł 6km to  Monitor:
    1.43(0.73-2.90)
    All Births, Unmatched: 1.09 (0.84-1.39)
    Atrial Sepal Defects
    All Births, Matched: 1.06 (0.86-1.30)
    Births < 12km to Monitor:
    1.07(0.84-1.37)
    Births < 6km to  Monitor:
    0.88(0.60-1.27)
    All Births, Unmatched: 1.14 (0.98-1.33)
    Pulmonary Artery and Valve Defects
    All Births, Matched: 0.90 (0.61-1.29)
    Births < 12km to Monitor: 0.69
    (0.43-1.08)
    Births < 6km to  Monitor:
    1.46(0.76-2.73)
    All Births, Unmatched: 0.99
    (0.78-1.24)
    Ventricular Sepal Defects
    All Births, Matched: 0.87 (0.73-1.04)
    Births < 12km to Monitor:
    0.85(0.69-1.03)
    Births < 6km to  Monitor:
    0.90(0.68-1.18)
    All Births, Unmatched: 1.15(1.02-1.30)
    Conotruncal Defects
    All Births, Matched: 0.80 (0.54-1.19)
    Births < 12km to Monitor: 0.94 (0.55-
    1.49)
    Births < 6km to  Monitor: 0.66 (0.27-
    1.45)
    All Births, Unmatched: 0.97 (0.74-1.24)
    Endocardial Cushion and Mitral Valve
    Defects
    All Births, Matched: 1.29 (0.82-2.04)
    Births < 12km to Monitor:
    1.28(0.75-2.19)
    Births < 6km to  Monitor:
    0.90(0.44-1.86)
    All Births, Unmatched: 0.94 (0.68-1.26)
    Cleft Lip
    All Births, Matched: 1.05 (0.72-1.51)
    Births < 12km to Monitor:
    1.16(0.72-1.82)
    Births < 6km to  Monitor:
    1.03(0.56-1.82)
    All Births, Unmatched: 1.01 (0.79-1.27)
    Cleft Palate
    All Births, Matched: 0.69 (0.50-0.93)
    Births < 12km to Monitor:
    0.53 (0.29-0.87)
    Births Ł 6km to  Monitor:
    0.71 (0.49-1.00)
    All Births, Unmatched: 0.89 (0.72-1.10)
    Cleft Lip with or without Cleft Palate
    All Births, Matched: 1.05 (0.84-1.30)
    Births < 12km to Monitor:
    1.03(0.79-1.34)
    Births Ł 6km to  Monitor:
    0.83(0.58-1.19)
    All Births, Unmatched: 1.04 (0.89-1.21)\
    December 2009
                                      E-449
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Jalaludin et al. (2007,
    1566011
    
    Period of Study: 1998-2000
    
    Location: Sydney, Australia
    Outcome: Gestational age
    (categorized: preterm birth: <37wk
    
    term birth: > 37 wk but <42 wk)
    
    Age Groups: Infants
    
    Study Design: Cross-sectional
    
    N: 123,840 singleton births of >20 wk
    gestation
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Sex of child, maternal age,
    maternal smoking during pregnancy,
    gestational age at first antenatal visit,
    whether mother identifies as being
    Aboriginal or Torres Strait Islander,
    whether first pregnancy, season of
    conception, SES, (temperature and
    relative humidity were not significant in
    single variable models and therefore,
    were not included)
    
    Season: Examined as covariate and
    effect modifier
    
    Dose-response Investigated?  No
    
    Statistical Package: SASvS
    Pollutant: PM,0
    
    Averaging Time: 24 h avg used to
    calculate the mean concentration over
    the first trimester, the 3 mo preceding
    birth, the first month after the estimated
    date of conception, and the month prior
    to delivery
    Mean (SD): (24 h avg)
    All yr: 16.3 (6.38)
    Summer: 18.2 (7.20)
    Fall: 17.0 (6.23)
    Winter: 14.5 (5.57)
    Spring: 15.7 (5.82)
    Monitoring Stations: 14 stations within
    the Sydney metropolitan area (levels
    avgd to provide 1 estimate for the entire
    study area)
    Copollutant (correlation):
    PM10
    PM25(r = 0.83)
    CO (r = 0.28)
    N02(r = 0.48)
    03(r = 0.50)
    S02(r = 0.42)
    Notes: Correlations between
    monitoring stations measuring PM10
    ranged from 0.67 to 0.91
    PM Increment: 1 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    ORs (air pollutant concentration during
    the 1st trimester and preterm birth by
    season)
    Fall: 1.462 (1.267, 1.688)
    Winter: 1.343 (1.190,1.516)
    Spring: 1.119 (0.973,1.288)
    Summer: 0.913 (0.889, 0.937)
    ORs (air pollutant concentrations during
    different exposure periods and preterm
    birth
    for all of Sydney and among only those
    residing within 5 km of a monitoring
    station)
    1 month preceding birth
    Sydney: 0.991 (0.979,1.003)
    5km: 1.008 (0.993, 1.022)
    3 mo preceding birth
    Sydney: 0.989 (0.975,1.004)
    5km: 1.012 (0.995,1.030)
    1st month of gestation
    Sydney: 0.983 (0.973, 0.993)
    5km: 0.957 (0.914, 1.002)
    1st trimester
    Sydney: 0.987 (0.973,1.001)
    5km: 1.009 (0.978,1.041)
    Notes: Authors note that effect of PM10
    on preterm  birth for infants conceived
    during the fall did not remain in 2
    pollutant models (ORs between 0.77
    and 1.04)
    Reference: Kaiser et al. (2004,
    0766741
    
    Period of Study: 1995-1997
    Location: 25 U.S. counties (23
    metropolitan areas): Jackson, AL
    
    Fresno, CA
    Los Angeles, CA
    Sacramento, CA
    San Diego, CA
    San Francisco, CA
    Denver, CO
    Hartford, CT
    Cook, IL
    Baltimore, MD
    Wayne, Ml
    St. Louis, MO
    Rrrinv MV
    DlONX, IN I
    l/lnne MV
    r\ings, NY
    New York, NY
    Philadelphia, PA
    El Paso, TX
    Harris TX
    Dallac TY
    Udlldo, I A
    Oklahoma, OK
    Tulsa, OK
    Providence, Rl
    Salt Lake City, UT
    King, WA
    Milwaukee, Wl
    
    
    Outcome: Postneonatal death:
    
    All cause, SIDS (798.0)
    Respiratory disease (460-519)
    Age Groups: Infants between 1-12 mo
    
    Study Design: Attributable risk
    assessment
    N: 700,000 infants (# deaths NR)
    Statistical Analyses: Risk assessment
    methods described in: Kunzli et al.
    Public-health impact of outdoor and
    traffic-related air pollution: a European
    assessment. Lancet 2000, 356: 795-
    Qf"M
    OU1.
    Covariates: Maternal education,
    maternal ethnicity, parental marital
    status, maternal smoking during
    pregnancy, infant's month and yr of
    birth, avg temperature in the first 2 mo
    of life
    Season: All
    adjusted for month/yr of birth
    Dose-response Investigated? NR
    Statistical Package: NR
    Lags Considered: Annual, county-level
    mean
    Pollutant: PM,0
    
    Averaging Time: "annual mean levels"
    in each county
    Mean (SD): 28.4
    Range (Min, Max):
    County range: 18.0,44.8
    Monitoring Stations: NR
    Notes: 14 out of 25 counties had PMi0
    levels >25 pg/m3
    
    
    
    
    
    
    
    
    
    
    
    PM Increment: Analysis 1 :
    
    16.4 pg/m3 (difference between
    reference level of 12 pg/m3 and
    observed mean level of 28.4 pg/m )
    Analysis 2:
    
    13 pg/m3 (difference between reference
    level of 12 pg/m3 and 25 pg/m3)
    AR Estimate [Lower Cl, Upper Cl]:
    Analysis 1 :
    All cause 6% [3, 11]
    SIDS 16% [9, 23]
    Respiratory 24% [7, 44]
    Attributable* deaths per 100,000
    All cause 14.7 [7.3, 25.6]
    SIDS 11. 7 [6.8, 16.6]
    Respiratory 2.3 [0.7, 4.1]
    Analysis 2:
    All cause 5% [2, 8]
    SIDS 12% [7, 18]
    Respiratory 19% [6, 34]
    Attributable* deaths per 100,000
    All cause 10.9 [5.5, 19.1]
    SIDS 9.0 [5.3, 12.8]
    Respiratory 1.8 [0.5, 3.2]
    Notes: -Authors did not extrapolate
    attributable cases below 12 pg/m3 (i.e.,
    reference level was set at 12 pg/m )
    -Attrihiit^hla rielxe •am K^eaH An tha DDe
                                                                                                                  reported by Woodruff et al, 1997 for a
                                                                                                                  10 pg/m  increase:
    
                                                                                                                  All cause 1.04 [1.02-1.07]
    
                                                                                                                  SIDS 1.12 [1.07, 1.17]
    
                                                                                                                  Respiratory 1.20 [1.06,1.36]
    December 2009
                                     E-450
    

    -------
                   Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: (Kim et al, 2007,1566421
    
    Period of Study: May 2001-May 2004
    
    Location: Seoul, Korea
    Outcome (ICD9 and ICD10): LBW (low
    birth weight, less than 2500 g at later
    than gestational week 37), premature
    delivery (birth before the completion of
    the 37th week), stillbirth (intrauterine
    fetal death), IUGR (birth weight lower
    than the 10th percentile for the given
    gestational  age), and congenital
    anomaly (a defect in the infant's body
    structure)
    
    Age Groups: Infants
    
    Study Design: Cross-sectional (women
    visiting the clinic for prenatal care were
    recruited with follow-up until discharge
    after delivery)
    
    N: 1514 observations (births)
    
    Statistical Analyses: Multiple logistic
    and linear regression (in addition, for
    birth weight, used generalized additive
    model to account for long-term trends
    and nonlinear relationships between the
    response variable and the predictors,
    and to produce smoothed  plots of the
    relationship between PM and birth
    weight)
    
    Covariates: Adjustment 1: infant sex,
    infant order, maternal age and
    education, paternal education, season
    of birth
    
    Adjustment 2: adjustment  1 factors plus
    alcohol, maternal BMI, maternal weight
    prior to delivery
    
    (collected information on smoking, ETS,
    parity, past  history of illnesses, history
    of illnesses during pregnancy but did
    not use in analyses due to small
    numbers or non-significance)
    
    Season: Adjusted for season of
    delivery
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS 8.01, S-Plus
    2000
    Pollutant: PM,0
    
    Averaging Time: Used hourly
    exposure levels to calculate avg
    exposure levels at each trimester, each
    month of pregnancy, and 6 wk before
    delivery from the nearest monitoring
    station (based on home address of
    mother)
    
    Also created categories within each
    pregnancy period (<25th percentile
    [referent], 25th to 50th percentile, and
    >50th percentile)
    
    Mean (SD): Range of PM means
    across pregnancy periods: 88.7-89.7
    
    Monitoring Stations: 27 stations
    PM increment: 10 pg/m
    
    Preterm:
    1st Trimester Odds Ratios:
    Crude: 0.95 (0.90,1.01)
    Adj 1:0.93 (0.87, 1.00)
    Adj 2: 0.93 (0.85, 1.01)
    2nd Trimester Odds Ratios:
    Crude: 0.99 (0.94,1.06)
    Adj 1:0.98 (0.92, 1.04)
    Adj 2:1.00 (0.93, 1.07)
    3rd Trimester Odds Ratios:
    Crude: 1.02 (0.98,1.06)
    Adj 1:1.05 (1.00, 1.10)
    Adj 2:1.05 (0.99, 1.11)
    LBW:
    1st Trimester Odds Ratios:
    Crude: 1.02 (0.93,1.12)
    Adj 1:1.03 (0.93, 1.14)
    Adj 2:1.07 (0.96, 1.19)
    2nd Trimester Odds Ratios:
    Crude: 1.03 (0.94,1.14)
    Adj 1:1.04 (0.93, 1.17)
    Adj 2:1.07 (0.94, 1.22)
    3rd Trimester Odds Ratios:
    Crude: 1.04 (0.97,1.11)
    Adj 1:1.05 (0.97, 1.14)
    Adj 2:1.05 (0.96, 1.16)
    IUGR:
    1st Trimester Odds Ratios:
    Crude: 1.07 (0.97,1.19)
    Adj 1:1.07 (0.95, 1.21)
    Adj 2:1.14 (0.99, 1.31)
    2nd Trimester Odds Ratios:
    Crude: 0.97 (0.85,1.12)
    Adj 1:0.97 (0.82, 1.13)
    Adj 2: 0.93 (0.77, 1.13)
    3rd Trimester Odds Ratios:
    Crude: 0.82 (0.68, 0.99)
    Adj 1:0.88 (0.72, 1.08)
    Adj 2: 0.85 (0.67, 1.08)
    Birth defect:
    1st Trimester Odds Ratios:
    Crude: 1.08 (0.98,1.20)
    Adj 1:1.12 (1.00, 1.25)
    Adj 2:1.08 (0.95, 1.22)
    2nd Trimester Odds Ratios:
    Crude: 1.09 (0.99,1.21)
    Adj 1:1.11 (0.98, 1.26)
    Adj 2:1.16 (1.00, 1.34)
    3rd Trimester Odds Ratios:
    Crude: 1.00 (0.90,1.11)
    Adj 1:0.97 (0.86, 1.08)
    Adj 2: 0.97 (0.87, 1.10)
    Stillbirth:
    1st Trimester Odds Ratios:
    Crude: 0.83 (0.76, 0.90)
    Adj 1:0.93 (0.85, 1.02)
    Adj 2: 0.95 (0.85, 1.02)
    2nd Trimester Odds Ratios:
    Crude: 0.99 (0.93,1.05)
    Adj 1:1.03 (0.95, 1.11)
    Adj 2:1.07 (0.98, 1.17)
    3rd Trimester Odds Ratios:
    Crude: 1.14 (1.10,1.18)
    Adj 1:1.09 (1.04, 1.15)
    Adj 2:1.08 (1.02, 1.14)
    LBW (categorical PM exposure):
    1st Trimester ORs:
    <25th:1.0
    25th-50th:0.5(0.1,3.2)
    >50th:1.0(0.3, 3.8)
    3rd Trimester ORs:
    <25th:1.0
    25th-50th:1.3(0.2, 10.4)
    >50th: 3.0 (0.5, 18.5)
    6 wk before birth ORs:
    <25th:1.0
    December 2009
                                     E-451
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                25th-50th: 3.2 (0.3, 33.7)
                                                                                                                >50th: 5.2 (0.6, 47.6)
                                                                                                                Changes in Birth Weight (96%CI) per
                                                                                                                10 ug/m3 increase in PM
                                                                                                                concentration:
                                                                                                                1st trimester: 7.8 (1.2,14.5)
                                                                                                                2nd trimester:-0.3 (-7.3, 6.8)
                                                                                                                3rd trimester:-2.1 (-7.5,3.4)
                                                                                                                1st month: 4.4 (-1.0, 9.8)
                                                                                                                2nd month: 6.4 (0.6,12.2)
                                                                                                                3rd month: 4.3 (-1.5, 10.2)
                                                                                                                4th month: 3.0  (-3.7, 9.6)
                                                                                                                5th month:-3.9 (-10.5, 2.7)
                                                                                                                6th month: 0.1
                                                                                                                (-5.7, 5.8)
                                                                                                                7th month: 0.1  (-5.1,5.3)
                                                                                                                8th month: 0.0
                                                                                                                9th month: 1.8
                                                                                          -4.5, 4.5)
                                                                                          -2.3, 5.9)
                                                                                                                 Last 6 wk: -4.8 (-9.9, 0.4)
    Reference: Lee et al. (2003, 0432021
    
    Period of Study: Jan 1996-Dec 1998
    
    Location: Seoul,  South Korea
    Outcome: Low birth weight (LBW),
    <2500 g
    
    Age Groups: Child-bearing age women
    and their newborn children-delivered at
    37-44 gestational wk
    
    Study Design: Cross-section
    
    N: 388,905 full-term single births
    
    Statistical Analyses: Generalized
    additive model, LOESS, Akaike's
    criterion,
    
    Covariates:  Infant sex, birth order,
    maternal age, parental education level,
    time trend and gestational age.
    
    Season: All
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    Pollutant: PM10
    
    Averaging Time: Arithmetic avg of
    hourly measurements at 20 stations
    
    Mean (SD): 71.1(30.1)
    Percent! les:
    25th: 47.4
    60th(Median): 67.6
    76th: 89.3
    Range (Mm, Max): 18.4, 236.9
    
    Monitoring Stations: 20
    Copollutant (correlation):
    1st trimester:
    PM10-CO: 0.47
    PMio-S02: 0.78
    PM10-N02: 0.66
    2nd trimester:
    PMio-CO: 0.68
    PM10-S02: 0.82
    PM10-N02: 0.81
    3rd trimester:
    PM10-CO: 0.69
    PM10-S02: 0.85
    PMio-N02: 0.80	
    PM Increment: IQR, 41.9
    
    RR Estimate [Lower Cl, Upper Cl]:
    
    1st trimester: 1.03 [1.00,1.07]
    
    2nd trimester: 1.04 [1.00,1.08]
    
    3rd trimester: 1.00 [0.95,1.04]
    
    All trimesters: 1.06 [1.01,1.10]
    
    Low exposure in last 5 mo using IQR
    during last 5 mo: 0.94 [0.85,1.05]
    
    Low exposure in first 5 mo using IQR
    during first 5 mo:  1.04 [1.01,1.08]
    
    Notes: Birth weight was decreased by
    19.6 g for an IQR increase in the 2nd
    trimester.
    
    The OR for LBW increased for female
    children, fourth or higher order child,
    mother <20 yr of age, and low parental
    education level.
    December 2009
                                     E-452
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Leem et al. (2006, 0898281
    
    Period of Study: 2001-2002
    
    Location: Incheon,  Korea
    Outcome (ICD9 and ICD10): Age
    Groups: Pre-term delivery
    
    Study Design: Cross-sectional
    
    N:Cases: 2,082
    
    Controls: 50,031
    
    Statistical Analyses: Log-binomial
    regression (corrected for overdispersion
    
    Used the log link function)
    
    Covariates: Maternal age, parity, sex,
    season of birth, and education level of
    each parent
    
    Season: Controlled as a covariate
    
    Dose-response Investigated? Yes,
    assessed quartiles of exposure
    
    Statistical Package: NR
    Pollutant: PM,0
    
    Averaging Time: Trimesters (daily
    hourly data used to calculate)
    Range (Min, Max): Reported ranges
    within quartiles by trimester:
    1st Trimester:
    4:64.57-106.39
    3: 53.84-64.56
    2: 45.95-53.83
    1:26.99-45.94
    3rd Trimester:
    4: 65.63-95.91
    3: 56.07-65.62
    2: 47.07-56.06
    1:33.12-47.06
    Monitoring Stations: 27 monitoring
    stations
    
    Pollutant levels for each area were
    predicted from the levels recorded at
    the monitors using ordinary block
    kriging
    
    Copollutant (correlation):
    
    S02(r = 0.13)
    
    N02(r = 0.37)
    
    CO (r = 0.27)
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Crude and Adjusted RRfor preterm
    delivery and exposure during the 1st
    trimester
    Crude
    Quartiles of exposure:
    4:1.07(0.95, 1.21)
    3:1.02  0.90, 1.15)
    2:1.06(0.94,1.20)
    1:1.00
    Adjusted
    Quartiles of exposure:
    4:1.27(1.04,1.56)
    3:1.13  0.94, 1.37)
    2:1.14(0.97,1.34)
    1:1.00
    p-trend: 0.39
    Crude and Adjusted RRfor preterm
    delivery and exposure during the 3rd
    trimester
    Crude
    Quartiles of exposure:
    4:1.06(0.94,1.20)
    3:1.06(0.94, 1.19)
    2:1.05  0.93, 1.18)
    1:1.00
    Adjusted
    Quartiles of exposure:
    4:1.09(0.91,1.30)
    3:1.04(0.90, 1.21)
    2:1.05  0.91, 1.20)
    1:1.00
    p-trend: 0.33	
    Reference: Lin et al. (2004, 0957871
    
    Period of Study: Jan 1998-Dec 2000
    
    Location: Sao Paulo, Brazil
    Outcome: Neonatal death
    
    Age Groups: Neonates (infants 0-28
    days after birth)
    
    Study Design: Time series
    
    N: 1096 days, 6697 deaths
    
    Statistical Analyses: Poisson
    regression (GAM)
    
    Covariates: Non-parametric LOESS
    smoothers to control for: time (long term
    trend), temperature, humidity, and day
    of week
    
    Also controlled for holidays with linear
    term
    
    Season: All
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: Lag 0, "ma  from 2 to
    7 days"
    
    Notes: No explicit control for season
    apart from temperature
    Pollutant: PM,0
    
    Averaging Time: Daily values
    
    Mean (SD): 48.62 (21.18)
    
    Range (Min, Max): 13.9,157.3
    
    Monitoring Stations: NR (indicated
    more than 1)
    
    Copollutant (correlation):
    
    CO r = 0.71
    
    N02r = 0.76
    
    S02r = 0.80
    
    03r = 0.36
    PM Increment: 1 pg/m
    
    Log relative rate (standard error) lag
    
    Single pollutant model
    
    0.0017 (0.0008) lag 0
    
    This translates to a 4.0% [95% Cl: 0.3,
    7.9] increase in neonatal mortality for a
    23.3 pg/m3 increase in PM,0
    
    Two-pollutant model
    
    0.0000 (0.0011) lag 0
    
    Notes: -In two-pollutant model with
    PM10 and S02 (which are highly
    correlated), effect of PM disappeared
    and effect of S02 remained constant
    
    - Results from pollutant ma from
    2-7 days not reported, authors indicate
    effects only found for lag 0 (same day
    levels)
    
    - Confidence intervals reported in
    abstract are incompatible with
    ps/standard errors and plotted results in
    text: abstract indicates a 4% increase in
    mortality with 95% Cl: 2-6 for a
    23.3 pg/m3 increase in PM10
    December 2009
                                     E-453
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: (Lin et al, 2004, 0898271
    
    Period of Study: 1995-1997
    
    Location: Taipei and Kaoshiung,
    Taiwan
    Outcome: Low birth weight (<2500
    grams)
    
    Age Groups: Newborns
    
    Study Design: Cross-sectional
    
    N: 92,288 infants
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Gender, birth order,
    gestational weeks, season of birth,
    maternal age, maternal education,
    copollutants
    
    Season: All
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    
    Lags Considered: The 9-month
    pregnancy period for each infant,  and
    each trimester
    Pollutant: PM,0
    
    Averaging Time: NR, "daily
    measurements"
    
    Mean (SD): Reported by monitoring
    station: Taipei:
    1.48.78
    2. 46.29
    3. 48.79
    4. 50.80
    5. 52.54
    Kaohsiung
    1.69.99
    2. 63.39
    3. 64.89
    4. 75.79
    5. 77.27
    Monitoring Stations:
    
    10 (5 in each city)
    
    Notes: All pregnant women/infants
    included in study lived within 3 km of an
    air quality monitoring station
    
    Pollution assigned based on nearest air
    quality station to the maternal residence
    
    Co-pollutant: CO, S02, 03, N02
    PM Increment: Tertiles
    Entire pregnancy
    T1:<46.4ppb
    T2: 46.4-63.1 ppb
    T3: >63.1 ppb
    First trimester
    T1:<45.8ppb
    T2: 45.8-67.6 ppb
    T3: >67.6 ppb
    Second trimester
    T1:<44.6ppb
    T2: 44.6-64.2 ppb
    T3: >64.2 ppb
    Third trimester
    T1:<43.7ppb
    T2: 43.7-63.7 ppb
    T3: >63.7 ppb
    RR Estimate [Lower Cl, Upper Cl]
    Entire pregnancy
    T1:1.00
    T2: 0.96 [0.83, 1.11]
    T3: 0.87 [0.71, 1.05]
    First trimester
    T1:1.00
    T2: 0.96 [0.84, 1.09]
    T3: 0.97 [0.80, 1.17]
    Second trimester
    T1:1.00
    T2:1.03 [0.90, 1.17]
    T3:1.00 [0.83, 1.21]
    Third trimester
    T1:1.00
    T2:1.02 [0.90, 1.16]
    T3: 0.97 [0.81, 1.17]
    Notes: RR for births in Kaoshiung vs.
    Taipei: 1.13 [1.03,1.24]
    Reference: Lipfert et al. (2000, 0041031
    
    Period of Study: 1990
    
    Location: U.S.
    Outcome: Infant mortality
    
    Including respiratory mortality
    (traditional definition, ICD9 460-519),
    expanded definition (adds ICD9 769
    and 770)
    
    Age Groups: Infants
    
    Study Design: Cross-sectional
    
    N: 2,413,762 infants in 180 counties
    (Ns differ for various models)
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Mother's smoking,
    education, marital status,  and race
    
    Month of birth
    
    And county avg heating degree days
    
    Dose-response Investigated? NR
    
    Statistical Package: NR
    Pollutant: PM,0
    
    Averaging Time: Yearly avg used
    
    Mean (SD): 33.1 (9.17) (based on 180
    counties)
    
    Range (Min, Max): (16.9, 59)
    
    Monitoring Stations: NR
    
    Copollutant (correlation):
    
    PM10
    
    S042"(r = 0.10)
    
    NSPMio-non-sulfate portion of PMi0
    (r = 0.91)
    
    CO (r = 0.27)
    
    S02(r = 0.04)
    
    Notes: TSP-based sulfate was adjusted
    for compatibility with the PMio-based
    data
    PM Increment: NR (present regression
    coefficients)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Presented regression coefficients
     standard errors)
     3 PM exposures regressed jointly)
    bold = p <0.05
    Cause of death: All
    Birth weight: All
    PM,,: 0.0114 (0.0015)
    S04:-0.0002 (0.0061)
    NSPM10: 0.0115 (0.0014)
    Cause of death: All
    Birth weight: LBW
    PM,,: 0.0088 (0.0019)
    S04 : 0.0265 (0.0080)
    NSPM,0: 0.0086 (0.0020)
    Cause of death: All
    Birth weight: normal
    PM,n: 0.0092 (0.0024)
    S04 : -0.0488 (0.0098)
    NSPM10: 0.0096 (0.0024)
    Cause of death: All neonatal
    Birth weight: All
    PM,,: 0.0126 (0.0018)
    S04 :0.0267 (0.0076)
    NSPM10: 0.0126 (0.0018)
    Cause of death: All neonatal
    Birth weight: LBW
    PM,,: 0.0086 (0.0022)
    S04 :0.0388 (0.0088)
    NSPM,0: 0.0093 (0.0022)
    Cause of death: All neonatal
    Birth wt: normal
    PM,n: 0.0123 (0.0041)
    SO/':-0.0334 (0.0169)
    NSPM10: 0.0125 (0.0040)
    Cause of death: All post neonatal
    Birth wt: All
    December 2009
                                     E-454
    

    -------
                  Study                      Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                              PM,,: 0.0091 (0.0024)
                                                                                                              S04:-0.0474 (0.0100)
                                                                                                              NSPM10: 0.0096 (0.0024)
                                                                                                              Cause of death: All post neonatal
                                                                                                              Birth wt: LBW
                                                                                                              PM1fl: 0.0096 (0.0043)
                                                                                                              S04:-0.0247 (0.0173)
                                                                                                              NSPM,o: 0.0101  (0.0042)
                                                                                                              Cause of death: All post neonatal
                                                                                                              Birth wt: normal
                                                                                                              PM,n: 0.0074 (0.0030)
                                                                                                              S04 : -0.0569 (0.0121)
                                                                                                              NSPM10: 0.0080 (0.0029)
                                                                                                              Cause of death: SIDS
                                                                                                              Birth weight: All
                                                                                                              PM,n: 0.0138 (0.0038)
                                                                                                              S04:-0.1078 (0.0151)
                                                                                                              NSPM10: 0.0149 (0.0037)
                                                                                                              Cause of death: SIDS
                                                                                                              Birth weight: LBW
                                                                                                              PIVU 0.0115 (0.0088)
                                                                                                              S04:-0.1378 (0.0337)
                                                                                                              NSPM,0: 0.0146 (0.0085)
                                                                                                              Cause of death: SIDS
                                                                                                              Birth weight: normal
                                                                                                              PM,n: 0.0137 (0.0042)
                                                                                                              S04:-0.0995 (0.0168)
                                                                                                              NSPM10: 0.0147 (0.0041)
                                                                                                              Cause of death: All respiratory (ICD9:
                                                                                                              460-519, 769, 770)
                                                                                                              Birth weight: All
                                                                                                              PM,n: 0.0168 (0.0034)
                                                                                                              S04: 0.0706 (0.0146)
                                                                                                              NSPM10: 0.0166 (0.0034)
                                                                                                              Cause of death: All respiratory (ICD9:
                                                                                                              460-519, 769, 770)
                                                                                                              Birth weight: LBW
                                                                                                              PM,n: 0.0144 (0.0038)
                                                                                                              S04: 0.0821 (0.0158)
                                                                                                              NSPM10: 0.0139 (0.0038)
                                                                                                              Cause of death: All respiratory (ICD9:
                                                                                                              460-519, 769, 770)
                                                                                                              Birth weight: normal
                                                                                                              PM,n: 0.0177 (0.0091)
                                                                                                              S04 :0.0001 (0.0392)
                                                                                                              NSPM10: 0.0118 (0.0090)
                                                                                                              Cause of death: Respiratory disease
                                                                                                              (ICD9: 460-519)
                                                                                                              Birth weight: All
                                                                                                              PM,n: 0.0133 (0.0089)
                                                                                                              S04 :0.0093 (0.0384)
                                                                                                              NSPM10: 0.0134 (0.0089)
                                                                                                              Cause of death: Respiratory disease
                                                                                                              (ICD9: 460-519)
                                                                                                              Birth weight: LBW
                                                                                                              PM,n: 0.0092 (0.0137)
                                                                                                              S04 :0.0434 (0.0580)
                                                                                                              NSPM10: 0.0089 (0.0138)
                                                                                                              Cause of death: Respiratory disease
                                                                                                              (ICD9: 460-519)
                                                                                                              Birth weight: normal
                                                                                                              PM,n: 0.0126 (0.0120)
                                                                                                              S04:-0.0177 (0.0509)
                                                                                                              NSPMy 0.0128 (0.0119)
                                                                                                              Associations with SIDS by smoking
                                                                                                              status
                                                                                                              Smoking status: Yes
                                                                                                              Birth weight: Normal
                                                                                                              PM1fl: 0.0202 (0.0073)
                                                                                                              S04 : -0.0722 (0.0284)
                                                                                                              NSPM,0: 0.0206 (0.0071)
                                                                                                              Smoking status: No
                                                                                                              Birth weight: Normal
                                                                                                              PMin:0.0104
    0.0051)
    0.021)
                                                                                                              SCV':-0.114
                                                                                                              NSPM10: 0.0117 (0.005)
                                                                                                              Smoking status: Yes
                                                                                                              Birth weight: LBW
    December 2009                                                   E-455
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                               PM,,: 0.0322 (0.0130)
                                                                                                               S04  : -0.0958 (0.0483)
                                                                                                               NSPM10: 0.0345 (0.0125)
                                                                                                               Smoking status: No
                                                                                                               Birth weight: LBW
                                                                                                               PM,,:-0.0044 (0.012)
                                                                                                               S04  : -0.0172 (0.047)
                                                                                                               NSPM,0: -0.0007 (0.012)
                                                                                                               Mean risks (95%CI) between post
                                                                                                               neonatal SIDS among normal birth
                                                                                                               weight babies
                                                                                                               pollutants regressed one at a time
                                                                                                               PM,,: 1.20 (1.02, 1.42)
                                                                                                               S04  : 0.43 (0.37, 0.51)
                                                                                                               NSPM10:1.33 (1.18, 1.50)
    Reference: Maisonet et al. (2001,
    0166241
    Period of Study: 1994-1996
    Location: Northeastern U.S. (6 cities:
    Boston, Hartford, Philadelphia,
    Pittsburgh, Springfield, Washington DC)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Outcome: Low birth weight (LBW):
    infants with a birth weight <2,500 g and
    having a gestational age between 37
    and 44 wk
    Age Groups: Term live births
    (singleton)
    Study Design: Cross-sectional
    N: 89,557 infants
    
    Statistical Analyses: Logistic
    regression (LBW) and linear regression
    (for reductions in birth weight)
    
    Covariates: Gestational age, gender,
    birth order, maternal age, race/ethnicity,
    yr of education, marital status,
    adequacy of prenatal care, previous
    induced or spontaneous abortions,
    weight gain during pregnancy, maternal
    prenatal smoking, and alcohol
    consumption
    Season
    Season: Yes, as covariate
    Dose-response Investigated? Yes,
    categorical exposure variables
    assessed
    
    Statistical Package: STATA
    Pollutant: PM,0
    Averaging Time: Trimester avg
    calculated using 24-h measurements
    taken every 6 days
    Range (Min, Max): Ranges for
    categories of exposure:
    1st Trimester
    <25th: <24.821
    25 to <50th: 24.821, 30.996
    50 to <75th: 30.997, 36.142
    75 to <95th: 36.143, 46.547
    > 95th :> 46. 548
    2nd Trimester
    <25th: <24.702
    25 to <50th: 24.702, 30.294
    50 to <75th: 30.295, 35.410
    75 to <95th: 35.411, 43.928
    > 95th :> 43. 929
    3rd Trimester
    <25th: <24.702
    25 to <50th: 24.702, 30.162
    50 to <75th: 30.163, 35.642
    75 to <95th: 35.643, 43.588
    > 95th :> 43. 589
    Monitoring Stations: 3-4 per city
    Copollutants: CO, S02
    
    
    
    PM Increment: 10 pg/m3 for analyses
    assessing exposures continuously
    Effect Estimate [Lower Cl, Upper Cl]:
    ORs for term LBW by trimester
    1st Trimester Crude
    <25th:1.00
    25 to <50th: 1.02 (0.90, 1.14)
    50to<75th:0.90 0.65, 1.24
    75to<95th:0.87 0.58,1.30
    > 95th: 0.89 (0.60 1.33)
    
    
    Continuous: 0.93 (0.77, 1.13)
    1st Trimester Adjusted
    <25th:1.00
    25to<50th' 1 02 094 1 11
    50to<75th'090 073 1 03
    75 to <95th: 0.85 (0.73, 1.00
    > 95th: 0.83 (0.70, 0.97)
    
    
    
    
    Continuous: 0.93 (0.85, 1.00)
    2nd Trimester Crude
    <25th' 1 00
    
    25to<50th:1.01 (0.93, 1.10)
    50 to <75th: 0.90 (0.66, 1.21)
    75to<95th:0.92(0.62, 1.34)
    > 95th: 0.90 (0.61 1.33)
    Continuous: 0.95 (0.78, 1.16)
    2nd Trimester Adjusted
    <25th:1.00
    
    25 to <50th: 1.06 (0.97, 1.15)
    50to<75th:0.95 0.85, 1.07
    75to<95th'091 079 1 05
    > 95th: 0.77 (0.63 0.95)
    
    
    
    Continuous: 0.93 (0.85, 1.02)
    
    
    
    
    
    
    
    
    
    
    
    
    3rd Trimester Crude
    <25th:1.00
    25to<50th:0.94 0.85, 1.05
    50to<75th:0.86 0.58,1.25
    
    
    
    
                                                                                                               75 to <95th: 0.86 (0.57, 1.29)
                                                                                                               > 95th: 0.92 (0.61, 1.38)
                                                                                                               Continuous: 0.95 (0.75,1.20)
                                                                                                               3rd Trimester Adjusted
                                                                                                               <25th:1.00
                                                                                                               25 to <50th: 0.98 (0.87, 1.10)
                                                                                                               50 to <75th: 0.92 (0.76, 1.11)
                                                                                                               75to<95th:0.88(0.75, 1.04)
                                                                                                               > 95th: 0.91 (0.77, 1.07)
                                                                                                               Continuous: 0.96 (0.88,1.06)
                                                                                                               Adjusted ORs by race/ethnicity
                                                                                                               Whites:
                                                                                                               1st Trimester
                                                                                                               <25th:1.00
                                                                                                               25 to <50th: 1.13 (0.96, 1.33)
                                                                                                               50 to <75th: 1.00 (0.92, 1.08)
                                                                                                               75to<95th:1.00 0.91, 1.09)
                                                                                                               > 95th: 0.92 (0.81, 1.04)
                                                                                                               Continuous: 0.94 (0.90, 0.98)
                                                                                                               2nd Trimester
                                                                                                               <25th:1.00
                                                                                                               25 to <50th: 0.88 (0.77, 1.02)
                                                                                                               50to<75th:0.95 0.89, 1.02
                                                                                                               75to<95th:0.95 0.84,1.07
                                                                                                               > 95th: 0.89 (0.64, 1.26)
                                                                                                               Continuous: 0.96 (0.89,1.04)
    December 2009
                             E-456
    

    -------
                  Study                       Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                                3rd Trimester
                                                                                                                <25th:1.00
                                                                                                                25 to <50th: 0.84 (0.64, 1.11)
                                                                                                                50 to <75th: 0.91 (0.83, 1.01)
                                                                                                                75 to <95th: 0.80 0.71,0.90)
                                                                                                                > 95th: 1.03 (0.86, 1.24)
                                                                                                                Continuous: 0.95 (0.90,1.00)
                                                                                                                African Americans:
                                                                                                                1st Trimester
                                                                                                                <25th:1.00
                                                                                                                25to<50th:1.01  0.98, 1.05
                                                                                                                50to<75th:0.88 0.79,0.98
                                                                                                                75 to <95th: 0.83 (0.70, 0.97)
                                                                                                                > 95th: 0.81 (0.67,0.99)
                                                                                                                Continuous: 0.93 (0.85,1.01)
                                                                                                                2nd Trimester
                                                                                                                <25th:1.00
                                                                                                                25 to <50th: 1.10(0.93, 1.30)
                                                                                                                50 to <75th: 0.95 (0.80, 1.12)
                                                                                                                75to<95th:0.88(0.69, 1.11)
                                                                                                                > 95th: 0.75 (0.54, 1.03)
                                                                                                                Continuous: 0.92 (0.80,1.05)
                                                                                                                3rd Trimester
                                                                                                                <25th:1.00
                                                                                                                25 to <50th: 1.08 (0.92, 1.27)
                                                                                                                50to<75th:0.89 0.70, 1.12
                                                                                                                75to<95th:0.94 0.75,1.18
                                                                                                                > 95th: 0.83 (0.71, 0.97)
                                                                                                                Continuous: 0.99 (0.87,1.11)
                                                                                                                Hispanics:
                                                                                                                1st Trimester
                                                                                                                <25th:1.00
                                                                                                                25 to <50th: 0.83 (0.64, 1.06)
                                                                                                                50 to <75th: 0.86 (0.70, 1.05)
                                                                                                                75 to <95th: 0.79 (0.68, 0.93)
                                                                                                                > 95th: 1.36 (1.06, 1.75)
                                                                                                                Continuous: 0.96 (0.84,1.09)
                                                                                                                2nd Trimester
                                                                                                                <25th:1.00
                                                                                                                25 to <50th: 1.16 (0.84, 1.61)
                                                                                                                50to<75th:0.86 0.63, 1.19
                                                                                                                75to<95th:0.98 0.71,1.34
                                                                                                                > 95th: 0.68 (0.38, 1.21)
                                                                                                                Continuous: 0.92 (0.81,1.05)
                                                                                                                3rd Trimester
                                                                                                                <25th:1.00
                                                                                                                25to<50th:0.77(0.55, 1.07)
                                                                                                                50to<75th:1.12 0.76, 1.66
                                                                                                                75to<95th:0.93 0.65,1.31
                                                                                                                > 95th: 0.90 (0.55, 1.47)
                 	Continuous: 0.96 (0.80,1.15)
    December 2009                                                    E-457
    

    -------
                  Study
           Design & Methods
                                                 Concentrations1
        Effect Estimates (95% Cl)
    Reference: Mannes et al.(2005,
    0878951
    
    Period of Study: Jan 1998-Dec 2000
    
    Location: Metropolitan Sydney,
    Australia
    Outcome: Risk of SGA and birth weight  Pollutant: PM10
    
                                         Averaging Time: 24 h
    
                                         Mean (SD): 16.8 (7.1)
    
                                         25th: 12.3
    
                                         60th(Median): 15.7
    
                                         76th: 19.9
    
                                         Range (Min, Max): (3.8-104.0)
    
                                         Monitoring Stations: up to 14
    Age Groups: All singleton births >20
    wk and 2 400 grams birth weight and
    maternal all ages
    
    Study Design: Cross-sectional
    
    N: 138,056 singleton births
    
    Statistical Analyses: Logistic and
    linear regression models
                                         Covariates: Sex of child, maternal age,
                                         gestational age, maternal smoking,
                                         gestational age at first antenatal visit,
                                         maternal indigenous status, whether
                                         first pregnancy, season of birth,
                                         socioeconomic status
    
                                         Season: All seasons
    
                                         Included as covariate
    
                                         Dose-response Investigated? No
    
                                         Statistical Package: SASv8.02
                                         Copollutants (correlations):
                                         CO: r = 0.26
    
                                         N02:r = 0.47
    
                                         03:r = 0.52
    
                                         PM25:r = 0.81
    PM Increment: 1 pg/m
    
    Risk of SGA
    All births
    One month before birth:
    OR = 1.01 (1.00-1.03)
    Third trimester: OR = 1.00 (0.99-1.013)
    Second trimester:
    OR = 1.01 (1.00-1.04)
    First trimester: OR = 1.00 (0.98-1.02)
    5 km births
    One month before birth: OR = 1.00
    (0.99-1.02)
    Third trimester: OR = 1.01 (0.99-1.02)
    Second trimester:
    OR = 1.02 (1.01-1.03)
    First trimester: OR = 1.01 (0.99-1.02)
    Change in birth weight
    All births
    One month before birth:
    IS = -1.21 (-2.31--0.11)
    Third trimester: IS = -0.95 (-2.30-0.40)
    Second trimester:
    IS = -2.05 (-3.36--0.74)
    First trimesters = -0.14 (-1.37-1.09)
    5 km births
    One month before birth:
    IS = -2.98(-4.25--1.71)
    Third trimester: IS = -3.84 (-5.35- -2.33)
    Second trimester:
    IS = -4.28 (-5.79--2.77)
    First trimesters = -2.57 (-4.04--1.10)
    Key second trimester findings
    Single pollutant model:
    IS = -4.28 (-5.79--2.77)
    2 pollutant (PM10 and CO):
    IS = -3.72 (-6.29--1.15)
    2 pollutant (PM10 and N02):
    IS = -2.65 (-4.32--0.98)
    2 pollutant (PM,0 and 03):
    IS = -5.47 (-7.06--3.88)
    4 pollutant (PM10, N02,  CO and 03):
    IS = -3.27 (-7.05-0.51)
    Controlling for exposures in other
    pregnancy periods:
    IS = -3.03(-4.85--1.21)	
    Reference: Pereira et al. (1998,
    0072641
    
    Period of Study: Jan 1991-Dec 1992
    
    Location: Sao Paulo, Brazil
    
    Notes: Paper does not focus on PM as
    a pollutant of interest.
    Outcome: Intrauterine mortality
    (fetuses over 28 wk of pregnancy)
    
    Study Design: Time-series
    
    N: 730 days with PM measures
    
    Statistical Analyses: Poisson
    regression
    
    Covariates: Season, day of the week
    and weather (temperature and  relative
    humidity)
    
    Season: Assessed by including 24
    indicator variables for month and yr
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    
    Lags Considered: Paper focuses on
    other pollutants (lags for PM not
    reported)
                                         Pollutant: PM,0
    
                                         Averaging Time: 24 h mean
    
                                         Mean (SD): 65.04 (27.28)
    
                                         Range (Min, Max): (14.80,192.80)
    
                                         Monitoring Stations: 13 (avgd to
                                         provide city-wide pollutant level)
    
                                         Copollutants (correlation):
                                         N02(r = 0.45)
    
                                         S02(r = 0.74)
    
                                         CO (r = 0.41)
    
                                         03(r = 0.25)
    PM Increment: NR (reported only
    regression coefficients for PM)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Regression coefficients (standard
    errors) for pollutants when considered
    separately and simultaneously in the
    completed model:
    
    Separately: 0.0008 (0.0006)
    
    Simultaneously: -0.0005 (0.0010)
    December 2009
                                     E-458
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ritz et al. (2000, 0120681
    
    Period of Study: 1989-1993
    
    Location: Southern California
    Outcome: Preterm birth (treated
    dichotomously as birth at <37 wk
    gestation
    
    Also analyzed continuously)
    
    Age Groups: Infants (born vaginally
    between 26-44 wk of gestation)
    
    Study Design: Cross-sectional
    
    N: 97,158 births
    
    Statistical Analyses: Logistic and
    linear regression
    
    Covariates: Maternal age, race,
    education, parity, interval since the
    previous live birth, access to prenatal
    care, infant sex, previous low weight or
    preterm births, smoking (reported  as
    "pregnancy complications")
    
    To examine effect modification, authors
    conducted stratified analysis by region,
    birth and conception seasons, maternal
    age, race, education, and  infant gender
    
    Season: Some models included
    season of birth or conception
    
    Also assessed as effect modifier in
    stratified analyses
    
    Dose-response Investigated?
    Examined adequacy of linear or log-
    linear relation using indicator terms for
    pollutant-avg quartiles
    
    Results presented in Fig 2 (dose-
    response demonstrated for last 6 wk
    exposure period)
    
    Statistical Package: NR
    Pollutant: PM,0
    
    Averaging Time: 24-h avg at 6 day
    intervals
    
    avgd pollutant measures for 1, 2, 4, 6,
    8,12, and 26 wk before birth and the
    whole pregnancy period
    
    Mean (SD): 6 wk before birth: 47.5
    (15.0)
    
    1st month of pregnancy: 49.3 (16.9)
    
    Range (Min, Max): 6 wk before birth:
    12.3-152.3
    
    1st month of pregnancy: 9.5-178.8
    
    Monitoring Stations: 17 stations (PM
    measured at only 8 stations)
    
    Copollutants (correlations):
    
    6 wk before birth:
    CO (r = 0.43)
    
    N02(r = 0.74)
    
    03(r = 0.20)
    
    1st month of pregnancy:
    CO (r = 0.37)
    
    N02(r = 0.71)
    
    03(r = 0.23)
    
    Notes: Avgd pollutant measures taken
    at the air monitoring station closest to
    the residence
    PM Increment: 50 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    All 8 stations
    6 wk before birth
    Crude: 1.20 (1.09,1.33)
    2 exposure periods: 1.18 (1.07,1.31)
    Other riskfactors: 1.15 (1.04,1.26)
    Other RFs plus season: 1.15(1.03,
    1.29)
    Multipollutant model: 1.19 (1.01,1.40)
    1st month of pregnancy
    Crude: 1.16 (1.06,1.26)
    2 exposure periods: 1.13 (1.04,1.24)
    Other riskfactors: 1.09 (1.00,1.19)
    Other RFs plus season: 1.09 (0.99,
    1.20)
    Multipollutant model: 1.12 (0.97,1.29)
    Coastal stations only
    6 wk before birth
    Crude: 1.22 (1.00,1.49)
    2 exposure periods: 1.28 (1.04,1.56)
    Other risk factors: 1.13 (0.93,1.38)
    Other RFs plus season: 1.18(0.92,
    1.51)
    Multipollutant model: 1.42 (097, 2.01)
    1st month of pregnancy
    Crude: 1.28 (1.06,1.54)
    2 exposure periods: 1.32 (1.09,1.59)
    Other risk factors: 1.17 (0.97,1.40)
    Other RFs plus season: 0.99 (0.79,
    1.24)
    Multipollutant model: 1.09(0.83,1.41)
    Inland stations only
    6 wk before birth
    Crude: 1.27 (1.12,1.44)
    2 exposure periods: 1.27 (1.11,1.44)
    Other riskfactors: 1.19 (1.05,1.35)
    Other RFs plus season: 1.27(1.10,
    1.48)
    Multipollutant model: 1.18 (0.97,1.43)
    1st month of pregnancy
    Crude: 1.16 (1.04,1.29)
    2 exposure periods: 1.16 (1.04,1.29)
    Other risk factors: 1.09 (0.98,1.21)
    Other RFs plus season: 1.09 (0.97,
    1.24)
    Multipollutant model: 1.11  (0.93,1.33)
    Crude estimates for last 6 wk
    exposure by season
    Fall: 1.08 (0.88, 1.31)
    Summer: 1.06  (0.87,1.29)
    Winter: 1.33  (1.07,1.65)
    Spring: 1.81  (1.41,2.31)
    Reduction in mean gestation length
    for each increase in PM10 during last
    6 wk before birth (linear regression
    analysis)
    Crude: 0.66 (±  0.24) days
    Adj: 0.90 (± 0.27) days
    Notes: Effect estimates remain stable
    when  excluding SGA or LBW children
    or when restricting preterm births to
    SGA or LBW children only (results not
    presented)
    December 2009
                                     E-459
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ritz, et al. (2002, 0232271
    
    Period of Study: 1987-1993
    
    Location: Southern California
    
    (Jul1990-Jul 1993 for Los Angeles,
    1989 for Riverside, 1988-1989 for San
    Bernardino, and 1987-1989 for Orange
    counties
    Outcome:
    1 Aortic defects
    2 Defects of the atrium and atrium
    Sepum
    3 Endocardial and mitral valve defects
    4 Pulmonary artery and valve defects
    5) Conotruncal defects including
    tetralogy of Fallot, transposition of great
    vessels, truncus arteriosus communis,
    double outlet right ventricle, and
    aorticopulmonary window
    and 6) Ventricular Sepal defects not
    included in the conotruncal category.
    Age Groups: All live born infants and
    fetal deaths diagnosed between 20 wk
    of gestation and 1 yr after birth
    
    Study Design: Case-control
    
    N: 10,649 infants and fetuses
    
    Statistical Analyses: Hierarchical (two-
    level) regression model,  polytomous
    logistic regression, linear model
    
    Covariates: Gender, no prenatal care,
    multiple births, no siblings, maternal
    race, maternal age,  maternal education,
    born before 1990, season of
    conception,
    
    Season: All
    
    Dose-response Investigated? Yes, for
    03 and CO, study found  a clear dose-
    response pattern for aortic Sepum and
    valve and ventricular Sepal defects and
    possibly for conotruncal  and pulmonary
    artery and valve defects
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: 24 h (every 6 days)
    
    PM Component: vehicle emissions
    
    Monitoring Stations: 11 (for PM10)
    
    Copollutants (correlations):
    CO: r = 0.32
    
    N02(NR)
    
    03 (NR)
    Notes: The authors did not observe
    consistently increased risks and dose-
    response patterns for PM10 after
    controlling for the effects of CO and 03
    on these cardiac defects. (Quantitative
    results not shown).
    December 2009
                                     E-460
    

    -------
                  Study
    Design & Methods
                                                 Concentrations1
                                             Effect Estimates (95% Cl)
    Reference: Ritz et al. (2006, 0898191
    
    Period of Study: 1989-2000
    
    Location: 389 South Coast Air Basin
    (SoCAB) zip codes
    Outcome: Total infant deaths during the
    first yr of life as well as all respiratory
    causes of death (ICD-9 codes 460-519,
    769, 770.4, 770.7, 770.8, and 770.9
    and ICD-10 codes JOO-J98, P22.0,
    P22.9, P27.1.P27.9, P28.0, P28.4,
    P28.5, and P28.9) and sudden infant
    death syndrome (SIDS) (ICD-9 code
    798.0 and  ICD-10 code R95).
    
    Age Groups: Infants 0-1 yr
    
    Study Design: Case-control
    
    N: 2,975,059 births and 19,664 infant
    deaths
    
    Cases, n = 13,146
    
    Controls, n = 151,015
    
    Statistical Analyses: Conditional
    logistic regression analysis
    
    Covariates: Risk factors available on
    birth and/or death certificates (maternal
    age, race/ethnicity, and education, level
    of prenatal care, infant gender, parity,
    birth country, and death season)
    
    Season: Death season (spring,
    summer, fall, winter)
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    Pollutant: PMi0
    
    Averaging Time: 24 h
    Mean (SD):
    2 wk before death: 46.2
    1 month before death: 46.3
    2 mo before death: 46.3
    6 mo before death: 46.3
    
    Range (Min, Max):
    2 wk before death: (21.0-83.5)
    1 month before death: (25.0-77.2)
    2 mo before death: (27.6-74.2)
    6 mo before death: (31.3-69.5)
    
    Monitoring Stations: maximum of 31
    
    Copollutants (correlation):
    2 wk before death
    CO: r = 0.33
    N02:r = 0.48
    03:r = 0.12
    1 month before death
    CO: r = 0.33
    N02:r = 0.48
    03:r = 0.12
    2 mo before death
    CO: r = 0.32
    N02:r = 0.48
    03:r = 0.12
    6 mo before death
    CO: r = 0.29
    N02:r = 0.44
    03:r = 0.16
                                                                      PM Increment: 10 pg/m
    
                                                                      Effect Estimate [Lower Cl, Upper Cl]:
    
                                                                      All-cause death
                                                                      2 mo before death
                                                                      Single-pollutant model:
                                                                      <25th = 1.04 (1.01-1.06)
                                                                      25th-75th = 0.96 (0.89-1.04)
                                                                      >75th = 1.14 (1.03-1.27)
                                                                      Multiple-pollutant model:
                                                                      <25th = 1.02 (0.99-1.05)
                                                                      25th-75th = 0.92 (0.84-1.00)
                                                                      >75th = 1.07 (0.95-1.20)
                                                                      SIDS
                                                                      2 mo before death:
                                                                      Single-pollutant model:
                                                                      <25th = 1.03 (0.99-1.08)
                                                                      25th-75th = 0.94 (0.81-1.08)
                                                                      >75th = 1.13 (0.93-1.36)
                                                                      Multiple-pollutant model:
                                                                      <25th = 1.01 (0.95-1.07)
                                                                      25th-75th = 0.90 (0.76-1.06)
                                                                      >75th = 0.99 (0.80-1.24)
                                                                      Respiratory death
                                                                      2 wk before death
                                                                      Postneonatal deaths (28 days to 1 y)
                                                                      Single-pollutant model:
                                                                      <25th = 1.05 (1.01-1.10)
                                                                      25th-75th = 1.13 (1.01-1.10)
                                                                      >75th = 1.46 (1.13-1.88)
                                                                      Multiple-pollutant model:
                                                                      <25th = 1.04 (0.98-1.09)
                                                                      25th-75th = 1.09 (0.86-1.38)
                                                                      >75th = 1.40 (1.03-1.89)
                                                                      Postneonatal deaths (28 days to 3
                                                                      mo)
                                                                      Single-pollutant model:
                                                                      <25th = 1.01 (0.95-1.08)
                                                                      25th-75th = 1.16(0.82-1.63)
                                                                      >75th = 1.44 (0.96-2.17)
                                                                      Multiple-pollutant model:
                                                                      <25th = 1.00 (0.92-1.09)
                                                                      25th-75th = 0.97 (0.67-1.42)
                                                                      >75th = 1.23 (0.76-2.00)
                                                                      Post neonatal deaths (4-12 mo)
                                                                      Single-pollutant model:
                                                                      <25th = 1.12 (1.02-1.23)
                                                                      25th-75th = 1.08 (0.81-1.44)
                                                                      >75th = 1.41 (1.02-1.96)
                                                                      Multiple-pollutant model:
                                                                      <25th = 1.07 (1.00-1.15)
                                                                      25th-75th = 1.02 (0.75-1.40)
                                                                      >75th = 1.36 (0.92-2.01)	
    December 2009
                              E-461
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Rogers et al. (2006,
    0912321
    Period of Study: 1986-1988
    
    Location: Georgia, USA
    Outcome: VLBW
    
    Term, AGA, Preterm AGA, Preterm,
    SGA
    
    Age Groups: Newborns and their
    mothers (< 19 to >35-yr-old)
    
    Study Design: Case-control
    
    N: 325 infants (69 preterm SGA
    
    59 preterm AGA
    
    197 term AGA) and their mothers
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Maternal age, maternal
    race, maternal education, active and
    passive smoking, birth season,
    prepregnancy weight, pregnancy weight
    gain, maternal toxemia, anemia,
    asthma
    
    Dose-response Investigated? Yes,
    used
    
    Statistical Package: SUDAAN
    
    Cochran-Armitage test for trend to
    determine whether the observed
    proportions of cases  and controls
    differed in a linear manner across
    exposure categories.
    Pollutant: PM,0
    
    Averaging Time: annual
    
    Preterm SGA:
    
    60th(Median): 3.38
    
    Preterm AGA:
    
    60th(Median): 7.84
    
    Term AGA:
    
    60th(Median): 3.23
    
    Monitoring Stations: NR
    
    Percent Mothers Residing In County
    With Industrial Point Source
    Preterm SGA: 60.9%
    Preterm AGA: 79.7%
    Term AGA: 60.4%
    Percent Mothers Residing In PM10
    Quartile (based on environmental
    transport model)
    Preterm SGA
    1st quartile(<1.48): 31.9%
    2nd quartile (1.48-3.74): 18.8%
    3rd quartile (3.75-15.07): 26.1%
    4th quartile (>15.07): 23.2%
    Preterm AGA
    1st quartile (<1.48): 16.9%
    2nd quartile (1.48-3.74): 22.1%
    3rd quartile (3.75-15.07): 28.8%
    4th quartile (>15.07): 32.2%
    Term AGA
    1st quartile (<1.48): 24.7%
    2nd quartile (1.48-3.74): 28.4%
    3rd quartile (3.75-15.07): 27.9%
    4th quartile (>15.07): 19.3%
    PM Increment: Quartile
    
    Notes: Statistically significant increases
    in the odds of VLBW and preterm AGA
    births are associated with living in a
    county with a PMi0 point source.
    Preterm AGA births are also associated
    with living in an area with very high (4th
    quartile) estimated PM10 exposure.
    Delivery of VLBW vs. Term AGA infant
    County with point source
    2.54 [1.46, 4.22]
    PM10 quartile
    1st quartile: reference
    2nd quartile:
    0.81  [0.42, 1.55]
    3rd quartile:
    0.85 [0.45, 1.16]
    4th quartile:
    1.94 [0.98, 3.83]
    Delivery of Preterm AGA vs. Term AGA
    infant
    County with point source
    4.31  [1.88:9.87]
    PM10 quartile
    1st quartile: reference
    2nd quartile:
    1.56 [0.56: 4.35]
    3rd quartile:
    1.19 [0.44: 3.23]
    4th quartile:
    3.68 [1.44: 9.44]
    Delivery of Preterm AGA vs. Preterm
    SGA infant
    County with point source
    2.07 [0.83: 5.16]
    PM10 quartile
    1st quartile: reference
    2nd quartile:
    1.96 [0.59: 6.43]
    3rd quartile:
    2.10 [0.66: 6.73]
    4th quartile:
    2.58 [0.78: 8.51]	
    December 2009
                                     E-462
    

    -------
    Study
    Reference: Romieu et al. (2004,
    0930741
    Period of Study: 1997-2001
    Location: Ciudad Juarez, Mexico
    
    
    
    
    
    
    
    
    
    Design & Methods
    Outcome: Respiratory-related infant
    mortality ICD9 (460-51 9)
    ICD10(JOO-J99)
    Age Groups: 1 month to 1 yr
    Study Design: Case crossover
    
    N: 216 respiratory-related deaths
    N = 412 other causes and N = 628 total
    deaths
    Statistical Analyses: The acute effects
    of air pollution was modeled on both
    total and respiratory-related mortality as
    a function of the pollution levels on the
    same day and preceding days and over
    2- and 3-day avg before the date of
    death. Case-crossover with semi-
    symmetric bidirectional referent
    selection was the approach used. Data
    were stratified by day of the week and
    calendar month. Data were analyzed
    with conditional logistic regression.
    Second and third polynomial distributed
    lag models were used to study lag
    structure. BIC was used to determine
    Igq ignqth
    
    Covariate: Temperature, season
    Concentrations1
    Pollutant: PM,0
    Averaging Time: 24 h
    
    Mean (SD):
    1997: 33.04 (20.67) pg/m3
    1998: 35.25 (17.32) pg/m3
    
    1999: 45.92 (28.69) pg/m3
    2000: 43.38 (23.77) pg/m3
    2001: 39.46 (29.43) pg/m3
    Monitoring Stations: 5 stations in
    Ciudad Juarez
    2 stations in El Paso (close to U.S.-
    Mexico border)
    Copollutant (correlation): 0; r = 0.01
    Notes: Ciudad Juarez monitors
    measured PM10 every 6 days while El
    Paso monitors measured on a daily
    basis.
    
    
    
    
    Effect Estimates (95% Cl)
    PM Increment: 20 pg/m3
    RR Estimate [Lower Cl, Upper Cl]
    lag:
    Total mortality:
    OR = 1.02 (0.94-1. 11) lag 1
    OR = 1.03 (0.95-1. 12) lag 2
    OR = 1.03 (0.94-1.1 3 ac2
    OR = 1.04 (0.95-1.1 5) ac3
    Respiratory mortality
    OR = 0.95 (0.83-1. 09) lag 1
    OR = 1.04 (0.91 -1.1 9 lag 2
    OR = 0.98 (0.81 -1.1 9 ac2
    OR = 0.97 (0.74-1. 26) ac3
    Higher SES
    OR = 0.82 (0.59, 1.1 4) lag 1
    OR = 1.08 (0.84, 1.40) lag 2
    OR = 0.89 (0.58, 1.35 ac2
    OR = 0.97 (0.52, 1.82 ac3
    Medium SES
    OR = 0.99 (0.79, 1.27) lag 1
    OR = 1.11 (0.86, 1.43) lag 2
    OR = 1.03 (0.73, 1.45)ac2
    OR = 1.1 7 (0.72, 1.90)ac3
    Lower SES
    OR = 1.61 (0.97-2.66) lag 1
    OR = 1.07 (0.65, 1.75) lag 2
    OR = 2. 56 (1.06-6.1 7) ac2
    OR = 1.76 (0.59, 5.23) ac3
    Notes:
                                        Dose-response Investigated? Yes
    
                                        Statistical Package: STATA7.0
    
                                        Lags Considered: 1-15 days
                                                                             ac2 and ac3 represent cumulative PMi0
                                                                             ambient levels over 2 or 3 days before
                                                                             death.
    Reference: Sagiv et al. (2005, 0874681
    
    Period of Study: Jan  1997-Dec 2001
    
    Location: Allegheny county, Beaver
    county, Lackawanna county,
    Philadelphia county, Pennsylvania,
    U.S.A.
    Outcome: Preterm birth (<36 wk)
    
    Age Groups: Babies born between 20
    and 44 wk
    
    Study Design: Time series
    
    N: 3704 observation days, 187,997
    births
    
    Statistical Analyses:  Poisson
    regression
    
    Multivariable mixed-effects model with a
    random intercept for each county to
    incorporate count-level information.
    
    Covariates: Temperature, dew point
    temperature, mean 6-week level of
    copollutants (CO, N02, and S02), long-
    term preterm birth trends
    
    Season: All
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    
    Lags Considered: 1,2, 3, 4, 5, 6, 7
    Pollutant: PM10
    
    Averaging Time: Daily used to
    calculate 6-week period
    
    Mean (SD): 6-week period
    
    27.1  (8.3)
    
    Daily
    
    25.3(14.6)
    
    Percentiles: 6-week period
    
    60th (Median): 26.0 Daily
    
    60th (Median): 21.6
    
    Range (Min, Max): 6-week period: 8.7,
    68.9
    
    Daily: 2.0,156.3
    
    Monitoring Stations: NR
    
    Copollutant (correlation): Daily
    PMio-dailyS02:r = 0.46
    
    Also considered CO, N02 and 03 as
    copollutants.
    PM Increment: 1) 50 pg/m  2) Quartiles
    (first quartile is the reference)
    Exposure period: 6 wk before birth
    Per 50 pg/m3:1.07 (0.98,1.18)
    2nd quartile: 1.00 (0.95,1.05)
    3rd quartile: 1.04 (0.99,1.09)
    4th quartile: 1.03 (0.98,1.08)
    Exposure period: 1-day acute time
    windows Per 50 pg/m   2-day lag: 1.10
    (1.00,1.21)
    
    5-day  lag:  1.07 (0.98,1.18)
    Notes: Within the article, authors
    provide a Fig 1 displaying a graph of
    the relative risk (RR) and 95%
    confidence i
    ntervals (Cl) for 1- to 7-day lags. While
    the authors report the 2- and 5-day lag
    RRs and 95% CIs in the text, the others
    are not specifically reported. However,
    the Fig shows the approximate RRs per
    50 pg/m3 as indicated below:
    1-day  lag:  1.05
    3-day  lag:  1.05
    4-day  lag:  1.00
    6-day  lag:  0.97
    7-day  lag:  1.03
    December 2009
                                     E-463
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: (Salam et al., 2005,
    0878851
    
    Period of Study: 1975-1987
    
    Location: Southern California
    Outcome: Birth weight
    
    Low birth weight (LBW
    
    <2500 g)
    
    Intrauterine growth retardation (IUGR)
    
    Age Groups: Children born full-term
    (between 37 and 44 wk)
    
    Study Design: Cohort study
    
    N: 3901 children
    
    Statistical Analyses: Linear mixed-
    effects
    
    Logistic regression
    
    Covariates: Maternal age, months
    since last live birth, parity, maternal
    smoking during pregnancy, SES, marital
    status at childbirth, gestational diabetes,
    child's sex, child's race/ethnicity, child's
    grade in school (4th,  7th, and 10th),
    Julian day of birth
    
    Season: All
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: Monthly
    Mean (SD):
    Entire pregnancy: 45.8 (12.9)
    First trimester: 46.6 (15.9)
    Second trimester: 45.4 (14.8)
    Third trimester: 45.4 (15.5)
    
    Monitoring Stations: 1 or 3 (See
    notes)
    
    Copollutant (correlation):
    Entire pregnancy
    PMio-03[10-6]:r = 0.54
    PMio-03[24h):r = 0.20
    PM10-N02:r = 0.55
    PMio-CO:r = 0.41
    First trimester
    PM10-03[10-6]:r = 0.54
    PMio-03[24h]:r = 0.34
    PMio-N02:r = 0.48
    PM10-CO:r = 0.29
    Second trimester
    PM10-03[10-6):r = 0.50
    PM10-03(24h):r = 0.27
    PMio-N02:r = 0.53
    PM10-CO:r = 0.35
    Third trimester
    PMio-03[10-6]:r = 0.52
    PMio-03[24h]:r = 0.31
    PM10-N02:r = 0.52
    PMio-CO:r = 0.37
    Notes: Exposure estimates were
    calculated by spatially interpolated
    monthly avg which were based off of
    three monitoring stations located within
    50 km of the ZIP code region of
    maternal birth residences.
    PM Increment: IQR (interquartile
    range)
    Outcome: birth weight (g)
    Single-pollutant model
    Entire pregnancy
    18 pg/m3: -19.9 (-43.6, 3.8)
    First trimester
    20 pg/m3: -3.0 (-22.7, 16.7)
    Second trimester
    19|jg/m3:-15.7(-36.1,4.7)
    Third trimester
    20|jg/m3:-21.7(-42.2to-1.1)
    Multipollutant model
    (Included 03
    (24 h) in model
    Third trimester exposure)
    20|jg/m3:-10.8(-31.8,10.2)
    Outcome: IUGR (ORs)
    Single-pollutant model
    Entire pregnancy
    18|jg/m3:1.1 (0.9,1.3)
    First trimester
    20|jg/m3:1.0(0.9,1.2)
    Second trimester
    19|jg/m3:1.0(0.9,1.2)
    Third trimester
    20|jg/m3:1.1 (0.9,1.3)
    Outcome: LBW
    Single-pollutant model
    Entire pregnancy
    18|jg/m3:1.3(0.8, 2.2)
    First trimester
    20|jg/m3:1.0(0.7,1.5)
    Second trimester
    19|jg/m3:1.2(0.8,1.7)
    Third trimester
    20|jg/m3:1.3(0.9,1.9)
    Notes: Numbers reported for birth
    weight outcome are the effects on birth
    weight outcome (the change in birth
    weight in grams) across the IQR (which
    vary depending on air pollutant and
    duration of exposure measurement).
    Reference: (Sokol et al, 2006, 0985391 Outcome: Semen Quality
    
    Period of Study: Jan  1996-Dec 1998   Study Design: Panel
    
    Location: Los Angeles, California       Statistical Analysis: Univariate and
                                        Multivariate Regression
    
                                        Statistical Package: SAS
    
                                        Age Groups: Males ranging 19-35 in
                                        age
                                        Pollutant: PM10
    
                                        Averaging Time: 0-9d, 10-14d and 70-
                                        90d
    
                                        Mean (SD) Unit: 35.74 + 13.83 pg/m3
    
                                        Copollutant (correlation):
                                        03, N02, CO
                                        PM10 specific results are given in Fig 3-.
                                        PM10 was not significantly correlated
                                        with sperm quality.
    Reference: (Suh et al, 2007,1570281
    
    Period of Study: 2001-2004
    
    Location: Seoul, Korea
    Outcome: Birth weight
    
    Age Groups: Prenatal follow-up for
    newborns
    
    Study Design: based prospective
    cohort study
    
    N: 199 pregnant mothers
    
    Statistical Analyses: ANCOVA,
    generalized linear models
    
    Covariates: infant's sex, maternal age,
    maternal and paternal education, parity,
    presence of illness during pregnancy,
    delivery month, gestational age
    (squared)
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: 24-h
    Mean (SD): 1st trimester: 76.41
    2nd trimester: 77.84 (31.63)
    3rd trimester: 95.61 (26.15)
    
    Percentiles: 1st trimester
    26th: 55.28
    60th(Median):71.09
    76th: 92.38
    2nd trimester
    26th: 48.65
    60th(Median): 72.36
    76th: 108.00
    3rd trimester
    26th:77.10
    60th(Median): 96.35
    76th: 116.68
    
    Range (Min, Max):
    1st trimester (21.00,151.65)
    PM Increment: Trimester Ł 90th
    percentile compared to <90thpercentile
    
    Least-square (ANCOVA) mean (SE)
    
    All Genotypes
    1st trimester
    <90th, N(%):
    158 (90.3%): 3253 (37)
    > 90th percentile, N(%): 17 (9.7%):
    2841 (145)
    P-Value for mean birth weight for > 90th
    percentile PM10 vs. for <90th percentile
    PM10
    Adjusted: 0.009
    Adjusted, with CO: 0.041
    Adjusted, with N02: 0.092
    Adjusted, with S02: 0.012
    2nd trimester
    <90th percentile, N(%):
    153 (89.5%): 3253 (39)
    > 90th percentile, N(%):
    18 (10.5%): 3026 (157)	
    December 2009
                                     E-464
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                             2nd trimester (31.45,139.13)
                                                                             3rd trimester (23.45,172.75)
    
                                                                             Monitoring Stations: 27
    
                                                                             Copollutant:
                                                                             CO
                                                                             S02
                                                                             N02
                                                                      P-Value for mean birth weight for 2 90th
                                                                      percentile PMi0 vs. for <90th percentile
                                                                      PM10
                                                                      Adjusted: 0.177
                                                                      Adjusted, with CO: 0.203
                                                                      Adjusted, with N02: 0.151
                                                                      Adjusted, with S02: 0.151
                                                                      3rd trimester
                                                                      <90th percentile, N(%):
                                                                      162 (90.5%):  3226 (38)
                                                                      > 90th percentile, N(%): 17 (9.5%):
                                                                      3122(140)
                                                                      P-Value for mean birth weight for > 90th
                                                                      percentile PMi0 vs. for <90th percentile
                                                                      PM10
                                                                      Adjusted: 0.487
                                                                      Adjusted, with CO: 0.748
                                                                      Adjusted, with N02: 0.420
                                                                      Adjusted, with S02: 0.466
                                                                      Genotype Mspl TT
                                                                      1st trimester
                                                                      <90th percentile, N(%): 60 (34.3%):
                                                                      3350 (64)
                                                                      > 90th percentile, N(%): 5 (2.9%): 3001
                                                                      (229)
                                                                      P-Value for mean birth weight for 2 90th
                                                                      percentile PM10 vs. for <90th percentile
                                                                      PM10
                                                                      Adjusted: 0.147
                                                                      Adjusted, with CO: 0.186
                                                                      Adjusted, with N02: 0.430
                                                                      Adjusted, with S02: 0.155
                                                                      2nd trimester
                                                                      <90th percentile, N(%): 59 (34.5%):
                                                                      3335 (66)
                                                                      > 90th percentile, N(%): 6 (3.5%): 3281
                                                                      (249)
                                                                      P-Value for mean birth weight for
                                                                      > 90th percentile PM,o vs. for <90th
                                                                      percentile PM10
                                                                      Adjusted: 0.833
                                                                      Adjusted, with CO: 0.833
                                                                      Adjusted, with N02: 0.778
                                                                      Adjusted, with S02: 0.806
                                                                      3rd trimester
                                                                      <90th percentile, N(%): 61 (34.1%):
                                                                      3327 (65)
                                                                      > 90th percentile, N(%): 6 (3.4%): 3227
                                                                      (300)
                                                                      p-Value for mean birth weight for
                                                                      > 90th percentile PM,o vs. for <90th
                                                                      percentile PM10
                                                                      Adjusted: 0.749
                                                                      Adjusted, with CO: 0.980
                                                                      Adjusted, with N02: 0.635
                                                                      Adjusted, with S02: 0.687
                                                                      Genotype Mspl TC/CC
                                                                      1st trimester
                                                                      <90th percentile, N(%): 98 (56.0%):
                                                                      3193 (48)
                                                                      > 90th percentile, N(%): 12(6.9%):
                                                                      2799(169)
                                                                      P-Value for mean birth weight for
                                                                      > 90th percentile PM,0 vs. for <90th
                                                                      percentile PMi0
                                                                      Adjusted: 0.033
                                                                      Adjusted, with CO: 0.073
                                                                      Adjusted, with N02: 0.150
                                                                      Adjusted, with S02: 0.036
                                                                      2nd trimester
                                                                      <90th percentile, N(%): 94 (55.0%):
                                                                      3200 (52)
                                                                      > 90th percentile, N(%): 12 (7.0%):
                                                                      2933(176)
                                                                      P-Value for mean birth weight for
                                                                      > 90th percentile PM,0 vs. for <90th
                                                                      percentile PMi0
                                                                      Adjusted: 0.161	
    December 2009
                             E-465
    

    -------
                  Study                        Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                 Adjusted, with CO: 0.172
                                                                                                                 Adjusted, with N02: 0.152
                                                                                                                 Adjusted, with S02: 0.158
                                                                                                                 3rd trimester
                                                                                                                 <90th percentile, N(%): 101 (56.4%):
                                                                                                                 3165(49)
                                                                                                                 > 90th percentile, N(%): 11 (6.2%):
                                                                                                                 3087(147)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PMi0 vs. for <90th
                                                                                                                 percentile PMio
                                                                                                                 Adjusted: 0.626
                                                                                                                 Adjusted, with CO: 0.978
                                                                                                                 Adjusted, with N02: 0.551
                                                                                                                 Adjusted, with S02: 0.614
                                                                                                                 Genotype Ncol  llelle
                                                                                                                 1st trimester
                                                                                                                 <90th percentile, N(%): 87 (49.7%):
                                                                                                                 3244 (52)
                                                                                                                 > 90th percentile, N(%): 7 (4.0%): 2983
                                                                                                                 (232)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM10 vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.289
                                                                                                                 Adjusted, with CO: 0.344
                                                                                                                 Adjusted, with N02: 0.641
                                                                                                                 Adjusted, with S02: 0.293
                                                                                                                 2nd trimester
                                                                                                                 <90th percentile, N(%): 82 (48.0%):
                                                                                                                 3243 (55)
                                                                                                                 > 90th percentile, N(%): 11 (6.4%):
                                                                                                                 3185(207)
                                                                                                                 p-Value for mean birth weight for
                                                                                                                 > 90th percentile PM10 vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.790
                                                                                                                 Adjusted, with CO: 0.783
                                                                                                                 Adjusted, with N02: 0.707
                                                                                                                 Adjusted, with S02: 0.733
                                                                                                                 3rd trimester
                                                                                                                 <90th percentile, N(%): 90 (50.3%):
                                                                                                                 3239 (53)
                                                                                                                 > 90th percentile, N(%): 9 (5.0%): 2944
                                                                                                                 (198)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM10 vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.161
                                                                                                                 Adjusted, with CO: 0.279
                                                                                                                 Adjusted, with N02: 0.134
                                                                                                                 Adjusted, with S02: 0.150
                                                                                                                 Genotype Ncol  HeVal/ValVal
                                                                                                                 1st trimester
                                                                                                                 <90th percentile, N(%): 71 (40.6%):
                                                                                                                 3262 (56)
                                                                                                                 > 90th percentile, N(%): 10(5.7%):
                                                                                                                 2773(171)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,o vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.009
                                                                                                                 Adjusted, with CO: 0.031
                                                                                                                 Adjusted, with N02: 0.058
                                                                                                                 Adjusted, with S02: 0.010
                                                                                                                 2nd trimester
                                                                                                                 <90th percentile, N(%): 71 (41.5%):
                                                                                                                 3264(61)
                                                                                                                 > 90th percentile, N(%): 7 (4.1%): 2862
                                                                                                                 (208)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,o vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.076
                                                                                                                 Adjusted, with CO: 0.093
                                                                                                                 Adjusted, with N02: 0.063
                                                                                                                 Adjusted, with S02: 0.061
                                                                                                                 3rd trimester
    December 2009                                                    E-466
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                 <90th percentile, N(%): 72 (40.2%):
                                                                                                                 3207 (58)
                                                                                                                 > 90th percentile, N(%): 8 (4.5%): 3262
                                                                                                                 (180)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PMi0 vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.777
                                                                                                                 Adjusted, with CO: 0.607
                                                                                                                 Adjusted, with N02: 0.843
                                                                                                                 Adjusted, with S02: 0.791	
    Reference: Tsai et al. (2006, 0907091
    
    Period of Study: 1994-2000
    
    Location: Kaohsiung, Taiwan
    Outcome: Post neonatal mortality
    
    Age Groups: Infants more than 27
    days and less than 1 yr
    
    Study Design: Case-crossover study
    
    N: 207 deaths
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature, humidity
    
    Dose-response Investigated? No
    Pollutant: PM,0
    
    Averaging Time: 24 h
    
    Mean(SD):81.45|jg/m3
    
    Percentiles: 26th: 44.50
    
    60th(Median): 79.20
    
    76th:111.50
    
    Range (Mm, Max): (20.50-232.00)
    
    Monitoring Stations: 6
    PM Increment: 67.00 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    OR = 1.040 (0.340-3.177)
    
    Note: Air pollution levels at the dates of
    infant death were compared with air
    pollution levels 1 week before and  1
    week after death
    
    A cumulative lag up to 2 previous days
    was used to assign exposure.
    
    
    
    
    Reference: Wilhelm and Ritz (2005,
    088668)
    Period of Study: 1994-2000
    Location: Los Angeles County,
    California, U.S.
    
    
    
    
    
    Statistical Package: SAS, version 8.2
    
    
    
    Outcome: Term low birth weight (LBW)
    (<2500gat>37completedwk
    gestation), Vaginal birth <37 completed
    wk gestation
    Age Groups: LBW: 2 37 completed wk
    Preterm births: <37 completed wk
    Study Design: Cross-sectional
    N: For LBW: 136,134
    Forpreterm birth:
    106,483
    Copollutant:
    S02
    N02
    CO
    03
    Pollutant: PM,0
    Averaging Time:
    24 h (every 6 days)
    Entire pregnancy
    Trimesters of pregnancy
    Months of pregnancy
    6 wk before birth
    Mean (SD):
    First trimester: 42.2
    Third trimester: 41. 5
    6 wk before birth: 39.1
    Range (Min, Max):
    
    
    
    
    PM Increment:
    1)10|jg/m3
    2) 3 levels:
    a) <25 percentile (reference)
    b) 25%-75 percentile
    c) > 75 percentile
    Incidence of LBW (third trimester
    exposure)
    <32.8|jg/m3:2.0(1.8, 2.2)
    32.8to<43.4|jg/m3:2.0(1.9, 2.1)
    > 43.4 pg/m3: 2.2 (2.0, 2.4)
    
    Incidence of preterm birth (first
    trimester exposure)
                                        Statistical Analyses: Logistic
                                        regression
    
                                        Covariates: Maternal age, maternal
                                        race, maternal education, parity, interval
                                        since previous live birth, level of
                                        prenatal care, infant sex, previous LBW
                                        or preterm infant, birth season, other
                                        pollutants (CO, N02, 03, PM10),
                                        gestational age (in birth weight analysis)
    
                                        Dose-response Investigated? Yes
    
                                        Statistical Package: NR
                                         First trimester: 26.3, 77.4
                                         Third trimester: 25.7, 74.6
                                         6 wk before birth: 13.0, 103.7
    
                                         Monitoring Stations:
                                         Zip-code-level analysis: 8
                                         Address-level analysis: 6
    
                                         Copollutant (correlation):
                                         First trimester:
                                         PM,o-CO:r = 0.12
                                         PM10-N02:r = 0.29
                                         PMio-03:r = -0.01
                                         PMio-PM25:r = 0.43
                                         Third trimester:
                                         PMio-CO:r = 0.32
                                         PMio-N02:r = 0.45
                                         PMio-03:r = -0.08
                                         PMio-PM25:r = 0.52
                                         6 wk before birth:
                                         PM10-CO:r = 0.36
                                         PM,o-N02:r = 0.49
                                         PMio-03:r = -0.16
                                         PM10-PM25:r = 0.60
                                         <32.9 pg/rri : 8.7 (8.3, 9.2)
                                         32.9to<43.9|jg/m3:8.8(8.5, 9.1)
                                         > 43.9 pg/m3: 8.6 (8.1, 9.0)
    
                                         Incidence of preterm birth (6 wk
                                         before birth exposure)
                                         <31.8|jg/m3:8.8(8.4, 9.3)
                                         31.8to<44.1  pg/m3:8.6 (8.3, 8.9)
                                         a44.1  pg/m3: 8.8 (8.4, 9.2)
    
                                         Outcome: LBW
                                         Exposure Period: Third trimester
                                         Address-level analysis:
                                         Single-pollutant model:
                                         Distance < 1 mile
                                         Per 10 pg/m3:1.22 (1.05,1.41)
                                         33.4 to <44.7|jg/m3:1.08 (0.76, 1.52)
                                         > 44.7 pg/m3:1.48 (1.00, 2.19)
                                         Multipollutant model:
                                         Distance Ł 1 mile
                                         Per 10 pg/m3:1.36 (1.12,1.65)
                                         33.4to<44.7|jg/m3:1.16 (0.77, 1.74)
                                         > 44.7 pg/m3:1.58 (0.95, 2.62)
                                         Single-pollutant model:
                                         1  44.7 pg/m3: 0.96 (0.78, 1.18)
                                         Multipollutant model:
                                         1  44.7 |jg/m3:1.02 (0.79, 1.32)
    December 2009
                                     E-467
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
                                                                                                                   Single-pollutant model:
                                                                                                                   2  45.0 pg/m3:1.08 (0.97, 1.20)
                                                                                                                   Multipollutant model:
                                                                                                                   2  45.0 pg/m3:1.06 (0.93,1.21)
    
                                                                                                                   Zip-code-level analysis
                                                                                                                   Single-pollutant model:
                                                                                                                   Per 10 pg/m3:1.03 (0.97,1.09)
                                                                                                                   33.2 to <43.6|jg/m3:0.98 (0.86, 1.11)
                                                                                                                   > 43.6 pg/m3:1.03 (0.88, 1.21)
                                                                                                                   Multipollutant model:
                                                                                                                   Per 10 pg/m3:1.07 (0.99,1.15)
                                                                                                                   33.2 to <43.6|jg/m3: 0.97 (0.85, 1.12)
                                                                                                                   > 43.6 pg/m3:1.09 (0.90,1.31)
    
                                                                                                                   Outcome: LEW
                                                                                                                   Exposure Period: Entire pregnancy
                                                                                                                   period
                                                                                                                   Address-level analysis:
                                                                                                                   Multipollutant model:
                                                                                                                   Per 10 pg/m3:1.24 (0.91,1.70)
    
                                                                                                                   Outcome: Preterm Birth
                                                                                                                   Exposure Period: First trimester of
                                                                                                                   pregnancy
                                                                                                                   Address-level analysis:
                                                                                                                   Single-pollutant model:
                                                                                                                   Distance Ł 1 mile
                                                                                                                   Per 10 pg/m3:1.00 (0.93,1.09)
                                                                                                                   33.3to<45.1|jg/m3:1.07 (0.90, 1.26)
                                                                                                                   a45.1 fjg/m3:1.12 (0.91,1.38)
                                                                                                                   Multipollutant model:
                                                                                                                   Distance < 1 mile
                                                                                                                   Per 10 pg/m3:1.00 (0.90,1.12)
                                                                                                                   33.3to<45.1 |jg/m3:1.12(0.92, 1.36)
                                                                                                                   > 45.1 pg/m3:1.17 (0.90,1.50)
                                                                                                                   Single-pollutant model:
                                                                                                                   1  45.3 pg/m3:1.07 (0.97, 1.19)
                                                                                                                   Multipollutant model:
                                                                                                                   1  45.3 pg/m3:1.13 (1.00,1.27)
                                                                                                                   Single-pollutant model:
                                                                                                                   2  45.5 pg/m3:1.02 (0.96, 1.07)
                                                                                                                   Multipollutant model:
                                                                                                                   2  45.5 pg/m3: 0.94 (0.89, 1.01)
    
                                                                                                                   Zip-code-level analysis
                                                                                                                   Single-pollutant model:
                                                                                                                   Per 10 pg/m3: 0.99 (0.96,1.01)
                                                                                                                   33.3 to <44.2pg/m3:1.01 (0.95, 1.08)
                                                                                                                   > 44.2 pg/m3: 0.98 (0.90, 1.05)
                                                                                                                   Multipollutant model:
                                                                                                                   D^r ^ n i i^/fvi^1 n oo /n
                                                                                                                   Per 10 pg/rri : 0.99 (0.96,1.03)
                                                                                                                   33.3 to <44.2pg/m3:1.03 (0.97,
                                                                                                                   > 44.2 pg/m3:1.01 (0.92,1.11)
                                                                                                                   Outcome: Preterm birth
                                                                                                                   Exposure Period: 6 wk before birth
                                                                                                                   Address-level analysis:
                                                                                                                   Single-pollutant model:
                                                                                                                   Distance Ł 1 mile
    December 2009                                                     E-468
    

    -------
                  Study                       Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                   PeMOfjg/m°:1.02(0.95,1.10)
                                                                                                                   32.5 to <44.8|jg/m3:1.09 (0.92, 1.29)
                                                                                                                   > 44.8 pg/m3:1.12 (0.92, 1.37)
                                                                                                                   Multipollutant model:
                                                                                                                   Distance Ł 1 mile
                                                                                                                   Per 10 pg/m3:1.06 (0.97,1.16)
                                                                                                                   32.5 to <44.8|jg/m3:1.09 (0.90, 1.31)
                                                                                                                   > 44.8 pg/m3:1.17 (0.91,1.49)
                                                                                                                   Single-pollutant model:
                                                                                                                   1  45.3 pg/m3: 0.99 (0.89, 1.10)
                                                                                                                   Multipollutant model:
                                                                                                                   1  45.3 pg/m3:1.02 (0.91,1.16)
                                                                                                                   Single-pollutant model:
                                                                                                                   2  45.3 pg/m3: 0.98 (0.93, 1.03)
                                                                                                                   Multipollutant model:
                                                                                                                   2  45.3 pg/m3: 0.98 (0.92, 1.04)
    
                                                                                                                   Zip-code-level analysis
                                                                                                                   Single-pollutant model:
                                                                                                                   Per 10 pg/m3:1.02 (0.99,1.04)
                                                                                                                   32.1 to <44.3|jg/m3:1.01 (0.95, 1.07)
                                                                                                                   > 44.3 pg/m3:1.04 (0.96, 1.12)
                                                                                                                   Multipollutant model:
                                                                                                                   Per 10 pg/m3:1.02 (0.99,1.06)
                                                                                                                   32.1 to <44.3|jg/m3:1.02 (0.95, 1.09)
                                                                                                                   > 44.3 pg/m3:1.04 (0.95, 1.14)
                                                                                                                   Notes: multipollutant model adds
                                                                                                                   CO,N02, and 03 in addition to the main
                                                                                                                   pollutant of interest, PMi0.
    December 2009                                                     E-469
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Woodruff etal. (1997,
    0842711
    
    Period of Study: 1989-1991
    
    Location: 86 Metropolitan Statistical
    Areas in the U.S. (counties with
    populations less than 100,000 were
    excluded)
    Outcome: Postneonatal mortality
    (death of an infant between 1 month
    and 1 yr of age)
    1 All post neonatal deaths
    2 Normal birth weight (NBW, > 2500 g)
    SIDS deaths
    3 NBW respiratory deaths
    4 Low birth weight (LBW) respiratory
    death
    Respiratory deaths:  ICD9 codes 460-
    519
    
    SIDS:  ICD9 code 798.0
    
    Age Groups: Infants (1 month-1yrof
    age)
    
    Study Design: Cross-sectional
    
    N: 3,788,079 infants
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Maternal education,
    maternal race, parental marital status,
    maternal smoking during pregnancy
    
    Avg temperature during the first 2 mo of
    life
    
    Infant's month and yr of birth
    
    Assessed race as an effect modifier (p-
    val for interaction terms >0.2)
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    Pollutant: PM,0
    
    Averaging Time: Mean of 1st 2 mo of
    life
    
    analyzed as tertiles of exposure and as
    continuous exposure
    
    Mean (SD): 31.4 (7.8)
    
    Range (Min, Max):
    
    Overall: 11.9-68.8
    
    Low category: <28.0
    
    Medium category: 28.1-40.0
    
    High category: >40.0
    
    Monitoring Stations: NR
    PM Increment: 10 pg/m (for
    continuous exposure analysis)
    
    Adjusted ORs for cause-specific
    post neonatal mortality by pollution
    category (tertiles)
    All causes
    Low: Ref
    Medium: 1.05 (1.01,1.09)
    High: 1.10 (1.04,1.16)
    SIDS, NBW:
    Low: Ref
    Medium: 1.09 (1.01,1.17)
    High: 1.26 (1.14,1.39)
    Respiratory death, NBW:
    Low: Ref
    Medium: 1.08 (0.87,1.33)
    High: 1.40 (1.05,1.85)
    Respiratory death, LBW:
    Low: Ref
    Medium: 0.93 (0.73,1.18)
    High: 1.18 (0.86,1.61)
    All other causes:
    Low: Ref
    Medium: 1.03 (0.97,1.08)
    High: 0.97 (0.90, 1.04)
    
    Adjusted ORs for a continuous
    10 ug/m3 change in exposure
    All causes: 1.04 (1.02,1.07)
    SIDS, NBW:  1.12 (1.07, 1.17)
    Respiratory death
    NBW: 1.20 (1.06,  1.36)
    Respiratory death
    LBW: 1.05 (0.91, 1.22)
    All other causes: 1.00 (0.99,1.00)
    December 2009
                                    E-470
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Woodruff etal. (2008,
    0983861
    
    Period of Study: 1999-2002
    
    Location: U.S. counties with >250,000
    residents (96 counties)
    Outcome: Postneonatal deaths
    
    Respiratory mortality (ICD10: JOOO-99,
    plus bronchopulmonary dysplasia [BPD]
    P27.1)
    
    SIDS(ICD10:R95)
    
    Ill-defined causes (R99);
    
    All other deaths evaluated as a control
    category
    
    Age Groups: Infants aged >28 days
    and <1 yr
    
    Study Design: Cross-sectional
    
    N: 3,583,495 births (6,639 post
    neonatal deaths)
    
    Statistical Analyses: Logistic GEE
    (exchangeable correlation structure)
    
    Covariates: Maternal race/ethnicity,
    marital status, age,  education,
    primiparity, county-level poverty and per
    capita income levels, yr and month of
    birth dummy variables to account for
    time trend and seasonal effects, and
    region of the country
    
    Sensitivity analyses performed among
    only those mothers with smoking
    information  (adjustment for smoking
    had no effect on the estimates)
    
    Season: Adjusted for yr and month of
    birth dummy variables to account for
    time trend and seasonal effects
    
    Dose-response Investigated?
    Evaluated the appropriateness of a
    linear form from analysis based on
    quartiles of exposure and concluded
    that linear form was appropriate (data
    not shown)
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: Measured
    continuously for 24 h once every 6 days
    
    exposure assigned by calculating avg
    concentration of pollutant during first 2
    mo of life
    
    Median and IQR (25th-75th
    percentile): Survivors: 28.9 (23.3-34.4)
    
    All causes of death: 29.1 (23.9-34.5)
    
    Respiratory: 29.8 (24.3-36.5)
    
    SIDS: 28.6 (23.5-33.8)
    
    SIDS+ill-defined: 28.8 (23.9-33.9)
    
    Other causes: 29.2 (23.9-34.5)
    
    Percent! les: see above
    
    PM Component: Not assessed, but
    controlled for region of the country to
    account for PM composition variation
    
    Monitoring Stations: NR
    
    Copollutant (correlation):
    PM10
    
    PM25(r = 0.34)
    
    CO (r = 0.18)
    
    S02(r = 0.00)
    
    03(r = 0.20)
    
    Notes: Monthly avg calculated if there
    were at least 3 available measures for
    PM
    
    Assigned exposures using the avg
    concentration of the county of residence
    PM Increment: IQR (11 pg/rri)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    Adjusted ORs for single pollutant
    models
    
    All causes: 1.04 (0.99,1.10)
    
    Respiratory: 1.18 (1.06,1.31)
    
    SIDS: 1.02 (0.89, 1.16)
    
    Ill-defined + SIDS: 1.06 (0.97,1.16)
    
    Other causes: 1.02 (0.96,1.07)
    
    Adjusted ORs for multipollutant models
    (including CO, 03, S02)
    
    Respiratory: 1.16 (1.04,1.30)
    
    SIDS: 1.02 (0.90, 1.16)
    
    OR for deaths coded as BPD per
    increase in IQR: 1.19 (0.85,1.65)
    
    OR for respiratory post neonatal death
    stratified by birth weight
    
    NBW only: 1.19 (1.05,1.36)
    
    LBWonly: 1.12 (0.95,1.31)
    
    OR for respiratory deaths removing
    region of U.S. as  a confounding
    variable: 1.30 (1.04,1.61)
    
    OR for respiratory deaths assessing
    exposure as quartiles
    
    Highest  vs. Lowest quartile:
    1.31 (1.00,1.71)
    
    
    OR for respiratory deaths among only
    those deaths that occurred during the
    first 90 days (most closely matched
    exposure metric of the avg over the first
    2 mo of  life): 1.25 (1.06,1.47)
    Reference: (Suh et al, 2007,1570281
    
    Period of Study: 2001-2004
    
    Location: Seoul, Korea
    Outcome: Birth weight
    
    Age Groups: Prenatal follow-up for
    newborns
    
    Study Design: Based prospective
    cohort study
    
    N: 199 pregnant mothers
    
    Statistical Analyses: ANCOVA,
    generalized linear models
    
    Covariates: Infant's sex, maternal age,
    maternal  and paternal education, parity,
    presence of illness during pregnancy,
    delivery month, gestational age
    (squared)
    
    Dose-response Investigated? Yes
    
    Statistical Package: SAS
    Pollutant: PM,0
    
    Averaging Time: 24-h
    Mean (SD):
    1st trimester: 76.41 (28.80)
    2nd trimester: 77.84 (31.63)
    3rd trimester: 95.61 (26.15)
    Percent! les:
    1st trimester
    25th: 55.28
    60th(Median):71.09
    76th: 92.38
    2nd trimester
    26th: 48.65
    60th(Median): 72.36
    76th: 108.00
    3rd trimester
    26th:77.10
    60th(Median): 96.35
    76th: 116.68
    
    Range (Min, Max):
    1st trimester (21.00,151.65)
    2nd trimester (31.45,139.13)
    3rd trimester (23.45,172.75)
    
    Monitoring Stations: 27
    
    Copollutant:
    CO
    S02
    PM Increment: Trimester Ł 90th
    percentile compared to <90th percentile
    
    Least-square (ANCOVA)  mean (SE)
    All Genotypes
    1st trimester
    <90th percentile, N(%):
    158 (90.3%): 3253 (37)
    > 90th percentile, N(%): 17 (9.7%):
    2841 (145)
    P-Value for mean birth weight for
    > 90th percentile PM10 vs. for <90th
    percentile PM10
    Adjusted: 0.009
    Adjusted, with CO: 0.041
    Adjusted, with N02: 0.092
    Adjusted, with S02: 0.012
    2nd trimester
    <90th percentile, N(%):
    153 (89.5%): 3253 (39)
    > 90th percentile, N(%):
    18 (10.5%): 3026 (157)
    p-Value for mean birth weight for
    > 90th percentile PM10 vs. for <90th
    percentile PM10
    Adjusted: 0.177
    Adjusted, with CO: 0.203
    Adjusted, with N02: 0.151
    Adjusted, with S02: 0.151
    3rd trimester
    <90th percentile, N(%):	
    December 2009
                                     E-471
    

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                  Study                        Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                             ~162 (90.5%): 3226 (38)
                                                                                                                 > 90th percentile, N(%): 17 (9.5%):
                                                                                                                 3122(140)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM10 vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.487
                                                                                                                 Adjusted, with CO: 0.748
                                                                                                                 Adjusted, with N02: 0.420
                                                                                                                 Adjusted, with S02: 0.466
                                                                                                                 Genotype Mspl  TT
                                                                                                                 1st trimester
                                                                                                                 <90th percentile, N(%): 60 (34.3%):
                                                                                                                 3350 (64)
                                                                                                                 > 90th percentile, N(%): 5 (2.9%): 3001
                                                                                                                 (229)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,o vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.147
                                                                                                                 Adjusted, with CO: 0.186
                                                                                                                 Adjusted, with N02: 0.430
                                                                                                                 Adjusted, with S02: 0.155
                                                                                                                 2nd trimester
                                                                                                                 <90th percentile, N(%): 59 (34.5%):
                                                                                                                 3335 (66)
                                                                                                                 > 90th percentile, N(%): 6 (3.5%): 3281
                                                                                                                 (249)
                                                                                                                 p-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,o vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.833
                                                                                                                 Adjusted, with CO: 0.833
                                                                                                                 Adjusted, with N02: 0.778
                                                                                                                 Adjusted, with S02: 0.806
                                                                                                                 3rd trimester
                                                                                                                 <90th percentile, N(%): 61 (34.1%):
                                                                                                                 3327 (65)
                                                                                                                 > 90th percentile, N(%): 6 (3.4%): 3227
                                                                                                                 (300)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,o vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.749
                                                                                                                 Adjusted, with CO: 0.980
                                                                                                                 Adjusted, with N02: 0.635
                                                                                                                 Adjusted, with S02: 0.687
                                                                                                                 Genotype Mspl  TC/CC
                                                                                                                 1st trimester
                                                                                                                 <90th percentile, N(%): 98 (56.0%):
                                                                                                                 3193 (48)
                                                                                                                 > 90th percentile, N(%): 12(6.9%):
                                                                                                                 2799(169)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,0 vs. for <90th
                                                                                                                 percentile PMi0
                                                                                                                 Adjusted: 0.033
                                                                                                                 Adjusted, with CO: 0.073
                                                                                                                 Adjusted, with N02: 0.150
                                                                                                                 Adjusted, with S02: 0.036
                                                                                                                 2nd trimester
                                                                                                                 <90th percentile, N(%): 94 (55.0%):
                                                                                                                 3200 (52)
                                                                                                                 > 90th percentile, N(%): 12 (7.0%):
                                                                                                                 2933(176)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,0 vs. for <90th
                                                                                                                 percentile PMi0
                                                                                                                 Adjusted: 0.161
                                                                                                                 Adjusted, with CO: 0.172
                                                                                                                 Adjusted, with N02: 0.152
                                                                                                                 Adjusted, with S02: 0.158
                                                                                                                 3rd trimester
                                                                                                                 <90th percentile, N(%):
                                                                                                                 101 (56.4%): 3165 (49)
                                                                                                                 > 90th percentile, N(%): 11 (6.2%):
                                                                                                                 3087(147)
                 	P-Value for mean birth weight for
    December 2009                                                     E-472
    

    -------
                  Study                        Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                 > 90th percentile PM10 vs. for <90th
                                                                                                                 percentile PMi0
                                                                                                                 Adjusted: 0.626
                                                                                                                 Adjusted, with CO: 0.978
                                                                                                                 Adjusted, with N02: 0.551
                                                                                                                 Adjusted, with S02: 0.614
                                                                                                                 Genotype Ncol llelle
                                                                                                                 1st trimester
                                                                                                                 <90th percentile, N(%): 87 (49.7%):
                                                                                                                 3244 (52)
                                                                                                                 > 90th percentile, N(%): 7 (4.0%): 2983
                                                                                                                 (232)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM10 vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.289
                                                                                                                 Adjusted, with CO: 0.344
                                                                                                                 Adjusted, with N02: 0.641
                                                                                                                 Adjusted, with S02: 0.293
                                                                                                                 2nd trimester
                                                                                                                 <90th percentile, N(%): 82 (48.0%):
                                                                                                                 3243 (55)
                                                                                                                 > 90th percentile, N(%): 11 (6.4%):
                                                                                                                 3185(207)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM10 vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.790
                                                                                                                 Adjusted, with CO: 0.783
                                                                                                                 Adjusted, with N02: 0.707
                                                                                                                 Adjusted, with S02: 0.733
                                                                                                                 3rd trimester
                                                                                                                 <90th percentile, N(%): 90 (50.3%):
                                                                                                                 3239 (53)
                                                                                                                 > 90th percentile, N(%): 9 (5.0%): 2944
                                                                                                                 (198)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM10 vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.161
                                                                                                                 Adjusted, with CO: 0.279
                                                                                                                 Adjusted, with N02: 0.134
                                                                                                                 Adjusted, with S02: 0.150
                                                                                                                 Genotype Ncol HeVal/ValVal
                                                                                                                 1st trimester
                                                                                                                 <90th percentile, N(%): 71 (40.6%):
                                                                                                                 3262 (56)
                                                                                                                 > 90th percentile, N(%): 10(5.7%):
                                                                                                                 2773(171)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,o vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.009
                                                                                                                 Adjusted, with CO: 0.031
                                                                                                                 Adjusted, with N02: 0.058
                                                                                                                 Adjusted, with S02: 0.010
                                                                                                                 2nd trimester
                                                                                                                 <90th percentile, N(%): 71 (41.5%):
                                                                                                                 3264(61)
                                                                                                                 > 90th percentile, N(%): 7 (4.1%): 2862
                                                                                                                 (208)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,o vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.076
                                                                                                                 Adjusted, with CO: 0.093
                                                                                                                 Adjusted, with N02: 0.063
                                                                                                                 Adjusted, with S02: 0.061
                                                                                                                 3rd trimester
                                                                                                                 <90th percentile, N(%): 72 (40.2%):
                                                                                                                 3207 (58)
                                                                                                                 > 90th percentile, N(%): 8 (4.5%): 3262
                                                                                                                 (180)
                                                                                                                 P-Value for mean birth weight for
                                                                                                                 > 90th percentile PM,o vs. for <90th
                                                                                                                 percentile PM10
                                                                                                                 Adjusted: 0.777
                 	Adjusted, with CO: 0.607	
    December 2009                                                    E-473
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                 Adjusted, with N02: 0.843
                                                                                                                 Adjusted, with S02: 0.791
    Reference: Tsai et al. (2006, 0983121
    
    Period of Study: 1994-2000
    
    Location: Kaohsiung, Taiwan
    Outcome: Post neonatal mortality
    
    Age Groups: Infants more than 27
    days and less than 1 yr
    
    Study Design: Case-crossover study
    
    N: 207 deaths
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Temperature, humidity
    
    Dose-response Investigated? No
    
    Statistical Package: SAS, version 8.2
    Pollutant: PMi0
    
    Averaging Time: 24 h
    
    Mean(SD):81.45|jg/m3
    
    Percentiles: 26th: 44.50
    
    60th(Median): 79.20
    
    76th:111.50
    
    Range (Mm, Max): (20.50-232.00)
    
    Monitoring Stations: 6
    Copollutant:
    S02
    N02
    CO
    0,	
    PM Increment: 67.00 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    OR = 1.040 (0.340-3.177)
    
    Note: Air pollution levels at the dates of
    infant death were compared with air
    pollution levels 1 week before and  1
    week after death
    
    A cumulative lag up to 2 previous days
    was used to assign exposure.
    Reference: Wilhelm and Ritz  (2006,
    Period of Study: 1994-2000
    
    Location: Los Angeles County,
    California, U.S.
    Outcome: Term low birth weight (LBW)
    (<2500 g at > 37 completed wk
    gestation), Vaginal birth <37 completed
    wk gestation
    
    Age Groups: LBW: 2 37 completed wk
    
    Preterm births:  <37 completed wk
    
    Study Design: Cross-sectional
    
    N: For LBW: 136,134
    
    Forpreterm birth:
    
    106,483
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Maternal age, maternal
    race, maternal education, parity, interval
    since previous live birth, level of
    prenatal care, infant sex, previous LBW
    or preterm infant, birth season, other
    pollutants (CO,  N02, 03, PM10),
    gestational age (in birth weight analysis)
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    Pollutant: PM,0
    Averaging Time:
    24 h (every 6 days)
    Entire pregnancy
    Trimesters of pregnancy
    Months of pregnancy
    6 wk before birth
    
    Mean  (SD): First trimester: 42.2
    Third trimester: 41.5
    6 wk before birth: 39.1
    
    Range (Min, Max):
    First trimester: 26.3, 77.4
    Third trimester: 25.7, 74.6
    6 wk before birth: 13.0, 103.7
    
    Monitoring Stations:
    Zip-code-level analysis: 8
    Address-level analysis: 6
    
    Copollutant (correlation):
    First trimester: PMio-CO:r = 0.12
    PM,o-N02:r = 0.29
    PMio-03:r = -0.01
    PMio-PM25:r = 0.43
    Third trimester: PM10-CO: r = 0.32
    PMio-N02:r = 0.45
    PMio-03:r = -0.08
    PMio-PM25:r = 0.52
    6 wk before birth:
    PM10-CO:r = 0.36
    PM,o-N02:r = 0.49
    PMio-03:r = -0.16
    PM10-PM25:r = 0.60
    PM Increment:
    1)10|jg/m3
    2) 3 levels:
    a) <25 percentile (reference)
    b) 25%-75 percentile
    c) > 75 percentile
    Incidence of LBW (third trimester
    exposure)
    <32.8|jg/m3:2.0(1.8, 2.2)
    32.8to<43.4|jg/m3:2.0(1.9, 2.1)
    > 43.4 pg/m3: 2.2 (2.0, 2.4)
    Incidence of preterm birth (first
    trimester exposure)
    <32.9 pg/m3:8.7 (8.3, 9.2)
    32.9to<43.9|jg/m3:8.8(8.5, 9.1)
    > 43.9 pg/m3: 8.6 (8.1, 9.0)
    Incidence of preterm birth (6 wk
    before birth exposure)
    <31.8|jg/m3:8.8(8.4, 9.3)
    31.8to<44.1 pg/m3:8.6 (8.3, 8.9)
    a44.1 pg/m3: 8.8 (8.4, 9.2)
    Outcome: LBW
    Exposure Period: Third trimester
    Address-level analysis:
    Single-pollutant  model:
    Distance Ł 1 mile
    Per 10 pg/m3:1.22 (1.05,1.41)
    33.4 to <44.7|jg/m3:1.08 (0.76, 1.52)
    > 44.7 pg/m3:1.48 (1.00, 2.19)
    Multipollutant model:
    Distance < 1 mile
    Per 10 pg/m3:1.36 (1.12,1.65)
    33.4to<44.7|jg/m3:1.16 (0.77, 1.74)
    > 44.7 pg/m3:1.58 (0.95, 2.62)
    Single-pollutant  model:
    1  44.7 pg/m3: 0.96 (0.78, 1.18)
    Multipollutant model:
    1  44.7 pg/m3:1.02 (0.79, 1.32)
    Single-pollutant  model:
    2  45.0 pg/m3:1.08 (0.97, 1.20)
    Multipollutant model:
    2  45.0 pg/m3:1.06 (0.93,1.21)
    
    Zip-code-level analysis
    Single-pollutant  model:	
    December 2009
                                     E-474
    

    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
                                                                                                                  PeMOfjg/m°:1.03(0.97,1.09)
                                                                                                                  33.2 to <43.6|jg/m3:0.98 (0.86, 1.11)
                                                                                                                  > 43.6 pg/m3:1.03 (0.88, 1.21)
                                                                                                                  Multipollutant model:
                                                                                                                  Per 10 pg/m3:1.07 (0.99,1.15)
                                                                                                                  33.2 to <43.6|jg/m3: 0.97 (0.85, 1.12)
                                                                                                                  > 43.6 pg/m3:1.09 (0.90,1.31)
    
                                                                                                                  Outcome: LEW
                                                                                                                  Exposure Period: Entire pregnancy
                                                                                                                  period
                                                                                                                  Address-level analysis:
                                                                                                                  Multipollutant model:
                                                                                                                  Per 10 pg/m3:1.24 (0.91,1.70)
    
                                                                                                                  Outcome: Preterm Birth
                                                                                                                  Exposure Period: First trimester of
                                                                                                                  pregnancy
                                                                                                                  Address-level analysis:
                                                                                                                  Single-pollutant model:
                                                                                                                  Distance < 1 mile
                                                                                                                  Per 10 pg/m3:1.00 (0.93,1.09)
                                                                                                                  33.3to<45.1 pg/m3:1.07 (0.90, 1.26)
                                                                                                                  > 45.1 pg/m3:1.12 (0.91,1.38)
                                                                                                                  Multipollutant model:
                                                                                                                  Distance Ł 1 mile
                                                                                                                  Per 10 pg/m3:1.00 (0.90,1.12)
                                                                                                                  33.3to<45.1 |jg/m3:1.12(0.92, 1.36)
                                                                                                                  a45.1 pg/m3:1.17(0.90,1.50)
                                                                                                                  Single-pollutant model:
                                                                                                                  1  45.3 pg/m3:1.07 (0.97, 1.19)
                                                                                                                  Multipollutant model:
                                                                                                                  1  45.3 pg/m3:1.13 (1.00,1.27)
                                                                                                                  Single-pollutant model:
                                                                                                                  2  45.5 pg/m3:1.02 (0.96, 1.07)
                                                                                                                  Multipollutant model:
                                                                                                                  2  45.5 pg/m3: 0.94 (0.89, 1.01)
                                                                                                                  Zip-code-level analysis
                                                                                                                  Single-pollutant model:
                                                                                                                  Per 10 pg/m3: 0.99 (0.96,1.01)
                                                                                                                  33.3 to <44.2pg/m3:1.01 (0.95, 1.08)
                                                                                                                  > 44.2 pg/m3: 0.98 (0.90, 1.05)
                                                                                                                  Multipollutant model:
                                                                                                                  Per 10 pg/m3: 0.99 (0.96,1.03)
                                                                                                                  33.3 to <44.2pg/m3:1.03 (0.97, 1.11)
                                                                                                                  > 44.2 pg/m3:1.01 (0.92,1.11)
    
                                                                                                                  Outcome: Preterm birth
                                                                                                                  Exposure Period: 6 wk before birth
                                                                                                                  Address-level analysis:
                                                                                                                  Single-pollutant model:
                                                                                                                  Distance Ł 1 mile
                                                                                                                  Per 10 pg/m3:1.02 (0.95,1.10)
                                                                                                                  32.5to<44.8|jg/m3:1.09 (0.92, 1.29)
                                                                                                                  > 44.8 pg/m3:1.12 (0.92, 1.37)
                                                                                                                  Multipollutant model:
                                                                                                                  Distance Ł 1 mile
                                                                                                                  Per 10 pg/m3:1.06 (0.97,1.16)
                                                                                                                  32.5 to <44.8|jg/m3:1.09 (0.90, 1.31)
                                                                                                                  > 44.8 pg/m3:1.17 (0.91,1.49)
                                                                                                                  Single-pollutant model:
                                                                                                                  1  45.3 pg/m3: 0.99 (0.89, 1.10)
                                                                                                                  Multipollutant model:	
    December 2009                                                     E-475
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                 1  45.3 pg/m3:1.02 (0.91,1.16)
                                                                                                                 Single-pollutant model:
                                                                                                                 2  45.3 pg/m3: 0.98 (0.93, 1.03)
                                                                                                                 Multipollutant model:
                                                                                                                 2  45.3 pg/m3: 0.98 (0.92, 1.04)
    
                                                                                                                 Zip-code-level analysis
                                                                                                                 Single-pollutant model:
                                                                                                                 Per 10 pg/m3:1.02 (0.99,1.04)
                                                                                                                 32.1 to <44.3|jg/m3:1.01 (0.95, 1.07)
                                                                                                                 > 44.3 pg/m3:1.04 (0.96, 1.12)
                                                                                                                 Multipollutant model:
                                                                                                                 Per 10 pg/m3:1.02 (0.99,1.06)
                                                                                                                 32.1 to <44.3|jg/m3:1.02 (0.95, 1.09)
                                                                                                                 > 44.3 pg/m3:1.04 (0.95, 1.14)
                                                                                                                 Notes: multipollutant model adds
                                                                                                                 CO,N02, and 03 in addition to the main
                                                                                                                 pollutant of interest, PM10.
    Reference: Woodruff etal. (1997,
    0842711
    
    Period of Study: 1989-1991
    
    Location: 86 Metropolitan Statistical
    Areas in the U.S. (counties with
    populations less than 100,000 were
    excluded)
    Outcome: Postneonatal mortality
    (death of an infant between 1 month
    and 1 yr of age
    1)AII post neonatal deaths
    2) Normal birth weight (NBW, > 2500 g)
    SIDS deaths
    3) NBW respiratory deaths
    4) Low birth weight (LBW) respiratory
    death
    Respiratory deaths: ICD9 codes
    460-519
    
    SIDS: ICD9 code 798.0
    
    Age Groups: Infants (1 month-1yrof
    age)
    
    Study Design: Cross-sectional
    
    N: 3,788,079 infants
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Maternal education,
    maternal race, parental marital status,
    maternal smoking during pregnancy
    
    Avg temperature during the first 2 mo of
    life
    
    Infant's month and yr of birth
    
    Assessed race as an effect modifier
    (p-val for interaction terms >0.2)
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    Pollutant: PM,0
    
    Averaging Time: Mean of 1st 2 mo of
    life
    
    analyzed as tertiles of exposure and as
    continuous exposure
    
    Mean (SD): 31.4 (7.8)
    
    Range (Min, Max):
    
    Overall: 11.9-68.8
    
    Low category: <28.0
    
    Medium category: 28.1-40.0
    
    High category: >40.0
    
    Monitoring Stations: NR
    PM Increment: 10 pg/m  (for
    continuous exposure analysis)
    
    Adjusted ORs for cause-specific
    post neonatal mortality by pollution
    category (tertiles)
    All causes
    Low: Ref
    Medium: 1.05 (1.01,1.09)
    High: 1.10 (1.04,1.16)
    SIDS, NBW:
    Low: Ref
    Medium: 1.09 (1.01,1.17)
    High: 1.26 (1.14,1.39)
    Respiratory death, NBW:
    Low: Ref
    Medium: 1.08 (0.87,1.33)
    High: 1.40 (1.05,1.85)
    Respiratory death, LBW:
    Low: Ref
    Medium: 0.93 (0.73,1.18)
    High: 1.18 (0.86,1.61)
    All other causes:
    Low: Ref
    Medium: 1.03 (0.97,1.08)
    High: 0.97 (0.90, 1.04)
    
    Adjusted ORs for a continuous
    10 ug/m3 change in exposure
    All causes: 1.04 (1.02,1.07)
    SIDS, NBW: 1.12 (1.07,  1.17)
    Respiratory death, NBW: 1.20 (1.06,
    1.36)
    Respiratory death, LBW: 1.05(0.91,
    1.22)
    All other causes: 1.00 (0.99,1.00)
    December 2009
                                     E-476
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Woodruff etal. (2008,
    0983861
    Period of Study: 1999-2002
    Location: U.S. counties with >250,000
    residents (96 counties)
    Outcome: Postneonatal deaths
    Respiratory mortality (ICD10: JOOO-99,
    plus bronchopulmonary dysplasia [BPD]
    P27.1)
    SIDS(ICD10:R95)
    Ill-defined causes (R99);
    All other deaths evaluated as a control
    category
    Age Groups: Infants aged >28 days
    and <1 yr
    Study Design: Cross-sectional
    N: 3,583,495 births (6,639 post
    neonatal deaths)
    Statistical Analyses: Logistic GEE
    (exchangeable correlation structure)
    Covariates: Maternal race/ethnicity,
    marital status, age,  education,
    primiparity, county-level poverty and per
    capita income levels, yr and month of
    birth dummy variables to account for
    time trend and seasonal effects, and
    region of the country
    Sensitivity analyses performed among
    only those mothers with smoking
    information  (adjustment for smoking
    had no effect on the estimates)
    Season: Adjusted for yr and month of
    birth dummy variables to account for
    time trend and seasonal effects
    Dose-response Investigated?
    Evaluated the appropriateness of a
    linear form from analysis based on
    quartiles of exposure and concluded
    that linear form was appropriate (data
    not shown)
    Statistical Package: SAS
    Pollutant: PM,0
    Averaging Time: Measured
    continuously for 24 h once every 6 days
    exposure assigned by calculating avg
    concentration of pollutant during first 2
    mo of life
    Median and IQR (25th-75th
    percentile):
    Survivors: 28.9 (23.3-34.4)
    All causes of death: 29.1 (23.9-34.5)
    Respiratory: 29.8 (24.3-36.5)
    SIDS: 28.6 (23.5-33.8)
    SIDS+ill-defined: 28.8 (23.9-33.9)
    Other causes: 29.2 (23.9-34.5)
    Percent! les: see above
    PM Component: Not assessed, but
    controlled for region of the country to
    account for PM composition variation
    Monitoring Stations: NR
    Copollutant (correlation):
    PM10
    PM25(r = 0.34)
    CO (r = 0.18)
    S02(r = 0.00)
    03(r = 0.20)
    Notes: Monthly avg calculated if there
    were at least 3 available measures for
    PM
    Assigned exposures using the avg
    concentration of the county of residence
    PM Increment: IQR (11 pg/rri)
    Effect Estimate [Lower Cl, Upper Cl]:
    Adjusted ORs for single pollutant
    models
    All causes: 1.04 (0.99,1.10)
    Respiratory: 1.18 (1.06,1.31)
    SIDS: 1.02 (0.89, 1.16)
    Ill-defined + SIDS: 1.06 (0.97,1.16)
    Other causes: 1.02 (0.96,1.07)
    Adjusted ORs for multipollutant models
    (including CO, 03, S02)
    Respiratory: 1.16 (1.04,1.30)
    SIDS: 1.02 (0.90, 1.16)
    OR for deaths coded as BPD per
    increase in IQR: 1.19 (0.85,1.65)
    OR for respiratory post neonatal death
    stratified by birth weight
    NBW only: 1.19 (1.05,1.36)
    LBWonly: 1.12 (0.95,1.31)
    OR for respiratory deaths removing
    region of U.S. as  a confounding
    variable: 1.30 (1.04,1.61)
    OR for respiratory deaths assessing
    exposure as quartiles
    Highest  vs. Lowest quartile: 1.31 (1.00,
    1.71)
    OR for respiratory deaths among only
    those deaths that occurred during the
    first 90 days (most closely matched
    exposure metric of the avg over the first
    2 mo of  life): 1.25 (1.06,1.47)
    December 2009
                                     E-477
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Jedrychowski, et al., (2007,
    1566071
    
    Period of Study: Jan 2001-Feb 2004
    
    Location: Krakow, Poland
    Outcome: Birth weight (grams), birth
    length (cm)
    
    Age Groups: Pregnant women 18-35
    yr
    
    Study Design: Prospective cohort
    
    N: 493 women
    
    Statistical Analyses: Linear regression
    
    Covariates:  Environmental tobacco
    smoke (# cigarettes smoked daily in
    presence of pregnant woman), season
    of birth, size of mother, parity,
    gestational age, gender of child, vitamin
    A intake
    
    Season: All
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    
    Lags Considered: Two consecutive
    days in the second trimester
    Pollutant: PM25
    
    Averaging Time: 48 h period
    
    Percentiles: 60th(Median): 35.3
    
    Range (Mm, Max): 10.3, 294.9
    
    Monitoring Stations: No stations,
    personal monitoring
    
    Notes: PM measured during a 2 day
    period in the second trimester by
    Personal Environmental Monitoring
    Sampler (PEMS)
    PM Increment: in 1 pg/rrf and tertiles
    T1:<27.0|jg/m3
    T2: 27.0-46.2 pg/m3
    T3:a46.2fjg/nr
    Mean [Lower Cl, Upper Cl]:
    Birth weight (g)
    For In unit PM:|3 = -172.39 (p = 0.02)
    Tertiles:
    T1:ref
    T2:|3 =-16.510 [-94.630, 61.610]
    T3:|3 =-109.956 [-196.649 to-23.263]
    In low Vitamin A group (<1,378 pg)
    T1:ref
    T2:|3 =-68.354 [-165.643, 28.935]
    T3: (3 = -185.070 [-293.393 to -76.747]
    In high Vitamin A group (>1,378 pg)
    T1: ref
    T2: (3 = 64.262 [-70.464, 198.988]
    T3: (3 = 38.593 [-109.853, 187.039]
    Birth length (cm)
    For In unit PM: (3 = -1.39 (p = 0.00)
    Tertiles:
    T1:ref
    T2: (3 = -0.288 [-0.790, 0.214]
    T3: (3 = -0.810 [-1.367 to-0.253]
    In low Vitamin A group (<1,378 |jg)
    T1:ref
                                                                            T2: (3 = -0.514
                                                                            T3: (3 = -1.100
                                                                                                                              -1.114,0.086]
                                                                                                                              -1.768 to-0.432]
                                                                                                                 In high Vitamin A group (>1,378 |jg)
                                                                                                                 T1:ref
                                                                                                                 T2: (3 = 0.039 [-0.896, 0.974]
                                                                                                                 T3: (3 = -0.301 [-1.326,0.724]
    Reference: (Lipfert et al., 2000,
    0041031
    
    Period of Study: 1990
    
    Location: U.S.
    Outcome (ICD9 and ICD10): Infant
    mortality
    
    Including respiratory mortality
    (traditional definition, ICD9 460-519),
    expanded definition (adds ICD9 769
    and 770)
    
    Age Groups: Infants
    
    Study Design: Cross-sectional
    
    N: 2,413,762 infants in 180 counties
    (Ns differ for various models)
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Mother's smoking,
    education,  marital status, and race
    
    Month of birth
    
    And county avg heating degree days
    
    Dose-response Investigated? NR
    
    Statistical Package: NR
    Pollutant: S04 7NSPM,0 (regressed
    jointly)
    
    Averaging Time: Yearly avg used
    
    Mean (SD): 33.1 (9.17) (based on 180
    counties)
    
    Range (Min, Max): (16.9, 59)
    
    Monitoring Stations: NR
    
    Copollutant:
    
    PM10
    
    NSPM,o
    
    CO
    
    S02
    
    Notes: TSP-based sulfate was adjusted
    for compatibility with the PM10-based
    data
    PM Increment: NR (present regression
    coefficients)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Presented regression coefficients
    (standard errors)
    (3 PM exposures regressed jointly)
    bold = p O.05
    Cause of death: All
    Birth weight: All
    S042":-0.0002 (0.0061)
    NSPM10: 0.0115 (0.0014)
    Cause of death: All
    Birth weight: LBW
    S042": 0.0265 (0.0080)
    NSPM,0: 0.0086 (0.0020)
    Cause of death: All
    Birth weight: normal
    S042": -0.0488 (0.0098)
    NSPM10: 0.0096 (0.0024)
    Cause of death: All neonatal
    Birth weight: All
    S042": 0.0267 (0.0076)
    NSPM10: 0.0126 (0.0018)
    Cause of death: All neonatal
    Birth weight: LBW
    S042": 0.0388 (0.0088)
    NSPM,0: 0.0093 (0.0022)
    Cause of death: All neonatal
    Birth wt: normal
    S042":-0.0334 (0.0169)
    NSPM10: 0.0125 (0.0040)
    Cause of death: All post neonatal
    Birth wt: All
    PM,,: 0.0091 (0.0024)
    S04 : -0.0474 (0.0100)
    NSPM,0: 0.0096 (0.0024)
    Cause of death: All post neonatal
    Birth wt: LBW
    S042":-0.0247 (0.0173)
    NSPM10: 0.0101  (0.0042)
    Cause of death: All post neonatal
    Birth wt: normal
    S042":-0.0569 (0.0121)	
    December 2009
                                     E-478
    

    -------
                  Study                       Design & Methods                 Concentrations1             Effect Estimates (95% Cl)
    
                                                                                                               NSPM10: 0.0080 (0.0029)
                                                                                                               Cause of death: SIDS
                                                                                                               Birth weight: All
                                                                                                               S042":-0.1078 (0.0151)
                                                                                                               NSPM,0: 0.0149 (0.0037)
                                                                                                               Cause of death: SIDS
                                                                                                               Birth weight: LBW
                                                                                                               S042":-0.1378 (0.0337)
                                                                                                               NSPM10: 0.0146 (0.0085)
                                                                                                               Cause of death: SIDS
                                                                                                               Birth weight: normal
                                                                                                               PIVU 0.0137 (0.0042)
                                                                                                               S04:-0.0995 (0.0168)
                                                                                                               NSPM,0: 0.0147 (0.0041)
                                                                                                               Cause of death: All respiratory (ICD9:
                                                                                                               460-519, 769, 770)
                                                                                                               Birth weight: All
                                                                                                               S042": 0.0706 (0.0146)
                                                                                                               NSPM10: 0.0166 (0.0034)
                                                                                                               Cause of death: All respiratory (ICD9:
                                                                                                               460-519, 769, 770)
                                                                                                               Birth weight: LBW
                                                                                                               S042": 0.0821  (0.0158)
                                                                                                               NSPM10: 0.0139 (0.0038)
                                                                                                               Cause of death: All respiratory (ICD9:
                                                                                                               460-519, 769, 770)
                                                                                                               Birth weight: normal
                                                                                                               PM,n: 0.0177 (0.0091)
                                                                                                               S04  :0.0001  (0.0392)
                                                                                                               NSPM10: 0.0118 (0.0090)
                                                                                                               Cause of death: Respiratory disease
                                                                                                               (ICD9: 460-519)
                                                                                                               Birth weight: All
                                                                                                               PM,,: 0.0133 (0.0089)
                                                                                                               S04  :0.0093 (0.0384)
                                                                                                               NSPM10: 0.0134 (0.0089)
                                                                                                               Cause of death: Respiratory disease
                                                                                                               (ICD9: 460-519)
                                                                                                               Birth weight: LBW
                                                                                                               PM,n: 0.0092 (0.0137)
                                                                                                               S04  :0.0434 (0.0580)
                                                                                                               NSPM10: 0.0089 (0.0138)
                                                                                                               Cause of death: Respiratory disease
                                                                                                               (ICD9: 460-519)
                                                                                                               Birth weight: normal
                                                                                                               S042":-0.0177 (0.0509)
                                                                                                               NSPMy 0.0128 (0.0119)
                                                                                                               Associations with SIDS by smoking
                                                                                                               status
                                                                                                               Smoking status: Yes
                                                                                                               Birth weight: Normal
                                                                                                               S042": -0.0722 (0.0284)
                                                                                                               NSPM,0: 0.0206 (0.0071)
                                                                                                               Smoking status: No
                                                                                                               Birth weight: Normal
                                                                                                               S042":-0.114 (0.021)
                                                                                                               NSPM10: 0.0117 (0.005)
                                                                                                               Smoking status: Yes
                                                                                                               Birth weight: LBW
                                                                                                               S042": -0.0958 (0.0483)
                                                                                                               NSPM10: 0.0345 (0.0125)
                                                                                                               Smoking status: No
                                                                                                               Birth weight: LBW
                                                                                                               S042": -0.0172 (0.047)
                                                                                                               NSPM,0: -0.0007  (0.012)
                                                                                                               Mean risks (95%CI) between post
                                                                                                               neonatal SIDS among normal birth
                                                                                                               weight babies
                                                                                                               pollutants regressed one at a time
                                                                                                               S042": 0.43 (0.37, 0.51)
                 	NSPM10:1.33 (1.18, 1.50)	
    December 2009                                                   E-479
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: (Liu et al, 2007, 0904291
    
    Period of Study: 1985-2000
    
    Location: 3 Canadian cities: Calgary,
    Edmonton, and Montreal
    Outcome: Intrauterine growth
    restriction (IUGR)
    
    Age Groups: Singleton term live births
    (37-42 wks gestation)
    
    Study Design: Retrospective cohort
    
    N: 386,202 singleton live births
    
    Statistical Analyses: Multiple logistic
    regression
    
    Covariates:  Maternal age, parity, infant
    gender, season, and city of residence at
    time period of birth
    
    Season: All seasons
    
    Dose-response Investigated? No
    
    Statistical Package: NR
    Pollutant: PM,
    PM Increment: 10 pg/m
    Averaging Time: 24 h (6-day schedule)  Effect Estimate
    Mean (SD): 12.2
    
    Percentiles: 26th: 6.3
    
    60th(Median): 9.7
    
    76th:15
    
    PM Component: metals and organic
    matter such as polycyclic aromatic
    hydrocarbons
    
    Monitoring Stations: Calgary (4),
    Edmonton (2), and Montreal (8)
    Copollutant (correlation):
    S02: r = 0.44, p< 0.0001
    N02: r = 0.41, p< 0.0001
    CO: r = 0.31, p< 0.0001
    03: r =-0.14, p< 0.0001
    Single-pollutant model [Lower Cl,
    Upper Cl]:
    1st trimester
    OR =  1.07 (1.03-1.10)
    2nd trimester
    OR =  1.06 (1.03-1.10)
    3rd trimester
    OR =  1.06 (1.03-1.10)
    
    Effect Estimate
    multi-pollutant model [Lower Cl,
    Upper Cl]:
    1st trimester
    OR= 1.03 (0.99-1.06)
    2nd trimester
    OR=1.01 (0.98-1.05)
    3rd trimester
    OR= 1.03 (0.99-1.06)
    Note: ORs and CIs estimated from Fig.
    6 and 7
    Reference: Loomisetal. (1999,
    0872881
    
    Period of Study: Jan 1993-Jul 1995
    
    Location: Mexico City (southwestern
    section)
    Outcome (ICD9 and ICD10): Infant
    mortality (daily counts of deaths)
    
    All ICD9 codes, excluding accidents,
    poisoning, and violence (ICD9 >800)
    
    Age Groups: Children <1 yrof age
    
    Study Design: Time-series
    
    N: 942 deaths (days were the unit of
    observation)
    
    Statistical Analyses: Poisson
    regression (generalized additive model)
    
    Covariates: Final models controlled for
    mean temp  of 3 days before death and
    nonparametrically smoothed periodic
    cycles
    
    Season: Yes (considered)
    
    Dose-response Investigated? Loess
    smoother
    
    Statistical Package: NR
    
    Lags Considered: 0-5 (also
    considered  lags with avg exposure
    levels during "windows" of 2 to 4 days)
    Pollutant: PM25
    
    Averaging Time: 24-h
    
    Mean (SD): 27.4 (10.5)
    
    Percentiles: Lower quartile: 20
    
    Median: 26
    
    Upper quartile: 34
    
    Range (Min, Max): 4, 85
    
    Monitoring Stations: 1
    
    Copollutant:
    03
    
    N02
    
    NO
    
    NOX
    
    S02
    
    Notes: Pearson correlation coefficients
    ranging from 0.52 to 0.71
    PM Increment: 10 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    %Change in infant mortality
    Lags 0-5 (single day) presented in Fig
    
    LagO,1,2: No association (results not
    presented)
    Lag3: 4.8 (0.97, 8.61)
    Lag4: 4.2 (0.37, 7.93)
    %Change in mortality when avg
    exposure levels during "windows" of 2
    to 4 days were considered
    2 Days:
    No lag:-1.36 (-5.51, 2.8)
    Lag 1:-0.95 (-5.10, 3.20)
    Lag2: 2.78 (-1.33, 6.89)
    Lag3: 4.93 (0.86, 9.01)
    3 Days:
    No lag: -0.81  (-5.29, 3.67)
    Lag 1:1.99 (-2.46, 6.45)
    Lag2: 4.54 (0.12, 8.96)
    Lag3: 6.87 (2.48, 11.26)
    4 Days:
    No lag: 1.95 (-2.76, 6.66)
    Lag 1:3.74 (-0.95, 8.42)
    Lag2: 5.87 (1.21, 10.53)
    Multipollutant models (3-day mean w/ 3-
    day lag)
    1 pollutant model:
    6.87(2.48,11.26)
    2 pollutant models:
    w/03: 6.24 (1.35, 11.14)
    w/N02:5.91  (-0.76, 12.59)
    3 Pollutant model (w/ 03 and N02):
    6.30 (-0.54, 13.15)  	
    December 2009
                                    E-480
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Mannes et al. (2005,
    0878951
    
    Period of Study: Jan 1998-Dec 2000
    
    Location: metropolitan Sydney,
    Australia
    Outcome: Risk of small for gestational
    age (SGA) and birth weight
    
    Age Groups: All singleton births >20
    wk and > 400 grams birth weight and
    maternal all ages
    
    Study Design: Cross-sectional
    
    N: 138,056 singleton births
    
    Statistical Analyses: Logistic and
    linear regression models
    
    Covariates:  Sex of child, maternal age,
    gestational age, maternal smoking,
    gestational age at first antenatal visit,
    maternal indigenous status, whether
    first pregnancy, season of birth, and
    socioeconomic status (SES)
    
    Season: All seasons
    
    included as covariate.
    
    Dose-response Investigated? No
    
    Statistical Package: SAS System for
    Windows v8.02
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD): 9.4 (5.1)
    
    Percentiles: 26th: 6.5
    
    60th(Median): 8.4
    
    76th: 11.2
    
    Range (Min, Max): (2.4-82.1)
    
    Monitoring Stations: up to 14
    
    Copollutant (correlation):
    
    CO: r = 0.53
    
    N02:r = 0.66
    
    03:r = 0.36
    
    PM,o:r = 0.81
    PM Increment: 1 pg/m
    Risk of SGA
    All births
    1 month before birth:
    OR = 1.01 (0.99-1.03)
    Third trimester: OR = 0.99 (0.97-1.02)
    Second trimester:
    OR = 1.03 (1.01-1.05)
    First trimester: OR = 0.99 (0.97-1.01)
    5 km births
    1 month before birth:
    OR = 1.01 (0.97-1.04)
    Third trimester: OR = 1.00 (0.95-1.05)
    Second trimester:
    OR = 1.00 (0.96-1.05)
    First trimester: OR = 0.99 (0.94-1.04)
    Change in birth weight
    All births
    1 month before birth:
     IS = -2.48 (-4.58--0.38)
    Third trimester: IS = -0.98 (-3.74-1.78)
    Second trimester:
    IS = -4.10 (-6.79--1.41)
    First trimesters = 0.36 (-2.29-3.01)
    5 km births
    1 month before birth:
    IS = -2.70 (-6.80-1.40)
    Third trimester: IS = -2.83 (-9.00-3.34)
    Second trimester: IS = 1.54 (-4.59-7.67)
    First trimester: IS =1.89 (-1.99-5.77)
    Reference: Parker et al. (2005,
    0874621
    
    Period of Study: 1999-2000
    
    Location: California
    Outcome: Small for gestational age
    (SGA) and birth weight
    
    Age Groups: Infants delivered at 40 wk
    gestation
    
    maternal all ages
    
    Study Design: Cross-sectional
    
    N: 18,247 singleton births
    
    Statistical Analyses: Linear and
    logistic regression models
    
    Covariates: Maternal race, maternal
    Hispanic origin, marital status, parity,
    maternal education, and maternal age
    
    Season: Season of delivery (covariate)
    
    Dose-response Investigated? Yes
    
    Statistical Package: STATA
    Pollutant: PM25
    
    Averaging Time: NR (measurement
    taken every 6 days)
    
    Mean (SD): 15.42 (5.08)
    
    PM Component: metals, polycyclic
    aromatic hydrocarbons
    
    Monitoring Stations: 40
    
    Copollutant (correlation):
    
    PM25-CO:r = 0.6
    
    Notes: Mean calculated for 9-month
    exposure. The following means (SDs)
    are calculated for trimester:
    
    First: 15.70 (6.26)
    
    Second: 15. 40 (6. 53)
    
    Third: 14.29 (6.35)
    
    PM categorized into quartiles:
                                                                             02:11.9-13.9
    
                                                                             03: 13.9-18.4
    
                                                                             04: >18.4
    PM Increment: <11.9 pg/m |
    
    Referent PM Increment: 11.9-
    13.9|jg/m3
    
    Effect Estimate [Lower Cl, Upper Cl]:
    First Trimester
    Birth weight: IS = -5.7 (-27.9-16.5)
    SGA: OR =1.02 (0.84-1.23)
    Second Trimester
    Birth weight: IS =11.3 (-12.2-34.9)
    SGA: OR = 0.89 (0.73-1.09)
    Third Trimester
    Birth weight: IS = 8.3 (-13.1-29.8)
    SGA: OR =1.00 (0.83-1.19)
    PM Increment: 13.9-18.4 pg/m
    Effect Estimate [Lower Cl, Upper Cl]:
    First Trimester
    Birth weight: IS = -2.5 (-24.5-19.5)
    SGA: OR =1.12 (0.93-1.34)
    Second Trimester
    Birth weight: IS = -17.2 (-39.4-4.9)
    SGA: OR =1.05 (0.88-1.26)
    Third Trimester
    Birth weight: IS = -8.1 (-30.2-13.9)
    SGA: OR = 0.98 (0.82-1.181
    PM Increment: >18.4 pg/m
    Effect Estimate [Lower Cl, Upper Cl]:
    First Trimester
    Birth weight: IS = -35.8 (-58.4--13.3)
    SGA: OR =1.26 (1.04-1.51)
    Second Trimester
    Birth weight: IS = -46.6 (-68.6- -24.6)
    SGA: OR =1.24 (1.04-1.49)
    Third Trimester
    Birth weight: IS = -31.6 (-52.0- -11.1)
    SGA: OR =1.21 (1.02-1.43)	
    December 2009
                                     E-481
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Parker and Woodruff
    (2008,156846)
    
    Period of Study: 2001-2003
    
    Location: U.S.
    Outcome: Low birth weight
    
    Study Design: Cohort
    Pollutant: PM25
    
    Averaging Time: 9 mo
    N: 785,965 Singleton births delivered at  Mean (SD): 14.5
    40 wk gestation
         a                             25th: 12.1
    Statistical Analyses: GEE regression
                                       models
    
                                       linear and logistic regression
    
                                       Covariates: Race/ethnicity, parity,
                                       maternal age
    
                                       Season: Season of delivery
    
                                       Statistical Package: SUDAAN
                                       75th: 17.6
    
                                       Copollutant (correlation):
                                       S02, N02 CO 03
    PM Increment: 10 pg/m
    
    Change in Birth weight (9 month
    exposure):
    Unadjusted: 19.4 (9.8, 29.0)
    Adjusted for maternal factors:
    18.4(9.2,27.7)
    Stratified by region:
    Industrial Midwest: -15.3 (-43.4,12.9)
    Northeast:-9.8 (-11.9, 26.6)
    Northwest: 27.5 (5.5, 49.4)
    Southern CA: 5.5 (-9.6, 20.5)
    Southeast: 7.3 (-11.9, 26.6)
    Southwest: 72.3 (34.0,110.5)
    Upper Midwest: -0.7  (-62.0, 60.6)
    Multipollutant models:
    PM25+PMio.25:14.2 (4.3, 24.1)
    PM25+PM10.25+S02+CO+N02+03: 28.6
    (14.2, 43.0)
    December 2009
                                   E-482
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Rich et al. (2009,1801221
    
    Period of Study: 1999-2003
    
    Location: New Jersey, United States
    Outcome: Small for gestational age
    
    Study Design: Retrospective Cohort
    
    Covariates: Month and calendar yr of
    birth, apparent temperature, pregnancy
    complications
    
    Statistical Analysis: Polytomous
    logistic regression
    
    Statistical Package: SAS
    
    Age Groups: Gestational age 37-42
    wks
    Pollutant: PM25
    
    Averaging Time: 24 h
    
    Mean (SD) Unit:
    
    *AII values are for first trimester, other
    trimesters are available in paper
    
    Reference Births: 13.8(2.5)
    
    SGA Births: 13.9 (2.5)
    
    VSGA Births:  13.9 (2.4)
    
    Range (Min, Max): 2.0, 29.0
    
    Copollutant (correlation):
    
    *AII values are for first trimester, other
    trimesters are available in paper
    
    N02: 0.01
    
    S02:0.17
    
    CO: 0.25
    *AII values are for first trimester, other
    trimesters are available in paper
    
    Increment: 4 pg/m3
    
    Percent Change in Risk (96% Cl)
    SGA: 4.5 (0.5-8.7)
    VSGA: 2.6 (-4.4-10.0)
    Percent Change in Risk (96% Cl) for
    single and two-pollutant models
    Single, SGA: 4.6 (-0.3-9.8)
    Single, VSGA: 4.5 (-4.0-13.4)
    Two  (PM25 SN02), SGA: 4.5 (-0.4-9.7)
    Two  (PM25 & N02), VSGA: 3.2 (-5.2-
    12.4)
    Percent Change in Risk (96% Cl) by
    pregnancy complication in third
    trimester
    SGA
    Any Complication
    No: 4.7 (0.6-9.0)
    Yes:  2.2 (-6.1-11.3)
    Placental Abruption
    No: 4.0 (0.3-7.9)
    Yes:  11.7 (-21.7-59.5)
    Placental Praevia
    No: 3.9 (0.2-7.8)
    Yes:  23.2 (-20.9-91.9)
    Pre-eclampsia
    No: 4.2 (0.4-8.2)
    Yes:  2.7 (-13.8-22.3)
    Gestational Hypertension
    No: 4.3 (0.4-8.4)
    Yes:  3.9 (-7.8-17.1)
    Premature Rupture of the Membrane
    No: 3.7 (-0.1-7.7)
    Yes:  14.6 (-3.3-35.9)
    Gestational Diabetes
    No: 4.6 (0.8-8.6)
    Yes:  -9.3 (-24.7-9.3)
    VSGA
    Any Complication
    No: 1.5 (-6.1-9.7)
    Yes:  12.6 (0.1-26.7)
    Placental Abruption
    No: 4.1 (-2.6-11.2)
    Yes:  7.6 (-29.8-64.9)
    Placental Praevia
    No: 4.1 (-2.5-11.2)
    Yes:  3.2 (-43.0-86.9)
    Pre-eclampsia
    No: 4.4 (-2.6-11.9)
    Yes:  3.9 (-15.7-28.1)
    Gestational Hypertension
    No: 3.2 (-4.0-10.9)
    Yes:  12.9 (-3.3-31.9)
    Premature Rupture of the Membrane
    No: 3.3 (-3.5-10.5)
    Yes:  21.9 (-3.6-54.2)
    Gestational Diabetes
    No: 4.3 (-2.5-11.5)
    Yes:  1.4 (-27.0-40.9)	
    December 2009
                                     E-483
    

    -------
                  Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Ritz et al. (2007, 0961461
    
    Period of Study: Jan 2003-Dec 2003
    
    Location: Los Angeles, California
    Outcome: Preterm births (infants
    delivered before 37 wk)
    
    Age Groups: Births
    
    Study Design: Case-control nested
    within a birth cohort (cases and controls
    matched on zip code and birth month)
    
    Phase 1: cross-sectional including all
    birth cohort
    
    Phase 2: nested case-control of survey
    respondents
    
    N: Phase 1: Birth cohort consisted of
    58,316 eligible births.  Phase II: 2,543
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Birth certificate
    information: maternal  age,
    race/ethnicity, parity, education, season
    of birth
    
    survey information: maternal smoking,
    alcohol consumption,  living with a
    smoker, and marital status during
    pregnancy
    
    income (imputed)
    
    occupation and pregnancy weight gain
    considered but not included in final
    models
    
    Season: Yes
    
    Dose-response Investigated? Yes,
    examined categories of exposure
    
    Statistical Package:  NR
    Pollutant: PM25
    
    Averaging Time: daily or every 3rd day
    used to calculate the entire pregnancy,
    the first trimester, and the last 6 wk
    before delivery
    
    Only reported first trimester exposures
    forPM
    
    Range (Min, Max): NR
    
    Ranges for 3 categories reported:
    
    Low (ref):< 18.63
    
    Mid: 18.64-21.36
    
    High:  >21.36
    
    Monitoring Stations: Each zip code
    was linked to the nearest monitoring
    station (number not reported)
    
    Copollutant (correlation):
    CO
    
    N02
    
    03
    
    Notes: Daily or every 3rd day
    measurements used for mean
    calculations
    PM Increment: Reported analyses
    using exposure categories
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Birth cohort (phase I)
    Crude:  Low: 1.0
    Mid: 0.96 (0.90, 1.03)
    High: 1.05 (0.99,1.12)
    
    Adj for birth cert Covariates: Low: 1.0
    Mid: 1.01 (0.93, 1.09)
    High: 1.10 (1.01,1.20)
    
    Survey respondents (phase II)
    Crude:  Low: 1.0'Mid:  1.11  (0.90,1.36)
    High: 1.27 (1.06, 1.53)
    
    Adj for birth cert Covariates: Low: 1.0
    Mid: 1.14 (0.90, 1.46)
    High: 1.27 (0.99, 1.64)
    
    Adj for all Covariates: Low: 1.0
    Mid: 1.15 (0.90, 1.47)
    High: 1.29 (1.00,1.67)
    
    Two-phase model: * Low: 1.0
    Mid: 0.98 (0.84, 1.15)
    High: 1.07 (0.85, 1.35)
    
    'Method to reduce potential selection
    bias and increase statistical efficiency
    Reference: Slama et al. (2007, 0932161
    
    Period of Study: Jan 1998-Jan 1999
    
    Location: Munich, Germany
     Outcome: Birth weight offspring at term
    
     Study Design: Cohort study
    
     N: 1016 births
    
     Statistical Analyses: Poisson model
    
     Covariates: Maternal passive smoking,
     maternal age, gestational duration, sex
     of child, parity, maternal education,
     maternal size,  prepregnancy weight,
     other pollutants (PM25, PM25
     absorbance, N02), season of conception
    
     Dose-response  Investigated? Yes
    
     Statistical Package: STATA
     Pollutant: PM25 (estimated based on
     larger PM size fractions)
    
     Averaging Time: Entire pregnancy
     period and trimesters
    
      Mean (SD): 14.4
    
     Percentiles: 26th:  13.5
    
     60th(Median): 14.4
    
     76th: 15.4
    
     Monitoring Stations: Spatial
     component: 40
    
     Temporal component: 1
     Copollutant (correlation):
     p.a. = pregnancy avg
     trim. = trimester
     PM25(p.a.)-PM25 (1sttrim.): 0.85
     PM25(p.a.)-PM25 (2nd trim.): 0.77
                                                                               PM25  p.a.
                                                                               PM25  p.a.
                                                                               PM25  p.a.)-NQ, (1sttrim.): 0.18
                                                    -PM25 (3rd trim.): 0.87
                                                    -N02 (p.a.): 0.45
                                                                               PM25  p.a.
                                                                               PM25  p.a.
                                                                               PM25  1sttrim.)-PM25 (2nd trim.): 0.40
                                                    -N02 (2nd trim.): 0.32
                                                    -N02 (3rd trim.): 0.37
                                                                                     1st trim.
                                                                               PM25
                                                                               PM25
                                                                               PM25 (1sttrim.)-N02 (1sttrim.): 0.15
                                                1st trim.
                   -PM25 (3rd trim.): 0.68
                   -N02 (p.a.): 0.48
                                                                                     1st trim.
                                                                                     1st trim.
                                                                                            -N02
                                                             2nd trim.): 0.41
     PM25
     PM25
     PM25 (2ndtrim.)-PM25 (3rd trim.): 0.51
                                                                                            -N02
                                                             3rd trim.): 0.39
                                                                               PM25 2nd trim.)-N02 (p.a.): 0.23
                                                                               PM25 2nd trim.)-N02 (1sttrim.):-0.03
                                                                               PM25 (2nd trim.)-N02 (2nd trim.): 0.17
                                                                               PM25 (2ndtrim.)-N02 (3rd trim.): 0.30
      PM Increment:
      1  1  pg/m3
      2  Quartiles:
      a) 1st (reference) (7.2-13.5 pg/m3)
      b) 2nd (13.5-14.4 pg/m3)
      c) 3rd (14.4-15.4 pg/m3)
      day) 4th (15.41-17.5 pg/m3)
      Prevalence ratios (PRs) of birth
      weight <3000 g during exposure over
      the whole pregnancy
      Single-pollutant models
      Unadjusted models
      2nd quartile: 1.07 (0.65,1.73); 3rd
      quartile: 1.38 (0.91, 2.09)
      4th quartile: 1.45 (0.92, 2.25)
      Perl pg/m3:1.06 (0.95,1.19)
      Adjusted models
      2nd quartile: 1.08 (0.63,1.82); 3rd
      quartile: 1.34 (0.86, 2.13)
      4th quartile: 1.73 (1.15, 2.69); Per
      1 pg/m3:1.13 (1.00,1.29)
    
      Multipollutant models
      Adjusted models
      2nd quartile: 1.01  (0.57,1.85)
      3rd quartile: 1.12 (0.64,1.87)
      4th quartile: 1.36 (0.72, 2.45); Per
      1 pg/m3:1.07 (0.91,1.26)
    
      Single-pollutant models (restricted
      analysis to PM25 absorbance below the
      median)
      Perl pg/m3:1.15 (0.89,1.52)
    
      Prevalence ratios (PRs) of birth
      weight <3000 g
      Multipollutant models (simultaneous
    December 2009
                                     E-484
    

    -------
                  Study
           Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                              PM25
                                                                              PM25
                                                                              PM25
                                                                              PM25
                                                                              PM25
                                                                              0.69
                                                                              PM25
                                                                              PM25
                                                                              PM25
                                                                              PM25
                                                                              PM25
                                                                              0.27
                                                                              PM25
                                                                              0.53
                                                                              PM25
                                                                              0.51
                                                                              PM25
                                                                              PM25
                                                                              0.08
                                                                              PM25
                                                                              0.29
                                                                              PM25
                                                                              0.41
                                                                              PM25
                                                                              PM25
                                                                              0.48
                                                                              PM25
                                                                              0.36
                                                                              PM25
                                                                              0.37
                                              (3rd trim.)-N02 (p.a): 0.39
                                               3rd trim.)-N02 (1st trim.): 0.33
                                               3rd trim.)-N02 (2nd trim.): 0.21
                                              (3rd trim.)-N02 (3rd trim.): 0.23
                                              (p.a.)- PM25 absorbance (p.a.):
    
                                              (p.a.)-PM2.5abs (1st trim.): 0.33
                                                   -PM25abs(2ndtrim.):0.48
                                                   - PM25 abs (3rd trim.): 0.52
                                              (1sttrim.)-PM25abs(p.a.j: 0.68
                                              (1sttrim.)-PM25 abs (1sttrim.):
    
                                              (1st trim.)-PM25 abs (2nd trim.):
    
                                              (1sttrim.)-PM25 abs (3rd trim.):
    
                                               2ndtrim.)-PM25abs(p.a.):0.41
                                               2nd trim.)-PM25 abs (1st trim.):
    
                                              (2nd trim.)- PM25 abs (2nd trim.):
    
                                              (2nd trim.)- PM25 abs (3rd trim.):
    
                                              (3rd trim.)-PM25 abs (p.a.): 0.62
                                              (3rd trim.)-PM25 abs (1sttrim.):
    
                                              (3rd trim.)-PM25 abs (2nd trim.):
    
                                              (3rd trim.)- PM25 abs (3rd trim.):
                                 Adjustment of 3rd trimester Plfeand
                                 whole pregnancy PMu)
    
                                 PM25 (whole pregnancy)
                                 Perl pg/m3: 0.96 (0.75,1.19)
                                 PM25 (3rd trimester)
                                 Perl pg/m3:1.17 (0.98,1.40)
    
                                 Prevalence ratios (PRs) of birth
                                 weight <3000 g during exposure over
                                 the whole pregnancy (adjustment for
                                 season of conception)
                                 4th quartile: 1.68 (1.05, 2.75); Per
                                 1 |jg/m3:1.12(0.97,1.28)
                                 Prevalence ratios (PRs) of birth
                                 weight <3000 g during exposure over
                                 first trimester of pregnancy
                                 Each trimester separately
                                 2nd quartile: 1.14 (0.74,1.96); 3rd
                                 quartile: 1.28 (0.84, 2.10)
                                 4th quartile: 1.65 (1.02, 2.60)
                                 Perl pg/m3:1.10 (0.99,1.20)
                                 All trimesters adjusted simultaneously
                                 2nd quartile: 0.97 (0.60,1.73); 3rd
                                 quartile: 0.98 (0.57,1.75)
                                 4th quartile: 1.22 (0.71, 2.18)
                                 Perl pg/m3:1.03 (0.90,1.17)
    
                                 Prevalence ratios (PRs) of birth
                                 weight <3000 g during exposure over
                                 second trimester of pregnancy
                                 Each trimester separately
                                 2nd quartile: 0.83 (0.52,1.32); 3rd
                                 quartile: 1.08 (0.71,1.60)
                                 4th quartile: 0.94 (0.61,1.47)
                                 Perl pg/m3:1.01 (0.92,1.12)
                                 All trimesters adjusted simultaneously
                                 2nd quartile: 0.75 (0.46,1.24)
                                 3rd quartile: 0.86 (0.56,1.30);
                                 4th quartile: 0.75 (0.48,1.23)
                                 Perl pg/m3: 0.94 (0.84,1.06)
    
                                 Prevalence ratios (PRs) of birth
                                 weight <3000 g during exposure over
                                 third trimester of pregnancy
                                 Each trimester separately
                                 2nd quartile: 1.30 (0.80, 2.17)
                                 3rd quartile: 1.44 (0.85, 2.27)
                                 4th quartile: 1.90 (1.20, 2.82)
                                 Perl pg/m3:1.14 (1.02,1.24)
                                 All trimesters adjusted simultaneously
                                 2nd quartile: 1.34 (0.79, 2.30)
                                 3rd quartile: 1.48 (0.86, 2.58)
                                 4th quartile: 1.91 (1.00,3.20)
                                 Perl pg/m3:1.14 (0.99,1.29)
    
                                 Prevalence ratios (PRs) of birth
                                 weight <3000 g during exposure over
                                 third trimester of pregnancy
                                 (adjustment for season of
                                 conception)
                                 All trimesters adjusted simultaneously
                                 Perl pg/m3:1.25 (1.04,1.50)
    
                                 Sensitivity analysisjbootstrapped  PR)
                                 2nd quartile: 0.98 (0.63,1.61); 3rd
                                 quartile: 1.22 (0.82, 2.02)
                                 4th quartile: 1.57 (1.02, 2.57)
                                 Perl |jg/m3:1.11 (0.98,1.27)
                                 Estimated increments in prevalence
                                 of birth weight of <3000 g during
                                 exposure 9 mo after birth
                                 Per 1 pg/m3: 7% (-7%, 22%)
    Reference: (Slama et al., 2007,
    0932161
    Period of Study: Jan 1998-Jan 1999
    Outcome: Birth weight offspring at term   Pollutant: PM25 absorbance (estimated)  ™ln*re(m|nt:
                                         Study Design: Cohort study
                                         Averaging Time: Entire pregnancy
                                         period and trimesters
                                                                                                                   b
                                    1st (reference) (1.29-1.61)
                                    2nd (1.61-1.72)
    December 2009
                                    E-485
    

    -------
                  Study
           Design & Methods
           Concentrations1
      Effect Estimates (95% Cl)
    Location: Munich, Germany
    N: 1016 births
    
    Statistical Analyses: Poisson model
    
    Covariates: Maternal passive smoking,
    maternal age, gestational duration, sex
    of child, parity, maternal education,
    maternal size, prepregnancy weight,
    other pollutants (PM25, PM25
    absorbance, N02), season of conception
    
    Dose-response Investigated? Yes
    
    Statistical Package: STATA
    Mean (SD): 1.76*
    
    Percentiles: 26th: 1.61*
    
    50th(Median): 1.72*
    
    75th: 1.89*
    
    Unit(i.e. ug/m3): 10-5/m
    
    Monitoring Stations:
    Spatial component: 40
    Temporal component: 1
    Copollutant (correlation):
    p.a. = pregnancy avg
    trim. = trimester
    abs = absorbance
    PM25 abs (p.a.)-PM25 abs (1st trim.):
    0.54
    PM25 abs (p.a.)-PM25 abs (2nd trim.):
    0.84
    PM25 abs (p.a.)-PM25 abs (3rd trim.):
    0.55
    PM25abs(p.a.)-PM25(p.a.):0.69
                                                                             PM25abs
                                                                             PM2.5 abs
                                                      -PM2
                                                      -PM2;
                        1st trim.): 0.68
                        2nd trim.): 0.41
                                                                             PM2.5 abs (p.a.)-PM2.5 (3rd trim.): 0.62
                                                                             PM25abs
                                                                             PM2.5 abs
                                                      -N02
                                                      -N02
                       p.a.): 0.67
                       1st trim.): 0.34
                                                                             PM2.5 abs (p.a.)-N02 (2nd trim.): 0.63
                                                                                      p.a.)-N02 (3rd trim.): 0.36
                                                                                      1sttrim.)-PM25abs(2nd
                                         PM25abs
                                         PM25abs
                                         trim.): 0.32
                                         PM25abs(1sttrim.)-PM25abs(3rd
                                         trim.): -0.26
                                         PM25abs(1sttrim.)-PM25(p.a.):0.33
                                         PM25abs 1st trim. -PM25 1st trim.):
                                         0.27
                                         PM25abs(1sttrim.)-PM25(2ndtrim.):
                                         0.08
                                         PM25abs(1sttrim.)-PM25(3rdtrim.):
                                         0.48
                                         PM25abs 1sttrim.)-N02 p.a.): 0.29
                                         PM25abs 1sttrim.)-N02 1st trim.): 0.84
                                         PM25abs(1sttrim.)-N02(2ndtrim.):
                                         0.16
                                         PM25abs(1sttrim.)-N02(3rdtrim.):-
                                         0.39
                                         PM25abs(2ndtrim.)-PM25abs(3rd
                                         trim.): 0.31
                                         PM25 abs (2nd trim.)-PM25 (p.a.): 0.48
                                         PM25abs(2ndtrim.)-PM25(1sttrim.):
                                         0.53
                                         PM25 abs (2nd trim.)-PM25 (2nd trim.):
                                         0.29
                                         PM25 abs (2nd trim.)-PM25 (3rd trim.):
                                         0.36
                                                                             PM25abs
                                                                             PM25abs
                                                                             0.19
                                                  2nd trim,
                                                  2nd trim.
                      -N02 (p.a.): 0.61
                      -N02 (1st trim.):
                                                                             PM25abs(2ndtrim.)-N02(2ndtrim.):
                                                                             0.85
                                                                             PM25abs(2ndtrim.)-N02(3rdtrim.):
                                                                             0.17
                                                                             PM25abs(3rdtrim.)-PM25(p.a.):0.52
                                                                             PM25abs(3rdtrim.)-PM25(1sttrim.):
                                                                             0.51
                                                                             PM25abs(3rdtrim.)-PM25(2ndtrim.):
                                                                             0.41
                                                                             PM25abs(3rdtrim.)-PM25(3rdtrim.):
                                                                             0.37
                                                                             PM25abs(3rdtrim.)-N02(p.a.):0.40
                                                                             PM25abs(3rdtrim.)-N02(1st
                                                                             trim.):-0.34
                                                                             PM25abs(3rdtrim.)-N02(2ndtrim.):
                                                                             0.21
                                                                             PM25abs(3rdtrim.)-N02(3rdtrim.):
                                                                             0.88
    c) 3rd (1.72-1.89)
    day) 4th (1.89-3.10)
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    the whole pregnancy
    Single-pollutant models Unadjusted
    models
    2nd quartile: 1.19 (0.74,1.99)
    3rd quartile: 1.56 (0.98, 2.50);
    4th quartile: 1.52 (0.96, 2.46)
    Per 0.5*10-5/m: 1.25 (0.90,1.70)
    Adjusted models
    2nd quartile: 1.21 (0.73,1.97)
    3rd quartile: 1.63 (0.98, 2.57);
    4th quartile: 1.78 (1.10,2.70)
    Per0.5*10-5/m: 1.45(1.06,1.87)
    
    Multipollutant models Adjusted models
    2nd quartile: 1.19 (0.70, 2.01)
    3rd quartile: 1.55 (0.80, 2.80);
    4th quartile: 1.46 (0.67, 2.90)
    Per0.5*10-5/m: 1.33(0.76, 2.38)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    the whole pregnancy (adjustment for
    season of conception)
    4th quartile: 1.72 (1.08, 2.73)
    Per 0.5*10-5/m: 1.38 (0.96,1.86)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    the whole pregnancy
    Single-pollutant models
    (Restricted analysis to PM25 below the
    median)
    Per0.5* 10-5/m: 1.67 (0.66, 3.73)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    first trimester of pregnancy
    Each trimester separately
    2nd quartile: 1.15 (0.73,1.80)
    3rd quartile: 1.01 (0.61,1.53);
    4th quartile: 1.04 (0.70,1.57)
    Per 0.5* 10-5/m: 1.03 (0.82,1.28)
    All trimesters adjusted simultaneously
    2nd quartile: 0.90 (0.52,1.58)
    3rd quartile: 0.82 (0.45,1.31);
    4th quartile: 0.88 (0.53,1.42)
    Per 0.5* 10-5/m: 1.02 (0.77,1.29)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    second trimester of pregnancy
    Each trimester separately
    2nd quartile: 1.33 (0.85, 2.22)
    3rd quartile: 1.76 (1.07, 2.91);
    4th quartile: 1.83 (1.11,2.81)
    Per 0.5* 10-5/m: 1.27 (1.04,1.54)
    All trimesters adjusted simultaneously
    2nd quartile: 1.30 (0.77, 2.16)
    3rd quartile: 1.63 (0.93, 2.73);
    4th quartile: 1.99 (1.12, 3.33)
    Per 0.5*10-5/m: 1.21 (0.93,1.54)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    third trimester of pregnancy
    Each trimester separately
    2nd quartile: 1.30 (0.85, 2.09)
    3rd quartile: 0.92 (0.55,1.50);
    4th quartile: 1.50 (1.00, 2.27)
    Per 0.5*10-5/m: 1.20 (0.98,1.44)
    All trimesters adjusted simultaneously
    2nd quartile: 0.99 (0.64,1.62)
    3rd quartile: 0.71 (0.40,1.20);	
    December 2009
                                    E-486
    

    -------
                  Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
                                                                                                                  4thquartile: 1.14(0.68,1.91)
                                                                                                                  Per0.5*10-5/m: 1.15(0.92,1.42)
    
                                                                                                                  Prevalence ratios (PRs) of birth
                                                                                                                  weight <3000 g during exposure over
                                                                                                                  first trimester of pregnancy
                                                                                                                  (adjustment for season of
                                                                                                                  conception)
                                                                                                                  All trimesters  adjusted simultaneously
                                                                                                                  4th quartile: 0.73 (0.38,1.38)
                                                                                                                  Per0.5*10-5/m: 0.93 (0.41,1.32)
    
                                                                                                                  Prevalence ratios (PRs) of birth
                                                                                                                  weight <3000 g during exposure over
                                                                                                                  second trimester of pregnancy
                                                                                                                  (adjustment for season of
                                                                                                                  conception)
                                                                                                                  All trimesters  adjusted simultaneously
                                                                                                                  4th quartile: 2.45 (1.22, 4.77)
                                                                                                                  Per0.5*10-5/m: 1.14(0.70,1.64)
    
                                                                                                                  Prevalence ratios (PRs) of birth
                                                                                                                  weight <3000 g during exposure over
                                                                                                                  third trimester of pregnancy
                                                                                                                  (adjustment for season of
                                                                                                                  conception)
                                                                                                                  All trimesters  adjusted simultaneously
                                                                                                                  4th quartile: 1.19 (0.60, 2.48)
                                                                                                                  Per0.5*10-5/m: 1.29 (0.90,1.75)
    
                                                                                                                  Sensitivity analysis (bootstrapped PR)
                                                                                                                  2nd quartile: 1.19 (0.76,1.91)
                                                                                                                  3rd quartile: 1.52 (0.99, 2.34);
                                                                                                                  4th quartile: 1.62 (1.06, 2.55)
                                                                                                                  Per0.5*10-5/m: 1.35(1.01,1.83)
                                                                                                                  Estimated increments in prevalence
                                                                                                                  of birth weight <3000 g during
                                                                                                                  exposure 9 mo after birth
                                                                                                                  Per0.5*10-5/m:18%(-16%, 57%)
    Reference: Wilhelm et al. (2005,
    0886681
    Period of Study: 1994-2000
    Location: Los Angeles County,
    California, U.S.
    Outcome: Term low birth weight (LBW)
    (<2500 g at > 37 completed wk
    gestation)
    Vaginal birth <37 completed wk
    gestation
    Pollutant: PM25 Ij*
    Averaging Time: 24 h (every 3 days) 2
    Entire pregnancy a
    Trimesters of pregnancy ^
    Months of pregnancy c
    6 wk before birth
    M Increment:
    10|jg/m3
    3 levels:
    <25 percentile (reference)
    25%-75 percentile
    2 75 percentile
                                        Age Groups: LBW: 2 37 completed wk
    
                                        Preterm births: <37 completed wk
    
                                        Study Design: Cross-sectional study
    
                                        N: For LBW: 136,134
    
                                        For preterm birth:
    
                                        106,483
    
                                        Statistical Analyses: Logistic
                                        regression
    
                                        Covariates: Maternal age, maternal
                                        race, maternal education, parity, interval
                                        since previous live birth, level of prenatal
                                        care, infant sex, previous LBW or
                                        preterm infant, birth season, other
                                        pollutants (not specified in birth weight
                                        analyses, also adjusted for gestational
                                        age)
    
                                        Dose-response Investigated? Yes
    
                                        Statistical Package: NR
                                  Mean (SD):
                                  First trimester: 21.9
                                  Third trimester: 21.0
                                  6 wk before birth: 21.0
    
                                  Range (Min, Max):
                                  First trimester: 11.8-38.9
                                  Third trimester: 11.8-.38.9
                                  6 wk before birth: 9.9-48.5
    
                                  Monitoring Stations:
                                  Zip-code-level analysis: 9
                                  Address-level analysis: 8
    
                                  Copollutant (correlation):
                                  First trimester
                                  PM25-CO:0.57
                                  PM25-N02:0.73
                                  PM25-03:-0.55
                                  PM25-PM10: 0.43
                                  Third trimester:
                                  PM25-CO:0.67
                                  PM25-N02:0.78
                                  PM25-03:-0.60
                                  PM2.5-PM10: 0.52
                                  6 wk before birth:
                                  PM25-CO:0.63
                                  PM25-N02:0.74
                                  PM25-03:-0.60
                                  PM25-PM10:0.60
                                 Incidence of LBW (third trimester
                                 exposure)
                                 <17.1|jg/m3:2.4(2.0, 2.8)
                                 17.1to<24.0|jg/m3:2.2(2.0, 2.5)
                                 > 24.0 pg/m3: 2.1 (1.7,2.4)
    
                                 Incidence of preterm birth (first
                                 trimester exposure)
                                 <18.0|jg/m3:10.6 (9.6,11.7)
                                 18.0ttx25.4fjg/rn3: 8.8 (8.1, 9.5)
                                 > 25.4 pg/m3: 9.0 (8.1,10.0)
    
                                 Incidence of preterm birth (6 wk
                                 before birth exposure)
                                 <16.5 pg/m3: 8.2 (7.4, 9.1)
                                 16.5to<24.7|jg/m3:8.8(8.2, 9.4)
                                 > 24.7 pg/m3: 9.6 (8.7, 10.5)
    
                                 Outcome: Preterm birth
                                 Exposure Period: First trimester of
                                 pregnancy
                                 Address-level analysis:
                                 Single-pollutant model: Distance Ł  1
                                 mile
                                 Per 10 pg/m3: 0.85 (0.70,1.02)
                                 18.1 to <25.2|jg/m3: 0.91 (0.72,  1.16)
                                 > 25.2 pg/m3: 0.83 (0.60,  1.14)
                                 Single-pollutant model:
                                 1 
    -------
                  Study                       Design & Methods                 Concentrations1              Effect Estimates (95% Cl)
                                                                                                                   > 25.2 pg/nf: 0.79 (0.65, 0.97)
                                                                                                                   Multipollutant modell  24.9 pg/m3: 0.76 (0.70, 0.84)
    
                                                                                                                   Zip-code-level analysis:
                                                                                                                   Single-pollutant model:
                                                                                                                   Per 10 pg/m3: 0.73 (0.67, 0.80)
                                                                                                                   18.0to<25.4|jg/m3: 0.70 (0.61, 0.80)
                                                                                                                   > 25.4 pg/m3: 0.64 (0.53, 0.76)
    
                                                                                                                   Outcome: Preterm birth
                                                                                                                   Exposure Period: 6 wk before birth
                                                                                                                   Address-level analysis:
                                                                                                                   Single-pollutant model:
                                                                                                                   Distances 1 mile
                                                                                                                   Per 10 pg/m3:1.09 (0.91,1.30)
                                                                                                                   16.8to<24.1 pg/m3:1.21 (0.97, 1.51)
                                                                                                                   a24.1 pg/m3:1.25 (0.93, 1.68)
                                                                                                                   Single-pollutant model:
                                                                                                                   1  24.5 pg/m3:1.04 (0.87, 1.24)
                                                                                                                   Single-pollutant model:
                                                                                                                   2  24.6 pg/m3:1.08 (0.99, 1.17)
    
                                                                                                                   Zip-code-level analysis
                                                                                                                   Single-pollutant model: Per 10 pg/m3:
                                                                                                                   1.10(1.00,1.21)
                                                                                                                   16.5 to <24.7|jg/m3:1.06 (0.94, 1.20)
                                                                                                                   > 24.7 pg/m3:1.19 (1.02,1.40)
                                                                                                                   (See Notes)
                                                                                                                   Multipollutant model
                                                                                                                   Per 10 pg/m3:1.12 (0.90,1.40)
                                                                                                                   > 24.6 pg/m3:1.12 (0.82, 1.52)
                                                                                                                   Notes: In the table, the 75 percentile is
                                                                                                                   noted as 24.7 pg/m3. However, the text
                                                                                                                   notes the 75 percentile as 24.3 pg/m .
    December 2009                                                    E-488
    

    -------
                  Study
           Design & Methods
           Concentrations1
      Effect Estimates (95% Cl)
    Reference: Woodruff etal. (2006,
    0887581
    
    Period of Study: 1999-2000
    
    Location: California
    Outcome (ICD10): SIDS (R95)
    
    Respiratory mortality (JOO-J99)
    
    Bronchopulmonary dysplasia (P27.1)
    
    External accidents (V01-Y98)
    
    Ill-defined and unspecified causes of
    mortality (R99)
    
    Age Groups: >28 days old
    
    Study Design: Matched case-control
    (matched on date of birth and birth
    weight)
    
    N: 3877 infants
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Maternal race, education,
    parity, age, marital status
    
    Dose-response Investigated? Yes
    
    Statistical Package: STATA
    Pollutant: PM25
    
    Averaging Time: 24 hrs (every 6 days)
    (time period between birth and post
    neonatal death for the infant who died
    and the same period for its four matched
    surviving infants)
    
    Percentiles: Infants who died of all
    causes (cases)
    
    26th: 13.4
    
    60th(Median): 19.2
    
    76th: 23.6
    
    Matched controls
    
    26th: 13.5
    
    60th(Median): 18.4
    
    76th: 22.7
    
    Monitoring Stations:
    
    73 (from 39 counties)
    PM Increment: 10|jg/m
    
    RR Estimate [Lower Cl, Upper Cl] lag:
    All-cause mortality:
    Unadjusted:  1.15 (1.00,1.32)
    Adjusted: 1.07 (0.93,1.24)
    Cause-specific mortality:
    Respiratory (all):
    Unadjusted:  2.15 (1.15, 4.02)
    Adjusted: 2.13 (1.12, 4.05)
    Respiratory (excluding deaths due to
    BPD):
    Adjusted: 1.42 (0.66, 3.03)
    Respiratory (BPD alone):
    Unadjusted:  6.00 (1.40, 27.76)
    Respiratory (low birth weight infants
    only):
    Unadjusted:  3.09 (1.14, 8.40)
    Respiratory (normal birth weight infants
    only):
    Unadjusted:  1.66 (0.74, 3.70)
    Respiratory (with matched PM25 avgd
    over all monitors in county)
    Adjusted: 2.28 (0.94, 5.52)
    Respiratory (averaging all PM25
    measurements in county  over the 2-yr
    study period):
    Adjusted: 2.26 (0.83, 6.21)
    SIDS:
    Unadjusted:  0.86 (0.61,1.22)
    Adjusted: 0.82 (0.55,1.23)
    SIDS (includes ICD10 code R99: ill-
    defined and unspecified causes of
    mortality):
    Adjusted: 1.03 (0.79, 1.35)
    External causes:
     Unadjusted: 0.91 (0.56,1.47)
    Adjusted: 0.83 (0.50, 1.39)
    Compare against the lowest quartile,
    estimates for respiratory-specific
    mortality were provided:
    2nd quartile: 1.28 (0.47, 3.51)
    3rd quartile:  1.75 (0.65, 4.72)
    4th quartile: 2.35 (0.85, 6.54)	
    December 2009
                                     E-489
    

    -------
                  Study
           Design & Methods
           Concentrations1
      Effect Estimates (95% Cl)
    Reference: Woodruff etal. (2008,
    0983861
    Period of Study: 1999-2002
    Location: U.S. counties with >250,000
    residents (96 counties)
    Outcome (ICD10): Postneonatal
    deaths: Respiratory mortality (JOOO-99,
    plus bronchopulmonary dysplasia [BPD]
    P27.1)
    SIDS (R95)
    Ill-defined causes (R99)
    All other deaths evaluated as a control
    category
    Age Groups: Infants aged >28 days
    and <1 yr
    Study Design: Cross-sectional
    N: 3,583,495 births (6,639 post neonatal
    deaths)
    Statistical Analyses: Logistic GEE
    (exchangeable correlation structure)
    Covariates: maternal race/ethnicity,
    marital status, age, education,
    primiparity, county-level poverty and per
    capita income levels, yr and month of
    birth dummy variables to account for
    time trend and seasonal effects, and
    region of the country
    sensitivity analyses performed among
    only those mothers with smoking
    information (adjustment for smoking had
    no effect  on the estimates)
    Season:  Adjusted for yr and month of
    birth dummy variables to account for
    time trend and seasonal effects
    Dose-response Investigated?
    Evaluated the appropriateness of a
    linear form from analysis based on
    quartiles of exposure and concluded that
    linear form was appropriate (data not
    shown)
    Statistical Package: SAS
    Pollutant: PM25
    Averaging Time: Measured
    continuously for 24 h once every 6 days
    exposure assigned by calculating avg
    concentration of pollutant during first 2
    mo of life
    Median and IQR (25th-75th
    percentile):
    Survivors: 14.8 (11. 7-18.7)
    All causes of death: 14.9 (12.0-18.6)
    Respiratory: 14.8 (11.5-18.5)
    SIDS: 14.5 (12.0-17.5)
    SIDS + ill-defined: 14.8 (12.1-18.5)
    Other causes: 14.9 (12.0-1 8.6)
    Percentiles: See above
    PM Component: Not assessed, but
    controlled for region of the country to
    account for PM composition variation
    Monitoring Stations: NR
    Copollutant (correlation):
    PM10(r = 0.34)
    PM25
    CO (r = 0.35)
    S02(r = 0.21)
    03(r = -
    PM Increment: IQR (7 pg/rri)
    Effect Estimate [Lower Cl, Upper Cl]:
    Adjusted ORs for single pollutant models
    All causes: 1.04 (0.98,1.11)
    Respiratory: 1.11  (0.96,1.29)
    SIDS: 1.01 (0.86, 1.20)
    Ill-defined + SIDS: 1.06 (0.97,1.17)
    Other causes: 1.03 (0.96,1.12)
    Adjusted ORs for multipollutant models
    (including CO, 03, S02)
    Respiratory: 1.05 (0.89,1.24)
    SIDS: 1.04 (0.87, 1.23)
    OR for respiratory deaths assessing
    exposure as quartiles
    Highest vs. Lowest quartile: 1.39(1.04,
    1.85)
                                                                              Notes: Monthly avg calculated if there
                                                                              were at least 3 available measures for
                                                                              PM
                                                                              Assigned exposures using the avg
                                                                              concentration of the county of residence
     All units expressed in pg/m  unless otherwise specified.
    December 2009
                                    E-490
    

    -------
    E.8. Long-Term   Exposure  and  Mortality
    Table E-30.    Long-term exposure-mortality - PMio.
                 Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: (Breitner et al., 2009,
    1884391
    Period of Study: Oct 1991-Mar 2002
    
    Location: Efurt, Germany
    Outcome: Mortality, excluding infants
    and ICD-9 > 800
    
    Study Design: Time-series
    
    Covariates: Seasonal and weekday
    variations, influenza epidemics, air
    temperature, relative humidity
    
    Statistical Analysis: Semiparametric
    Poisson regression, polynomial
    distributed lag (PDL)
    
    Statistical Package: R
    
    Age Groups: All
    Pollutant: PM10
    
    Averaging Time: Daily
    
    Mean (SD) Unit:
    
    1 (10/1/1991-8/31/1995):
    50.6 ± 32.2 pg/m3
    
    2(9/1/1995-2/28/1998):
    41.1 ±28.4|jg/m3
    
    3(3/1/1998-3/31/2002):
    24.3 + 15.4 pg/m3
    
    Total: 38.0 ±28.3 pg/m3
    
    Range (Min, Max): NR
    
    Copollutant: N02, CO, UFP
    Increment: IQR
    
    Relative Risk (96% Cl) Lag
    New City Limits
    6-day IQR: 17.2
    PDL: 0.997 (0.972-1.022)
    Mean of lags 0-5: 0.995 (0.971-1.019)
    
    Old City Limits
    6-day IQR: 17.2
    PDL: 1.004 (0.978-1.031)
    Mean of lags 0-5:1.001 (0.976-1.027)
    
    New City Limits
    15-day  IQR: 14.5
    PDL: 1.008 (0.982-1.036)
    Mean of lags 0-14:1.006 (0.981 -1.032)
    
    Old City Limits
    15-day  IQR: 14.5
    PDL: 1.019 (0.991-1.048)
    Mean of lags 0-14:1.017 (0.990-1.044)
    
    Multiday Ma, 6-day
    Overall  IQR: 24.2
    Overall  RR (95% Cl):
    0.998(0.976-1.021)
    Period 1:0.996 (0.969-1.024)
    Period 2:1.013 (0.972-1.056)
    Period 3: 0.949 (0.897-1.004)
    Multiday Ma, 15-day
    Overall  IQR: 22.3
    Overall  RR (95% Cl):
    1.020(0.993-1.093)
    Period 1:1.017 (0.984-1.051)
    Period 2:1.012 (0.973-1.071)
    Period 3: 0.978 (0.911-1.051)	
    Reference: (Slama et al, 2007,
    0932161
    Period of Study: Jan 1998-Jan 1999
    
    Location: Munich, Germany
     Outcome: Birth weight offspring at term
    
     Study Design: Cohort study
    
     N: 1016 births
    
     Statistical Analyses: Poisson model
    
     Covariates: Maternal passive smoking,
     maternal age, gestational duration, sex
     of child, parity, maternal education,
     maternal size,  prepregnancy weight,
     other pollutants (PM25, PM25
     absorbance, N02), season of conception
    
     Dose-response Investigated? Yes
    
     Statistical Package: STATA
     Pollutant: PM25 (estimated based on
     larger PM size fractions)
    
     Averaging Time: Entire pregnancy
     period and trimesters
    
      Mean (SD): 14.4
    
     Percentiles: 26th: 13.5
    
     60th(Median): 14.4
    
     76th: 15.4
    
     Monitoring Stations:
     Spatial component: 40
    
     Temporal component: 1
     Copollutant (correlation):
    
     p.a. = pregnancy avg
    
     trim. = trimester
    
     PM25(p.a.)-PM25 (1sttrim.): 0.85
    
     PM25(p.a.)-PM25 (2nd trim.): 0.77
    
     PM25(p.a.)-PM25 (3rd trim.): 0.87
    
     PM25 (p.a.)-N02 (p.a.): 0.45
    
     PM25(p.a.)-N02 (1sttrim.): 0.18
    
     PM2.5 (p.a.J-NQ, (2nd trim.): 0.32
      PM Increment:
      1) 1 pg/m3
      2) Quartiles:
      a) 1st (reference) (7.2-13.5 pg/m3)
      b) 2nd (13.5-14.4 pg/m3)
      c) 3rd (14.4-15.4 pg/m3)
      day) 4th (15.41-17.5 pg/m3)
      Prevalence ratios (PRs) of birth
      weight <3000 g during exposure over
      the whole pregnancy
      Single-pollutant models
      Unadjusted models
      2nd quartile: 1.07 (0.65,1.73); 3rd
      quartile: 1.38 (0.91, 2.09)
      4th quartile: 1.45 (0.92, 2.25)
      Perl  pg/m3:1.06 (0.95,1.19)
      Adjusted models
      2nd quartile: 1.08 (0.63,1.82); 3rd
      quartile: 1.34 (0.86, 2.13)
      4th quartile: 1.73 (1.15, 2.69); Per
      1 pg/m3:1.13 (1.00,1.29)
    
      Multipollutant models
      Adjusted models
      2nd quartile: 1.01 (0.57,1.85)
      3rd quartile: 1.12 (0.64,1.87)
      4th quartile: 1.36 (0.72, 2.45); Per
      1 pg/m3:1.07 (0.91,1.26)
    
      Single-pollutant models (restricted
    December 2009
                                   E-491
    

    -------
    Study Design & Methods
    Concentrations1
    PM2.5(p.a.)-N02 (3rd trim.): 0.37
    PM25 (1sttrim.)-PM2.5 (2nd trim.): 0.40
    Effect Estimates (95% Cl)
    Analysis to PM25 absorbance below the
    median)
    Perl ug/m3: 1.15 (0.89, 1.52)
    PM2.5 (1st trim.)-PM2.s (3rd trim.): 0.68
    PM2.5 (1st trim.)-N02 (p.a): 0.48
    PM2.5 (1st trim.)-N02 (1st trim.): 0.15
    PM2.5 (1st trim.)-N02 (2nd trim.): 0.41
    PM2.5 (1st trim.)-N02 (3rd trim.): 0.39
    PM2.5 (2nd trim.)-PM2.s (3rd trim.): 0.51
    PM2.5 (2nd trim.)-N02 (p.a): 0.23
    PM2.5 (2ndtrim.)-N02 (1st trim.): -0.03
    PM2.5 (2nd trim.)-N02 (2nd trim.): 0.17
    PM25 (2nd trim.)-N02 (3rd trim.): 0.30
    PM2.5 (3rd trim.)-N02 (p.a.): 0.39
    PM25 (3rd trim.)-N02 (1st trim.): 0.33
    PM2.5 (3rd trim.)-N02 (2nd trim.): 0.21
    PM2.5 (3rd trim.)-N02 (3rd trim.): 0.23
    PM2.s (p.a.)- PM25 absorbance (p.a.):
    nfiQ
    \j.\jy
    
    
    PM2.5 (p.a. )-PM2.5abs (1st trim.): 0.33
    PM25 (p.a.)- PM25 abs (2nd trim.): 0.48
    PM25 (p.a.)- PM25 abs (3rd trim.): 0.52
    PM25 (1st trim.)- PM25 abs (p.a.): 0.68
    PM25 (1st trim.)- PM25 abs (1st trim.):
    0.27
    
    PM25(1st trim.)- PM25abs (2nd trim.):
    0.53
    
    PM25(1st trim.)- PM25abs (3rd trim.):
    0.51
    
    PM25(2ndtrim.)-PM25abs(p.a.):0.41
    PM25(2nd trim.)- PM25abs(1st trim.):
    0.08
    
    PM2 5 (2nd trim.)- PM2 5 abs (2nd trim.):
    0.29
    PM25 (2nd trim.)- PM25 abs (3rd trim.):
    0.41
    PM25
    PM25
    0.48
    
    3rdtrim.)-PM25abs p.a.): 0.62
    3rd trim.)- PM2 5 abs 1st trim.):
    
    PM2 5 (3rd trim.)- PM2 5 abs (2nd trim.):
    0.36
    
    PM2 5 (3rd trim.)- PM2 5 abs (3rd trim.):
    0.37
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Prevalence ratios (PRs) of birth
    weight <3000 g
    Multipollutant models (simultaneous
    adjustment of 3rd trimester PM2 5 and
    whole pregnancy PM25)
    PM25 (whole pregnancy)
    Perl pg/m3: 0.96 (0.75, 1.19)
    PM2 5 (3rd trimester)
    Perl pg/m3: 1.17 (0.98, 1.40)
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    the whole pregnancy (adjustment for
    season of conception)
    4th quartile: 1.68 (1.05, 2.75); Per
    1 |jg/m3:1.12(0.97, 1.28)
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    first trimester of pregnancy
    Each trimester separately
    2nd quartile: 1.14 (0.74, 1.96); 3rd
    quartile: 1.28 (0.84, 2.10)
    4th quartile: 1.65 (1.02, 2.60)
    Perl pg/m3: 1.10 (0.99, 1.20)
    All trimesters adjusted simultaneously
    2nd quartile: 0.97 (0.60, 1.73); 3rd
    quartile: 0.98 (0.57, 1.75)
    4th quartile: 1.22 (0.71, 2.18)
    Perl pg/m3: 1.03 (0.90, 1.17)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    second trimester of pregnancy
    Each trimester separately
    2nd quartile: 0.83 (0.52, 1.32); 3rd
    quartile: 1.08 (0.71, 1.60)
    4th quartile: 0.94 (0.61, 1.47)
    Perl pg/m3:1.01 (0.92, 1.12)
    All trimesters adjusted simultaneously
    2nd quartile: 0.75 (0.46, 1.24)
    3rd quartile: 0.86 (0.56, 1.30);
    4th quartile: 0.75 (0.48, 1.23)
    Perl pg/m3: 0.94 (0.84, 1.06)
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    third trimester of pregnancy
    Each trimester separately
    2nd quartile: 1.30 (0.80, 2.17)
    3rd quartile: 1.44 (0.85, 2.27)
    4th quartile: 1.90 (1.20, 2.82)
    Perl pg/m3: 1.14 (1.02, 1.24)
    All trimesters adjusted simultaneously
    2nd quartile: 1.34 (0.79, 2.30)
    3rd quartile: 1.48 (0.86, 2.58)
    4th quartile: 1.91 (1.00,3.20)
    Perl pg/m3: 1.14 (0.99, 1.29)
                                                                                                                 Prevalence ratios (PRs) of birth
                                                                                                                 weight <3000 g during exposure over
                                                                                                                 third trimester of pregnancy
                                                                                                                 (adjustment for season of
                                                                                                                 conception)
                                                                                                                 All trimesters adjusted simultaneously
                                                                                                                 Perl pg/m3:1.25 (1.04,1.50)
    
                                                                                                                 Sensitivity analysisjbootstrapped PR)
                                                                                                                 2nd quartile: 0.98 (0.63,1.61); 3rd
                                                                                                                 quartile: 1.22 (0.82, 2.02)
                                                                                                                 4th quartile:  1.57 (1.02, 2.57)
                                                                                                                 Perl |jg/m3:1.11 (0.98,1.27)
                                                                                                                 Estimated increments in prevalence
                                                                                                                 of birth weight of <3000 g during
                                                                                                                 exposure 9 mo after birth	
    December 2009
    E-492
    

    -------
                  Study
           Design & Methods
           Concentrations1
      Effect Estimates (95% Cl)
                                                                                                                 Per 1 |jg/m°: 7% (-7%, 22%)
    Reference: (Slama et al., 2007,
    0932161
    Period of Study: Jan 1998-Jan 1999
    
    Location: Munich, Germany
    Outcome: Birth weight offspring at term
    
    Study Design: Cohort study
    
    N: 1016 births
    
    Statistical Analyses: Poisson model
    Pollutant: PM25 absorbance (estimated)
    
    Averaging Time: Entire pregnancy
    period and trimesters
    
    Mean (SD): 1.76*
    
    Percentiles: 26th: 1.61*
    PM Increment:
    1
    2
                                        Covariates: Maternal passive smoking,
                                        maternal age, gestational duration, sex   60th(Median): 1.72*
                                        of child, parity, maternal education,
                                        maternal size, prepregnancy weight,
                                        other pollutants (PM25, PM25
                                        absorbance, N02), season of conception
                                        75th: 1.89*
    
                                        Unit(i.e. ug/m3): 10-5/m
                                         Dose-response Investigated? Yes
    
                                         Statistical Package: STATA
                                        Monitoring Stations:
                                        Spatial component: 40
                                        Temporal component: 1
                                        Copollutant (correlation):
                                        p.a. = pregnancy avg
                                        trim. = trimester
                                        abs = absorbance
                                        PM25 abs (p.a.)-PM25 abs (1st trim.):
                                        0.54
                                        PM25 abs (p.a.)-PM25 abs (2nd trim.):
                                        0.84
                                        PM25 abs (p.a.)-PM25 abs (3rd trim.):
                                        0.55
                                        PM25abs(p.a.)-PM25(p.a.):0.69
                                                                             PM25abs
                                                                             PM2.5 abs
                                                      -PM2
                                                      -PM2;
                        1st trim.): 0.68
                        2nd trim.): 0.41
                                                                             PM2.5 abs (p.a.)-PM2.5 (3rd trim.): 0.62
                                                                             PM25abs
                                                                             PM2.5 abs
                                                      -N02
                                                      -N02
                       p.a.): 0.67
                       1st trim.): 0.34
                                                                             PM2.5 abs (p.a.)-N02 (2nd trim.): 0.63
                                                                             PM25abs
                                                                             PM2.5 abs
                                                  p.a.)-N02 (3rd trim.): 0.36
                                                  1sttrim.)-PM25abs(2nd
                                        trim.): 0.32
                                        PM25abs(1sttrim.)-PM25abs(3rd
                                        trim.): -0.26
                                        PM25abs(1sttrim.)-PM25(p.a.):0.33
                                        PM25abs 1st trim. -PM25  1st trim.):
                                        0.27
                                        PM25abs(1sttrim.)-PM25(2ndtrim.):
                                        0.08
                                        PM25abs(1sttrim.)-PM25(3rdtrim.):
                                        0.48
                                        PM25abs 1sttrim.)-N02  p.a.): 0.29
                                        PM25abs 1sttrim.)-N02  1st trim.): 0.84
                                        PM25abs(1sttrim.)-N02(2ndtrim.):
                                        0.16
                                        PM25abs(1sttrim.)-N02(3rdtrim.):-
                                        0.39
                                        PM25abs(2ndtrim.)-PM25abs(3rd
                                        trim.): 0.31
                                        PM25 abs (2nd trim.)-PM25 (p.a.): 0.48
                                        PM25abs(2ndtrim.)-PM25(1sttrim.):
                                        0.53
                                        PM25 abs (2nd trim.)-PM25 (2nd trim.):
                                        0.29
                                        PM25 abs (2nd trim.)-PM25 (3rd trim.):
                                        0.36
                                                                             PM25abs
                                                                             PM25abs
                                                                             0.19
                                                  2nd trim,
                                                  2nd trim.
                      -N02 (p.a.): 0.61
                      -N02 (1st trim.):
                                                                             PM25abs(2ndtrim.)-N02(2ndtrim.):
                                                                             0.85
                                                                             PM25abs(2ndtrim.)-N02(3rdtrim.):
                                                                             0.17
                                                                             PM25abs(3rdtrim.)-PM25(p.a.):0.52
                                                                             PM25abs(3rdtrim.)-PM25(1sttrim.):
                                                                             0.51
                                                                             PM25abs(3rdtrim.)-PM25(2ndtrim.):
                                                                             0.41
                                                                             PM25abs(3rdtrim.)-PM25(3rdtrim.):
                                                                             0.37
                                                                             PM25abs(3rdtrim.)-N02(p.a.):0.40
                                                                             PM25abs(3rdtrim.)-N02(1sttrim.):-
      0.5* 10-5/m
      Quartiles:
    a) 1st (reference) (1.29-1.61)
    b) 2nd (1.61-1.72)
    c) 3rd (1.72-1.89)
    day) 4th (1.89-3.10)
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    the whole pregnancy
    Single-pollutant models
    Unadjusted models
    2nd quartile: 1.19 (0.74,1.99)
    3rd quartile: 1.56 (0.98, 2.50);
    4th  quartile: 1.52 (0.96, 2.46)
    Per 0.5* 10-5/m: 1.25 (0.90,1.70)
    Adjusted models
    2nd quartile: 1.21 (0.73,1.97)
    3rd quartile: 1.63 (0.98, 2.57);
    4th  quartile: 1.78 (1.10,2.70)
    Per 0.5* 10-5/m: 1.45(1.06,1.87)
    
    Multipollutant models Adjusted models
    2nd quartile: 1.19 (0.70, 2.01)
    3rd quartile: 1.55 (0.80, 2.80);
    4th  quartile: 1.46 (0.67, 2.90)
    Per0.5*10-5/m: 1.33(0.76, 2.38)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    the whole pregnancy (adjustment for
    season of conception)
    4th  quartile: 1.72 (1.08, 2.73)
    Per 0.5* 10-5/m: 1.38 (0.96,1.86)
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    the whole pregnancy
    Single-pollutant models
    (Restricted analysis to PM25 below the
    median)
    Per 0.5* 10-5/m: 1.67 (0.66, 3.73)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    first trimester of pregnancy
    Each trimester separately
    2nd quartile: 1.15 (0.73,1.80)
    3rd quartile: 1.01 (0.61,1.53);
    4th  quartile: 1.04 (0.70,1.57)
    Per 0.5*10-5/m: 1.03 (0.82,1.28)
    All trimesters adjusted simultaneously
    2nd quartile: 0.90 (0.52,1.58)
    3rd quartile: 0.82 (0.45,1.31);
    4th  quartile: 0.88 (0.53,1.42)
    Per 0.5* 10-5/m: 1.02 (0.77,1.29)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    second trimester of pregnancy
    Each trimester separately
    2nd quartile: 1.33 (0.85, 2.22)
    3rd quartile: 1.76 (1.07, 2.91);
    4th  quartile: 1.83 (1.11,2.81)
    Per 0.5* 10-5/m: 1.27 (1.04,1.54)
    All trimesters adjusted simultaneously
    2nd quartile: 1.30 (0.77, 2.16)
    3rd quartile: 1.63 (0.93, 2.73);
    4th  quartile: 1.99 (1.12, 3.33)
    Per0.5*10-5/m:1.21 (0.93,1.54)
    
    Prevalence ratios (PRs) of birth
    weight <3000 g during exposure over
    third trimester of pregnancy
    Each trimester separately
    2nd quartile: 1.30 (0.85, 2.09)
    3rd quartile: 0.92 (0.55,1.50);
    December 2009
                                    E-493
    

    -------
                  Study
           Design & Methods
           Concentrations1
      Effect Estimates (95% Cl)
                                                                             0.34
                                                                             PM25abs(3rdtrim.)-N02(2ndtrim.):
                                                                             0.21
                                                                             PM25abs(3rdtrim.)-N02(3rdtrim.):
                                                                             0.88
                                                                             4th quartile: 1.50 (1.00, 2.27)
                                                                             Per0.5*10-5/m: 1.20 (0.98,1.44)
                                                                             All trimesters adjusted simultaneously
                                                                             2nd quartile: 0.99 (0.64,1.62)
                                                                             3rd quartile: 0.71 (0.40,1.20);
                                                                             4th quartile: 1.14 (0.68,1.91)
                                                                             Per 0.5*10-5/m: 1.15 (0.92,1.42)
    
                                                                             Prevalence ratios (PRs) of birth
                                                                             weight <3000 g during exposure over
                                                                             first trimester of pregnancy
                                                                             (adjustment for season of
                                                                             conception)
                                                                             All trimesters adjusted simultaneously
                                                                             4th quartile: 0.73 (0.38,1.38)
                                                                             Per0.5*10-5/m: 0.93 (0.41,1.32)
    
                                                                             Prevalence ratios (PRs) of birth
                                                                             weight <3000 g during exposure over
                                                                             second trimester of pregnancy
                                                                             (adjustment for season of
                                                                             conception)
                                                                             All trimesters adjusted simultaneously
                                                                             4th quartile: 2.45 (1.22, 4.77)
                                                                             Per0.5*10-5/m: 1.14(0.70,1.64)
    
                                                                             Prevalence ratios (PRs) of birth
                                                                             weight <3000 g during exposure over
                                                                             third trimester of pregnancy
                                                                             (adjustment for season of
                                                                             conception)
                                                                             All trimesters adjusted simultaneously
                                                                             4th quartile: 1.19 (0.60, 2.48)
                                                                             Per0.5*10-5/m: 1.29 (0.90,1.75)
    
                                                                             Sensitivity analysis (bootstrapped PR)
                                                                             2nd quartile: 1.19 (0.76,1.91)
                                                                             3rd quartile: 1.52 (0.99, 2.34);
                                                                             4th quartile: 1.62 (1.06, 2.55)
                                                                             Per 0.5*10-5/m: 1.35(1.01,1.83)
                                                                             Estimated increments in prevalence
                                                                             of birth weight <3000 g during
                                                                             exposure 9 mo after birth Per 0.5 * 10-
                                                                             5/m:18%(-16%, 57%)
    Reference: Wilhelm et al. (2005,
    Period of Study: 1994-2000
    
    Location: Los Angeles County,
    California, U.S.
    Outcome: Term low birth weight (LBW)
    (<2500 g at > 37 completed wk
    gestation)
    
    Vaginal birth <37 completed wk
    gestation
    
    Age Groups: LBW: 2 37 completed wk
    
    Preterm births:  <37 completed wk
    
    Study Design: Cross-sectional study
    
    N: For LBW: 136,134
    
    For preterm birth:
    
    106,483
    
    Statistical Analyses: Logistic
    regression
    
    Covariates: Maternal age, maternal
    race, maternal education, parity, interval
    since previous live birth, level of prenatal
    care, infant sex, previous LBW or
    preterm infant, birth season, other
    pollutants (not specified in birth weight
    analyses, also adjusted for gestational
    age)
    
    Dose-response Investigated? Yes
    
    Statistical Package: NR
    Pollutant: PM25
    Averaging Time: 24 h (every 3 days)
    Entire pregnancy
    Trimesters of pregnancy
    Months of pregnancy
    6 wk before birth
    
    Mean (SD):
    First trimester: 21.9
    Third trimester: 21.0
    6 wk before birth: 21.0
    
    Range (Min, Max):
    First trimester: 11.8-38.9
    Third trimester: 11.8-.38.9
    6 wk before birth: 9.9-48.5
    
    Monitoring Stations:
    Zip-code-level analysis: 9
    Address-level analysis: 8
    
    Copollutant (correlation):
    First trimester
    PM25-CO:0.57
    PM25-N02:0.73
    PM25-03:-0.55
    PM2.5-PM10: 0.43
    Third trimester:
    PM25-CO:0.67
    PM25-N02:0.78
    PM25-03:-0.60
    PM25-PM10: 0.52
    6 wk before birth:
    PM Increment:
    1)10|jg/m3
    2) 3 levels:
    a) <25 percentile (reference)
    b) 25%-75 percentile
    c) > 75 percentile
    
    Incidence of LBW (third trimester
    exposure)
    <17.1 pg/m3: 2.4 (2.0, 2.8)
    17.1to<24.0|jg/m3:2.2(2.0, 2.5)
    > 24.0 pg/m3: 2.1 (1.7,2.4)
    
    Incidence of preterm birth (first
    trimester exposure)
    <18.0|jg/m3:10.6 (9.6,11.7)
    18.0to<25.4fjg/nf:8.8(8.1,9.5)
    > 25.4 pg/m3: 9.0 (8.1,10.0)
    
    Incidence of preterm birth (6 wk
    before birth exposure)
    <16.5 pg/m3: 8.2 (7.4, 9.1)
    16.5to<24.7|jg/m3:8.8(8.2, 9.4)
    > 24.7 pg/m3: 9.6 (8.7, 10.5)
    
    Outcome: Preterm birth
    Exposure Period: First trimester of
    pregnancy
    Address-level analysis:
    Single-pollutant model:
    Distances 1 mile
    Per 10 pg/m3: 0.85 (0.70,1.02)
    18.1to<25.2|jg/m3:
    December 2009
                                    E-494
    

    -------
                  Study                       Design & Methods                  Concentrations1             Effect Estimates (95% Cl)
    
                                                                              PM25-CO:0.63                        0.91 (0.72, 1.16)
                                                                              PM25-N02: 0.74                       >25.2 pg/m3: 0.83 (0.60, 1.14)
                                                                              PM25-03: -0.60                        Single-pollutant model:
                                                                              PM25-PM10:0.60                      1  25.2 pg/m3: 0.79 (0.65, 0.97)
                                                                                                                   Multipollutant model!  24.9 pg/m3: 0.76 (0.70, 0.84)
    
                                                                                                                   Zip-code-level analysis:
                                                                                                                   Single-pollutant model:
                                                                                                                   Per 10 pg/m3: 0.73 (0.67, 0.80)
                                                                                                                   18.0to<25.4 pg/m3: 0.70 (0.61, 0.80)
                                                                                                                   > 25.4 pg/m3: 0.64 (0.53, 0.76)
    
                                                                                                                   Outcome: Preterm birth
                                                                                                                   Exposure Period: 6 wk before birth
                                                                                                                   Address-level analysis:
                                                                                                                   Single-pollutant model:
                                                                                                                   Distances 1 mile
                                                                                                                   Per 10 pg/m3:1.09 (0.91,1.30)
                                                                                                                   16.8to<24.1 pg/m3:1.21 (0.97, 1.51)
                                                                                                                   Ł24.1 pg/m3:1.25 (0.93, 1.68)
                                                                                                                   Single-pollutant model:
                                                                                                                   1  24.5 pg/m3:1.04 (0.87, 1.24)
                                                                                                                   Single-pollutant model:
                                                                                                                   2  24.6 pg/m3:1.08 (0.99, 1.17)
    
                                                                                                                   Zip-code-level analysis
                                                                                                                   Single-pollutant model:
                                                                                                                   Per 10 pg/m3:1.10 (1.00,1.21)
                                                                                                                   16.5 to <24.7|jg/m3:1.06 (0.94, 1.20)
                                                                                                                   > 24.7 pg/m3:1.19 (1.02,1.40)
    
                                                                                                                   (See Notes)
                                                                                                                   Multipollutant model
                                                                                                                   Per 10 pg/m3:1.12 (0.90,1.40)
                                                                                                                   > 24.6 pg/m3:1.12 (0.82, 1.52)
                                                                                                                   Notes: In the table, the 75 percentile is
                                                                                                                   noted as 24.7 pg/m . However, the text
                                                                                                                   notes the 75 percentile as 24.3 pg/m3.
    December 2009                                                    E-495
    

    -------
                  Study
           Design & Methods
            Concentrations1
      Effect Estimates (95% Cl)
    Reference: Woodruff etal. (2006,
    0887581
    
    Period of Study: 1999-2000
    
    Location: California
    Outcome (ICD10): SIDS (R95)
    
    Respiratory mortality (JOO-J99)
    
    Bronchopulmonary dysplasia (P27.1)
    
    External accidents (V01-Y98)
    
    Ill-defined and unspecified causes of
    mortality (R99)
    
    Age Groups: >28 days old
    
    Study Design: Matched case-control
    (matched on date of birth and birth
    weight)
    
    N: 3877 infants
    
    Statistical Analyses: Conditional
    logistic regression
    
    Covariates: Maternal race, education,
    parity, age, marital status
    
    Dose-response Investigated? Yes
    
    Statistical Package: STATA
    Pollutant: PM25
    
    Averaging Time: 24 h (every 6 days)
    (time period between birth and post
    neonatal death for the infant who died
    and the same period for its four matched
    surviving infants) Percentiles: Infants
    who died of all causes (cases)
    
    25th: 13.4
    
    60th(Median): 19.2
    
    76th: 23.6
    
    Matched controls
    
    25th: 13.5
    
    60th(Median): 18.4
    
    75th: 22.7
    
    Monitoring Stations:
    
    73 (from 39 counties)
    PM Increment: 10|jg/m
    
    RR Estimate [Lower Cl, Upper Cl] lag:
    All-cause mortality:
    Unadjusted:  1.15 (1.00,1.32)
    Adjusted: 1.07 (0.93,1.24)
    Cause-specific mortality:
    Respiratory (all):
    Unadjusted:  2.15 (1.15, 4.02)
    Adjusted: 2.13 (1.12, 4.05)
    Respiratory (excluding deaths due to
    BPD):
    Adjusted: 1.42 (0.66, 3.03)
    Respiratory (BPD alone):
    Unadjusted:  6.00 (1.40, 27.76)
    Respiratory (low birth weight infants
    only): Unadjusted: 3.09 (1.14, 8.40)
    Respiratory (normal birth weight infants
    only): Unadjusted: 1.66 (0.74, 3.70)
    Respiratory (with matched PM25 avgd
    over all monitors in county)
    Adjusted: 2.28 (0.94, 5.52)
    Respiratory (averaging all PM25
    measurements in county  over the 2-yr
    study period):
    Adjusted: 2.26 (0.83, 6.21)
    SIDS:
    Unadjusted:  0.86 (0.61,1.22)
    Adjusted: 0.82 (0.55,1.23)
    SIDS (includes ICD10 code R99: ill-
    defined and unspecified causes of
    mortality):
    Adjusted: 1.03 (0.79, 1.35)
    External causes:
    Unadjusted:  0.91 (0.56,1.47)
    Adjusted: 0.83 (0.50,1.39)
    Compare against the lowest quartile,
    estimates for respiratory-specific
    mortality were provided:
    2nd quartile: 1.28 (0.47, 3.51)
    3rd quartile:  1.75 (0.65, 4.72)
    4th quartile: 2.35 (0.85, 6.54)	
    December 2009
                                     E-496
    

    -------
                  Study
           Design & Methods
           Concentrations1
      Effect Estimates (95% Cl)
    Reference: Woodruff etal. (2008,
    0983861
    
    Period of Study: 1999-2002
    
    Location: U.S. counties with >250,000
    residents (96 counties)
    Outcome (ICD10): Postneonatal
    deaths: Respiratory mortality (JOOO-99,
    plus bronchopulmonary dysplasia [BPD]
    P27.1)
    
    SIDS (R95)
    
    Ill-defined causes (R99)
    
    All other deaths evaluated as a control
    category
    
    Age Groups: Infants aged >28 days
    and <1 yr
    
    Study Design: Cross-sectional
    
    N: 3,583,495 births (6,639 post neonatal
    deaths)
    
    Statistical Analyses: Logistic GEE
    (exchangeable correlation structure)
    
    Covariates: Maternal race/ethnicity,
    marital status, age, education,
    primiparity, county-level poverty and per
    capita income levels, yr and month of
    birth dummy variables to account for
    time trend and seasonal effects, and
    region of the country
    
    sensitivity analyses performed among
    only those mothers with smoking
    information (adjustment for smoking had
    no effect  on the estimates)
    
    Season:  Adjusted for yr and month of
    birth dummy variables to account for
    time trend and seasonal effects
    Pollutant: PM25
    
    Averaging Time: Measured
    continuously for 24 h once every 6 days
    
    Exposure assigned by calculating avg
    concentration of pollutant during first 2
    mo of life
    Median and IQR (25th-75th
    percentile):
    Survivors: 14.8 (11. 7-18.7)
    All causes of death: 14.9 (12.0-18.6)
    Respiratory: 14.8 (11.5-18.5)
    SIDS: 14.5 (12.0-17.5)
    SIDS + ill-defined: 14.8 (12.1-18.5)
    Other causes: 14.9 (12.0-1 8.6)
    Percentiles: See above
    
    PM Component: Not assessed, but
    controlled for region of the country to
    account for PM composition variation
    
    Monitoring Stations: NR
    
    Copollutant (correlation):
    
    PM,o(r = 0.34)
    
    PM25
    
    CO (r = 0.35)
    
    S02(r = 0.21)
    
    03(r = -
                                                                              Notes: Monthly avg calculated if there
                                                                              were at least 3 available measures for
                                                                              PM
    PM Increment: IQR (7 pg/rri)
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Adjusted ORs for single pollutant models
    
    All causes: 1.04 (0.98,1.11)
    
    Respiratory: 1.11  (0.96,1.29)
    
    SIDS: 1.01 (0.86, 1.20)
    
    Ill-defined + SIDS: 1.06 (0.97,1.17)
    
    Other causes: 1.03 (0.96,1.12)
    
    Adjusted ORs for multipollutant models
    (including CO, 03, S02)
    
    Respiratory: 1.05 (0.89,1.24)
    
    SIDS: 1.04 (0.87, 1.23)
    
    OR for respiratory deaths assessing
    exposure as quartiles
    
    Highest vs. Lowest quartile: 1.39(1.04,
    1.85)
                                         quartiles of exposure and concluded that
                                         linear form was appropriate (data not
                                         shown)
    
                                         Statistical Package: SAS
     All units expressed in pg/m  unless otherwise specified.
    December 2009
                                    E-497
    

    -------
    E.9. Long-Term  Exposure and  Mortality
    Table E-31.    Long-term exposure-mortality - PMio.
                Study
           Design & Methods
           Concentrations
       Effect Estimates (95% Cl)
    Reference: (Breitner et al., 2009,
    1884391
    Period of Study: Oct 1991-Mar 2002
    
    Location: Efurt, Germany
    Outcome: Mortality, excluding infants
    and ICD-9 > 800
    
    Study Design: Time-series
    
    Covariates: Seasonal and weekday
    variations, influenza epidemics, air
    temperature, relative humidity
    
    Statistical Analysis: Semiparametric
    Poisson regression, polynomial
    distributed lag (PDL)
    
    Statistical Package: R
    
    Age Groups: All
    Pollutant: PM10
    
    Averaging Time: Daily
    Mean (SD) Unit:
    1 (10/1/1991-8/31/1995):
    50.6 + 32.2 pg/m3
    2(9/1/1995-2/28/1998):
    41.1+ 28.4 pg/m3
    3 (3/1/1998-3/31/2002):
    24.3+ 15.4 pg/m3
    Total: 38.0 ±28.3 pg/m3
    Range (Min, Max): NR
    
    Copollutant: N02, CO, UFP
    Increment: IQR
    
    Relative Risk (96% Cl) lag
    New City Limits
    6-day IQR: 17.2
    PDL: 0.997 (0.972-1.022)
    Mean of lags 0-5: 0.995 (0.971-1.019)
    
    Old City Limits
    6-day IQR: 17.2
    PDL: 1.004 (0.978-1.031)
    Mean of lags 0-5:1.001 (0.976-1.027)
    
    New City Limits
    15-day IQR: 14.5
    PDL: 1.008 (0.982-1.036)
    Mean of lags 0-14:1.006 (0.981-1.032)
    
    Old City Limits
    15-day IQR: 14.5
    PDL: 1.019 (0.991-1.048)
    Mean of lags 0-14:1.017 (0.990-1.044)
    
    Multiday Ma,  6-day
    Overall IQR: 24.2
    Overall RR (95% Cl): 0.998 (0.976-
    1.021)
    Period 1:0.996 (0.969-1.024)
    Period 2:1.013 (0.972-1.056)
    Period 3: 0.949 (0.897-1.004)
    
    Multiday Ma,  15-day
    Overall IQR: 22.3
    Overall RR (95% Cl): 1.020 (0.993-
    1.093)
                                                                                                   Period 1:1.017
                                                                                                   Period 2:1.012
                                                                                0.984-1.051
                                                                                0.973-1.071
                                                                                                   Period 3: 0.978 (0.911-1.051)
    1AII units expressed in ug/m3 unless otherwise specified.
    December 2009
                                 E-498
    

    -------
    Table E-32.    Long-term exposure-mortality - PMio25.
    Study
    Reference: (Chen et al, 2005, 0879421
    Period of Study: 1973-1998
    Location: San Francisco, San Diego,
    Los Angeles, CA
    
    
    
    
    
    
    
    Reference: Goss et al. (2004, 0556241
    Period of Study: 1999-2000
    Location: United States
    
    
    
    
    
    
    Reference: Lipert et al. (2009,
    190271)
    
    Design & Methods
    Outcome: Mortality: CHD
    Study Design: Cohort
    Statistical Analyses: Cox proportion
    hazards model
    Age Groups: >25
    
    
    
    
    
    
    Outcome: Mortality
    Study Design: Cohort Study (Cystic
    Fibrosis Cohort)
    Statistical Analyses: Logistic
    Regression
    Age Groups: >6 yr
    
    
    
    Outcome: Mortality
    
    Study Design: Retrospective Cohort
    Concentrations1
    Pollutant: PM10.2.5
    Averaging Time: 25 yr
    Mean (SD): 25.4
    Range (Min, Max): NR
    Copollutant:
    N02
    03
    so.
    
    
    
    Pollutant: PM25
    Averaging Time: Annual avg
    Mean (SD) unit: PM25: 13.7 (4.2)
    
    IQR: PM25: 11.8-15.9
    Copollutant:
    03
    N02
    S02
    CO
    Pollutant: PMi0.25
    
    Mean (SD): 16.0 (5.1)
    Effect Estimates (95% Cl)
    Increment: 10 pg/m3
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    M_|.c
    Males
    PMio.25: 0.93 (0.68, 1.29)0-1
    PMi0.25+N02: 0.86 (0.62, 1.20)0-1
    PM10.25+S02: 0.90 (0.64,1. 27) 0-1
    PMi0.25+03:1.01 (0.67,1.51)0-1
    Females
    PMio.25: 1.20 (0.95, 1.53)0-1
    PMi0.25+N02: 1.19 (0.92, 1.54)0-1
    PM10.25+S02: 1.31 (1.03,1. 68) 0-1
    PMi0.25+03: 1.47 (1.10,1. 96) 0-1
    Increment: 10|jg/m3
    PM25: 1.32 (0.91-1. 93)
    
    
    
    
    
    
    
    Increment: 12
    
    1.07(1.01,1.13)
    Period of Study: 1989-1996
    
    Location: Various parts of the Untied
    States
    Statistical Analyses: Cox proportional
    hazards regression
    
    Age Groups: Male U.S. veterans
    between ages of 39 and 63 (Avg. age:
    51)
    Reference: McDonnell et al. (2000,
    0103191
    Period of Study: 1973-1977
    
    Location: California
    Outcome: Mortality
    
    Study Design: Cohort (AHSMOG
    airport cohort)
    
    Statistical Analyses: Cox regression
    models
    
    Age Groups: Males, 27 yr+
    Pollutant: PM10.25
    
    Averaging Time: Monthly avg
    
    Mean (SD): PM10.25: 27.3 (8.6)
    
    IQR: 9.7
    Copollutant:
    03: 0.70
    S02: 0.31
    N02: 0.23
    S04: 0.47
    Increment: IQR
    
    All Cause: 1.05 (0.92-1.20)
    
    Resp: 1.19 (0.88, 1.62)
    
    Lung Cancer: 1.25 (0.63-2.49)
     All units expressed in pg/m  unless otherwise specified.
    December 2009
                                   E-499
    

    -------
    Table E-33.    Long-term exposure-mortality - PIVhs (including PM components/sources).
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Abrahamowicz et al. (2003,  Outcome: Mortality: All-causes
    0862921
                                       Study Design: Case-cohort study
    Period of Study: 1982-1989
                                       Statistical Analyses: Cox proportion-
                                       Pollutant: PM25
    
                                       Averaging Time: Annual
    
                                       Mean (SD): 18.2
                                       Relative Risk (Min Cl, Max Cl)
    
                                       Estimated from graph (Fig 1): log HR
                                       for a 24.5 pg/m  increase in PM25 over
                                       time
    spline generalization
    Age Groups: >18
    Range (Min,
    Copollutant:
    Max): (9.0, 33.5)
    Sulfates
    Yr
    0:0.5 -1.1, 1.6)
    2: 0.6 0.2, 0.9)
    4: 0.6 (0.3, 0.8)
    6:0.8(0.3, 1.1)
    8: -1.0 (-1.5, 1.0)
    Reference: Abrahamowicz et al. (2003,  Outcome: Mortality: All-causes
    0862921
                                       Study Design: Case-cohort study
    Period of Study: 1982-1989
                                       Statistical Analyses: Cox proportion-
                                       Pollutant: Sulfates
    
                                       Averaging Time: Annual
    
                                       Mean (SD): 18.2
                                       Relative Risk (Min Cl, Max Cl)
    
                                       Estimated from graph (Fig 1): Log HR
                                       for a 19.9 pg/m3 increase in Sulfates
                                       overtime
    ^vwauvii. IUIWILICO na^amo inuuci IICAIUIC ic^icoo
    spline generalization
    Age Groups: >1 8
    
    
    Range (Min, Max): (9.0, 33.5)
    Copollutant: PM25
    
    
    Yr
    0:0.1 (-0.2, 0.7)
    2:0.1 (-0.2,0.4)
    4:0.0
    6:0.3
    -0.4, 0.3)
    -0.1,0.5)
    8: 0.4 (-0.4, 1.6)
    Reference: Ballester et al. (2008,
    1899771
    Period of Study: 2001-2002
    
    Location: Europe
    Outcome: Mortality-All-causes
    
    Study Design: Health Impact
    Assessment
    
    Statistical Analyses: Aphesis Network
    
    Age Groups: >30
    Pollutant: PM25
    
    Averaging Time: Annual
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    Potential Reduction in the total
    burden of mortality (min Cl, max Cl)
    for four different decreases in annual
    PMu using a conservative estimate
    Reduction to 25 pg/m3 - 0.4 (0.1, 0.8
    Reduction to 20 pg/m3 - 0.8 (0.2,1.6
    Reduction to 15 pg/m3-1.6 (0.4, 3.1)
    Reduction to 10 |jg/m3 - 3.0 (0.8, 5.8)
    Reference: Beelen et al. (2008,
    1562631
    Period of Study: 1987-1996
    
    Location: Netherlands
    Outcome: Mortality:
    
    Total (nonaccidental) (<800)
    
    Cardio-respiratory (390-448, 490-496,
    487, 480-486, 507)
    
    Pulmonary (460-519)
    
    Cardiovascular (400-440)
    
    Lung Cancer (162)
    
    Other-causes
    
    Study Design: Case-cohort study and
    prospective cohort
    
    Statistical Analyses: Cox proportion-
    hazards model
    
    Age Groups: 55-69
    Pollutant: PM25
    
    Averaging Time: Annual
    
    Mean(SD):28.3(2.1)|jg/m3
    
    Range (Min, Max): (23.0, 36.8)
    
    Copollutant (correlation):
    
    N02: (>0.8)
    
    BS: (>0.8)
    
    S02: (>0.6)
    Increment: 11 pg/m
    
    Relative Risk (Min Cl, Max Cl)
    RR for the association between
    exposures to PM25 and cause
    specific mortality
    Natural Cause:
    Full cohort: 1.06 (0.97,1.16)
    Case cohort: 0.86 (0.66,1.13)
    Cardiovascular:
    Full cohort: 1.04 (0.90,1.21)
    Case cohort: 0.83 (0.60,1.15)
    Respiratory:
    Full cohort: 1.07 (0.75,1.52)
    Case cohort: 1.02 (0.56,1.88)
    Lung Cancer: Full cohort: 1.06 (0.82,
    1.38)
    Case cohort: 0.87 (0.52,1.47)
    Other cause: F
    Ull cohort: 1.08 (0.96,1.23)
    Case cohort: 0.85 (0.65,1.12)
    
    RR for the association between
    exposures to BS and cause specific
    mortality
    Natural Cause:
    Full cohort: 1.05 (1.00,1.11)
    Case cohort: 0.97 (0.83,1.13)
    Cardiovascular: Full cohort: 1.04 (0.95,
    1.13)
    Case cohort: 0.98 (0.81,1.18)
    Respiratory:
    Full cohort: 1.22 (0.99,1.50)
    Case cohort: 1.29 (0.91,1.83)
    Lung Cancer:
    Full cohort: 1.03 (0.88,1.20)
    Case cohort: 1.03 (0.77,1.38)
    Other cause:
    Full cohort: 1.04 (0.97,1.12)
    Case cohort: 0.91 (0.78,1.07)	
    December 2009
                                    E-500
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Breitner et al. (2009,
    1884391
    
    Period of Study: Oct 1991-Mar 2002
    
    Location: Efurt, Germany
    Outcome: Mortality, excluding infants
    and ICD-9 > 800
    
    Study Design: Time-series
    
    Covariates: Seasonal and weekday
    variations, influenza epidemics, air
    temperature,  relative humidity
    
    Statistical Analysis: Semiparametric
    Poisson regression, polynomial
    distributed lag (PDL)
    
    Statistical Package: R
    
    Age Groups: All
    Pollutant: PM25
    
    Averaging Time: Daily
    Mean (SD) Unit:
    1 (10/1/1991-8/31/1995):
    50.6 + 32.2 pg/m3
    2(9/1/1995-2/28/1998):
    41.1+ 28.4 pg/m3
    3 (3/1/1998-3/31/2002):
    24.3+ 15.4 pg/m3
    Total: 38.0 ±28.3 pg/m3
    Range (Min, Max): NR
    
    Copollutant: N02, CO, UFP
    Increment: IQR
    
    Relative Risk (96% Cl) lag
    New City Limits
    6-day IQR: 13.3
    PDL: 1.009 (0.984-1.035)
    Mean of lags 0-5:1.004 (0.981-1.027)
    
    Old City Limits
    6-day IQR: 13.3
    PDL: 1.017 (0.990-1.044)
    Mean of lags 0-5:1.010 (0.986-1.035)
    
    New City Limits
    15-day IQR: 11.5
    PDL: 1.019 (0.988-1.050)
    Mean of lags 0-14:1.017 (0.992-1.042)
    
    Old City Limits
    15-day IQR: 11.5
    PDL: 1.030 (0.997-1.063)
    Mean of lags 0-14:1.025 (0.999-1.052)
    
    Multiday Ma,  6-day
    Overall IQR:  13.3
    Overall RR (95% Cl):
    1.004(0.981-1.027)
    Period 1:NR
    Period 2:1.017 (0.990-1.044)
    Period 3: 0.974 (0.937-1.013)
    
    Multiday Ma,  15-day
    Overall IQR:  11.5
    Overall RR (95% Cl):
    1.017(0.992-1.042)
    Period 1:NR
    Period 2:1.016 (0.988-1.045)
    Period 3:1.016 (0.971-1.063)	
    December 2009
                                    E-501
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Brunekreef et al. (2009,
    1919471
    
    Period of Study: 1987-1996
    
    Location: The Netherlands
    Outcome: All cause mortality (ICD-9
    400-440, 460-519, > 800)
    
    Study Design: Case-cohort
    Pollutant: PM25, estimated from PM10
    levelsf
                                        Covariates:
                                        Individual: sex, age, Quetelet index,
                                        smoking status, passive smoking
                                        status, educational level, occupation,
                                        occupational exposure, marital status,
                                        alcohol use, intake of vegetables, fruits,  |\|o2: 0.75
                                        energy, saturatured and
                                        monounsaturated fatty acids, trans fatty  BS: 0.84
                                        acids, total fiver, folic acid and fish
    Averaging Time: 24 h
    
    60th Percentile: 28 pg/m3
    
    Range (Min, Max): 23-37
    
    Copollutant (correlation):
                                        Area-level: Percent of population with
                                        income below the 40th percentile and
                                        above the 80th percentile
    
                                        Statistical Analysis: Cox proportional
                                        hazards
    
                                        Statistical Package: State, SPSS, R
    
                                        Age Groups: 120,000 adults aged
                                        55-69 yr at enrollment
                                        NO: 0.69
    
                                        SO,: 0.43
    Increment: 10|jg/m
    
    Relative Risk (96 % Cl) for PM2 5
    concentrations and cause specific
    mortality
    Case Cohort
    Natural Cause: 0.86 (0.66-1.13)
    Cardiovascular: 0.83 (0.60-1.15)
    Respiratory: 1.02 (0.56-1.88)
    Lung Cancer: 0.87 (0.52-1.47)
    Noncardiopulmonary, non-lung cancer:
    0.85(0.65-1.23)
    Full Cohort
    Natural Cause: 1.06 (0.97-1.16)
    Cardiovascular: 1.04 (0.90-1.21)
    Respiratory: 1.07 (0.75-1.52)
    Lung Cancer: 1.06(0.82-1.38)
    Noncardiopulmonary, non-lung cancer:
    1.08(0.72-1.19)
    Relative Risk (96%CI) for PM2.s
    concentrations and cause specific
    mortality in full cohort analysis by
    confounder model
    Natural Cause Mortality
    Unadjusted: 1.11 (1.04-1.20)
    Smoking: 1.04 (0.96-1.13)
    Smoking, area-level income:
    1.06(0.97-1.16)
    Cardiovascular Mortality
    Unadjusted: 1.09 (0.97-1.23)
    Smoking: 1.02 (0.90-1.16)
    Smoking, area-level income:
    1.04(0.90-1.21)
    Respiratory Mortality
    Unadjusted: 1.23 (0.92-1.65)
    Smoking: 1.10 (0.81-1.50)
    Smoking, area-level income:
    1.07(0.75-1.52)
    Lung Cancer Mortality
    Unadjusted: 1.17 (0.95-1.46)
    Smoking: 1.06 (0.85-1.33)
    Smoking, area-level income:
    1.06(0.82-1.38)
    Noncardiopulmonary, Non-Lung Cancer
    Mortality
    Unadjusted: 1.10 (1.00-1.22)
    Smoking: 1.05 (0.94-1.16)
    Smoking, area-level income:
    1.08(0.96-1.22)    	
    Reference: Chen et al. (2005, 0879421  Outcome: Mortality: CHD
    
    Period of Study: 1973-1998           Study Design: Cohort
    Location: San Francisco, San Diego,
    Los Angeles, CA
    Statistical Analyses: Cox proportion
    hazards model
    
    Age Groups: >25
    Pollutant: PM25
    
    Averaging Time: 25 yr
    
    Mean (SD): 29.0
    
    Range (Min, Max): NR
    
    Copollutant: N02, 03, S02
    Increment: 10|jg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Males
    PM25: 0.89 (0.69, 1.17)0-1
    PM25+N02: 0.82 (0.61, 1.10); 0-1
    PM25+S02:  0.86 (0.65,1.14) 0-1
    PM25+03: 0.92 (0.65,1.29) 0-1
    
    Females
    PM25:1.19 (0.96, 1.47)0-1
    PM25+N02:1.18 (0.95, 1.47); 0-1
    PM25+S02:1.36 (1.05,1.74) 0-1
    PM25+03:1.61 (1.17,2.22) 0-1
    December 2009
                                     E-502
    

    -------
                  Study
                                               Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Eftim et al. (2008, 0991041   Outcome (ICD-9): All nonaccidental
                                        causes(<8001
    Period of Study: 2000-2002                  v     '
    Location: USA, Same cities as six
    cities and ACS cohorts
                                        Study Design: Cross-sectional
    
                                        Statistical Analyses: Log-linear
                                        regression, Poisson
    
                                        Age Groups: >65
    Pollutant: PM25
    
    Averaging Time: Annual avg
    
    Mean (SD): |
    
    ACS:  13.6 (2.8)
    
    SCS:  14.1 (3.1)
    
    Range (Min, Max):
    ACS:  (6.0, 25.1); SCS: (9.6, 19.1)
    Increment: 10 pg/m
    
    % Increase in Mortality for overall
    exposure period and individual yr
    (96%CI Min, 96%CI Max):
    ACS (adjusted for age, sex)
    Overall: 10.8 (8.6,13.0)
    2000:10.9(7.3, 14.6)
    2001:9.1 (5.3, 12.7)
    2002:10.1(6.0,14.3)
    
    SCS (adjusted for age, sex)
    Overall: 20.8 (14.8, 27.1)
    2000:17.8 (9.8, 26.4)
    2001:16.5  7.4, 25.0
    2002:33.5(19.2,49.3)	
    Reference: Enstrom et al. (2005,
    0873561
    
    Period of Study: 1973-2002
    
    Location: 25 California Colonies
                                        Outcome: Mortality: Cardiovascular-
                                        respiratory (390-448)
    
                                        (480-486, 487, 490-496, 507)
    
                                        Study Design: Retrospective cohort
    11 California Colonies (EPA IPN study)   Statistical Analyses: Cox proportional
                                        hazards regression model, SAS
                                        PHREG
    
                                        Age Groups: 35 or older
    Pollutant: PM25
    
    Averaging Time: Annual
    
    Mean (SD): 23.4
    
    Range (Min, Max): (13.1 pg/m3, 36.1)
    Relative Risk (Lower Cl, Upper Cl)
    
    RR from causes for both sexes by
    county from 1973-2002
    Alameda: 0.962 (0.926,0.999)
    Butte: 0.999 (0.910,1.096)
    Contra Costa: 0.999 (0.943,1.058)
    Fresno: 0.935 (0.872,1.002)
    Humboldt: 0.992 (0.900,1.092)
    Kern: 0.944 (0.872,1.023)
    Marin: 0.939 (0.867,1.016)
    Napa: 0.949 (0.868,1.038)
    Orange: 0.990 (0.948,1.034)
    Riverside: 0.959 (0.906,1.015)
    Sacramento: 0.998 (0.944,1.055)
    San Bernardino: 0.992 (0.938,1.049)
    San Diego: 0.992 (0.954,1.033)
    San Francisco: 0.963 (0.914,1.014)
    San Joaquin: 0.925 (0.816,1.049)
    San Mateo: 0.949 (0.899,1.003)
    Santa Barbara: 0.968 (0.878,1.068)
    Santa Clara: 0.955 (0.910,1.003)
    Santa Cruz: 0.890 (0.793,0.999)
    Solano: 0.901  (0.815,0.995)
    Sonoma: 0.968 (0.884,1.060)
    Stanislaus: 0.984 (0.904,1.072)
    Tulare: 1.047 (0.979,1.119)
    Ventura: 0.967 (0.872,1.072)
    
    RR from all causes for 11 counties
    for both sexes (EPA IPN study)
    Santa Barbara: 0.968 (0.878,1.068)
    Contra Costa: 0.999 (0.943,1.058)
    Alameda: 0.962 (0.926,0.999)
    Butte: 0.999 (0.910,1.096)
    San Francisco: 0.963 (0.914,1.014)
    Santa Clara: 0.955 (0.910,1.003)
    Fresno: 0.935 (0.872,1.002)
    San Diego: 0.992 (0.954,1.033)
    Kern: 0.944 (0.872,1.023)
    Riverside: 0.959 (0.906,1.015)
    Reference: Filleul et al. (2005, 0873571  Outcome: Nonaccidental causes
                                        (<800), cardiopulmonary disease (401-
                                        440 and 460-519), lung cancer (162)
    Period of Study: 1974-1976
    
    Location: 7 cities in France
                                        Age Groups: 25-59 yr
    
                                        Study Design: Cohort
    
                                        N: 14,284 people
    
                                        Statistical Analyses: Cox proportional
                                        hazard, regression
    
                                        Covariates: Sex, smoking habits,
                                        educational level, body-mass index
                                        (BMI), occupational exposure
    
                                        Statistical Package: Proc Phreg SAS
    Pollutant: Total suspended particles
    (TSP)
    
    Averaging Time: NR
    
    Mean (SD): NR
    
    Range (Min, Max): (45, 243)
    
    PM Component: NR
    
    Monitoring Stations: 1 station
    Copollutant (correlation):
    BS r = 0.87
    S02r = 0.17
    NO r = 0.84
    N02r = 0.60
    Increment: 10|jg/m
    
    Adjusted mortality rate ratios: 24 areas:
    All nonaccidental causes:
    1.00[0.99,1.01]
    
    Lung cancer: 0.97[0.94,1.01]
    
    Cardiopulmonary disease:
    1.01 [0.99,1.03]
    
    18 areas: All nonaccidental causes:
    1.05[1.02,  1.08]
    
    Lung cancer: 1.00[0.92,1.10]
    
    Cardiopulmonary disease:
    1.06[1.01,1.12]
    December 2009
                                                                        E-503
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Fuentes et al. (2006,
    0976471
    
    Period of Study: Jun 2000
    
    Location: Conterminous U.S.
    Outcome: Mortality:
    
    Study Design: Time-series
    
    Statistical Analyses: Generalized
    Poisson Regression
    
    Age Groups: 0-14,15-64,  >65
    
    Covariates: Temperature,  pressure,
    dew point, wind speed, elevation, age,
    ethnicity
    Pollutant: PM25
    
    Averaging Time: Monthly
    
    Mean (SD): 6.60 (0.76)
    
    Copollutant: PMi0, 03
    Increment: 10|jg/m
    
    PM25:1.066 (1.064, 1.069)
    
    PM10:1.030 (1.028, 1.032)
    Reference: Janes et al. (2007, 0909271
    
    Period of Study: 2000-2002
    
    Location: 113 U.S. counties
    Outcome: Mortality:
    
    Study Design: Time-series
    
    Statistical Analyses: Cox proportional
    hazards model
    
    Age Groups: 65-74
    
    75-84
    
    85+
    Pollutant: PM25
    
    Averaging Time: Annual avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    Increment: 1 pg/m
    % Increase (Lower Cl, Upper Cl) lag:
    Overall % Increase by age-sex stratum
    Age Category
    65-74: Male: 1.48 (0.93,2.03)
    Female: 0.83 (0.24,1.43)
    75-84: Male: 0.85 (0.34,1.35)
    Female: 0.77 (0.28,1.27)
    85+:  Male: 0.70 (0.03,1.38)
    Female: 0.59 (0.05,1.12)
    National Trend % Increase by age-sex
    stratum
    Age Category
    65-74: Male: 3.55 (2.77,4.34)
    Female: 1.97 (1.12,2.83)
    75-84: Male: 2.48 (1.83,3.14)
    Female: 2.29 (1.66,2.93)
    85+:  Male: 1.38 (0.52,2.26)
    Female: 1.65 (1.01,2.29)
    Local Trend % Increase by age-sex
    stratum
    Age Category
    65-74: Male: 0.04 (-0.58,0.67)
    Female:-0.03 (-0.71,0.66)
    75-84: Male:-0.34 (-0.87,0.19)
    Female:-0.31 (-0.82,0.21)
    85+:  Male: <0.01 (-0.71,0.73)
    Female: -0.22 (-0.74,0.31)
    'Local trends are county specific
    deviations from national trends
    Reference: Jerrett et al. (2003,
    0873801
    
    Period of Study: 1982
    
    Location: 151 cities from ACS
    Outcome: Mortality
    
    Study Design: Multilevel, individual-
    ecologic analysis
    
    Statistical Analysis: Cox proportional
    hazards model
    
    Covariates: Smoking, education,
    occupational exposures, BMI, marital
    status, alcohol consumption, gender
    Pollutant: Sulfates
    
    Mean (SD): 10.6
    
    Range (Min, Max): 3.6,23.5
    Increment: 19.9 (Range)
    All Cause: S04:1.17 (1.07,1.27)
    S04 +CO: 1.16 (1.10, 1.23)
    S04 + N02:1.16 (1.08, 1.24)
    S04 + 03:1.17 (1.11,1.24)
    S04 + S02:1.05 (0.98, 1.12)
    CPD:S04:1.25 (1.16, 1.35)
    S04+ 00:1.28(1.18, 1.39)
    S04 + N02:1.29 (1.17, 1.42)
    S04 + 03:1.27 (1.17, 1.38)
    S04 + S02:1.13 (1.03, 1.24)
    
    Lung Cancer: S04:1.31 (1.09,1.58)
    S04+ 00:1.26(1.03, 1.53)
    S04 + N02:1.31 (1.05, 1.65)
    S04 + 03:1.30 (1.07, 1.59)
    S04 + S02:1.37 (1.08, 1.73)
    December 2009
                                    E-504
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Jerrett et al. (2005,
    0876001
    Period of Study: 1982-2000
    
    Location: Los Angeles, California
    Outcome: Mortality: Non- accidental
    (<800)
    
    IHD (410-414)
    
    Cardiopulmonary (400-440, 460-519)
    
    Lung Cancer (162)
    
    OtherCancers (140-149,160,161,163-
    239)
    
    Other causes
    
    Study Design: Retrospective Cohort
    
    Statistical Analyses: Cox regression
    hazards model
    
    kriging, radial basis function
    multiquadric interpolator
    
    Age Groups: All ages
    Pollutant: PM25
    
    Averaging Time: Annual avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    
    Copollutant: 03
    Increment: 10|jg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    All Causes-PM2 5 Only:
    1.24(1.11,1.37)
    44 Ind. Covariatestogether+PM25:
    1.17(1.03,1.32)
    44 Ind. Covariatestogether PM25+03:
    1.20(1.07,1.34)
    44 Ind. Covariates together+intersection
    within freeways within 500 m+
    PM25+03:1.17 (1.05,1.31)
    IHD-PM25 Only: 1.49 (1.20,1.85)
    44 Ind. Covariates together+PM25:
    1.39(1.12,1.73)
    44 Ind. Covariates together+PM25+03:
    1.45(1.15,1.82)
    44 Ind. Covariates together+intersection
    within freeways within 500 m+
    PM25+03:1.38 (1.11,1.72)
    Cardiopulmonary - PM25 Only:
    1.20(1.04,1.39)
    44 Ind. Covariates together PM25+03:
    1.19(1.02,1.38)
    44 Ind. Covariates together+intersection
    within freeways within 500 m+
    PM25+03:1.13 (0.97,1.31)
    Lung Cancer-PM25 Only: 1.60
    (1.09,2.33)
    44 Ind. Covariates together+PM25:
    1.44(0.98,2.11)
    44 Ind. Covariates together+intersection
    within freeways within 500 m+
    PM25+03:1.46 (0.99,2.16)
    Other Cancers-PM2 5 Only:
    1.09(0.85,1.40)
    44 Ind. Covariates together PM25+03:
    1.08(0.83,1.39)
    44 Ind. Covariates together+intersection
    within freeways within 500 m+
    PM25+03:1.08 (0.83,1.39)
    All Other Causes - PM2 5 Only:
    1.11 (0.74,1.67)
    44 Ind. Covariates together PM25+03:
    0.95(0.64,1.39)
    44 Ind. Covariates together+intersection
    within freeways within 500 m+
    PM25+03:1.02 (0.71,1.48)	
    December 2009
                                    E-505
    

    -------
                  Study
           Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Reference: Laden et al. (2006, 0876051
    
    Period of Study: 1974-1998
    
    Period 1:1974-1989
    
    Period 2:1990-1998
    
    Location: Nine U.S. Cities
    
    Watertown,  MA
    
    Kingston, TN
    
    Harriman, TN
    
    St. Louis, MO
    
    Steubenville, OH
    
    Portage, Wl
    
    |Wyocena, Wl
    
    Pardeeville, Wl
    
    Topeka, KS
    Outcome: Total mortality
    
    Nonaccidental (<800)
    
    Cardiovascular (400-440)
    
    Respiratory (485-496)
    
    Lung Cancer (162)
    
    Other
    
    Study Design: Prospective Cohort
    
    Statistical Analyses: Cox proportional
    hazards regression
    
    Age Groups: 25-74
    Pollutant: PM25
    
    Averaging Time: Annual avg
    Mean (SD):
    Period 1
    Portage: 11.4
    Topeka: 12.4
    Watertown: 15.4
    Harriman:  20.9
    St Louis: 19.2
    Steubenville: 29.0
    Period 2
    Portage: 10.2
    Topeka: 13.1
    Watertown: 12.1
    Harriman:  18.1
    St. Louis: 13.4
    Steubenville: 22.0
    Increment: 10|jg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    lag:
    Period 1:
    Portage: 1.00
    Topeka: 1.06 (0.86,1.31)
    Watertown: 1.06 (0.87,1.28)
    Harriman:  1.19 (0.98,1.44)
    St Louis: 1.15 (0.96, 1.38)
    Steubenville: 1.31 (1.10,1.57)
    Period 2:
    Portage: NR
    Topeka: 1.01 (0.83,1.22)
    Watertown: 0.82 (0.67,1.00)
    Harriman:  1.10 (0.91,1.33)
    St Louis: 0.96 (0.80, 1.15)
    Steubenville: 1.06 (0.89,1.27)
    Complete Period:
    Portage: 1.00
    Topeka: 1.03 (0.89,1.19)
    Watertown: 0.95 (0.83,1.08)
    Harriman:  1.15 (1.01,1.32)
    St. Louis: 1.05 (0.93, 1.20)
    Steubenville: 1.18 (1.04,1.34)
    RR for complete follow up avg PIVhs
    Total Mortality: 1.16 (1.07,1.26)
    Cardiovascular: 1.28 (1.13,1.44)
    Respiratory: 1.08 (0.79,1.49)
    Lung Cancer: 1.27 (0.96,1.69)
    Other: 1.02 (0.90,1.17)
    RR for Period 1 avg PMu
    Total Mortality: 1.18 (1.09,1.27)
    Cardiovascular: 1.28 (1.14,1.43)
    Respiratory: 1.21  (0.89,1.66)
    Lung Cancer: 1.20 (0.91,1.58)
    Other: 1.05 (0.93,1.19)
    Decrease  in avg PIVh.s over the 2
    periods
    Total Mortality: 0.73 (0.57, 0.95)
    Cardiovascular: 0.69 (0.46,1.01)
    Respiratory: 0.43 (0.16,1.13)
    Lung Cancer: 1.06 (0.43, 2.62)
    Other: 0.85 (0.56,1.27)	
    Reference: Lipfert et al. (2006, 0887561
    
    Period of Study: 1989-1996
    
    Location: Various parts of the Untied
    States
    Outcome: Mortality
    
    Study Design: Retrospective Cohort
    
    Statistical Analyses: Cox proportional
    hazards regression
    
    Age Groups: Male U.S. veterans
    between ages of 39 and 63 (Avg. age:
    51)
    Pollutant: Sulfate
    
    Mean (SD) from 1976-81:10.7 (3.6)
    Increment: 8
    
    1.045(0.944, 1.157)
    Reference: Lipfert et al. (2006, 0887561
    
    Period of Study: 1989-1996
    
    Location: Various parts of the Untied
    States
    Outcome: Mortality
    
    Study Design: Retrospective Cohort
    
    Statistical Analyses: Cox proportional
    hazards regression
    
    Age Groups: Male U.S. veterans
    between ages of 39 and 63 (Avg age
    51)
    Pollutant: PM25
    
    Mean (SD): 14.3 (3.2)
    Increment: 8
    
    1.118(1.038,1.203)
    December 2009
                                     E-506
    

    -------
                 Study
    Design & Methods
    Concentrations1
    Effect Estimates (95% Cl)
    Reference: Lipfert et al. (2006, 0882181  Outcome: Mortality: Non- accidental
    
    Period of Study: 1997-2002           ^   '
                                      Study Design: Retrospective cohort                             ,
    Location: Various parts of the Untied                                      Mean (SD): 15.02 (4.80) pg/m3 (2000-
    States                             Statistical Analyses: Cox proportional  2003)
                               Pollutant: PM25
    
                               Averaging Time: Annual avg
                              Increment: 10|jg/m
    
                              % Increase per 10 ug/m increase in
                              PM2.s
                              Single-Pollutant Model
                              As: -5.23%
    AIC
    
    Age Groups: Male U.S. veterans
    between ages of 39 and 63 (Avg. age:
    51)
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Range (Min, Max): (3.29, 24.96)
    Copollutant (correlation):
    As: r = 0.443
    Cr:r = 0.379
    Cu:r = 0.530
    
    Fe:r = 0.379;
    
    Pb:r = 0.489
    Mn:r = 0.389;
    Ni:r = 0.140
    
    Se:r = 0.312;
    V:r = 0.197
    Zn: r = 0.420;
    
    OC:r = 0.620
    
    EC: r = 0.544; |
    
    S04:r = 0.827
    N03:r = 0.649
    N02:r = 0.641
    Peak CO: r = 0.040
    Peak 03:r = 0.222
    Peak S02:r = 0.714
    
    
    
    
    
    
    
    Cu:2.12%
    Fe:2.81%
    Pb: -2.40%
    Mn:-1.20%
    Ni: 3.75%
    Se: -0.30%
    V: 5.08%
    Zn: 1.52%
    OC: -0.02%
    EC' 9 16%
    S04: 3.04%
    N03: 6.60%
    N02: 6.92%
    Peak CO: -0.61%
    Peak 03: 4.95%
    PeakS02:-4.20%
    Multiple Pollutants model- Pollutant
    with traffic density
    N03: 3.42%
    S04: -2.73%
    EC: 6.27%
    Ni:2.51%
    V: 3.27%
    
    Pollutant with NO;
    EC: 5.93%
    Ni:2.31%
    . . 0
    Pollutant with Peak Oi
    Traffic density: 2.40%
    EC: 10.79%
    Fe: 5.94%
    N03: 7.57%
    PM2 5:8.97%
    V: 4.93%
    Ni: 3.65%
    S04: 6.75%
    Cu: 1.55%
    OC:0.21%
    December 2009
                            E-507
    

    -------
                  Study
           Design & Methods
            Concentrations1
                                          Effect Estimates (95% Cl)
    Reference: Krewski et al. (2009,
    1911931
    
    Period of Study: 1979-2000
    
    Location: 48 contiguous states U.S.
    Outcome: Death
    
    Study Design: Cohort
    
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
    
    Statistical Analysis: Cox proportional-
    hazards model
    
    Statistical Package: NR
    
    Age Groups: Adults of at least 30 yr
    Pollutant: PM25
    
    Averaging Time: NR
    
    Mean Unit:
    
    1979-1983: 21.20 pg/m3
    
    1999-2000:14.02 pg/m3
    
    Range (Min, Max):
    
    1979-1983:10.77-30.01
    
    1999-2000:5.80-22.20
    
    Copollutant:
    
    S042", S02, PM15, TSP, 03, N02, CO
                                       Increment: 10|jg/m
    
                                       Hazard Ratio (96% Cl)
                                       MSA&DIFF
                                       Increment Change:
                                       10.78(1.043-1.115}
                                       Change 5-15 pg/m
                                       1.128(1.077-1.183)
                                       Change 10-20 pg/m3:
                                       1.079(1.048-1.112)
                                       HR(96%CI)
                                       Los Angeles
                                       Parsimonious ecologic covariates:
                                       1.126(1.014-1.251)
                                       HR(96%CI)
                                       16-yr time window
                                       GroupA: 0.98 (0.92-1.06)
                                       Group B: 1.01 (0.99-1.02)
                                       HR(96%CI)
                                       Third follow-up, 7 Ecologic Variables
                                                                                                             1979-1983:1.044
                                                                                                             1999-2000:1.057
                                                                                          1.028-1.060
                                                                                          1.036-1.079
                                                                                                             HR(96%CI)
                                                                                                             Nationwide analysis, 1999-2000
                                                                                                             Standard Cox: 1.03 (1.01-1.05)
                                                                                                             Random Effects Cox: 1.06 (1.04-1.0
                                                                                                             Increment: 1.5|jg/m3
                                                                                                             HR(96%CI)
                                                                                                             28 County, 3-yr model
                                                                                                             All 7 ecologic covariates:
                                                                                                             0.977(0.932-1.025)	
    Reference: Krewski et al. (2009,
    1911931
    
    Period of Study: 1979-2000
    
    Location: 48 contiguous states U.S.
    Outcome: Death from cardiopulmonary  Pollutant: PM25
    disease                                   .
                                       Averaging Time: NR
    Study Design: Cohort
                                       Mean Unit:
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
                                       Statistical Analysis: Cox proportional-
                                       hazards model
    
                                       Statistical Package: NR
    
                                       Age Groups: Adults of at least 30 yr
    1979-1983:21.2
    
    1999-2000:14.02 pg/m3
    
    Range (Min, Max):
    
    1979-1983:10.77-30.01
    
    1999-2000:5.80-22.20
    
    Copollutant:
    
    S042", S02, PM15, TSP, 03, N02, CO
                                       Increment: 10|jg/m
    
                                       Hazard Ratio (96% Cl)
                                       MSA&DIFF
                                       Increment Change: 1.078 (1.077-1.182)
                                       Change 5-15 pg/m3:
                                       1.208(1.132-1.290)
                                       Change 10-20 pg/m3:
                                       1.127(1.081-1.174)
                                       HR(96%CI)
                                       Los Angeles
                                       Parsimonious ecologic covariates:
                                       1.086(0.939-1.285)
                                       HR(96%CI)
                                       16-yr time window
                                       Group A: 1.00 (0.90-1.11)
                                       Group 6:1.05(1.03-1.07)
                                       HR(96%CI)
                                       Third follow-up, 7 Ecologic Variables
                                       1979-1983:1.094(1.070-1.118)
                                       1999-2000:1.138  1.106-1.172)
                                       HR(96%CI)
                                       Nationwide analysis, 1999-2000
                                       Standard Cox: 1.09 (1.06-1.12)
                                       Random Effects Cox: 1.13(1.10-1.16)
                                       Increment: 1.5|jg/m3
                                       HR(96%CI)
                                       28 County, 3-yr model
                                       All 7 ecologic covariates: 0
                                       .940(0.875-1.011)	
    December 2009
                                   E-508
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Krewski et al. (2009,
    1911931
    
    Period of Study: 1979-2000
    
    Location: 48 contiguous states U.S.
    Outcome: Death from ischemic heart
    disease
    
    Study Design: Cohort
    
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
    
    Statistical Analysis: Cox proportional-
    hazards model
    
    Statistical Package: NR
    
    Age Groups: Adults of at least 30 yr
    Pollutant: PM25
    
    Averaging Time: NR
    
    Mean Unit:
    
    1979-1983: 21.20 pg/m3
    
    1999-2000:14.02 pg/m3
    
    Range (Min, Max):
    
    1979-1983:10.77-30.01
    
    1999-2000:5.80-22.20
    
    Copollutant:
    
    S042", S02, PM15, TSP, 03, N02, CO
    Increment: 10|jg/m
    
    Hazard Ratio (96% Cl)
    MSA&DIFF
    Increment Change: 1.196 (1.177-1.407)
    Change 5-15 pg/m3:
    1.484(1.311-1.680)
    Change 10-20 pg/m3:
    1.283(1.186-1.387)
    HR(96%CI)
    Los Angeles
    Parsimonious ecologic covariates:
    1.263(10.22-1.563)
    HR(96%CI)
    Third follow-up, 7 Ecologic Variables
    1979-1983:1.184(1.146-1.222)
    1999-2000:1.242(1.191-1.295)
    HR(96%CI)
    Nationwide analysis, 1999-2000
    Standard Cox: 1.15 (1.11-1.20)
    Random Effects Cox: 1.24(1.19-1.29)
    Increment: 1.5|jg/m3
    HR(96%CI)
    28 County, 3 yr model
    All 7 ecologic covariates:
    1.072(0.980-1.172)	
    Reference: Krewski et al. (2009,
    1911931
    Period of Study: 1979-2000
    
    Location: 48 contiguous states U.S.
    Outcome: Death from lung cancer
    
    Study Design: Cohort
    
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
    
    Statistical Analysis: Cox proportional-
    hazards model
    
    Statistical Package: NR
    
    Age Groups: Adults of at least 30 yr
    Pollutant: PM25
    
    Averaging Time: NR
    
    Mean Unit:
    
    1979-1983: 21.20 pg/m3
    
    1999-2000:14.02 pg/m3
    
    Range (Min, Max):
    
    1979-1983:10.77-30.01
    
    1999-2000:5.80-22.20
    
    Copollutant:
    
    S042", S02, PM15, TSP, 03, N02, CO
    Increment: 10|jg/m
    
    Hazard Ratio (96% Cl)
    MSA&DIFF
    Increment Change: 1.142 (1.057-1.234)
    Change 5-15 pg/m3:
    1.236(1.114-1.372)
    Change 10-20 pg/m3:
    1.143(1.071-1.221)
    HR(96%CI)
    Los Angeles
    Parsimonious ecologic covariates:
    1.311 (0.897-1.915)
    HR(96%CI)
    16-yr time window
    GroupA: 1.08 (0.87-1.35)
    Group 6:1.07(1.02-1.13)
    HR(96%CI)
    Third follow-up, 7 Ecologic Variables
                                                                                                             1979-1983:1.092
                                                                                                                             1.033-1.154
                                                                                                                             1.057-1.225
                                                                                                             1999-2000:1.138
                                                                                                             HR(96%CI)
                                                                                                             Nationwide analysis, 1999-2000
                                                                                                             Standard Cox: 1.11 (1.04-1.18)
                                                                                                             Random Effects Cox: 1.14(1.06-1.23)
                                                                                                             Increment: 1.5|jg/m3
                                                                                                             HR(96%CI)
                                                                                                             28 County, 3-yr model
                                                                                                             All 7 ecologic covariates:
                                                                                                             0.985(0.832-1.166)	
    Reference: Krewski et al. (2009,
    1911931
    Period of Study: 1979-2000
    
    Location: 48 contiguous states U.S.
    Outcome: Death from diabetes
    
    Study Design: Cohort
    
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
    
    Statistical Analysis: Cox proportional-
    hazards model
    
    Statistical Package: NR
    
    Age Groups: Adults of at least 30 yr
    Pollutant: PM25
    
    Averaging Time: NR
    Mean Unit:
    1979-1983: 21.20 pg/m3
    1999-2000:14.02 pg/m3
    
    Range (Min, Max):
    1979-1983:10.77-30.01
    1999-2000:5.80-22.20
    
    Copollutant:
    S042", S02, PM15, TSP, 03, N02, CO
    Increment: 1.5|jg/m
    
    HR(96%CI)
    
    28 County, 3 yr model
    
    All 7 ecologic covariates:
    
    1.083(0.723-1.621)
    December 2009
                                   E-509
    

    -------
    Study
    Reference: Krewski et al. (2009,
    1911931
    
    Period of Study: 1979-2000
    Location: 48 contiguous states U.S.
    
    
    
    
    
    Reference: Krewski et al. (2009,
    1911931
    
    Period of Study: 1979-2000
    Location: 48 contiguous states U.S.
    
    
    
    
    
    Reference: Krewski et al. (2009,
    1911931
    
    Period of Study: 1979-2000
    Location: 48 contiguous states U.S.
    
    
    
    
    
    
    Reference: Krewski et al. (2009,
    1911931
    
    Period of Study: 1979-2000
    Location: 48 contiguous states U.S.
    
    
    
    
    
    
    Reference: McDonnell et al. (2000,
    0103191
    
    Period of Study: 1973-1977
    Location: California
    Design & Methods
    Outcome: Death from endocrine
    disease
    
    Study Design: Cohort
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
    
    Statistical Analysis: Cox proportional-
    hazards model
    Statistical Package: NR
    Age Groups: Adults of at least 30 yr
    Outcome: Death from digestive cancer
    
    Study Design: Cohort
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
    
    Statistical Analysis: Cox proportional-
    hazards model
    Statistical Package: NR
    Age Groups: Adults of at least 30 yr
    Outcome: Death cancers other than
    lung and digestive
    
    Study Design: Cohort
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
    
    Statistical Analysis: Cox proportional-
    hazards model
    Statistical Package: NR
    Age Groups: Adults of at least 30 yr
    Outcome: Deaths from causes other
    than CPD, IHD and lung cancer
    
    Study Design: Cohort
    Covariates: Demographic,
    socioeconomic and ecologic
    characteristics
    
    Statistical Analysis: Cox proportional-
    hazards model
    
    Statistical Package: NR
    Age Groups: Adults of at least 30 yr
    Outcome: Mortality
    
    Study Design: Cohort (AHSMOG
    airport cohort)
    Statistical Analyses: Cox regression
    models
    Concentrations1
    Pollutant: PM25
    
    Averaging Time: NR
    Mean Unit:
    1979-1983: 21.20 pg/m3
    1999-2000:1 4.02 pg/m3
    Range (Min, Max):
    1979-1983: 10.77-30.01
    1999-2000:5.80-22.20
    Copollutant:
    S042", S02, PM15, TSP, 03, N02, CO
    Pollutant: PM25
    
    Averaging Time: NR
    Mean Unit:
    1979-1983: 21.20 pg/m3
    1999-2000:1 4.02 pg/m3
    
    Range (Min, Max):
    1979-1983: 10.77-30.01
    1999-2000:5.80-22.20
    Copollutant:
    S042", S02, PM15, TSP, 03, N02, CO
    Pollutant: PM25
    
    Averaging Time: NR
    Mean Unit:
    1979-1983: 21.20 pg/m3
    1999-2000:1 4.02 pg/m3
    
    Range (Min, Max):
    1979-1983: 10.77-30.01
    1999-2000:5.80-22.20
    Copollutant:
    S042", S02, PM15, TSP, 03, N02, CO
    Pollutant: PM25
    
    Averaging Time: NR
    Mean Unit:
    1979-1983: 21.20 pg/m3
    1999-2000:1 4.02 pg/m3
    Range (Min, Max):
    1979-1983: 10.77-30.01
    1999-2000:5.80-22.20
    
    Copollutant:
    S042", S02, PM,5, TSP, 03, N02, CO
    Pollutant: PM25
    
    Averaging Time: Monthly avg
    Mean (SD): 31. 9 (10.7)
    IQR: 24.3
    Effect Estimates (95% Cl)
    Increment: 1.5|jg/m3
    
    HR(96%CI)
    28 County, 3-yr model
    All 7 ecologic covariates:
    1.143(0.835-1.564)
    
    
    
    
    
    Increment: 10|jg/m3
    
    HR(96%CI)
    Los Angeles
    Parsimonious ecologic covariates:
    1.199(0.817-1.758)
    
    
    
    
    Increment: 10|jg/m3
    
    HR(96%CI)
    
    Los Angeles
    Parsimonious ecologic covariates:
    1.012 (0.788-1.299)
    
    
    
    
    
    Increment: 10|jg/m3
    
    Hazard Ratio (96% Cl)
    MSA&DIFF
    Increment Change: 1.010(0.968-1.055)
    Change 5-1 5 pg/m3:
    1.026(0.970-1.085)
    Change 1 0-20 pg/m3:
    1.016(0.981-1.053)
    
    HR(96%CI)
    Third follow-up, 7 Ecologic Variables
    1979-1983:0.983(0.960-1.007)
    1999-2000: 0.953 (0.923-0.984)
    Increment: IQR
    
    All Cause: 1.22 (0.95-1. 58)
    Resp: 1.64 (0.93-2.90)
    Lung Cancer: 2.23 (0.56-8.94)
                                     Age Groups: Males, 27 yr+
       Copollutants (correlation):
       03: 0.68
       S02:0.18
       N02: -0.08;
       S04: 0.33
    December 2009
    E-510
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Miller et al. (2007, 0901301
    
    Period of Study: 1994-1998
    
    Location: 36 U.S. Metropolitan Areas
    Outcome: CVD Mortality
    
    Study Design: Prospective Cohort
    (WHI)
    
    Statistical Analyses: Cox proportional
    hazards regression
    
    Age Groups: Postmenopausal women
    ages 50-79
    Pollutant: PM25
    
    Averaging Time: Annual avg (2000)
    
    Mean (SD): 13.4
    
    IQR: 11.6, 18.3
    
    Range: 3.4, 28.3
    Increment: 10|jg/m
    
    CVD Death: 1.76 (1.25, 2.47)
    
    CHD Death: 2.21 (1.17, 4.16)
    
    CV Death: 1.83 (1.11, 3.00)
    Reference: Naess et al. (2007,
    0907361
    Period of Study: 1992-1998
    
    Location: Oslo, Norway
    Outcome: Mortality: Nonaccidental
    (<800)
    
    Lung cancer(162)
    
    COPD (490-496)
    
    Cardiovascular (390-459)
    
    Study Design: Prospective Cohort
    
    Statistical Analyses: Cox proportional
    hazards regression model
    
    Age Groups: 51-70, 71-90
    Pollutant: PM25
    
    Averaging Time: 4-yr avg
    
    Mean(SD):PM25:15
    
    Range (Min, Max): PM25: (7, 22)
    
    Copollutant (correlation):
    
    N02:r = 0.95
    Relative Risk (Cl min, Cl max)
    
    RR for deaths from all causes
    Men (ages 51-70) PM25 exposure
    (in pg/m3)
    6.56-11.45:1.00
    11.46-14.25:0.96(0.89, 1.04)
    14.26-18.43:1.12 1.03, 1.22
    18.44-22.34:1.48 1.36, 1.60
    Men (ages 71-90) PM25 exposure
    (in fjg/m )
    6.56-11.45:1.00
    11.46-14.25:0.99(0.93, 1.06)
    14.26-18.43:1.10 1.03, 1.17
    18.44-22.34:1.19 1.12,1.27
    Wfomen (ages 51-70) PM25 exposure
    (in fjg/m )
    6.56-11.45:1.00
    11.46-14.25:0.96(0.87, 1.07)
    14.26-18.43:1.08 0.98, 1.20
    18.44-22.34:1.44 1.30, 1.59
    Wfomen (ages 71 -90) PM25 exposure
    (in fjg/m )
    6.56-11.45:1.00
    11.46-14.25:1.03(0.97, 1.09)
    14.26-18.43:1.07(1.01, 1.12)
    18.44-22.34:1.11(1.05,1.16)
    
    Increment: 10 pg/m3
    RR for death from CVD and lung cancer
    Men (ages 51-70)
    CVD-PM25:1.11 (1.06,  1.16)
    COPD-PM25:1.32 (1.17,  1.49)
    Lung Cancer-PM25:1.07  (0.98,1.17)
    V\fomen(ages51-70)
    CVD:  PM25:1.16 (1.09,  1.24)
    COPD: PM25:1.18 (1.03,  1.34)
    Lung Cancer: PM25:1.23 (1.10,1.37)
    Men (ages 71-90)
    CVD:  PM25:1.06 (1.03,  1.09)
    COPD: PM,0:1.13 (1.04, 1.24)
    PM25:1.14 (1.04,  1.24)
    Lung Cancer: PM25:1.08 (0.98,1.19)
    V\fomen(ages71-90)
    CVD:  PM25:1.02 (1.00,  1.05)
    COPD: PM25:1.09 (1.00,  1.18)
    Lung Cancer: PM25:1.16 (1.03,1.31)
    Reference: Naess et al. (2007,
    0907361
    Period of Study: 1992-1998
    
    Location: Oslo, Norway
    Outcome: Mortality: Lung cancer (162)
    
    COPD (490-496)
    
    Cardiovascular (390-459)
    
    Psychiatric causes (290, 292-302,  304,
    306-319)
    
    Stomach cancer (151)
    
    Violence (800-999)
    
    Study Design: Multilevel cohort
    
    Statistical Analyses: WinBUGS
    
    Age Groups: 50-74
    Pollutant: PM25
    
    Averaging Time: (Mo-yr) avg
    
    Range Mean (SD): 14.2 (3.6)
    
    IQ Range (1st, 4th): (6.6, 22.3)
    
    Copollutant (correlation):
    
    PM10:r =  0.95|
    
    N02:r = 0.87
    Relative Risk (Cl min, Cl max)
    
    RR on All-cause mortality of PMz; in
    Men Age 60-74
    Primary Education:
    PM25:1.06 (1.00,1.11)
    Individual: 1.34 (1.24,1.43)
    Neighborhood: 1.22 (1.16,1.28)
    Manual Class: PM25:1.06 (1.01,1.12)
    Individual: 1.28 (1.20,1.37)
    Neighborhood: 1.20 (1.14,1.26)
    Income below median:
    PM25:1.05 (1.00, 1.12)
    Individual: 1.44 (1.35,1.53)
    Neighborhood: 1.16 (1.11,1.21)
    Not owner occupied:
    PM25:1.06 (1.00, 1.13)
    Individual: 1.24 (1.12,1.36)
    Neighborhood: 1.11 (1.05,1.17)
    Lives in flat dwelling:	
    December 2009
                                    E-511
    

    -------
                  Study                       Design & Methods                  Concentrations1              Effect Estimates (95% Cl)
    
                                                                                                                  PM25:1.04(0.98, 1.11)
                                                                                                                  Individual:  1.19 (1.09,1.31)
                                                                                                                  Neighborhood:  1.10 (1.04,1.17)
                                                                                                                  More than one person per room in
                                                                                                                  dwelling: PM25:1.10 (1.02,1.18)
                                                                                                                  Individual:  1.05 (0.98,1.13)
                                                                                                                  Neighborhood:  1.01 (0.96,1.05)
    
                                                                                                                  RR on All-cause mortality of PWh.s in
                                                                                                                  Women Age 60-74
                                                                                                                  Primary Education Only:
                                                                                                                  PM25:1.05 (1.00,1.11)
                                                                                                                  Individual:  1.32 (1.23,1.42)
                                                                                                                  Neighborhood:  1.18 (1.12,1.24)
                                                                                                                  Manual Class: PM25:1.07 (1.01,1.13)
                                                                                                                  Individual:  1.27 (1.18,1.36)
                                                                                                                  Neighborhood:  1.18 (1.12,1.24)
                                                                                                                  Income below median:
                                                                                                                  PM25:1.05 (1.01,1.10)
                                                                                                                  Individual:  1.52 (1.41,1.63)
                                                                                                                  Neighborhood:  1.13 (1.09,1.18)
                                                                                                                  Not owner occupied:
                                                                                                                  M25:1.07 (1.01,1.14)
                                                                                                                  Individual:  1.24 (1.12,1.38)
                                                                                                                  Neighborhood:  1.08 (1.02,1.14)
                                                                                                                  Lives in a flat dwelling:
                                                                                                                  PM25:1.05 (0.99, 1.11)
                                                                                                                  Individual:  1.21  (1.09,1.34)
                                                                                                                  Neighborhood:  1.09 (1.02,1.15)
                                                                                                                  More than one person per room in
                                                                                                                  dwelling: PM25:1.11 (1.04,1.19)
                                                                                                                  Individual:  1.07 (0.99,1.14)
                                                                                                                  Neighborhood:  1.01 (0.96,1.05)
    
                                                                                                                  RRfor Interquartile Increase (Ml) in
                                                                                                                  PM2 5 for different causes of death
                                                                                                                  CVD:
                                                                                                                  Age and sex adjusted: 1.11 (1.07,1.15)
                                                                                                                  Primary education only:
                                                                                                                  M1+Individual: 1.07 (1.04,1.11)
                                                                                                                  M1+Neighborhood: 1.03 (1.00,1.07)
                                                                                                                  Manual Class: M1+ Individual: 1.08
                                                                                                                  (1.04,1.11)
                                                                                                                  M1+Neighborhood: 1.06 (1.02,1.10)
                                                                                                                  Income below Median: M1+ Individual:
                                                                                                                  1.07(1.03,1.11)
                                                                                                                  M1+Neighborhood: 1.02 (0.98,1.05)
                                                                                                                  Not owner occupied:
                                                                                                                  M1+Individual: 1.05 (1.01,1.09)
                                                                                                                  M1+ Neighborhood: 1.03(0.99,1.07):
                                                                                                                  Living in a Flat dwelling
                                                                                                                  M1+Individual: 1.04 (1.00,1.08)
                                                                                                                  M1+Neighborhood: 1.01 (0.97,1.05)
                                                                                                                  Crowded household:
                                                                                                                  M1+Individual: 1.10 (1.05,1.14)
                                                                                                                  M1+Neighborhood: 1.10 (1.06,1.15)
                                                                                                                  Pulmonary Cancer: Age and sex
                                                                                                                  adjusted: 1.12 (1.05,1.19)
                                                                                                                  Primary education only:
                                                                                                                  M1+Individual: 1.09 (1.01,1.17)
                                                                                                                  M1+Neighborhood: 1.05 (0.98,1.13)
                                                                                                                  Manual Class:
                                                                                                                  M1+Individual: 1.09 (1.01,1.17)
                                                                                                                  M1+Neighborhood: 1.10 (1.06,1.13)
                                                                                                                  Income below Median:
                                                                                                                  M1+Individual: 1.09 (1.01,1.17)
                                                                                                                  M1+Neighborhood: 1.02 (0.95,1.10)
                                                                                                                  Not owner occupied:
                                                                                                                  M1+Individual: 1.07 (1.00,1.15)
                                                                                                                  M1+Neighborhood: 1.04 (0.97,1.12)
                                                                                                                  Living in a Flat dwelling:
                                                                                                                  M1+Individual: 1.03 (0.96,1.11)
                                                                                                                  M1+Neighborhood: 1.00 (0.92,1.08)
                                                                                                                  Crowded household:
                                                                                                                  M1+Individual: 1.10 (1.03,1.14)
                                                                                                                  M1+Neighborhood:1.11 (1.04,1.20)
                                                                                                                  COPD: Age and sex adjusted:
                 	1.17(1.09,1.25)	
    December 2009                                                    E-512
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
                                                                                                                 Primary education only:
                                                                                                                 M1+Individual: 1.13 (1.05,1.22)
                                                                                                                 M1+Neighborhood: 1.09 (1.01,1.19)
                                                                                                                 Manual Class:
                                                                                                                 M1+Individual: 1.14 (1.05,1.23)
                                                                                                                 M1+Neighborhood: 1.12 (1.04,1.22)
                                                                                                                 Income below Median:
                                                                                                                 M1+Individual: 1.13 (1.04,1.22)
                                                                                                                 M1+Neighborhood: 1.06 (0.97,1.15)
                                                                                                                 Not owner occupied: M1+ Individual:
                                                                                                                 1.10(1.02,1.19)
                                                                                                                 M1+Neighborhood: 1.07 (0.99,1.16)
                                                                                                                 Living in a Flat dwelling:
                                                                                                                 M1+Individual: 1.08 (1.00,1.18)
                                                                                                                 M1+Neighborhood: 1.03 (0.95,1.13)
                                                                                                                 Crowded  household:
                                                                                                                 M1+Individual: 1.16 (1.07,1.26)
                                                                                                                 M1+Neighborhood: 1.16 (1.07,1.26)
                                                                                                                 Estimates for psychiatric diseases,
                                                                                                                 genetic cancer and violent death
    Reference: Nerriere et al. (2005,
    0886301
    Period of Study:
    Grenoble (2001)
    Paris (2002)
    Rouen (2002-2003)
    Strasbourg (2003)
    
    Location: Four French Cities-
    Grenoble, Rouen, Paris, and
    Strasbourg
    Outcome: Mortality: Lung Cancer (162)  Pollutant: PM25
    
    Study Design: Time-series            Averaging Time: 48-h avg
    Statistical Analyses: GIS
    
    Age Groups: 30-71 yr old nonsmoking
    adults
    Mean Range: 17 to 49 pg/m3
    Increment: 10|jg/m
    
    % Increase (Lower Cl, Upper Cl)
    
    % increase in lung cancer deaths
    attributable to PM2 5 exposure
    France: 8(1,16)
    Grenoble:  10 (3,19)
    Rouen: 10 (2,19)
    Strasbourg: 24  (4, 40)
    Reference: Ozkaynak and Thurston
    (1987, 0729601
    
    Period of Study: 1980
    
    Location: U.S.
    Outcome: Total Mortality
    
    Study Design: Cross-sectional
    
    Statistical Analyses: Multiple
    regression analysis
    Pollutant: Sulfate
    
    Averaging Time: Annual avg
    
    Mean Range: Sulfate: 11.1 (3.5)
    Range of estimated total mortality
    effects of air pollutions:
    
    Sulfate: 4-9%
    
    "Sulfate concentration was consistently
    found to be a significant predictor of
    mortality in the models considered. Fine
    particle mass coefficients were also
    often found to be statistically significant
    in the mortality regressions."
    Reference: Pope et al. (2004, 0558801
    
    Period of Study: 1982-2000
    
    Location: Metropolitan areas in all 50
    states in the U.S.
    Outcome: Mortality: Cardiovascular
    Diseases (390-459)
    
    Diabetes (250)
    
    Respiratory Disease (460-519)
    
    Study Design: Prospective Cohort
    
    Statistical Analyses: Cox proportional
    hazards regression
    
    Age Groups: >30
    Pollutant: PM25
    
    Averaging Time: Annual avg
    
    Mean (SD): 17.1 (3.7)
    
    Range (Min, Max): NR
    Increment: 10|jg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    All cardiovascular disease plus
    diabetes: PM25:1.12 (1.08,1.15)
    FormerSmoker: 1.26 (1.23,1.28)
    Current Smoker: 1.94 (1.90,1.99)
    Ischemic Heart Disease: PM25:1.18
    (1.14,1.23)
    Former Smoker: 1.33 (1.29,1.37)
    Current Smoker: 2.03 (1.96, 2.10)
    Diabetes: PM25: 0.99 (0.86,1.14)
    Former Smoker: 1.05 (0.94,1.16)
    Current Smoker: 1.35 (1.20,1.53)
    All other Cardiovascular Diseases:
    PM25: 0.84 (0.71, 0.99)
    Former Smoker: 1.22 (1.09,1.38)
    Current Smoker: 1.78 (1.56, 2.04)
    Diseases of the respiratory system:
    PM25: 0.92 (0.86, 0.98)
    Former Smoker: 2.16 (2.04, 2.28)
    Current Smoker: 3.88 (3.66, 4.11)
    COPD: PM25: 0.84 (0.77,  0.93)
    Former Smoker: 4.93 (4.48, 5.42)
    Current Smoker: 9.85 (8.95,10.84)
    All other respiratory diseases: PM25:
    0.86(0.73, 1.02)
    Former Smoker: 1.54 (1.36,1.74)
    Current Smoker: 1.83 (1.57, 2.12)
    December 2009
                                     E-513
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Reference: Pope et al. (2007, 0912561
    
    Period of Study: 1960-1975
    
    Location: New Mexico, Arizona, Utah,
    and Nevada
    Outcome (ICD7&8):
    
    Mortality: Cardiovascular (ICD 7: 400-
    468, 331, 332 ICD 8: 390-458)
    
    Respiratory (ICD 7: 470-527 ICD 8:
    460-519)
    
    Influenza/ pneumonia (ICD 7: 480-483,
    490-493, ICD 8: 470-474, 480-486)
    
    Study Design: Retrospective Cohort
    
    Statistical Analyses: Poisson
    regression model
    
    GAM
    
    SAS
    
    Age Groups: All smelter workers >18
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Mean (SD): NR
    
    Range (Min, Max): NR
    The study does not present quantitative
    results
    
    Results are presented in figures. The
    References found that the strike-related
    estimated percent decrease in mortality
    was 2.5% (1.1-4.0),
    Reference: Pope et al. (2009,1901071
    
    Period of Study: 1978-1982,
    1997-2001
    
    Location: 211 U.S. counties and 51
    metropolitan areas
    Outcome: Increased life expectancy
    
    Study Design: Cross-sectional
    
    Statistical Analysis: Cross-sectional
    regression
    
    Age Groups: Adults >45 yr
    Pollutant: PM25
    
    Averaging Time: Daily, quarterly and
    annual
    
    Mean (SD) Unit:
    
    1979-1983: 20.61+ 4.36 pg/m3
    
    1999-2000:14.10 + 2.86 pg/m3
    
    Range (Min, Max): NR
    
    Copollutant (correlation): NR
    Increment: 10|jg/m
    
    Regression Coefficient + SD
    211 County Units
    Intercept: 1.75 ±0.27
    Reduction in PM25: 0.61 ±0.20
    Change in Income: 0.13 ±0.01
    Change in Population: 0.06 ± 0.02
    Change in Black Population:
    -2.70 ±0.64
    Change in Lung Cancer Mortality Rate:
    -0.06 ±0.02
    Change in COPD  Mortality Rate:
    -0.08 ±0.02
    R: 0.53
    51 Metropolitan Areas
    Intercept: 2.09 ±0.36
    Reduction in PM25: 0.95 ± 0.23
    Change in Income: 0.11 ±0.02
    Change in Population: 0.05 ± 0.02
    Change in Black Population:
    -5.98 ±1.99
    Change in Lung Cancer Mortality Rate:
    0.02 ± 0.03
    Change in COPD  Mortality Rate:
    -0.19 ±0.05
    R: 0.74
    December 2009
                                    E-514
    

    -------
                   Study
            Design & Methods
                                  Concentrations1
                                             Effect Estimates (95% Cl)
    Reference: Rainham et al. (2005,
    0886761
    
    Period of Study: 1981-1999
    
    Location: Toronto, Canada
    Outcome: Total deaths (ICD9 <800),     Pollutant: PM2
    cardiorespiratory
    cardiorespiratory
    390-459), non-
    ICD9-NR)
    Study Design: Time-series
    
    Statistical Analyses: Generalized
    linear models were used
    
    Season: Winter (Dec-Feb)
    
    Summer (Jun-Aug)
    
    Statistical Package: S-Plus 6.1
    Averaging Time: NR
    Mean (SD):
    All yr: 17.0 (8.7) pg/m3
    Winters: 17.2 (6.8)
    Summers: 18.8(10.2)
    AvgWnter values: Dry Moderate: 17.0
    (1.0)
    Dry Polar: 17.5 (0.5)
    Dry Tropical: No Comparison
    Moist Moderate: 17.1  (0.8)
    Moist Polar: 17.5 (0.6)
    Moist Tropical: 16.5(3.6)
    Transition: 16.7 (1.0)
    Avg summer values: Dry Moderate:
    18.4(0.9)
    Dry Polar: 19.0 (1.2)
    Dry Tropical: 18.5(2.4)
    Moist Moderate: 19.2 (1.2)
    Moist Polar: 17.5 (2.0)
    Moist Tropical: 19.8 (1.1)
    Transition: 17.6 (1.5)
    Mortality risk for winter season and
    within winter synoptic weather
    categories
    
    RR Estimate [Lower Cl, Upper Cl]:
    Winter: Total: 0.998(0.997,1.000]
    Cardioresp: 0.998(0.996,1.000]
    Other: 0.998 [0.996, 1.000]
    Dry Moderate:
    Total: 1.001(0.996, 1.007]
    Cardioresp: 1.005(0.998,1.011]
    Other: 1.002 [0.998,1.005]
    Dry Polar: Total: 0.998(0.995,1.001]
    Cardioresp: 0.995(0.991, 0.999]
    Other: 1.002 [0.998,1.005]
    Dry Tropical: NA
    Moist Moderate:
    Total: 0.998(0.993, 1.002]
    Cardioresp: 1.003(0.995,1.010]
    Other: 0.997 [0.991,1.004]
    Moist Polar: Total: 1.001(0.998,1.005]
    Cardioresp: 1.002(0.997,1.007]
    Other: 1.003 [0.999,1.007]
    Moist Tropical:
    Total: 1.007(0.965, 1.203]
    Cardioresp: 1.123(1.031,1.224]
    Other: 1.248 [1.123,1.387]
    Transition Total: 1.003(0.996,1.009]
    Cardioresp: 0.996(0.987,1.004]
    Other: 0.997 [0.990, 1.004]
    
    Mortality risk for summer season and
    within summer synoptic weather
    categories
    RR Estimate [Lower Cl, Upper Cl]:
    Summer: Total: 1.000(1.000,1.001]
    Cardioresp: 1.001 [1.000,1.002]
    Other: 1.001 [1.000,1.002]
    Dry Moderate:
    Total: 1.001(0.999, 1.002]
    Cardioresp: 1.002(0.999,1.004]
    Other: 0.999(0.997, 1.002]
    Dry Polar: Total: 1.002(0.999,1.005]
    Cardioresp: 0.996(0.991,1.000]
    Other: 1.003 0.999,1.007]
    Dry Tropical: Total: 1.016(1.006,1.027]
    Cardioresp: 1.017(1.005,1.030]
    Other: 1.017 [1.003,1.031]
    Moist Moderate:
    Total: 1.002(1.000, 1.004]
    Cardioresp: 1.003(0.999,1.006]
    Other: 1.004 [1.001,1.006]
    Moist Polar:
    Total: 1.005(0.998, 1.011]
    Cardioresp: 1.008(0.997,1.018]
    Other: 1.003 [0.995,1.011]
    Moist Tropical:
    Total: 0.999(0.997, 1.001]
    Cardioresp: 0.996(0.993,1.000]
    Other: 0.998 [0.995,1.001]
    Transition: Total: 1.005(0.996,1.014]
    Cardioresp: 1.007(0.994,1.020]
    Other: 1.002 [0.996,1.008]	
    Reference: Roman et al. (2008,
    1569211
    Period of Study: 2006
    
    Location: U.S.
    Outcome: Mortality
    
    Study Design: Expert Judgment Study
    
    Statistical Analyses: Standard best
    practices for expert elicitation
                         Pollutant: PM25
    
                         Averaging Time: Annual avg
    
                         Mean (SD): 4-30
                                         Quantitative results are not presented in
                                         the text, but can be found graphically in
                                         Fig 3.
    
                                         "Most of the experts' central estimates
                                         fall at or above the 2002 ACS median
                                         (0.6% per pg/m3) and below the original
                                         Six Cities median  (1.2% per pg/m )."
    December 2009
                                     E-515
    

    -------
                  Study
                                               Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Schwartz, et al. (2008,
    156921
                                        Outcome: Mortality
    Pollutant: PM2
    PM Increment: 10 pg/m
    
    Period of Study: 1979-1988
    Location: Six U.S. metropolitan areas:
    Boston, Massachusetts
    Knoxville, Tennessee
    
    St. Louis, Missouri
    Steubenville, Ohio
    Madison, Wisconsin
    
    and Topeka, Kansas
    Study Design: Poisson regression with
    GAM
    Statistical Analyses: Weighted linear
    regression
    Season: all
    
    Dose-response Investigated? No
    Statistical Package: S-plus
    
    
    
    Averaging Time: Daily
    Mean (SD):
    Boston-16.5
    Knoxville-21.1
    St. Louis-19.2
    Steubenville-30.5
    Madison-11.3
    Topeka-12.2
    SD not reported
    Range (Min, Max): (0,35)
    
    Monitoring Stations: 6
    
    The difference between mean PM25
    concentrations of 10 pg/m3 and 20
    pg/m3 is associated with about a 1.5%
    increase in deaths.
    
    
    
    
    
    
    
    Reference: (Schwartz et al, 2008,
    1569631
    
    Period of Study: 1979-1998
    
    Location: Watertown, MA
    
    Kingston and Harriman, TN
    
    St Louis, MO
    
    Steubenville, OH
    
    Portage, Wyocena
    
    Pardeeville Wl
    
    Topeka, KS
                                        Outcome: Mortality: Nonaccidental
                                        (<800)
    
                                        Study Design: Cross-sectional
    
                                        Statistical Analyses: Cox proportional
                                        hazards regression
    
                                        penalized splines
    
                                        Bayesian Model Averaging
    
                                        Age Groups: >18
    Pollutant: PM25
    
    Averaging Time: Annual avg
    
    Mean (SD): 17.5 (6.8)
    
    Range (Min, Max): (8, 40)
    Increment: 10 pg/m
    
    Relative Risk (Lower Cl, Upper Cl)
    Estimated from Fig 4:
    All Cause Mortality - Year before Death
    0:1.10(1.00,1.21)
    1:1.03(0.98, 1.08)
    2:1.01 (1.00, 1.02)
    3:1.00(0.99,1.01)
    4:1.00(0.99,1.01)
    5:  1.00
    Lung Cancer Mortality - Year Before
    Death
    Estimated from Fig 6
    0:1.18(1.00,1.48)
    1:1.12(0.98, 1.33)
    2:1.08 0.92, 1.22)
    3:1.02(1.01,1.03)
    4:1.01(1.00,1.02)
    5:  1.01
    RR per 10 pg/m3 increase of PM25
    exposure
    Level Of Increase
    Estimated from Fig 3
    10 pg/m3:1.15
    20 pg/m3:1.29
    30 pg/m3:1.46
    40 pg/m3:1.64	
    Reference: Tainio et al. (2005, 0874441  Outcome (ICD10): Mortality:            Pollutant: PM25
                                        Cardiopulmonary (111-170 and J15-J47)
                                                                            Averaging Time: 24-h avg
    Period of Study: 1997-Present
    
    Location: Helsinki, Finland
                                        Study Design: Time-series simulation
    
                                        Statistical Analyses: Monte Carlo
                                        Simulation
    
                                        Age Groups: All ages
                                                                           Mean (SD): 10.7
    
                                                                           Range (Min, Max): NR
                                        Estimated Deaths Per Year (Min Cl,
                                        Max Cl) Associated with Primary
                                        PM2.s
    
                                        Emissions from buses in Helsinki in
                                        2020 for different bus strategies
                                        Cardiopulmonary Mortality
                                        Current Fleet: 15.9 (0,46.6)
                                        Modern Diesel: 7.9 (0, 23.0)
                                        Diesel with particle trap: 3.9 (0,12)
                                        Natural gas bus: 2.3 (0, 6.8)
                                        Lung Cancer Mortality
                                        Current Fleet: 2.2 (0,6.1)
                                        Modern Diesel: 1.1  (0,3.0)
                                        Diesel with particle trap: 0.6 (0,1.6)
                                        Natural gas bus: 0.3 (0, 0.9)
                                        Total Mortality
                                        Current Fleet: 18.1  (0,55.0)
                                        Modern Diesel: 9.0 (0, 27.0)
                                        Diesel with particle trap: 4.4 (0,14.1)
                                        Natural Gas Bus: 2.6 (0, 8.0)	
    December 2009
                                                                        E-516
    

    -------
                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Villeneuve et al. (2002,
    0425761
    
    Period of Study: 1974-1991
    
    Location: Six U.S. Cities: Steubenville,
    OH, St. Louis, MO, Portage, Wl,
    Topeka, KS, Watertown, MA,  Kingston/
    Harriman, TN
    Outcome (ICD10): Mortality:
    Nonaccidental (<800)
    
    Study Design: Prospective Cohort
    
    Statistical Analyses: Poisson,
    EPICURE
    
    Age Groups: All ages
    
    <60
    
    >60
    Pollutant: PM25
    
    Averaging Time: 24-h avg
    
    Mean (SD): Portage: 10.9 (7.2)
    
    Topeka: 12.1 (7.1)
    
    Harriman: 20.7 (9.4)
    
    Watertown: 14.9 (8.4)
    
    St. Louis: 18.7 (10.6)
    
    Steubenville: 28.6 (21.0)
    
    Overall: 18.6
    
    Range (Min, Max): NR
    Increment: 18.6 pg/m
    
    Relative Risk (Min Cl, Max Cl)
    RR of all cause mortality for exposure of
    PM2 5 by age group
    Exposure to PM25  remained fixed over
    entire study period
    <60:1.89 (1.32, 2.69)
    >60:1.21 (1.02, 1.43)
    Total: 1.31 (1.12,1.52)
    Exposure to PM25  was defined
    according to 13 calendar periods* (no
    smoothing)
    <60:1.52 (1.15, 2.00)
    >60:1.11 (0.95, 1.29)
    Total: 1.19 (1.04,1.36)
    Exposure to PM25  was defined
    according to 13 calendar periods*
    (smoothed)
    <60:1.43 (1.10, 1.85)
    >60:1.09 (0.93, 1.26)
    Total: 1.16 (1.02,1.32)
    Time dependent estimate of PM2 5
    received during the previous 2 yr
    <60:1.42 (1.09, 1.82)
    >60:1.08 (0.94, 1.25)
    Total: 1.16 (1.02,1.31)
    Time dependent estimate of PM2 5
    received 3-5 yr before current yr
    <60:1.35 (1.08, 1.67
    >60:1.08 (0.95, 1.22
    Total: 1.14 (1.02,1.27)
    Time dependent estimate of PM2 5
    received >5 yr before current yr
    <60:1.34 (1.11, 1.59)
    >60:1.09 (0.99, 1.20)
    Total: 1.14 (1.05,1.23)
    * The calendar periods used were:
    1970-1978, 1979,  1980, 1981, 1982,
    1983, 1984, 1985,  1986, 1987, 1988,
    1989, and 1990+.
    RR of all cause mortality and PM25
    exposure by city
    Portage: 1.16 (0.96,1.39)
    Topeka: 1.06 (0.89,1.27)
    Harriman
    Men: 1.04 (0.79,1.36)
    Women: 0.96 (0.69,1.31)
    All: 1.13 (0.95, 1.35)
    Watertown
    Men: 1.20 (0.95,1.51)
    Women: 1.06 (0.78,1.43)
    All: 1.32 (1.11,1.51)
    St. Louis
    Men: 0.97 (0.76, 1.24)
    Women: 1.13 (0.86,1.49)
    Steubenville
    Men: 1.39 (1.11,1.74)
    Women: 1.22 (0.93,1.61)	
    Reference: Willis et al. (2003, 0899221
    
    Period of Study: 1982-1989
    
    Location: U.S. Metropolitan areas in all
    50 states
    Outcome: Mortality: All causes
    
    Lung Cancer (162)
    
    Cardiopulmonary (401-440, 460-519)
    
    Study Design: Prospective Cohort
    
    Statistical Analyses: Cox proportional
    hazards model
    
    Age Groups: All ages
    Pollutant: Sulfates
    
    Averaging Time: Annual avg
    
    Mean (SD): 10.6 pg/m3
    
    Range (Min, Max): 3.6, 23.5
    
    Copollutant: CO, N02, 03, S02
    All Cause, Metropolitan Scale: 1.25
    (1.13, 1.37)
    
    All Cause, County Scale: 1.50 (1.30,
    1.73)
    
    CPD,  Metropolitan Scale: 1.29 (1.15,
    1.46)
    
    CPD,  County Scale: 1.75 (1.48, 2.08)
    Reference: Zanobetti and Schwartz     Outcome: Mortality, all causes,
                                        Pollutant: PM25
                                        Increment: 10|jg/m
    Period of Study: 1999-2005
    Location: 112 U.S. Cities
    Study Design: Time-series
    Covariates: Region, season
    Averaging Time: 24 h
    Mean (SD)
    Birmingham AL- 16.5
    Phoenix AZ- 11. 4
    LittleRockAR-14.3
    Percent Increase (96% Cl) in
    mortality by increment of PM2 5,
    combined by season
    All Cause Mortality
    Overall: 0.98 (0.75-1. 22)
    December 2009
                                     E-517
    

    -------
    Study Design & Methods Concentrations1
    Statistical Analysis: Poisson Łres no CA - 19.4
    recession BakersfieldCA-217
    regresslon LosAngelesCA-19.9
    Age Groups1 All Anaheim CA- 16.3
    RubidouxCA-24.9
    Sacramento CA- 13.0
    EICajonCA-13.5
    Denver CO -10. 3
    Hartford CT-1 1.6
    New HavenCT -13. 7
    Wilmington DE- 15.1
    Davie FL - 8.4
    Miami FL- 9.4
    Jacksonville FL- 10.6
    PensacolaFL-12.4
    Tampa FL- 11. 9
    Orlando FL-1 0.3
    Palm beach FL- 7.9
    PinellasFL-10.4
    Atlanta GA- 17. 6
    Chicago IL- 15.9
    Gary IN -15.3
    Indianapolis IN -16.3
    Cedar Rapids IA- 11.0
    DesMoineslA-10.5
    Davenport IA- 12.3
    Louisville KY- 15.9
    Baton Rouge LA -13. 4
    AvondaleLA-12.3
    New Orleans LA -12.6
    Baltimore MD- 15.6
    Springfield MA -12.3
    Boston MA -12.4
    Worcester MA -11. 3
    Holland Ml -12.1
    Grand Rapids Ml -13.6
    Detroit Ml -16.2
    Minneapolis MN- 11.1
    Kansas MO -12.0
    St Louis MO -14.5
    Omaha NE- 10.4
    Elizabeth NJ - 14.7
    Albuquerque NM - 6.7
    New York NY -14.8
    Bath NY -9.6
    Durham NC- 14.3
    WnstonNC-14.7
    GreensboroughNC-14.2
    Charlotte NC- 15. 3
    Raleigh NC- 14.3
    MiddletownOH-16.4
    YoungstownOH-15.6
    Cleveland OH -16.4
    Columbus OH -16.2
    Cincinnati OH -17.1
    SteubenvilleOH-17.0
    Toledo OH -14.9
    Dayton OH -16.2
    Akron OH - 16.0
    Warren OH -15.3
    Oklahoma OK - 9.9
    TulsaOK-11.1
    Bend OR - 7.8
    MedfordOR-9.9
    KlamathOR-10.6
    Eugene OR - 8.0
    Portland OR - 8.8
    Gettysburg PA -13. 4
    Pittsburgh PA- 15.7
    State College PA -13.2
    Carlisle PA -15.1
    Harrisburg PA- 15.5
    Erie PA -13.1
    ScrantonPA- 11.8
    AllentownPA-14.2
    WlkesBarrePA-12.8
    Mercer PA -14.1
    EastonPA-14.0
    Effect Estimates (95% Cl)
    Wnter: 0.56 (0.17-0.94)
    Spring: 2.57 (1.96-3. 19)
    Summer: 0.25 (-0.1 3-0.63)
    Fall: 0.95 (0.56-1. 34)
    CVD
    Overall: 0.85 (0.46-1. 24)
    Wnter: 0.70 (0.04-1. 36)
    Spring: 2. 18 (1.22-3. 15)
    Summer: -0.03 (-0.75-0.69)
    Fall: 0.92 (0.17-1. 68)
    Ml
    Overall: 1.18 (0.48-1. 89)
    Wnter: 1.29 (-0.14-2.75)
    Spring: 2. 12 (0.53-3.74)
    Summer: -0.03 (-1.46-1. 42)
    Fall: 1.24 (0.12-2.36)
    Stroke
    Overall: 1.78 (0.96-2.62)
    Wnter: 1.93 (0.34-3.54)
    Spring: 2.04 (-0.02-4.13)
    Summer: 1.64 (0.05-3.26)
    Fall: 1.69 (0.06-3.35)
    Respiratory
    Overall: 1.68 (1.04-2.33)
    Wnter: 0.86 (-0.16-1.88)
    Spring: 4.62 (3.08-6. 18)
    Summer: 0.78 (-0.49-2.06)
    Fall: 1.45 (0.19-2.72)
    
    Percent Increase (96% Cl) in
    mortality by increment in PM25
    combined by region
    All Cause Mortality
    Humid Subtropical and Maritime:
    1.02(0.65-1.38)
    Warm Summer Continental:
    1.19(0.73-1.64)
    Hot Summer Continental:
    1.14(0.55-1.73)
    Dry: 1.1 8 (-0.70-3. 10)
    Dry, Continental: 1.26 (-0.21-2.76)
    Mediterranean: 0.50 (0.00-1.01)
    CVD
    Humid Subtropical and Maritime:
    0.78(0.05-1.51)
    Warm Summer Continental:
    1.43(0.67-2.19)
    Hot Summer Continental:
    0.43 (-0.53-1. 40)
    Dry: 3.11 (-0.02-6.33)
    Dry, Continental: 1.67 (-0.75-4.16)
    Mediterranean: 0.16 (-0.46-0.79)
    Ml
    Humid Subtropical and Maritime:
    0.97 (-0.29-2.26)
    Warm Summer Continental:
    1.50(0.05-2.97)
    Hot Summer Continental:
    0.64 (-0.96-2.28)
    Dry: 4.25 (-2.38-11. 33)
    Dry, Continental: 0.60 (-7.42-9.32)
    Mediterranean: 1.85 (-0.66-4.41)
    Stroke
    Humid Subtropical and Maritime:
    2.94(1.59-4.32)
    Warm Summer Continental:
    1.85(0.04-3.69)
    Hot Summer Continental:
    0.77 (-1.77-3.38)
    Dry: 1.82 (-6.98-11. 45)
    Dry, Continental: 2.49 (-2.32-7.53)
    Mediterranean: 0.95 (-0.66-2.59)
    Respiratory
    Humid Subtropical and Maritime:
    0.91 (-0.25-2.08)
    Warm Summer Continental:
    2.12(0.89-3.36)
    Hot Summer Continental:
    December 2009
    E-518
    

    -------
                 Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                         Philadelphia PA-14.5
                                                                         Washington PA-14.7
                                                                         Providence Rl-11.5
                                                                         Charleston SC-12.1
                                                                         Taylors SC-15.3
                                                                         Columbia SC-14.0
                                                                         SpartanburgSC-14.2
                                                                         Nashville TN -14.0
                                                                         KnoxvilleTN-16.0
                                                                         Memphis TN-13.5
                                                                         San Antonio TX - 9.4
                                                                         Dallas TX-12.9
                                                                         El Paso TX-9.2
                                                                         Houston TX-12.9
                                                                         Port Arthur TX-11.5
                                                                         Ft Worth TX-12.2
                                                                         Austin TX-10.4
                                                                         Salt Lake UT-11.5
                                                                         Provo UT - 9.5
                                                                         WDCVA-15.2
                                                                         AnnandaleVA-14.0
                                                                         Dumbarton VA-13.6
                                                                         Chesapeake VA-12.7
                                                                         Norfolk VA-12.7
                                                                         Richmond VA-14.3
                                                                         Seattle WA-10.1
                                                                         TacomaWA-11.2
                                                                         Spokane WA-9.1
                                                                         Dodge Wl -11.1
                                                                         Milwaukee Wl -13.2
                                                                         WaukeshaWI-13.2
                                                                         Range (Min, Max): NR
    
                                                                         Copollutant (correlation): NR
                                                                         3.36(1.95-4.79)
                                                                         Dry: 5.81 (-0.04-12.00)
                                                                         Dry, Continental:-0.31 (-5.89-5.61)
                                                                         Mediterranean: 1.06 (-0.36-2.50)
    Reference: Zeger et al. (2007,1571761  Outcome: Mortality
    
    Period of Study: 2000-2002
    
    Location: 250 largest U.S. counties
    Study Design: Retrospective Cohort
    (MCAPS)
    Pollutant: PM25
    
    Averaging Time: 3-yr avg
                                      Statistical Analyses: Log-linear
                                      regression models (GAM)
    
                                      Covariates: Age, gender, race, county-
                                      level SES, education and COPD SMR
    
                                      Age Groups: 65+
    
                                      65-74, 75-84, 85+
    Increment: 10|jg/m
    
    65+: 1.076 (1.044, 1.108)
    
    Eastern U.S.: 1.125 (1.091,1.159)
    
    Central U.S.: 1.196 (1.115,1.277)
    
    Western U.S.: 1.029 (0.994,1.064)
    
    65-74:1.156(1.117, 1.196)
    
    75-84:1.081 (1.042, 1.121)
    
    85+: 0.995 (0.956, 1.035)
    December 2009
                                   E-519
    

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                  Study
           Design & Methods
            Concentrations1
        Effect Estimates (95% Cl)
    Reference: Zeger et al. (2008,1919511  Outcome: Mortality
    Period of Study: 2000-2005
    
    Location: 4568 zip codes in urban
    areas
    Study Design: Retrospective Cohort
    
    Statistical Analysis: Log-linear
    regression model
    
    Age Groups: Ł65
    Pollutant: PM25
    
    Averaging Time: Annual
    
    Median (SD) Unit:
    
    Eastern: 14.0|jg/m3
    
    Central: 10.7 pg/m3
    
    Western:  13.1 pg/m3
    
    All: 13.2 pg/m3
    
    Range (IQR):
    
    Eastern: 12.3-15.3
    
    Central: 9.8-12.2
    
    Western:  10.4-18.5
    
    All: 11.1-14.9
    
    Copollutant (correlation): NR
    Increment: 10 pg/m
    
    Relative Risk (Min Cl, Max Cl) lag
    
    Risk estimate for increase in mortality
    per increase in PM25, all ages
    Eastern Region
    Age: 1.155(1.130-1.180)
    Age+ SES: 1.105 (1.084-1.125)
    Age + SES + COPD:
    1.068(1.049-1.087)
    Central Region
    Age: 1.178 (1.133-1.222)
    Age + SES: 1.089 (1.052-1.125)
    Age + SES + COPD:
    1.132(1.095-1.169)
    Western Region
    Age: 1.003 (0.981-1.025)
    Age + SES: 0.997 (0.978-1.016)
    Age + SES + COPD:
    0.989(0.970-1.008)
    Risk estimate for increase in mortality
    per increase in PM25, ages 65-74
    Eastern Region
    Age: 31.1(26.8-35.5)
    Age + SES: 17.3 (14.6-20.0)
    Age + SES + COPD: 11.4 (8.8-14.1)
    Central Region
    Age: 39.0 (29.7-48.2)
    Age + SES: 16.5 (10.9-22.1)
    Age + SES + COPD: 20.4 (15.0-25.8)
    Western Region
    Age: 6.0 (2.3-9.6)
    Age + SES:-2.1 (-5.0-0.8)
    Age + SES + COPD:-1.5 (-4.2-1.1)
    Risk estimate for increase in mortality
    per increase in PM25, ages 75-84
    Eastern Region
    Age: 17.6 (14.9-20.4)
    Age + SES: 12.4 (10.1-14.6)
    Age + SES + COPD: 8.9 (6.8-11.0)
    Central Region
    Age: 17.5 (12.7-22.2)
    Age + SES: 8.8 (4.6-13.0)
    Age + SES + COPD: 12.0 (7.6-16.4)
    Western Region
    Age: 0.4 (-2.0-2.7)
    Age + SES: 0.3 (-1.8-2.5)
    Age + SES + COPD:-0.2 (-2.2-1.9)
    Risk estimate for increase in mortality
    per increase in PM25, aged >85
    Eastern Region
    Age:-1.4 (-3.5-0.8)
    Age + SES: 1.4 (-0.7-3.5)
    Age + SES + COPD: 1.7 (-0.3-3.7)
    Central Region
    Age:-2.1 (-5.9-1.6)
    Age + SES: -0.7 (-4.2-2.8)
    Age + SES + COPD: -0.3 (-4.0-3.3)
    Western Region
    Age: -5.2 (-7.2-3.2)
    Age + SES: 0.9 (-0.8-2.7)
    Age + SES + COPD:-0.5 (-2.5-1.5)
     All units expressed in pg/m unless otherwise specified.
    December 2009
                                    E-520
    

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    Table E-34.    Long-term exposure - central nervous system outcomes -  PM.
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
    Author: Calderon-Garciduenas et al.
    (2008, 1923691
    
    Period of Study: NR
    
    Location: Mexico City (polluted city)
    and Tlaxcala and Veracruz (control
    cities), Mexico
    Outcome (ICD9 and ICD10): COX2
    (cyclooxygenase), IL-lp, CD14 in lungs,
    OB (olfactory bulb), frontal cortex,
    hippocampus, substantia nigrae,
    periaqueductal gray and vagus nerves
    
    Age Groups Analyzed:
    
    Subjects 2-45 yr of age
    
    mean=25.1 + 1.5yr
    
    Study Design:
    
    Cross-sectional
    
    N: 47 deceased subjects with complete
    autopsies and neuropathological
    examinations (each subject had to be
    considered clinically healthy and
    cognitively and neurologically intact
    prior to death) (primarily cause of death:
    accidents resulting in immediate death)
    
    Statistical Analyses: NR
    
    likely used T-tests
    
    in addition, stated using "parametric
    procedure that considers the
    differences among variances of the
    variables of interest"
    
    Covariates: Age,  gender, place of birth,
    place of residency, occupation, smoking
    habits, clinical histories, cause of death,
    and time between death and autopsy
    
    Season: NR
    
    Dose-response Investigated?
    (Yes/No): No
    
    Statistical package: Stata
    PM Size: No measure of PM
    
    used Mexico City as the "polluted city"
    and Tlaxcala and Veracruz as the
    "control cities"
    
    Averaging Time: NA
    
    Mean (SD): NA
    
    Percentiles: NA
    
    Range (Min, Max): NA
    
    Unit(i.e. ug/m3): NA
    
    Number of Monitoring Stations: NA
    
    Co-pollutant (correlation):
    
    NA
    PM Increment: NA
    
    Effect Estimate [Lower Cl, Upper Cl]:
    
    RT-PCR sample results from Control
    and Mexico City (MC) lung, CMS, PNS
    (peripheral nervous system) tissues and
    p-value for the difference between the
                                                                                                             Concentrations are normalized to the
                                                                                                             amount of GAPDHcDNA
                                                                                                             COX2 (cyclooxygenase-2) lung
                                                                                                             Controls: 15.9+6.7x106
                                                                                                             MC residents: 42.3+7.4x106
                                                                                                             P-value: 0.015
                                                                                                             IL-1|3lung
                                                                                                             Controls: 3.08+1.87x106
                                                                                                             MC residents: 4.51+2.6x106
                                                                                                             P-value: 0.60
                                                                                                             COX2 OB (olfactory bulb)
                                                                                                             Controls: 12.9+.Ox 105
                                                                                                             MC residents: 38.7+5.5x105
                                                                                                             P-value: 0.0002
                                                                                                             IL-1POB
                                                                                                             Controls: 3.4+0.8x104
                                                                                                             MC residents: 7.7+1.0x104
                                                                                                             P-value: 0.003
                                                                                                             CD140B
                                                                                                             Controls: 0.01+ 0.001
                                                                                                             MC residents: 0.04+ 0.01
                                                                                                             P-value: 0.04
                                                                                                             COX2 frontal
                                                                                                             Controls: 2.6+0.4x105
                                                                                                             MC residents: 5.0+0.7x105
                                                                                                             P-value: 0.008
                                                                                                             IL-1P frontal
                                                                                                             Controls: 0.6+0.2x104
                                                                                                             MC residents: 6.2+1.3x104
                                                                                                             P-value: 0.0002
                                                                                                             COX2 hippocampus
                                                                                                             Controls: 1.9+0.5x105
                                                                                                             MC residents: 1.6+8.7x105
                                                                                                             P-value: 0.1
                                                                                                             IL-lp hippocampus
                                                                                                             Controls: 1.8+0.2x104
                                                                                                             MC residents: 3.0+0.5x104
                                                                                                             P-value: 0.06
                                                                                                             COX2 substantia nigrae
                                                                                                             Controls: 0.16+0.06
                                                                                                             MC residents: 0.97+ 0.2
                                                                                                             P-value: 0.03
                                                                                                             IL-1|3substanita nigrae
                                                                                                             Controls: 0.01+ 0.005
                                                                                                             MC residents: 0.09+ 0.03
                                                                                                             P-value: 0.06
                                                                                                             CD14 substantia nigrae
                                                                                                             Controls: 0.02+ 0.005
                                                                                                             MC residents: 0.03+ 0.007
                                                                                                             P-value: 0.7
                                                                                                             COX2 periaqueductal gray
                                                                                                             Controls: 0.10+0.03
                                                                                                             MC residents: 0.45+0.12
                                                                                                             P-value: 0.12
                                                                                                             IL-1p periaqueductal gray
                                                                                                             Controls: 0.009+ 0.003
                                                                                                             MC residents: 0.07+ 0.02
                                                                                                             P-value: 0.09
                                                                                                             COX2 left vagus
                                                                                                             Controls: 0.65+0.18
                                                                                                             MC residents: 2.68+ 0.82
                                                                                                             P-value: 0.03
                                                                                                             COX2 right vagus
                                                                                                             Controls: 0.43+ 0.09
    December 2009
                                    E-521
    

    -------
                  Study
           Design & Methods
            Concentrations1
       Effect Estimates (95% Cl)
                                                                                                               MC residents: 3.68+ 0.8
                                                                                                               P-value: 0.0002
                                                                                                               IL-1P left vagus
                                                                                                               Controls: 0.1 ±0.03
                                                                                                               MC residents: 1.3+0.73
                                                                                                               P-value: 0.06
                                                                                                               IL-1 p right vagus
                                                                                                               Controls: 0.15+0.09
                                                                                                               MC residents: 0.87+ 0.53
                                                                                                               p-value: 0.66
                                                                                                               CD14 left vagus
                                                                                                               Controls: 0.07+ 0.01
                                                                                                               MC residents: 0.79+ 0.41
                                                                                                               P-value: 0.01
                                                                                                               CD14 right vagus
                                                                                                               Controls: 0.05+ 0.01
                                                                                                               MC residents: 0.31+0.1
                                                                                                               P-value: 0.02
                                                                                                               Distribution of subjects with expression
                                                                                                               of A|342 as a function of age and
                                                                                                               residency
                                                                                                               Groups: No (%) with A|342 expression
                                                                                                               Controls <25yrAPOE 3/3
                                                                                                               Controls >25yrAPOE 3/3
                                                                                                  n=6
                                                                                                  n=3
                                                                   :0(0
                                                                   :0(0
                                                                                                               MC E2 or E3<25yr(n=17):10(58.82)
                                                                                                               MCE2orE3>25yr(n=10):8(80)
                                                                                                               MCE4(n=8):8(100)
                                                                                                               Controls E4(n=3): 2 (66)
                                                                                                               Distribution of subjects with expression
                                                                                                               of a-synuclein as a function of age and
                                                                                                               Residency
                                                                                                               Groups:  No (%) with a-synuclein
                                                                                                               expression
                                                                                                               Controls <25yr APOE 3/3 (n=6): 0 (0)
                                                                                                               Controls >25yr APOE 3/3  n=3: 0 (0)
                                                                                                               MCE2orE3<25yr(n=17):4(23.5)
                                                                                                               MCE2orE3>25yr(n=10):3(30)
                                                                                                               MC E4 (n=8): 2 (25)
                                                                                                               Controls E4 (n=3): 0 (0)	
    Reference: Chen and Schwartz (2009,
    1799451
    
    Period of Study: 1989-1991
    
    Location: U.S.
    Outcome: Change in central nervous
    system function
    
    Study Design: Panel
    
    Covariates: Age, sex, race/ethnicity,
    individual socioeconomic position,
    lifestyle factors, household and
    neighborhood characteristics,
    conventional CVD risk factors
    
    Statistical Analysis: Pearson Chi-
    square tests and t-tests, as appropriate
    
    Statistical Package: STATA
    
    Age Groups: 20-59 yr
    Pollutant: PM,0
    
    Averaging Time: 1 yr
    
    Mean (SD) Unit: 37.2 + 12.8 pg/m3
    
    Copollutant: 0;
    Increment: 10|jg/m
    
    Regression Coefficient p (96% Cl)
    Crude
    SRTT: 2.14 (-0.08-4.36)
    SDST: 0.08 (0.04-0.13)
    SDLT Trials: 0.22 (0.13-0.31)
    SDLT Total: 0.44 (0.23-0.65)
    Model 1: adjusted forage, sex,
    race/ethnicity
    SRTT: 2.03 (-0.15-4.20)
    SDST: 0.10(0.05-0.15)
    SDLT Trials: 0.23 (0.14-0.32)
    SDLT Total: 0.48 (0.27-0.68)
    Model 2: Model 1 + socioeconomic
    factors
    SRTT:-0.11 (-2.38-2.16)
    SDST: 0.01 (-0.04-0.06)
    SDLT Trials: 0.01 (-0.08-0.10)
    SDLT Total:-0.07 (-0.27-0.13)
    Model 3: Model 2 + lifestyle factors
    SRTT:-0.36 (-2.58-1.85)
    SDST: 0.00 (-0.04-0.05)
    SDLT Trials: 0.09 (0.00-0.17)
    SDLT Total: 0.12 (-0.07-0.31)
    December 2009
                                    E-522
    

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                   Study
            Design & Methods
             Concentrations1
        Effect Estimates (95% Cl)
    Author: Suglia et al. (2008,1570271     Outcome (ICD9 and ICD10):
    Period of Study: 1986-2001
    
    Location: Boston, Massachusetts
    Cognition:
    
    Kaufman Brief Intelligence Test, K-BIT
    (vocabulary and matrices subscales
    and composite IQ score)
    
    Wide Range Assessment of Memory
    and Learning, WRAML (psychometric
    instrument with subscales on verbal
    memory, visual memory, learning, and
    overall general index scale)
    
    All cognition scores have a  mean of 100
    andSD=15.
    
    Age Groups Analyzed: Cognitive tests
    administered when children were 8-11
    yr of age
    
    Study Design: Cross-sectional
    
    N: 202 children
    
    Statistical Analyses: Linear regression
    
    Covariates: Child's age at cognitive
    assessment, gender, primary language
    spoken at home,  and maternal
    education (model 1
    
    "Demographic factors")
    
    Sensitivity analyses performed with
    further adjustment for in-utero and
    postnatal secondhand tobacco smoke
    exposure (via questionnaire during
    follow-ups and urinary cotinine levels)
    (model 2)
    
    Birth weight (model 3) and blood lead
    level (model 4)
    
    Season: Separate land-use regression
    models were fit for the warm (May-Oct)
    and cold (Nov-Apr) seasons
    
    Used avg of two seasons as measure
    of avg lifetime BC exposure
    
    Dose-response Investigated?
    (Yes/No): No
    
    Statistical package: SAS (v9.0)
    PM Size: Black carbon (BC)
    
    Averaging Time: Lifetime exposure
    
    Estimated 24 h measures of traffic
    using a spatiotemporal land-use
    regression model using data from >80
    locations in Greater Boston (6021
    pollution measurements from 2127
    unique exposure days)
    
    Predictors in the land-use regression
    analysis were the BC level at a central
    station (to capture avg  concentrations
    on that day), meteorological conditions,
    weekday/weekend, and measure of
    traffic activity (CIS-based measures of
    cumulative traffic density within 100m,
    population density, distance to nearest
    major roadway, % urbanization)
    
    Used the avg of the cold and warm
    seasons as the measure of avg lifetime
    BC exposure
    
    Mean (SD): 0.56 (0.13) pg/m3
    
    Percentiles: NR
    
    Range (Min, Max): NR
    
    Unit(i.e. ug/m3):
    
    Number of Monitoring Stations: >80
    locations
    
    Co-pollutant (correlation): NA
    PM Increment: 0.4 pg/m
    
    Effect Estimate [Lower Cl, Upper Cl]:
    Change in subscale score (95%CI) per
    IQR (0.4 pg/m3) increase in log BC level
    K-BIT
    Vocabulary:
    Adj for demographic factors: -2.0 (-5.3,
    1.3)
    Adj for above factors + secondhand
    smoke:-2.0 (-5.3,1.4)
    Adj for above factors + birth weight:  -
    2.0 (-5.4,1.3)
    Adj for above factors + blood lead  level:
    -2.2 (-5.5,  1.1)
    Matrices:
    Adj for demographic factors:
    -4.2 (-7.7,  -0.7)
    Adj for above factors + secondhand
    smoke: -4.0 (-7.5, -0.4)
    Adj for above factors + birth weight:
    -4.0 (-7.6,  -0.5)
    Adj for above factors + blood lead  level:
    -4.0 (-7.6,  -0.5)
    Composite:
    Adj for demographic factors:
    -3.4 (-6.6,  -0.3)
    Adj for above factors + secondhand
    smoke:-3.3 (-6.4,-0.1)
    Adj for above factors + birth weight:
    -3.3 (-6.5,  -0.2)
    Adj for above factors + blood lead  level:
    -3.4 (-6.6,  -0.3)
    WRAML
    Verbal:
    Adj for demographic factors:
    -1.1 (-4.6, 2.3)
    Adj for above factors + secondhand
    smoke:-1.2 (-4.7, 2.3)
    Adj for above factors + birth weight:
    -1.3 (-4.7,  2.2)
    Adj for above factors + blood lead  level:
    -1.3 (-4.8,  2.2)
    Visual:
    Adj for demographic factors:
    -5.2 (-8.6,-1.7)
    Adj for above factors + secondhand
    smoke:-5.3 (-8.8,-1.8)
    Adj for above factors + birth weight:
    -5.3 (-8.8,-1.8)
    Adj for above factors + blood lead  level:
    -5.4 (-8.9,-1.9)
    Learning:
    Adj for demographic factors:
    -2.7 (-6.5,  1.1)
    Adj for above factors + secondhand
    smoke:-2.6 (-6.5,1.2)
    Adj for above factors + birth weight:
    -2.6 (-6.5,1.3)
    Adj for above factors + blood lead  level:
    -2.8 (-6.6,  1.1)
    General:
    Adj for demographic factors:
    -3.7 (-7.2,  -0.2)
    Adj for above factors + secondhand
    smoke:-3.7 (-7.3,-0.1)
    Adj for above factors + birth weight:
    -3.8 (-7.4,  -0.2)
    Adj for above factors + blood lead  level:
    -3.9 (-7.5,  -0.3)	
     All units expressed in pg/m  unless otherwise specified.
    December 2009
                                     E-523
    

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                                        Annex  E  References
    Abbey DE; Nishino N; McDonnell WF; Burchette RJ; Knutsen SF; Beeson WL; Yang JX. (1999). Long-term inhalable
          particles and other air pollutants related to mortality in nonsmokers. Am J Respir Crit Care Med, 159: 373-382.
          047559
    
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           failure in seven United States cities. Am J Cardiol, 97: 404-408. 088748
    
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           functional status in patients with chronic congestive heart failure: a repeated-measures study. Environ Health, 6: 1-
           7. 092830
    
    Welty LJ; Peng RD; Zeger SL; Dominici F. (2008). Bayesian Distributed Lag Models: Estimating Effects of Particulate
           Matter Air Pollution on Daily Mortality. Biometrics, 65: 282-291. 157134
    
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           and Air Pollution study the result of inadequate control for weather and season? A sensitivity analysis using flexible
           distributed lag models. Am J Epidemiol, 162: 80-88. 087484
    
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           560-566. 088453
    
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           188766
    
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           County, California, USA. Environ Health Perspect, 113:  1212-1221. 088668
    
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           17: S11-S19. 157149
    
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           023232
    
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    December 2009                                        E-551
    

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    Wong CM; Ou CQ; Lee NW; Chan KP; Thach TQ; Chau YK; Ho SY; Hedley AJ; Lam TH. (2007). Short-term effects of
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           60: 890-895. 090195
    December 2009                                        E-552
    

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    Reference: Gent et al.
    (2009, 180399)
    Location: 2 monitors in
    New Haven, CT/ 3.5 yr
    Particle Size: PM2.5
    
    
    
    
    
    
    
    Subjects: N: 149
    Children with children
    physician
    diagnosed
    asthma and
    symptoms or
    medication use
    in previous 12
    mo, and resided
    within 30km of
    New Haven
    county monitor
    Exposure: NR
    Number of Grouping
    Constituents method: PCA
    considered for
    grouping: 17 # of groups: 6
    elements + EC
    
    
    
    
    
    
    
    
    Groups/Factors/ Sources:
    Vehicle (EC, Zn, Pb.Cu,
    Se), road dust (Si, Fe.AI,
    Ca.Ba.Ti), sulfur (S,P),
    biomass burning, (K) oil (V,
    Ni), sea salt (Na.CI)
    
    In addition, effects of N02,
    CO, S02, and 03 were
    included in the health
    outcomes model
    
    
    PM variables used:
    Groupings and
    individual elements
    
    
    
    
    
    
    
    
                              Results: Overall: Trace elements originating from motor vehicle, road dust, biomass burning, and oil sources associated with
                              symptoms and/or medication use. No associations with S or sea salt.
    
                              Specific Results: PM2.5 mass from motor vehicle or road dust associated with increased odds of respiratory symptoms or
                              inhaler use. Reduced odds of wheeze or inhaler use with same day S. Significant reductions odds of wheeze with biomass
                              burning.
    
                              Co-pollutant: Positive effects of motor vehicles and road dust on wheeze were robust to the inclusion of gaseous copollutants.
                              However, N02 increases association with wheeze.
    Reference: Ito et al. Subjects: NR N: NR
    (2006, 188554)
    Exposure: NR
    Location: Washington,
    DC
    Particle Size: PM25
    
    
    Number of
    Constituents
    considered for
    grouping: NR
    
    
    
    
    Grouping
    method:
    Comparison of:
    PMF; (absolute)
    PCA; UNMIX
    # of groups: 6-10
    Groups/ Factors/
    Sources: Different
    research groups
    gave different
    names to sources
    
    Sources for which
    association with health
    was analyzed: Soil, traffic,
    Secondary S04, N03
    (Washington, DC only),
    residual oil (Washington,
    DC only), Wood smoke/
    biomass combustion, Sea
    salt, incinerator
    (Washington, DC only),
    primary coal (Washington,
    DC only), Cu smelter
    (Phoenix only)
    PM variables used:
    Mass contribution of
    sources
    
    
    
    
                              Results: Overall, PM25 effects observed at lag 3. Lag structure of association varied across source types, but consistent
                              across investigators for total (nonaccidental mortality): soil factor - mostly positive at various lags (not significant); secondary
                              sulfate - strongest association at lag 3; nitrate - mostly negative except at lag 3; residual oil - strongest association at lag 2 (not
                              significant); wood-burning - increasing association as lag increases (not significant); incinerator - significant negative
                              associations at lag 0; primary coal- significant association at lag 3.
    Reference: Laden et al.
    (2000, 012102)
    
    Location: Monitors in 6
    Eastern US cities (Harvard
    Six Cities Study)
    
    Particle Size: NR
    Subjects: NR     N: NR
    
    Exposure: NR
    Number of        Grouping
    Constituents      method: PCA
    considered for
    grouping: 15      # of groups: 8
    elements
    Groups/ Factors/ Sources:  PM variables used:
    Soil/crustal (PM fine),        Tracers: Si, V, Cl, Pb,
    mobile vehicle exhaust (PM  Se
    fine), coal  (PM fine), fuel oil;
    metals, salt manganese,
    residual
                              Results: Lag 0-1 avg for all results. Overall 6 cities, mobile source factor (using Pb as tracer) had greatest association with
                              daily mortality (3.4%) with 10 ug/m3 increase. The greatest effects for mortality due to mobile sources were observed in
                              Madison (Portage), Knoxville (Kingston-Harriman), and St. Louis, although the Madison results were not statistically significant.
                              The coal source factor was only significant in Boston (Watertown) - 2.8% increase in mortality and the overall percent increase
                              was also significant (1.1%). Deaths from pneumonia attributable to coal combustion sources was 7.9% (Cl 3.1-12.7%) and
                              statistically significant. The crustal factor was not associated with mortality in any city, although this factor was not a significant
                              predictor in the regression model for Boston (Watertown) due to its low contribution to PM2.5 mass. For specific elements
                              included simultaneously, S, Pb, and Ni were significantly associated with overall mortality (3.0,1.6,1.5%, respectively). Boston
                              had the greatest percent increase in  mortality for S (7.9%), Knoxville for Pb (15.0%), and Steubenville for Ni (8.2%), although
                              the CIs are all quite large.
    
                              Reanalysis results: (Schwartz, 2003, 042811) Effects changed slightly. New percent increases in mortality for combined cities
                              are 3.5 and 0.79 for traffic and coal, respectively. The coal factor in Boston decreased to 2.1 % increased mortality. A residual
                              oil factor in Boston and Steubenville resulted in at 22.9% increase in daily deaths (but was not significant in the original
                              analysis).
    Reference: Lanki et al.
    (2006, 088412)
    Location: Monitors in
    Helsinki, Finland,
    Amsterdam,The
    Netherlands and Erfurt,
    Germany
    Subjects: NR
    Exposure: NR
    N:NR
    Number of
    Constituents
    considered for
    grouping: 13
    elements
    Grouping
    method: Absolute
    PCA
    # of groups: 5
    Groups/ Factors/ Sources:
    Crustal; long range
    transported; oil combustion;
    soil; traffic
    Results: Highest observed effects were for crustal sources and salt at lag 3 (when analyzing sources),
    PM variables used:
    Tracers: Si (crusta I) ;S
    (long-range transport);
    Ni (oil combustion) ;CI
    (salt) ;ABS (local
    traffic).
    but not consistent or
                 .._,_..       significant. In multipollutant models only ABS associated with ST-segment depression, but wide CIs. When examining indicator
    Particle Size: UF/PM2 5     elements of a source, local traffic found to be the most toxic, but when examined per IQR long-range transport and traffic had
                              similar effects.
    December 2009
                                               F-2
    

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                              Results: All had significant associations with mortality. Traffic density and EC had the largest effects.
    Reference: Lippmann et
    al. (2006.091165)
    Location: U.S.
    Subjects: NR N: NR
    Exposure: NR
    Number of
    Constituents
    considered for
    grouping: NR
    Grouping
    method: No
    grouping was
    performed
    Groups/ Factors/ Sources:
    NR
    PM variables used:
    Mass contribution of
    16 constituents
    Particle Size: PM10 for risk
    estimates, PM2.5for
    speciation data
                                                   # of groups: NR
    Results: The strongest predictions of the variation in PM10 risk estimates across the 90 NMMAPs MSAs was for Ni and V.
    Elevated, but nonsignificant increases were associated with EC, Zn, S042-, Cu, Pb, and OC. Al and Si had the lowest values.
    Reference: Mar et al.
    (2000, 001760)
    Location: 1 monitor in
    Phoenix, AZ
    
    Particle Size: NR
    Subjects: N: NR
    Elderly only
    Exposure: NR
    
    
    
    Number of
    Constituents
    considered for
    grouping: 10
    elements, OC,
    EC, CO, N02;
    S02
    Grouping
    method:
    Unspecified type of
    factor analysis
    
    # of groups: 3 or 5
    
    Groups/ Factors/ Sources:
    Motor exhaust/road dust,
    soil, vegetative burning,
    local S02, regional S04
    
    
    
    PM variables used:
    First used individual
    constituents: S,Zn,
    Pb, K,OC,EC,TC
    (AL+Si+Ca+Fe+Ti),
    then factor scores
    
                              Results: Cardiovascular mortality associated with PM25 mass on lag 1 and 4 (6 and 4%, respectively). EC and TC associated
                              with CV mortality for lag 1 (RR= 1.05);OC was weakly associated with CV mortality for lags 1 and 3. For total mortality,
                              regional sulfate was positively associated at lag 0, but negatively associated at lag 3. The local S02 and the soil factors were
                              negatively associated with total mortality. For CV  mortality, secondary sulfate was positively associated at lag 0, motor vehicle
                              at lag 1, and vegetative burning at lag 3.
    
                              Reanalysis results (Mar, 2003): Similar associations were observed.
    Reference: Mar et al. Subjects: NR N: NR
    (2006, 086143)
    Exposure: NR
    Location: Phoenix, AZ
    Particle Size: PM25
    
    
    
    Number of
    Constituents
    considered for
    grouping: NR
    
    
    
    
    Grouping
    method:
    Comparison of:
    PMF (absolute);
    PCA; UNMIX
    # of groups: 6-10
    Groups/ Factors/
    Sources: Different
    labs gave different
    names to sources
    (see Hopke et al,
    table 2)
    Sources for which
    association with health was
    analyzed: Soil, Traffic,
    secondary S04, N03,
    (Washington, DC only),
    residual oil (Washington,
    DConly),woodsmoke/
    biomass combustion, sea
    S3 it, incinsrstor
    (Washington, DC only);
    primary coal (Washington,
    DC only) ;Cu smelter
    (Phoenix only)
    PM variables used:
    Mass contribution of
    sources
    
    
    
    
                              Results: Using daily PM25 data found the following associations with cardiovascular mortality: Secondary sulfate - greatest
                              effect observed for all sources and at lag 0; traffic - associated at lag 1; copper smelter associated at lag 0; sea salt - had the
                              greatest statistical significance and observed at lag 5; biomass/wood burning - less consistent lag structure but greatest
                              association at lag 3; soil - did not show an association or consistent lag structure. For total (nonaccidental) mortality
                              associations were weaker and consistently observed for only: copper smelter - lag 0; sea salt - lag 5.
    Reference: Ostro et al.
    (2007, 091354)
    Location: Monitors in 6
    CA counties, some with 2
    monitors, for 4 yr
    Particle Size: PM25
    Subjects NR N: NR
    Exposure: NR
    Number of
    Constituents
    considered for
    grouping: 15
    elements, EC,
    OC;N03;S04,
    PM2.5 mass
    Grouping
    method: No
    grouping was
    performed
    # of groups: NA
    Groups/ Factors/ Sources: PM variables used:
    NR Mass contribution of
    every constituent
                              Results: Effects were greater during the winter months. In the all year analysis, at 3-day lag associations observed for EC, OC,
                              N03 and Zn. During winter months (Oct -March) effects observed for most species for both all-cause and cardiovascular
                              mortality at lag 3 (EC, OC, S04, Ca, Fe, K, Mn, Pb, S, Si, Ti, Zn) and (OC, N03, S04, Fe, Mn, S, V, Zn), respectively.
    Reference: Ostro et al.
    (2009,191971)
    Location: Monitors in 6
    CA counties, some with 2
    monitors/4 yr
    Particle Size: PM25
    Subjects NR N: NR
    
    Exposure: NR
    
    
    Number of
    Constituents
    considered for
    grouping: 9
    elements, EC, OC,
    PM25mass,S04,
    N03
    Grouping
    method: No
    grouping was
    performed
    # of groups: NA
    
    Groups/ Factors/ Sources:
    NR
    
    
    
    PM variables used:
    Mass contribution of
    every constituent
    
    
                              Results: The following associations were observed with cardiovascular mortality: PM25 (lag 3); EC (lag 2); N03 (lag 3); S04
                              (lag 3); Fe (lag 2); K (lag 2); S (lag 3); Ti (lag 2); Zn (lag 3).
    December 2009
                                              F-3
    

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    Reference: Peng et al.
    (2009,191998)
    
    Location: 119 urban
    communities STN
    data/2000-2006
    
    Particle Size: PM25
    Subjects:
    Medicare
    enrollees 65 or
    older
    
    Exposure: NR
                    N:NR
    Number of
    Constituents
    considered for
    grouping: S04,
    N03,Si, EC,
    OCM, Na, NH4
    Grouping
    method: NR
    
    # of groups: NR
    Groups/Factors/ Sources:   PM variables used:
    Only suggested in           Tracers
    discussion
                            Results: CVD HAs: EC associated with same-day CVD HAs in single and multi-pollutant models. In single pollutant models
                            associations also observed for sulfate, nitrate, OCM, and ammonium. However, the sulfate, nitrate, OCM, and ammonium
                            associations were reduced in the multi-pollutant models.
    
                            Respiratory HAs: OCM associated with same-day respiratory HAs in single and multi-pollutant models. Some evidence for
                            sulfate associations at one and two-day lag.
    Reference: Penttinen et
    al. (2006, 087988)
    Location: Helsinki
    1996-1 997 (7 mo)
    Particle Size: PM2.5
    Subjects: Adult N: 78
    asthma subjects,
    max 2 km from
    single monitor
    Exposure: NR
    Number of
    Constituents
    considered for
    grouping:
    Unknown
    
    Grouping
    method: PCA
    # of groups: 6
    
    Groups/Factors/ Sources:
    Long range (PM mass, S,
    K,Zn), local
    combustion-traffic (Cu, Zn,
    Mn,Fe),soil(Si,AI, Ca, Fe,
    Mn), oil (V, Ni), salt (Na, Cl),
    unidentified
    PM variables used:
    every component
    individually, then
    groupings
    
                            Results: Long range PM2.5 associated with decreased mean PEF in the morning at lag 1. Local combustion PM2.5 associated
                            with decreased mean PEF in the evening for lag 1. Local combustion PM2.5 associated with decreased mean PEF in the
                            afternoon and evening for 5-day mean lag. Negative significant association between long-range PM2 5 and asthma symptom
                            prevalence at lag 3. Sea-salt PM25 negatively associated with bronchodilator use at lag 3 and 5-day mean lag. Sea-salt PM25
                            negatively associated with corticosteroid use for 5-day mean lag. Unidentified PM25 negatively associated with corticosteroid
                            use at lag 1.  Most consistent negative responses for local combustion, although not always significant. No consistent or
                            significant associations between 5-day avg concentrations of elements and PEF, cough, asthma symptoms, or medication use.
    Reference: Riediker et al.
    (2004, 091261)
    Location: Inside 9 state
    police patrol cars
    Particle Size: PM25
    Subjects: N: 9
    Healthy male
    young police
    officers
    Exposure: 4
    consecutive days
    Number of Grouping Groups/ Factors/ Sources:
    Constituents method: PCA Soil; automotive steel wear;
    considered for gasoline combustion;
    grouping: 10 #of groups: 4 speed-changing traffic
    elements; 3 when 13+2
    gaseous constituents
    pollutants; 2 included; 3 when
    physical variables on|y9
    "PM-associated"
    constituents
    included
    PM variables used:
    Mass contribution or
    score of sources
    Results: Using two different factor analysis models found most significant effects (MCL, SDNN, PNN50, supraventricular
    ectopic beats, % neutrophils, % lymphocytes, MCV, von Willebrand Factor, and protein C) were for "speed-change factor" (i.e.,
    Cu, S, aldehydes). Some associations observed for "crustal" and none for "steel wear" and "gasoline."
    Reference: Sarnat et al.
    (2008, 097972)
    Location: 1 monitor in
    Atlanta. GA for 2 yr
    Particle Size: PM25
    Subjects: NR N: NR
    Exposure: NR
    Number of Grouping Groups/ Factors/ Sources:
    Constituents method: gasoline, diesel, wood
    considered for Comparison of: smoke/ biomass burning,
    grouping: NR PMF, CMB-LGO, "a soil, secondary
    priori decision" S04/ammonium sulfate,
    secondary nitrate/
    # of groups: 9,11 ammonium nitrate, metal
    (6 of them common processing, railroad, bus
    between methods) anc| highway, cement kiln,
    power plants, other OC,
    ammonium bisulfate
    PM variables used:
    Mass contribution or
    score of sources, and
    tracers
                            Results: Sulfate secondary associated with 1.2-2.0% increase in RD visits, significant negative association RD visits and
                            primary emissions from coal-fired power plants. CVD significantly associated with other OC (1.014), biomass (1.033), diesel
                            and gas for CMB-LGO. For PMF and CVD visits: diesel (1.025), gas, wood smoke, metal processing (1.013). Year-long
                            associations: PMF diesel, EC, CMB-LGO gas, Zn and biomass combustion sources (CMB-LGO biomass burning, PMF wood
                            smoke, and K). Diesel and gas sources association with RD in the warm season (1.2-2.1% per IQR).
    Reference: Schreuder et
    al. (2006. 097959)
    
    Location: 1 monitor in
    Spokane, WA for 7 yr
    
    Particle Size: PM25
    Subjects: NR
    
    Exposure: NR
                                             N:NR
    Number of
    Constituents
    considered for
    grouping: 11
    elements,TC,
    N03
    Grouping
    method:
    Comparison of:
    PMF, UNMIX,
    Multilinear Engine
    
    # of groups: 8
    Groups/ Factors/ Sources:  PM variables used
    Vegetative burning; As-rich   Tracers:TC
    Vehicle; S04;N03; Soil;
    Cu-rich; Marine
                                                                                             (vegetative burning);
                                                                                             As (As-rich) ;Zn
                                                                                             (vehicle); Si (soil)
                            Results: Si, As, and Zn were not associated with any health outcomes; while an IQR increase in TC (vegetative burning) was
                            associated with a 2% increase in respiratory ED visits.
    December 2009
                                             F-4
    

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    Reference: Tsai et al.
    (2000,006251)
    Location: 3 NJ sites for 2
    summers (ATEOS study)
    Particle Size: NR
    Subjects: NR N: NR
    
    Exposure: NR
    
    Number of
    Constituents
    considered for
    grouping: 8
    metals, IPM,
    FPM,S04,CX,
    DCM.ACE.CO
    Grouping
    method:
    Unspecified type of
    factor analysis
    # of groups: 5
    Groups/ Factors/ Sources:
    Oil burning, motor
    emissions, resuspended
    dust, secondary aerosol,
    industrial sources
    
    PM variables used:
    individual constituents,
    then factor scores,
    then tracers
    
                              Results: RR associated with 10 ug/m3 increases: Newark -1.03 for industrial and total daily deaths; 1.02 for sulfate and total
                              daily deaths; 1.04 for sulfate and cardiopulmonary deaths. Camden-1.11 for oil burning sources and total daily deaths; 1.10
                              industrial and total daily deaths; 1.12 for oil burning sources and cardiopulmonary daily deaths; 1.02 for sulfate and
                              cardiopulmonary daily deaths
    Reference: Yue et al.
    (2007, 097968)
    
    Location: 1 monitor in
    German city, 30.000
    samples
    Particle Size: UF/PM25
    
    Subjects: Adult
    males
    
    Exposure: CAD
    
    
    
    
    n: 56, data
    collected 12
    times over 6
    mo for every
    subject, but
    extended
    period of
    missing PM
    data
    Number of
    Constituents
    considered for
    grouping:
    Apportionment
    based on particle
    size distribution.
    
    Grouping
    method: PMF
    
    # of groups: 5
    
    
    
    
    Groups/ Factors/ Sources:
    Airborne soil, local traffic,
    local fuel combustion,
    remote traffic (diesel),
    secondary aerosols
    
    
    
    PM variables used:
    Mass contribution or
    score of sources
    
    
    
    
    
                              Results: Overall, repolarization parameters influenced by traffic-related particles; vWF increased in response to traffic-related
                              particles and combustion-generated aerosols. All source factors contributed to increasing CRP levels.
    December 2009
    F-5
    

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    Table F-2.    Human clinical studies of ambient PM sources, factors, or constituents
    Study: Gong et al.
    (2003, 042106)
    Location: Los
    Angeles, CA
    Particle Size: PM25
    Study: Gong et al.
    (2005, 087921)
    Location: Los
    Angeles, CA
    Particle Size: PM2.5
    Reference: Huang
    etal.(2003,
    087377)
    Location: Chapel
    Hill, NC
    Particle Size: PM2.5
    Reference: Urch et
    al. (2004, 055629)
    Location: Toronto,
    Canada
    Particle Size: PM25
    Reference: Urch et
    al. (2004, 055629)
    Location: Toronto,
    Canada
    Particle Size: PM25
    Subjects: Adult N: 12 healthy, 12 Constituents Grouping method: Groups/ Factors/ PM variables used:
    18-45, healthy vs. asthmatic considered for PCA Sources: Crustal (Al Total mass, then
    asthmatic grouping: 7 SiCAKFe),S(2 tracers: S04, EC, Fe
    elements, EC, N03, #of groups: 4 metrics of S04 +
    Exposure: CAPs, sc,4 (note :OC data was elemental S) Total
    healthy and unavailable) Mass+N03, EC
    asthmatic subjects
    exposed at different
    times
    Results: Fe and EC associated with a decrease in ST-segment voltage 2 days post-exposure. EC associated with an increase in
    ST-segment voltage immediately following exposure. Sulfate content associated with a decrease in systolic BP 4 h post-exposure.
    Subjects: Elderly, N: 6 healthy, 18 Constituents Grouping method: Groups/ Factors/ PM variables used:
    COPD vs. healthy/ COPD considered for PCA Sources: Crustal (Al Total mass, then
    CAPs grouping: 7 SiCAKFe), tracers:, S04, Si, Fe,
    elements # of groups: 3 S(=S04),Na EC
    Exposure: N02 (full + EC (note: OC was
    factorial) unavailable)
    Results: Mass concentration of CAPs not observed to significantly affect lung function. However, sulfate content was associated with
    a decrease lung function (FEV, and FVC), which was enhanced by coexposure to N02.
    Subjects: Healthy N: 35 male; 2 female Constituents Grouping method: Groups/ Factors/ PM variables used:
    adults considered for PCA Sources: Factor scores, then
    grouping: 8 Fe/S04/Se/V/Zn/Cu mass contribution of
    Exposure: CAPs elements and S04 # of groups: 2 all 9 constituents
    Results: Associations observed between sulfate ,Zn, and Se content and increases in BAL neutrophils. Increases in fibrinogen
    associated with Cu, Zn, and V content.
    Subjects: Healthy N: 23 Constituents Grouping method: Groups/ Factors/ PM variables used:
    adults considered for No grouping was Sources: NR Every constituent in
    19-50 yr/CAPs grouping: unknown performed univariate analysis,
    then OC and S04 in
    Exposure: 03 # of groups: NA multivariate analysis
    Results: CAPs-induced increase in diastolic BP significantly associated with carbon content of the particles.
    Subjects: Healthy N: 24 Constituents Grouping method: Groups/ Factors/ PM variables used:
    adults/CAPs considered for No grouping was Sources: NR Every constituent in
    grouping: 14 performed univariate analysis,
    Exposure: 03 elements, EC, OC then OC and S04 in
    # of groups: NA multivariate analysis
    Results: Both organic and EC content of CAPs associated with an increase in brachial artery vasoconstriction.
    December 2009
    F-6
    

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    Table F-3.      Toxicological studies of ambient PM sources, factors, or constituents
    Reference:
    Batalha et al.
    (2002, 088109)
    Location:
    Boston, MA
    Particle Size:
    PM2.5
    Reference:
    Becker et al.
    (2005, 088590)
    Location:
    Chapel Hill, NC;
    repeated
    sampling for 1 yr
    Particle Size:
    PM10
    Reference:
    Clarke et al.
    (2000, 013252)
    Location:
    Boston, MA
    Particle Size:
    PM,,
    Subjects: Rats N: 7-10 rats * Constituents Grouping Groups/ Factors/ Sources: V/Ni, PM variables
    2 levels CAPs considered for method: S,AI/Si, Br/Pb used: 4 tracers (Si,
    Exposure: CAPs x 2 levels S02 grouping: 20 Previous study S04,V, Pb) and
    (3-day mean CAPs x 6 runs in elements ;OC; EC in same city EC.OCin
    concentration range: different (Clarke et al., univariate step. 4
    126.1 -481 .Oug/m3) seasons 2000.013252) tracers (Si, S04, V,
    CAPs (3-day mean anc| RCA of this Pb) in multivariate
    CAPs concentration experiment's step
    range: data
    126.1 -481 .Oug/m3)
    # of groups: 4
    Results: Univariate analyses for first day not significant for UW ratio. Univariate analyses for second and third day and second+third day
    mean were similar. Presented second+third day mean regression data. CAPs mass, Si, Pb, S04, EC, OC significant for decreased L/W
    ratio in normal+CB rats exposed to CAPs. Si, S04 significant for decreased L/W ratio in normal rats. Si, OC significant for decreased UW
    ratio in CB rats. Multivariate analysis using normal+CB rats for Si, S04, V, Pb - only Si remained significant with decreased L/W ratio.
    Subjects: Normal N: NR Constituents Grouping Groups/ Factors/ Sources: PM variables
    human bronchial considered for method: PCA Cr/AI/Si/Ti/Fe/Cu ("crustal"), used:NR
    epithelial and human grouping: 12 Zn/As/V/Ni/Pb/
    AM elements # of groups: 2 Se
    Exposure: (2-3X105
    cells/mL;11 or 50
    ug/mL)
    Results: Cr/AI/Si/Ti/Fe/Cu associated with IL-8 release in normal human bronchial epithelial cells and IL-6 release in AM.
    Zn/As/V/Ni/Pb/Se not associated with any endpoints. Stepwise linear regression with individual constituents Fe and Si associated with
    IL-6 release in AM. Cr associated with IL-8 release in NHBE cells.
    Subjects: Dogs N: 10 dogs, 20 Constituents Grouping Groups/ Factors/ Sources: V/Ni, PM variables
    paired considered for method: PCA S,AI/Si, Br/Pb, S, Na/CI, Cr used: All elements,
    Exposure: CAPs (avg exposures, 24 grouping: 19 then factor scores
    for all studies, paired: crossover elements, black C # of groups: 4
    203.4, crossover: for exposure in
    360.8 ug/m3) repeated paired runs,6 for
    exposure with several exposure in
    weeks in between crossover runs
                    Results: No significant differences between baseline, sham, or CAPs group for BAL cell differential percentages. Total BAL protein
                    increased with CAPs compared to sham. No significant hematological effects with CAPs exposure. Mixed linear regression analyses
                    (statistics not provided): Al and Ti (3-day avg. concentrations) associated with dose-dependent decreases in BAL AM and increases in
                    BAL PMN percentages. Sulfate associated with increased WBC.  BC, Al, Mn, Si, Zn, Ti, V, Fe, Ni associated with increased blood PMN.
                    Na associated with increased blood lymphocytes. Al, Mn, Si associated with decreased blood lymphocytes. CAPs mass and BC
                    associated with decreased blood eosinophils. CAPs mass associated with decreased platelet count. Regression using results of factor
                    analysis: None for 3-day avg. concentration for BAL parameters.  V/Ni for increased AM percentage and Br/Pb for increased PMN
                    percentage for 3rd-day only concentration. V/Ni and Al/Si for increased blood PMN percentage and decreased blood lymphocyte
                    percentage. Al/Si also for increased WBC counts. Na/CI for increased blood lymphocyte percentage. S for decreased RBC and
                    hemoglobin.
    Reference:
    Duvall et al.
    (2008, 097969)
    Location: 5 US
    cities
    Particle Size:
    PM,,
    Subjects Primary N: NR
    human airway
    epithelial cells
    (1 00,000 cells/mL;
    dose not provided)
    Exposure: NR
    Constituents
    considered for
    grouping: NR
    Grouping
    method: CMB,
    but not on
    coarse and
    ultrafine
    # of groups: 6
    or?
    Groups/ Factors/ Sources:
    Mobile, residual, oil, wood, soil,
    secondary S04, secondary N03
    PM variables
    used: Mass
    contribution of
    constituents, then
    mass contribution
    of sources
                    Results: Linear regression with individual constituents: Sulfate associated with increased IL-8 mRNAexpression. Sr associated with
                    increased COX-2 and decreased HO-1 mRNA expressions. K associated with decreased HO-1 mRNA expression.
    
                    Linear regression with sources: Significance levels not provided.
    December 2009
    F-7
    

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    Reference:
    Godleski et al.
    (2002, 156478)
    Location:
    Boston, MA
    Particle Size:
    NR
    Reference:
    Gurgueira et al.
    (2002, 036535)
    Location:
    Boston, MA
    Particle Size:
    PM2.5
    Reference:
    Kodavanti et al.
    (2005, 087946)
    Location: RTP,
    NC
    Particle Size:
    PM2.5
    Reference:
    Lippmannetal.
    (2005, 087453)
    Location: Rural
    location upwind
    from New York
    City
    Particle Size:
    PM2.5
    Reference:
    Lippmann etal.
    (2006, 091165)
    Location: Rural
    location upwind
    from New York
    City
    Particle Size:
    PM2.5
    Subjects: Rats N: 7-10 rats * Constituents Grouping Groups/ Factors/ Sources: V/Ni, PM variables
    2 levels CAPs considered for method: S,AI/Si/Ca, Br/Pb used: 4 tracers (I,
    Exposure: CAPs x 2 levels S02 grouping: 20 Previous study S04,V, Pb) and EC,
    (3-day mean CAPs x 6 runs in elements, OC, EC in same city OC
    concentration range: different (Clarke et al.),
    126.1 -481 .Oug/m3) seasons andPCAofthis
    experiment's
    data
    # of groups: 4
    Results: Increased percent of PMNs in BALF in CAPs-exposed rats at 24 h. CAPs affected lung tissue mRNA involved in
    pro-inflammation, immune, and vascular endothelial responses. Linear regression: Increased PMN associated with CAPs mass, Br, Pb,
    S04, EC, and OC.
    Subjects Rats N: 13 Constituents Grouping Groups/ Factors/ Sources: NR PM variables
    (Sprague Dawley) experiments considered for method: No used: Mass
    (1 rat/group at grouping: 20 grouping was contribution of
    Exposure: CAPs (avg. each time elements performed every constituent
    mass concentration no'ml)
    600 ug/m3); also #of groups: NA
    carbon black and
    ROFA
    Results: Increased oxidative stress in heart and lungs following CAPs exposure (and ROFA exposure).
    Univariate regression: Mn, Zn, Fe, Cu, and Ca most significant responses for lung (r2>0.40). Al, Si, Ti, Fe, and total mass most significant
    response for heart (r >0.49).
    Subjects Rats (SH and N: 6 1-day, Constituents Grouping Groups/ Factors/ Sources: NR PM variables
    l/VKY) 1-strain runs, considered for method: No used: Mass
    72-day, grouping : NR grouping was contribution of
    Exposure: CAPs 2-strain runs, performed every constituent
    (1 44-2758 ug/m3) 4-9 rats per
    run # of groups: NA
    Results: No significant correlations between biologic responses and exposure variables (i.e., CAP mass, OC, inorganic C, sulfate, and
    other major elemental constituents). Al, Cu, Zn correlated with biologic responses when constituents normalized per unit mass of CAP
    (ug/mg). Zn correlated with plasma fibrinogen in SH rats (p = 0.0023).
    Subjects: Mice (C57 N:C57:3-6 Constituents Grouping Groups/ Factors/ Sources: PM variables
    andApoE) mice/group considered for method: Regional S04(S/Si/OC); used: Mass
    , grouping: 19 (Absolute) PCA Resuspended soil contribution of
    Exposure: CAPs (avg. ApoE: 9-10 elements + OC, EC, (CA/Fe/AI/Si);RO power plants sources
    mass concentration mice/group njo3 # of groups: 4 (V/Ni/SeV
    1 1 3 ug/m3) traffic and unknown
    Results: ApoE null mice: Resuspended soil associated with decreased HR during exposure, but increased HR after exposure.
    Secondary sulfate associated with decreased HR after exposure. Residual oil associated with increased RMSSD and SDNN in afternoon
    following exposure. Secondary sulfate associated with decreased RMSSD and SDNN in night following exposure. Resuspended soil
    associated with increased RMSSD at night following exposure. PM mass associated with decreased HR during exposure and decreased
    RMSSD at night following exposure.
    C57 mice: Motor vehicle/other source category associated with decrease in RMSSD in afternoon following exposure
    Subjects: Mice N: 12 ApoE''' Number of Grouping Groups/ Factors/ Sources: NR PM variables
    (ApoE") mice (6/group) Constituents method: No used: Mass
    considered for grouping was contribution of
    Exposure: CAPs (avg. grouping: NR performed every constituent in
    mass concentration CAPs portion of
    85.6 ug/m ) # of groups: NR study contribution
    of 16 constituents
    in epi portion
    Results: Lag for HR elevations on 14 days with wind from NWwas same day. Lag for SDNN reduction on 14 days with wind from NW
    was 0, 1 and 2.
    GAM analysis: B coefficient significant for Ni and HR (but not V, Cr, or Fe). B coefficient significant for Ni and log SDNN (but not V, Cr, or
    Fe).
    December 2009
    F-8
    

    -------
    Reference:
    Maciejczyk and
    Chen (2005,
    087456)
    Location: Rural;
    Subjects: NR
    Exposure: CAPs
    (90,000/well;300
    ug/mL)
    N:110
    samples
    Constituents
    considered for
    grouping: 19
    elements + OC, EC,
    N03
    Grouping
    method:
    (Absolute) PCA
    # of groups: 4
    Groups/ Factors/ Sources:
    Regional S04
    soil; unknown
    oil combustion
    PM variables
    used: Mass
    contribution of
    sources
    upwind from New  Results: Correlation: V and Ni positively correlated with NF-KB. Oil combustion correlated the greatest with NF-KB (0.316). Significance
    upw
    York
     'ork City
                     not provided. Only 2% of mass contribution originates from this source.
    Particle Size:
    PM2.5
    Reference: Subjects: Dogs
    Nikolov et al.
    (2008, 156808) Exposure:
    Location:
    Boston, MA
    Particle Size:
    NR
    N: 8 dogs, 24
    exposure-days
    in 1997-98; 4
    dogs, 21
    exposure-days
    in 2001 -2002
    
    Constituents
    considered for
    grouping: 13
    elements, BC, EC,
    OC
    
    Grouping
    method:
    Compared 3
    factor-analytic
    models within a
    SEM model
    # of groups: 4
    Groups/ Factors/ Sources: Oil
    Combustion V/Ni; power plants
    S ;roaddustAI/Si ;motor vehicles
    BC/OC/EC
    
    PM variables
    used: Mass
    contribution of
    every constituent
    
                     Results: Univariate response for respiratory outcomes: road dust and oil combustion associated with decreased respiratory frequency;
                     motor vehicles associated with increased respiratory frequency; motor vehicles associated with increased PEF; road dust associated
                     with decreased penh and motor vehicles associated with increased penh.
    
                     Multivariate responses for respiratory outcome: Road dust associated with decreased respiratory rate; Motor vehicles associated
                     with increased airway irritation.
    Reference:
    Rhoden et al.
    (2004, 087969)
    Location:
    Boston, MA
    Particle Size:
    PM2.5
    Reference:
    Saldiva et al.
    (2002, 025988)
    Location:
    Boston, MA
    Particle Size:
    PM2.5
    Subjects: Rats N: 4-8 rats Constituents
    (Sprague-Dawley) (1-2 per group considered for
    -sham, CAPs, grouping: 20
    Exposure: CAPs (avg. sham/NAC, elements
    mass concentration CAP/NAC)
    range 150-2520 10 exposures
    ug/m3) acetylcysteine
    full factorial
    Grouping Groups/ Factors/ Sources: NR
    method: No
    grouping was
    performed
    # of groups: NA
    PM variables
    used: Mass
    contribution of
    every constituent
    Results: Increased oxidative stress and inflammation in lungs of CAPs animals that was attenuated with NAC.
    Univariate regression: Al, Si, Fe, K, Pb, and Cu most significantly correlated with lung TBARS. No significant correlations for lung
    carbonyls or lung PMN.
    Subjects: Rats N:7-10 Constituents
    (Sprague-Dawley rats/group considered for
    (air/sham, grouping: 15
    Exposure: CAPs S02/sham, elements (used
    (3-day avg. mass air/CAP, Clarke 2000 to
    concentration range S02/CAP) x 6 select tracers)
    126.1-481 ug/m3) mns in
    different
    seasons
    Grouping Groups/ Factors/ Sources: V/Ni
    method: S
    Previous study Al/Si
    in same city Br/Pb
    (Clarke et al.
    2000) Na/CI
    Cr
    # of groups: 6
    PM variables
    used: Mass
    contribution of 8
    elements in
    univariate step.
    Tracers (Si, S04, V,
    Pb, Br, Cl) and EC,
    OC in multivariate
    step.
                     Results: Increased percent and number of PMN in majority of air and S02 rats exposed to CAPs, but significance levels not provided.
                     Other responses (protein, LDH, NAG) were variable and depended upon the CAPs exposure. No CAPs effect on histopathology.
    
                     Linear regression: V, Br, Pb, S04, EC, OC, Si, CAP mass associated with increased PMN and lymphocytes for normal+CB rats. Only V
                     not associated with PMN in normal rats. Lymphocyte response due to CB rats, but not observed for S04, Si, or mass in this group. Br,
                     Pb, S04, EC, OC, Si associated with increased total protein in CB rats. Cl and V associated with decreased LDH in CB rats. No BAL
                     effects in normal rats exposed to CAPs. V, Br, Pb, EC, OC, and Cl associated with increased neutrophil density in lungs of normal rats.
    Reference:
    Seagrave et al.
    (2006, 091291)
    Location: 4 SE
    US sites for 2
    seasons
    Particle Size:
    PM2.5
    Subjects Rats (Fisher N: 5 rats/dose
    344)
    Exposure: 0.75, 1.5
    and 3 mg/rat via
    intratracheal instillation
    Constituents
    considered for
    grouping: NR
    Grouping Groups/ Factors/ Sources: PM variables
    method: CMB secondary N03; secondary NH4; used: Mass
    secondary S04; coke production; contribution of
    # of groups: 1 3 vegetative detritus ; natural gas every constituent,
    combust; road dust; wood then mass
    combust; meat cooking gasoline; contribution of
    diesel other OM; other mass sources
    Results: Potency depended upon season and site of sample collection. In general, effects were greater in the winter.
                     PLS analysis: 2 major constituents identified (OC, Pb, hopanes/steranes, nitrate, As for first and major metal oxides for the second),
                     gasoline most important predictor for both constituents, with diesel influencing second constituent and nitrate influencing first constituent.
                     First constituent affected cytotoxic responses, second constituent affected inflammatory responses.
    December 2009
                                                                       F-9
    

    -------
    Reference: Subjects: BEAS-2B N: 6; 16 runs
    Veranthetal. cells (35000 cells/cm2; over 6 mo
    (2006. 087479) 10, 20,40,80 ug/cm2)
    Location: 8 sites Exposure: Loose
    in the western surface soil sweepings
    US through mechanical
    _ .. , _. tumbler and cascade
    Particle Size: impactor
    PM25
    Constituents Grouping Groups/ Factors/ Sources: NR
    considered for method: PLS
    grouping: 13
    elements, TC, 5 OC # of groups: NR
    variables, 4 EC
    variables, 2 ions,
    EU, one ratio (Ca:
    AI),OP,C03
    PM variables
    used: Mass
    contribution every
    constituent (?)
    
    
    
                     Results: Dose-related increase in IL-6 and decreases in cell viability for all soil types. IL-8 responses more variable and dependent upon
                     soil type. Univariate correlations. Low correlations for all constituents tested with IL-6. Highest correlations for EC1 (R = 0.50) and
                     pyrolyzed OC (R2 = 0.46), then Ca/AI (R2 = 0.21). Carbonate carbon, ECS, and Sr correlated with IL-8 (R2 = 0.27, 0.13, and 0.25,
                     respectively). EC and Ni correlated with  IL-8 trend over the range of 10-80 ug/cm2 (R2= 0.39 and 0.27, respectively). Multivariate
                     redundancy analysis OC1, OC3, OC2, EC2, Br, EC1, Ni correlated with IL-8 release, decreased viability, and decreased IL-6 at low and
                     high doses. Ni, EC1, and EC2 correlated with IL-6 release at the high dose, decreased IL-6 at the low dose, decreased IL-8 release, and
                     decreased viability. Brwas negatively associated.
    Reference:
    Wellenius et al.
    (2003, 055691)
    Location:
    Boston, MA
    
    Particle Size:
    PM2.5
    
    
    Subjects: Dogs N: 6 dogs, 20
    exposures
    Exposure: CAPs (avg.
    mass concentration
    range 161 .3-957.3
    ug/m3) repeated
    exposure with several
    weeks in between
    
    
    
    Constituents
    considered for
    grouping: 15
    elements (+EC
    OC?) (used Clarke
    etal.2000)
    
    
    
    
    
    Grouping
    method:
    Previous study
    in same city
    (Clarke et al.
    2000)
    
    # of groups: 6
    (but did not use
    all in analysis of
    health effects)
    Groups/ Factors/ Sources: V/Ni
    S
    Al/Si
    Br/Pb
    Na/CI
    Cr
    
    
    
    
    
    PM variables
    used: Univariate:
    Mass
    Number
    Ni,S,Si,BC
    Multivariate: Ni,S,
    Si.BC
    
    
    
    
                     Results: ST-segment elevation increased with CAPs.
    
                     Univariate regression: Si and Pb associated with peak ST-segment elevation and integrated ST-segment change.CAPs mass or
                     number concentration were not associated with any change.
    
                     Multivariate regression: Si associated with peak ST-segment elevation and integrated ST-segment change.
    Reference:
    Zhang etal.
    (2008, 192008)
    Location: Metro
    area of Denver,
    CO/ 45 samples
    through 1 yr
    Particle Size:
    2.5; filtered to
    0.22 um
    Subjects: Alveolar N: 45 PM
    macrophage cell line samples, 3
    (NR8383);1 xi06 runs
    cells/ml
    Exposure: Soluble
    components exposure
    concentration range
    from 20-200 pg of
    PM/cell
    Results: Started with regression on 9
    Constituents
    considered for
    grouping: 43 + EC,
    OC
    sources, then 3 (water-s
    Grouping
    method: PMF
    # of groups: 9
    Groups/Factors/ Sources:
    Mobile, water soluble carbon,
    sulfate, soil, iron, Cd and Zn point
    source, Pb, pyrotechnics,
    platinum
    PM variables
    used: Mass
    contribution of
    sources
    ;oluble carbon factor, soil dust source, iron source). Soil dust source was
                     not significant. Final regression model excluded 3 days of outliers (Fe source most significant, then water-soluble carbon factor, then soil
                     dust source) for ROS effects, with adjusted R2 of 0.774. Fe source likely associated with industrial source and includes high loadings of
                     water-soluble Fe and Ti (not identified); water-soluble C factor derived from both secondary organic aerosol and biomass smoke (largely
                     consists of polar organic compounds); soil dust source identified by water-soluble  resuspended dust elements and contains Mgand Ca.
    December 2009
    F-10
    

    -------
                                       Annex  F References
    Andersen ZJ; Wahlin P; Raaschou-Nielsen O; Scheike T; Loft S. (2007). Ambient particle source apportionment and daily
           hospital admissions among children and elderly in Copenhagen. J Expo Sci Environ Epidemiol, 17: 625-636.
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    Batalha JR; Saldiva P H; Clarke RW; Coull BA; Stearns RC; Lawrence J; Murthy GG; Koutrakis P; Godleski JJ. (2002).
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    Clarke RW; Coull B; Reinisch U; Catalano P; Killingsworth CR; Koutrakis P; Kavouras I; Murthy GGK; Lawrence J;
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     Note: Hyperlinks to the reference citations throughout this document will take you to the NCEA HERO database (Health and
     Environmental Research Online) at http://epa.gov/hero. HERO is a database of scientific literature used by U.S. EPA in the process of
     developing science assessments such as the Integrated Science Assessments (ISA) and the Integrated Risk Information System (IRIS).
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    Kodavanti UP; Schladweiler MC; Ledbetter AD; McGee JK; Walsh L; Gilmour PS; Highfill JW; Davies D; Pinkerton KE;
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    Seagrave JC; McDonald JD; Bedrick E; Edgerton ES; Gigliotti AP; Jansen JJ; Ke L; Naeher LP; Seilkop SK; Zheng M;
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           cytokine responses with the chemical composition of soil-derived particulate matter. Environ Health Perspect, 114:
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    Wellenius GA; Coull BA; Godleski JJ; Koutrakis P; Okabe K; Savage ST. (2003). Inhalation of concentrated ambient air
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    Yue W; Schneider A; Stolzel M; Ruckerl R; Cyrys J; Pan X; Zareba W; Koenig W; Wichmann HE; Peters A. (2007).
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